xref: /openbmc/linux/fs/xfs/libxfs/xfs_bmap.c (revision 550987be)
1 /*
2  * Copyright (c) 2000-2006 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_shared.h"
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
24 #include "xfs_bit.h"
25 #include "xfs_sb.h"
26 #include "xfs_mount.h"
27 #include "xfs_defer.h"
28 #include "xfs_da_format.h"
29 #include "xfs_da_btree.h"
30 #include "xfs_dir2.h"
31 #include "xfs_inode.h"
32 #include "xfs_btree.h"
33 #include "xfs_trans.h"
34 #include "xfs_inode_item.h"
35 #include "xfs_extfree_item.h"
36 #include "xfs_alloc.h"
37 #include "xfs_bmap.h"
38 #include "xfs_bmap_util.h"
39 #include "xfs_bmap_btree.h"
40 #include "xfs_rtalloc.h"
41 #include "xfs_errortag.h"
42 #include "xfs_error.h"
43 #include "xfs_quota.h"
44 #include "xfs_trans_space.h"
45 #include "xfs_buf_item.h"
46 #include "xfs_trace.h"
47 #include "xfs_symlink.h"
48 #include "xfs_attr_leaf.h"
49 #include "xfs_filestream.h"
50 #include "xfs_rmap.h"
51 #include "xfs_ag_resv.h"
52 #include "xfs_refcount.h"
53 #include "xfs_icache.h"
54 
55 
56 kmem_zone_t		*xfs_bmap_free_item_zone;
57 
58 /*
59  * Miscellaneous helper functions
60  */
61 
62 /*
63  * Compute and fill in the value of the maximum depth of a bmap btree
64  * in this filesystem.  Done once, during mount.
65  */
66 void
67 xfs_bmap_compute_maxlevels(
68 	xfs_mount_t	*mp,		/* file system mount structure */
69 	int		whichfork)	/* data or attr fork */
70 {
71 	int		level;		/* btree level */
72 	uint		maxblocks;	/* max blocks at this level */
73 	uint		maxleafents;	/* max leaf entries possible */
74 	int		maxrootrecs;	/* max records in root block */
75 	int		minleafrecs;	/* min records in leaf block */
76 	int		minnoderecs;	/* min records in node block */
77 	int		sz;		/* root block size */
78 
79 	/*
80 	 * The maximum number of extents in a file, hence the maximum
81 	 * number of leaf entries, is controlled by the type of di_nextents
82 	 * (a signed 32-bit number, xfs_extnum_t), or by di_anextents
83 	 * (a signed 16-bit number, xfs_aextnum_t).
84 	 *
85 	 * Note that we can no longer assume that if we are in ATTR1 that
86 	 * the fork offset of all the inodes will be
87 	 * (xfs_default_attroffset(ip) >> 3) because we could have mounted
88 	 * with ATTR2 and then mounted back with ATTR1, keeping the
89 	 * di_forkoff's fixed but probably at various positions. Therefore,
90 	 * for both ATTR1 and ATTR2 we have to assume the worst case scenario
91 	 * of a minimum size available.
92 	 */
93 	if (whichfork == XFS_DATA_FORK) {
94 		maxleafents = MAXEXTNUM;
95 		sz = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
96 	} else {
97 		maxleafents = MAXAEXTNUM;
98 		sz = XFS_BMDR_SPACE_CALC(MINABTPTRS);
99 	}
100 	maxrootrecs = xfs_bmdr_maxrecs(sz, 0);
101 	minleafrecs = mp->m_bmap_dmnr[0];
102 	minnoderecs = mp->m_bmap_dmnr[1];
103 	maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
104 	for (level = 1; maxblocks > 1; level++) {
105 		if (maxblocks <= maxrootrecs)
106 			maxblocks = 1;
107 		else
108 			maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
109 	}
110 	mp->m_bm_maxlevels[whichfork] = level;
111 }
112 
113 STATIC int				/* error */
114 xfs_bmbt_lookup_eq(
115 	struct xfs_btree_cur	*cur,
116 	struct xfs_bmbt_irec	*irec,
117 	int			*stat)	/* success/failure */
118 {
119 	cur->bc_rec.b = *irec;
120 	return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
121 }
122 
123 STATIC int				/* error */
124 xfs_bmbt_lookup_first(
125 	struct xfs_btree_cur	*cur,
126 	int			*stat)	/* success/failure */
127 {
128 	cur->bc_rec.b.br_startoff = 0;
129 	cur->bc_rec.b.br_startblock = 0;
130 	cur->bc_rec.b.br_blockcount = 0;
131 	return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
132 }
133 
134 /*
135  * Check if the inode needs to be converted to btree format.
136  */
137 static inline bool xfs_bmap_needs_btree(struct xfs_inode *ip, int whichfork)
138 {
139 	return whichfork != XFS_COW_FORK &&
140 		XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
141 		XFS_IFORK_NEXTENTS(ip, whichfork) >
142 			XFS_IFORK_MAXEXT(ip, whichfork);
143 }
144 
145 /*
146  * Check if the inode should be converted to extent format.
147  */
148 static inline bool xfs_bmap_wants_extents(struct xfs_inode *ip, int whichfork)
149 {
150 	return whichfork != XFS_COW_FORK &&
151 		XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE &&
152 		XFS_IFORK_NEXTENTS(ip, whichfork) <=
153 			XFS_IFORK_MAXEXT(ip, whichfork);
154 }
155 
156 /*
157  * Update the record referred to by cur to the value given by irec
158  * This either works (return 0) or gets an EFSCORRUPTED error.
159  */
160 STATIC int
161 xfs_bmbt_update(
162 	struct xfs_btree_cur	*cur,
163 	struct xfs_bmbt_irec	*irec)
164 {
165 	union xfs_btree_rec	rec;
166 
167 	xfs_bmbt_disk_set_all(&rec.bmbt, irec);
168 	return xfs_btree_update(cur, &rec);
169 }
170 
171 /*
172  * Compute the worst-case number of indirect blocks that will be used
173  * for ip's delayed extent of length "len".
174  */
175 STATIC xfs_filblks_t
176 xfs_bmap_worst_indlen(
177 	xfs_inode_t	*ip,		/* incore inode pointer */
178 	xfs_filblks_t	len)		/* delayed extent length */
179 {
180 	int		level;		/* btree level number */
181 	int		maxrecs;	/* maximum record count at this level */
182 	xfs_mount_t	*mp;		/* mount structure */
183 	xfs_filblks_t	rval;		/* return value */
184 
185 	mp = ip->i_mount;
186 	maxrecs = mp->m_bmap_dmxr[0];
187 	for (level = 0, rval = 0;
188 	     level < XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK);
189 	     level++) {
190 		len += maxrecs - 1;
191 		do_div(len, maxrecs);
192 		rval += len;
193 		if (len == 1)
194 			return rval + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) -
195 				level - 1;
196 		if (level == 0)
197 			maxrecs = mp->m_bmap_dmxr[1];
198 	}
199 	return rval;
200 }
201 
202 /*
203  * Calculate the default attribute fork offset for newly created inodes.
204  */
205 uint
206 xfs_default_attroffset(
207 	struct xfs_inode	*ip)
208 {
209 	struct xfs_mount	*mp = ip->i_mount;
210 	uint			offset;
211 
212 	if (mp->m_sb.sb_inodesize == 256) {
213 		offset = XFS_LITINO(mp, ip->i_d.di_version) -
214 				XFS_BMDR_SPACE_CALC(MINABTPTRS);
215 	} else {
216 		offset = XFS_BMDR_SPACE_CALC(6 * MINABTPTRS);
217 	}
218 
219 	ASSERT(offset < XFS_LITINO(mp, ip->i_d.di_version));
220 	return offset;
221 }
222 
223 /*
224  * Helper routine to reset inode di_forkoff field when switching
225  * attribute fork from local to extent format - we reset it where
226  * possible to make space available for inline data fork extents.
227  */
228 STATIC void
229 xfs_bmap_forkoff_reset(
230 	xfs_inode_t	*ip,
231 	int		whichfork)
232 {
233 	if (whichfork == XFS_ATTR_FORK &&
234 	    ip->i_d.di_format != XFS_DINODE_FMT_DEV &&
235 	    ip->i_d.di_format != XFS_DINODE_FMT_BTREE) {
236 		uint	dfl_forkoff = xfs_default_attroffset(ip) >> 3;
237 
238 		if (dfl_forkoff > ip->i_d.di_forkoff)
239 			ip->i_d.di_forkoff = dfl_forkoff;
240 	}
241 }
242 
243 #ifdef DEBUG
244 STATIC struct xfs_buf *
245 xfs_bmap_get_bp(
246 	struct xfs_btree_cur	*cur,
247 	xfs_fsblock_t		bno)
248 {
249 	struct xfs_log_item_desc *lidp;
250 	int			i;
251 
252 	if (!cur)
253 		return NULL;
254 
255 	for (i = 0; i < XFS_BTREE_MAXLEVELS; i++) {
256 		if (!cur->bc_bufs[i])
257 			break;
258 		if (XFS_BUF_ADDR(cur->bc_bufs[i]) == bno)
259 			return cur->bc_bufs[i];
260 	}
261 
262 	/* Chase down all the log items to see if the bp is there */
263 	list_for_each_entry(lidp, &cur->bc_tp->t_items, lid_trans) {
264 		struct xfs_buf_log_item	*bip;
265 		bip = (struct xfs_buf_log_item *)lidp->lid_item;
266 		if (bip->bli_item.li_type == XFS_LI_BUF &&
267 		    XFS_BUF_ADDR(bip->bli_buf) == bno)
268 			return bip->bli_buf;
269 	}
270 
271 	return NULL;
272 }
273 
274 STATIC void
275 xfs_check_block(
276 	struct xfs_btree_block	*block,
277 	xfs_mount_t		*mp,
278 	int			root,
279 	short			sz)
280 {
281 	int			i, j, dmxr;
282 	__be64			*pp, *thispa;	/* pointer to block address */
283 	xfs_bmbt_key_t		*prevp, *keyp;
284 
285 	ASSERT(be16_to_cpu(block->bb_level) > 0);
286 
287 	prevp = NULL;
288 	for( i = 1; i <= xfs_btree_get_numrecs(block); i++) {
289 		dmxr = mp->m_bmap_dmxr[0];
290 		keyp = XFS_BMBT_KEY_ADDR(mp, block, i);
291 
292 		if (prevp) {
293 			ASSERT(be64_to_cpu(prevp->br_startoff) <
294 			       be64_to_cpu(keyp->br_startoff));
295 		}
296 		prevp = keyp;
297 
298 		/*
299 		 * Compare the block numbers to see if there are dups.
300 		 */
301 		if (root)
302 			pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, i, sz);
303 		else
304 			pp = XFS_BMBT_PTR_ADDR(mp, block, i, dmxr);
305 
306 		for (j = i+1; j <= be16_to_cpu(block->bb_numrecs); j++) {
307 			if (root)
308 				thispa = XFS_BMAP_BROOT_PTR_ADDR(mp, block, j, sz);
309 			else
310 				thispa = XFS_BMBT_PTR_ADDR(mp, block, j, dmxr);
311 			if (*thispa == *pp) {
312 				xfs_warn(mp, "%s: thispa(%d) == pp(%d) %Ld",
313 					__func__, j, i,
314 					(unsigned long long)be64_to_cpu(*thispa));
315 				panic("%s: ptrs are equal in node\n",
316 					__func__);
317 			}
318 		}
319 	}
320 }
321 
322 /*
323  * Check that the extents for the inode ip are in the right order in all
324  * btree leaves. THis becomes prohibitively expensive for large extent count
325  * files, so don't bother with inodes that have more than 10,000 extents in
326  * them. The btree record ordering checks will still be done, so for such large
327  * bmapbt constructs that is going to catch most corruptions.
328  */
329 STATIC void
330 xfs_bmap_check_leaf_extents(
331 	xfs_btree_cur_t		*cur,	/* btree cursor or null */
332 	xfs_inode_t		*ip,		/* incore inode pointer */
333 	int			whichfork)	/* data or attr fork */
334 {
335 	struct xfs_btree_block	*block;	/* current btree block */
336 	xfs_fsblock_t		bno;	/* block # of "block" */
337 	xfs_buf_t		*bp;	/* buffer for "block" */
338 	int			error;	/* error return value */
339 	xfs_extnum_t		i=0, j;	/* index into the extents list */
340 	xfs_ifork_t		*ifp;	/* fork structure */
341 	int			level;	/* btree level, for checking */
342 	xfs_mount_t		*mp;	/* file system mount structure */
343 	__be64			*pp;	/* pointer to block address */
344 	xfs_bmbt_rec_t		*ep;	/* pointer to current extent */
345 	xfs_bmbt_rec_t		last = {0, 0}; /* last extent in prev block */
346 	xfs_bmbt_rec_t		*nextp;	/* pointer to next extent */
347 	int			bp_release = 0;
348 
349 	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE) {
350 		return;
351 	}
352 
353 	/* skip large extent count inodes */
354 	if (ip->i_d.di_nextents > 10000)
355 		return;
356 
357 	bno = NULLFSBLOCK;
358 	mp = ip->i_mount;
359 	ifp = XFS_IFORK_PTR(ip, whichfork);
360 	block = ifp->if_broot;
361 	/*
362 	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
363 	 */
364 	level = be16_to_cpu(block->bb_level);
365 	ASSERT(level > 0);
366 	xfs_check_block(block, mp, 1, ifp->if_broot_bytes);
367 	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
368 	bno = be64_to_cpu(*pp);
369 
370 	ASSERT(bno != NULLFSBLOCK);
371 	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
372 	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
373 
374 	/*
375 	 * Go down the tree until leaf level is reached, following the first
376 	 * pointer (leftmost) at each level.
377 	 */
378 	while (level-- > 0) {
379 		/* See if buf is in cur first */
380 		bp_release = 0;
381 		bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
382 		if (!bp) {
383 			bp_release = 1;
384 			error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
385 						XFS_BMAP_BTREE_REF,
386 						&xfs_bmbt_buf_ops);
387 			if (error)
388 				goto error_norelse;
389 		}
390 		block = XFS_BUF_TO_BLOCK(bp);
391 		if (level == 0)
392 			break;
393 
394 		/*
395 		 * Check this block for basic sanity (increasing keys and
396 		 * no duplicate blocks).
397 		 */
398 
399 		xfs_check_block(block, mp, 0, 0);
400 		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
401 		bno = be64_to_cpu(*pp);
402 		XFS_WANT_CORRUPTED_GOTO(mp,
403 					xfs_verify_fsbno(mp, bno), error0);
404 		if (bp_release) {
405 			bp_release = 0;
406 			xfs_trans_brelse(NULL, bp);
407 		}
408 	}
409 
410 	/*
411 	 * Here with bp and block set to the leftmost leaf node in the tree.
412 	 */
413 	i = 0;
414 
415 	/*
416 	 * Loop over all leaf nodes checking that all extents are in the right order.
417 	 */
418 	for (;;) {
419 		xfs_fsblock_t	nextbno;
420 		xfs_extnum_t	num_recs;
421 
422 
423 		num_recs = xfs_btree_get_numrecs(block);
424 
425 		/*
426 		 * Read-ahead the next leaf block, if any.
427 		 */
428 
429 		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
430 
431 		/*
432 		 * Check all the extents to make sure they are OK.
433 		 * If we had a previous block, the last entry should
434 		 * conform with the first entry in this one.
435 		 */
436 
437 		ep = XFS_BMBT_REC_ADDR(mp, block, 1);
438 		if (i) {
439 			ASSERT(xfs_bmbt_disk_get_startoff(&last) +
440 			       xfs_bmbt_disk_get_blockcount(&last) <=
441 			       xfs_bmbt_disk_get_startoff(ep));
442 		}
443 		for (j = 1; j < num_recs; j++) {
444 			nextp = XFS_BMBT_REC_ADDR(mp, block, j + 1);
445 			ASSERT(xfs_bmbt_disk_get_startoff(ep) +
446 			       xfs_bmbt_disk_get_blockcount(ep) <=
447 			       xfs_bmbt_disk_get_startoff(nextp));
448 			ep = nextp;
449 		}
450 
451 		last = *ep;
452 		i += num_recs;
453 		if (bp_release) {
454 			bp_release = 0;
455 			xfs_trans_brelse(NULL, bp);
456 		}
457 		bno = nextbno;
458 		/*
459 		 * If we've reached the end, stop.
460 		 */
461 		if (bno == NULLFSBLOCK)
462 			break;
463 
464 		bp_release = 0;
465 		bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
466 		if (!bp) {
467 			bp_release = 1;
468 			error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
469 						XFS_BMAP_BTREE_REF,
470 						&xfs_bmbt_buf_ops);
471 			if (error)
472 				goto error_norelse;
473 		}
474 		block = XFS_BUF_TO_BLOCK(bp);
475 	}
476 
477 	return;
478 
479 error0:
480 	xfs_warn(mp, "%s: at error0", __func__);
481 	if (bp_release)
482 		xfs_trans_brelse(NULL, bp);
483 error_norelse:
484 	xfs_warn(mp, "%s: BAD after btree leaves for %d extents",
485 		__func__, i);
486 	panic("%s: CORRUPTED BTREE OR SOMETHING", __func__);
487 	return;
488 }
489 
490 /*
491  * Validate that the bmbt_irecs being returned from bmapi are valid
492  * given the caller's original parameters.  Specifically check the
493  * ranges of the returned irecs to ensure that they only extend beyond
494  * the given parameters if the XFS_BMAPI_ENTIRE flag was set.
495  */
496 STATIC void
497 xfs_bmap_validate_ret(
498 	xfs_fileoff_t		bno,
499 	xfs_filblks_t		len,
500 	int			flags,
501 	xfs_bmbt_irec_t		*mval,
502 	int			nmap,
503 	int			ret_nmap)
504 {
505 	int			i;		/* index to map values */
506 
507 	ASSERT(ret_nmap <= nmap);
508 
509 	for (i = 0; i < ret_nmap; i++) {
510 		ASSERT(mval[i].br_blockcount > 0);
511 		if (!(flags & XFS_BMAPI_ENTIRE)) {
512 			ASSERT(mval[i].br_startoff >= bno);
513 			ASSERT(mval[i].br_blockcount <= len);
514 			ASSERT(mval[i].br_startoff + mval[i].br_blockcount <=
515 			       bno + len);
516 		} else {
517 			ASSERT(mval[i].br_startoff < bno + len);
518 			ASSERT(mval[i].br_startoff + mval[i].br_blockcount >
519 			       bno);
520 		}
521 		ASSERT(i == 0 ||
522 		       mval[i - 1].br_startoff + mval[i - 1].br_blockcount ==
523 		       mval[i].br_startoff);
524 		ASSERT(mval[i].br_startblock != DELAYSTARTBLOCK &&
525 		       mval[i].br_startblock != HOLESTARTBLOCK);
526 		ASSERT(mval[i].br_state == XFS_EXT_NORM ||
527 		       mval[i].br_state == XFS_EXT_UNWRITTEN);
528 	}
529 }
530 
531 #else
532 #define xfs_bmap_check_leaf_extents(cur, ip, whichfork)		do { } while (0)
533 #define	xfs_bmap_validate_ret(bno,len,flags,mval,onmap,nmap)	do { } while (0)
534 #endif /* DEBUG */
535 
536 /*
537  * bmap free list manipulation functions
538  */
539 
540 /*
541  * Add the extent to the list of extents to be free at transaction end.
542  * The list is maintained sorted (by block number).
543  */
544 void
545 xfs_bmap_add_free(
546 	struct xfs_mount		*mp,
547 	struct xfs_defer_ops		*dfops,
548 	xfs_fsblock_t			bno,
549 	xfs_filblks_t			len,
550 	struct xfs_owner_info		*oinfo)
551 {
552 	struct xfs_extent_free_item	*new;		/* new element */
553 #ifdef DEBUG
554 	xfs_agnumber_t		agno;
555 	xfs_agblock_t		agbno;
556 
557 	ASSERT(bno != NULLFSBLOCK);
558 	ASSERT(len > 0);
559 	ASSERT(len <= MAXEXTLEN);
560 	ASSERT(!isnullstartblock(bno));
561 	agno = XFS_FSB_TO_AGNO(mp, bno);
562 	agbno = XFS_FSB_TO_AGBNO(mp, bno);
563 	ASSERT(agno < mp->m_sb.sb_agcount);
564 	ASSERT(agbno < mp->m_sb.sb_agblocks);
565 	ASSERT(len < mp->m_sb.sb_agblocks);
566 	ASSERT(agbno + len <= mp->m_sb.sb_agblocks);
567 #endif
568 	ASSERT(xfs_bmap_free_item_zone != NULL);
569 
570 	new = kmem_zone_alloc(xfs_bmap_free_item_zone, KM_SLEEP);
571 	new->xefi_startblock = bno;
572 	new->xefi_blockcount = (xfs_extlen_t)len;
573 	if (oinfo)
574 		new->xefi_oinfo = *oinfo;
575 	else
576 		xfs_rmap_skip_owner_update(&new->xefi_oinfo);
577 	trace_xfs_bmap_free_defer(mp, XFS_FSB_TO_AGNO(mp, bno), 0,
578 			XFS_FSB_TO_AGBNO(mp, bno), len);
579 	xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_FREE, &new->xefi_list);
580 }
581 
582 /*
583  * Inode fork format manipulation functions
584  */
585 
586 /*
587  * Transform a btree format file with only one leaf node, where the
588  * extents list will fit in the inode, into an extents format file.
589  * Since the file extents are already in-core, all we have to do is
590  * give up the space for the btree root and pitch the leaf block.
591  */
592 STATIC int				/* error */
593 xfs_bmap_btree_to_extents(
594 	xfs_trans_t		*tp,	/* transaction pointer */
595 	xfs_inode_t		*ip,	/* incore inode pointer */
596 	xfs_btree_cur_t		*cur,	/* btree cursor */
597 	int			*logflagsp, /* inode logging flags */
598 	int			whichfork)  /* data or attr fork */
599 {
600 	/* REFERENCED */
601 	struct xfs_btree_block	*cblock;/* child btree block */
602 	xfs_fsblock_t		cbno;	/* child block number */
603 	xfs_buf_t		*cbp;	/* child block's buffer */
604 	int			error;	/* error return value */
605 	xfs_ifork_t		*ifp;	/* inode fork data */
606 	xfs_mount_t		*mp;	/* mount point structure */
607 	__be64			*pp;	/* ptr to block address */
608 	struct xfs_btree_block	*rblock;/* root btree block */
609 	struct xfs_owner_info	oinfo;
610 
611 	mp = ip->i_mount;
612 	ifp = XFS_IFORK_PTR(ip, whichfork);
613 	ASSERT(whichfork != XFS_COW_FORK);
614 	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
615 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
616 	rblock = ifp->if_broot;
617 	ASSERT(be16_to_cpu(rblock->bb_level) == 1);
618 	ASSERT(be16_to_cpu(rblock->bb_numrecs) == 1);
619 	ASSERT(xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0) == 1);
620 	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, ifp->if_broot_bytes);
621 	cbno = be64_to_cpu(*pp);
622 	*logflagsp = 0;
623 #ifdef DEBUG
624 	XFS_WANT_CORRUPTED_RETURN(cur->bc_mp,
625 			xfs_btree_check_lptr(cur, cbno, 1));
626 #endif
627 	error = xfs_btree_read_bufl(mp, tp, cbno, 0, &cbp, XFS_BMAP_BTREE_REF,
628 				&xfs_bmbt_buf_ops);
629 	if (error)
630 		return error;
631 	cblock = XFS_BUF_TO_BLOCK(cbp);
632 	if ((error = xfs_btree_check_block(cur, cblock, 0, cbp)))
633 		return error;
634 	xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, whichfork);
635 	xfs_bmap_add_free(mp, cur->bc_private.b.dfops, cbno, 1, &oinfo);
636 	ip->i_d.di_nblocks--;
637 	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
638 	xfs_trans_binval(tp, cbp);
639 	if (cur->bc_bufs[0] == cbp)
640 		cur->bc_bufs[0] = NULL;
641 	xfs_iroot_realloc(ip, -1, whichfork);
642 	ASSERT(ifp->if_broot == NULL);
643 	ASSERT((ifp->if_flags & XFS_IFBROOT) == 0);
644 	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
645 	*logflagsp = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
646 	return 0;
647 }
648 
649 /*
650  * Convert an extents-format file into a btree-format file.
651  * The new file will have a root block (in the inode) and a single child block.
652  */
653 STATIC int					/* error */
654 xfs_bmap_extents_to_btree(
655 	xfs_trans_t		*tp,		/* transaction pointer */
656 	xfs_inode_t		*ip,		/* incore inode pointer */
657 	xfs_fsblock_t		*firstblock,	/* first-block-allocated */
658 	struct xfs_defer_ops	*dfops,		/* blocks freed in xaction */
659 	xfs_btree_cur_t		**curp,		/* cursor returned to caller */
660 	int			wasdel,		/* converting a delayed alloc */
661 	int			*logflagsp,	/* inode logging flags */
662 	int			whichfork)	/* data or attr fork */
663 {
664 	struct xfs_btree_block	*ablock;	/* allocated (child) bt block */
665 	xfs_buf_t		*abp;		/* buffer for ablock */
666 	xfs_alloc_arg_t		args;		/* allocation arguments */
667 	xfs_bmbt_rec_t		*arp;		/* child record pointer */
668 	struct xfs_btree_block	*block;		/* btree root block */
669 	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
670 	int			error;		/* error return value */
671 	xfs_ifork_t		*ifp;		/* inode fork pointer */
672 	xfs_bmbt_key_t		*kp;		/* root block key pointer */
673 	xfs_mount_t		*mp;		/* mount structure */
674 	xfs_bmbt_ptr_t		*pp;		/* root block address pointer */
675 	struct xfs_iext_cursor	icur;
676 	struct xfs_bmbt_irec	rec;
677 	xfs_extnum_t		cnt = 0;
678 
679 	mp = ip->i_mount;
680 	ASSERT(whichfork != XFS_COW_FORK);
681 	ifp = XFS_IFORK_PTR(ip, whichfork);
682 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS);
683 
684 	/*
685 	 * Make space in the inode incore.
686 	 */
687 	xfs_iroot_realloc(ip, 1, whichfork);
688 	ifp->if_flags |= XFS_IFBROOT;
689 
690 	/*
691 	 * Fill in the root.
692 	 */
693 	block = ifp->if_broot;
694 	xfs_btree_init_block_int(mp, block, XFS_BUF_DADDR_NULL,
695 				 XFS_BTNUM_BMAP, 1, 1, ip->i_ino,
696 				 XFS_BTREE_LONG_PTRS);
697 	/*
698 	 * Need a cursor.  Can't allocate until bb_level is filled in.
699 	 */
700 	cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
701 	cur->bc_private.b.firstblock = *firstblock;
702 	cur->bc_private.b.dfops = dfops;
703 	cur->bc_private.b.flags = wasdel ? XFS_BTCUR_BPRV_WASDEL : 0;
704 	/*
705 	 * Convert to a btree with two levels, one record in root.
706 	 */
707 	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_BTREE);
708 	memset(&args, 0, sizeof(args));
709 	args.tp = tp;
710 	args.mp = mp;
711 	xfs_rmap_ino_bmbt_owner(&args.oinfo, ip->i_ino, whichfork);
712 	args.firstblock = *firstblock;
713 	if (*firstblock == NULLFSBLOCK) {
714 		args.type = XFS_ALLOCTYPE_START_BNO;
715 		args.fsbno = XFS_INO_TO_FSB(mp, ip->i_ino);
716 	} else if (dfops->dop_low) {
717 		args.type = XFS_ALLOCTYPE_START_BNO;
718 		args.fsbno = *firstblock;
719 	} else {
720 		args.type = XFS_ALLOCTYPE_NEAR_BNO;
721 		args.fsbno = *firstblock;
722 	}
723 	args.minlen = args.maxlen = args.prod = 1;
724 	args.wasdel = wasdel;
725 	*logflagsp = 0;
726 	if ((error = xfs_alloc_vextent(&args))) {
727 		xfs_iroot_realloc(ip, -1, whichfork);
728 		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
729 		return error;
730 	}
731 
732 	if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) {
733 		xfs_iroot_realloc(ip, -1, whichfork);
734 		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
735 		return -ENOSPC;
736 	}
737 	/*
738 	 * Allocation can't fail, the space was reserved.
739 	 */
740 	ASSERT(*firstblock == NULLFSBLOCK ||
741 	       args.agno >= XFS_FSB_TO_AGNO(mp, *firstblock));
742 	*firstblock = cur->bc_private.b.firstblock = args.fsbno;
743 	cur->bc_private.b.allocated++;
744 	ip->i_d.di_nblocks++;
745 	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, 1L);
746 	abp = xfs_btree_get_bufl(mp, tp, args.fsbno, 0);
747 	/*
748 	 * Fill in the child block.
749 	 */
750 	abp->b_ops = &xfs_bmbt_buf_ops;
751 	ablock = XFS_BUF_TO_BLOCK(abp);
752 	xfs_btree_init_block_int(mp, ablock, abp->b_bn,
753 				XFS_BTNUM_BMAP, 0, 0, ip->i_ino,
754 				XFS_BTREE_LONG_PTRS);
755 
756 	for_each_xfs_iext(ifp, &icur, &rec) {
757 		if (isnullstartblock(rec.br_startblock))
758 			continue;
759 		arp = XFS_BMBT_REC_ADDR(mp, ablock, 1 + cnt);
760 		xfs_bmbt_disk_set_all(arp, &rec);
761 		cnt++;
762 	}
763 	ASSERT(cnt == XFS_IFORK_NEXTENTS(ip, whichfork));
764 	xfs_btree_set_numrecs(ablock, cnt);
765 
766 	/*
767 	 * Fill in the root key and pointer.
