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v6.2
   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/*
  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	union xfs_btree_rec		*rec;
 109	int				error;
 110	uint64_t			realfree;
 111
 112	error = xfs_btree_get_rec(cur, &rec, stat);
 113	if (error || *stat == 0)
 114		return error;
 115
 116	xfs_inobt_btrec_to_irec(mp, rec, irec);
 117
 118	if (!xfs_verify_agino(cur->bc_ag.pag, irec->ir_startino))
 119		goto out_bad_rec;
 120	if (irec->ir_count < XFS_INODES_PER_HOLEMASK_BIT ||
 121	    irec->ir_count > XFS_INODES_PER_CHUNK)
 122		goto out_bad_rec;
 123	if (irec->ir_freecount > XFS_INODES_PER_CHUNK)
 124		goto out_bad_rec;
 125
 126	/* if there are no holes, return the first available offset */
 127	if (!xfs_inobt_issparse(irec->ir_holemask))
 128		realfree = irec->ir_free;
 129	else
 130		realfree = irec->ir_free & xfs_inobt_irec_to_allocmask(irec);
 131	if (hweight64(realfree) != irec->ir_freecount)
 132		goto out_bad_rec;
 133
 134	return 0;
 135
 136out_bad_rec:
 137	xfs_warn(mp,
 138		"%s Inode BTree record corruption in AG %d detected!",
 139		cur->bc_btnum == XFS_BTNUM_INO ? "Used" : "Free",
 140		cur->bc_ag.pag->pag_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_is_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_has_v3inodes(mp)) {
 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
 341			free = xfs_make_iptr(mp, fbuf, i);
 342			free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
 343			free->di_version = version;
 344			free->di_gen = cpu_to_be32(gen);
 345			free->di_next_unlinked = cpu_to_be32(NULLAGINO);
 346
 347			if (version == 3) {
 348				free->di_ino = cpu_to_be64(ino);
 349				ino++;
 350				uuid_copy(&free->di_uuid,
 351					  &mp->m_sb.sb_meta_uuid);
 352				xfs_dinode_calc_crc(mp, free);
 353			} else if (tp) {
 354				/* just log the inode core */
 355				xfs_trans_log_buf(tp, fbuf, ioffset,
 356					  ioffset + XFS_DINODE_SIZE(mp) - 1);
 357			}
 358		}
 359
 360		if (tp) {
 361			/*
 362			 * Mark the buffer as an inode allocation buffer so it
 363			 * sticks in AIL at the point of this allocation
 364			 * transaction. This ensures the they are on disk before
 365			 * the tail of the log can be moved past this
 366			 * transaction (i.e. by preventing relogging from moving
 367			 * it forward in the log).
 368			 */
 369			xfs_trans_inode_alloc_buf(tp, fbuf);
 370			if (version == 3) {
 371				/*
 372				 * Mark the buffer as ordered so that they are
 373				 * not physically logged in the transaction but
 374				 * still tracked in the AIL as part of the
 375				 * transaction and pin the log appropriately.
 376				 */
 377				xfs_trans_ordered_buf(tp, fbuf);
 378			}
 379		} else {
 380			fbuf->b_flags |= XBF_DONE;
 381			xfs_buf_delwri_queue(fbuf, buffer_list);
 382			xfs_buf_relse(fbuf);
 383		}
 384	}
 385	return 0;
 386}
 387
 388/*
 389 * Align startino and allocmask for a recently allocated sparse chunk such that
 390 * they are fit for insertion (or merge) into the on-disk inode btrees.
 391 *
 392 * Background:
 393 *
 394 * When enabled, sparse inode support increases the inode alignment from cluster
 395 * size to inode chunk size. This means that the minimum range between two
 396 * non-adjacent inode records in the inobt is large enough for a full inode
 397 * record. This allows for cluster sized, cluster aligned block allocation
 398 * without need to worry about whether the resulting inode record overlaps with
 399 * another record in the tree. Without this basic rule, we would have to deal
 400 * with the consequences of overlap by potentially undoing recent allocations in
 401 * the inode allocation codepath.
 402 *
 403 * Because of this alignment rule (which is enforced on mount), there are two
 404 * inobt possibilities for newly allocated sparse chunks. One is that the
 405 * aligned inode record for the chunk covers a range of inodes not already
 406 * covered in the inobt (i.e., it is safe to insert a new sparse record). The
 407 * other is that a record already exists at the aligned startino that considers
 408 * the newly allocated range as sparse. In the latter case, record content is
 409 * merged in hope that sparse inode chunks fill to full chunks over time.
