xfs_bmap.c 185.3 KB
Newer Older
L
Linus Torvalds 已提交
1
/*
2
 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3
 * All Rights Reserved.
L
Linus Torvalds 已提交
4
 *
5 6
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
L
Linus Torvalds 已提交
7 8
 * published by the Free Software Foundation.
 *
9 10 11 12
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
L
Linus Torvalds 已提交
13
 *
14 15 16
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
L
Linus Torvalds 已提交
17 18
 */
#include "xfs.h"
19
#include "xfs_fs.h"
20
#include "xfs_shared.h"
21 22 23
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
24
#include "xfs_bit.h"
L
Linus Torvalds 已提交
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"
L
Linus Torvalds 已提交
31
#include "xfs_inode.h"
32
#include "xfs_btree.h"
33
#include "xfs_trans.h"
34
#include "xfs_inode_item.h"
L
Linus Torvalds 已提交
35 36 37
#include "xfs_extfree_item.h"
#include "xfs_alloc.h"
#include "xfs_bmap.h"
D
Dave Chinner 已提交
38
#include "xfs_bmap_util.h"
39
#include "xfs_bmap_btree.h"
L
Linus Torvalds 已提交
40 41 42 43 44
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_quota.h"
#include "xfs_trans_space.h"
#include "xfs_buf_item.h"
C
Christoph Hellwig 已提交
45
#include "xfs_trace.h"
46
#include "xfs_symlink.h"
47 48
#include "xfs_attr_leaf.h"
#include "xfs_filestream.h"
49
#include "xfs_rmap.h"
50
#include "xfs_ag_resv.h"
51
#include "xfs_refcount.h"
L
Linus Torvalds 已提交
52 53 54 55 56


kmem_zone_t		*xfs_bmap_free_item_zone;

/*
57
 * Miscellaneous helper functions
L
Linus Torvalds 已提交
58 59 60
 */

/*
61 62
 * Compute and fill in the value of the maximum depth of a bmap btree
 * in this filesystem.  Done once, during mount.
L
Linus Torvalds 已提交
63
 */
64 65 66 67 68 69 70 71 72 73 74 75
void
xfs_bmap_compute_maxlevels(
	xfs_mount_t	*mp,		/* file system mount structure */
	int		whichfork)	/* data or attr fork */
{
	int		level;		/* btree level */
	uint		maxblocks;	/* max blocks at this level */
	uint		maxleafents;	/* max leaf entries possible */
	int		maxrootrecs;	/* max records in root block */
	int		minleafrecs;	/* min records in leaf block */
	int		minnoderecs;	/* min records in node block */
	int		sz;		/* root block size */
L
Linus Torvalds 已提交
76

77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
	/*
	 * The maximum number of extents in a file, hence the maximum
	 * number of leaf entries, is controlled by the type of di_nextents
	 * (a signed 32-bit number, xfs_extnum_t), or by di_anextents
	 * (a signed 16-bit number, xfs_aextnum_t).
	 *
	 * Note that we can no longer assume that if we are in ATTR1 that
	 * the fork offset of all the inodes will be
	 * (xfs_default_attroffset(ip) >> 3) because we could have mounted
	 * with ATTR2 and then mounted back with ATTR1, keeping the
	 * di_forkoff's fixed but probably at various positions. Therefore,
	 * for both ATTR1 and ATTR2 we have to assume the worst case scenario
	 * of a minimum size available.
	 */
	if (whichfork == XFS_DATA_FORK) {
		maxleafents = MAXEXTNUM;
		sz = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
	} else {
		maxleafents = MAXAEXTNUM;
		sz = XFS_BMDR_SPACE_CALC(MINABTPTRS);
	}
98
	maxrootrecs = xfs_bmdr_maxrecs(sz, 0);
99 100 101 102 103 104 105 106 107 108 109
	minleafrecs = mp->m_bmap_dmnr[0];
	minnoderecs = mp->m_bmap_dmnr[1];
	maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
	for (level = 1; maxblocks > 1; level++) {
		if (maxblocks <= maxrootrecs)
			maxblocks = 1;
		else
			maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
	}
	mp->m_bm_maxlevels[whichfork] = level;
}
110

111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138
STATIC int				/* error */
xfs_bmbt_lookup_eq(
	struct xfs_btree_cur	*cur,
	xfs_fileoff_t		off,
	xfs_fsblock_t		bno,
	xfs_filblks_t		len,
	int			*stat)	/* success/failure */
{
	cur->bc_rec.b.br_startoff = off;
	cur->bc_rec.b.br_startblock = bno;
	cur->bc_rec.b.br_blockcount = len;
	return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
}

STATIC int				/* error */
xfs_bmbt_lookup_ge(
	struct xfs_btree_cur	*cur,
	xfs_fileoff_t		off,
	xfs_fsblock_t		bno,
	xfs_filblks_t		len,
	int			*stat)	/* success/failure */
{
	cur->bc_rec.b.br_startoff = off;
	cur->bc_rec.b.br_startblock = bno;
	cur->bc_rec.b.br_blockcount = len;
	return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
}

139
/*
140 141 142 143
 * Check if the inode needs to be converted to btree format.
 */
static inline bool xfs_bmap_needs_btree(struct xfs_inode *ip, int whichfork)
{
144 145
	return whichfork != XFS_COW_FORK &&
		XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
146 147 148 149 150 151 152 153 154
		XFS_IFORK_NEXTENTS(ip, whichfork) >
			XFS_IFORK_MAXEXT(ip, whichfork);
}

/*
 * Check if the inode should be converted to extent format.
 */
static inline bool xfs_bmap_wants_extents(struct xfs_inode *ip, int whichfork)
{
155 156
	return whichfork != XFS_COW_FORK &&
		XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE &&
157 158 159 160 161 162
		XFS_IFORK_NEXTENTS(ip, whichfork) <=
			XFS_IFORK_MAXEXT(ip, whichfork);
}

/*
 * Update the record referred to by cur to the value given
163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178
 * by [off, bno, len, state].
 * This either works (return 0) or gets an EFSCORRUPTED error.
 */
STATIC int
xfs_bmbt_update(
	struct xfs_btree_cur	*cur,
	xfs_fileoff_t		off,
	xfs_fsblock_t		bno,
	xfs_filblks_t		len,
	xfs_exntst_t		state)
{
	union xfs_btree_rec	rec;

	xfs_bmbt_disk_set_allf(&rec.bmbt, off, bno, len, state);
	return xfs_btree_update(cur, &rec);
}
179

L
Linus Torvalds 已提交
180
/*
181 182
 * Compute the worst-case number of indirect blocks that will be used
 * for ip's delayed extent of length "len".
L
Linus Torvalds 已提交
183
 */
184 185 186 187
STATIC xfs_filblks_t
xfs_bmap_worst_indlen(
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_filblks_t	len)		/* delayed extent length */
L
Linus Torvalds 已提交
188
{
189 190 191 192
	int		level;		/* btree level number */
	int		maxrecs;	/* maximum record count at this level */
	xfs_mount_t	*mp;		/* mount structure */
	xfs_filblks_t	rval;		/* return value */
L
Linus Torvalds 已提交
193 194

	mp = ip->i_mount;
195 196 197 198 199 200 201 202 203 204 205 206
	maxrecs = mp->m_bmap_dmxr[0];
	for (level = 0, rval = 0;
	     level < XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK);
	     level++) {
		len += maxrecs - 1;
		do_div(len, maxrecs);
		rval += len;
		if (len == 1)
			return rval + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) -
				level - 1;
		if (level == 0)
			maxrecs = mp->m_bmap_dmxr[1];
L
Linus Torvalds 已提交
207
	}
208
	return rval;
L
Linus Torvalds 已提交
209 210 211
}

/*
212
 * Calculate the default attribute fork offset for newly created inodes.
L
Linus Torvalds 已提交
213
 */
214 215 216
uint
xfs_default_attroffset(
	struct xfs_inode	*ip)
L
Linus Torvalds 已提交
217
{
218 219
	struct xfs_mount	*mp = ip->i_mount;
	uint			offset;
L
Linus Torvalds 已提交
220

221
	if (mp->m_sb.sb_inodesize == 256) {
222
		offset = XFS_LITINO(mp, ip->i_d.di_version) -
223 224 225
				XFS_BMDR_SPACE_CALC(MINABTPTRS);
	} else {
		offset = XFS_BMDR_SPACE_CALC(6 * MINABTPTRS);
L
Linus Torvalds 已提交
226
	}
227

228
	ASSERT(offset < XFS_LITINO(mp, ip->i_d.di_version));
229
	return offset;
L
Linus Torvalds 已提交
230 231 232
}

/*
233 234 235
 * Helper routine to reset inode di_forkoff field when switching
 * attribute fork from local to extent format - we reset it where
 * possible to make space available for inline data fork extents.
236 237
 */
STATIC void
238 239 240
xfs_bmap_forkoff_reset(
	xfs_inode_t	*ip,
	int		whichfork)
241
{
242 243 244 245 246 247 248 249 250
	if (whichfork == XFS_ATTR_FORK &&
	    ip->i_d.di_format != XFS_DINODE_FMT_DEV &&
	    ip->i_d.di_format != XFS_DINODE_FMT_UUID &&
	    ip->i_d.di_format != XFS_DINODE_FMT_BTREE) {
		uint	dfl_forkoff = xfs_default_attroffset(ip) >> 3;

		if (dfl_forkoff > ip->i_d.di_forkoff)
			ip->i_d.di_forkoff = dfl_forkoff;
	}
251 252
}

253 254 255 256 257 258 259 260
#ifdef DEBUG
STATIC struct xfs_buf *
xfs_bmap_get_bp(
	struct xfs_btree_cur	*cur,
	xfs_fsblock_t		bno)
{
	struct xfs_log_item_desc *lidp;
	int			i;
261

262 263 264 265 266 267 268 269
	if (!cur)
		return NULL;

	for (i = 0; i < XFS_BTREE_MAXLEVELS; i++) {
		if (!cur->bc_bufs[i])
			break;
		if (XFS_BUF_ADDR(cur->bc_bufs[i]) == bno)
			return cur->bc_bufs[i];
L
Linus Torvalds 已提交
270
	}
271

272 273 274 275 276 277 278 279
	/* Chase down all the log items to see if the bp is there */
	list_for_each_entry(lidp, &cur->bc_tp->t_items, lid_trans) {
		struct xfs_buf_log_item	*bip;
		bip = (struct xfs_buf_log_item *)lidp->lid_item;
		if (bip->bli_item.li_type == XFS_LI_BUF &&
		    XFS_BUF_ADDR(bip->bli_buf) == bno)
			return bip->bli_buf;
	}
280

281 282
	return NULL;
}
C
Christoph Hellwig 已提交
283

284 285 286 287 288 289 290 291 292 293
STATIC void
xfs_check_block(
	struct xfs_btree_block	*block,
	xfs_mount_t		*mp,
	int			root,
	short			sz)
{
	int			i, j, dmxr;
	__be64			*pp, *thispa;	/* pointer to block address */
	xfs_bmbt_key_t		*prevp, *keyp;
L
Linus Torvalds 已提交
294

295
	ASSERT(be16_to_cpu(block->bb_level) > 0);
C
Christoph Hellwig 已提交
296

297 298 299 300
	prevp = NULL;
	for( i = 1; i <= xfs_btree_get_numrecs(block); i++) {
		dmxr = mp->m_bmap_dmxr[0];
		keyp = XFS_BMBT_KEY_ADDR(mp, block, i);
C
Christoph Hellwig 已提交
301

302 303 304
		if (prevp) {
			ASSERT(be64_to_cpu(prevp->br_startoff) <
			       be64_to_cpu(keyp->br_startoff));
L
Linus Torvalds 已提交
305
		}
306
		prevp = keyp;
L
Linus Torvalds 已提交
307 308

		/*
309
		 * Compare the block numbers to see if there are dups.
L
Linus Torvalds 已提交
310
		 */
311 312 313 314
		if (root)
			pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, i, sz);
		else
			pp = XFS_BMBT_PTR_ADDR(mp, block, i, dmxr);
C
Christoph Hellwig 已提交
315

316 317 318 319 320 321 322 323 324 325 326 327
		for (j = i+1; j <= be16_to_cpu(block->bb_numrecs); j++) {
			if (root)
				thispa = XFS_BMAP_BROOT_PTR_ADDR(mp, block, j, sz);
			else
				thispa = XFS_BMBT_PTR_ADDR(mp, block, j, dmxr);
			if (*thispa == *pp) {
				xfs_warn(mp, "%s: thispa(%d) == pp(%d) %Ld",
					__func__, j, i,
					(unsigned long long)be64_to_cpu(*thispa));
				panic("%s: ptrs are equal in node\n",
					__func__);
			}
L
Linus Torvalds 已提交
328
		}
329 330
	}
}
L
Linus Torvalds 已提交
331

332 333
/*
 * Check that the extents for the inode ip are in the right order in all
334 335 336 337
 * btree leaves. THis becomes prohibitively expensive for large extent count
 * files, so don't bother with inodes that have more than 10,000 extents in
 * them. The btree record ordering checks will still be done, so for such large
 * bmapbt constructs that is going to catch most corruptions.
338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362
 */
STATIC void
xfs_bmap_check_leaf_extents(
	xfs_btree_cur_t		*cur,	/* btree cursor or null */
	xfs_inode_t		*ip,		/* incore inode pointer */
	int			whichfork)	/* data or attr fork */
{
	struct xfs_btree_block	*block;	/* current btree block */
	xfs_fsblock_t		bno;	/* block # of "block" */
	xfs_buf_t		*bp;	/* buffer for "block" */
	int			error;	/* error return value */
	xfs_extnum_t		i=0, j;	/* index into the extents list */
	xfs_ifork_t		*ifp;	/* fork structure */
	int			level;	/* btree level, for checking */
	xfs_mount_t		*mp;	/* file system mount structure */
	__be64			*pp;	/* pointer to block address */
	xfs_bmbt_rec_t		*ep;	/* pointer to current extent */
	xfs_bmbt_rec_t		last = {0, 0}; /* last extent in prev block */
	xfs_bmbt_rec_t		*nextp;	/* pointer to next extent */
	int			bp_release = 0;

	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE) {
		return;
	}

363 364 365 366
	/* skip large extent count inodes */
	if (ip->i_d.di_nextents > 10000)
		return;

367 368 369 370 371 372 373 374 375 376 377 378 379
	bno = NULLFSBLOCK;
	mp = ip->i_mount;
	ifp = XFS_IFORK_PTR(ip, whichfork);
	block = ifp->if_broot;
	/*
	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
	 */
	level = be16_to_cpu(block->bb_level);
	ASSERT(level > 0);
	xfs_check_block(block, mp, 1, ifp->if_broot_bytes);
	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
	bno = be64_to_cpu(*pp);

C
Christoph Hellwig 已提交
380
	ASSERT(bno != NULLFSBLOCK);
381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396
	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);

	/*
	 * Go down the tree until leaf level is reached, following the first
	 * pointer (leftmost) at each level.
	 */
	while (level-- > 0) {
		/* See if buf is in cur first */
		bp_release = 0;
		bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
		if (!bp) {
			bp_release = 1;
			error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
						XFS_BMAP_BTREE_REF,
						&xfs_bmbt_buf_ops);
397
			if (error)
398
				goto error_norelse;
L
Linus Torvalds 已提交
399
		}
400 401 402
		block = XFS_BUF_TO_BLOCK(bp);
		if (level == 0)
			break;
L
Linus Torvalds 已提交
403 404

		/*
405 406
		 * Check this block for basic sanity (increasing keys and
		 * no duplicate blocks).
L
Linus Torvalds 已提交
407
		 */
C
Christoph Hellwig 已提交
408

409 410 411
		xfs_check_block(block, mp, 0, 0);
		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
		bno = be64_to_cpu(*pp);
412 413
		XFS_WANT_CORRUPTED_GOTO(mp,
					XFS_FSB_SANITY_CHECK(mp, bno), error0);
414 415 416
		if (bp_release) {
			bp_release = 0;
			xfs_trans_brelse(NULL, bp);
L
Linus Torvalds 已提交
417
		}
418
	}
C
Christoph Hellwig 已提交
419

420 421 422 423 424 425 426 427 428 429 430 431 432 433
	/*
	 * Here with bp and block set to the leftmost leaf node in the tree.
	 */
	i = 0;

	/*
	 * Loop over all leaf nodes checking that all extents are in the right order.
	 */
	for (;;) {
		xfs_fsblock_t	nextbno;
		xfs_extnum_t	num_recs;


		num_recs = xfs_btree_get_numrecs(block);
L
Linus Torvalds 已提交
434 435

		/*
436
		 * Read-ahead the next leaf block, if any.
L
Linus Torvalds 已提交
437
		 */
438

439
		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
L
Linus Torvalds 已提交
440 441

		/*
442 443 444
		 * Check all the extents to make sure they are OK.
		 * If we had a previous block, the last entry should
		 * conform with the first entry in this one.
L
Linus Torvalds 已提交
445
		 */
C
Christoph Hellwig 已提交
446

447 448 449 450 451 452 453 454 455 456 457 458 459
		ep = XFS_BMBT_REC_ADDR(mp, block, 1);
		if (i) {
			ASSERT(xfs_bmbt_disk_get_startoff(&last) +
			       xfs_bmbt_disk_get_blockcount(&last) <=
			       xfs_bmbt_disk_get_startoff(ep));
		}
		for (j = 1; j < num_recs; j++) {
			nextp = XFS_BMBT_REC_ADDR(mp, block, j + 1);
			ASSERT(xfs_bmbt_disk_get_startoff(ep) +
			       xfs_bmbt_disk_get_blockcount(ep) <=
			       xfs_bmbt_disk_get_startoff(nextp));
			ep = nextp;
		}
L
Linus Torvalds 已提交
460

461 462 463 464 465 466 467
		last = *ep;
		i += num_recs;
		if (bp_release) {
			bp_release = 0;
			xfs_trans_brelse(NULL, bp);
		}
		bno = nextbno;
L
Linus Torvalds 已提交
468
		/*
469
		 * If we've reached the end, stop.
L
Linus Torvalds 已提交
470
		 */
471 472
		if (bno == NULLFSBLOCK)
			break;
473

474 475 476 477 478 479 480
		bp_release = 0;
		bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
		if (!bp) {
			bp_release = 1;
			error = xfs_btree_read_bufl(mp, NULL, bno, 0, &bp,
						XFS_BMAP_BTREE_REF,
						&xfs_bmbt_buf_ops);
481
			if (error)
482
				goto error_norelse;
L
Linus Torvalds 已提交
483
		}
484
		block = XFS_BUF_TO_BLOCK(bp);
485
	}
486

487
	return;
488

489 490 491 492 493 494 495 496 497
error0:
	xfs_warn(mp, "%s: at error0", __func__);
	if (bp_release)
		xfs_trans_brelse(NULL, bp);
error_norelse:
	xfs_warn(mp, "%s: BAD after btree leaves for %d extents",
		__func__, i);
	panic("%s: CORRUPTED BTREE OR SOMETHING", __func__);
	return;
L
Linus Torvalds 已提交
498 499 500
}

/*
501
 * Add bmap trace insert entries for all the contents of the extent records.
L
Linus Torvalds 已提交
502
 */
503 504 505 506 507 508
void
xfs_bmap_trace_exlist(
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_extnum_t	cnt,		/* count of entries in the list */
	int		whichfork,	/* data or attr fork */
	unsigned long	caller_ip)
L
Linus Torvalds 已提交
509
{
510 511 512
	xfs_extnum_t	idx;		/* extent record index */
	xfs_ifork_t	*ifp;		/* inode fork pointer */
	int		state = 0;
513

514 515
	if (whichfork == XFS_ATTR_FORK)
		state |= BMAP_ATTRFORK;
516

517 518 519 520 521
	ifp = XFS_IFORK_PTR(ip, whichfork);
	ASSERT(cnt == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
	for (idx = 0; idx < cnt; idx++)
		trace_xfs_extlist(ip, idx, whichfork, caller_ip);
}
522

523 524
/*
 * Validate that the bmbt_irecs being returned from bmapi are valid
525 526
 * given the caller's original parameters.  Specifically check the
 * ranges of the returned irecs to ensure that they only extend beyond
527 528 529 530 531 532 533 534 535 536 537 538
 * the given parameters if the XFS_BMAPI_ENTIRE flag was set.
 */
STATIC void
xfs_bmap_validate_ret(
	xfs_fileoff_t		bno,
	xfs_filblks_t		len,
	int			flags,
	xfs_bmbt_irec_t		*mval,
	int			nmap,
	int			ret_nmap)
{
	int			i;		/* index to map values */
539

540
	ASSERT(ret_nmap <= nmap);
541

542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562
	for (i = 0; i < ret_nmap; i++) {
		ASSERT(mval[i].br_blockcount > 0);
		if (!(flags & XFS_BMAPI_ENTIRE)) {
			ASSERT(mval[i].br_startoff >= bno);
			ASSERT(mval[i].br_blockcount <= len);
			ASSERT(mval[i].br_startoff + mval[i].br_blockcount <=
			       bno + len);
		} else {
			ASSERT(mval[i].br_startoff < bno + len);
			ASSERT(mval[i].br_startoff + mval[i].br_blockcount >
			       bno);
		}
		ASSERT(i == 0 ||
		       mval[i - 1].br_startoff + mval[i - 1].br_blockcount ==
		       mval[i].br_startoff);
		ASSERT(mval[i].br_startblock != DELAYSTARTBLOCK &&
		       mval[i].br_startblock != HOLESTARTBLOCK);
		ASSERT(mval[i].br_state == XFS_EXT_NORM ||
		       mval[i].br_state == XFS_EXT_UNWRITTEN);
	}
}
563

564 565 566 567
#else
#define xfs_bmap_check_leaf_extents(cur, ip, whichfork)		do { } while (0)
#define	xfs_bmap_validate_ret(bno,len,flags,mval,onmap,nmap)
#endif /* DEBUG */
568

569 570 571
/*
 * bmap free list manipulation functions
 */
572

573 574 575 576 577 578
/*
 * Add the extent to the list of extents to be free at transaction end.
 * The list is maintained sorted (by block number).
 */
void
xfs_bmap_add_free(
579 580 581 582 583
	struct xfs_mount		*mp,
	struct xfs_defer_ops		*dfops,
	xfs_fsblock_t			bno,
	xfs_filblks_t			len,
	struct xfs_owner_info		*oinfo)
584
{
585
	struct xfs_extent_free_item	*new;		/* new element */
586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601
#ifdef DEBUG
	xfs_agnumber_t		agno;
	xfs_agblock_t		agbno;

	ASSERT(bno != NULLFSBLOCK);
	ASSERT(len > 0);
	ASSERT(len <= MAXEXTLEN);
	ASSERT(!isnullstartblock(bno));
	agno = XFS_FSB_TO_AGNO(mp, bno);
	agbno = XFS_FSB_TO_AGBNO(mp, bno);
	ASSERT(agno < mp->m_sb.sb_agcount);
	ASSERT(agbno < mp->m_sb.sb_agblocks);
	ASSERT(len < mp->m_sb.sb_agblocks);
	ASSERT(agbno + len <= mp->m_sb.sb_agblocks);
#endif
	ASSERT(xfs_bmap_free_item_zone != NULL);
602

603
	new = kmem_zone_alloc(xfs_bmap_free_item_zone, KM_SLEEP);
604 605
	new->xefi_startblock = bno;
	new->xefi_blockcount = (xfs_extlen_t)len;
606 607 608 609
	if (oinfo)
		new->xefi_oinfo = *oinfo;
	else
		xfs_rmap_skip_owner_update(&new->xefi_oinfo);
610 611
	trace_xfs_bmap_free_defer(mp, XFS_FSB_TO_AGNO(mp, bno), 0,
			XFS_FSB_TO_AGBNO(mp, bno), len);
612
	xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_FREE, &new->xefi_list);
613
}
C
Christoph Hellwig 已提交
614

615 616 617
/*
 * Inode fork format manipulation functions
 */
L
Linus Torvalds 已提交
618

619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641
/*
 * Transform a btree format file with only one leaf node, where the
 * extents list will fit in the inode, into an extents format file.
 * Since the file extents are already in-core, all we have to do is
 * give up the space for the btree root and pitch the leaf block.
 */
STATIC int				/* error */
xfs_bmap_btree_to_extents(
	xfs_trans_t		*tp,	/* transaction pointer */
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_btree_cur_t		*cur,	/* btree cursor */
	int			*logflagsp, /* inode logging flags */
	int			whichfork)  /* data or attr fork */
{
	/* REFERENCED */
	struct xfs_btree_block	*cblock;/* child btree block */
	xfs_fsblock_t		cbno;	/* child block number */
	xfs_buf_t		*cbp;	/* child block's buffer */
	int			error;	/* error return value */
	xfs_ifork_t		*ifp;	/* inode fork data */
	xfs_mount_t		*mp;	/* mount point structure */
	__be64			*pp;	/* ptr to block address */
	struct xfs_btree_block	*rblock;/* root btree block */
642
	struct xfs_owner_info	oinfo;
L
Linus Torvalds 已提交
643

644 645
	mp = ip->i_mount;
	ifp = XFS_IFORK_PTR(ip, whichfork);
646
	ASSERT(whichfork != XFS_COW_FORK);
647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666
	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
	rblock = ifp->if_broot;
	ASSERT(be16_to_cpu(rblock->bb_level) == 1);
	ASSERT(be16_to_cpu(rblock->bb_numrecs) == 1);
	ASSERT(xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0) == 1);
	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, ifp->if_broot_bytes);
	cbno = be64_to_cpu(*pp);
	*logflagsp = 0;
#ifdef DEBUG
	if ((error = xfs_btree_check_lptr(cur, cbno, 1)))
		return error;
#endif
	error = xfs_btree_read_bufl(mp, tp, cbno, 0, &cbp, XFS_BMAP_BTREE_REF,
				&xfs_bmbt_buf_ops);
	if (error)
		return error;
	cblock = XFS_BUF_TO_BLOCK(cbp);
	if ((error = xfs_btree_check_block(cur, cblock, 0, cbp)))
		return error;
667 668
	xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, whichfork);
	xfs_bmap_add_free(mp, cur->bc_private.b.dfops, cbno, 1, &oinfo);
669 670 671 672 673 674 675 676 677 678 679 680
	ip->i_d.di_nblocks--;
	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
	xfs_trans_binval(tp, cbp);
	if (cur->bc_bufs[0] == cbp)
		cur->bc_bufs[0] = NULL;
	xfs_iroot_realloc(ip, -1, whichfork);
	ASSERT(ifp->if_broot == NULL);
	ASSERT((ifp->if_flags & XFS_IFBROOT) == 0);
	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
	*logflagsp = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
	return 0;
}
C
Christoph Hellwig 已提交
681

682 683 684 685 686 687 688 689 690
/*
 * Convert an extents-format file into a btree-format file.
 * The new file will have a root block (in the inode) and a single child block.
 */
STATIC int					/* error */
xfs_bmap_extents_to_btree(
	xfs_trans_t		*tp,		/* transaction pointer */
	xfs_inode_t		*ip,		/* incore inode pointer */
	xfs_fsblock_t		*firstblock,	/* first-block-allocated */
691
	struct xfs_defer_ops	*dfops,		/* blocks freed in xaction */
692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710
	xfs_btree_cur_t		**curp,		/* cursor returned to caller */
	int			wasdel,		/* converting a delayed alloc */
	int			*logflagsp,	/* inode logging flags */
	int			whichfork)	/* data or attr fork */
{
	struct xfs_btree_block	*ablock;	/* allocated (child) bt block */
	xfs_buf_t		*abp;		/* buffer for ablock */
	xfs_alloc_arg_t		args;		/* allocation arguments */
	xfs_bmbt_rec_t		*arp;		/* child record pointer */
	struct xfs_btree_block	*block;		/* btree root block */
	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
	xfs_bmbt_rec_host_t	*ep;		/* extent record pointer */
	int			error;		/* error return value */
	xfs_extnum_t		i, cnt;		/* extent record index */
	xfs_ifork_t		*ifp;		/* inode fork pointer */
	xfs_bmbt_key_t		*kp;		/* root block key pointer */
	xfs_mount_t		*mp;		/* mount structure */
	xfs_extnum_t		nextents;	/* number of file extents */
	xfs_bmbt_ptr_t		*pp;		/* root block address pointer */
L
Linus Torvalds 已提交
711

712
	mp = ip->i_mount;
713
	ASSERT(whichfork != XFS_COW_FORK);
714 715
	ifp = XFS_IFORK_PTR(ip, whichfork);
	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS);
C
Christoph Hellwig 已提交
716

717 718 719 720 721
	/*
	 * Make space in the inode incore.
	 */
	xfs_iroot_realloc(ip, 1, whichfork);
	ifp->if_flags |= XFS_IFBROOT;
C
Christoph Hellwig 已提交
722

723 724 725 726
	/*
	 * Fill in the root.
	 */
	block = ifp->if_broot;
727 728 729 730 731 732 733 734
	if (xfs_sb_version_hascrc(&mp->m_sb))
		xfs_btree_init_block_int(mp, block, XFS_BUF_DADDR_NULL,
				 XFS_BMAP_CRC_MAGIC, 1, 1, ip->i_ino,
				 XFS_BTREE_LONG_PTRS | XFS_BTREE_CRC_BLOCKS);
	else
		xfs_btree_init_block_int(mp, block, XFS_BUF_DADDR_NULL,
				 XFS_BMAP_MAGIC, 1, 1, ip->i_ino,
				 XFS_BTREE_LONG_PTRS);
C
Christoph Hellwig 已提交
735

736 737 738 739 740
	/*
	 * Need a cursor.  Can't allocate until bb_level is filled in.
	 */
	cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
	cur->bc_private.b.firstblock = *firstblock;
741
	cur->bc_private.b.dfops = dfops;
742 743 744 745 746 747 748 749
	cur->bc_private.b.flags = wasdel ? XFS_BTCUR_BPRV_WASDEL : 0;
	/*
	 * Convert to a btree with two levels, one record in root.
	 */
	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_BTREE);
	memset(&args, 0, sizeof(args));
	args.tp = tp;
	args.mp = mp;
750
	xfs_rmap_ino_bmbt_owner(&args.oinfo, ip->i_ino, whichfork);
751 752 753 754
	args.firstblock = *firstblock;
	if (*firstblock == NULLFSBLOCK) {
		args.type = XFS_ALLOCTYPE_START_BNO;
		args.fsbno = XFS_INO_TO_FSB(mp, ip->i_ino);
755
	} else if (dfops->dop_low) {
756
try_another_ag:
757 758 759 760 761 762 763 764 765 766 767 768 769 770
		args.type = XFS_ALLOCTYPE_START_BNO;
		args.fsbno = *firstblock;
	} else {
		args.type = XFS_ALLOCTYPE_NEAR_BNO;
		args.fsbno = *firstblock;
	}
	args.minlen = args.maxlen = args.prod = 1;
	args.wasdel = wasdel;
	*logflagsp = 0;
	if ((error = xfs_alloc_vextent(&args))) {
		xfs_iroot_realloc(ip, -1, whichfork);
		xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
		return error;
	}
771 772 773 774 775 776 777 778 779 780 781 782 783 784 785