768 	 */
769 	kp = XFS_BMBT_KEY_ADDR(mp, block, 1);
770 	arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
771 	kp->br_startoff = cpu_to_be64(xfs_bmbt_disk_get_startoff(arp));
772 	pp = XFS_BMBT_PTR_ADDR(mp, block, 1, xfs_bmbt_get_maxrecs(cur,
773 						be16_to_cpu(block->bb_level)));
774 	*pp = cpu_to_be64(args.fsbno);
775 
776 	/*
777 	 * Do all this logging at the end so that
778 	 * the root is at the right level.
779 	 */
780 	xfs_btree_log_block(cur, abp, XFS_BB_ALL_BITS);
781 	xfs_btree_log_recs(cur, abp, 1, be16_to_cpu(ablock->bb_numrecs));
782 	ASSERT(*curp == NULL);
783 	*curp = cur;
784 	*logflagsp = XFS_ILOG_CORE | xfs_ilog_fbroot(whichfork);
785 	return 0;
786 }
787 
788 /*
789  * Convert a local file to an extents file.
790  * This code is out of bounds for data forks of regular files,
791  * since the file data needs to get logged so things will stay consistent.
792  * (The bmap-level manipulations are ok, though).
793  */
794 void
795 xfs_bmap_local_to_extents_empty(
796 	struct xfs_inode	*ip,
797 	int			whichfork)
798 {
799 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
800 
801 	ASSERT(whichfork != XFS_COW_FORK);
802 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
803 	ASSERT(ifp->if_bytes == 0);
804 	ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) == 0);
805 
806 	xfs_bmap_forkoff_reset(ip, whichfork);
807 	ifp->if_flags &= ~XFS_IFINLINE;
808 	ifp->if_flags |= XFS_IFEXTENTS;
809 	ifp->if_u1.if_root = NULL;
810 	ifp->if_height = 0;
811 	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
812 }
813 
814 
815 STATIC int				/* error */
816 xfs_bmap_local_to_extents(
817 	xfs_trans_t	*tp,		/* transaction pointer */
818 	xfs_inode_t	*ip,		/* incore inode pointer */
819 	xfs_fsblock_t	*firstblock,	/* first block allocated in xaction */
820 	xfs_extlen_t	total,		/* total blocks needed by transaction */
821 	int		*logflagsp,	/* inode logging flags */
822 	int		whichfork,
823 	void		(*init_fn)(struct xfs_trans *tp,
824 				   struct xfs_buf *bp,
825 				   struct xfs_inode *ip,
826 				   struct xfs_ifork *ifp))
827 {
828 	int		error = 0;
829 	int		flags;		/* logging flags returned */
830 	xfs_ifork_t	*ifp;		/* inode fork pointer */
831 	xfs_alloc_arg_t	args;		/* allocation arguments */
832 	xfs_buf_t	*bp;		/* buffer for extent block */
833 	struct xfs_bmbt_irec rec;
834 	struct xfs_iext_cursor icur;
835 
836 	/*
837 	 * We don't want to deal with the case of keeping inode data inline yet.
838 	 * So sending the data fork of a regular inode is invalid.
839 	 */
840 	ASSERT(!(S_ISREG(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK));
841 	ifp = XFS_IFORK_PTR(ip, whichfork);
842 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
843 
844 	if (!ifp->if_bytes) {
845 		xfs_bmap_local_to_extents_empty(ip, whichfork);
846 		flags = XFS_ILOG_CORE;
847 		goto done;
848 	}
849 
850 	flags = 0;
851 	error = 0;
852 	ASSERT((ifp->if_flags & (XFS_IFINLINE|XFS_IFEXTENTS)) == XFS_IFINLINE);
853 	memset(&args, 0, sizeof(args));
854 	args.tp = tp;
855 	args.mp = ip->i_mount;
856 	xfs_rmap_ino_owner(&args.oinfo, ip->i_ino, whichfork, 0);
857 	args.firstblock = *firstblock;
858 	/*
859 	 * Allocate a block.  We know we need only one, since the
860 	 * file currently fits in an inode.
861 	 */
862 	if (*firstblock == NULLFSBLOCK) {
863 		args.fsbno = XFS_INO_TO_FSB(args.mp, ip->i_ino);
864 		args.type = XFS_ALLOCTYPE_START_BNO;
865 	} else {
866 		args.fsbno = *firstblock;
867 		args.type = XFS_ALLOCTYPE_NEAR_BNO;
868 	}
869 	args.total = total;
870 	args.minlen = args.maxlen = args.prod = 1;
871 	error = xfs_alloc_vextent(&args);
872 	if (error)
873 		goto done;
874 
875 	/* Can't fail, the space was reserved. */
876 	ASSERT(args.fsbno != NULLFSBLOCK);
877 	ASSERT(args.len == 1);
878 	*firstblock = args.fsbno;
879 	bp = xfs_btree_get_bufl(args.mp, tp, args.fsbno, 0);
880 
881 	/*
882 	 * Initialize the block, copy the data and log the remote buffer.
883 	 *
884 	 * The callout is responsible for logging because the remote format
885 	 * might differ from the local format and thus we don't know how much to
886 	 * log here. Note that init_fn must also set the buffer log item type
887 	 * correctly.
888 	 */
889 	init_fn(tp, bp, ip, ifp);
890 
891 	/* account for the change in fork size */
892 	xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
893 	xfs_bmap_local_to_extents_empty(ip, whichfork);
894 	flags |= XFS_ILOG_CORE;
895 
896 	ifp->if_u1.if_root = NULL;
897 	ifp->if_height = 0;
898 
899 	rec.br_startoff = 0;
900 	rec.br_startblock = args.fsbno;
901 	rec.br_blockcount = 1;
902 	rec.br_state = XFS_EXT_NORM;
903 	xfs_iext_first(ifp, &icur);
904 	xfs_iext_insert(ip, &icur, &rec, 0);
905 
906 	XFS_IFORK_NEXT_SET(ip, whichfork, 1);
907 	ip->i_d.di_nblocks = 1;
908 	xfs_trans_mod_dquot_byino(tp, ip,
909 		XFS_TRANS_DQ_BCOUNT, 1L);
910 	flags |= xfs_ilog_fext(whichfork);
911 
912 done:
913 	*logflagsp = flags;
914 	return error;
915 }
916 
917 /*
918  * Called from xfs_bmap_add_attrfork to handle btree format files.
919  */
920 STATIC int					/* error */
921 xfs_bmap_add_attrfork_btree(
922 	xfs_trans_t		*tp,		/* transaction pointer */
923 	xfs_inode_t		*ip,		/* incore inode pointer */
924 	xfs_fsblock_t		*firstblock,	/* first block allocated */
925 	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
926 	int			*flags)		/* inode logging flags */
927 {
928 	xfs_btree_cur_t		*cur;		/* btree cursor */
929 	int			error;		/* error return value */
930 	xfs_mount_t		*mp;		/* file system mount struct */
931 	int			stat;		/* newroot status */
932 
933 	mp = ip->i_mount;
934 	if (ip->i_df.if_broot_bytes <= XFS_IFORK_DSIZE(ip))
935 		*flags |= XFS_ILOG_DBROOT;
936 	else {
937 		cur = xfs_bmbt_init_cursor(mp, tp, ip, XFS_DATA_FORK);
938 		cur->bc_private.b.dfops = dfops;
939 		cur->bc_private.b.firstblock = *firstblock;
940 		error = xfs_bmbt_lookup_first(cur, &stat);
941 		if (error)
942 			goto error0;
943 		/* must be at least one entry */
944 		XFS_WANT_CORRUPTED_GOTO(mp, stat == 1, error0);
945 		if ((error = xfs_btree_new_iroot(cur, flags, &stat)))
946 			goto error0;
947 		if (stat == 0) {
948 			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
949 			return -ENOSPC;
950 		}
951 		*firstblock = cur->bc_private.b.firstblock;
952 		cur->bc_private.b.allocated = 0;
953 		xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
954 	}
955 	return 0;
956 error0:
957 	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
958 	return error;
959 }
960 
961 /*
962  * Called from xfs_bmap_add_attrfork to handle extents format files.
963  */
964 STATIC int					/* error */
965 xfs_bmap_add_attrfork_extents(
966 	xfs_trans_t		*tp,		/* transaction pointer */
967 	xfs_inode_t		*ip,		/* incore inode pointer */
968 	xfs_fsblock_t		*firstblock,	/* first block allocated */
969 	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
970 	int			*flags)		/* inode logging flags */
971 {
972 	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
973 	int			error;		/* error return value */
974 
975 	if (ip->i_d.di_nextents * sizeof(xfs_bmbt_rec_t) <= XFS_IFORK_DSIZE(ip))
976 		return 0;
977 	cur = NULL;
978 	error = xfs_bmap_extents_to_btree(tp, ip, firstblock, dfops, &cur, 0,
979 		flags, XFS_DATA_FORK);
980 	if (cur) {
981 		cur->bc_private.b.allocated = 0;
982 		xfs_btree_del_cursor(cur,
983 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
984 	}
985 	return error;
986 }
987 
988 /*
989  * Called from xfs_bmap_add_attrfork to handle local format files. Each
990  * different data fork content type needs a different callout to do the
991  * conversion. Some are basic and only require special block initialisation
992  * callouts for the data formating, others (directories) are so specialised they
993  * handle everything themselves.
994  *
995  * XXX (dgc): investigate whether directory conversion can use the generic
996  * formatting callout. It should be possible - it's just a very complex
997  * formatter.
998  */
999 STATIC int					/* error */
1000 xfs_bmap_add_attrfork_local(
1001 	xfs_trans_t		*tp,		/* transaction pointer */
1002 	xfs_inode_t		*ip,		/* incore inode pointer */
1003 	xfs_fsblock_t		*firstblock,	/* first block allocated */
1004 	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
1005 	int			*flags)		/* inode logging flags */
1006 {
1007 	xfs_da_args_t		dargs;		/* args for dir/attr code */
1008 
1009 	if (ip->i_df.if_bytes <= XFS_IFORK_DSIZE(ip))
1010 		return 0;
1011 
1012 	if (S_ISDIR(VFS_I(ip)->i_mode)) {
1013 		memset(&dargs, 0, sizeof(dargs));
1014 		dargs.geo = ip->i_mount->m_dir_geo;
1015 		dargs.dp = ip;
1016 		dargs.firstblock = firstblock;
1017 		dargs.dfops = dfops;
1018 		dargs.total = dargs.geo->fsbcount;
1019 		dargs.whichfork = XFS_DATA_FORK;
1020 		dargs.trans = tp;
1021 		return xfs_dir2_sf_to_block(&dargs);
1022 	}
1023 
1024 	if (S_ISLNK(VFS_I(ip)->i_mode))
1025 		return xfs_bmap_local_to_extents(tp, ip, firstblock, 1,
1026 						 flags, XFS_DATA_FORK,
1027 						 xfs_symlink_local_to_remote);
1028 
1029 	/* should only be called for types that support local format data */
1030 	ASSERT(0);
1031 	return -EFSCORRUPTED;
1032 }
1033 
1034 /*
1035  * Convert inode from non-attributed to attributed.
1036  * Must not be in a transaction, ip must not be locked.
1037  */
1038 int						/* error code */
1039 xfs_bmap_add_attrfork(
1040 	xfs_inode_t		*ip,		/* incore inode pointer */
1041 	int			size,		/* space new attribute needs */
1042 	int			rsvd)		/* xact may use reserved blks */
1043 {
1044 	xfs_fsblock_t		firstblock;	/* 1st block/ag allocated */
1045 	struct xfs_defer_ops	dfops;		/* freed extent records */
1046 	xfs_mount_t		*mp;		/* mount structure */
1047 	xfs_trans_t		*tp;		/* transaction pointer */
1048 	int			blks;		/* space reservation */
1049 	int			version = 1;	/* superblock attr version */
1050 	int			logflags;	/* logging flags */
1051 	int			error;		/* error return value */
1052 
1053 	ASSERT(XFS_IFORK_Q(ip) == 0);
1054 
1055 	mp = ip->i_mount;
1056 	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1057 
1058 	blks = XFS_ADDAFORK_SPACE_RES(mp);
1059 
1060 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_addafork, blks, 0,
1061 			rsvd ? XFS_TRANS_RESERVE : 0, &tp);
1062 	if (error)
1063 		return error;
1064 
1065 	xfs_ilock(ip, XFS_ILOCK_EXCL);
1066 	error = xfs_trans_reserve_quota_nblks(tp, ip, blks, 0, rsvd ?
1067 			XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
1068 			XFS_QMOPT_RES_REGBLKS);
1069 	if (error)
1070 		goto trans_cancel;
1071 	if (XFS_IFORK_Q(ip))
1072 		goto trans_cancel;
1073 	if (ip->i_d.di_anextents != 0) {
1074 		error = -EFSCORRUPTED;
1075 		goto trans_cancel;
1076 	}
1077 	if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS) {
1078 		/*
1079 		 * For inodes coming from pre-6.2 filesystems.
1080 		 */
1081 		ASSERT(ip->i_d.di_aformat == 0);
1082 		ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
1083 	}
1084 
1085 	xfs_trans_ijoin(tp, ip, 0);
1086 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1087 
1088 	switch (ip->i_d.di_format) {
1089 	case XFS_DINODE_FMT_DEV:
1090 		ip->i_d.di_forkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
1091 		break;
1092 	case XFS_DINODE_FMT_LOCAL:
1093 	case XFS_DINODE_FMT_EXTENTS:
1094 	case XFS_DINODE_FMT_BTREE:
1095 		ip->i_d.di_forkoff = xfs_attr_shortform_bytesfit(ip, size);
1096 		if (!ip->i_d.di_forkoff)
1097 			ip->i_d.di_forkoff = xfs_default_attroffset(ip) >> 3;
1098 		else if (mp->m_flags & XFS_MOUNT_ATTR2)
1099 			version = 2;
1100 		break;
1101 	default:
1102 		ASSERT(0);
1103 		error = -EINVAL;
1104 		goto trans_cancel;
1105 	}
1106 
1107 	ASSERT(ip->i_afp == NULL);
1108 	ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP);
1109 	ip->i_afp->if_flags = XFS_IFEXTENTS;
1110 	logflags = 0;
1111 	xfs_defer_init(&dfops, &firstblock);
1112 	switch (ip->i_d.di_format) {
1113 	case XFS_DINODE_FMT_LOCAL:
1114 		error = xfs_bmap_add_attrfork_local(tp, ip, &firstblock, &dfops,
1115 			&logflags);
1116 		break;
1117 	case XFS_DINODE_FMT_EXTENTS:
1118 		error = xfs_bmap_add_attrfork_extents(tp, ip, &firstblock,
1119 			&dfops, &logflags);
1120 		break;
1121 	case XFS_DINODE_FMT_BTREE:
1122 		error = xfs_bmap_add_attrfork_btree(tp, ip, &firstblock, &dfops,
1123 			&logflags);
1124 		break;
1125 	default:
1126 		error = 0;
1127 		break;
1128 	}
1129 	if (logflags)
1130 		xfs_trans_log_inode(tp, ip, logflags);
1131 	if (error)
1132 		goto bmap_cancel;
1133 	if (!xfs_sb_version_hasattr(&mp->m_sb) ||
1134 	   (!xfs_sb_version_hasattr2(&mp->m_sb) && version == 2)) {
1135 		bool log_sb = false;
1136 
1137 		spin_lock(&mp->m_sb_lock);
1138 		if (!xfs_sb_version_hasattr(&mp->m_sb)) {
1139 			xfs_sb_version_addattr(&mp->m_sb);
1140 			log_sb = true;
1141 		}
1142 		if (!xfs_sb_version_hasattr2(&mp->m_sb) && version == 2) {
1143 			xfs_sb_version_addattr2(&mp->m_sb);
1144 			log_sb = true;
1145 		}
1146 		spin_unlock(&mp->m_sb_lock);
1147 		if (log_sb)
1148 			xfs_log_sb(tp);
1149 	}
1150 
1151 	error = xfs_defer_finish(&tp, &dfops);
1152 	if (error)
1153 		goto bmap_cancel;
1154 	error = xfs_trans_commit(tp);
1155 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1156 	return error;
1157 
1158 bmap_cancel:
1159 	xfs_defer_cancel(&dfops);
1160 trans_cancel:
1161 	xfs_trans_cancel(tp);
1162 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1163 	return error;
1164 }
1165 
1166 /*
1167  * Internal and external extent tree search functions.
1168  */
1169 
1170 /*
1171  * Read in extents from a btree-format inode.
1172  */
1173 int
1174 xfs_iread_extents(
1175 	struct xfs_trans	*tp,
1176 	struct xfs_inode	*ip,
1177 	int			whichfork)
1178 {
1179 	struct xfs_mount	*mp = ip->i_mount;
1180 	int			state = xfs_bmap_fork_to_state(whichfork);
1181 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
1182 	xfs_extnum_t		nextents = XFS_IFORK_NEXTENTS(ip, whichfork);
1183 	struct xfs_btree_block	*block = ifp->if_broot;
1184 	struct xfs_iext_cursor	icur;
1185 	struct xfs_bmbt_irec	new;
1186 	xfs_fsblock_t		bno;
1187 	struct xfs_buf		*bp;
1188 	xfs_extnum_t		i, j;
1189 	int			level;
1190 	__be64			*pp;
1191 	int			error;
1192 
1193 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1194 
1195 	if (unlikely(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
1196 		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
1197 		return -EFSCORRUPTED;
1198 	}
1199 
1200 	/*
1201 	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
1202 	 */
1203 	level = be16_to_cpu(block->bb_level);
1204 	ASSERT(level > 0);
1205 	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
1206 	bno = be64_to_cpu(*pp);
1207 
1208 	/*
1209 	 * Go down the tree until leaf level is reached, following the first
1210 	 * pointer (leftmost) at each level.
1211 	 */
1212 	while (level-- > 0) {
1213 		error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
1214 				XFS_BMAP_BTREE_REF, &xfs_bmbt_buf_ops);
1215 		if (error)
1216 			goto out;
1217 		block = XFS_BUF_TO_BLOCK(bp);
1218 		if (level == 0)
1219 			break;
1220 		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
1221 		bno = be64_to_cpu(*pp);
1222 		XFS_WANT_CORRUPTED_GOTO(mp,
1223 			xfs_verify_fsbno(mp, bno), out_brelse);
1224 		xfs_trans_brelse(tp, bp);
1225 	}
1226 
1227 	/*
1228 	 * Here with bp and block set to the leftmost leaf node in the tree.
1229 	 */
1230 	i = 0;
1231 	xfs_iext_first(ifp, &icur);
1232 
1233 	/*
1234 	 * Loop over all leaf nodes.  Copy information to the extent records.
1235 	 */
1236 	for (;;) {
1237 		xfs_bmbt_rec_t	*frp;
1238 		xfs_fsblock_t	nextbno;
1239 		xfs_extnum_t	num_recs;
1240 
1241 		num_recs = xfs_btree_get_numrecs(block);
1242 		if (unlikely(i + num_recs > nextents)) {
1243 			ASSERT(i + num_recs <= nextents);
1244 			xfs_warn(ip->i_mount,
1245 				"corrupt dinode %Lu, (btree extents).",
1246 				(unsigned long long) ip->i_ino);
1247 			XFS_CORRUPTION_ERROR(__func__,
1248 				XFS_ERRLEVEL_LOW, ip->i_mount, block);
1249 			error = -EFSCORRUPTED;
1250 			goto out_brelse;
1251 		}
1252 		/*
1253 		 * Read-ahead the next leaf block, if any.
1254 		 */
1255 		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
1256 		if (nextbno != NULLFSBLOCK)
1257 			xfs_btree_reada_bufl(mp, nextbno, 1,
1258 					     &xfs_bmbt_buf_ops);
1259 		/*
1260 		 * Copy records into the extent records.
1261 		 */
1262 		frp = XFS_BMBT_REC_ADDR(mp, block, 1);
1263 		for (j = 0; j < num_recs; j++, frp++, i++) {
1264 			xfs_bmbt_disk_get_all(frp, &new);
1265 			if (!xfs_bmbt_validate_extent(mp, whichfork, &new)) {
1266 				XFS_ERROR_REPORT("xfs_bmap_read_extents(2)",
1267 						 XFS_ERRLEVEL_LOW, mp);
1268 				error = -EFSCORRUPTED;
1269 				goto out_brelse;
1270 			}
1271 			xfs_iext_insert(ip, &icur, &new, state);
1272 			trace_xfs_read_extent(ip, &icur, state, _THIS_IP_);
1273 			xfs_iext_next(ifp, &icur);
1274 		}
1275 		xfs_trans_brelse(tp, bp);
1276 		bno = nextbno;
1277 		/*
1278 		 * If we've reached the end, stop.
1279 		 */
1280 		if (bno == NULLFSBLOCK)
1281 			break;
1282 		error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
1283 				XFS_BMAP_BTREE_REF, &xfs_bmbt_buf_ops);
1284 		if (error)
1285 			goto out;
1286 		block = XFS_BUF_TO_BLOCK(bp);
1287 	}
1288 
1289 	if (i != XFS_IFORK_NEXTENTS(ip, whichfork)) {
1290 		error = -EFSCORRUPTED;
1291 		goto out;
1292 	}
1293 	ASSERT(i == xfs_iext_count(ifp));
1294 
1295 	ifp->if_flags |= XFS_IFEXTENTS;
1296 	return 0;
1297 
1298 out_brelse:
1299 	xfs_trans_brelse(tp, bp);
1300 out:
1301 	xfs_iext_destroy(ifp);
1302 	return error;
1303 }
1304 
1305 /*
1306  * Returns the relative block number of the first unused block(s) in the given
1307  * fork with at least "len" logically contiguous blocks free.  This is the
1308  * lowest-address hole if the fork has holes, else the first block past the end
1309  * of fork.  Return 0 if the fork is currently local (in-inode).
1310  */
1311 int						/* error */
1312 xfs_bmap_first_unused(
1313 	struct xfs_trans	*tp,		/* transaction pointer */
1314 	struct xfs_inode	*ip,		/* incore inode */
1315 	xfs_extlen_t		len,		/* size of hole to find */
1316 	xfs_fileoff_t		*first_unused,	/* unused block */
1317 	int			whichfork)	/* data or attr fork */
1318 {
1319 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
1320 	struct xfs_bmbt_irec	got;
1321 	struct xfs_iext_cursor	icur;
1322 	xfs_fileoff_t		lastaddr = 0;
1323 	xfs_fileoff_t		lowest, max;
1324 	int			error;
1325 
1326 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE ||
1327 	       XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ||
1328 	       XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
1329 
1330 	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
1331 		*first_unused = 0;
1332 		return 0;
1333 	}
1334 
1335 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
1336 		error = xfs_iread_extents(tp, ip, whichfork);
1337 		if (error)
1338 			return error;
1339 	}
1340 
1341 	lowest = max = *first_unused;
1342 	for_each_xfs_iext(ifp, &icur, &got) {
1343 		/*
1344 		 * See if the hole before this extent will work.
1345 		 */
1346 		if (got.br_startoff >= lowest + len &&
1347 		    got.br_startoff - max >= len)
1348 			break;
1349 		lastaddr = got.br_startoff + got.br_blockcount;
1350 		max = XFS_FILEOFF_MAX(lastaddr, lowest);
1351 	}
1352 
1353 	*first_unused = max;
1354 	return 0;
1355 }
1356 
1357 /*
1358  * Returns the file-relative block number of the last block - 1 before
1359  * last_block (input value) in the file.
1360  * This is not based on i_size, it is based on the extent records.
1361  * Returns 0 for local files, as they do not have extent records.
1362  */
1363 int						/* error */
1364 xfs_bmap_last_before(
1365 	struct xfs_trans	*tp,		/* transaction pointer */
1366 	struct xfs_inode	*ip,		/* incore inode */
1367 	xfs_fileoff_t		*last_block,	/* last block */
1368 	int			whichfork)	/* data or attr fork */
1369 {
1370 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
1371 	struct xfs_bmbt_irec	got;
1372 	struct xfs_iext_cursor	icur;
1373 	int			error;
1374 
1375 	switch (XFS_IFORK_FORMAT(ip, whichfork)) {
1376 	case XFS_DINODE_FMT_LOCAL:
1377 		*last_block = 0;
1378 		return 0;
1379 	case XFS_DINODE_FMT_BTREE:
1380 	case XFS_DINODE_FMT_EXTENTS:
1381 		break;
1382 	default:
1383 		return -EIO;
1384 	}
1385 
1386 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
1387 		error = xfs_iread_extents(tp, ip, whichfork);
1388 		if (error)
1389 			return error;
1390 	}
1391 
1392 	if (!xfs_iext_lookup_extent_before(ip, ifp, last_block, &icur, &got))
1393 		*last_block = 0;
1394 	return 0;
1395 }
1396 
1397 int
1398 xfs_bmap_last_extent(
1399 	struct xfs_trans	*tp,
1400 	struct xfs_inode	*ip,
1401 	int			whichfork,
1402 	struct xfs_bmbt_irec	*rec,
1403 	int			*is_empty)
1404 {
1405 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
1406 	struct xfs_iext_cursor	icur;
1407 	int			error;
1408 
1409 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
1410 		error = xfs_iread_extents(tp, ip, whichfork);
1411 		if (error)
1412 			return error;
1413 	}
1414 
1415 	xfs_iext_last(ifp, &icur);
1416 	if (!xfs_iext_get_extent(ifp, &icur, rec))
1417 		*is_empty = 1;
1418 	else
1419 		*is_empty = 0;
1420 	return 0;
1421 }
1422 
1423 /*
1424  * Check the last inode extent to determine whether this allocation will result
1425  * in blocks being allocated at the end of the file. When we allocate new data
1426  * blocks at the end of the file which do not start at the previous data block,
1427  * we will try to align the new blocks at stripe unit boundaries.
1428  *
1429  * Returns 1 in bma->aeof if the file (fork) is empty as any new write will be
1430  * at, or past the EOF.
1431  */
1432 STATIC int
1433 xfs_bmap_isaeof(
1434 	struct xfs_bmalloca	*bma,
1435 	int			whichfork)
1436 {
1437 	struct xfs_bmbt_irec	rec;
1438 	int			is_empty;
1439 	int			error;
1440 
1441 	bma->aeof = false;
1442 	error = xfs_bmap_last_extent(NULL, bma->ip, whichfork, &rec,
1443 				     &is_empty);
1444 	if (error)
1445 		return error;
1446 
1447 	if (is_empty) {
1448 		bma->aeof = true;
1449 		return 0;
1450 	}
1451 
1452 	/*
1453 	 * Check if we are allocation or past the last extent, or at least into
1454 	 * the last delayed allocated extent.
1455 	 */
1456 	bma->aeof = bma->offset >= rec.br_startoff + rec.br_blockcount ||
1457 		(bma->offset >= rec.br_startoff &&
1458 		 isnullstartblock(rec.br_startblock));
1459 	return 0;
1460 }
1461 
1462 /*
1463  * Returns the file-relative block number of the first block past eof in
1464  * the file.  This is not based on i_size, it is based on the extent records.
1465  * Returns 0 for local files, as they do not have extent records.
1466  */
1467 int
1468 xfs_bmap_last_offset(
1469 	struct xfs_inode	*ip,
1470 	xfs_fileoff_t		*last_block,
1471 	int			whichfork)
1472 {
1473 	struct xfs_bmbt_irec	rec;
1474 	int			is_empty;
1475 	int			error;
1476 
1477 	*last_block = 0;
1478 
1479 	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL)
1480 		return 0;
1481 
1482 	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
1483 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
1484 	       return -EIO;
1485 
1486 	error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, &is_empty);
1487 	if (error || is_empty)
1488 		return error;
1489 
1490 	*last_block = rec.br_startoff + rec.br_blockcount;
1491 	return 0;
1492 }
1493 
1494 /*
1495  * Returns whether the selected fork of the inode has exactly one
1496  * block or not.  For the data fork we check this matches di_size,
1497  * implying the file's range is 0..bsize-1.
1498  */
1499 int					/* 1=>1 block, 0=>otherwise */
1500 xfs_bmap_one_block(
1501 	xfs_inode_t	*ip,		/* incore inode */
1502 	int		whichfork)	/* data or attr fork */
1503 {
1504 	xfs_ifork_t	*ifp;		/* inode fork pointer */
1505 	int		rval;		/* return value */
1506 	xfs_bmbt_irec_t	s;		/* internal version of extent */
1507 	struct xfs_iext_cursor icur;
1508 
1509 #ifndef DEBUG
1510 	if (whichfork == XFS_DATA_FORK)
1511 		return XFS_ISIZE(ip) == ip->i_mount->m_sb.sb_blocksize;
1512 #endif	/* !DEBUG */
1513 	if (XFS_IFORK_NEXTENTS(ip, whichfork) != 1)
1514 		return 0;
1515 	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
1516 		return 0;
1517 	ifp = XFS_IFORK_PTR(ip, whichfork);
1518 	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
1519 	xfs_iext_first(ifp, &icur);
1520 	xfs_iext_get_extent(ifp, &icur, &s);
1521 	rval = s.br_startoff == 0 && s.br_blockcount == 1;
1522 	if (rval && whichfork == XFS_DATA_FORK)
1523 		ASSERT(XFS_ISIZE(ip) == ip->i_mount->m_sb.sb_blocksize);
1524 	return rval;
1525 }
1526 
1527 /*
1528  * Extent tree manipulation functions used during allocation.
1529  */
1530 
1531 /*
1532  * Convert a delayed allocation to a real allocation.
