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v6.8
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#include "xfs.h"
   7#include "xfs_fs.h"
   8#include "xfs_shared.h"
   9#include "xfs_format.h"
  10#include "xfs_log_format.h"
  11#include "xfs_trans_resv.h"
  12#include "xfs_bit.h"
  13#include "xfs_mount.h"
  14#include "xfs_inode.h"
  15#include "xfs_btree.h"
  16#include "xfs_ialloc.h"
  17#include "xfs_ialloc_btree.h"
  18#include "xfs_alloc.h"
  19#include "xfs_errortag.h"
  20#include "xfs_error.h"
  21#include "xfs_bmap.h"
  22#include "xfs_trans.h"
  23#include "xfs_buf_item.h"
  24#include "xfs_icreate_item.h"
  25#include "xfs_icache.h"
  26#include "xfs_trace.h"
  27#include "xfs_log.h"
  28#include "xfs_rmap.h"
  29#include "xfs_ag.h"
  30
  31/*
  32 * Lookup a record by ino in the btree given by cur.
  33 */
  34int					/* error */
  35xfs_inobt_lookup(
  36	struct xfs_btree_cur	*cur,	/* btree cursor */
  37	xfs_agino_t		ino,	/* starting inode of chunk */
  38	xfs_lookup_t		dir,	/* <=, >=, == */
  39	int			*stat)	/* success/failure */
  40{
  41	cur->bc_rec.i.ir_startino = ino;
  42	cur->bc_rec.i.ir_holemask = 0;
  43	cur->bc_rec.i.ir_count = 0;
  44	cur->bc_rec.i.ir_freecount = 0;
  45	cur->bc_rec.i.ir_free = 0;
  46	return xfs_btree_lookup(cur, dir, stat);
  47}
  48
  49/*
  50 * Update the record referred to by cur to the value given.
  51 * This either works (return 0) or gets an EFSCORRUPTED error.
  52 */
  53STATIC int				/* error */
  54xfs_inobt_update(
  55	struct xfs_btree_cur	*cur,	/* btree cursor */
  56	xfs_inobt_rec_incore_t	*irec)	/* btree record */
  57{
  58	union xfs_btree_rec	rec;
  59
  60	rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
  61	if (xfs_has_sparseinodes(cur->bc_mp)) {
  62		rec.inobt.ir_u.sp.ir_holemask = cpu_to_be16(irec->ir_holemask);
  63		rec.inobt.ir_u.sp.ir_count = irec->ir_count;
  64		rec.inobt.ir_u.sp.ir_freecount = irec->ir_freecount;
  65	} else {
  66		/* ir_holemask/ir_count not supported on-disk */
  67		rec.inobt.ir_u.f.ir_freecount = cpu_to_be32(irec->ir_freecount);
  68	}
  69	rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
  70	return xfs_btree_update(cur, &rec);
  71}
  72
  73/* Convert on-disk btree record to incore inobt record. */
  74void
  75xfs_inobt_btrec_to_irec(
  76	struct xfs_mount		*mp,
  77	const union xfs_btree_rec	*rec,
  78	struct xfs_inobt_rec_incore	*irec)
  79{
  80	irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
  81	if (xfs_has_sparseinodes(mp)) {
  82		irec->ir_holemask = be16_to_cpu(rec->inobt.ir_u.sp.ir_holemask);
  83		irec->ir_count = rec->inobt.ir_u.sp.ir_count;
  84		irec->ir_freecount = rec->inobt.ir_u.sp.ir_freecount;
  85	} else {
  86		/*
  87		 * ir_holemask/ir_count not supported on-disk. Fill in hardcoded
  88		 * values for full inode chunks.
  89		 */
  90		irec->ir_holemask = XFS_INOBT_HOLEMASK_FULL;
  91		irec->ir_count = XFS_INODES_PER_CHUNK;
  92		irec->ir_freecount =
  93				be32_to_cpu(rec->inobt.ir_u.f.ir_freecount);
  94	}
  95	irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
  96}
  97
  98/* Compute the freecount of an incore inode record. */
  99uint8_t
 100xfs_inobt_rec_freecount(
 101	const struct xfs_inobt_rec_incore	*irec)
 102{
 103	uint64_t				realfree = irec->ir_free;
 104
 105	if (xfs_inobt_issparse(irec->ir_holemask))
 106		realfree &= xfs_inobt_irec_to_allocmask(irec);
 107	return hweight64(realfree);
 108}
 109
 110/* Simple checks for inode records. */
 111xfs_failaddr_t
 112xfs_inobt_check_irec(
 113	struct xfs_perag			*pag,
 114	const struct xfs_inobt_rec_incore	*irec)
 115{
 116	/* Record has to be properly aligned within the AG. */
 117	if (!xfs_verify_agino(pag, irec->ir_startino))
 118		return __this_address;
 119	if (!xfs_verify_agino(pag,
 120				irec->ir_startino + XFS_INODES_PER_CHUNK - 1))
 121		return __this_address;
 122	if (irec->ir_count < XFS_INODES_PER_HOLEMASK_BIT ||
 123	    irec->ir_count > XFS_INODES_PER_CHUNK)
 124		return __this_address;
 125	if (irec->ir_freecount > XFS_INODES_PER_CHUNK)
 126		return __this_address;
 127
 128	if (xfs_inobt_rec_freecount(irec) != irec->ir_freecount)
 129		return __this_address;
 130
 131	return NULL;
 132}
 133
 134static inline int
 135xfs_inobt_complain_bad_rec(
 136	struct xfs_btree_cur		*cur,
 137	xfs_failaddr_t			fa,
 138	const struct xfs_inobt_rec_incore *irec)
 139{
 140	struct xfs_mount		*mp = cur->bc_mp;
 141
 142	xfs_warn(mp,
 143		"%s Inode BTree record corruption in AG %d detected at %pS!",
 144		cur->bc_btnum == XFS_BTNUM_INO ? "Used" : "Free",
 145		cur->bc_ag.pag->pag_agno, fa);
 146	xfs_warn(mp,
 147"start inode 0x%x, count 0x%x, free 0x%x freemask 0x%llx, holemask 0x%x",
 148		irec->ir_startino, irec->ir_count, irec->ir_freecount,
 149		irec->ir_free, irec->ir_holemask);
 150	return -EFSCORRUPTED;
 151}
 152
 153/*
 154 * Get the data from the pointed-to record.
 155 */
 156int
 157xfs_inobt_get_rec(
 158	struct xfs_btree_cur		*cur,
 159	struct xfs_inobt_rec_incore	*irec,
 160	int				*stat)
 161{
 162	struct xfs_mount		*mp = cur->bc_mp;
 
 163	union xfs_btree_rec		*rec;
 164	xfs_failaddr_t			fa;
 165	int				error;
 
 166
 167	error = xfs_btree_get_rec(cur, &rec, stat);
 168	if (error || *stat == 0)
 169		return error;
 170
 171	xfs_inobt_btrec_to_irec(mp, rec, irec);
 172	fa = xfs_inobt_check_irec(cur->bc_ag.pag, irec);
 173	if (fa)
 174		return xfs_inobt_complain_bad_rec(cur, fa, irec);
 
 
 
 
 
 
 
 
 
 
 
 
 
 175
 176	return 0;
 
 
 
 
 
 
 
 
 
 
 177}
 178
 179/*
 180 * Insert a single inobt record. Cursor must already point to desired location.
 181 */
 182int
 183xfs_inobt_insert_rec(
 184	struct xfs_btree_cur	*cur,
 185	uint16_t		holemask,
 186	uint8_t			count,
 187	int32_t			freecount,
 188	xfs_inofree_t		free,
 189	int			*stat)
 190{
 191	cur->bc_rec.i.ir_holemask = holemask;
 192	cur->bc_rec.i.ir_count = count;
 193	cur->bc_rec.i.ir_freecount = freecount;
 194	cur->bc_rec.i.ir_free = free;
 195	return xfs_btree_insert(cur, stat);
 196}
 197
 198/*
 199 * Insert records describing a newly allocated inode chunk into the inobt.
 200 */
 201STATIC int
 202xfs_inobt_insert(
 203	struct xfs_perag	*pag,
 204	struct xfs_trans	*tp,
 205	struct xfs_buf		*agbp,
 
 206	xfs_agino_t		newino,
 207	xfs_agino_t		newlen,
 208	xfs_btnum_t		btnum)
 209{
 210	struct xfs_btree_cur	*cur;
 211	xfs_agino_t		thisino;
 212	int			i;
 213	int			error;
 214
 215	cur = xfs_inobt_init_cursor(pag, tp, agbp, btnum);
 216
 217	for (thisino = newino;
 218	     thisino < newino + newlen;
 219	     thisino += XFS_INODES_PER_CHUNK) {
 220		error = xfs_inobt_lookup(cur, thisino, XFS_LOOKUP_EQ, &i);
 221		if (error) {
 222			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 223			return error;
 224		}
 225		ASSERT(i == 0);
 226
 227		error = xfs_inobt_insert_rec(cur, XFS_INOBT_HOLEMASK_FULL,
 228					     XFS_INODES_PER_CHUNK,
 229					     XFS_INODES_PER_CHUNK,
 230					     XFS_INOBT_ALL_FREE, &i);
 231		if (error) {
 232			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 233			return error;
 234		}
 235		ASSERT(i == 1);
 236	}
 237
 238	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 239
 240	return 0;
 241}
 242
 243/*
 244 * Verify that the number of free inodes in the AGI is correct.
 245 */
 246#ifdef DEBUG
 247static int
 248xfs_check_agi_freecount(
 249	struct xfs_btree_cur	*cur)
 250{
 251	if (cur->bc_nlevels == 1) {
 252		xfs_inobt_rec_incore_t rec;
 253		int		freecount = 0;
 254		int		error;
 255		int		i;
 256
 257		error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
 258		if (error)
 259			return error;
 260
 261		do {
 262			error = xfs_inobt_get_rec(cur, &rec, &i);
 263			if (error)
 264				return error;
 265
 266			if (i) {
 267				freecount += rec.ir_freecount;
 268				error = xfs_btree_increment(cur, 0, &i);
 269				if (error)
 270					return error;
 271			}
 272		} while (i == 1);
 273
 274		if (!xfs_is_shutdown(cur->bc_mp))
 275			ASSERT(freecount == cur->bc_ag.pag->pagi_freecount);
 276	}
 277	return 0;
 278}
 279#else
 280#define xfs_check_agi_freecount(cur)	0
 281#endif
 282
 283/*
 284 * Initialise a new set of inodes. When called without a transaction context
 285 * (e.g. from recovery) we initiate a delayed write of the inode buffers rather
 286 * than logging them (which in a transaction context puts them into the AIL
 287 * for writeback rather than the xfsbufd queue).
 288 */
 289int
 290xfs_ialloc_inode_init(
 291	struct xfs_mount	*mp,
 292	struct xfs_trans	*tp,
 293	struct list_head	*buffer_list,
 294	int			icount,
 295	xfs_agnumber_t		agno,
 296	xfs_agblock_t		agbno,
 297	xfs_agblock_t		length,
 298	unsigned int		gen)
 299{
 300	struct xfs_buf		*fbuf;
 301	struct xfs_dinode	*free;
 302	int			nbufs;
 303	int			version;
 304	int			i, j;
 305	xfs_daddr_t		d;
 306	xfs_ino_t		ino = 0;
 307	int			error;
 308
 309	/*
 310	 * Loop over the new block(s), filling in the inodes.  For small block
 311	 * sizes, manipulate the inodes in buffers  which are multiples of the
 312	 * blocks size.
 313	 */
 314	nbufs = length / M_IGEO(mp)->blocks_per_cluster;
 315
 316	/*
 317	 * Figure out what version number to use in the inodes we create.  If
 318	 * the superblock version has caught up to the one that supports the new
 319	 * inode format, then use the new inode version.  Otherwise use the old
 320	 * version so that old kernels will continue to be able to use the file
 321	 * system.
 322	 *
 323	 * For v3 inodes, we also need to write the inode number into the inode,
 324	 * so calculate the first inode number of the chunk here as
 325	 * XFS_AGB_TO_AGINO() only works within a filesystem block, not
 326	 * across multiple filesystem blocks (such as a cluster) and so cannot
 327	 * be used in the cluster buffer loop below.
 328	 *
 329	 * Further, because we are writing the inode directly into the buffer
 330	 * and calculating a CRC on the entire inode, we have ot log the entire
 331	 * inode so that the entire range the CRC covers is present in the log.
 332	 * That means for v3 inode we log the entire buffer rather than just the
 333	 * inode cores.
 334	 */
 335	if (xfs_has_v3inodes(mp)) {
 336		version = 3;
 337		ino = XFS_AGINO_TO_INO(mp, agno, XFS_AGB_TO_AGINO(mp, agbno));
 338
 339		/*
 340		 * log the initialisation that is about to take place as an
 341		 * logical operation. This means the transaction does not
 342		 * need to log the physical changes to the inode buffers as log
 343		 * recovery will know what initialisation is actually needed.
 344		 * Hence we only need to log the buffers as "ordered" buffers so
 345		 * they track in the AIL as if they were physically logged.
 346		 */
 347		if (tp)
 348			xfs_icreate_log(tp, agno, agbno, icount,
 349					mp->m_sb.sb_inodesize, length, gen);
 350	} else
 351		version = 2;
 352
 353	for (j = 0; j < nbufs; j++) {
 354		/*
 355		 * Get the block.
 356		 */
 357		d = XFS_AGB_TO_DADDR(mp, agno, agbno +
 358				(j * M_IGEO(mp)->blocks_per_cluster));
 359		error = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 360				mp->m_bsize * M_IGEO(mp)->blocks_per_cluster,
 361				XBF_UNMAPPED, &fbuf);
 362		if (error)
 363			return error;
 364
 365		/* Initialize the inode buffers and log them appropriately. */
 366		fbuf->b_ops = &xfs_inode_buf_ops;
 367		xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
 368		for (i = 0; i < M_IGEO(mp)->inodes_per_cluster; i++) {
 369			int	ioffset = i << mp->m_sb.sb_inodelog;
 
 370
 371			free = xfs_make_iptr(mp, fbuf, i);
 372			free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
 373			free->di_version = version;
 374			free->di_gen = cpu_to_be32(gen);
 375			free->di_next_unlinked = cpu_to_be32(NULLAGINO);
 376
 377			if (version == 3) {
 378				free->di_ino = cpu_to_be64(ino);
 379				ino++;
 380				uuid_copy(&free->di_uuid,
 381					  &mp->m_sb.sb_meta_uuid);
 382				xfs_dinode_calc_crc(mp, free);
 383			} else if (tp) {
 384				/* just log the inode core */
 385				xfs_trans_log_buf(tp, fbuf, ioffset,
 386					  ioffset + XFS_DINODE_SIZE(mp) - 1);
 387			}
 388		}
 389
 390		if (tp) {
 391			/*
 392			 * Mark the buffer as an inode allocation buffer so it
 393			 * sticks in AIL at the point of this allocation
 394			 * transaction. This ensures the they are on disk before
 395			 * the tail of the log can be moved past this
 396			 * transaction (i.e. by preventing relogging from moving
 397			 * it forward in the log).
 398			 */
 399			xfs_trans_inode_alloc_buf(tp, fbuf);
 400			if (version == 3) {
 401				/*
 402				 * Mark the buffer as ordered so that they are
 403				 * not physically logged in the transaction but
 404				 * still tracked in the AIL as part of the
 405				 * transaction and pin the log appropriately.
 406				 */
 407				xfs_trans_ordered_buf(tp, fbuf);
 408			}
 409		} else {
 410			fbuf->b_flags |= XBF_DONE;
 411			xfs_buf_delwri_queue(fbuf, buffer_list);
 412			xfs_buf_relse(fbuf);
 413		}
 414	}
 415	return 0;
 416}
 417
 418/*
 419 * Align startino and allocmask for a recently allocated sparse chunk such that
 420 * they are fit for insertion (or merge) into the on-disk inode btrees.
 421 *
 422 * Background:
 423 *
 424 * When enabled, sparse inode support increases the inode alignment from cluster
 425 * size to inode chunk size. This means that the minimum range between two
 426 * non-adjacent inode records in the inobt is large enough for a full inode
 427 * record. This allows for cluster sized, cluster aligned block allocation
 428 * without need to worry about whether the resulting inode record overlaps with
 429 * another record in the tree. Without this basic rule, we would have to deal
 430 * with the consequences of overlap by potentially undoing recent allocations in
 431 * the inode allocation codepath.
 432 *
 433 * Because of this alignment rule (which is enforced on mount), there are two
 434 * inobt possibilities for newly allocated sparse chunks. One is that the
 435 * aligned inode record for the chunk covers a range of inodes not already
 436 * covered in the inobt (i.e., it is safe to insert a new sparse record). The
 437 * other is that a record already exists at the aligned startino that considers
 438 * the newly allocated range as sparse. In the latter case, record content is
 439 * merged in hope that sparse inode chunks fill to full chunks over time.
 440 */
 441STATIC void
 442xfs_align_sparse_ino(
 443	struct xfs_mount		*mp,
 444	xfs_agino_t			*startino,
 445	uint16_t			*allocmask)
 446{
 447	xfs_agblock_t			agbno;
 448	xfs_agblock_t			mod;
 449	int				offset;
 450
 451	agbno = XFS_AGINO_TO_AGBNO(mp, *startino);
 452	mod = agbno % mp->m_sb.sb_inoalignmt;
 453	if (!mod)
 454		return;
 455
 456	/* calculate the inode offset and align startino */
 457	offset = XFS_AGB_TO_AGINO(mp, mod);
 458	*startino -= offset;
 459
 460	/*
 461	 * Since startino has been aligned down, left shift allocmask such that
 462	 * it continues to represent the same physical inodes relative to the
 463	 * new startino.
 464	 */
 465	*allocmask <<= offset / XFS_INODES_PER_HOLEMASK_BIT;
 466}
 467
 468/*
 469 * Determine whether the source inode record can merge into the target. Both
 470 * records must be sparse, the inode ranges must match and there must be no
 471 * allocation overlap between the records.
 472 */
 473STATIC bool
 474__xfs_inobt_can_merge(
 475	struct xfs_inobt_rec_incore	*trec,	/* tgt record */
 476	struct xfs_inobt_rec_incore	*srec)	/* src record */
 477{
 478	uint64_t			talloc;
 479	uint64_t			salloc;
 480
 481	/* records must cover the same inode range */
 482	if (trec->ir_startino != srec->ir_startino)
 483		return false;
 484
 485	/* both records must be sparse */
 486	if (!xfs_inobt_issparse(trec->ir_holemask) ||
 487	    !xfs_inobt_issparse(srec->ir_holemask))
 488		return false;
 489
 490	/* both records must track some inodes */
 491	if (!trec->ir_count || !srec->ir_count)
 492		return false;
 493
 494	/* can't exceed capacity of a full record */
 495	if (trec->ir_count + srec->ir_count > XFS_INODES_PER_CHUNK)
 496		return false;
 497
 498	/* verify there is no allocation overlap */
 499	talloc = xfs_inobt_irec_to_allocmask(trec);
 500	salloc = xfs_inobt_irec_to_allocmask(srec);
 501	if (talloc & salloc)
 502		return false;
 503
 504	return true;
 505}
 506
 507/*
 508 * Merge the source inode record into the target. The caller must call
 509 * __xfs_inobt_can_merge() to ensure the merge is valid.
 510 */
 511STATIC void
 512__xfs_inobt_rec_merge(
 513	struct xfs_inobt_rec_incore	*trec,	/* target */
 514	struct xfs_inobt_rec_incore	*srec)	/* src */
 515{
 516	ASSERT(trec->ir_startino == srec->ir_startino);
 517
 518	/* combine the counts */
 519	trec->ir_count += srec->ir_count;
 520	trec->ir_freecount += srec->ir_freecount;
 521
 522	/*
 523	 * Merge the holemask and free mask. For both fields, 0 bits refer to
 524	 * allocated inodes. We combine the allocated ranges with bitwise AND.
 525	 */
 526	trec->ir_holemask &= srec->ir_holemask;
 527	trec->ir_free &= srec->ir_free;
 528}
 529
 530/*
 531 * Insert a new sparse inode chunk into the associated inode btree. The inode
 532 * record for the sparse chunk is pre-aligned to a startino that should match
 533 * any pre-existing sparse inode record in the tree. This allows sparse chunks
 534 * to fill over time.
 535 *
 536 * This function supports two modes of handling preexisting records depending on
 537 * the merge flag. If merge is true, the provided record is merged with the
 538 * existing record and updated in place. The merged record is returned in nrec.
 539 * If merge is false, an existing record is replaced with the provided record.
 540 * If no preexisting record exists, the provided record is always inserted.
 541 *
 542 * It is considered corruption if a merge is requested and not possible. Given
 543 * the sparse inode alignment constraints, this should never happen.
 544 */
 545STATIC int
 546xfs_inobt_insert_sprec(
 547	struct xfs_perag		*pag,
 548	struct xfs_trans		*tp,
 549	struct xfs_buf			*agbp,
 
 550	int				btnum,
 551	struct xfs_inobt_rec_incore	*nrec,	/* in/out: new/merged rec. */
 552	bool				merge)	/* merge or replace */
 553{
 554	struct xfs_mount		*mp = pag->pag_mount;
 555	struct xfs_btree_cur		*cur;
 556	int				error;
 557	int				i;
 558	struct xfs_inobt_rec_incore	rec;
 559
 560	cur = xfs_inobt_init_cursor(pag, tp, agbp, btnum);
 561
 562	/* the new record is pre-aligned so we know where to look */
 563	error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
 564	if (error)
 565		goto error;
 566	/* if nothing there, insert a new record and return */
 567	if (i == 0) {
 568		error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
 569					     nrec->ir_count, nrec->ir_freecount,
 570					     nrec->ir_free, &i);
 571		if (error)
 572			goto error;
 573		if (XFS_IS_CORRUPT(mp, i != 1)) {
 574			error = -EFSCORRUPTED;
 575			goto error;
 576		}
 577
 578		goto out;
 579	}
 580
 581	/*
 582	 * A record exists at this startino. Merge or replace the record
 583	 * depending on what we've been asked to do.
 584	 */
 585	if (merge) {
 586		error = xfs_inobt_get_rec(cur, &rec, &i);
 587		if (error)
 588			goto error;
 589		if (XFS_IS_CORRUPT(mp, i != 1)) {
 590			error = -EFSCORRUPTED;
 591			goto error;
 592		}
 593		if (XFS_IS_CORRUPT(mp, rec.ir_startino != nrec->ir_startino)) {
 594			error = -EFSCORRUPTED;
 595			goto error;
 596		}
 597
 598		/*
 599		 * This should never fail. If we have coexisting records that
 600		 * cannot merge, something is seriously wrong.
 601		 */
 602		if (XFS_IS_CORRUPT(mp, !__xfs_inobt_can_merge(nrec, &rec))) {
 603			error = -EFSCORRUPTED;
 604			goto error;
 605		}
 606
 607		trace_xfs_irec_merge_pre(mp, pag->pag_agno, rec.ir_startino,
 608					 rec.ir_holemask, nrec->ir_startino,
 609					 nrec->ir_holemask);
 610
 611		/* merge to nrec to output the updated record */
 612		__xfs_inobt_rec_merge(nrec, &rec);
 613
 614		trace_xfs_irec_merge_post(mp, pag->pag_agno, nrec->ir_startino,
 615					  nrec->ir_holemask);
 616
 617		error = xfs_inobt_rec_check_count(mp, nrec);
 618		if (error)
 619			goto error;
 620	}
 621
 622	error = xfs_inobt_update(cur, nrec);
 623	if (error)
 624		goto error;
 625
 626out:
 627	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 628	return 0;
 629error:
 630	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 631	return error;
 632}
 633
 634/*
 635 * Allocate new inodes in the allocation group specified by agbp.  Returns 0 if
 636 * inodes were allocated in this AG; -EAGAIN if there was no space in this AG so
 637 * the caller knows it can try another AG, a hard -ENOSPC when over the maximum
 638 * inode count threshold, or the usual negative error code for other errors.
 639 */
 640STATIC int
 641xfs_ialloc_ag_alloc(
 642	struct xfs_perag	*pag,
 643	struct xfs_trans	*tp,
 644	struct xfs_buf		*agbp)
 
 645{
 646	struct xfs_agi		*agi;
 647	struct xfs_alloc_arg	args;
 648	int			error;
 649	xfs_agino_t		newino;		/* new first inode's number */
 650	xfs_agino_t		newlen;		/* new number of inodes */
 651	int			isaligned = 0;	/* inode allocation at stripe */
 652						/* unit boundary */
 653	/* init. to full chunk */
 654	struct xfs_inobt_rec_incore rec;
 655	struct xfs_ino_geometry	*igeo = M_IGEO(tp->t_mountp);
 656	uint16_t		allocmask = (uint16_t) -1;
 657	int			do_sparse = 0;
 658
 659	memset(&args, 0, sizeof(args));
 660	args.tp = tp;
 661	args.mp = tp->t_mountp;
 662	args.fsbno = NULLFSBLOCK;
 663	args.oinfo = XFS_RMAP_OINFO_INODES;
 664	args.pag = pag;
 665
 666#ifdef DEBUG
 667	/* randomly do sparse inode allocations */
 668	if (xfs_has_sparseinodes(tp->t_mountp) &&
 669	    igeo->ialloc_min_blks < igeo->ialloc_blks)
 670		do_sparse = get_random_u32_below(2);
 671#endif
 672
 673	/*
 674	 * Locking will ensure that we don't have two callers in here
 675	 * at one time.
 676	 */
 677	newlen = igeo->ialloc_inos;
 678	if (igeo->maxicount &&
 679	    percpu_counter_read_positive(&args.mp->m_icount) + newlen >
 680							igeo->maxicount)
 681		return -ENOSPC;
 682	args.minlen = args.maxlen = igeo->ialloc_blks;
 683	/*
 684	 * First try to allocate inodes contiguous with the last-allocated
 685	 * chunk of inodes.  If the filesystem is striped, this will fill
 686	 * an entire stripe unit with inodes.
 687	 */
 688	agi = agbp->b_addr;
 689	newino = be32_to_cpu(agi->agi_newino);
 690	args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
 691		     igeo->ialloc_blks;
 692	if (do_sparse)
 693		goto sparse_alloc;
 694	if (likely(newino != NULLAGINO &&
 695		  (args.agbno < be32_to_cpu(agi->agi_length)))) {
 