	/*
	 * During a CoW operation, the allocation and bmbt updates occur in
	 * different transactions.  The mapping code tries to put new bmbt
	 * blocks near extents being mapped, but the only way to guarantee this
	 * is if the alloc and the mapping happen in a single transaction that
	 * has a block reservation.  That isn't the case here, so if we run out
	 * of space we'll try again with another AG.
	 */
	if (xfs_sb_version_hasreflink(&cur->bc_mp->m_sb) &&
	    args.fsbno == NULLFSBLOCK &&
	    args.type == XFS_ALLOCTYPE_NEAR_BNO) {
		dfops->dop_low = true;
		goto try_another_ag;
	}
786 787 788 789 790 791
	/*
	 * Allocation can't fail, the space was reserved.
	 */
	ASSERT(args.fsbno != NULLFSBLOCK);
	ASSERT(*firstblock == NULLFSBLOCK ||
	       args.agno == XFS_FSB_TO_AGNO(mp, *firstblock) ||
792
	       (dfops->dop_low &&
793 794 795 796 797 798 799 800 801 802 803
		args.agno > XFS_FSB_TO_AGNO(mp, *firstblock)));
	*firstblock = cur->bc_private.b.firstblock = args.fsbno;
	cur->bc_private.b.allocated++;
	ip->i_d.di_nblocks++;
	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, 1L);
	abp = xfs_btree_get_bufl(mp, tp, args.fsbno, 0);
	/*
	 * Fill in the child block.
	 */
	abp->b_ops = &xfs_bmbt_buf_ops;
	ablock = XFS_BUF_TO_BLOCK(abp);
804 805 806 807 808 809 810 811 812
	if (xfs_sb_version_hascrc(&mp->m_sb))
		xfs_btree_init_block_int(mp, ablock, abp->b_bn,
				XFS_BMAP_CRC_MAGIC, 0, 0, ip->i_ino,
				XFS_BTREE_LONG_PTRS | XFS_BTREE_CRC_BLOCKS);
	else
		xfs_btree_init_block_int(mp, ablock, abp->b_bn,
				XFS_BMAP_MAGIC, 0, 0, ip->i_ino,
				XFS_BTREE_LONG_PTRS);

813 814 815 816 817 818 819 820
	arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
	for (cnt = i = 0; i < nextents; i++) {
		ep = xfs_iext_get_ext(ifp, i);
		if (!isnullstartblock(xfs_bmbt_get_startblock(ep))) {
			arp->l0 = cpu_to_be64(ep->l0);
			arp->l1 = cpu_to_be64(ep->l1);
			arp++; cnt++;
L
Linus Torvalds 已提交
821
		}
822 823 824
	}
	ASSERT(cnt == XFS_IFORK_NEXTENTS(ip, whichfork));
	xfs_btree_set_numrecs(ablock, cnt);
L
Linus Torvalds 已提交
825

826 827 828 829 830 831 832 833 834
	/*
	 * Fill in the root key and pointer.
	 */
	kp = XFS_BMBT_KEY_ADDR(mp, block, 1);
	arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
	kp->br_startoff = cpu_to_be64(xfs_bmbt_disk_get_startoff(arp));
	pp = XFS_BMBT_PTR_ADDR(mp, block, 1, xfs_bmbt_get_maxrecs(cur,
						be16_to_cpu(block->bb_level)));
	*pp = cpu_to_be64(args.fsbno);
C
Christoph Hellwig 已提交
835

836 837 838 839 840 841 842 843 844 845 846
	/*
	 * Do all this logging at the end so that
	 * the root is at the right level.
	 */
	xfs_btree_log_block(cur, abp, XFS_BB_ALL_BITS);
	xfs_btree_log_recs(cur, abp, 1, be16_to_cpu(ablock->bb_numrecs));
	ASSERT(*curp == NULL);
	*curp = cur;
	*logflagsp = XFS_ILOG_CORE | xfs_ilog_fbroot(whichfork);
	return 0;
}
C
Christoph Hellwig 已提交
847

848 849 850 851 852 853
/*
 * Convert a local file to an extents file.
 * This code is out of bounds for data forks of regular files,
 * since the file data needs to get logged so things will stay consistent.
 * (The bmap-level manipulations are ok, though).
 */
854 855 856 857 858 859 860
void
xfs_bmap_local_to_extents_empty(
	struct xfs_inode	*ip,
	int			whichfork)
{
	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);

861
	ASSERT(whichfork != XFS_COW_FORK);
862 863 864 865
	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
	ASSERT(ifp->if_bytes == 0);
	ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) == 0);

866
	xfs_bmap_forkoff_reset(ip, whichfork);
867 868 869 870 871 872
	ifp->if_flags &= ~XFS_IFINLINE;
	ifp->if_flags |= XFS_IFEXTENTS;
	XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS);
}


873 874 875 876 877 878 879 880
STATIC int				/* error */
xfs_bmap_local_to_extents(
	xfs_trans_t	*tp,		/* transaction pointer */
	xfs_inode_t	*ip,		/* incore inode pointer */
	xfs_fsblock_t	*firstblock,	/* first block allocated in xaction */
	xfs_extlen_t	total,		/* total blocks needed by transaction */
	int		*logflagsp,	/* inode logging flags */
	int		whichfork,
881 882
	void		(*init_fn)(struct xfs_trans *tp,
				   struct xfs_buf *bp,
883 884 885
				   struct xfs_inode *ip,
				   struct xfs_ifork *ifp))
{
886
	int		error = 0;
887 888
	int		flags;		/* logging flags returned */
	xfs_ifork_t	*ifp;		/* inode fork pointer */
889 890 891
	xfs_alloc_arg_t	args;		/* allocation arguments */
	xfs_buf_t	*bp;		/* buffer for extent block */
	xfs_bmbt_rec_host_t *ep;	/* extent record pointer */
C
Christoph Hellwig 已提交
892

893 894 895 896
	/*
	 * We don't want to deal with the case of keeping inode data inline yet.
	 * So sending the data fork of a regular inode is invalid.
	 */
D
Dave Chinner 已提交
897
	ASSERT(!(S_ISREG(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK));
898 899
	ifp = XFS_IFORK_PTR(ip, whichfork);
	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
900 901 902 903 904 905 906

	if (!ifp->if_bytes) {
		xfs_bmap_local_to_extents_empty(ip, whichfork);
		flags = XFS_ILOG_CORE;
		goto done;
	}

907 908
	flags = 0;
	error = 0;
909 910 911 912 913
	ASSERT((ifp->if_flags & (XFS_IFINLINE|XFS_IFEXTENTS|XFS_IFEXTIREC)) ==
								XFS_IFINLINE);
	memset(&args, 0, sizeof(args));
	args.tp = tp;
	args.mp = ip->i_mount;
914
	xfs_rmap_ino_owner(&args.oinfo, ip->i_ino, whichfork, 0);
915 916 917 918 919 920
	args.firstblock = *firstblock;
	/*
	 * Allocate a block.  We know we need only one, since the
	 * file currently fits in an inode.
	 */
	if (*firstblock == NULLFSBLOCK) {
921
try_another_ag:
922 923
		args.fsbno = XFS_INO_TO_FSB(args.mp, ip->i_ino);
		args.type = XFS_ALLOCTYPE_START_BNO;
924
	} else {
925 926
		args.fsbno = *firstblock;
		args.type = XFS_ALLOCTYPE_NEAR_BNO;
927
	}
928 929 930 931 932 933
	args.total = total;
	args.minlen = args.maxlen = args.prod = 1;
	error = xfs_alloc_vextent(&args);
	if (error)
		goto done;

934 935 936 937 938 939 940 941 942 943 944 945 946
	/*
	 * During a CoW operation, the allocation and bmbt updates occur in
	 * different transactions.  The mapping code tries to put new bmbt
	 * blocks near extents being mapped, but the only way to guarantee this
	 * is if the alloc and the mapping happen in a single transaction that
	 * has a block reservation.  That isn't the case here, so if we run out
	 * of space we'll try again with another AG.
	 */
	if (xfs_sb_version_hasreflink(&ip->i_mount->m_sb) &&
	    args.fsbno == NULLFSBLOCK &&
	    args.type == XFS_ALLOCTYPE_NEAR_BNO) {
		goto try_another_ag;
	}
947 948 949 950 951 952
	/* Can't fail, the space was reserved. */
	ASSERT(args.fsbno != NULLFSBLOCK);
	ASSERT(args.len == 1);
	*firstblock = args.fsbno;
	bp = xfs_btree_get_bufl(args.mp, tp, args.fsbno, 0);

953
	/*
954
	 * Initialize the block, copy the data and log the remote buffer.
955
	 *
956 957 958 959
	 * The callout is responsible for logging because the remote format
	 * might differ from the local format and thus we don't know how much to
	 * log here. Note that init_fn must also set the buffer log item type
	 * correctly.
960
	 */
961 962
	init_fn(tp, bp, ip, ifp);

963
	/* account for the change in fork size */
964 965
	xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
	xfs_bmap_local_to_extents_empty(ip, whichfork);
966
	flags |= XFS_ILOG_CORE;
967 968 969 970 971 972 973 974 975 976 977 978 979

	xfs_iext_add(ifp, 0, 1);
	ep = xfs_iext_get_ext(ifp, 0);
	xfs_bmbt_set_allf(ep, 0, args.fsbno, 1, XFS_EXT_NORM);
	trace_xfs_bmap_post_update(ip, 0,
			whichfork == XFS_ATTR_FORK ? BMAP_ATTRFORK : 0,
			_THIS_IP_);
	XFS_IFORK_NEXT_SET(ip, whichfork, 1);
	ip->i_d.di_nblocks = 1;
	xfs_trans_mod_dquot_byino(tp, ip,
		XFS_TRANS_DQ_BCOUNT, 1L);
	flags |= xfs_ilog_fext(whichfork);

980 981 982 983
done:
	*logflagsp = flags;
	return error;
}
C
Christoph Hellwig 已提交
984

985 986 987 988 989 990 991 992
/*
 * Called from xfs_bmap_add_attrfork to handle btree format files.
 */
STATIC int					/* error */
xfs_bmap_add_attrfork_btree(
	xfs_trans_t		*tp,		/* transaction pointer */
	xfs_inode_t		*ip,		/* incore inode pointer */
	xfs_fsblock_t		*firstblock,	/* first block allocated */
993
	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
994 995 996 997 998 999
	int			*flags)		/* inode logging flags */
{
	xfs_btree_cur_t		*cur;		/* btree cursor */
	int			error;		/* error return value */
	xfs_mount_t		*mp;		/* file system mount struct */
	int			stat;		/* newroot status */
C
Christoph Hellwig 已提交
1000

1001 1002 1003 1004 1005
	mp = ip->i_mount;
	if (ip->i_df.if_broot_bytes <= XFS_IFORK_DSIZE(ip))
		*flags |= XFS_ILOG_DBROOT;
	else {
		cur = xfs_bmbt_init_cursor(mp, tp, ip, XFS_DATA_FORK);
1006
		cur->bc_private.b.dfops = dfops;
1007 1008 1009 1010
		cur->bc_private.b.firstblock = *firstblock;
		if ((error = xfs_bmbt_lookup_ge(cur, 0, 0, 0, &stat)))
			goto error0;
		/* must be at least one entry */
1011
		XFS_WANT_CORRUPTED_GOTO(mp, stat == 1, error0);
1012 1013 1014 1015
		if ((error = xfs_btree_new_iroot(cur, flags, &stat)))
			goto error0;
		if (stat == 0) {
			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
D
Dave Chinner 已提交
1016
			return -ENOSPC;
L
Linus Torvalds 已提交
1017
		}
1018 1019 1020
		*firstblock = cur->bc_private.b.firstblock;
		cur->bc_private.b.allocated = 0;
		xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
L
Linus Torvalds 已提交
1021
	}
1022 1023 1024 1025 1026
	return 0;
error0:
	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
	return error;
}
1027

1028 1029 1030 1031 1032 1033 1034 1035
/*
 * Called from xfs_bmap_add_attrfork to handle extents format files.
 */
STATIC int					/* error */
xfs_bmap_add_attrfork_extents(
	xfs_trans_t		*tp,		/* transaction pointer */
	xfs_inode_t		*ip,		/* incore inode pointer */
	xfs_fsblock_t		*firstblock,	/* first block allocated */
1036
	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
1037 1038 1039 1040
	int			*flags)		/* inode logging flags */
{
	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
	int			error;		/* error return value */
1041

1042 1043 1044
	if (ip->i_d.di_nextents * sizeof(xfs_bmbt_rec_t) <= XFS_IFORK_DSIZE(ip))
		return 0;
	cur = NULL;
1045
	error = xfs_bmap_extents_to_btree(tp, ip, firstblock, dfops, &cur, 0,
1046
		flags, XFS_DATA_FORK);
1047 1048
	if (cur) {
		cur->bc_private.b.allocated = 0;
1049 1050
		xfs_btree_del_cursor(cur,
			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
1051
	}
L
Linus Torvalds 已提交
1052 1053 1054
	return error;
}

1055 1056 1057 1058 1059 1060 1061 1062 1063
/*
 * Called from xfs_bmap_add_attrfork to handle local format files. Each
 * different data fork content type needs a different callout to do the
 * conversion. Some are basic and only require special block initialisation
 * callouts for the data formating, others (directories) are so specialised they
 * handle everything themselves.
 *
 * XXX (dgc): investigate whether directory conversion can use the generic
 * formatting callout. It should be possible - it's just a very complex
1064
 * formatter.
1065 1066 1067 1068 1069 1070
 */
STATIC int					/* error */
xfs_bmap_add_attrfork_local(
	xfs_trans_t		*tp,		/* transaction pointer */
	xfs_inode_t		*ip,		/* incore inode pointer */
	xfs_fsblock_t		*firstblock,	/* first block allocated */
1071
	struct xfs_defer_ops	*dfops,		/* blocks to free at commit */
1072 1073 1074
	int			*flags)		/* inode logging flags */
{
	xfs_da_args_t		dargs;		/* args for dir/attr code */
1075

1076 1077
	if (ip->i_df.if_bytes <= XFS_IFORK_DSIZE(ip))
		return 0;
1078

D
Dave Chinner 已提交
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 1083
		dargs.dp = ip;
		dargs.firstblock = firstblock;
1084
		dargs.dfops = dfops;
1085
		dargs.total = dargs.geo->fsbcount;
1086 1087 1088
		dargs.whichfork = XFS_DATA_FORK;
		dargs.trans = tp;
		return xfs_dir2_sf_to_block(&dargs);
L
Linus Torvalds 已提交
1089
	}
1090

D
Dave Chinner 已提交
1091
	if (S_ISLNK(VFS_I(ip)->i_mode))
1092 1093 1094
		return xfs_bmap_local_to_extents(tp, ip, firstblock, 1,
						 flags, XFS_DATA_FORK,
						 xfs_symlink_local_to_remote);
1095

1096 1097
	/* should only be called for types that support local format data */
	ASSERT(0);
D
Dave Chinner 已提交
1098
	return -EFSCORRUPTED;
1099
}
C
Christoph Hellwig 已提交
1100

1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111
/*
 * Convert inode from non-attributed to attributed.
 * Must not be in a transaction, ip must not be locked.
 */
int						/* error code */
xfs_bmap_add_attrfork(
	xfs_inode_t		*ip,		/* incore inode pointer */
	int			size,		/* space new attribute needs */
	int			rsvd)		/* xact may use reserved blks */
{
	xfs_fsblock_t		firstblock;	/* 1st block/ag allocated */
1112
	struct xfs_defer_ops	dfops;		/* freed extent records */
1113 1114 1115 1116 1117 1118
	xfs_mount_t		*mp;		/* mount structure */
	xfs_trans_t		*tp;		/* transaction pointer */
	int			blks;		/* space reservation */
	int			version = 1;	/* superblock attr version */
	int			logflags;	/* logging flags */
	int			error;		/* error return value */
C
Christoph Hellwig 已提交
1119

1120
	ASSERT(XFS_IFORK_Q(ip) == 0);
L
Linus Torvalds 已提交
1121

1122 1123
	mp = ip->i_mount;
	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1124

1125
	blks = XFS_ADDAFORK_SPACE_RES(mp);
1126 1127 1128 1129

	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_addafork, blks, 0,
			rsvd ? XFS_TRANS_RESERVE : 0, &tp);
	if (error)
1130
		return error;
1131

1132 1133 1134 1135
	xfs_ilock(ip, XFS_ILOCK_EXCL);
	error = xfs_trans_reserve_quota_nblks(tp, ip, blks, 0, rsvd ?
			XFS_QMOPT_RES_REGBLKS | XFS_QMOPT_FORCE_RES :
			XFS_QMOPT_RES_REGBLKS);
1136 1137
	if (error)
		goto trans_cancel;
1138
	if (XFS_IFORK_Q(ip))
1139
		goto trans_cancel;
1140
	if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS) {
L
Linus Torvalds 已提交
1141
		/*
1142
		 * For inodes coming from pre-6.2 filesystems.
L
Linus Torvalds 已提交
1143
		 */
1144 1145 1146 1147
		ASSERT(ip->i_d.di_aformat == 0);
		ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
	}
	ASSERT(ip->i_d.di_anextents == 0);
C
Christoph Hellwig 已提交
1148

1149
	xfs_trans_ijoin(tp, ip, 0);
1150
	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
L
Linus Torvalds 已提交
1151

1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166
	switch (ip->i_d.di_format) {
	case XFS_DINODE_FMT_DEV:
		ip->i_d.di_forkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
		break;
	case XFS_DINODE_FMT_UUID:
		ip->i_d.di_forkoff = roundup(sizeof(uuid_t), 8) >> 3;
		break;
	case XFS_DINODE_FMT_LOCAL:
	case XFS_DINODE_FMT_EXTENTS:
	case XFS_DINODE_FMT_BTREE:
		ip->i_d.di_forkoff = xfs_attr_shortform_bytesfit(ip, size);
		if (!ip->i_d.di_forkoff)
			ip->i_d.di_forkoff = xfs_default_attroffset(ip) >> 3;
		else if (mp->m_flags & XFS_MOUNT_ATTR2)
			version = 2;
L
Linus Torvalds 已提交
1167
		break;
1168 1169
	default:
		ASSERT(0);
D
Dave Chinner 已提交
1170
		error = -EINVAL;
1171
		goto trans_cancel;
1172
	}
L
Linus Torvalds 已提交
1173

1174 1175 1176 1177
	ASSERT(ip->i_afp == NULL);
	ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP);
	ip->i_afp->if_flags = XFS_IFEXTENTS;
	logflags = 0;
1178
	xfs_defer_init(&dfops, &firstblock);
1179 1180
	switch (ip->i_d.di_format) {
	case XFS_DINODE_FMT_LOCAL:
1181
		error = xfs_bmap_add_attrfork_local(tp, ip, &firstblock, &dfops,
1182 1183 1184 1185
			&logflags);
		break;
	case XFS_DINODE_FMT_EXTENTS:
		error = xfs_bmap_add_attrfork_extents(tp, ip, &firstblock,
1186
			&dfops, &logflags);
1187 1188
		break;
	case XFS_DINODE_FMT_BTREE:
1189
		error = xfs_bmap_add_attrfork_btree(tp, ip, &firstblock, &dfops,
1190 1191 1192 1193
			&logflags);
		break;
	default:
		error = 0;
L
Linus Torvalds 已提交
1194 1195
		break;
	}
1196 1197 1198
	if (logflags)
		xfs_trans_log_inode(tp, ip, logflags);
	if (error)
1199
		goto bmap_cancel;
1200 1201
	if (!xfs_sb_version_hasattr(&mp->m_sb) ||
	   (!xfs_sb_version_hasattr2(&mp->m_sb) && version == 2)) {
1202
		bool log_sb = false;
1203 1204 1205 1206

		spin_lock(&mp->m_sb_lock);
		if (!xfs_sb_version_hasattr(&mp->m_sb)) {
			xfs_sb_version_addattr(&mp->m_sb);
1207
			log_sb = true;
1208 1209 1210
		}
		if (!xfs_sb_version_hasattr2(&mp->m_sb) && version == 2) {
			xfs_sb_version_addattr2(&mp->m_sb);
1211
			log_sb = true;
1212
		}
1213
		spin_unlock(&mp->m_sb_lock);
1214 1215
		if (log_sb)
			xfs_log_sb(tp);
L
Linus Torvalds 已提交
1216
	}
1217

1218
	error = xfs_defer_finish(&tp, &dfops, NULL);
1219
	if (error)
1220
		goto bmap_cancel;
1221
	error = xfs_trans_commit(tp);
1222 1223 1224 1225
	xfs_iunlock(ip, XFS_ILOCK_EXCL);
	return error;

bmap_cancel:
1226
	xfs_defer_cancel(&dfops);
1227
trans_cancel:
1228
	xfs_trans_cancel(tp);
1229 1230
	xfs_iunlock(ip, XFS_ILOCK_EXCL);
	return error;
L
Linus Torvalds 已提交
1231 1232 1233
}

/*
1234
 * Internal and external extent tree search functions.
L
Linus Torvalds 已提交
1235
 */
1236

1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260
/*
 * Read in the extents to if_extents.
 * All inode fields are set up by caller, we just traverse the btree
 * and copy the records in. If the file system cannot contain unwritten
 * extents, the records are checked for no "state" flags.
 */
int					/* error */
xfs_bmap_read_extents(
	xfs_trans_t		*tp,	/* transaction pointer */
	xfs_inode_t		*ip,	/* incore inode */
	int			whichfork) /* data or attr fork */
{
	struct xfs_btree_block	*block;	/* current btree block */
	xfs_fsblock_t		bno;	/* block # of "block" */
	xfs_buf_t		*bp;	/* buffer for "block" */
	int			error;	/* error return value */
	xfs_exntfmt_t		exntf;	/* XFS_EXTFMT_NOSTATE, if checking */
	xfs_extnum_t		i, j;	/* index into the extents list */
	xfs_ifork_t		*ifp;	/* fork structure */
	int			level;	/* btree level, for checking */
	xfs_mount_t		*mp;	/* file system mount structure */
	__be64			*pp;	/* pointer to block address */
	/* REFERENCED */
	xfs_extnum_t		room;	/* number of entries there's room for */
1261

1262 1263 1264 1265 1266 1267
	bno = NULLFSBLOCK;
	mp = ip->i_mount;
	ifp = XFS_IFORK_PTR(ip, whichfork);
	exntf = (whichfork != XFS_DATA_FORK) ? XFS_EXTFMT_NOSTATE :
					XFS_EXTFMT_INODE(ip);
	block = ifp->if_broot;
L
Linus Torvalds 已提交
1268
	/*
1269
	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
L
Linus Torvalds 已提交
1270
	 */
1271 1272 1273 1274
	level = be16_to_cpu(block->bb_level);
	ASSERT(level > 0);
	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
	bno = be64_to_cpu(*pp);
C
Christoph Hellwig 已提交
1275
	ASSERT(bno != NULLFSBLOCK);
1276 1277
	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
L
Linus Torvalds 已提交
1278
	/*
1279 1280
	 * Go down the tree until leaf level is reached, following the first
	 * pointer (leftmost) at each level.
L
Linus Torvalds 已提交
1281
	 */
1282 1283 1284 1285 1286 1287 1288 1289 1290 1291
	while (level-- > 0) {
		error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
				XFS_BMAP_BTREE_REF, &xfs_bmbt_buf_ops);
		if (error)
			return error;
		block = XFS_BUF_TO_BLOCK(bp);
		if (level == 0)
			break;
		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
		bno = be64_to_cpu(*pp);
1292 1293
		XFS_WANT_CORRUPTED_GOTO(mp,
			XFS_FSB_SANITY_CHECK(mp, bno), error0);
1294
		xfs_trans_brelse(tp, bp);
L
Linus Torvalds 已提交
1295 1296
	}
	/*
1297
	 * Here with bp and block set to the leftmost leaf node in the tree.
L
Linus Torvalds 已提交
1298
	 */
1299 1300
	room = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
	i = 0;
L
Linus Torvalds 已提交
1301
	/*
1302
	 * Loop over all leaf nodes.  Copy information to the extent records.
L
Linus Torvalds 已提交
1303
	 */
1304 1305 1306 1307 1308
	for (;;) {
		xfs_bmbt_rec_t	*frp;
		xfs_fsblock_t	nextbno;
		xfs_extnum_t	num_recs;
		xfs_extnum_t	start;
C
Christoph Hellwig 已提交
1309

1310 1311 1312 1313 1314 1315 1316 1317 1318
		num_recs = xfs_btree_get_numrecs(block);
		if (unlikely(i + num_recs > room)) {
			ASSERT(i + num_recs <= room);
			xfs_warn(ip->i_mount,
				"corrupt dinode %Lu, (btree extents).",
				(unsigned long long) ip->i_ino);
			XFS_CORRUPTION_ERROR("xfs_bmap_read_extents(1)",
				XFS_ERRLEVEL_LOW, ip->i_mount, block);
			goto error0;
L
Linus Torvalds 已提交
1319 1320
		}
		/*
1321
		 * Read-ahead the next leaf block, if any.
L
Linus Torvalds 已提交
1322
		 */
1323 1324 1325 1326
		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
		if (nextbno != NULLFSBLOCK)
			xfs_btree_reada_bufl(mp, nextbno, 1,
					     &xfs_bmbt_buf_ops);
L
Linus Torvalds 已提交
1327
		/*
1328
		 * Copy records into the extent records.
L
Linus Torvalds 已提交
1329
		 */
1330 1331 1332 1333 1334 1335
		frp = XFS_BMBT_REC_ADDR(mp, block, 1);
		start = i;
		for (j = 0; j < num_recs; j++, i++, frp++) {
			xfs_bmbt_rec_host_t *trp = xfs_iext_get_ext(ifp, i);
			trp->l0 = be64_to_cpu(frp->l0);
			trp->l1 = be64_to_cpu(frp->l1);
L
Linus Torvalds 已提交
1336
		}
1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352
		if (exntf == XFS_EXTFMT_NOSTATE) {
			/*
			 * Check all attribute bmap btree records and
			 * any "older" data bmap btree records for a
			 * set bit in the "extent flag" position.
			 */
			if (unlikely(xfs_check_nostate_extents(ifp,
					start, num_recs))) {
				XFS_ERROR_REPORT("xfs_bmap_read_extents(2)",
						 XFS_ERRLEVEL_LOW,
						 ip->i_mount);
				goto error0;
			}
		}
		xfs_trans_brelse(tp, bp);
		bno = nextbno;
L
Linus Torvalds 已提交
1353
		/*
1354
		 * If we've reached the end, stop.
L
Linus Torvalds 已提交
1355
		 */
1356 1357 1358 1359 1360 1361 1362
		if (bno == NULLFSBLOCK)
			break;
		error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
				XFS_BMAP_BTREE_REF, &xfs_bmbt_buf_ops);
		if (error)
			return error;
		block = XFS_BUF_TO_BLOCK(bp);
L
Linus Torvalds 已提交
1363
	}
1364 1365 1366 1367 1368 1369
	ASSERT(i == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)));
	ASSERT(i == XFS_IFORK_NEXTENTS(ip, whichfork));
	XFS_BMAP_TRACE_EXLIST(ip, i, whichfork);
	return 0;
error0:
	xfs_trans_brelse(tp, bp);
D
Dave Chinner 已提交
1370
	return -EFSCORRUPTED;
1371
}
1372 1373


1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391
/*
 * Search the extent records for the entry containing block bno.
 * If bno lies in a hole, point to the next entry.  If bno lies
 * past eof, *eofp will be set, and *prevp will contain the last
 * entry (null if none).  Else, *lastxp will be set to the index
 * of the found entry; *gotp will contain the entry.
 */
STATIC xfs_bmbt_rec_host_t *		/* pointer to found extent entry */
xfs_bmap_search_multi_extents(
	xfs_ifork_t	*ifp,		/* inode fork pointer */
	xfs_fileoff_t	bno,		/* block number searched for */
	int		*eofp,		/* out: end of file found */
	xfs_extnum_t	*lastxp,	/* out: last extent index */
	xfs_bmbt_irec_t	*gotp,		/* out: extent entry found */
	xfs_bmbt_irec_t	*prevp)		/* out: previous extent entry found */
{
	xfs_bmbt_rec_host_t *ep;		/* extent record pointer */
	xfs_extnum_t	lastx;		/* last extent index */
1392

1393 1394 1395 1396 1397 1398 1399 1400 1401
	/*
	 * Initialize the extent entry structure to catch access to
	 * uninitialized br_startblock field.
	 */
	gotp->br_startoff = 0xffa5a5a5a5a5a5a5LL;
	gotp->br_blockcount = 0xa55a5a5a5a5a5a5aLL;
	gotp->br_state = XFS_EXT_INVALID;
	gotp->br_startblock = 0xffffa5a5a5a5a5a5LL;
	prevp->br_startoff = NULLFILEOFF;
1402

1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418
	ep = xfs_iext_bno_to_ext(ifp, bno, &lastx);
	if (lastx > 0) {
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx - 1), prevp);
	}
	if (lastx < (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))) {
		xfs_bmbt_get_all(ep, gotp);
		*eofp = 0;
	} else {
		if (lastx > 0) {
			*gotp = *prevp;
		}
		*eofp = 1;
		ep = NULL;
	}
	*lastxp = lastx;
	return ep;
L
Linus Torvalds 已提交
1419 1420
}

1421
/*
1422 1423 1424 1425 1426
 * Search the extents list for the inode, for the extent containing bno.
 * If bno lies in a hole, point to the next entry.  If bno lies past eof,
 * *eofp will be set, and *prevp will contain the last entry (null if none).
 * Else, *lastxp will be set to the index of the found
 * entry; *gotp will contain the entry.
1427
 */
1428
xfs_bmbt_rec_host_t *                 /* pointer to found extent entry */
1429 1430 1431 1432 1433 1434 1435 1436
xfs_bmap_search_extents(
	xfs_inode_t     *ip,            /* incore inode pointer */
	xfs_fileoff_t   bno,            /* block number searched for */
	int             fork,      	/* data or attr fork */
	int             *eofp,          /* out: end of file found */
	xfs_extnum_t    *lastxp,        /* out: last extent index */
	xfs_bmbt_irec_t *gotp,          /* out: extent entry found */
	xfs_bmbt_irec_t *prevp)         /* out: previous extent entry found */
1437
{
1438 1439
	xfs_ifork_t	*ifp;		/* inode fork pointer */
	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 1447 1448 1449 1450
	if (unlikely(!(gotp->br_startblock) && (*lastxp != NULLEXTNUM) &&
		     !(XFS_IS_REALTIME_INODE(ip) && fork == XFS_DATA_FORK))) {
		xfs_alert_tag(ip->i_mount, XFS_PTAG_FSBLOCK_ZERO,
				"Access to block zero in inode %llu "
				"start_block: %llx start_off: %llx "
1451
				"blkcnt: %llx extent-state: %x lastx: %x",
1452 1453 1454 1455 1456 1457 1458 1459
			(unsigned long long)ip->i_ino,
			(unsigned long long)gotp->br_startblock,
			(unsigned long long)gotp->br_startoff,
			(unsigned long long)gotp->br_blockcount,
			gotp->br_state, *lastxp);
		*lastxp = NULLEXTNUM;
		*eofp = 1;
		return NULL;
1460
	}
1461 1462
	return ep;
}
1463

