xref: /openbmc/linux/fs/xfs/libxfs/xfs_bmap.c (revision bd336e63)
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_error.h"
42 #include "xfs_quota.h"
43 #include "xfs_trans_space.h"
44 #include "xfs_buf_item.h"
45 #include "xfs_trace.h"
46 #include "xfs_symlink.h"
47 #include "xfs_attr_leaf.h"
48 #include "xfs_filestream.h"
49 #include "xfs_rmap.h"
50 #include "xfs_ag_resv.h"
51 #include "xfs_refcount.h"
52 
53 
54 kmem_zone_t		*xfs_bmap_free_item_zone;
55 
56 /*
57  * Miscellaneous helper functions
58  */
59 
60 /*
61  * Compute and fill in the value of the maximum depth of a bmap btree
62  * in this filesystem.  Done once, during mount.
63  */
64 void
65 xfs_bmap_compute_maxlevels(
66 	xfs_mount_t	*mp,		/* file system mount structure */
67 	int		whichfork)	/* data or attr fork */
68 {
69 	int		level;		/* btree level */
70 	uint		maxblocks;	/* max blocks at this level */
71 	uint		maxleafents;	/* max leaf entries possible */
72 	int		maxrootrecs;	/* max records in root block */
73 	int		minleafrecs;	/* min records in leaf block */
74 	int		minnoderecs;	/* min records in node block */
75 	int		sz;		/* root block size */
76 
77 	/*
78 	 * The maximum number of extents in a file, hence the maximum
79 	 * number of leaf entries, is controlled by the type of di_nextents
80 	 * (a signed 32-bit number, xfs_extnum_t), or by di_anextents
81 	 * (a signed 16-bit number, xfs_aextnum_t).
82 	 *
83 	 * Note that we can no longer assume that if we are in ATTR1 that
84 	 * the fork offset of all the inodes will be
85 	 * (xfs_default_attroffset(ip) >> 3) because we could have mounted
86 	 * with ATTR2 and then mounted back with ATTR1, keeping the
87 	 * di_forkoff's fixed but probably at various positions. Therefore,
88 	 * for both ATTR1 and ATTR2 we have to assume the worst case scenario
89 	 * of a minimum size available.
90 	 */
91 	if (whichfork == XFS_DATA_FORK) {
92 		maxleafents = MAXEXTNUM;
93 		sz = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
94 	} else {
95 		maxleafents = MAXAEXTNUM;
96 		sz = XFS_BMDR_SPACE_CALC(MINABTPTRS);
97 	}
98 	maxrootrecs = xfs_bmdr_maxrecs(sz, 0);
99 	minleafrecs = mp->m_bmap_dmnr[0];
100 	minnoderecs = mp->m_bmap_dmnr[1];
101 	maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
102 	for (level = 1; maxblocks > 1; level++) {
103 		if (maxblocks <= maxrootrecs)
104 			maxblocks = 1;
105 		else
106 			maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
107 	}
108 	mp->m_bm_maxlevels[whichfork] = level;
109 }
110 
111 STATIC int				/* error */
112 xfs_bmbt_lookup_eq(
113 	struct xfs_btree_cur	*cur,
114 	xfs_fileoff_t		off,
115 	xfs_fsblock_t		bno,
116 	xfs_filblks_t		len,
117 	int			*stat)	/* success/failure */
118 {
119 	cur->bc_rec.b.br_startoff = off;
120 	cur->bc_rec.b.br_startblock = bno;
121 	cur->bc_rec.b.br_blockcount = len;
122 	return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
123 }
124 
125 STATIC int				/* error */
126 xfs_bmbt_lookup_ge(
127 	struct xfs_btree_cur	*cur,
128 	xfs_fileoff_t		off,
129 	xfs_fsblock_t		bno,
130 	xfs_filblks_t		len,
131 	int			*stat)	/* success/failure */
132 {
133 	cur->bc_rec.b.br_startoff = off;
134 	cur->bc_rec.b.br_startblock = bno;
135 	cur->bc_rec.b.br_blockcount = len;
136 	return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
137 }
138 
139 /*
140  * Check if the inode needs to be converted to btree format.
141  */
142 static inline bool xfs_bmap_needs_btree(struct xfs_inode *ip, int whichfork)
143 {
144 	return whichfork != XFS_COW_FORK &&
145 		XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
146 		XFS_IFORK_NEXTENTS(ip, whichfork) >
147 			XFS_IFORK_MAXEXT(ip, whichfork);
148 }
149 
150 /*
151  * Check if the inode should be converted to extent format.
152  */
153 static inline bool xfs_bmap_wants_extents(struct xfs_inode *ip, int whichfork)
154 {
155 	return whichfork != XFS_COW_FORK &&
156 		XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE &&
157 		XFS_IFORK_NEXTENTS(ip, whichfork) <=
158 			XFS_IFORK_MAXEXT(ip, whichfork);
159 }
160 
161 /*
162  * Update the record referred to by cur to the value given
163  * by [off, bno, len, state].
164  * This either works (return 0) or gets an EFSCORRUPTED error.
165  */
166 STATIC int
167 xfs_bmbt_update(
168 	struct xfs_btree_cur	*cur,
169 	xfs_fileoff_t		off,
170 	xfs_fsblock_t		bno,
171 	xfs_filblks_t		len,
172 	xfs_exntst_t		state)
173 {
174 	union xfs_btree_rec	rec;
175 
176 	xfs_bmbt_disk_set_allf(&rec.bmbt, off, bno, len, state);
177 	return xfs_btree_update(cur, &rec);
178 }
179 
180 /*
181  * Compute the worst-case number of indirect blocks that will be used
182  * for ip's delayed extent of length "len".
183  */
184 STATIC xfs_filblks_t
185 xfs_bmap_worst_indlen(
186 	xfs_inode_t	*ip,		/* incore inode pointer */
187 	xfs_filblks_t	len)		/* delayed extent length */
188 {
189 	int		level;		/* btree level number */
190 	int		maxrecs;	/* maximum record count at this level */
191 	xfs_mount_t	*mp;		/* mount structure */
192 	xfs_filblks_t	rval;		/* return value */
193 
194 	mp = ip->i_mount;
195 	maxrecs = mp->m_bmap_dmxr[0];
196 	for (level = 0, rval = 0;
197 	     level < XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK);
198 	     level++) {
199 		len += maxrecs - 1;
200 		do_div(len, maxrecs);
201 		rval += len;
202 		if (len == 1)
203 			return rval + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) -
204 				level - 1;
205 		if (level == 0)
206 			maxrecs = mp->m_bmap_dmxr[1];
207 	}
208 	return rval;
209 }
210 
211 /*
212  * Calculate the default attribute fork offset for newly created inodes.
213  */
214 uint
215 xfs_default_attroffset(
216 	struct xfs_inode	*ip)
217 {
218 	struct xfs_mount	*mp = ip->i_mount;
219 	uint			offset;
220 
221 	if (mp->m_sb.sb_inodesize == 256) {
222 		offset = XFS_LITINO(mp, ip->i_d.di_version) -
223 				XFS_BMDR_SPACE_CALC(MINABTPTRS);
224 	} else {
225 		offset = XFS_BMDR_SPACE_CALC(6 * MINABTPTRS);
226 	}
227 
228 	ASSERT(offset < XFS_LITINO(mp, ip->i_d.di_version));
229 	return offset;
230 }
231 
232 /*
233  * Helper routine to reset inode di_forkoff field when switching
234  * attribute fork from local to extent format - we reset it where
235  * possible to make space available for inline data fork extents.
236  */
237 STATIC void
238 xfs_bmap_forkoff_reset(
239 	xfs_inode_t	*ip,
240 	int		whichfork)
241 {
242 	if (whichfork == XFS_ATTR_FORK &&
243 	    ip->i_d.di_format != XFS_DINODE_FMT_DEV &&
244 	    ip->i_d.di_format != XFS_DINODE_FMT_UUID &&
245 	    ip->i_d.di_format != XFS_DINODE_FMT_BTREE) {
246 		uint	dfl_forkoff = xfs_default_attroffset(ip) >> 3;
247 
248 		if (dfl_forkoff > ip->i_d.di_forkoff)
249 			ip->i_d.di_forkoff = dfl_forkoff;
250 	}
251 }
252 
253 #ifdef DEBUG
254 STATIC struct xfs_buf *
255 xfs_bmap_get_bp(
256 	struct xfs_btree_cur	*cur,
257 	xfs_fsblock_t		bno)
258 {
259 	struct xfs_log_item_desc *lidp;
260 	int			i;
261 
262 	if (!cur)
263 		return NULL;
264 
265 	for (i = 0; i < XFS_BTREE_MAXLEVELS; i++) {
266 		if (!cur->bc_bufs[i])
267 			break;
268 		if (XFS_BUF_ADDR(cur->bc_bufs[i]) == bno)
269 			return cur->bc_bufs[i];
270 	}
271 
272 	/* Chase down all the log items to see if the bp is there */
273 	list_for_each_entry(lidp, &cur->bc_tp->t_items, lid_trans) {
274 		struct xfs_buf_log_item	*bip;
275 		bip = (struct xfs_buf_log_item *)lidp->lid_item;
276 		if (bip->bli_item.li_type == XFS_LI_BUF &&
277 		    XFS_BUF_ADDR(bip->bli_buf) == bno)
278 			return bip->bli_buf;
279 	}
280 
281 	return NULL;
282 }
283 
284 STATIC void
285 xfs_check_block(
286 	struct xfs_btree_block	*block,
287 	xfs_mount_t		*mp,
288 	int			root,
289 	short			sz)
290 {
291 	int			i, j, dmxr;
292 	__be64			*pp, *thispa;	/* pointer to block address */
293 	xfs_bmbt_key_t		*prevp, *keyp;
294 
295 	ASSERT(be16_to_cpu(block->bb_level) > 0);
296 
297 	prevp = NULL;
298 	for( i = 1; i <= xfs_btree_get_numrecs(block); i++) {
299 		dmxr = mp->m_bmap_dmxr[0];
300 		keyp = XFS_BMBT_KEY_ADDR(mp, block, i);
301 
302 		if (prevp) {
303 			ASSERT(be64_to_cpu(prevp->br_startoff) <
304 			       be64_to_cpu(keyp->br_startoff));
305 		}
306 		prevp = keyp;
307 
308 		/*
309 		 * Compare the block numbers to see if there are dups.
310 		 */
311 		if (root)
312 			pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, i, sz);
313 		else
314 			pp = XFS_BMBT_PTR_ADDR(mp, block, i, dmxr);
315 
316 		for (j = i+1; j <= be16_to_cpu(block->bb_numrecs); j++) {
317 			if (root)
318 				thispa = XFS_BMAP_BROOT_PTR_ADDR(mp, block, j, sz);
319 			else
320 				thispa = XFS_BMBT_PTR_ADDR(mp, block, j, dmxr);
321 			if (*thispa == *pp) {
322 				xfs_warn(mp, "%s: thispa(%d) == pp(%d) %Ld",
323 					__func__, j, i,
324 					(unsigned long long)be64_to_cpu(*thispa));
325 				panic("%s: ptrs are equal in node\n",
326 					__func__);
327 			}
328 		}
329 	}
330 }
331 
332 /*
333  * Check that the extents for the inode ip are in the right order in all
334  * btree leaves. THis becomes prohibitively expensive for large extent count
335  * files, so don't bother with inodes that have more than 10,000 extents in
336  * them. The btree record ordering checks will still be done, so for such large
337  * bmapbt constructs that is going to catch most corruptions.
338  */
339 STATIC void
340 xfs_bmap_check_leaf_extents(
341 	xfs_btree_cur_t		*cur,	/* btree cursor or null */
342 	xfs_inode_t		*ip,		/* incore inode pointer */
343 	int			whichfork)	/* data or attr fork */
344 {
345 	struct xfs_btree_block	*block;	/* current btree block */
346 	xfs_fsblock_t		bno;	/* block # of "block" */
347 	xfs_buf_t		*bp;	/* buffer for "block" */
348 	int			error;	/* error return value */
349 	xfs_extnum_t		i=0, j;	/* index into the extents list */
350 	xfs_ifork_t		*ifp;	/* fork structure */
351 	int			level;	/* btree level, for checking */
352 	xfs_mount_t		*mp;	/* file system mount structure */
353 	__be64			*pp;	/* pointer to block address */
354 	xfs_bmbt_rec_t		*ep;	/* pointer to current extent */
355 	xfs_bmbt_rec_t		last = {0, 0}; /* last extent in prev block */
356 	xfs_bmbt_rec_t		*nextp;	/* pointer to next extent */
357 	int			bp_release = 0;
358 
359 	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE) {
360 		return;
361 	}
362 
363 	/* skip large extent count inodes */
364 	if (ip->i_d.di_nextents > 10000)
365 		return;
366 
367 	bno = NULLFSBLOCK;
368 	mp = ip->i_mount;
369 	ifp = XFS_IFORK_PTR(ip, whichfork);
370 	block = ifp->if_broot;
371 	/*
372 	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
373 	 */
374 	level = be16_to_cpu(block->bb_level);
375 	ASSERT(level > 0);
376 	xfs_check_block(block, mp, 1, ifp->if_broot_bytes);
377 	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
378 	bno = be64_to_cpu(*pp);
379 
380 	ASSERT(bno != NULLFSBLOCK);
381 	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
382 	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
383 
384 	/*
385 	 * Go down the tree until leaf level is reached, following the first
386 	 * pointer (leftmost) at each level.
387 	 */
388 	while (level-- > 0) {
389 		/* See if buf is in cur first */
390 		bp_release = 0;
391 		bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
392 		if (!bp) {
393 			bp_release = 1;
394 			error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
395 						XFS_BMAP_BTREE_REF,
396 						&xfs_bmbt_buf_ops);
397 			if (error)
398 				goto error_norelse;
399 		}
400 		block = XFS_BUF_TO_BLOCK(bp);
401 		if (level == 0)
402 			break;
403 
404 		/*
405 		 * Check this block for basic sanity (increasing keys and
406 		 * no duplicate blocks).
407 		 */
408 
409 		xfs_check_block(block, mp, 0, 0);
410 		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
411 		bno = be64_to_cpu(*pp);
412 		XFS_WANT_CORRUPTED_GOTO(mp,
413 					XFS_FSB_SANITY_CHECK(mp, bno), error0);
414 		if (bp_release) {
415 			bp_release = 0;
416 			xfs_trans_brelse(NULL, bp);
417 		}
418 	}
419 
420 	/*
421 	 * Here with bp and block set to the leftmost leaf node in the tree.
422 	 */
423 	i = 0;
424 
425 	/*
426 	 * Loop over all leaf nodes checking that all extents are in the right order.
427 	 */
428 	for (;;) {
429 		xfs_fsblock_t	nextbno;
430 		xfs_extnum_t	num_recs;
431 
432 
433 		num_recs = xfs_btree_get_numrecs(block);
434 
435 		/*
436 		 * Read-ahead the next leaf block, if any.
437 		 */
438 
439 		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
440 
441 		/*
442 		 * Check all the extents to make sure they are OK.
443 		 * If we had a previous block, the last entry should
444 		 * conform with the first entry in this one.
445 		 */
446 
447 		ep = XFS_BMBT_REC_ADDR(mp, block, 1);
448 		if (i) {
449 			ASSERT(xfs_bmbt_disk_get_startoff(&last) +
450 			       xfs_bmbt_disk_get_blockcount(&last) <=
451 			       xfs_bmbt_disk_get_startoff(ep));
452 		}
453 		for (j = 1; j < num_recs; j++) {
454 			nextp = XFS_BMBT_REC_ADDR(mp, block, j + 1);
455 			ASSERT(xfs_bmbt_disk_get_startoff(ep) +
456 			       xfs_bmbt_disk_get_blockcount(ep) <=
457 			       xfs_bmbt_disk_get_startoff(nextp));
458 			ep = nextp;
459 		}
460 
461 		last = *ep;
462 		i += num_recs;
463 		if (bp_release) {
464 			bp_release = 0;
465 			xfs_trans_brelse(NULL, bp);
466 		}
467 		bno = nextbno;
468 		/*
469 		 * If we've reached the end, stop.
470 		 */
471 		if (bno == NULLFSBLOCK)
472 			break;
473 
474 		bp_release = 0;
475 		bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
476 		if (!bp) {
477 			bp_release = 1;
478 			error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
479 						XFS_BMAP_BTREE_REF,
480 						&xfs_bmbt_buf_ops);
481 			if (error)
482 				goto error_norelse;
483 		}
484 		block = XFS_BUF_TO_BLOCK(bp);
485 	}
486 
487 	return;
488 
489 error0:
490 	xfs_warn(mp, "%s: at error0", __func__);
491 	if (bp_release)
492 		xfs_trans_brelse(NULL, bp);
493 error_norelse:
494 	xfs_warn(mp, "%s: BAD after btree leaves for %d extents",
495 		__func__, i);
496 	panic("%s: CORRUPTED BTREE OR SOMETHING", __func__);
497 	return;
498 }
499 
500 /*
501  * Add bmap trace insert entries for all the contents of the extent records.
502  */
503 void
504 xfs_bmap_trace_exlist(
505 	xfs_inode_t	*ip,		/* incore inode pointer */
506 	xfs_extnum_t	cnt,		/* count of entries in the list */
507 	int		whichfork,	/* data or attr fork */
508 	unsigned long	caller_ip)
509 {
510 	xfs_extnum_t	idx;		/* extent record index */
511 	xfs_ifork_t	*ifp;		/* inode fork pointer */
512 	int		state = 0;
513 
514 	if (whichfork == XFS_ATTR_FORK)
515 		state |= BMAP_ATTRFORK;
516 
517 	ifp = XFS_IFORK_PTR(ip, whichfork);
518 	ASSERT(cnt == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
519 	for (idx = 0; idx < cnt; idx++)
520 		trace_xfs_extlist(ip, idx, whichfork, caller_ip);
521 }
522 
523 /*
524  * Validate that the bmbt_irecs being returned from bmapi are valid
525  * given the caller's original parameters.  Specifically check the
526  * ranges of the returned irecs to ensure that they only extend beyond
527  * the given parameters if the XFS_BMAPI_ENTIRE flag was set.
528  */
529 STATIC void
530 xfs_bmap_validate_ret(
531 	xfs_fileoff_t		bno,
532 	xfs_filblks_t		len,
533 	int			flags,
534 	xfs_bmbt_irec_t		*mval,
535 	int			nmap,
536 	int			ret_nmap)
537 {
538 	int			i;		/* index to map values */
539 
540 	ASSERT(ret_nmap <= nmap);
541 
542 	for (i = 0; i < ret_nmap; i++) {
543 		ASSERT(mval[i].br_blockcount > 0);
544 		if (!(flags & XFS_BMAPI_ENTIRE)) {
545 			ASSERT(mval[i].br_startoff >= bno);
546 			ASSERT(mval[i].br_blockcount <= len);
547 			ASSERT(mval[i].br_startoff + mval[i].br_blockcount <=
548 			       bno + len);
549 		} else {
550 			ASSERT(mval[i].br_startoff < bno + len);
551 			ASSERT(mval[i].br_startoff + mval[i].br_blockcount >
552 			       bno);
553 		}
554 		ASSERT(i == 0 ||
555 		       mval[i - 1].br_startoff + mval[i - 1].br_blockcount ==
556 		       mval[i].br_startoff);
557 		ASSERT(mval[i].br_startblock != DELAYSTARTBLOCK &&
558 		       mval[i].br_startblock != HOLESTARTBLOCK);
559 		ASSERT(mval[i].br_state == XFS_EXT_NORM ||
560 		       mval[i].br_state == XFS_EXT_UNWRITTEN);
561 	}
562 }
563 
564 #else
565 #define xfs_bmap_check_leaf_extents(cur, ip, whichfork)		do { } while (0)
566 #define	xfs_bmap_validate_ret(bno,len,flags,mval,onmap,nmap)
567 #endif /* DEBUG */
568 
569 /*
570  * bmap free list manipulation functions
571  */
572 
573 /*
574  * Add the extent to the list of extents to be free at transaction end.
575  * The list is maintained sorted (by block number).
576  */
577 void
578 xfs_bmap_add_free(
579 	struct xfs_mount		*mp,
580 	struct xfs_defer_ops		*dfops,
581 	xfs_fsblock_t			bno,
582 	xfs_filblks_t			len,
583 	struct xfs_owner_info		*oinfo)
584 {
585 	struct xfs_extent_free_item	*new;		/* new element */
586 #ifdef DEBUG
587 	xfs_agnumber_t		agno;
588 	xfs_agblock_t		agbno;
589 
590 	ASSERT(bno != NULLFSBLOCK);
591 	ASSERT(len > 0);
592 	ASSERT(len <= MAXEXTLEN);
593 	ASSERT(!isnullstartblock(bno));
594 	agno = XFS_FSB_TO_AGNO(mp, bno);
595 	agbno = XFS_FSB_TO_AGBNO(mp, bno);
596 	ASSERT(agno < mp->m_sb.sb_agcount);
597 	ASSERT(agbno < mp->m_sb.sb_agblocks);
598 	ASSERT(len < mp->m_sb.sb_agblocks);
599 	ASSERT(agbno + len <= mp->m_sb.sb_agblocks);
600 #endif
601 	ASSERT(xfs_bmap_free_item_zone != NULL);
602 
603 	new = kmem_zone_alloc(xfs_bmap_free_item_zone, KM_SLEEP);
604 	new->xefi_startblock = bno;
605 	new->xefi_blockcount = (xfs_extlen_t)len;
606 	if (oinfo)
607 		new->xefi_oinfo = *oinfo;
608 	else
609 		xfs_rmap_skip_owner_update(&new->xefi_oinfo);
610 	trace_xfs_bmap_free_defer(mp, XFS_FSB_TO_AGNO(mp, bno), 0,
611 			XFS_FSB_TO_AGBNO(mp, bno), len);
612 	xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_FREE, &new->xefi_list);
613 }
614 
615 /*
616  * Inode fork format manipulation functions
617  */
618 
619 /*
620  * Transform a btree format file with only one leaf node, where the
621  * extents list will fit in the inode, into an extents format file.
622  * Since the file extents are already in-core, all we have to do is
623  * give up the space for the btree root and pitch the leaf block.
624  */
625 STATIC int				/* error */
626 xfs_bmap_btree_to_extents(
627 	xfs_trans_t		*tp,	/* transaction pointer */
628 	xfs_inode_t		*ip,	/* incore inode pointer */
629 	xfs_btree_cur_t		*cur,	/* btree cursor */
630 	int			*logflagsp, /* inode logging flags */
631 	int			whichfork)  /* data or attr fork */
632 {
633 	/* REFERENCED */
634 	struct xfs_btree_block	*cblock;/* child btree block */
635 	xfs_fsblock_t		cbno;	/* child block number */
636 	xfs_buf_t		*cbp;	/* child block's buffer */
637 	int			error;	/* error return value */
638 	xfs_ifork_t		*ifp;	/* inode fork data */
639 	xfs_mount_t		*mp;	/* mount point structure */
640 	__be64			*pp;	/* ptr to block address */
641 	struct xfs_btree_block	*rblock;/* root btree block */
642 	struct xfs_owner_info	oinfo;
643 
644 	mp = ip->i_mount;
645 	ifp = XFS_IFORK_PTR(ip, whichfork);
646 	ASSERT(whichfork != XFS_COW_FORK);
647 	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
648 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
649 	rblock = ifp->if_broot;
650 	ASSERT(be16_to_cpu(rblock->bb_level) == 1);
651 	ASSERT(be16_to_cpu(rblock->bb_numrecs) == 1);
652 	ASSERT(xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0) == 1);
653 	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, ifp->if_broot_bytes);
654 	cbno = be64_to_cpu(*pp);
655 	*logflagsp = 0;
656 #ifdef DEBUG
657 	if ((error = xfs_btree_check_lptr(cur, cbno, 1)))
658 		return error;
659 #endif
660 	error = xfs_btree_read_bufl(mp, tp, cbno, 0, &cbp, XFS_BMAP_BTREE_REF,
661 				&xfs_bmbt_buf_ops);
662 	if (error)
663 		return error;
664 	cblock = XFS_BUF_TO_BLOCK(cbp);
665 	if ((error = xfs_btree_check_block(cur, cblock, 0, cbp)))
666 		return error;
667 	xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, whichfork);
668 	xfs_bmap_add_free(mp, cur->bc_private.b.dfops, cbno, 1, &oinfo);
669 	ip->i_d.di_nblocks--;
670 	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
671 	xfs_trans_binval(tp, cbp);
672 	if (cur->bc_bufs[0] == cbp)
673 		cur->bc_bufs[0] = NULL;
674 	xfs_iroot_realloc(ip, -1, whichfork);
675 	ASSERT(ifp->if_broot == NULL);
676 	ASSERT((ifp->if_flags & XFS_IFBROOT) == 0);
677 	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
678 	*logflagsp = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
679 	return 0;
680 }
681 
682 /*
683  * Convert an extents-format file into a btree-format file.
684  * The new file will have a root block (in the inode) and a single child block.
685  */
686 STATIC int					/* error */
687 xfs_bmap_extents_to_btree(
688 	xfs_trans_t		*tp,		/* transaction pointer */
689 	xfs_inode_t		*ip,		/* incore inode pointer */
690 	xfs_fsblock_t		*firstblock,	/* first-block-allocated */
691 	struct xfs_defer_ops	*dfops,		/* blocks freed in xaction */
692 	xfs_btree_cur_t		**curp,		/* cursor returned to caller */
693 	int			wasdel,		/* converting a delayed alloc */
694 	int			*logflagsp,	/* inode logging flags */
695 	int			whichfork)	/* data or attr fork */
696 {
697 	struct xfs_btree_block	*ablock;	/* allocated (child) bt block */
698 	xfs_buf_t		*abp;		/* buffer for ablock */
699 	xfs_alloc_arg_t		args;		/* allocation arguments */
700 	xfs_bmbt_rec_t		*arp;		/* child record pointer */
701 	struct xfs_btree_block	*block;		/* btree root block */
702 	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
703 	xfs_bmbt_rec_host_t	*ep;		/* extent record pointer */
704 	int			error;		/* error return value */
705 	xfs_extnum_t		i, cnt;		/* extent record index */
706 	xfs_ifork_t		*ifp;		/* inode fork pointer */
707 	xfs_bmbt_key_t		*kp;		/* root block key pointer */
708 	xfs_mount_t		*mp;		/* mount structure */
709 	xfs_extnum_t		nextents;	/* number of file extents */
710 	xfs_bmbt_ptr_t		*pp;		/* root block address pointer */
711 
712 	mp = ip->i_mount;
713 	ASSERT(whichfork != XFS_COW_FORK);
714 	ifp = XFS_IFORK_PTR(ip, whichfork);
715 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS);
716 
717 	/*
718 	 * Make space in the inode incore.
719 	 */
720 	xfs_iroot_realloc(ip, 1, whichfork);
721 	ifp->if_flags |= XFS_IFBROOT;
722 
723 	/*
724 	 * Fill in the root.
725 	 */
726 	block = ifp->if_broot;
727 	if (xfs_sb_version_hascrc(&mp->m_sb))
728 		xfs_btree_init_block_int(mp, block, XFS_BUF_DADDR_NULL,
729 				 XFS_BMAP_CRC_MAGIC, 1, 1, ip->i_ino,
730 				 XFS_BTREE_LONG_PTRS | XFS_BTREE_CRC_BLOCKS);
731 	else
732 		xfs_btree_init_block_int(mp, block, XFS_BUF_DADDR_NULL,
733 				 XFS_BMAP_MAGIC, 1, 1, ip->i_ino,
734 				 XFS_BTREE_LONG_PTRS);
735 
736 	/*
737 	 * Need a cursor.  Can't allocate until bb_level is filled in.
738 	 */
739 	cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
740 	cur->bc_private.b.firstblock = *firstblock;
741 	cur->bc_private.b.dfops = dfops;
742 	cur->bc_private.b.flags = wasdel ? XFS_BTCUR_BPRV_WASDEL : 0;
743 	/*
744 	 * Convert to a btree with two levels, one record in root.
745 	 */
746 	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_BTREE);
747 	memset(&args, 0, sizeof(args));
748 	args.tp = tp;
749 	args.mp = mp;
750 	xfs_rmap_ino_bmbt_owner(&args.oinfo, ip->i_ino, whichfork);
751 	args.firstblock = *firstblock;
752 	if (*firstblock == NULLFSBLOCK) {
753 		args.type = XFS_ALLOCTYPE_START_BNO;
754 		args.fsbno = XFS_INO_TO_FSB(mp, ip->i_ino);
755 	} else if (dfops->dop_low) {
756 try_another_ag:
757 		args.type = XFS_ALLOCTYPE_START_BNO;
758 		args.fsbno = *firstblock;
759 	} else {
760 		args.type = XFS_ALLOCTYPE_NEAR_BNO;
761 		args.fsbno = *firstblock;
762 	}
763 	args.minlen = args.maxlen = args.prod = 1;
764 	args.wasdel = wasdel;
765 	*logflagsp = 0;
766 	if ((error = xfs_alloc_vextent(&args))) {
767 		xfs_iroot_realloc(ip, -1, whichfork);
768 		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
769 		return error;
770 	}
771 
772 	/*
773 	 * During a CoW operation, the allocation and bmbt updates occur in
774 	 * different transactions.  The mapping code tries to put new bmbt
775 	 * blocks near extents being mapped, but the only way to guarantee this
776 	 * is if the alloc and the mapping happen in a single transaction that
777 	 * has a block reservation.  That isn't the case here, so if we run out
778 	 * of space we'll try again with another AG.
779 	 */
780 	if (xfs_sb_version_hasreflink(&cur->bc_mp->m_sb) &&
781 	    args.fsbno == NULLFSBLOCK &&
782 	    args.type == XFS_ALLOCTYPE_NEAR_BNO) {
783 		dfops->dop_low = true;
784 		goto try_another_ag;
785 	}
786 	/*
787 	 * Allocation can't fail, the space was reserved.
788 	 */
789 	ASSERT(args.fsbno != NULLFSBLOCK);
790 	ASSERT(*firstblock == NULLFSBLOCK ||
791 	       args.agno == XFS_FSB_TO_AGNO(mp, *firstblock) ||
792 	       (dfops->dop_low &&
793 		args.agno > XFS_FSB_TO_AGNO(mp, *firstblock)));
794 	*firstblock = cur->bc_private.b.firstblock = args.fsbno;
795 	cur->bc_private.b.allocated++;
796 	ip->i_d.di_nblocks++;
797 	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, 1L);
798 	abp = xfs_btree_get_bufl(mp, tp, args.fsbno, 0);
799 	/*
800 	 * Fill in the child block.
801 	 */
802 	abp->b_ops = &xfs_bmbt_buf_ops;
803 	ablock = XFS_BUF_TO_BLOCK(abp);
804 	if (xfs_sb_version_hascrc(&mp->m_sb))
805 		xfs_btree_init_block_int(mp, ablock, abp->b_bn,
806 				XFS_BMAP_CRC_MAGIC, 0, 0, ip->i_ino,
807 				XFS_BTREE_LONG_PTRS | XFS_BTREE_CRC_BLOCKS);
808 	else
809 		xfs_btree_init_block_int(mp, ablock, abp->b_bn,
810 				XFS_BMAP_MAGIC, 0, 0, ip->i_ino,
811 				XFS_BTREE_LONG_PTRS);
812 
813 	arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
814 	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
815 	for (cnt = i = 0; i < nextents; i++) {
816 		ep = xfs_iext_get_ext(ifp, i);
817 		if (!isnullstartblock(xfs_bmbt_get_startblock(ep))) {
818 			arp->l0 = cpu_to_be64(ep->l0);
819 			arp->l1 = cpu_to_be64(ep->l1);
820 			arp++; cnt++;
821 		}
822 	}
823 	ASSERT(cnt == XFS_IFORK_NEXTENTS(ip, whichfork));
824 	xfs_btree_set_numrecs(ablock, cnt);
825 
826 	/*
827 	 * Fill in the root key and pointer.