 410 */
 411STATIC void
 412xfs_align_sparse_ino(
 413	struct xfs_mount		*mp,
 414	xfs_agino_t			*startino,
 415	uint16_t			*allocmask)
 416{
 417	xfs_agblock_t			agbno;
 418	xfs_agblock_t			mod;
 419	int				offset;
 420
 421	agbno = XFS_AGINO_TO_AGBNO(mp, *startino);
 422	mod = agbno % mp->m_sb.sb_inoalignmt;
 423	if (!mod)
 424		return;
 425
 426	/* calculate the inode offset and align startino */
 427	offset = XFS_AGB_TO_AGINO(mp, mod);
 428	*startino -= offset;
 429
 430	/*
 431	 * Since startino has been aligned down, left shift allocmask such that
 432	 * it continues to represent the same physical inodes relative to the
 433	 * new startino.
 434	 */
 435	*allocmask <<= offset / XFS_INODES_PER_HOLEMASK_BIT;
 436}
 437
 438/*
 439 * Determine whether the source inode record can merge into the target. Both
 440 * records must be sparse, the inode ranges must match and there must be no
 441 * allocation overlap between the records.
 442 */
 443STATIC bool
 444__xfs_inobt_can_merge(
 445	struct xfs_inobt_rec_incore	*trec,	/* tgt record */
 446	struct xfs_inobt_rec_incore	*srec)	/* src record */
 447{
 448	uint64_t			talloc;
 449	uint64_t			salloc;
 450
 451	/* records must cover the same inode range */
 452	if (trec->ir_startino != srec->ir_startino)
 453		return false;
 454
 455	/* both records must be sparse */
 456	if (!xfs_inobt_issparse(trec->ir_holemask) ||
 457	    !xfs_inobt_issparse(srec->ir_holemask))
 458		return false;
 459
 460	/* both records must track some inodes */
 461	if (!trec->ir_count || !srec->ir_count)
 462		return false;
 463
 464	/* can't exceed capacity of a full record */
 465	if (trec->ir_count + srec->ir_count > XFS_INODES_PER_CHUNK)
 466		return false;
 467
 468	/* verify there is no allocation overlap */
 469	talloc = xfs_inobt_irec_to_allocmask(trec);
 470	salloc = xfs_inobt_irec_to_allocmask(srec);
 471	if (talloc & salloc)
 472		return false;
 473
 474	return true;
 475}
 476
 477/*
 478 * Merge the source inode record into the target. The caller must call
 479 * __xfs_inobt_can_merge() to ensure the merge is valid.
 480 */
 481STATIC void
 482__xfs_inobt_rec_merge(
 483	struct xfs_inobt_rec_incore	*trec,	/* target */
 484	struct xfs_inobt_rec_incore	*srec)	/* src */
 485{
 486	ASSERT(trec->ir_startino == srec->ir_startino);
 487
 488	/* combine the counts */
 489	trec->ir_count += srec->ir_count;
 490	trec->ir_freecount += srec->ir_freecount;
 491
 492	/*
 493	 * Merge the holemask and free mask. For both fields, 0 bits refer to
 494	 * allocated inodes. We combine the allocated ranges with bitwise AND.
 495	 */
 496	trec->ir_holemask &= srec->ir_holemask;
 497	trec->ir_free &= srec->ir_free;
 498}
 499
 500/*
 501 * Insert a new sparse inode chunk into the associated inode btree. The inode
 502 * record for the sparse chunk is pre-aligned to a startino that should match
 503 * any pre-existing sparse inode record in the tree. This allows sparse chunks
 504 * to fill over time.
 505 *
 506 * This function supports two modes of handling preexisting records depending on
 507 * the merge flag. If merge is true, the provided record is merged with the
 508 * existing record and updated in place. The merged record is returned in nrec.
 509 * If merge is false, an existing record is replaced with the provided record.
 510 * If no preexisting record exists, the provided record is always inserted.
 511 *
 512 * It is considered corruption if a merge is requested and not possible. Given
 513 * the sparse inode alignment constraints, this should never happen.