1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493
/*
 * Returns the file-relative block number of the first unused block(s)
 * in the file with at least "len" logically contiguous blocks free.
 * This is the lowest-address hole if the file has holes, else the first block
 * past the end of file.
 * Return 0 if the file is currently local (in-inode).
 */
int						/* error */
xfs_bmap_first_unused(
	xfs_trans_t	*tp,			/* transaction pointer */
	xfs_inode_t	*ip,			/* incore inode */
	xfs_extlen_t	len,			/* size of hole to find */
	xfs_fileoff_t	*first_unused,		/* unused block */
	int		whichfork)		/* data or attr fork */
{
	int		error;			/* error return value */
	int		idx;			/* extent record index */
	xfs_ifork_t	*ifp;			/* inode fork pointer */
	xfs_fileoff_t	lastaddr;		/* last block number seen */
	xfs_fileoff_t	lowest;			/* lowest useful block */
	xfs_fileoff_t	max;			/* starting useful block */
	xfs_fileoff_t	off;			/* offset for this block */
	xfs_extnum_t	nextents;		/* number of extent entries */

	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE ||
	       XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ||
	       XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL);
	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
		*first_unused = 0;
		return 0;
1494
	}
1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512
	ifp = XFS_IFORK_PTR(ip, whichfork);
	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
	    (error = xfs_iread_extents(tp, ip, whichfork)))
		return error;
	lowest = *first_unused;
	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
	for (idx = 0, lastaddr = 0, max = lowest; idx < nextents; idx++) {
		xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, idx);
		off = xfs_bmbt_get_startoff(ep);
		/*
		 * See if the hole before this extent will work.
		 */
		if (off >= lowest + len && off - max >= len) {
			*first_unused = max;
			return 0;
		}
		lastaddr = off + xfs_bmbt_get_blockcount(ep);
		max = XFS_FILEOFF_MAX(lastaddr, lowest);
1513
	}
1514 1515 1516 1517 1518
	*first_unused = max;
	return 0;
}

/*
1519
 * Returns the file-relative block number of the last block - 1 before
1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542
 * last_block (input value) in the file.
 * This is not based on i_size, it is based on the extent records.
 * Returns 0 for local files, as they do not have extent records.
 */
int						/* error */
xfs_bmap_last_before(
	xfs_trans_t	*tp,			/* transaction pointer */
	xfs_inode_t	*ip,			/* incore inode */
	xfs_fileoff_t	*last_block,		/* last block */
	int		whichfork)		/* data or attr fork */
{
	xfs_fileoff_t	bno;			/* input file offset */
	int		eof;			/* hit end of file */
	xfs_bmbt_rec_host_t *ep;		/* pointer to last extent */
	int		error;			/* error return value */
	xfs_bmbt_irec_t	got;			/* current extent value */
	xfs_ifork_t	*ifp;			/* inode fork pointer */
	xfs_extnum_t	lastx;			/* last extent used */
	xfs_bmbt_irec_t	prev;			/* previous extent value */

	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
D
Dave Chinner 已提交
1543
	       return -EIO;
1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557
	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
		*last_block = 0;
		return 0;
	}
	ifp = XFS_IFORK_PTR(ip, whichfork);
	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
	    (error = xfs_iread_extents(tp, ip, whichfork)))
		return error;
	bno = *last_block - 1;
	ep = xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
		&prev);
	if (eof || xfs_bmbt_get_startoff(ep) > bno) {
		if (prev.br_startoff == NULLFILEOFF)
			*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 1565 1566
	return 0;
}

D
Dave Chinner 已提交
1567
int
1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582
xfs_bmap_last_extent(
	struct xfs_trans	*tp,
	struct xfs_inode	*ip,
	int			whichfork,
	struct xfs_bmbt_irec	*rec,
	int			*is_empty)
{
	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
	int			error;
	int			nextents;

	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
		error = xfs_iread_extents(tp, ip, whichfork);
		if (error)
			return error;
1583 1584
	}

1585 1586 1587 1588 1589
	nextents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
	if (nextents == 0) {
		*is_empty = 1;
		return 0;
	}
1590

1591 1592
	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, nextents - 1), rec);
	*is_empty = 0;
1593 1594 1595
	return 0;
}

1596 1597 1598 1599 1600 1601
/*
 * Check the last inode extent to determine whether this allocation will result
 * in blocks being allocated at the end of the file. When we allocate new data
 * blocks at the end of the file which do not start at the previous data block,
 * we will try to align the new blocks at stripe unit boundaries.
 *
1602
 * Returns 1 in bma->aeof if the file (fork) is empty as any new write will be
1603 1604 1605 1606 1607 1608
 * at, or past the EOF.
 */
STATIC int
xfs_bmap_isaeof(
	struct xfs_bmalloca	*bma,
	int			whichfork)
L
Linus Torvalds 已提交
1609
{
1610 1611 1612
	struct xfs_bmbt_irec	rec;
	int			is_empty;
	int			error;
L
Linus Torvalds 已提交
1613

1614 1615 1616
	bma->aeof = 0;
	error = xfs_bmap_last_extent(NULL, bma->ip, whichfork, &rec,
				     &is_empty);
1617
	if (error)
1618
		return error;
L
Linus Torvalds 已提交
1619

1620 1621 1622 1623 1624
	if (is_empty) {
		bma->aeof = 1;
		return 0;
	}

L
Linus Torvalds 已提交
1625
	/*
1626 1627
	 * Check if we are allocation or past the last extent, or at least into
	 * the last delayed allocated extent.
L
Linus Torvalds 已提交
1628
	 */
1629 1630 1631 1632 1633
	bma->aeof = bma->offset >= rec.br_startoff + rec.br_blockcount ||
		(bma->offset >= rec.br_startoff &&
		 isnullstartblock(rec.br_startblock));
	return 0;
}
L
Linus Torvalds 已提交
1634

1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648
/*
 * Returns the file-relative block number of the first block past eof in
 * the file.  This is not based on i_size, it is based on the extent records.
 * Returns 0 for local files, as they do not have extent records.
 */
int
xfs_bmap_last_offset(
	struct xfs_inode	*ip,
	xfs_fileoff_t		*last_block,
	int			whichfork)
{
	struct xfs_bmbt_irec	rec;
	int			is_empty;
	int			error;
1649

1650
	*last_block = 0;
1651

1652 1653
	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL)
		return 0;
1654

1655 1656
	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE &&
	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
D
Dave Chinner 已提交
1657
	       return -EIO;
1658

1659 1660
	error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, &is_empty);
	if (error || is_empty)
1661
		return error;
1662 1663

	*last_block = rec.br_startoff + rec.br_blockcount;
1664 1665 1666
	return 0;
}

1667 1668 1669 1670 1671 1672 1673 1674 1675
/*
 * Returns whether the selected fork of the inode has exactly one
 * block or not.  For the data fork we check this matches di_size,
 * implying the file's range is 0..bsize-1.
 */
int					/* 1=>1 block, 0=>otherwise */
xfs_bmap_one_block(
	xfs_inode_t	*ip,		/* incore inode */
	int		whichfork)	/* data or attr fork */
C
Christoph Hellwig 已提交
1676
{
1677 1678 1679 1680
	xfs_bmbt_rec_host_t *ep;	/* ptr to fork's extent */
	xfs_ifork_t	*ifp;		/* inode fork pointer */
	int		rval;		/* return value */
	xfs_bmbt_irec_t	s;		/* internal version of extent */
C
Christoph Hellwig 已提交
1681

1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698
#ifndef DEBUG
	if (whichfork == XFS_DATA_FORK)
		return XFS_ISIZE(ip) == ip->i_mount->m_sb.sb_blocksize;
#endif	/* !DEBUG */
	if (XFS_IFORK_NEXTENTS(ip, whichfork) != 1)
		return 0;
	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
		return 0;
	ifp = XFS_IFORK_PTR(ip, whichfork);
	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
	ep = xfs_iext_get_ext(ifp, 0);
	xfs_bmbt_get_all(ep, &s);
	rval = s.br_startoff == 0 && s.br_blockcount == 1;
	if (rval && whichfork == XFS_DATA_FORK)
		ASSERT(XFS_ISIZE(ip) == ip->i_mount->m_sb.sb_blocksize);
	return rval;
}
C
Christoph Hellwig 已提交
1699

1700 1701 1702
/*
 * Extent tree manipulation functions used during allocation.
 */
C
Christoph Hellwig 已提交
1703

1704 1705 1706 1707 1708
/*
 * Convert a delayed allocation to a real allocation.
 */
STATIC int				/* error */
xfs_bmap_add_extent_delay_real(
1709 1710
	struct xfs_bmalloca	*bma,
	int			whichfork)
1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727
{
	struct xfs_bmbt_irec	*new = &bma->got;
	int			diff;	/* temp value */
	xfs_bmbt_rec_host_t	*ep;	/* extent entry for idx */
	int			error;	/* error return value */
	int			i;	/* temp state */
	xfs_ifork_t		*ifp;	/* inode fork pointer */
	xfs_fileoff_t		new_endoff;	/* end offset of new entry */
	xfs_bmbt_irec_t		r[3];	/* neighbor extent entries */
					/* left is 0, right is 1, prev is 2 */
	int			rval=0;	/* return value (logging flags) */
	int			state = 0;/* state bits, accessed thru macros */
	xfs_filblks_t		da_new; /* new count del alloc blocks used */
	xfs_filblks_t		da_old; /* old count del alloc blocks used */
	xfs_filblks_t		temp=0;	/* value for da_new calculations */
	xfs_filblks_t		temp2=0;/* value for da_new calculations */
	int			tmp_rval;	/* partial logging flags */
1728
	struct xfs_mount	*mp;
1729
	xfs_extnum_t		*nextents;
C
Christoph Hellwig 已提交
1730

1731
	mp = bma->ip->i_mount;
1732
	ifp = XFS_IFORK_PTR(bma->ip, whichfork);
1733 1734 1735
	ASSERT(whichfork != XFS_ATTR_FORK);
	nextents = (whichfork == XFS_COW_FORK ? &bma->ip->i_cnextents :
						&bma->ip->i_d.di_nextents);
C
Christoph Hellwig 已提交
1736

1737 1738 1739 1740 1741
	ASSERT(bma->idx >= 0);
	ASSERT(bma->idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
	ASSERT(!isnullstartblock(new->br_startblock));
	ASSERT(!bma->cur ||
	       (bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
C
Christoph Hellwig 已提交
1742

1743
	XFS_STATS_INC(mp, xs_add_exlist);
C
Christoph Hellwig 已提交
1744

1745 1746 1747
#define	LEFT		r[0]
#define	RIGHT		r[1]
#define	PREV		r[2]
C
Christoph Hellwig 已提交
1748

1749 1750 1751
	if (whichfork == XFS_COW_FORK)
		state |= BMAP_COWFORK;

C
Christoph Hellwig 已提交
1752
	/*
1753
	 * Set up a bunch of variables to make the tests simpler.
C
Christoph Hellwig 已提交
1754
	 */
1755 1756 1757 1758 1759 1760 1761 1762 1763
	ep = xfs_iext_get_ext(ifp, bma->idx);
	xfs_bmbt_get_all(ep, &PREV);
	new_endoff = new->br_startoff + new->br_blockcount;
	ASSERT(PREV.br_startoff <= new->br_startoff);
	ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);

	da_old = startblockval(PREV.br_startblock);
	da_new = 0;

C
Christoph Hellwig 已提交
1764
	/*
1765 1766
	 * Set flags determining what part of the previous delayed allocation
	 * extent is being replaced by a real allocation.
C
Christoph Hellwig 已提交
1767
	 */
1768 1769 1770 1771
	if (PREV.br_startoff == new->br_startoff)
		state |= BMAP_LEFT_FILLING;
	if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
		state |= BMAP_RIGHT_FILLING;
C
Christoph Hellwig 已提交
1772 1773

	/*
1774 1775
	 * Check and set flags if this segment has a left neighbor.
	 * Don't set contiguous if the combined extent would be too large.
C
Christoph Hellwig 已提交
1776
	 */
1777 1778 1779
	if (bma->idx > 0) {
		state |= BMAP_LEFT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx - 1), &LEFT);
1780

1781 1782
		if (isnullstartblock(LEFT.br_startblock))
			state |= BMAP_LEFT_DELAY;
1783 1784
	}

1785 1786 1787 1788 1789 1790
	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
	    LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
	    LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
	    LEFT.br_state == new->br_state &&
	    LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
		state |= BMAP_LEFT_CONTIG;
1791

L
Linus Torvalds 已提交
1792
	/*
1793 1794 1795
	 * Check and set flags if this segment has a right neighbor.
	 * Don't set contiguous if the combined extent would be too large.
	 * Also check for all-three-contiguous being too large.
L
Linus Torvalds 已提交
1796
	 */
1797
	if (bma->idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
1798 1799
		state |= BMAP_RIGHT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx + 1), &RIGHT);
1800

1801 1802
		if (isnullstartblock(RIGHT.br_startblock))
			state |= BMAP_RIGHT_DELAY;
L
Linus Torvalds 已提交
1803
	}
1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818

	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
	    new_endoff == RIGHT.br_startoff &&
	    new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
	    new->br_state == RIGHT.br_state &&
	    new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
	    ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
		       BMAP_RIGHT_FILLING)) !=
		      (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
		       BMAP_RIGHT_FILLING) ||
	     LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
			<= MAXEXTLEN))
		state |= BMAP_RIGHT_CONTIG;

	error = 0;
L
Linus Torvalds 已提交
1819
	/*
1820
	 * Switch out based on the FILLING and CONTIG state bits.
L
Linus Torvalds 已提交
1821
	 */
1822 1823 1824 1825
	switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
			 BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
	     BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
L
Linus Torvalds 已提交
1826
		/*
1827 1828
		 * Filling in all of a previously delayed allocation extent.
		 * The left and right neighbors are both contiguous with new.
L
Linus Torvalds 已提交
1829
		 */
1830 1831 1832 1833 1834 1835 1836 1837
		bma->idx--;
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
			LEFT.br_blockcount + PREV.br_blockcount +
			RIGHT.br_blockcount);
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);

		xfs_iext_remove(bma->ip, bma->idx + 1, 2, state);
1838
		(*nextents)--;
1839 1840 1841 1842 1843 1844 1845 1846 1847
		if (bma->cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			error = xfs_bmbt_lookup_eq(bma->cur, RIGHT.br_startoff,
					RIGHT.br_startblock,
					RIGHT.br_blockcount, &i);
			if (error)
				goto done;
1848
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1849 1850 1851
			error = xfs_btree_delete(bma->cur, &i);
			if (error)
				goto done;
1852
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1853 1854 1855
			error = xfs_btree_decrement(bma->cur, 0, &i);
			if (error)
				goto done;
1856
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867
			error = xfs_bmbt_update(bma->cur, LEFT.br_startoff,
					LEFT.br_startblock,
					LEFT.br_blockcount +
					PREV.br_blockcount +
					RIGHT.br_blockcount, LEFT.br_state);
			if (error)
				goto done;
		}
		break;

	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1868
		/*
1869 1870
		 * Filling in all of a previously delayed allocation extent.
		 * The left neighbor is contiguous, the right is not.
1871
		 */
1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888
		bma->idx--;

		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
			LEFT.br_blockcount + PREV.br_blockcount);
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);

		xfs_iext_remove(bma->ip, bma->idx + 1, 1, state);
		if (bma->cur == NULL)
			rval = XFS_ILOG_DEXT;
		else {
			rval = 0;
			error = xfs_bmbt_lookup_eq(bma->cur, LEFT.br_startoff,
					LEFT.br_startblock, LEFT.br_blockcount,
					&i);
			if (error)
				goto done;
1889
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1890 1891 1892 1893 1894 1895 1896 1897 1898 1899
			error = xfs_bmbt_update(bma->cur, LEFT.br_startoff,
					LEFT.br_startblock,
					LEFT.br_blockcount +
					PREV.br_blockcount, LEFT.br_state);
			if (error)
				goto done;
		}
		break;

	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1900
		/*
1901 1902
		 * Filling in all of a previously delayed allocation extent.
		 * The right neighbor is contiguous, the left is not.
1903
		 */
1904 1905 1906 1907 1908
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_startblock(ep, new->br_startblock);
		xfs_bmbt_set_blockcount(ep,
			PREV.br_blockcount + RIGHT.br_blockcount);
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
1909

1910 1911 1912 1913 1914 1915 1916 1917 1918 1919
		xfs_iext_remove(bma->ip, bma->idx + 1, 1, state);
		if (bma->cur == NULL)
			rval = XFS_ILOG_DEXT;
		else {
			rval = 0;
			error = xfs_bmbt_lookup_eq(bma->cur, RIGHT.br_startoff,
					RIGHT.br_startblock,
					RIGHT.br_blockcount, &i);
			if (error)
				goto done;
1920
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1921 1922 1923 1924 1925 1926 1927 1928 1929 1930
			error = xfs_bmbt_update(bma->cur, PREV.br_startoff,
					new->br_startblock,
					PREV.br_blockcount +
					RIGHT.br_blockcount, PREV.br_state);
			if (error)
				goto done;
		}
		break;

	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
1931
		/*
1932 1933 1934
		 * Filling in all of a previously delayed allocation extent.
		 * Neither the left nor right neighbors are contiguous with
		 * the new one.
1935
		 */
1936 1937 1938
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_startblock(ep, new->br_startblock);
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
1939

1940
		(*nextents)++;
1941 1942 1943 1944 1945 1946 1947 1948 1949
		if (bma->cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
					new->br_startblock, new->br_blockcount,
					&i);
			if (error)
				goto done;
1950
			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
1951 1952 1953 1954
			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
			error = xfs_btree_insert(bma->cur, &i);
			if (error)
				goto done;
1955
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1956 1957
		}
		break;
L
Linus Torvalds 已提交
1958

1959
	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
L
Linus Torvalds 已提交
1960
		/*
1961 1962
		 * Filling in the first part of a previous delayed allocation.
		 * The left neighbor is contiguous.
L
Linus Torvalds 已提交
1963
		 */
1964 1965 1966 1967 1968 1969
		trace_xfs_bmap_pre_update(bma->ip, bma->idx - 1, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx - 1),
			LEFT.br_blockcount + new->br_blockcount);
		xfs_bmbt_set_startoff(ep,
			PREV.br_startoff + new->br_blockcount);
		trace_xfs_bmap_post_update(bma->ip, bma->idx - 1, state, _THIS_IP_);
L
Linus Torvalds 已提交
1970

1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982
		temp = PREV.br_blockcount - new->br_blockcount;
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep, temp);
		if (bma->cur == NULL)
			rval = XFS_ILOG_DEXT;
		else {
			rval = 0;
			error = xfs_bmbt_lookup_eq(bma->cur, LEFT.br_startoff,
					LEFT.br_startblock, LEFT.br_blockcount,
					&i);
			if (error)
				goto done;
1983
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
1984 1985 1986 1987 1988
			error = xfs_bmbt_update(bma->cur, LEFT.br_startoff,
					LEFT.br_startblock,
					LEFT.br_blockcount +
					new->br_blockcount,
					LEFT.br_state);
C
Christoph Hellwig 已提交
1989
			if (error)
L
Linus Torvalds 已提交
1990 1991
				goto done;
		}
1992 1993 1994 1995 1996 1997 1998 1999 2000
		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
			startblockval(PREV.br_startblock));
		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);

		bma->idx--;
		break;

	case BMAP_LEFT_FILLING:
L
Linus Torvalds 已提交
2001
		/*
2002 2003
		 * Filling in the first part of a previous delayed allocation.
		 * The left neighbor is not contiguous.
L
Linus Torvalds 已提交
2004
		 */
2005 2006 2007 2008 2009
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_startoff(ep, new_endoff);
		temp = PREV.br_blockcount - new->br_blockcount;
		xfs_bmbt_set_blockcount(ep, temp);
		xfs_iext_insert(bma->ip, bma->idx, 1, new, state);
2010
		(*nextents)++;
2011 2012
		if (bma->cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
L
Linus Torvalds 已提交
2013
		else {
2014 2015 2016 2017 2018 2019
			rval = XFS_ILOG_CORE;
			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
					new->br_startblock, new->br_blockcount,
					&i);
			if (error)
				goto done;
2020
			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2021 2022 2023
			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
			error = xfs_btree_insert(bma->cur, &i);
			if (error)
L
Linus Torvalds 已提交
2024
				goto done;
2025
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
L
Linus Torvalds 已提交
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 2033 2034
			rval |= tmp_rval;
			if (error)
				goto done;
L
Linus Torvalds 已提交
2035
		}
2036 2037 2038 2039 2040 2041
		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
			startblockval(PREV.br_startblock) -
			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
		ep = xfs_iext_get_ext(ifp, bma->idx + 1);
		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
		trace_xfs_bmap_post_update(bma->ip, bma->idx + 1, state, _THIS_IP_);
L
Linus Torvalds 已提交
2042 2043
		break;

2044
	case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
L
Linus Torvalds 已提交
2045
		/*
2046 2047
		 * Filling in the last part of a previous delayed allocation.
		 * The right neighbor is contiguous with the new allocation.
L
Linus Torvalds 已提交
2048
		 */
2049 2050
		temp = PREV.br_blockcount - new->br_blockcount;
		trace_xfs_bmap_pre_update(bma->ip, bma->idx + 1, state, _THIS_IP_);
L
Linus Torvalds 已提交
2051
		xfs_bmbt_set_blockcount(ep, temp);
2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065
		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, bma->idx + 1),
			new->br_startoff, new->br_startblock,
			new->br_blockcount + RIGHT.br_blockcount,
			RIGHT.br_state);
		trace_xfs_bmap_post_update(bma->ip, bma->idx + 1, state, _THIS_IP_);
		if (bma->cur == NULL)
			rval = XFS_ILOG_DEXT;
		else {
			rval = 0;
			error = xfs_bmbt_lookup_eq(bma->cur, RIGHT.br_startoff,
					RIGHT.br_startblock,
					RIGHT.br_blockcount, &i);
			if (error)
				goto done;
2066
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2067 2068 2069 2070 2071 2072 2073
			error = xfs_bmbt_update(bma->cur, new->br_startoff,
					new->br_startblock,
					new->br_blockcount +
					RIGHT.br_blockcount,
					RIGHT.br_state);
			if (error)
				goto done;
L
Linus Torvalds 已提交
2074
		}
2075 2076 2077 2078 2079 2080 2081 2082

		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
			startblockval(PREV.br_startblock));
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);

		bma->idx++;
L
Linus Torvalds 已提交
2083 2084
		break;

2085
	case BMAP_RIGHT_FILLING:
L
Linus Torvalds 已提交
2086
		/*
2087 2088
		 * Filling in the last part of a previous delayed allocation.
		 * The right neighbor is not contiguous.
L
Linus Torvalds 已提交
2089
		 */
2090 2091
		temp = PREV.br_blockcount - new->br_blockcount;
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
L
Linus Torvalds 已提交
2092
		xfs_bmbt_set_blockcount(ep, temp);
2093
		xfs_iext_insert(bma->ip, bma->idx + 1, 1, new, state);
2094
		(*nextents)++;
2095 2096 2097 2098 2099 2100 2101 2102 2103
		if (bma->cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
					new->br_startblock, new->br_blockcount,
					&i);
			if (error)
				goto done;
2104
			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2105 2106 2107 2108
			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
			error = xfs_btree_insert(bma->cur, &i);
			if (error)
				goto done;
2109
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
L
Linus Torvalds 已提交
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 2117 2118
			rval |= tmp_rval;
			if (error)
				goto done;
L
Linus Torvalds 已提交
2119
		}
2120 2121 2122 2123 2124 2125 2126 2127
		da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
			startblockval(PREV.br_startblock) -
			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
		ep = xfs_iext_get_ext(ifp, bma->idx);
		xfs_bmbt_set_startblock(ep, nullstartblock(da_new));
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);

		bma->idx++;
L
Linus Torvalds 已提交
2128 2129 2130 2131
		break;

	case 0:
		/*
2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149
		 * Filling in the middle part of a previous delayed allocation.
		 * Contiguity is impossible here.
		 * This case is avoided almost all the time.
		 *
		 * We start with a delayed allocation:
		 *
		 * +ddddddddddddddddddddddddddddddddddddddddddddddddddddddd+
		 *  PREV @ idx
		 *
	         * and we are allocating:
		 *                     +rrrrrrrrrrrrrrrrr+
		 *			      new
		 *
		 * and we set it up for insertion as:
		 * +ddddddddddddddddddd+rrrrrrrrrrrrrrrrr+ddddddddddddddddd+
		 *                            new
		 *  PREV @ idx          LEFT              RIGHT
		 *                      inserted at idx + 1
L
Linus Torvalds 已提交
2150
		 */
2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162
		temp = new->br_startoff - PREV.br_startoff;
		temp2 = PREV.br_startoff + PREV.br_blockcount - new_endoff;
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, 0, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep, temp);	/* truncate PREV */
		LEFT = *new;
		RIGHT.br_state = PREV.br_state;
		RIGHT.br_startblock = nullstartblock(
				(int)xfs_bmap_worst_indlen(bma->ip, temp2));
		RIGHT.br_startoff = new_endoff;
		RIGHT.br_blockcount = temp2;
		/* insert LEFT (r[0]) and RIGHT (r[1]) at the same time */
		xfs_iext_insert(bma->ip, bma->idx + 1, 2, &LEFT, state);
2163
		(*nextents)++;
2164 2165 2166 2167 2168 2169 2170 2171 2172
		if (bma->cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			error = xfs_bmbt_lookup_eq(bma->cur, new->br_startoff,
					new->br_startblock, new->br_blockcount,
					&i);
			if (error)
				goto done;
2173
			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2174 2175 2176 2177
			bma->cur->bc_rec.b.br_state = XFS_EXT_NORM;
			error = xfs_btree_insert(bma->cur, &i);
			if (error)
				goto done;
2178
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
L
Linus Torvalds 已提交
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 2186 2187 2188 2189 2190 2191 2192 2193
			rval |= tmp_rval;
			if (error)
				goto done;
		}
		temp = xfs_bmap_worst_indlen(bma->ip, temp);
		temp2 = xfs_bmap_worst_indlen(bma->ip, temp2);
		diff = (int)(temp + temp2 - startblockval(PREV.br_startblock) -
			(bma->cur ? bma->cur->bc_private.b.allocated : 0));
		if (diff > 0) {
2194 2195
			error = xfs_mod_fdblocks(bma->ip->i_mount,
						 -((int64_t)diff), false);
2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225
			ASSERT(!error);
			if (error)
				goto done;
		}

		ep = xfs_iext_get_ext(ifp, bma->idx);
		xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
		trace_xfs_bmap_pre_update(bma->ip, bma->idx + 2, state, _THIS_IP_);
		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, bma->idx + 2),
			nullstartblock((int)temp2));
		trace_xfs_bmap_post_update(bma->ip, bma->idx + 2, state, _THIS_IP_);

		bma->idx++;
		da_new = temp + temp2;
		break;

	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
	case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
	case BMAP_LEFT_CONTIG:
	case BMAP_RIGHT_CONTIG:
		/*
		 * These cases are all impossible.
		 */
		ASSERT(0);
	}

2226 2227 2228 2229 2230
	/* add reverse mapping */
	error = xfs_rmap_map_extent(mp, bma->dfops, bma->ip, whichfork, new);
	if (error)
		goto done;

2231
	/* convert to a btree if necessary */
2232
	if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
2233 2234 2235 2236
		int	tmp_logflags;	/* partial log flag return val */

		ASSERT(bma->cur == NULL);
		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 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250
		bma->logflags |= tmp_logflags;
		if (error)
			goto done;
	}

	/* adjust for changes in reserved delayed indirect blocks */
	if (da_old || da_new) {
		temp = da_new;
		if (bma->cur)
			temp += bma->cur->bc_private.b.allocated;
		ASSERT(temp <= da_old);
		if (temp < da_old)
2251 2252
			xfs_mod_fdblocks(bma->ip->i_mount,
					(int64_t)(da_old - temp), false);
2253
	}
2254 2255 2256 2257 2258

	/* clear out the allocated field, done with it now in any case. */
	if (bma->cur)
		bma->cur->bc_private.b.allocated = 0;

2259
	xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
L
Linus Torvalds 已提交
2260
done:
2261 2262
	if (whichfork != XFS_COW_FORK)
		bma->logflags |= rval;
L
Linus Torvalds 已提交
2263
	return error;
2264 2265 2266
#undef	LEFT
#undef	RIGHT
#undef	PREV
L
Linus Torvalds 已提交
2267 2268 2269
}

/*
2270
 * Convert an unwritten allocation to a real allocation or vice versa.
L
Linus Torvalds 已提交
2271
 */
2272 2273 2274 2275 2276 2277 2278 2279
STATIC int				/* error */
xfs_bmap_add_extent_unwritten_real(
	struct xfs_trans	*tp,
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_extnum_t		*idx,	/* extent number to update/insert */
	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
	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 */
L
Linus Torvalds 已提交
2282
{
2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294
	xfs_btree_cur_t		*cur;	/* btree cursor */
	xfs_bmbt_rec_host_t	*ep;	/* extent entry for idx */
	int			error;	/* error return value */
	int			i;	/* temp state */
	xfs_ifork_t		*ifp;	/* inode fork pointer */
	xfs_fileoff_t		new_endoff;	/* end offset of new entry */
	xfs_exntst_t		newext;	/* new extent state */
	xfs_exntst_t		oldext;	/* old extent state */
	xfs_bmbt_irec_t		r[3];	/* neighbor extent entries */
					/* left is 0, right is 1, prev is 2 */
	int			rval=0;	/* return value (logging flags) */
	int			state = 0;/* state bits, accessed thru macros */
2295
	struct xfs_mount	*mp = tp->t_mountp;
L
Linus Torvalds 已提交
2296

2297
	*logflagsp = 0;
L
Linus Torvalds 已提交
2298

2299 2300
	cur = *curp;
	ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
2301

2302 2303 2304 2305
	ASSERT(*idx >= 0);
	ASSERT(*idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
	ASSERT(!isnullstartblock(new->br_startblock));

2306
	XFS_STATS_INC(mp, xs_add_exlist);
2307 2308 2309 2310

#define	LEFT		r[0]
#define	RIGHT		r[1]
#define	PREV		r[2]
2311

L
Linus Torvalds 已提交
2312
	/*
2313
	 * Set up a bunch of variables to make the tests simpler.
L
Linus Torvalds 已提交
2314
	 */
2315 2316 2317 2318 2319 2320 2321 2322 2323 2324
	error = 0;
	ep = xfs_iext_get_ext(ifp, *idx);
	xfs_bmbt_get_all(ep, &PREV);
	newext = new->br_state;
	oldext = (newext == XFS_EXT_UNWRITTEN) ?
		XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
	ASSERT(PREV.br_state == oldext);
	new_endoff = new->br_startoff + new->br_blockcount;
	ASSERT(PREV.br_startoff <= new->br_startoff);
	ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
2325

L
Linus Torvalds 已提交
2326
	/*
2327 2328
	 * Set flags determining what part of the previous oldext allocation
	 * extent is being replaced by a newext allocation.
L
Linus Torvalds 已提交
2329
	 */
2330 2331 2332 2333 2334
	if (PREV.br_startoff == new->br_startoff)
		state |= BMAP_LEFT_FILLING;
	if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
		state |= BMAP_RIGHT_FILLING;

L
Linus Torvalds 已提交
2335
	/*
2336 2337
	 * Check and set flags if this segment has a left neighbor.
	 * Don't set contiguous if the combined extent would be too large.
L
Linus Torvalds 已提交
2338
	 */
2339 2340 2341 2342 2343 2344
	if (*idx > 0) {
		state |= BMAP_LEFT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &LEFT);

		if (isnullstartblock(LEFT.br_startblock))
			state |= BMAP_LEFT_DELAY;
L
Linus Torvalds 已提交
2345
	}
2346 2347 2348 2349 2350 2351 2352 2353

	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
	    LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
	    LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
	    LEFT.br_state == newext &&
	    LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN)
		state |= BMAP_LEFT_CONTIG;