 
 696		args.prod = 1;
 697
 698		/*
 699		 * We need to take into account alignment here to ensure that
 700		 * we don't modify the free list if we fail to have an exact
 701		 * block. If we don't have an exact match, and every oher
 702		 * attempt allocation attempt fails, we'll end up cancelling
 703		 * a dirty transaction and shutting down.
 704		 *
 705		 * For an exact allocation, alignment must be 1,
 706		 * however we need to take cluster alignment into account when
 707		 * fixing up the freelist. Use the minalignslop field to
 708		 * indicate that extra blocks might be required for alignment,
 709		 * but not to use them in the actual exact allocation.
 710		 */
 711		args.alignment = 1;
 712		args.minalignslop = igeo->cluster_align - 1;
 713
 714		/* Allow space for the inode btree to split. */
 715		args.minleft = igeo->inobt_maxlevels;
 716		error = xfs_alloc_vextent_exact_bno(&args,
 717				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 718						args.agbno));
 719		if (error)
 720			return error;
 721
 722		/*
 723		 * This request might have dirtied the transaction if the AG can
 724		 * satisfy the request, but the exact block was not available.
 725		 * If the allocation did fail, subsequent requests will relax
 726		 * the exact agbno requirement and increase the alignment
 727		 * instead. It is critical that the total size of the request
 728		 * (len + alignment + slop) does not increase from this point
 729		 * on, so reset minalignslop to ensure it is not included in
 730		 * subsequent requests.
 731		 */
 732		args.minalignslop = 0;
 733	}
 734
 735	if (unlikely(args.fsbno == NULLFSBLOCK)) {
 736		/*
 737		 * Set the alignment for the allocation.
 738		 * If stripe alignment is turned on then align at stripe unit
 739		 * boundary.
 740		 * If the cluster size is smaller than a filesystem block
 741		 * then we're doing I/O for inodes in filesystem block size
 742		 * pieces, so don't need alignment anyway.
 743		 */
 744		isaligned = 0;
 745		if (igeo->ialloc_align) {
 746			ASSERT(!xfs_has_noalign(args.mp));
 747			args.alignment = args.mp->m_dalign;
 748			isaligned = 1;
 749		} else
 750			args.alignment = igeo->cluster_align;
 751		/*
 
 
 
 
 
 
 
 752		 * Allocate a fixed-size extent of inodes.
 753		 */
 
 754		args.prod = 1;
 755		/*
 756		 * Allow space for the inode btree to split.
 757		 */
 758		args.minleft = igeo->inobt_maxlevels;
 759		error = xfs_alloc_vextent_near_bno(&args,
 760				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 761						be32_to_cpu(agi->agi_root)));
 762		if (error)
 763			return error;
 764	}
 765
 766	/*
 767	 * If stripe alignment is turned on, then try again with cluster
 768	 * alignment.
 769	 */
 770	if (isaligned && args.fsbno == NULLFSBLOCK) {
 
 
 
 771		args.alignment = igeo->cluster_align;
 772		error = xfs_alloc_vextent_near_bno(&args,
 773				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 774						be32_to_cpu(agi->agi_root)));
 775		if (error)
 776			return error;
 777	}
 778
 779	/*
 780	 * Finally, try a sparse allocation if the filesystem supports it and
 781	 * the sparse allocation length is smaller than a full chunk.
 782	 */
 783	if (xfs_has_sparseinodes(args.mp) &&
 784	    igeo->ialloc_min_blks < igeo->ialloc_blks &&
 785	    args.fsbno == NULLFSBLOCK) {
 786sparse_alloc:
 
 
 
 787		args.alignment = args.mp->m_sb.sb_spino_align;
 788		args.prod = 1;
 789
 790		args.minlen = igeo->ialloc_min_blks;
 791		args.maxlen = args.minlen;
 792
 793		/*
 794		 * The inode record will be aligned to full chunk size. We must
 795		 * prevent sparse allocation from AG boundaries that result in
 796		 * invalid inode records, such as records that start at agbno 0
 797		 * or extend beyond the AG.
 798		 *
 799		 * Set min agbno to the first aligned, non-zero agbno and max to
 800		 * the last aligned agbno that is at least one full chunk from
 801		 * the end of the AG.
 802		 */
 803		args.min_agbno = args.mp->m_sb.sb_inoalignmt;
 804		args.max_agbno = round_down(args.mp->m_sb.sb_agblocks,
 805					    args.mp->m_sb.sb_inoalignmt) -
 806				 igeo->ialloc_blks;
 807
 808		error = xfs_alloc_vextent_near_bno(&args,
 809				XFS_AGB_TO_FSB(args.mp, pag->pag_agno,
 810						be32_to_cpu(agi->agi_root)));
 811		if (error)
 812			return error;
 813
 814		newlen = XFS_AGB_TO_AGINO(args.mp, args.len);
 815		ASSERT(newlen <= XFS_INODES_PER_CHUNK);
 816		allocmask = (1 << (newlen / XFS_INODES_PER_HOLEMASK_BIT)) - 1;
 817	}
 818
 819	if (args.fsbno == NULLFSBLOCK)
 820		return -EAGAIN;
 821
 822	ASSERT(args.len == args.minlen);
 823
 824	/*
 825	 * Stamp and write the inode buffers.
 826	 *
 827	 * Seed the new inode cluster with a random generation number. This
 828	 * prevents short-term reuse of generation numbers if a chunk is
 829	 * freed and then immediately reallocated. We use random numbers
 830	 * rather than a linear progression to prevent the next generation
 831	 * number from being easily guessable.
 832	 */
 833	error = xfs_ialloc_inode_init(args.mp, tp, NULL, newlen, pag->pag_agno,
 834			args.agbno, args.len, get_random_u32());
 835
 836	if (error)
 837		return error;
 838	/*
 839	 * Convert the results.
 840	 */
 841	newino = XFS_AGB_TO_AGINO(args.mp, args.agbno);
 842
 843	if (xfs_inobt_issparse(~allocmask)) {
 844		/*
 845		 * We've allocated a sparse chunk. Align the startino and mask.
 846		 */
 847		xfs_align_sparse_ino(args.mp, &newino, &allocmask);
 848
 849		rec.ir_startino = newino;
 850		rec.ir_holemask = ~allocmask;
 851		rec.ir_count = newlen;
 852		rec.ir_freecount = newlen;
 853		rec.ir_free = XFS_INOBT_ALL_FREE;
 854
 855		/*
 856		 * Insert the sparse record into the inobt and allow for a merge
 857		 * if necessary. If a merge does occur, rec is updated to the
 858		 * merged record.
 859		 */
 860		error = xfs_inobt_insert_sprec(pag, tp, agbp,
 861				XFS_BTNUM_INO, &rec, true);
 862		if (error == -EFSCORRUPTED) {
 863			xfs_alert(args.mp,
 864	"invalid sparse inode record: ino 0x%llx holemask 0x%x count %u",
 865				  XFS_AGINO_TO_INO(args.mp, pag->pag_agno,
 866						   rec.ir_startino),
 867				  rec.ir_holemask, rec.ir_count);
 868			xfs_force_shutdown(args.mp, SHUTDOWN_CORRUPT_INCORE);
 869		}
 870		if (error)
 871			return error;
 872
 873		/*
 874		 * We can't merge the part we've just allocated as for the inobt
 875		 * due to finobt semantics. The original record may or may not
 876		 * exist independent of whether physical inodes exist in this
 877		 * sparse chunk.
 878		 *
 879		 * We must update the finobt record based on the inobt record.
 880		 * rec contains the fully merged and up to date inobt record
 881		 * from the previous call. Set merge false to replace any
 882		 * existing record with this one.
 883		 */
 884		if (xfs_has_finobt(args.mp)) {
 885			error = xfs_inobt_insert_sprec(pag, tp, agbp,
 886				       XFS_BTNUM_FINO, &rec, false);
 887			if (error)
 888				return error;
 889		}
 890	} else {
 891		/* full chunk - insert new records to both btrees */
 892		error = xfs_inobt_insert(pag, tp, agbp, newino, newlen,
 893					 XFS_BTNUM_INO);
 894		if (error)
 895			return error;
 896
 897		if (xfs_has_finobt(args.mp)) {
 898			error = xfs_inobt_insert(pag, tp, agbp, newino,
 899						 newlen, XFS_BTNUM_FINO);
 900			if (error)
 901				return error;
 902		}
 903	}
 904
 905	/*
 906	 * Update AGI counts and newino.
 907	 */
 908	be32_add_cpu(&agi->agi_count, newlen);
 909	be32_add_cpu(&agi->agi_freecount, newlen);
 910	pag->pagi_freecount += newlen;
 911	pag->pagi_count += newlen;
 912	agi->agi_newino = cpu_to_be32(newino);
 913
 914	/*
 915	 * Log allocation group header fields
 916	 */
 917	xfs_ialloc_log_agi(tp, agbp,
 918		XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
 919	/*
 920	 * Modify/log superblock values for inode count and inode free count.
 921	 */
 922	xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
 923	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
 924	return 0;
 925}
 926
 927/*
 928 * Try to retrieve the next record to the left/right from the current one.
 929 */
 930STATIC int
 931xfs_ialloc_next_rec(
 932	struct xfs_btree_cur	*cur,
 933	xfs_inobt_rec_incore_t	*rec,
 934	int			*done,
 935	int			left)
 936{
 937	int                     error;
 938	int			i;
 939
 940	if (left)
 941		error = xfs_btree_decrement(cur, 0, &i);
 942	else
 943		error = xfs_btree_increment(cur, 0, &i);
 944
 945	if (error)
 946		return error;
 947	*done = !i;
 948	if (i) {
 949		error = xfs_inobt_get_rec(cur, rec, &i);
 950		if (error)
 951			return error;
 952		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 953			return -EFSCORRUPTED;
 954	}
 955
 956	return 0;
 957}
 958
 959STATIC int
 960xfs_ialloc_get_rec(
 961	struct xfs_btree_cur	*cur,
 962	xfs_agino_t		agino,
 963	xfs_inobt_rec_incore_t	*rec,
 964	int			*done)
 965{
 966	int                     error;
 967	int			i;
 968
 969	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
 970	if (error)
 971		return error;
 972	*done = !i;
 973	if (i) {
 974		error = xfs_inobt_get_rec(cur, rec, &i);
 975		if (error)
 976			return error;
 977		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 978			return -EFSCORRUPTED;
 979	}
 980
 981	return 0;
 982}
 983
 984/*
 985 * Return the offset of the first free inode in the record. If the inode chunk
 986 * is sparsely allocated, we convert the record holemask to inode granularity
 987 * and mask off the unallocated regions from the inode free mask.
 988 */
 989STATIC int
 990xfs_inobt_first_free_inode(
 991	struct xfs_inobt_rec_incore	*rec)
 992{
 993	xfs_inofree_t			realfree;
 994
 995	/* if there are no holes, return the first available offset */
 996	if (!xfs_inobt_issparse(rec->ir_holemask))
 997		return xfs_lowbit64(rec->ir_free);
 998
 999	realfree = xfs_inobt_irec_to_allocmask(rec);
1000	realfree &= rec->ir_free;
1001
1002	return xfs_lowbit64(realfree);
1003}
1004
1005/*
1006 * Allocate an inode using the inobt-only algorithm.
1007 */
1008STATIC int
1009xfs_dialloc_ag_inobt(
1010	struct xfs_perag	*pag,
1011	struct xfs_trans	*tp,
1012	struct xfs_buf		*agbp,
 
1013	xfs_ino_t		parent,
1014	xfs_ino_t		*inop)
1015{
1016	struct xfs_mount	*mp = tp->t_mountp;
1017	struct xfs_agi		*agi = agbp->b_addr;
1018	xfs_agnumber_t		pagno = XFS_INO_TO_AGNO(mp, parent);
1019	xfs_agino_t		pagino = XFS_INO_TO_AGINO(mp, parent);
1020	struct xfs_btree_cur	*cur, *tcur;
1021	struct xfs_inobt_rec_incore rec, trec;
1022	xfs_ino_t		ino;
1023	int			error;
1024	int			offset;
1025	int			i, j;
1026	int			searchdistance = 10;
1027
1028	ASSERT(xfs_perag_initialised_agi(pag));
1029	ASSERT(xfs_perag_allows_inodes(pag));
1030	ASSERT(pag->pagi_freecount > 0);
1031
1032 restart_pagno:
1033	cur = xfs_inobt_init_cursor(pag, tp, agbp, XFS_BTNUM_INO);
1034	/*
1035	 * If pagino is 0 (this is the root inode allocation) use newino.
1036	 * This must work because we've just allocated some.
1037	 */
1038	if (!pagino)
1039		pagino = be32_to_cpu(agi->agi_newino);
1040
1041	error = xfs_check_agi_freecount(cur);
1042	if (error)
1043		goto error0;
1044
1045	/*
1046	 * If in the same AG as the parent, try to get near the parent.
1047	 */
1048	if (pagno == pag->pag_agno) {
1049		int		doneleft;	/* done, to the left */
1050		int		doneright;	/* done, to the right */
1051
1052		error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
1053		if (error)
1054			goto error0;
1055		if (XFS_IS_CORRUPT(mp, i != 1)) {
1056			error = -EFSCORRUPTED;
1057			goto error0;
1058		}
1059
1060		error = xfs_inobt_get_rec(cur, &rec, &j);
1061		if (error)
1062			goto error0;
1063		if (XFS_IS_CORRUPT(mp, j != 1)) {
1064			error = -EFSCORRUPTED;
1065			goto error0;
1066		}
1067
1068		if (rec.ir_freecount > 0) {
1069			/*
1070			 * Found a free inode in the same chunk
1071			 * as the parent, done.
1072			 */
1073			goto alloc_inode;
1074		}
1075
1076
1077		/*
1078		 * In the same AG as parent, but parent's chunk is full.
1079		 */
1080
1081		/* duplicate the cursor, search left & right simultaneously */
1082		error = xfs_btree_dup_cursor(cur, &tcur);
1083		if (error)
1084			goto error0;
1085
1086		/*
1087		 * Skip to last blocks looked up if same parent inode.
1088		 */
1089		if (pagino != NULLAGINO &&
1090		    pag->pagl_pagino == pagino &&
1091		    pag->pagl_leftrec != NULLAGINO &&
1092		    pag->pagl_rightrec != NULLAGINO) {
1093			error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
1094						   &trec, &doneleft);
1095			if (error)
1096				goto error1;
1097
1098			error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
1099						   &rec, &doneright);
1100			if (error)
1101				goto error1;
1102		} else {
1103			/* search left with tcur, back up 1 record */
1104			error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
1105			if (error)
1106				goto error1;
1107
1108			/* search right with cur, go forward 1 record. */
1109			error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
1110			if (error)
1111				goto error1;
1112		}
1113
1114		/*
1115		 * Loop until we find an inode chunk with a free inode.
1116		 */
1117		while (--searchdistance > 0 && (!doneleft || !doneright)) {
1118			int	useleft;  /* using left inode chunk this time */
1119
1120			/* figure out the closer block if both are valid. */
1121			if (!doneleft && !doneright) {
1122				useleft = pagino -
1123				 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
1124				  rec.ir_startino - pagino;
1125			} else {
1126				useleft = !doneleft;
1127			}
1128
1129			/* free inodes to the left? */
1130			if (useleft && trec.ir_freecount) {
1131				xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1132				cur = tcur;
1133
1134				pag->pagl_leftrec = trec.ir_startino;
1135				pag->pagl_rightrec = rec.ir_startino;
1136				pag->pagl_pagino = pagino;
1137				rec = trec;
1138				goto alloc_inode;
1139			}
1140
1141			/* free inodes to the right? */
1142			if (!useleft && rec.ir_freecount) {
1143				xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1144
1145				pag->pagl_leftrec = trec.ir_startino;
1146				pag->pagl_rightrec = rec.ir_startino;
1147				pag->pagl_pagino = pagino;
1148				goto alloc_inode;
1149			}
1150
1151			/* get next record to check */
1152			if (useleft) {
1153				error = xfs_ialloc_next_rec(tcur, &trec,
1154								 &doneleft, 1);
1155			} else {
1156				error = xfs_ialloc_next_rec(cur, &rec,
1157								 &doneright, 0);
1158			}
1159			if (error)
1160				goto error1;
1161		}
1162
1163		if (searchdistance <= 0) {
1164			/*
1165			 * Not in range - save last search
1166			 * location and allocate a new inode
1167			 */
1168			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1169			pag->pagl_leftrec = trec.ir_startino;
1170			pag->pagl_rightrec = rec.ir_startino;
1171			pag->pagl_pagino = pagino;
1172
1173		} else {
1174			/*
1175			 * We've reached the end of the btree. because
1176			 * we are only searching a small chunk of the
1177			 * btree each search, there is obviously free
1178			 * inodes closer to the parent inode than we
1179			 * are now. restart the search again.
1180			 */
1181			pag->pagl_pagino = NULLAGINO;
1182			pag->pagl_leftrec = NULLAGINO;
1183			pag->pagl_rightrec = NULLAGINO;
1184			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1185			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1186			goto restart_pagno;
1187		}
1188	}
1189
1190	/*
1191	 * In a different AG from the parent.
1192	 * See if the most recently allocated block has any free.
1193	 */
1194	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1195		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1196					 XFS_LOOKUP_EQ, &i);
1197		if (error)
1198			goto error0;
1199
1200		if (i == 1) {
1201			error = xfs_inobt_get_rec(cur, &rec, &j);
1202			if (error)
1203				goto error0;
1204
1205			if (j == 1 && rec.ir_freecount > 0) {
1206				/*
1207				 * The last chunk allocated in the group
1208				 * still has a free inode.
1209				 */
1210				goto alloc_inode;
1211			}
1212		}
1213	}
1214
1215	/*
1216	 * None left in the last group, search the whole AG
1217	 */
1218	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1219	if (error)
1220		goto error0;
1221	if (XFS_IS_CORRUPT(mp, i != 1)) {
1222		error = -EFSCORRUPTED;
1223		goto error0;
1224	}
1225
1226	for (;;) {
1227		error = xfs_inobt_get_rec(cur, &rec, &i);
1228		if (error)
1229			goto error0;
1230		if (XFS_IS_CORRUPT(mp, i != 1)) {
1231			error = -EFSCORRUPTED;
1232			goto error0;
1233		}
1234		if (rec.ir_freecount > 0)
1235			break;
1236		error = xfs_btree_increment(cur, 0, &i);
1237		if (error)
1238			goto error0;
1239		if (XFS_IS_CORRUPT(mp, i != 1)) {
1240			error = -EFSCORRUPTED;
1241			goto error0;
1242		}
1243	}
1244
1245alloc_inode:
1246	offset = xfs_inobt_first_free_inode(&rec);
1247	ASSERT(offset >= 0);
1248	ASSERT(offset < XFS_INODES_PER_CHUNK);
1249	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1250				   XFS_INODES_PER_CHUNK) == 0);
1251	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1252	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1253	rec.ir_freecount--;
1254	error = xfs_inobt_update(cur, &rec);
1255	if (error)
1256		goto error0;
1257	be32_add_cpu(&agi->agi_freecount, -1);
1258	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1259	pag->pagi_freecount--;
1260
1261	error = xfs_check_agi_freecount(cur);
1262	if (error)
1263		goto error0;
1264
1265	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1266	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1267	*inop = ino;
1268	return 0;
1269error1:
1270	xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1271error0:
1272	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1273	return error;
1274}
1275
1276/*
1277 * Use the free inode btree to allocate an inode based on distance from the
1278 * parent. Note that the provided cursor may be deleted and replaced.
1279 */
1280STATIC int
1281xfs_dialloc_ag_finobt_near(
1282	xfs_agino_t			pagino,
1283	struct xfs_btree_cur		**ocur,
1284	struct xfs_inobt_rec_incore	*rec)
1285{
1286	struct xfs_btree_cur		*lcur = *ocur;	/* left search cursor */
1287	struct xfs_btree_cur		*rcur;	/* right search cursor */
1288	struct xfs_inobt_rec_incore	rrec;
1289	int				error;
1290	int				i, j;
1291
1292	error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
1293	if (error)
1294		return error;
1295
1296	if (i == 1) {
1297		error = xfs_inobt_get_rec(lcur, rec, &i);
1298		if (error)
1299			return error;
1300		if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1))
1301			return -EFSCORRUPTED;
1302
1303		/*
1304		 * See if we've landed in the parent inode record. The finobt
1305		 * only tracks chunks with at least one free inode, so record
1306		 * existence is enough.
1307		 */
1308		if (pagino >= rec->ir_startino &&
1309		    pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
1310			return 0;
1311	}
1312
1313	error = xfs_btree_dup_cursor(lcur, &rcur);
1314	if (error)
1315		return error;
1316
1317	error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
1318	if (error)
1319		goto error_rcur;
1320	if (j == 1) {
1321		error = xfs_inobt_get_rec(rcur, &rrec, &j);
1322		if (error)
1323			goto error_rcur;
1324		if (XFS_IS_CORRUPT(lcur->bc_mp, j != 1)) {
1325			error = -EFSCORRUPTED;
1326			goto error_rcur;
1327		}
1328	}
1329
1330	if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1 && j != 1)) {
1331		error = -EFSCORRUPTED;
1332		goto error_rcur;
1333	}
1334	if (i == 1 && j == 1) {
1335		/*
1336		 * Both the left and right records are valid. Choose the closer
1337		 * inode chunk to the target.
1338		 */
1339		if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
1340		    (rrec.ir_startino - pagino)) {
1341			*rec = rrec;
1342			xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1343			*ocur = rcur;
1344		} else {
1345			xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1346		}
1347	} else if (j == 1) {
1348		/* only the right record is valid */
1349		*rec = rrec;
1350		xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1351		*ocur = rcur;
1352	} else if (i == 1) {
1353		/* only the left record is valid */
1354		xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1355	}
1356
1357	return 0;
1358
1359error_rcur:
1360	xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
1361	return error;
1362}
1363
1364/*
1365 * Use the free inode btree to find a free inode based on a newino hint. If
1366 * the hint is NULL, find the first free inode in the AG.
1367 */
1368STATIC int
1369xfs_dialloc_ag_finobt_newino(
1370	struct xfs_agi			*agi,
1371	struct xfs_btree_cur		*cur,
1372	struct xfs_inobt_rec_incore	*rec)
1373{
1374	int error;
1375	int i;
1376
1377	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1378		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1379					 XFS_LOOKUP_EQ, &i);
1380		if (error)
1381			return error;
1382		if (i == 1) {
1383			error = xfs_inobt_get_rec(cur, rec, &i);
1384			if (error)
1385				return error;
1386			if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1387				return -EFSCORRUPTED;
1388			return 0;
1389		}
1390	}
1391
1392	/*
1393	 * Find the first inode available in the AG.
1394	 */
1395	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1396	if (error)
1397		return error;
1398	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1399		return -EFSCORRUPTED;
1400
1401	error = xfs_inobt_get_rec(cur, rec, &i);
1402	if (error)
1403		return error;
1404	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1405		return -EFSCORRUPTED;
1406
1407	return 0;
1408}
1409
1410/*
1411 * Update the inobt based on a modification made to the finobt. Also ensure that
1412 * the records from both trees are equivalent post-modification.
1413 */
1414STATIC int
1415xfs_dialloc_ag_update_inobt(
1416	struct xfs_btree_cur		*cur,	/* inobt cursor */
1417	struct xfs_inobt_rec_incore	*frec,	/* finobt record */
1418	int				offset) /* inode offset */
1419{
1420	struct xfs_inobt_rec_incore	rec;
1421	int				error;
1422	int				i;
1423
1424	error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
1425	if (error)
1426		return error;
1427	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1428		return -EFSCORRUPTED;
1429
1430	error = xfs_inobt_get_rec(cur, &rec, &i);
1431	if (error)
1432		return error;
1433	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1434		return -EFSCORRUPTED;
1435	ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
1436				   XFS_INODES_PER_CHUNK) == 0);
1437
1438	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1439	rec.ir_freecount--;
1440
1441	if (XFS_IS_CORRUPT(cur->bc_mp,
1442			   rec.ir_free != frec->ir_free ||
1443			   rec.ir_freecount != frec->ir_freecount))
1444		return -EFSCORRUPTED;
1445
1446	return xfs_inobt_update(cur, &rec);
1447}
1448
1449/*
1450 * Allocate an inode using the free inode btree, if available. Otherwise, fall
1451 * back to the inobt search algorithm.
1452 *
1453 * The caller selected an AG for us, and made sure that free inodes are
1454 * available.
1455 */
1456static int
1457xfs_dialloc_ag(
1458	struct xfs_perag	*pag,
1459	struct xfs_trans	*tp,
1460	struct xfs_buf		*agbp,
 