1533  */
1534 STATIC int				/* error */
1535 xfs_bmap_add_extent_delay_real(
1536 	struct xfs_bmalloca	*bma,
1537 	int			whichfork)
1538 {
1539 	struct xfs_bmbt_irec	*new = &bma->got;
1540 	int			error;	/* error return value */
1541 	int			i;	/* temp state */
1542 	xfs_ifork_t		*ifp;	/* inode fork pointer */
1543 	xfs_fileoff_t		new_endoff;	/* end offset of new entry */
1544 	xfs_bmbt_irec_t		r[3];	/* neighbor extent entries */
1545 					/* left is 0, right is 1, prev is 2 */
1546 	int			rval=0;	/* return value (logging flags) */
1547 	int			state = xfs_bmap_fork_to_state(whichfork);
1548 	xfs_filblks_t		da_new; /* new count del alloc blocks used */
1549 	xfs_filblks_t		da_old; /* old count del alloc blocks used */
1550 	xfs_filblks_t		temp=0;	/* value for da_new calculations */
1551 	int			tmp_rval;	/* partial logging flags */
1552 	struct xfs_mount	*mp;
1553 	xfs_extnum_t		*nextents;
1554 	struct xfs_bmbt_irec	old;
1555 
1556 	mp = bma->ip->i_mount;
1557 	ifp = XFS_IFORK_PTR(bma->ip, whichfork);
1558 	ASSERT(whichfork != XFS_ATTR_FORK);
1559 	nextents = (whichfork == XFS_COW_FORK ? &bma->ip->i_cnextents :
1560 						&bma->ip->i_d.di_nextents);
1561 
1562 	ASSERT(!isnullstartblock(new->br_startblock));
1563 	ASSERT(!bma->cur ||
1564 	       (bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
1565 
1566 	XFS_STATS_INC(mp, xs_add_exlist);
1567 
1568 #define	LEFT		r[0]
1569 #define	RIGHT		r[1]
1570 #define	PREV		r[2]
1571 
1572 	/*
1573 	 * Set up a bunch of variables to make the tests simpler.
1574 	 */
1575 	xfs_iext_get_extent(ifp, &bma->icur, &PREV);
1576 	new_endoff = new->br_startoff + new->br_blockcount;
1577 	ASSERT(isnullstartblock(PREV.br_startblock));
1578 	ASSERT(PREV.br_startoff <= new->br_startoff);
1579 	ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
1580 
1581 	da_old = startblockval(PREV.br_startblock);
1582 	da_new = 0;
1583 
1584 	/*
1585 	 * Set flags determining what part of the previous delayed allocation
1586 	 * extent is being replaced by a real allocation.
1587 	 */
1588 	if (PREV.br_startoff == new->br_startoff)
1589 		state |= BMAP_LEFT_FILLING;
1590 	if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
1591 		state |= BMAP_RIGHT_FILLING;
1592 
1593 	/*
1594 	 * Check and set flags if this segment has a left neighbor.
1595 	 * Don't set contiguous if the combined extent would be too large.
1596 	 */
1597 	if (xfs_iext_peek_prev_extent(ifp, &bma->icur, &LEFT)) {
1598 		state |= BMAP_LEFT_VALID;
1599 		if (isnullstartblock(LEFT.br_startblock))
1600 			state |= BMAP_LEFT_DELAY;
1601 	}
1602 
1603 	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
1604 	    LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
1605 	    LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
1606 	    LEFT.br_state == new->br_state &&
1607 	    LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
1608 		state |= BMAP_LEFT_CONTIG;
1609 
1610 	/*
1611 	 * Check and set flags if this segment has a right neighbor.
1612 	 * Don't set contiguous if the combined extent would be too large.
1613 	 * Also check for all-three-contiguous being too large.
1614 	 */
1615 	if (xfs_iext_peek_next_extent(ifp, &bma->icur, &RIGHT)) {
1616 		state |= BMAP_RIGHT_VALID;
1617 		if (isnullstartblock(RIGHT.br_startblock))
1618 			state |= BMAP_RIGHT_DELAY;
1619 	}
1620 
1621 	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
1622 	    new_endoff == RIGHT.br_startoff &&
1623 	    new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
1624 	    new->br_state == RIGHT.br_state &&
1625 	    new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
1626 	    ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1627 		       BMAP_RIGHT_FILLING)) !=
1628 		      (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1629 		       BMAP_RIGHT_FILLING) ||
1630 	     LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
1631 			<= MAXEXTLEN))
1632 		state |= BMAP_RIGHT_CONTIG;
1633 
1634 	error = 0;
1635 	/*
1636 	 * Switch out based on the FILLING and CONTIG state bits.
1637 	 */
1638 	switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1639 			 BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
1640 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1641 	     BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1642 		/*
1643 		 * Filling in all of a previously delayed allocation extent.
1644 		 * The left and right neighbors are both contiguous with new.
1645 		 */
1646 		LEFT.br_blockcount += PREV.br_blockcount + RIGHT.br_blockcount;
1647 
1648 		xfs_iext_remove(bma->ip, &bma->icur, state);
1649 		xfs_iext_remove(bma->ip, &bma->icur, state);
1650 		xfs_iext_prev(ifp, &bma->icur);
1651 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1652 		(*nextents)--;
1653 
1654 		if (bma->cur == NULL)
1655 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1656 		else {
1657 			rval = XFS_ILOG_CORE;
1658 			error = xfs_bmbt_lookup_eq(bma->cur, &RIGHT, &i);
1659 			if (error)
1660 				goto done;
1661 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1662 			error = xfs_btree_delete(bma->cur, &i);
1663 			if (error)
1664 				goto done;
1665 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1666 			error = xfs_btree_decrement(bma->cur, 0, &i);
1667 			if (error)
1668 				goto done;
1669 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1670 			error = xfs_bmbt_update(bma->cur, &LEFT);
1671 			if (error)
1672 				goto done;
1673 		}
1674 		break;
1675 
1676 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1677 		/*
1678 		 * Filling in all of a previously delayed allocation extent.
1679 		 * The left neighbor is contiguous, the right is not.
1680 		 */
1681 		old = LEFT;
1682 		LEFT.br_blockcount += PREV.br_blockcount;
1683 
1684 		xfs_iext_remove(bma->ip, &bma->icur, state);
1685 		xfs_iext_prev(ifp, &bma->icur);
1686 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1687 
1688 		if (bma->cur == NULL)
1689 			rval = XFS_ILOG_DEXT;
1690 		else {
1691 			rval = 0;
1692 			error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1693 			if (error)
1694 				goto done;
1695 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1696 			error = xfs_bmbt_update(bma->cur, &LEFT);
1697 			if (error)
1698 				goto done;
1699 		}
1700 		break;
1701 
1702 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1703 		/*
1704 		 * Filling in all of a previously delayed allocation extent.
1705 		 * The right neighbor is contiguous, the left is not.
1706 		 */
1707 		PREV.br_startblock = new->br_startblock;
1708 		PREV.br_blockcount += RIGHT.br_blockcount;
1709 
1710 		xfs_iext_next(ifp, &bma->icur);
1711 		xfs_iext_remove(bma->ip, &bma->icur, state);
1712 		xfs_iext_prev(ifp, &bma->icur);
1713 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1714 
1715 		if (bma->cur == NULL)
1716 			rval = XFS_ILOG_DEXT;
1717 		else {
1718 			rval = 0;
1719 			error = xfs_bmbt_lookup_eq(bma->cur, &RIGHT, &i);
1720 			if (error)
1721 				goto done;
1722 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1723 			error = xfs_bmbt_update(bma->cur, &PREV);
1724 			if (error)
1725 				goto done;
1726 		}
1727 		break;
1728 
1729 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
1730 		/*
1731 		 * Filling in all of a previously delayed allocation extent.
1732 		 * Neither the left nor right neighbors are contiguous with
1733 		 * the new one.
1734 		 */
1735 		PREV.br_startblock = new->br_startblock;
1736 		PREV.br_state = new->br_state;
1737 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1738 
1739 		(*nextents)++;
1740 		if (bma->cur == NULL)
1741 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1742 		else {
1743 			rval = XFS_ILOG_CORE;
1744 			error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1745 			if (error)
1746 				goto done;
1747 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
1748 			error = xfs_btree_insert(bma->cur, &i);
1749 			if (error)
1750 				goto done;
1751 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1752 		}
1753 		break;
1754 
1755 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
1756 		/*
1757 		 * Filling in the first part of a previous delayed allocation.
1758 		 * The left neighbor is contiguous.
1759 		 */
1760 		old = LEFT;
1761 		temp = PREV.br_blockcount - new->br_blockcount;
1762 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1763 				startblockval(PREV.br_startblock));
1764 
1765 		LEFT.br_blockcount += new->br_blockcount;
1766 
1767 		PREV.br_blockcount = temp;
1768 		PREV.br_startoff += new->br_blockcount;
1769 		PREV.br_startblock = nullstartblock(da_new);
1770 
1771 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1772 		xfs_iext_prev(ifp, &bma->icur);
1773 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1774 
1775 		if (bma->cur == NULL)
1776 			rval = XFS_ILOG_DEXT;
1777 		else {
1778 			rval = 0;
1779 			error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1780 			if (error)
1781 				goto done;
1782 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1783 			error = xfs_bmbt_update(bma->cur, &LEFT);
1784 			if (error)
1785 				goto done;
1786 		}
1787 		break;
1788 
1789 	case BMAP_LEFT_FILLING:
1790 		/*
1791 		 * Filling in the first part of a previous delayed allocation.
1792 		 * The left neighbor is not contiguous.
1793 		 */
1794 		xfs_iext_update_extent(bma->ip, state, &bma->icur, new);
1795 		(*nextents)++;
1796 		if (bma->cur == NULL)
1797 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1798 		else {
1799 			rval = XFS_ILOG_CORE;
1800 			error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1801 			if (error)
1802 				goto done;
1803 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
1804 			error = xfs_btree_insert(bma->cur, &i);
1805 			if (error)
1806 				goto done;
1807 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1808 		}
1809 
1810 		if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1811 			error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1812 					bma->firstblock, bma->dfops,
1813 					&bma->cur, 1, &tmp_rval, whichfork);
1814 			rval |= tmp_rval;
1815 			if (error)
1816 				goto done;
1817 		}
1818 
1819 		temp = PREV.br_blockcount - new->br_blockcount;
1820 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1821 			startblockval(PREV.br_startblock) -
1822 			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
1823 
1824 		PREV.br_startoff = new_endoff;
1825 		PREV.br_blockcount = temp;
1826 		PREV.br_startblock = nullstartblock(da_new);
1827 		xfs_iext_next(ifp, &bma->icur);
1828 		xfs_iext_insert(bma->ip, &bma->icur, &PREV, state);
1829 		xfs_iext_prev(ifp, &bma->icur);
1830 		break;
1831 
1832 	case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1833 		/*
1834 		 * Filling in the last part of a previous delayed allocation.
1835 		 * The right neighbor is contiguous with the new allocation.
1836 		 */
1837 		old = RIGHT;
1838 		RIGHT.br_startoff = new->br_startoff;
1839 		RIGHT.br_startblock = new->br_startblock;
1840 		RIGHT.br_blockcount += new->br_blockcount;
1841 
1842 		if (bma->cur == NULL)
1843 			rval = XFS_ILOG_DEXT;
1844 		else {
1845 			rval = 0;
1846 			error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1847 			if (error)
1848 				goto done;
1849 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1850 			error = xfs_bmbt_update(bma->cur, &RIGHT);
1851 			if (error)
1852 				goto done;
1853 		}
1854 
1855 		temp = PREV.br_blockcount - new->br_blockcount;
1856 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1857 			startblockval(PREV.br_startblock));
1858 
1859 		PREV.br_blockcount = temp;
1860 		PREV.br_startblock = nullstartblock(da_new);
1861 
1862 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1863 		xfs_iext_next(ifp, &bma->icur);
1864 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &RIGHT);
1865 		break;
1866 
1867 	case BMAP_RIGHT_FILLING:
1868 		/*
1869 		 * Filling in the last part of a previous delayed allocation.
1870 		 * The right neighbor is not contiguous.
1871 		 */
1872 		xfs_iext_update_extent(bma->ip, state, &bma->icur, new);
1873 		(*nextents)++;
1874 		if (bma->cur == NULL)
1875 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1876 		else {
1877 			rval = XFS_ILOG_CORE;
1878 			error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1879 			if (error)
1880 				goto done;
1881 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
1882 			error = xfs_btree_insert(bma->cur, &i);
1883 			if (error)
1884 				goto done;
1885 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1886 		}
1887 
1888 		if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1889 			error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1890 				bma->firstblock, bma->dfops, &bma->cur, 1,
1891 				&tmp_rval, whichfork);
1892 			rval |= tmp_rval;
1893 			if (error)
1894 				goto done;
1895 		}
1896 
1897 		temp = PREV.br_blockcount - new->br_blockcount;
1898 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1899 			startblockval(PREV.br_startblock) -
1900 			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
1901 
1902 		PREV.br_startblock = nullstartblock(da_new);
1903 		PREV.br_blockcount = temp;
1904 		xfs_iext_insert(bma->ip, &bma->icur, &PREV, state);
1905 		xfs_iext_next(ifp, &bma->icur);
1906 		break;
1907 
1908 	case 0:
1909 		/*
1910 		 * Filling in the middle part of a previous delayed allocation.
1911 		 * Contiguity is impossible here.
1912 		 * This case is avoided almost all the time.
1913 		 *
1914 		 * We start with a delayed allocation:
1915 		 *
1916 		 * +ddddddddddddddddddddddddddddddddddddddddddddddddddddddd+
1917 		 *  PREV @ idx
1918 		 *
1919 	         * and we are allocating:
1920 		 *                     +rrrrrrrrrrrrrrrrr+
1921 		 *			      new
1922 		 *
1923 		 * and we set it up for insertion as:
1924 		 * +ddddddddddddddddddd+rrrrrrrrrrrrrrrrr+ddddddddddddddddd+
1925 		 *                            new
1926 		 *  PREV @ idx          LEFT              RIGHT
1927 		 *                      inserted at idx + 1
1928 		 */
1929 		old = PREV;
1930 
1931 		/* LEFT is the new middle */
1932 		LEFT = *new;
1933 
1934 		/* RIGHT is the new right */
1935 		RIGHT.br_state = PREV.br_state;
1936 		RIGHT.br_startoff = new_endoff;
1937 		RIGHT.br_blockcount =
1938 			PREV.br_startoff + PREV.br_blockcount - new_endoff;
1939 		RIGHT.br_startblock =
1940 			nullstartblock(xfs_bmap_worst_indlen(bma->ip,
1941 					RIGHT.br_blockcount));
1942 
1943 		/* truncate PREV */
1944 		PREV.br_blockcount = new->br_startoff - PREV.br_startoff;
1945 		PREV.br_startblock =
1946 			nullstartblock(xfs_bmap_worst_indlen(bma->ip,
1947 					PREV.br_blockcount));
1948 		xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1949 
1950 		xfs_iext_next(ifp, &bma->icur);
1951 		xfs_iext_insert(bma->ip, &bma->icur, &RIGHT, state);
1952 		xfs_iext_insert(bma->ip, &bma->icur, &LEFT, state);
1953 		(*nextents)++;
1954 
1955 		if (bma->cur == NULL)
1956 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1957 		else {
1958 			rval = XFS_ILOG_CORE;
1959 			error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1960 			if (error)
1961 				goto done;
1962 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
1963 			error = xfs_btree_insert(bma->cur, &i);
1964 			if (error)
1965 				goto done;
1966 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1967 		}
1968 
1969 		if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1970 			error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1971 					bma->firstblock, bma->dfops, &bma->cur,
1972 					1, &tmp_rval, whichfork);
1973 			rval |= tmp_rval;
1974 			if (error)
1975 				goto done;
1976 		}
1977 
1978 		da_new = startblockval(PREV.br_startblock) +
1979 			 startblockval(RIGHT.br_startblock);
1980 		break;
1981 
1982 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1983 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1984 	case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
1985 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1986 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1987 	case BMAP_LEFT_CONTIG:
1988 	case BMAP_RIGHT_CONTIG:
1989 		/*
1990 		 * These cases are all impossible.
1991 		 */
1992 		ASSERT(0);
1993 	}
1994 
1995 	/* add reverse mapping */
1996 	error = xfs_rmap_map_extent(mp, bma->dfops, bma->ip, whichfork, new);
1997 	if (error)
1998 		goto done;
1999 
2000 	/* convert to a btree if necessary */
2001 	if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
2002 		int	tmp_logflags;	/* partial log flag return val */
2003 
2004 		ASSERT(bma->cur == NULL);
2005 		error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
2006 				bma->firstblock, bma->dfops, &bma->cur,
2007 				da_old > 0, &tmp_logflags, whichfork);
2008 		bma->logflags |= tmp_logflags;
2009 		if (error)
2010 			goto done;
2011 	}
2012 
2013 	if (bma->cur) {
2014 		da_new += bma->cur->bc_private.b.allocated;
2015 		bma->cur->bc_private.b.allocated = 0;
2016 	}
2017 
2018 	/* adjust for changes in reserved delayed indirect blocks */
2019 	if (da_new != da_old) {
2020 		ASSERT(state == 0 || da_new < da_old);
2021 		error = xfs_mod_fdblocks(mp, (int64_t)(da_old - da_new),
2022 				false);
2023 	}
2024 
2025 	xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
2026 done:
2027 	if (whichfork != XFS_COW_FORK)
2028 		bma->logflags |= rval;
2029 	return error;
2030 #undef	LEFT
2031 #undef	RIGHT
2032 #undef	PREV
2033 }
2034 
2035 /*
2036  * Convert an unwritten allocation to a real allocation or vice versa.
2037  */
2038 STATIC int				/* error */
2039 xfs_bmap_add_extent_unwritten_real(
2040 	struct xfs_trans	*tp,
2041 	xfs_inode_t		*ip,	/* incore inode pointer */
2042 	int			whichfork,
2043 	struct xfs_iext_cursor	*icur,
2044 	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
2045 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
2046 	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
2047 	struct xfs_defer_ops	*dfops,	/* list of extents to be freed */
2048 	int			*logflagsp) /* inode logging flags */
2049 {
2050 	xfs_btree_cur_t		*cur;	/* btree cursor */
2051 	int			error;	/* error return value */
2052 	int			i;	/* temp state */
2053 	xfs_ifork_t		*ifp;	/* inode fork pointer */
2054 	xfs_fileoff_t		new_endoff;	/* end offset of new entry */
2055 	xfs_bmbt_irec_t		r[3];	/* neighbor extent entries */
2056 					/* left is 0, right is 1, prev is 2 */
2057 	int			rval=0;	/* return value (logging flags) */
2058 	int			state = xfs_bmap_fork_to_state(whichfork);
2059 	struct xfs_mount	*mp = ip->i_mount;
2060 	struct xfs_bmbt_irec	old;
2061 
2062 	*logflagsp = 0;
2063 
2064 	cur = *curp;
2065 	ifp = XFS_IFORK_PTR(ip, whichfork);
2066 
2067 	ASSERT(!isnullstartblock(new->br_startblock));
2068 
2069 	XFS_STATS_INC(mp, xs_add_exlist);
2070 
2071 #define	LEFT		r[0]
2072 #define	RIGHT		r[1]
2073 #define	PREV		r[2]
2074 
2075 	/*
2076 	 * Set up a bunch of variables to make the tests simpler.
2077 	 */
2078 	error = 0;
2079 	xfs_iext_get_extent(ifp, icur, &PREV);
2080 	ASSERT(new->br_state != PREV.br_state);
2081 	new_endoff = new->br_startoff + new->br_blockcount;
2082 	ASSERT(PREV.br_startoff <= new->br_startoff);
2083 	ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
2084 
2085 	/*
2086 	 * Set flags determining what part of the previous oldext allocation
2087 	 * extent is being replaced by a newext allocation.
2088 	 */
2089 	if (PREV.br_startoff == new->br_startoff)
2090 		state |= BMAP_LEFT_FILLING;
2091 	if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
2092 		state |= BMAP_RIGHT_FILLING;
2093 
2094 	/*
2095 	 * Check and set flags if this segment has a left neighbor.
2096 	 * Don't set contiguous if the combined extent would be too large.
2097 	 */
2098 	if (xfs_iext_peek_prev_extent(ifp, icur, &LEFT)) {
2099 		state |= BMAP_LEFT_VALID;
2100 		if (isnullstartblock(LEFT.br_startblock))
2101 			state |= BMAP_LEFT_DELAY;
2102 	}
2103 
2104 	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
2105 	    LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
2106 	    LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
2107 	    LEFT.br_state == new->br_state &&
2108 	    LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2109 		state |= BMAP_LEFT_CONTIG;
2110 
2111 	/*
2112 	 * Check and set flags if this segment has a right neighbor.
2113 	 * Don't set contiguous if the combined extent would be too large.
2114 	 * Also check for all-three-contiguous being too large.
2115 	 */
2116 	if (xfs_iext_peek_next_extent(ifp, icur, &RIGHT)) {
2117 		state |= BMAP_RIGHT_VALID;
2118 		if (isnullstartblock(RIGHT.br_startblock))
2119 			state |= BMAP_RIGHT_DELAY;
2120 	}
2121 
2122 	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
2123 	    new_endoff == RIGHT.br_startoff &&
2124 	    new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
2125 	    new->br_state == RIGHT.br_state &&
2126 	    new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
2127 	    ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2128 		       BMAP_RIGHT_FILLING)) !=
2129 		      (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2130 		       BMAP_RIGHT_FILLING) ||
2131 	     LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
2132 			<= MAXEXTLEN))
2133 		state |= BMAP_RIGHT_CONTIG;
2134 
2135 	/*
2136 	 * Switch out based on the FILLING and CONTIG state bits.
2137 	 */
2138 	switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2139 			 BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
2140 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2141 	     BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2142 		/*
2143 		 * Setting all of a previous oldext extent to newext.
2144 		 * The left and right neighbors are both contiguous with new.
2145 		 */
2146 		LEFT.br_blockcount += PREV.br_blockcount + RIGHT.br_blockcount;
2147 
2148 		xfs_iext_remove(ip, icur, state);
2149 		xfs_iext_remove(ip, icur, state);
2150 		xfs_iext_prev(ifp, icur);
2151 		xfs_iext_update_extent(ip, state, icur, &LEFT);
2152 		XFS_IFORK_NEXT_SET(ip, whichfork,
2153 				XFS_IFORK_NEXTENTS(ip, whichfork) - 2);
2154 		if (cur == NULL)
2155 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2156 		else {
2157 			rval = XFS_ILOG_CORE;
2158 			error = xfs_bmbt_lookup_eq(cur, &RIGHT, &i);
2159 			if (error)
2160 				goto done;
2161 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2162 			if ((error = xfs_btree_delete(cur, &i)))
2163 				goto done;
2164 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2165 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2166 				goto done;
2167 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2168 			if ((error = xfs_btree_delete(cur, &i)))
2169 				goto done;
2170 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2171 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2172 				goto done;
2173 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2174 			error = xfs_bmbt_update(cur, &LEFT);
2175 			if (error)
2176 				goto done;
2177 		}
2178 		break;
2179 
2180 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2181 		/*
2182 		 * Setting all of a previous oldext extent to newext.
2183 		 * The left neighbor is contiguous, the right is not.
2184 		 */
2185 		LEFT.br_blockcount += PREV.br_blockcount;
2186 
2187 		xfs_iext_remove(ip, icur, state);
2188 		xfs_iext_prev(ifp, icur);
2189 		xfs_iext_update_extent(ip, state, icur, &LEFT);
2190 		XFS_IFORK_NEXT_SET(ip, whichfork,
2191 				XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
2192 		if (cur == NULL)
2193 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2194 		else {
2195 			rval = XFS_ILOG_CORE;
2196 			error = xfs_bmbt_lookup_eq(cur, &PREV, &i);
2197 			if (error)
2198 				goto done;
2199 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2200 			if ((error = xfs_btree_delete(cur, &i)))
2201 				goto done;
2202 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2203 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2204 				goto done;
2205 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2206 			error = xfs_bmbt_update(cur, &LEFT);
2207 			if (error)
2208 				goto done;
2209 		}
2210 		break;
2211 
2212 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2213 		/*
2214 		 * Setting all of a previous oldext extent to newext.
2215 		 * The right neighbor is contiguous, the left is not.
2216 		 */
2217 		PREV.br_blockcount += RIGHT.br_blockcount;
2218 		PREV.br_state = new->br_state;
2219 
2220 		xfs_iext_next(ifp, icur);
2221 		xfs_iext_remove(ip, icur, state);
2222 		xfs_iext_prev(ifp, icur);
2223 		xfs_iext_update_extent(ip, state, icur, &PREV);
2224 
2225 		XFS_IFORK_NEXT_SET(ip, whichfork,
2226 				XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
2227 		if (cur == NULL)
2228 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2229 		else {
2230 			rval = XFS_ILOG_CORE;
2231 			error = xfs_bmbt_lookup_eq(cur, &RIGHT, &i);
2232 			if (error)
2233 				goto done;
2234 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2235 			if ((error = xfs_btree_delete(cur, &i)))
2236 				goto done;
2237 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2238 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2239 				goto done;
2240 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2241 			error = xfs_bmbt_update(cur, &PREV);
2242 			if (error)
2243 				goto done;
2244 		}
2245 		break;
2246 
2247 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
2248 		/*
2249 		 * Setting all of a previous oldext extent to newext.
2250 		 * Neither the left nor right neighbors are contiguous with
2251 		 * the new one.
2252 		 */
2253 		PREV.br_state = new->br_state;
2254 		xfs_iext_update_extent(ip, state, icur, &PREV);
2255 
2256 		if (cur == NULL)
2257 			rval = XFS_ILOG_DEXT;
2258 		else {
2259 			rval = 0;
2260 			error = xfs_bmbt_lookup_eq(cur, new, &i);
2261 			if (error)
2262 				goto done;
2263 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2264 			error = xfs_bmbt_update(cur, &PREV);
2265 			if (error)
2266 				goto done;
2267 		}
2268 		break;
2269 
2270 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
2271 		/*
2272 		 * Setting the first part of a previous oldext extent to newext.
2273 		 * The left neighbor is contiguous.
2274 		 */
2275 		LEFT.br_blockcount += new->br_blockcount;
2276 
2277 		old = PREV;
2278 		PREV.br_startoff += new->br_blockcount;
2279 		PREV.br_startblock += new->br_blockcount;
2280 		PREV.br_blockcount -= new->br_blockcount;
2281 
2282 		xfs_iext_update_extent(ip, state, icur, &PREV);
2283 		xfs_iext_prev(ifp, icur);
2284 		xfs_iext_update_extent(ip, state, icur, &LEFT);
2285 
2286 		if (cur == NULL)
2287 			rval = XFS_ILOG_DEXT;
2288 		else {
2289 			rval = 0;
2290 			error = xfs_bmbt_lookup_eq(cur, &old, &i);
2291 			if (error)
2292 				goto done;
2293 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2294 			error = xfs_bmbt_update(cur, &PREV);
2295 			if (error)
2296 				goto done;
2297 			error = xfs_btree_decrement(cur, 0, &i);
2298 			if (error)
2299 				goto done;
2300 			error = xfs_bmbt_update(cur, &LEFT);
2301 			if (error)
2302 				goto done;
2303 		}
2304 		break;
2305 
2306 	case BMAP_LEFT_FILLING:
2307 		/*
2308 		 * Setting the first part of a previous oldext extent to newext.
2309 		 * The left neighbor is not contiguous.
2310 		 */
2311 		old = PREV;
2312 		PREV.br_startoff += new->br_blockcount;
2313 		PREV.br_startblock += new->br_blockcount;
2314 		PREV.br_blockcount -= new->br_blockcount;
2315 
2316 		xfs_iext_update_extent(ip, state, icur, &PREV);
2317 		xfs_iext_insert(ip, icur, new, state);
2318 		XFS_IFORK_NEXT_SET(ip, whichfork,
2319 				XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
2320 		if (cur == NULL)
2321 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2322 		else {
2323 			rval = XFS_ILOG_CORE;
2324 			error = xfs_bmbt_lookup_eq(cur, &old, &i);
2325 			if (error)
2326 				goto done;
2327 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2328 			error = xfs_bmbt_update(cur, &PREV);
2329 			if (error)
2330 				goto done;
2331 			cur->bc_rec.b = *new;
2332 			if ((error = xfs_btree_insert(cur, &i)))
2333 				goto done;
2334 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2335 		}
2336 		break;
2337 
2338 	case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2339 		/*
2340 		 * Setting the last part of a previous oldext extent to newext.
2341 		 * The right neighbor is contiguous with the new allocation.
2342 		 */
2343 		old = PREV;
2344 		PREV.br_blockcount -= new->br_blockcount;
2345 
2346 		RIGHT.br_startoff = new->br_startoff;
2347 		RIGHT.br_startblock = new->br_startblock;
2348 		RIGHT.br_blockcount += new->br_blockcount;
2349 
2350 		xfs_iext_update_extent(ip, state, icur, &PREV);
2351 		xfs_iext_next(ifp, icur);
2352 		xfs_iext_update_extent(ip, state, icur, &RIGHT);
2353 
2354 		if (cur == NULL)
2355 			rval = XFS_ILOG_DEXT;
2356 		else {
2357 			rval = 0;
2358 			error = xfs_bmbt_lookup_eq(cur, &old, &i);
2359 			if (error)
2360 				goto done;
2361 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2362 			error = xfs_bmbt_update(cur, &PREV);
2363 			if (error)
2364 				goto done;
2365 			error = xfs_btree_increment(cur, 0, &i);
2366 			if (error)
2367 				goto done;
2368 			error = xfs_bmbt_update(cur, &RIGHT);
2369 			if (error)
2370 				goto done;
2371 		}
2372 		break;
2373 
2374 	case BMAP_RIGHT_FILLING:
2375 		/*
2376 		 * Setting the last part of a previous oldext extent to newext.
2377 		 * The right neighbor is not contiguous.
2378 		 */
2379 		old = PREV;
2380 		PREV.br_blockcount -= new->br_blockcount;
2381 
2382 		xfs_iext_update_extent(ip, state, icur, &PREV);
2383 		xfs_iext_next(ifp, icur);
2384 		xfs_iext_insert(ip, icur, new, state);
2385 
2386 		XFS_IFORK_NEXT_SET(ip, whichfork,
2387 				XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
2388 		if (cur == NULL)
2389 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2390 		else {
2391 			rval = XFS_ILOG_CORE;
2392 			error = xfs_bmbt_lookup_eq(cur, &old, &i);
2393 			if (error)
2394 				goto done;
2395 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2396 			error = xfs_bmbt_update(cur, &PREV);
2397 			if (error)
2398 				goto done;
2399 			error = xfs_bmbt_lookup_eq(cur, new, &i);
2400 			if (error)
2401 				goto done;
2402 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2403 			if ((error = xfs_btree_insert(cur, &i)))
2404 				goto done;
2405 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2406 		}
2407 		break;
2408 
2409 	case 0:
2410 		/*
2411 		 * Setting the middle part of a previous oldext extent to
2412 		 * newext.  Contiguity is impossible here.