L
Linus Torvalds 已提交
2354
	/*
2355 2356 2357
	 * Check and set flags if this segment has a right neighbor.
	 * Don't set contiguous if the combined extent would be too large.
	 * Also check for all-three-contiguous being too large.
L
Linus Torvalds 已提交
2358
	 */
2359 2360 2361 2362 2363
	if (*idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
		state |= BMAP_RIGHT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx + 1), &RIGHT);
		if (isnullstartblock(RIGHT.br_startblock))
			state |= BMAP_RIGHT_DELAY;
L
Linus Torvalds 已提交
2364
	}
2365

2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377
	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
	    new_endoff == RIGHT.br_startoff &&
	    new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
	    newext == RIGHT.br_state &&
	    new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN &&
	    ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
		       BMAP_RIGHT_FILLING)) !=
		      (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
		       BMAP_RIGHT_FILLING) ||
	     LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
			<= MAXEXTLEN))
		state |= BMAP_RIGHT_CONTIG;
2378

L
Linus Torvalds 已提交
2379
	/*
2380
	 * Switch out based on the FILLING and CONTIG state bits.
L
Linus Torvalds 已提交
2381
	 */
2382 2383 2384 2385 2386 2387 2388 2389 2390
	switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
			 BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
	     BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
		/*
		 * Setting all of a previous oldext extent to newext.
		 * The left and right neighbors are both contiguous with new.
		 */
		--*idx;
C
Christoph Hellwig 已提交
2391

2392 2393 2394 2395 2396
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
			LEFT.br_blockcount + PREV.br_blockcount +
			RIGHT.br_blockcount);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
C
Christoph Hellwig 已提交
2397

2398 2399 2400 2401 2402 2403 2404 2405 2406 2407
		xfs_iext_remove(ip, *idx + 1, 2, state);
		ip->i_d.di_nextents -= 2;
		if (cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
					RIGHT.br_startblock,
					RIGHT.br_blockcount, &i)))
				goto done;
2408
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2409 2410
			if ((error = xfs_btree_delete(cur, &i)))
				goto done;
2411
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2412 2413
			if ((error = xfs_btree_decrement(cur, 0, &i)))
				goto done;
2414
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2415 2416
			if ((error = xfs_btree_delete(cur, &i)))
				goto done;
2417
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2418 2419
			if ((error = xfs_btree_decrement(cur, 0, &i)))
				goto done;
2420
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2421 2422 2423 2424 2425 2426 2427
			if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
				LEFT.br_startblock,
				LEFT.br_blockcount + PREV.br_blockcount +
				RIGHT.br_blockcount, LEFT.br_state)))
				goto done;
		}
		break;
C
Christoph Hellwig 已提交
2428

2429 2430 2431 2432 2433 2434
	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
		/*
		 * Setting all of a previous oldext extent to newext.
		 * The left neighbor is contiguous, the right is not.
		 */
		--*idx;
2435

2436 2437 2438 2439
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
			LEFT.br_blockcount + PREV.br_blockcount);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
L
Linus Torvalds 已提交
2440

2441 2442 2443 2444 2445 2446 2447 2448 2449 2450
		xfs_iext_remove(ip, *idx + 1, 1, state);
		ip->i_d.di_nextents--;
		if (cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
					PREV.br_startblock, PREV.br_blockcount,
					&i)))
				goto done;
2451
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2452 2453
			if ((error = xfs_btree_delete(cur, &i)))
				goto done;
2454
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2455 2456
			if ((error = xfs_btree_decrement(cur, 0, &i)))
				goto done;
2457
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2458 2459 2460 2461 2462 2463 2464
			if ((error = xfs_bmbt_update(cur, LEFT.br_startoff,
				LEFT.br_startblock,
				LEFT.br_blockcount + PREV.br_blockcount,
				LEFT.br_state)))
				goto done;
		}
		break;
L
Linus Torvalds 已提交
2465

2466
	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
L
Linus Torvalds 已提交
2467
		/*
2468 2469
		 * Setting all of a previous oldext extent to newext.
		 * The right neighbor is contiguous, the left is not.
L
Linus Torvalds 已提交
2470
		 */
2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep,
			PREV.br_blockcount + RIGHT.br_blockcount);
		xfs_bmbt_set_state(ep, newext);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
		xfs_iext_remove(ip, *idx + 1, 1, state);
		ip->i_d.di_nextents--;
		if (cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			if ((error = xfs_bmbt_lookup_eq(cur, RIGHT.br_startoff,
					RIGHT.br_startblock,
					RIGHT.br_blockcount, &i)))
				goto done;
2486
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2487 2488
			if ((error = xfs_btree_delete(cur, &i)))
				goto done;
2489
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2490 2491
			if ((error = xfs_btree_decrement(cur, 0, &i)))
				goto done;
2492
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2493 2494 2495 2496 2497
			if ((error = xfs_bmbt_update(cur, new->br_startoff,
				new->br_startblock,
				new->br_blockcount + RIGHT.br_blockcount,
				newext)))
				goto done;
L
Linus Torvalds 已提交
2498
		}
2499
		break;
2500

2501 2502 2503 2504 2505 2506 2507 2508 2509
	case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
		/*
		 * Setting all of a previous oldext extent to newext.
		 * Neither the left nor right neighbors are contiguous with
		 * the new one.
		 */
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_state(ep, newext);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2510

2511 2512 2513 2514 2515 2516 2517 2518
		if (cur == NULL)
			rval = XFS_ILOG_DEXT;
		else {
			rval = 0;
			if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
					new->br_startblock, new->br_blockcount,
					&i)))
				goto done;
2519
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2520 2521 2522 2523 2524 2525
			if ((error = xfs_bmbt_update(cur, new->br_startoff,
				new->br_startblock, new->br_blockcount,
				newext)))
				goto done;
		}
		break;
2526

2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537
	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
		/*
		 * Setting the first part of a previous oldext extent to newext.
		 * The left neighbor is contiguous.
		 */
		trace_xfs_bmap_pre_update(ip, *idx - 1, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx - 1),
			LEFT.br_blockcount + new->br_blockcount);
		xfs_bmbt_set_startoff(ep,
			PREV.br_startoff + new->br_blockcount);
		trace_xfs_bmap_post_update(ip, *idx - 1, state, _THIS_IP_);
L
Linus Torvalds 已提交
2538

2539 2540 2541 2542 2543 2544
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_startblock(ep,
			new->br_startblock + new->br_blockcount);
		xfs_bmbt_set_blockcount(ep,
			PREV.br_blockcount - new->br_blockcount);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2545

2546
		--*idx;
2547

2548 2549 2550 2551 2552 2553 2554 2555
		if (cur == NULL)
			rval = XFS_ILOG_DEXT;
		else {
			rval = 0;
			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
					PREV.br_startblock, PREV.br_blockcount,
					&i)))
				goto done;
2556
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570
			if ((error = xfs_bmbt_update(cur,
				PREV.br_startoff + new->br_blockcount,
				PREV.br_startblock + new->br_blockcount,
				PREV.br_blockcount - new->br_blockcount,
				oldext)))
				goto done;
			if ((error = xfs_btree_decrement(cur, 0, &i)))
				goto done;
			error = xfs_bmbt_update(cur, LEFT.br_startoff,
				LEFT.br_startblock,
				LEFT.br_blockcount + new->br_blockcount,
				LEFT.br_state);
			if (error)
				goto done;
2571
		}
2572
		break;
2573

2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586
	case BMAP_LEFT_FILLING:
		/*
		 * Setting the first part of a previous oldext extent to newext.
		 * The left neighbor is not contiguous.
		 */
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		ASSERT(ep && xfs_bmbt_get_state(ep) == oldext);
		xfs_bmbt_set_startoff(ep, new_endoff);
		xfs_bmbt_set_blockcount(ep,
			PREV.br_blockcount - new->br_blockcount);
		xfs_bmbt_set_startblock(ep,
			new->br_startblock + new->br_blockcount);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
L
Linus Torvalds 已提交
2587

2588 2589 2590 2591 2592 2593 2594 2595 2596 2597
		xfs_iext_insert(ip, *idx, 1, new, state);
		ip->i_d.di_nextents++;
		if (cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
					PREV.br_startblock, PREV.br_blockcount,
					&i)))
				goto done;
2598
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2599 2600 2601 2602 2603 2604 2605 2606 2607
			if ((error = xfs_bmbt_update(cur,
				PREV.br_startoff + new->br_blockcount,
				PREV.br_startblock + new->br_blockcount,
				PREV.br_blockcount - new->br_blockcount,
				oldext)))
				goto done;
			cur->bc_rec.b = *new;
			if ((error = xfs_btree_insert(cur, &i)))
				goto done;
2608
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2609 2610
		}
		break;
L
Linus Torvalds 已提交
2611

2612 2613 2614 2615 2616 2617 2618 2619 2620
	case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
		/*
		 * Setting the last part of a previous oldext extent to newext.
		 * The right neighbor is contiguous with the new allocation.
		 */
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep,
			PREV.br_blockcount - new->br_blockcount);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2621

2622
		++*idx;
L
Linus Torvalds 已提交
2623

2624 2625 2626 2627 2628
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
			new->br_startoff, new->br_startblock,
			new->br_blockcount + RIGHT.br_blockcount, newext);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
L
Linus Torvalds 已提交
2629

2630 2631 2632 2633 2634 2635 2636 2637
		if (cur == NULL)
			rval = XFS_ILOG_DEXT;
		else {
			rval = 0;
			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
					PREV.br_startblock,
					PREV.br_blockcount, &i)))
				goto done;
2638
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652
			if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
				PREV.br_startblock,
				PREV.br_blockcount - new->br_blockcount,
				oldext)))
				goto done;
			if ((error = xfs_btree_increment(cur, 0, &i)))
				goto done;
			if ((error = xfs_bmbt_update(cur, new->br_startoff,
				new->br_startblock,
				new->br_blockcount + RIGHT.br_blockcount,
				newext)))
				goto done;
		}
		break;
L
Linus Torvalds 已提交
2653

2654 2655 2656 2657 2658 2659 2660 2661 2662
	case BMAP_RIGHT_FILLING:
		/*
		 * Setting the last part of a previous oldext extent to newext.
		 * The right neighbor is not contiguous.
		 */
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep,
			PREV.br_blockcount - new->br_blockcount);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
L
Linus Torvalds 已提交
2663

2664 2665
		++*idx;
		xfs_iext_insert(ip, *idx, 1, new, state);
2666

2667 2668 2669 2670 2671 2672 2673 2674 2675
		ip->i_d.di_nextents++;
		if (cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
					PREV.br_startblock, PREV.br_blockcount,
					&i)))
				goto done;
2676
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2677 2678 2679 2680 2681 2682 2683 2684 2685
			if ((error = xfs_bmbt_update(cur, PREV.br_startoff,
				PREV.br_startblock,
				PREV.br_blockcount - new->br_blockcount,
				oldext)))
				goto done;
			if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
					new->br_startblock, new->br_blockcount,
					&i)))
				goto done;
2686
			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2687 2688 2689
			cur->bc_rec.b.br_state = XFS_EXT_NORM;
			if ((error = xfs_btree_insert(cur, &i)))
				goto done;
2690
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2691 2692 2693 2694
		}
		break;

	case 0:
L
Linus Torvalds 已提交
2695
		/*
2696 2697 2698
		 * Setting the middle part of a previous oldext extent to
		 * newext.  Contiguity is impossible here.
		 * One extent becomes three extents.
L
Linus Torvalds 已提交
2699
		 */
2700 2701 2702 2703
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep,
			new->br_startoff - PREV.br_startoff);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
2704

2705 2706 2707 2708 2709 2710
		r[0] = *new;
		r[1].br_startoff = new_endoff;
		r[1].br_blockcount =
			PREV.br_startoff + PREV.br_blockcount - new_endoff;
		r[1].br_startblock = new->br_startblock + new->br_blockcount;
		r[1].br_state = oldext;
2711

2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723
		++*idx;
		xfs_iext_insert(ip, *idx, 2, &r[0], state);

		ip->i_d.di_nextents += 2;
		if (cur == NULL)
			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
		else {
			rval = XFS_ILOG_CORE;
			if ((error = xfs_bmbt_lookup_eq(cur, PREV.br_startoff,
					PREV.br_startblock, PREV.br_blockcount,
					&i)))
				goto done;
2724
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735
			/* new right extent - oldext */
			if ((error = xfs_bmbt_update(cur, r[1].br_startoff,
				r[1].br_startblock, r[1].br_blockcount,
				r[1].br_state)))
				goto done;
			/* new left extent - oldext */
			cur->bc_rec.b = PREV;
			cur->bc_rec.b.br_blockcount =
				new->br_startoff - PREV.br_startoff;
			if ((error = xfs_btree_insert(cur, &i)))
				goto done;
2736
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2737 2738 2739 2740 2741 2742 2743 2744 2745
			/*
			 * Reset the cursor to the position of the new extent
			 * we are about to insert as we can't trust it after
			 * the previous insert.
			 */
			if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
					new->br_startblock, new->br_blockcount,
					&i)))
				goto done;
2746
			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
2747 2748 2749 2750
			/* new middle extent - newext */
			cur->bc_rec.b.br_state = new->br_state;
			if ((error = xfs_btree_insert(cur, &i)))
				goto done;
2751
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
2752
		}
L
Linus Torvalds 已提交
2753
		break;
2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764

	case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
	case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
	case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
	case BMAP_LEFT_CONTIG:
	case BMAP_RIGHT_CONTIG:
		/*
		 * These cases are all impossible.
		 */
L
Linus Torvalds 已提交
2765 2766
		ASSERT(0);
	}
2767

2768 2769 2770 2771 2772
	/* update reverse mappings */
	error = xfs_rmap_convert_extent(mp, dfops, ip, XFS_DATA_FORK, new);
	if (error)
		goto done;

2773 2774 2775 2776 2777
	/* convert to a btree if necessary */
	if (xfs_bmap_needs_btree(ip, XFS_DATA_FORK)) {
		int	tmp_logflags;	/* partial log flag return val */

		ASSERT(cur == NULL);
2778
		error = xfs_bmap_extents_to_btree(tp, ip, first, dfops, &cur,
2779 2780 2781 2782
				0, &tmp_logflags, XFS_DATA_FORK);
		*logflagsp |= tmp_logflags;
		if (error)
			goto done;
L
Linus Torvalds 已提交
2783
	}
2784

2785 2786 2787 2788
	/* clear out the allocated field, done with it now in any case. */
	if (cur) {
		cur->bc_private.b.allocated = 0;
		*curp = cur;
L
Linus Torvalds 已提交
2789
	}
2790

2791 2792 2793
	xfs_bmap_check_leaf_extents(*curp, ip, XFS_DATA_FORK);
done:
	*logflagsp |= rval;
L
Linus Torvalds 已提交
2794
	return error;
2795 2796 2797
#undef	LEFT
#undef	RIGHT
#undef	PREV
L
Linus Torvalds 已提交
2798 2799 2800
}

/*
2801
 * Convert a hole to a delayed allocation.
L
Linus Torvalds 已提交
2802
 */
2803 2804 2805
STATIC void
xfs_bmap_add_extent_hole_delay(
	xfs_inode_t		*ip,	/* incore inode pointer */
2806
	int			whichfork,
2807 2808
	xfs_extnum_t		*idx,	/* extent number to update/insert */
	xfs_bmbt_irec_t		*new)	/* new data to add to file extents */
L
Linus Torvalds 已提交
2809
{
2810 2811 2812 2813 2814 2815 2816
	xfs_ifork_t		*ifp;	/* inode fork pointer */
	xfs_bmbt_irec_t		left;	/* left neighbor extent entry */
	xfs_filblks_t		newlen=0;	/* new indirect size */
	xfs_filblks_t		oldlen=0;	/* old indirect size */
	xfs_bmbt_irec_t		right;	/* right neighbor extent entry */
	int			state;  /* state bits, accessed thru macros */
	xfs_filblks_t		temp=0;	/* temp for indirect calculations */
L
Linus Torvalds 已提交
2817

2818
	ifp = XFS_IFORK_PTR(ip, whichfork);
2819
	state = 0;
2820 2821
	if (whichfork == XFS_COW_FORK)
		state |= BMAP_COWFORK;
2822
	ASSERT(isnullstartblock(new->br_startblock));
L
Linus Torvalds 已提交
2823 2824

	/*
2825
	 * Check and set flags if this segment has a left neighbor
L
Linus Torvalds 已提交
2826
	 */
2827 2828 2829 2830 2831 2832
	if (*idx > 0) {
		state |= BMAP_LEFT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &left);

		if (isnullstartblock(left.br_startblock))
			state |= BMAP_LEFT_DELAY;
L
Linus Torvalds 已提交
2833 2834
	}

2835 2836 2837 2838
	/*
	 * Check and set flags if the current (right) segment exists.
	 * If it doesn't exist, we're converting the hole at end-of-file.
	 */
2839
	if (*idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
2840 2841
		state |= BMAP_RIGHT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx), &right);
L
Linus Torvalds 已提交
2842

2843 2844
		if (isnullstartblock(right.br_startblock))
			state |= BMAP_RIGHT_DELAY;
L
Linus Torvalds 已提交
2845
	}
2846

L
Linus Torvalds 已提交
2847
	/*
2848 2849
	 * Set contiguity flags on the left and right neighbors.
	 * Don't let extents get too large, even if the pieces are contiguous.
L
Linus Torvalds 已提交
2850
	 */
2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862
	if ((state & BMAP_LEFT_VALID) && (state & BMAP_LEFT_DELAY) &&
	    left.br_startoff + left.br_blockcount == new->br_startoff &&
	    left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
		state |= BMAP_LEFT_CONTIG;

	if ((state & BMAP_RIGHT_VALID) && (state & BMAP_RIGHT_DELAY) &&
	    new->br_startoff + new->br_blockcount == right.br_startoff &&
	    new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
	    (!(state & BMAP_LEFT_CONTIG) ||
	     (left.br_blockcount + new->br_blockcount +
	      right.br_blockcount <= MAXEXTLEN)))
		state |= BMAP_RIGHT_CONTIG;
2863 2864

	/*
2865
	 * Switch out based on the contiguity flags.
2866
	 */
2867 2868 2869 2870 2871 2872 2873 2874 2875 2876
	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
		/*
		 * New allocation is contiguous with delayed allocations
		 * on the left and on the right.
		 * Merge all three into a single extent record.
		 */
		--*idx;
		temp = left.br_blockcount + new->br_blockcount +
			right.br_blockcount;
2877

2878 2879 2880 2881 2882 2883 2884 2885 2886
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx), temp);
		oldlen = startblockval(left.br_startblock) +
			startblockval(new->br_startblock) +
			startblockval(right.br_startblock);
		newlen = xfs_bmap_worst_indlen(ip, temp);
		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, *idx),
			nullstartblock((int)newlen));
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
L
Linus Torvalds 已提交
2887

2888 2889
		xfs_iext_remove(ip, *idx + 1, 1, state);
		break;
L
Linus Torvalds 已提交
2890

2891 2892 2893 2894 2895 2896 2897 2898
	case BMAP_LEFT_CONTIG:
		/*
		 * New allocation is contiguous with a delayed allocation
		 * on the left.
		 * Merge the new allocation with the left neighbor.
		 */
		--*idx;
		temp = left.br_blockcount + new->br_blockcount;
L
Linus Torvalds 已提交
2899

2900 2901 2902 2903 2904 2905 2906 2907 2908
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx), temp);
		oldlen = startblockval(left.br_startblock) +
			startblockval(new->br_startblock);
		newlen = xfs_bmap_worst_indlen(ip, temp);
		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, *idx),
			nullstartblock((int)newlen));
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
		break;
L
Linus Torvalds 已提交
2909

2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935
	case BMAP_RIGHT_CONTIG:
		/*
		 * New allocation is contiguous with a delayed allocation
		 * on the right.
		 * Merge the new allocation with the right neighbor.
		 */
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		temp = new->br_blockcount + right.br_blockcount;
		oldlen = startblockval(new->br_startblock) +
			startblockval(right.br_startblock);
		newlen = xfs_bmap_worst_indlen(ip, temp);
		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
			new->br_startoff,
			nullstartblock((int)newlen), temp, right.br_state);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
		break;

	case 0:
		/*
		 * New allocation is not contiguous with another
		 * delayed allocation.
		 * Insert a new entry.
		 */
		oldlen = newlen = 0;
		xfs_iext_insert(ip, *idx, 1, new, state);
		break;
L
Linus Torvalds 已提交
2936
	}
2937 2938
	if (oldlen != newlen) {
		ASSERT(oldlen > newlen);
2939 2940
		xfs_mod_fdblocks(ip->i_mount, (int64_t)(oldlen - newlen),
				 false);
L
Linus Torvalds 已提交
2941
		/*
2942
		 * Nothing to do for disk quota accounting here.
L
Linus Torvalds 已提交
2943 2944 2945 2946 2947
		 */
	}
}

/*
2948
 * Convert a hole to a real allocation.
L
Linus Torvalds 已提交
2949
 */
2950 2951 2952 2953
STATIC int				/* error */
xfs_bmap_add_extent_hole_real(
	struct xfs_bmalloca	*bma,
	int			whichfork)
2954
{
2955 2956 2957 2958 2959 2960 2961 2962
	struct xfs_bmbt_irec	*new = &bma->got;
	int			error;	/* error return value */
	int			i;	/* temp state */
	xfs_ifork_t		*ifp;	/* inode fork pointer */
	xfs_bmbt_irec_t		left;	/* left neighbor extent entry */
	xfs_bmbt_irec_t		right;	/* right neighbor extent entry */
	int			rval=0;	/* return value (logging flags) */
	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 2969 2970 2971 2972
	ASSERT(bma->idx >= 0);
	ASSERT(bma->idx <= ifp->if_bytes / sizeof(struct xfs_bmbt_rec));
	ASSERT(!isnullstartblock(new->br_startblock));
	ASSERT(!bma->cur ||
	       !(bma->cur->bc_private.b.flags & XFS_BTCUR_BPRV_WASDEL));
D
Darrick J. Wong 已提交
2973
	ASSERT(whichfork != XFS_COW_FORK);
2974

2975
	XFS_STATS_INC(mp, xs_add_exlist);
2976

2977 2978 2979
	state = 0;
	if (whichfork == XFS_ATTR_FORK)
		state |= BMAP_ATTRFORK;
2980

2981 2982 2983 2984 2985 2986 2987 2988 2989
	/*
	 * Check and set flags if this segment has a left neighbor.
	 */
	if (bma->idx > 0) {
		state |= BMAP_LEFT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx - 1), &left);
		if (isnullstartblock(left.br_startblock))
			state |= BMAP_LEFT_DELAY;
	}
2990 2991

	/*
2992 2993
	 * Check and set flags if this segment has a current value.
	 * Not true if we're inserting into the "hole" at eof.
2994
	 */
2995 2996 2997 2998 2999 3000
	if (bma->idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
		state |= BMAP_RIGHT_VALID;
		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx), &right);
		if (isnullstartblock(right.br_startblock))
			state |= BMAP_RIGHT_DELAY;
	}
3001

3002 3003 3004 3005 3006 3007 3008 3009 3010 3011
	/*
	 * We're inserting a real allocation between "left" and "right".
	 * Set the contiguity flags.  Don't let extents get too large.
	 */
	if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
	    left.br_startoff + left.br_blockcount == new->br_startoff &&
	    left.br_startblock + left.br_blockcount == new->br_startblock &&
	    left.br_state == new->br_state &&
	    left.br_blockcount + new->br_blockcount <= MAXEXTLEN)
		state |= BMAP_LEFT_CONTIG;
3012

3013 3014 3015 3016 3017 3018 3019 3020 3021
	if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
	    new->br_startoff + new->br_blockcount == right.br_startoff &&
	    new->br_startblock + new->br_blockcount == right.br_startblock &&
	    new->br_state == right.br_state &&
	    new->br_blockcount + right.br_blockcount <= MAXEXTLEN &&
	    (!(state & BMAP_LEFT_CONTIG) ||
	     left.br_blockcount + new->br_blockcount +
	     right.br_blockcount <= MAXEXTLEN))
		state |= BMAP_RIGHT_CONTIG;
3022

3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039
	error = 0;
	/*
	 * Select which case we're in here, and implement it.
	 */
	switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
	case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
		/*
		 * New allocation is contiguous with real allocations on the
		 * left and on the right.
		 * Merge all three into a single extent record.
		 */
		--bma->idx;
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
			left.br_blockcount + new->br_blockcount +
			right.br_blockcount);
		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 3044 3045 3046 3047 3048 3049 3050 3051 3052 3053
		XFS_IFORK_NEXT_SET(bma->ip, whichfork,
			XFS_IFORK_NEXTENTS(bma->ip, whichfork) - 1);
		if (bma->cur == NULL) {
			rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
		} else {
			rval = XFS_ILOG_CORE;
			error = xfs_bmbt_lookup_eq(bma->cur, right.br_startoff,
					right.br_startblock, right.br_blockcount,
					&i);
			if (error)
				goto done;
3054
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3055 3056 3057
			error = xfs_btree_delete(bma->cur, &i);
			if (error)
				goto done;
3058
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3059 3060 3061
			error = xfs_btree_decrement(bma->cur, 0, &i);
			if (error)
				goto done;
3062
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3063 3064 3065 3066 3067 3068 3069 3070 3071 3072
			error = xfs_bmbt_update(bma->cur, left.br_startoff,
					left.br_startblock,
					left.br_blockcount +
						new->br_blockcount +
						right.br_blockcount,
					left.br_state);
			if (error)
				goto done;
		}
		break;
3073

3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084
	case BMAP_LEFT_CONTIG:
		/*
		 * New allocation is contiguous with a real allocation
		 * on the left.
		 * Merge the new allocation with the left neighbor.
		 */
		--bma->idx;
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, bma->idx),
			left.br_blockcount + new->br_blockcount);
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
L
Linus Torvalds 已提交
3085

3086 3087 3088 3089 3090 3091 3092 3093 3094
		if (bma->cur == NULL) {
			rval = xfs_ilog_fext(whichfork);
		} else {
			rval = 0;
			error = xfs_bmbt_lookup_eq(bma->cur, left.br_startoff,
					left.br_startblock, left.br_blockcount,
					&i);
			if (error)
				goto done;
3095
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3096 3097 3098 3099 3100 3101 3102 3103 3104
			error = xfs_bmbt_update(bma->cur, left.br_startoff,
					left.br_startblock,
					left.br_blockcount +
						new->br_blockcount,
					left.br_state);
			if (error)
				goto done;
		}
		break;
3105

3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117
	case BMAP_RIGHT_CONTIG:
		/*
		 * New allocation is contiguous with a real allocation
		 * on the right.
		 * Merge the new allocation with the right neighbor.
		 */
		trace_xfs_bmap_pre_update(bma->ip, bma->idx, state, _THIS_IP_);
		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, bma->idx),
			new->br_startoff, new->br_startblock,
			new->br_blockcount + right.br_blockcount,
			right.br_state);
		trace_xfs_bmap_post_update(bma->ip, bma->idx, state, _THIS_IP_);
3118

3119 3120 3121 3122 3123 3124 3125 3126 3127 3128
		if (bma->cur == NULL) {
			rval = xfs_ilog_fext(whichfork);
		} else {
			rval = 0;
			error = xfs_bmbt_lookup_eq(bma->cur,
					right.br_startoff,
					right.br_startblock,
					right.br_blockcount, &i);
			if (error)
				goto done;
3129
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158
			error = xfs_bmbt_update(bma->cur, new->br_startoff,
					new->br_startblock,
					new->br_blockcount +
						right.br_blockcount,
					right.br_state);
			if (error)
				goto done;
		}
		break;

	case 0:
		/*
		 * New allocation is not contiguous with another
		 * real allocation.
		 * Insert a new entry.
		 */
		xfs_iext_insert(bma->ip, bma->idx, 1, new, state);
		XFS_IFORK_NEXT_SET(bma->ip, whichfork,
			XFS_IFORK_NEXTENTS(bma->ip, whichfork) + 1);
		if (bma->cur == NULL) {
			rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
		} else {
			rval = XFS_ILOG_CORE;
			error = xfs_bmbt_lookup_eq(bma->cur,
					new->br_startoff,
					new->br_startblock,
					new->br_blockcount, &i);
			if (error)
				goto done;
3159
			XFS_WANT_CORRUPTED_GOTO(mp, i == 0, done);
3160 3161 3162 3163
			bma->cur->bc_rec.b.br_state = new->br_state;
			error = xfs_btree_insert(bma->cur, &i);
			if (error)
				goto done;
3164
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
3165 3166 3167 3168
		}
		break;
	}

3169 3170 3171 3172 3173
	/* add reverse mapping */
	error = xfs_rmap_map_extent(mp, bma->dfops, bma->ip, whichfork, new);
	if (error)
		goto done;

3174 3175 3176 3177 3178 3179
	/* convert to a btree if necessary */
	if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
		int	tmp_logflags;	/* partial log flag return val */

		ASSERT(bma->cur == NULL);
		error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
3180
				bma->firstblock, bma->dfops, &bma->cur,
3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194
				0, &tmp_logflags, whichfork);
		bma->logflags |= tmp_logflags;
		if (error)
			goto done;
	}

	/* clear out the allocated field, done with it now in any case. */
	if (bma->cur)
		bma->cur->bc_private.b.allocated = 0;

	xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
done:
	bma->logflags |= rval;
	return error;
L
Linus Torvalds 已提交
3195 3196 3197
}

/*
3198
 * Functions used in the extent read, allocate and remove paths
L
Linus Torvalds 已提交
3199 3200
 */

3201 3202 3203
/*
 * Adjust the size of the new extent based on di_extsize and rt extsize.
 */
D
Dave Chinner 已提交
3204
int
3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215
xfs_bmap_extsize_align(
	xfs_mount_t	*mp,
	xfs_bmbt_irec_t	*gotp,		/* next extent pointer */
	xfs_bmbt_irec_t	*prevp,		/* previous extent pointer */
	xfs_extlen_t	extsz,		/* align to this extent size */
	int		rt,		/* is this a realtime inode? */
	int		eof,		/* is extent at end-of-file? */
	int		delay,		/* creating delalloc extent? */
	int		convert,	/* overwriting unwritten extent? */
	xfs_fileoff_t	*offp,		/* in/out: aligned offset */
	xfs_extlen_t	*lenp)		/* in/out: aligned length */
3216
{
3217 3218 3219 3220 3221 3222 3223 3224
	xfs_fileoff_t	orig_off;	/* original offset */
	xfs_extlen_t	orig_alen;	/* original length */
	xfs_fileoff_t	orig_end;	/* original off+len */
	xfs_fileoff_t	nexto;		/* next file offset */
	xfs_fileoff_t	prevo;		/* previous file offset */
	xfs_fileoff_t	align_off;	/* temp for offset */
	xfs_extlen_t	align_alen;	/* temp for length */
	xfs_extlen_t	temp;		/* temp for calculations */
3225

3226
	if (convert)
3227 3228
		return 0;

3229 3230 3231
	orig_off = align_off = *offp;
	orig_alen = align_alen = *lenp;
	orig_end = orig_off + orig_alen;
L
Linus Torvalds 已提交
3232 3233

	/*
3234 3235
	 * If this request overlaps an existing extent, then don't
	 * attempt to perform any additional alignment.
L
Linus Torvalds 已提交
3236
	 */
3237 3238 3239 3240 3241 3242
	if (!delay && !eof &&
	    (orig_off >= gotp->br_startoff) &&
	    (orig_end <= gotp->br_startoff + gotp->br_blockcount)) {
		return 0;
	}