1461	xfs_ino_t		parent,
1462	xfs_ino_t		*inop)
1463{
1464	struct xfs_mount		*mp = tp->t_mountp;
1465	struct xfs_agi			*agi = agbp->b_addr;
1466	xfs_agnumber_t			pagno = XFS_INO_TO_AGNO(mp, parent);
1467	xfs_agino_t			pagino = XFS_INO_TO_AGINO(mp, parent);
1468	struct xfs_btree_cur		*cur;	/* finobt cursor */
1469	struct xfs_btree_cur		*icur;	/* inobt cursor */
1470	struct xfs_inobt_rec_incore	rec;
1471	xfs_ino_t			ino;
1472	int				error;
1473	int				offset;
1474	int				i;
1475
1476	if (!xfs_has_finobt(mp))
1477		return xfs_dialloc_ag_inobt(pag, tp, agbp, parent, inop);
1478
1479	/*
1480	 * If pagino is 0 (this is the root inode allocation) use newino.
1481	 * This must work because we've just allocated some.
1482	 */
1483	if (!pagino)
1484		pagino = be32_to_cpu(agi->agi_newino);
1485
1486	cur = xfs_inobt_init_cursor(pag, tp, agbp, XFS_BTNUM_FINO);
1487
1488	error = xfs_check_agi_freecount(cur);
1489	if (error)
1490		goto error_cur;
1491
1492	/*
1493	 * The search algorithm depends on whether we're in the same AG as the
1494	 * parent. If so, find the closest available inode to the parent. If
1495	 * not, consider the agi hint or find the first free inode in the AG.
1496	 */
1497	if (pag->pag_agno == pagno)
1498		error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
1499	else
1500		error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
1501	if (error)
1502		goto error_cur;
1503
1504	offset = xfs_inobt_first_free_inode(&rec);
1505	ASSERT(offset >= 0);
1506	ASSERT(offset < XFS_INODES_PER_CHUNK);
1507	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1508				   XFS_INODES_PER_CHUNK) == 0);
1509	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1510
1511	/*
1512	 * Modify or remove the finobt record.
1513	 */
1514	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1515	rec.ir_freecount--;
1516	if (rec.ir_freecount)
1517		error = xfs_inobt_update(cur, &rec);
1518	else
1519		error = xfs_btree_delete(cur, &i);
1520	if (error)
1521		goto error_cur;
1522
1523	/*
1524	 * The finobt has now been updated appropriately. We haven't updated the
1525	 * agi and superblock yet, so we can create an inobt cursor and validate
1526	 * the original freecount. If all is well, make the equivalent update to
1527	 * the inobt using the finobt record and offset information.
1528	 */
1529	icur = xfs_inobt_init_cursor(pag, tp, agbp, XFS_BTNUM_INO);
1530
1531	error = xfs_check_agi_freecount(icur);
1532	if (error)
1533		goto error_icur;
1534
1535	error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
1536	if (error)
1537		goto error_icur;
1538
1539	/*
1540	 * Both trees have now been updated. We must update the perag and
1541	 * superblock before we can check the freecount for each btree.
1542	 */
1543	be32_add_cpu(&agi->agi_freecount, -1);
1544	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1545	pag->pagi_freecount--;
1546
1547	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1548
1549	error = xfs_check_agi_freecount(icur);
1550	if (error)
1551		goto error_icur;
1552	error = xfs_check_agi_freecount(cur);
1553	if (error)
1554		goto error_icur;
1555
1556	xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
1557	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1558	*inop = ino;
1559	return 0;
1560
1561error_icur:
1562	xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
1563error_cur:
1564	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1565	return error;
1566}
1567
1568static int
1569xfs_dialloc_roll(
1570	struct xfs_trans	**tpp,
1571	struct xfs_buf		*agibp)
1572{
1573	struct xfs_trans	*tp = *tpp;
1574	struct xfs_dquot_acct	*dqinfo;
1575	int			error;
1576
1577	/*
1578	 * Hold to on to the agibp across the commit so no other allocation can
1579	 * come in and take the free inodes we just allocated for our caller.
1580	 */
1581	xfs_trans_bhold(tp, agibp);
1582
1583	/*
1584	 * We want the quota changes to be associated with the next transaction,
1585	 * NOT this one. So, detach the dqinfo from this and attach it to the
1586	 * next transaction.
1587	 */
1588	dqinfo = tp->t_dqinfo;
1589	tp->t_dqinfo = NULL;
1590
1591	error = xfs_trans_roll(&tp);
1592
1593	/* Re-attach the quota info that we detached from prev trx. */
1594	tp->t_dqinfo = dqinfo;
1595
1596	/*
1597	 * Join the buffer even on commit error so that the buffer is released
1598	 * when the caller cancels the transaction and doesn't have to handle
1599	 * this error case specially.
1600	 */
1601	xfs_trans_bjoin(tp, agibp);
1602	*tpp = tp;
1603	return error;
1604}
1605
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1606static bool
1607xfs_dialloc_good_ag(
1608	struct xfs_perag	*pag,
1609	struct xfs_trans	*tp,
 
1610	umode_t			mode,
1611	int			flags,
1612	bool			ok_alloc)
1613{
1614	struct xfs_mount	*mp = tp->t_mountp;
1615	xfs_extlen_t		ineed;
1616	xfs_extlen_t		longest = 0;
1617	int			needspace;
1618	int			error;
1619
1620	if (!pag)
1621		return false;
1622	if (!xfs_perag_allows_inodes(pag))
1623		return false;
1624
1625	if (!xfs_perag_initialised_agi(pag)) {
1626		error = xfs_ialloc_read_agi(pag, tp, NULL);
1627		if (error)
1628			return false;
1629	}
1630
1631	if (pag->pagi_freecount)
1632		return true;
1633	if (!ok_alloc)
1634		return false;
1635
1636	if (!xfs_perag_initialised_agf(pag)) {
1637		error = xfs_alloc_read_agf(pag, tp, flags, NULL);
1638		if (error)
1639			return false;
1640	}
1641
1642	/*
1643	 * Check that there is enough free space for the file plus a chunk of
1644	 * inodes if we need to allocate some. If this is the first pass across
1645	 * the AGs, take into account the potential space needed for alignment
1646	 * of inode chunks when checking the longest contiguous free space in
1647	 * the AG - this prevents us from getting ENOSPC because we have free
1648	 * space larger than ialloc_blks but alignment constraints prevent us
1649	 * from using it.
1650	 *
1651	 * If we can't find an AG with space for full alignment slack to be
1652	 * taken into account, we must be near ENOSPC in all AGs.  Hence we
1653	 * don't include alignment for the second pass and so if we fail
1654	 * allocation due to alignment issues then it is most likely a real
1655	 * ENOSPC condition.
1656	 *
1657	 * XXX(dgc): this calculation is now bogus thanks to the per-ag
1658	 * reservations that xfs_alloc_fix_freelist() now does via
1659	 * xfs_alloc_space_available(). When the AG fills up, pagf_freeblks will
1660	 * be more than large enough for the check below to succeed, but
1661	 * xfs_alloc_space_available() will fail because of the non-zero
1662	 * metadata reservation and hence we won't actually be able to allocate
1663	 * more inodes in this AG. We do soooo much unnecessary work near ENOSPC
1664	 * because of this.
1665	 */
1666	ineed = M_IGEO(mp)->ialloc_min_blks;
1667	if (flags && ineed > 1)
1668		ineed += M_IGEO(mp)->cluster_align;
1669	longest = pag->pagf_longest;
1670	if (!longest)
1671		longest = pag->pagf_flcount > 0;
1672	needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
1673
1674	if (pag->pagf_freeblks < needspace + ineed || longest < ineed)
1675		return false;
1676	return true;
1677}
1678
1679static int
1680xfs_dialloc_try_ag(
1681	struct xfs_perag	*pag,
1682	struct xfs_trans	**tpp,
 
1683	xfs_ino_t		parent,
1684	xfs_ino_t		*new_ino,
1685	bool			ok_alloc)
1686{
1687	struct xfs_buf		*agbp;
1688	xfs_ino_t		ino;
1689	int			error;
1690
1691	/*
1692	 * Then read in the AGI buffer and recheck with the AGI buffer
1693	 * lock held.
1694	 */
1695	error = xfs_ialloc_read_agi(pag, *tpp, &agbp);
1696	if (error)
1697		return error;
1698
1699	if (!pag->pagi_freecount) {
1700		if (!ok_alloc) {
1701			error = -EAGAIN;
1702			goto out_release;
1703		}
1704
1705		error = xfs_ialloc_ag_alloc(pag, *tpp, agbp);
1706		if (error < 0)
1707			goto out_release;
1708
1709		/*
1710		 * We successfully allocated space for an inode cluster in this
1711		 * AG.  Roll the transaction so that we can allocate one of the
1712		 * new inodes.
1713		 */
1714		ASSERT(pag->pagi_freecount > 0);
1715		error = xfs_dialloc_roll(tpp, agbp);
1716		if (error)
1717			goto out_release;
1718	}
1719
1720	/* Allocate an inode in the found AG */
1721	error = xfs_dialloc_ag(pag, *tpp, agbp, parent, &ino);
1722	if (!error)
1723		*new_ino = ino;
1724	return error;
1725
1726out_release:
1727	xfs_trans_brelse(*tpp, agbp);
1728	return error;
1729}
1730
1731/*
1732 * Allocate an on-disk inode.
1733 *
1734 * Mode is used to tell whether the new inode is a directory and hence where to
1735 * locate it. The on-disk inode that is allocated will be returned in @new_ino
1736 * on success, otherwise an error will be set to indicate the failure (e.g.
1737 * -ENOSPC).
1738 */
1739int
1740xfs_dialloc(
1741	struct xfs_trans	**tpp,
1742	xfs_ino_t		parent,
1743	umode_t			mode,
1744	xfs_ino_t		*new_ino)
1745{
1746	struct xfs_mount	*mp = (*tpp)->t_mountp;
1747	xfs_agnumber_t		agno;
1748	int			error = 0;
1749	xfs_agnumber_t		start_agno;
1750	struct xfs_perag	*pag;
1751	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
1752	bool			ok_alloc = true;
1753	bool			low_space = false;
1754	int			flags;
1755	xfs_ino_t		ino = NULLFSINO;
1756
1757	/*
1758	 * Directories, symlinks, and regular files frequently allocate at least
1759	 * one block, so factor that potential expansion when we examine whether
1760	 * an AG has enough space for file creation.
1761	 */
1762	if (S_ISDIR(mode))
1763		start_agno = (atomic_inc_return(&mp->m_agirotor) - 1) %
1764				mp->m_maxagi;
1765	else {
1766		start_agno = XFS_INO_TO_AGNO(mp, parent);
1767		if (start_agno >= mp->m_maxagi)
1768			start_agno = 0;
1769	}
1770
1771	/*
1772	 * If we have already hit the ceiling of inode blocks then clear
1773	 * ok_alloc so we scan all available agi structures for a free
1774	 * inode.
1775	 *
1776	 * Read rough value of mp->m_icount by percpu_counter_read_positive,
1777	 * which will sacrifice the preciseness but improve the performance.
1778	 */
1779	if (igeo->maxicount &&
1780	    percpu_counter_read_positive(&mp->m_icount) + igeo->ialloc_inos
1781							> igeo->maxicount) {
1782		ok_alloc = false;
1783	}
1784
1785	/*
1786	 * If we are near to ENOSPC, we want to prefer allocation from AGs that
1787	 * have free inodes in them rather than use up free space allocating new
1788	 * inode chunks. Hence we turn off allocation for the first non-blocking
1789	 * pass through the AGs if we are near ENOSPC to consume free inodes
1790	 * that we can immediately allocate, but then we allow allocation on the
1791	 * second pass if we fail to find an AG with free inodes in it.
1792	 */
1793	if (percpu_counter_read_positive(&mp->m_fdblocks) <
1794			mp->m_low_space[XFS_LOWSP_1_PCNT]) {
1795		ok_alloc = false;
1796		low_space = true;
1797	}
1798
1799	/*
1800	 * Loop until we find an allocation group that either has free inodes
1801	 * or in which we can allocate some inodes.  Iterate through the
1802	 * allocation groups upward, wrapping at the end.
1803	 */
 
1804	flags = XFS_ALLOC_FLAG_TRYLOCK;
1805retry:
1806	for_each_perag_wrap_at(mp, start_agno, mp->m_maxagi, agno, pag) {
1807		if (xfs_dialloc_good_ag(pag, *tpp, mode, flags, ok_alloc)) {
1808			error = xfs_dialloc_try_ag(pag, tpp, parent,
1809					&ino, ok_alloc);
1810			if (error != -EAGAIN)
1811				break;
1812			error = 0;
1813		}
1814
1815		if (xfs_is_shutdown(mp)) {
1816			error = -EFSCORRUPTED;
1817			break;
1818		}
1819	}
1820	if (pag)
1821		xfs_perag_rele(pag);
1822	if (error)
1823		return error;
1824	if (ino == NULLFSINO) {
1825		if (flags) {
1826			flags = 0;
1827			if (low_space)
1828				ok_alloc = true;
1829			goto retry;
1830		}
1831		return -ENOSPC;
1832	}
1833	*new_ino = ino;
1834	return 0;
 
 
 
1835}
1836
1837/*
1838 * Free the blocks of an inode chunk. We must consider that the inode chunk
1839 * might be sparse and only free the regions that are allocated as part of the
1840 * chunk.
1841 */
1842static int
1843xfs_difree_inode_chunk(
1844	struct xfs_trans		*tp,
1845	xfs_agnumber_t			agno,
1846	struct xfs_inobt_rec_incore	*rec)
1847{
1848	struct xfs_mount		*mp = tp->t_mountp;
1849	xfs_agblock_t			sagbno = XFS_AGINO_TO_AGBNO(mp,
1850							rec->ir_startino);
1851	int				startidx, endidx;
1852	int				nextbit;
1853	xfs_agblock_t			agbno;
1854	int				contigblk;
1855	DECLARE_BITMAP(holemask, XFS_INOBT_HOLEMASK_BITS);
1856
1857	if (!xfs_inobt_issparse(rec->ir_holemask)) {
1858		/* not sparse, calculate extent info directly */
1859		return xfs_free_extent_later(tp,
1860				XFS_AGB_TO_FSB(mp, agno, sagbno),
1861				M_IGEO(mp)->ialloc_blks, &XFS_RMAP_OINFO_INODES,
1862				XFS_AG_RESV_NONE, false);
1863	}
1864
1865	/* holemask is only 16-bits (fits in an unsigned long) */
1866	ASSERT(sizeof(rec->ir_holemask) <= sizeof(holemask[0]));
1867	holemask[0] = rec->ir_holemask;
1868
1869	/*
1870	 * Find contiguous ranges of zeroes (i.e., allocated regions) in the
1871	 * holemask and convert the start/end index of each range to an extent.
1872	 * We start with the start and end index both pointing at the first 0 in
1873	 * the mask.
1874	 */
1875	startidx = endidx = find_first_zero_bit(holemask,
1876						XFS_INOBT_HOLEMASK_BITS);
1877	nextbit = startidx + 1;
1878	while (startidx < XFS_INOBT_HOLEMASK_BITS) {
1879		int error;
1880
1881		nextbit = find_next_zero_bit(holemask, XFS_INOBT_HOLEMASK_BITS,
1882					     nextbit);
1883		/*
1884		 * If the next zero bit is contiguous, update the end index of
1885		 * the current range and continue.
1886		 */
1887		if (nextbit != XFS_INOBT_HOLEMASK_BITS &&
1888		    nextbit == endidx + 1) {
1889			endidx = nextbit;
1890			goto next;
1891		}
1892
1893		/*
1894		 * nextbit is not contiguous with the current end index. Convert
1895		 * the current start/end to an extent and add it to the free
1896		 * list.
1897		 */
1898		agbno = sagbno + (startidx * XFS_INODES_PER_HOLEMASK_BIT) /
1899				  mp->m_sb.sb_inopblock;
1900		contigblk = ((endidx - startidx + 1) *
1901			     XFS_INODES_PER_HOLEMASK_BIT) /
1902			    mp->m_sb.sb_inopblock;
1903
1904		ASSERT(agbno % mp->m_sb.sb_spino_align == 0);
1905		ASSERT(contigblk % mp->m_sb.sb_spino_align == 0);
1906		error = xfs_free_extent_later(tp,
1907				XFS_AGB_TO_FSB(mp, agno, agbno), contigblk,
1908				&XFS_RMAP_OINFO_INODES, XFS_AG_RESV_NONE,
1909				false);
1910		if (error)
1911			return error;
1912
1913		/* reset range to current bit and carry on... */
1914		startidx = endidx = nextbit;
1915
1916next:
1917		nextbit++;
1918	}
1919	return 0;
1920}
1921
1922STATIC int
1923xfs_difree_inobt(
1924	struct xfs_perag		*pag,
1925	struct xfs_trans		*tp,
1926	struct xfs_buf			*agbp,
 
1927	xfs_agino_t			agino,
1928	struct xfs_icluster		*xic,
1929	struct xfs_inobt_rec_incore	*orec)
1930{
1931	struct xfs_mount		*mp = pag->pag_mount;
1932	struct xfs_agi			*agi = agbp->b_addr;
1933	struct xfs_btree_cur		*cur;
1934	struct xfs_inobt_rec_incore	rec;
1935	int				ilen;
1936	int				error;
1937	int				i;
1938	int				off;
1939
1940	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1941	ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
1942
1943	/*
1944	 * Initialize the cursor.
1945	 */
1946	cur = xfs_inobt_init_cursor(pag, tp, agbp, XFS_BTNUM_INO);
1947
1948	error = xfs_check_agi_freecount(cur);
1949	if (error)
1950		goto error0;
1951
1952	/*
1953	 * Look for the entry describing this inode.
1954	 */
1955	if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1956		xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1957			__func__, error);
1958		goto error0;
1959	}
1960	if (XFS_IS_CORRUPT(mp, i != 1)) {
1961		error = -EFSCORRUPTED;
1962		goto error0;
1963	}
1964	error = xfs_inobt_get_rec(cur, &rec, &i);
1965	if (error) {
1966		xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1967			__func__, error);
1968		goto error0;
1969	}
1970	if (XFS_IS_CORRUPT(mp, i != 1)) {
1971		error = -EFSCORRUPTED;
1972		goto error0;
1973	}
1974	/*
1975	 * Get the offset in the inode chunk.
1976	 */
1977	off = agino - rec.ir_startino;
1978	ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1979	ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1980	/*
1981	 * Mark the inode free & increment the count.
1982	 */
1983	rec.ir_free |= XFS_INOBT_MASK(off);
1984	rec.ir_freecount++;
1985
1986	/*
1987	 * When an inode chunk is free, it becomes eligible for removal. Don't
1988	 * remove the chunk if the block size is large enough for multiple inode
1989	 * chunks (that might not be free).
1990	 */
1991	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
 
1992	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
 
 
1993		xic->deleted = true;
1994		xic->first_ino = XFS_AGINO_TO_INO(mp, pag->pag_agno,
1995				rec.ir_startino);
1996		xic->alloc = xfs_inobt_irec_to_allocmask(&rec);
1997
1998		/*
1999		 * Remove the inode cluster from the AGI B+Tree, adjust the
2000		 * AGI and Superblock inode counts, and mark the disk space
2001		 * to be freed when the transaction is committed.
2002		 */
2003		ilen = rec.ir_freecount;
2004		be32_add_cpu(&agi->agi_count, -ilen);
2005		be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
2006		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
2007		pag->pagi_freecount -= ilen - 1;
2008		pag->pagi_count -= ilen;
2009		xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
2010		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
2011
2012		if ((error = xfs_btree_delete(cur, &i))) {
2013			xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
2014				__func__, error);
2015			goto error0;
2016		}
2017
2018		error = xfs_difree_inode_chunk(tp, pag->pag_agno, &rec);
2019		if (error)
2020			goto error0;
2021	} else {
2022		xic->deleted = false;
2023
2024		error = xfs_inobt_update(cur, &rec);
2025		if (error) {
2026			xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
2027				__func__, error);
2028			goto error0;
2029		}
2030
2031		/*
2032		 * Change the inode free counts and log the ag/sb changes.
2033		 */
2034		be32_add_cpu(&agi->agi_freecount, 1);
2035		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
2036		pag->pagi_freecount++;
2037		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
2038	}
2039
2040	error = xfs_check_agi_freecount(cur);
2041	if (error)
2042		goto error0;
2043
2044	*orec = rec;
2045	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2046	return 0;
2047
2048error0:
2049	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2050	return error;
2051}
2052
2053/*
2054 * Free an inode in the free inode btree.
2055 */
2056STATIC int
2057xfs_difree_finobt(
2058	struct xfs_perag		*pag,
2059	struct xfs_trans		*tp,
2060	struct xfs_buf			*agbp,
 
2061	xfs_agino_t			agino,
2062	struct xfs_inobt_rec_incore	*ibtrec) /* inobt record */
2063{
2064	struct xfs_mount		*mp = pag->pag_mount;
2065	struct xfs_btree_cur		*cur;
2066	struct xfs_inobt_rec_incore	rec;
2067	int				offset = agino - ibtrec->ir_startino;
2068	int				error;
2069	int				i;
2070
2071	cur = xfs_inobt_init_cursor(pag, tp, agbp, XFS_BTNUM_FINO);
2072
2073	error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
2074	if (error)
2075		goto error;
2076	if (i == 0) {
2077		/*
2078		 * If the record does not exist in the finobt, we must have just
2079		 * freed an inode in a previously fully allocated chunk. If not,
2080		 * something is out of sync.
2081		 */
2082		if (XFS_IS_CORRUPT(mp, ibtrec->ir_freecount != 1)) {
2083			error = -EFSCORRUPTED;
2084			goto error;
2085		}
2086
2087		error = xfs_inobt_insert_rec(cur, ibtrec->ir_holemask,
2088					     ibtrec->ir_count,
2089					     ibtrec->ir_freecount,
2090					     ibtrec->ir_free, &i);
2091		if (error)
2092			goto error;
2093		ASSERT(i == 1);
2094
2095		goto out;
2096	}
2097
2098	/*
2099	 * Read and update the existing record. We could just copy the ibtrec
2100	 * across here, but that would defeat the purpose of having redundant
2101	 * metadata. By making the modifications independently, we can catch
2102	 * corruptions that we wouldn't see if we just copied from one record
2103	 * to another.
2104	 */
2105	error = xfs_inobt_get_rec(cur, &rec, &i);
2106	if (error)
2107		goto error;
2108	if (XFS_IS_CORRUPT(mp, i != 1)) {
2109		error = -EFSCORRUPTED;
2110		goto error;
2111	}
2112
2113	rec.ir_free |= XFS_INOBT_MASK(offset);
2114	rec.ir_freecount++;
2115
2116	if (XFS_IS_CORRUPT(mp,
2117			   rec.ir_free != ibtrec->ir_free ||
2118			   rec.ir_freecount != ibtrec->ir_freecount)) {
2119		error = -EFSCORRUPTED;
2120		goto error;
2121	}
2122
2123	/*
2124	 * The content of inobt records should always match between the inobt
2125	 * and finobt. The lifecycle of records in the finobt is different from
2126	 * the inobt in that the finobt only tracks records with at least one
2127	 * free inode. Hence, if all of the inodes are free and we aren't
2128	 * keeping inode chunks permanently on disk, remove the record.
2129	 * Otherwise, update the record with the new information.
2130	 *
2131	 * Note that we currently can't free chunks when the block size is large
2132	 * enough for multiple chunks. Leave the finobt record to remain in sync
2133	 * with the inobt.
2134	 */
2135	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
2136	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
 
2137		error = xfs_btree_delete(cur, &i);
2138		if (error)
2139			goto error;
2140		ASSERT(i == 1);
2141	} else {
2142		error = xfs_inobt_update(cur, &rec);
2143		if (error)
2144			goto error;
2145	}
2146
2147out:
2148	error = xfs_check_agi_freecount(cur);
2149	if (error)
2150		goto error;
2151
2152	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2153	return 0;
2154
2155error:
2156	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2157	return error;
2158}
2159
2160/*
2161 * Free disk inode.  Carefully avoids touching the incore inode, all
2162 * manipulations incore are the caller's responsibility.
2163 * The on-disk inode is not changed by this operation, only the
2164 * btree (free inode mask) is changed.
2165 */
2166int
2167xfs_difree(
2168	struct xfs_trans	*tp,
2169	struct xfs_perag	*pag,
2170	xfs_ino_t		inode,
2171	struct xfs_icluster	*xic)
2172{
2173	/* REFERENCED */
2174	xfs_agblock_t		agbno;	/* block number containing inode */
2175	struct xfs_buf		*agbp;	/* buffer for allocation group header */
2176	xfs_agino_t		agino;	/* allocation group inode number */
2177	int			error;	/* error return value */
2178	struct xfs_mount	*mp = tp->t_mountp;
2179	struct xfs_inobt_rec_incore rec;/* btree record */
2180
2181	/*
2182	 * Break up inode number into its components.
2183	 */
2184	if (pag->pag_agno != XFS_INO_TO_AGNO(mp, inode)) {
2185		xfs_warn(mp, "%s: agno != pag->pag_agno (%d != %d).",
2186			__func__, XFS_INO_TO_AGNO(mp, inode), pag->pag_agno);
2187		ASSERT(0);
2188		return -EINVAL;
2189	}
2190	agino = XFS_INO_TO_AGINO(mp, inode);
2191	if (inode != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino))  {
2192		xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
2193			__func__, (unsigned long long)inode,
2194			(unsigned long long)XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2195		ASSERT(0);
2196		return -EINVAL;
2197	}
2198	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2199	if (agbno >= mp->m_sb.sb_agblocks)  {
2200		xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
2201			__func__, agbno, mp->m_sb.sb_agblocks);
2202		ASSERT(0);
2203		return -EINVAL;
2204	}
2205	/*
2206	 * Get the allocation group header.
2207	 */
2208	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2209	if (error) {
2210		xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
2211			__func__, error);
2212		return error;
2213	}
2214
2215	/*
2216	 * Fix up the inode allocation btree.
2217	 */
2218	error = xfs_difree_inobt(pag, tp, agbp, agino, xic, &rec);
2219	if (error)
2220		goto error0;
2221
2222	/*
2223	 * Fix up the free inode btree.
2224	 */
2225	if (xfs_has_finobt(mp)) {
2226		error = xfs_difree_finobt(pag, tp, agbp, agino, &rec);
2227		if (error)
2228			goto error0;
2229	}
2230
2231	return 0;
2232
2233error0:
2234	return error;
2235}
2236
2237STATIC int
2238xfs_imap_lookup(
2239	struct xfs_perag	*pag,
2240	struct xfs_trans	*tp,
 
2241	xfs_agino_t		agino,
2242	xfs_agblock_t		agbno,
2243	xfs_agblock_t		*chunk_agbno,
2244	xfs_agblock_t		*offset_agbno,
2245	int			flags)
2246{
2247	struct xfs_mount	*mp = pag->pag_mount;
2248	struct xfs_inobt_rec_incore rec;
2249	struct xfs_btree_cur	*cur;
2250	struct xfs_buf		*agbp;
2251	int			error;
2252	int			i;
2253
2254	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2255	if (error) {
2256		xfs_alert(mp,
2257			"%s: xfs_ialloc_read_agi() returned error %d, agno %d",
2258			__func__, error, pag->pag_agno);
2259		return error;
2260	}
2261
2262	/*
2263	 * Lookup the inode record for the given agino. If the record cannot be
2264	 * found, then it's an invalid inode number and we should abort. Once
2265	 * we have a record, we need to ensure it contains the inode number
2266	 * we are looking up.
2267	 */
2268	cur = xfs_inobt_init_cursor(pag, tp, agbp, XFS_BTNUM_INO);
2269	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
2270	if (!error) {
2271		if (i)
2272			error = xfs_inobt_get_rec(cur, &rec, &i);
2273		if (!error && i == 0)
2274			error = -EINVAL;
2275	}
2276
2277	xfs_trans_brelse(tp, agbp);
2278	xfs_btree_del_cursor(cur, error);
2279	if (error)
2280		return error;
2281
2282	/* check that the returned record contains the required inode */
2283	if (rec.ir_startino > agino ||
2284	    rec.ir_startino + M_IGEO(mp)->ialloc_inos <= agino)
2285		return -EINVAL;
2286
2287	/* for untrusted inodes check it is allocated first */
2288	if ((flags & XFS_IGET_UNTRUSTED) &&
2289	    (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
2290		return -EINVAL;
2291
2292	*chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
2293	*offset_agbno = agbno - *chunk_agbno;
2294	return 0;
2295}
2296
2297/*
2298 * Return the location of the inode in imap, for mapping it into a buffer.
2299 */
2300int
2301xfs_imap(
2302	struct xfs_perag	*pag,
2303	struct xfs_trans	*tp,
2304	xfs_ino_t		ino,	/* inode to locate */
2305	struct xfs_imap		*imap,	/* location map structure */
2306	uint			flags)	/* flags for inode btree lookup */
2307{
2308	struct xfs_mount	*mp = pag->pag_mount;
2309	xfs_agblock_t		agbno;	/* block number of inode in the alloc group */
2310	xfs_agino_t		agino;	/* inode number within alloc group */
2311	xfs_agblock_t		chunk_agbno;	/* first block in inode chunk */
2312	xfs_agblock_t		cluster_agbno;	/* first block in inode cluster */
2313	int			error;	/* error code */
2314	int			offset;	/* index of inode in its buffer */
2315	xfs_agblock_t		offset_agbno;	/* blks from chunk start to inode */
 