2413 		 * One extent becomes three extents.
2414 		 */
2415 		old = PREV;
2416 		PREV.br_blockcount = new->br_startoff - PREV.br_startoff;
2417 
2418 		r[0] = *new;
2419 		r[1].br_startoff = new_endoff;
2420 		r[1].br_blockcount =
2421 			old.br_startoff + old.br_blockcount - new_endoff;
2422 		r[1].br_startblock = new->br_startblock + new->br_blockcount;
2423 		r[1].br_state = PREV.br_state;
2424 
2425 		xfs_iext_update_extent(ip, state, icur, &PREV);
2426 		xfs_iext_next(ifp, icur);
2427 		xfs_iext_insert(ip, icur, &r[1], state);
2428 		xfs_iext_insert(ip, icur, &r[0], state);
2429 
2430 		XFS_IFORK_NEXT_SET(ip, whichfork,
2431 				XFS_IFORK_NEXTENTS(ip, whichfork) + 2);
2432 		if (cur == NULL)
2433 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2434 		else {
2435 			rval = XFS_ILOG_CORE;
2436 			error = xfs_bmbt_lookup_eq(cur, &old, &i);
2437 			if (error)
2438 				goto done;
2439 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2440 			/* new right extent - oldext */
2441 			error = xfs_bmbt_update(cur, &r[1]);
2442 			if (error)
2443 				goto done;
2444 			/* new left extent - oldext */
2445 			cur->bc_rec.b = PREV;
2446 			if ((error = xfs_btree_insert(cur, &i)))
2447 				goto done;
2448 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2449 			/*
2450 			 * Reset the cursor to the position of the new extent
2451 			 * we are about to insert as we can't trust it after
2452 			 * the previous insert.
2453 			 */
2454 			error = xfs_bmbt_lookup_eq(cur, new, &i);
2455 			if (error)
2456 				goto done;
2457 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2458 			/* new middle extent - newext */
2459 			if ((error = xfs_btree_insert(cur, &i)))
2460 				goto done;
2461 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2462 		}
2463 		break;
2464 
2465 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2466 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2467 	case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
2468 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2469 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2470 	case BMAP_LEFT_CONTIG:
2471 	case BMAP_RIGHT_CONTIG:
2472 		/*
2473 		 * These cases are all impossible.
2474 		 */
2475 		ASSERT(0);
2476 	}
2477 
2478 	/* update reverse mappings */
2479 	error = xfs_rmap_convert_extent(mp, dfops, ip, whichfork, new);
2480 	if (error)
2481 		goto done;
2482 
2483 	/* convert to a btree if necessary */
2484 	if (xfs_bmap_needs_btree(ip, whichfork)) {
2485 		int	tmp_logflags;	/* partial log flag return val */
2486 
2487 		ASSERT(cur == NULL);
2488 		error = xfs_bmap_extents_to_btree(tp, ip, first, dfops, &cur,
2489 				0, &tmp_logflags, whichfork);
2490 		*logflagsp |= tmp_logflags;
2491 		if (error)
2492 			goto done;
2493 	}
2494 
2495 	/* clear out the allocated field, done with it now in any case. */
2496 	if (cur) {
2497 		cur->bc_private.b.allocated = 0;
2498 		*curp = cur;
2499 	}
2500 
2501 	xfs_bmap_check_leaf_extents(*curp, ip, whichfork);
2502 done:
2503 	*logflagsp |= rval;
2504 	return error;
2505 #undef	LEFT
2506 #undef	RIGHT
2507 #undef	PREV
2508 }
2509 
2510 /*
2511  * Convert a hole to a delayed allocation.
2512  */
2513 STATIC void
2514 xfs_bmap_add_extent_hole_delay(
2515 	xfs_inode_t		*ip,	/* incore inode pointer */
2516 	int			whichfork,
2517 	struct xfs_iext_cursor	*icur,
2518 	xfs_bmbt_irec_t		*new)	/* new data to add to file extents */
2519 {
2520 	xfs_ifork_t		*ifp;	/* inode fork pointer */
2521 	xfs_bmbt_irec_t		left;	/* left neighbor extent entry */
2522 	xfs_filblks_t		newlen=0;	/* new indirect size */
2523 	xfs_filblks_t		oldlen=0;	/* old indirect size */
2524 	xfs_bmbt_irec_t		right;	/* right neighbor extent entry */
2525 	int			state = xfs_bmap_fork_to_state(whichfork);
2526 	xfs_filblks_t		temp;	 /* temp for indirect calculations */
2527 
2528 	ifp = XFS_IFORK_PTR(ip, whichfork);
2529 	ASSERT(isnullstartblock(new->br_startblock));
2530 
2531 	/*
2532 	 * Check and set flags if this segment has a left neighbor
2533 	 */
2534 	if (xfs_iext_peek_prev_extent(ifp, icur, &left)) {
2535 		state |= BMAP_LEFT_VALID;
2536 		if (isnullstartblock(left.br_startblock))
2537 			state |= BMAP_LEFT_DELAY;
2538 	}
2539 
2540 	/*
2541 	 * Check and set flags if the current (right) segment exists.
2542 	 * If it doesn't exist, we're converting the hole at end-of-file.
2543 	 */
2544 	if (xfs_iext_get_extent(ifp, icur, &right)) {
2545 		state |= BMAP_RIGHT_VALID;
2546 		if (isnullstartblock(right.br_startblock))
2547 			state |= BMAP_RIGHT_DELAY;
2548 	}
2549 
2550 	/*
2551 	 * Set contiguity flags on the left and right neighbors.
2552 	 * Don't let extents get too large, even if the pieces are contiguous.
2553 	 */
2554 	if ((state & BMAP_LEFT_VALID) && (state & BMAP_LEFT_DELAY) &&
2555 	    left.br_startoff + left.br_blockcount == new->br_startoff &&
2556 	    left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2557 		state |= BMAP_LEFT_CONTIG;
2558 
2559 	if ((state & BMAP_RIGHT_VALID) && (state & BMAP_RIGHT_DELAY) &&
2560 	    new->br_startoff + new->br_blockcount == right.br_startoff &&
2561 	    new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
2562 	    (!(state & BMAP_LEFT_CONTIG) ||
2563 	     (left.br_blockcount + new->br_blockcount +
2564 	      right.br_blockcount <= MAXEXTLEN)))
2565 		state |= BMAP_RIGHT_CONTIG;
2566 
2567 	/*
2568 	 * Switch out based on the contiguity flags.
2569 	 */
2570 	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
2571 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2572 		/*
2573 		 * New allocation is contiguous with delayed allocations
2574 		 * on the left and on the right.
2575 		 * Merge all three into a single extent record.
2576 		 */
2577 		temp = left.br_blockcount + new->br_blockcount +
2578 			right.br_blockcount;
2579 
2580 		oldlen = startblockval(left.br_startblock) +
2581 			startblockval(new->br_startblock) +
2582 			startblockval(right.br_startblock);
2583 		newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2584 					 oldlen);
2585 		left.br_startblock = nullstartblock(newlen);
2586 		left.br_blockcount = temp;
2587 
2588 		xfs_iext_remove(ip, icur, state);
2589 		xfs_iext_prev(ifp, icur);
2590 		xfs_iext_update_extent(ip, state, icur, &left);
2591 		break;
2592 
2593 	case BMAP_LEFT_CONTIG:
2594 		/*
2595 		 * New allocation is contiguous with a delayed allocation
2596 		 * on the left.
2597 		 * Merge the new allocation with the left neighbor.
2598 		 */
2599 		temp = left.br_blockcount + new->br_blockcount;
2600 
2601 		oldlen = startblockval(left.br_startblock) +
2602 			startblockval(new->br_startblock);
2603 		newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2604 					 oldlen);
2605 		left.br_blockcount = temp;
2606 		left.br_startblock = nullstartblock(newlen);
2607 
2608 		xfs_iext_prev(ifp, icur);
2609 		xfs_iext_update_extent(ip, state, icur, &left);
2610 		break;
2611 
2612 	case BMAP_RIGHT_CONTIG:
2613 		/*
2614 		 * New allocation is contiguous with a delayed allocation
2615 		 * on the right.
2616 		 * Merge the new allocation with the right neighbor.
2617 		 */
2618 		temp = new->br_blockcount + right.br_blockcount;
2619 		oldlen = startblockval(new->br_startblock) +
2620 			startblockval(right.br_startblock);
2621 		newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2622 					 oldlen);
2623 		right.br_startoff = new->br_startoff;
2624 		right.br_startblock = nullstartblock(newlen);
2625 		right.br_blockcount = temp;
2626 		xfs_iext_update_extent(ip, state, icur, &right);
2627 		break;
2628 
2629 	case 0:
2630 		/*
2631 		 * New allocation is not contiguous with another
2632 		 * delayed allocation.
2633 		 * Insert a new entry.
2634 		 */
2635 		oldlen = newlen = 0;
2636 		xfs_iext_insert(ip, icur, new, state);
2637 		break;
2638 	}
2639 	if (oldlen != newlen) {
2640 		ASSERT(oldlen > newlen);
2641 		xfs_mod_fdblocks(ip->i_mount, (int64_t)(oldlen - newlen),
2642 				 false);
2643 		/*
2644 		 * Nothing to do for disk quota accounting here.
2645 		 */
2646 	}
2647 }
2648 
2649 /*
2650  * Convert a hole to a real allocation.
2651  */
2652 STATIC int				/* error */
2653 xfs_bmap_add_extent_hole_real(
2654 	struct xfs_trans	*tp,
2655 	struct xfs_inode	*ip,
2656 	int			whichfork,
2657 	struct xfs_iext_cursor	*icur,
2658 	struct xfs_btree_cur	**curp,
2659 	struct xfs_bmbt_irec	*new,
2660 	xfs_fsblock_t		*first,
2661 	struct xfs_defer_ops	*dfops,
2662 	int			*logflagsp)
2663 {
2664 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
2665 	struct xfs_mount	*mp = ip->i_mount;
2666 	struct xfs_btree_cur	*cur = *curp;
2667 	int			error;	/* error return value */
2668 	int			i;	/* temp state */
2669 	xfs_bmbt_irec_t		left;	/* left neighbor extent entry */
2670 	xfs_bmbt_irec_t		right;	/* right neighbor extent entry */
2671 	int			rval=0;	/* return value (logging flags) */
2672 	int			state = xfs_bmap_fork_to_state(whichfork);
2673 	struct xfs_bmbt_irec	old;
2674 
2675 	ASSERT(!isnullstartblock(new->br_startblock));
2676 	ASSERT(!cur || !(cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
2677 
2678 	XFS_STATS_INC(mp, xs_add_exlist);
2679 
2680 	/*
2681 	 * Check and set flags if this segment has a left neighbor.
2682 	 */
2683 	if (xfs_iext_peek_prev_extent(ifp, icur, &left)) {
2684 		state |= BMAP_LEFT_VALID;
2685 		if (isnullstartblock(left.br_startblock))
2686 			state |= BMAP_LEFT_DELAY;
2687 	}
2688 
2689 	/*
2690 	 * Check and set flags if this segment has a current value.
2691 	 * Not true if we're inserting into the "hole" at eof.
2692 	 */
2693 	if (xfs_iext_get_extent(ifp, icur, &right)) {
2694 		state |= BMAP_RIGHT_VALID;
2695 		if (isnullstartblock(right.br_startblock))
2696 			state |= BMAP_RIGHT_DELAY;
2697 	}
2698 
2699 	/*
2700 	 * We're inserting a real allocation between "left" and "right".
2701 	 * Set the contiguity flags.  Don't let extents get too large.
2702 	 */
2703 	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
2704 	    left.br_startoff + left.br_blockcount == new->br_startoff &&
2705 	    left.br_startblock + left.br_blockcount == new->br_startblock &&
2706 	    left.br_state == new->br_state &&
2707 	    left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2708 		state |= BMAP_LEFT_CONTIG;
2709 
2710 	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
2711 	    new->br_startoff + new->br_blockcount == right.br_startoff &&
2712 	    new->br_startblock + new->br_blockcount == right.br_startblock &&
2713 	    new->br_state == right.br_state &&
2714 	    new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
2715 	    (!(state & BMAP_LEFT_CONTIG) ||
2716 	     left.br_blockcount + new->br_blockcount +
2717 	     right.br_blockcount <= MAXEXTLEN))
2718 		state |= BMAP_RIGHT_CONTIG;
2719 
2720 	error = 0;
2721 	/*
2722 	 * Select which case we're in here, and implement it.
2723 	 */
2724 	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
2725 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2726 		/*
2727 		 * New allocation is contiguous with real allocations on the
2728 		 * left and on the right.
2729 		 * Merge all three into a single extent record.
2730 		 */
2731 		left.br_blockcount += new->br_blockcount + right.br_blockcount;
2732 
2733 		xfs_iext_remove(ip, icur, state);
2734 		xfs_iext_prev(ifp, icur);
2735 		xfs_iext_update_extent(ip, state, icur, &left);
2736 
2737 		XFS_IFORK_NEXT_SET(ip, whichfork,
2738 			XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
2739 		if (cur == NULL) {
2740 			rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
2741 		} else {
2742 			rval = XFS_ILOG_CORE;
2743 			error = xfs_bmbt_lookup_eq(cur, &right, &i);
2744 			if (error)
2745 				goto done;
2746 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2747 			error = xfs_btree_delete(cur, &i);
2748 			if (error)
2749 				goto done;
2750 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2751 			error = xfs_btree_decrement(cur, 0, &i);
2752 			if (error)
2753 				goto done;
2754 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2755 			error = xfs_bmbt_update(cur, &left);
2756 			if (error)
2757 				goto done;
2758 		}
2759 		break;
2760 
2761 	case BMAP_LEFT_CONTIG:
2762 		/*
2763 		 * New allocation is contiguous with a real allocation
2764 		 * on the left.
2765 		 * Merge the new allocation with the left neighbor.
2766 		 */
2767 		old = left;
2768 		left.br_blockcount += new->br_blockcount;
2769 
2770 		xfs_iext_prev(ifp, icur);
2771 		xfs_iext_update_extent(ip, state, icur, &left);
2772 
2773 		if (cur == NULL) {
2774 			rval = xfs_ilog_fext(whichfork);
2775 		} else {
2776 			rval = 0;
2777 			error = xfs_bmbt_lookup_eq(cur, &old, &i);
2778 			if (error)
2779 				goto done;
2780 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2781 			error = xfs_bmbt_update(cur, &left);
2782 			if (error)
2783 				goto done;
2784 		}
2785 		break;
2786 
2787 	case BMAP_RIGHT_CONTIG:
2788 		/*
2789 		 * New allocation is contiguous with a real allocation
2790 		 * on the right.
2791 		 * Merge the new allocation with the right neighbor.
2792 		 */
2793 		old = right;
2794 
2795 		right.br_startoff = new->br_startoff;
2796 		right.br_startblock = new->br_startblock;
2797 		right.br_blockcount += new->br_blockcount;
2798 		xfs_iext_update_extent(ip, state, icur, &right);
2799 
2800 		if (cur == NULL) {
2801 			rval = xfs_ilog_fext(whichfork);
2802 		} else {
2803 			rval = 0;
2804 			error = xfs_bmbt_lookup_eq(cur, &old, &i);
2805 			if (error)
2806 				goto done;
2807 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2808 			error = xfs_bmbt_update(cur, &right);
2809 			if (error)
2810 				goto done;
2811 		}
2812 		break;
2813 
2814 	case 0:
2815 		/*
2816 		 * New allocation is not contiguous with another
2817 		 * real allocation.
2818 		 * Insert a new entry.
2819 		 */
2820 		xfs_iext_insert(ip, icur, new, state);
2821 		XFS_IFORK_NEXT_SET(ip, whichfork,
2822 			XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
2823 		if (cur == NULL) {
2824 			rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
2825 		} else {
2826 			rval = XFS_ILOG_CORE;
2827 			error = xfs_bmbt_lookup_eq(cur, new, &i);
2828 			if (error)
2829 				goto done;
2830 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2831 			error = xfs_btree_insert(cur, &i);
2832 			if (error)
2833 				goto done;
2834 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2835 		}
2836 		break;
2837 	}
2838 
2839 	/* add reverse mapping */
2840 	error = xfs_rmap_map_extent(mp, dfops, ip, whichfork, new);
2841 	if (error)
2842 		goto done;
2843 
2844 	/* convert to a btree if necessary */
2845 	if (xfs_bmap_needs_btree(ip, whichfork)) {
2846 		int	tmp_logflags;	/* partial log flag return val */
2847 
2848 		ASSERT(cur == NULL);
2849 		error = xfs_bmap_extents_to_btree(tp, ip, first, dfops, curp,
2850 				0, &tmp_logflags, whichfork);
2851 		*logflagsp |= tmp_logflags;
2852 		cur = *curp;
2853 		if (error)
2854 			goto done;
2855 	}
2856 
2857 	/* clear out the allocated field, done with it now in any case. */
2858 	if (cur)
2859 		cur->bc_private.b.allocated = 0;
2860 
2861 	xfs_bmap_check_leaf_extents(cur, ip, whichfork);
2862 done:
2863 	*logflagsp |= rval;
2864 	return error;
2865 }
2866 
2867 /*
2868  * Functions used in the extent read, allocate and remove paths
2869  */
2870 
2871 /*
2872  * Adjust the size of the new extent based on di_extsize and rt extsize.
2873  */
2874 int
2875 xfs_bmap_extsize_align(
2876 	xfs_mount_t	*mp,
2877 	xfs_bmbt_irec_t	*gotp,		/* next extent pointer */
2878 	xfs_bmbt_irec_t	*prevp,		/* previous extent pointer */
2879 	xfs_extlen_t	extsz,		/* align to this extent size */
2880 	int		rt,		/* is this a realtime inode? */
2881 	int		eof,		/* is extent at end-of-file? */
2882 	int		delay,		/* creating delalloc extent? */
2883 	int		convert,	/* overwriting unwritten extent? */
2884 	xfs_fileoff_t	*offp,		/* in/out: aligned offset */
2885 	xfs_extlen_t	*lenp)		/* in/out: aligned length */
2886 {
2887 	xfs_fileoff_t	orig_off;	/* original offset */
2888 	xfs_extlen_t	orig_alen;	/* original length */
2889 	xfs_fileoff_t	orig_end;	/* original off+len */
2890 	xfs_fileoff_t	nexto;		/* next file offset */
2891 	xfs_fileoff_t	prevo;		/* previous file offset */
2892 	xfs_fileoff_t	align_off;	/* temp for offset */
2893 	xfs_extlen_t	align_alen;	/* temp for length */
2894 	xfs_extlen_t	temp;		/* temp for calculations */
2895 
2896 	if (convert)
2897 		return 0;
2898 
2899 	orig_off = align_off = *offp;
2900 	orig_alen = align_alen = *lenp;
2901 	orig_end = orig_off + orig_alen;
2902 
2903 	/*
2904 	 * If this request overlaps an existing extent, then don't
2905 	 * attempt to perform any additional alignment.
2906 	 */
2907 	if (!delay && !eof &&
2908 	    (orig_off >= gotp->br_startoff) &&
2909 	    (orig_end <= gotp->br_startoff + gotp->br_blockcount)) {
2910 		return 0;
2911 	}
2912 
2913 	/*
2914 	 * If the file offset is unaligned vs. the extent size
2915 	 * we need to align it.  This will be possible unless
2916 	 * the file was previously written with a kernel that didn't
2917 	 * perform this alignment, or if a truncate shot us in the
2918 	 * foot.
2919 	 */
2920 	temp = do_mod(orig_off, extsz);
2921 	if (temp) {
2922 		align_alen += temp;
2923 		align_off -= temp;
2924 	}
2925 
2926 	/* Same adjustment for the end of the requested area. */
2927 	temp = (align_alen % extsz);
2928 	if (temp)
2929 		align_alen += extsz - temp;
2930 
2931 	/*
2932 	 * For large extent hint sizes, the aligned extent might be larger than
2933 	 * MAXEXTLEN. In that case, reduce the size by an extsz so that it pulls
2934 	 * the length back under MAXEXTLEN. The outer allocation loops handle
2935 	 * short allocation just fine, so it is safe to do this. We only want to
2936 	 * do it when we are forced to, though, because it means more allocation
2937 	 * operations are required.
2938 	 */
2939 	while (align_alen > MAXEXTLEN)
2940 		align_alen -= extsz;
2941 	ASSERT(align_alen <= MAXEXTLEN);
2942 
2943 	/*
2944 	 * If the previous block overlaps with this proposed allocation
2945 	 * then move the start forward without adjusting the length.
2946 	 */
2947 	if (prevp->br_startoff != NULLFILEOFF) {
2948 		if (prevp->br_startblock == HOLESTARTBLOCK)
2949 			prevo = prevp->br_startoff;
2950 		else
2951 			prevo = prevp->br_startoff + prevp->br_blockcount;
2952 	} else
2953 		prevo = 0;
2954 	if (align_off != orig_off && align_off < prevo)
2955 		align_off = prevo;
2956 	/*
2957 	 * If the next block overlaps with this proposed allocation
2958 	 * then move the start back without adjusting the length,
2959 	 * but not before offset 0.
2960 	 * This may of course make the start overlap previous block,
2961 	 * and if we hit the offset 0 limit then the next block
2962 	 * can still overlap too.
2963 	 */
2964 	if (!eof && gotp->br_startoff != NULLFILEOFF) {
2965 		if ((delay && gotp->br_startblock == HOLESTARTBLOCK) ||
2966 		    (!delay && gotp->br_startblock == DELAYSTARTBLOCK))
2967 			nexto = gotp->br_startoff + gotp->br_blockcount;
2968 		else
2969 			nexto = gotp->br_startoff;
2970 	} else
2971 		nexto = NULLFILEOFF;
2972 	if (!eof &&
2973 	    align_off + align_alen != orig_end &&
2974 	    align_off + align_alen > nexto)
2975 		align_off = nexto > align_alen ? nexto - align_alen : 0;
2976 	/*
2977 	 * If we're now overlapping the next or previous extent that
2978 	 * means we can't fit an extsz piece in this hole.  Just move
2979 	 * the start forward to the first valid spot and set
2980 	 * the length so we hit the end.
2981 	 */
2982 	if (align_off != orig_off && align_off < prevo)
2983 		align_off = prevo;
2984 	if (align_off + align_alen != orig_end &&
2985 	    align_off + align_alen > nexto &&
2986 	    nexto != NULLFILEOFF) {
2987 		ASSERT(nexto > prevo);
2988 		align_alen = nexto - align_off;
2989 	}
2990 
2991 	/*
2992 	 * If realtime, and the result isn't a multiple of the realtime
2993 	 * extent size we need to remove blocks until it is.
2994 	 */
2995 	if (rt && (temp = (align_alen % mp->m_sb.sb_rextsize))) {
2996 		/*
2997 		 * We're not covering the original request, or
2998 		 * we won't be able to once we fix the length.
2999 		 */
3000 		if (orig_off < align_off ||
3001 		    orig_end > align_off + align_alen ||
3002 		    align_alen - temp < orig_alen)
3003 			return -EINVAL;
3004 		/*
3005 		 * Try to fix it by moving the start up.
3006 		 */
3007 		if (align_off + temp <= orig_off) {
3008 			align_alen -= temp;
3009 			align_off += temp;
3010 		}
3011 		/*
3012 		 * Try to fix it by moving the end in.
3013 		 */
3014 		else if (align_off + align_alen - temp >= orig_end)
3015 			align_alen -= temp;
3016 		/*
3017 		 * Set the start to the minimum then trim the length.
3018 		 */
3019 		else {
3020 			align_alen -= orig_off - align_off;
3021 			align_off = orig_off;
3022 			align_alen -= align_alen % mp->m_sb.sb_rextsize;
3023 		}
3024 		/*
3025 		 * Result doesn't cover the request, fail it.
3026 		 */
3027 		if (orig_off < align_off || orig_end > align_off + align_alen)
3028 			return -EINVAL;
3029 	} else {
3030 		ASSERT(orig_off >= align_off);
3031 		/* see MAXEXTLEN handling above */
3032 		ASSERT(orig_end <= align_off + align_alen ||
3033 		       align_alen + extsz > MAXEXTLEN);
3034 	}
3035 
3036 #ifdef DEBUG
3037 	if (!eof && gotp->br_startoff != NULLFILEOFF)
3038 		ASSERT(align_off + align_alen <= gotp->br_startoff);
3039 	if (prevp->br_startoff != NULLFILEOFF)
3040 		ASSERT(align_off >= prevp->br_startoff + prevp->br_blockcount);
3041 #endif
3042 
3043 	*lenp = align_alen;
3044 	*offp = align_off;
3045 	return 0;
3046 }
3047 
3048 #define XFS_ALLOC_GAP_UNITS	4
3049 
3050 void
3051 xfs_bmap_adjacent(
3052 	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3053 {
3054 	xfs_fsblock_t	adjust;		/* adjustment to block numbers */
3055 	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */
3056 	xfs_mount_t	*mp;		/* mount point structure */
3057 	int		nullfb;		/* true if ap->firstblock isn't set */
3058 	int		rt;		/* true if inode is realtime */
3059 
3060 #define	ISVALID(x,y)	\
3061 	(rt ? \
3062 		(x) < mp->m_sb.sb_rblocks : \
3063 		XFS_FSB_TO_AGNO(mp, x) == XFS_FSB_TO_AGNO(mp, y) && \
3064 		XFS_FSB_TO_AGNO(mp, x) < mp->m_sb.sb_agcount && \
3065 		XFS_FSB_TO_AGBNO(mp, x) < mp->m_sb.sb_agblocks)
3066 
3067 	mp = ap->ip->i_mount;
3068 	nullfb = *ap->firstblock == NULLFSBLOCK;
3069 	rt = XFS_IS_REALTIME_INODE(ap->ip) &&
3070 		xfs_alloc_is_userdata(ap->datatype);
3071 	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, *ap->firstblock);
3072 	/*
3073 	 * If allocating at eof, and there's a previous real block,
3074 	 * try to use its last block as our starting point.
3075 	 */
3076 	if (ap->eof && ap->prev.br_startoff != NULLFILEOFF &&
3077 	    !isnullstartblock(ap->prev.br_startblock) &&
3078 	    ISVALID(ap->prev.br_startblock + ap->prev.br_blockcount,
3079 		    ap->prev.br_startblock)) {
3080 		ap->blkno = ap->prev.br_startblock + ap->prev.br_blockcount;
3081 		/*
3082 		 * Adjust for the gap between prevp and us.
3083 		 */
3084 		adjust = ap->offset -
3085 			(ap->prev.br_startoff + ap->prev.br_blockcount);
3086 		if (adjust &&
3087 		    ISVALID(ap->blkno + adjust, ap->prev.br_startblock))
3088 			ap->blkno += adjust;
3089 	}
3090 	/*
3091 	 * If not at eof, then compare the two neighbor blocks.
3092 	 * Figure out whether either one gives us a good starting point,
3093 	 * and pick the better one.
3094 	 */
3095 	else if (!ap->eof) {
3096 		xfs_fsblock_t	gotbno;		/* right side block number */
3097 		xfs_fsblock_t	gotdiff=0;	/* right side difference */
3098 		xfs_fsblock_t	prevbno;	/* left side block number */
3099 		xfs_fsblock_t	prevdiff=0;	/* left side difference */
3100 
3101 		/*
3102 		 * If there's a previous (left) block, select a requested
3103 		 * start block based on it.
3104 		 */
3105 		if (ap->prev.br_startoff != NULLFILEOFF &&
3106 		    !isnullstartblock(ap->prev.br_startblock) &&
3107 		    (prevbno = ap->prev.br_startblock +
3108 			       ap->prev.br_blockcount) &&
3109 		    ISVALID(prevbno, ap->prev.br_startblock)) {
3110 			/*
3111 			 * Calculate gap to end of previous block.
3112 			 */
3113 			adjust = prevdiff = ap->offset -
3114 				(ap->prev.br_startoff +
3115 				 ap->prev.br_blockcount);
3116 			/*
3117 			 * Figure the startblock based on the previous block's
3118 			 * end and the gap size.
3119 			 * Heuristic!
3120 			 * If the gap is large relative to the piece we're
3121 			 * allocating, or using it gives us an invalid block
3122 			 * number, then just use the end of the previous block.
3123 			 */
3124 			if (prevdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3125 			    ISVALID(prevbno + prevdiff,
3126 				    ap->prev.br_startblock))
3127 				prevbno += adjust;
3128 			else
3129 				prevdiff += adjust;
3130 			/*
3131 			 * If the firstblock forbids it, can't use it,
3132 			 * must use default.
3133 			 */
3134 			if (!rt && !nullfb &&
3135 			    XFS_FSB_TO_AGNO(mp, prevbno) != fb_agno)
3136 				prevbno = NULLFSBLOCK;
3137 		}
3138 		/*
3139 		 * No previous block or can't follow it, just default.
3140 		 */
3141 		else
3142 			prevbno = NULLFSBLOCK;
3143 		/*
3144 		 * If there's a following (right) block, select a requested
3145 		 * start block based on it.
3146 		 */
3147 		if (!isnullstartblock(ap->got.br_startblock)) {
3148 			/*
3149 			 * Calculate gap to start of next block.
3150 			 */
3151 			adjust = gotdiff = ap->got.br_startoff - ap->offset;
3152 			/*
3153 			 * Figure the startblock based on the next block's
3154 			 * start and the gap size.
3155 			 */
3156 			gotbno = ap->got.br_startblock;
3157 			/*
3158 			 * Heuristic!