 514 */
 515STATIC int
 516xfs_inobt_insert_sprec(
 517	struct xfs_mount		*mp,
 518	struct xfs_trans		*tp,
 519	struct xfs_buf			*agbp,
 520	struct xfs_perag		*pag,
 521	int				btnum,
 522	struct xfs_inobt_rec_incore	*nrec,	/* in/out: new/merged rec. */
 523	bool				merge)	/* merge or replace */
 524{
 525	struct xfs_btree_cur		*cur;
 
 
 526	int				error;
 527	int				i;
 528	struct xfs_inobt_rec_incore	rec;
 529
 530	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, btnum);
 531
 532	/* the new record is pre-aligned so we know where to look */
 533	error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
 534	if (error)
 535		goto error;
 536	/* if nothing there, insert a new record and return */
 537	if (i == 0) {
 538		error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
 539					     nrec->ir_count, nrec->ir_freecount,
 540					     nrec->ir_free, &i);
 541		if (error)
 542			goto error;
 543		if (XFS_IS_CORRUPT(mp, i != 1)) {
 544			error = -EFSCORRUPTED;
 545			goto error;
 546		}
 547
 548		goto out;
 549	}
 550
 551	/*
 552	 * A record exists at this startino. Merge or replace the record
 553	 * depending on what we've been asked to do.
 554	 */
 555	if (merge) {
 556		error = xfs_inobt_get_rec(cur, &rec, &i);
 557		if (error)
 558			goto error;
 559		if (XFS_IS_CORRUPT(mp, i != 1)) {
 560			error = -EFSCORRUPTED;
 561			goto error;
 562		}
 563		if (XFS_IS_CORRUPT(mp, rec.ir_startino != nrec->ir_startino)) {
 564			error = -EFSCORRUPTED;
 565			goto error;
 566		}
 567
 568		/*
 569		 * This should never fail. If we have coexisting records that
 570		 * cannot merge, something is seriously wrong.
 571		 */
 572		if (XFS_IS_CORRUPT(mp, !__xfs_inobt_can_merge(nrec, &rec))) {
 573			error = -EFSCORRUPTED;
 574			goto error;
 575		}
 576
 577		trace_xfs_irec_merge_pre(mp, pag->pag_agno, rec.ir_startino,
 578					 rec.ir_holemask, nrec->ir_startino,
 579					 nrec->ir_holemask);
 580
 581		/* merge to nrec to output the updated record */
 582		__xfs_inobt_rec_merge(nrec, &rec);
 583
 584		trace_xfs_irec_merge_post(mp, pag->pag_agno, nrec->ir_startino,
 585					  nrec->ir_holemask);
 586
 587		error = xfs_inobt_rec_check_count(mp, nrec);
 588		if (error)
 589			goto error;
 590	}
 591
 592	error = xfs_inobt_update(cur, nrec);
 593	if (error)
 594		goto error;
 595
 596out:
 597	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 598	return 0;
 599error:
 600	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 601	return error;
 602}
 603
 604/*
 605 * Allocate new inodes in the allocation group specified by agbp.  Returns 0 if
 606 * inodes were allocated in this AG; -EAGAIN if there was no space in this AG so
 607 * the caller knows it can try another AG, a hard -ENOSPC when over the maximum
 608 * inode count threshold, or the usual negative error code for other errors.
 609 */
 610STATIC int
 611xfs_ialloc_ag_alloc(
 612	struct xfs_trans	*tp,
 613	struct xfs_buf		*agbp,
 614	struct xfs_perag	*pag)
 615{
 616	struct xfs_agi		*agi;
 617	struct xfs_alloc_arg	args;
 
 618	int			error;
 619	xfs_agino_t		newino;		/* new first inode's number */
 620	xfs_agino_t		newlen;		/* new number of inodes */
 621	int			isaligned = 0;	/* inode allocation at stripe */
 622						/* unit boundary */
 623	/* init. to full chunk */
 
 624	struct xfs_inobt_rec_incore rec;
 
 625	struct xfs_ino_geometry	*igeo = M_IGEO(tp->t_mountp);
 626	uint16_t		allocmask = (uint16_t) -1;
 627	int			do_sparse = 0;
 628
 629	memset(&args, 0, sizeof(args));
 630	args.tp = tp;
 631	args.mp = tp->t_mountp;
 632	args.fsbno = NULLFSBLOCK;
 633	args.oinfo = XFS_RMAP_OINFO_INODES;
 634
 635#ifdef DEBUG
 636	/* randomly do sparse inode allocations */
 637	if (xfs_has_sparseinodes(tp->t_mountp) &&
 638	    igeo->ialloc_min_blks < igeo->ialloc_blks)
 639		do_sparse = get_random_u32_below(2);
 640#endif
 641
 642	/*
 643	 * Locking will ensure that we don't have two callers in here
 644	 * at one time.