828 	 */
829 	kp = XFS_BMBT_KEY_ADDR(mp, block, 1);
830 	arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
831 	kp->br_startoff = cpu_to_be64(xfs_bmbt_disk_get_startoff(arp));
832 	pp = XFS_BMBT_PTR_ADDR(mp, block, 1, xfs_bmbt_get_maxrecs(cur,
833 						be16_to_cpu(block->bb_level)));
834 	*pp = cpu_to_be64(args.fsbno);
835 
836 	/*
837 	 * Do all this logging at the end so that
838 	 * the root is at the right level.
839 	 */
840 	xfs_btree_log_block(cur, abp, XFS_BB_ALL_BITS);
841 	xfs_btree_log_recs(cur, abp, 1, be16_to_cpu(ablock->bb_numrecs));
842 	ASSERT(*curp == NULL);
843 	*curp = cur;
844 	*logflagsp = XFS_ILOG_CORE | xfs_ilog_fbroot(whichfork);
845 	return 0;
846 }
847 
848 /*
849  * Convert a local file to an extents file.
850  * This code is out of bounds for data forks of regular files,
851  * since the file data needs to get logged so things will stay consistent.
852  * (The bmap-level manipulations are ok, though).
853  */
854 void
855 xfs_bmap_local_to_extents_empty(
856 	struct xfs_inode	*ip,
857 	int			whichfork)
858 {
859 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
860 
861 	ASSERT(whichfork != XFS_COW_FORK);
862 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
863 	ASSERT(ifp->if_bytes == 0);
864 	ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) == 0);
865 
866 	xfs_bmap_forkoff_reset(ip, whichfork);
867 	ifp->if_flags &= ~XFS_IFINLINE;
868 	ifp->if_flags |= XFS_IFEXTENTS;
869 	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
870 }
871 
872 
873 STATIC int				/* error */
874 xfs_bmap_local_to_extents(
875 	xfs_trans_t	*tp,		/* transaction pointer */
876 	xfs_inode_t	*ip,		/* incore inode pointer */
877 	xfs_fsblock_t	*firstblock,	/* first block allocated in xaction */
878 	xfs_extlen_t	total,		/* total blocks needed by transaction */
879 	int		*logflagsp,	/* inode logging flags */
880 	int		whichfork,
881 	void		(*init_fn)(struct xfs_trans *tp,
882 				   struct xfs_buf *bp,
883 				   struct xfs_inode *ip,
884 				   struct xfs_ifork *ifp))
885 {
886 	int		error = 0;
887 	int		flags;		/* logging flags returned */
888 	xfs_ifork_t	*ifp;		/* inode fork pointer */
889 	xfs_alloc_arg_t	args;		/* allocation arguments */
890 	xfs_buf_t	*bp;		/* buffer for extent block */
891 	xfs_bmbt_rec_host_t *ep;	/* extent record pointer */
892 
893 	/*
894 	 * We don't want to deal with the case of keeping inode data inline yet.
895 	 * So sending the data fork of a regular inode is invalid.
896 	 */
897 	ASSERT(!(S_ISREG(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK));
898 	ifp = XFS_IFORK_PTR(ip, whichfork);
899 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
900 
901 	if (!ifp->if_bytes) {
902 		xfs_bmap_local_to_extents_empty(ip, whichfork);
903 		flags = XFS_ILOG_CORE;
904 		goto done;
905 	}
906 
907 	flags = 0;
908 	error = 0;
909 	ASSERT((ifp->if_flags & (XFS_IFINLINE|XFS_IFEXTENTS|XFS_IFEXTIREC)) ==
910 								XFS_IFINLINE);
911 	memset(&args, 0, sizeof(args));
912 	args.tp = tp;
913 	args.mp = ip->i_mount;
914 	xfs_rmap_ino_owner(&args.oinfo, ip->i_ino, whichfork, 0);
915 	args.firstblock = *firstblock;
916 	/*
917 	 * Allocate a block.  We know we need only one, since the
918 	 * file currently fits in an inode.
919 	 */
920 	if (*firstblock == NULLFSBLOCK) {
921 try_another_ag:
922 		args.fsbno = XFS_INO_TO_FSB(args.mp, ip->i_ino);
923 		args.type = XFS_ALLOCTYPE_START_BNO;
924 	} else {
925 		args.fsbno = *firstblock;
926 		args.type = XFS_ALLOCTYPE_NEAR_BNO;
927 	}
928 	args.total = total;
929 	args.minlen = args.maxlen = args.prod = 1;
930 	error = xfs_alloc_vextent(&args);
931 	if (error)
932 		goto done;
933 
934 	/*
935 	 * During a CoW operation, the allocation and bmbt updates occur in
936 	 * different transactions.  The mapping code tries to put new bmbt
937 	 * blocks near extents being mapped, but the only way to guarantee this
938 	 * is if the alloc and the mapping happen in a single transaction that
939 	 * has a block reservation.  That isn't the case here, so if we run out
940 	 * of space we'll try again with another AG.
941 	 */
942 	if (xfs_sb_version_hasreflink(&ip->i_mount->m_sb) &&
943 	    args.fsbno == NULLFSBLOCK &&
944 	    args.type == XFS_ALLOCTYPE_NEAR_BNO) {
945 		goto try_another_ag;
946 	}
947 	/* Can't fail, the space was reserved. */
948 	ASSERT(args.fsbno != NULLFSBLOCK);
949 	ASSERT(args.len == 1);
950 	*firstblock = args.fsbno;
951 	bp = xfs_btree_get_bufl(args.mp, tp, args.fsbno, 0);
952 
953 	/*
954 	 * Initialize the block, copy the data and log the remote buffer.
955 	 *
956 	 * The callout is responsible for logging because the remote format
957 	 * might differ from the local format and thus we don't know how much to
958 	 * log here. Note that init_fn must also set the buffer log item type
959 	 * correctly.
960 	 */
961 	init_fn(tp, bp, ip, ifp);
962 
963 	/* account for the change in fork size */
964 	xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
965 	xfs_bmap_local_to_extents_empty(ip, whichfork);
966 	flags |= XFS_ILOG_CORE;
967 
968 	xfs_iext_add(ifp, 0, 1);
969 	ep = xfs_iext_get_ext(ifp, 0);
970 	xfs_bmbt_set_allf(ep, 0, args.fsbno, 1, XFS_EXT_NORM);
971 	trace_xfs_bmap_post_update(ip, 0,
972 			whichfork == XFS_ATTR_FORK ? BMAP_ATTRFORK : 0,
973 			_THIS_IP_);
974 	XFS_IFORK_NEXT_SET(ip, whichfork, 1);
975 	ip->i_d.di_nblocks = 1;
976 	xfs_trans_mod_dquot_byino(tp, ip,
977 		XFS_TRANS_DQ_BCOUNT, 1L);
978 	flags |= xfs_ilog_fext(whichfork);
979 
980 done:
981 	*logflagsp = flags;
982 	return error;
983 }
984 
985 /*
986  * Called from xfs_bmap_add_attrfork to handle btree format files.
987  */
988 STATIC int					/* error */
989 xfs_bmap_add_attrfork_btree(
990 	xfs_trans_t		*tp,		/* transaction pointer */
991 	xfs_inode_t		*ip,		/* incore inode pointer */
992 	xfs_fsblock_t		*firstblock,	/* first block allocated */
993 	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
994 	int			*flags)		/* inode logging flags */
995 {
996 	xfs_btree_cur_t		*cur;		/* btree cursor */
997 	int			error;		/* error return value */
998 	xfs_mount_t		*mp;		/* file system mount struct */
999 	int			stat;		/* newroot status */
1000 
1001 	mp = ip->i_mount;
1002 	if (ip->i_df.if_broot_bytes <= XFS_IFORK_DSIZE(ip))
1003 		*flags |= XFS_ILOG_DBROOT;
1004 	else {
1005 		cur = xfs_bmbt_init_cursor(mp, tp, ip, XFS_DATA_FORK);
1006 		cur->bc_private.b.dfops = dfops;
1007 		cur->bc_private.b.firstblock = *firstblock;
1008 		if ((error = xfs_bmbt_lookup_ge(cur, 0, 0, 0, &stat)))
1009 			goto error0;
1010 		/* must be at least one entry */
1011 		XFS_WANT_CORRUPTED_GOTO(mp, stat == 1, error0);
1012 		if ((error = xfs_btree_new_iroot(cur, flags, &stat)))
1013 			goto error0;
1014 		if (stat == 0) {
1015 			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1016 			return -ENOSPC;
1017 		}
1018 		*firstblock = cur->bc_private.b.firstblock;
1019 		cur->bc_private.b.allocated = 0;
1020 		xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1021 	}
1022 	return 0;
1023 error0:
1024 	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1025 	return error;
1026 }
1027 
1028 /*
1029  * Called from xfs_bmap_add_attrfork to handle extents format files.
1030  */
1031 STATIC int					/* error */
1032 xfs_bmap_add_attrfork_extents(
1033 	xfs_trans_t		*tp,		/* transaction pointer */
1034 	xfs_inode_t		*ip,		/* incore inode pointer */
1035 	xfs_fsblock_t		*firstblock,	/* first block allocated */
1036 	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
1037 	int			*flags)		/* inode logging flags */
1038 {
1039 	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
1040 	int			error;		/* error return value */
1041 
1042 	if (ip->i_d.di_nextents * sizeof(xfs_bmbt_rec_t) <= XFS_IFORK_DSIZE(ip))
1043 		return 0;
1044 	cur = NULL;
1045 	error = xfs_bmap_extents_to_btree(tp, ip, firstblock, dfops, &cur, 0,
1046 		flags, XFS_DATA_FORK);
1047 	if (cur) {
1048 		cur->bc_private.b.allocated = 0;
1049 		xfs_btree_del_cursor(cur,
1050 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
1051 	}
1052 	return error;
1053 }
1054 
1055 /*
1056  * Called from xfs_bmap_add_attrfork to handle local format files. Each
1057  * different data fork content type needs a different callout to do the
1058  * conversion. Some are basic and only require special block initialisation
1059  * callouts for the data formating, others (directories) are so specialised they
1060  * handle everything themselves.
1061  *
1062  * XXX (dgc): investigate whether directory conversion can use the generic
1063  * formatting callout. It should be possible - it's just a very complex
1064  * formatter.
1065  */
1066 STATIC int					/* error */
1067 xfs_bmap_add_attrfork_local(
1068 	xfs_trans_t		*tp,		/* transaction pointer */
1069 	xfs_inode_t		*ip,		/* incore inode pointer */
1070 	xfs_fsblock_t		*firstblock,	/* first block allocated */
1071 	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
1072 	int			*flags)		/* inode logging flags */
1073 {
1074 	xfs_da_args_t		dargs;		/* args for dir/attr code */
1075 
1076 	if (ip->i_df.if_bytes <= XFS_IFORK_DSIZE(ip))
1077 		return 0;
1078 
1079 	if (S_ISDIR(VFS_I(ip)->i_mode)) {
1080 		memset(&dargs, 0, sizeof(dargs));
1081 		dargs.geo = ip->i_mount->m_dir_geo;
1082 		dargs.dp = ip;
1083 		dargs.firstblock = firstblock;
1084 		dargs.dfops = dfops;
1085 		dargs.total = dargs.geo->fsbcount;
1086 		dargs.whichfork = XFS_DATA_FORK;
1087 		dargs.trans = tp;
1088 		return xfs_dir2_sf_to_block(&dargs);
1089 	}
1090 
1091 	if (S_ISLNK(VFS_I(ip)->i_mode))
1092 		return xfs_bmap_local_to_extents(tp, ip, firstblock, 1,
1093 						 flags, XFS_DATA_FORK,
1094 						 xfs_symlink_local_to_remote);
1095 
1096 	/* should only be called for types that support local format data */
1097 	ASSERT(0);
1098 	return -EFSCORRUPTED;
1099 }
1100 
1101 /*
1102  * Convert inode from non-attributed to attributed.
1103  * Must not be in a transaction, ip must not be locked.
1104  */
1105 int						/* error code */
1106 xfs_bmap_add_attrfork(
1107 	xfs_inode_t		*ip,		/* incore inode pointer */
1108 	int			size,		/* space new attribute needs */
1109 	int			rsvd)		/* xact may use reserved blks */
1110 {
1111 	xfs_fsblock_t		firstblock;	/* 1st block/ag allocated */
1112 	struct xfs_defer_ops	dfops;		/* freed extent records */
1113 	xfs_mount_t		*mp;		/* mount structure */
1114 	xfs_trans_t		*tp;		/* transaction pointer */
1115 	int			blks;		/* space reservation */
1116 	int			version = 1;	/* superblock attr version */
1117 	int			logflags;	/* logging flags */
1118 	int			error;		/* error return value */
1119 
1120 	ASSERT(XFS_IFORK_Q(ip) == 0);
1121 
1122 	mp = ip->i_mount;
1123 	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1124 
1125 	blks = XFS_ADDAFORK_SPACE_RES(mp);
1126 
1127 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_addafork, blks, 0,
1128 			rsvd ? XFS_TRANS_RESERVE : 0, &tp);
1129 	if (error)
1130 		return error;
1131 
1132 	xfs_ilock(ip, XFS_ILOCK_EXCL);
1133 	error = xfs_trans_reserve_quota_nblks(tp, ip, blks, 0, rsvd ?
1134 			XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
1135 			XFS_QMOPT_RES_REGBLKS);
1136 	if (error)
1137 		goto trans_cancel;
1138 	if (XFS_IFORK_Q(ip))
1139 		goto trans_cancel;
1140 	if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS) {
1141 		/*
1142 		 * For inodes coming from pre-6.2 filesystems.
1143 		 */
1144 		ASSERT(ip->i_d.di_aformat == 0);
1145 		ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
1146 	}
1147 	ASSERT(ip->i_d.di_anextents == 0);
1148 
1149 	xfs_trans_ijoin(tp, ip, 0);
1150 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1151 
1152 	switch (ip->i_d.di_format) {
1153 	case XFS_DINODE_FMT_DEV:
1154 		ip->i_d.di_forkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
1155 		break;
1156 	case XFS_DINODE_FMT_UUID:
1157 		ip->i_d.di_forkoff = roundup(sizeof(uuid_t), 8) >> 3;
1158 		break;
1159 	case XFS_DINODE_FMT_LOCAL:
1160 	case XFS_DINODE_FMT_EXTENTS:
1161 	case XFS_DINODE_FMT_BTREE:
1162 		ip->i_d.di_forkoff = xfs_attr_shortform_bytesfit(ip, size);
1163 		if (!ip->i_d.di_forkoff)
1164 			ip->i_d.di_forkoff = xfs_default_attroffset(ip) >> 3;
1165 		else if (mp->m_flags & XFS_MOUNT_ATTR2)
1166 			version = 2;
1167 		break;
1168 	default:
1169 		ASSERT(0);
1170 		error = -EINVAL;
1171 		goto trans_cancel;
1172 	}
1173 
1174 	ASSERT(ip->i_afp == NULL);
1175 	ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP);
1176 	ip->i_afp->if_flags = XFS_IFEXTENTS;
1177 	logflags = 0;
1178 	xfs_defer_init(&dfops, &firstblock);
1179 	switch (ip->i_d.di_format) {
1180 	case XFS_DINODE_FMT_LOCAL:
1181 		error = xfs_bmap_add_attrfork_local(tp, ip, &firstblock, &dfops,
1182 			&logflags);
1183 		break;
1184 	case XFS_DINODE_FMT_EXTENTS:
1185 		error = xfs_bmap_add_attrfork_extents(tp, ip, &firstblock,
1186 			&dfops, &logflags);
1187 		break;
1188 	case XFS_DINODE_FMT_BTREE:
1189 		error = xfs_bmap_add_attrfork_btree(tp, ip, &firstblock, &dfops,
1190 			&logflags);
1191 		break;
1192 	default:
1193 		error = 0;
1194 		break;
1195 	}
1196 	if (logflags)
1197 		xfs_trans_log_inode(tp, ip, logflags);
1198 	if (error)
1199 		goto bmap_cancel;
1200 	if (!xfs_sb_version_hasattr(&mp->m_sb) ||
1201 	   (!xfs_sb_version_hasattr2(&mp->m_sb) && version == 2)) {
1202 		bool log_sb = false;
1203 
1204 		spin_lock(&mp->m_sb_lock);
1205 		if (!xfs_sb_version_hasattr(&mp->m_sb)) {
1206 			xfs_sb_version_addattr(&mp->m_sb);
1207 			log_sb = true;
1208 		}
1209 		if (!xfs_sb_version_hasattr2(&mp->m_sb) && version == 2) {
1210 			xfs_sb_version_addattr2(&mp->m_sb);
1211 			log_sb = true;
1212 		}
1213 		spin_unlock(&mp->m_sb_lock);
1214 		if (log_sb)
1215 			xfs_log_sb(tp);
1216 	}
1217 
1218 	error = xfs_defer_finish(&tp, &dfops, NULL);
1219 	if (error)
1220 		goto bmap_cancel;
1221 	error = xfs_trans_commit(tp);
1222 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1223 	return error;
1224 
1225 bmap_cancel:
1226 	xfs_defer_cancel(&dfops);
1227 trans_cancel:
1228 	xfs_trans_cancel(tp);
1229 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1230 	return error;
1231 }
1232 
1233 /*
1234  * Internal and external extent tree search functions.
1235  */
1236 
1237 /*
1238  * Read in the extents to if_extents.
1239  * All inode fields are set up by caller, we just traverse the btree
1240  * and copy the records in. If the file system cannot contain unwritten
1241  * extents, the records are checked for no "state" flags.
1242  */
1243 int					/* error */
1244 xfs_bmap_read_extents(
1245 	xfs_trans_t		*tp,	/* transaction pointer */
1246 	xfs_inode_t		*ip,	/* incore inode */
1247 	int			whichfork) /* data or attr fork */
1248 {
1249 	struct xfs_btree_block	*block;	/* current btree block */
1250 	xfs_fsblock_t		bno;	/* block # of "block" */
1251 	xfs_buf_t		*bp;	/* buffer for "block" */
1252 	int			error;	/* error return value */
1253 	xfs_exntfmt_t		exntf;	/* XFS_EXTFMT_NOSTATE, if checking */
1254 	xfs_extnum_t		i, j;	/* index into the extents list */
1255 	xfs_ifork_t		*ifp;	/* fork structure */
1256 	int			level;	/* btree level, for checking */
1257 	xfs_mount_t		*mp;	/* file system mount structure */
1258 	__be64			*pp;	/* pointer to block address */
1259 	/* REFERENCED */
1260 	xfs_extnum_t		room;	/* number of entries there's room for */
1261 
1262 	bno = NULLFSBLOCK;
1263 	mp = ip->i_mount;
1264 	ifp = XFS_IFORK_PTR(ip, whichfork);
1265 	exntf = (whichfork != XFS_DATA_FORK) ? XFS_EXTFMT_NOSTATE :
1266 					XFS_EXTFMT_INODE(ip);
1267 	block = ifp->if_broot;
1268 	/*
1269 	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
1270 	 */
1271 	level = be16_to_cpu(block->bb_level);
1272 	ASSERT(level > 0);
1273 	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
1274 	bno = be64_to_cpu(*pp);
1275 	ASSERT(bno != NULLFSBLOCK);
1276 	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
1277 	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
1278 	/*
1279 	 * Go down the tree until leaf level is reached, following the first
1280 	 * pointer (leftmost) at each level.
1281 	 */
1282 	while (level-- > 0) {
1283 		error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
1284 				XFS_BMAP_BTREE_REF, &xfs_bmbt_buf_ops);
1285 		if (error)
1286 			return error;
1287 		block = XFS_BUF_TO_BLOCK(bp);
1288 		if (level == 0)
1289 			break;
1290 		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
1291 		bno = be64_to_cpu(*pp);
1292 		XFS_WANT_CORRUPTED_GOTO(mp,
1293 			XFS_FSB_SANITY_CHECK(mp, bno), error0);
1294 		xfs_trans_brelse(tp, bp);
1295 	}
1296 	/*
1297 	 * Here with bp and block set to the leftmost leaf node in the tree.
1298 	 */
1299 	room = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
1300 	i = 0;
1301 	/*
1302 	 * Loop over all leaf nodes.  Copy information to the extent records.
1303 	 */
1304 	for (;;) {
1305 		xfs_bmbt_rec_t	*frp;
1306 		xfs_fsblock_t	nextbno;
1307 		xfs_extnum_t	num_recs;
1308 		xfs_extnum_t	start;
1309 
1310 		num_recs = xfs_btree_get_numrecs(block);
1311 		if (unlikely(i + num_recs > room)) {
1312 			ASSERT(i + num_recs <= room);
1313 			xfs_warn(ip->i_mount,
1314 				"corrupt dinode %Lu, (btree extents).",
1315 				(unsigned long long) ip->i_ino);
1316 			XFS_CORRUPTION_ERROR("xfs_bmap_read_extents(1)",
1317 				XFS_ERRLEVEL_LOW, ip->i_mount, block);
1318 			goto error0;
1319 		}
1320 		/*
1321 		 * Read-ahead the next leaf block, if any.
1322 		 */
1323 		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
1324 		if (nextbno != NULLFSBLOCK)
1325 			xfs_btree_reada_bufl(mp, nextbno, 1,
1326 					     &xfs_bmbt_buf_ops);
1327 		/*
1328 		 * Copy records into the extent records.
1329 		 */
1330 		frp = XFS_BMBT_REC_ADDR(mp, block, 1);
1331 		start = i;
1332 		for (j = 0; j < num_recs; j++, i++, frp++) {
1333 			xfs_bmbt_rec_host_t *trp = xfs_iext_get_ext(ifp, i);
1334 			trp->l0 = be64_to_cpu(frp->l0);
1335 			trp->l1 = be64_to_cpu(frp->l1);
1336 		}
1337 		if (exntf == XFS_EXTFMT_NOSTATE) {
1338 			/*
1339 			 * Check all attribute bmap btree records and
1340 			 * any "older" data bmap btree records for a
1341 			 * set bit in the "extent flag" position.
1342 			 */
1343 			if (unlikely(xfs_check_nostate_extents(ifp,
1344 					start, num_recs))) {
1345 				XFS_ERROR_REPORT("xfs_bmap_read_extents(2)",
1346 						 XFS_ERRLEVEL_LOW,
1347 						 ip->i_mount);
1348 				goto error0;
1349 			}
1350 		}
1351 		xfs_trans_brelse(tp, bp);
1352 		bno = nextbno;
1353 		/*
1354 		 * If we've reached the end, stop.
1355 		 */
1356 		if (bno == NULLFSBLOCK)
1357 			break;
1358 		error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
1359 				XFS_BMAP_BTREE_REF, &xfs_bmbt_buf_ops);
1360 		if (error)
1361 			return error;
1362 		block = XFS_BUF_TO_BLOCK(bp);
1363 	}
1364 	ASSERT(i == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
1365 	ASSERT(i == XFS_IFORK_NEXTENTS(ip, whichfork));
1366 	XFS_BMAP_TRACE_EXLIST(ip, i, whichfork);
1367 	return 0;
1368 error0:
1369 	xfs_trans_brelse(tp, bp);
1370 	return -EFSCORRUPTED;
1371 }
1372 
1373 
1374 /*
1375  * Search the extent records for the entry containing block bno.
1376  * If bno lies in a hole, point to the next entry.  If bno lies
1377  * past eof, *eofp will be set, and *prevp will contain the last
1378  * entry (null if none).  Else, *lastxp will be set to the index
1379  * of the found entry; *gotp will contain the entry.
1380  */
1381 STATIC xfs_bmbt_rec_host_t *		/* pointer to found extent entry */
1382 xfs_bmap_search_multi_extents(
1383 	xfs_ifork_t	*ifp,		/* inode fork pointer */
1384 	xfs_fileoff_t	bno,		/* block number searched for */
1385 	int		*eofp,		/* out: end of file found */
1386 	xfs_extnum_t	*lastxp,	/* out: last extent index */
1387 	xfs_bmbt_irec_t	*gotp,		/* out: extent entry found */
1388 	xfs_bmbt_irec_t	*prevp)		/* out: previous extent entry found */
1389 {
1390 	xfs_bmbt_rec_host_t *ep;		/* extent record pointer */
1391 	xfs_extnum_t	lastx;		/* last extent index */
1392 
1393 	/*
1394 	 * Initialize the extent entry structure to catch access to
1395 	 * uninitialized br_startblock field.
1396 	 */
1397 	gotp->br_startoff = 0xffa5a5a5a5a5a5a5LL;
1398 	gotp->br_blockcount = 0xa55a5a5a5a5a5a5aLL;
1399 	gotp->br_state = XFS_EXT_INVALID;
1400 	gotp->br_startblock = 0xffffa5a5a5a5a5a5LL;
1401 	prevp->br_startoff = NULLFILEOFF;
1402 
1403 	ep = xfs_iext_bno_to_ext(ifp, bno, &lastx);
1404 	if (lastx > 0) {
1405 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx - 1), prevp);
1406 	}
1407 	if (lastx < (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))) {
1408 		xfs_bmbt_get_all(ep, gotp);
1409 		*eofp = 0;
1410 	} else {
1411 		if (lastx > 0) {
1412 			*gotp = *prevp;
1413 		}
1414 		*eofp = 1;
1415 		ep = NULL;
1416 	}
1417 	*lastxp = lastx;
1418 	return ep;
1419 }
1420 
1421 /*
1422  * Search the extents list for the inode, for the extent containing bno.
1423  * If bno lies in a hole, point to the next entry.  If bno lies past eof,
1424  * *eofp will be set, and *prevp will contain the last entry (null if none).
1425  * Else, *lastxp will be set to the index of the found
1426  * entry; *gotp will contain the entry.
1427  */
1428 xfs_bmbt_rec_host_t *                 /* pointer to found extent entry */
1429 xfs_bmap_search_extents(
1430 	xfs_inode_t     *ip,            /* incore inode pointer */
1431 	xfs_fileoff_t   bno,            /* block number searched for */
1432 	int             fork,      	/* data or attr fork */
1433 	int             *eofp,          /* out: end of file found */
1434 	xfs_extnum_t    *lastxp,        /* out: last extent index */
1435 	xfs_bmbt_irec_t *gotp,          /* out: extent entry found */
1436 	xfs_bmbt_irec_t *prevp)         /* out: previous extent entry found */
1437 {
1438 	xfs_ifork_t	*ifp;		/* inode fork pointer */
1439 	xfs_bmbt_rec_host_t  *ep;            /* extent record pointer */
1440 
1441 	XFS_STATS_INC(ip->i_mount, xs_look_exlist);
1442 	ifp = XFS_IFORK_PTR(ip, fork);
1443 
1444 	ep = xfs_bmap_search_multi_extents(ifp, bno, eofp, lastxp, gotp, prevp);
1445 
1446 	if (unlikely(!(gotp->br_startblock) && (*lastxp != NULLEXTNUM) &&
1447 		     !(XFS_IS_REALTIME_INODE(ip) && fork == XFS_DATA_FORK))) {
1448 		xfs_alert_tag(ip->i_mount, XFS_PTAG_FSBLOCK_ZERO,
1449 				"Access to block zero in inode %llu "
1450 				"start_block: %llx start_off: %llx "
1451 				"blkcnt: %llx extent-state: %x lastx: %x",
1452 			(unsigned long long)ip->i_ino,
1453 			(unsigned long long)gotp->br_startblock,
1454 			(unsigned long long)gotp->br_startoff,
1455 			(unsigned long long)gotp->br_blockcount,
1456 			gotp->br_state, *lastxp);
1457 		*lastxp = NULLEXTNUM;
1458 		*eofp = 1;
1459 		return NULL;
1460 	}
1461 	return ep;
1462 }
1463 
1464 /*
1465  * Returns the file-relative block number of the first unused block(s)
1466  * in the file with at least "len" logically contiguous blocks free.
1467  * This is the lowest-address hole if the file has holes, else the first block
1468  * past the end of file.
1469  * Return 0 if the file is currently local (in-inode).
1470  */
1471 int						/* error */
1472 xfs_bmap_first_unused(
1473 	xfs_trans_t	*tp,			/* transaction pointer */
1474 	xfs_inode_t	*ip,			/* incore inode */
1475 	xfs_extlen_t	len,			/* size of hole to find */
1476 	xfs_fileoff_t	*first_unused,		/* unused block */
1477 	int		whichfork)		/* data or attr fork */
1478 {
1479 	int		error;			/* error return value */
1480 	int		idx;			/* extent record index */
1481 	xfs_ifork_t	*ifp;			/* inode fork pointer */
1482 	xfs_fileoff_t	lastaddr;		/* last block number seen */
1483 	xfs_fileoff_t	lowest;			/* lowest useful block */
1484 	xfs_fileoff_t	max;			/* starting useful block */
1485 	xfs_fileoff_t	off;			/* offset for this block */
1486 	xfs_extnum_t	nextents;		/* number of extent entries */
1487 
1488 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE ||
1489 	       XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ||
1490 	       XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
1491 	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
1492 		*first_unused = 0;
1493 		return 0;
1494 	}
1495 	ifp = XFS_IFORK_PTR(ip, whichfork);
1496 	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
1497 	    (error = xfs_iread_extents(tp, ip, whichfork)))
1498 		return error;
1499 	lowest = *first_unused;
1500 	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
1501 	for (idx = 0, lastaddr = 0, max = lowest; idx < nextents; idx++) {
1502 		xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, idx);
1503 		off = xfs_bmbt_get_startoff(ep);
1504 		/*
1505 		 * See if the hole before this extent will work.
1506 		 */
1507 		if (off >= lowest + len && off - max >= len) {
1508 			*first_unused = max;
1509 			return 0;
1510 		}
1511 		lastaddr = off + xfs_bmbt_get_blockcount(ep);
1512 		max = XFS_FILEOFF_MAX(lastaddr, lowest);
1513 	}
1514 	*first_unused = max;
1515 	return 0;
1516 }
1517 
1518 /*
1519  * Returns the file-relative block number of the last block - 1 before
1520  * last_block (input value) in the file.
1521  * This is not based on i_size, it is based on the extent records.
1522  * Returns 0 for local files, as they do not have extent records.
1523  */
1524 int						/* error */
1525 xfs_bmap_last_before(
1526 	xfs_trans_t	*tp,			/* transaction pointer */
1527 	xfs_inode_t	*ip,			/* incore inode */
1528 	xfs_fileoff_t	*last_block,		/* last block */
1529 	int		whichfork)		/* data or attr fork */
1530 {
1531 	xfs_fileoff_t	bno;			/* input file offset */
1532 	int		eof;			/* hit end of file */
1533 	xfs_bmbt_rec_host_t *ep;		/* pointer to last extent */
1534 	int		error;			/* error return value */
1535 	xfs_bmbt_irec_t	got;			/* current extent value */
1536 	xfs_ifork_t	*ifp;			/* inode fork pointer */
1537 	xfs_extnum_t	lastx;			/* last extent used */
1538 	xfs_bmbt_irec_t	prev;			/* previous extent value */
1539 
1540 	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
1541 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
1542 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
1543 	       return -EIO;
1544 	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
1545 		*last_block = 0;
1546 		return 0;
1547 	}
1548 	ifp = XFS_IFORK_PTR(ip, whichfork);
1549 	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
1550 	    (error = xfs_iread_extents(tp, ip, whichfork)))
1551 		return error;
1552 	bno = *last_block - 1;
1553 	ep = xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
1554 		&prev);
1555 	if (eof || xfs_bmbt_get_startoff(ep) > bno) {
1556 		if (prev.br_startoff == NULLFILEOFF)
1557 			*last_block = 0;
1558 		else
1559 			*last_block = prev.br_startoff + prev.br_blockcount;
1560 	}
1561 	/*
1562 	 * Otherwise *last_block is already the right answer.
1563 	 */
1564 	return 0;
1565 }
1566 
1567 int
1568 xfs_bmap_last_extent(
1569 	struct xfs_trans	*tp,
1570 	struct xfs_inode	*ip,
1571 	int			whichfork,
1572 	struct xfs_bmbt_irec	*rec,
1573 	int			*is_empty)
1574 {
1575 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
1576 	int			error;
1577 	int			nextents;
1578 
1579 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
1580 		error = xfs_iread_extents(tp, ip, whichfork);
1581 		if (error)
1582 			return error;
1583 	}
1584 
1585 	nextents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
1586 	if (nextents == 0) {
1587 		*is_empty = 1;
1588 		return 0;
1589 	}
1590 
1591 	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, nextents - 1), rec);
1592 	*is_empty = 0;
1593 	return 0;
1594 }
1595 
1596 /*
1597  * Check the last inode extent to determine whether this allocation will result
1598  * in blocks being allocated at the end of the file. When we allocate new data
1599  * blocks at the end of the file which do not start at the previous data block,
1600  * we will try to align the new blocks at stripe unit boundaries.