3159 			 * If the gap is large relative to the piece we're
3160 			 * allocating, or using it gives us an invalid block
3161 			 * number, then just use the start of the next block
3162 			 * offset by our length.
3163 			 */
3164 			if (gotdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3165 			    ISVALID(gotbno - gotdiff, gotbno))
3166 				gotbno -= adjust;
3167 			else if (ISVALID(gotbno - ap->length, gotbno)) {
3168 				gotbno -= ap->length;
3169 				gotdiff += adjust - ap->length;
3170 			} else
3171 				gotdiff += adjust;
3172 			/*
3173 			 * If the firstblock forbids it, can't use it,
3174 			 * must use default.
3175 			 */
3176 			if (!rt && !nullfb &&
3177 			    XFS_FSB_TO_AGNO(mp, gotbno) != fb_agno)
3178 				gotbno = NULLFSBLOCK;
3179 		}
3180 		/*
3181 		 * No next block, just default.
3182 		 */
3183 		else
3184 			gotbno = NULLFSBLOCK;
3185 		/*
3186 		 * If both valid, pick the better one, else the only good
3187 		 * one, else ap->blkno is already set (to 0 or the inode block).
3188 		 */
3189 		if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK)
3190 			ap->blkno = prevdiff <= gotdiff ? prevbno : gotbno;
3191 		else if (prevbno != NULLFSBLOCK)
3192 			ap->blkno = prevbno;
3193 		else if (gotbno != NULLFSBLOCK)
3194 			ap->blkno = gotbno;
3195 	}
3196 #undef ISVALID
3197 }
3198 
3199 static int
3200 xfs_bmap_longest_free_extent(
3201 	struct xfs_trans	*tp,
3202 	xfs_agnumber_t		ag,
3203 	xfs_extlen_t		*blen,
3204 	int			*notinit)
3205 {
3206 	struct xfs_mount	*mp = tp->t_mountp;
3207 	struct xfs_perag	*pag;
3208 	xfs_extlen_t		longest;
3209 	int			error = 0;
3210 
3211 	pag = xfs_perag_get(mp, ag);
3212 	if (!pag->pagf_init) {
3213 		error = xfs_alloc_pagf_init(mp, tp, ag, XFS_ALLOC_FLAG_TRYLOCK);
3214 		if (error)
3215 			goto out;
3216 
3217 		if (!pag->pagf_init) {
3218 			*notinit = 1;
3219 			goto out;
3220 		}
3221 	}
3222 
3223 	longest = xfs_alloc_longest_free_extent(mp, pag,
3224 				xfs_alloc_min_freelist(mp, pag),
3225 				xfs_ag_resv_needed(pag, XFS_AG_RESV_NONE));
3226 	if (*blen < longest)
3227 		*blen = longest;
3228 
3229 out:
3230 	xfs_perag_put(pag);
3231 	return error;
3232 }
3233 
3234 static void
3235 xfs_bmap_select_minlen(
3236 	struct xfs_bmalloca	*ap,
3237 	struct xfs_alloc_arg	*args,
3238 	xfs_extlen_t		*blen,
3239 	int			notinit)
3240 {
3241 	if (notinit || *blen < ap->minlen) {
3242 		/*
3243 		 * Since we did a BUF_TRYLOCK above, it is possible that
3244 		 * there is space for this request.
3245 		 */
3246 		args->minlen = ap->minlen;
3247 	} else if (*blen < args->maxlen) {
3248 		/*
3249 		 * If the best seen length is less than the request length,
3250 		 * use the best as the minimum.
3251 		 */
3252 		args->minlen = *blen;
3253 	} else {
3254 		/*
3255 		 * Otherwise we've seen an extent as big as maxlen, use that
3256 		 * as the minimum.
3257 		 */
3258 		args->minlen = args->maxlen;
3259 	}
3260 }
3261 
3262 STATIC int
3263 xfs_bmap_btalloc_nullfb(
3264 	struct xfs_bmalloca	*ap,
3265 	struct xfs_alloc_arg	*args,
3266 	xfs_extlen_t		*blen)
3267 {
3268 	struct xfs_mount	*mp = ap->ip->i_mount;
3269 	xfs_agnumber_t		ag, startag;
3270 	int			notinit = 0;
3271 	int			error;
3272 
3273 	args->type = XFS_ALLOCTYPE_START_BNO;
3274 	args->total = ap->total;
3275 
3276 	startag = ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
3277 	if (startag == NULLAGNUMBER)
3278 		startag = ag = 0;
3279 
3280 	while (*blen < args->maxlen) {
3281 		error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
3282 						     &notinit);
3283 		if (error)
3284 			return error;
3285 
3286 		if (++ag == mp->m_sb.sb_agcount)
3287 			ag = 0;
3288 		if (ag == startag)
3289 			break;
3290 	}
3291 
3292 	xfs_bmap_select_minlen(ap, args, blen, notinit);
3293 	return 0;
3294 }
3295 
3296 STATIC int
3297 xfs_bmap_btalloc_filestreams(
3298 	struct xfs_bmalloca	*ap,
3299 	struct xfs_alloc_arg	*args,
3300 	xfs_extlen_t		*blen)
3301 {
3302 	struct xfs_mount	*mp = ap->ip->i_mount;
3303 	xfs_agnumber_t		ag;
3304 	int			notinit = 0;
3305 	int			error;
3306 
3307 	args->type = XFS_ALLOCTYPE_NEAR_BNO;
3308 	args->total = ap->total;
3309 
3310 	ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
3311 	if (ag == NULLAGNUMBER)
3312 		ag = 0;
3313 
3314 	error = xfs_bmap_longest_free_extent(args->tp, ag, blen, &notinit);
3315 	if (error)
3316 		return error;
3317 
3318 	if (*blen < args->maxlen) {
3319 		error = xfs_filestream_new_ag(ap, &ag);
3320 		if (error)
3321 			return error;
3322 
3323 		error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
3324 						     &notinit);
3325 		if (error)
3326 			return error;
3327 
3328 	}
3329 
3330 	xfs_bmap_select_minlen(ap, args, blen, notinit);
3331 
3332 	/*
3333 	 * Set the failure fallback case to look in the selected AG as stream
3334 	 * may have moved.
3335 	 */
3336 	ap->blkno = args->fsbno = XFS_AGB_TO_FSB(mp, ag, 0);
3337 	return 0;
3338 }
3339 
3340 /* Update all inode and quota accounting for the allocation we just did. */
3341 static void
3342 xfs_bmap_btalloc_accounting(
3343 	struct xfs_bmalloca	*ap,
3344 	struct xfs_alloc_arg	*args)
3345 {
3346 	if (ap->flags & XFS_BMAPI_COWFORK) {
3347 		/*
3348 		 * COW fork blocks are in-core only and thus are treated as
3349 		 * in-core quota reservation (like delalloc blocks) even when
3350 		 * converted to real blocks. The quota reservation is not
3351 		 * accounted to disk until blocks are remapped to the data
3352 		 * fork. So if these blocks were previously delalloc, we
3353 		 * already have quota reservation and there's nothing to do
3354 		 * yet.
3355 		 */
3356 		if (ap->wasdel)
3357 			return;
3358 
3359 		/*
3360 		 * Otherwise, we've allocated blocks in a hole. The transaction
3361 		 * has acquired in-core quota reservation for this extent.
3362 		 * Rather than account these as real blocks, however, we reduce
3363 		 * the transaction quota reservation based on the allocation.
3364 		 * This essentially transfers the transaction quota reservation
3365 		 * to that of a delalloc extent.
3366 		 */
3367 		ap->ip->i_delayed_blks += args->len;
3368 		xfs_trans_mod_dquot_byino(ap->tp, ap->ip, XFS_TRANS_DQ_RES_BLKS,
3369 				-(long)args->len);
3370 		return;
3371 	}
3372 
3373 	/* data/attr fork only */
3374 	ap->ip->i_d.di_nblocks += args->len;
3375 	xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
3376 	if (ap->wasdel)
3377 		ap->ip->i_delayed_blks -= args->len;
3378 	xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
3379 		ap->wasdel ? XFS_TRANS_DQ_DELBCOUNT : XFS_TRANS_DQ_BCOUNT,
3380 		args->len);
3381 }
3382 
3383 STATIC int
3384 xfs_bmap_btalloc(
3385 	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3386 {
3387 	xfs_mount_t	*mp;		/* mount point structure */
3388 	xfs_alloctype_t	atype = 0;	/* type for allocation routines */
3389 	xfs_extlen_t	align = 0;	/* minimum allocation alignment */
3390 	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */
3391 	xfs_agnumber_t	ag;
3392 	xfs_alloc_arg_t	args;
3393 	xfs_fileoff_t	orig_offset;
3394 	xfs_extlen_t	orig_length;
3395 	xfs_extlen_t	blen;
3396 	xfs_extlen_t	nextminlen = 0;
3397 	int		nullfb;		/* true if ap->firstblock isn't set */
3398 	int		isaligned;
3399 	int		tryagain;
3400 	int		error;
3401 	int		stripe_align;
3402 
3403 	ASSERT(ap->length);
3404 	orig_offset = ap->offset;
3405 	orig_length = ap->length;
3406 
3407 	mp = ap->ip->i_mount;
3408 
3409 	/* stripe alignment for allocation is determined by mount parameters */
3410 	stripe_align = 0;
3411 	if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC))
3412 		stripe_align = mp->m_swidth;
3413 	else if (mp->m_dalign)
3414 		stripe_align = mp->m_dalign;
3415 
3416 	if (ap->flags & XFS_BMAPI_COWFORK)
3417 		align = xfs_get_cowextsz_hint(ap->ip);
3418 	else if (xfs_alloc_is_userdata(ap->datatype))
3419 		align = xfs_get_extsz_hint(ap->ip);
3420 	if (align) {
3421 		error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
3422 						align, 0, ap->eof, 0, ap->conv,
3423 						&ap->offset, &ap->length);
3424 		ASSERT(!error);
3425 		ASSERT(ap->length);
3426 	}
3427 
3428 
3429 	nullfb = *ap->firstblock == NULLFSBLOCK;
3430 	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, *ap->firstblock);
3431 	if (nullfb) {
3432 		if (xfs_alloc_is_userdata(ap->datatype) &&
3433 		    xfs_inode_is_filestream(ap->ip)) {
3434 			ag = xfs_filestream_lookup_ag(ap->ip);
3435 			ag = (ag != NULLAGNUMBER) ? ag : 0;
3436 			ap->blkno = XFS_AGB_TO_FSB(mp, ag, 0);
3437 		} else {
3438 			ap->blkno = XFS_INO_TO_FSB(mp, ap->ip->i_ino);
3439 		}
3440 	} else
3441 		ap->blkno = *ap->firstblock;
3442 
3443 	xfs_bmap_adjacent(ap);
3444 
3445 	/*
3446 	 * If allowed, use ap->blkno; otherwise must use firstblock since
3447 	 * it's in the right allocation group.
3448 	 */
3449 	if (nullfb || XFS_FSB_TO_AGNO(mp, ap->blkno) == fb_agno)
3450 		;
3451 	else
3452 		ap->blkno = *ap->firstblock;
3453 	/*
3454 	 * Normal allocation, done through xfs_alloc_vextent.
3455 	 */
3456 	tryagain = isaligned = 0;
3457 	memset(&args, 0, sizeof(args));
3458 	args.tp = ap->tp;
3459 	args.mp = mp;
3460 	args.fsbno = ap->blkno;
3461 	xfs_rmap_skip_owner_update(&args.oinfo);
3462 
3463 	/* Trim the allocation back to the maximum an AG can fit. */
3464 	args.maxlen = MIN(ap->length, mp->m_ag_max_usable);
3465 	args.firstblock = *ap->firstblock;
3466 	blen = 0;
3467 	if (nullfb) {
3468 		/*
3469 		 * Search for an allocation group with a single extent large
3470 		 * enough for the request.  If one isn't found, then adjust
3471 		 * the minimum allocation size to the largest space found.
3472 		 */
3473 		if (xfs_alloc_is_userdata(ap->datatype) &&
3474 		    xfs_inode_is_filestream(ap->ip))
3475 			error = xfs_bmap_btalloc_filestreams(ap, &args, &blen);
3476 		else
3477 			error = xfs_bmap_btalloc_nullfb(ap, &args, &blen);
3478 		if (error)
3479 			return error;
3480 	} else if (ap->dfops->dop_low) {
3481 		if (xfs_inode_is_filestream(ap->ip))
3482 			args.type = XFS_ALLOCTYPE_FIRST_AG;
3483 		else
3484 			args.type = XFS_ALLOCTYPE_START_BNO;
3485 		args.total = args.minlen = ap->minlen;
3486 	} else {
3487 		args.type = XFS_ALLOCTYPE_NEAR_BNO;
3488 		args.total = ap->total;
3489 		args.minlen = ap->minlen;
3490 	}
3491 	/* apply extent size hints if obtained earlier */
3492 	if (align) {
3493 		args.prod = align;
3494 		if ((args.mod = (xfs_extlen_t)do_mod(ap->offset, args.prod)))
3495 			args.mod = (xfs_extlen_t)(args.prod - args.mod);
3496 	} else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
3497 		args.prod = 1;
3498 		args.mod = 0;
3499 	} else {
3500 		args.prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
3501 		if ((args.mod = (xfs_extlen_t)(do_mod(ap->offset, args.prod))))
3502 			args.mod = (xfs_extlen_t)(args.prod - args.mod);
3503 	}
3504 	/*
3505 	 * If we are not low on available data blocks, and the
3506 	 * underlying logical volume manager is a stripe, and
3507 	 * the file offset is zero then try to allocate data
3508 	 * blocks on stripe unit boundary.
3509 	 * NOTE: ap->aeof is only set if the allocation length
3510 	 * is >= the stripe unit and the allocation offset is
3511 	 * at the end of file.
3512 	 */
3513 	if (!ap->dfops->dop_low && ap->aeof) {
3514 		if (!ap->offset) {
3515 			args.alignment = stripe_align;
3516 			atype = args.type;
3517 			isaligned = 1;
3518 			/*
3519 			 * Adjust for alignment
3520 			 */
3521 			if (blen > args.alignment && blen <= args.maxlen)
3522 				args.minlen = blen - args.alignment;
3523 			args.minalignslop = 0;
3524 		} else {
3525 			/*
3526 			 * First try an exact bno allocation.
3527 			 * If it fails then do a near or start bno
3528 			 * allocation with alignment turned on.
3529 			 */
3530 			atype = args.type;
3531 			tryagain = 1;
3532 			args.type = XFS_ALLOCTYPE_THIS_BNO;
3533 			args.alignment = 1;
3534 			/*
3535 			 * Compute the minlen+alignment for the
3536 			 * next case.  Set slop so that the value
3537 			 * of minlen+alignment+slop doesn't go up
3538 			 * between the calls.
3539 			 */
3540 			if (blen > stripe_align && blen <= args.maxlen)
3541 				nextminlen = blen - stripe_align;
3542 			else
3543 				nextminlen = args.minlen;
3544 			if (nextminlen + stripe_align > args.minlen + 1)
3545 				args.minalignslop =
3546 					nextminlen + stripe_align -
3547 					args.minlen - 1;
3548 			else
3549 				args.minalignslop = 0;
3550 		}
3551 	} else {
3552 		args.alignment = 1;
3553 		args.minalignslop = 0;
3554 	}
3555 	args.minleft = ap->minleft;
3556 	args.wasdel = ap->wasdel;
3557 	args.resv = XFS_AG_RESV_NONE;
3558 	args.datatype = ap->datatype;
3559 	if (ap->datatype & XFS_ALLOC_USERDATA_ZERO)
3560 		args.ip = ap->ip;
3561 
3562 	error = xfs_alloc_vextent(&args);
3563 	if (error)
3564 		return error;
3565 
3566 	if (tryagain && args.fsbno == NULLFSBLOCK) {
3567 		/*
3568 		 * Exact allocation failed. Now try with alignment
3569 		 * turned on.
3570 		 */
3571 		args.type = atype;
3572 		args.fsbno = ap->blkno;
3573 		args.alignment = stripe_align;
3574 		args.minlen = nextminlen;
3575 		args.minalignslop = 0;
3576 		isaligned = 1;
3577 		if ((error = xfs_alloc_vextent(&args)))
3578 			return error;
3579 	}
3580 	if (isaligned && args.fsbno == NULLFSBLOCK) {
3581 		/*
3582 		 * allocation failed, so turn off alignment and
3583 		 * try again.
3584 		 */
3585 		args.type = atype;
3586 		args.fsbno = ap->blkno;
3587 		args.alignment = 0;
3588 		if ((error = xfs_alloc_vextent(&args)))
3589 			return error;
3590 	}
3591 	if (args.fsbno == NULLFSBLOCK && nullfb &&
3592 	    args.minlen > ap->minlen) {
3593 		args.minlen = ap->minlen;
3594 		args.type = XFS_ALLOCTYPE_START_BNO;
3595 		args.fsbno = ap->blkno;
3596 		if ((error = xfs_alloc_vextent(&args)))
3597 			return error;
3598 	}
3599 	if (args.fsbno == NULLFSBLOCK && nullfb) {
3600 		args.fsbno = 0;
3601 		args.type = XFS_ALLOCTYPE_FIRST_AG;
3602 		args.total = ap->minlen;
3603 		if ((error = xfs_alloc_vextent(&args)))
3604 			return error;
3605 		ap->dfops->dop_low = true;
3606 	}
3607 	if (args.fsbno != NULLFSBLOCK) {
3608 		/*
3609 		 * check the allocation happened at the same or higher AG than
3610 		 * the first block that was allocated.
3611 		 */
3612 		ASSERT(*ap->firstblock == NULLFSBLOCK ||
3613 		       XFS_FSB_TO_AGNO(mp, *ap->firstblock) <=
3614 		       XFS_FSB_TO_AGNO(mp, args.fsbno));
3615 
3616 		ap->blkno = args.fsbno;
3617 		if (*ap->firstblock == NULLFSBLOCK)
3618 			*ap->firstblock = args.fsbno;
3619 		ASSERT(nullfb || fb_agno <= args.agno);
3620 		ap->length = args.len;
3621 		/*
3622 		 * If the extent size hint is active, we tried to round the
3623 		 * caller's allocation request offset down to extsz and the
3624 		 * length up to another extsz boundary.  If we found a free
3625 		 * extent we mapped it in starting at this new offset.  If the
3626 		 * newly mapped space isn't long enough to cover any of the
3627 		 * range of offsets that was originally requested, move the
3628 		 * mapping up so that we can fill as much of the caller's
3629 		 * original request as possible.  Free space is apparently
3630 		 * very fragmented so we're unlikely to be able to satisfy the
3631 		 * hints anyway.
3632 		 */
3633 		if (ap->length <= orig_length)
3634 			ap->offset = orig_offset;
3635 		else if (ap->offset + ap->length < orig_offset + orig_length)
3636 			ap->offset = orig_offset + orig_length - ap->length;
3637 		xfs_bmap_btalloc_accounting(ap, &args);
3638 	} else {
3639 		ap->blkno = NULLFSBLOCK;
3640 		ap->length = 0;
3641 	}
3642 	return 0;
3643 }
3644 
3645 /*
3646  * xfs_bmap_alloc is called by xfs_bmapi to allocate an extent for a file.
3647  * It figures out where to ask the underlying allocator to put the new extent.
3648  */
3649 STATIC int
3650 xfs_bmap_alloc(
3651 	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3652 {
3653 	if (XFS_IS_REALTIME_INODE(ap->ip) &&
3654 	    xfs_alloc_is_userdata(ap->datatype))
3655 		return xfs_bmap_rtalloc(ap);
3656 	return xfs_bmap_btalloc(ap);
3657 }
3658 
3659 /* Trim extent to fit a logical block range. */
3660 void
3661 xfs_trim_extent(
3662 	struct xfs_bmbt_irec	*irec,
3663 	xfs_fileoff_t		bno,
3664 	xfs_filblks_t		len)
3665 {
3666 	xfs_fileoff_t		distance;
3667 	xfs_fileoff_t		end = bno + len;
3668 
3669 	if (irec->br_startoff + irec->br_blockcount <= bno ||
3670 	    irec->br_startoff >= end) {
3671 		irec->br_blockcount = 0;
3672 		return;
3673 	}
3674 
3675 	if (irec->br_startoff < bno) {
3676 		distance = bno - irec->br_startoff;
3677 		if (isnullstartblock(irec->br_startblock))
3678 			irec->br_startblock = DELAYSTARTBLOCK;
3679 		if (irec->br_startblock != DELAYSTARTBLOCK &&
3680 		    irec->br_startblock != HOLESTARTBLOCK)
3681 			irec->br_startblock += distance;
3682 		irec->br_startoff += distance;
3683 		irec->br_blockcount -= distance;
3684 	}
3685 
3686 	if (end < irec->br_startoff + irec->br_blockcount) {
3687 		distance = irec->br_startoff + irec->br_blockcount - end;
3688 		irec->br_blockcount -= distance;
3689 	}
3690 }
3691 
3692 /* trim extent to within eof */
3693 void
3694 xfs_trim_extent_eof(
3695 	struct xfs_bmbt_irec	*irec,
3696 	struct xfs_inode	*ip)
3697 
3698 {
3699 	xfs_trim_extent(irec, 0, XFS_B_TO_FSB(ip->i_mount,
3700 					      i_size_read(VFS_I(ip))));
3701 }
3702 
3703 /*
3704  * Trim the returned map to the required bounds
3705  */
3706 STATIC void
3707 xfs_bmapi_trim_map(
3708 	struct xfs_bmbt_irec	*mval,
3709 	struct xfs_bmbt_irec	*got,
3710 	xfs_fileoff_t		*bno,
3711 	xfs_filblks_t		len,
3712 	xfs_fileoff_t		obno,
3713 	xfs_fileoff_t		end,
3714 	int			n,
3715 	int			flags)
3716 {
3717 	if ((flags & XFS_BMAPI_ENTIRE) ||
3718 	    got->br_startoff + got->br_blockcount <= obno) {
3719 		*mval = *got;
3720 		if (isnullstartblock(got->br_startblock))
3721 			mval->br_startblock = DELAYSTARTBLOCK;
3722 		return;
3723 	}
3724 
3725 	if (obno > *bno)
3726 		*bno = obno;
3727 	ASSERT((*bno >= obno) || (n == 0));
3728 	ASSERT(*bno < end);
3729 	mval->br_startoff = *bno;
3730 	if (isnullstartblock(got->br_startblock))
3731 		mval->br_startblock = DELAYSTARTBLOCK;
3732 	else
3733 		mval->br_startblock = got->br_startblock +
3734 					(*bno - got->br_startoff);
3735 	/*
3736 	 * Return the minimum of what we got and what we asked for for
3737 	 * the length.  We can use the len variable here because it is
3738 	 * modified below and we could have been there before coming
3739 	 * here if the first part of the allocation didn't overlap what
3740 	 * was asked for.
3741 	 */
3742 	mval->br_blockcount = XFS_FILBLKS_MIN(end - *bno,
3743 			got->br_blockcount - (*bno - got->br_startoff));
3744 	mval->br_state = got->br_state;
3745 	ASSERT(mval->br_blockcount <= len);
3746 	return;
3747 }
3748 
3749 /*
3750  * Update and validate the extent map to return
3751  */
3752 STATIC void
3753 xfs_bmapi_update_map(
3754 	struct xfs_bmbt_irec	**map,
3755 	xfs_fileoff_t		*bno,
3756 	xfs_filblks_t		*len,
3757 	xfs_fileoff_t		obno,
3758 	xfs_fileoff_t		end,
3759 	int			*n,
3760 	int			flags)
3761 {
3762 	xfs_bmbt_irec_t	*mval = *map;
3763 
3764 	ASSERT((flags & XFS_BMAPI_ENTIRE) ||
3765 	       ((mval->br_startoff + mval->br_blockcount) <= end));
3766 	ASSERT((flags & XFS_BMAPI_ENTIRE) || (mval->br_blockcount <= *len) ||
3767 	       (mval->br_startoff < obno));
3768 
3769 	*bno = mval->br_startoff + mval->br_blockcount;
3770 	*len = end - *bno;
3771 	if (*n > 0 && mval->br_startoff == mval[-1].br_startoff) {
3772 		/* update previous map with new information */
3773 		ASSERT(mval->br_startblock == mval[-1].br_startblock);
3774 		ASSERT(mval->br_blockcount > mval[-1].br_blockcount);
3775 		ASSERT(mval->br_state == mval[-1].br_state);
3776 		mval[-1].br_blockcount = mval->br_blockcount;
3777 		mval[-1].br_state = mval->br_state;
3778 	} else if (*n > 0 && mval->br_startblock != DELAYSTARTBLOCK &&
3779 		   mval[-1].br_startblock != DELAYSTARTBLOCK &&
3780 		   mval[-1].br_startblock != HOLESTARTBLOCK &&
3781 		   mval->br_startblock == mval[-1].br_startblock +
3782 					  mval[-1].br_blockcount &&
3783 		   ((flags & XFS_BMAPI_IGSTATE) ||
3784 			mval[-1].br_state == mval->br_state)) {
3785 		ASSERT(mval->br_startoff ==
3786 		       mval[-1].br_startoff + mval[-1].br_blockcount);
3787 		mval[-1].br_blockcount += mval->br_blockcount;
3788 	} else if (*n > 0 &&
3789 		   mval->br_startblock == DELAYSTARTBLOCK &&
3790 		   mval[-1].br_startblock == DELAYSTARTBLOCK &&
3791 		   mval->br_startoff ==
3792 		   mval[-1].br_startoff + mval[-1].br_blockcount) {
3793 		mval[-1].br_blockcount += mval->br_blockcount;
3794 		mval[-1].br_state = mval->br_state;
3795 	} else if (!((*n == 0) &&
3796 		     ((mval->br_startoff + mval->br_blockcount) <=
3797 		      obno))) {
3798 		mval++;
3799 		(*n)++;
3800 	}
3801 	*map = mval;
3802 }
3803 
3804 /*
3805  * Map file blocks to filesystem blocks without allocation.
3806  */
3807 int
3808 xfs_bmapi_read(
3809 	struct xfs_inode	*ip,
3810 	xfs_fileoff_t		bno,
3811 	xfs_filblks_t		len,
3812 	struct xfs_bmbt_irec	*mval,
3813 	int			*nmap,
3814 	int			flags)
3815 {
3816 	struct xfs_mount	*mp = ip->i_mount;
3817 	struct xfs_ifork	*ifp;
3818 	struct xfs_bmbt_irec	got;
3819 	xfs_fileoff_t		obno;
3820 	xfs_fileoff_t		end;
3821 	struct xfs_iext_cursor	icur;
3822 	int			error;
3823 	bool			eof = false;
3824 	int			n = 0;
3825 	int			whichfork = xfs_bmapi_whichfork(flags);
3826 
3827 	ASSERT(*nmap >= 1);
3828 	ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK|XFS_BMAPI_ENTIRE|
3829 			   XFS_BMAPI_IGSTATE|XFS_BMAPI_COWFORK)));
3830 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED|XFS_ILOCK_EXCL));
3831 
3832 	if (unlikely(XFS_TEST_ERROR(
3833 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
3834 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
3835 	     mp, XFS_ERRTAG_BMAPIFORMAT))) {
3836 		XFS_ERROR_REPORT("xfs_bmapi_read", XFS_ERRLEVEL_LOW, mp);
3837 		return -EFSCORRUPTED;
3838 	}
3839 
3840 	if (XFS_FORCED_SHUTDOWN(mp))
3841 		return -EIO;
3842 
3843 	XFS_STATS_INC(mp, xs_blk_mapr);
3844 
3845 	ifp = XFS_IFORK_PTR(ip, whichfork);
3846 
3847 	/* No CoW fork?  Return a hole. */
3848 	if (whichfork == XFS_COW_FORK && !ifp) {
3849 		mval->br_startoff = bno;
3850 		mval->br_startblock = HOLESTARTBLOCK;
3851 		mval->br_blockcount = len;
3852 		mval->br_state = XFS_EXT_NORM;
3853 		*nmap = 1;
3854 		return 0;
3855 	}
3856 
3857 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
3858 		error = xfs_iread_extents(NULL, ip, whichfork);
3859 		if (error)
3860 			return error;
3861 	}
3862 
3863 	if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got))
3864 		eof = true;
3865 	end = bno + len;
3866 	obno = bno;
3867 
3868 	while (bno < end && n < *nmap) {
3869 		/* Reading past eof, act as though there's a hole up to end. */
3870 		if (eof)
3871 			got.br_startoff = end;
3872 		if (got.br_startoff > bno) {
3873 			/* Reading in a hole.  */
3874 			mval->br_startoff = bno;
3875 			mval->br_startblock = HOLESTARTBLOCK;
3876 			mval->br_blockcount =
3877 				XFS_FILBLKS_MIN(len, got.br_startoff - bno);
3878 			mval->br_state = XFS_EXT_NORM;
3879 			bno += mval->br_blockcount;
3880 			len -= mval->br_blockcount;
3881 			mval++;
3882 			n++;
3883 			continue;
3884 		}
3885 
3886 		/* set up the extent map to return. */
3887 		xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags);
3888 		xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
3889 
3890 		/* If we're done, stop now. */
3891 		if (bno >= end || n >= *nmap)
3892 			break;
3893 
3894 		/* Else go on to the next record. */
3895 		if (!xfs_iext_next_extent(ifp, &icur, &got))
3896 			eof = true;
3897 	}
3898 	*nmap = n;
3899 	return 0;
3900 }
3901 
3902 /*
3903  * Add a delayed allocation extent to an inode. Blocks are reserved from the
3904  * global pool and the extent inserted into the inode in-core extent tree.
3905  *
3906  * On entry, got refers to the first extent beyond the offset of the extent to
3907  * allocate or eof is specified if no such extent exists. On return, got refers
3908  * to the extent record that was inserted to the inode fork.
3909  *
3910  * Note that the allocated extent may have been merged with contiguous extents
3911  * during insertion into the inode fork. Thus, got does not reflect the current
3912  * state of the inode fork on return. If necessary, the caller can use lastx to
3913  * look up the updated record in the inode fork.