 645	 */
 646	newlen = igeo->ialloc_inos;
 647	if (igeo->maxicount &&
 648	    percpu_counter_read_positive(&args.mp->m_icount) + newlen >
 649							igeo->maxicount)
 650		return -ENOSPC;
 651	args.minlen = args.maxlen = igeo->ialloc_blks;
 652	/*
 653	 * First try to allocate inodes contiguous with the last-allocated
 654	 * chunk of inodes.  If the filesystem is striped, this will fill
 655	 * an entire stripe unit with inodes.
 656	 */
 657	agi = agbp->b_addr;
 658	newino = be32_to_cpu(agi->agi_newino);
 
 659	args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
 660		     igeo->ialloc_blks;
 661	if (do_sparse)
 662		goto sparse_alloc;
 663	if (likely(newino != NULLAGINO &&
 664		  (args.agbno < be32_to_cpu(agi->agi_length)))) {
 665		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 666		args.type = XFS_ALLOCTYPE_THIS_BNO;
 667		args.prod = 1;
 668
 669		/*
 670		 * We need to take into account alignment here to ensure that
 671		 * we don't modify the free list if we fail to have an exact
 672		 * block. If we don't have an exact match, and every oher
 673		 * attempt allocation attempt fails, we'll end up cancelling
 674		 * a dirty transaction and shutting down.
 675		 *
 676		 * For an exact allocation, alignment must be 1,
 677		 * however we need to take cluster alignment into account when
 678		 * fixing up the freelist. Use the minalignslop field to
 679		 * indicate that extra blocks might be required for alignment,
 680		 * but not to use them in the actual exact allocation.
 681		 */
 682		args.alignment = 1;
 683		args.minalignslop = igeo->cluster_align - 1;
 684
 685		/* Allow space for the inode btree to split. */
 686		args.minleft = igeo->inobt_maxlevels;
 687		if ((error = xfs_alloc_vextent(&args)))
 688			return error;
 689
 690		/*
 691		 * This request might have dirtied the transaction if the AG can
 692		 * satisfy the request, but the exact block was not available.
 693		 * If the allocation did fail, subsequent requests will relax
 694		 * the exact agbno requirement and increase the alignment
 695		 * instead. It is critical that the total size of the request
 696		 * (len + alignment + slop) does not increase from this point
 697		 * on, so reset minalignslop to ensure it is not included in
 698		 * subsequent requests.
 699		 */
 700		args.minalignslop = 0;
 701	}
 702
 703	if (unlikely(args.fsbno == NULLFSBLOCK)) {
 704		/*
 705		 * Set the alignment for the allocation.
 706		 * If stripe alignment is turned on then align at stripe unit
 707		 * boundary.
 708		 * If the cluster size is smaller than a filesystem block
 709		 * then we're doing I/O for inodes in filesystem block size
 710		 * pieces, so don't need alignment anyway.
 711		 */
 712		isaligned = 0;
 713		if (igeo->ialloc_align) {
 714			ASSERT(!xfs_has_noalign(args.mp));
 715			args.alignment = args.mp->m_dalign;
 716			isaligned = 1;
 717		} else
 718			args.alignment = igeo->cluster_align;
 719		/*
 720		 * Need to figure out where to allocate the inode blocks.
 721		 * Ideally they should be spaced out through the a.g.
 722		 * For now, just allocate blocks up front.
 723		 */
 724		args.agbno = be32_to_cpu(agi->agi_root);
 725		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 726		/*
 727		 * Allocate a fixed-size extent of inodes.
 728		 */
 729		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 730		args.prod = 1;
 731		/*
 732		 * Allow space for the inode btree to split.
 733		 */
 734		args.minleft = igeo->inobt_maxlevels;
 735		if ((error = xfs_alloc_vextent(&args)))
 736			return error;
 737	}
 738
 739	/*
 740	 * If stripe alignment is turned on, then try again with cluster
 741	 * alignment.
 742	 */
 743	if (isaligned && args.fsbno == NULLFSBLOCK) {
 744		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 745		args.agbno = be32_to_cpu(agi->agi_root);
 746		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 747		args.alignment = igeo->cluster_align;
 748		if ((error = xfs_alloc_vextent(&args)))
 749			return error;
 750	}
 751
 752	/*
 753	 * Finally, try a sparse allocation if the filesystem supports it and
 754	 * the sparse allocation length is smaller than a full chunk.