1601  *
1602  * Returns 1 in bma->aeof if the file (fork) is empty as any new write will be
1603  * at, or past the EOF.
1604  */
1605 STATIC int
1606 xfs_bmap_isaeof(
1607 	struct xfs_bmalloca	*bma,
1608 	int			whichfork)
1609 {
1610 	struct xfs_bmbt_irec	rec;
1611 	int			is_empty;
1612 	int			error;
1613 
1614 	bma->aeof = 0;
1615 	error = xfs_bmap_last_extent(NULL, bma->ip, whichfork, &rec,
1616 				     &is_empty);
1617 	if (error)
1618 		return error;
1619 
1620 	if (is_empty) {
1621 		bma->aeof = 1;
1622 		return 0;
1623 	}
1624 
1625 	/*
1626 	 * Check if we are allocation or past the last extent, or at least into
1627 	 * the last delayed allocated extent.
1628 	 */
1629 	bma->aeof = bma->offset >= rec.br_startoff + rec.br_blockcount ||
1630 		(bma->offset >= rec.br_startoff &&
1631 		 isnullstartblock(rec.br_startblock));
1632 	return 0;
1633 }
1634 
1635 /*
1636  * Returns the file-relative block number of the first block past eof in
1637  * the file.  This is not based on i_size, it is based on the extent records.
1638  * Returns 0 for local files, as they do not have extent records.
1639  */
1640 int
1641 xfs_bmap_last_offset(
1642 	struct xfs_inode	*ip,
1643 	xfs_fileoff_t		*last_block,
1644 	int			whichfork)
1645 {
1646 	struct xfs_bmbt_irec	rec;
1647 	int			is_empty;
1648 	int			error;
1649 
1650 	*last_block = 0;
1651 
1652 	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL)
1653 		return 0;
1654 
1655 	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
1656 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
1657 	       return -EIO;
1658 
1659 	error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, &is_empty);
1660 	if (error || is_empty)
1661 		return error;
1662 
1663 	*last_block = rec.br_startoff + rec.br_blockcount;
1664 	return 0;
1665 }
1666 
1667 /*
1668  * Returns whether the selected fork of the inode has exactly one
1669  * block or not.  For the data fork we check this matches di_size,
1670  * implying the file's range is 0..bsize-1.
1671  */
1672 int					/* 1=>1 block, 0=>otherwise */
1673 xfs_bmap_one_block(
1674 	xfs_inode_t	*ip,		/* incore inode */
1675 	int		whichfork)	/* data or attr fork */
1676 {
1677 	xfs_bmbt_rec_host_t *ep;	/* ptr to fork's extent */
1678 	xfs_ifork_t	*ifp;		/* inode fork pointer */
1679 	int		rval;		/* return value */
1680 	xfs_bmbt_irec_t	s;		/* internal version of extent */
1681 
1682 #ifndef DEBUG
1683 	if (whichfork == XFS_DATA_FORK)
1684 		return XFS_ISIZE(ip) == ip->i_mount->m_sb.sb_blocksize;
1685 #endif	/* !DEBUG */
1686 	if (XFS_IFORK_NEXTENTS(ip, whichfork) != 1)
1687 		return 0;
1688 	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
1689 		return 0;
1690 	ifp = XFS_IFORK_PTR(ip, whichfork);
1691 	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
1692 	ep = xfs_iext_get_ext(ifp, 0);
1693 	xfs_bmbt_get_all(ep, &s);
1694 	rval = s.br_startoff == 0 && s.br_blockcount == 1;
1695 	if (rval && whichfork == XFS_DATA_FORK)
1696 		ASSERT(XFS_ISIZE(ip) == ip->i_mount->m_sb.sb_blocksize);
1697 	return rval;
1698 }
1699 
1700 /*
1701  * Extent tree manipulation functions used during allocation.
1702  */
1703 
1704 /*
1705  * Convert a delayed allocation to a real allocation.
1706  */
1707 STATIC int				/* error */
1708 xfs_bmap_add_extent_delay_real(
1709 	struct xfs_bmalloca	*bma,
1710 	int			whichfork)
1711 {
1712 	struct xfs_bmbt_irec	*new = &bma->got;
1713 	int			diff;	/* temp value */
1714 	xfs_bmbt_rec_host_t	*ep;	/* extent entry for idx */
1715 	int			error;	/* error return value */
1716 	int			i;	/* temp state */
1717 	xfs_ifork_t		*ifp;	/* inode fork pointer */
1718 	xfs_fileoff_t		new_endoff;	/* end offset of new entry */
1719 	xfs_bmbt_irec_t		r[3];	/* neighbor extent entries */
1720 					/* left is 0, right is 1, prev is 2 */
1721 	int			rval=0;	/* return value (logging flags) */
1722 	int			state = 0;/* state bits, accessed thru macros */
1723 	xfs_filblks_t		da_new; /* new count del alloc blocks used */
1724 	xfs_filblks_t		da_old; /* old count del alloc blocks used */
1725 	xfs_filblks_t		temp=0;	/* value for da_new calculations */
1726 	xfs_filblks_t		temp2=0;/* value for da_new calculations */
1727 	int			tmp_rval;	/* partial logging flags */
1728 	struct xfs_mount	*mp;
1729 	xfs_extnum_t		*nextents;
1730 
1731 	mp = bma->ip->i_mount;
1732 	ifp = XFS_IFORK_PTR(bma->ip, whichfork);
1733 	ASSERT(whichfork != XFS_ATTR_FORK);
1734 	nextents = (whichfork == XFS_COW_FORK ? &bma->ip->i_cnextents :
1735 						&bma->ip->i_d.di_nextents);
1736 
1737 	ASSERT(bma->idx >= 0);
1738 	ASSERT(bma->idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
1739 	ASSERT(!isnullstartblock(new->br_startblock));
1740 	ASSERT(!bma->cur ||
1741 	       (bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
1742 
1743 	XFS_STATS_INC(mp, xs_add_exlist);
1744 
1745 #define	LEFT		r[0]
1746 #define	RIGHT		r[1]
1747 #define	PREV		r[2]
1748 
1749 	if (whichfork == XFS_COW_FORK)
1750 		state |= BMAP_COWFORK;
1751 
1752 	/*
1753 	 * Set up a bunch of variables to make the tests simpler.
1754 	 */
1755 	ep = xfs_iext_get_ext(ifp, bma->idx);
1756 	xfs_bmbt_get_all(ep, &PREV);
1757 	new_endoff = new->br_startoff + new->br_blockcount;
1758 	ASSERT(PREV.br_startoff <= new->br_startoff);
1759 	ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
1760 
1761 	da_old = startblockval(PREV.br_startblock);
1762 	da_new = 0;
1763 
1764 	/*
1765 	 * Set flags determining what part of the previous delayed allocation
1766 	 * extent is being replaced by a real allocation.
1767 	 */
1768 	if (PREV.br_startoff == new->br_startoff)
1769 		state |= BMAP_LEFT_FILLING;
1770 	if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
1771 		state |= BMAP_RIGHT_FILLING;
1772 
1773 	/*
1774 	 * Check and set flags if this segment has a left neighbor.
1775 	 * Don't set contiguous if the combined extent would be too large.
1776 	 */
1777 	if (bma->idx > 0) {
1778 		state |= BMAP_LEFT_VALID;
1779 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx - 1), &LEFT);
1780 
1781 		if (isnullstartblock(LEFT.br_startblock))
1782 			state |= BMAP_LEFT_DELAY;
1783 	}
1784 
1785 	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
1786 	    LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
1787 	    LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
1788 	    LEFT.br_state == new->br_state &&
1789 	    LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
1790 		state |= BMAP_LEFT_CONTIG;
1791 
1792 	/*
1793 	 * Check and set flags if this segment has a right neighbor.
1794 	 * Don't set contiguous if the combined extent would be too large.
1795 	 * Also check for all-three-contiguous being too large.
1796 	 */
1797 	if (bma->idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
1798 		state |= BMAP_RIGHT_VALID;
1799 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx + 1), &RIGHT);
1800 
1801 		if (isnullstartblock(RIGHT.br_startblock))
1802 			state |= BMAP_RIGHT_DELAY;
1803 	}
1804 
1805 	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
1806 	    new_endoff == RIGHT.br_startoff &&
1807 	    new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
1808 	    new->br_state == RIGHT.br_state &&
1809 	    new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
1810 	    ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1811 		       BMAP_RIGHT_FILLING)) !=
1812 		      (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1813 		       BMAP_RIGHT_FILLING) ||
1814 	     LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
1815 			<= MAXEXTLEN))
1816 		state |= BMAP_RIGHT_CONTIG;
1817 
1818 	error = 0;
1819 	/*
1820 	 * Switch out based on the FILLING and CONTIG state bits.
1821 	 */
1822 	switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1823 			 BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
1824 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1825 	     BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1826 		/*
1827 		 * Filling in all of a previously delayed allocation extent.
1828 		 * The left and right neighbors are both contiguous with new.
1829 		 */
1830 		bma->idx--;
1831 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
1832 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
1833 			LEFT.br_blockcount + PREV.br_blockcount +
1834 			RIGHT.br_blockcount);
1835 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
1836 
1837 		xfs_iext_remove(bma->ip, bma->idx + 1, 2, state);
1838 		(*nextents)--;
1839 		if (bma->cur == NULL)
1840 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1841 		else {
1842 			rval = XFS_ILOG_CORE;
1843 			error = xfs_bmbt_lookup_eq(bma->cur, RIGHT.br_startoff,
1844 					RIGHT.br_startblock,
1845 					RIGHT.br_blockcount, &i);
1846 			if (error)
1847 				goto done;
1848 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1849 			error = xfs_btree_delete(bma->cur, &i);
1850 			if (error)
1851 				goto done;
1852 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1853 			error = xfs_btree_decrement(bma->cur, 0, &i);
1854 			if (error)
1855 				goto done;
1856 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1857 			error = xfs_bmbt_update(bma->cur, LEFT.br_startoff,
1858 					LEFT.br_startblock,
1859 					LEFT.br_blockcount +
1860 					PREV.br_blockcount +
1861 					RIGHT.br_blockcount, LEFT.br_state);
1862 			if (error)
1863 				goto done;
1864 		}
1865 		break;
1866 
1867 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1868 		/*
1869 		 * Filling in all of a previously delayed allocation extent.
1870 		 * The left neighbor is contiguous, the right is not.
1871 		 */
1872 		bma->idx--;
1873 
1874 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
1875 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
1876 			LEFT.br_blockcount + PREV.br_blockcount);
1877 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
1878 
1879 		xfs_iext_remove(bma->ip, bma->idx + 1, 1, state);
1880 		if (bma->cur == NULL)
1881 			rval = XFS_ILOG_DEXT;
1882 		else {
1883 			rval = 0;
1884 			error = xfs_bmbt_lookup_eq(bma->cur, LEFT.br_startoff,
1885 					LEFT.br_startblock, LEFT.br_blockcount,
1886 					&i);
1887 			if (error)
1888 				goto done;
1889 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1890 			error = xfs_bmbt_update(bma->cur, LEFT.br_startoff,
1891 					LEFT.br_startblock,
1892 					LEFT.br_blockcount +
1893 					PREV.br_blockcount, LEFT.br_state);
1894 			if (error)
1895 				goto done;
1896 		}
1897 		break;
1898 
1899 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1900 		/*
1901 		 * Filling in all of a previously delayed allocation extent.
1902 		 * The right neighbor is contiguous, the left is not.
1903 		 */
1904 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
1905 		xfs_bmbt_set_startblock(ep, new->br_startblock);
1906 		xfs_bmbt_set_blockcount(ep,
1907 			PREV.br_blockcount + RIGHT.br_blockcount);
1908 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
1909 
1910 		xfs_iext_remove(bma->ip, bma->idx + 1, 1, state);
1911 		if (bma->cur == NULL)
1912 			rval = XFS_ILOG_DEXT;
1913 		else {
1914 			rval = 0;
1915 			error = xfs_bmbt_lookup_eq(bma->cur, RIGHT.br_startoff,
1916 					RIGHT.br_startblock,
1917 					RIGHT.br_blockcount, &i);
1918 			if (error)
1919 				goto done;
1920 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1921 			error = xfs_bmbt_update(bma->cur, PREV.br_startoff,
1922 					new->br_startblock,
1923 					PREV.br_blockcount +
1924 					RIGHT.br_blockcount, PREV.br_state);
1925 			if (error)
1926 				goto done;
1927 		}
1928 		break;
1929 
1930 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
1931 		/*
1932 		 * Filling in all of a previously delayed allocation extent.
1933 		 * Neither the left nor right neighbors are contiguous with
1934 		 * the new one.
1935 		 */
1936 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
1937 		xfs_bmbt_set_startblock(ep, new->br_startblock);
1938 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
1939 
1940 		(*nextents)++;
1941 		if (bma->cur == NULL)
1942 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1943 		else {
1944 			rval = XFS_ILOG_CORE;
1945 			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
1946 					new->br_startblock, new->br_blockcount,
1947 					&i);
1948 			if (error)
1949 				goto done;
1950 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
1951 			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
1952 			error = xfs_btree_insert(bma->cur, &i);
1953 			if (error)
1954 				goto done;
1955 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1956 		}
1957 		break;
1958 
1959 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
1960 		/*
1961 		 * Filling in the first part of a previous delayed allocation.
1962 		 * The left neighbor is contiguous.
1963 		 */
1964 		trace_xfs_bmap_pre_update(bma->ip, bma->idx - 1, state, _THIS_IP_);
1965 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx - 1),
1966 			LEFT.br_blockcount + new->br_blockcount);
1967 		xfs_bmbt_set_startoff(ep,
1968 			PREV.br_startoff + new->br_blockcount);
1969 		trace_xfs_bmap_post_update(bma->ip, bma->idx - 1, state, _THIS_IP_);
1970 
1971 		temp = PREV.br_blockcount - new->br_blockcount;
1972 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
1973 		xfs_bmbt_set_blockcount(ep, temp);
1974 		if (bma->cur == NULL)
1975 			rval = XFS_ILOG_DEXT;
1976 		else {
1977 			rval = 0;
1978 			error = xfs_bmbt_lookup_eq(bma->cur, LEFT.br_startoff,
1979 					LEFT.br_startblock, LEFT.br_blockcount,
1980 					&i);
1981 			if (error)
1982 				goto done;
1983 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1984 			error = xfs_bmbt_update(bma->cur, LEFT.br_startoff,
1985 					LEFT.br_startblock,
1986 					LEFT.br_blockcount +
1987 					new->br_blockcount,
1988 					LEFT.br_state);
1989 			if (error)
1990 				goto done;
1991 		}
1992 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1993 			startblockval(PREV.br_startblock));
1994 		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
1995 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
1996 
1997 		bma->idx--;
1998 		break;
1999 
2000 	case BMAP_LEFT_FILLING:
2001 		/*
2002 		 * Filling in the first part of a previous delayed allocation.
2003 		 * The left neighbor is not contiguous.
2004 		 */
2005 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
2006 		xfs_bmbt_set_startoff(ep, new_endoff);
2007 		temp = PREV.br_blockcount - new->br_blockcount;
2008 		xfs_bmbt_set_blockcount(ep, temp);
2009 		xfs_iext_insert(bma->ip, bma->idx, 1, new, state);
2010 		(*nextents)++;
2011 		if (bma->cur == NULL)
2012 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2013 		else {
2014 			rval = XFS_ILOG_CORE;
2015 			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
2016 					new->br_startblock, new->br_blockcount,
2017 					&i);
2018 			if (error)
2019 				goto done;
2020 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2021 			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
2022 			error = xfs_btree_insert(bma->cur, &i);
2023 			if (error)
2024 				goto done;
2025 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2026 		}
2027 
2028 		if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
2029 			error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
2030 					bma->firstblock, bma->dfops,
2031 					&bma->cur, 1, &tmp_rval, whichfork);
2032 			rval |= tmp_rval;
2033 			if (error)
2034 				goto done;
2035 		}
2036 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
2037 			startblockval(PREV.br_startblock) -
2038 			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
2039 		ep = xfs_iext_get_ext(ifp, bma->idx + 1);
2040 		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
2041 		trace_xfs_bmap_post_update(bma->ip, bma->idx + 1, state, _THIS_IP_);
2042 		break;
2043 
2044 	case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2045 		/*
2046 		 * Filling in the last part of a previous delayed allocation.
2047 		 * The right neighbor is contiguous with the new allocation.
2048 		 */
2049 		temp = PREV.br_blockcount - new->br_blockcount;
2050 		trace_xfs_bmap_pre_update(bma->ip, bma->idx + 1, state, _THIS_IP_);
2051 		xfs_bmbt_set_blockcount(ep, temp);
2052 		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, bma->idx + 1),
2053 			new->br_startoff, new->br_startblock,
2054 			new->br_blockcount + RIGHT.br_blockcount,
2055 			RIGHT.br_state);
2056 		trace_xfs_bmap_post_update(bma->ip, bma->idx + 1, state, _THIS_IP_);
2057 		if (bma->cur == NULL)
2058 			rval = XFS_ILOG_DEXT;
2059 		else {
2060 			rval = 0;
2061 			error = xfs_bmbt_lookup_eq(bma->cur, RIGHT.br_startoff,
2062 					RIGHT.br_startblock,
2063 					RIGHT.br_blockcount, &i);
2064 			if (error)
2065 				goto done;
2066 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2067 			error = xfs_bmbt_update(bma->cur, new->br_startoff,
2068 					new->br_startblock,
2069 					new->br_blockcount +
2070 					RIGHT.br_blockcount,
2071 					RIGHT.br_state);
2072 			if (error)
2073 				goto done;
2074 		}
2075 
2076 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
2077 			startblockval(PREV.br_startblock));
2078 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
2079 		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
2080 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
2081 
2082 		bma->idx++;
2083 		break;
2084 
2085 	case BMAP_RIGHT_FILLING:
2086 		/*
2087 		 * Filling in the last part of a previous delayed allocation.
2088 		 * The right neighbor is not contiguous.
2089 		 */
2090 		temp = PREV.br_blockcount - new->br_blockcount;
2091 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
2092 		xfs_bmbt_set_blockcount(ep, temp);
2093 		xfs_iext_insert(bma->ip, bma->idx + 1, 1, new, state);
2094 		(*nextents)++;
2095 		if (bma->cur == NULL)
2096 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2097 		else {
2098 			rval = XFS_ILOG_CORE;
2099 			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
2100 					new->br_startblock, new->br_blockcount,
2101 					&i);
2102 			if (error)
2103 				goto done;
2104 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2105 			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
2106 			error = xfs_btree_insert(bma->cur, &i);
2107 			if (error)
2108 				goto done;
2109 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2110 		}
2111 
2112 		if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
2113 			error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
2114 				bma->firstblock, bma->dfops, &bma->cur, 1,
2115 				&tmp_rval, whichfork);
2116 			rval |= tmp_rval;
2117 			if (error)
2118 				goto done;
2119 		}
2120 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
2121 			startblockval(PREV.br_startblock) -
2122 			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
2123 		ep = xfs_iext_get_ext(ifp, bma->idx);
2124 		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
2125 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
2126 
2127 		bma->idx++;
2128 		break;
2129 
2130 	case 0:
2131 		/*
2132 		 * Filling in the middle part of a previous delayed allocation.
2133 		 * Contiguity is impossible here.
2134 		 * This case is avoided almost all the time.
2135 		 *
2136 		 * We start with a delayed allocation:
2137 		 *
2138 		 * +ddddddddddddddddddddddddddddddddddddddddddddddddddddddd+
2139 		 *  PREV @ idx
2140 		 *
2141 	         * and we are allocating:
2142 		 *                     +rrrrrrrrrrrrrrrrr+
2143 		 *			      new
2144 		 *
2145 		 * and we set it up for insertion as:
2146 		 * +ddddddddddddddddddd+rrrrrrrrrrrrrrrrr+ddddddddddddddddd+
2147 		 *                            new
2148 		 *  PREV @ idx          LEFT              RIGHT
2149 		 *                      inserted at idx + 1
2150 		 */
2151 		temp = new->br_startoff - PREV.br_startoff;
2152 		temp2 = PREV.br_startoff + PREV.br_blockcount - new_endoff;
2153 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, 0, _THIS_IP_);
2154 		xfs_bmbt_set_blockcount(ep, temp);	/* truncate PREV */
2155 		LEFT = *new;
2156 		RIGHT.br_state = PREV.br_state;
2157 		RIGHT.br_startblock = nullstartblock(
2158 				(int)xfs_bmap_worst_indlen(bma->ip, temp2));
2159 		RIGHT.br_startoff = new_endoff;
2160 		RIGHT.br_blockcount = temp2;
2161 		/* insert LEFT (r[0]) and RIGHT (r[1]) at the same time */
2162 		xfs_iext_insert(bma->ip, bma->idx + 1, 2, &LEFT, state);
2163 		(*nextents)++;
2164 		if (bma->cur == NULL)
2165 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2166 		else {
2167 			rval = XFS_ILOG_CORE;
2168 			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
2169 					new->br_startblock, new->br_blockcount,
2170 					&i);
2171 			if (error)
2172 				goto done;
2173 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2174 			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
2175 			error = xfs_btree_insert(bma->cur, &i);
2176 			if (error)
2177 				goto done;
2178 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2179 		}
2180 
2181 		if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
2182 			error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
2183 					bma->firstblock, bma->dfops, &bma->cur,
2184 					1, &tmp_rval, whichfork);
2185 			rval |= tmp_rval;
2186 			if (error)
2187 				goto done;
2188 		}
2189 		temp = xfs_bmap_worst_indlen(bma->ip, temp);
2190 		temp2 = xfs_bmap_worst_indlen(bma->ip, temp2);
2191 		diff = (int)(temp + temp2 - startblockval(PREV.br_startblock) -
2192 			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
2193 		if (diff > 0) {
2194 			error = xfs_mod_fdblocks(bma->ip->i_mount,
2195 						 -((int64_t)diff), false);
2196 			ASSERT(!error);
2197 			if (error)
2198 				goto done;
2199 		}
2200 
2201 		ep = xfs_iext_get_ext(ifp, bma->idx);
2202 		xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
2203 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
2204 		trace_xfs_bmap_pre_update(bma->ip, bma->idx + 2, state, _THIS_IP_);
2205 		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, bma->idx + 2),
2206 			nullstartblock((int)temp2));
2207 		trace_xfs_bmap_post_update(bma->ip, bma->idx + 2, state, _THIS_IP_);
2208 
2209 		bma->idx++;
2210 		da_new = temp + temp2;
2211 		break;
2212 
2213 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2214 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2215 	case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
2216 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2217 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2218 	case BMAP_LEFT_CONTIG:
2219 	case BMAP_RIGHT_CONTIG:
2220 		/*
2221 		 * These cases are all impossible.
2222 		 */
2223 		ASSERT(0);
2224 	}
2225 
2226 	/* add reverse mapping */
2227 	error = xfs_rmap_map_extent(mp, bma->dfops, bma->ip, whichfork, new);
2228 	if (error)
2229 		goto done;
2230 
2231 	/* convert to a btree if necessary */
2232 	if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
2233 		int	tmp_logflags;	/* partial log flag return val */
2234 
2235 		ASSERT(bma->cur == NULL);
2236 		error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
2237 				bma->firstblock, bma->dfops, &bma->cur,
2238 				da_old > 0, &tmp_logflags, whichfork);
2239 		bma->logflags |= tmp_logflags;
2240 		if (error)
2241 			goto done;
2242 	}
2243 
2244 	/* adjust for changes in reserved delayed indirect blocks */
2245 	if (da_old || da_new) {
2246 		temp = da_new;
2247 		if (bma->cur)
2248 			temp += bma->cur->bc_private.b.allocated;
2249 		ASSERT(temp <= da_old);
2250 		if (temp < da_old)
2251 			xfs_mod_fdblocks(bma->ip->i_mount,
2252 					(int64_t)(da_old - temp), false);
2253 	}
2254 
2255 	/* clear out the allocated field, done with it now in any case. */
2256 	if (bma->cur)
2257 		bma->cur->bc_private.b.allocated = 0;
2258 
2259 	xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
2260 done:
2261 	if (whichfork != XFS_COW_FORK)
2262 		bma->logflags |= rval;
2263 	return error;
2264 #undef	LEFT
2265 #undef	RIGHT
2266 #undef	PREV
2267 }
2268 
2269 /*
2270  * Convert an unwritten allocation to a real allocation or vice versa.
2271  */
2272 STATIC int				/* error */
2273 xfs_bmap_add_extent_unwritten_real(
2274 	struct xfs_trans	*tp,
2275 	xfs_inode_t		*ip,	/* incore inode pointer */
2276 	xfs_extnum_t		*idx,	/* extent number to update/insert */
2277 	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
2278 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
2279 	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
2280 	struct xfs_defer_ops	*dfops,	/* list of extents to be freed */
2281 	int			*logflagsp) /* inode logging flags */
2282 {
2283 	xfs_btree_cur_t		*cur;	/* btree cursor */
2284 	xfs_bmbt_rec_host_t	*ep;	/* extent entry for idx */
2285 	int			error;	/* error return value */
2286 	int			i;	/* temp state */
2287 	xfs_ifork_t		*ifp;	/* inode fork pointer */
2288 	xfs_fileoff_t		new_endoff;	/* end offset of new entry */
2289 	xfs_exntst_t		newext;	/* new extent state */
2290 	xfs_exntst_t		oldext;	/* old extent state */
2291 	xfs_bmbt_irec_t		r[3];	/* neighbor extent entries */
2292 					/* left is 0, right is 1, prev is 2 */
2293 	int			rval=0;	/* return value (logging flags) */
2294 	int			state = 0;/* state bits, accessed thru macros */
2295 	struct xfs_mount	*mp = tp->t_mountp;
2296 
2297 	*logflagsp = 0;
2298 
2299 	cur = *curp;
2300 	ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
2301 
2302 	ASSERT(*idx >= 0);
2303 	ASSERT(*idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
2304 	ASSERT(!isnullstartblock(new->br_startblock));
2305 
2306 	XFS_STATS_INC(mp, xs_add_exlist);
2307 
2308 #define	LEFT		r[0]
2309 #define	RIGHT		r[1]
2310 #define	PREV		r[2]
2311 
2312 	/*
2313 	 * Set up a bunch of variables to make the tests simpler.
2314 	 */
2315 	error = 0;
2316 	ep = xfs_iext_get_ext(ifp, *idx);
2317 	xfs_bmbt_get_all(ep, &PREV);
2318 	newext = new->br_state;
2319 	oldext = (newext == XFS_EXT_UNWRITTEN) ?
2320 		XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
2321 	ASSERT(PREV.br_state == oldext);
2322 	new_endoff = new->br_startoff + new->br_blockcount;
2323 	ASSERT(PREV.br_startoff <= new->br_startoff);
2324 	ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
2325 
2326 	/*
2327 	 * Set flags determining what part of the previous oldext allocation
2328 	 * extent is being replaced by a newext allocation.
2329 	 */
2330 	if (PREV.br_startoff == new->br_startoff)
2331 		state |= BMAP_LEFT_FILLING;
2332 	if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
2333 		state |= BMAP_RIGHT_FILLING;
2334 
2335 	/*
2336 	 * Check and set flags if this segment has a left neighbor.
2337 	 * Don't set contiguous if the combined extent would be too large.
2338 	 */
2339 	if (*idx > 0) {
2340 		state |= BMAP_LEFT_VALID;
2341 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &LEFT);
2342 
2343 		if (isnullstartblock(LEFT.br_startblock))
2344 			state |= BMAP_LEFT_DELAY;
2345 	}
2346 
2347 	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
2348 	    LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
2349 	    LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
2350 	    LEFT.br_state == newext &&
2351 	    LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2352 		state |= BMAP_LEFT_CONTIG;
2353 
2354 	/*
2355 	 * Check and set flags if this segment has a right neighbor.
2356 	 * Don't set contiguous if the combined extent would be too large.
2357 	 * Also check for all-three-contiguous being too large.
2358 	 */
2359 	if (*idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
2360 		state |= BMAP_RIGHT_VALID;
2361 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx + 1), &RIGHT);
2362 		if (isnullstartblock(RIGHT.br_startblock))
2363 			state |= BMAP_RIGHT_DELAY;
2364 	}
2365 
2366 	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
2367 	    new_endoff == RIGHT.br_startoff &&
2368 	    new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
2369 	    newext == RIGHT.br_state &&
2370 	    new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
2371 	    ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2372 		       BMAP_RIGHT_FILLING)) !=
2373 		      (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2374 		       BMAP_RIGHT_FILLING) ||
2375 	     LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
2376 			<= MAXEXTLEN))
2377 		state |= BMAP_RIGHT_CONTIG;
2378 
2379 	/*
2380 	 * Switch out based on the FILLING and CONTIG state bits.
2381 	 */
2382 	switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2383 			 BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
2384 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2385 	     BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2386 		/*
2387 		 * Setting all of a previous oldext extent to newext.
2388 		 * The left and right neighbors are both contiguous with new.
2389 		 */
2390 		--*idx;
2391 
2392 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2393 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
2394 			LEFT.br_blockcount + PREV.br_blockcount +
2395 			RIGHT.br_blockcount);
2396 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2397 
2398 		xfs_iext_remove(ip, *idx + 1, 2, state);
2399 		ip->i_d.di_nextents -= 2;
2400 		if (cur == NULL)
2401 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2402 		else {
2403 			rval = XFS_ILOG_CORE;
2404 			if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
2405 					RIGHT.br_startblock,
2406 					RIGHT.br_blockcount, &i)))
2407 				goto done;
2408 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2409 			if ((error = xfs_btree_delete(cur, &i)))
2410 				goto done;
2411 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2412 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2413 				goto done;
2414 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2415 			if ((error = xfs_btree_delete(cur, &i)))
2416 				goto done;
2417 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2418 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2419 				goto done;
2420 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2421 			if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
2422 				LEFT.br_startblock,
2423 				LEFT.br_blockcount + PREV.br_blockcount +
2424 				RIGHT.br_blockcount, LEFT.br_state)))
2425 				goto done;
2426 		}
2427 		break;
2428 
2429 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2430 		/*
2431 		 * Setting all of a previous oldext extent to newext.
2432 		 * The left neighbor is contiguous, the right is not.
2433 		 */
2434 		--*idx;
2435 
2436 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2437 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
2438 			LEFT.br_blockcount + PREV.br_blockcount);
2439 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2440 
2441 		xfs_iext_remove(ip, *idx + 1, 1, state);
2442 		ip->i_d.di_nextents--;
2443 		if (cur == NULL)
2444 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2445 		else {
2446 			rval = XFS_ILOG_CORE;
2447 			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
2448 					PREV.br_startblock, PREV.br_blockcount,
2449 					&i)))
2450 				goto done;
2451 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2452 			if ((error = xfs_btree_delete(cur, &i)))
2453 				goto done;
2454 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2455 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2456 				goto done;
2457 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2458 			if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
2459 				LEFT.br_startblock,
2460 				LEFT.br_blockcount + PREV.br_blockcount,
2461 				LEFT.br_state)))
2462 				goto done;
2463 		}
2464 		break;
2465 
2466 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2467 		/*
2468 		 * Setting all of a previous oldext extent to newext.
2469 		 * The right neighbor is contiguous, the left is not.