3914  */
3915 int
3916 xfs_bmapi_reserve_delalloc(
3917 	struct xfs_inode	*ip,
3918 	int			whichfork,
3919 	xfs_fileoff_t		off,
3920 	xfs_filblks_t		len,
3921 	xfs_filblks_t		prealloc,
3922 	struct xfs_bmbt_irec	*got,
3923 	struct xfs_iext_cursor	*icur,
3924 	int			eof)
3925 {
3926 	struct xfs_mount	*mp = ip->i_mount;
3927 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
3928 	xfs_extlen_t		alen;
3929 	xfs_extlen_t		indlen;
3930 	int			error;
3931 	xfs_fileoff_t		aoff = off;
3932 
3933 	/*
3934 	 * Cap the alloc length. Keep track of prealloc so we know whether to
3935 	 * tag the inode before we return.
3936 	 */
3937 	alen = XFS_FILBLKS_MIN(len + prealloc, MAXEXTLEN);
3938 	if (!eof)
3939 		alen = XFS_FILBLKS_MIN(alen, got->br_startoff - aoff);
3940 	if (prealloc && alen >= len)
3941 		prealloc = alen - len;
3942 
3943 	/* Figure out the extent size, adjust alen */
3944 	if (whichfork == XFS_COW_FORK) {
3945 		struct xfs_bmbt_irec	prev;
3946 		xfs_extlen_t		extsz = xfs_get_cowextsz_hint(ip);
3947 
3948 		if (!xfs_iext_peek_prev_extent(ifp, icur, &prev))
3949 			prev.br_startoff = NULLFILEOFF;
3950 
3951 		error = xfs_bmap_extsize_align(mp, got, &prev, extsz, 0, eof,
3952 					       1, 0, &aoff, &alen);
3953 		ASSERT(!error);
3954 	}
3955 
3956 	/*
3957 	 * Make a transaction-less quota reservation for delayed allocation
3958 	 * blocks.  This number gets adjusted later.  We return if we haven't
3959 	 * allocated blocks already inside this loop.
3960 	 */
3961 	error = xfs_trans_reserve_quota_nblks(NULL, ip, (long)alen, 0,
3962 						XFS_QMOPT_RES_REGBLKS);
3963 	if (error)
3964 		return error;
3965 
3966 	/*
3967 	 * Split changing sb for alen and indlen since they could be coming
3968 	 * from different places.
3969 	 */
3970 	indlen = (xfs_extlen_t)xfs_bmap_worst_indlen(ip, alen);
3971 	ASSERT(indlen > 0);
3972 
3973 	error = xfs_mod_fdblocks(mp, -((int64_t)alen), false);
3974 	if (error)
3975 		goto out_unreserve_quota;
3976 
3977 	error = xfs_mod_fdblocks(mp, -((int64_t)indlen), false);
3978 	if (error)
3979 		goto out_unreserve_blocks;
3980 
3981 
3982 	ip->i_delayed_blks += alen;
3983 
3984 	got->br_startoff = aoff;
3985 	got->br_startblock = nullstartblock(indlen);
3986 	got->br_blockcount = alen;
3987 	got->br_state = XFS_EXT_NORM;
3988 
3989 	xfs_bmap_add_extent_hole_delay(ip, whichfork, icur, got);
3990 
3991 	/*
3992 	 * Tag the inode if blocks were preallocated. Note that COW fork
3993 	 * preallocation can occur at the start or end of the extent, even when
3994 	 * prealloc == 0, so we must also check the aligned offset and length.
3995 	 */
3996 	if (whichfork == XFS_DATA_FORK && prealloc)
3997 		xfs_inode_set_eofblocks_tag(ip);
3998 	if (whichfork == XFS_COW_FORK && (prealloc || aoff < off || alen > len))
3999 		xfs_inode_set_cowblocks_tag(ip);
4000 
4001 	return 0;
4002 
4003 out_unreserve_blocks:
4004 	xfs_mod_fdblocks(mp, alen, false);
4005 out_unreserve_quota:
4006 	if (XFS_IS_QUOTA_ON(mp))
4007 		xfs_trans_unreserve_quota_nblks(NULL, ip, (long)alen, 0,
4008 						XFS_QMOPT_RES_REGBLKS);
4009 	return error;
4010 }
4011 
4012 static int
4013 xfs_bmapi_allocate(
4014 	struct xfs_bmalloca	*bma)
4015 {
4016 	struct xfs_mount	*mp = bma->ip->i_mount;
4017 	int			whichfork = xfs_bmapi_whichfork(bma->flags);
4018 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(bma->ip, whichfork);
4019 	int			tmp_logflags = 0;
4020 	int			error;
4021 
4022 	ASSERT(bma->length > 0);
4023 
4024 	/*
4025 	 * For the wasdelay case, we could also just allocate the stuff asked
4026 	 * for in this bmap call but that wouldn't be as good.
4027 	 */
4028 	if (bma->wasdel) {
4029 		bma->length = (xfs_extlen_t)bma->got.br_blockcount;
4030 		bma->offset = bma->got.br_startoff;
4031 		xfs_iext_peek_prev_extent(ifp, &bma->icur, &bma->prev);
4032 	} else {
4033 		bma->length = XFS_FILBLKS_MIN(bma->length, MAXEXTLEN);
4034 		if (!bma->eof)
4035 			bma->length = XFS_FILBLKS_MIN(bma->length,
4036 					bma->got.br_startoff - bma->offset);
4037 	}
4038 
4039 	/*
4040 	 * Set the data type being allocated. For the data fork, the first data
4041 	 * in the file is treated differently to all other allocations. For the
4042 	 * attribute fork, we only need to ensure the allocated range is not on
4043 	 * the busy list.
4044 	 */
4045 	if (!(bma->flags & XFS_BMAPI_METADATA)) {
4046 		bma->datatype = XFS_ALLOC_NOBUSY;
4047 		if (whichfork == XFS_DATA_FORK) {
4048 			if (bma->offset == 0)
4049 				bma->datatype |= XFS_ALLOC_INITIAL_USER_DATA;
4050 			else
4051 				bma->datatype |= XFS_ALLOC_USERDATA;
4052 		}
4053 		if (bma->flags & XFS_BMAPI_ZERO)
4054 			bma->datatype |= XFS_ALLOC_USERDATA_ZERO;
4055 	}
4056 
4057 	bma->minlen = (bma->flags & XFS_BMAPI_CONTIG) ? bma->length : 1;
4058 
4059 	/*
4060 	 * Only want to do the alignment at the eof if it is userdata and
4061 	 * allocation length is larger than a stripe unit.
4062 	 */
4063 	if (mp->m_dalign && bma->length >= mp->m_dalign &&
4064 	    !(bma->flags & XFS_BMAPI_METADATA) && whichfork == XFS_DATA_FORK) {
4065 		error = xfs_bmap_isaeof(bma, whichfork);
4066 		if (error)
4067 			return error;
4068 	}
4069 
4070 	error = xfs_bmap_alloc(bma);
4071 	if (error)
4072 		return error;
4073 
4074 	if (bma->cur)
4075 		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4076 	if (bma->blkno == NULLFSBLOCK)
4077 		return 0;
4078 	if ((ifp->if_flags & XFS_IFBROOT) && !bma->cur) {
4079 		bma->cur = xfs_bmbt_init_cursor(mp, bma->tp, bma->ip, whichfork);
4080 		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4081 		bma->cur->bc_private.b.dfops = bma->dfops;
4082 	}
4083 	/*
4084 	 * Bump the number of extents we've allocated
4085 	 * in this call.
4086 	 */
4087 	bma->nallocs++;
4088 
4089 	if (bma->cur)
4090 		bma->cur->bc_private.b.flags =
4091 			bma->wasdel ? XFS_BTCUR_BPRV_WASDEL : 0;
4092 
4093 	bma->got.br_startoff = bma->offset;
4094 	bma->got.br_startblock = bma->blkno;
4095 	bma->got.br_blockcount = bma->length;
4096 	bma->got.br_state = XFS_EXT_NORM;
4097 
4098 	/*
4099 	 * In the data fork, a wasdelay extent has been initialized, so
4100 	 * shouldn't be flagged as unwritten.
4101 	 *
4102 	 * For the cow fork, however, we convert delalloc reservations
4103 	 * (extents allocated for speculative preallocation) to
4104 	 * allocated unwritten extents, and only convert the unwritten
4105 	 * extents to real extents when we're about to write the data.
4106 	 */
4107 	if ((!bma->wasdel || (bma->flags & XFS_BMAPI_COWFORK)) &&
4108 	    (bma->flags & XFS_BMAPI_PREALLOC) &&
4109 	    xfs_sb_version_hasextflgbit(&mp->m_sb))
4110 		bma->got.br_state = XFS_EXT_UNWRITTEN;
4111 
4112 	if (bma->wasdel)
4113 		error = xfs_bmap_add_extent_delay_real(bma, whichfork);
4114 	else
4115 		error = xfs_bmap_add_extent_hole_real(bma->tp, bma->ip,
4116 				whichfork, &bma->icur, &bma->cur, &bma->got,
4117 				bma->firstblock, bma->dfops, &bma->logflags);
4118 
4119 	bma->logflags |= tmp_logflags;
4120 	if (error)
4121 		return error;
4122 
4123 	/*
4124 	 * Update our extent pointer, given that xfs_bmap_add_extent_delay_real
4125 	 * or xfs_bmap_add_extent_hole_real might have merged it into one of
4126 	 * the neighbouring ones.
4127 	 */
4128 	xfs_iext_get_extent(ifp, &bma->icur, &bma->got);
4129 
4130 	ASSERT(bma->got.br_startoff <= bma->offset);
4131 	ASSERT(bma->got.br_startoff + bma->got.br_blockcount >=
4132 	       bma->offset + bma->length);
4133 	ASSERT(bma->got.br_state == XFS_EXT_NORM ||
4134 	       bma->got.br_state == XFS_EXT_UNWRITTEN);
4135 	return 0;
4136 }
4137 
4138 STATIC int
4139 xfs_bmapi_convert_unwritten(
4140 	struct xfs_bmalloca	*bma,
4141 	struct xfs_bmbt_irec	*mval,
4142 	xfs_filblks_t		len,
4143 	int			flags)
4144 {
4145 	int			whichfork = xfs_bmapi_whichfork(flags);
4146 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(bma->ip, whichfork);
4147 	int			tmp_logflags = 0;
4148 	int			error;
4149 
4150 	/* check if we need to do unwritten->real conversion */
4151 	if (mval->br_state == XFS_EXT_UNWRITTEN &&
4152 	    (flags & XFS_BMAPI_PREALLOC))
4153 		return 0;
4154 
4155 	/* check if we need to do real->unwritten conversion */
4156 	if (mval->br_state == XFS_EXT_NORM &&
4157 	    (flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT)) !=
4158 			(XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT))
4159 		return 0;
4160 
4161 	/*
4162 	 * Modify (by adding) the state flag, if writing.
4163 	 */
4164 	ASSERT(mval->br_blockcount <= len);
4165 	if ((ifp->if_flags & XFS_IFBROOT) && !bma->cur) {
4166 		bma->cur = xfs_bmbt_init_cursor(bma->ip->i_mount, bma->tp,
4167 					bma->ip, whichfork);
4168 		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4169 		bma->cur->bc_private.b.dfops = bma->dfops;
4170 	}
4171 	mval->br_state = (mval->br_state == XFS_EXT_UNWRITTEN)
4172 				? XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
4173 
4174 	/*
4175 	 * Before insertion into the bmbt, zero the range being converted
4176 	 * if required.
4177 	 */
4178 	if (flags & XFS_BMAPI_ZERO) {
4179 		error = xfs_zero_extent(bma->ip, mval->br_startblock,
4180 					mval->br_blockcount);
4181 		if (error)
4182 			return error;
4183 	}
4184 
4185 	error = xfs_bmap_add_extent_unwritten_real(bma->tp, bma->ip, whichfork,
4186 			&bma->icur, &bma->cur, mval, bma->firstblock,
4187 			bma->dfops, &tmp_logflags);
4188 	/*
4189 	 * Log the inode core unconditionally in the unwritten extent conversion
4190 	 * path because the conversion might not have done so (e.g., if the
4191 	 * extent count hasn't changed). We need to make sure the inode is dirty
4192 	 * in the transaction for the sake of fsync(), even if nothing has
4193 	 * changed, because fsync() will not force the log for this transaction
4194 	 * unless it sees the inode pinned.
4195 	 *
4196 	 * Note: If we're only converting cow fork extents, there aren't
4197 	 * any on-disk updates to make, so we don't need to log anything.
4198 	 */
4199 	if (whichfork != XFS_COW_FORK)
4200 		bma->logflags |= tmp_logflags | XFS_ILOG_CORE;
4201 	if (error)
4202 		return error;
4203 
4204 	/*
4205 	 * Update our extent pointer, given that
4206 	 * xfs_bmap_add_extent_unwritten_real might have merged it into one
4207 	 * of the neighbouring ones.
4208 	 */
4209 	xfs_iext_get_extent(ifp, &bma->icur, &bma->got);
4210 
4211 	/*
4212 	 * We may have combined previously unwritten space with written space,
4213 	 * so generate another request.
4214 	 */
4215 	if (mval->br_blockcount < len)
4216 		return -EAGAIN;
4217 	return 0;
4218 }
4219 
4220 /*
4221  * Map file blocks to filesystem blocks, and allocate blocks or convert the
4222  * extent state if necessary.  Details behaviour is controlled by the flags
4223  * parameter.  Only allocates blocks from a single allocation group, to avoid
4224  * locking problems.
4225  *
4226  * The returned value in "firstblock" from the first call in a transaction
4227  * must be remembered and presented to subsequent calls in "firstblock".
4228  * An upper bound for the number of blocks to be allocated is supplied to
4229  * the first call in "total"; if no allocation group has that many free
4230  * blocks then the call will fail (return NULLFSBLOCK in "firstblock").
4231  */
4232 int
4233 xfs_bmapi_write(
4234 	struct xfs_trans	*tp,		/* transaction pointer */
4235 	struct xfs_inode	*ip,		/* incore inode */
4236 	xfs_fileoff_t		bno,		/* starting file offs. mapped */
4237 	xfs_filblks_t		len,		/* length to map in file */
4238 	int			flags,		/* XFS_BMAPI_... */
4239 	xfs_fsblock_t		*firstblock,	/* first allocated block
4240 						   controls a.g. for allocs */
4241 	xfs_extlen_t		total,		/* total blocks needed */
4242 	struct xfs_bmbt_irec	*mval,		/* output: map values */
4243 	int			*nmap,		/* i/o: mval size/count */
4244 	struct xfs_defer_ops	*dfops)		/* i/o: list extents to free */
4245 {
4246 	struct xfs_mount	*mp = ip->i_mount;
4247 	struct xfs_ifork	*ifp;
4248 	struct xfs_bmalloca	bma = { NULL };	/* args for xfs_bmap_alloc */
4249 	xfs_fileoff_t		end;		/* end of mapped file region */
4250 	bool			eof = false;	/* after the end of extents */
4251 	int			error;		/* error return */
4252 	int			n;		/* current extent index */
4253 	xfs_fileoff_t		obno;		/* old block number (offset) */
4254 	int			whichfork;	/* data or attr fork */
4255 
4256 #ifdef DEBUG
4257 	xfs_fileoff_t		orig_bno;	/* original block number value */
4258 	int			orig_flags;	/* original flags arg value */
4259 	xfs_filblks_t		orig_len;	/* original value of len arg */
4260 	struct xfs_bmbt_irec	*orig_mval;	/* original value of mval */
4261 	int			orig_nmap;	/* original value of *nmap */
4262 
4263 	orig_bno = bno;
4264 	orig_len = len;
4265 	orig_flags = flags;
4266 	orig_mval = mval;
4267 	orig_nmap = *nmap;
4268 #endif
4269 	whichfork = xfs_bmapi_whichfork(flags);
4270 
4271 	ASSERT(*nmap >= 1);
4272 	ASSERT(*nmap <= XFS_BMAP_MAX_NMAP);
4273 	ASSERT(!(flags & XFS_BMAPI_IGSTATE));
4274 	ASSERT(tp != NULL ||
4275 	       (flags & (XFS_BMAPI_CONVERT | XFS_BMAPI_COWFORK)) ==
4276 			(XFS_BMAPI_CONVERT | XFS_BMAPI_COWFORK));
4277 	ASSERT(len > 0);
4278 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL);
4279 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4280 	ASSERT(!(flags & XFS_BMAPI_REMAP));
4281 
4282 	/* zeroing is for currently only for data extents, not metadata */
4283 	ASSERT((flags & (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO)) !=
4284 			(XFS_BMAPI_METADATA | XFS_BMAPI_ZERO));
4285 	/*
4286 	 * we can allocate unwritten extents or pre-zero allocated blocks,
4287 	 * but it makes no sense to do both at once. This would result in
4288 	 * zeroing the unwritten extent twice, but it still being an
4289 	 * unwritten extent....
4290 	 */
4291 	ASSERT((flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO)) !=
4292 			(XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO));
4293 
4294 	if (unlikely(XFS_TEST_ERROR(
4295 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
4296 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
4297 	     mp, XFS_ERRTAG_BMAPIFORMAT))) {
4298 		XFS_ERROR_REPORT("xfs_bmapi_write", XFS_ERRLEVEL_LOW, mp);
4299 		return -EFSCORRUPTED;
4300 	}
4301 
4302 	if (XFS_FORCED_SHUTDOWN(mp))
4303 		return -EIO;
4304 
4305 	ifp = XFS_IFORK_PTR(ip, whichfork);
4306 
4307 	XFS_STATS_INC(mp, xs_blk_mapw);
4308 
4309 	if (*firstblock == NULLFSBLOCK) {
4310 		if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE)
4311 			bma.minleft = be16_to_cpu(ifp->if_broot->bb_level) + 1;
4312 		else
4313 			bma.minleft = 1;
4314 	} else {
4315 		bma.minleft = 0;
4316 	}
4317 
4318 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
4319 		error = xfs_iread_extents(tp, ip, whichfork);
4320 		if (error)
4321 			goto error0;
4322 	}
4323 
4324 	n = 0;
4325 	end = bno + len;
4326 	obno = bno;
4327 
4328 	if (!xfs_iext_lookup_extent(ip, ifp, bno, &bma.icur, &bma.got))
4329 		eof = true;
4330 	if (!xfs_iext_peek_prev_extent(ifp, &bma.icur, &bma.prev))
4331 		bma.prev.br_startoff = NULLFILEOFF;
4332 	bma.tp = tp;
4333 	bma.ip = ip;
4334 	bma.total = total;
4335 	bma.datatype = 0;
4336 	bma.dfops = dfops;
4337 	bma.firstblock = firstblock;
4338 
4339 	while (bno < end && n < *nmap) {
4340 		bool			need_alloc = false, wasdelay = false;
4341 
4342 		/* in hole or beyond EOF? */
4343 		if (eof || bma.got.br_startoff > bno) {
4344 			/*
4345 			 * CoW fork conversions should /never/ hit EOF or
4346 			 * holes.  There should always be something for us
4347 			 * to work on.
4348 			 */
4349 			ASSERT(!((flags & XFS_BMAPI_CONVERT) &&
4350 			         (flags & XFS_BMAPI_COWFORK)));
4351 
4352 			if (flags & XFS_BMAPI_DELALLOC) {
4353 				/*
4354 				 * For the COW fork we can reasonably get a
4355 				 * request for converting an extent that races
4356 				 * with other threads already having converted
4357 				 * part of it, as there converting COW to
4358 				 * regular blocks is not protected using the
4359 				 * IOLOCK.
4360 				 */
4361 				ASSERT(flags & XFS_BMAPI_COWFORK);
4362 				if (!(flags & XFS_BMAPI_COWFORK)) {
4363 					error = -EIO;
4364 					goto error0;
4365 				}
4366 
4367 				if (eof || bno >= end)
4368 					break;
4369 			} else {
4370 				need_alloc = true;
4371 			}
4372 		} else if (isnullstartblock(bma.got.br_startblock)) {
4373 			wasdelay = true;
4374 		}
4375 
4376 		/*
4377 		 * First, deal with the hole before the allocated space
4378 		 * that we found, if any.
4379 		 */
4380 		if ((need_alloc || wasdelay) &&
4381 		    !(flags & XFS_BMAPI_CONVERT_ONLY)) {
4382 			bma.eof = eof;
4383 			bma.conv = !!(flags & XFS_BMAPI_CONVERT);
4384 			bma.wasdel = wasdelay;
4385 			bma.offset = bno;
4386 			bma.flags = flags;
4387 
4388 			/*
4389 			 * There's a 32/64 bit type mismatch between the
4390 			 * allocation length request (which can be 64 bits in
4391 			 * length) and the bma length request, which is
4392 			 * xfs_extlen_t and therefore 32 bits. Hence we have to
4393 			 * check for 32-bit overflows and handle them here.
4394 			 */
4395 			if (len > (xfs_filblks_t)MAXEXTLEN)
4396 				bma.length = MAXEXTLEN;
4397 			else
4398 				bma.length = len;
4399 
4400 			ASSERT(len > 0);
4401 			ASSERT(bma.length > 0);
4402 			error = xfs_bmapi_allocate(&bma);
4403 			if (error)
4404 				goto error0;
4405 			if (bma.blkno == NULLFSBLOCK)
4406 				break;
4407 
4408 			/*
4409 			 * If this is a CoW allocation, record the data in
4410 			 * the refcount btree for orphan recovery.
4411 			 */
4412 			if (whichfork == XFS_COW_FORK) {
4413 				error = xfs_refcount_alloc_cow_extent(mp, dfops,
4414 						bma.blkno, bma.length);
4415 				if (error)
4416 					goto error0;
4417 			}
4418 		}
4419 
4420 		/* Deal with the allocated space we found.  */
4421 		xfs_bmapi_trim_map(mval, &bma.got, &bno, len, obno,
4422 							end, n, flags);
4423 
4424 		/* Execute unwritten extent conversion if necessary */
4425 		error = xfs_bmapi_convert_unwritten(&bma, mval, len, flags);
4426 		if (error == -EAGAIN)
4427 			continue;
4428 		if (error)
4429 			goto error0;
4430 
4431 		/* update the extent map to return */
4432 		xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
4433 
4434 		/*
4435 		 * If we're done, stop now.  Stop when we've allocated
4436 		 * XFS_BMAP_MAX_NMAP extents no matter what.  Otherwise
4437 		 * the transaction may get too big.
4438 		 */
4439 		if (bno >= end || n >= *nmap || bma.nallocs >= *nmap)
4440 			break;
4441 
4442 		/* Else go on to the next record. */
4443 		bma.prev = bma.got;
4444 		if (!xfs_iext_next_extent(ifp, &bma.icur, &bma.got))
4445 			eof = true;
4446 	}
4447 	*nmap = n;
4448 
4449 	/*
4450 	 * Transform from btree to extents, give it cur.
4451 	 */
4452 	if (xfs_bmap_wants_extents(ip, whichfork)) {
4453 		int		tmp_logflags = 0;
4454 
4455 		ASSERT(bma.cur);
4456 		error = xfs_bmap_btree_to_extents(tp, ip, bma.cur,
4457 			&tmp_logflags, whichfork);
4458 		bma.logflags |= tmp_logflags;
4459 		if (error)
4460 			goto error0;
4461 	}
4462 
4463 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE ||
4464 	       XFS_IFORK_NEXTENTS(ip, whichfork) >
4465 		XFS_IFORK_MAXEXT(ip, whichfork));
4466 	error = 0;
4467 error0:
4468 	/*
4469 	 * Log everything.  Do this after conversion, there's no point in
4470 	 * logging the extent records if we've converted to btree format.
4471 	 */
4472 	if ((bma.logflags & xfs_ilog_fext(whichfork)) &&
4473 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
4474 		bma.logflags &= ~xfs_ilog_fext(whichfork);
4475 	else if ((bma.logflags & xfs_ilog_fbroot(whichfork)) &&
4476 		 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
4477 		bma.logflags &= ~xfs_ilog_fbroot(whichfork);
4478 	/*
4479 	 * Log whatever the flags say, even if error.  Otherwise we might miss
4480 	 * detecting a case where the data is changed, there's an error,
4481 	 * and it's not logged so we don't shutdown when we should.
4482 	 */
4483 	if (bma.logflags)
4484 		xfs_trans_log_inode(tp, ip, bma.logflags);
4485 
4486 	if (bma.cur) {
4487 		if (!error) {
4488 			ASSERT(*firstblock == NULLFSBLOCK ||
4489 			       XFS_FSB_TO_AGNO(mp, *firstblock) <=
4490 			       XFS_FSB_TO_AGNO(mp,
4491 				       bma.cur->bc_private.b.firstblock));
4492 			*firstblock = bma.cur->bc_private.b.firstblock;
4493 		}
4494 		xfs_btree_del_cursor(bma.cur,
4495 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
4496 	}
4497 	if (!error)
4498 		xfs_bmap_validate_ret(orig_bno, orig_len, orig_flags, orig_mval,
4499 			orig_nmap, *nmap);
4500 	return error;
4501 }
4502 
4503 static int
4504 xfs_bmapi_remap(
4505 	struct xfs_trans	*tp,
4506 	struct xfs_inode	*ip,
4507 	xfs_fileoff_t		bno,
4508 	xfs_filblks_t		len,
4509 	xfs_fsblock_t		startblock,
4510 	struct xfs_defer_ops	*dfops)
4511 {
4512 	struct xfs_mount	*mp = ip->i_mount;
4513 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
4514 	struct xfs_btree_cur	*cur = NULL;
4515 	xfs_fsblock_t		firstblock = NULLFSBLOCK;
4516 	struct xfs_bmbt_irec	got;
4517 	struct xfs_iext_cursor	icur;
4518 	int			logflags = 0, error;
4519 
4520 	ASSERT(len > 0);
4521 	ASSERT(len <= (xfs_filblks_t)MAXEXTLEN);
4522 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4523 
4524 	if (unlikely(XFS_TEST_ERROR(
4525 	    (XFS_IFORK_FORMAT(ip, XFS_DATA_FORK) != XFS_DINODE_FMT_EXTENTS &&
4526 	     XFS_IFORK_FORMAT(ip, XFS_DATA_FORK) != XFS_DINODE_FMT_BTREE),
4527 	     mp, XFS_ERRTAG_BMAPIFORMAT))) {
4528 		XFS_ERROR_REPORT("xfs_bmapi_remap", XFS_ERRLEVEL_LOW, mp);
4529 		return -EFSCORRUPTED;
4530 	}
4531 
4532 	if (XFS_FORCED_SHUTDOWN(mp))
4533 		return -EIO;
4534 
4535 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
4536 		error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK);
4537 		if (error)
4538 			return error;
4539 	}
4540 
4541 	if (xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) {
4542 		/* make sure we only reflink into a hole. */
4543 		ASSERT(got.br_startoff > bno);
4544 		ASSERT(got.br_startoff - bno >= len);
4545 	}
4546 
4547 	ip->i_d.di_nblocks += len;
4548 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
4549 
4550 	if (ifp->if_flags & XFS_IFBROOT) {
4551 		cur = xfs_bmbt_init_cursor(mp, tp, ip, XFS_DATA_FORK);
4552 		cur->bc_private.b.firstblock = firstblock;
4553 		cur->bc_private.b.dfops = dfops;
4554 		cur->bc_private.b.flags = 0;
4555 	}
4556 
4557 	got.br_startoff = bno;
4558 	got.br_startblock = startblock;
4559 	got.br_blockcount = len;
4560 	got.br_state = XFS_EXT_NORM;
4561 
4562 	error = xfs_bmap_add_extent_hole_real(tp, ip, XFS_DATA_FORK, &icur,
4563 			&cur, &got, &firstblock, dfops, &logflags);
4564 	if (error)
4565 		goto error0;
4566 
4567 	if (xfs_bmap_wants_extents(ip, XFS_DATA_FORK)) {
4568 		int		tmp_logflags = 0;
4569 
4570 		error = xfs_bmap_btree_to_extents(tp, ip, cur,
4571 			&tmp_logflags, XFS_DATA_FORK);
4572 		logflags |= tmp_logflags;
4573 	}
4574 
4575 error0:
4576 	if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS)
4577 		logflags &= ~XFS_ILOG_DEXT;
4578 	else if (ip->i_d.di_format != XFS_DINODE_FMT_BTREE)
4579 		logflags &= ~XFS_ILOG_DBROOT;
4580 
4581 	if (logflags)
4582 		xfs_trans_log_inode(tp, ip, logflags);
4583 	if (cur) {
4584 		xfs_btree_del_cursor(cur,
4585 				error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
4586 	}
4587 	return error;
4588 }
4589 
4590 /*
4591  * When a delalloc extent is split (e.g., due to a hole punch), the original
4592  * indlen reservation must be shared across the two new extents that are left
4593  * behind.
4594  *
4595  * Given the original reservation and the worst case indlen for the two new
4596  * extents (as calculated by xfs_bmap_worst_indlen()), split the original
4597  * reservation fairly across the two new extents. If necessary, steal available
4598  * blocks from a deleted extent to make up a reservation deficiency (e.g., if
4599  * ores == 1). The number of stolen blocks is returned. The availability and
4600  * subsequent accounting of stolen blocks is the responsibility of the caller.
4601  */
4602 static xfs_filblks_t
4603 xfs_bmap_split_indlen(
4604 	xfs_filblks_t			ores,		/* original res. */
4605 	xfs_filblks_t			*indlen1,	/* ext1 worst indlen */
4606 	xfs_filblks_t			*indlen2,	/* ext2 worst indlen */
4607 	xfs_filblks_t			avail)		/* stealable blocks */
4608 {
4609 	xfs_filblks_t			len1 = *indlen1;
4610 	xfs_filblks_t			len2 = *indlen2;
4611 	xfs_filblks_t			nres = len1 + len2; /* new total res. */
4612 	xfs_filblks_t			stolen = 0;
4613 	xfs_filblks_t			resfactor;
4614 
4615 	/*
4616 	 * Steal as many blocks as we can to try and satisfy the worst case
4617 	 * indlen for both new extents.