L
Linus Torvalds 已提交
3243
	/*
3244 3245 3246 3247 3248
	 * If the file offset is unaligned vs. the extent size
	 * we need to align it.  This will be possible unless
	 * the file was previously written with a kernel that didn't
	 * perform this alignment, or if a truncate shot us in the
	 * foot.
L
Linus Torvalds 已提交
3249
	 */
3250 3251 3252 3253
	temp = do_mod(orig_off, extsz);
	if (temp) {
		align_alen += temp;
		align_off -= temp;
L
Linus Torvalds 已提交
3254
	}
3255 3256 3257 3258 3259 3260

	/* Same adjustment for the end of the requested area. */
	temp = (align_alen % extsz);
	if (temp)
		align_alen += extsz - temp;

L
Linus Torvalds 已提交
3261
	/*
3262 3263 3264 3265 3266 3267
	 * For large extent hint sizes, the aligned extent might be larger than
	 * MAXEXTLEN. In that case, reduce the size by an extsz so that it pulls
	 * the length back under MAXEXTLEN. The outer allocation loops handle
	 * short allocation just fine, so it is safe to do this. We only want to
	 * do it when we are forced to, though, because it means more allocation
	 * operations are required.
L
Linus Torvalds 已提交
3268
	 */
3269 3270 3271 3272
	while (align_alen > MAXEXTLEN)
		align_alen -= extsz;
	ASSERT(align_alen <= MAXEXTLEN);

L
Linus Torvalds 已提交
3273
	/*
3274 3275
	 * If the previous block overlaps with this proposed allocation
	 * then move the start forward without adjusting the length.
L
Linus Torvalds 已提交
3276
	 */
3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319
	if (prevp->br_startoff != NULLFILEOFF) {
		if (prevp->br_startblock == HOLESTARTBLOCK)
			prevo = prevp->br_startoff;
		else
			prevo = prevp->br_startoff + prevp->br_blockcount;
	} else
		prevo = 0;
	if (align_off != orig_off && align_off < prevo)
		align_off = prevo;
	/*
	 * If the next block overlaps with this proposed allocation
	 * then move the start back without adjusting the length,
	 * but not before offset 0.
	 * This may of course make the start overlap previous block,
	 * and if we hit the offset 0 limit then the next block
	 * can still overlap too.
	 */
	if (!eof && gotp->br_startoff != NULLFILEOFF) {
		if ((delay && gotp->br_startblock == HOLESTARTBLOCK) ||
		    (!delay && gotp->br_startblock == DELAYSTARTBLOCK))
			nexto = gotp->br_startoff + gotp->br_blockcount;
		else
			nexto = gotp->br_startoff;
	} else
		nexto = NULLFILEOFF;
	if (!eof &&
	    align_off + align_alen != orig_end &&
	    align_off + align_alen > nexto)
		align_off = nexto > align_alen ? nexto - align_alen : 0;
	/*
	 * If we're now overlapping the next or previous extent that
	 * means we can't fit an extsz piece in this hole.  Just move
	 * the start forward to the first valid spot and set
	 * the length so we hit the end.
	 */
	if (align_off != orig_off && align_off < prevo)
		align_off = prevo;
	if (align_off + align_alen != orig_end &&
	    align_off + align_alen > nexto &&
	    nexto != NULLFILEOFF) {
		ASSERT(nexto > prevo);
		align_alen = nexto - align_off;
	}
L
Linus Torvalds 已提交
3320

3321 3322 3323 3324 3325
	/*
	 * If realtime, and the result isn't a multiple of the realtime
	 * extent size we need to remove blocks until it is.
	 */
	if (rt && (temp = (align_alen % mp->m_sb.sb_rextsize))) {
L
Linus Torvalds 已提交
3326
		/*
3327 3328
		 * We're not covering the original request, or
		 * we won't be able to once we fix the length.
L
Linus Torvalds 已提交
3329
		 */
3330 3331 3332
		if (orig_off < align_off ||
		    orig_end > align_off + align_alen ||
		    align_alen - temp < orig_alen)
D
Dave Chinner 已提交
3333
			return -EINVAL;
L
Linus Torvalds 已提交
3334
		/*
3335
		 * Try to fix it by moving the start up.
L
Linus Torvalds 已提交
3336
		 */
3337 3338 3339
		if (align_off + temp <= orig_off) {
			align_alen -= temp;
			align_off += temp;
L
Linus Torvalds 已提交
3340
		}
3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352
		/*
		 * Try to fix it by moving the end in.
		 */
		else if (align_off + align_alen - temp >= orig_end)
			align_alen -= temp;
		/*
		 * Set the start to the minimum then trim the length.
		 */
		else {
			align_alen -= orig_off - align_off;
			align_off = orig_off;
			align_alen -= align_alen % mp->m_sb.sb_rextsize;
L
Linus Torvalds 已提交
3353 3354
		}
		/*
3355
		 * Result doesn't cover the request, fail it.
L
Linus Torvalds 已提交
3356
		 */
3357
		if (orig_off < align_off || orig_end > align_off + align_alen)
D
Dave Chinner 已提交
3358
			return -EINVAL;
3359 3360
	} else {
		ASSERT(orig_off >= align_off);
3361 3362 3363
		/* see MAXEXTLEN handling above */
		ASSERT(orig_end <= align_off + align_alen ||
		       align_alen + extsz > MAXEXTLEN);
L
Linus Torvalds 已提交
3364 3365
	}

C
Christoph Hellwig 已提交
3366
#ifdef DEBUG
3367 3368 3369 3370 3371
	if (!eof && gotp->br_startoff != NULLFILEOFF)
		ASSERT(align_off + align_alen <= gotp->br_startoff);
	if (prevp->br_startoff != NULLFILEOFF)
		ASSERT(align_off >= prevp->br_startoff + prevp->br_blockcount);
#endif
L
Linus Torvalds 已提交
3372

3373 3374 3375
	*lenp = align_alen;
	*offp = align_off;
	return 0;
L
Linus Torvalds 已提交
3376 3377
}

3378 3379
#define XFS_ALLOC_GAP_UNITS	4

D
Dave Chinner 已提交
3380
void
3381
xfs_bmap_adjacent(
D
Dave Chinner 已提交
3382
	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
L
Linus Torvalds 已提交
3383
{
3384 3385 3386 3387 3388
	xfs_fsblock_t	adjust;		/* adjustment to block numbers */
	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */
	xfs_mount_t	*mp;		/* mount point structure */
	int		nullfb;		/* true if ap->firstblock isn't set */
	int		rt;		/* true if inode is realtime */
L
Linus Torvalds 已提交
3389

3390 3391 3392 3393 3394 3395
#define	ISVALID(x,y)	\
	(rt ? \
		(x) < mp->m_sb.sb_rblocks : \
		XFS_FSB_TO_AGNO(mp, x) == XFS_FSB_TO_AGNO(mp, y) && \
		XFS_FSB_TO_AGNO(mp, x) < mp->m_sb.sb_agcount && \
		XFS_FSB_TO_AGBNO(mp, x) < mp->m_sb.sb_agblocks)
L
Linus Torvalds 已提交
3396

3397 3398
	mp = ap->ip->i_mount;
	nullfb = *ap->firstblock == NULLFSBLOCK;
3399 3400
	rt = XFS_IS_REALTIME_INODE(ap->ip) &&
		xfs_alloc_is_userdata(ap->datatype);
3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466
	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, *ap->firstblock);
	/*
	 * If allocating at eof, and there's a previous real block,
	 * try to use its last block as our starting point.
	 */
	if (ap->eof && ap->prev.br_startoff != NULLFILEOFF &&
	    !isnullstartblock(ap->prev.br_startblock) &&
	    ISVALID(ap->prev.br_startblock + ap->prev.br_blockcount,
		    ap->prev.br_startblock)) {
		ap->blkno = ap->prev.br_startblock + ap->prev.br_blockcount;
		/*
		 * Adjust for the gap between prevp and us.
		 */
		adjust = ap->offset -
			(ap->prev.br_startoff + ap->prev.br_blockcount);
		if (adjust &&
		    ISVALID(ap->blkno + adjust, ap->prev.br_startblock))
			ap->blkno += adjust;
	}
	/*
	 * If not at eof, then compare the two neighbor blocks.
	 * Figure out whether either one gives us a good starting point,
	 * and pick the better one.
	 */
	else if (!ap->eof) {
		xfs_fsblock_t	gotbno;		/* right side block number */
		xfs_fsblock_t	gotdiff=0;	/* right side difference */
		xfs_fsblock_t	prevbno;	/* left side block number */
		xfs_fsblock_t	prevdiff=0;	/* left side difference */

		/*
		 * If there's a previous (left) block, select a requested
		 * start block based on it.
		 */
		if (ap->prev.br_startoff != NULLFILEOFF &&
		    !isnullstartblock(ap->prev.br_startblock) &&
		    (prevbno = ap->prev.br_startblock +
			       ap->prev.br_blockcount) &&
		    ISVALID(prevbno, ap->prev.br_startblock)) {
			/*
			 * Calculate gap to end of previous block.
			 */
			adjust = prevdiff = ap->offset -
				(ap->prev.br_startoff +
				 ap->prev.br_blockcount);
			/*
			 * Figure the startblock based on the previous block's
			 * end and the gap size.
			 * Heuristic!
			 * If the gap is large relative to the piece we're
			 * allocating, or using it gives us an invalid block
			 * number, then just use the end of the previous block.
			 */
			if (prevdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
			    ISVALID(prevbno + prevdiff,
				    ap->prev.br_startblock))
				prevbno += adjust;
			else
				prevdiff += adjust;
			/*
			 * If the firstblock forbids it, can't use it,
			 * must use default.
			 */
			if (!rt && !nullfb &&
			    XFS_FSB_TO_AGNO(mp, prevbno) != fb_agno)
				prevbno = NULLFSBLOCK;
L
Linus Torvalds 已提交
3467
		}
3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524
		/*
		 * No previous block or can't follow it, just default.
		 */
		else
			prevbno = NULLFSBLOCK;
		/*
		 * If there's a following (right) block, select a requested
		 * start block based on it.
		 */
		if (!isnullstartblock(ap->got.br_startblock)) {
			/*
			 * Calculate gap to start of next block.
			 */
			adjust = gotdiff = ap->got.br_startoff - ap->offset;
			/*
			 * Figure the startblock based on the next block's
			 * start and the gap size.
			 */
			gotbno = ap->got.br_startblock;
			/*
			 * Heuristic!
			 * If the gap is large relative to the piece we're
			 * allocating, or using it gives us an invalid block
			 * number, then just use the start of the next block
			 * offset by our length.
			 */
			if (gotdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
			    ISVALID(gotbno - gotdiff, gotbno))
				gotbno -= adjust;
			else if (ISVALID(gotbno - ap->length, gotbno)) {
				gotbno -= ap->length;
				gotdiff += adjust - ap->length;
			} else
				gotdiff += adjust;
			/*
			 * If the firstblock forbids it, can't use it,
			 * must use default.
			 */
			if (!rt && !nullfb &&
			    XFS_FSB_TO_AGNO(mp, gotbno) != fb_agno)
				gotbno = NULLFSBLOCK;
		}
		/*
		 * No next block, just default.
		 */
		else
			gotbno = NULLFSBLOCK;
		/*
		 * If both valid, pick the better one, else the only good
		 * one, else ap->blkno is already set (to 0 or the inode block).
		 */
		if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK)
			ap->blkno = prevdiff <= gotdiff ? prevbno : gotbno;
		else if (prevbno != NULLFSBLOCK)
			ap->blkno = prevbno;
		else if (gotbno != NULLFSBLOCK)
			ap->blkno = gotbno;
L
Linus Torvalds 已提交
3525
	}
3526
#undef ISVALID
L
Linus Torvalds 已提交
3527 3528
}

3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552
static int
xfs_bmap_longest_free_extent(
	struct xfs_trans	*tp,
	xfs_agnumber_t		ag,
	xfs_extlen_t		*blen,
	int			*notinit)
{
	struct xfs_mount	*mp = tp->t_mountp;
	struct xfs_perag	*pag;
	xfs_extlen_t		longest;
	int			error = 0;

	pag = xfs_perag_get(mp, ag);
	if (!pag->pagf_init) {
		error = xfs_alloc_pagf_init(mp, tp, ag, XFS_ALLOC_FLAG_TRYLOCK);
		if (error)
			goto out;

		if (!pag->pagf_init) {
			*notinit = 1;
			goto out;
		}
	}

3553
	longest = xfs_alloc_longest_free_extent(mp, pag,
3554 3555
				xfs_alloc_min_freelist(mp, pag),
				xfs_ag_resv_needed(pag, XFS_AG_RESV_NONE));
3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591
	if (*blen < longest)
		*blen = longest;

out:
	xfs_perag_put(pag);
	return error;
}

static void
xfs_bmap_select_minlen(
	struct xfs_bmalloca	*ap,
	struct xfs_alloc_arg	*args,
	xfs_extlen_t		*blen,
	int			notinit)
{
	if (notinit || *blen < ap->minlen) {
		/*
		 * Since we did a BUF_TRYLOCK above, it is possible that
		 * there is space for this request.
		 */
		args->minlen = ap->minlen;
	} else if (*blen < args->maxlen) {
		/*
		 * If the best seen length is less than the request length,
		 * use the best as the minimum.
		 */
		args->minlen = *blen;
	} else {
		/*
		 * Otherwise we've seen an extent as big as maxlen, use that
		 * as the minimum.
		 */
		args->minlen = args->maxlen;
	}
}

3592
STATIC int
3593 3594 3595 3596
xfs_bmap_btalloc_nullfb(
	struct xfs_bmalloca	*ap,
	struct xfs_alloc_arg	*args,
	xfs_extlen_t		*blen)
3597
{
3598 3599 3600
	struct xfs_mount	*mp = ap->ip->i_mount;
	xfs_agnumber_t		ag, startag;
	int			notinit = 0;
3601 3602
	int			error;

3603
	args->type = XFS_ALLOCTYPE_START_BNO;
3604
	args->total = ap->total;
3605

3606 3607 3608
	startag = ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
	if (startag == NULLAGNUMBER)
		startag = ag = 0;
3609

3610
	while (*blen < args->maxlen) {
3611 3612 3613 3614
		error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
						     &notinit);
		if (error)
			return error;
3615

3616 3617 3618 3619 3620
		if (++ag == mp->m_sb.sb_agcount)
			ag = 0;
		if (ag == startag)
			break;
	}
3621

3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660
	xfs_bmap_select_minlen(ap, args, blen, notinit);
	return 0;
}

STATIC int
xfs_bmap_btalloc_filestreams(
	struct xfs_bmalloca	*ap,
	struct xfs_alloc_arg	*args,
	xfs_extlen_t		*blen)
{
	struct xfs_mount	*mp = ap->ip->i_mount;
	xfs_agnumber_t		ag;
	int			notinit = 0;
	int			error;

	args->type = XFS_ALLOCTYPE_NEAR_BNO;
	args->total = ap->total;

	ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
	if (ag == NULLAGNUMBER)
		ag = 0;

	error = xfs_bmap_longest_free_extent(args->tp, ag, blen, &notinit);
	if (error)
		return error;

	if (*blen < args->maxlen) {
		error = xfs_filestream_new_ag(ap, &ag);
		if (error)
			return error;

		error = xfs_bmap_longest_free_extent(args->tp, ag, blen,
						     &notinit);
		if (error)
			return error;

	}

	xfs_bmap_select_minlen(ap, args, blen, notinit);
3661 3662

	/*
3663 3664
	 * Set the failure fallback case to look in the selected AG as stream
	 * may have moved.
3665
	 */
3666
	ap->blkno = args->fsbno = XFS_AGB_TO_FSB(mp, ag, 0);
3667 3668 3669
	return 0;
}

3670 3671
STATIC int
xfs_bmap_btalloc(
D
Dave Chinner 已提交
3672
	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3673
{
3674 3675
	xfs_mount_t	*mp;		/* mount point structure */
	xfs_alloctype_t	atype = 0;	/* type for allocation routines */
3676
	xfs_extlen_t	align = 0;	/* minimum allocation alignment */
3677 3678 3679 3680 3681 3682 3683 3684 3685
	xfs_agnumber_t	fb_agno;	/* ag number of ap->firstblock */
	xfs_agnumber_t	ag;
	xfs_alloc_arg_t	args;
	xfs_extlen_t	blen;
	xfs_extlen_t	nextminlen = 0;
	int		nullfb;		/* true if ap->firstblock isn't set */
	int		isaligned;
	int		tryagain;
	int		error;
3686
	int		stripe_align;
3687

3688
	ASSERT(ap->length);
3689

3690
	mp = ap->ip->i_mount;
3691 3692 3693 3694 3695 3696 3697 3698

	/* stripe alignment for allocation is determined by mount parameters */
	stripe_align = 0;
	if (mp->m_swidth && (mp->m_flags & XFS_MOUNT_SWALLOC))
		stripe_align = mp->m_swidth;
	else if (mp->m_dalign)
		stripe_align = mp->m_dalign;

3699 3700 3701
	if (ap->flags & XFS_BMAPI_COWFORK)
		align = xfs_get_cowextsz_hint(ap->ip);
	else if (xfs_alloc_is_userdata(ap->datatype))
3702
		align = xfs_get_extsz_hint(ap->ip);
3703 3704 3705 3706 3707 3708
	if (unlikely(align)) {
		error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
						align, 0, ap->eof, 0, ap->conv,
						&ap->offset, &ap->length);
		ASSERT(!error);
		ASSERT(ap->length);
3709
	}
3710 3711


3712 3713 3714
	nullfb = *ap->firstblock == NULLFSBLOCK;
	fb_agno = nullfb ? NULLAGNUMBER : XFS_FSB_TO_AGNO(mp, *ap->firstblock);
	if (nullfb) {
3715 3716
		if (xfs_alloc_is_userdata(ap->datatype) &&
		    xfs_inode_is_filestream(ap->ip)) {
3717 3718 3719 3720 3721 3722 3723 3724
			ag = xfs_filestream_lookup_ag(ap->ip);
			ag = (ag != NULLAGNUMBER) ? ag : 0;
			ap->blkno = XFS_AGB_TO_FSB(mp, ag, 0);
		} else {
			ap->blkno = XFS_INO_TO_FSB(mp, ap->ip->i_ino);
		}
	} else
		ap->blkno = *ap->firstblock;
3725

3726
	xfs_bmap_adjacent(ap);
3727

3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743
	/*
	 * If allowed, use ap->blkno; otherwise must use firstblock since
	 * it's in the right allocation group.
	 */
	if (nullfb || XFS_FSB_TO_AGNO(mp, ap->blkno) == fb_agno)
		;
	else
		ap->blkno = *ap->firstblock;
	/*
	 * Normal allocation, done through xfs_alloc_vextent.
	 */
	tryagain = isaligned = 0;
	memset(&args, 0, sizeof(args));
	args.tp = ap->tp;
	args.mp = mp;
	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 3749 3750
	args.firstblock = *ap->firstblock;
	blen = 0;
	if (nullfb) {
3751 3752 3753 3754 3755
		/*
		 * Search for an allocation group with a single extent large
		 * enough for the request.  If one isn't found, then adjust
		 * the minimum allocation size to the largest space found.
		 */
3756 3757
		if (xfs_alloc_is_userdata(ap->datatype) &&
		    xfs_inode_is_filestream(ap->ip))
3758 3759 3760
			error = xfs_bmap_btalloc_filestreams(ap, &args, &blen);
		else
			error = xfs_bmap_btalloc_nullfb(ap, &args, &blen);
3761 3762
		if (error)
			return error;
3763
	} else if (ap->dfops->dop_low) {
3764 3765 3766 3767 3768 3769 3770 3771 3772
		if (xfs_inode_is_filestream(ap->ip))
			args.type = XFS_ALLOCTYPE_FIRST_AG;
		else
			args.type = XFS_ALLOCTYPE_START_BNO;
		args.total = args.minlen = ap->minlen;
	} else {
		args.type = XFS_ALLOCTYPE_NEAR_BNO;
		args.total = ap->total;
		args.minlen = ap->minlen;
3773
	}
3774 3775 3776 3777 3778
	/* apply extent size hints if obtained earlier */
	if (unlikely(align)) {
		args.prod = align;
		if ((args.mod = (xfs_extlen_t)do_mod(ap->offset, args.prod)))
			args.mod = (xfs_extlen_t)(args.prod - args.mod);
3779
	} else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
3780 3781 3782
		args.prod = 1;
		args.mod = 0;
	} else {
3783
		args.prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
3784 3785
		if ((args.mod = (xfs_extlen_t)(do_mod(ap->offset, args.prod))))
			args.mod = (xfs_extlen_t)(args.prod - args.mod);
3786
	}
3787
	/*
3788 3789 3790 3791 3792 3793 3794
	 * If we are not low on available data blocks, and the
	 * underlying logical volume manager is a stripe, and
	 * the file offset is zero then try to allocate data
	 * blocks on stripe unit boundary.
	 * NOTE: ap->aeof is only set if the allocation length
	 * is >= the stripe unit and the allocation offset is
	 * at the end of file.
3795
	 */
3796
	if (!ap->dfops->dop_low && ap->aeof) {
3797
		if (!ap->offset) {
3798
			args.alignment = stripe_align;
3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822
			atype = args.type;
			isaligned = 1;
			/*
			 * Adjust for alignment
			 */
			if (blen > args.alignment && blen <= args.maxlen)
				args.minlen = blen - args.alignment;
			args.minalignslop = 0;
		} else {
			/*
			 * First try an exact bno allocation.
			 * If it fails then do a near or start bno
			 * allocation with alignment turned on.
			 */
			atype = args.type;
			tryagain = 1;
			args.type = XFS_ALLOCTYPE_THIS_BNO;
			args.alignment = 1;
			/*
			 * Compute the minlen+alignment for the
			 * next case.  Set slop so that the value
			 * of minlen+alignment+slop doesn't go up
			 * between the calls.
			 */
3823 3824
			if (blen > stripe_align && blen <= args.maxlen)
				nextminlen = blen - stripe_align;
3825 3826
			else
				nextminlen = args.minlen;
3827
			if (nextminlen + stripe_align > args.minlen + 1)
3828
				args.minalignslop =
3829
					nextminlen + stripe_align -
3830 3831 3832
					args.minlen - 1;
			else
				args.minalignslop = 0;
3833 3834
		}
	} else {
3835 3836
		args.alignment = 1;
		args.minalignslop = 0;
3837
	}
3838 3839
	args.minleft = ap->minleft;
	args.wasdel = ap->wasdel;
3840
	args.resv = XFS_AG_RESV_NONE;
3841 3842
	args.datatype = ap->datatype;
	if (ap->datatype & XFS_ALLOC_USERDATA_ZERO)
3843 3844 3845 3846
		args.ip = ap->ip;

	error = xfs_alloc_vextent(&args);
	if (error)
3847
		return error;
3848

3849 3850 3851 3852 3853 3854 3855
	if (tryagain && args.fsbno == NULLFSBLOCK) {
		/*
		 * Exact allocation failed. Now try with alignment
		 * turned on.
		 */
		args.type = atype;
		args.fsbno = ap->blkno;
3856
		args.alignment = stripe_align;
3857 3858 3859 3860 3861
		args.minlen = nextminlen;
		args.minalignslop = 0;
		isaligned = 1;
		if ((error = xfs_alloc_vextent(&args)))
			return error;
3862
	}
3863 3864 3865 3866 3867 3868 3869 3870 3871
	if (isaligned && args.fsbno == NULLFSBLOCK) {
		/*
		 * allocation failed, so turn off alignment and
		 * try again.
		 */
		args.type = atype;
		args.fsbno = ap->blkno;
		args.alignment = 0;
		if ((error = xfs_alloc_vextent(&args)))
3872 3873
			return error;
	}
3874 3875 3876 3877 3878 3879 3880
	if (args.fsbno == NULLFSBLOCK && nullfb &&
	    args.minlen > ap->minlen) {
		args.minlen = ap->minlen;
		args.type = XFS_ALLOCTYPE_START_BNO;
		args.fsbno = ap->blkno;
		if ((error = xfs_alloc_vextent(&args)))
			return error;
3881
	}
3882 3883 3884 3885 3886 3887 3888
	if (args.fsbno == NULLFSBLOCK && nullfb) {
		args.fsbno = 0;
		args.type = XFS_ALLOCTYPE_FIRST_AG;
		args.total = ap->minlen;
		args.minleft = 0;
		if ((error = xfs_alloc_vextent(&args)))
			return error;
3889
		ap->dfops->dop_low = true;
3890 3891 3892 3893 3894 3895 3896 3897 3898
	}
	if (args.fsbno != NULLFSBLOCK) {
		/*
		 * check the allocation happened at the same or higher AG than
		 * the first block that was allocated.
		 */
		ASSERT(*ap->firstblock == NULLFSBLOCK ||
		       XFS_FSB_TO_AGNO(mp, *ap->firstblock) ==
		       XFS_FSB_TO_AGNO(mp, args.fsbno) ||
3899
		       (ap->dfops->dop_low &&
3900 3901
			XFS_FSB_TO_AGNO(mp, *ap->firstblock) <
			XFS_FSB_TO_AGNO(mp, args.fsbno)));
3902

3903 3904 3905 3906
		ap->blkno = args.fsbno;
		if (*ap->firstblock == NULLFSBLOCK)
			*ap->firstblock = args.fsbno;
		ASSERT(nullfb || fb_agno == args.agno ||
3907
		       (ap->dfops->dop_low && fb_agno < args.agno));
3908
		ap->length = args.len;
3909 3910
		if (!(ap->flags & XFS_BMAPI_COWFORK))
			ap->ip->i_d.di_nblocks += args.len;
3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927
		xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
		if (ap->wasdel)
			ap->ip->i_delayed_blks -= args.len;
		/*
		 * Adjust the disk quota also. This was reserved
		 * earlier.
		 */
		xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
			ap->wasdel ? XFS_TRANS_DQ_DELBCOUNT :
					XFS_TRANS_DQ_BCOUNT,
			(long) args.len);
	} else {
		ap->blkno = NULLFSBLOCK;
		ap->length = 0;
	}
	return 0;
}
3928

3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982
/*
 * For a remap operation, just "allocate" an extent at the address that the
 * caller passed in, and ensure that the AGFL is the right size.  The caller
 * will then map the "allocated" extent into the file somewhere.
 */
STATIC int
xfs_bmap_remap_alloc(
	struct xfs_bmalloca	*ap)
{
	struct xfs_trans	*tp = ap->tp;
	struct xfs_mount	*mp = tp->t_mountp;
	xfs_agblock_t		bno;
	struct xfs_alloc_arg	args;
	int			error;

	/*
	 * validate that the block number is legal - the enables us to detect
	 * and handle a silent filesystem corruption rather than crashing.
	 */
	memset(&args, 0, sizeof(struct xfs_alloc_arg));
	args.tp = ap->tp;
	args.mp = ap->tp->t_mountp;
	bno = *ap->firstblock;
	args.agno = XFS_FSB_TO_AGNO(mp, bno);
	args.agbno = XFS_FSB_TO_AGBNO(mp, bno);
	if (args.agno >= mp->m_sb.sb_agcount ||
	    args.agbno >= mp->m_sb.sb_agblocks)
		return -EFSCORRUPTED;

	/* "Allocate" the extent from the range we passed in. */
	trace_xfs_bmap_remap_alloc(ap->ip, *ap->firstblock, ap->length);
	ap->blkno = bno;
	ap->ip->i_d.di_nblocks += ap->length;
	xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);

	/* Fix the freelist, like a real allocator does. */
	args.datatype = ap->datatype;
	args.pag = xfs_perag_get(args.mp, args.agno);
	ASSERT(args.pag);

	/*
	 * The freelist fixing code will decline the allocation if
	 * the size and shape of the free space doesn't allow for
	 * allocating the extent and updating all the metadata that
	 * happens during an allocation.  We're remapping, not
	 * allocating, so skip that check by pretending to be freeing.
	 */
	error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING);
	xfs_perag_put(args.pag);
	if (error)
		trace_xfs_bmap_remap_alloc_error(ap->ip, error, _RET_IP_);
	return error;
}

3983 3984 3985 3986 3987 3988
/*
 * xfs_bmap_alloc is called by xfs_bmapi to allocate an extent for a file.
 * It figures out where to ask the underlying allocator to put the new extent.
 */
STATIC int
xfs_bmap_alloc(
D
Dave Chinner 已提交
3989
	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
3990
{
3991 3992
	if (ap->flags & XFS_BMAPI_REMAP)
		return xfs_bmap_remap_alloc(ap);
3993 3994
	if (XFS_IS_REALTIME_INODE(ap->ip) &&
	    xfs_alloc_is_userdata(ap->datatype))
3995 3996 3997
		return xfs_bmap_rtalloc(ap);
	return xfs_bmap_btalloc(ap);
}
3998

D
Darrick J. Wong 已提交
3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031
/* Trim extent to fit a logical block range. */
void
xfs_trim_extent(
	struct xfs_bmbt_irec	*irec,
	xfs_fileoff_t		bno,
	xfs_filblks_t		len)
{
	xfs_fileoff_t		distance;
	xfs_fileoff_t		end = bno + len;

	if (irec->br_startoff + irec->br_blockcount <= bno ||
	    irec->br_startoff >= end) {
		irec->br_blockcount = 0;
		return;
	}

	if (irec->br_startoff < bno) {
		distance = bno - irec->br_startoff;
		if (isnullstartblock(irec->br_startblock))
			irec->br_startblock = DELAYSTARTBLOCK;
		if (irec->br_startblock != DELAYSTARTBLOCK &&
		    irec->br_startblock != HOLESTARTBLOCK)
			irec->br_startblock += distance;
		irec->br_startoff += distance;
		irec->br_blockcount -= distance;
	}

	if (end < irec->br_startoff + irec->br_blockcount) {
		distance = irec->br_startoff + irec->br_blockcount - end;
		irec->br_blockcount -= distance;
	}
}

4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 4052
/*
 * Trim the returned map to the required bounds
 */
STATIC void
xfs_bmapi_trim_map(
	struct xfs_bmbt_irec	*mval,
	struct xfs_bmbt_irec	*got,
	xfs_fileoff_t		*bno,
	xfs_filblks_t		len,
	xfs_fileoff_t		obno,
	xfs_fileoff_t		end,
	int			n,
	int			flags)
{
	if ((flags & XFS_BMAPI_ENTIRE) ||
	    got->br_startoff + got->br_blockcount <= obno) {
		*mval = *got;
		if (isnullstartblock(got->br_startblock))
			mval->br_startblock = DELAYSTARTBLOCK;
		return;
	}
4053

4054 4055 4056 4057 4058 4059 4060 4061 4062 4063
	if (obno > *bno)
		*bno = obno;
	ASSERT((*bno >= obno) || (n == 0));
	ASSERT(*bno < end);
	mval->br_startoff = *bno;
	if (isnullstartblock(got->br_startblock))
		mval->br_startblock = DELAYSTARTBLOCK;
	else
		mval->br_startblock = got->br_startblock +
					(*bno - got->br_startoff);
4064
	/*
4065 4066 4067 4068 4069
	 * Return the minimum of what we got and what we asked for for
	 * the length.  We can use the len variable here because it is
	 * modified below and we could have been there before coming
	 * here if the first part of the allocation didn't overlap what
	 * was asked for.
4070
	 */
4071 4072 4073 4074 4075
	mval->br_blockcount = XFS_FILBLKS_MIN(end - *bno,
			got->br_blockcount - (*bno - got->br_startoff));
	mval->br_state = got->br_state;
	ASSERT(mval->br_blockcount <= len);
	return;
4076 4077
}