2470 		 */
2471 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2472 		xfs_bmbt_set_blockcount(ep,
2473 			PREV.br_blockcount + RIGHT.br_blockcount);
2474 		xfs_bmbt_set_state(ep, newext);
2475 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2476 		xfs_iext_remove(ip, *idx + 1, 1, state);
2477 		ip->i_d.di_nextents--;
2478 		if (cur == NULL)
2479 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2480 		else {
2481 			rval = XFS_ILOG_CORE;
2482 			if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
2483 					RIGHT.br_startblock,
2484 					RIGHT.br_blockcount, &i)))
2485 				goto done;
2486 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2487 			if ((error = xfs_btree_delete(cur, &i)))
2488 				goto done;
2489 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2490 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2491 				goto done;
2492 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2493 			if ((error = xfs_bmbt_update(cur, new->br_startoff,
2494 				new->br_startblock,
2495 				new->br_blockcount + RIGHT.br_blockcount,
2496 				newext)))
2497 				goto done;
2498 		}
2499 		break;
2500 
2501 	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
2502 		/*
2503 		 * Setting all of a previous oldext extent to newext.
2504 		 * Neither the left nor right neighbors are contiguous with
2505 		 * the new one.
2506 		 */
2507 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2508 		xfs_bmbt_set_state(ep, newext);
2509 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2510 
2511 		if (cur == NULL)
2512 			rval = XFS_ILOG_DEXT;
2513 		else {
2514 			rval = 0;
2515 			if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
2516 					new->br_startblock, new->br_blockcount,
2517 					&i)))
2518 				goto done;
2519 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2520 			if ((error = xfs_bmbt_update(cur, new->br_startoff,
2521 				new->br_startblock, new->br_blockcount,
2522 				newext)))
2523 				goto done;
2524 		}
2525 		break;
2526 
2527 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
2528 		/*
2529 		 * Setting the first part of a previous oldext extent to newext.
2530 		 * The left neighbor is contiguous.
2531 		 */
2532 		trace_xfs_bmap_pre_update(ip, *idx - 1, state, _THIS_IP_);
2533 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx - 1),
2534 			LEFT.br_blockcount + new->br_blockcount);
2535 		xfs_bmbt_set_startoff(ep,
2536 			PREV.br_startoff + new->br_blockcount);
2537 		trace_xfs_bmap_post_update(ip, *idx - 1, state, _THIS_IP_);
2538 
2539 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2540 		xfs_bmbt_set_startblock(ep,
2541 			new->br_startblock + new->br_blockcount);
2542 		xfs_bmbt_set_blockcount(ep,
2543 			PREV.br_blockcount - new->br_blockcount);
2544 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2545 
2546 		--*idx;
2547 
2548 		if (cur == NULL)
2549 			rval = XFS_ILOG_DEXT;
2550 		else {
2551 			rval = 0;
2552 			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
2553 					PREV.br_startblock, PREV.br_blockcount,
2554 					&i)))
2555 				goto done;
2556 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2557 			if ((error = xfs_bmbt_update(cur,
2558 				PREV.br_startoff + new->br_blockcount,
2559 				PREV.br_startblock + new->br_blockcount,
2560 				PREV.br_blockcount - new->br_blockcount,
2561 				oldext)))
2562 				goto done;
2563 			if ((error = xfs_btree_decrement(cur, 0, &i)))
2564 				goto done;
2565 			error = xfs_bmbt_update(cur, LEFT.br_startoff,
2566 				LEFT.br_startblock,
2567 				LEFT.br_blockcount + new->br_blockcount,
2568 				LEFT.br_state);
2569 			if (error)
2570 				goto done;
2571 		}
2572 		break;
2573 
2574 	case BMAP_LEFT_FILLING:
2575 		/*
2576 		 * Setting the first part of a previous oldext extent to newext.
2577 		 * The left neighbor is not contiguous.
2578 		 */
2579 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2580 		ASSERT(ep && xfs_bmbt_get_state(ep) == oldext);
2581 		xfs_bmbt_set_startoff(ep, new_endoff);
2582 		xfs_bmbt_set_blockcount(ep,
2583 			PREV.br_blockcount - new->br_blockcount);
2584 		xfs_bmbt_set_startblock(ep,
2585 			new->br_startblock + new->br_blockcount);
2586 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2587 
2588 		xfs_iext_insert(ip, *idx, 1, new, state);
2589 		ip->i_d.di_nextents++;
2590 		if (cur == NULL)
2591 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2592 		else {
2593 			rval = XFS_ILOG_CORE;
2594 			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
2595 					PREV.br_startblock, PREV.br_blockcount,
2596 					&i)))
2597 				goto done;
2598 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2599 			if ((error = xfs_bmbt_update(cur,
2600 				PREV.br_startoff + new->br_blockcount,
2601 				PREV.br_startblock + new->br_blockcount,
2602 				PREV.br_blockcount - new->br_blockcount,
2603 				oldext)))
2604 				goto done;
2605 			cur->bc_rec.b = *new;
2606 			if ((error = xfs_btree_insert(cur, &i)))
2607 				goto done;
2608 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2609 		}
2610 		break;
2611 
2612 	case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2613 		/*
2614 		 * Setting the last part of a previous oldext extent to newext.
2615 		 * The right neighbor is contiguous with the new allocation.
2616 		 */
2617 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2618 		xfs_bmbt_set_blockcount(ep,
2619 			PREV.br_blockcount - new->br_blockcount);
2620 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2621 
2622 		++*idx;
2623 
2624 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2625 		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
2626 			new->br_startoff, new->br_startblock,
2627 			new->br_blockcount + RIGHT.br_blockcount, newext);
2628 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2629 
2630 		if (cur == NULL)
2631 			rval = XFS_ILOG_DEXT;
2632 		else {
2633 			rval = 0;
2634 			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
2635 					PREV.br_startblock,
2636 					PREV.br_blockcount, &i)))
2637 				goto done;
2638 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2639 			if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
2640 				PREV.br_startblock,
2641 				PREV.br_blockcount - new->br_blockcount,
2642 				oldext)))
2643 				goto done;
2644 			if ((error = xfs_btree_increment(cur, 0, &i)))
2645 				goto done;
2646 			if ((error = xfs_bmbt_update(cur, new->br_startoff,
2647 				new->br_startblock,
2648 				new->br_blockcount + RIGHT.br_blockcount,
2649 				newext)))
2650 				goto done;
2651 		}
2652 		break;
2653 
2654 	case BMAP_RIGHT_FILLING:
2655 		/*
2656 		 * Setting the last part of a previous oldext extent to newext.
2657 		 * The right neighbor is not contiguous.
2658 		 */
2659 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2660 		xfs_bmbt_set_blockcount(ep,
2661 			PREV.br_blockcount - new->br_blockcount);
2662 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2663 
2664 		++*idx;
2665 		xfs_iext_insert(ip, *idx, 1, new, state);
2666 
2667 		ip->i_d.di_nextents++;
2668 		if (cur == NULL)
2669 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2670 		else {
2671 			rval = XFS_ILOG_CORE;
2672 			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
2673 					PREV.br_startblock, PREV.br_blockcount,
2674 					&i)))
2675 				goto done;
2676 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2677 			if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
2678 				PREV.br_startblock,
2679 				PREV.br_blockcount - new->br_blockcount,
2680 				oldext)))
2681 				goto done;
2682 			if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
2683 					new->br_startblock, new->br_blockcount,
2684 					&i)))
2685 				goto done;
2686 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2687 			cur->bc_rec.b.br_state = XFS_EXT_NORM;
2688 			if ((error = xfs_btree_insert(cur, &i)))
2689 				goto done;
2690 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2691 		}
2692 		break;
2693 
2694 	case 0:
2695 		/*
2696 		 * Setting the middle part of a previous oldext extent to
2697 		 * newext.  Contiguity is impossible here.
2698 		 * One extent becomes three extents.
2699 		 */
2700 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2701 		xfs_bmbt_set_blockcount(ep,
2702 			new->br_startoff - PREV.br_startoff);
2703 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2704 
2705 		r[0] = *new;
2706 		r[1].br_startoff = new_endoff;
2707 		r[1].br_blockcount =
2708 			PREV.br_startoff + PREV.br_blockcount - new_endoff;
2709 		r[1].br_startblock = new->br_startblock + new->br_blockcount;
2710 		r[1].br_state = oldext;
2711 
2712 		++*idx;
2713 		xfs_iext_insert(ip, *idx, 2, &r[0], state);
2714 
2715 		ip->i_d.di_nextents += 2;
2716 		if (cur == NULL)
2717 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2718 		else {
2719 			rval = XFS_ILOG_CORE;
2720 			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
2721 					PREV.br_startblock, PREV.br_blockcount,
2722 					&i)))
2723 				goto done;
2724 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2725 			/* new right extent - oldext */
2726 			if ((error = xfs_bmbt_update(cur, r[1].br_startoff,
2727 				r[1].br_startblock, r[1].br_blockcount,
2728 				r[1].br_state)))
2729 				goto done;
2730 			/* new left extent - oldext */
2731 			cur->bc_rec.b = PREV;
2732 			cur->bc_rec.b.br_blockcount =
2733 				new->br_startoff - PREV.br_startoff;
2734 			if ((error = xfs_btree_insert(cur, &i)))
2735 				goto done;
2736 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2737 			/*
2738 			 * Reset the cursor to the position of the new extent
2739 			 * we are about to insert as we can't trust it after
2740 			 * the previous insert.
2741 			 */
2742 			if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
2743 					new->br_startblock, new->br_blockcount,
2744 					&i)))
2745 				goto done;
2746 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2747 			/* new middle extent - newext */
2748 			cur->bc_rec.b.br_state = new->br_state;
2749 			if ((error = xfs_btree_insert(cur, &i)))
2750 				goto done;
2751 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2752 		}
2753 		break;
2754 
2755 	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2756 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2757 	case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
2758 	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2759 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2760 	case BMAP_LEFT_CONTIG:
2761 	case BMAP_RIGHT_CONTIG:
2762 		/*
2763 		 * These cases are all impossible.
2764 		 */
2765 		ASSERT(0);
2766 	}
2767 
2768 	/* update reverse mappings */
2769 	error = xfs_rmap_convert_extent(mp, dfops, ip, XFS_DATA_FORK, new);
2770 	if (error)
2771 		goto done;
2772 
2773 	/* convert to a btree if necessary */
2774 	if (xfs_bmap_needs_btree(ip, XFS_DATA_FORK)) {
2775 		int	tmp_logflags;	/* partial log flag return val */
2776 
2777 		ASSERT(cur == NULL);
2778 		error = xfs_bmap_extents_to_btree(tp, ip, first, dfops, &cur,
2779 				0, &tmp_logflags, XFS_DATA_FORK);
2780 		*logflagsp |= tmp_logflags;
2781 		if (error)
2782 			goto done;
2783 	}
2784 
2785 	/* clear out the allocated field, done with it now in any case. */
2786 	if (cur) {
2787 		cur->bc_private.b.allocated = 0;
2788 		*curp = cur;
2789 	}
2790 
2791 	xfs_bmap_check_leaf_extents(*curp, ip, XFS_DATA_FORK);
2792 done:
2793 	*logflagsp |= rval;
2794 	return error;
2795 #undef	LEFT
2796 #undef	RIGHT
2797 #undef	PREV
2798 }
2799 
2800 /*
2801  * Convert a hole to a delayed allocation.
2802  */
2803 STATIC void
2804 xfs_bmap_add_extent_hole_delay(
2805 	xfs_inode_t		*ip,	/* incore inode pointer */
2806 	int			whichfork,
2807 	xfs_extnum_t		*idx,	/* extent number to update/insert */
2808 	xfs_bmbt_irec_t		*new)	/* new data to add to file extents */
2809 {
2810 	xfs_ifork_t		*ifp;	/* inode fork pointer */
2811 	xfs_bmbt_irec_t		left;	/* left neighbor extent entry */
2812 	xfs_filblks_t		newlen=0;	/* new indirect size */
2813 	xfs_filblks_t		oldlen=0;	/* old indirect size */
2814 	xfs_bmbt_irec_t		right;	/* right neighbor extent entry */
2815 	int			state;  /* state bits, accessed thru macros */
2816 	xfs_filblks_t		temp=0;	/* temp for indirect calculations */
2817 
2818 	ifp = XFS_IFORK_PTR(ip, whichfork);
2819 	state = 0;
2820 	if (whichfork == XFS_COW_FORK)
2821 		state |= BMAP_COWFORK;
2822 	ASSERT(isnullstartblock(new->br_startblock));
2823 
2824 	/*
2825 	 * Check and set flags if this segment has a left neighbor
2826 	 */
2827 	if (*idx > 0) {
2828 		state |= BMAP_LEFT_VALID;
2829 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &left);
2830 
2831 		if (isnullstartblock(left.br_startblock))
2832 			state |= BMAP_LEFT_DELAY;
2833 	}
2834 
2835 	/*
2836 	 * Check and set flags if the current (right) segment exists.
2837 	 * If it doesn't exist, we're converting the hole at end-of-file.
2838 	 */
2839 	if (*idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
2840 		state |= BMAP_RIGHT_VALID;
2841 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx), &right);
2842 
2843 		if (isnullstartblock(right.br_startblock))
2844 			state |= BMAP_RIGHT_DELAY;
2845 	}
2846 
2847 	/*
2848 	 * Set contiguity flags on the left and right neighbors.
2849 	 * Don't let extents get too large, even if the pieces are contiguous.
2850 	 */
2851 	if ((state & BMAP_LEFT_VALID) && (state & BMAP_LEFT_DELAY) &&
2852 	    left.br_startoff + left.br_blockcount == new->br_startoff &&
2853 	    left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
2854 		state |= BMAP_LEFT_CONTIG;
2855 
2856 	if ((state & BMAP_RIGHT_VALID) && (state & BMAP_RIGHT_DELAY) &&
2857 	    new->br_startoff + new->br_blockcount == right.br_startoff &&
2858 	    new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
2859 	    (!(state & BMAP_LEFT_CONTIG) ||
2860 	     (left.br_blockcount + new->br_blockcount +
2861 	      right.br_blockcount <= MAXEXTLEN)))
2862 		state |= BMAP_RIGHT_CONTIG;
2863 
2864 	/*
2865 	 * Switch out based on the contiguity flags.
2866 	 */
2867 	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
2868 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2869 		/*
2870 		 * New allocation is contiguous with delayed allocations
2871 		 * on the left and on the right.
2872 		 * Merge all three into a single extent record.
2873 		 */
2874 		--*idx;
2875 		temp = left.br_blockcount + new->br_blockcount +
2876 			right.br_blockcount;
2877 
2878 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2879 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx), temp);
2880 		oldlen = startblockval(left.br_startblock) +
2881 			startblockval(new->br_startblock) +
2882 			startblockval(right.br_startblock);
2883 		newlen = xfs_bmap_worst_indlen(ip, temp);
2884 		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, *idx),
2885 			nullstartblock((int)newlen));
2886 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2887 
2888 		xfs_iext_remove(ip, *idx + 1, 1, state);
2889 		break;
2890 
2891 	case BMAP_LEFT_CONTIG:
2892 		/*
2893 		 * New allocation is contiguous with a delayed allocation
2894 		 * on the left.
2895 		 * Merge the new allocation with the left neighbor.
2896 		 */
2897 		--*idx;
2898 		temp = left.br_blockcount + new->br_blockcount;
2899 
2900 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2901 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx), temp);
2902 		oldlen = startblockval(left.br_startblock) +
2903 			startblockval(new->br_startblock);
2904 		newlen = xfs_bmap_worst_indlen(ip, temp);
2905 		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, *idx),
2906 			nullstartblock((int)newlen));
2907 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2908 		break;
2909 
2910 	case BMAP_RIGHT_CONTIG:
2911 		/*
2912 		 * New allocation is contiguous with a delayed allocation
2913 		 * on the right.
2914 		 * Merge the new allocation with the right neighbor.
2915 		 */
2916 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
2917 		temp = new->br_blockcount + right.br_blockcount;
2918 		oldlen = startblockval(new->br_startblock) +
2919 			startblockval(right.br_startblock);
2920 		newlen = xfs_bmap_worst_indlen(ip, temp);
2921 		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
2922 			new->br_startoff,
2923 			nullstartblock((int)newlen), temp, right.br_state);
2924 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2925 		break;
2926 
2927 	case 0:
2928 		/*
2929 		 * New allocation is not contiguous with another
2930 		 * delayed allocation.
2931 		 * Insert a new entry.
2932 		 */
2933 		oldlen = newlen = 0;
2934 		xfs_iext_insert(ip, *idx, 1, new, state);
2935 		break;
2936 	}
2937 	if (oldlen != newlen) {
2938 		ASSERT(oldlen > newlen);
2939 		xfs_mod_fdblocks(ip->i_mount, (int64_t)(oldlen - newlen),
2940 				 false);
2941 		/*
2942 		 * Nothing to do for disk quota accounting here.
2943 		 */
2944 	}
2945 }
2946 
2947 /*
2948  * Convert a hole to a real allocation.
2949  */
2950 STATIC int				/* error */
2951 xfs_bmap_add_extent_hole_real(
2952 	struct xfs_bmalloca	*bma,
2953 	int			whichfork)
2954 {
2955 	struct xfs_bmbt_irec	*new = &bma->got;
2956 	int			error;	/* error return value */
2957 	int			i;	/* temp state */
2958 	xfs_ifork_t		*ifp;	/* inode fork pointer */
2959 	xfs_bmbt_irec_t		left;	/* left neighbor extent entry */
2960 	xfs_bmbt_irec_t		right;	/* right neighbor extent entry */
2961 	int			rval=0;	/* return value (logging flags) */
2962 	int			state;	/* state bits, accessed thru macros */
2963 	struct xfs_mount	*mp;
2964 
2965 	mp = bma->ip->i_mount;
2966 	ifp = XFS_IFORK_PTR(bma->ip, whichfork);
2967 
2968 	ASSERT(bma->idx >= 0);
2969 	ASSERT(bma->idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
2970 	ASSERT(!isnullstartblock(new->br_startblock));
2971 	ASSERT(!bma->cur ||
2972 	       !(bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
2973 	ASSERT(whichfork != XFS_COW_FORK);
2974 
2975 	XFS_STATS_INC(mp, xs_add_exlist);
2976 
2977 	state = 0;
2978 	if (whichfork == XFS_ATTR_FORK)
2979 		state |= BMAP_ATTRFORK;
2980 
2981 	/*
2982 	 * Check and set flags if this segment has a left neighbor.
2983 	 */
2984 	if (bma->idx > 0) {
2985 		state |= BMAP_LEFT_VALID;
2986 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx - 1), &left);
2987 		if (isnullstartblock(left.br_startblock))
2988 			state |= BMAP_LEFT_DELAY;
2989 	}
2990 
2991 	/*
2992 	 * Check and set flags if this segment has a current value.
2993 	 * Not true if we're inserting into the "hole" at eof.
2994 	 */
2995 	if (bma->idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
2996 		state |= BMAP_RIGHT_VALID;
2997 		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx), &right);
2998 		if (isnullstartblock(right.br_startblock))
2999 			state |= BMAP_RIGHT_DELAY;
3000 	}
3001 
3002 	/*
3003 	 * We're inserting a real allocation between "left" and "right".
3004 	 * Set the contiguity flags.  Don't let extents get too large.
3005 	 */
3006 	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
3007 	    left.br_startoff + left.br_blockcount == new->br_startoff &&
3008 	    left.br_startblock + left.br_blockcount == new->br_startblock &&
3009 	    left.br_state == new->br_state &&
3010 	    left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
3011 		state |= BMAP_LEFT_CONTIG;
3012 
3013 	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
3014 	    new->br_startoff + new->br_blockcount == right.br_startoff &&
3015 	    new->br_startblock + new->br_blockcount == right.br_startblock &&
3016 	    new->br_state == right.br_state &&
3017 	    new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
3018 	    (!(state & BMAP_LEFT_CONTIG) ||
3019 	     left.br_blockcount + new->br_blockcount +
3020 	     right.br_blockcount <= MAXEXTLEN))
3021 		state |= BMAP_RIGHT_CONTIG;
3022 
3023 	error = 0;
3024 	/*
3025 	 * Select which case we're in here, and implement it.
3026 	 */
3027 	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
3028 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
3029 		/*
3030 		 * New allocation is contiguous with real allocations on the
3031 		 * left and on the right.
3032 		 * Merge all three into a single extent record.
3033 		 */
3034 		--bma->idx;
3035 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
3036 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
3037 			left.br_blockcount + new->br_blockcount +
3038 			right.br_blockcount);
3039 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
3040 
3041 		xfs_iext_remove(bma->ip, bma->idx + 1, 1, state);
3042 
3043 		XFS_IFORK_NEXT_SET(bma->ip, whichfork,
3044 			XFS_IFORK_NEXTENTS(bma->ip, whichfork) - 1);
3045 		if (bma->cur == NULL) {
3046 			rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
3047 		} else {
3048 			rval = XFS_ILOG_CORE;
3049 			error = xfs_bmbt_lookup_eq(bma->cur, right.br_startoff,
3050 					right.br_startblock, right.br_blockcount,
3051 					&i);
3052 			if (error)
3053 				goto done;
3054 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3055 			error = xfs_btree_delete(bma->cur, &i);
3056 			if (error)
3057 				goto done;
3058 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3059 			error = xfs_btree_decrement(bma->cur, 0, &i);
3060 			if (error)
3061 				goto done;
3062 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3063 			error = xfs_bmbt_update(bma->cur, left.br_startoff,
3064 					left.br_startblock,
3065 					left.br_blockcount +
3066 						new->br_blockcount +
3067 						right.br_blockcount,
3068 					left.br_state);
3069 			if (error)
3070 				goto done;
3071 		}
3072 		break;
3073 
3074 	case BMAP_LEFT_CONTIG:
3075 		/*
3076 		 * New allocation is contiguous with a real allocation
3077 		 * on the left.
3078 		 * Merge the new allocation with the left neighbor.
3079 		 */
3080 		--bma->idx;
3081 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
3082 		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
3083 			left.br_blockcount + new->br_blockcount);
3084 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
3085 
3086 		if (bma->cur == NULL) {
3087 			rval = xfs_ilog_fext(whichfork);
3088 		} else {
3089 			rval = 0;
3090 			error = xfs_bmbt_lookup_eq(bma->cur, left.br_startoff,
3091 					left.br_startblock, left.br_blockcount,
3092 					&i);
3093 			if (error)
3094 				goto done;
3095 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3096 			error = xfs_bmbt_update(bma->cur, left.br_startoff,
3097 					left.br_startblock,
3098 					left.br_blockcount +
3099 						new->br_blockcount,
3100 					left.br_state);
3101 			if (error)
3102 				goto done;
3103 		}
3104 		break;
3105 
3106 	case BMAP_RIGHT_CONTIG:
3107 		/*
3108 		 * New allocation is contiguous with a real allocation
3109 		 * on the right.
3110 		 * Merge the new allocation with the right neighbor.
3111 		 */
3112 		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
3113 		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, bma->idx),
3114 			new->br_startoff, new->br_startblock,
3115 			new->br_blockcount + right.br_blockcount,
3116 			right.br_state);
3117 		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
3118 
3119 		if (bma->cur == NULL) {
3120 			rval = xfs_ilog_fext(whichfork);
3121 		} else {
3122 			rval = 0;
3123 			error = xfs_bmbt_lookup_eq(bma->cur,
3124 					right.br_startoff,
3125 					right.br_startblock,
3126 					right.br_blockcount, &i);
3127 			if (error)
3128 				goto done;
3129 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3130 			error = xfs_bmbt_update(bma->cur, new->br_startoff,
3131 					new->br_startblock,
3132 					new->br_blockcount +
3133 						right.br_blockcount,
3134 					right.br_state);
3135 			if (error)
3136 				goto done;
3137 		}
3138 		break;
3139 
3140 	case 0:
3141 		/*
3142 		 * New allocation is not contiguous with another
3143 		 * real allocation.
3144 		 * Insert a new entry.
3145 		 */
3146 		xfs_iext_insert(bma->ip, bma->idx, 1, new, state);
3147 		XFS_IFORK_NEXT_SET(bma->ip, whichfork,
3148 			XFS_IFORK_NEXTENTS(bma->ip, whichfork) + 1);
3149 		if (bma->cur == NULL) {
3150 			rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
3151 		} else {
3152 			rval = XFS_ILOG_CORE;
3153 			error = xfs_bmbt_lookup_eq(bma->cur,
3154 					new->br_startoff,
3155 					new->br_startblock,
3156 					new->br_blockcount, &i);
3157 			if (error)
3158 				goto done;
3159 			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
3160 			bma->cur->bc_rec.b.br_state = new->br_state;
3161 			error = xfs_btree_insert(bma->cur, &i);
3162 			if (error)
3163 				goto done;
3164 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3165 		}
3166 		break;
3167 	}
3168 
3169 	/* add reverse mapping */
3170 	error = xfs_rmap_map_extent(mp, bma->dfops, bma->ip, whichfork, new);
3171 	if (error)
3172 		goto done;
3173 
3174 	/* convert to a btree if necessary */
3175 	if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
3176 		int	tmp_logflags;	/* partial log flag return val */
3177 
3178 		ASSERT(bma->cur == NULL);
3179 		error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
3180 				bma->firstblock, bma->dfops, &bma->cur,
3181 				0, &tmp_logflags, whichfork);
3182 		bma->logflags |= tmp_logflags;
3183 		if (error)
3184 			goto done;
3185 	}
3186 
3187 	/* clear out the allocated field, done with it now in any case. */
3188 	if (bma->cur)
3189 		bma->cur->bc_private.b.allocated = 0;
3190 
3191 	xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
3192 done:
3193 	bma->logflags |= rval;
3194 	return error;
3195 }
3196 
3197 /*
3198  * Functions used in the extent read, allocate and remove paths
3199  */
3200 
3201 /*
3202  * Adjust the size of the new extent based on di_extsize and rt extsize.
3203  */
3204 int
3205 xfs_bmap_extsize_align(
3206 	xfs_mount_t	*mp,
3207 	xfs_bmbt_irec_t	*gotp,		/* next extent pointer */
3208 	xfs_bmbt_irec_t	*prevp,		/* previous extent pointer */
3209 	xfs_extlen_t	extsz,		/* align to this extent size */
3210 	int		rt,		/* is this a realtime inode? */
3211 	int		eof,		/* is extent at end-of-file? */
3212 	int		delay,		/* creating delalloc extent? */
3213 	int		convert,	/* overwriting unwritten extent? */
3214 	xfs_fileoff_t	*offp,		/* in/out: aligned offset */
3215 	xfs_extlen_t	*lenp)		/* in/out: aligned length */
3216 {
3217 	xfs_fileoff_t	orig_off;	/* original offset */
3218 	xfs_extlen_t	orig_alen;	/* original length */
3219 	xfs_fileoff_t	orig_end;	/* original off+len */
3220 	xfs_fileoff_t	nexto;		/* next file offset */
3221 	xfs_fileoff_t	prevo;		/* previous file offset */
3222 	xfs_fileoff_t	align_off;	/* temp for offset */
3223 	xfs_extlen_t	align_alen;	/* temp for length */
3224 	xfs_extlen_t	temp;		/* temp for calculations */
3225 
3226 	if (convert)
3227 		return 0;
3228 
3229 	orig_off = align_off = *offp;
3230 	orig_alen = align_alen = *lenp;
3231 	orig_end = orig_off + orig_alen;
3232 
3233 	/*
3234 	 * If this request overlaps an existing extent, then don't
3235 	 * attempt to perform any additional alignment.
3236 	 */
3237 	if (!delay && !eof &&
3238 	    (orig_off >= gotp->br_startoff) &&
3239 	    (orig_end <= gotp->br_startoff + gotp->br_blockcount)) {
3240 		return 0;
3241 	}
3242 
3243 	/*
3244 	 * If the file offset is unaligned vs. the extent size
3245 	 * we need to align it.  This will be possible unless
3246 	 * the file was previously written with a kernel that didn't
3247 	 * perform this alignment, or if a truncate shot us in the
3248 	 * foot.
3249 	 */
3250 	temp = do_mod(orig_off, extsz);
3251 	if (temp) {
3252 		align_alen += temp;
3253 		align_off -= temp;
3254 	}
3255 
3256 	/* Same adjustment for the end of the requested area. */
3257 	temp = (align_alen % extsz);
3258 	if (temp)
3259 		align_alen += extsz - temp;
3260 
3261 	/*
3262 	 * For large extent hint sizes, the aligned extent might be larger than
3263 	 * MAXEXTLEN. In that case, reduce the size by an extsz so that it pulls
3264 	 * the length back under MAXEXTLEN. The outer allocation loops handle
3265 	 * short allocation just fine, so it is safe to do this. We only want to
3266 	 * do it when we are forced to, though, because it means more allocation
3267 	 * operations are required.
3268 	 */
3269 	while (align_alen > MAXEXTLEN)
3270 		align_alen -= extsz;
3271 	ASSERT(align_alen <= MAXEXTLEN);
3272 
3273 	/*
3274 	 * If the previous block overlaps with this proposed allocation
3275 	 * then move the start forward without adjusting the length.
3276 	 */
3277 	if (prevp->br_startoff != NULLFILEOFF) {
3278 		if (prevp->br_startblock == HOLESTARTBLOCK)
3279 			prevo = prevp->br_startoff;
3280 		else
3281 			prevo = prevp->br_startoff + prevp->br_blockcount;
3282 	} else
3283 		prevo = 0;
3284 	if (align_off != orig_off && align_off < prevo)
3285 		align_off = prevo;
3286 	/*
3287 	 * If the next block overlaps with this proposed allocation
3288 	 * then move the start back without adjusting the length,
3289 	 * but not before offset 0.
3290 	 * This may of course make the start overlap previous block,
3291 	 * and if we hit the offset 0 limit then the next block
3292 	 * can still overlap too.
3293 	 */
3294 	if (!eof && gotp->br_startoff != NULLFILEOFF) {
3295 		if ((delay && gotp->br_startblock == HOLESTARTBLOCK) ||
3296 		    (!delay && gotp->br_startblock == DELAYSTARTBLOCK))
3297 			nexto = gotp->br_startoff + gotp->br_blockcount;
3298 		else
3299 			nexto = gotp->br_startoff;
3300 	} else
3301 		nexto = NULLFILEOFF;
3302 	if (!eof &&
3303 	    align_off + align_alen != orig_end &&
3304 	    align_off + align_alen > nexto)
3305 		align_off = nexto > align_alen ? nexto - align_alen : 0;
3306 	/*
3307 	 * If we're now overlapping the next or previous extent that
3308 	 * means we can't fit an extsz piece in this hole.  Just move
3309 	 * the start forward to the first valid spot and set
3310 	 * the length so we hit the end.
3311 	 */
3312 	if (align_off != orig_off && align_off < prevo)
3313 		align_off = prevo;
3314 	if (align_off + align_alen != orig_end &&
3315 	    align_off + align_alen > nexto &&
3316 	    nexto != NULLFILEOFF) {
3317 		ASSERT(nexto > prevo);
3318 		align_alen = nexto - align_off;
3319 	}
3320 
3321 	/*
3322 	 * If realtime, and the result isn't a multiple of the realtime
3323 	 * extent size we need to remove blocks until it is.
3324 	 */
3325 	if (rt && (temp = (align_alen % mp->m_sb.sb_rextsize))) {
3326 		/*
3327 		 * We're not covering the original request, or
3328 		 * we won't be able to once we fix the length.
3329 		 */
3330 		if (orig_off < align_off ||
3331 		    orig_end > align_off + align_alen ||
3332 		    align_alen - temp < orig_alen)
3333 			return -EINVAL;
3334 		/*
3335 		 * Try to fix it by moving the start up.
3336 		 */
3337 		if (align_off + temp <= orig_off) {
3338 			align_alen -= temp;
3339 			align_off += temp;
3340 		}
3341 		/*
3342 		 * Try to fix it by moving the end in.
3343 		 */
3344 		else if (align_off + align_alen - temp >= orig_end)
3345 			align_alen -= temp;
3346 		/*
3347 		 * Set the start to the minimum then trim the length.
3348 		 */
3349 		else {
3350 			align_alen -= orig_off - align_off;
3351 			align_off = orig_off;
3352 			align_alen -= align_alen % mp->m_sb.sb_rextsize;
3353 		}
3354 		/*
3355 		 * Result doesn't cover the request, fail it.