 755	 */
 756	if (xfs_has_sparseinodes(args.mp) &&
 757	    igeo->ialloc_min_blks < igeo->ialloc_blks &&
 758	    args.fsbno == NULLFSBLOCK) {
 759sparse_alloc:
 760		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 761		args.agbno = be32_to_cpu(agi->agi_root);
 762		args.fsbno = XFS_AGB_TO_FSB(args.mp, pag->pag_agno, args.agbno);
 763		args.alignment = args.mp->m_sb.sb_spino_align;
 764		args.prod = 1;
 765
 766		args.minlen = igeo->ialloc_min_blks;
 767		args.maxlen = args.minlen;
 768
 769		/*
 770		 * The inode record will be aligned to full chunk size. We must
 771		 * prevent sparse allocation from AG boundaries that result in
 772		 * invalid inode records, such as records that start at agbno 0
 773		 * or extend beyond the AG.
 774		 *
 775		 * Set min agbno to the first aligned, non-zero agbno and max to
 776		 * the last aligned agbno that is at least one full chunk from
 777		 * the end of the AG.
 778		 */
 779		args.min_agbno = args.mp->m_sb.sb_inoalignmt;
 780		args.max_agbno = round_down(args.mp->m_sb.sb_agblocks,
 781					    args.mp->m_sb.sb_inoalignmt) -
 782				 igeo->ialloc_blks;
 783
 784		error = xfs_alloc_vextent(&args);
 785		if (error)
 786			return error;
 787
 788		newlen = XFS_AGB_TO_AGINO(args.mp, args.len);
 789		ASSERT(newlen <= XFS_INODES_PER_CHUNK);
 790		allocmask = (1 << (newlen / XFS_INODES_PER_HOLEMASK_BIT)) - 1;
 791	}
 792
 793	if (args.fsbno == NULLFSBLOCK)
 794		return -EAGAIN;
 795
 
 796	ASSERT(args.len == args.minlen);
 797
 798	/*
 799	 * Stamp and write the inode buffers.
 800	 *
 801	 * Seed the new inode cluster with a random generation number. This
 802	 * prevents short-term reuse of generation numbers if a chunk is
 803	 * freed and then immediately reallocated. We use random numbers
 804	 * rather than a linear progression to prevent the next generation
 805	 * number from being easily guessable.
 806	 */
 807	error = xfs_ialloc_inode_init(args.mp, tp, NULL, newlen, pag->pag_agno,
 808			args.agbno, args.len, get_random_u32());
 809
 810	if (error)
 811		return error;
 812	/*
 813	 * Convert the results.
 814	 */
 815	newino = XFS_AGB_TO_AGINO(args.mp, args.agbno);
 816
 817	if (xfs_inobt_issparse(~allocmask)) {
 818		/*
 819		 * We've allocated a sparse chunk. Align the startino and mask.
 820		 */
 821		xfs_align_sparse_ino(args.mp, &newino, &allocmask);
 822
 823		rec.ir_startino = newino;
 824		rec.ir_holemask = ~allocmask;
 825		rec.ir_count = newlen;
 826		rec.ir_freecount = newlen;
 827		rec.ir_free = XFS_INOBT_ALL_FREE;
 828
 829		/*
 830		 * Insert the sparse record into the inobt and allow for a merge
 831		 * if necessary. If a merge does occur, rec is updated to the
 832		 * merged record.
 833		 */
 834		error = xfs_inobt_insert_sprec(args.mp, tp, agbp, pag,
 835				XFS_BTNUM_INO, &rec, true);
 836		if (error == -EFSCORRUPTED) {
 837			xfs_alert(args.mp,
 838	"invalid sparse inode record: ino 0x%llx holemask 0x%x count %u",
 839				  XFS_AGINO_TO_INO(args.mp, pag->pag_agno,
 840						   rec.ir_startino),
 841				  rec.ir_holemask, rec.ir_count);
 842			xfs_force_shutdown(args.mp, SHUTDOWN_CORRUPT_INCORE);
 843		}
 844		if (error)
 845			return error;
 846
 847		/*
 848		 * We can't merge the part we've just allocated as for the inobt
 849		 * due to finobt semantics. The original record may or may not
 850		 * exist independent of whether physical inodes exist in this
 851		 * sparse chunk.
 852		 *
 853		 * We must update the finobt record based on the inobt record.
 854		 * rec contains the fully merged and up to date inobt record
 855		 * from the previous call. Set merge false to replace any
 856		 * existing record with this one.