2316
2317	ASSERT(ino != NULLFSINO);
2318
2319	/*
2320	 * Split up the inode number into its parts.
2321	 */
 
2322	agino = XFS_INO_TO_AGINO(mp, ino);
2323	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2324	if (agbno >= mp->m_sb.sb_agblocks ||
2325	    ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2326		error = -EINVAL;
2327#ifdef DEBUG
2328		/*
2329		 * Don't output diagnostic information for untrusted inodes
2330		 * as they can be invalid without implying corruption.
2331		 */
2332		if (flags & XFS_IGET_UNTRUSTED)
2333			return error;
 
 
 
 
 
 
2334		if (agbno >= mp->m_sb.sb_agblocks) {
2335			xfs_alert(mp,
2336		"%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
2337				__func__, (unsigned long long)agbno,
2338				(unsigned long)mp->m_sb.sb_agblocks);
2339		}
2340		if (ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2341			xfs_alert(mp,
2342		"%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
2343				__func__, ino,
2344				XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2345		}
2346		xfs_stack_trace();
2347#endif /* DEBUG */
2348		return error;
2349	}
2350
2351	/*
2352	 * For bulkstat and handle lookups, we have an untrusted inode number
2353	 * that we have to verify is valid. We cannot do this just by reading
2354	 * the inode buffer as it may have been unlinked and removed leaving
2355	 * inodes in stale state on disk. Hence we have to do a btree lookup
2356	 * in all cases where an untrusted inode number is passed.
2357	 */
2358	if (flags & XFS_IGET_UNTRUSTED) {
2359		error = xfs_imap_lookup(pag, tp, agino, agbno,
2360					&chunk_agbno, &offset_agbno, flags);
2361		if (error)
2362			return error;
2363		goto out_map;
2364	}
2365
2366	/*
2367	 * If the inode cluster size is the same as the blocksize or
2368	 * smaller we get to the buffer by simple arithmetics.
2369	 */
2370	if (M_IGEO(mp)->blocks_per_cluster == 1) {
2371		offset = XFS_INO_TO_OFFSET(mp, ino);
2372		ASSERT(offset < mp->m_sb.sb_inopblock);
2373
2374		imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, agbno);
2375		imap->im_len = XFS_FSB_TO_BB(mp, 1);
2376		imap->im_boffset = (unsigned short)(offset <<
2377							mp->m_sb.sb_inodelog);
2378		return 0;
 
2379	}
2380
2381	/*
2382	 * If the inode chunks are aligned then use simple maths to
2383	 * find the location. Otherwise we have to do a btree
2384	 * lookup to find the location.
2385	 */
2386	if (M_IGEO(mp)->inoalign_mask) {
2387		offset_agbno = agbno & M_IGEO(mp)->inoalign_mask;
2388		chunk_agbno = agbno - offset_agbno;
2389	} else {
2390		error = xfs_imap_lookup(pag, tp, agino, agbno,
2391					&chunk_agbno, &offset_agbno, flags);
2392		if (error)
2393			return error;
2394	}
2395
2396out_map:
2397	ASSERT(agbno >= chunk_agbno);
2398	cluster_agbno = chunk_agbno +
2399		((offset_agbno / M_IGEO(mp)->blocks_per_cluster) *
2400		 M_IGEO(mp)->blocks_per_cluster);
2401	offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
2402		XFS_INO_TO_OFFSET(mp, ino);
2403
2404	imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, cluster_agbno);
2405	imap->im_len = XFS_FSB_TO_BB(mp, M_IGEO(mp)->blocks_per_cluster);
2406	imap->im_boffset = (unsigned short)(offset << mp->m_sb.sb_inodelog);
2407
2408	/*
2409	 * If the inode number maps to a block outside the bounds
2410	 * of the file system then return NULL rather than calling
2411	 * read_buf and panicing when we get an error from the
2412	 * driver.
2413	 */
2414	if ((imap->im_blkno + imap->im_len) >
2415	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
2416		xfs_alert(mp,
2417	"%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
2418			__func__, (unsigned long long) imap->im_blkno,
2419			(unsigned long long) imap->im_len,
2420			XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
2421		return -EINVAL;
 
2422	}
2423	return 0;
 
 
 
 
2424}
2425
2426/*
2427 * Log specified fields for the ag hdr (inode section). The growth of the agi
2428 * structure over time requires that we interpret the buffer as two logical
2429 * regions delineated by the end of the unlinked list. This is due to the size
2430 * of the hash table and its location in the middle of the agi.
2431 *
2432 * For example, a request to log a field before agi_unlinked and a field after
2433 * agi_unlinked could cause us to log the entire hash table and use an excessive
2434 * amount of log space. To avoid this behavior, log the region up through
2435 * agi_unlinked in one call and the region after agi_unlinked through the end of
2436 * the structure in another.
2437 */
2438void
2439xfs_ialloc_log_agi(
2440	struct xfs_trans	*tp,
2441	struct xfs_buf		*bp,
2442	uint32_t		fields)
2443{
2444	int			first;		/* first byte number */
2445	int			last;		/* last byte number */
2446	static const short	offsets[] = {	/* field starting offsets */
2447					/* keep in sync with bit definitions */
2448		offsetof(xfs_agi_t, agi_magicnum),
2449		offsetof(xfs_agi_t, agi_versionnum),
2450		offsetof(xfs_agi_t, agi_seqno),
2451		offsetof(xfs_agi_t, agi_length),
2452		offsetof(xfs_agi_t, agi_count),
2453		offsetof(xfs_agi_t, agi_root),
2454		offsetof(xfs_agi_t, agi_level),
2455		offsetof(xfs_agi_t, agi_freecount),
2456		offsetof(xfs_agi_t, agi_newino),
2457		offsetof(xfs_agi_t, agi_dirino),
2458		offsetof(xfs_agi_t, agi_unlinked),
2459		offsetof(xfs_agi_t, agi_free_root),
2460		offsetof(xfs_agi_t, agi_free_level),
2461		offsetof(xfs_agi_t, agi_iblocks),
2462		sizeof(xfs_agi_t)
2463	};
2464#ifdef DEBUG
2465	struct xfs_agi		*agi = bp->b_addr;
2466
2467	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2468#endif
2469
2470	/*
2471	 * Compute byte offsets for the first and last fields in the first
2472	 * region and log the agi buffer. This only logs up through
2473	 * agi_unlinked.
2474	 */
2475	if (fields & XFS_AGI_ALL_BITS_R1) {
2476		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
2477				  &first, &last);
2478		xfs_trans_log_buf(tp, bp, first, last);
2479	}
2480
2481	/*
2482	 * Mask off the bits in the first region and calculate the first and
2483	 * last field offsets for any bits in the second region.
2484	 */
2485	fields &= ~XFS_AGI_ALL_BITS_R1;
2486	if (fields) {
2487		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
2488				  &first, &last);
2489		xfs_trans_log_buf(tp, bp, first, last);
2490	}
2491}
2492
2493static xfs_failaddr_t
2494xfs_agi_verify(
2495	struct xfs_buf		*bp)
2496{
2497	struct xfs_mount	*mp = bp->b_mount;
2498	struct xfs_agi		*agi = bp->b_addr;
2499	xfs_failaddr_t		fa;
2500	uint32_t		agi_seqno = be32_to_cpu(agi->agi_seqno);
2501	uint32_t		agi_length = be32_to_cpu(agi->agi_length);
2502	int			i;
2503
2504	if (xfs_has_crc(mp)) {
2505		if (!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid))
2506			return __this_address;
2507		if (!xfs_log_check_lsn(mp, be64_to_cpu(agi->agi_lsn)))
2508			return __this_address;
2509	}
2510
2511	/*
2512	 * Validate the magic number of the agi block.
2513	 */
2514	if (!xfs_verify_magic(bp, agi->agi_magicnum))
2515		return __this_address;
2516	if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
2517		return __this_address;
2518
2519	fa = xfs_validate_ag_length(bp, agi_seqno, agi_length);
2520	if (fa)
2521		return fa;
2522
2523	if (be32_to_cpu(agi->agi_level) < 1 ||
2524	    be32_to_cpu(agi->agi_level) > M_IGEO(mp)->inobt_maxlevels)
2525		return __this_address;
2526
2527	if (xfs_has_finobt(mp) &&
2528	    (be32_to_cpu(agi->agi_free_level) < 1 ||
2529	     be32_to_cpu(agi->agi_free_level) > M_IGEO(mp)->inobt_maxlevels))
2530		return __this_address;
2531
 
 
 
 
 
 
 
 
 
2532	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
2533		if (agi->agi_unlinked[i] == cpu_to_be32(NULLAGINO))
2534			continue;
2535		if (!xfs_verify_ino(mp, be32_to_cpu(agi->agi_unlinked[i])))
2536			return __this_address;
2537	}
2538
2539	return NULL;
2540}
2541
2542static void
2543xfs_agi_read_verify(
2544	struct xfs_buf	*bp)
2545{
2546	struct xfs_mount *mp = bp->b_mount;
2547	xfs_failaddr_t	fa;
2548
2549	if (xfs_has_crc(mp) &&
2550	    !xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
2551		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
2552	else {
2553		fa = xfs_agi_verify(bp);
2554		if (XFS_TEST_ERROR(fa, mp, XFS_ERRTAG_IALLOC_READ_AGI))
2555			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2556	}
2557}
2558
2559static void
2560xfs_agi_write_verify(
2561	struct xfs_buf	*bp)
2562{
2563	struct xfs_mount	*mp = bp->b_mount;
2564	struct xfs_buf_log_item	*bip = bp->b_log_item;
2565	struct xfs_agi		*agi = bp->b_addr;
2566	xfs_failaddr_t		fa;
2567
2568	fa = xfs_agi_verify(bp);
2569	if (fa) {
2570		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2571		return;
2572	}
2573
2574	if (!xfs_has_crc(mp))
2575		return;
2576
2577	if (bip)
2578		agi->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2579	xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
2580}
2581
2582const struct xfs_buf_ops xfs_agi_buf_ops = {
2583	.name = "xfs_agi",
2584	.magic = { cpu_to_be32(XFS_AGI_MAGIC), cpu_to_be32(XFS_AGI_MAGIC) },
2585	.verify_read = xfs_agi_read_verify,
2586	.verify_write = xfs_agi_write_verify,
2587	.verify_struct = xfs_agi_verify,
2588};
2589
2590/*
2591 * Read in the allocation group header (inode allocation section)
2592 */
2593int
2594xfs_read_agi(
2595	struct xfs_perag	*pag,
2596	struct xfs_trans	*tp,
2597	struct xfs_buf		**agibpp)
 
2598{
2599	struct xfs_mount	*mp = pag->pag_mount;
2600	int			error;
2601
2602	trace_xfs_read_agi(pag->pag_mount, pag->pag_agno);
2603
 
2604	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
2605			XFS_AG_DADDR(mp, pag->pag_agno, XFS_AGI_DADDR(mp)),
2606			XFS_FSS_TO_BB(mp, 1), 0, agibpp, &xfs_agi_buf_ops);
2607	if (error)
2608		return error;
2609	if (tp)
2610		xfs_trans_buf_set_type(tp, *agibpp, XFS_BLFT_AGI_BUF);
2611
2612	xfs_buf_set_ref(*agibpp, XFS_AGI_REF);
2613	return 0;
2614}
2615
2616/*
2617 * Read in the agi and initialise the per-ag data. If the caller supplies a
2618 * @agibpp, return the locked AGI buffer to them, otherwise release it.
2619 */
2620int
2621xfs_ialloc_read_agi(
2622	struct xfs_perag	*pag,
2623	struct xfs_trans	*tp,
2624	struct xfs_buf		**agibpp)
 
2625{
2626	struct xfs_buf		*agibp;
2627	struct xfs_agi		*agi;
2628	int			error;
2629
2630	trace_xfs_ialloc_read_agi(pag->pag_mount, pag->pag_agno);
2631
2632	error = xfs_read_agi(pag, tp, &agibp);
2633	if (error)
2634		return error;
2635
2636	agi = agibp->b_addr;
2637	if (!xfs_perag_initialised_agi(pag)) {
 
2638		pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
2639		pag->pagi_count = be32_to_cpu(agi->agi_count);
2640		set_bit(XFS_AGSTATE_AGI_INIT, &pag->pag_opstate);
2641	}
2642
2643	/*
2644	 * It's possible for these to be out of sync if
2645	 * we are in the middle of a forced shutdown.
2646	 */
2647	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
2648		xfs_is_shutdown(pag->pag_mount));
2649	if (agibpp)
2650		*agibpp = agibp;
2651	else
2652		xfs_trans_brelse(tp, agibp);
2653	return 0;
2654}
2655
2656/* How many inodes are backed by inode clusters ondisk? */
2657STATIC int
2658xfs_ialloc_count_ondisk(
2659	struct xfs_btree_cur		*cur,
2660	xfs_agino_t			low,
2661	xfs_agino_t			high,
2662	unsigned int			*allocated)
 
2663{
2664	struct xfs_inobt_rec_incore	irec;
2665	unsigned int			ret = 0;
2666	int				has_record;
2667	int				error;
2668
2669	error = xfs_inobt_lookup(cur, low, XFS_LOOKUP_LE, &has_record);
2670	if (error)
2671		return error;
 
 
 
 
2672
2673	while (has_record) {
2674		unsigned int		i, hole_idx;
 
 
 
 
 
 
 
 
 
 
 
 
2675
 
 
 
2676		error = xfs_inobt_get_rec(cur, &irec, &has_record);
2677		if (error)
2678			return error;
2679		if (irec.ir_startino > high)
2680			break;
2681
2682		for (i = 0; i < XFS_INODES_PER_CHUNK; i++) {
2683			if (irec.ir_startino + i < low)
 
 
 
2684				continue;
2685			if (irec.ir_startino + i > high)
2686				break;
2687
2688			hole_idx = i / XFS_INODES_PER_HOLEMASK_BIT;
2689			if (!(irec.ir_holemask & (1U << hole_idx)))
2690				ret++;
2691		}
2692
2693		error = xfs_btree_increment(cur, 0, &has_record);
2694		if (error)
2695			return error;
2696	}
2697
2698	*allocated = ret;
2699	return 0;
2700}
2701
2702/* Is there an inode record covering a given extent? */
2703int
2704xfs_ialloc_has_inodes_at_extent(
2705	struct xfs_btree_cur	*cur,
2706	xfs_agblock_t		bno,
2707	xfs_extlen_t		len,
2708	enum xbtree_recpacking	*outcome)
2709{
2710	xfs_agino_t		agino;
2711	xfs_agino_t		last_agino;
2712	unsigned int		allocated;
2713	int			error;
2714
2715	agino = XFS_AGB_TO_AGINO(cur->bc_mp, bno);
2716	last_agino = XFS_AGB_TO_AGINO(cur->bc_mp, bno + len) - 1;
2717
2718	error = xfs_ialloc_count_ondisk(cur, agino, last_agino, &allocated);
2719	if (error)
2720		return error;
2721
2722	if (allocated == 0)
2723		*outcome = XBTREE_RECPACKING_EMPTY;
2724	else if (allocated == last_agino - agino + 1)
2725		*outcome = XBTREE_RECPACKING_FULL;
2726	else
2727		*outcome = XBTREE_RECPACKING_SPARSE;
2728	return 0;
2729}
2730
2731struct xfs_ialloc_count_inodes {
2732	xfs_agino_t			count;
2733	xfs_agino_t			freecount;
2734};
2735
2736/* Record inode counts across all inobt records. */
2737STATIC int
2738xfs_ialloc_count_inodes_rec(
2739	struct xfs_btree_cur		*cur,
2740	const union xfs_btree_rec	*rec,
2741	void				*priv)
2742{
2743	struct xfs_inobt_rec_incore	irec;
2744	struct xfs_ialloc_count_inodes	*ci = priv;
2745	xfs_failaddr_t			fa;
2746
2747	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
2748	fa = xfs_inobt_check_irec(cur->bc_ag.pag, &irec);
2749	if (fa)
2750		return xfs_inobt_complain_bad_rec(cur, fa, &irec);
2751
2752	ci->count += irec.ir_count;
2753	ci->freecount += irec.ir_freecount;
2754
2755	return 0;
2756}
2757
2758/* Count allocated and free inodes under an inobt. */
2759int
2760xfs_ialloc_count_inodes(
2761	struct xfs_btree_cur		*cur,
2762	xfs_agino_t			*count,
2763	xfs_agino_t			*freecount)
2764{
2765	struct xfs_ialloc_count_inodes	ci = {0};
2766	int				error;
2767
2768	ASSERT(cur->bc_btnum == XFS_BTNUM_INO);
2769	error = xfs_btree_query_all(cur, xfs_ialloc_count_inodes_rec, &ci);
2770	if (error)
2771		return error;
2772
2773	*count = ci.count;
2774	*freecount = ci.freecount;
2775	return 0;
2776}
2777
2778/*
2779 * Initialize inode-related geometry information.
2780 *
2781 * Compute the inode btree min and max levels and set maxicount.
2782 *
2783 * Set the inode cluster size.  This may still be overridden by the file
2784 * system block size if it is larger than the chosen cluster size.
2785 *
2786 * For v5 filesystems, scale the cluster size with the inode size to keep a
2787 * constant ratio of inode per cluster buffer, but only if mkfs has set the
2788 * inode alignment value appropriately for larger cluster sizes.
2789 *
2790 * Then compute the inode cluster alignment information.
2791 */
2792void
2793xfs_ialloc_setup_geometry(
2794	struct xfs_mount	*mp)
2795{
2796	struct xfs_sb		*sbp = &mp->m_sb;
2797	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2798	uint64_t		icount;
2799	uint			inodes;
2800
2801	igeo->new_diflags2 = 0;
2802	if (xfs_has_bigtime(mp))
2803		igeo->new_diflags2 |= XFS_DIFLAG2_BIGTIME;
2804	if (xfs_has_large_extent_counts(mp))
2805		igeo->new_diflags2 |= XFS_DIFLAG2_NREXT64;
2806
2807	/* Compute inode btree geometry. */
2808	igeo->agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
2809	igeo->inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
2810	igeo->inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
2811	igeo->inobt_mnr[0] = igeo->inobt_mxr[0] / 2;
2812	igeo->inobt_mnr[1] = igeo->inobt_mxr[1] / 2;
2813
2814	igeo->ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK,
2815			sbp->sb_inopblock);
2816	igeo->ialloc_blks = igeo->ialloc_inos >> sbp->sb_inopblog;
2817
2818	if (sbp->sb_spino_align)
2819		igeo->ialloc_min_blks = sbp->sb_spino_align;
2820	else
2821		igeo->ialloc_min_blks = igeo->ialloc_blks;
2822
2823	/* Compute and fill in value of m_ino_geo.inobt_maxlevels. */
2824	inodes = (1LL << XFS_INO_AGINO_BITS(mp)) >> XFS_INODES_PER_CHUNK_LOG;
2825	igeo->inobt_maxlevels = xfs_btree_compute_maxlevels(igeo->inobt_mnr,
2826			inodes);
2827	ASSERT(igeo->inobt_maxlevels <= xfs_iallocbt_maxlevels_ondisk());
2828
2829	/*
2830	 * Set the maximum inode count for this filesystem, being careful not
2831	 * to use obviously garbage sb_inopblog/sb_inopblock values.  Regular
2832	 * users should never get here due to failing sb verification, but
2833	 * certain users (xfs_db) need to be usable even with corrupt metadata.
2834	 */
2835	if (sbp->sb_imax_pct && igeo->ialloc_blks) {
2836		/*
2837		 * Make sure the maximum inode count is a multiple
2838		 * of the units we allocate inodes in.
2839		 */
2840		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
2841		do_div(icount, 100);
2842		do_div(icount, igeo->ialloc_blks);
2843		igeo->maxicount = XFS_FSB_TO_INO(mp,
2844				icount * igeo->ialloc_blks);
2845	} else {
2846		igeo->maxicount = 0;
2847	}
2848
2849	/*
2850	 * Compute the desired size of an inode cluster buffer size, which
2851	 * starts at 8K and (on v5 filesystems) scales up with larger inode
2852	 * sizes.
2853	 *
2854	 * Preserve the desired inode cluster size because the sparse inodes
2855	 * feature uses that desired size (not the actual size) to compute the
2856	 * sparse inode alignment.  The mount code validates this value, so we
2857	 * cannot change the behavior.
2858	 */
2859	igeo->inode_cluster_size_raw = XFS_INODE_BIG_CLUSTER_SIZE;
2860	if (xfs_has_v3inodes(mp)) {
2861		int	new_size = igeo->inode_cluster_size_raw;
2862
2863		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
2864		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
2865			igeo->inode_cluster_size_raw = new_size;
2866	}
2867
2868	/* Calculate inode cluster ratios. */
2869	if (igeo->inode_cluster_size_raw > mp->m_sb.sb_blocksize)
2870		igeo->blocks_per_cluster = XFS_B_TO_FSBT(mp,
2871				igeo->inode_cluster_size_raw);
2872	else
2873		igeo->blocks_per_cluster = 1;
2874	igeo->inode_cluster_size = XFS_FSB_TO_B(mp, igeo->blocks_per_cluster);
2875	igeo->inodes_per_cluster = XFS_FSB_TO_INO(mp, igeo->blocks_per_cluster);
2876
2877	/* Calculate inode cluster alignment. */
2878	if (xfs_has_align(mp) &&
2879	    mp->m_sb.sb_inoalignmt >= igeo->blocks_per_cluster)
2880		igeo->cluster_align = mp->m_sb.sb_inoalignmt;
2881	else
2882		igeo->cluster_align = 1;
2883	igeo->inoalign_mask = igeo->cluster_align - 1;
2884	igeo->cluster_align_inodes = XFS_FSB_TO_INO(mp, igeo->cluster_align);
2885
2886	/*
2887	 * If we are using stripe alignment, check whether
2888	 * the stripe unit is a multiple of the inode alignment
2889	 */
2890	if (mp->m_dalign && igeo->inoalign_mask &&
2891	    !(mp->m_dalign & igeo->inoalign_mask))
2892		igeo->ialloc_align = mp->m_dalign;
2893	else
2894		igeo->ialloc_align = 0;
2895}
2896
2897/* Compute the location of the root directory inode that is laid out by mkfs. */
2898xfs_ino_t
2899xfs_ialloc_calc_rootino(
2900	struct xfs_mount	*mp,
2901	int			sunit)
2902{
2903	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2904	xfs_agblock_t		first_bno;
2905
2906	/*
2907	 * Pre-calculate the geometry of AG 0.  We know what it looks like
2908	 * because libxfs knows how to create allocation groups now.
2909	 *
2910	 * first_bno is the first block in which mkfs could possibly have
2911	 * allocated the root directory inode, once we factor in the metadata
2912	 * that mkfs formats before it.  Namely, the four AG headers...
2913	 */
2914	first_bno = howmany(4 * mp->m_sb.sb_sectsize, mp->m_sb.sb_blocksize);
2915
2916	/* ...the two free space btree roots... */
2917	first_bno += 2;
2918
2919	/* ...the inode btree root... */
2920	first_bno += 1;
2921
2922	/* ...the initial AGFL... */
2923	first_bno += xfs_alloc_min_freelist(mp, NULL);
2924
2925	/* ...the free inode btree root... */
2926	if (xfs_has_finobt(mp))
2927		first_bno++;
2928
2929	/* ...the reverse mapping btree root... */
2930	if (xfs_has_rmapbt(mp))
2931		first_bno++;
2932
2933	/* ...the reference count btree... */
2934	if (xfs_has_reflink(mp))
2935		first_bno++;
2936
2937	/*
2938	 * ...and the log, if it is allocated in the first allocation group.
2939	 *
2940	 * This can happen with filesystems that only have a single
2941	 * allocation group, or very odd geometries created by old mkfs
2942	 * versions on very small filesystems.
2943	 */
2944	if (xfs_ag_contains_log(mp, 0))
 
2945		 first_bno += mp->m_sb.sb_logblocks;
2946
2947	/*
2948	 * Now round first_bno up to whatever allocation alignment is given
2949	 * by the filesystem or was passed in.
2950	 */
2951	if (xfs_has_dalign(mp) && igeo->ialloc_align > 0)
2952		first_bno = roundup(first_bno, sunit);
2953	else if (xfs_has_align(mp) &&
2954			mp->m_sb.sb_inoalignmt > 1)
2955		first_bno = roundup(first_bno, mp->m_sb.sb_inoalignmt);
2956
2957	return XFS_AGINO_TO_INO(mp, 0, XFS_AGB_TO_AGINO(mp, first_bno));
2958}
2959
2960/*
2961 * Ensure there are not sparse inode clusters that cross the new EOAG.
2962 *
2963 * This is a no-op for non-spinode filesystems since clusters are always fully
2964 * allocated and checking the bnobt suffices.  However, a spinode filesystem
2965 * could have a record where the upper inodes are free blocks.  If those blocks
2966 * were removed from the filesystem, the inode record would extend beyond EOAG,
2967 * which will be flagged as corruption.
2968 */
2969int
2970xfs_ialloc_check_shrink(
2971	struct xfs_perag	*pag,
2972	struct xfs_trans	*tp,
 
2973	struct xfs_buf		*agibp,
2974	xfs_agblock_t		new_length)
2975{
2976	struct xfs_inobt_rec_incore rec;
2977	struct xfs_btree_cur	*cur;
2978	xfs_agino_t		agino;
 
 
2979	int			has;
2980	int			error;
2981
2982	if (!xfs_has_sparseinodes(pag->pag_mount))
2983		return 0;
2984
2985	cur = xfs_inobt_init_cursor(pag, tp, agibp, XFS_BTNUM_INO);
 