3356 		 */
3357 		if (orig_off < align_off || orig_end > align_off + align_alen)
3358 			return -EINVAL;
3359 	} else {
3360 		ASSERT(orig_off >= align_off);
3361 		/* see MAXEXTLEN handling above */
3362 		ASSERT(orig_end <= align_off + align_alen ||
3363 		       align_alen + extsz > MAXEXTLEN);
3364 	}
3365 
3366 #ifdef DEBUG
3367 	if (!eof && gotp->br_startoff != NULLFILEOFF)
3368 		ASSERT(align_off + align_alen <= gotp->br_startoff);
3369 	if (prevp->br_startoff != NULLFILEOFF)
3370 		ASSERT(align_off >= prevp->br_startoff + prevp->br_blockcount);
3371 #endif
3372 
3373 	*lenp = align_alen;
3374 	*offp = align_off;
3375 	return 0;
3376 }
3377 
3378 #define XFS_ALLOC_GAP_UNITS	4
3379 
3380 void
3381 xfs_bmap_adjacent(
3382 	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3383 {
3384 	xfs_fsblock_t	adjust;		/* adjustment to block numbers */
3385 	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */
3386 	xfs_mount_t	*mp;		/* mount point structure */
3387 	int		nullfb;		/* true if ap->firstblock isn't set */
3388 	int		rt;		/* true if inode is realtime */
3389 
3390 #define	ISVALID(x,y)	\
3391 	(rt ? \
3392 		(x) < mp->m_sb.sb_rblocks : \
3393 		XFS_FSB_TO_AGNO(mp, x) == XFS_FSB_TO_AGNO(mp, y) && \
3394 		XFS_FSB_TO_AGNO(mp, x) < mp->m_sb.sb_agcount && \
3395 		XFS_FSB_TO_AGBNO(mp, x) < mp->m_sb.sb_agblocks)
3396 
3397 	mp = ap->ip->i_mount;
3398 	nullfb = *ap->firstblock == NULLFSBLOCK;
3399 	rt = XFS_IS_REALTIME_INODE(ap->ip) &&
3400 		xfs_alloc_is_userdata(ap->datatype);
3401 	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, *ap->firstblock);
3402 	/*
3403 	 * If allocating at eof, and there's a previous real block,
3404 	 * try to use its last block as our starting point.
3405 	 */
3406 	if (ap->eof && ap->prev.br_startoff != NULLFILEOFF &&
3407 	    !isnullstartblock(ap->prev.br_startblock) &&
3408 	    ISVALID(ap->prev.br_startblock + ap->prev.br_blockcount,
3409 		    ap->prev.br_startblock)) {
3410 		ap->blkno = ap->prev.br_startblock + ap->prev.br_blockcount;
3411 		/*
3412 		 * Adjust for the gap between prevp and us.
3413 		 */
3414 		adjust = ap->offset -
3415 			(ap->prev.br_startoff + ap->prev.br_blockcount);
3416 		if (adjust &&
3417 		    ISVALID(ap->blkno + adjust, ap->prev.br_startblock))
3418 			ap->blkno += adjust;
3419 	}
3420 	/*
3421 	 * If not at eof, then compare the two neighbor blocks.
3422 	 * Figure out whether either one gives us a good starting point,
3423 	 * and pick the better one.
3424 	 */
3425 	else if (!ap->eof) {
3426 		xfs_fsblock_t	gotbno;		/* right side block number */
3427 		xfs_fsblock_t	gotdiff=0;	/* right side difference */
3428 		xfs_fsblock_t	prevbno;	/* left side block number */
3429 		xfs_fsblock_t	prevdiff=0;	/* left side difference */
3430 
3431 		/*
3432 		 * If there's a previous (left) block, select a requested
3433 		 * start block based on it.
3434 		 */
3435 		if (ap->prev.br_startoff != NULLFILEOFF &&
3436 		    !isnullstartblock(ap->prev.br_startblock) &&
3437 		    (prevbno = ap->prev.br_startblock +
3438 			       ap->prev.br_blockcount) &&
3439 		    ISVALID(prevbno, ap->prev.br_startblock)) {
3440 			/*
3441 			 * Calculate gap to end of previous block.
3442 			 */
3443 			adjust = prevdiff = ap->offset -
3444 				(ap->prev.br_startoff +
3445 				 ap->prev.br_blockcount);
3446 			/*
3447 			 * Figure the startblock based on the previous block's
3448 			 * end and the gap size.
3449 			 * Heuristic!
3450 			 * If the gap is large relative to the piece we're
3451 			 * allocating, or using it gives us an invalid block
3452 			 * number, then just use the end of the previous block.
3453 			 */
3454 			if (prevdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3455 			    ISVALID(prevbno + prevdiff,
3456 				    ap->prev.br_startblock))
3457 				prevbno += adjust;
3458 			else
3459 				prevdiff += adjust;
3460 			/*
3461 			 * If the firstblock forbids it, can't use it,
3462 			 * must use default.
3463 			 */
3464 			if (!rt && !nullfb &&
3465 			    XFS_FSB_TO_AGNO(mp, prevbno) != fb_agno)
3466 				prevbno = NULLFSBLOCK;
3467 		}
3468 		/*
3469 		 * No previous block or can't follow it, just default.
3470 		 */
3471 		else
3472 			prevbno = NULLFSBLOCK;
3473 		/*
3474 		 * If there's a following (right) block, select a requested
3475 		 * start block based on it.
3476 		 */
3477 		if (!isnullstartblock(ap->got.br_startblock)) {
3478 			/*
3479 			 * Calculate gap to start of next block.
3480 			 */
3481 			adjust = gotdiff = ap->got.br_startoff - ap->offset;
3482 			/*
3483 			 * Figure the startblock based on the next block's
3484 			 * start and the gap size.
3485 			 */
3486 			gotbno = ap->got.br_startblock;
3487 			/*
3488 			 * Heuristic!
3489 			 * If the gap is large relative to the piece we're
3490 			 * allocating, or using it gives us an invalid block
3491 			 * number, then just use the start of the next block
3492 			 * offset by our length.
3493 			 */
3494 			if (gotdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3495 			    ISVALID(gotbno - gotdiff, gotbno))
3496 				gotbno -= adjust;
3497 			else if (ISVALID(gotbno - ap->length, gotbno)) {
3498 				gotbno -= ap->length;
3499 				gotdiff += adjust - ap->length;
3500 			} else
3501 				gotdiff += adjust;
3502 			/*
3503 			 * If the firstblock forbids it, can't use it,
3504 			 * must use default.
3505 			 */
3506 			if (!rt && !nullfb &&
3507 			    XFS_FSB_TO_AGNO(mp, gotbno) != fb_agno)
3508 				gotbno = NULLFSBLOCK;
3509 		}
3510 		/*
3511 		 * No next block, just default.
3512 		 */
3513 		else
3514 			gotbno = NULLFSBLOCK;
3515 		/*
3516 		 * If both valid, pick the better one, else the only good
3517 		 * one, else ap->blkno is already set (to 0 or the inode block).
3518 		 */
3519 		if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK)
3520 			ap->blkno = prevdiff <= gotdiff ? prevbno : gotbno;
3521 		else if (prevbno != NULLFSBLOCK)
3522 			ap->blkno = prevbno;
3523 		else if (gotbno != NULLFSBLOCK)
3524 			ap->blkno = gotbno;
3525 	}
3526 #undef ISVALID
3527 }
3528 
3529 static int
3530 xfs_bmap_longest_free_extent(
3531 	struct xfs_trans	*tp,
3532 	xfs_agnumber_t		ag,
3533 	xfs_extlen_t		*blen,
3534 	int			*notinit)
3535 {
3536 	struct xfs_mount	*mp = tp->t_mountp;
3537 	struct xfs_perag	*pag;
3538 	xfs_extlen_t		longest;
3539 	int			error = 0;
3540 
3541 	pag = xfs_perag_get(mp, ag);
3542 	if (!pag->pagf_init) {
3543 		error = xfs_alloc_pagf_init(mp, tp, ag, XFS_ALLOC_FLAG_TRYLOCK);
3544 		if (error)
3545 			goto out;
3546 
3547 		if (!pag->pagf_init) {
3548 			*notinit = 1;
3549 			goto out;
3550 		}
3551 	}
3552 
3553 	longest = xfs_alloc_longest_free_extent(mp, pag,
3554 				xfs_alloc_min_freelist(mp, pag),
3555 				xfs_ag_resv_needed(pag, XFS_AG_RESV_NONE));
3556 	if (*blen < longest)
3557 		*blen = longest;
3558 
3559 out:
3560 	xfs_perag_put(pag);
3561 	return error;
3562 }
3563 
3564 static void
3565 xfs_bmap_select_minlen(
3566 	struct xfs_bmalloca	*ap,
3567 	struct xfs_alloc_arg	*args,
3568 	xfs_extlen_t		*blen,
3569 	int			notinit)
3570 {
3571 	if (notinit || *blen < ap->minlen) {
3572 		/*
3573 		 * Since we did a BUF_TRYLOCK above, it is possible that
3574 		 * there is space for this request.
3575 		 */
3576 		args->minlen = ap->minlen;
3577 	} else if (*blen < args->maxlen) {
3578 		/*
3579 		 * If the best seen length is less than the request length,
3580 		 * use the best as the minimum.
3581 		 */
3582 		args->minlen = *blen;
3583 	} else {
3584 		/*
3585 		 * Otherwise we've seen an extent as big as maxlen, use that
3586 		 * as the minimum.
3587 		 */
3588 		args->minlen = args->maxlen;
3589 	}
3590 }
3591 
3592 STATIC int
3593 xfs_bmap_btalloc_nullfb(
3594 	struct xfs_bmalloca	*ap,
3595 	struct xfs_alloc_arg	*args,
3596 	xfs_extlen_t		*blen)
3597 {
3598 	struct xfs_mount	*mp = ap->ip->i_mount;
3599 	xfs_agnumber_t		ag, startag;
3600 	int			notinit = 0;
3601 	int			error;
3602 
3603 	args->type = XFS_ALLOCTYPE_START_BNO;
3604 	args->total = ap->total;
3605 
3606 	startag = ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
3607 	if (startag == NULLAGNUMBER)
3608 		startag = ag = 0;
3609 
3610 	while (*blen < args->maxlen) {
3611 		error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
3612 						     &notinit);
3613 		if (error)
3614 			return error;
3615 
3616 		if (++ag == mp->m_sb.sb_agcount)
3617 			ag = 0;
3618 		if (ag == startag)
3619 			break;
3620 	}
3621 
3622 	xfs_bmap_select_minlen(ap, args, blen, notinit);
3623 	return 0;
3624 }
3625 
3626 STATIC int
3627 xfs_bmap_btalloc_filestreams(
3628 	struct xfs_bmalloca	*ap,
3629 	struct xfs_alloc_arg	*args,
3630 	xfs_extlen_t		*blen)
3631 {
3632 	struct xfs_mount	*mp = ap->ip->i_mount;
3633 	xfs_agnumber_t		ag;
3634 	int			notinit = 0;
3635 	int			error;
3636 
3637 	args->type = XFS_ALLOCTYPE_NEAR_BNO;
3638 	args->total = ap->total;
3639 
3640 	ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
3641 	if (ag == NULLAGNUMBER)
3642 		ag = 0;
3643 
3644 	error = xfs_bmap_longest_free_extent(args->tp, ag, blen, &notinit);
3645 	if (error)
3646 		return error;
3647 
3648 	if (*blen < args->maxlen) {
3649 		error = xfs_filestream_new_ag(ap, &ag);
3650 		if (error)
3651 			return error;
3652 
3653 		error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
3654 						     &notinit);
3655 		if (error)
3656 			return error;
3657 
3658 	}
3659 
3660 	xfs_bmap_select_minlen(ap, args, blen, notinit);
3661 
3662 	/*
3663 	 * Set the failure fallback case to look in the selected AG as stream
3664 	 * may have moved.
3665 	 */
3666 	ap->blkno = args->fsbno = XFS_AGB_TO_FSB(mp, ag, 0);
3667 	return 0;
3668 }
3669 
3670 STATIC int
3671 xfs_bmap_btalloc(
3672 	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3673 {
3674 	xfs_mount_t	*mp;		/* mount point structure */
3675 	xfs_alloctype_t	atype = 0;	/* type for allocation routines */
3676 	xfs_extlen_t	align = 0;	/* minimum allocation alignment */
3677 	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */
3678 	xfs_agnumber_t	ag;
3679 	xfs_alloc_arg_t	args;
3680 	xfs_extlen_t	blen;
3681 	xfs_extlen_t	nextminlen = 0;
3682 	int		nullfb;		/* true if ap->firstblock isn't set */
3683 	int		isaligned;
3684 	int		tryagain;
3685 	int		error;
3686 	int		stripe_align;
3687 
3688 	ASSERT(ap->length);
3689 
3690 	mp = ap->ip->i_mount;
3691 
3692 	/* stripe alignment for allocation is determined by mount parameters */
3693 	stripe_align = 0;
3694 	if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC))
3695 		stripe_align = mp->m_swidth;
3696 	else if (mp->m_dalign)
3697 		stripe_align = mp->m_dalign;
3698 
3699 	if (ap->flags & XFS_BMAPI_COWFORK)
3700 		align = xfs_get_cowextsz_hint(ap->ip);
3701 	else if (xfs_alloc_is_userdata(ap->datatype))
3702 		align = xfs_get_extsz_hint(ap->ip);
3703 	if (unlikely(align)) {
3704 		error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
3705 						align, 0, ap->eof, 0, ap->conv,
3706 						&ap->offset, &ap->length);
3707 		ASSERT(!error);
3708 		ASSERT(ap->length);
3709 	}
3710 
3711 
3712 	nullfb = *ap->firstblock == NULLFSBLOCK;
3713 	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, *ap->firstblock);
3714 	if (nullfb) {
3715 		if (xfs_alloc_is_userdata(ap->datatype) &&
3716 		    xfs_inode_is_filestream(ap->ip)) {
3717 			ag = xfs_filestream_lookup_ag(ap->ip);
3718 			ag = (ag != NULLAGNUMBER) ? ag : 0;
3719 			ap->blkno = XFS_AGB_TO_FSB(mp, ag, 0);
3720 		} else {
3721 			ap->blkno = XFS_INO_TO_FSB(mp, ap->ip->i_ino);
3722 		}
3723 	} else
3724 		ap->blkno = *ap->firstblock;
3725 
3726 	xfs_bmap_adjacent(ap);
3727 
3728 	/*
3729 	 * If allowed, use ap->blkno; otherwise must use firstblock since
3730 	 * it's in the right allocation group.
3731 	 */
3732 	if (nullfb || XFS_FSB_TO_AGNO(mp, ap->blkno) == fb_agno)
3733 		;
3734 	else
3735 		ap->blkno = *ap->firstblock;
3736 	/*
3737 	 * Normal allocation, done through xfs_alloc_vextent.
3738 	 */
3739 	tryagain = isaligned = 0;
3740 	memset(&args, 0, sizeof(args));
3741 	args.tp = ap->tp;
3742 	args.mp = mp;
3743 	args.fsbno = ap->blkno;
3744 	xfs_rmap_skip_owner_update(&args.oinfo);
3745 
3746 	/* Trim the allocation back to the maximum an AG can fit. */
3747 	args.maxlen = MIN(ap->length, mp->m_ag_max_usable);
3748 	args.firstblock = *ap->firstblock;
3749 	blen = 0;
3750 	if (nullfb) {
3751 		/*
3752 		 * Search for an allocation group with a single extent large
3753 		 * enough for the request.  If one isn't found, then adjust
3754 		 * the minimum allocation size to the largest space found.
3755 		 */
3756 		if (xfs_alloc_is_userdata(ap->datatype) &&
3757 		    xfs_inode_is_filestream(ap->ip))
3758 			error = xfs_bmap_btalloc_filestreams(ap, &args, &blen);
3759 		else
3760 			error = xfs_bmap_btalloc_nullfb(ap, &args, &blen);
3761 		if (error)
3762 			return error;
3763 	} else if (ap->dfops->dop_low) {
3764 		if (xfs_inode_is_filestream(ap->ip))
3765 			args.type = XFS_ALLOCTYPE_FIRST_AG;
3766 		else
3767 			args.type = XFS_ALLOCTYPE_START_BNO;
3768 		args.total = args.minlen = ap->minlen;
3769 	} else {
3770 		args.type = XFS_ALLOCTYPE_NEAR_BNO;
3771 		args.total = ap->total;
3772 		args.minlen = ap->minlen;
3773 	}
3774 	/* apply extent size hints if obtained earlier */
3775 	if (unlikely(align)) {
3776 		args.prod = align;
3777 		if ((args.mod = (xfs_extlen_t)do_mod(ap->offset, args.prod)))
3778 			args.mod = (xfs_extlen_t)(args.prod - args.mod);
3779 	} else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
3780 		args.prod = 1;
3781 		args.mod = 0;
3782 	} else {
3783 		args.prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
3784 		if ((args.mod = (xfs_extlen_t)(do_mod(ap->offset, args.prod))))
3785 			args.mod = (xfs_extlen_t)(args.prod - args.mod);
3786 	}
3787 	/*
3788 	 * If we are not low on available data blocks, and the
3789 	 * underlying logical volume manager is a stripe, and
3790 	 * the file offset is zero then try to allocate data
3791 	 * blocks on stripe unit boundary.
3792 	 * NOTE: ap->aeof is only set if the allocation length
3793 	 * is >= the stripe unit and the allocation offset is
3794 	 * at the end of file.
3795 	 */
3796 	if (!ap->dfops->dop_low && ap->aeof) {
3797 		if (!ap->offset) {
3798 			args.alignment = stripe_align;
3799 			atype = args.type;
3800 			isaligned = 1;
3801 			/*
3802 			 * Adjust for alignment
3803 			 */
3804 			if (blen > args.alignment && blen <= args.maxlen)
3805 				args.minlen = blen - args.alignment;
3806 			args.minalignslop = 0;
3807 		} else {
3808 			/*
3809 			 * First try an exact bno allocation.
3810 			 * If it fails then do a near or start bno
3811 			 * allocation with alignment turned on.
3812 			 */
3813 			atype = args.type;
3814 			tryagain = 1;
3815 			args.type = XFS_ALLOCTYPE_THIS_BNO;
3816 			args.alignment = 1;
3817 			/*
3818 			 * Compute the minlen+alignment for the
3819 			 * next case.  Set slop so that the value
3820 			 * of minlen+alignment+slop doesn't go up
3821 			 * between the calls.
3822 			 */
3823 			if (blen > stripe_align && blen <= args.maxlen)
3824 				nextminlen = blen - stripe_align;
3825 			else
3826 				nextminlen = args.minlen;
3827 			if (nextminlen + stripe_align > args.minlen + 1)
3828 				args.minalignslop =
3829 					nextminlen + stripe_align -
3830 					args.minlen - 1;
3831 			else
3832 				args.minalignslop = 0;
3833 		}
3834 	} else {
3835 		args.alignment = 1;
3836 		args.minalignslop = 0;
3837 	}
3838 	args.minleft = ap->minleft;
3839 	args.wasdel = ap->wasdel;
3840 	args.resv = XFS_AG_RESV_NONE;
3841 	args.datatype = ap->datatype;
3842 	if (ap->datatype & XFS_ALLOC_USERDATA_ZERO)
3843 		args.ip = ap->ip;
3844 
3845 	error = xfs_alloc_vextent(&args);
3846 	if (error)
3847 		return error;
3848 
3849 	if (tryagain && args.fsbno == NULLFSBLOCK) {
3850 		/*
3851 		 * Exact allocation failed. Now try with alignment
3852 		 * turned on.
3853 		 */
3854 		args.type = atype;
3855 		args.fsbno = ap->blkno;
3856 		args.alignment = stripe_align;
3857 		args.minlen = nextminlen;
3858 		args.minalignslop = 0;
3859 		isaligned = 1;
3860 		if ((error = xfs_alloc_vextent(&args)))
3861 			return error;
3862 	}
3863 	if (isaligned && args.fsbno == NULLFSBLOCK) {
3864 		/*
3865 		 * allocation failed, so turn off alignment and
3866 		 * try again.
3867 		 */
3868 		args.type = atype;
3869 		args.fsbno = ap->blkno;
3870 		args.alignment = 0;
3871 		if ((error = xfs_alloc_vextent(&args)))
3872 			return error;
3873 	}
3874 	if (args.fsbno == NULLFSBLOCK && nullfb &&
3875 	    args.minlen > ap->minlen) {
3876 		args.minlen = ap->minlen;
3877 		args.type = XFS_ALLOCTYPE_START_BNO;
3878 		args.fsbno = ap->blkno;
3879 		if ((error = xfs_alloc_vextent(&args)))
3880 			return error;
3881 	}
3882 	if (args.fsbno == NULLFSBLOCK && nullfb) {
3883 		args.fsbno = 0;
3884 		args.type = XFS_ALLOCTYPE_FIRST_AG;
3885 		args.total = ap->minlen;
3886 		args.minleft = 0;
3887 		if ((error = xfs_alloc_vextent(&args)))
3888 			return error;
3889 		ap->dfops->dop_low = true;
3890 	}
3891 	if (args.fsbno != NULLFSBLOCK) {
3892 		/*
3893 		 * check the allocation happened at the same or higher AG than
3894 		 * the first block that was allocated.
3895 		 */
3896 		ASSERT(*ap->firstblock == NULLFSBLOCK ||
3897 		       XFS_FSB_TO_AGNO(mp, *ap->firstblock) ==
3898 		       XFS_FSB_TO_AGNO(mp, args.fsbno) ||
3899 		       (ap->dfops->dop_low &&
3900 			XFS_FSB_TO_AGNO(mp, *ap->firstblock) <
3901 			XFS_FSB_TO_AGNO(mp, args.fsbno)));
3902 
3903 		ap->blkno = args.fsbno;
3904 		if (*ap->firstblock == NULLFSBLOCK)
3905 			*ap->firstblock = args.fsbno;
3906 		ASSERT(nullfb || fb_agno == args.agno ||
3907 		       (ap->dfops->dop_low && fb_agno < args.agno));
3908 		ap->length = args.len;
3909 		if (!(ap->flags & XFS_BMAPI_COWFORK))
3910 			ap->ip->i_d.di_nblocks += args.len;
3911 		xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
3912 		if (ap->wasdel)
3913 			ap->ip->i_delayed_blks -= args.len;
3914 		/*
3915 		 * Adjust the disk quota also. This was reserved
3916 		 * earlier.
3917 		 */
3918 		xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
3919 			ap->wasdel ? XFS_TRANS_DQ_DELBCOUNT :
3920 					XFS_TRANS_DQ_BCOUNT,
3921 			(long) args.len);
3922 	} else {
3923 		ap->blkno = NULLFSBLOCK;
3924 		ap->length = 0;
3925 	}
3926 	return 0;
3927 }
3928 
3929 /*
3930  * For a remap operation, just "allocate" an extent at the address that the
3931  * caller passed in, and ensure that the AGFL is the right size.  The caller
3932  * will then map the "allocated" extent into the file somewhere.
3933  */
3934 STATIC int
3935 xfs_bmap_remap_alloc(
3936 	struct xfs_bmalloca	*ap)
3937 {
3938 	struct xfs_trans	*tp = ap->tp;
3939 	struct xfs_mount	*mp = tp->t_mountp;
3940 	xfs_agblock_t		bno;
3941 	struct xfs_alloc_arg	args;
3942 	int			error;
3943 
3944 	/*
3945 	 * validate that the block number is legal - the enables us to detect
3946 	 * and handle a silent filesystem corruption rather than crashing.
3947 	 */
3948 	memset(&args, 0, sizeof(struct xfs_alloc_arg));
3949 	args.tp = ap->tp;
3950 	args.mp = ap->tp->t_mountp;
3951 	bno = *ap->firstblock;
3952 	args.agno = XFS_FSB_TO_AGNO(mp, bno);
3953 	args.agbno = XFS_FSB_TO_AGBNO(mp, bno);
3954 	if (args.agno >= mp->m_sb.sb_agcount ||
3955 	    args.agbno >= mp->m_sb.sb_agblocks)
3956 		return -EFSCORRUPTED;
3957 
3958 	/* "Allocate" the extent from the range we passed in. */
3959 	trace_xfs_bmap_remap_alloc(ap->ip, *ap->firstblock, ap->length);
3960 	ap->blkno = bno;
3961 	ap->ip->i_d.di_nblocks += ap->length;
3962 	xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
3963 
3964 	/* Fix the freelist, like a real allocator does. */
3965 	args.datatype = ap->datatype;
3966 	args.pag = xfs_perag_get(args.mp, args.agno);
3967 	ASSERT(args.pag);
3968 
3969 	/*
3970 	 * The freelist fixing code will decline the allocation if
3971 	 * the size and shape of the free space doesn't allow for
3972 	 * allocating the extent and updating all the metadata that
3973 	 * happens during an allocation.  We're remapping, not
3974 	 * allocating, so skip that check by pretending to be freeing.
3975 	 */
3976 	error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING);
3977 	xfs_perag_put(args.pag);
3978 	if (error)
3979 		trace_xfs_bmap_remap_alloc_error(ap->ip, error, _RET_IP_);
3980 	return error;
3981 }
3982 
3983 /*
3984  * xfs_bmap_alloc is called by xfs_bmapi to allocate an extent for a file.
3985  * It figures out where to ask the underlying allocator to put the new extent.
3986  */
3987 STATIC int
3988 xfs_bmap_alloc(
3989 	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3990 {
3991 	if (ap->flags & XFS_BMAPI_REMAP)
3992 		return xfs_bmap_remap_alloc(ap);
3993 	if (XFS_IS_REALTIME_INODE(ap->ip) &&
3994 	    xfs_alloc_is_userdata(ap->datatype))
3995 		return xfs_bmap_rtalloc(ap);
3996 	return xfs_bmap_btalloc(ap);
3997 }
3998 
3999 /* Trim extent to fit a logical block range. */
4000 void
4001 xfs_trim_extent(
4002 	struct xfs_bmbt_irec	*irec,
4003 	xfs_fileoff_t		bno,
4004 	xfs_filblks_t		len)
4005 {
4006 	xfs_fileoff_t		distance;
4007 	xfs_fileoff_t		end = bno + len;
4008 
4009 	if (irec->br_startoff + irec->br_blockcount <= bno ||
4010 	    irec->br_startoff >= end) {
4011 		irec->br_blockcount = 0;
4012 		return;
4013 	}
4014 
4015 	if (irec->br_startoff < bno) {
4016 		distance = bno - irec->br_startoff;
4017 		if (isnullstartblock(irec->br_startblock))
4018 			irec->br_startblock = DELAYSTARTBLOCK;
4019 		if (irec->br_startblock != DELAYSTARTBLOCK &&
4020 		    irec->br_startblock != HOLESTARTBLOCK)
4021 			irec->br_startblock += distance;
4022 		irec->br_startoff += distance;
4023 		irec->br_blockcount -= distance;
4024 	}
4025 
4026 	if (end < irec->br_startoff + irec->br_blockcount) {
4027 		distance = irec->br_startoff + irec->br_blockcount - end;
4028 		irec->br_blockcount -= distance;
4029 	}
4030 }
4031 
4032 /*
4033  * Trim the returned map to the required bounds
4034  */
4035 STATIC void
4036 xfs_bmapi_trim_map(
4037 	struct xfs_bmbt_irec	*mval,
4038 	struct xfs_bmbt_irec	*got,
4039 	xfs_fileoff_t		*bno,
4040 	xfs_filblks_t		len,
4041 	xfs_fileoff_t		obno,
4042 	xfs_fileoff_t		end,
4043 	int			n,
4044 	int			flags)
4045 {
4046 	if ((flags & XFS_BMAPI_ENTIRE) ||
4047 	    got->br_startoff + got->br_blockcount <= obno) {
4048 		*mval = *got;
4049 		if (isnullstartblock(got->br_startblock))
4050 			mval->br_startblock = DELAYSTARTBLOCK;
4051 		return;
4052 	}
4053 
4054 	if (obno > *bno)
4055 		*bno = obno;
4056 	ASSERT((*bno >= obno) || (n == 0));
4057 	ASSERT(*bno < end);
4058 	mval->br_startoff = *bno;
4059 	if (isnullstartblock(got->br_startblock))
4060 		mval->br_startblock = DELAYSTARTBLOCK;
4061 	else
4062 		mval->br_startblock = got->br_startblock +
4063 					(*bno - got->br_startoff);
4064 	/*
4065 	 * Return the minimum of what we got and what we asked for for
4066 	 * the length.  We can use the len variable here because it is
4067 	 * modified below and we could have been there before coming
4068 	 * here if the first part of the allocation didn't overlap what
4069 	 * was asked for.
4070 	 */
4071 	mval->br_blockcount = XFS_FILBLKS_MIN(end - *bno,
4072 			got->br_blockcount - (*bno - got->br_startoff));
4073 	mval->br_state = got->br_state;
4074 	ASSERT(mval->br_blockcount <= len);
4075 	return;
4076 }
4077 
4078 /*
4079  * Update and validate the extent map to return
4080  */
4081 STATIC void
4082 xfs_bmapi_update_map(
4083 	struct xfs_bmbt_irec	**map,
4084 	xfs_fileoff_t		*bno,
4085 	xfs_filblks_t		*len,
4086 	xfs_fileoff_t		obno,
4087 	xfs_fileoff_t		end,
4088 	int			*n,
4089 	int			flags)
4090 {
4091 	xfs_bmbt_irec_t	*mval = *map;
4092 
4093 	ASSERT((flags & XFS_BMAPI_ENTIRE) ||
4094 	       ((mval->br_startoff + mval->br_blockcount) <= end));
4095 	ASSERT((flags & XFS_BMAPI_ENTIRE) || (mval->br_blockcount <= *len) ||
4096 	       (mval->br_startoff < obno));
4097 
4098 	*bno = mval->br_startoff + mval->br_blockcount;
4099 	*len = end - *bno;
4100 	if (*n > 0 && mval->br_startoff == mval[-1].br_startoff) {
4101 		/* update previous map with new information */
4102 		ASSERT(mval->br_startblock == mval[-1].br_startblock);
4103 		ASSERT(mval->br_blockcount > mval[-1].br_blockcount);
4104 		ASSERT(mval->br_state == mval[-1].br_state);
4105 		mval[-1].br_blockcount = mval->br_blockcount;
4106 		mval[-1].br_state = mval->br_state;
4107 	} else if (*n > 0 && mval->br_startblock != DELAYSTARTBLOCK &&
4108 		   mval[-1].br_startblock != DELAYSTARTBLOCK &&
4109 		   mval[-1].br_startblock != HOLESTARTBLOCK &&
4110 		   mval->br_startblock == mval[-1].br_startblock +
4111 					  mval[-1].br_blockcount &&
4112 		   ((flags & XFS_BMAPI_IGSTATE) ||
4113 			mval[-1].br_state == mval->br_state)) {
4114 		ASSERT(mval->br_startoff ==
4115 		       mval[-1].br_startoff + mval[-1].br_blockcount);
4116 		mval[-1].br_blockcount += mval->br_blockcount;
4117 	} else if (*n > 0 &&
4118 		   mval->br_startblock == DELAYSTARTBLOCK &&
4119 		   mval[-1].br_startblock == DELAYSTARTBLOCK &&
4120 		   mval->br_startoff ==
4121 		   mval[-1].br_startoff + mval[-1].br_blockcount) {
4122 		mval[-1].br_blockcount += mval->br_blockcount;
4123 		mval[-1].br_state = mval->br_state;
4124 	} else if (!((*n == 0) &&
4125 		     ((mval->br_startoff + mval->br_blockcount) <=
4126 		      obno))) {
4127 		mval++;
4128 		(*n)++;
4129 	}
4130 	*map = mval;
4131 }
4132 
4133 /*
4134  * Map file blocks to filesystem blocks without allocation.