 857		 */
 858		if (xfs_has_finobt(args.mp)) {
 859			error = xfs_inobt_insert_sprec(args.mp, tp, agbp, pag,
 860				       XFS_BTNUM_FINO, &rec, false);
 
 861			if (error)
 862				return error;
 863		}
 864	} else {
 865		/* full chunk - insert new records to both btrees */
 866		error = xfs_inobt_insert(args.mp, tp, agbp, pag, newino, newlen,
 867					 XFS_BTNUM_INO);
 868		if (error)
 869			return error;
 870
 871		if (xfs_has_finobt(args.mp)) {
 872			error = xfs_inobt_insert(args.mp, tp, agbp, pag, newino,
 873						 newlen, XFS_BTNUM_FINO);
 874			if (error)
 875				return error;
 876		}
 877	}
 878
 879	/*
 880	 * Update AGI counts and newino.
 881	 */
 882	be32_add_cpu(&agi->agi_count, newlen);
 883	be32_add_cpu(&agi->agi_freecount, newlen);
 
 884	pag->pagi_freecount += newlen;
 885	pag->pagi_count += newlen;
 886	agi->agi_newino = cpu_to_be32(newino);
 887
 888	/*
 889	 * Log allocation group header fields
 890	 */
 891	xfs_ialloc_log_agi(tp, agbp,
 892		XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
 893	/*
 894	 * Modify/log superblock values for inode count and inode free count.
 895	 */
 896	xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
 897	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
 
 898	return 0;
 899}
 900
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 901/*
 902 * Try to retrieve the next record to the left/right from the current one.
 903 */
 904STATIC int
 905xfs_ialloc_next_rec(
 906	struct xfs_btree_cur	*cur,
 907	xfs_inobt_rec_incore_t	*rec,
 908	int			*done,
 909	int			left)
 910{
 911	int                     error;
 912	int			i;
 913
 914	if (left)
 915		error = xfs_btree_decrement(cur, 0, &i);
 916	else
 917		error = xfs_btree_increment(cur, 0, &i);
 918
 919	if (error)
 920		return error;
 921	*done = !i;
 922	if (i) {
 923		error = xfs_inobt_get_rec(cur, rec, &i);
 924		if (error)
 925			return error;
 926		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 927			return -EFSCORRUPTED;
 928	}
 929
 930	return 0;
 931}
 932
 933STATIC int
 934xfs_ialloc_get_rec(
 935	struct xfs_btree_cur	*cur,
 936	xfs_agino_t		agino,
 937	xfs_inobt_rec_incore_t	*rec,
 938	int			*done)
 939{
 940	int                     error;
 941	int			i;
 942
 943	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
 944	if (error)
 945		return error;
 946	*done = !i;
 947	if (i) {
 948		error = xfs_inobt_get_rec(cur, rec, &i);
 949		if (error)
 950			return error;
 951		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
 952			return -EFSCORRUPTED;
 953	}
 954
 955	return 0;
 956}
 957
 958/*
 959 * Return the offset of the first free inode in the record. If the inode chunk
 960 * is sparsely allocated, we convert the record holemask to inode granularity
 961 * and mask off the unallocated regions from the inode free mask.
 962 */
 963STATIC int
 964xfs_inobt_first_free_inode(
 965	struct xfs_inobt_rec_incore	*rec)
 966{
 967	xfs_inofree_t			realfree;
 968
 969	/* if there are no holes, return the first available offset */
 970	if (!xfs_inobt_issparse(rec->ir_holemask))
 971		return xfs_lowbit64(rec->ir_free);
 972
 973	realfree = xfs_inobt_irec_to_allocmask(rec);
 974	realfree &= rec->ir_free;
 975
 976	return xfs_lowbit64(realfree);
 977}
 978
 979/*
 980 * Allocate an inode using the inobt-only algorithm.
 981 */
 982STATIC int
 983xfs_dialloc_ag_inobt(
 984	struct xfs_trans	*tp,
 985	struct xfs_buf		*agbp,
 986	struct xfs_perag	*pag,
 987	xfs_ino_t		parent,
 988	xfs_ino_t		*inop)
 989{
 990	struct xfs_mount	*mp = tp->t_mountp;
 991	struct xfs_agi		*agi = agbp->b_addr;
 
 992	xfs_agnumber_t		pagno = XFS_INO_TO_AGNO(mp, parent);
 993	xfs_agino_t		pagino = XFS_INO_TO_AGINO(mp, parent);
 
 994	struct xfs_btree_cur	*cur, *tcur;
 995	struct xfs_inobt_rec_incore rec, trec;
 996	xfs_ino_t		ino;
 997	int			error;
 998	int			offset;
 999	int			i, j;
1000	int			searchdistance = 10;
1001
1002	ASSERT(pag->pagi_init);
1003	ASSERT(pag->pagi_inodeok);
1004	ASSERT(pag->pagi_freecount > 0);
1005
1006 restart_pagno:
1007	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1008	/*
1009	 * If pagino is 0 (this is the root inode allocation) use newino.