2986
2987	/* Look up the inobt record that would correspond to the new EOFS. */
2988	agino = XFS_AGB_TO_AGINO(pag->pag_mount, new_length);
2989	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &has);
2990	if (error || !has)
2991		goto out;
2992
2993	error = xfs_inobt_get_rec(cur, &rec, &has);
2994	if (error)
2995		goto out;
2996
2997	if (!has) {
2998		error = -EFSCORRUPTED;
2999		goto out;
3000	}
3001
3002	/* If the record covers inodes that would be beyond EOFS, bail out. */
3003	if (rec.ir_startino + XFS_INODES_PER_CHUNK > agino) {
3004		error = -ENOSPC;
3005		goto out;
3006	}
3007out:
3008	xfs_btree_del_cursor(cur, error);
 
3009	return error;
3010}
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
   4 * All Rights Reserved.
   5 */
   6#include "xfs.h"
   7#include "xfs_fs.h"
   8#include "xfs_shared.h"
   9#include "xfs_format.h"
  10#include "xfs_log_format.h"
  11#include "xfs_trans_resv.h"
  12#include "xfs_bit.h"
  13#include "xfs_mount.h"
  14#include "xfs_inode.h"
  15#include "xfs_btree.h"
  16#include "xfs_ialloc.h"
  17#include "xfs_ialloc_btree.h"
  18#include "xfs_alloc.h"
  19#include "xfs_errortag.h"
  20#include "xfs_error.h"
  21#include "xfs_bmap.h"
  22#include "xfs_trans.h"
  23#include "xfs_buf_item.h"
  24#include "xfs_icreate_item.h"
  25#include "xfs_icache.h"
  26#include "xfs_trace.h"
  27#include "xfs_log.h"
  28#include "xfs_rmap.h"
  29#include "xfs_ag.h"
  30
  31/*
  32 * Lookup a record by ino in the btree given by cur.
  33 */
  34int					/* error */
  35xfs_inobt_lookup(
  36	struct xfs_btree_cur	*cur,	/* btree cursor */
  37	xfs_agino_t		ino,	/* starting inode of chunk */
  38	xfs_lookup_t		dir,	/* <=, >=, == */
  39	int			*stat)	/* success/failure */
  40{
  41	cur->bc_rec.i.ir_startino = ino;
  42	cur->bc_rec.i.ir_holemask = 0;
  43	cur->bc_rec.i.ir_count = 0;
  44	cur->bc_rec.i.ir_freecount = 0;
  45	cur->bc_rec.i.ir_free = 0;
  46	return xfs_btree_lookup(cur, dir, stat);
  47}
  48
  49/*
  50 * Update the record referred to by cur to the value given.
  51 * This either works (return 0) or gets an EFSCORRUPTED error.
  52 */
  53STATIC int				/* error */
  54xfs_inobt_update(
  55	struct xfs_btree_cur	*cur,	/* btree cursor */
  56	xfs_inobt_rec_incore_t	*irec)	/* btree record */
  57{
  58	union xfs_btree_rec	rec;
  59
  60	rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
  61	if (xfs_sb_version_hassparseinodes(&cur->bc_mp->m_sb)) {
  62		rec.inobt.ir_u.sp.ir_holemask = cpu_to_be16(irec->ir_holemask);
  63		rec.inobt.ir_u.sp.ir_count = irec->ir_count;
  64		rec.inobt.ir_u.sp.ir_freecount = irec->ir_freecount;
  65	} else {
  66		/* ir_holemask/ir_count not supported on-disk */
  67		rec.inobt.ir_u.f.ir_freecount = cpu_to_be32(irec->ir_freecount);
  68	}
  69	rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
  70	return xfs_btree_update(cur, &rec);
  71}
  72
  73/* Convert on-disk btree record to incore inobt record. */
  74void
  75xfs_inobt_btrec_to_irec(
  76	struct xfs_mount		*mp,
  77	union xfs_btree_rec		*rec,
  78	struct xfs_inobt_rec_incore	*irec)
  79{
  80	irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
  81	if (xfs_sb_version_hassparseinodes(&mp->m_sb)) {
  82		irec->ir_holemask = be16_to_cpu(rec->inobt.ir_u.sp.ir_holemask);
  83		irec->ir_count = rec->inobt.ir_u.sp.ir_count;
  84		irec->ir_freecount = rec->inobt.ir_u.sp.ir_freecount;
  85	} else {
  86		/*
  87		 * ir_holemask/ir_count not supported on-disk. Fill in hardcoded
  88		 * values for full inode chunks.
  89		 */
  90		irec->ir_holemask = XFS_INOBT_HOLEMASK_FULL;
  91		irec->ir_count = XFS_INODES_PER_CHUNK;
  92		irec->ir_freecount =
  93				be32_to_cpu(rec->inobt.ir_u.f.ir_freecount);
  94	}
  95	irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
  96}
  97
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  98/*
  99 * Get the data from the pointed-to record.
 100 */
 101int
 102xfs_inobt_get_rec(
 103	struct xfs_btree_cur		*cur,
 104	struct xfs_inobt_rec_incore	*irec,
 105	int				*stat)
 106{
 107	struct xfs_mount		*mp = cur->bc_mp;
 108	xfs_agnumber_t			agno = cur->bc_ag.pag->pag_agno;
 109	union xfs_btree_rec		*rec;
 
 110	int				error;
 111	uint64_t			realfree;
 112
 113	error = xfs_btree_get_rec(cur, &rec, stat);
 114	if (error || *stat == 0)
 115		return error;
 116
 117	xfs_inobt_btrec_to_irec(mp, rec, irec);
 118
 119	if (!xfs_verify_agino(mp, agno, irec->ir_startino))
 120		goto out_bad_rec;
 121	if (irec->ir_count < XFS_INODES_PER_HOLEMASK_BIT ||
 122	    irec->ir_count > XFS_INODES_PER_CHUNK)
 123		goto out_bad_rec;
 124	if (irec->ir_freecount > XFS_INODES_PER_CHUNK)
 125		goto out_bad_rec;
 126
 127	/* if there are no holes, return the first available offset */
 128	if (!xfs_inobt_issparse(irec->ir_holemask))
 129		realfree = irec->ir_free;
 130	else
 131		realfree = irec->ir_free & xfs_inobt_irec_to_allocmask(irec);
 132	if (hweight64(realfree) != irec->ir_freecount)
 133		goto out_bad_rec;
 134
 135	return 0;
 136
 137out_bad_rec:
 138	xfs_warn(mp,
 139		"%s Inode BTree record corruption in AG %d detected!",
 140		cur->bc_btnum == XFS_BTNUM_INO ? "Used" : "Free", agno);
 141	xfs_warn(mp,
 142"start inode 0x%x, count 0x%x, free 0x%x freemask 0x%llx, holemask 0x%x",
 143		irec->ir_startino, irec->ir_count, irec->ir_freecount,
 144		irec->ir_free, irec->ir_holemask);
 145	return -EFSCORRUPTED;
 146}
 147
 148/*
 149 * Insert a single inobt record. Cursor must already point to desired location.
 150 */
 151int
 152xfs_inobt_insert_rec(
 153	struct xfs_btree_cur	*cur,
 154	uint16_t		holemask,
 155	uint8_t			count,
 156	int32_t			freecount,
 157	xfs_inofree_t		free,
 158	int			*stat)
 159{
 160	cur->bc_rec.i.ir_holemask = holemask;
 161	cur->bc_rec.i.ir_count = count;
 162	cur->bc_rec.i.ir_freecount = freecount;
 163	cur->bc_rec.i.ir_free = free;
 164	return xfs_btree_insert(cur, stat);
 165}
 166
 167/*
 168 * Insert records describing a newly allocated inode chunk into the inobt.
 169 */
 170STATIC int
 171xfs_inobt_insert(
 172	struct xfs_mount	*mp,
 173	struct xfs_trans	*tp,
 174	struct xfs_buf		*agbp,
 175	struct xfs_perag	*pag,
 176	xfs_agino_t		newino,
 177	xfs_agino_t		newlen,
 178	xfs_btnum_t		btnum)
 179{
 180	struct xfs_btree_cur	*cur;
 181	xfs_agino_t		thisino;
 182	int			i;
 183	int			error;
 184
 185	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, btnum);
 186
 187	for (thisino = newino;
 188	     thisino < newino + newlen;
 189	     thisino += XFS_INODES_PER_CHUNK) {
 190		error = xfs_inobt_lookup(cur, thisino, XFS_LOOKUP_EQ, &i);
 191		if (error) {
 192			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 193			return error;
 194		}
 195		ASSERT(i == 0);
 196
 197		error = xfs_inobt_insert_rec(cur, XFS_INOBT_HOLEMASK_FULL,
 198					     XFS_INODES_PER_CHUNK,
 199					     XFS_INODES_PER_CHUNK,
 200					     XFS_INOBT_ALL_FREE, &i);
 201		if (error) {
 202			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 203			return error;
 204		}
 205		ASSERT(i == 1);
 206	}
 207
 208	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 209
 210	return 0;
 211}
 212
 213/*
 214 * Verify that the number of free inodes in the AGI is correct.
 215 */
 216#ifdef DEBUG
 217static int
 218xfs_check_agi_freecount(
 219	struct xfs_btree_cur	*cur)
 220{
 221	if (cur->bc_nlevels == 1) {
 222		xfs_inobt_rec_incore_t rec;
 223		int		freecount = 0;
 224		int		error;
 225		int		i;
 226
 227		error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
 228		if (error)
 229			return error;
 230
 231		do {
 232			error = xfs_inobt_get_rec(cur, &rec, &i);
 233			if (error)
 234				return error;
 235
 236			if (i) {
 237				freecount += rec.ir_freecount;
 238				error = xfs_btree_increment(cur, 0, &i);
 239				if (error)
 240					return error;
 241			}
 242		} while (i == 1);
 243
 244		if (!XFS_FORCED_SHUTDOWN(cur->bc_mp))
 245			ASSERT(freecount == cur->bc_ag.pag->pagi_freecount);
 246	}
 247	return 0;
 248}
 249#else
 250#define xfs_check_agi_freecount(cur)	0
 251#endif
 252
 253/*
 254 * Initialise a new set of inodes. When called without a transaction context
 255 * (e.g. from recovery) we initiate a delayed write of the inode buffers rather
 256 * than logging them (which in a transaction context puts them into the AIL
 257 * for writeback rather than the xfsbufd queue).
 258 */
 259int
 260xfs_ialloc_inode_init(
 261	struct xfs_mount	*mp,
 262	struct xfs_trans	*tp,
 263	struct list_head	*buffer_list,
 264	int			icount,
 265	xfs_agnumber_t		agno,
 266	xfs_agblock_t		agbno,
 267	xfs_agblock_t		length,
 268	unsigned int		gen)
 269{
 270	struct xfs_buf		*fbuf;
 271	struct xfs_dinode	*free;
 272	int			nbufs;
 273	int			version;
 274	int			i, j;
 275	xfs_daddr_t		d;
 276	xfs_ino_t		ino = 0;
 277	int			error;
 278
 279	/*
 280	 * Loop over the new block(s), filling in the inodes.  For small block
 281	 * sizes, manipulate the inodes in buffers  which are multiples of the
 282	 * blocks size.
 283	 */
 284	nbufs = length / M_IGEO(mp)->blocks_per_cluster;
 285
 286	/*
 287	 * Figure out what version number to use in the inodes we create.  If
 288	 * the superblock version has caught up to the one that supports the new
 289	 * inode format, then use the new inode version.  Otherwise use the old
 290	 * version so that old kernels will continue to be able to use the file
 291	 * system.
 292	 *
 293	 * For v3 inodes, we also need to write the inode number into the inode,
 294	 * so calculate the first inode number of the chunk here as
 295	 * XFS_AGB_TO_AGINO() only works within a filesystem block, not
 296	 * across multiple filesystem blocks (such as a cluster) and so cannot
 297	 * be used in the cluster buffer loop below.
 298	 *
 299	 * Further, because we are writing the inode directly into the buffer
 300	 * and calculating a CRC on the entire inode, we have ot log the entire
 301	 * inode so that the entire range the CRC covers is present in the log.
 302	 * That means for v3 inode we log the entire buffer rather than just the
 303	 * inode cores.
 304	 */
 305	if (xfs_sb_version_has_v3inode(&mp->m_sb)) {
 306		version = 3;
 307		ino = XFS_AGINO_TO_INO(mp, agno, XFS_AGB_TO_AGINO(mp, agbno));
 308
 309		/*
 310		 * log the initialisation that is about to take place as an
 311		 * logical operation. This means the transaction does not
 312		 * need to log the physical changes to the inode buffers as log
 313		 * recovery will know what initialisation is actually needed.
 314		 * Hence we only need to log the buffers as "ordered" buffers so
 315		 * they track in the AIL as if they were physically logged.
 316		 */
 317		if (tp)
 318			xfs_icreate_log(tp, agno, agbno, icount,
 319					mp->m_sb.sb_inodesize, length, gen);
 320	} else
 321		version = 2;
 322
 323	for (j = 0; j < nbufs; j++) {
 324		/*
 325		 * Get the block.
 326		 */
 327		d = XFS_AGB_TO_DADDR(mp, agno, agbno +
 328				(j * M_IGEO(mp)->blocks_per_cluster));
 329		error = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 330				mp->m_bsize * M_IGEO(mp)->blocks_per_cluster,
 331				XBF_UNMAPPED, &fbuf);
 332		if (error)
 333			return error;
 334
 335		/* Initialize the inode buffers and log them appropriately. */
 336		fbuf->b_ops = &xfs_inode_buf_ops;
 337		xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
 338		for (i = 0; i < M_IGEO(mp)->inodes_per_cluster; i++) {
 339			int	ioffset = i << mp->m_sb.sb_inodelog;
 340			uint	isize = XFS_DINODE_SIZE(&mp->m_sb);
 341
 342			free = xfs_make_iptr(mp, fbuf, i);
 343			free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
 344			free->di_version = version;
 345			free->di_gen = cpu_to_be32(gen);
 346			free->di_next_unlinked = cpu_to_be32(NULLAGINO);
 347
 348			if (version == 3) {
 349				free->di_ino = cpu_to_be64(ino);
 350				ino++;
 351				uuid_copy(&free->di_uuid,
 352					  &mp->m_sb.sb_meta_uuid);
 353				xfs_dinode_calc_crc(mp, free);
 354			} else if (tp) {
 355				/* just log the inode core */
 356				xfs_trans_log_buf(tp, fbuf, ioffset,
 357						  ioffset + isize - 1);
 358			}
 359		}
 360
 361		if (tp) {
 362			/*
 363			 * Mark the buffer as an inode allocation buffer so it
 364			 * sticks in AIL at the point of this allocation
 365			 * transaction. This ensures the they are on disk before
 366			 * the tail of the log can be moved past this
 367			 * transaction (i.e. by preventing relogging from moving
 368			 * it forward in the log).
 369			 */
 370			xfs_trans_inode_alloc_buf(tp, fbuf);
 371			if (version == 3) {
 372				/*
 373				 * Mark the buffer as ordered so that they are
 374				 * not physically logged in the transaction but
 375				 * still tracked in the AIL as part of the
 376				 * transaction and pin the log appropriately.
 377				 */
 378				xfs_trans_ordered_buf(tp, fbuf);
 379			}
 380		} else {
 381			fbuf->b_flags |= XBF_DONE;
 382			xfs_buf_delwri_queue(fbuf, buffer_list);
 383			xfs_buf_relse(fbuf);
 384		}
 385	}
 386	return 0;
 387}
 388
 389/*
 390 * Align startino and allocmask for a recently allocated sparse chunk such that
 391 * they are fit for insertion (or merge) into the on-disk inode btrees.
 392 *
 393 * Background:
 394 *
 395 * When enabled, sparse inode support increases the inode alignment from cluster
 396 * size to inode chunk size. This means that the minimum range between two
 397 * non-adjacent inode records in the inobt is large enough for a full inode
 398 * record. This allows for cluster sized, cluster aligned block allocation
 399 * without need to worry about whether the resulting inode record overlaps with
 400 * another record in the tree. Without this basic rule, we would have to deal
 401 * with the consequences of overlap by potentially undoing recent allocations in
 402 * the inode allocation codepath.
 403 *
 404 * Because of this alignment rule (which is enforced on mount), there are two
 405 * inobt possibilities for newly allocated sparse chunks. One is that the
 406 * aligned inode record for the chunk covers a range of inodes not already
 407 * covered in the inobt (i.e., it is safe to insert a new sparse record). The
 408 * other is that a record already exists at the aligned startino that considers
 409 * the newly allocated range as sparse. In the latter case, record content is
 410 * merged in hope that sparse inode chunks fill to full chunks over time.
 411 */
 412STATIC void
 413xfs_align_sparse_ino(
 414	struct xfs_mount		*mp,
 415	xfs_agino_t			*startino,
 416	uint16_t			*allocmask)
 417{
 418	xfs_agblock_t			agbno;
 419	xfs_agblock_t			mod;
 420	int				offset;
 421
 422	agbno = XFS_AGINO_TO_AGBNO(mp, *startino);
 423	mod = agbno % mp->m_sb.sb_inoalignmt;
 424	if (!mod)
 425		return;
 426
 427	/* calculate the inode offset and align startino */
 428	offset = XFS_AGB_TO_AGINO(mp, mod);
 429	*startino -= offset;
 430
 431	/*
 432	 * Since startino has been aligned down, left shift allocmask such that
 433	 * it continues to represent the same physical inodes relative to the
 434	 * new startino.
 435	 */
 436	*allocmask <<= offset / XFS_INODES_PER_HOLEMASK_BIT;
 437}
 438
 439/*
 440 * Determine whether the source inode record can merge into the target. Both
 441 * records must be sparse, the inode ranges must match and there must be no
 442 * allocation overlap between the records.
 443 */
 444STATIC bool
 445__xfs_inobt_can_merge(
 446	struct xfs_inobt_rec_incore	*trec,	/* tgt record */
 447	struct xfs_inobt_rec_incore	*srec)	/* src record */
 448{
 449	uint64_t			talloc;
 450	uint64_t			salloc;
 451
 452	/* records must cover the same inode range */
 453	if (trec->ir_startino != srec->ir_startino)
 454		return false;
 455
 456	/* both records must be sparse */
 457	if (!xfs_inobt_issparse(trec->ir_holemask) ||
 458	    !xfs_inobt_issparse(srec->ir_holemask))
 459		return false;
 460
 461	/* both records must track some inodes */
 462	if (!trec->ir_count || !srec->ir_count)
 463		return false;
 464
 465	/* can't exceed capacity of a full record */
 466	if (trec->ir_count + srec->ir_count > XFS_INODES_PER_CHUNK)
 467		return false;
 468
 469	/* verify there is no allocation overlap */
 470	talloc = xfs_inobt_irec_to_allocmask(trec);
 471	salloc = xfs_inobt_irec_to_allocmask(srec);
 472	if (talloc & salloc)
 473		return false;
 474
 475	return true;
 476}
 477
 478/*
 479 * Merge the source inode record into the target. The caller must call
 480 * __xfs_inobt_can_merge() to ensure the merge is valid.
 481 */
 482STATIC void
 483__xfs_inobt_rec_merge(
 484	struct xfs_inobt_rec_incore	*trec,	/* target */
 485	struct xfs_inobt_rec_incore	*srec)	/* src */
 486{
 487	ASSERT(trec->ir_startino == srec->ir_startino);
 488
 489	/* combine the counts */
 490	trec->ir_count += srec->ir_count;
 491	trec->ir_freecount += srec->ir_freecount;
 492
 493	/*
 494	 * Merge the holemask and free mask. For both fields, 0 bits refer to
 495	 * allocated inodes. We combine the allocated ranges with bitwise AND.
 496	 */
 497	trec->ir_holemask &= srec->ir_holemask;
 498	trec->ir_free &= srec->ir_free;
 499}
 500
 501/*
 502 * Insert a new sparse inode chunk into the associated inode btree. The inode
 503 * record for the sparse chunk is pre-aligned to a startino that should match
 504 * any pre-existing sparse inode record in the tree. This allows sparse chunks
 505 * to fill over time.
 506 *
 507 * This function supports two modes of handling preexisting records depending on
 508 * the merge flag. If merge is true, the provided record is merged with the
 509 * existing record and updated in place. The merged record is returned in nrec.
 510 * If merge is false, an existing record is replaced with the provided record.
 511 * If no preexisting record exists, the provided record is always inserted.
 512 *
 513 * It is considered corruption if a merge is requested and not possible. Given
 514 * the sparse inode alignment constraints, this should never happen.
 515 */
 516STATIC int
 517xfs_inobt_insert_sprec(
 518	struct xfs_mount		*mp,
 519	struct xfs_trans		*tp,
 520	struct xfs_buf			*agbp,
 521	struct xfs_perag		*pag,
 522	int				btnum,
 523	struct xfs_inobt_rec_incore	*nrec,	/* in/out: new/merged rec. */
 524	bool				merge)	/* merge or replace */
 525{
 
 526	struct xfs_btree_cur		*cur;
 527	int				error;
 528	int				i;
 529	struct xfs_inobt_rec_incore	rec;
 530
 531	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, btnum);
 532
 533	/* the new record is pre-aligned so we know where to look */
 534	error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
 535	if (error)
 536		goto error;
 537	/* if nothing there, insert a new record and return */
 538	if (i == 0) {
 539		error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
 540					     nrec->ir_count, nrec->ir_freecount,
 541					     nrec->ir_free, &i);
 542		if (error)
 543			goto error;
 544		if (XFS_IS_CORRUPT(mp, i != 1)) {
 545			error = -EFSCORRUPTED;
 546			goto error;
 547		}
 548
 549		goto out;
 550	}
 551
 552	/*
 553	 * A record exists at this startino. Merge or replace the record
 554	 * depending on what we've been asked to do.
 555	 */
 556	if (merge) {
 557		error = xfs_inobt_get_rec(cur, &rec, &i);
 558		if (error)
 559			goto error;
 560		if (XFS_IS_CORRUPT(mp, i != 1)) {
 561			error = -EFSCORRUPTED;
 562			goto error;
 563		}
 564		if (XFS_IS_CORRUPT(mp, rec.ir_startino != nrec->ir_startino)) {
 565			error = -EFSCORRUPTED;
 566			goto error;
 567		}
 568
 569		/*
 570		 * This should never fail. If we have coexisting records that
 571		 * cannot merge, something is seriously wrong.
 572		 */
 573		if (XFS_IS_CORRUPT(mp, !__xfs_inobt_can_merge(nrec, &rec))) {
 574			error = -EFSCORRUPTED;
 575			goto error;
 576		}
 577
 578		trace_xfs_irec_merge_pre(mp, pag->pag_agno, rec.ir_startino,
 579					 rec.ir_holemask, nrec->ir_startino,
 580					 nrec->ir_holemask);
 581
 582		/* merge to nrec to output the updated record */
 583		__xfs_inobt_rec_merge(nrec, &rec);
 584
 585		trace_xfs_irec_merge_post(mp, pag->pag_agno, nrec->ir_startino,
 586					  nrec->ir_holemask);
 587
 588		error = xfs_inobt_rec_check_count(mp, nrec);
 589		if (error)
 590			goto error;
 591	}
 592
 593	error = xfs_inobt_update(cur, nrec);
 594	if (error)
 595		goto error;
 596
 597out:
 598	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 599	return 0;
 600error:
 601	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 602	return error;
 603}
 604
 605/*
 606 * Allocate new inodes in the allocation group specified by agbp.  Returns 0 if
 607 * inodes were allocated in this AG; -EAGAIN if there was no space in this AG so
 608 * the caller knows it can try another AG, a hard -ENOSPC when over the maximum
 609 * inode count threshold, or the usual negative error code for other errors.
 610 */
 611STATIC int
 612xfs_ialloc_ag_alloc(
 
 613	struct xfs_trans	*tp,
 614	struct xfs_buf		*agbp,
 615	struct xfs_perag	*pag)
 616{
 617	struct xfs_agi		*agi;
 618	struct xfs_alloc_arg	args;
 619	int			error;
 620	xfs_agino_t		newino;		/* new first inode's number */
 621	xfs_agino_t		newlen;		/* new number of inodes */
 622	int			isaligned = 0;	/* inode allocation at stripe */
 623						/* unit boundary */
 624	/* init. to full chunk */
 625	struct xfs_inobt_rec_incore rec;
 626	struct xfs_ino_geometry	*igeo = M_IGEO(tp->t_mountp);
 627	uint16_t		allocmask = (uint16_t) -1;
 628	int			do_sparse = 0;
 629
 630	memset(&args, 0, sizeof(args));
 631	args.tp = tp;
 632	args.mp = tp->t_mountp;
 633	args.fsbno = NULLFSBLOCK;
 634	args.oinfo = XFS_RMAP_OINFO_INODES;
 
 635
 636#ifdef DEBUG
 637	/* randomly do sparse inode allocations */
 638	if (xfs_sb_version_hassparseinodes(&tp->t_mountp->m_sb) &&
 639	    igeo->ialloc_min_blks < igeo->ialloc_blks)
 640		do_sparse = prandom_u32() & 1;
 641#endif
 642
 643	/*
 644	 * Locking will ensure that we don't have two callers in here
 645	 * at one time.
 646	 */
 647	newlen = igeo->ialloc_inos;
 648	if (igeo->maxicount &&
 649	    percpu_counter_read_positive(&args.mp->m_icount) + newlen >
 650							igeo->maxicount)
 651		return -ENOSPC;
 652	args.minlen = args.maxlen = igeo->ialloc_blks;
 653	/*
 654	 * First try to allocate inodes contiguous with the last-allocated
 655	 * chunk of inodes.  If the filesystem is striped, this will fill
 656	 * an entire stripe unit with inodes.
 657	 */
 658	agi = agbp->b_addr;
 659	newino = be32_to_cpu(agi->agi_newino);
 660	args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
 661		     igeo->ialloc_blks;
 662	if (do_sparse)
 663		goto sparse_alloc;
 664	if (likely(newino != NULLAGINO &&
 665		  (args.agbno < be32_to_cpu(agi->agi_length)))) {
 666		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 667		args.type = XFS_ALLOCTYPE_THIS_BNO;
 668		args.prod = 1;
 669
 670		/*
 671		 * We need to take into account alignment here to ensure that
 672		 * we don't modify the free list if we fail to have an exact
 673		 * block. If we don't have an exact match, and every oher
 674		 * attempt allocation attempt fails, we'll end up cancelling
 675		 * a dirty transaction and shutting down.
 676		 *
 677		 * For an exact allocation, alignment must be 1,
 678		 * however we need to take cluster alignment into account when
 679		 * fixing up the freelist. Use the minalignslop field to
 680		 * indicate that extra blocks might be required for alignment,
 681		 * but not to use them in the actual exact allocation.
 682		 */
 683		args.alignment = 1;
 684		args.minalignslop = igeo->cluster_align - 1;
 685
 686		/* Allow space for the inode btree to split. */
 687		args.minleft = igeo->inobt_maxlevels;
 688		if ((error = xfs_alloc_vextent(&args)))
 