4135  */
4136 int
4137 xfs_bmapi_read(
4138 	struct xfs_inode	*ip,
4139 	xfs_fileoff_t		bno,
4140 	xfs_filblks_t		len,
4141 	struct xfs_bmbt_irec	*mval,
4142 	int			*nmap,
4143 	int			flags)
4144 {
4145 	struct xfs_mount	*mp = ip->i_mount;
4146 	struct xfs_ifork	*ifp;
4147 	struct xfs_bmbt_irec	got;
4148 	struct xfs_bmbt_irec	prev;
4149 	xfs_fileoff_t		obno;
4150 	xfs_fileoff_t		end;
4151 	xfs_extnum_t		lastx;
4152 	int			error;
4153 	int			eof;
4154 	int			n = 0;
4155 	int			whichfork = xfs_bmapi_whichfork(flags);
4156 
4157 	ASSERT(*nmap >= 1);
4158 	ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK|XFS_BMAPI_ENTIRE|
4159 			   XFS_BMAPI_IGSTATE|XFS_BMAPI_COWFORK)));
4160 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED|XFS_ILOCK_EXCL));
4161 
4162 	if (unlikely(XFS_TEST_ERROR(
4163 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
4164 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
4165 	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
4166 		XFS_ERROR_REPORT("xfs_bmapi_read", XFS_ERRLEVEL_LOW, mp);
4167 		return -EFSCORRUPTED;
4168 	}
4169 
4170 	if (XFS_FORCED_SHUTDOWN(mp))
4171 		return -EIO;
4172 
4173 	XFS_STATS_INC(mp, xs_blk_mapr);
4174 
4175 	ifp = XFS_IFORK_PTR(ip, whichfork);
4176 
4177 	/* No CoW fork?  Return a hole. */
4178 	if (whichfork == XFS_COW_FORK && !ifp) {
4179 		mval->br_startoff = bno;
4180 		mval->br_startblock = HOLESTARTBLOCK;
4181 		mval->br_blockcount = len;
4182 		mval->br_state = XFS_EXT_NORM;
4183 		*nmap = 1;
4184 		return 0;
4185 	}
4186 
4187 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
4188 		error = xfs_iread_extents(NULL, ip, whichfork);
4189 		if (error)
4190 			return error;
4191 	}
4192 
4193 	xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got, &prev);
4194 	end = bno + len;
4195 	obno = bno;
4196 
4197 	while (bno < end && n < *nmap) {
4198 		/* Reading past eof, act as though there's a hole up to end. */
4199 		if (eof)
4200 			got.br_startoff = end;
4201 		if (got.br_startoff > bno) {
4202 			/* Reading in a hole.  */
4203 			mval->br_startoff = bno;
4204 			mval->br_startblock = HOLESTARTBLOCK;
4205 			mval->br_blockcount =
4206 				XFS_FILBLKS_MIN(len, got.br_startoff - bno);
4207 			mval->br_state = XFS_EXT_NORM;
4208 			bno += mval->br_blockcount;
4209 			len -= mval->br_blockcount;
4210 			mval++;
4211 			n++;
4212 			continue;
4213 		}
4214 
4215 		/* set up the extent map to return. */
4216 		xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags);
4217 		xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
4218 
4219 		/* If we're done, stop now. */
4220 		if (bno >= end || n >= *nmap)
4221 			break;
4222 
4223 		/* Else go on to the next record. */
4224 		if (++lastx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t))
4225 			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx), &got);
4226 		else
4227 			eof = 1;
4228 	}
4229 	*nmap = n;
4230 	return 0;
4231 }
4232 
4233 int
4234 xfs_bmapi_reserve_delalloc(
4235 	struct xfs_inode	*ip,
4236 	int			whichfork,
4237 	xfs_fileoff_t		aoff,
4238 	xfs_filblks_t		len,
4239 	struct xfs_bmbt_irec	*got,
4240 	struct xfs_bmbt_irec	*prev,
4241 	xfs_extnum_t		*lastx,
4242 	int			eof)
4243 {
4244 	struct xfs_mount	*mp = ip->i_mount;
4245 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
4246 	xfs_extlen_t		alen;
4247 	xfs_extlen_t		indlen;
4248 	char			rt = XFS_IS_REALTIME_INODE(ip);
4249 	xfs_extlen_t		extsz;
4250 	int			error;
4251 
4252 	alen = XFS_FILBLKS_MIN(len, MAXEXTLEN);
4253 	if (!eof)
4254 		alen = XFS_FILBLKS_MIN(alen, got->br_startoff - aoff);
4255 
4256 	/* Figure out the extent size, adjust alen */
4257 	if (whichfork == XFS_COW_FORK)
4258 		extsz = xfs_get_cowextsz_hint(ip);
4259 	else
4260 		extsz = xfs_get_extsz_hint(ip);
4261 	if (extsz) {
4262 		error = xfs_bmap_extsize_align(mp, got, prev, extsz, rt, eof,
4263 					       1, 0, &aoff, &alen);
4264 		ASSERT(!error);
4265 	}
4266 
4267 	if (rt)
4268 		extsz = alen / mp->m_sb.sb_rextsize;
4269 
4270 	/*
4271 	 * Make a transaction-less quota reservation for delayed allocation
4272 	 * blocks.  This number gets adjusted later.  We return if we haven't
4273 	 * allocated blocks already inside this loop.
4274 	 */
4275 	error = xfs_trans_reserve_quota_nblks(NULL, ip, (long)alen, 0,
4276 			rt ? XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS);
4277 	if (error)
4278 		return error;
4279 
4280 	/*
4281 	 * Split changing sb for alen and indlen since they could be coming
4282 	 * from different places.
4283 	 */
4284 	indlen = (xfs_extlen_t)xfs_bmap_worst_indlen(ip, alen);
4285 	ASSERT(indlen > 0);
4286 
4287 	if (rt) {
4288 		error = xfs_mod_frextents(mp, -((int64_t)extsz));
4289 	} else {
4290 		error = xfs_mod_fdblocks(mp, -((int64_t)alen), false);
4291 	}
4292 
4293 	if (error)
4294 		goto out_unreserve_quota;
4295 
4296 	error = xfs_mod_fdblocks(mp, -((int64_t)indlen), false);
4297 	if (error)
4298 		goto out_unreserve_blocks;
4299 
4300 
4301 	ip->i_delayed_blks += alen;
4302 
4303 	got->br_startoff = aoff;
4304 	got->br_startblock = nullstartblock(indlen);
4305 	got->br_blockcount = alen;
4306 	got->br_state = XFS_EXT_NORM;
4307 	xfs_bmap_add_extent_hole_delay(ip, whichfork, lastx, got);
4308 
4309 	/*
4310 	 * Update our extent pointer, given that xfs_bmap_add_extent_hole_delay
4311 	 * might have merged it into one of the neighbouring ones.
4312 	 */
4313 	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *lastx), got);
4314 
4315 	ASSERT(got->br_startoff <= aoff);
4316 	ASSERT(got->br_startoff + got->br_blockcount >= aoff + alen);
4317 	ASSERT(isnullstartblock(got->br_startblock));
4318 	ASSERT(got->br_state == XFS_EXT_NORM);
4319 	return 0;
4320 
4321 out_unreserve_blocks:
4322 	if (rt)
4323 		xfs_mod_frextents(mp, extsz);
4324 	else
4325 		xfs_mod_fdblocks(mp, alen, false);
4326 out_unreserve_quota:
4327 	if (XFS_IS_QUOTA_ON(mp))
4328 		xfs_trans_unreserve_quota_nblks(NULL, ip, (long)alen, 0, rt ?
4329 				XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS);
4330 	return error;
4331 }
4332 
4333 static int
4334 xfs_bmapi_allocate(
4335 	struct xfs_bmalloca	*bma)
4336 {
4337 	struct xfs_mount	*mp = bma->ip->i_mount;
4338 	int			whichfork = xfs_bmapi_whichfork(bma->flags);
4339 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(bma->ip, whichfork);
4340 	int			tmp_logflags = 0;
4341 	int			error;
4342 
4343 	ASSERT(bma->length > 0);
4344 
4345 	/*
4346 	 * For the wasdelay case, we could also just allocate the stuff asked
4347 	 * for in this bmap call but that wouldn't be as good.
4348 	 */
4349 	if (bma->wasdel) {
4350 		bma->length = (xfs_extlen_t)bma->got.br_blockcount;
4351 		bma->offset = bma->got.br_startoff;
4352 		if (bma->idx != NULLEXTNUM && bma->idx) {
4353 			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx - 1),
4354 					 &bma->prev);
4355 		}
4356 	} else {
4357 		bma->length = XFS_FILBLKS_MIN(bma->length, MAXEXTLEN);
4358 		if (!bma->eof)
4359 			bma->length = XFS_FILBLKS_MIN(bma->length,
4360 					bma->got.br_startoff - bma->offset);
4361 	}
4362 
4363 	/*
4364 	 * Set the data type being allocated. For the data fork, the first data
4365 	 * in the file is treated differently to all other allocations. For the
4366 	 * attribute fork, we only need to ensure the allocated range is not on
4367 	 * the busy list.
4368 	 */
4369 	if (!(bma->flags & XFS_BMAPI_METADATA)) {
4370 		bma->datatype = XFS_ALLOC_NOBUSY;
4371 		if (whichfork == XFS_DATA_FORK) {
4372 			if (bma->offset == 0)
4373 				bma->datatype |= XFS_ALLOC_INITIAL_USER_DATA;
4374 			else
4375 				bma->datatype |= XFS_ALLOC_USERDATA;
4376 		}
4377 		if (bma->flags & XFS_BMAPI_ZERO)
4378 			bma->datatype |= XFS_ALLOC_USERDATA_ZERO;
4379 	}
4380 
4381 	bma->minlen = (bma->flags & XFS_BMAPI_CONTIG) ? bma->length : 1;
4382 
4383 	/*
4384 	 * Only want to do the alignment at the eof if it is userdata and
4385 	 * allocation length is larger than a stripe unit.
4386 	 */
4387 	if (mp->m_dalign && bma->length >= mp->m_dalign &&
4388 	    !(bma->flags & XFS_BMAPI_METADATA) && whichfork == XFS_DATA_FORK) {
4389 		error = xfs_bmap_isaeof(bma, whichfork);
4390 		if (error)
4391 			return error;
4392 	}
4393 
4394 	error = xfs_bmap_alloc(bma);
4395 	if (error)
4396 		return error;
4397 
4398 	if (bma->dfops->dop_low)
4399 		bma->minleft = 0;
4400 	if (bma->cur)
4401 		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4402 	if (bma->blkno == NULLFSBLOCK)
4403 		return 0;
4404 	if ((ifp->if_flags & XFS_IFBROOT) && !bma->cur) {
4405 		bma->cur = xfs_bmbt_init_cursor(mp, bma->tp, bma->ip, whichfork);
4406 		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4407 		bma->cur->bc_private.b.dfops = bma->dfops;
4408 	}
4409 	/*
4410 	 * Bump the number of extents we've allocated
4411 	 * in this call.
4412 	 */
4413 	bma->nallocs++;
4414 
4415 	if (bma->cur)
4416 		bma->cur->bc_private.b.flags =
4417 			bma->wasdel ? XFS_BTCUR_BPRV_WASDEL : 0;
4418 
4419 	bma->got.br_startoff = bma->offset;
4420 	bma->got.br_startblock = bma->blkno;
4421 	bma->got.br_blockcount = bma->length;
4422 	bma->got.br_state = XFS_EXT_NORM;
4423 
4424 	/*
4425 	 * A wasdelay extent has been initialized, so shouldn't be flagged
4426 	 * as unwritten.
4427 	 */
4428 	if (!bma->wasdel && (bma->flags & XFS_BMAPI_PREALLOC) &&
4429 	    xfs_sb_version_hasextflgbit(&mp->m_sb))
4430 		bma->got.br_state = XFS_EXT_UNWRITTEN;
4431 
4432 	if (bma->wasdel)
4433 		error = xfs_bmap_add_extent_delay_real(bma, whichfork);
4434 	else
4435 		error = xfs_bmap_add_extent_hole_real(bma, whichfork);
4436 
4437 	bma->logflags |= tmp_logflags;
4438 	if (error)
4439 		return error;
4440 
4441 	/*
4442 	 * Update our extent pointer, given that xfs_bmap_add_extent_delay_real
4443 	 * or xfs_bmap_add_extent_hole_real might have merged it into one of
4444 	 * the neighbouring ones.
4445 	 */
4446 	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx), &bma->got);
4447 
4448 	ASSERT(bma->got.br_startoff <= bma->offset);
4449 	ASSERT(bma->got.br_startoff + bma->got.br_blockcount >=
4450 	       bma->offset + bma->length);
4451 	ASSERT(bma->got.br_state == XFS_EXT_NORM ||
4452 	       bma->got.br_state == XFS_EXT_UNWRITTEN);
4453 	return 0;
4454 }
4455 
4456 STATIC int
4457 xfs_bmapi_convert_unwritten(
4458 	struct xfs_bmalloca	*bma,
4459 	struct xfs_bmbt_irec	*mval,
4460 	xfs_filblks_t		len,
4461 	int			flags)
4462 {
4463 	int			whichfork = xfs_bmapi_whichfork(flags);
4464 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(bma->ip, whichfork);
4465 	int			tmp_logflags = 0;
4466 	int			error;
4467 
4468 	/* check if we need to do unwritten->real conversion */
4469 	if (mval->br_state == XFS_EXT_UNWRITTEN &&
4470 	    (flags & XFS_BMAPI_PREALLOC))
4471 		return 0;
4472 
4473 	/* check if we need to do real->unwritten conversion */
4474 	if (mval->br_state == XFS_EXT_NORM &&
4475 	    (flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT)) !=
4476 			(XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT))
4477 		return 0;
4478 
4479 	ASSERT(whichfork != XFS_COW_FORK);
4480 
4481 	/*
4482 	 * Modify (by adding) the state flag, if writing.
4483 	 */
4484 	ASSERT(mval->br_blockcount <= len);
4485 	if ((ifp->if_flags & XFS_IFBROOT) && !bma->cur) {
4486 		bma->cur = xfs_bmbt_init_cursor(bma->ip->i_mount, bma->tp,
4487 					bma->ip, whichfork);
4488 		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4489 		bma->cur->bc_private.b.dfops = bma->dfops;
4490 	}
4491 	mval->br_state = (mval->br_state == XFS_EXT_UNWRITTEN)
4492 				? XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
4493 
4494 	/*
4495 	 * Before insertion into the bmbt, zero the range being converted
4496 	 * if required.
4497 	 */
4498 	if (flags & XFS_BMAPI_ZERO) {
4499 		error = xfs_zero_extent(bma->ip, mval->br_startblock,
4500 					mval->br_blockcount);
4501 		if (error)
4502 			return error;
4503 	}
4504 
4505 	error = xfs_bmap_add_extent_unwritten_real(bma->tp, bma->ip, &bma->idx,
4506 			&bma->cur, mval, bma->firstblock, bma->dfops,
4507 			&tmp_logflags);
4508 	/*
4509 	 * Log the inode core unconditionally in the unwritten extent conversion
4510 	 * path because the conversion might not have done so (e.g., if the
4511 	 * extent count hasn't changed). We need to make sure the inode is dirty
4512 	 * in the transaction for the sake of fsync(), even if nothing has
4513 	 * changed, because fsync() will not force the log for this transaction
4514 	 * unless it sees the inode pinned.
4515 	 */
4516 	bma->logflags |= tmp_logflags | XFS_ILOG_CORE;
4517 	if (error)
4518 		return error;
4519 
4520 	/*
4521 	 * Update our extent pointer, given that
4522 	 * xfs_bmap_add_extent_unwritten_real might have merged it into one
4523 	 * of the neighbouring ones.
4524 	 */
4525 	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx), &bma->got);
4526 
4527 	/*
4528 	 * We may have combined previously unwritten space with written space,
4529 	 * so generate another request.
4530 	 */
4531 	if (mval->br_blockcount < len)
4532 		return -EAGAIN;
4533 	return 0;
4534 }
4535 
4536 /*
4537  * Map file blocks to filesystem blocks, and allocate blocks or convert the
4538  * extent state if necessary.  Details behaviour is controlled by the flags
4539  * parameter.  Only allocates blocks from a single allocation group, to avoid
4540  * locking problems.
4541  *
4542  * The returned value in "firstblock" from the first call in a transaction
4543  * must be remembered and presented to subsequent calls in "firstblock".
4544  * An upper bound for the number of blocks to be allocated is supplied to
4545  * the first call in "total"; if no allocation group has that many free
4546  * blocks then the call will fail (return NULLFSBLOCK in "firstblock").
4547  */
4548 int
4549 xfs_bmapi_write(
4550 	struct xfs_trans	*tp,		/* transaction pointer */
4551 	struct xfs_inode	*ip,		/* incore inode */
4552 	xfs_fileoff_t		bno,		/* starting file offs. mapped */
4553 	xfs_filblks_t		len,		/* length to map in file */
4554 	int			flags,		/* XFS_BMAPI_... */
4555 	xfs_fsblock_t		*firstblock,	/* first allocated block
4556 						   controls a.g. for allocs */
4557 	xfs_extlen_t		total,		/* total blocks needed */
4558 	struct xfs_bmbt_irec	*mval,		/* output: map values */
4559 	int			*nmap,		/* i/o: mval size/count */
4560 	struct xfs_defer_ops	*dfops)		/* i/o: list extents to free */
4561 {
4562 	struct xfs_mount	*mp = ip->i_mount;
4563 	struct xfs_ifork	*ifp;
4564 	struct xfs_bmalloca	bma = { NULL };	/* args for xfs_bmap_alloc */
4565 	xfs_fileoff_t		end;		/* end of mapped file region */
4566 	int			eof;		/* after the end of extents */
4567 	int			error;		/* error return */
4568 	int			n;		/* current extent index */
4569 	xfs_fileoff_t		obno;		/* old block number (offset) */
4570 	int			whichfork;	/* data or attr fork */
4571 	char			inhole;		/* current location is hole in file */
4572 	char			wasdelay;	/* old extent was delayed */
4573 
4574 #ifdef DEBUG
4575 	xfs_fileoff_t		orig_bno;	/* original block number value */
4576 	int			orig_flags;	/* original flags arg value */
4577 	xfs_filblks_t		orig_len;	/* original value of len arg */
4578 	struct xfs_bmbt_irec	*orig_mval;	/* original value of mval */
4579 	int			orig_nmap;	/* original value of *nmap */
4580 
4581 	orig_bno = bno;
4582 	orig_len = len;
4583 	orig_flags = flags;
4584 	orig_mval = mval;
4585 	orig_nmap = *nmap;
4586 #endif
4587 	whichfork = xfs_bmapi_whichfork(flags);
4588 
4589 	ASSERT(*nmap >= 1);
4590 	ASSERT(*nmap <= XFS_BMAP_MAX_NMAP);
4591 	ASSERT(!(flags & XFS_BMAPI_IGSTATE));
4592 	ASSERT(tp != NULL);
4593 	ASSERT(len > 0);
4594 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL);
4595 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4596 	ASSERT(!(flags & XFS_BMAPI_REMAP) || whichfork == XFS_DATA_FORK);
4597 	ASSERT(!(flags & XFS_BMAPI_PREALLOC) || !(flags & XFS_BMAPI_REMAP));
4598 	ASSERT(!(flags & XFS_BMAPI_CONVERT) || !(flags & XFS_BMAPI_REMAP));
4599 	ASSERT(!(flags & XFS_BMAPI_PREALLOC) || whichfork != XFS_COW_FORK);
4600 	ASSERT(!(flags & XFS_BMAPI_CONVERT) || whichfork != XFS_COW_FORK);
4601 
4602 	/* zeroing is for currently only for data extents, not metadata */
4603 	ASSERT((flags & (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO)) !=
4604 			(XFS_BMAPI_METADATA | XFS_BMAPI_ZERO));
4605 	/*
4606 	 * we can allocate unwritten extents or pre-zero allocated blocks,
4607 	 * but it makes no sense to do both at once. This would result in
4608 	 * zeroing the unwritten extent twice, but it still being an
4609 	 * unwritten extent....
4610 	 */
4611 	ASSERT((flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO)) !=
4612 			(XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO));
4613 
4614 	if (unlikely(XFS_TEST_ERROR(
4615 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
4616 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
4617 	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
4618 		XFS_ERROR_REPORT("xfs_bmapi_write", XFS_ERRLEVEL_LOW, mp);
4619 		return -EFSCORRUPTED;
4620 	}
4621 
4622 	if (XFS_FORCED_SHUTDOWN(mp))
4623 		return -EIO;
4624 
4625 	ifp = XFS_IFORK_PTR(ip, whichfork);
4626 
4627 	XFS_STATS_INC(mp, xs_blk_mapw);
4628 
4629 	if (*firstblock == NULLFSBLOCK) {
4630 		if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE)
4631 			bma.minleft = be16_to_cpu(ifp->if_broot->bb_level) + 1;
4632 		else
4633 			bma.minleft = 1;
4634 	} else {
4635 		bma.minleft = 0;
4636 	}
4637 
4638 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
4639 		error = xfs_iread_extents(tp, ip, whichfork);
4640 		if (error)
4641 			goto error0;
4642 	}
4643 
4644 	xfs_bmap_search_extents(ip, bno, whichfork, &eof, &bma.idx, &bma.got,
4645 				&bma.prev);
4646 	n = 0;
4647 	end = bno + len;
4648 	obno = bno;
4649 
4650 	bma.tp = tp;
4651 	bma.ip = ip;
4652 	bma.total = total;
4653 	bma.datatype = 0;
4654 	bma.dfops = dfops;
4655 	bma.firstblock = firstblock;
4656 
4657 	while (bno < end && n < *nmap) {
4658 		inhole = eof || bma.got.br_startoff > bno;
4659 		wasdelay = !inhole && isnullstartblock(bma.got.br_startblock);
4660 
4661 		/*
4662 		 * Make sure we only reflink into a hole.
4663 		 */
4664 		if (flags & XFS_BMAPI_REMAP)
4665 			ASSERT(inhole);
4666 		if (flags & XFS_BMAPI_COWFORK)
4667 			ASSERT(!inhole);
4668 
4669 		/*
4670 		 * First, deal with the hole before the allocated space
4671 		 * that we found, if any.
4672 		 */
4673 		if (inhole || wasdelay) {
4674 			bma.eof = eof;
4675 			bma.conv = !!(flags & XFS_BMAPI_CONVERT);
4676 			bma.wasdel = wasdelay;
4677 			bma.offset = bno;
4678 			bma.flags = flags;
4679 
4680 			/*
4681 			 * There's a 32/64 bit type mismatch between the
4682 			 * allocation length request (which can be 64 bits in
4683 			 * length) and the bma length request, which is
4684 			 * xfs_extlen_t and therefore 32 bits. Hence we have to
4685 			 * check for 32-bit overflows and handle them here.
4686 			 */
4687 			if (len > (xfs_filblks_t)MAXEXTLEN)
4688 				bma.length = MAXEXTLEN;
4689 			else
4690 				bma.length = len;
4691 
4692 			ASSERT(len > 0);
4693 			ASSERT(bma.length > 0);
4694 			error = xfs_bmapi_allocate(&bma);
4695 			if (error)
4696 				goto error0;
4697 			if (bma.blkno == NULLFSBLOCK)
4698 				break;
4699 
4700 			/*
4701 			 * If this is a CoW allocation, record the data in
4702 			 * the refcount btree for orphan recovery.
4703 			 */
4704 			if (whichfork == XFS_COW_FORK) {
4705 				error = xfs_refcount_alloc_cow_extent(mp, dfops,
4706 						bma.blkno, bma.length);
4707 				if (error)
4708 					goto error0;
4709 			}
4710 		}
4711 
4712 		/* Deal with the allocated space we found.  */
4713 		xfs_bmapi_trim_map(mval, &bma.got, &bno, len, obno,
4714 							end, n, flags);
4715 
4716 		/* Execute unwritten extent conversion if necessary */
4717 		error = xfs_bmapi_convert_unwritten(&bma, mval, len, flags);
4718 		if (error == -EAGAIN)
4719 			continue;
4720 		if (error)
4721 			goto error0;
4722 
4723 		/* update the extent map to return */
4724 		xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
4725 
4726 		/*
4727 		 * If we're done, stop now.  Stop when we've allocated
4728 		 * XFS_BMAP_MAX_NMAP extents no matter what.  Otherwise
4729 		 * the transaction may get too big.
4730 		 */
4731 		if (bno >= end || n >= *nmap || bma.nallocs >= *nmap)
4732 			break;
4733 
4734 		/* Else go on to the next record. */
4735 		bma.prev = bma.got;
4736 		if (++bma.idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t)) {
4737 			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma.idx),
4738 					 &bma.got);
4739 		} else
4740 			eof = 1;
4741 	}
4742 	*nmap = n;
4743 
4744 	/*
4745 	 * Transform from btree to extents, give it cur.
4746 	 */
4747 	if (xfs_bmap_wants_extents(ip, whichfork)) {
4748 		int		tmp_logflags = 0;
4749 
4750 		ASSERT(bma.cur);
4751 		error = xfs_bmap_btree_to_extents(tp, ip, bma.cur,
4752 			&tmp_logflags, whichfork);
4753 		bma.logflags |= tmp_logflags;
4754 		if (error)
4755 			goto error0;
4756 	}
4757 
4758 	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE ||
4759 	       XFS_IFORK_NEXTENTS(ip, whichfork) >
4760 		XFS_IFORK_MAXEXT(ip, whichfork));
4761 	error = 0;
4762 error0:
4763 	/*
4764 	 * Log everything.  Do this after conversion, there's no point in
4765 	 * logging the extent records if we've converted to btree format.
4766 	 */
4767 	if ((bma.logflags & xfs_ilog_fext(whichfork)) &&
4768 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
4769 		bma.logflags &= ~xfs_ilog_fext(whichfork);
4770 	else if ((bma.logflags & xfs_ilog_fbroot(whichfork)) &&
4771 		 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
4772 		bma.logflags &= ~xfs_ilog_fbroot(whichfork);
4773 	/*
4774 	 * Log whatever the flags say, even if error.  Otherwise we might miss
4775 	 * detecting a case where the data is changed, there's an error,
4776 	 * and it's not logged so we don't shutdown when we should.
4777 	 */
4778 	if (bma.logflags)
4779 		xfs_trans_log_inode(tp, ip, bma.logflags);
4780 
4781 	if (bma.cur) {
4782 		if (!error) {
4783 			ASSERT(*firstblock == NULLFSBLOCK ||
4784 			       XFS_FSB_TO_AGNO(mp, *firstblock) ==
4785 			       XFS_FSB_TO_AGNO(mp,
4786 				       bma.cur->bc_private.b.firstblock) ||
4787 			       (dfops->dop_low &&
4788 				XFS_FSB_TO_AGNO(mp, *firstblock) <
4789 				XFS_FSB_TO_AGNO(mp,
4790 					bma.cur->bc_private.b.firstblock)));
4791 			*firstblock = bma.cur->bc_private.b.firstblock;
4792 		}
4793 		xfs_btree_del_cursor(bma.cur,
4794 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
4795 	}
4796 	if (!error)
4797 		xfs_bmap_validate_ret(orig_bno, orig_len, orig_flags, orig_mval,
4798 			orig_nmap, *nmap);
4799 	return error;
4800 }
4801 
4802 /*
4803  * When a delalloc extent is split (e.g., due to a hole punch), the original
4804  * indlen reservation must be shared across the two new extents that are left
4805  * behind.
4806  *
4807  * Given the original reservation and the worst case indlen for the two new
4808  * extents (as calculated by xfs_bmap_worst_indlen()), split the original
4809  * reservation fairly across the two new extents. If necessary, steal available
4810  * blocks from a deleted extent to make up a reservation deficiency (e.g., if
4811  * ores == 1). The number of stolen blocks is returned. The availability and
4812  * subsequent accounting of stolen blocks is the responsibility of the caller.
4813  */
4814 static xfs_filblks_t
4815 xfs_bmap_split_indlen(
4816 	xfs_filblks_t			ores,		/* original res. */
4817 	xfs_filblks_t			*indlen1,	/* ext1 worst indlen */
4818 	xfs_filblks_t			*indlen2,	/* ext2 worst indlen */
4819 	xfs_filblks_t			avail)		/* stealable blocks */
4820 {
4821 	xfs_filblks_t			len1 = *indlen1;
4822 	xfs_filblks_t			len2 = *indlen2;
4823 	xfs_filblks_t			nres = len1 + len2; /* new total res. */
4824 	xfs_filblks_t			stolen = 0;
4825 
4826 	/*
4827 	 * Steal as many blocks as we can to try and satisfy the worst case
4828 	 * indlen for both new extents.
4829 	 */
4830 	while (nres > ores && avail) {
4831 		nres--;
4832 		avail--;
4833 		stolen++;
4834 	}
4835 
4836 	/*
4837 	 * The only blocks available are those reserved for the original
4838 	 * extent and what we can steal from the extent being removed.
4839 	 * If this still isn't enough to satisfy the combined
4840 	 * requirements for the two new extents, skim blocks off of each
4841 	 * of the new reservations until they match what is available.
4842 	 */
4843 	while (nres > ores) {
4844 		if (len1) {
4845 			len1--;
4846 			nres--;
4847 		}
4848 		if (nres == ores)
4849 			break;
4850 		if (len2) {
4851 			len2--;
4852 			nres--;
4853 		}
4854 	}
4855 
4856 	*indlen1 = len1;
4857 	*indlen2 = len2;
4858 
4859 	return stolen;
4860 }
4861 
4862 int
4863 xfs_bmap_del_extent_delay(
4864 	struct xfs_inode	*ip,
4865 	int			whichfork,
4866 	xfs_extnum_t		*idx,
4867 	struct xfs_bmbt_irec	*got,
4868 	struct xfs_bmbt_irec	*del)
4869 {
4870 	struct xfs_mount	*mp = ip->i_mount;
4871 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
4872 	struct xfs_bmbt_irec	new;
4873 	int64_t			da_old, da_new, da_diff = 0;
4874 	xfs_fileoff_t		del_endoff, got_endoff;
4875 	xfs_filblks_t		got_indlen, new_indlen, stolen;
4876 	int			error = 0, state = 0;
4877 	bool			isrt;
4878 
4879 	XFS_STATS_INC(mp, xs_del_exlist);
4880 
4881 	isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
4882 	del_endoff = del->br_startoff + del->br_blockcount;
4883 	got_endoff = got->br_startoff + got->br_blockcount;
4884 	da_old = startblockval(got->br_startblock);
4885 	da_new = 0;
4886 
4887 	ASSERT(*idx >= 0);
4888 	ASSERT(*idx < ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
4889 	ASSERT(del->br_blockcount > 0);
4890 	ASSERT(got->br_startoff <= del->br_startoff);
4891 	ASSERT(got_endoff >= del_endoff);
4892 
4893 	if (isrt) {
4894 		int64_t rtexts = XFS_FSB_TO_B(mp, del->br_blockcount);
4895 
4896 		do_div(rtexts, mp->m_sb.sb_rextsize);
4897 		xfs_mod_frextents(mp, rtexts);
4898 	}
4899 
4900 	/*
4901 	 * Update the inode delalloc counter now and wait to update the
4902 	 * sb counters as we might have to borrow some blocks for the
4903 	 * indirect block accounting.
4904 	 */
4905 	xfs_trans_reserve_quota_nblks(NULL, ip, -((long)del->br_blockcount), 0,
4906 			isrt ? XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS);
4907 	ip->i_delayed_blks -= del->br_blockcount;
4908 
4909 	if (whichfork == XFS_COW_FORK)
4910 		state |= BMAP_COWFORK;
4911 
4912 	if (got->br_startoff == del->br_startoff)
4913 		state |= BMAP_LEFT_CONTIG;
4914 	if (got_endoff == del_endoff)
4915 		state |= BMAP_RIGHT_CONTIG;
4916 
4917 	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
4918 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
4919 		/*
4920 		 * Matches the whole extent.  Delete the entry.
4921 		 */
4922 		xfs_iext_remove(ip, *idx, 1, state);
4923 		--*idx;
4924 		break;
4925 	case BMAP_LEFT_CONTIG:
4926 		/*
4927 		 * Deleting the first part of the extent.
4928 		 */
4929 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
4930 		got->br_startoff = del_endoff;
4931 		got->br_blockcount -= del->br_blockcount;
4932 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4933 				got->br_blockcount), da_old);
4934 		got->br_startblock = nullstartblock((int)da_new);
4935 		xfs_bmbt_set_all(xfs_iext_get_ext(ifp, *idx), got);
4936 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
4937 		break;
4938 	case BMAP_RIGHT_CONTIG:
4939 		/*
4940 		 * Deleting the last part of the extent.