4078 4079 4080 4081 4082 4083 4084 4085 4086 4087 4088 4089
/*
 * Update and validate the extent map to return
 */
STATIC void
xfs_bmapi_update_map(
	struct xfs_bmbt_irec	**map,
	xfs_fileoff_t		*bno,
	xfs_filblks_t		*len,
	xfs_fileoff_t		obno,
	xfs_fileoff_t		end,
	int			*n,
	int			flags)
4090
{
4091
	xfs_bmbt_irec_t	*mval = *map;
4092

4093 4094 4095 4096
	ASSERT((flags & XFS_BMAPI_ENTIRE) ||
	       ((mval->br_startoff + mval->br_blockcount) <= end));
	ASSERT((flags & XFS_BMAPI_ENTIRE) || (mval->br_blockcount <= *len) ||
	       (mval->br_startoff < obno));
4097

4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 4130
	*bno = mval->br_startoff + mval->br_blockcount;
	*len = end - *bno;
	if (*n > 0 && mval->br_startoff == mval[-1].br_startoff) {
		/* update previous map with new information */
		ASSERT(mval->br_startblock == mval[-1].br_startblock);
		ASSERT(mval->br_blockcount > mval[-1].br_blockcount);
		ASSERT(mval->br_state == mval[-1].br_state);
		mval[-1].br_blockcount = mval->br_blockcount;
		mval[-1].br_state = mval->br_state;
	} else if (*n > 0 && mval->br_startblock != DELAYSTARTBLOCK &&
		   mval[-1].br_startblock != DELAYSTARTBLOCK &&
		   mval[-1].br_startblock != HOLESTARTBLOCK &&
		   mval->br_startblock == mval[-1].br_startblock +
					  mval[-1].br_blockcount &&
		   ((flags & XFS_BMAPI_IGSTATE) ||
			mval[-1].br_state == mval->br_state)) {
		ASSERT(mval->br_startoff ==
		       mval[-1].br_startoff + mval[-1].br_blockcount);
		mval[-1].br_blockcount += mval->br_blockcount;
	} else if (*n > 0 &&
		   mval->br_startblock == DELAYSTARTBLOCK &&
		   mval[-1].br_startblock == DELAYSTARTBLOCK &&
		   mval->br_startoff ==
		   mval[-1].br_startoff + mval[-1].br_blockcount) {
		mval[-1].br_blockcount += mval->br_blockcount;
		mval[-1].br_state = mval->br_state;
	} else if (!((*n == 0) &&
		     ((mval->br_startoff + mval->br_blockcount) <=
		      obno))) {
		mval++;
		(*n)++;
	}
	*map = mval;
4131 4132 4133
}

/*
4134
 * Map file blocks to filesystem blocks without allocation.
4135 4136
 */
int
4137 4138 4139
xfs_bmapi_read(
	struct xfs_inode	*ip,
	xfs_fileoff_t		bno,
4140
	xfs_filblks_t		len,
4141 4142
	struct xfs_bmbt_irec	*mval,
	int			*nmap,
4143
	int			flags)
4144
{
4145 4146 4147 4148 4149 4150 4151 4152 4153 4154
	struct xfs_mount	*mp = ip->i_mount;
	struct xfs_ifork	*ifp;
	struct xfs_bmbt_irec	got;
	struct xfs_bmbt_irec	prev;
	xfs_fileoff_t		obno;
	xfs_fileoff_t		end;
	xfs_extnum_t		lastx;
	int			error;
	int			eof;
	int			n = 0;
D
Darrick J. Wong 已提交
4155
	int			whichfork = xfs_bmapi_whichfork(flags);
4156

4157 4158
	ASSERT(*nmap >= 1);
	ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK|XFS_BMAPI_ENTIRE|
D
Darrick J. Wong 已提交
4159
			   XFS_BMAPI_IGSTATE|XFS_BMAPI_COWFORK)));
4160
	ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED|XFS_ILOCK_EXCL));
4161

4162 4163 4164 4165 4166
	if (unlikely(XFS_TEST_ERROR(
	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
		XFS_ERROR_REPORT("xfs_bmapi_read", XFS_ERRLEVEL_LOW, mp);
D
Dave Chinner 已提交
4167
		return -EFSCORRUPTED;
4168
	}
4169

4170
	if (XFS_FORCED_SHUTDOWN(mp))
D
Dave Chinner 已提交
4171
		return -EIO;
4172

4173
	XFS_STATS_INC(mp, xs_blk_mapr);
4174 4175 4176

	ifp = XFS_IFORK_PTR(ip, whichfork);

D
Darrick J. Wong 已提交
4177 4178 4179 4180 4181 4182 4183 4184 4185 4186
	/* No CoW fork?  Return a hole. */
	if (whichfork == XFS_COW_FORK && !ifp) {
		mval->br_startoff = bno;
		mval->br_startblock = HOLESTARTBLOCK;
		mval->br_blockcount = len;
		mval->br_state = XFS_EXT_NORM;
		*nmap = 1;
		return 0;
	}

4187 4188 4189 4190
	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
		error = xfs_iread_extents(NULL, ip, whichfork);
		if (error)
			return error;
4191 4192
	}

4193 4194 4195
	xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got, &prev);
	end = bno + len;
	obno = bno;
4196

4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212 4213
	while (bno < end && n < *nmap) {
		/* Reading past eof, act as though there's a hole up to end. */
		if (eof)
			got.br_startoff = end;
		if (got.br_startoff > bno) {
			/* Reading in a hole.  */
			mval->br_startoff = bno;
			mval->br_startblock = HOLESTARTBLOCK;
			mval->br_blockcount =
				XFS_FILBLKS_MIN(len, got.br_startoff - bno);
			mval->br_state = XFS_EXT_NORM;
			bno += mval->br_blockcount;
			len -= mval->br_blockcount;
			mval++;
			n++;
			continue;
		}
4214

4215 4216 4217 4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229
		/* set up the extent map to return. */
		xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags);
		xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);

		/* If we're done, stop now. */
		if (bno >= end || n >= *nmap)
			break;

		/* Else go on to the next record. */
		if (++lastx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t))
			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, lastx), &got);
		else
			eof = 1;
	}
	*nmap = n;
4230 4231 4232
	return 0;
}

4233
int
4234 4235
xfs_bmapi_reserve_delalloc(
	struct xfs_inode	*ip,
4236
	int			whichfork,
4237 4238 4239 4240 4241 4242
	xfs_fileoff_t		aoff,
	xfs_filblks_t		len,
	struct xfs_bmbt_irec	*got,
	struct xfs_bmbt_irec	*prev,
	xfs_extnum_t		*lastx,
	int			eof)
L
Linus Torvalds 已提交
4243
{
4244
	struct xfs_mount	*mp = ip->i_mount;
4245
	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
4246 4247 4248 4249 4250
	xfs_extlen_t		alen;
	xfs_extlen_t		indlen;
	char			rt = XFS_IS_REALTIME_INODE(ip);
	xfs_extlen_t		extsz;
	int			error;
4251

4252 4253 4254
	alen = XFS_FILBLKS_MIN(len, MAXEXTLEN);
	if (!eof)
		alen = XFS_FILBLKS_MIN(alen, got->br_startoff - aoff);
L
Linus Torvalds 已提交
4255

4256
	/* Figure out the extent size, adjust alen */
4257 4258 4259 4260
	if (whichfork == XFS_COW_FORK)
		extsz = xfs_get_cowextsz_hint(ip);
	else
		extsz = xfs_get_extsz_hint(ip);
4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287
	if (extsz) {
		error = xfs_bmap_extsize_align(mp, got, prev, extsz, rt, eof,
					       1, 0, &aoff, &alen);
		ASSERT(!error);
	}

	if (rt)
		extsz = alen / mp->m_sb.sb_rextsize;

	/*
	 * Make a transaction-less quota reservation for delayed allocation
	 * blocks.  This number gets adjusted later.  We return if we haven't
	 * allocated blocks already inside this loop.
	 */
	error = xfs_trans_reserve_quota_nblks(NULL, ip, (long)alen, 0,
			rt ? XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS);
	if (error)
		return error;

	/*
	 * Split changing sb for alen and indlen since they could be coming
	 * from different places.
	 */
	indlen = (xfs_extlen_t)xfs_bmap_worst_indlen(ip, alen);
	ASSERT(indlen > 0);

	if (rt) {
D
Dave Chinner 已提交
4288
		error = xfs_mod_frextents(mp, -((int64_t)extsz));
4289
	} else {
4290
		error = xfs_mod_fdblocks(mp, -((int64_t)alen), false);
4291 4292 4293 4294 4295
	}

	if (error)
		goto out_unreserve_quota;

4296
	error = xfs_mod_fdblocks(mp, -((int64_t)indlen), false);
4297 4298 4299 4300 4301 4302 4303 4304 4305 4306
	if (error)
		goto out_unreserve_blocks;


	ip->i_delayed_blks += alen;

	got->br_startoff = aoff;
	got->br_startblock = nullstartblock(indlen);
	got->br_blockcount = alen;
	got->br_state = XFS_EXT_NORM;
4307
	xfs_bmap_add_extent_hole_delay(ip, whichfork, lastx, got);
4308 4309 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322

	/*
	 * Update our extent pointer, given that xfs_bmap_add_extent_hole_delay
	 * might have merged it into one of the neighbouring ones.
	 */
	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *lastx), got);

	ASSERT(got->br_startoff <= aoff);
	ASSERT(got->br_startoff + got->br_blockcount >= aoff + alen);
	ASSERT(isnullstartblock(got->br_startblock));
	ASSERT(got->br_state == XFS_EXT_NORM);
	return 0;

out_unreserve_blocks:
	if (rt)
D
Dave Chinner 已提交
4323
		xfs_mod_frextents(mp, extsz);
4324
	else
4325
		xfs_mod_fdblocks(mp, alen, false);
4326 4327 4328 4329 4330 4331 4332
out_unreserve_quota:
	if (XFS_IS_QUOTA_ON(mp))
		xfs_trans_unreserve_quota_nblks(NULL, ip, (long)alen, 0, rt ?
				XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS);
	return error;
}

4333 4334
static int
xfs_bmapi_allocate(
4335 4336 4337
	struct xfs_bmalloca	*bma)
{
	struct xfs_mount	*mp = bma->ip->i_mount;
4338
	int			whichfork = xfs_bmapi_whichfork(bma->flags);
4339 4340 4341 4342 4343 4344
	struct xfs_ifork	*ifp = XFS_IFORK_PTR(bma->ip, whichfork);
	int			tmp_logflags = 0;
	int			error;

	ASSERT(bma->length > 0);

L
Linus Torvalds 已提交
4345
	/*
4346 4347
	 * For the wasdelay case, we could also just allocate the stuff asked
	 * for in this bmap call but that wouldn't be as good.
L
Linus Torvalds 已提交
4348
	 */
4349 4350 4351 4352 4353 4354
	if (bma->wasdel) {
		bma->length = (xfs_extlen_t)bma->got.br_blockcount;
		bma->offset = bma->got.br_startoff;
		if (bma->idx != NULLEXTNUM && bma->idx) {
			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx - 1),
					 &bma->prev);
L
Linus Torvalds 已提交
4355
		}
4356 4357 4358 4359 4360
	} else {
		bma->length = XFS_FILBLKS_MIN(bma->length, MAXEXTLEN);
		if (!bma->eof)
			bma->length = XFS_FILBLKS_MIN(bma->length,
					bma->got.br_startoff - bma->offset);
L
Linus Torvalds 已提交
4361 4362
	}

4363
	/*
4364 4365 4366 4367
	 * Set the data type being allocated. For the data fork, the first data
	 * in the file is treated differently to all other allocations. For the
	 * attribute fork, we only need to ensure the allocated range is not on
	 * the busy list.
4368 4369
	 */
	if (!(bma->flags & XFS_BMAPI_METADATA)) {
4370 4371 4372 4373 4374 4375 4376
		bma->datatype = XFS_ALLOC_NOBUSY;
		if (whichfork == XFS_DATA_FORK) {
			if (bma->offset == 0)
				bma->datatype |= XFS_ALLOC_INITIAL_USER_DATA;
			else
				bma->datatype |= XFS_ALLOC_USERDATA;
		}
4377
		if (bma->flags & XFS_BMAPI_ZERO)
4378
			bma->datatype |= XFS_ALLOC_USERDATA_ZERO;
4379
	}
L
Linus Torvalds 已提交
4380

4381
	bma->minlen = (bma->flags & XFS_BMAPI_CONTIG) ? bma->length : 1;
C
Christoph Hellwig 已提交
4382

4383 4384 4385 4386 4387 4388 4389 4390 4391
	/*
	 * Only want to do the alignment at the eof if it is userdata and
	 * allocation length is larger than a stripe unit.
	 */
	if (mp->m_dalign && bma->length >= mp->m_dalign &&
	    !(bma->flags & XFS_BMAPI_METADATA) && whichfork == XFS_DATA_FORK) {
		error = xfs_bmap_isaeof(bma, whichfork);
		if (error)
			return error;
L
Linus Torvalds 已提交
4392
	}
4393

4394 4395
	error = xfs_bmap_alloc(bma);
	if (error)
L
Linus Torvalds 已提交
4396
		return error;
4397

4398
	if (bma->dfops->dop_low)
4399 4400 4401 4402
		bma->minleft = 0;
	if (bma->cur)
		bma->cur->bc_private.b.firstblock = *bma->firstblock;
	if (bma->blkno == NULLFSBLOCK)
L
Linus Torvalds 已提交
4403
		return 0;
4404 4405 4406
	if ((ifp->if_flags & XFS_IFBROOT) && !bma->cur) {
		bma->cur = xfs_bmbt_init_cursor(mp, bma->tp, bma->ip, whichfork);
		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4407
		bma->cur->bc_private.b.dfops = bma->dfops;
L
Linus Torvalds 已提交
4408
	}
4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422
	/*
	 * Bump the number of extents we've allocated
	 * in this call.
	 */
	bma->nallocs++;

	if (bma->cur)
		bma->cur->bc_private.b.flags =
			bma->wasdel ? XFS_BTCUR_BPRV_WASDEL : 0;

	bma->got.br_startoff = bma->offset;
	bma->got.br_startblock = bma->blkno;
	bma->got.br_blockcount = bma->length;
	bma->got.br_state = XFS_EXT_NORM;
4423

L
Linus Torvalds 已提交
4424
	/*
4425 4426
	 * A wasdelay extent has been initialized, so shouldn't be flagged
	 * as unwritten.
L
Linus Torvalds 已提交
4427
	 */
4428 4429 4430 4431 4432
	if (!bma->wasdel && (bma->flags & XFS_BMAPI_PREALLOC) &&
	    xfs_sb_version_hasextflgbit(&mp->m_sb))
		bma->got.br_state = XFS_EXT_UNWRITTEN;

	if (bma->wasdel)
4433
		error = xfs_bmap_add_extent_delay_real(bma, whichfork);
4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462
	else
		error = xfs_bmap_add_extent_hole_real(bma, whichfork);

	bma->logflags |= tmp_logflags;
	if (error)
		return error;

	/*
	 * Update our extent pointer, given that xfs_bmap_add_extent_delay_real
	 * or xfs_bmap_add_extent_hole_real might have merged it into one of
	 * the neighbouring ones.
	 */
	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx), &bma->got);

	ASSERT(bma->got.br_startoff <= bma->offset);
	ASSERT(bma->got.br_startoff + bma->got.br_blockcount >=
	       bma->offset + bma->length);
	ASSERT(bma->got.br_state == XFS_EXT_NORM ||
	       bma->got.br_state == XFS_EXT_UNWRITTEN);
	return 0;
}

STATIC int
xfs_bmapi_convert_unwritten(
	struct xfs_bmalloca	*bma,
	struct xfs_bmbt_irec	*mval,
	xfs_filblks_t		len,
	int			flags)
{
D
Darrick J. Wong 已提交
4463
	int			whichfork = xfs_bmapi_whichfork(flags);
4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477 4478
	struct xfs_ifork	*ifp = XFS_IFORK_PTR(bma->ip, whichfork);
	int			tmp_logflags = 0;
	int			error;

	/* check if we need to do unwritten->real conversion */
	if (mval->br_state == XFS_EXT_UNWRITTEN &&
	    (flags & XFS_BMAPI_PREALLOC))
		return 0;

	/* check if we need to do real->unwritten conversion */
	if (mval->br_state == XFS_EXT_NORM &&
	    (flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT)) !=
			(XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT))
		return 0;

D
Darrick J. Wong 已提交
4479 4480
	ASSERT(whichfork != XFS_COW_FORK);

4481 4482 4483 4484 4485 4486 4487 4488
	/*
	 * Modify (by adding) the state flag, if writing.
	 */
	ASSERT(mval->br_blockcount <= len);
	if ((ifp->if_flags & XFS_IFBROOT) && !bma->cur) {
		bma->cur = xfs_bmbt_init_cursor(bma->ip->i_mount, bma->tp,
					bma->ip, whichfork);
		bma->cur->bc_private.b.firstblock = *bma->firstblock;
4489
		bma->cur->bc_private.b.dfops = bma->dfops;
L
Linus Torvalds 已提交
4490
	}
4491 4492
	mval->br_state = (mval->br_state == XFS_EXT_UNWRITTEN)
				? XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
4493

4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504
	/*
	 * Before insertion into the bmbt, zero the range being converted
	 * if required.
	 */
	if (flags & XFS_BMAPI_ZERO) {
		error = xfs_zero_extent(bma->ip, mval->br_startblock,
					mval->br_blockcount);
		if (error)
			return error;
	}

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 4510 4511 4512 4513 4514 4515 4516
	/*
	 * Log the inode core unconditionally in the unwritten extent conversion
	 * path because the conversion might not have done so (e.g., if the
	 * extent count hasn't changed). We need to make sure the inode is dirty
	 * in the transaction for the sake of fsync(), even if nothing has
	 * changed, because fsync() will not force the log for this transaction
	 * unless it sees the inode pinned.
	 */
	bma->logflags |= tmp_logflags | XFS_ILOG_CORE;
4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531
	if (error)
		return error;

	/*
	 * Update our extent pointer, given that
	 * xfs_bmap_add_extent_unwritten_real might have merged it into one
	 * of the neighbouring ones.
	 */
	xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma->idx), &bma->got);

	/*
	 * We may have combined previously unwritten space with written space,
	 * so generate another request.
	 */
	if (mval->br_blockcount < len)
D
Dave Chinner 已提交
4532
		return -EAGAIN;
4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559
	return 0;
}

/*
 * Map file blocks to filesystem blocks, and allocate blocks or convert the
 * extent state if necessary.  Details behaviour is controlled by the flags
 * parameter.  Only allocates blocks from a single allocation group, to avoid
 * locking problems.
 *
 * The returned value in "firstblock" from the first call in a transaction
 * must be remembered and presented to subsequent calls in "firstblock".
 * An upper bound for the number of blocks to be allocated is supplied to
 * the first call in "total"; if no allocation group has that many free
 * blocks then the call will fail (return NULLFSBLOCK in "firstblock").
 */
int
xfs_bmapi_write(
	struct xfs_trans	*tp,		/* transaction pointer */
	struct xfs_inode	*ip,		/* incore inode */
	xfs_fileoff_t		bno,		/* starting file offs. mapped */
	xfs_filblks_t		len,		/* length to map in file */
	int			flags,		/* XFS_BMAPI_... */
	xfs_fsblock_t		*firstblock,	/* first allocated block
						   controls a.g. for allocs */
	xfs_extlen_t		total,		/* total blocks needed */
	struct xfs_bmbt_irec	*mval,		/* output: map values */
	int			*nmap,		/* i/o: mval size/count */
4560
	struct xfs_defer_ops	*dfops)		/* i/o: list extents to free */
4561 4562 4563
{
	struct xfs_mount	*mp = ip->i_mount;
	struct xfs_ifork	*ifp;
4564
	struct xfs_bmalloca	bma = { NULL };	/* args for xfs_bmap_alloc */
4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586
	xfs_fileoff_t		end;		/* end of mapped file region */
	int			eof;		/* after the end of extents */
	int			error;		/* error return */
	int			n;		/* current extent index */
	xfs_fileoff_t		obno;		/* old block number (offset) */
	int			whichfork;	/* data or attr fork */
	char			inhole;		/* current location is hole in file */
	char			wasdelay;	/* old extent was delayed */

#ifdef DEBUG
	xfs_fileoff_t		orig_bno;	/* original block number value */
	int			orig_flags;	/* original flags arg value */
	xfs_filblks_t		orig_len;	/* original value of len arg */
	struct xfs_bmbt_irec	*orig_mval;	/* original value of mval */
	int			orig_nmap;	/* original value of *nmap */

	orig_bno = bno;
	orig_len = len;
	orig_flags = flags;
	orig_mval = mval;
	orig_nmap = *nmap;
#endif
4587
	whichfork = xfs_bmapi_whichfork(flags);
4588 4589 4590 4591 4592 4593

	ASSERT(*nmap >= 1);
	ASSERT(*nmap <= XFS_BMAP_MAX_NMAP);
	ASSERT(!(flags & XFS_BMAPI_IGSTATE));
	ASSERT(tp != NULL);
	ASSERT(len > 0);
4594
	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL);
4595
	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4596 4597 4598
	ASSERT(!(flags & XFS_BMAPI_REMAP) || whichfork == XFS_DATA_FORK);
	ASSERT(!(flags & XFS_BMAPI_PREALLOC) || !(flags & XFS_BMAPI_REMAP));
	ASSERT(!(flags & XFS_BMAPI_CONVERT) || !(flags & XFS_BMAPI_REMAP));
4599 4600
	ASSERT(!(flags & XFS_BMAPI_PREALLOC) || whichfork != XFS_COW_FORK);
	ASSERT(!(flags & XFS_BMAPI_CONVERT) || whichfork != XFS_COW_FORK);
4601

4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613
	/* zeroing is for currently only for data extents, not metadata */
	ASSERT((flags & (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO)) !=
			(XFS_BMAPI_METADATA | XFS_BMAPI_ZERO));
	/*
	 * we can allocate unwritten extents or pre-zero allocated blocks,
	 * but it makes no sense to do both at once. This would result in
	 * zeroing the unwritten extent twice, but it still being an
	 * unwritten extent....
	 */
	ASSERT((flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO)) !=
			(XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO));

4614 4615
	if (unlikely(XFS_TEST_ERROR(
	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
4616
	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
4617 4618
	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
		XFS_ERROR_REPORT("xfs_bmapi_write", XFS_ERRLEVEL_LOW, mp);
D
Dave Chinner 已提交
4619
		return -EFSCORRUPTED;
4620 4621
	}

4622
	if (XFS_FORCED_SHUTDOWN(mp))
D
Dave Chinner 已提交
4623
		return -EIO;
4624 4625 4626

	ifp = XFS_IFORK_PTR(ip, whichfork);

4627
	XFS_STATS_INC(mp, xs_blk_mapw);
4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652

	if (*firstblock == NULLFSBLOCK) {
		if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE)
			bma.minleft = be16_to_cpu(ifp->if_broot->bb_level) + 1;
		else
			bma.minleft = 1;
	} else {
		bma.minleft = 0;
	}

	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
		error = xfs_iread_extents(tp, ip, whichfork);
		if (error)
			goto error0;
	}

	xfs_bmap_search_extents(ip, bno, whichfork, &eof, &bma.idx, &bma.got,
				&bma.prev);
	n = 0;
	end = bno + len;
	obno = bno;

	bma.tp = tp;
	bma.ip = ip;
	bma.total = total;
4653
	bma.datatype = 0;
4654
	bma.dfops = dfops;
4655 4656 4657 4658 4659 4660
	bma.firstblock = firstblock;

	while (bno < end && n < *nmap) {
		inhole = eof || bma.got.br_startoff > bno;
		wasdelay = !inhole && isnullstartblock(bma.got.br_startblock);

4661 4662 4663 4664 4665
		/*
		 * Make sure we only reflink into a hole.
		 */
		if (flags & XFS_BMAPI_REMAP)
			ASSERT(inhole);
4666 4667
		if (flags & XFS_BMAPI_COWFORK)
			ASSERT(!inhole);
4668

L
Linus Torvalds 已提交
4669
		/*
4670 4671
		 * First, deal with the hole before the allocated space
		 * that we found, if any.
L
Linus Torvalds 已提交
4672
		 */
4673 4674 4675 4676 4677 4678 4679
		if (inhole || wasdelay) {
			bma.eof = eof;
			bma.conv = !!(flags & XFS_BMAPI_CONVERT);
			bma.wasdel = wasdelay;
			bma.offset = bno;
			bma.flags = flags;

L
Linus Torvalds 已提交
4680
			/*
4681 4682 4683 4684 4685
			 * There's a 32/64 bit type mismatch between the
			 * allocation length request (which can be 64 bits in
			 * length) and the bma length request, which is
			 * xfs_extlen_t and therefore 32 bits. Hence we have to
			 * check for 32-bit overflows and handle them here.
L
Linus Torvalds 已提交
4686
			 */
4687 4688 4689 4690 4691 4692 4693 4694
			if (len > (xfs_filblks_t)MAXEXTLEN)
				bma.length = MAXEXTLEN;
			else
				bma.length = len;

			ASSERT(len > 0);
			ASSERT(bma.length > 0);
			error = xfs_bmapi_allocate(&bma);
L
Linus Torvalds 已提交
4695 4696
			if (error)
				goto error0;
4697 4698
			if (bma.blkno == NULLFSBLOCK)
				break;
4699 4700 4701 4702 4703 4704 4705 4706 4707 4708 4709

			/*
			 * If this is a CoW allocation, record the data in
			 * the refcount btree for orphan recovery.
			 */
			if (whichfork == XFS_COW_FORK) {
				error = xfs_refcount_alloc_cow_extent(mp, dfops,
						bma.blkno, bma.length);
				if (error)
					goto error0;
			}
L
Linus Torvalds 已提交
4710
		}
4711 4712 4713 4714 4715 4716 4717

		/* Deal with the allocated space we found.  */
		xfs_bmapi_trim_map(mval, &bma.got, &bno, len, obno,
							end, n, flags);

		/* Execute unwritten extent conversion if necessary */
		error = xfs_bmapi_convert_unwritten(&bma, mval, len, flags);
D
Dave Chinner 已提交
4718
		if (error == -EAGAIN)
4719 4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738 4739 4740 4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786
			continue;
		if (error)
			goto error0;

		/* update the extent map to return */
		xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);

		/*
		 * If we're done, stop now.  Stop when we've allocated
		 * XFS_BMAP_MAX_NMAP extents no matter what.  Otherwise
		 * the transaction may get too big.
		 */
		if (bno >= end || n >= *nmap || bma.nallocs >= *nmap)
			break;

		/* Else go on to the next record. */
		bma.prev = bma.got;
		if (++bma.idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t)) {
			xfs_bmbt_get_all(xfs_iext_get_ext(ifp, bma.idx),
					 &bma.got);
		} else
			eof = 1;
	}
	*nmap = n;

	/*
	 * Transform from btree to extents, give it cur.
	 */
	if (xfs_bmap_wants_extents(ip, whichfork)) {
		int		tmp_logflags = 0;

		ASSERT(bma.cur);
		error = xfs_bmap_btree_to_extents(tp, ip, bma.cur,
			&tmp_logflags, whichfork);
		bma.logflags |= tmp_logflags;
		if (error)
			goto error0;
	}

	ASSERT(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE ||
	       XFS_IFORK_NEXTENTS(ip, whichfork) >
		XFS_IFORK_MAXEXT(ip, whichfork));
	error = 0;
error0:
	/*
	 * Log everything.  Do this after conversion, there's no point in
	 * logging the extent records if we've converted to btree format.
	 */
	if ((bma.logflags & xfs_ilog_fext(whichfork)) &&
	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
		bma.logflags &= ~xfs_ilog_fext(whichfork);
	else if ((bma.logflags & xfs_ilog_fbroot(whichfork)) &&
		 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
		bma.logflags &= ~xfs_ilog_fbroot(whichfork);
	/*
	 * Log whatever the flags say, even if error.  Otherwise we might miss
	 * detecting a case where the data is changed, there's an error,
	 * and it's not logged so we don't shutdown when we should.
	 */
	if (bma.logflags)
		xfs_trans_log_inode(tp, ip, bma.logflags);

	if (bma.cur) {
		if (!error) {
			ASSERT(*firstblock == NULLFSBLOCK ||
			       XFS_FSB_TO_AGNO(mp, *firstblock) ==
			       XFS_FSB_TO_AGNO(mp,
				       bma.cur->bc_private.b.firstblock) ||
4787
			       (dfops->dop_low &&
4788 4789 4790 4791
				XFS_FSB_TO_AGNO(mp, *firstblock) <
				XFS_FSB_TO_AGNO(mp,
					bma.cur->bc_private.b.firstblock)));
			*firstblock = bma.cur->bc_private.b.firstblock;
L
Linus Torvalds 已提交
4792
		}
4793 4794 4795 4796 4797 4798 4799 4800
		xfs_btree_del_cursor(bma.cur,
			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
	}
	if (!error)
		xfs_bmap_validate_ret(orig_bno, orig_len, orig_flags, orig_mval,
			orig_nmap, *nmap);
	return error;
}
4801

4802 4803 4804 4805 4806 4807 4808
/*
 * When a delalloc extent is split (e.g., due to a hole punch), the original
 * indlen reservation must be shared across the two new extents that are left
 * behind.
 *
 * Given the original reservation and the worst case indlen for the two new
 * extents (as calculated by xfs_bmap_worst_indlen()), split the original
4809 4810 4811 4812
 * reservation fairly across the two new extents. If necessary, steal available
 * blocks from a deleted extent to make up a reservation deficiency (e.g., if
 * ores == 1). The number of stolen blocks is returned. The availability and
 * subsequent accounting of stolen blocks is the responsibility of the caller.
4813
 */
4814
static xfs_filblks_t
4815 4816 4817
xfs_bmap_split_indlen(
	xfs_filblks_t			ores,		/* original res. */
	xfs_filblks_t			*indlen1,	/* ext1 worst indlen */
4818 4819
	xfs_filblks_t			*indlen2,	/* ext2 worst indlen */
	xfs_filblks_t			avail)		/* stealable blocks */
4820 4821 4822 4823
{
	xfs_filblks_t			len1 = *indlen1;
	xfs_filblks_t			len2 = *indlen2;
	xfs_filblks_t			nres = len1 + len2; /* new total res. */
4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834
	xfs_filblks_t			stolen = 0;

	/*
	 * Steal as many blocks as we can to try and satisfy the worst case
	 * indlen for both new extents.
	 */
	while (nres > ores && avail) {
		nres--;
		avail--;
		stolen++;
	}
4835 4836

	/*
4837 4838 4839 4840 4841
	 * The only blocks available are those reserved for the original
	 * extent and what we can steal from the extent being removed.
	 * If this still isn't enough to satisfy the combined
	 * requirements for the two new extents, skim blocks off of each
	 * of the new reservations until they match what is available.
4842 4843 4844 4845 4846 4847 4848 4849 4850 4851 4852 4853 4854 4855 4856 4857
	 */
	while (nres > ores) {
		if (len1) {
			len1--;
			nres--;
		}
		if (nres == ores)
			break;
		if (len2) {
			len2--;
			nres--;
		}
	}