4618 	 */
4619 	if (ores < nres && avail)
4620 		stolen = XFS_FILBLKS_MIN(nres - ores, avail);
4621 	ores += stolen;
4622 
4623 	 /* nothing else to do if we've satisfied the new reservation */
4624 	if (ores >= nres)
4625 		return stolen;
4626 
4627 	/*
4628 	 * We can't meet the total required reservation for the two extents.
4629 	 * Calculate the percent of the overall shortage between both extents
4630 	 * and apply this percentage to each of the requested indlen values.
4631 	 * This distributes the shortage fairly and reduces the chances that one
4632 	 * of the two extents is left with nothing when extents are repeatedly
4633 	 * split.
4634 	 */
4635 	resfactor = (ores * 100);
4636 	do_div(resfactor, nres);
4637 	len1 *= resfactor;
4638 	do_div(len1, 100);
4639 	len2 *= resfactor;
4640 	do_div(len2, 100);
4641 	ASSERT(len1 + len2 <= ores);
4642 	ASSERT(len1 < *indlen1 && len2 < *indlen2);
4643 
4644 	/*
4645 	 * Hand out the remainder to each extent. If one of the two reservations
4646 	 * is zero, we want to make sure that one gets a block first. The loop
4647 	 * below starts with len1, so hand len2 a block right off the bat if it
4648 	 * is zero.
4649 	 */
4650 	ores -= (len1 + len2);
4651 	ASSERT((*indlen1 - len1) + (*indlen2 - len2) >= ores);
4652 	if (ores && !len2 && *indlen2) {
4653 		len2++;
4654 		ores--;
4655 	}
4656 	while (ores) {
4657 		if (len1 < *indlen1) {
4658 			len1++;
4659 			ores--;
4660 		}
4661 		if (!ores)
4662 			break;
4663 		if (len2 < *indlen2) {
4664 			len2++;
4665 			ores--;
4666 		}
4667 	}
4668 
4669 	*indlen1 = len1;
4670 	*indlen2 = len2;
4671 
4672 	return stolen;
4673 }
4674 
4675 int
4676 xfs_bmap_del_extent_delay(
4677 	struct xfs_inode	*ip,
4678 	int			whichfork,
4679 	struct xfs_iext_cursor	*icur,
4680 	struct xfs_bmbt_irec	*got,
4681 	struct xfs_bmbt_irec	*del)
4682 {
4683 	struct xfs_mount	*mp = ip->i_mount;
4684 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
4685 	struct xfs_bmbt_irec	new;
4686 	int64_t			da_old, da_new, da_diff = 0;
4687 	xfs_fileoff_t		del_endoff, got_endoff;
4688 	xfs_filblks_t		got_indlen, new_indlen, stolen;
4689 	int			state = xfs_bmap_fork_to_state(whichfork);
4690 	int			error = 0;
4691 	bool			isrt;
4692 
4693 	XFS_STATS_INC(mp, xs_del_exlist);
4694 
4695 	isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
4696 	del_endoff = del->br_startoff + del->br_blockcount;
4697 	got_endoff = got->br_startoff + got->br_blockcount;
4698 	da_old = startblockval(got->br_startblock);
4699 	da_new = 0;
4700 
4701 	ASSERT(del->br_blockcount > 0);
4702 	ASSERT(got->br_startoff <= del->br_startoff);
4703 	ASSERT(got_endoff >= del_endoff);
4704 
4705 	if (isrt) {
4706 		uint64_t rtexts = XFS_FSB_TO_B(mp, del->br_blockcount);
4707 
4708 		do_div(rtexts, mp->m_sb.sb_rextsize);
4709 		xfs_mod_frextents(mp, rtexts);
4710 	}
4711 
4712 	/*
4713 	 * Update the inode delalloc counter now and wait to update the
4714 	 * sb counters as we might have to borrow some blocks for the
4715 	 * indirect block accounting.
4716 	 */
4717 	error = xfs_trans_reserve_quota_nblks(NULL, ip,
4718 			-((long)del->br_blockcount), 0,
4719 			isrt ? XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS);
4720 	if (error)
4721 		return error;
4722 	ip->i_delayed_blks -= del->br_blockcount;
4723 
4724 	if (got->br_startoff == del->br_startoff)
4725 		state |= BMAP_LEFT_FILLING;
4726 	if (got_endoff == del_endoff)
4727 		state |= BMAP_RIGHT_FILLING;
4728 
4729 	switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
4730 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
4731 		/*
4732 		 * Matches the whole extent.  Delete the entry.
4733 		 */
4734 		xfs_iext_remove(ip, icur, state);
4735 		xfs_iext_prev(ifp, icur);
4736 		break;
4737 	case BMAP_LEFT_FILLING:
4738 		/*
4739 		 * Deleting the first part of the extent.
4740 		 */
4741 		got->br_startoff = del_endoff;
4742 		got->br_blockcount -= del->br_blockcount;
4743 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4744 				got->br_blockcount), da_old);
4745 		got->br_startblock = nullstartblock((int)da_new);
4746 		xfs_iext_update_extent(ip, state, icur, got);
4747 		break;
4748 	case BMAP_RIGHT_FILLING:
4749 		/*
4750 		 * Deleting the last part of the extent.
4751 		 */
4752 		got->br_blockcount = got->br_blockcount - del->br_blockcount;
4753 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4754 				got->br_blockcount), da_old);
4755 		got->br_startblock = nullstartblock((int)da_new);
4756 		xfs_iext_update_extent(ip, state, icur, got);
4757 		break;
4758 	case 0:
4759 		/*
4760 		 * Deleting the middle of the extent.
4761 		 *
4762 		 * Distribute the original indlen reservation across the two new
4763 		 * extents.  Steal blocks from the deleted extent if necessary.
4764 		 * Stealing blocks simply fudges the fdblocks accounting below.
4765 		 * Warn if either of the new indlen reservations is zero as this
4766 		 * can lead to delalloc problems.
4767 		 */
4768 		got->br_blockcount = del->br_startoff - got->br_startoff;
4769 		got_indlen = xfs_bmap_worst_indlen(ip, got->br_blockcount);
4770 
4771 		new.br_blockcount = got_endoff - del_endoff;
4772 		new_indlen = xfs_bmap_worst_indlen(ip, new.br_blockcount);
4773 
4774 		WARN_ON_ONCE(!got_indlen || !new_indlen);
4775 		stolen = xfs_bmap_split_indlen(da_old, &got_indlen, &new_indlen,
4776 						       del->br_blockcount);
4777 
4778 		got->br_startblock = nullstartblock((int)got_indlen);
4779 
4780 		new.br_startoff = del_endoff;
4781 		new.br_state = got->br_state;
4782 		new.br_startblock = nullstartblock((int)new_indlen);
4783 
4784 		xfs_iext_update_extent(ip, state, icur, got);
4785 		xfs_iext_next(ifp, icur);
4786 		xfs_iext_insert(ip, icur, &new, state);
4787 
4788 		da_new = got_indlen + new_indlen - stolen;
4789 		del->br_blockcount -= stolen;
4790 		break;
4791 	}
4792 
4793 	ASSERT(da_old >= da_new);
4794 	da_diff = da_old - da_new;
4795 	if (!isrt)
4796 		da_diff += del->br_blockcount;
4797 	if (da_diff)
4798 		xfs_mod_fdblocks(mp, da_diff, false);
4799 	return error;
4800 }
4801 
4802 void
4803 xfs_bmap_del_extent_cow(
4804 	struct xfs_inode	*ip,
4805 	struct xfs_iext_cursor	*icur,
4806 	struct xfs_bmbt_irec	*got,
4807 	struct xfs_bmbt_irec	*del)
4808 {
4809 	struct xfs_mount	*mp = ip->i_mount;
4810 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
4811 	struct xfs_bmbt_irec	new;
4812 	xfs_fileoff_t		del_endoff, got_endoff;
4813 	int			state = BMAP_COWFORK;
4814 
4815 	XFS_STATS_INC(mp, xs_del_exlist);
4816 
4817 	del_endoff = del->br_startoff + del->br_blockcount;
4818 	got_endoff = got->br_startoff + got->br_blockcount;
4819 
4820 	ASSERT(del->br_blockcount > 0);
4821 	ASSERT(got->br_startoff <= del->br_startoff);
4822 	ASSERT(got_endoff >= del_endoff);
4823 	ASSERT(!isnullstartblock(got->br_startblock));
4824 
4825 	if (got->br_startoff == del->br_startoff)
4826 		state |= BMAP_LEFT_FILLING;
4827 	if (got_endoff == del_endoff)
4828 		state |= BMAP_RIGHT_FILLING;
4829 
4830 	switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
4831 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
4832 		/*
4833 		 * Matches the whole extent.  Delete the entry.
4834 		 */
4835 		xfs_iext_remove(ip, icur, state);
4836 		xfs_iext_prev(ifp, icur);
4837 		break;
4838 	case BMAP_LEFT_FILLING:
4839 		/*
4840 		 * Deleting the first part of the extent.
4841 		 */
4842 		got->br_startoff = del_endoff;
4843 		got->br_blockcount -= del->br_blockcount;
4844 		got->br_startblock = del->br_startblock + del->br_blockcount;
4845 		xfs_iext_update_extent(ip, state, icur, got);
4846 		break;
4847 	case BMAP_RIGHT_FILLING:
4848 		/*
4849 		 * Deleting the last part of the extent.
4850 		 */
4851 		got->br_blockcount -= del->br_blockcount;
4852 		xfs_iext_update_extent(ip, state, icur, got);
4853 		break;
4854 	case 0:
4855 		/*
4856 		 * Deleting the middle of the extent.
4857 		 */
4858 		got->br_blockcount = del->br_startoff - got->br_startoff;
4859 
4860 		new.br_startoff = del_endoff;
4861 		new.br_blockcount = got_endoff - del_endoff;
4862 		new.br_state = got->br_state;
4863 		new.br_startblock = del->br_startblock + del->br_blockcount;
4864 
4865 		xfs_iext_update_extent(ip, state, icur, got);
4866 		xfs_iext_next(ifp, icur);
4867 		xfs_iext_insert(ip, icur, &new, state);
4868 		break;
4869 	}
4870 	ip->i_delayed_blks -= del->br_blockcount;
4871 }
4872 
4873 /*
4874  * Called by xfs_bmapi to update file extent records and the btree
4875  * after removing space.
4876  */
4877 STATIC int				/* error */
4878 xfs_bmap_del_extent_real(
4879 	xfs_inode_t		*ip,	/* incore inode pointer */
4880 	xfs_trans_t		*tp,	/* current transaction pointer */
4881 	struct xfs_iext_cursor	*icur,
4882 	struct xfs_defer_ops	*dfops,	/* list of extents to be freed */
4883 	xfs_btree_cur_t		*cur,	/* if null, not a btree */
4884 	xfs_bmbt_irec_t		*del,	/* data to remove from extents */
4885 	int			*logflagsp, /* inode logging flags */
4886 	int			whichfork, /* data or attr fork */
4887 	int			bflags)	/* bmapi flags */
4888 {
4889 	xfs_fsblock_t		del_endblock=0;	/* first block past del */
4890 	xfs_fileoff_t		del_endoff;	/* first offset past del */
4891 	int			do_fx;	/* free extent at end of routine */
4892 	int			error;	/* error return value */
4893 	int			flags = 0;/* inode logging flags */
4894 	struct xfs_bmbt_irec	got;	/* current extent entry */
4895 	xfs_fileoff_t		got_endoff;	/* first offset past got */
4896 	int			i;	/* temp state */
4897 	xfs_ifork_t		*ifp;	/* inode fork pointer */
4898 	xfs_mount_t		*mp;	/* mount structure */
4899 	xfs_filblks_t		nblks;	/* quota/sb block count */
4900 	xfs_bmbt_irec_t		new;	/* new record to be inserted */
4901 	/* REFERENCED */
4902 	uint			qfield;	/* quota field to update */
4903 	int			state = xfs_bmap_fork_to_state(whichfork);
4904 	struct xfs_bmbt_irec	old;
4905 
4906 	mp = ip->i_mount;
4907 	XFS_STATS_INC(mp, xs_del_exlist);
4908 
4909 	ifp = XFS_IFORK_PTR(ip, whichfork);
4910 	ASSERT(del->br_blockcount > 0);
4911 	xfs_iext_get_extent(ifp, icur, &got);
4912 	ASSERT(got.br_startoff <= del->br_startoff);
4913 	del_endoff = del->br_startoff + del->br_blockcount;
4914 	got_endoff = got.br_startoff + got.br_blockcount;
4915 	ASSERT(got_endoff >= del_endoff);
4916 	ASSERT(!isnullstartblock(got.br_startblock));
4917 	qfield = 0;
4918 	error = 0;
4919 
4920 	/*
4921 	 * If it's the case where the directory code is running with no block
4922 	 * reservation, and the deleted block is in the middle of its extent,
4923 	 * and the resulting insert of an extent would cause transformation to
4924 	 * btree format, then reject it.  The calling code will then swap blocks
4925 	 * around instead.  We have to do this now, rather than waiting for the
4926 	 * conversion to btree format, since the transaction will be dirty then.
4927 	 */
4928 	if (tp->t_blk_res == 0 &&
4929 	    XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
4930 	    XFS_IFORK_NEXTENTS(ip, whichfork) >=
4931 			XFS_IFORK_MAXEXT(ip, whichfork) &&
4932 	    del->br_startoff > got.br_startoff && del_endoff < got_endoff)
4933 		return -ENOSPC;
4934 
4935 	flags = XFS_ILOG_CORE;
4936 	if (whichfork == XFS_DATA_FORK && XFS_IS_REALTIME_INODE(ip)) {
4937 		xfs_fsblock_t	bno;
4938 		xfs_filblks_t	len;
4939 
4940 		ASSERT(do_mod(del->br_blockcount, mp->m_sb.sb_rextsize) == 0);
4941 		ASSERT(do_mod(del->br_startblock, mp->m_sb.sb_rextsize) == 0);
4942 		bno = del->br_startblock;
4943 		len = del->br_blockcount;
4944 		do_div(bno, mp->m_sb.sb_rextsize);
4945 		do_div(len, mp->m_sb.sb_rextsize);
4946 		error = xfs_rtfree_extent(tp, bno, (xfs_extlen_t)len);
4947 		if (error)
4948 			goto done;
4949 		do_fx = 0;
4950 		nblks = len * mp->m_sb.sb_rextsize;
4951 		qfield = XFS_TRANS_DQ_RTBCOUNT;
4952 	} else {
4953 		do_fx = 1;
4954 		nblks = del->br_blockcount;
4955 		qfield = XFS_TRANS_DQ_BCOUNT;
4956 	}
4957 
4958 	del_endblock = del->br_startblock + del->br_blockcount;
4959 	if (cur) {
4960 		error = xfs_bmbt_lookup_eq(cur, &got, &i);
4961 		if (error)
4962 			goto done;
4963 		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
4964 	}
4965 
4966 	if (got.br_startoff == del->br_startoff)
4967 		state |= BMAP_LEFT_FILLING;
4968 	if (got_endoff == del_endoff)
4969 		state |= BMAP_RIGHT_FILLING;
4970 
4971 	switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
4972 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
4973 		/*
4974 		 * Matches the whole extent.  Delete the entry.
4975 		 */
4976 		xfs_iext_remove(ip, icur, state);
4977 		xfs_iext_prev(ifp, icur);
4978 		XFS_IFORK_NEXT_SET(ip, whichfork,
4979 			XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
4980 		flags |= XFS_ILOG_CORE;
4981 		if (!cur) {
4982 			flags |= xfs_ilog_fext(whichfork);
4983 			break;
4984 		}
4985 		if ((error = xfs_btree_delete(cur, &i)))
4986 			goto done;
4987 		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
4988 		break;
4989 	case BMAP_LEFT_FILLING:
4990 		/*
4991 		 * Deleting the first part of the extent.
4992 		 */
4993 		got.br_startoff = del_endoff;
4994 		got.br_startblock = del_endblock;
4995 		got.br_blockcount -= del->br_blockcount;
4996 		xfs_iext_update_extent(ip, state, icur, &got);
4997 		if (!cur) {
4998 			flags |= xfs_ilog_fext(whichfork);
4999 			break;
5000 		}
5001 		error = xfs_bmbt_update(cur, &got);
5002 		if (error)
5003 			goto done;
5004 		break;
5005 	case BMAP_RIGHT_FILLING:
5006 		/*
5007 		 * Deleting the last part of the extent.
5008 		 */
5009 		got.br_blockcount -= del->br_blockcount;
5010 		xfs_iext_update_extent(ip, state, icur, &got);
5011 		if (!cur) {
5012 			flags |= xfs_ilog_fext(whichfork);
5013 			break;
5014 		}
5015 		error = xfs_bmbt_update(cur, &got);
5016 		if (error)
5017 			goto done;
5018 		break;
5019 	case 0:
5020 		/*
5021 		 * Deleting the middle of the extent.
5022 		 */
5023 		old = got;
5024 
5025 		got.br_blockcount = del->br_startoff - got.br_startoff;
5026 		xfs_iext_update_extent(ip, state, icur, &got);
5027 
5028 		new.br_startoff = del_endoff;
5029 		new.br_blockcount = got_endoff - del_endoff;
5030 		new.br_state = got.br_state;
5031 		new.br_startblock = del_endblock;
5032 
5033 		flags |= XFS_ILOG_CORE;
5034 		if (cur) {
5035 			error = xfs_bmbt_update(cur, &got);
5036 			if (error)
5037 				goto done;
5038 			error = xfs_btree_increment(cur, 0, &i);
5039 			if (error)
5040 				goto done;
5041 			cur->bc_rec.b = new;
5042 			error = xfs_btree_insert(cur, &i);
5043 			if (error && error != -ENOSPC)
5044 				goto done;
5045 			/*
5046 			 * If get no-space back from btree insert, it tried a
5047 			 * split, and we have a zero block reservation.  Fix up
5048 			 * our state and return the error.
5049 			 */
5050 			if (error == -ENOSPC) {
5051 				/*
5052 				 * Reset the cursor, don't trust it after any
5053 				 * insert operation.
5054 				 */
5055 				error = xfs_bmbt_lookup_eq(cur, &got, &i);
5056 				if (error)
5057 					goto done;
5058 				XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
5059 				/*
5060 				 * Update the btree record back
5061 				 * to the original value.
5062 				 */
5063 				error = xfs_bmbt_update(cur, &old);
5064 				if (error)
5065 					goto done;
5066 				/*
5067 				 * Reset the extent record back
5068 				 * to the original value.
5069 				 */
5070 				xfs_iext_update_extent(ip, state, icur, &old);
5071 				flags = 0;
5072 				error = -ENOSPC;
5073 				goto done;
5074 			}
5075 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
5076 		} else
5077 			flags |= xfs_ilog_fext(whichfork);
5078 		XFS_IFORK_NEXT_SET(ip, whichfork,
5079 			XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
5080 		xfs_iext_next(ifp, icur);
5081 		xfs_iext_insert(ip, icur, &new, state);
5082 		break;
5083 	}
5084 
5085 	/* remove reverse mapping */
5086 	error = xfs_rmap_unmap_extent(mp, dfops, ip, whichfork, del);
5087 	if (error)
5088 		goto done;
5089 
5090 	/*
5091 	 * If we need to, add to list of extents to delete.
5092 	 */
5093 	if (do_fx && !(bflags & XFS_BMAPI_REMAP)) {
5094 		if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) {
5095 			error = xfs_refcount_decrease_extent(mp, dfops, del);
5096 			if (error)
5097 				goto done;
5098 		} else
5099 			xfs_bmap_add_free(mp, dfops, del->br_startblock,
5100 					del->br_blockcount, NULL);
5101 	}
5102 
5103 	/*
5104 	 * Adjust inode # blocks in the file.
5105 	 */
5106 	if (nblks)
5107 		ip->i_d.di_nblocks -= nblks;
5108 	/*
5109 	 * Adjust quota data.
5110 	 */
5111 	if (qfield && !(bflags & XFS_BMAPI_REMAP))
5112 		xfs_trans_mod_dquot_byino(tp, ip, qfield, (long)-nblks);
5113 
5114 done:
5115 	*logflagsp = flags;
5116 	return error;
5117 }
5118 
5119 /*
5120  * Unmap (remove) blocks from a file.
5121  * If nexts is nonzero then the number of extents to remove is limited to
5122  * that value.  If not all extents in the block range can be removed then
5123  * *done is set.
5124  */
5125 int						/* error */
5126 __xfs_bunmapi(
5127 	xfs_trans_t		*tp,		/* transaction pointer */
5128 	struct xfs_inode	*ip,		/* incore inode */
5129 	xfs_fileoff_t		start,		/* first file offset deleted */
5130 	xfs_filblks_t		*rlen,		/* i/o: amount remaining */
5131 	int			flags,		/* misc flags */
5132 	xfs_extnum_t		nexts,		/* number of extents max */
5133 	xfs_fsblock_t		*firstblock,	/* first allocated block
5134 						   controls a.g. for allocs */
5135 	struct xfs_defer_ops	*dfops)		/* i/o: deferred updates */
5136 {
5137 	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
5138 	xfs_bmbt_irec_t		del;		/* extent being deleted */
5139 	int			error;		/* error return value */
5140 	xfs_extnum_t		extno;		/* extent number in list */
5141 	xfs_bmbt_irec_t		got;		/* current extent record */
5142 	xfs_ifork_t		*ifp;		/* inode fork pointer */
5143 	int			isrt;		/* freeing in rt area */
5144 	int			logflags;	/* transaction logging flags */
5145 	xfs_extlen_t		mod;		/* rt extent offset */
5146 	xfs_mount_t		*mp;		/* mount structure */
5147 	int			tmp_logflags;	/* partial logging flags */
5148 	int			wasdel;		/* was a delayed alloc extent */
5149 	int			whichfork;	/* data or attribute fork */
5150 	xfs_fsblock_t		sum;
5151 	xfs_filblks_t		len = *rlen;	/* length to unmap in file */
5152 	xfs_fileoff_t		max_len;
5153 	xfs_agnumber_t		prev_agno = NULLAGNUMBER, agno;
5154 	xfs_fileoff_t		end;
5155 	struct xfs_iext_cursor	icur;
5156 	bool			done = false;
5157 
5158 	trace_xfs_bunmap(ip, start, len, flags, _RET_IP_);
5159 
5160 	whichfork = xfs_bmapi_whichfork(flags);
5161 	ASSERT(whichfork != XFS_COW_FORK);
5162 	ifp = XFS_IFORK_PTR(ip, whichfork);
5163 	if (unlikely(
5164 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
5165 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
5166 		XFS_ERROR_REPORT("xfs_bunmapi", XFS_ERRLEVEL_LOW,
5167 				 ip->i_mount);
5168 		return -EFSCORRUPTED;
5169 	}
5170 	mp = ip->i_mount;
5171 	if (XFS_FORCED_SHUTDOWN(mp))
5172 		return -EIO;
5173 
5174 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5175 	ASSERT(len > 0);
5176 	ASSERT(nexts >= 0);
5177 
5178 	/*
5179 	 * Guesstimate how many blocks we can unmap without running the risk of
5180 	 * blowing out the transaction with a mix of EFIs and reflink
5181 	 * adjustments.
5182 	 */
5183 	if (tp && xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK)
5184 		max_len = min(len, xfs_refcount_max_unmap(tp->t_log_res));
5185 	else
5186 		max_len = len;
5187 
5188 	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
5189 	    (error = xfs_iread_extents(tp, ip, whichfork)))
5190 		return error;
5191 	if (xfs_iext_count(ifp) == 0) {
5192 		*rlen = 0;
5193 		return 0;
5194 	}
5195 	XFS_STATS_INC(mp, xs_blk_unmap);
5196 	isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
5197 	end = start + len;
5198 
5199 	if (!xfs_iext_lookup_extent_before(ip, ifp, &end, &icur, &got)) {
5200 		*rlen = 0;
5201 		return 0;
5202 	}
5203 	end--;
5204 
5205 	logflags = 0;
5206 	if (ifp->if_flags & XFS_IFBROOT) {
5207 		ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
5208 		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5209 		cur->bc_private.b.firstblock = *firstblock;
5210 		cur->bc_private.b.dfops = dfops;
5211 		cur->bc_private.b.flags = 0;
5212 	} else
5213 		cur = NULL;
5214 
5215 	if (isrt) {
5216 		/*
5217 		 * Synchronize by locking the bitmap inode.
5218 		 */
5219 		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
5220 		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
5221 		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
5222 		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
5223 	}
5224 
5225 	extno = 0;
5226 	while (end != (xfs_fileoff_t)-1 && end >= start &&
5227 	       (nexts == 0 || extno < nexts) && max_len > 0) {
5228 		/*
5229 		 * Is the found extent after a hole in which end lives?
5230 		 * Just back up to the previous extent, if so.
5231 		 */
5232 		if (got.br_startoff > end &&
5233 		    !xfs_iext_prev_extent(ifp, &icur, &got)) {
5234 			done = true;
5235 			break;
5236 		}
5237 		/*
5238 		 * Is the last block of this extent before the range
5239 		 * we're supposed to delete?  If so, we're done.
5240 		 */
5241 		end = XFS_FILEOFF_MIN(end,
5242 			got.br_startoff + got.br_blockcount - 1);
5243 		if (end < start)
5244 			break;
5245 		/*
5246 		 * Then deal with the (possibly delayed) allocated space
5247 		 * we found.
5248 		 */
5249 		del = got;
5250 		wasdel = isnullstartblock(del.br_startblock);
5251 
5252 		/*
5253 		 * Make sure we don't touch multiple AGF headers out of order
5254 		 * in a single transaction, as that could cause AB-BA deadlocks.
5255 		 */
5256 		if (!wasdel) {
5257 			agno = XFS_FSB_TO_AGNO(mp, del.br_startblock);
5258 			if (prev_agno != NULLAGNUMBER && prev_agno > agno)
5259 				break;
5260 			prev_agno = agno;
5261 		}
5262 		if (got.br_startoff < start) {
5263 			del.br_startoff = start;
5264 			del.br_blockcount -= start - got.br_startoff;
5265 			if (!wasdel)
5266 				del.br_startblock += start - got.br_startoff;
5267 		}
5268 		if (del.br_startoff + del.br_blockcount > end + 1)
5269 			del.br_blockcount = end + 1 - del.br_startoff;
5270 
5271 		/* How much can we safely unmap? */
5272 		if (max_len < del.br_blockcount) {
5273 			del.br_startoff += del.br_blockcount - max_len;
5274 			if (!wasdel)
5275 				del.br_startblock += del.br_blockcount - max_len;
5276 			del.br_blockcount = max_len;
5277 		}
5278 
5279 		sum = del.br_startblock + del.br_blockcount;
5280 		if (isrt &&
5281 		    (mod = do_mod(sum, mp->m_sb.sb_rextsize))) {
5282 			/*
5283 			 * Realtime extent not lined up at the end.
5284 			 * The extent could have been split into written
5285 			 * and unwritten pieces, or we could just be
5286 			 * unmapping part of it.  But we can't really
5287 			 * get rid of part of a realtime extent.
5288 			 */
5289 			if (del.br_state == XFS_EXT_UNWRITTEN ||
5290 			    !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
5291 				/*
5292 				 * This piece is unwritten, or we're not
5293 				 * using unwritten extents.  Skip over it.
5294 				 */
5295 				ASSERT(end >= mod);
5296 				end -= mod > del.br_blockcount ?
5297 					del.br_blockcount : mod;
5298 				if (end < got.br_startoff &&
5299 				    !xfs_iext_prev_extent(ifp, &icur, &got)) {
5300 					done = true;
5301 					break;
5302 				}
5303 				continue;
5304 			}
5305 			/*
5306 			 * It's written, turn it unwritten.
5307 			 * This is better than zeroing it.
5308 			 */
5309 			ASSERT(del.br_state == XFS_EXT_NORM);
5310 			ASSERT(tp->t_blk_res > 0);
5311 			/*
5312 			 * If this spans a realtime extent boundary,
5313 			 * chop it back to the start of the one we end at.
5314 			 */
5315 			if (del.br_blockcount > mod) {
5316 				del.br_startoff += del.br_blockcount - mod;
5317 				del.br_startblock += del.br_blockcount - mod;
5318 				del.br_blockcount = mod;
5319 			}
5320 			del.br_state = XFS_EXT_UNWRITTEN;
5321 			error = xfs_bmap_add_extent_unwritten_real(tp, ip,
5322 					whichfork, &icur, &cur, &del,
5323 					firstblock, dfops, &logflags);
5324 			if (error)
5325 				goto error0;
5326 			goto nodelete;
5327 		}
5328 		if (isrt && (mod = do_mod(del.br_startblock, mp->m_sb.sb_rextsize))) {
5329 			/*
5330 			 * Realtime extent is lined up at the end but not
5331 			 * at the front.  We'll get rid of full extents if
5332 			 * we can.
5333 			 */
5334 			mod = mp->m_sb.sb_rextsize - mod;
5335 			if (del.br_blockcount > mod) {
5336 				del.br_blockcount -= mod;
5337 				del.br_startoff += mod;
5338 				del.br_startblock += mod;
5339 			} else if ((del.br_startoff == start &&
5340 				    (del.br_state == XFS_EXT_UNWRITTEN ||
5341 				     tp->t_blk_res == 0)) ||
5342 				   !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
5343 				/*
5344 				 * Can't make it unwritten.  There isn't
5345 				 * a full extent here so just skip it.
5346 				 */
5347 				ASSERT(end >= del.br_blockcount);
5348 				end -= del.br_blockcount;
5349 				if (got.br_startoff > end &&
5350 				    !xfs_iext_prev_extent(ifp, &icur, &got)) {
5351 					done = true;
5352 					break;
5353 				}
5354 				continue;
5355 			} else if (del.br_state == XFS_EXT_UNWRITTEN) {
5356 				struct xfs_bmbt_irec	prev;
5357 
5358 				/*
5359 				 * This one is already unwritten.