 
 
 689			return error;
 690
 691		/*
 692		 * This request might have dirtied the transaction if the AG can
 693		 * satisfy the request, but the exact block was not available.
 694		 * If the allocation did fail, subsequent requests will relax
 695		 * the exact agbno requirement and increase the alignment
 696		 * instead. It is critical that the total size of the request
 697		 * (len + alignment + slop) does not increase from this point
 698		 * on, so reset minalignslop to ensure it is not included in
 699		 * subsequent requests.
 700		 */
 701		args.minalignslop = 0;
 702	}
 703
 704	if (unlikely(args.fsbno == NULLFSBLOCK)) {
 705		/*
 706		 * Set the alignment for the allocation.
 707		 * If stripe alignment is turned on then align at stripe unit
 708		 * boundary.
 709		 * If the cluster size is smaller than a filesystem block
 710		 * then we're doing I/O for inodes in filesystem block size
 711		 * pieces, so don't need alignment anyway.
 712		 */
 713		isaligned = 0;
 714		if (igeo->ialloc_align) {
 715			ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
 716			args.alignment = args.mp->m_dalign;
 717			isaligned = 1;
 718		} else
 719			args.alignment = igeo->cluster_align;
 720		/*
 721		 * Need to figure out where to allocate the inode blocks.
 722		 * Ideally they should be spaced out through the a.g.
 723		 * For now, just allocate blocks up front.
 724		 */
 725		args.agbno = be32_to_cpu(agi->agi_root);
 726		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 727		/*
 728		 * Allocate a fixed-size extent of inodes.
 729		 */
 730		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 731		args.prod = 1;
 732		/*
 733		 * Allow space for the inode btree to split.
 734		 */
 735		args.minleft = igeo->inobt_maxlevels;
 736		if ((error = xfs_alloc_vextent(&args)))
 
 
 
 737			return error;
 738	}
 739
 740	/*
 741	 * If stripe alignment is turned on, then try again with cluster
 742	 * alignment.
 743	 */
 744	if (isaligned && args.fsbno == NULLFSBLOCK) {
 745		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 746		args.agbno = be32_to_cpu(agi->agi_root);
 747		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 748		args.alignment = igeo->cluster_align;
 749		if ((error = xfs_alloc_vextent(&args)))
 
 
 
 750			return error;
 751	}
 752
 753	/*
 754	 * Finally, try a sparse allocation if the filesystem supports it and
 755	 * the sparse allocation length is smaller than a full chunk.
 756	 */
 757	if (xfs_sb_version_hassparseinodes(&args.mp->m_sb) &&
 758	    igeo->ialloc_min_blks < igeo->ialloc_blks &&
 759	    args.fsbno == NULLFSBLOCK) {
 760sparse_alloc:
 761		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 762		args.agbno = be32_to_cpu(agi->agi_root);
 763		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 764		args.alignment = args.mp->m_sb.sb_spino_align;
 765		args.prod = 1;
 766
 767		args.minlen = igeo->ialloc_min_blks;
 768		args.maxlen = args.minlen;
 769
 770		/*
 771		 * The inode record will be aligned to full chunk size. We must
 772		 * prevent sparse allocation from AG boundaries that result in
 773		 * invalid inode records, such as records that start at agbno 0
 774		 * or extend beyond the AG.
 775		 *
 776		 * Set min agbno to the first aligned, non-zero agbno and max to
 777		 * the last aligned agbno that is at least one full chunk from
 778		 * the end of the AG.
 779		 */
 780		args.min_agbno = args.mp->m_sb.sb_inoalignmt;
 781		args.max_agbno = round_down(args.mp->m_sb.sb_agblocks,
 782					    args.mp->m_sb.sb_inoalignmt) -
 783				 igeo->ialloc_blks;
 784
 785		error = xfs_alloc_vextent(&args);
 
 
 786		if (error)
 787			return error;
 788
 789		newlen = XFS_AGB_TO_AGINO(args.mp, args.len);
 790		ASSERT(newlen <= XFS_INODES_PER_CHUNK);
 791		allocmask = (1 << (newlen / XFS_INODES_PER_HOLEMASK_BIT)) - 1;
 792	}
 793
 794	if (args.fsbno == NULLFSBLOCK)
 795		return -EAGAIN;
 796
 797	ASSERT(args.len == args.minlen);
 798
 799	/*
 800	 * Stamp and write the inode buffers.
 801	 *
 802	 * Seed the new inode cluster with a random generation number. This
 803	 * prevents short-term reuse of generation numbers if a chunk is
 804	 * freed and then immediately reallocated. We use random numbers
 805	 * rather than a linear progression to prevent the next generation
 806	 * number from being easily guessable.
 807	 */
 808	error = xfs_ialloc_inode_init(args.mp, tp, NULL, newlen, pag->pag_agno,
 809			args.agbno, args.len, prandom_u32());
 810
 811	if (error)
 812		return error;
 813	/*
 814	 * Convert the results.
 815	 */
 816	newino = XFS_AGB_TO_AGINO(args.mp, args.agbno);
 817
 818	if (xfs_inobt_issparse(~allocmask)) {
 819		/*
 820		 * We've allocated a sparse chunk. Align the startino and mask.
 821		 */
 822		xfs_align_sparse_ino(args.mp, &newino, &allocmask);
 823
 824		rec.ir_startino = newino;
 825		rec.ir_holemask = ~allocmask;
 826		rec.ir_count = newlen;
 827		rec.ir_freecount = newlen;
 828		rec.ir_free = XFS_INOBT_ALL_FREE;
 829
 830		/*
 831		 * Insert the sparse record into the inobt and allow for a merge
 832		 * if necessary. If a merge does occur, rec is updated to the
 833		 * merged record.
 834		 */
 835		error = xfs_inobt_insert_sprec(args.mp, tp, agbp, pag,
 836				XFS_BTNUM_INO, &rec, true);
 837		if (error == -EFSCORRUPTED) {
 838			xfs_alert(args.mp,
 839	"invalid sparse inode record: ino 0x%llx holemask 0x%x count %u",
 840				  XFS_AGINO_TO_INO(args.mp, pag->pag_agno,
 841						   rec.ir_startino),
 842				  rec.ir_holemask, rec.ir_count);
 843			xfs_force_shutdown(args.mp, SHUTDOWN_CORRUPT_INCORE);
 844		}
 845		if (error)
 846			return error;
 847
 848		/*
 849		 * We can't merge the part we've just allocated as for the inobt
 850		 * due to finobt semantics. The original record may or may not
 851		 * exist independent of whether physical inodes exist in this
 852		 * sparse chunk.
 853		 *
 854		 * We must update the finobt record based on the inobt record.
 855		 * rec contains the fully merged and up to date inobt record
 856		 * from the previous call. Set merge false to replace any
 857		 * existing record with this one.
 858		 */
 859		if (xfs_sb_version_hasfinobt(&args.mp->m_sb)) {
 860			error = xfs_inobt_insert_sprec(args.mp, tp, agbp, pag,
 861				       XFS_BTNUM_FINO, &rec, false);
 862			if (error)
 863				return error;
 864		}
 865	} else {
 866		/* full chunk - insert new records to both btrees */
 867		error = xfs_inobt_insert(args.mp, tp, agbp, pag, newino, newlen,
 868					 XFS_BTNUM_INO);
 869		if (error)
 870			return error;
 871
 872		if (xfs_sb_version_hasfinobt(&args.mp->m_sb)) {
 873			error = xfs_inobt_insert(args.mp, tp, agbp, pag, newino,
 874						 newlen, XFS_BTNUM_FINO);
 875			if (error)
 876				return error;
 877		}
 878	}
 879
 880	/*
 881	 * Update AGI counts and newino.
 882	 */
 883	be32_add_cpu(&agi->agi_count, newlen);
 884	be32_add_cpu(&agi->agi_freecount, newlen);
 885	pag->pagi_freecount += newlen;
 886	pag->pagi_count += newlen;
 887	agi->agi_newino = cpu_to_be32(newino);
 888
 889	/*
 890	 * Log allocation group header fields
 891	 */
 892	xfs_ialloc_log_agi(tp, agbp,
 893		XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
 894	/*
 895	 * Modify/log superblock values for inode count and inode free count.
 896	 */
 897	xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
 898	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
 899	return 0;
 900}
 901
 902/*
 903 * Try to retrieve the next record to the left/right from the current one.
 904 */
 905STATIC int
 906xfs_ialloc_next_rec(
 907	struct xfs_btree_cur	*cur,
 908	xfs_inobt_rec_incore_t	*rec,
 909	int			*done,
 910	int			left)
 911{
 912	int                     error;
 913	int			i;
 914
 915	if (left)
 916		error = xfs_btree_decrement(cur, 0, &i);
 917	else
 918		error = xfs_btree_increment(cur, 0, &i);
 919
 920	if (error)
 921		return error;
 922	*done = !i;
 923	if (i) {
 924		error = xfs_inobt_get_rec(cur, rec, &i);
 925		if (error)
 926			return error;
 927		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 928			return -EFSCORRUPTED;
 929	}
 930
 931	return 0;
 932}
 933
 934STATIC int
 935xfs_ialloc_get_rec(
 936	struct xfs_btree_cur	*cur,
 937	xfs_agino_t		agino,
 938	xfs_inobt_rec_incore_t	*rec,
 939	int			*done)
 940{
 941	int                     error;
 942	int			i;
 943
 944	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
 945	if (error)
 946		return error;
 947	*done = !i;
 948	if (i) {
 949		error = xfs_inobt_get_rec(cur, rec, &i);
 950		if (error)
 951			return error;
 952		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 953			return -EFSCORRUPTED;
 954	}
 955
 956	return 0;
 957}
 958
 959/*
 960 * Return the offset of the first free inode in the record. If the inode chunk
 961 * is sparsely allocated, we convert the record holemask to inode granularity
 962 * and mask off the unallocated regions from the inode free mask.
 963 */
 964STATIC int
 965xfs_inobt_first_free_inode(
 966	struct xfs_inobt_rec_incore	*rec)
 967{
 968	xfs_inofree_t			realfree;
 969
 970	/* if there are no holes, return the first available offset */
 971	if (!xfs_inobt_issparse(rec->ir_holemask))
 972		return xfs_lowbit64(rec->ir_free);
 973
 974	realfree = xfs_inobt_irec_to_allocmask(rec);
 975	realfree &= rec->ir_free;
 976
 977	return xfs_lowbit64(realfree);
 978}
 979
 980/*
 981 * Allocate an inode using the inobt-only algorithm.
 982 */
 983STATIC int
 984xfs_dialloc_ag_inobt(
 
 985	struct xfs_trans	*tp,
 986	struct xfs_buf		*agbp,
 987	struct xfs_perag	*pag,
 988	xfs_ino_t		parent,
 989	xfs_ino_t		*inop)
 990{
 991	struct xfs_mount	*mp = tp->t_mountp;
 992	struct xfs_agi		*agi = agbp->b_addr;
 993	xfs_agnumber_t		pagno = XFS_INO_TO_AGNO(mp, parent);
 994	xfs_agino_t		pagino = XFS_INO_TO_AGINO(mp, parent);
 995	struct xfs_btree_cur	*cur, *tcur;
 996	struct xfs_inobt_rec_incore rec, trec;
 997	xfs_ino_t		ino;
 998	int			error;
 999	int			offset;
1000	int			i, j;
1001	int			searchdistance = 10;
1002
1003	ASSERT(pag->pagi_init);
1004	ASSERT(pag->pagi_inodeok);
1005	ASSERT(pag->pagi_freecount > 0);
1006
1007 restart_pagno:
1008	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1009	/*
1010	 * If pagino is 0 (this is the root inode allocation) use newino.
1011	 * This must work because we've just allocated some.
1012	 */
1013	if (!pagino)
1014		pagino = be32_to_cpu(agi->agi_newino);
1015
1016	error = xfs_check_agi_freecount(cur);
1017	if (error)
1018		goto error0;
1019
1020	/*
1021	 * If in the same AG as the parent, try to get near the parent.
1022	 */
1023	if (pagno == pag->pag_agno) {
1024		int		doneleft;	/* done, to the left */
1025		int		doneright;	/* done, to the right */
1026
1027		error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
1028		if (error)
1029			goto error0;
1030		if (XFS_IS_CORRUPT(mp, i != 1)) {
1031			error = -EFSCORRUPTED;
1032			goto error0;
1033		}
1034
1035		error = xfs_inobt_get_rec(cur, &rec, &j);
1036		if (error)
1037			goto error0;
1038		if (XFS_IS_CORRUPT(mp, j != 1)) {
1039			error = -EFSCORRUPTED;
1040			goto error0;
1041		}
1042
1043		if (rec.ir_freecount > 0) {
1044			/*
1045			 * Found a free inode in the same chunk
1046			 * as the parent, done.
1047			 */
1048			goto alloc_inode;
1049		}
1050
1051
1052		/*
1053		 * In the same AG as parent, but parent's chunk is full.
1054		 */
1055
1056		/* duplicate the cursor, search left & right simultaneously */
1057		error = xfs_btree_dup_cursor(cur, &tcur);
1058		if (error)
1059			goto error0;
1060
1061		/*
1062		 * Skip to last blocks looked up if same parent inode.
1063		 */
1064		if (pagino != NULLAGINO &&
1065		    pag->pagl_pagino == pagino &&
1066		    pag->pagl_leftrec != NULLAGINO &&
1067		    pag->pagl_rightrec != NULLAGINO) {
1068			error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
1069						   &trec, &doneleft);
1070			if (error)
1071				goto error1;
1072
1073			error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
1074						   &rec, &doneright);
1075			if (error)
1076				goto error1;
1077		} else {
1078			/* search left with tcur, back up 1 record */
1079			error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
1080			if (error)
1081				goto error1;
1082
1083			/* search right with cur, go forward 1 record. */
1084			error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
1085			if (error)
1086				goto error1;
1087		}
1088
1089		/*
1090		 * Loop until we find an inode chunk with a free inode.
1091		 */
1092		while (--searchdistance > 0 && (!doneleft || !doneright)) {
1093			int	useleft;  /* using left inode chunk this time */
1094
1095			/* figure out the closer block if both are valid. */
1096			if (!doneleft && !doneright) {
1097				useleft = pagino -
1098				 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
1099				  rec.ir_startino - pagino;
1100			} else {
1101				useleft = !doneleft;
1102			}
1103
1104			/* free inodes to the left? */
1105			if (useleft && trec.ir_freecount) {
1106				xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1107				cur = tcur;
1108
1109				pag->pagl_leftrec = trec.ir_startino;
1110				pag->pagl_rightrec = rec.ir_startino;
1111				pag->pagl_pagino = pagino;
1112				rec = trec;
1113				goto alloc_inode;
1114			}
1115
1116			/* free inodes to the right? */
1117			if (!useleft && rec.ir_freecount) {
1118				xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1119
1120				pag->pagl_leftrec = trec.ir_startino;
1121				pag->pagl_rightrec = rec.ir_startino;
1122				pag->pagl_pagino = pagino;
1123				goto alloc_inode;
1124			}
1125
1126			/* get next record to check */
1127			if (useleft) {
1128				error = xfs_ialloc_next_rec(tcur, &trec,
1129								 &doneleft, 1);
1130			} else {
1131				error = xfs_ialloc_next_rec(cur, &rec,
1132								 &doneright, 0);
1133			}
1134			if (error)
1135				goto error1;
1136		}
1137
1138		if (searchdistance <= 0) {
1139			/*
1140			 * Not in range - save last search
1141			 * location and allocate a new inode
1142			 */
1143			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1144			pag->pagl_leftrec = trec.ir_startino;
1145			pag->pagl_rightrec = rec.ir_startino;
1146			pag->pagl_pagino = pagino;
1147
1148		} else {
1149			/*
1150			 * We've reached the end of the btree. because
1151			 * we are only searching a small chunk of the
1152			 * btree each search, there is obviously free
1153			 * inodes closer to the parent inode than we
1154			 * are now. restart the search again.
1155			 */
1156			pag->pagl_pagino = NULLAGINO;
1157			pag->pagl_leftrec = NULLAGINO;
1158			pag->pagl_rightrec = NULLAGINO;
1159			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1160			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1161			goto restart_pagno;
1162		}
1163	}
1164
1165	/*
1166	 * In a different AG from the parent.
1167	 * See if the most recently allocated block has any free.
1168	 */
1169	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1170		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1171					 XFS_LOOKUP_EQ, &i);
1172		if (error)
1173			goto error0;
1174
1175		if (i == 1) {
1176			error = xfs_inobt_get_rec(cur, &rec, &j);
1177			if (error)
1178				goto error0;
1179
1180			if (j == 1 && rec.ir_freecount > 0) {
1181				/*
1182				 * The last chunk allocated in the group
1183				 * still has a free inode.
1184				 */
1185				goto alloc_inode;
1186			}
1187		}
1188	}
1189
1190	/*
1191	 * None left in the last group, search the whole AG
1192	 */
1193	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1194	if (error)
1195		goto error0;
1196	if (XFS_IS_CORRUPT(mp, i != 1)) {
1197		error = -EFSCORRUPTED;
1198		goto error0;
1199	}
1200
1201	for (;;) {
1202		error = xfs_inobt_get_rec(cur, &rec, &i);
1203		if (error)
1204			goto error0;
1205		if (XFS_IS_CORRUPT(mp, i != 1)) {
1206			error = -EFSCORRUPTED;
1207			goto error0;
1208		}
1209		if (rec.ir_freecount > 0)
1210			break;
1211		error = xfs_btree_increment(cur, 0, &i);
1212		if (error)
1213			goto error0;
1214		if (XFS_IS_CORRUPT(mp, i != 1)) {
1215			error = -EFSCORRUPTED;
1216			goto error0;
1217		}
1218	}
1219
1220alloc_inode:
1221	offset = xfs_inobt_first_free_inode(&rec);
1222	ASSERT(offset >= 0);
1223	ASSERT(offset < XFS_INODES_PER_CHUNK);
1224	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1225				   XFS_INODES_PER_CHUNK) == 0);
1226	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1227	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1228	rec.ir_freecount--;
1229	error = xfs_inobt_update(cur, &rec);
1230	if (error)
1231		goto error0;
1232	be32_add_cpu(&agi->agi_freecount, -1);
1233	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1234	pag->pagi_freecount--;
1235
1236	error = xfs_check_agi_freecount(cur);
1237	if (error)
1238		goto error0;
1239
1240	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1241	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1242	*inop = ino;
1243	return 0;
1244error1:
1245	xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1246error0:
1247	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1248	return error;
1249}
1250
1251/*
1252 * Use the free inode btree to allocate an inode based on distance from the
1253 * parent. Note that the provided cursor may be deleted and replaced.
1254 */
1255STATIC int
1256xfs_dialloc_ag_finobt_near(
1257	xfs_agino_t			pagino,
1258	struct xfs_btree_cur		**ocur,
1259	struct xfs_inobt_rec_incore	*rec)
1260{
1261	struct xfs_btree_cur		*lcur = *ocur;	/* left search cursor */
1262	struct xfs_btree_cur		*rcur;	/* right search cursor */
1263	struct xfs_inobt_rec_incore	rrec;
1264	int				error;
1265	int				i, j;
1266
1267	error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
1268	if (error)
1269		return error;
1270
1271	if (i == 1) {
1272		error = xfs_inobt_get_rec(lcur, rec, &i);
1273		if (error)
1274			return error;
1275		if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1))
1276			return -EFSCORRUPTED;
1277
1278		/*
1279		 * See if we've landed in the parent inode record. The finobt
1280		 * only tracks chunks with at least one free inode, so record
1281		 * existence is enough.
1282		 */
1283		if (pagino >= rec->ir_startino &&
1284		    pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
1285			return 0;
1286	}
1287
1288	error = xfs_btree_dup_cursor(lcur, &rcur);
1289	if (error)
1290		return error;
1291
1292	error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
1293	if (error)
1294		goto error_rcur;
1295	if (j == 1) {
1296		error = xfs_inobt_get_rec(rcur, &rrec, &j);
1297		if (error)
1298			goto error_rcur;
1299		if (XFS_IS_CORRUPT(lcur->bc_mp, j != 1)) {
1300			error = -EFSCORRUPTED;
1301			goto error_rcur;
1302		}
1303	}
1304
1305	if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1 && j != 1)) {
1306		error = -EFSCORRUPTED;
1307		goto error_rcur;
1308	}
1309	if (i == 1 && j == 1) {
1310		/*
1311		 * Both the left and right records are valid. Choose the closer
1312		 * inode chunk to the target.
1313		 */
1314		if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
1315		    (rrec.ir_startino - pagino)) {
1316			*rec = rrec;
1317			xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1318			*ocur = rcur;
1319		} else {
1320			xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1321		}
1322	} else if (j == 1) {
1323		/* only the right record is valid */
1324		*rec = rrec;
1325		xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1326		*ocur = rcur;
1327	} else if (i == 1) {
1328		/* only the left record is valid */
1329		xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1330	}
1331
1332	return 0;
1333
1334error_rcur:
1335	xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
1336	return error;
1337}
1338
1339/*
1340 * Use the free inode btree to find a free inode based on a newino hint. If
1341 * the hint is NULL, find the first free inode in the AG.
1342 */
1343STATIC int
1344xfs_dialloc_ag_finobt_newino(
1345	struct xfs_agi			*agi,
1346	struct xfs_btree_cur		*cur,
1347	struct xfs_inobt_rec_incore	*rec)
1348{
1349	int error;
1350	int i;
1351
1352	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1353		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1354					 XFS_LOOKUP_EQ, &i);
1355		if (error)
1356			return error;
1357		if (i == 1) {
1358			error = xfs_inobt_get_rec(cur, rec, &i);
1359			if (error)
1360				return error;
1361			if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1362				return -EFSCORRUPTED;
1363			return 0;
1364		}
1365	}
1366
1367	/*
1368	 * Find the first inode available in the AG.
1369	 */
1370	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1371	if (error)
1372		return error;
1373	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1374		return -EFSCORRUPTED;
1375
1376	error = xfs_inobt_get_rec(cur, rec, &i);
1377	if (error)
1378		return error;
1379	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1380		return -EFSCORRUPTED;
1381
1382	return 0;
1383}
1384
1385/*
1386 * Update the inobt based on a modification made to the finobt. Also ensure that
1387 * the records from both trees are equivalent post-modification.
1388 */
1389STATIC int
1390xfs_dialloc_ag_update_inobt(
1391	struct xfs_btree_cur		*cur,	/* inobt cursor */
1392	struct xfs_inobt_rec_incore	*frec,	/* finobt record */
1393	int				offset) /* inode offset */
1394{
1395	struct xfs_inobt_rec_incore	rec;
1396	int				error;
1397	int				i;
1398
1399	error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
1400	if (error)
1401		return error;
1402	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1403		return -EFSCORRUPTED;
1404
1405	error = xfs_inobt_get_rec(cur, &rec, &i);
1406	if (error)
1407		return error;
1408	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1409		return -EFSCORRUPTED;
1410	ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
1411				   XFS_INODES_PER_CHUNK) == 0);
1412
1413	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1414	rec.ir_freecount--;
1415
1416	if (XFS_IS_CORRUPT(cur->bc_mp,
1417			   rec.ir_free != frec->ir_free ||
1418			   rec.ir_freecount != frec->ir_freecount))
1419		return -EFSCORRUPTED;
1420
1421	return xfs_inobt_update(cur, &rec);
1422}
1423
1424/*
1425 * Allocate an inode using the free inode btree, if available. Otherwise, fall
1426 * back to the inobt search algorithm.
1427 *
1428 * The caller selected an AG for us, and made sure that free inodes are
1429 * available.
1430 */
1431static int
1432xfs_dialloc_ag(
 
1433	struct xfs_trans	*tp,
1434	struct xfs_buf		*agbp,
1435	struct xfs_perag	*pag,
1436	xfs_ino_t		parent,
1437	xfs_ino_t		*inop)
1438{
1439	struct xfs_mount		*mp = tp->t_mountp;
1440	struct xfs_agi			*agi = agbp->b_addr;
1441	xfs_agnumber_t			pagno = XFS_INO_TO_AGNO(mp, parent);
1442	xfs_agino_t			pagino = XFS_INO_TO_AGINO(mp, parent);
1443	struct xfs_btree_cur		*cur;	/* finobt cursor */
1444	struct xfs_btree_cur		*icur;	/* inobt cursor */
1445	struct xfs_inobt_rec_incore	rec;
1446	xfs_ino_t			ino;
1447	int				error;
1448	int				offset;
1449	int				i;
1450
1451	if (!xfs_sb_version_hasfinobt(&mp->m_sb))
1452		return xfs_dialloc_ag_inobt(tp, agbp, pag, parent, inop);
1453
1454	/*
1455	 * If pagino is 0 (this is the root inode allocation) use newino.
1456	 * This must work because we've just allocated some.
1457	 */
1458	if (!pagino)
1459		pagino = be32_to_cpu(agi->agi_newino);
1460
1461	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_FINO);
1462
1463	error = xfs_check_agi_freecount(cur);
1464	if (error)
1465		goto error_cur;
1466
1467	/*
1468	 * The search algorithm depends on whether we're in the same AG as the
1469	 * parent. If so, find the closest available inode to the parent. If
1470	 * not, consider the agi hint or find the first free inode in the AG.
1471	 */
1472	if (pag->pag_agno == pagno)
1473		error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
1474	else
1475		error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
1476	if (error)
1477		goto error_cur;
1478
1479	offset = xfs_inobt_first_free_inode(&rec);
1480	ASSERT(offset >= 0);
1481	ASSERT(offset < XFS_INODES_PER_CHUNK);
1482	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1483				   XFS_INODES_PER_CHUNK) == 0);
1484	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1485
1486	/*
1487	 * Modify or remove the finobt record.
1488	 */
1489	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1490	rec.ir_freecount--;
1491	if (rec.ir_freecount)
1492		error = xfs_inobt_update(cur, &rec);
1493	else
1494		error = xfs_btree_delete(cur, &i);
1495	if (error)
1496		goto error_cur;
1497
1498	/*
1499	 * The finobt has now been updated appropriately. We haven't updated the
1500	 * agi and superblock yet, so we can create an inobt cursor and validate
1501	 * the original freecount. If all is well, make the equivalent update to
1502	 * the inobt using the finobt record and offset information.
1503	 */
1504	icur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1505
1506	error = xfs_check_agi_freecount(icur);
1507	if (error)
1508		goto error_icur;
1509
1510	error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
1511	if (error)
1512		goto error_icur;
1513
1514	/*
1515	 * Both trees have now been updated. We must update the perag and
1516	 * superblock before we can check the freecount for each btree.
1517	 */
1518	be32_add_cpu(&agi->agi_freecount, -1);
1519	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1520	pag->pagi_freecount--;
1521
1522	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1523
1524	error = xfs_check_agi_freecount(icur);
1525	if (error)
1526		goto error_icur;
1527	error = xfs_check_agi_freecount(cur);
1528	if (error)
1529		goto error_icur;
1530
1531	xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
1532	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1533	*inop = ino;
1534	return 0;
1535
1536error_icur:
1537	xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
1538error_cur:
1539	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1540	return error;
1541}
1542
1543static int
1544xfs_dialloc_roll(
1545	struct xfs_trans	**tpp,
1546	struct xfs_buf		*agibp)
1547{
1548	struct xfs_trans	*tp = *tpp;
1549	struct xfs_dquot_acct	*dqinfo;
1550	int			error;
1551
1552	/*
1553	 * Hold to on to the agibp across the commit so no other allocation can
1554	 * come in and take the free inodes we just allocated for our caller.
1555	 */
1556	xfs_trans_bhold(tp, agibp);
1557
1558	/*
1559	 * We want the quota changes to be associated with the next transaction,
1560	 * NOT this one. So, detach the dqinfo from this and attach it to the
1561	 * next transaction.
1562	 */
1563	dqinfo = tp->t_dqinfo;
1564	tp->t_dqinfo = NULL;
1565
1566	error = xfs_trans_roll(&tp);
1567
1568	/* Re-attach the quota info that we detached from prev trx. */
1569	tp->t_dqinfo = dqinfo;
1570
1571	/*
1572	 * Join the buffer even on commit error so that the buffer is released
1573	 * when the caller cancels the transaction and doesn't have to handle
1574	 * this error case specially.
1575	 */
1576	xfs_trans_bjoin(tp, agibp);
1577	*tpp = tp;
1578	return error;
1579}
1580
1581static xfs_agnumber_t
1582xfs_ialloc_next_ag(
1583	xfs_mount_t	*mp)
1584{
1585	xfs_agnumber_t	agno;
1586
1587	spin_lock(&mp->m_agirotor_lock);
1588	agno = mp->m_agirotor;
1589	if (++mp->m_agirotor >= mp->m_maxagi)
1590		mp->m_agirotor = 0;
1591	spin_unlock(&mp->m_agirotor_lock);
1592
1593	return agno;
1594}
1595
1596static bool
1597xfs_dialloc_good_ag(
 