	*indlen1 = len1;
	*indlen2 = len2;
4858 4859

	return stolen;
4860 4861
}

4862 4863 4864 4865 4866 4867 4868 4869 4870
/*
 * Called by xfs_bmapi to update file extent records and the btree
 * after removing space (or undoing a delayed allocation).
 */
STATIC int				/* error */
xfs_bmap_del_extent(
	xfs_inode_t		*ip,	/* incore inode pointer */
	xfs_trans_t		*tp,	/* current transaction pointer */
	xfs_extnum_t		*idx,	/* extent number to update/delete */
4871
	struct xfs_defer_ops	*dfops,	/* list of extents to be freed */
4872 4873 4874
	xfs_btree_cur_t		*cur,	/* if null, not a btree */
	xfs_bmbt_irec_t		*del,	/* data to remove from extents */
	int			*logflagsp, /* inode logging flags */
4875 4876
	int			whichfork, /* data or attr fork */
	int			bflags)	/* bmapi flags */
4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899
{
	xfs_filblks_t		da_new;	/* new delay-alloc indirect blocks */
	xfs_filblks_t		da_old;	/* old delay-alloc indirect blocks */
	xfs_fsblock_t		del_endblock=0;	/* first block past del */
	xfs_fileoff_t		del_endoff;	/* first offset past del */
	int			delay;	/* current block is delayed allocated */
	int			do_fx;	/* free extent at end of routine */
	xfs_bmbt_rec_host_t	*ep;	/* current extent entry pointer */
	int			error;	/* error return value */
	int			flags;	/* inode logging flags */
	xfs_bmbt_irec_t		got;	/* current extent entry */
	xfs_fileoff_t		got_endoff;	/* first offset past got */
	int			i;	/* temp state */
	xfs_ifork_t		*ifp;	/* inode fork pointer */
	xfs_mount_t		*mp;	/* mount structure */
	xfs_filblks_t		nblks;	/* quota/sb block count */
	xfs_bmbt_irec_t		new;	/* new record to be inserted */
	/* REFERENCED */
	uint			qfield;	/* quota field to update */
	xfs_filblks_t		temp;	/* for indirect length calculations */
	xfs_filblks_t		temp2;	/* for indirect length calculations */
	int			state = 0;

4900 4901
	mp = ip->i_mount;
	XFS_STATS_INC(mp, xs_del_exlist);
4902 4903 4904

	if (whichfork == XFS_ATTR_FORK)
		state |= BMAP_ATTRFORK;
D
Darrick J. Wong 已提交
4905 4906
	else if (whichfork == XFS_COW_FORK)
		state |= BMAP_COWFORK;
4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949

	ifp = XFS_IFORK_PTR(ip, whichfork);
	ASSERT((*idx >= 0) && (*idx < ifp->if_bytes /
		(uint)sizeof(xfs_bmbt_rec_t)));
	ASSERT(del->br_blockcount > 0);
	ep = xfs_iext_get_ext(ifp, *idx);
	xfs_bmbt_get_all(ep, &got);
	ASSERT(got.br_startoff <= del->br_startoff);
	del_endoff = del->br_startoff + del->br_blockcount;
	got_endoff = got.br_startoff + got.br_blockcount;
	ASSERT(got_endoff >= del_endoff);
	delay = isnullstartblock(got.br_startblock);
	ASSERT(isnullstartblock(del->br_startblock) == delay);
	flags = 0;
	qfield = 0;
	error = 0;
	/*
	 * If deleting a real allocation, must free up the disk space.
	 */
	if (!delay) {
		flags = XFS_ILOG_CORE;
		/*
		 * Realtime allocation.  Free it and record di_nblocks update.
		 */
		if (whichfork == XFS_DATA_FORK && XFS_IS_REALTIME_INODE(ip)) {
			xfs_fsblock_t	bno;
			xfs_filblks_t	len;

			ASSERT(do_mod(del->br_blockcount,
				      mp->m_sb.sb_rextsize) == 0);
			ASSERT(do_mod(del->br_startblock,
				      mp->m_sb.sb_rextsize) == 0);
			bno = del->br_startblock;
			len = del->br_blockcount;
			do_div(bno, mp->m_sb.sb_rextsize);
			do_div(len, mp->m_sb.sb_rextsize);
			error = xfs_rtfree_extent(tp, bno, (xfs_extlen_t)len);
			if (error)
				goto done;
			do_fx = 0;
			nblks = len * mp->m_sb.sb_rextsize;
			qfield = XFS_TRANS_DQ_RTBCOUNT;
		}
L
Linus Torvalds 已提交
4950
		/*
4951
		 * Ordinary allocation.
L
Linus Torvalds 已提交
4952
		 */
4953 4954 4955 4956
		else {
			do_fx = 1;
			nblks = del->br_blockcount;
			qfield = XFS_TRANS_DQ_BCOUNT;
L
Linus Torvalds 已提交
4957 4958
		}
		/*
4959
		 * Set up del_endblock and cur for later.
L
Linus Torvalds 已提交
4960
		 */
4961 4962 4963 4964 4965 4966
		del_endblock = del->br_startblock + del->br_blockcount;
		if (cur) {
			if ((error = xfs_bmbt_lookup_eq(cur, got.br_startoff,
					got.br_startblock, got.br_blockcount,
					&i)))
				goto done;
4967
			XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
L
Linus Torvalds 已提交
4968
		}
4969 4970 4971 4972 4973 4974
		da_old = da_new = 0;
	} else {
		da_old = startblockval(got.br_startblock);
		da_new = 0;
		nblks = 0;
		do_fx = 0;
L
Linus Torvalds 已提交
4975
	}
4976

L
Linus Torvalds 已提交
4977
	/*
4978 4979
	 * Set flag value to use in switch statement.
	 * Left-contig is 2, right-contig is 1.
L
Linus Torvalds 已提交
4980
	 */
4981 4982 4983 4984 4985 4986
	switch (((got.br_startoff == del->br_startoff) << 1) |
		(got_endoff == del_endoff)) {
	case 3:
		/*
		 * Matches the whole extent.  Delete the entry.
		 */
4987
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002
		xfs_iext_remove(ip, *idx, 1,
				whichfork == XFS_ATTR_FORK ? BMAP_ATTRFORK : 0);
		--*idx;
		if (delay)
			break;

		XFS_IFORK_NEXT_SET(ip, whichfork,
			XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
		flags |= XFS_ILOG_CORE;
		if (!cur) {
			flags |= xfs_ilog_fext(whichfork);
			break;
		}
		if ((error = xfs_btree_delete(cur, &i)))
			goto done;
5003
		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070 5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083 5084
		break;

	case 2:
		/*
		 * Deleting the first part of the extent.
		 */
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_startoff(ep, del_endoff);
		temp = got.br_blockcount - del->br_blockcount;
		xfs_bmbt_set_blockcount(ep, temp);
		if (delay) {
			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
				da_old);
			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
			trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
			da_new = temp;
			break;
		}
		xfs_bmbt_set_startblock(ep, del_endblock);
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
		if (!cur) {
			flags |= xfs_ilog_fext(whichfork);
			break;
		}
		if ((error = xfs_bmbt_update(cur, del_endoff, del_endblock,
				got.br_blockcount - del->br_blockcount,
				got.br_state)))
			goto done;
		break;

	case 1:
		/*
		 * Deleting the last part of the extent.
		 */
		temp = got.br_blockcount - del->br_blockcount;
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep, temp);
		if (delay) {
			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
				da_old);
			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
			trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
			da_new = temp;
			break;
		}
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
		if (!cur) {
			flags |= xfs_ilog_fext(whichfork);
			break;
		}
		if ((error = xfs_bmbt_update(cur, got.br_startoff,
				got.br_startblock,
				got.br_blockcount - del->br_blockcount,
				got.br_state)))
			goto done;
		break;

	case 0:
		/*
		 * Deleting the middle of the extent.
		 */
		temp = del->br_startoff - got.br_startoff;
		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep, temp);
		new.br_startoff = del_endoff;
		temp2 = got_endoff - del_endoff;
		new.br_blockcount = temp2;
		new.br_state = got.br_state;
		if (!delay) {
			new.br_startblock = del_endblock;
			flags |= XFS_ILOG_CORE;
			if (cur) {
				if ((error = xfs_bmbt_update(cur,
						got.br_startoff,
						got.br_startblock, temp,
						got.br_state)))
					goto done;
				if ((error = xfs_btree_increment(cur, 0, &i)))
					goto done;
				cur->bc_rec.b = new;
				error = xfs_btree_insert(cur, &i);
D
Dave Chinner 已提交
5085
				if (error && error != -ENOSPC)
5086 5087 5088 5089 5090 5091 5092
					goto done;
				/*
				 * If get no-space back from btree insert,
				 * it tried a split, and we have a zero
				 * block reservation.
				 * Fix up our state and return the error.
				 */
D
Dave Chinner 已提交
5093
				if (error == -ENOSPC) {
5094 5095 5096 5097 5098 5099 5100 5101 5102
					/*
					 * Reset the cursor, don't trust
					 * it after any insert operation.
					 */
					if ((error = xfs_bmbt_lookup_eq(cur,
							got.br_startoff,
							got.br_startblock,
							temp, &i)))
						goto done;
5103 5104
					XFS_WANT_CORRUPTED_GOTO(mp,
								i == 1, done);
5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121
					/*
					 * Update the btree record back
					 * to the original value.
					 */
					if ((error = xfs_bmbt_update(cur,
							got.br_startoff,
							got.br_startblock,
							got.br_blockcount,
							got.br_state)))
						goto done;
					/*
					 * Reset the extent record back
					 * to the original value.
					 */
					xfs_bmbt_set_blockcount(ep,
						got.br_blockcount);
					flags = 0;
D
Dave Chinner 已提交
5122
					error = -ENOSPC;
5123 5124
					goto done;
				}
5125
				XFS_WANT_CORRUPTED_GOTO(mp, i == 1, done);
5126 5127 5128 5129 5130
			} else
				flags |= xfs_ilog_fext(whichfork);
			XFS_IFORK_NEXT_SET(ip, whichfork,
				XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
		} else {
5131
			xfs_filblks_t	stolen;
5132
			ASSERT(whichfork == XFS_DATA_FORK);
5133 5134 5135

			/*
			 * Distribute the original indlen reservation across the
5136 5137 5138
			 * two new extents. Steal blocks from the deleted extent
			 * if necessary. Stealing blocks simply fudges the
			 * fdblocks accounting in xfs_bunmapi().
5139 5140 5141
			 */
			temp = xfs_bmap_worst_indlen(ip, got.br_blockcount);
			temp2 = xfs_bmap_worst_indlen(ip, new.br_blockcount);
5142 5143 5144 5145
			stolen = xfs_bmap_split_indlen(da_old, &temp, &temp2,
						       del->br_blockcount);
			da_new = temp + temp2 - stolen;
			del->br_blockcount -= stolen;
5146 5147

			/*
5148 5149
			 * Set the reservation for each extent. Warn if either
			 * is zero as this can lead to delalloc problems.
5150
			 */
5151
			WARN_ON_ONCE(!temp || !temp2);
5152 5153 5154 5155 5156 5157 5158
			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
			new.br_startblock = nullstartblock((int)temp2);
		}
		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
		xfs_iext_insert(ip, *idx + 1, 1, &new, state);
		++*idx;
		break;
L
Linus Torvalds 已提交
5159
	}
5160 5161 5162 5163 5164 5165 5166 5167

	/* remove reverse mapping */
	if (!delay) {
		error = xfs_rmap_unmap_extent(mp, dfops, ip, whichfork, del);
		if (error)
			goto done;
	}

L
Linus Torvalds 已提交
5168
	/*
5169
	 * If we need to, add to list of extents to delete.
L
Linus Torvalds 已提交
5170
	 */
5171
	if (do_fx && !(bflags & XFS_BMAPI_REMAP)) {
5172 5173 5174 5175 5176 5177 5178 5179 5180
		if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) {
			error = xfs_refcount_decrease_extent(mp, dfops, del);
			if (error)
				goto done;
		} else
			xfs_bmap_add_free(mp, dfops, del->br_startblock,
					del->br_blockcount, NULL);
	}

L
Linus Torvalds 已提交
5181
	/*
5182
	 * Adjust inode # blocks in the file.
L
Linus Torvalds 已提交
5183
	 */
5184 5185
	if (nblks)
		ip->i_d.di_nblocks -= nblks;
L
Linus Torvalds 已提交
5186
	/*
5187
	 * Adjust quota data.
L
Linus Torvalds 已提交
5188
	 */
5189
	if (qfield && !(bflags & XFS_BMAPI_REMAP))
5190 5191 5192 5193 5194 5195 5196
		xfs_trans_mod_dquot_byino(tp, ip, qfield, (long)-nblks);

	/*
	 * Account for change in delayed indirect blocks.
	 * Nothing to do for disk quota accounting here.
	 */
	ASSERT(da_old >= da_new);
5197 5198
	if (da_old > da_new)
		xfs_mod_fdblocks(mp, (int64_t)(da_old - da_new), false);
5199 5200
done:
	*logflagsp = flags;
L
Linus Torvalds 已提交
5201 5202 5203
	return error;
}

5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235 5236
/* Remove an extent from the CoW fork.  Similar to xfs_bmap_del_extent. */
int
xfs_bunmapi_cow(
	struct xfs_inode		*ip,
	struct xfs_bmbt_irec		*del)
{
	xfs_filblks_t			da_new;
	xfs_filblks_t			da_old;
	xfs_fsblock_t			del_endblock = 0;
	xfs_fileoff_t			del_endoff;
	int				delay;
	struct xfs_bmbt_rec_host	*ep;
	int				error;
	struct xfs_bmbt_irec		got;
	xfs_fileoff_t			got_endoff;
	struct xfs_ifork		*ifp;
	struct xfs_mount		*mp;
	xfs_filblks_t			nblks;
	struct xfs_bmbt_irec		new;
	/* REFERENCED */
	uint				qfield;
	xfs_filblks_t			temp;
	xfs_filblks_t			temp2;
	int				state = BMAP_COWFORK;
	int				eof;
	xfs_extnum_t			eidx;

	mp = ip->i_mount;
	XFS_STATS_INC(mp, xs_del_exlist);

	ep = xfs_bmap_search_extents(ip, del->br_startoff, XFS_COW_FORK, &eof,
			&eidx, &got, &new);

5237
	ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
5238 5239 5240 5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372
	ASSERT((eidx >= 0) && (eidx < ifp->if_bytes /
		(uint)sizeof(xfs_bmbt_rec_t)));
	ASSERT(del->br_blockcount > 0);
	ASSERT(got.br_startoff <= del->br_startoff);
	del_endoff = del->br_startoff + del->br_blockcount;
	got_endoff = got.br_startoff + got.br_blockcount;
	ASSERT(got_endoff >= del_endoff);
	delay = isnullstartblock(got.br_startblock);
	ASSERT(isnullstartblock(del->br_startblock) == delay);
	qfield = 0;
	error = 0;
	/*
	 * If deleting a real allocation, must free up the disk space.
	 */
	if (!delay) {
		nblks = del->br_blockcount;
		qfield = XFS_TRANS_DQ_BCOUNT;
		/*
		 * Set up del_endblock and cur for later.
		 */
		del_endblock = del->br_startblock + del->br_blockcount;
		da_old = da_new = 0;
	} else {
		da_old = startblockval(got.br_startblock);
		da_new = 0;
		nblks = 0;
	}
	qfield = qfield;
	nblks = nblks;

	/*
	 * Set flag value to use in switch statement.
	 * Left-contig is 2, right-contig is 1.
	 */
	switch (((got.br_startoff == del->br_startoff) << 1) |
		(got_endoff == del_endoff)) {
	case 3:
		/*
		 * Matches the whole extent.  Delete the entry.
		 */
		xfs_iext_remove(ip, eidx, 1, BMAP_COWFORK);
		--eidx;
		break;

	case 2:
		/*
		 * Deleting the first part of the extent.
		 */
		trace_xfs_bmap_pre_update(ip, eidx, state, _THIS_IP_);
		xfs_bmbt_set_startoff(ep, del_endoff);
		temp = got.br_blockcount - del->br_blockcount;
		xfs_bmbt_set_blockcount(ep, temp);
		if (delay) {
			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
				da_old);
			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
			trace_xfs_bmap_post_update(ip, eidx, state, _THIS_IP_);
			da_new = temp;
			break;
		}
		xfs_bmbt_set_startblock(ep, del_endblock);
		trace_xfs_bmap_post_update(ip, eidx, state, _THIS_IP_);
		break;

	case 1:
		/*
		 * Deleting the last part of the extent.
		 */
		temp = got.br_blockcount - del->br_blockcount;
		trace_xfs_bmap_pre_update(ip, eidx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep, temp);
		if (delay) {
			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
				da_old);
			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
			trace_xfs_bmap_post_update(ip, eidx, state, _THIS_IP_);
			da_new = temp;
			break;
		}
		trace_xfs_bmap_post_update(ip, eidx, state, _THIS_IP_);
		break;

	case 0:
		/*
		 * Deleting the middle of the extent.
		 */
		temp = del->br_startoff - got.br_startoff;
		trace_xfs_bmap_pre_update(ip, eidx, state, _THIS_IP_);
		xfs_bmbt_set_blockcount(ep, temp);
		new.br_startoff = del_endoff;
		temp2 = got_endoff - del_endoff;
		new.br_blockcount = temp2;
		new.br_state = got.br_state;
		if (!delay) {
			new.br_startblock = del_endblock;
		} else {
			temp = xfs_bmap_worst_indlen(ip, temp);
			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
			temp2 = xfs_bmap_worst_indlen(ip, temp2);
			new.br_startblock = nullstartblock((int)temp2);
			da_new = temp + temp2;
			while (da_new > da_old) {
				if (temp) {
					temp--;
					da_new--;
					xfs_bmbt_set_startblock(ep,
						nullstartblock((int)temp));
				}
				if (da_new == da_old)
					break;
				if (temp2) {
					temp2--;
					da_new--;
					new.br_startblock =
						nullstartblock((int)temp2);
				}
			}
		}
		trace_xfs_bmap_post_update(ip, eidx, state, _THIS_IP_);
		xfs_iext_insert(ip, eidx + 1, 1, &new, state);
		++eidx;
		break;
	}

	/*
	 * Account for change in delayed indirect blocks.
	 * Nothing to do for disk quota accounting here.
	 */
	ASSERT(da_old >= da_new);
	if (da_old > da_new)
		xfs_mod_fdblocks(mp, (int64_t)(da_old - da_new), false);

	return error;
}

5373
/*
5374 5375 5376 5377
 * Unmap (remove) blocks from a file.
 * If nexts is nonzero then the number of extents to remove is limited to
 * that value.  If not all extents in the block range can be removed then
 * *done is set.
5378
 */
5379
int						/* error */
5380
__xfs_bunmapi(
5381 5382 5383
	xfs_trans_t		*tp,		/* transaction pointer */
	struct xfs_inode	*ip,		/* incore inode */
	xfs_fileoff_t		bno,		/* starting offset to unmap */
5384
	xfs_filblks_t		*rlen,		/* i/o: amount remaining */
5385 5386 5387 5388
	int			flags,		/* misc flags */
	xfs_extnum_t		nexts,		/* number of extents max */
	xfs_fsblock_t		*firstblock,	/* first allocated block
						   controls a.g. for allocs */
5389
	struct xfs_defer_ops	*dfops)		/* i/o: deferred updates */
5390
{
5391 5392 5393 5394 5395 5396 5397
	xfs_btree_cur_t		*cur;		/* bmap btree cursor */
	xfs_bmbt_irec_t		del;		/* extent being deleted */
	int			eof;		/* is deleting at eof */
	xfs_bmbt_rec_host_t	*ep;		/* extent record pointer */
	int			error;		/* error return value */
	xfs_extnum_t		extno;		/* extent number in list */
	xfs_bmbt_irec_t		got;		/* current extent record */
E
Eric Sandeen 已提交
5398
	xfs_ifork_t		*ifp;		/* inode fork pointer */
5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410
	int			isrt;		/* freeing in rt area */
	xfs_extnum_t		lastx;		/* last extent index used */
	int			logflags;	/* transaction logging flags */
	xfs_extlen_t		mod;		/* rt extent offset */
	xfs_mount_t		*mp;		/* mount structure */
	xfs_extnum_t		nextents;	/* number of file extents */
	xfs_bmbt_irec_t		prev;		/* previous extent record */
	xfs_fileoff_t		start;		/* first file offset deleted */
	int			tmp_logflags;	/* partial logging flags */
	int			wasdel;		/* was a delayed alloc extent */
	int			whichfork;	/* data or attribute fork */
	xfs_fsblock_t		sum;
5411
	xfs_filblks_t		len = *rlen;	/* length to unmap in file */
L
Linus Torvalds 已提交
5412

5413
	trace_xfs_bunmap(ip, bno, len, flags, _RET_IP_);
L
Linus Torvalds 已提交
5414

D
Darrick J. Wong 已提交
5415 5416
	whichfork = xfs_bmapi_whichfork(flags);
	ASSERT(whichfork != XFS_COW_FORK);
5417 5418 5419 5420 5421 5422
	ifp = XFS_IFORK_PTR(ip, whichfork);
	if (unlikely(
	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
		XFS_ERROR_REPORT("xfs_bunmapi", XFS_ERRLEVEL_LOW,
				 ip->i_mount);
D
Dave Chinner 已提交
5423
		return -EFSCORRUPTED;
L
Linus Torvalds 已提交
5424
	}
5425 5426
	mp = ip->i_mount;
	if (XFS_FORCED_SHUTDOWN(mp))
D
Dave Chinner 已提交
5427
		return -EIO;
L
Linus Torvalds 已提交
5428

5429
	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5430 5431
	ASSERT(len > 0);
	ASSERT(nexts >= 0);
L
Linus Torvalds 已提交
5432

5433 5434 5435 5436 5437
	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
	    (error = xfs_iread_extents(tp, ip, whichfork)))
		return error;
	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
	if (nextents == 0) {
5438
		*rlen = 0;
5439 5440
		return 0;
	}
5441
	XFS_STATS_INC(mp, xs_blk_unmap);
5442 5443 5444 5445 5446
	isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
	start = bno;
	bno = start + len - 1;
	ep = xfs_bmap_search_extents(ip, bno, whichfork, &eof, &lastx, &got,
		&prev);
L
Linus Torvalds 已提交
5447

5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461
	/*
	 * Check to see if the given block number is past the end of the
	 * file, back up to the last block if so...
	 */
	if (eof) {
		ep = xfs_iext_get_ext(ifp, --lastx);
		xfs_bmbt_get_all(ep, &got);
		bno = got.br_startoff + got.br_blockcount - 1;
	}
	logflags = 0;
	if (ifp->if_flags & XFS_IFBROOT) {
		ASSERT(XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_BTREE);
		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
		cur->bc_private.b.firstblock = *firstblock;
5462
		cur->bc_private.b.dfops = dfops;
5463 5464 5465 5466 5467 5468 5469 5470
		cur->bc_private.b.flags = 0;
	} else
		cur = NULL;

	if (isrt) {
		/*
		 * Synchronize by locking the bitmap inode.
		 */
5471
		xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
5472
		xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
5473 5474
		xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
		xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
5475
	}
5476

5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513 5514 5515
	extno = 0;
	while (bno != (xfs_fileoff_t)-1 && bno >= start && lastx >= 0 &&
	       (nexts == 0 || extno < nexts)) {
		/*
		 * Is the found extent after a hole in which bno lives?
		 * Just back up to the previous extent, if so.
		 */
		if (got.br_startoff > bno) {
			if (--lastx < 0)
				break;
			ep = xfs_iext_get_ext(ifp, lastx);
			xfs_bmbt_get_all(ep, &got);
		}
		/*
		 * Is the last block of this extent before the range
		 * we're supposed to delete?  If so, we're done.
		 */
		bno = XFS_FILEOFF_MIN(bno,
			got.br_startoff + got.br_blockcount - 1);
		if (bno < start)
			break;
		/*
		 * Then deal with the (possibly delayed) allocated space
		 * we found.
		 */
		ASSERT(ep != NULL);
		del = got;
		wasdel = isnullstartblock(del.br_startblock);
		if (got.br_startoff < start) {
			del.br_startoff = start;
			del.br_blockcount -= start - got.br_startoff;
			if (!wasdel)
				del.br_startblock += start - got.br_startoff;
		}
		if (del.br_startoff + del.br_blockcount > bno + 1)
			del.br_blockcount = bno + 1 - del.br_startoff;
		sum = del.br_startblock + del.br_blockcount;
		if (isrt &&
		    (mod = do_mod(sum, mp->m_sb.sb_rextsize))) {
5516
			/*
5517 5518 5519 5520 5521
			 * Realtime extent not lined up at the end.
			 * The extent could have been split into written
			 * and unwritten pieces, or we could just be
			 * unmapping part of it.  But we can't really
			 * get rid of part of a realtime extent.
5522
			 */
5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537
			if (del.br_state == XFS_EXT_UNWRITTEN ||
			    !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
				/*
				 * This piece is unwritten, or we're not
				 * using unwritten extents.  Skip over it.
				 */
				ASSERT(bno >= mod);
				bno -= mod > del.br_blockcount ?
					del.br_blockcount : mod;
				if (bno < got.br_startoff) {
					if (--lastx >= 0)
						xfs_bmbt_get_all(xfs_iext_get_ext(
							ifp, lastx), &got);
				}
				continue;
L
Linus Torvalds 已提交
5538
			}
T
Tao Ma 已提交
5539
			/*
5540 5541
			 * It's written, turn it unwritten.
			 * This is better than zeroing it.
T
Tao Ma 已提交
5542
			 */
5543
			ASSERT(del.br_state == XFS_EXT_NORM);
5544
			ASSERT(tp->t_blk_res > 0);
5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555
			/*
			 * If this spans a realtime extent boundary,
			 * chop it back to the start of the one we end at.
			 */
			if (del.br_blockcount > mod) {
				del.br_startoff += del.br_blockcount - mod;
				del.br_startblock += del.br_blockcount - mod;
				del.br_blockcount = mod;
			}
			del.br_state = XFS_EXT_UNWRITTEN;
			error = xfs_bmap_add_extent_unwritten_real(tp, ip,
5556
					&lastx, &cur, &del, firstblock, dfops,
5557 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574
					&logflags);
			if (error)
				goto error0;
			goto nodelete;
		}
		if (isrt && (mod = do_mod(del.br_startblock, mp->m_sb.sb_rextsize))) {
			/*
			 * Realtime extent is lined up at the end but not
			 * at the front.  We'll get rid of full extents if
			 * we can.
			 */
			mod = mp->m_sb.sb_rextsize - mod;
			if (del.br_blockcount > mod) {
				del.br_blockcount -= mod;
				del.br_startoff += mod;
				del.br_startblock += mod;
			} else if ((del.br_startoff == start &&
				    (del.br_state == XFS_EXT_UNWRITTEN ||
5575
				     tp->t_blk_res == 0)) ||
5576 5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589
				   !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
				/*
				 * Can't make it unwritten.  There isn't
				 * a full extent here so just skip it.
				 */
				ASSERT(bno >= del.br_blockcount);
				bno -= del.br_blockcount;
				if (got.br_startoff > bno) {
					if (--lastx >= 0) {
						ep = xfs_iext_get_ext(ifp,
								      lastx);
						xfs_bmbt_get_all(ep, &got);
					}
				}
T
Tao Ma 已提交
5590
				continue;
5591 5592 5593 5594 5595 5596 5597 5598 5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611 5612 5613 5614
			} else if (del.br_state == XFS_EXT_UNWRITTEN) {
				/*
				 * This one is already unwritten.
				 * It must have a written left neighbor.
				 * Unwrite the killed part of that one and
				 * try again.
				 */
				ASSERT(lastx > 0);
				xfs_bmbt_get_all(xfs_iext_get_ext(ifp,
						lastx - 1), &prev);
				ASSERT(prev.br_state == XFS_EXT_NORM);
				ASSERT(!isnullstartblock(prev.br_startblock));
				ASSERT(del.br_startblock ==
				       prev.br_startblock + prev.br_blockcount);
				if (prev.br_startoff < start) {
					mod = start - prev.br_startoff;
					prev.br_blockcount -= mod;
					prev.br_startblock += mod;
					prev.br_startoff = start;
				}
				prev.br_state = XFS_EXT_UNWRITTEN;
				lastx--;
				error = xfs_bmap_add_extent_unwritten_real(tp,
						ip, &lastx, &cur, &prev,
5615
						firstblock, dfops, &logflags);
5616 5617 5618 5619 5620 5621 5622 5623
				if (error)
					goto error0;
				goto nodelete;
			} else {
				ASSERT(del.br_state == XFS_EXT_NORM);
				del.br_state = XFS_EXT_UNWRITTEN;
				error = xfs_bmap_add_extent_unwritten_real(tp,
						ip, &lastx, &cur, &del,
5624
						firstblock, dfops, &logflags);
5625 5626 5627
				if (error)
					goto error0;
				goto nodelete;
T
Tao Ma 已提交
5628
			}
L
Linus Torvalds 已提交
5629 5630
		}

5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641
		/*
		 * If it's the case where the directory code is running
		 * with no block reservation, and the deleted block is in
		 * the middle of its extent, and the resulting insert
		 * of an extent would cause transformation to btree format,
		 * then reject it.  The calling code will then swap
		 * blocks around instead.
		 * We have to do this now, rather than waiting for the
		 * conversion to btree format, since the transaction
		 * will be dirty.
		 */
5642
		if (!wasdel && tp->t_blk_res == 0 &&
5643 5644 5645 5646 5647 5648
		    XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS &&
		    XFS_IFORK_NEXTENTS(ip, whichfork) >= /* Note the >= */
			XFS_IFORK_MAXEXT(ip, whichfork) &&
		    del.br_startoff > got.br_startoff &&
		    del.br_startoff + del.br_blockcount <
		    got.br_startoff + got.br_blockcount) {
D
Dave Chinner 已提交
5649
			error = -ENOSPC;
5650
			goto error0;
L
Linus Torvalds 已提交
5651
		}
5652 5653 5654 5655 5656 5657 5658 5659 5660 5661 5662 5663 5664 5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681

		/*
		 * Unreserve quota and update realtime free space, if
		 * appropriate. If delayed allocation, update the inode delalloc
		 * counter now and wait to update the sb counters as
		 * xfs_bmap_del_extent() might need to borrow some blocks.
		 */
		if (wasdel) {
			ASSERT(startblockval(del.br_startblock) > 0);
			if (isrt) {
				xfs_filblks_t rtexts;

				rtexts = XFS_FSB_TO_B(mp, del.br_blockcount);
				do_div(rtexts, mp->m_sb.sb_rextsize);
				xfs_mod_frextents(mp, (int64_t)rtexts);
				(void)xfs_trans_reserve_quota_nblks(NULL,
					ip, -((long)del.br_blockcount), 0,
					XFS_QMOPT_RES_RTBLKS);
			} else {
				(void)xfs_trans_reserve_quota_nblks(NULL,
					ip, -((long)del.br_blockcount), 0,
					XFS_QMOPT_RES_REGBLKS);
			}
			ip->i_delayed_blks -= del.br_blockcount;
			if (cur)
				cur->bc_private.b.flags |=
					XFS_BTCUR_BPRV_WASDEL;
		} else if (cur)
			cur->bc_private.b.flags &= ~XFS_BTCUR_BPRV_WASDEL;