1010	 * This must work because we've just allocated some.
1011	 */
1012	if (!pagino)
1013		pagino = be32_to_cpu(agi->agi_newino);
1014
1015	error = xfs_check_agi_freecount(cur);
1016	if (error)
1017		goto error0;
1018
1019	/*
1020	 * If in the same AG as the parent, try to get near the parent.
1021	 */
1022	if (pagno == pag->pag_agno) {
1023		int		doneleft;	/* done, to the left */
1024		int		doneright;	/* done, to the right */
1025
1026		error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
1027		if (error)
1028			goto error0;
1029		if (XFS_IS_CORRUPT(mp, i != 1)) {
1030			error = -EFSCORRUPTED;
1031			goto error0;
1032		}
1033
1034		error = xfs_inobt_get_rec(cur, &rec, &j);
1035		if (error)
1036			goto error0;
1037		if (XFS_IS_CORRUPT(mp, j != 1)) {
1038			error = -EFSCORRUPTED;
1039			goto error0;
1040		}
1041
1042		if (rec.ir_freecount > 0) {
1043			/*
1044			 * Found a free inode in the same chunk
1045			 * as the parent, done.
1046			 */
1047			goto alloc_inode;
1048		}
1049
1050
1051		/*
1052		 * In the same AG as parent, but parent's chunk is full.
1053		 */
1054
1055		/* duplicate the cursor, search left & right simultaneously */
1056		error = xfs_btree_dup_cursor(cur, &tcur);
1057		if (error)
1058			goto error0;
1059
1060		/*
1061		 * Skip to last blocks looked up if same parent inode.
1062		 */
1063		if (pagino != NULLAGINO &&
1064		    pag->pagl_pagino == pagino &&
1065		    pag->pagl_leftrec != NULLAGINO &&
1066		    pag->pagl_rightrec != NULLAGINO) {
1067			error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
1068						   &trec, &doneleft);
1069			if (error)
1070				goto error1;
1071
1072			error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
1073						   &rec, &doneright);
1074			if (error)
1075				goto error1;
1076		} else {
1077			/* search left with tcur, back up 1 record */
1078			error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
1079			if (error)
1080				goto error1;
1081
1082			/* search right with cur, go forward 1 record. */
1083			error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
1084			if (error)
1085				goto error1;
1086		}
1087
1088		/*
1089		 * Loop until we find an inode chunk with a free inode.
1090		 */
1091		while (--searchdistance > 0 && (!doneleft || !doneright)) {
1092			int	useleft;  /* using left inode chunk this time */
1093
1094			/* figure out the closer block if both are valid. */
1095			if (!doneleft && !doneright) {
1096				useleft = pagino -
1097				 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
1098				  rec.ir_startino - pagino;
1099			} else {
1100				useleft = !doneleft;
1101			}
1102
1103			/* free inodes to the left? */
1104			if (useleft && trec.ir_freecount) {
1105				xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1106				cur = tcur;
1107
1108				pag->pagl_leftrec = trec.ir_startino;
1109				pag->pagl_rightrec = rec.ir_startino;
1110				pag->pagl_pagino = pagino;
1111				rec = trec;
1112				goto alloc_inode;
1113			}
1114
1115			/* free inodes to the right? */
1116			if (!useleft && rec.ir_freecount) {
1117				xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1118
1119				pag->pagl_leftrec = trec.ir_startino;
1120				pag->pagl_rightrec = rec.ir_startino;
1121				pag->pagl_pagino = pagino;
1122				goto alloc_inode;
1123			}
1124
1125			/* get next record to check */
1126			if (useleft) {
1127				error = xfs_ialloc_next_rec(tcur, &trec,
1128								 &doneleft, 1);
1129			} else {
1130				error = xfs_ialloc_next_rec(cur, &rec,
1131								 &doneright, 0);
1132			}
1133			if (error)
1134				goto error1;
1135		}
1136
1137		if (searchdistance <= 0) {
1138			/*
1139			 * Not in range - save last search
1140			 * location and allocate a new inode
1141			 */
1142			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1143			pag->pagl_leftrec = trec.ir_startino;
1144			pag->pagl_rightrec = rec.ir_startino;
1145			pag->pagl_pagino = pagino;
1146
1147		} else {
1148			/*
1149			 * We've reached the end of the btree. because
1150			 * we are only searching a small chunk of the
1151			 * btree each search, there is obviously free
1152			 * inodes closer to the parent inode than we
1153			 * are now. restart the search again.