1598	struct xfs_trans	*tp,
1599	struct xfs_perag	*pag,
1600	umode_t			mode,
1601	int			flags,
1602	bool			ok_alloc)
1603{
1604	struct xfs_mount	*mp = tp->t_mountp;
1605	xfs_extlen_t		ineed;
1606	xfs_extlen_t		longest = 0;
1607	int			needspace;
1608	int			error;
1609
1610	if (!pag->pagi_inodeok)
 
 
1611		return false;
1612
1613	if (!pag->pagi_init) {
1614		error = xfs_ialloc_pagi_init(mp, tp, pag->pag_agno);
1615		if (error)
1616			return false;
1617	}
1618
1619	if (pag->pagi_freecount)
1620		return true;
1621	if (!ok_alloc)
1622		return false;
1623
1624	if (!pag->pagf_init) {
1625		error = xfs_alloc_pagf_init(mp, tp, pag->pag_agno, flags);
1626		if (error)
1627			return false;
1628	}
1629
1630	/*
1631	 * Check that there is enough free space for the file plus a chunk of
1632	 * inodes if we need to allocate some. If this is the first pass across
1633	 * the AGs, take into account the potential space needed for alignment
1634	 * of inode chunks when checking the longest contiguous free space in
1635	 * the AG - this prevents us from getting ENOSPC because we have free
1636	 * space larger than ialloc_blks but alignment constraints prevent us
1637	 * from using it.
1638	 *
1639	 * If we can't find an AG with space for full alignment slack to be
1640	 * taken into account, we must be near ENOSPC in all AGs.  Hence we
1641	 * don't include alignment for the second pass and so if we fail
1642	 * allocation due to alignment issues then it is most likely a real
1643	 * ENOSPC condition.
1644	 *
1645	 * XXX(dgc): this calculation is now bogus thanks to the per-ag
1646	 * reservations that xfs_alloc_fix_freelist() now does via
1647	 * xfs_alloc_space_available(). When the AG fills up, pagf_freeblks will
1648	 * be more than large enough for the check below to succeed, but
1649	 * xfs_alloc_space_available() will fail because of the non-zero
1650	 * metadata reservation and hence we won't actually be able to allocate
1651	 * more inodes in this AG. We do soooo much unnecessary work near ENOSPC
1652	 * because of this.
1653	 */
1654	ineed = M_IGEO(mp)->ialloc_min_blks;
1655	if (flags && ineed > 1)
1656		ineed += M_IGEO(mp)->cluster_align;
1657	longest = pag->pagf_longest;
1658	if (!longest)
1659		longest = pag->pagf_flcount > 0;
1660	needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
1661
1662	if (pag->pagf_freeblks < needspace + ineed || longest < ineed)
1663		return false;
1664	return true;
1665}
1666
1667static int
1668xfs_dialloc_try_ag(
 
1669	struct xfs_trans	**tpp,
1670	struct xfs_perag	*pag,
1671	xfs_ino_t		parent,
1672	xfs_ino_t		*new_ino,
1673	bool			ok_alloc)
1674{
1675	struct xfs_buf		*agbp;
1676	xfs_ino_t		ino;
1677	int			error;
1678
1679	/*
1680	 * Then read in the AGI buffer and recheck with the AGI buffer
1681	 * lock held.
1682	 */
1683	error = xfs_ialloc_read_agi(pag->pag_mount, *tpp, pag->pag_agno, &agbp);
1684	if (error)
1685		return error;
1686
1687	if (!pag->pagi_freecount) {
1688		if (!ok_alloc) {
1689			error = -EAGAIN;
1690			goto out_release;
1691		}
1692
1693		error = xfs_ialloc_ag_alloc(*tpp, agbp, pag);
1694		if (error < 0)
1695			goto out_release;
1696
1697		/*
1698		 * We successfully allocated space for an inode cluster in this
1699		 * AG.  Roll the transaction so that we can allocate one of the
1700		 * new inodes.
1701		 */
1702		ASSERT(pag->pagi_freecount > 0);
1703		error = xfs_dialloc_roll(tpp, agbp);
1704		if (error)
1705			goto out_release;
1706	}
1707
1708	/* Allocate an inode in the found AG */
1709	error = xfs_dialloc_ag(*tpp, agbp, pag, parent, &ino);
1710	if (!error)
1711		*new_ino = ino;
1712	return error;
1713
1714out_release:
1715	xfs_trans_brelse(*tpp, agbp);
1716	return error;
1717}
1718
1719/*
1720 * Allocate an on-disk inode.
1721 *
1722 * Mode is used to tell whether the new inode is a directory and hence where to
1723 * locate it. The on-disk inode that is allocated will be returned in @new_ino
1724 * on success, otherwise an error will be set to indicate the failure (e.g.
1725 * -ENOSPC).
1726 */
1727int
1728xfs_dialloc(
1729	struct xfs_trans	**tpp,
1730	xfs_ino_t		parent,
1731	umode_t			mode,
1732	xfs_ino_t		*new_ino)
1733{
1734	struct xfs_mount	*mp = (*tpp)->t_mountp;
1735	xfs_agnumber_t		agno;
1736	int			error = 0;
1737	xfs_agnumber_t		start_agno;
1738	struct xfs_perag	*pag;
1739	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
1740	bool			ok_alloc = true;
 
1741	int			flags;
1742	xfs_ino_t		ino;
1743
1744	/*
1745	 * Directories, symlinks, and regular files frequently allocate at least
1746	 * one block, so factor that potential expansion when we examine whether
1747	 * an AG has enough space for file creation.
1748	 */
1749	if (S_ISDIR(mode))
1750		start_agno = xfs_ialloc_next_ag(mp);
 
1751	else {
1752		start_agno = XFS_INO_TO_AGNO(mp, parent);
1753		if (start_agno >= mp->m_maxagi)
1754			start_agno = 0;
1755	}
1756
1757	/*
1758	 * If we have already hit the ceiling of inode blocks then clear
1759	 * ok_alloc so we scan all available agi structures for a free
1760	 * inode.
1761	 *
1762	 * Read rough value of mp->m_icount by percpu_counter_read_positive,
1763	 * which will sacrifice the preciseness but improve the performance.
1764	 */
1765	if (igeo->maxicount &&
1766	    percpu_counter_read_positive(&mp->m_icount) + igeo->ialloc_inos
1767							> igeo->maxicount) {
1768		ok_alloc = false;
1769	}
1770
1771	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1772	 * Loop until we find an allocation group that either has free inodes
1773	 * or in which we can allocate some inodes.  Iterate through the
1774	 * allocation groups upward, wrapping at the end.
1775	 */
1776	agno = start_agno;
1777	flags = XFS_ALLOC_FLAG_TRYLOCK;
1778	for (;;) {
1779		pag = xfs_perag_get(mp, agno);
1780		if (xfs_dialloc_good_ag(*tpp, pag, mode, flags, ok_alloc)) {
1781			error = xfs_dialloc_try_ag(tpp, pag, parent,
1782					&ino, ok_alloc);
1783			if (error != -EAGAIN)
1784				break;
 
1785		}
1786
1787		if (XFS_FORCED_SHUTDOWN(mp)) {
1788			error = -EFSCORRUPTED;
1789			break;
1790		}
1791		if (++agno == mp->m_maxagi)
1792			agno = 0;
1793		if (agno == start_agno) {
1794			if (!flags) {
1795				error = -ENOSPC;
1796				break;
1797			}
1798			flags = 0;
 
 
 
1799		}
1800		xfs_perag_put(pag);
1801	}
1802
1803	if (!error)
1804		*new_ino = ino;
1805	xfs_perag_put(pag);
1806	return error;
1807}
1808
1809/*
1810 * Free the blocks of an inode chunk. We must consider that the inode chunk
1811 * might be sparse and only free the regions that are allocated as part of the
1812 * chunk.
1813 */
1814STATIC void
1815xfs_difree_inode_chunk(
1816	struct xfs_trans		*tp,
1817	xfs_agnumber_t			agno,
1818	struct xfs_inobt_rec_incore	*rec)
1819{
1820	struct xfs_mount		*mp = tp->t_mountp;
1821	xfs_agblock_t			sagbno = XFS_AGINO_TO_AGBNO(mp,
1822							rec->ir_startino);
1823	int				startidx, endidx;
1824	int				nextbit;
1825	xfs_agblock_t			agbno;
1826	int				contigblk;
1827	DECLARE_BITMAP(holemask, XFS_INOBT_HOLEMASK_BITS);
1828
1829	if (!xfs_inobt_issparse(rec->ir_holemask)) {
1830		/* not sparse, calculate extent info directly */
1831		xfs_bmap_add_free(tp, XFS_AGB_TO_FSB(mp, agno, sagbno),
1832				  M_IGEO(mp)->ialloc_blks,
1833				  &XFS_RMAP_OINFO_INODES);
1834		return;
1835	}
1836
1837	/* holemask is only 16-bits (fits in an unsigned long) */
1838	ASSERT(sizeof(rec->ir_holemask) <= sizeof(holemask[0]));
1839	holemask[0] = rec->ir_holemask;
1840
1841	/*
1842	 * Find contiguous ranges of zeroes (i.e., allocated regions) in the
1843	 * holemask and convert the start/end index of each range to an extent.
1844	 * We start with the start and end index both pointing at the first 0 in
1845	 * the mask.
1846	 */
1847	startidx = endidx = find_first_zero_bit(holemask,
1848						XFS_INOBT_HOLEMASK_BITS);
1849	nextbit = startidx + 1;
1850	while (startidx < XFS_INOBT_HOLEMASK_BITS) {
 
 
1851		nextbit = find_next_zero_bit(holemask, XFS_INOBT_HOLEMASK_BITS,
1852					     nextbit);
1853		/*
1854		 * If the next zero bit is contiguous, update the end index of
1855		 * the current range and continue.
1856		 */
1857		if (nextbit != XFS_INOBT_HOLEMASK_BITS &&
1858		    nextbit == endidx + 1) {
1859			endidx = nextbit;
1860			goto next;
1861		}
1862
1863		/*
1864		 * nextbit is not contiguous with the current end index. Convert
1865		 * the current start/end to an extent and add it to the free
1866		 * list.
1867		 */
1868		agbno = sagbno + (startidx * XFS_INODES_PER_HOLEMASK_BIT) /
1869				  mp->m_sb.sb_inopblock;
1870		contigblk = ((endidx - startidx + 1) *
1871			     XFS_INODES_PER_HOLEMASK_BIT) /
1872			    mp->m_sb.sb_inopblock;
1873
1874		ASSERT(agbno % mp->m_sb.sb_spino_align == 0);
1875		ASSERT(contigblk % mp->m_sb.sb_spino_align == 0);
1876		xfs_bmap_add_free(tp, XFS_AGB_TO_FSB(mp, agno, agbno),
1877				  contigblk, &XFS_RMAP_OINFO_INODES);
 
 
 
 
1878
1879		/* reset range to current bit and carry on... */
1880		startidx = endidx = nextbit;
1881
1882next:
1883		nextbit++;
1884	}
 
1885}
1886
1887STATIC int
1888xfs_difree_inobt(
1889	struct xfs_mount		*mp,
1890	struct xfs_trans		*tp,
1891	struct xfs_buf			*agbp,
1892	struct xfs_perag		*pag,
1893	xfs_agino_t			agino,
1894	struct xfs_icluster		*xic,
1895	struct xfs_inobt_rec_incore	*orec)
1896{
 
1897	struct xfs_agi			*agi = agbp->b_addr;
1898	struct xfs_btree_cur		*cur;
1899	struct xfs_inobt_rec_incore	rec;
1900	int				ilen;
1901	int				error;
1902	int				i;
1903	int				off;
1904
1905	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1906	ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
1907
1908	/*
1909	 * Initialize the cursor.
1910	 */
1911	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1912
1913	error = xfs_check_agi_freecount(cur);
1914	if (error)
1915		goto error0;
1916
1917	/*
1918	 * Look for the entry describing this inode.
1919	 */
1920	if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1921		xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1922			__func__, error);
1923		goto error0;
1924	}
1925	if (XFS_IS_CORRUPT(mp, i != 1)) {
1926		error = -EFSCORRUPTED;
1927		goto error0;
1928	}
1929	error = xfs_inobt_get_rec(cur, &rec, &i);
1930	if (error) {
1931		xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1932			__func__, error);
1933		goto error0;
1934	}
1935	if (XFS_IS_CORRUPT(mp, i != 1)) {
1936		error = -EFSCORRUPTED;
1937		goto error0;
1938	}
1939	/*
1940	 * Get the offset in the inode chunk.
1941	 */
1942	off = agino - rec.ir_startino;
1943	ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1944	ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1945	/*
1946	 * Mark the inode free & increment the count.
1947	 */
1948	rec.ir_free |= XFS_INOBT_MASK(off);
1949	rec.ir_freecount++;
1950
1951	/*
1952	 * When an inode chunk is free, it becomes eligible for removal. Don't
1953	 * remove the chunk if the block size is large enough for multiple inode
1954	 * chunks (that might not be free).
1955	 */
1956	if (!(mp->m_flags & XFS_MOUNT_IKEEP) &&
1957	    rec.ir_free == XFS_INOBT_ALL_FREE &&
1958	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
1959		struct xfs_perag	*pag = agbp->b_pag;
1960
1961		xic->deleted = true;
1962		xic->first_ino = XFS_AGINO_TO_INO(mp, pag->pag_agno,
1963				rec.ir_startino);
1964		xic->alloc = xfs_inobt_irec_to_allocmask(&rec);
1965
1966		/*
1967		 * Remove the inode cluster from the AGI B+Tree, adjust the
1968		 * AGI and Superblock inode counts, and mark the disk space
1969		 * to be freed when the transaction is committed.
1970		 */
1971		ilen = rec.ir_freecount;
1972		be32_add_cpu(&agi->agi_count, -ilen);
1973		be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
1974		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
1975		pag->pagi_freecount -= ilen - 1;
1976		pag->pagi_count -= ilen;
1977		xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
1978		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
1979
1980		if ((error = xfs_btree_delete(cur, &i))) {
1981			xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
1982				__func__, error);
1983			goto error0;
1984		}
1985
1986		xfs_difree_inode_chunk(tp, pag->pag_agno, &rec);
 
 
1987	} else {
1988		xic->deleted = false;
1989
1990		error = xfs_inobt_update(cur, &rec);
1991		if (error) {
1992			xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
1993				__func__, error);
1994			goto error0;
1995		}
1996
1997		/* 
1998		 * Change the inode free counts and log the ag/sb changes.
1999		 */
2000		be32_add_cpu(&agi->agi_freecount, 1);
2001		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
2002		pag->pagi_freecount++;
2003		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
2004	}
2005
2006	error = xfs_check_agi_freecount(cur);
2007	if (error)
2008		goto error0;
2009
2010	*orec = rec;
2011	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2012	return 0;
2013
2014error0:
2015	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2016	return error;
2017}
2018
2019/*
2020 * Free an inode in the free inode btree.
2021 */
2022STATIC int
2023xfs_difree_finobt(
2024	struct xfs_mount		*mp,
2025	struct xfs_trans		*tp,
2026	struct xfs_buf			*agbp,
2027	struct xfs_perag		*pag,
2028	xfs_agino_t			agino,
2029	struct xfs_inobt_rec_incore	*ibtrec) /* inobt record */
2030{
 
2031	struct xfs_btree_cur		*cur;
2032	struct xfs_inobt_rec_incore	rec;
2033	int				offset = agino - ibtrec->ir_startino;
2034	int				error;
2035	int				i;
2036
2037	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_FINO);
2038
2039	error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
2040	if (error)
2041		goto error;
2042	if (i == 0) {
2043		/*
2044		 * If the record does not exist in the finobt, we must have just
2045		 * freed an inode in a previously fully allocated chunk. If not,
2046		 * something is out of sync.
2047		 */
2048		if (XFS_IS_CORRUPT(mp, ibtrec->ir_freecount != 1)) {
2049			error = -EFSCORRUPTED;
2050			goto error;
2051		}
2052
2053		error = xfs_inobt_insert_rec(cur, ibtrec->ir_holemask,
2054					     ibtrec->ir_count,
2055					     ibtrec->ir_freecount,
2056					     ibtrec->ir_free, &i);
2057		if (error)
2058			goto error;
2059		ASSERT(i == 1);
2060
2061		goto out;
2062	}
2063
2064	/*
2065	 * Read and update the existing record. We could just copy the ibtrec
2066	 * across here, but that would defeat the purpose of having redundant
2067	 * metadata. By making the modifications independently, we can catch
2068	 * corruptions that we wouldn't see if we just copied from one record
2069	 * to another.
2070	 */
2071	error = xfs_inobt_get_rec(cur, &rec, &i);
2072	if (error)
2073		goto error;
2074	if (XFS_IS_CORRUPT(mp, i != 1)) {
2075		error = -EFSCORRUPTED;
2076		goto error;
2077	}
2078
2079	rec.ir_free |= XFS_INOBT_MASK(offset);
2080	rec.ir_freecount++;
2081
2082	if (XFS_IS_CORRUPT(mp,
2083			   rec.ir_free != ibtrec->ir_free ||
2084			   rec.ir_freecount != ibtrec->ir_freecount)) {
2085		error = -EFSCORRUPTED;
2086		goto error;
2087	}
2088
2089	/*
2090	 * The content of inobt records should always match between the inobt
2091	 * and finobt. The lifecycle of records in the finobt is different from
2092	 * the inobt in that the finobt only tracks records with at least one
2093	 * free inode. Hence, if all of the inodes are free and we aren't
2094	 * keeping inode chunks permanently on disk, remove the record.
2095	 * Otherwise, update the record with the new information.
2096	 *
2097	 * Note that we currently can't free chunks when the block size is large
2098	 * enough for multiple chunks. Leave the finobt record to remain in sync
2099	 * with the inobt.
2100	 */
2101	if (rec.ir_free == XFS_INOBT_ALL_FREE &&
2102	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK &&
2103	    !(mp->m_flags & XFS_MOUNT_IKEEP)) {
2104		error = xfs_btree_delete(cur, &i);
2105		if (error)
2106			goto error;
2107		ASSERT(i == 1);
2108	} else {
2109		error = xfs_inobt_update(cur, &rec);
2110		if (error)
2111			goto error;
2112	}
2113
2114out:
2115	error = xfs_check_agi_freecount(cur);
2116	if (error)
2117		goto error;
2118
2119	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2120	return 0;
2121
2122error:
2123	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2124	return error;
2125}
2126
2127/*
2128 * Free disk inode.  Carefully avoids touching the incore inode, all
2129 * manipulations incore are the caller's responsibility.
2130 * The on-disk inode is not changed by this operation, only the
2131 * btree (free inode mask) is changed.
2132 */
2133int
2134xfs_difree(
2135	struct xfs_trans	*tp,
2136	struct xfs_perag	*pag,
2137	xfs_ino_t		inode,
2138	struct xfs_icluster	*xic)
2139{
2140	/* REFERENCED */
2141	xfs_agblock_t		agbno;	/* block number containing inode */
2142	struct xfs_buf		*agbp;	/* buffer for allocation group header */
2143	xfs_agino_t		agino;	/* allocation group inode number */
2144	int			error;	/* error return value */
2145	struct xfs_mount	*mp = tp->t_mountp;
2146	struct xfs_inobt_rec_incore rec;/* btree record */
2147
2148	/*
2149	 * Break up inode number into its components.
2150	 */
2151	if (pag->pag_agno != XFS_INO_TO_AGNO(mp, inode)) {
2152		xfs_warn(mp, "%s: agno != pag->pag_agno (%d != %d).",
2153			__func__, XFS_INO_TO_AGNO(mp, inode), pag->pag_agno);
2154		ASSERT(0);
2155		return -EINVAL;
2156	}
2157	agino = XFS_INO_TO_AGINO(mp, inode);
2158	if (inode != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino))  {
2159		xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
2160			__func__, (unsigned long long)inode,
2161			(unsigned long long)XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2162		ASSERT(0);
2163		return -EINVAL;
2164	}
2165	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2166	if (agbno >= mp->m_sb.sb_agblocks)  {
2167		xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
2168			__func__, agbno, mp->m_sb.sb_agblocks);
2169		ASSERT(0);
2170		return -EINVAL;
2171	}
2172	/*
2173	 * Get the allocation group header.
2174	 */
2175	error = xfs_ialloc_read_agi(mp, tp, pag->pag_agno, &agbp);
2176	if (error) {
2177		xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
2178			__func__, error);
2179		return error;
2180	}
2181
2182	/*
2183	 * Fix up the inode allocation btree.
2184	 */
2185	error = xfs_difree_inobt(mp, tp, agbp, pag, agino, xic, &rec);
2186	if (error)
2187		goto error0;
2188
2189	/*
2190	 * Fix up the free inode btree.
2191	 */
2192	if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
2193		error = xfs_difree_finobt(mp, tp, agbp, pag, agino, &rec);
2194		if (error)
2195			goto error0;
2196	}
2197
2198	return 0;
2199
2200error0:
2201	return error;
2202}
2203
2204STATIC int
2205xfs_imap_lookup(
2206	struct xfs_mount	*mp,
2207	struct xfs_trans	*tp,
2208	struct xfs_perag	*pag,
2209	xfs_agino_t		agino,
2210	xfs_agblock_t		agbno,
2211	xfs_agblock_t		*chunk_agbno,
2212	xfs_agblock_t		*offset_agbno,
2213	int			flags)
2214{
 
2215	struct xfs_inobt_rec_incore rec;
2216	struct xfs_btree_cur	*cur;
2217	struct xfs_buf		*agbp;
2218	int			error;
2219	int			i;
2220
2221	error = xfs_ialloc_read_agi(mp, tp, pag->pag_agno, &agbp);
2222	if (error) {
2223		xfs_alert(mp,
2224			"%s: xfs_ialloc_read_agi() returned error %d, agno %d",
2225			__func__, error, pag->pag_agno);
2226		return error;
2227	}
2228
2229	/*
2230	 * Lookup the inode record for the given agino. If the record cannot be
2231	 * found, then it's an invalid inode number and we should abort. Once
2232	 * we have a record, we need to ensure it contains the inode number
2233	 * we are looking up.
2234	 */
2235	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
2236	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
2237	if (!error) {
2238		if (i)
2239			error = xfs_inobt_get_rec(cur, &rec, &i);
2240		if (!error && i == 0)
2241			error = -EINVAL;
2242	}
2243
2244	xfs_trans_brelse(tp, agbp);
2245	xfs_btree_del_cursor(cur, error);
2246	if (error)
2247		return error;
2248
2249	/* check that the returned record contains the required inode */
2250	if (rec.ir_startino > agino ||
2251	    rec.ir_startino + M_IGEO(mp)->ialloc_inos <= agino)
2252		return -EINVAL;
2253
2254	/* for untrusted inodes check it is allocated first */
2255	if ((flags & XFS_IGET_UNTRUSTED) &&
2256	    (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
2257		return -EINVAL;
2258
2259	*chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
2260	*offset_agbno = agbno - *chunk_agbno;
2261	return 0;
2262}
2263
2264/*
2265 * Return the location of the inode in imap, for mapping it into a buffer.
2266 */
2267int
2268xfs_imap(
2269	struct xfs_mount	 *mp,	/* file system mount structure */
2270	struct xfs_trans	 *tp,	/* transaction pointer */
2271	xfs_ino_t		ino,	/* inode to locate */
2272	struct xfs_imap		*imap,	/* location map structure */
2273	uint			flags)	/* flags for inode btree lookup */
2274{
 