4941 		 */
4942 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
4943 		got->br_blockcount = got->br_blockcount - del->br_blockcount;
4944 		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4945 				got->br_blockcount), da_old);
4946 		got->br_startblock = nullstartblock((int)da_new);
4947 		xfs_bmbt_set_all(xfs_iext_get_ext(ifp, *idx), got);
4948 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
4949 		break;
4950 	case 0:
4951 		/*
4952 		 * Deleting the middle of the extent.
4953 		 *
4954 		 * Distribute the original indlen reservation across the two new
4955 		 * extents.  Steal blocks from the deleted extent if necessary.
4956 		 * Stealing blocks simply fudges the fdblocks accounting below.
4957 		 * Warn if either of the new indlen reservations is zero as this
4958 		 * can lead to delalloc problems.
4959 		 */
4960 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
4961 
4962 		got->br_blockcount = del->br_startoff - got->br_startoff;
4963 		got_indlen = xfs_bmap_worst_indlen(ip, got->br_blockcount);
4964 
4965 		new.br_blockcount = got_endoff - del_endoff;
4966 		new_indlen = xfs_bmap_worst_indlen(ip, new.br_blockcount);
4967 
4968 		WARN_ON_ONCE(!got_indlen || !new_indlen);
4969 		stolen = xfs_bmap_split_indlen(da_old, &got_indlen, &new_indlen,
4970 						       del->br_blockcount);
4971 
4972 		got->br_startblock = nullstartblock((int)got_indlen);
4973 		xfs_bmbt_set_all(xfs_iext_get_ext(ifp, *idx), got);
4974 		trace_xfs_bmap_post_update(ip, *idx, 0, _THIS_IP_);
4975 
4976 		new.br_startoff = del_endoff;
4977 		new.br_state = got->br_state;
4978 		new.br_startblock = nullstartblock((int)new_indlen);
4979 
4980 		++*idx;
4981 		xfs_iext_insert(ip, *idx, 1, &new, state);
4982 
4983 		da_new = got_indlen + new_indlen - stolen;
4984 		del->br_blockcount -= stolen;
4985 		break;
4986 	}
4987 
4988 	ASSERT(da_old >= da_new);
4989 	da_diff = da_old - da_new;
4990 	if (!isrt)
4991 		da_diff += del->br_blockcount;
4992 	if (da_diff)
4993 		xfs_mod_fdblocks(mp, da_diff, false);
4994 	return error;
4995 }
4996 
4997 void
4998 xfs_bmap_del_extent_cow(
4999 	struct xfs_inode	*ip,
5000 	xfs_extnum_t		*idx,
5001 	struct xfs_bmbt_irec	*got,
5002 	struct xfs_bmbt_irec	*del)
5003 {
5004 	struct xfs_mount	*mp = ip->i_mount;
5005 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
5006 	struct xfs_bmbt_irec	new;
5007 	xfs_fileoff_t		del_endoff, got_endoff;
5008 	int			state = BMAP_COWFORK;
5009 
5010 	XFS_STATS_INC(mp, xs_del_exlist);
5011 
5012 	del_endoff = del->br_startoff + del->br_blockcount;
5013 	got_endoff = got->br_startoff + got->br_blockcount;
5014 
5015 	ASSERT(*idx >= 0);
5016 	ASSERT(*idx < ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
5017 	ASSERT(del->br_blockcount > 0);
5018 	ASSERT(got->br_startoff <= del->br_startoff);
5019 	ASSERT(got_endoff >= del_endoff);
5020 	ASSERT(!isnullstartblock(got->br_startblock));
5021 
5022 	if (got->br_startoff == del->br_startoff)
5023 		state |= BMAP_LEFT_CONTIG;
5024 	if (got_endoff == del_endoff)
5025 		state |= BMAP_RIGHT_CONTIG;
5026 
5027 	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
5028 	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
5029 		/*
5030 		 * Matches the whole extent.  Delete the entry.
5031 		 */
5032 		xfs_iext_remove(ip, *idx, 1, state);
5033 		--*idx;
5034 		break;
5035 	case BMAP_LEFT_CONTIG:
5036 		/*
5037 		 * Deleting the first part of the extent.
5038 		 */
5039 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
5040 		got->br_startoff = del_endoff;
5041 		got->br_blockcount -= del->br_blockcount;
5042 		got->br_startblock = del->br_startblock + del->br_blockcount;
5043 		xfs_bmbt_set_all(xfs_iext_get_ext(ifp, *idx), got);
5044 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5045 		break;
5046 	case BMAP_RIGHT_CONTIG:
5047 		/*
5048 		 * Deleting the last part of the extent.
5049 		 */
5050 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
5051 		got->br_blockcount -= del->br_blockcount;
5052 		xfs_bmbt_set_all(xfs_iext_get_ext(ifp, *idx), got);
5053 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5054 		break;
5055 	case 0:
5056 		/*
5057 		 * Deleting the middle of the extent.
5058 		 */
5059 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
5060 		got->br_blockcount = del->br_startoff - got->br_startoff;
5061 		xfs_bmbt_set_all(xfs_iext_get_ext(ifp, *idx), got);
5062 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5063 
5064 		new.br_startoff = del_endoff;
5065 		new.br_blockcount = got_endoff - del_endoff;
5066 		new.br_state = got->br_state;
5067 		new.br_startblock = del->br_startblock + del->br_blockcount;
5068 
5069 		++*idx;
5070 		xfs_iext_insert(ip, *idx, 1, &new, state);
5071 		break;
5072 	}
5073 }
5074 
5075 /*
5076  * Called by xfs_bmapi to update file extent records and the btree
5077  * after removing space (or undoing a delayed allocation).
5078  */
5079 STATIC int				/* error */
5080 xfs_bmap_del_extent(
5081 	xfs_inode_t		*ip,	/* incore inode pointer */
5082 	xfs_trans_t		*tp,	/* current transaction pointer */
5083 	xfs_extnum_t		*idx,	/* extent number to update/delete */
5084 	struct xfs_defer_ops	*dfops,	/* list of extents to be freed */
5085 	xfs_btree_cur_t		*cur,	/* if null, not a btree */
5086 	xfs_bmbt_irec_t		*del,	/* data to remove from extents */
5087 	int			*logflagsp, /* inode logging flags */
5088 	int			whichfork, /* data or attr fork */
5089 	int			bflags)	/* bmapi flags */
5090 {
5091 	xfs_filblks_t		da_new;	/* new delay-alloc indirect blocks */
5092 	xfs_filblks_t		da_old;	/* old delay-alloc indirect blocks */
5093 	xfs_fsblock_t		del_endblock=0;	/* first block past del */
5094 	xfs_fileoff_t		del_endoff;	/* first offset past del */
5095 	int			delay;	/* current block is delayed allocated */
5096 	int			do_fx;	/* free extent at end of routine */
5097 	xfs_bmbt_rec_host_t	*ep;	/* current extent entry pointer */
5098 	int			error;	/* error return value */
5099 	int			flags;	/* inode logging flags */
5100 	xfs_bmbt_irec_t		got;	/* current extent entry */
5101 	xfs_fileoff_t		got_endoff;	/* first offset past got */
5102 	int			i;	/* temp state */
5103 	xfs_ifork_t		*ifp;	/* inode fork pointer */
5104 	xfs_mount_t		*mp;	/* mount structure */
5105 	xfs_filblks_t		nblks;	/* quota/sb block count */
5106 	xfs_bmbt_irec_t		new;	/* new record to be inserted */
5107 	/* REFERENCED */
5108 	uint			qfield;	/* quota field to update */
5109 	xfs_filblks_t		temp;	/* for indirect length calculations */
5110 	xfs_filblks_t		temp2;	/* for indirect length calculations */
5111 	int			state = 0;
5112 
5113 	mp = ip->i_mount;
5114 	XFS_STATS_INC(mp, xs_del_exlist);
5115 
5116 	if (whichfork == XFS_ATTR_FORK)
5117 		state |= BMAP_ATTRFORK;
5118 	else if (whichfork == XFS_COW_FORK)
5119 		state |= BMAP_COWFORK;
5120 
5121 	ifp = XFS_IFORK_PTR(ip, whichfork);
5122 	ASSERT((*idx >= 0) && (*idx < ifp->if_bytes /
5123 		(uint)sizeof(xfs_bmbt_rec_t)));
5124 	ASSERT(del->br_blockcount > 0);
5125 	ep = xfs_iext_get_ext(ifp, *idx);
5126 	xfs_bmbt_get_all(ep, &got);
5127 	ASSERT(got.br_startoff <= del->br_startoff);
5128 	del_endoff = del->br_startoff + del->br_blockcount;
5129 	got_endoff = got.br_startoff + got.br_blockcount;
5130 	ASSERT(got_endoff >= del_endoff);
5131 	delay = isnullstartblock(got.br_startblock);
5132 	ASSERT(isnullstartblock(del->br_startblock) == delay);
5133 	flags = 0;
5134 	qfield = 0;
5135 	error = 0;
5136 	/*
5137 	 * If deleting a real allocation, must free up the disk space.
5138 	 */
5139 	if (!delay) {
5140 		flags = XFS_ILOG_CORE;
5141 		/*
5142 		 * Realtime allocation.  Free it and record di_nblocks update.
5143 		 */
5144 		if (whichfork == XFS_DATA_FORK && XFS_IS_REALTIME_INODE(ip)) {
5145 			xfs_fsblock_t	bno;
5146 			xfs_filblks_t	len;
5147 
5148 			ASSERT(do_mod(del->br_blockcount,
5149 				      mp->m_sb.sb_rextsize) == 0);
5150 			ASSERT(do_mod(del->br_startblock,
5151 				      mp->m_sb.sb_rextsize) == 0);
5152 			bno = del->br_startblock;
5153 			len = del->br_blockcount;
5154 			do_div(bno, mp->m_sb.sb_rextsize);
5155 			do_div(len, mp->m_sb.sb_rextsize);
5156 			error = xfs_rtfree_extent(tp, bno, (xfs_extlen_t)len);
5157 			if (error)
5158 				goto done;
5159 			do_fx = 0;
5160 			nblks = len * mp->m_sb.sb_rextsize;
5161 			qfield = XFS_TRANS_DQ_RTBCOUNT;
5162 		}
5163 		/*
5164 		 * Ordinary allocation.
5165 		 */
5166 		else {
5167 			do_fx = 1;
5168 			nblks = del->br_blockcount;
5169 			qfield = XFS_TRANS_DQ_BCOUNT;
5170 		}
5171 		/*
5172 		 * Set up del_endblock and cur for later.
5173 		 */
5174 		del_endblock = del->br_startblock + del->br_blockcount;
5175 		if (cur) {
5176 			if ((error = xfs_bmbt_lookup_eq(cur, got.br_startoff,
5177 					got.br_startblock, got.br_blockcount,
5178 					&i)))
5179 				goto done;
5180 			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
5181 		}
5182 		da_old = da_new = 0;
5183 	} else {
5184 		da_old = startblockval(got.br_startblock);
5185 		da_new = 0;
5186 		nblks = 0;
5187 		do_fx = 0;
5188 	}
5189 
5190 	/*
5191 	 * Set flag value to use in switch statement.
5192 	 * Left-contig is 2, right-contig is 1.
5193 	 */
5194 	switch (((got.br_startoff == del->br_startoff) << 1) |
5195 		(got_endoff == del_endoff)) {
5196 	case 3:
5197 		/*
5198 		 * Matches the whole extent.  Delete the entry.
5199 		 */
5200 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
5201 		xfs_iext_remove(ip, *idx, 1,
5202 				whichfork == XFS_ATTR_FORK ? BMAP_ATTRFORK : 0);
5203 		--*idx;
5204 		if (delay)
5205 			break;
5206 
5207 		XFS_IFORK_NEXT_SET(ip, whichfork,
5208 			XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
5209 		flags |= XFS_ILOG_CORE;
5210 		if (!cur) {
5211 			flags |= xfs_ilog_fext(whichfork);
5212 			break;
5213 		}
5214 		if ((error = xfs_btree_delete(cur, &i)))
5215 			goto done;
5216 		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
5217 		break;
5218 
5219 	case 2:
5220 		/*
5221 		 * Deleting the first part of the extent.
5222 		 */
5223 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
5224 		xfs_bmbt_set_startoff(ep, del_endoff);
5225 		temp = got.br_blockcount - del->br_blockcount;
5226 		xfs_bmbt_set_blockcount(ep, temp);
5227 		if (delay) {
5228 			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
5229 				da_old);
5230 			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
5231 			trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5232 			da_new = temp;
5233 			break;
5234 		}
5235 		xfs_bmbt_set_startblock(ep, del_endblock);
5236 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5237 		if (!cur) {
5238 			flags |= xfs_ilog_fext(whichfork);
5239 			break;
5240 		}
5241 		if ((error = xfs_bmbt_update(cur, del_endoff, del_endblock,
5242 				got.br_blockcount - del->br_blockcount,
5243 				got.br_state)))
5244 			goto done;
5245 		break;
5246 
5247 	case 1:
5248 		/*
5249 		 * Deleting the last part of the extent.
5250 		 */
5251 		temp = got.br_blockcount - del->br_blockcount;
5252 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
5253 		xfs_bmbt_set_blockcount(ep, temp);
5254 		if (delay) {
5255 			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
5256 				da_old);
5257 			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
5258 			trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5259 			da_new = temp;
5260 			break;
5261 		}
5262 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5263 		if (!cur) {
5264 			flags |= xfs_ilog_fext(whichfork);
5265 			break;
5266 		}
5267 		if ((error = xfs_bmbt_update(cur, got.br_startoff,
5268 				got.br_startblock,
5269 				got.br_blockcount - del->br_blockcount,
5270 				got.br_state)))
5271 			goto done;
5272 		break;
5273 
5274 	case 0:
5275 		/*
5276 		 * Deleting the middle of the extent.
5277 		 */
5278 		temp = del->br_startoff - got.br_startoff;
5279 		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
5280 		xfs_bmbt_set_blockcount(ep, temp);
5281 		new.br_startoff = del_endoff;
5282 		temp2 = got_endoff - del_endoff;
5283 		new.br_blockcount = temp2;
5284 		new.br_state = got.br_state;
5285 		if (!delay) {
5286 			new.br_startblock = del_endblock;
5287 			flags |= XFS_ILOG_CORE;
5288 			if (cur) {
5289 				if ((error = xfs_bmbt_update(cur,
5290 						got.br_startoff,
5291 						got.br_startblock, temp,
5292 						got.br_state)))
5293 					goto done;
5294 				if ((error = xfs_btree_increment(cur, 0, &i)))
5295 					goto done;
5296 				cur->bc_rec.b = new;
5297 				error = xfs_btree_insert(cur, &i);
5298 				if (error && error != -ENOSPC)
5299 					goto done;
5300 				/*
5301 				 * If get no-space back from btree insert,
5302 				 * it tried a split, and we have a zero
5303 				 * block reservation.
5304 				 * Fix up our state and return the error.
5305 				 */
5306 				if (error == -ENOSPC) {
5307 					/*
5308 					 * Reset the cursor, don't trust
5309 					 * it after any insert operation.
5310 					 */
5311 					if ((error = xfs_bmbt_lookup_eq(cur,
5312 							got.br_startoff,
5313 							got.br_startblock,
5314 							temp, &i)))
5315 						goto done;
5316 					XFS_WANT_CORRUPTED_GOTO(mp,
5317 								i == 1, done);
5318 					/*
5319 					 * Update the btree record back
5320 					 * to the original value.
5321 					 */
5322 					if ((error = xfs_bmbt_update(cur,
5323 							got.br_startoff,
5324 							got.br_startblock,
5325 							got.br_blockcount,
5326 							got.br_state)))
5327 						goto done;
5328 					/*
5329 					 * Reset the extent record back
5330 					 * to the original value.
5331 					 */
5332 					xfs_bmbt_set_blockcount(ep,
5333 						got.br_blockcount);
5334 					flags = 0;
5335 					error = -ENOSPC;
5336 					goto done;
5337 				}
5338 				XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
5339 			} else
5340 				flags |= xfs_ilog_fext(whichfork);
5341 			XFS_IFORK_NEXT_SET(ip, whichfork,
5342 				XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
5343 		} else {
5344 			xfs_filblks_t	stolen;
5345 			ASSERT(whichfork == XFS_DATA_FORK);
5346 
5347 			/*
5348 			 * Distribute the original indlen reservation across the
5349 			 * two new extents. Steal blocks from the deleted extent
5350 			 * if necessary. Stealing blocks simply fudges the
5351 			 * fdblocks accounting in xfs_bunmapi().
5352 			 */
5353 			temp = xfs_bmap_worst_indlen(ip, got.br_blockcount);
5354 			temp2 = xfs_bmap_worst_indlen(ip, new.br_blockcount);
5355 			stolen = xfs_bmap_split_indlen(da_old, &temp, &temp2,
5356 						       del->br_blockcount);
5357 			da_new = temp + temp2 - stolen;
5358 			del->br_blockcount -= stolen;
5359 
5360 			/*
5361 			 * Set the reservation for each extent. Warn if either
5362 			 * is zero as this can lead to delalloc problems.
5363 			 */
5364 			WARN_ON_ONCE(!temp || !temp2);
5365 			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
5366 			new.br_startblock = nullstartblock((int)temp2);
5367 		}
5368 		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
5369 		xfs_iext_insert(ip, *idx + 1, 1, &new, state);
5370 		++*idx;
5371 		break;
5372 	}
5373 
5374 	/* remove reverse mapping */
5375 	if (!delay) {
5376 		error = xfs_rmap_unmap_extent(mp, dfops, ip, whichfork, del);
5377 		if (error)
5378 			goto done;
5379 	}
5380 
5381 	/*
5382 	 * If we need to, add to list of extents to delete.
5383 	 */
5384 	if (do_fx && !(bflags & XFS_BMAPI_REMAP)) {
5385 		if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) {
5386 			error = xfs_refcount_decrease_extent(mp, dfops, del);
5387 			if (error)
5388 				goto done;
5389 		} else
5390 			xfs_bmap_add_free(mp, dfops, del->br_startblock,
5391 					del->br_blockcount, NULL);
5392 	}
5393 
5394 	/*
5395 	 * Adjust inode # blocks in the file.
5396 	 */
5397 	if (nblks)
5398 		ip->i_d.di_nblocks -= nblks;
5399 	/*
5400 	 * Adjust quota data.
5401 	 */
5402 	if (qfield && !(bflags & XFS_BMAPI_REMAP))
5403 		xfs_trans_mod_dquot_byino(tp, ip, qfield, (long)-nblks);
5404 
5405 	/*
5406 	 * Account for change in delayed indirect blocks.
5407 	 * Nothing to do for disk quota accounting here.
5408 	 */
5409 	ASSERT(da_old >= da_new);
5410 	if (da_old > da_new)
5411 		xfs_mod_fdblocks(mp, (int64_t)(da_old - da_new), false);
5412 done:
5413 	*logflagsp = flags;
5414 	return error;
5415 }
5416 
5417 /*
5418  * Unmap (remove) blocks from a file.
5419  * If nexts is nonzero then the number of extents to remove is limited to
5420  * that value.  If not all extents in the block range can be removed then
5421  * *done is set.
5422  */
5423 int						/* error */
5424 __xfs_bunmapi(
5425 	xfs_trans_t		*tp,		/* transaction pointer */
5426 	struct xfs_inode	*ip,		/* incore inode */
5427 	xfs_fileoff_t		bno,		/* starting offset to unmap */
5428 	xfs_filblks_t		*rlen,		/* i/o: amount remaining */
5429 	int			flags,		/* misc flags */
5430 	xfs_extnum_t		nexts,		/* number of extents max */
5431 	xfs_fsblock_t		*firstblock,	/* first allocated block
5432 						   controls a.g. for allocs */
5433 	struct xfs_defer_ops	*dfops)		/* i/o: deferred updates */
5434 {
5435 	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
5436 	xfs_bmbt_irec_t		del;		/* extent being deleted */
5437 	int			eof;		/* is deleting at eof */
5438 	xfs_bmbt_rec_host_t	*ep;		/* extent record pointer */
5439 	int			error;		/* error return value */
5440 	xfs_extnum_t		extno;		/* extent number in list */
5441 	xfs_bmbt_irec_t		got;		/* current extent record */
5442 	xfs_ifork_t		*ifp;		/* inode fork pointer */
5443 	int			isrt;		/* freeing in rt area */
5444 	xfs_extnum_t		lastx;		/* last extent index used */
5445 	int			logflags;	/* transaction logging flags */
5446 	xfs_extlen_t		mod;		/* rt extent offset */
5447 	xfs_mount_t		*mp;		/* mount structure */
5448 	xfs_extnum_t		nextents;	/* number of file extents */
5449 	xfs_bmbt_irec_t		prev;		/* previous extent record */
5450 	xfs_fileoff_t		start;		/* first file offset deleted */
5451 	int			tmp_logflags;	/* partial logging flags */
5452 	int			wasdel;		/* was a delayed alloc extent */
5453 	int			whichfork;	/* data or attribute fork */
5454 	xfs_fsblock_t		sum;
5455 	xfs_filblks_t		len = *rlen;	/* length to unmap in file */
5456 
5457 	trace_xfs_bunmap(ip, bno, len, flags, _RET_IP_);
5458 
5459 	whichfork = xfs_bmapi_whichfork(flags);
5460 	ASSERT(whichfork != XFS_COW_FORK);
5461 	ifp = XFS_IFORK_PTR(ip, whichfork);
5462 	if (unlikely(
5463 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
5464 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
5465 		XFS_ERROR_REPORT("xfs_bunmapi", XFS_ERRLEVEL_LOW,
5466 				 ip->i_mount);
5467 		return -EFSCORRUPTED;
5468 	}
5469 	mp = ip->i_mount;
5470 	if (XFS_FORCED_SHUTDOWN(mp))
5471 		return -EIO;
5472 
5473 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5474 	ASSERT(len > 0);
5475 	ASSERT(nexts >= 0);
5476 
5477 	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
5478 	    (error = xfs_iread_extents(tp, ip, whichfork)))
5479 		return error;
5480 	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
5481 	if (nextents == 0) {
5482 		*rlen = 0;
5483 		return 0;
5484 	}
5485 	XFS_STATS_INC(mp, xs_blk_unmap);
5486 	isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
5487 	start = bno;
5488 	bno = start + len - 1;
5489 	ep = xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
5490 		&prev);
5491 
5492 	/*
5493 	 * Check to see if the given block number is past the end of the
5494 	 * file, back up to the last block if so...
5495 	 */
5496 	if (eof) {
5497 		ep = xfs_iext_get_ext(ifp, --lastx);
5498 		xfs_bmbt_get_all(ep, &got);
5499 		bno = got.br_startoff + got.br_blockcount - 1;
5500 	}
5501 	logflags = 0;
5502 	if (ifp->if_flags & XFS_IFBROOT) {
5503 		ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
5504 		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5505 		cur->bc_private.b.firstblock = *firstblock;
5506 		cur->bc_private.b.dfops = dfops;
5507 		cur->bc_private.b.flags = 0;
5508 	} else
5509 		cur = NULL;
5510 
5511 	if (isrt) {
5512 		/*
5513 		 * Synchronize by locking the bitmap inode.
5514 		 */
5515 		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
5516 		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
5517 		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
5518 		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
5519 	}
5520 
5521 	extno = 0;
5522 	while (bno != (xfs_fileoff_t)-1 && bno >= start && lastx >= 0 &&
5523 	       (nexts == 0 || extno < nexts)) {
5524 		/*
5525 		 * Is the found extent after a hole in which bno lives?
5526 		 * Just back up to the previous extent, if so.
5527 		 */
5528 		if (got.br_startoff > bno) {
5529 			if (--lastx < 0)
5530 				break;
5531 			ep = xfs_iext_get_ext(ifp, lastx);
5532 			xfs_bmbt_get_all(ep, &got);
5533 		}
5534 		/*
5535 		 * Is the last block of this extent before the range
5536 		 * we're supposed to delete?  If so, we're done.
5537 		 */
5538 		bno = XFS_FILEOFF_MIN(bno,
5539 			got.br_startoff + got.br_blockcount - 1);
5540 		if (bno < start)
5541 			break;
5542 		/*
5543 		 * Then deal with the (possibly delayed) allocated space
5544 		 * we found.
5545 		 */
5546 		ASSERT(ep != NULL);
5547 		del = got;
5548 		wasdel = isnullstartblock(del.br_startblock);
5549 		if (got.br_startoff < start) {
5550 			del.br_startoff = start;
5551 			del.br_blockcount -= start - got.br_startoff;
5552 			if (!wasdel)
5553 				del.br_startblock += start - got.br_startoff;
5554 		}
5555 		if (del.br_startoff + del.br_blockcount > bno + 1)
5556 			del.br_blockcount = bno + 1 - del.br_startoff;
5557 		sum = del.br_startblock + del.br_blockcount;
5558 		if (isrt &&
5559 		    (mod = do_mod(sum, mp->m_sb.sb_rextsize))) {
5560 			/*
5561 			 * Realtime extent not lined up at the end.
5562 			 * The extent could have been split into written
5563 			 * and unwritten pieces, or we could just be
5564 			 * unmapping part of it.  But we can't really
5565 			 * get rid of part of a realtime extent.
5566 			 */
5567 			if (del.br_state == XFS_EXT_UNWRITTEN ||
5568 			    !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
5569 				/*
5570 				 * This piece is unwritten, or we're not
5571 				 * using unwritten extents.  Skip over it.
5572 				 */
5573 				ASSERT(bno >= mod);
5574 				bno -= mod > del.br_blockcount ?
5575 					del.br_blockcount : mod;
5576 				if (bno < got.br_startoff) {
5577 					if (--lastx >= 0)
5578 						xfs_bmbt_get_all(xfs_iext_get_ext(
5579 							ifp, lastx), &got);
5580 				}
5581 				continue;
5582 			}
5583 			/*
5584 			 * It's written, turn it unwritten.
5585 			 * This is better than zeroing it.
5586 			 */
5587 			ASSERT(del.br_state == XFS_EXT_NORM);
5588 			ASSERT(tp->t_blk_res > 0);
5589 			/*
5590 			 * If this spans a realtime extent boundary,
5591 			 * chop it back to the start of the one we end at.
5592 			 */
5593 			if (del.br_blockcount > mod) {
5594 				del.br_startoff += del.br_blockcount - mod;
5595 				del.br_startblock += del.br_blockcount - mod;
5596 				del.br_blockcount = mod;
5597 			}
5598 			del.br_state = XFS_EXT_UNWRITTEN;
5599 			error = xfs_bmap_add_extent_unwritten_real(tp, ip,
5600 					&lastx, &cur, &del, firstblock, dfops,
5601 					&logflags);
5602 			if (error)
5603 				goto error0;
5604 			goto nodelete;
5605 		}
5606 		if (isrt && (mod = do_mod(del.br_startblock, mp->m_sb.sb_rextsize))) {
5607 			/*
5608 			 * Realtime extent is lined up at the end but not
5609 			 * at the front.  We'll get rid of full extents if
5610 			 * we can.
5611 			 */
5612 			mod = mp->m_sb.sb_rextsize - mod;
5613 			if (del.br_blockcount > mod) {
5614 				del.br_blockcount -= mod;
5615 				del.br_startoff += mod;
5616 				del.br_startblock += mod;
5617 			} else if ((del.br_startoff == start &&
5618 				    (del.br_state == XFS_EXT_UNWRITTEN ||
5619 				     tp->t_blk_res == 0)) ||
5620 				   !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
5621 				/*
5622 				 * Can't make it unwritten.  There isn't
5623 				 * a full extent here so just skip it.
5624 				 */
5625 				ASSERT(bno >= del.br_blockcount);
5626 				bno -= del.br_blockcount;
5627 				if (got.br_startoff > bno) {
5628 					if (--lastx >= 0) {
5629 						ep = xfs_iext_get_ext(ifp,
5630 								      lastx);
5631 						xfs_bmbt_get_all(ep, &got);
5632 					}
5633 				}
5634 				continue;
5635 			} else if (del.br_state == XFS_EXT_UNWRITTEN) {
5636 				/*
5637 				 * This one is already unwritten.
5638 				 * It must have a written left neighbor.
5639 				 * Unwrite the killed part of that one and
5640 				 * try again.
5641 				 */
5642 				ASSERT(lastx > 0);
5643 				xfs_bmbt_get_all(xfs_iext_get_ext(ifp,
5644 						lastx - 1), &prev);
5645 				ASSERT(prev.br_state == XFS_EXT_NORM);
5646 				ASSERT(!isnullstartblock(prev.br_startblock));
5647 				ASSERT(del.br_startblock ==
5648 				       prev.br_startblock + prev.br_blockcount);
5649 				if (prev.br_startoff < start) {
5650 					mod = start - prev.br_startoff;
5651 					prev.br_blockcount -= mod;
5652 					prev.br_startblock += mod;
5653 					prev.br_startoff = start;
5654 				}
5655 				prev.br_state = XFS_EXT_UNWRITTEN;
5656 				lastx--;
5657 				error = xfs_bmap_add_extent_unwritten_real(tp,
5658 						ip, &lastx, &cur, &prev,
5659 						firstblock, dfops, &logflags);
5660 				if (error)
5661 					goto error0;
5662 				goto nodelete;
5663 			} else {
5664 				ASSERT(del.br_state == XFS_EXT_NORM);
5665 				del.br_state = XFS_EXT_UNWRITTEN;
5666 				error = xfs_bmap_add_extent_unwritten_real(tp,
5667 						ip, &lastx, &cur, &del,
5668 						firstblock, dfops, &logflags);
5669 				if (error)
5670 					goto error0;
5671 				goto nodelete;
5672 			}
5673 		}
5674 
5675 		/*
5676 		 * If it's the case where the directory code is running
5677 		 * with no block reservation, and the deleted block is in
5678 		 * the middle of its extent, and the resulting insert
5679 		 * of an extent would cause transformation to btree format,
5680 		 * then reject it.  The calling code will then swap
5681 		 * blocks around instead.
5682 		 * We have to do this now, rather than waiting for the
5683 		 * conversion to btree format, since the transaction
5684 		 * will be dirty.
5685 		 */
5686 		if (!wasdel && tp->t_blk_res == 0 &&
5687 		    XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
5688 		    XFS_IFORK_NEXTENTS(ip, whichfork) >= /* Note the >= */
5689 			XFS_IFORK_MAXEXT(ip, whichfork) &&
5690 		    del.br_startoff > got.br_startoff &&
5691 		    del.br_startoff + del.br_blockcount <
5692 		    got.br_startoff + got.br_blockcount) {
5693 			error = -ENOSPC;
5694 			goto error0;
5695 		}
5696 
5697 		/*
5698 		 * Unreserve quota and update realtime free space, if
5699 		 * appropriate. If delayed allocation, update the inode delalloc
5700 		 * counter now and wait to update the sb counters as
5701 		 * xfs_bmap_del_extent() might need to borrow some blocks.
5702 		 */
5703 		if (wasdel) {
5704 			ASSERT(startblockval(del.br_startblock) > 0);
5705 			if (isrt) {
5706 				xfs_filblks_t rtexts;
5707 
5708 				rtexts = XFS_FSB_TO_B(mp, del.br_blockcount);
5709 				do_div(rtexts, mp->m_sb.sb_rextsize);
5710 				xfs_mod_frextents(mp, (int64_t)rtexts);
5711 				(void)xfs_trans_reserve_quota_nblks(NULL,
5712 					ip, -((long)del.br_blockcount), 0,
5713 					XFS_QMOPT_RES_RTBLKS);
5714 			} else {
5715 				(void)xfs_trans_reserve_quota_nblks(NULL,
5716 					ip, -((long)del.br_blockcount), 0,
5717 					XFS_QMOPT_RES_REGBLKS);
5718 			}
5719 			ip->i_delayed_blks -= del.br_blockcount;
5720 			if (cur)
5721 				cur->bc_private.b.flags |=
5722 					XFS_BTCUR_BPRV_WASDEL;
5723 		} else if (cur)
5724 			cur->bc_private.b.flags &= ~XFS_BTCUR_BPRV_WASDEL;
5725 
5726 		error = xfs_bmap_del_extent(ip, tp, &lastx, dfops, cur, &del,
5727 				&tmp_logflags, whichfork, flags);
5728 		logflags |= tmp_logflags;
5729 		if (error)
5730 			goto error0;
5731 
5732 		if (!isrt && wasdel)
5733 			xfs_mod_fdblocks(mp, (int64_t)del.br_blockcount, false);
5734 
5735 		bno = del.br_startoff - 1;
5736 nodelete:
5737 		/*
5738 		 * If not done go on to the next (previous) record.