5682
		error = xfs_bmap_del_extent(ip, tp, &lastx, dfops, cur, &del,
5683
				&tmp_logflags, whichfork, flags);
5684 5685 5686
		logflags |= tmp_logflags;
		if (error)
			goto error0;
5687 5688 5689 5690

		if (!isrt && wasdel)
			xfs_mod_fdblocks(mp, (int64_t)del.br_blockcount, false);

5691 5692
		bno = del.br_startoff - 1;
nodelete:
L
Linus Torvalds 已提交
5693
		/*
5694
		 * If not done go on to the next (previous) record.
L
Linus Torvalds 已提交
5695
		 */
5696 5697 5698 5699 5700 5701 5702 5703 5704
		if (bno != (xfs_fileoff_t)-1 && bno >= start) {
			if (lastx >= 0) {
				ep = xfs_iext_get_ext(ifp, lastx);
				if (xfs_bmbt_get_startoff(ep) > bno) {
					if (--lastx >= 0)
						ep = xfs_iext_get_ext(ifp,
								      lastx);
				}
				xfs_bmbt_get_all(ep, &got);
L
Linus Torvalds 已提交
5705
			}
5706
			extno++;
L
Linus Torvalds 已提交
5707 5708
		}
	}
5709 5710 5711 5712
	if (bno == (xfs_fileoff_t)-1 || bno < start || lastx < 0)
		*rlen = 0;
	else
		*rlen = bno - start + 1;
5713

L
Linus Torvalds 已提交
5714
	/*
5715
	 * Convert to a btree if necessary.
L
Linus Torvalds 已提交
5716
	 */
5717 5718
	if (xfs_bmap_needs_btree(ip, whichfork)) {
		ASSERT(cur == NULL);
5719
		error = xfs_bmap_extents_to_btree(tp, ip, firstblock, dfops,
5720 5721 5722 5723
			&cur, 0, &tmp_logflags, whichfork);
		logflags |= tmp_logflags;
		if (error)
			goto error0;
L
Linus Torvalds 已提交
5724 5725
	}
	/*
5726
	 * transform from btree to extents, give it cur
L
Linus Torvalds 已提交
5727
	 */
5728 5729 5730 5731 5732 5733 5734 5735
	else if (xfs_bmap_wants_extents(ip, whichfork)) {
		ASSERT(cur != NULL);
		error = xfs_bmap_btree_to_extents(tp, ip, cur, &tmp_logflags,
			whichfork);
		logflags |= tmp_logflags;
		if (error)
			goto error0;
	}
L
Linus Torvalds 已提交
5736
	/*
5737
	 * transform from extents to local?
L
Linus Torvalds 已提交
5738
	 */
5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750 5751 5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766
	error = 0;
error0:
	/*
	 * Log everything.  Do this after conversion, there's no point in
	 * logging the extent records if we've converted to btree format.
	 */
	if ((logflags & xfs_ilog_fext(whichfork)) &&
	    XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS)
		logflags &= ~xfs_ilog_fext(whichfork);
	else if ((logflags & xfs_ilog_fbroot(whichfork)) &&
		 XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)
		logflags &= ~xfs_ilog_fbroot(whichfork);
	/*
	 * Log inode even in the error case, if the transaction
	 * is dirty we'll need to shut down the filesystem.
	 */
	if (logflags)
		xfs_trans_log_inode(tp, ip, logflags);
	if (cur) {
		if (!error) {
			*firstblock = cur->bc_private.b.firstblock;
			cur->bc_private.b.allocated = 0;
		}
		xfs_btree_del_cursor(cur,
			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
	}
	return error;
}
5767

5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785 5786 5787 5788
/* Unmap a range of a file. */
int
xfs_bunmapi(
	xfs_trans_t		*tp,
	struct xfs_inode	*ip,
	xfs_fileoff_t		bno,
	xfs_filblks_t		len,
	int			flags,
	xfs_extnum_t		nexts,
	xfs_fsblock_t		*firstblock,
	struct xfs_defer_ops	*dfops,
	int			*done)
{
	int			error;

	error = __xfs_bunmapi(tp, ip, bno, &len, flags, nexts, firstblock,
			dfops);
	*done = (len == 0);
	return error;
}

5789 5790 5791 5792 5793 5794 5795 5796 5797 5798 5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839
/*
 * Determine whether an extent shift can be accomplished by a merge with the
 * extent that precedes the target hole of the shift.
 */
STATIC bool
xfs_bmse_can_merge(
	struct xfs_bmbt_irec	*left,	/* preceding extent */
	struct xfs_bmbt_irec	*got,	/* current extent to shift */
	xfs_fileoff_t		shift)	/* shift fsb */
{
	xfs_fileoff_t		startoff;

	startoff = got->br_startoff - shift;

	/*
	 * The extent, once shifted, must be adjacent in-file and on-disk with
	 * the preceding extent.
	 */
	if ((left->br_startoff + left->br_blockcount != startoff) ||
	    (left->br_startblock + left->br_blockcount != got->br_startblock) ||
	    (left->br_state != got->br_state) ||
	    (left->br_blockcount + got->br_blockcount > MAXEXTLEN))
		return false;

	return true;
}

/*
 * A bmap extent shift adjusts the file offset of an extent to fill a preceding
 * hole in the file. If an extent shift would result in the extent being fully
 * adjacent to the extent that currently precedes the hole, we can merge with
 * the preceding extent rather than do the shift.
 *
 * This function assumes the caller has verified a shift-by-merge is possible
 * with the provided extents via xfs_bmse_can_merge().
 */
STATIC int
xfs_bmse_merge(
	struct xfs_inode		*ip,
	int				whichfork,
	xfs_fileoff_t			shift,		/* shift fsb */
	int				current_ext,	/* idx of gotp */
	struct xfs_bmbt_rec_host	*gotp,		/* extent to shift */
	struct xfs_bmbt_rec_host	*leftp,		/* preceding extent */
	struct xfs_btree_cur		*cur,
	int				*logflags)	/* output */
{
	struct xfs_bmbt_irec		got;
	struct xfs_bmbt_irec		left;
	xfs_filblks_t			blockcount;
	int				error, i;
5840
	struct xfs_mount		*mp = ip->i_mount;
5841 5842 5843 5844 5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866 5867 5868 5869 5870 5871 5872 5873

	xfs_bmbt_get_all(gotp, &got);
	xfs_bmbt_get_all(leftp, &left);
	blockcount = left.br_blockcount + got.br_blockcount;

	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
	ASSERT(xfs_bmse_can_merge(&left, &got, shift));

	/*
	 * Merge the in-core extents. Note that the host record pointers and
	 * current_ext index are invalid once the extent has been removed via
	 * xfs_iext_remove().
	 */
	xfs_bmbt_set_blockcount(leftp, blockcount);
	xfs_iext_remove(ip, current_ext, 1, 0);

	/*
	 * Update the on-disk extent count, the btree if necessary and log the
	 * inode.
	 */
	XFS_IFORK_NEXT_SET(ip, whichfork,
			   XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
	*logflags |= XFS_ILOG_CORE;
	if (!cur) {
		*logflags |= XFS_ILOG_DEXT;
		return 0;
	}

	/* lookup and remove the extent to merge */
	error = xfs_bmbt_lookup_eq(cur, got.br_startoff, got.br_startblock,
				   got.br_blockcount, &i);
	if (error)
D
Dave Chinner 已提交
5874
		return error;
5875
	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5876 5877 5878

	error = xfs_btree_delete(cur, &i);
	if (error)
D
Dave Chinner 已提交
5879
		return error;
5880
	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5881 5882 5883 5884 5885

	/* lookup and update size of the previous extent */
	error = xfs_bmbt_lookup_eq(cur, left.br_startoff, left.br_startblock,
				   left.br_blockcount, &i);
	if (error)
D
Dave Chinner 已提交
5886
		return error;
5887
	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
5888 5889 5890

	left.br_blockcount = blockcount;

D
Dave Chinner 已提交
5891 5892
	return xfs_bmbt_update(cur, left.br_startoff, left.br_startblock,
			       left.br_blockcount, left.br_state);
5893 5894
}

5895 5896 5897 5898 5899 5900 5901 5902 5903 5904 5905
/*
 * Shift a single extent.
 */
STATIC int
xfs_bmse_shift_one(
	struct xfs_inode		*ip,
	int				whichfork,
	xfs_fileoff_t			offset_shift_fsb,
	int				*current_ext,
	struct xfs_bmbt_rec_host	*gotp,
	struct xfs_btree_cur		*cur,
5906
	int				*logflags,
5907 5908
	enum shift_direction		direction,
	struct xfs_defer_ops		*dfops)
5909 5910
{
	struct xfs_ifork		*ifp;
5911
	struct xfs_mount		*mp;
5912
	xfs_fileoff_t			startoff;
5913
	struct xfs_bmbt_rec_host	*adj_irecp;
5914
	struct xfs_bmbt_irec		got;
5915
	struct xfs_bmbt_irec		adj_irec;
5916 5917
	int				error;
	int				i;
5918
	int				total_extents;
5919

5920
	mp = ip->i_mount;
5921
	ifp = XFS_IFORK_PTR(ip, whichfork);
5922
	total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
5923 5924 5925

	xfs_bmbt_get_all(gotp, &got);

5926
	/* delalloc extents should be prevented by caller */
5927
	XFS_WANT_CORRUPTED_RETURN(mp, !isnullstartblock(got.br_startblock));
5928

5929 5930 5931 5932 5933 5934 5935 5936 5937 5938 5939 5940 5941 5942 5943 5944 5945 5946 5947
	if (direction == SHIFT_LEFT) {
		startoff = got.br_startoff - offset_shift_fsb;

		/*
		 * Check for merge if we've got an extent to the left,
		 * otherwise make sure there's enough room at the start
		 * of the file for the shift.
		 */
		if (!*current_ext) {
			if (got.br_startoff < offset_shift_fsb)
				return -EINVAL;
			goto update_current_ext;
		}
		/*
		 * grab the left extent and check for a large
		 * enough hole.
		 */
		adj_irecp = xfs_iext_get_ext(ifp, *current_ext - 1);
		xfs_bmbt_get_all(adj_irecp, &adj_irec);
5948

5949 5950
		if (startoff <
		    adj_irec.br_startoff + adj_irec.br_blockcount)
5951
			return -EINVAL;
5952

5953
		/* check whether to merge the extent or shift it down */
5954 5955
		if (xfs_bmse_can_merge(&adj_irec, &got,
				       offset_shift_fsb)) {
5956 5957 5958 5959 5960 5961 5962
			error = xfs_bmse_merge(ip, whichfork, offset_shift_fsb,
					       *current_ext, gotp, adj_irecp,
					       cur, logflags);
			if (error)
				return error;
			adj_irec = got;
			goto update_rmap;
5963
		}
5964 5965 5966 5967 5968 5969 5970 5971 5972 5973 5974 5975 5976 5977 5978 5979 5980 5981 5982 5983 5984 5985 5986 5987
	} else {
		startoff = got.br_startoff + offset_shift_fsb;
		/* nothing to move if this is the last extent */
		if (*current_ext >= (total_extents - 1))
			goto update_current_ext;
		/*
		 * If this is not the last extent in the file, make sure there
		 * is enough room between current extent and next extent for
		 * accommodating the shift.
		 */
		adj_irecp = xfs_iext_get_ext(ifp, *current_ext + 1);
		xfs_bmbt_get_all(adj_irecp, &adj_irec);
		if (startoff + got.br_blockcount > adj_irec.br_startoff)
			return -EINVAL;
		/*
		 * Unlike a left shift (which involves a hole punch),
		 * a right shift does not modify extent neighbors
		 * in any way. We should never find mergeable extents
		 * in this scenario. Check anyways and warn if we
		 * encounter two extents that could be one.
		 */
		if (xfs_bmse_can_merge(&got, &adj_irec, offset_shift_fsb))
			WARN_ON_ONCE(1);
	}
5988 5989 5990 5991
	/*
	 * Increment the extent index for the next iteration, update the start
	 * offset of the in-core extent and update the btree if applicable.
	 */
5992 5993 5994 5995 5996
update_current_ext:
	if (direction == SHIFT_LEFT)
		(*current_ext)++;
	else
		(*current_ext)--;
5997 5998
	xfs_bmbt_set_startoff(gotp, startoff);
	*logflags |= XFS_ILOG_CORE;
5999
	adj_irec = got;
6000 6001
	if (!cur) {
		*logflags |= XFS_ILOG_DEXT;
6002
		goto update_rmap;
6003 6004 6005 6006 6007 6008
	}

	error = xfs_bmbt_lookup_eq(cur, got.br_startoff, got.br_startblock,
				   got.br_blockcount, &i);
	if (error)
		return error;
6009
	XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
6010 6011

	got.br_startoff = startoff;
6012 6013 6014 6015 6016 6017 6018 6019 6020 6021 6022 6023
	error = xfs_bmbt_update(cur, got.br_startoff, got.br_startblock,
			got.br_blockcount, got.br_state);
	if (error)
		return error;

update_rmap:
	/* update reverse mapping */
	error = xfs_rmap_unmap_extent(mp, dfops, ip, whichfork, &adj_irec);
	if (error)
		return error;
	adj_irec.br_startoff = startoff;
	return xfs_rmap_map_extent(mp, dfops, ip, whichfork, &adj_irec);
6024 6025
}

6026
/*
6027
 * Shift extent records to the left/right to cover/create a hole.
6028
 *
6029
 * The maximum number of extents to be shifted in a single operation is
6030
 * @num_exts. @stop_fsb specifies the file offset at which to stop shift and the
6031 6032 6033 6034
 * file offset where we've left off is returned in @next_fsb. @offset_shift_fsb
 * is the length by which each extent is shifted. If there is no hole to shift
 * the extents into, this will be considered invalid operation and we abort
 * immediately.
6035 6036 6037 6038 6039
 */
int
xfs_bmap_shift_extents(
	struct xfs_trans	*tp,
	struct xfs_inode	*ip,
6040
	xfs_fileoff_t		*next_fsb,
6041
	xfs_fileoff_t		offset_shift_fsb,
6042
	int			*done,
6043
	xfs_fileoff_t		stop_fsb,
6044
	xfs_fsblock_t		*firstblock,
6045
	struct xfs_defer_ops	*dfops,
6046
	enum shift_direction	direction,
6047 6048
	int			num_exts)
{
6049
	struct xfs_btree_cur		*cur = NULL;
6050 6051 6052 6053 6054
	struct xfs_bmbt_rec_host	*gotp;
	struct xfs_bmbt_irec            got;
	struct xfs_mount		*mp = ip->i_mount;
	struct xfs_ifork		*ifp;
	xfs_extnum_t			nexts = 0;
6055
	xfs_extnum_t			current_ext;
6056 6057
	xfs_extnum_t			total_extents;
	xfs_extnum_t			stop_extent;
6058 6059
	int				error = 0;
	int				whichfork = XFS_DATA_FORK;
6060
	int				logflags = 0;
6061 6062 6063 6064 6065 6066 6067

	if (unlikely(XFS_TEST_ERROR(
	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
		XFS_ERROR_REPORT("xfs_bmap_shift_extents",
				 XFS_ERRLEVEL_LOW, mp);
D
Dave Chinner 已提交
6068
		return -EFSCORRUPTED;
6069 6070 6071
	}

	if (XFS_FORCED_SHUTDOWN(mp))
D
Dave Chinner 已提交
6072
		return -EIO;
6073

6074 6075
	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
6076 6077
	ASSERT(direction == SHIFT_LEFT || direction == SHIFT_RIGHT);
	ASSERT(*next_fsb != NULLFSBLOCK || direction == SHIFT_RIGHT);
6078 6079 6080 6081 6082 6083 6084 6085 6086

	ifp = XFS_IFORK_PTR(ip, whichfork);
	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
		/* Read in all the extents */
		error = xfs_iread_extents(tp, ip, whichfork);
		if (error)
			return error;
	}

6087 6088 6089
	if (ifp->if_flags & XFS_IFBROOT) {
		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
		cur->bc_private.b.firstblock = *firstblock;
6090
		cur->bc_private.b.dfops = dfops;
6091 6092 6093
		cur->bc_private.b.flags = 0;
	}

6094 6095 6096 6097 6098 6099 6100 6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113 6114 6115 6116 6117 6118 6119 6120 6121 6122 6123 6124 6125
	/*
	 * There may be delalloc extents in the data fork before the range we
	 * are collapsing out, so we cannot use the count of real extents here.
	 * Instead we have to calculate it from the incore fork.
	 */
	total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
	if (total_extents == 0) {
		*done = 1;
		goto del_cursor;
	}

	/*
	 * In case of first right shift, we need to initialize next_fsb
	 */
	if (*next_fsb == NULLFSBLOCK) {
		gotp = xfs_iext_get_ext(ifp, total_extents - 1);
		xfs_bmbt_get_all(gotp, &got);
		*next_fsb = got.br_startoff;
		if (stop_fsb > *next_fsb) {
			*done = 1;
			goto del_cursor;
		}
	}

	/* Lookup the extent index at which we have to stop */
	if (direction == SHIFT_RIGHT) {
		gotp = xfs_iext_bno_to_ext(ifp, stop_fsb, &stop_extent);
		/* Make stop_extent exclusive of shift range */
		stop_extent--;
	} else
		stop_extent = total_extents;

6126
	/*
6127 6128 6129 6130 6131
	 * Look up the extent index for the fsb where we start shifting. We can
	 * henceforth iterate with current_ext as extent list changes are locked
	 * out via ilock.
	 *
	 * gotp can be null in 2 cases: 1) if there are no extents or 2)
6132
	 * *next_fsb lies in a hole beyond which there are no extents. Either
6133
	 * way, we are done.
6134
	 */
6135
	gotp = xfs_iext_bno_to_ext(ifp, *next_fsb, &current_ext);
6136 6137
	if (!gotp) {
		*done = 1;
6138
		goto del_cursor;
6139 6140
	}

6141 6142 6143 6144 6145 6146 6147 6148
	/* some sanity checking before we finally start shifting extents */
	if ((direction == SHIFT_LEFT && current_ext >= stop_extent) ||
	     (direction == SHIFT_RIGHT && current_ext <= stop_extent)) {
		error = -EIO;
		goto del_cursor;
	}

	while (nexts++ < num_exts) {
6149
		error = xfs_bmse_shift_one(ip, whichfork, offset_shift_fsb,
6150
					   &current_ext, gotp, cur, &logflags,
6151
					   direction, dfops);
6152 6153
		if (error)
			goto del_cursor;
6154 6155 6156 6157 6158 6159 6160 6161
		/*
		 * If there was an extent merge during the shift, the extent
		 * count can change. Update the total and grade the next record.
		 */
		if (direction == SHIFT_LEFT) {
			total_extents = ifp->if_bytes / sizeof(xfs_bmbt_rec_t);
			stop_extent = total_extents;
		}
6162

6163 6164 6165
		if (current_ext == stop_extent) {
			*done = 1;
			*next_fsb = NULLFSBLOCK;
6166
			break;
6167
		}
6168
		gotp = xfs_iext_get_ext(ifp, current_ext);
6169 6170
	}

6171
	if (!*done) {
6172
		xfs_bmbt_get_all(gotp, &got);
6173
		*next_fsb = got.br_startoff;
6174
	}
6175 6176 6177 6178 6179 6180

del_cursor:
	if (cur)
		xfs_btree_del_cursor(cur,
			error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);

6181 6182
	if (logflags)
		xfs_trans_log_inode(tp, ip, logflags);
6183

6184 6185
	return error;
}
6186 6187 6188 6189 6190 6191 6192 6193 6194 6195 6196 6197 6198

/*
 * Splits an extent into two extents at split_fsb block such that it is
 * the first block of the current_ext. @current_ext is a target extent
 * to be split. @split_fsb is a block where the extents is split.
 * If split_fsb lies in a hole or the first block of extents, just return 0.
 */
STATIC int
xfs_bmap_split_extent_at(
	struct xfs_trans	*tp,
	struct xfs_inode	*ip,
	xfs_fileoff_t		split_fsb,
	xfs_fsblock_t		*firstfsb,
6199
	struct xfs_defer_ops	*dfops)
6200 6201 6202 6203 6204 6205 6206 6207 6208 6209 6210 6211 6212 6213 6214 6215 6216 6217 6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228 6229 6230 6231 6232 6233 6234 6235 6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246 6247 6248 6249 6250 6251 6252 6253 6254 6255 6256 6257 6258 6259 6260
{
	int				whichfork = XFS_DATA_FORK;
	struct xfs_btree_cur		*cur = NULL;
	struct xfs_bmbt_rec_host	*gotp;
	struct xfs_bmbt_irec		got;
	struct xfs_bmbt_irec		new; /* split extent */
	struct xfs_mount		*mp = ip->i_mount;
	struct xfs_ifork		*ifp;
	xfs_fsblock_t			gotblkcnt; /* new block count for got */
	xfs_extnum_t			current_ext;
	int				error = 0;
	int				logflags = 0;
	int				i = 0;

	if (unlikely(XFS_TEST_ERROR(
	    (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_EXTENTS &&
	     XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE),
	     mp, XFS_ERRTAG_BMAPIFORMAT, XFS_RANDOM_BMAPIFORMAT))) {
		XFS_ERROR_REPORT("xfs_bmap_split_extent_at",
				 XFS_ERRLEVEL_LOW, mp);
		return -EFSCORRUPTED;
	}

	if (XFS_FORCED_SHUTDOWN(mp))
		return -EIO;

	ifp = XFS_IFORK_PTR(ip, whichfork);
	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
		/* Read in all the extents */
		error = xfs_iread_extents(tp, ip, whichfork);
		if (error)
			return error;
	}

	/*
	 * gotp can be null in 2 cases: 1) if there are no extents
	 * or 2) split_fsb lies in a hole beyond which there are
	 * no extents. Either way, we are done.
	 */
	gotp = xfs_iext_bno_to_ext(ifp, split_fsb, &current_ext);
	if (!gotp)
		return 0;

	xfs_bmbt_get_all(gotp, &got);

	/*
	 * Check split_fsb lies in a hole or the start boundary offset
	 * of the extent.
	 */
	if (got.br_startoff >= split_fsb)
		return 0;

	gotblkcnt = split_fsb - got.br_startoff;
	new.br_startoff = split_fsb;
	new.br_startblock = got.br_startblock + gotblkcnt;
	new.br_blockcount = got.br_blockcount - gotblkcnt;
	new.br_state = got.br_state;

	if (ifp->if_flags & XFS_IFBROOT) {
		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
		cur->bc_private.b.firstblock = *firstfsb;
6261
		cur->bc_private.b.dfops = dfops;
6262 6263 6264 6265 6266 6267 6268 6269 6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284 6285 6286 6287 6288 6289 6290 6291 6292 6293 6294 6295 6296 6297 6298 6299 6300 6301 6302 6303 6304 6305 6306 6307 6308 6309 6310 6311 6312 6313
		cur->bc_private.b.flags = 0;
		error = xfs_bmbt_lookup_eq(cur, got.br_startoff,
				got.br_startblock,
				got.br_blockcount,
				&i);
		if (error)
			goto del_cursor;
		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
	}

	xfs_bmbt_set_blockcount(gotp, gotblkcnt);
	got.br_blockcount = gotblkcnt;

	logflags = XFS_ILOG_CORE;
	if (cur) {
		error = xfs_bmbt_update(cur, got.br_startoff,
				got.br_startblock,
				got.br_blockcount,
				got.br_state);
		if (error)
			goto del_cursor;
	} else
		logflags |= XFS_ILOG_DEXT;

	/* Add new extent */
	current_ext++;
	xfs_iext_insert(ip, current_ext, 1, &new, 0);
	XFS_IFORK_NEXT_SET(ip, whichfork,
			   XFS_IFORK_NEXTENTS(ip, whichfork) + 1);

	if (cur) {
		error = xfs_bmbt_lookup_eq(cur, new.br_startoff,
				new.br_startblock, new.br_blockcount,
				&i);
		if (error)
			goto del_cursor;
		XFS_WANT_CORRUPTED_GOTO(mp, i == 0, del_cursor);
		cur->bc_rec.b.br_state = new.br_state;

		error = xfs_btree_insert(cur, &i);
		if (error)
			goto del_cursor;
		XFS_WANT_CORRUPTED_GOTO(mp, i == 1, del_cursor);
	}

	/*
	 * Convert to a btree if necessary.
	 */
	if (xfs_bmap_needs_btree(ip, whichfork)) {
		int tmp_logflags; /* partial log flag return val */

		ASSERT(cur == NULL);
6314
		error = xfs_bmap_extents_to_btree(tp, ip, firstfsb, dfops,
6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326 6327 6328 6329 6330 6331 6332 6333 6334 6335 6336 6337
				&cur, 0, &tmp_logflags, whichfork);
		logflags |= tmp_logflags;
	}

del_cursor:
	if (cur) {
		cur->bc_private.b.allocated = 0;
		xfs_btree_del_cursor(cur,
				error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
	}

	if (logflags)
		xfs_trans_log_inode(tp, ip, logflags);
	return error;
}

int
xfs_bmap_split_extent(
	struct xfs_inode        *ip,
	xfs_fileoff_t           split_fsb)
{
	struct xfs_mount        *mp = ip->i_mount;
	struct xfs_trans        *tp;
6338
	struct xfs_defer_ops    dfops;
6339 6340 6341
	xfs_fsblock_t           firstfsb;
	int                     error;

6342 6343 6344
	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write,
			XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp);
	if (error)
6345 6346 6347 6348 6349
		return error;

	xfs_ilock(ip, XFS_ILOCK_EXCL);
	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);

6350
	xfs_defer_init(&dfops, &firstfsb);
6351 6352

	error = xfs_bmap_split_extent_at(tp, ip, split_fsb,
6353
			&firstfsb, &dfops);
6354 6355 6356
	if (error)
		goto out;

6357
	error = xfs_defer_finish(&tp, &dfops, NULL);
6358 6359 6360
	if (error)
		goto out;

6361
	return xfs_trans_commit(tp);
6362 6363

out:
6364
	xfs_defer_cancel(&dfops);
6365
	xfs_trans_cancel(tp);
6366 6367
	return error;
}
6368 6369 6370 6371 6372 6373 6374 6375 6376 6377 6378 6379 6380 6381 6382 6383 6384 6385 6386 6387 6388 6389 6390 6391 6392 6393 6394 6395 6396 6397 6398 6399 6400 6401 6402 6403 6404 6405 6406 6407 6408 6409 6410 6411 6412 6413 6414 6415 6416 6417 6418 6419 6420 6421 6422 6423 6424 6425 6426 6427 6428 6429 6430 6431 6432 6433 6434 6435 6436 6437 6438 6439 6440 6441 6442 6443 6444 6445 6446 6447 6448 6449 6450 6451 6452 6453 6454 6455 6456 6457 6458 6459 6460 6461 6462 6463 6464 6465 6466 6467 6468 6469 6470 6471 6472 6473 6474 6475 6476 6477 6478 6479 6480 6481 6482 6483 6484 6485 6486 6487 6488 6489 6490 6491 6492 6493 6494 6495 6496 6497 6498 6499 6500 6501 6502 6503 6504 6505 6506 6507 6508 6509 6510

/* Deferred mapping is only for real extents in the data fork. */
static bool
xfs_bmap_is_update_needed(
	struct xfs_bmbt_irec	*bmap)
{
	return  bmap->br_startblock != HOLESTARTBLOCK &&
		bmap->br_startblock != DELAYSTARTBLOCK;
}

/* Record a bmap intent. */
static int
__xfs_bmap_add(
	struct xfs_mount		*mp,
	struct xfs_defer_ops		*dfops,
	enum xfs_bmap_intent_type	type,
	struct xfs_inode		*ip,
	int				whichfork,
	struct xfs_bmbt_irec		*bmap)
{
	int				error;
	struct xfs_bmap_intent		*bi;

	trace_xfs_bmap_defer(mp,
			XFS_FSB_TO_AGNO(mp, bmap->br_startblock),
			type,
			XFS_FSB_TO_AGBNO(mp, bmap->br_startblock),
			ip->i_ino, whichfork,
			bmap->br_startoff,
			bmap->br_blockcount,
			bmap->br_state);

	bi = kmem_alloc(sizeof(struct xfs_bmap_intent), KM_SLEEP | KM_NOFS);
	INIT_LIST_HEAD(&bi->bi_list);
	bi->bi_type = type;
	bi->bi_owner = ip;
	bi->bi_whichfork = whichfork;
	bi->bi_bmap = *bmap;

	error = xfs_defer_join(dfops, bi->bi_owner);
	if (error) {
		kmem_free(bi);
		return error;
	}

	xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list);
	return 0;
}

/* Map an extent into a file. */
int
xfs_bmap_map_extent(
	struct xfs_mount	*mp,
	struct xfs_defer_ops	*dfops,
	struct xfs_inode	*ip,
	struct xfs_bmbt_irec	*PREV)
{
	if (!xfs_bmap_is_update_needed(PREV))
		return 0;

	return __xfs_bmap_add(mp, dfops, XFS_BMAP_MAP, ip,
			XFS_DATA_FORK, PREV);
}

/* Unmap an extent out of a file. */
int
xfs_bmap_unmap_extent(
	struct xfs_mount	*mp,
	struct xfs_defer_ops	*dfops,
	struct xfs_inode	*ip,
	struct xfs_bmbt_irec	*PREV)
{
	if (!xfs_bmap_is_update_needed(PREV))
		return 0;

	return __xfs_bmap_add(mp, dfops, XFS_BMAP_UNMAP, ip,
			XFS_DATA_FORK, PREV);
}

/*
 * Process one of the deferred bmap operations.  We pass back the
 * btree cursor to maintain our lock on the bmapbt between calls.
 */
int
xfs_bmap_finish_one(
	struct xfs_trans		*tp,
	struct xfs_defer_ops		*dfops,
	struct xfs_inode		*ip,
	enum xfs_bmap_intent_type	type,
	int				whichfork,
	xfs_fileoff_t			startoff,
	xfs_fsblock_t			startblock,
	xfs_filblks_t			blockcount,
	xfs_exntst_t			state)
{
	struct xfs_bmbt_irec		bmap;
	int				nimaps = 1;
	xfs_fsblock_t			firstfsb;
	int				flags = XFS_BMAPI_REMAP;
	int				done;
	int				error = 0;

	bmap.br_startblock = startblock;
	bmap.br_startoff = startoff;
	bmap.br_blockcount = blockcount;
	bmap.br_state = state;

	trace_xfs_bmap_deferred(tp->t_mountp,
			XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
			XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
			ip->i_ino, whichfork, startoff, blockcount, state);

	if (whichfork != XFS_DATA_FORK && whichfork != XFS_ATTR_FORK)
		return -EFSCORRUPTED;
	if (whichfork == XFS_ATTR_FORK)
		flags |= XFS_BMAPI_ATTRFORK;

	if (XFS_TEST_ERROR(false, tp->t_mountp,
			XFS_ERRTAG_BMAP_FINISH_ONE,
			XFS_RANDOM_BMAP_FINISH_ONE))
		return -EIO;

	switch (type) {
	case XFS_BMAP_MAP:
		firstfsb = bmap.br_startblock;
		error = xfs_bmapi_write(tp, ip, bmap.br_startoff,
					bmap.br_blockcount, flags, &firstfsb,
					bmap.br_blockcount, &bmap, &nimaps,
					dfops);
		break;
	case XFS_BMAP_UNMAP:
		error = xfs_bunmapi(tp, ip, bmap.br_startoff,
				bmap.br_blockcount, flags, 1, &firstfsb,
				dfops, &done);
		ASSERT(done);
		break;
	default:
		ASSERT(0);
		error = -EFSCORRUPTED;
	}

	return error;
}