2275	xfs_agblock_t		agbno;	/* block number of inode in the alloc group */
2276	xfs_agino_t		agino;	/* inode number within alloc group */
2277	xfs_agblock_t		chunk_agbno;	/* first block in inode chunk */
2278	xfs_agblock_t		cluster_agbno;	/* first block in inode cluster */
2279	int			error;	/* error code */
2280	int			offset;	/* index of inode in its buffer */
2281	xfs_agblock_t		offset_agbno;	/* blks from chunk start to inode */
2282	struct xfs_perag	*pag;
2283
2284	ASSERT(ino != NULLFSINO);
2285
2286	/*
2287	 * Split up the inode number into its parts.
2288	 */
2289	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ino));
2290	agino = XFS_INO_TO_AGINO(mp, ino);
2291	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2292	if (!pag || agbno >= mp->m_sb.sb_agblocks ||
2293	    ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2294		error = -EINVAL;
2295#ifdef DEBUG
2296		/*
2297		 * Don't output diagnostic information for untrusted inodes
2298		 * as they can be invalid without implying corruption.
2299		 */
2300		if (flags & XFS_IGET_UNTRUSTED)
2301			goto out_drop;
2302		if (!pag) {
2303			xfs_alert(mp,
2304				"%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
2305				__func__, XFS_INO_TO_AGNO(mp, ino),
2306				mp->m_sb.sb_agcount);
2307		}
2308		if (agbno >= mp->m_sb.sb_agblocks) {
2309			xfs_alert(mp,
2310		"%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
2311				__func__, (unsigned long long)agbno,
2312				(unsigned long)mp->m_sb.sb_agblocks);
2313		}
2314		if (pag && ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2315			xfs_alert(mp,
2316		"%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
2317				__func__, ino,
2318				XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2319		}
2320		xfs_stack_trace();
2321#endif /* DEBUG */
2322		goto out_drop;
2323	}
2324
2325	/*
2326	 * For bulkstat and handle lookups, we have an untrusted inode number
2327	 * that we have to verify is valid. We cannot do this just by reading
2328	 * the inode buffer as it may have been unlinked and removed leaving
2329	 * inodes in stale state on disk. Hence we have to do a btree lookup
2330	 * in all cases where an untrusted inode number is passed.
2331	 */
2332	if (flags & XFS_IGET_UNTRUSTED) {
2333		error = xfs_imap_lookup(mp, tp, pag, agino, agbno,
2334					&chunk_agbno, &offset_agbno, flags);
2335		if (error)
2336			goto out_drop;
2337		goto out_map;
2338	}
2339
2340	/*
2341	 * If the inode cluster size is the same as the blocksize or
2342	 * smaller we get to the buffer by simple arithmetics.
2343	 */
2344	if (M_IGEO(mp)->blocks_per_cluster == 1) {
2345		offset = XFS_INO_TO_OFFSET(mp, ino);
2346		ASSERT(offset < mp->m_sb.sb_inopblock);
2347
2348		imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, agbno);
2349		imap->im_len = XFS_FSB_TO_BB(mp, 1);
2350		imap->im_boffset = (unsigned short)(offset <<
2351							mp->m_sb.sb_inodelog);
2352		error = 0;
2353		goto out_drop;
2354	}
2355
2356	/*
2357	 * If the inode chunks are aligned then use simple maths to
2358	 * find the location. Otherwise we have to do a btree
2359	 * lookup to find the location.
2360	 */
2361	if (M_IGEO(mp)->inoalign_mask) {
2362		offset_agbno = agbno & M_IGEO(mp)->inoalign_mask;
2363		chunk_agbno = agbno - offset_agbno;
2364	} else {
2365		error = xfs_imap_lookup(mp, tp, pag, agino, agbno,
2366					&chunk_agbno, &offset_agbno, flags);
2367		if (error)
2368			goto out_drop;
2369	}
2370
2371out_map:
2372	ASSERT(agbno >= chunk_agbno);
2373	cluster_agbno = chunk_agbno +
2374		((offset_agbno / M_IGEO(mp)->blocks_per_cluster) *
2375		 M_IGEO(mp)->blocks_per_cluster);
2376	offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
2377		XFS_INO_TO_OFFSET(mp, ino);
2378
2379	imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, cluster_agbno);
2380	imap->im_len = XFS_FSB_TO_BB(mp, M_IGEO(mp)->blocks_per_cluster);
2381	imap->im_boffset = (unsigned short)(offset << mp->m_sb.sb_inodelog);
2382
2383	/*
2384	 * If the inode number maps to a block outside the bounds
2385	 * of the file system then return NULL rather than calling
2386	 * read_buf and panicing when we get an error from the
2387	 * driver.
2388	 */
2389	if ((imap->im_blkno + imap->im_len) >
2390	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
2391		xfs_alert(mp,
2392	"%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
2393			__func__, (unsigned long long) imap->im_blkno,
2394			(unsigned long long) imap->im_len,
2395			XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
2396		error = -EINVAL;
2397		goto out_drop;
2398	}
2399	error = 0;
2400out_drop:
2401	if (pag)
2402		xfs_perag_put(pag);
2403	return error;
2404}
2405
2406/*
2407 * Log specified fields for the ag hdr (inode section). The growth of the agi
2408 * structure over time requires that we interpret the buffer as two logical
2409 * regions delineated by the end of the unlinked list. This is due to the size
2410 * of the hash table and its location in the middle of the agi.
2411 *
2412 * For example, a request to log a field before agi_unlinked and a field after
2413 * agi_unlinked could cause us to log the entire hash table and use an excessive
2414 * amount of log space. To avoid this behavior, log the region up through
2415 * agi_unlinked in one call and the region after agi_unlinked through the end of
2416 * the structure in another.
2417 */
2418void
2419xfs_ialloc_log_agi(
2420	xfs_trans_t	*tp,		/* transaction pointer */
2421	struct xfs_buf	*bp,		/* allocation group header buffer */
2422	int		fields)		/* bitmask of fields to log */
2423{
2424	int			first;		/* first byte number */
2425	int			last;		/* last byte number */
2426	static const short	offsets[] = {	/* field starting offsets */
2427					/* keep in sync with bit definitions */
2428		offsetof(xfs_agi_t, agi_magicnum),
2429		offsetof(xfs_agi_t, agi_versionnum),
2430		offsetof(xfs_agi_t, agi_seqno),
2431		offsetof(xfs_agi_t, agi_length),
2432		offsetof(xfs_agi_t, agi_count),
2433		offsetof(xfs_agi_t, agi_root),
2434		offsetof(xfs_agi_t, agi_level),
2435		offsetof(xfs_agi_t, agi_freecount),
2436		offsetof(xfs_agi_t, agi_newino),
2437		offsetof(xfs_agi_t, agi_dirino),
2438		offsetof(xfs_agi_t, agi_unlinked),
2439		offsetof(xfs_agi_t, agi_free_root),
2440		offsetof(xfs_agi_t, agi_free_level),
2441		offsetof(xfs_agi_t, agi_iblocks),
2442		sizeof(xfs_agi_t)
2443	};
2444#ifdef DEBUG
2445	struct xfs_agi		*agi = bp->b_addr;
2446
2447	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2448#endif
2449
2450	/*
2451	 * Compute byte offsets for the first and last fields in the first
2452	 * region and log the agi buffer. This only logs up through
2453	 * agi_unlinked.
2454	 */
2455	if (fields & XFS_AGI_ALL_BITS_R1) {
2456		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
2457				  &first, &last);
2458		xfs_trans_log_buf(tp, bp, first, last);
2459	}
2460
2461	/*
2462	 * Mask off the bits in the first region and calculate the first and
2463	 * last field offsets for any bits in the second region.
2464	 */
2465	fields &= ~XFS_AGI_ALL_BITS_R1;
2466	if (fields) {
2467		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
2468				  &first, &last);
2469		xfs_trans_log_buf(tp, bp, first, last);
2470	}
2471}
2472
2473static xfs_failaddr_t
2474xfs_agi_verify(
2475	struct xfs_buf	*bp)
2476{
2477	struct xfs_mount *mp = bp->b_mount;
2478	struct xfs_agi	*agi = bp->b_addr;
2479	int		i;
 
 
 
2480
2481	if (xfs_sb_version_hascrc(&mp->m_sb)) {
2482		if (!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid))
2483			return __this_address;
2484		if (!xfs_log_check_lsn(mp, be64_to_cpu(agi->agi_lsn)))
2485			return __this_address;
2486	}
2487
2488	/*
2489	 * Validate the magic number of the agi block.
2490	 */
2491	if (!xfs_verify_magic(bp, agi->agi_magicnum))
2492		return __this_address;
2493	if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
2494		return __this_address;
2495
 
 
 
 
2496	if (be32_to_cpu(agi->agi_level) < 1 ||
2497	    be32_to_cpu(agi->agi_level) > M_IGEO(mp)->inobt_maxlevels)
2498		return __this_address;
2499
2500	if (xfs_sb_version_hasfinobt(&mp->m_sb) &&
2501	    (be32_to_cpu(agi->agi_free_level) < 1 ||
2502	     be32_to_cpu(agi->agi_free_level) > M_IGEO(mp)->inobt_maxlevels))
2503		return __this_address;
2504
2505	/*
2506	 * during growfs operations, the perag is not fully initialised,
2507	 * so we can't use it for any useful checking. growfs ensures we can't
2508	 * use it by using uncached buffers that don't have the perag attached
2509	 * so we can detect and avoid this problem.
2510	 */
2511	if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
2512		return __this_address;
2513
2514	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
2515		if (agi->agi_unlinked[i] == cpu_to_be32(NULLAGINO))
2516			continue;
2517		if (!xfs_verify_ino(mp, be32_to_cpu(agi->agi_unlinked[i])))
2518			return __this_address;
2519	}
2520
2521	return NULL;
2522}
2523
2524static void
2525xfs_agi_read_verify(
2526	struct xfs_buf	*bp)
2527{
2528	struct xfs_mount *mp = bp->b_mount;
2529	xfs_failaddr_t	fa;
2530
2531	if (xfs_sb_version_hascrc(&mp->m_sb) &&
2532	    !xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
2533		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
2534	else {
2535		fa = xfs_agi_verify(bp);
2536		if (XFS_TEST_ERROR(fa, mp, XFS_ERRTAG_IALLOC_READ_AGI))
2537			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2538	}
2539}
2540
2541static void
2542xfs_agi_write_verify(
2543	struct xfs_buf	*bp)
2544{
2545	struct xfs_mount	*mp = bp->b_mount;
2546	struct xfs_buf_log_item	*bip = bp->b_log_item;
2547	struct xfs_agi		*agi = bp->b_addr;
2548	xfs_failaddr_t		fa;
2549
2550	fa = xfs_agi_verify(bp);
2551	if (fa) {
2552		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2553		return;
2554	}
2555
2556	if (!xfs_sb_version_hascrc(&mp->m_sb))
2557		return;
2558
2559	if (bip)
2560		agi->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2561	xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
2562}
2563
2564const struct xfs_buf_ops xfs_agi_buf_ops = {
2565	.name = "xfs_agi",
2566	.magic = { cpu_to_be32(XFS_AGI_MAGIC), cpu_to_be32(XFS_AGI_MAGIC) },
2567	.verify_read = xfs_agi_read_verify,
2568	.verify_write = xfs_agi_write_verify,
2569	.verify_struct = xfs_agi_verify,
2570};
2571
2572/*
2573 * Read in the allocation group header (inode allocation section)
2574 */
2575int
2576xfs_read_agi(
2577	struct xfs_mount	*mp,	/* file system mount structure */
2578	struct xfs_trans	*tp,	/* transaction pointer */
2579	xfs_agnumber_t		agno,	/* allocation group number */
2580	struct xfs_buf		**bpp)	/* allocation group hdr buf */
2581{
 
2582	int			error;
2583
2584	trace_xfs_read_agi(mp, agno);
2585
2586	ASSERT(agno != NULLAGNUMBER);
2587	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
2588			XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
2589			XFS_FSS_TO_BB(mp, 1), 0, bpp, &xfs_agi_buf_ops);
2590	if (error)
2591		return error;
2592	if (tp)
2593		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_AGI_BUF);
2594
2595	xfs_buf_set_ref(*bpp, XFS_AGI_REF);
2596	return 0;
2597}
2598
 
 
 
 
2599int
2600xfs_ialloc_read_agi(
2601	struct xfs_mount	*mp,	/* file system mount structure */
2602	struct xfs_trans	*tp,	/* transaction pointer */
2603	xfs_agnumber_t		agno,	/* allocation group number */
2604	struct xfs_buf		**bpp)	/* allocation group hdr buf */
2605{
2606	struct xfs_agi		*agi;	/* allocation group header */
2607	struct xfs_perag	*pag;	/* per allocation group data */
2608	int			error;
2609
2610	trace_xfs_ialloc_read_agi(mp, agno);
2611
2612	error = xfs_read_agi(mp, tp, agno, bpp);
2613	if (error)
2614		return error;
2615
2616	agi = (*bpp)->b_addr;
2617	pag = (*bpp)->b_pag;
2618	if (!pag->pagi_init) {
2619		pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
2620		pag->pagi_count = be32_to_cpu(agi->agi_count);
2621		pag->pagi_init = 1;
2622	}
2623
2624	/*
2625	 * It's possible for these to be out of sync if
2626	 * we are in the middle of a forced shutdown.
2627	 */
2628	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
2629		XFS_FORCED_SHUTDOWN(mp));
 
 
 
 
2630	return 0;
2631}
2632
2633/*
2634 * Read in the agi to initialise the per-ag data in the mount structure
2635 */
2636int
2637xfs_ialloc_pagi_init(
2638	xfs_mount_t	*mp,		/* file system mount structure */
2639	xfs_trans_t	*tp,		/* transaction pointer */
2640	xfs_agnumber_t	agno)		/* allocation group number */
2641{
2642	struct xfs_buf	*bp = NULL;
2643	int		error;
 
 
2644
2645	error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
2646	if (error)
2647		return error;
2648	if (bp)
2649		xfs_trans_brelse(tp, bp);
2650	return 0;
2651}
2652
2653/* Is there an inode record covering a given range of inode numbers? */
2654int
2655xfs_ialloc_has_inode_record(
2656	struct xfs_btree_cur	*cur,
2657	xfs_agino_t		low,
2658	xfs_agino_t		high,
2659	bool			*exists)
2660{
2661	struct xfs_inobt_rec_incore	irec;
2662	xfs_agino_t		agino;
2663	uint16_t		holemask;
2664	int			has_record;
2665	int			i;
2666	int			error;
2667
2668	*exists = false;
2669	error = xfs_inobt_lookup(cur, low, XFS_LOOKUP_LE, &has_record);
2670	while (error == 0 && has_record) {
2671		error = xfs_inobt_get_rec(cur, &irec, &has_record);
2672		if (error || irec.ir_startino > high)
 
 
2673			break;
2674
2675		agino = irec.ir_startino;
2676		holemask = irec.ir_holemask;
2677		for (i = 0; i < XFS_INOBT_HOLEMASK_BITS; holemask >>= 1,
2678				i++, agino += XFS_INODES_PER_HOLEMASK_BIT) {
2679			if (holemask & 1)
2680				continue;
2681			if (agino + XFS_INODES_PER_HOLEMASK_BIT > low &&
2682					agino <= high) {
2683				*exists = true;
2684				return 0;
2685			}
 
2686		}
2687
2688		error = xfs_btree_increment(cur, 0, &has_record);
 
 
2689	}
2690	return error;
 
 
2691}
2692
2693/* Is there an inode record covering a given extent? */
2694int
2695xfs_ialloc_has_inodes_at_extent(
2696	struct xfs_btree_cur	*cur,
2697	xfs_agblock_t		bno,
2698	xfs_extlen_t		len,
2699	bool			*exists)
2700{
2701	xfs_agino_t		low;
2702	xfs_agino_t		high;
 
 
2703
2704	low = XFS_AGB_TO_AGINO(cur->bc_mp, bno);
2705	high = XFS_AGB_TO_AGINO(cur->bc_mp, bno + len) - 1;
2706
2707	return xfs_ialloc_has_inode_record(cur, low, high, exists);
 
 
 
 
 
 
 
 
 
 
2708}
2709
2710struct xfs_ialloc_count_inodes {
2711	xfs_agino_t			count;
2712	xfs_agino_t			freecount;
2713};
2714
2715/* Record inode counts across all inobt records. */
2716STATIC int
2717xfs_ialloc_count_inodes_rec(
2718	struct xfs_btree_cur		*cur,
2719	union xfs_btree_rec		*rec,
2720	void				*priv)
2721{
2722	struct xfs_inobt_rec_incore	irec;
2723	struct xfs_ialloc_count_inodes	*ci = priv;
 
2724
2725	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
 
 
 
 
2726	ci->count += irec.ir_count;
2727	ci->freecount += irec.ir_freecount;
2728
2729	return 0;
2730}
2731
2732/* Count allocated and free inodes under an inobt. */
2733int
2734xfs_ialloc_count_inodes(
2735	struct xfs_btree_cur		*cur,
2736	xfs_agino_t			*count,
2737	xfs_agino_t			*freecount)
2738{
2739	struct xfs_ialloc_count_inodes	ci = {0};
2740	int				error;
2741
2742	ASSERT(cur->bc_btnum == XFS_BTNUM_INO);
2743	error = xfs_btree_query_all(cur, xfs_ialloc_count_inodes_rec, &ci);
2744	if (error)
2745		return error;
2746
2747	*count = ci.count;
2748	*freecount = ci.freecount;
2749	return 0;
2750}
2751
2752/*
2753 * Initialize inode-related geometry information.
2754 *
2755 * Compute the inode btree min and max levels and set maxicount.
2756 *
2757 * Set the inode cluster size.  This may still be overridden by the file
2758 * system block size if it is larger than the chosen cluster size.
2759 *
2760 * For v5 filesystems, scale the cluster size with the inode size to keep a
2761 * constant ratio of inode per cluster buffer, but only if mkfs has set the
2762 * inode alignment value appropriately for larger cluster sizes.
2763 *
2764 * Then compute the inode cluster alignment information.
2765 */
2766void
2767xfs_ialloc_setup_geometry(
2768	struct xfs_mount	*mp)
2769{
2770	struct xfs_sb		*sbp = &mp->m_sb;
2771	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2772	uint64_t		icount;
2773	uint			inodes;
2774
2775	igeo->new_diflags2 = 0;
2776	if (xfs_sb_version_hasbigtime(&mp->m_sb))
2777		igeo->new_diflags2 |= XFS_DIFLAG2_BIGTIME;
 
 
2778
2779	/* Compute inode btree geometry. */
2780	igeo->agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
2781	igeo->inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
2782	igeo->inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
2783	igeo->inobt_mnr[0] = igeo->inobt_mxr[0] / 2;
2784	igeo->inobt_mnr[1] = igeo->inobt_mxr[1] / 2;
2785
2786	igeo->ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK,
2787			sbp->sb_inopblock);
2788	igeo->ialloc_blks = igeo->ialloc_inos >> sbp->sb_inopblog;
2789
2790	if (sbp->sb_spino_align)
2791		igeo->ialloc_min_blks = sbp->sb_spino_align;
2792	else
2793		igeo->ialloc_min_blks = igeo->ialloc_blks;
2794
2795	/* Compute and fill in value of m_ino_geo.inobt_maxlevels. */
2796	inodes = (1LL << XFS_INO_AGINO_BITS(mp)) >> XFS_INODES_PER_CHUNK_LOG;
2797	igeo->inobt_maxlevels = xfs_btree_compute_maxlevels(igeo->inobt_mnr,
2798			inodes);
 
2799
2800	/*
2801	 * Set the maximum inode count for this filesystem, being careful not
2802	 * to use obviously garbage sb_inopblog/sb_inopblock values.  Regular
2803	 * users should never get here due to failing sb verification, but
2804	 * certain users (xfs_db) need to be usable even with corrupt metadata.
2805	 */
2806	if (sbp->sb_imax_pct && igeo->ialloc_blks) {
2807		/*
2808		 * Make sure the maximum inode count is a multiple
2809		 * of the units we allocate inodes in.
2810		 */
2811		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
2812		do_div(icount, 100);
2813		do_div(icount, igeo->ialloc_blks);
2814		igeo->maxicount = XFS_FSB_TO_INO(mp,
2815				icount * igeo->ialloc_blks);
2816	} else {
2817		igeo->maxicount = 0;
2818	}
2819
2820	/*
2821	 * Compute the desired size of an inode cluster buffer size, which
2822	 * starts at 8K and (on v5 filesystems) scales up with larger inode
2823	 * sizes.
2824	 *
2825	 * Preserve the desired inode cluster size because the sparse inodes
2826	 * feature uses that desired size (not the actual size) to compute the
2827	 * sparse inode alignment.  The mount code validates this value, so we
2828	 * cannot change the behavior.
2829	 */
2830	igeo->inode_cluster_size_raw = XFS_INODE_BIG_CLUSTER_SIZE;
2831	if (xfs_sb_version_has_v3inode(&mp->m_sb)) {
2832		int	new_size = igeo->inode_cluster_size_raw;
2833
2834		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
2835		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
2836			igeo->inode_cluster_size_raw = new_size;
2837	}
2838
2839	/* Calculate inode cluster ratios. */
2840	if (igeo->inode_cluster_size_raw > mp->m_sb.sb_blocksize)
2841		igeo->blocks_per_cluster = XFS_B_TO_FSBT(mp,
2842				igeo->inode_cluster_size_raw);
2843	else
2844		igeo->blocks_per_cluster = 1;
2845	igeo->inode_cluster_size = XFS_FSB_TO_B(mp, igeo->blocks_per_cluster);
2846	igeo->inodes_per_cluster = XFS_FSB_TO_INO(mp, igeo->blocks_per_cluster);
2847
2848	/* Calculate inode cluster alignment. */
2849	if (xfs_sb_version_hasalign(&mp->m_sb) &&
2850	    mp->m_sb.sb_inoalignmt >= igeo->blocks_per_cluster)
2851		igeo->cluster_align = mp->m_sb.sb_inoalignmt;
2852	else
2853		igeo->cluster_align = 1;
2854	igeo->inoalign_mask = igeo->cluster_align - 1;
2855	igeo->cluster_align_inodes = XFS_FSB_TO_INO(mp, igeo->cluster_align);
2856
2857	/*
2858	 * If we are using stripe alignment, check whether
2859	 * the stripe unit is a multiple of the inode alignment
2860	 */
2861	if (mp->m_dalign && igeo->inoalign_mask &&
2862	    !(mp->m_dalign & igeo->inoalign_mask))
2863		igeo->ialloc_align = mp->m_dalign;
2864	else
2865		igeo->ialloc_align = 0;
2866}
2867
2868/* Compute the location of the root directory inode that is laid out by mkfs. */
2869xfs_ino_t
2870xfs_ialloc_calc_rootino(
2871	struct xfs_mount	*mp,
2872	int			sunit)
2873{
2874	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2875	xfs_agblock_t		first_bno;
2876
2877	/*
2878	 * Pre-calculate the geometry of AG 0.  We know what it looks like
2879	 * because libxfs knows how to create allocation groups now.
2880	 *
2881	 * first_bno is the first block in which mkfs could possibly have
2882	 * allocated the root directory inode, once we factor in the metadata
2883	 * that mkfs formats before it.  Namely, the four AG headers...
2884	 */
2885	first_bno = howmany(4 * mp->m_sb.sb_sectsize, mp->m_sb.sb_blocksize);
2886
2887	/* ...the two free space btree roots... */
2888	first_bno += 2;
2889
2890	/* ...the inode btree root... */
2891	first_bno += 1;
2892
2893	/* ...the initial AGFL... */
2894	first_bno += xfs_alloc_min_freelist(mp, NULL);
2895
2896	/* ...the free inode btree root... */
2897	if (xfs_sb_version_hasfinobt(&mp->m_sb))
2898		first_bno++;
2899
2900	/* ...the reverse mapping btree root... */
2901	if (xfs_sb_version_hasrmapbt(&mp->m_sb))
2902		first_bno++;
2903
2904	/* ...the reference count btree... */
2905	if (xfs_sb_version_hasreflink(&mp->m_sb))
2906		first_bno++;
2907
2908	/*
2909	 * ...and the log, if it is allocated in the first allocation group.
2910	 *
2911	 * This can happen with filesystems that only have a single
2912	 * allocation group, or very odd geometries created by old mkfs
2913	 * versions on very small filesystems.
2914	 */
2915	if (mp->m_sb.sb_logstart &&
2916	    XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart) == 0)
2917		 first_bno += mp->m_sb.sb_logblocks;
2918
2919	/*
2920	 * Now round first_bno up to whatever allocation alignment is given
2921	 * by the filesystem or was passed in.
2922	 */
2923	if (xfs_sb_version_hasdalign(&mp->m_sb) && igeo->ialloc_align > 0)
2924		first_bno = roundup(first_bno, sunit);
2925	else if (xfs_sb_version_hasalign(&mp->m_sb) &&
2926			mp->m_sb.sb_inoalignmt > 1)
2927		first_bno = roundup(first_bno, mp->m_sb.sb_inoalignmt);
2928
2929	return XFS_AGINO_TO_INO(mp, 0, XFS_AGB_TO_AGINO(mp, first_bno));
2930}
2931
2932/*
2933 * Ensure there are not sparse inode clusters that cross the new EOAG.
2934 *
2935 * This is a no-op for non-spinode filesystems since clusters are always fully
2936 * allocated and checking the bnobt suffices.  However, a spinode filesystem
2937 * could have a record where the upper inodes are free blocks.  If those blocks
2938 * were removed from the filesystem, the inode record would extend beyond EOAG,
2939 * which will be flagged as corruption.
2940 */
2941int
2942xfs_ialloc_check_shrink(
 
2943	struct xfs_trans	*tp,
2944	xfs_agnumber_t		agno,
2945	struct xfs_buf		*agibp,
2946	xfs_agblock_t		new_length)
2947{
2948	struct xfs_inobt_rec_incore rec;
2949	struct xfs_btree_cur	*cur;
2950	struct xfs_mount	*mp = tp->t_mountp;
2951	struct xfs_perag	*pag;
2952	xfs_agino_t		agino = XFS_AGB_TO_AGINO(mp, new_length);
2953	int			has;
2954	int			error;
2955
2956	if (!xfs_sb_version_hassparseinodes(&mp->m_sb))
2957		return 0;
2958
2959	pag = xfs_perag_get(mp, agno);
2960	cur = xfs_inobt_init_cursor(mp, tp, agibp, pag, XFS_BTNUM_INO);
2961
2962	/* Look up the inobt record that would correspond to the new EOFS. */
 
2963	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &has);
2964	if (error || !has)
2965		goto out;
2966
2967	error = xfs_inobt_get_rec(cur, &rec, &has);
2968	if (error)
2969		goto out;
2970
2971	if (!has) {
2972		error = -EFSCORRUPTED;
2973		goto out;
2974	}
2975
2976	/* If the record covers inodes that would be beyond EOFS, bail out. */
2977	if (rec.ir_startino + XFS_INODES_PER_CHUNK > agino) {
2978		error = -ENOSPC;
2979		goto out;
2980	}
2981out:
2982	xfs_btree_del_cursor(cur, error);
2983	xfs_perag_put(pag);
2984	return error;
2985}