5739 		 */
5740 		if (bno != (xfs_fileoff_t)-1 && bno >= start) {
5741 			if (lastx >= 0) {
5742 				ep = xfs_iext_get_ext(ifp, lastx);
5743 				if (xfs_bmbt_get_startoff(ep) > bno) {
5744 					if (--lastx >= 0)
5745 						ep = xfs_iext_get_ext(ifp,
5746 								      lastx);
5747 				}
5748 				xfs_bmbt_get_all(ep, &got);
5749 			}
5750 			extno++;
5751 		}
5752 	}
5753 	if (bno == (xfs_fileoff_t)-1 || bno < start || lastx < 0)
5754 		*rlen = 0;
5755 	else
5756 		*rlen = bno - start + 1;
5757 
5758 	/*
5759 	 * Convert to a btree if necessary.
5760 	 */
5761 	if (xfs_bmap_needs_btree(ip, whichfork)) {
5762 		ASSERT(cur == NULL);
5763 		error = xfs_bmap_extents_to_btree(tp, ip, firstblock, dfops,
5764 			&cur, 0, &tmp_logflags, whichfork);
5765 		logflags |= tmp_logflags;
5766 		if (error)
5767 			goto error0;
5768 	}
5769 	/*
5770 	 * transform from btree to extents, give it cur
5771 	 */
5772 	else if (xfs_bmap_wants_extents(ip, whichfork)) {
5773 		ASSERT(cur != NULL);
5774 		error = xfs_bmap_btree_to_extents(tp, ip, cur, &tmp_logflags,
5775 			whichfork);
5776 		logflags |= tmp_logflags;
5777 		if (error)
5778 			goto error0;
5779 	}
5780 	/*
5781 	 * transform from extents to local?
5782 	 */
5783 	error = 0;
5784 error0:
5785 	/*
5786 	 * Log everything.  Do this after conversion, there's no point in
5787 	 * logging the extent records if we've converted to btree format.
5788 	 */
5789 	if ((logflags & xfs_ilog_fext(whichfork)) &&
5790 	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
5791 		logflags &= ~xfs_ilog_fext(whichfork);
5792 	else if ((logflags & xfs_ilog_fbroot(whichfork)) &&
5793 		 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
5794 		logflags &= ~xfs_ilog_fbroot(whichfork);
5795 	/*
5796 	 * Log inode even in the error case, if the transaction
5797 	 * is dirty we'll need to shut down the filesystem.
5798 	 */
5799 	if (logflags)
5800 		xfs_trans_log_inode(tp, ip, logflags);
5801 	if (cur) {
5802 		if (!error) {
5803 			*firstblock = cur->bc_private.b.firstblock;
5804 			cur->bc_private.b.allocated = 0;
5805 		}
5806 		xfs_btree_del_cursor(cur,
5807 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
5808 	}
5809 	return error;
5810 }
5811 
5812 /* Unmap a range of a file. */
5813 int
5814 xfs_bunmapi(
5815 	xfs_trans_t		*tp,
5816 	struct xfs_inode	*ip,
5817 	xfs_fileoff_t		bno,
5818 	xfs_filblks_t		len,
5819 	int			flags,
5820 	xfs_extnum_t		nexts,
5821 	xfs_fsblock_t		*firstblock,
5822 	struct xfs_defer_ops	*dfops,
5823 	int			*done)
5824 {
5825 	int			error;
5826 
5827 	error = __xfs_bunmapi(tp, ip, bno, &len, flags, nexts, firstblock,
5828 			dfops);
5829 	*done = (len == 0);
5830 	return error;
5831 }
5832 
5833 /*
5834  * Determine whether an extent shift can be accomplished by a merge with the
5835  * extent that precedes the target hole of the shift.
5836  */
5837 STATIC bool
5838 xfs_bmse_can_merge(
5839 	struct xfs_bmbt_irec	*left,	/* preceding extent */
5840 	struct xfs_bmbt_irec	*got,	/* current extent to shift */
5841 	xfs_fileoff_t		shift)	/* shift fsb */
5842 {
5843 	xfs_fileoff_t		startoff;
5844 
5845 	startoff = got->br_startoff - shift;
5846 
5847 	/*
5848 	 * The extent, once shifted, must be adjacent in-file and on-disk with
5849 	 * the preceding extent.
5850 	 */
5851 	if ((left->br_startoff + left->br_blockcount != startoff) ||
5852 	    (left->br_startblock + left->br_blockcount != got->br_startblock) ||
5853 	    (left->br_state != got->br_state) ||
5854 	    (left->br_blockcount + got->br_blockcount > MAXEXTLEN))
5855 		return false;
5856 
5857 	return true;
5858 }
5859 
5860 /*
5861  * A bmap extent shift adjusts the file offset of an extent to fill a preceding
5862  * hole in the file. If an extent shift would result in the extent being fully
5863  * adjacent to the extent that currently precedes the hole, we can merge with
5864  * the preceding extent rather than do the shift.
5865  *
5866  * This function assumes the caller has verified a shift-by-merge is possible
5867  * with the provided extents via xfs_bmse_can_merge().
5868  */
5869 STATIC int
5870 xfs_bmse_merge(
5871 	struct xfs_inode		*ip,
5872 	int				whichfork,
5873 	xfs_fileoff_t			shift,		/* shift fsb */
5874 	int				current_ext,	/* idx of gotp */
5875 	struct xfs_bmbt_rec_host	*gotp,		/* extent to shift */
5876 	struct xfs_bmbt_rec_host	*leftp,		/* preceding extent */
5877 	struct xfs_btree_cur		*cur,
5878 	int				*logflags)	/* output */
5879 {
5880 	struct xfs_bmbt_irec		got;
5881 	struct xfs_bmbt_irec		left;
5882 	xfs_filblks_t			blockcount;
5883 	int				error, i;
5884 	struct xfs_mount		*mp = ip->i_mount;
5885 
5886 	xfs_bmbt_get_all(gotp, &got);
5887 	xfs_bmbt_get_all(leftp, &left);
5888 	blockcount = left.br_blockcount + got.br_blockcount;
5889 
5890 	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
5891 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5892 	ASSERT(xfs_bmse_can_merge(&left, &got, shift));
5893 
5894 	/*
5895 	 * Merge the in-core extents. Note that the host record pointers and
5896 	 * current_ext index are invalid once the extent has been removed via
5897 	 * xfs_iext_remove().
5898 	 */
5899 	xfs_bmbt_set_blockcount(leftp, blockcount);
5900 	xfs_iext_remove(ip, current_ext, 1, 0);
5901 
5902 	/*
5903 	 * Update the on-disk extent count, the btree if necessary and log the
5904 	 * inode.
5905 	 */
5906 	XFS_IFORK_NEXT_SET(ip, whichfork,
5907 			   XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
5908 	*logflags |= XFS_ILOG_CORE;
5909 	if (!cur) {
5910 		*logflags |= XFS_ILOG_DEXT;
5911 		return 0;
5912 	}
5913 
5914 	/* lookup and remove the extent to merge */
5915 	error = xfs_bmbt_lookup_eq(cur, got.br_startoff, got.br_startblock,
5916 				   got.br_blockcount, &i);
5917 	if (error)
5918 		return error;
5919 	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5920 
5921 	error = xfs_btree_delete(cur, &i);
5922 	if (error)
5923 		return error;
5924 	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5925 
5926 	/* lookup and update size of the previous extent */
5927 	error = xfs_bmbt_lookup_eq(cur, left.br_startoff, left.br_startblock,
5928 				   left.br_blockcount, &i);
5929 	if (error)
5930 		return error;
5931 	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5932 
5933 	left.br_blockcount = blockcount;
5934 
5935 	return xfs_bmbt_update(cur, left.br_startoff, left.br_startblock,
5936 			       left.br_blockcount, left.br_state);
5937 }
5938 
5939 /*
5940  * Shift a single extent.
5941  */
5942 STATIC int
5943 xfs_bmse_shift_one(
5944 	struct xfs_inode		*ip,
5945 	int				whichfork,
5946 	xfs_fileoff_t			offset_shift_fsb,
5947 	int				*current_ext,
5948 	struct xfs_bmbt_rec_host	*gotp,
5949 	struct xfs_btree_cur		*cur,
5950 	int				*logflags,
5951 	enum shift_direction		direction,
5952 	struct xfs_defer_ops		*dfops)
5953 {
5954 	struct xfs_ifork		*ifp;
5955 	struct xfs_mount		*mp;
5956 	xfs_fileoff_t			startoff;
5957 	struct xfs_bmbt_rec_host	*adj_irecp;
5958 	struct xfs_bmbt_irec		got;
5959 	struct xfs_bmbt_irec		adj_irec;
5960 	int				error;
5961 	int				i;
5962 	int				total_extents;
5963 
5964 	mp = ip->i_mount;
5965 	ifp = XFS_IFORK_PTR(ip, whichfork);
5966 	total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
5967 
5968 	xfs_bmbt_get_all(gotp, &got);
5969 
5970 	/* delalloc extents should be prevented by caller */
5971 	XFS_WANT_CORRUPTED_RETURN(mp, !isnullstartblock(got.br_startblock));
5972 
5973 	if (direction == SHIFT_LEFT) {
5974 		startoff = got.br_startoff - offset_shift_fsb;
5975 
5976 		/*
5977 		 * Check for merge if we've got an extent to the left,
5978 		 * otherwise make sure there's enough room at the start
5979 		 * of the file for the shift.
5980 		 */
5981 		if (!*current_ext) {
5982 			if (got.br_startoff < offset_shift_fsb)
5983 				return -EINVAL;
5984 			goto update_current_ext;
5985 		}
5986 		/*
5987 		 * grab the left extent and check for a large
5988 		 * enough hole.
5989 		 */
5990 		adj_irecp = xfs_iext_get_ext(ifp, *current_ext - 1);
5991 		xfs_bmbt_get_all(adj_irecp, &adj_irec);
5992 
5993 		if (startoff <
5994 		    adj_irec.br_startoff + adj_irec.br_blockcount)
5995 			return -EINVAL;
5996 
5997 		/* check whether to merge the extent or shift it down */
5998 		if (xfs_bmse_can_merge(&adj_irec, &got,
5999 				       offset_shift_fsb)) {
6000 			error = xfs_bmse_merge(ip, whichfork, offset_shift_fsb,
6001 					       *current_ext, gotp, adj_irecp,
6002 					       cur, logflags);
6003 			if (error)
6004 				return error;
6005 			adj_irec = got;
6006 			goto update_rmap;
6007 		}
6008 	} else {
6009 		startoff = got.br_startoff + offset_shift_fsb;
6010 		/* nothing to move if this is the last extent */
6011 		if (*current_ext >= (total_extents - 1))
6012 			goto update_current_ext;
6013 		/*
6014 		 * If this is not the last extent in the file, make sure there
6015 		 * is enough room between current extent and next extent for
6016 		 * accommodating the shift.
6017 		 */
6018 		adj_irecp = xfs_iext_get_ext(ifp, *current_ext + 1);
6019 		xfs_bmbt_get_all(adj_irecp, &adj_irec);
6020 		if (startoff + got.br_blockcount > adj_irec.br_startoff)
6021 			return -EINVAL;
6022 		/*
6023 		 * Unlike a left shift (which involves a hole punch),
6024 		 * a right shift does not modify extent neighbors
6025 		 * in any way. We should never find mergeable extents
6026 		 * in this scenario. Check anyways and warn if we
6027 		 * encounter two extents that could be one.
6028 		 */
6029 		if (xfs_bmse_can_merge(&got, &adj_irec, offset_shift_fsb))
6030 			WARN_ON_ONCE(1);
6031 	}
6032 	/*
6033 	 * Increment the extent index for the next iteration, update the start
6034 	 * offset of the in-core extent and update the btree if applicable.
6035 	 */
6036 update_current_ext:
6037 	if (direction == SHIFT_LEFT)
6038 		(*current_ext)++;
6039 	else
6040 		(*current_ext)--;
6041 	xfs_bmbt_set_startoff(gotp, startoff);
6042 	*logflags |= XFS_ILOG_CORE;
6043 	adj_irec = got;
6044 	if (!cur) {
6045 		*logflags |= XFS_ILOG_DEXT;
6046 		goto update_rmap;
6047 	}
6048 
6049 	error = xfs_bmbt_lookup_eq(cur, got.br_startoff, got.br_startblock,
6050 				   got.br_blockcount, &i);
6051 	if (error)
6052 		return error;
6053 	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
6054 
6055 	got.br_startoff = startoff;
6056 	error = xfs_bmbt_update(cur, got.br_startoff, got.br_startblock,
6057 			got.br_blockcount, got.br_state);
6058 	if (error)
6059 		return error;
6060 
6061 update_rmap:
6062 	/* update reverse mapping */
6063 	error = xfs_rmap_unmap_extent(mp, dfops, ip, whichfork, &adj_irec);
6064 	if (error)
6065 		return error;
6066 	adj_irec.br_startoff = startoff;
6067 	return xfs_rmap_map_extent(mp, dfops, ip, whichfork, &adj_irec);
6068 }
6069 
6070 /*
6071  * Shift extent records to the left/right to cover/create a hole.
6072  *
6073  * The maximum number of extents to be shifted in a single operation is
6074  * @num_exts. @stop_fsb specifies the file offset at which to stop shift and the
6075  * file offset where we've left off is returned in @next_fsb. @offset_shift_fsb
6076  * is the length by which each extent is shifted. If there is no hole to shift
6077  * the extents into, this will be considered invalid operation and we abort
6078  * immediately.
6079  */
6080 int
6081 xfs_bmap_shift_extents(
6082 	struct xfs_trans	*tp,
6083 	struct xfs_inode	*ip,
6084 	xfs_fileoff_t		*next_fsb,
6085 	xfs_fileoff_t		offset_shift_fsb,
6086 	int			*done,
6087 	xfs_fileoff_t		stop_fsb,
6088 	xfs_fsblock_t		*firstblock,
6089 	struct xfs_defer_ops	*dfops,
6090 	enum shift_direction	direction,
6091 	int			num_exts)
6092 {
6093 	struct xfs_btree_cur		*cur = NULL;
6094 	struct xfs_bmbt_rec_host	*gotp;
6095 	struct xfs_bmbt_irec            got;
6096 	struct xfs_mount		*mp = ip->i_mount;
6097 	struct xfs_ifork		*ifp;
6098 	xfs_extnum_t			nexts = 0;
6099 	xfs_extnum_t			current_ext;
6100 	xfs_extnum_t			total_extents;
6101 	xfs_extnum_t			stop_extent;
6102 	int				error = 0;
6103 	int				whichfork = XFS_DATA_FORK;
6104 	int				logflags = 0;
6105 
6106 	if (unlikely(XFS_TEST_ERROR(
6107 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
6108 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
6109 	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
6110 		XFS_ERROR_REPORT("xfs_bmap_shift_extents",
6111 				 XFS_ERRLEVEL_LOW, mp);
6112 		return -EFSCORRUPTED;
6113 	}
6114 
6115 	if (XFS_FORCED_SHUTDOWN(mp))
6116 		return -EIO;
6117 
6118 	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
6119 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
6120 	ASSERT(direction == SHIFT_LEFT || direction == SHIFT_RIGHT);
6121 	ASSERT(*next_fsb != NULLFSBLOCK || direction == SHIFT_RIGHT);
6122 
6123 	ifp = XFS_IFORK_PTR(ip, whichfork);
6124 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
6125 		/* Read in all the extents */
6126 		error = xfs_iread_extents(tp, ip, whichfork);
6127 		if (error)
6128 			return error;
6129 	}
6130 
6131 	if (ifp->if_flags & XFS_IFBROOT) {
6132 		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
6133 		cur->bc_private.b.firstblock = *firstblock;
6134 		cur->bc_private.b.dfops = dfops;
6135 		cur->bc_private.b.flags = 0;
6136 	}
6137 
6138 	/*
6139 	 * There may be delalloc extents in the data fork before the range we
6140 	 * are collapsing out, so we cannot use the count of real extents here.
6141 	 * Instead we have to calculate it from the incore fork.
6142 	 */
6143 	total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
6144 	if (total_extents == 0) {
6145 		*done = 1;
6146 		goto del_cursor;
6147 	}
6148 
6149 	/*
6150 	 * In case of first right shift, we need to initialize next_fsb
6151 	 */
6152 	if (*next_fsb == NULLFSBLOCK) {
6153 		gotp = xfs_iext_get_ext(ifp, total_extents - 1);
6154 		xfs_bmbt_get_all(gotp, &got);
6155 		*next_fsb = got.br_startoff;
6156 		if (stop_fsb > *next_fsb) {
6157 			*done = 1;
6158 			goto del_cursor;
6159 		}
6160 	}
6161 
6162 	/* Lookup the extent index at which we have to stop */
6163 	if (direction == SHIFT_RIGHT) {
6164 		gotp = xfs_iext_bno_to_ext(ifp, stop_fsb, &stop_extent);
6165 		/* Make stop_extent exclusive of shift range */
6166 		stop_extent--;
6167 	} else
6168 		stop_extent = total_extents;
6169 
6170 	/*
6171 	 * Look up the extent index for the fsb where we start shifting. We can
6172 	 * henceforth iterate with current_ext as extent list changes are locked
6173 	 * out via ilock.
6174 	 *
6175 	 * gotp can be null in 2 cases: 1) if there are no extents or 2)
6176 	 * *next_fsb lies in a hole beyond which there are no extents. Either
6177 	 * way, we are done.
6178 	 */
6179 	gotp = xfs_iext_bno_to_ext(ifp, *next_fsb, &current_ext);
6180 	if (!gotp) {
6181 		*done = 1;
6182 		goto del_cursor;
6183 	}
6184 
6185 	/* some sanity checking before we finally start shifting extents */
6186 	if ((direction == SHIFT_LEFT && current_ext >= stop_extent) ||
6187 	     (direction == SHIFT_RIGHT && current_ext <= stop_extent)) {
6188 		error = -EIO;
6189 		goto del_cursor;
6190 	}
6191 
6192 	while (nexts++ < num_exts) {
6193 		error = xfs_bmse_shift_one(ip, whichfork, offset_shift_fsb,
6194 					   &current_ext, gotp, cur, &logflags,
6195 					   direction, dfops);
6196 		if (error)
6197 			goto del_cursor;
6198 		/*
6199 		 * If there was an extent merge during the shift, the extent
6200 		 * count can change. Update the total and grade the next record.
6201 		 */
6202 		if (direction == SHIFT_LEFT) {
6203 			total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
6204 			stop_extent = total_extents;
6205 		}
6206 
6207 		if (current_ext == stop_extent) {
6208 			*done = 1;
6209 			*next_fsb = NULLFSBLOCK;
6210 			break;
6211 		}
6212 		gotp = xfs_iext_get_ext(ifp, current_ext);
6213 	}
6214 
6215 	if (!*done) {
6216 		xfs_bmbt_get_all(gotp, &got);
6217 		*next_fsb = got.br_startoff;
6218 	}
6219 
6220 del_cursor:
6221 	if (cur)
6222 		xfs_btree_del_cursor(cur,
6223 			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
6224 
6225 	if (logflags)
6226 		xfs_trans_log_inode(tp, ip, logflags);
6227 
6228 	return error;
6229 }
6230 
6231 /*
6232  * Splits an extent into two extents at split_fsb block such that it is
6233  * the first block of the current_ext. @current_ext is a target extent
6234  * to be split. @split_fsb is a block where the extents is split.
6235  * If split_fsb lies in a hole or the first block of extents, just return 0.
6236  */
6237 STATIC int
6238 xfs_bmap_split_extent_at(
6239 	struct xfs_trans	*tp,
6240 	struct xfs_inode	*ip,
6241 	xfs_fileoff_t		split_fsb,
6242 	xfs_fsblock_t		*firstfsb,
6243 	struct xfs_defer_ops	*dfops)
6244 {
6245 	int				whichfork = XFS_DATA_FORK;
6246 	struct xfs_btree_cur		*cur = NULL;
6247 	struct xfs_bmbt_rec_host	*gotp;
6248 	struct xfs_bmbt_irec		got;
6249 	struct xfs_bmbt_irec		new; /* split extent */
6250 	struct xfs_mount		*mp = ip->i_mount;
6251 	struct xfs_ifork		*ifp;
6252 	xfs_fsblock_t			gotblkcnt; /* new block count for got */
6253 	xfs_extnum_t			current_ext;
6254 	int				error = 0;
6255 	int				logflags = 0;
6256 	int				i = 0;
6257 
6258 	if (unlikely(XFS_TEST_ERROR(
6259 	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
6260 	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
6261 	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
6262 		XFS_ERROR_REPORT("xfs_bmap_split_extent_at",
6263 				 XFS_ERRLEVEL_LOW, mp);
6264 		return -EFSCORRUPTED;
6265 	}
6266 
6267 	if (XFS_FORCED_SHUTDOWN(mp))
6268 		return -EIO;
6269 
6270 	ifp = XFS_IFORK_PTR(ip, whichfork);
6271 	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
6272 		/* Read in all the extents */
6273 		error = xfs_iread_extents(tp, ip, whichfork);
6274 		if (error)
6275 			return error;
6276 	}
6277 
6278 	/*
6279 	 * gotp can be null in 2 cases: 1) if there are no extents
6280 	 * or 2) split_fsb lies in a hole beyond which there are
6281 	 * no extents. Either way, we are done.
6282 	 */
6283 	gotp = xfs_iext_bno_to_ext(ifp, split_fsb, &current_ext);
6284 	if (!gotp)
6285 		return 0;
6286 
6287 	xfs_bmbt_get_all(gotp, &got);
6288 
6289 	/*
6290 	 * Check split_fsb lies in a hole or the start boundary offset
6291 	 * of the extent.
6292 	 */
6293 	if (got.br_startoff >= split_fsb)
6294 		return 0;
6295 
6296 	gotblkcnt = split_fsb - got.br_startoff;
6297 	new.br_startoff = split_fsb;
6298 	new.br_startblock = got.br_startblock + gotblkcnt;
6299 	new.br_blockcount = got.br_blockcount - gotblkcnt;
6300 	new.br_state = got.br_state;
6301 
6302 	if (ifp->if_flags & XFS_IFBROOT) {
6303 		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
6304 		cur->bc_private.b.firstblock = *firstfsb;
6305 		cur->bc_private.b.dfops = dfops;
6306 		cur->bc_private.b.flags = 0;
6307 		error = xfs_bmbt_lookup_eq(cur, got.br_startoff,
6308 				got.br_startblock,
6309 				got.br_blockcount,
6310 				&i);
6311 		if (error)
6312 			goto del_cursor;
6313 		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
6314 	}
6315 
6316 	xfs_bmbt_set_blockcount(gotp, gotblkcnt);
6317 	got.br_blockcount = gotblkcnt;
6318 
6319 	logflags = XFS_ILOG_CORE;
6320 	if (cur) {
6321 		error = xfs_bmbt_update(cur, got.br_startoff,
6322 				got.br_startblock,
6323 				got.br_blockcount,
6324 				got.br_state);
6325 		if (error)
6326 			goto del_cursor;
6327 	} else
6328 		logflags |= XFS_ILOG_DEXT;
6329 
6330 	/* Add new extent */
6331 	current_ext++;
6332 	xfs_iext_insert(ip, current_ext, 1, &new, 0);
6333 	XFS_IFORK_NEXT_SET(ip, whichfork,
6334 			   XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
6335 
6336 	if (cur) {
6337 		error = xfs_bmbt_lookup_eq(cur, new.br_startoff,
6338 				new.br_startblock, new.br_blockcount,
6339 				&i);
6340 		if (error)
6341 			goto del_cursor;
6342 		XFS_WANT_CORRUPTED_GOTO(mp, i == 0, del_cursor);
6343 		cur->bc_rec.b.br_state = new.br_state;
6344 
6345 		error = xfs_btree_insert(cur, &i);
6346 		if (error)
6347 			goto del_cursor;
6348 		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
6349 	}
6350 
6351 	/*
6352 	 * Convert to a btree if necessary.
6353 	 */
6354 	if (xfs_bmap_needs_btree(ip, whichfork)) {
6355 		int tmp_logflags; /* partial log flag return val */
6356 
6357 		ASSERT(cur == NULL);
6358 		error = xfs_bmap_extents_to_btree(tp, ip, firstfsb, dfops,
6359 				&cur, 0, &tmp_logflags, whichfork);
6360 		logflags |= tmp_logflags;
6361 	}
6362 
6363 del_cursor:
6364 	if (cur) {
6365 		cur->bc_private.b.allocated = 0;
6366 		xfs_btree_del_cursor(cur,
6367 				error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
6368 	}
6369 
6370 	if (logflags)
6371 		xfs_trans_log_inode(tp, ip, logflags);
6372 	return error;
6373 }
6374 
6375 int
6376 xfs_bmap_split_extent(
6377 	struct xfs_inode        *ip,
6378 	xfs_fileoff_t           split_fsb)
6379 {
6380 	struct xfs_mount        *mp = ip->i_mount;
6381 	struct xfs_trans        *tp;
6382 	struct xfs_defer_ops    dfops;
6383 	xfs_fsblock_t           firstfsb;
6384 	int                     error;
6385 
6386 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write,
6387 			XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp);
6388 	if (error)
6389 		return error;
6390 
6391 	xfs_ilock(ip, XFS_ILOCK_EXCL);
6392 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
6393 
6394 	xfs_defer_init(&dfops, &firstfsb);
6395 
6396 	error = xfs_bmap_split_extent_at(tp, ip, split_fsb,
6397 			&firstfsb, &dfops);
6398 	if (error)
6399 		goto out;
6400 
6401 	error = xfs_defer_finish(&tp, &dfops, NULL);
6402 	if (error)
6403 		goto out;
6404 
6405 	return xfs_trans_commit(tp);
6406 
6407 out:
6408 	xfs_defer_cancel(&dfops);
6409 	xfs_trans_cancel(tp);
6410 	return error;
6411 }
6412 
6413 /* Deferred mapping is only for real extents in the data fork. */
6414 static bool
6415 xfs_bmap_is_update_needed(
6416 	struct xfs_bmbt_irec	*bmap)
6417 {
6418 	return  bmap->br_startblock != HOLESTARTBLOCK &&
6419 		bmap->br_startblock != DELAYSTARTBLOCK;
6420 }
6421 
6422 /* Record a bmap intent. */
6423 static int
6424 __xfs_bmap_add(
6425 	struct xfs_mount		*mp,
6426 	struct xfs_defer_ops		*dfops,
6427 	enum xfs_bmap_intent_type	type,
6428 	struct xfs_inode		*ip,
6429 	int				whichfork,
6430 	struct xfs_bmbt_irec		*bmap)
6431 {
6432 	int				error;
6433 	struct xfs_bmap_intent		*bi;
6434 
6435 	trace_xfs_bmap_defer(mp,
6436 			XFS_FSB_TO_AGNO(mp, bmap->br_startblock),
6437 			type,
6438 			XFS_FSB_TO_AGBNO(mp, bmap->br_startblock),
6439 			ip->i_ino, whichfork,
6440 			bmap->br_startoff,
6441 			bmap->br_blockcount,
6442 			bmap->br_state);
6443 
6444 	bi = kmem_alloc(sizeof(struct xfs_bmap_intent), KM_SLEEP | KM_NOFS);
6445 	INIT_LIST_HEAD(&bi->bi_list);
6446 	bi->bi_type = type;
6447 	bi->bi_owner = ip;
6448 	bi->bi_whichfork = whichfork;
6449 	bi->bi_bmap = *bmap;
6450 
6451 	error = xfs_defer_join(dfops, bi->bi_owner);
6452 	if (error) {
6453 		kmem_free(bi);
6454 		return error;
6455 	}
6456 
6457 	xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list);
6458 	return 0;
6459 }
6460 
6461 /* Map an extent into a file. */
6462 int
6463 xfs_bmap_map_extent(
6464 	struct xfs_mount	*mp,
6465 	struct xfs_defer_ops	*dfops,
6466 	struct xfs_inode	*ip,
6467 	struct xfs_bmbt_irec	*PREV)
6468 {
6469 	if (!xfs_bmap_is_update_needed(PREV))
6470 		return 0;
6471 
6472 	return __xfs_bmap_add(mp, dfops, XFS_BMAP_MAP, ip,
6473 			XFS_DATA_FORK, PREV);
6474 }
6475 
6476 /* Unmap an extent out of a file. */
6477 int
6478 xfs_bmap_unmap_extent(
6479 	struct xfs_mount	*mp,
6480 	struct xfs_defer_ops	*dfops,
6481 	struct xfs_inode	*ip,
6482 	struct xfs_bmbt_irec	*PREV)
6483 {
6484 	if (!xfs_bmap_is_update_needed(PREV))
6485 		return 0;
6486 
6487 	return __xfs_bmap_add(mp, dfops, XFS_BMAP_UNMAP, ip,
6488 			XFS_DATA_FORK, PREV);
6489 }
6490 
6491 /*
6492  * Process one of the deferred bmap operations.  We pass back the
6493  * btree cursor to maintain our lock on the bmapbt between calls.
6494  */
6495 int
6496 xfs_bmap_finish_one(
6497 	struct xfs_trans		*tp,
6498 	struct xfs_defer_ops		*dfops,
6499 	struct xfs_inode		*ip,
6500 	enum xfs_bmap_intent_type	type,
6501 	int				whichfork,
6502 	xfs_fileoff_t			startoff,
6503 	xfs_fsblock_t			startblock,
6504 	xfs_filblks_t			blockcount,
6505 	xfs_exntst_t			state)
6506 {
6507 	struct xfs_bmbt_irec		bmap;
6508 	int				nimaps = 1;
6509 	xfs_fsblock_t			firstfsb;
6510 	int				flags = XFS_BMAPI_REMAP;
6511 	int				done;
6512 	int				error = 0;
6513 
6514 	bmap.br_startblock = startblock;
6515 	bmap.br_startoff = startoff;
6516 	bmap.br_blockcount = blockcount;
6517 	bmap.br_state = state;
6518 
6519 	trace_xfs_bmap_deferred(tp->t_mountp,
6520 			XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
6521 			XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
6522 			ip->i_ino, whichfork, startoff, blockcount, state);
6523 
6524 	if (whichfork != XFS_DATA_FORK && whichfork != XFS_ATTR_FORK)
6525 		return -EFSCORRUPTED;
6526 	if (whichfork == XFS_ATTR_FORK)
6527 		flags |= XFS_BMAPI_ATTRFORK;
6528 
6529 	if (XFS_TEST_ERROR(false, tp->t_mountp,
6530 			XFS_ERRTAG_BMAP_FINISH_ONE,
6531 			XFS_RANDOM_BMAP_FINISH_ONE))
6532 		return -EIO;
6533 
6534 	switch (type) {
6535 	case XFS_BMAP_MAP:
6536 		firstfsb = bmap.br_startblock;
6537 		error = xfs_bmapi_write(tp, ip, bmap.br_startoff,
6538 					bmap.br_blockcount, flags, &firstfsb,
6539 					bmap.br_blockcount, &bmap, &nimaps,
6540 					dfops);
6541 		break;
6542 	case XFS_BMAP_UNMAP:
6543 		error = xfs_bunmapi(tp, ip, bmap.br_startoff,
6544 				bmap.br_blockcount, flags, 1, &firstfsb,
6545 				dfops, &done);
6546 		ASSERT(done);
6547 		break;
6548 	default:
6549 		ASSERT(0);
6550 		error = -EFSCORRUPTED;
6551 	}
6552 
6553 	return error;
6554 }
6555