5360 				 * It must have a written left neighbor.
5361 				 * Unwrite the killed part of that one and
5362 				 * try again.
5363 				 */
5364 				if (!xfs_iext_prev_extent(ifp, &icur, &prev))
5365 					ASSERT(0);
5366 				ASSERT(prev.br_state == XFS_EXT_NORM);
5367 				ASSERT(!isnullstartblock(prev.br_startblock));
5368 				ASSERT(del.br_startblock ==
5369 				       prev.br_startblock + prev.br_blockcount);
5370 				if (prev.br_startoff < start) {
5371 					mod = start - prev.br_startoff;
5372 					prev.br_blockcount -= mod;
5373 					prev.br_startblock += mod;
5374 					prev.br_startoff = start;
5375 				}
5376 				prev.br_state = XFS_EXT_UNWRITTEN;
5377 				error = xfs_bmap_add_extent_unwritten_real(tp,
5378 						ip, whichfork, &icur, &cur,
5379 						&prev, firstblock, dfops,
5380 						&logflags);
5381 				if (error)
5382 					goto error0;
5383 				goto nodelete;
5384 			} else {
5385 				ASSERT(del.br_state == XFS_EXT_NORM);
5386 				del.br_state = XFS_EXT_UNWRITTEN;
5387 				error = xfs_bmap_add_extent_unwritten_real(tp,
5388 						ip, whichfork, &icur, &cur,
5389 						&del, firstblock, dfops,
5390 						&logflags);
5391 				if (error)
5392 					goto error0;
5393 				goto nodelete;
5394 			}
5395 		}
5396 
5397 		if (wasdel) {
5398 			error = xfs_bmap_del_extent_delay(ip, whichfork, &icur,
5399 					&got, &del);
5400 		} else {
5401 			error = xfs_bmap_del_extent_real(ip, tp, &icur, dfops,
5402 					cur, &del, &tmp_logflags, whichfork,
5403 					flags);
5404 			logflags |= tmp_logflags;
5405 		}
5406 
5407 		if (error)
5408 			goto error0;
5409 
5410 		max_len -= del.br_blockcount;
5411 		end = del.br_startoff - 1;
5412 nodelete:
5413 		/*
5414 		 * If not done go on to the next (previous) record.
5415 		 */
5416 		if (end != (xfs_fileoff_t)-1 && end >= start) {
5417 			if (!xfs_iext_get_extent(ifp, &icur, &got) ||
5418 			    (got.br_startoff > end &&
5419 			     !xfs_iext_prev_extent(ifp, &icur, &got))) {
5420 				done = true;
5421 				break;
5422 			}
5423 			extno++;
5424 		}
5425 	}
5426 	if (done || end == (xfs_fileoff_t)-1 || end < start)
5427 		*rlen = 0;
5428 	else
5429 		*rlen = end - start + 1;
5430 
5431 	/*
5432 	 * Convert to a btree if necessary.
5433 	 */
5434 	if (xfs_bmap_needs_btree(ip, whichfork)) {
5435 		ASSERT(cur == NULL);
5436 		error = xfs_bmap_extents_to_btree(tp, ip, firstblock, dfops,
5437 			&cur, 0, &tmp_logflags, whichfork);
5438 		logflags |= tmp_logflags;
5439 		if (error)
5440 			goto error0;
5441 	}
5442 	/*
5443 	 * transform from btree to extents, give it cur
5444 	 */
5445 	else if (xfs_bmap_wants_extents(ip, whichfork)) {
5446 		ASSERT(cur != NULL);
5447 		error = xfs_bmap_btree_to_extents(tp, ip, cur, &tmp_logflags,
5448 			whichfork);
5449 		logflags |= tmp_logflags;
5450 		if (error)
5451 			goto error0;
5452 	}
5453 	/*
5454 	 * transform from extents to local?
5455 	 */
5456 	error = 0;
5457 error0:
5458 	/*
5459 	 * Log everything.  Do this after conversion, there's no point in
5460 	 * logging the extent records if we've converted to btree format.
5461 	 */
5462 	if ((logflags & xfs_ilog_fext(whichfork)) &&
5463 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
5464 		logflags &= ~xfs_ilog_fext(whichfork);
5465 	else if ((logflags & xfs_ilog_fbroot(whichfork)) &&
5466 		 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
5467 		logflags &= ~xfs_ilog_fbroot(whichfork);
5468 	/*
5469 	 * Log inode even in the error case, if the transaction
5470 	 * is dirty we'll need to shut down the filesystem.
5471 	 */
5472 	if (logflags)
5473 		xfs_trans_log_inode(tp, ip, logflags);
5474 	if (cur) {
5475 		if (!error) {
5476 			*firstblock = cur->bc_private.b.firstblock;
5477 			cur->bc_private.b.allocated = 0;
5478 		}
5479 		xfs_btree_del_cursor(cur,
5480 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
5481 	}
5482 	return error;
5483 }
5484 
5485 /* Unmap a range of a file. */
5486 int
5487 xfs_bunmapi(
5488 	xfs_trans_t		*tp,
5489 	struct xfs_inode	*ip,
5490 	xfs_fileoff_t		bno,
5491 	xfs_filblks_t		len,
5492 	int			flags,
5493 	xfs_extnum_t		nexts,
5494 	xfs_fsblock_t		*firstblock,
5495 	struct xfs_defer_ops	*dfops,
5496 	int			*done)
5497 {
5498 	int			error;
5499 
5500 	error = __xfs_bunmapi(tp, ip, bno, &len, flags, nexts, firstblock,
5501 			dfops);
5502 	*done = (len == 0);
5503 	return error;
5504 }
5505 
5506 /*
5507  * Determine whether an extent shift can be accomplished by a merge with the
5508  * extent that precedes the target hole of the shift.
5509  */
5510 STATIC bool
5511 xfs_bmse_can_merge(
5512 	struct xfs_bmbt_irec	*left,	/* preceding extent */
5513 	struct xfs_bmbt_irec	*got,	/* current extent to shift */
5514 	xfs_fileoff_t		shift)	/* shift fsb */
5515 {
5516 	xfs_fileoff_t		startoff;
5517 
5518 	startoff = got->br_startoff - shift;
5519 
5520 	/*
5521 	 * The extent, once shifted, must be adjacent in-file and on-disk with
5522 	 * the preceding extent.
5523 	 */
5524 	if ((left->br_startoff + left->br_blockcount != startoff) ||
5525 	    (left->br_startblock + left->br_blockcount != got->br_startblock) ||
5526 	    (left->br_state != got->br_state) ||
5527 	    (left->br_blockcount + got->br_blockcount > MAXEXTLEN))
5528 		return false;
5529 
5530 	return true;
5531 }
5532 
5533 /*
5534  * A bmap extent shift adjusts the file offset of an extent to fill a preceding
5535  * hole in the file. If an extent shift would result in the extent being fully
5536  * adjacent to the extent that currently precedes the hole, we can merge with
5537  * the preceding extent rather than do the shift.
5538  *
5539  * This function assumes the caller has verified a shift-by-merge is possible
5540  * with the provided extents via xfs_bmse_can_merge().
5541  */
5542 STATIC int
5543 xfs_bmse_merge(
5544 	struct xfs_inode		*ip,
5545 	int				whichfork,
5546 	xfs_fileoff_t			shift,		/* shift fsb */
5547 	struct xfs_iext_cursor		*icur,
5548 	struct xfs_bmbt_irec		*got,		/* extent to shift */
5549 	struct xfs_bmbt_irec		*left,		/* preceding extent */
5550 	struct xfs_btree_cur		*cur,
5551 	int				*logflags,	/* output */
5552 	struct xfs_defer_ops		*dfops)
5553 {
5554 	struct xfs_bmbt_irec		new;
5555 	xfs_filblks_t			blockcount;
5556 	int				error, i;
5557 	struct xfs_mount		*mp = ip->i_mount;
5558 
5559 	blockcount = left->br_blockcount + got->br_blockcount;
5560 
5561 	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
5562 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5563 	ASSERT(xfs_bmse_can_merge(left, got, shift));
5564 
5565 	new = *left;
5566 	new.br_blockcount = blockcount;
5567 
5568 	/*
5569 	 * Update the on-disk extent count, the btree if necessary and log the
5570 	 * inode.
5571 	 */
5572 	XFS_IFORK_NEXT_SET(ip, whichfork,
5573 			   XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
5574 	*logflags |= XFS_ILOG_CORE;
5575 	if (!cur) {
5576 		*logflags |= XFS_ILOG_DEXT;
5577 		goto done;
5578 	}
5579 
5580 	/* lookup and remove the extent to merge */
5581 	error = xfs_bmbt_lookup_eq(cur, got, &i);
5582 	if (error)
5583 		return error;
5584 	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5585 
5586 	error = xfs_btree_delete(cur, &i);
5587 	if (error)
5588 		return error;
5589 	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5590 
5591 	/* lookup and update size of the previous extent */
5592 	error = xfs_bmbt_lookup_eq(cur, left, &i);
5593 	if (error)
5594 		return error;
5595 	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5596 
5597 	error = xfs_bmbt_update(cur, &new);
5598 	if (error)
5599 		return error;
5600 
5601 done:
5602 	xfs_iext_remove(ip, icur, 0);
5603 	xfs_iext_prev(XFS_IFORK_PTR(ip, whichfork), icur);
5604 	xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), icur,
5605 			&new);
5606 
5607 	/* update reverse mapping. rmap functions merge the rmaps for us */
5608 	error = xfs_rmap_unmap_extent(mp, dfops, ip, whichfork, got);
5609 	if (error)
5610 		return error;
5611 	memcpy(&new, got, sizeof(new));
5612 	new.br_startoff = left->br_startoff + left->br_blockcount;
5613 	return xfs_rmap_map_extent(mp, dfops, ip, whichfork, &new);
5614 }
5615 
5616 static int
5617 xfs_bmap_shift_update_extent(
5618 	struct xfs_inode	*ip,
5619 	int			whichfork,
5620 	struct xfs_iext_cursor	*icur,
5621 	struct xfs_bmbt_irec	*got,
5622 	struct xfs_btree_cur	*cur,
5623 	int			*logflags,
5624 	struct xfs_defer_ops	*dfops,
5625 	xfs_fileoff_t		startoff)
5626 {
5627 	struct xfs_mount	*mp = ip->i_mount;
5628 	struct xfs_bmbt_irec	prev = *got;
5629 	int			error, i;
5630 
5631 	*logflags |= XFS_ILOG_CORE;
5632 
5633 	got->br_startoff = startoff;
5634 
5635 	if (cur) {
5636 		error = xfs_bmbt_lookup_eq(cur, &prev, &i);
5637 		if (error)
5638 			return error;
5639 		XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5640 
5641 		error = xfs_bmbt_update(cur, got);
5642 		if (error)
5643 			return error;
5644 	} else {
5645 		*logflags |= XFS_ILOG_DEXT;
5646 	}
5647 
5648 	xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), icur,
5649 			got);
5650 
5651 	/* update reverse mapping */
5652 	error = xfs_rmap_unmap_extent(mp, dfops, ip, whichfork, &prev);
5653 	if (error)
5654 		return error;
5655 	return xfs_rmap_map_extent(mp, dfops, ip, whichfork, got);
5656 }
5657 
5658 int
5659 xfs_bmap_collapse_extents(
5660 	struct xfs_trans	*tp,
5661 	struct xfs_inode	*ip,
5662 	xfs_fileoff_t		*next_fsb,
5663 	xfs_fileoff_t		offset_shift_fsb,
5664 	bool			*done,
5665 	xfs_fileoff_t		stop_fsb,
5666 	xfs_fsblock_t		*firstblock,
5667 	struct xfs_defer_ops	*dfops)
5668 {
5669 	int			whichfork = XFS_DATA_FORK;
5670 	struct xfs_mount	*mp = ip->i_mount;
5671 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
5672 	struct xfs_btree_cur	*cur = NULL;
5673 	struct xfs_bmbt_irec	got, prev;
5674 	struct xfs_iext_cursor	icur;
5675 	xfs_fileoff_t		new_startoff;
5676 	int			error = 0;
5677 	int			logflags = 0;
5678 
5679 	if (unlikely(XFS_TEST_ERROR(
5680 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
5681 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
5682 	     mp, XFS_ERRTAG_BMAPIFORMAT))) {
5683 		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
5684 		return -EFSCORRUPTED;
5685 	}
5686 
5687 	if (XFS_FORCED_SHUTDOWN(mp))
5688 		return -EIO;
5689 
5690 	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL));
5691 
5692 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
5693 		error = xfs_iread_extents(tp, ip, whichfork);
5694 		if (error)
5695 			return error;
5696 	}
5697 
5698 	if (ifp->if_flags & XFS_IFBROOT) {
5699 		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5700 		cur->bc_private.b.firstblock = *firstblock;
5701 		cur->bc_private.b.dfops = dfops;
5702 		cur->bc_private.b.flags = 0;
5703 	}
5704 
5705 	if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, &icur, &got)) {
5706 		*done = true;
5707 		goto del_cursor;
5708 	}
5709 	XFS_WANT_CORRUPTED_GOTO(mp, !isnullstartblock(got.br_startblock),
5710 				del_cursor);
5711 
5712 	new_startoff = got.br_startoff - offset_shift_fsb;
5713 	if (xfs_iext_peek_prev_extent(ifp, &icur, &prev)) {
5714 		if (new_startoff < prev.br_startoff + prev.br_blockcount) {
5715 			error = -EINVAL;
5716 			goto del_cursor;
5717 		}
5718 
5719 		if (xfs_bmse_can_merge(&prev, &got, offset_shift_fsb)) {
5720 			error = xfs_bmse_merge(ip, whichfork, offset_shift_fsb,
5721 					&icur, &got, &prev, cur, &logflags,
5722 					dfops);
5723 			if (error)
5724 				goto del_cursor;
5725 			goto done;
5726 		}
5727 	} else {
5728 		if (got.br_startoff < offset_shift_fsb) {
5729 			error = -EINVAL;
5730 			goto del_cursor;
5731 		}
5732 	}
5733 
5734 	error = xfs_bmap_shift_update_extent(ip, whichfork, &icur, &got, cur,
5735 			&logflags, dfops, new_startoff);
5736 	if (error)
5737 		goto del_cursor;
5738 
5739 done:
5740 	if (!xfs_iext_next_extent(ifp, &icur, &got)) {
5741 		*done = true;
5742 		goto del_cursor;
5743 	}
5744 
5745 	*next_fsb = got.br_startoff;
5746 del_cursor:
5747 	if (cur)
5748 		xfs_btree_del_cursor(cur,
5749 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
5750 	if (logflags)
5751 		xfs_trans_log_inode(tp, ip, logflags);
5752 	return error;
5753 }
5754 
5755 int
5756 xfs_bmap_insert_extents(
5757 	struct xfs_trans	*tp,
5758 	struct xfs_inode	*ip,
5759 	xfs_fileoff_t		*next_fsb,
5760 	xfs_fileoff_t		offset_shift_fsb,
5761 	bool			*done,
5762 	xfs_fileoff_t		stop_fsb,
5763 	xfs_fsblock_t		*firstblock,
5764 	struct xfs_defer_ops	*dfops)
5765 {
5766 	int			whichfork = XFS_DATA_FORK;
5767 	struct xfs_mount	*mp = ip->i_mount;
5768 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
5769 	struct xfs_btree_cur	*cur = NULL;
5770 	struct xfs_bmbt_irec	got, next;
5771 	struct xfs_iext_cursor	icur;
5772 	xfs_fileoff_t		new_startoff;
5773 	int			error = 0;
5774 	int			logflags = 0;
5775 
5776 	if (unlikely(XFS_TEST_ERROR(
5777 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
5778 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
5779 	     mp, XFS_ERRTAG_BMAPIFORMAT))) {
5780 		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
5781 		return -EFSCORRUPTED;
5782 	}
5783 
5784 	if (XFS_FORCED_SHUTDOWN(mp))
5785 		return -EIO;
5786 
5787 	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL));
5788 
5789 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
5790 		error = xfs_iread_extents(tp, ip, whichfork);
5791 		if (error)
5792 			return error;
5793 	}
5794 
5795 	if (ifp->if_flags & XFS_IFBROOT) {
5796 		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5797 		cur->bc_private.b.firstblock = *firstblock;
5798 		cur->bc_private.b.dfops = dfops;
5799 		cur->bc_private.b.flags = 0;
5800 	}
5801 
5802 	if (*next_fsb == NULLFSBLOCK) {
5803 		xfs_iext_last(ifp, &icur);
5804 		if (!xfs_iext_get_extent(ifp, &icur, &got) ||
5805 		    stop_fsb > got.br_startoff) {
5806 			*done = true;
5807 			goto del_cursor;
5808 		}
5809 	} else {
5810 		if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, &icur, &got)) {
5811 			*done = true;
5812 			goto del_cursor;
5813 		}
5814 	}
5815 	XFS_WANT_CORRUPTED_GOTO(mp, !isnullstartblock(got.br_startblock),
5816 				del_cursor);
5817 
5818 	if (stop_fsb >= got.br_startoff + got.br_blockcount) {
5819 		error = -EIO;
5820 		goto del_cursor;
5821 	}
5822 
5823 	new_startoff = got.br_startoff + offset_shift_fsb;
5824 	if (xfs_iext_peek_next_extent(ifp, &icur, &next)) {
5825 		if (new_startoff + got.br_blockcount > next.br_startoff) {
5826 			error = -EINVAL;
5827 			goto del_cursor;
5828 		}
5829 
5830 		/*
5831 		 * Unlike a left shift (which involves a hole punch), a right
5832 		 * shift does not modify extent neighbors in any way.  We should
5833 		 * never find mergeable extents in this scenario.  Check anyways
5834 		 * and warn if we encounter two extents that could be one.
5835 		 */
5836 		if (xfs_bmse_can_merge(&got, &next, offset_shift_fsb))
5837 			WARN_ON_ONCE(1);
5838 	}
5839 
5840 	error = xfs_bmap_shift_update_extent(ip, whichfork, &icur, &got, cur,
5841 			&logflags, dfops, new_startoff);
5842 	if (error)
5843 		goto del_cursor;
5844 
5845 	if (!xfs_iext_prev_extent(ifp, &icur, &got) ||
5846 	    stop_fsb >= got.br_startoff + got.br_blockcount) {
5847 		*done = true;
5848 		goto del_cursor;
5849 	}
5850 
5851 	*next_fsb = got.br_startoff;
5852 del_cursor:
5853 	if (cur)
5854 		xfs_btree_del_cursor(cur,
5855 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
5856 	if (logflags)
5857 		xfs_trans_log_inode(tp, ip, logflags);
5858 	return error;
5859 }
5860 
5861 /*
5862  * Splits an extent into two extents at split_fsb block such that it is the
5863  * first block of the current_ext. @ext is a target extent to be split.
5864  * @split_fsb is a block where the extents is split.  If split_fsb lies in a
5865  * hole or the first block of extents, just return 0.
5866  */
5867 STATIC int
5868 xfs_bmap_split_extent_at(
5869 	struct xfs_trans	*tp,
5870 	struct xfs_inode	*ip,
5871 	xfs_fileoff_t		split_fsb,
5872 	xfs_fsblock_t		*firstfsb,
5873 	struct xfs_defer_ops	*dfops)
5874 {
5875 	int				whichfork = XFS_DATA_FORK;
5876 	struct xfs_btree_cur		*cur = NULL;
5877 	struct xfs_bmbt_irec		got;
5878 	struct xfs_bmbt_irec		new; /* split extent */
5879 	struct xfs_mount		*mp = ip->i_mount;
5880 	struct xfs_ifork		*ifp;
5881 	xfs_fsblock_t			gotblkcnt; /* new block count for got */
5882 	struct xfs_iext_cursor		icur;
5883 	int				error = 0;
5884 	int				logflags = 0;
5885 	int				i = 0;
5886 
5887 	if (unlikely(XFS_TEST_ERROR(
5888 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
5889 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
5890 	     mp, XFS_ERRTAG_BMAPIFORMAT))) {
5891 		XFS_ERROR_REPORT("xfs_bmap_split_extent_at",
5892 				 XFS_ERRLEVEL_LOW, mp);
5893 		return -EFSCORRUPTED;
5894 	}
5895 
5896 	if (XFS_FORCED_SHUTDOWN(mp))
5897 		return -EIO;
5898 
5899 	ifp = XFS_IFORK_PTR(ip, whichfork);
5900 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
5901 		/* Read in all the extents */
5902 		error = xfs_iread_extents(tp, ip, whichfork);
5903 		if (error)
5904 			return error;
5905 	}
5906 
5907 	/*
5908 	 * If there are not extents, or split_fsb lies in a hole we are done.
5909 	 */
5910 	if (!xfs_iext_lookup_extent(ip, ifp, split_fsb, &icur, &got) ||
5911 	    got.br_startoff >= split_fsb)
5912 		return 0;
5913 
5914 	gotblkcnt = split_fsb - got.br_startoff;
5915 	new.br_startoff = split_fsb;
5916 	new.br_startblock = got.br_startblock + gotblkcnt;
5917 	new.br_blockcount = got.br_blockcount - gotblkcnt;
5918 	new.br_state = got.br_state;
5919 
5920 	if (ifp->if_flags & XFS_IFBROOT) {
5921 		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5922 		cur->bc_private.b.firstblock = *firstfsb;
5923 		cur->bc_private.b.dfops = dfops;
5924 		cur->bc_private.b.flags = 0;
5925 		error = xfs_bmbt_lookup_eq(cur, &got, &i);
5926 		if (error)
5927 			goto del_cursor;
5928 		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
5929 	}
5930 
5931 	got.br_blockcount = gotblkcnt;
5932 	xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), &icur,
5933 			&got);
5934 
5935 	logflags = XFS_ILOG_CORE;
5936 	if (cur) {
5937 		error = xfs_bmbt_update(cur, &got);
5938 		if (error)
5939 			goto del_cursor;
5940 	} else
5941 		logflags |= XFS_ILOG_DEXT;
5942 
5943 	/* Add new extent */
5944 	xfs_iext_next(ifp, &icur);
5945 	xfs_iext_insert(ip, &icur, &new, 0);
5946 	XFS_IFORK_NEXT_SET(ip, whichfork,
5947 			   XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
5948 
5949 	if (cur) {
5950 		error = xfs_bmbt_lookup_eq(cur, &new, &i);
5951 		if (error)
5952 			goto del_cursor;
5953 		XFS_WANT_CORRUPTED_GOTO(mp, i == 0, del_cursor);
5954 		error = xfs_btree_insert(cur, &i);
5955 		if (error)
5956 			goto del_cursor;
5957 		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
5958 	}
5959 
5960 	/*
5961 	 * Convert to a btree if necessary.
5962 	 */
5963 	if (xfs_bmap_needs_btree(ip, whichfork)) {
5964 		int tmp_logflags; /* partial log flag return val */
5965 
5966 		ASSERT(cur == NULL);
5967 		error = xfs_bmap_extents_to_btree(tp, ip, firstfsb, dfops,
5968 				&cur, 0, &tmp_logflags, whichfork);
5969 		logflags |= tmp_logflags;
5970 	}
5971 
5972 del_cursor:
5973 	if (cur) {
5974 		cur->bc_private.b.allocated = 0;
5975 		xfs_btree_del_cursor(cur,
5976 				error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
5977 	}
5978 
5979 	if (logflags)
5980 		xfs_trans_log_inode(tp, ip, logflags);
5981 	return error;
5982 }
5983 
5984 int
5985 xfs_bmap_split_extent(
5986 	struct xfs_inode        *ip,
5987 	xfs_fileoff_t           split_fsb)
5988 {
5989 	struct xfs_mount        *mp = ip->i_mount;
5990 	struct xfs_trans        *tp;
5991 	struct xfs_defer_ops    dfops;
5992 	xfs_fsblock_t           firstfsb;
5993 	int                     error;
5994 
5995 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write,
5996 			XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp);
5997 	if (error)
5998 		return error;
5999 
6000 	xfs_ilock(ip, XFS_ILOCK_EXCL);
6001 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
6002 
6003 	xfs_defer_init(&dfops, &firstfsb);
6004 
6005 	error = xfs_bmap_split_extent_at(tp, ip, split_fsb,
6006 			&firstfsb, &dfops);
6007 	if (error)
6008 		goto out;
6009 
6010 	error = xfs_defer_finish(&tp, &dfops);
6011 	if (error)
6012 		goto out;
6013 
6014 	return xfs_trans_commit(tp);
6015 
6016 out:
6017 	xfs_defer_cancel(&dfops);
6018 	xfs_trans_cancel(tp);
6019 	return error;
6020 }
6021 
6022 /* Deferred mapping is only for real extents in the data fork. */
6023 static bool
6024 xfs_bmap_is_update_needed(
6025 	struct xfs_bmbt_irec	*bmap)
6026 {
6027 	return  bmap->br_startblock != HOLESTARTBLOCK &&
6028 		bmap->br_startblock != DELAYSTARTBLOCK;
6029 }
6030 
6031 /* Record a bmap intent. */
6032 static int
6033 __xfs_bmap_add(
6034 	struct xfs_mount		*mp,
6035 	struct xfs_defer_ops		*dfops,
6036 	enum xfs_bmap_intent_type	type,
6037 	struct xfs_inode		*ip,
6038 	int				whichfork,
6039 	struct xfs_bmbt_irec		*bmap)
6040 {
6041 	int				error;
6042 	struct xfs_bmap_intent		*bi;
6043 
6044 	trace_xfs_bmap_defer(mp,
6045 			XFS_FSB_TO_AGNO(mp, bmap->br_startblock),
6046 			type,
6047 			XFS_FSB_TO_AGBNO(mp, bmap->br_startblock),
6048 			ip->i_ino, whichfork,
6049 			bmap->br_startoff,
6050 			bmap->br_blockcount,
6051 			bmap->br_state);
6052 
6053 	bi = kmem_alloc(sizeof(struct xfs_bmap_intent), KM_SLEEP | KM_NOFS);
6054 	INIT_LIST_HEAD(&bi->bi_list);
6055 	bi->bi_type = type;
6056 	bi->bi_owner = ip;
6057 	bi->bi_whichfork = whichfork;
6058 	bi->bi_bmap = *bmap;
6059 
6060 	error = xfs_defer_ijoin(dfops, bi->bi_owner);
6061 	if (error) {
6062 		kmem_free(bi);
6063 		return error;
6064 	}
6065 
6066 	xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list);
6067 	return 0;
6068 }
6069 
6070 /* Map an extent into a file. */
6071 int
6072 xfs_bmap_map_extent(
6073 	struct xfs_mount	*mp,
6074 	struct xfs_defer_ops	*dfops,
6075 	struct xfs_inode	*ip,
6076 	struct xfs_bmbt_irec	*PREV)
6077 {
6078 	if (!xfs_bmap_is_update_needed(PREV))
6079 		return 0;
6080 
6081 	return __xfs_bmap_add(mp, dfops, XFS_BMAP_MAP, ip,
6082 			XFS_DATA_FORK, PREV);
6083 }
6084 
6085 /* Unmap an extent out of a file. */
6086 int
6087 xfs_bmap_unmap_extent(
6088 	struct xfs_mount	*mp,
6089 	struct xfs_defer_ops	*dfops,
6090 	struct xfs_inode	*ip,
6091 	struct xfs_bmbt_irec	*PREV)
6092 {
6093 	if (!xfs_bmap_is_update_needed(PREV))
6094 		return 0;
6095 
6096 	return __xfs_bmap_add(mp, dfops, XFS_BMAP_UNMAP, ip,
6097 			XFS_DATA_FORK, PREV);
6098 }
6099 
6100 /*
6101  * Process one of the deferred bmap operations.  We pass back the
6102  * btree cursor to maintain our lock on the bmapbt between calls.
6103  */
6104 int
6105 xfs_bmap_finish_one(
6106 	struct xfs_trans		*tp,
6107 	struct xfs_defer_ops		*dfops,
6108 	struct xfs_inode		*ip,
6109 	enum xfs_bmap_intent_type	type,
6110 	int				whichfork,
6111 	xfs_fileoff_t			startoff,
6112 	xfs_fsblock_t			startblock,
6113 	xfs_filblks_t			*blockcount,
6114 	xfs_exntst_t			state)
6115 {
6116 	xfs_fsblock_t			firstfsb;
6117 	int				error = 0;
6118 
6119 	/*
6120 	 * firstfsb is tied to the transaction lifetime and is used to
6121 	 * ensure correct AG locking order and schedule work item
6122 	 * continuations.  XFS_BUI_MAX_FAST_EXTENTS (== 1) restricts us
6123 	 * to only making one bmap call per transaction, so it should
6124 	 * be safe to have it as a local variable here.
6125 	 */
6126 	firstfsb = NULLFSBLOCK;
6127 
6128 	trace_xfs_bmap_deferred(tp->t_mountp,
6129 			XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
6130 			XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
6131 			ip->i_ino, whichfork, startoff, *blockcount, state);
6132 
6133 	if (WARN_ON_ONCE(whichfork != XFS_DATA_FORK))
6134 		return -EFSCORRUPTED;
6135 
6136 	if (XFS_TEST_ERROR(false, tp->t_mountp,
6137 			XFS_ERRTAG_BMAP_FINISH_ONE))
6138 		return -EIO;
6139 
6140 	switch (type) {
6141 	case XFS_BMAP_MAP:
6142 		error = xfs_bmapi_remap(tp, ip, startoff, *blockcount,
6143 				startblock, dfops);
6144 		*blockcount = 0;
6145 		break;
6146 	case XFS_BMAP_UNMAP:
6147 		error = __xfs_bunmapi(tp, ip, startoff, blockcount,
6148 				XFS_BMAPI_REMAP, 1, &firstfsb, dfops);
6149 		break;
6150 	default:
6151 		ASSERT(0);
6152 		error = -EFSCORRUPTED;
6153 	}
6154 
6155 	return error;
6156 }
6157