1154			 */
1155			pag->pagl_pagino = NULLAGINO;
1156			pag->pagl_leftrec = NULLAGINO;
1157			pag->pagl_rightrec = NULLAGINO;
1158			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1159			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1160			goto restart_pagno;
1161		}
1162	}
1163
1164	/*
1165	 * In a different AG from the parent.
1166	 * See if the most recently allocated block has any free.
1167	 */
1168	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1169		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1170					 XFS_LOOKUP_EQ, &i);
1171		if (error)
1172			goto error0;
1173
1174		if (i == 1) {
1175			error = xfs_inobt_get_rec(cur, &rec, &j);
1176			if (error)
1177				goto error0;
1178
1179			if (j == 1 && rec.ir_freecount > 0) {
1180				/*
1181				 * The last chunk allocated in the group
1182				 * still has a free inode.
1183				 */
1184				goto alloc_inode;
1185			}
1186		}
1187	}
1188
1189	/*
1190	 * None left in the last group, search the whole AG
1191	 */
1192	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1193	if (error)
1194		goto error0;
1195	if (XFS_IS_CORRUPT(mp, i != 1)) {
1196		error = -EFSCORRUPTED;
1197		goto error0;
1198	}
1199
1200	for (;;) {
1201		error = xfs_inobt_get_rec(cur, &rec, &i);
1202		if (error)
1203			goto error0;
1204		if (XFS_IS_CORRUPT(mp, i != 1)) {
1205			error = -EFSCORRUPTED;
1206			goto error0;
1207		}
1208		if (rec.ir_freecount > 0)
1209			break;
1210		error = xfs_btree_increment(cur, 0, &i);
1211		if (error)
1212			goto error0;
1213		if (XFS_IS_CORRUPT(mp, i != 1)) {
1214			error = -EFSCORRUPTED;
1215			goto error0;
1216		}
1217	}
1218
1219alloc_inode:
1220	offset = xfs_inobt_first_free_inode(&rec);
1221	ASSERT(offset >= 0);
1222	ASSERT(offset < XFS_INODES_PER_CHUNK);
1223	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1224				   XFS_INODES_PER_CHUNK) == 0);
1225	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1226	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1227	rec.ir_freecount--;
1228	error = xfs_inobt_update(cur, &rec);
1229	if (error)
1230		goto error0;
1231	be32_add_cpu(&agi->agi_freecount, -1);
1232	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1233	pag->pagi_freecount--;
1234
1235	error = xfs_check_agi_freecount(cur);
1236	if (error)
1237		goto error0;
1238
1239	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1240	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1241	*inop = ino;
1242	return 0;
1243error1:
1244	xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1245error0:
1246	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1247	return error;
1248}
1249
1250/*
1251 * Use the free inode btree to allocate an inode based on distance from the
1252 * parent. Note that the provided cursor may be deleted and replaced.
1253 */
1254STATIC int
1255xfs_dialloc_ag_finobt_near(
1256	xfs_agino_t			pagino,
1257	struct xfs_btree_cur		**ocur,
1258	struct xfs_inobt_rec_incore	*rec)
1259{
1260	struct xfs_btree_cur		*lcur = *ocur;	/* left search cursor */
1261	struct xfs_btree_cur		*rcur;	/* right search cursor */
1262	struct xfs_inobt_rec_incore	rrec;
1263	int				error;
1264	int				i, j;
1265
1266	error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
1267	if (error)
1268		return error;
1269
1270	if (i == 1) {
1271		error = xfs_inobt_get_rec(lcur, rec, &i);
1272		if (error)
1273			return error;
1274		if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1))
1275			return -EFSCORRUPTED;
1276
1277		/*
1278		 * See if we've landed in the parent inode record. The finobt
1279		 * only tracks chunks with at least one free inode, so record
1280		 * existence is enough.
1281		 */
1282		if (pagino >= rec->ir_startino &&
1283		    pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
1284			return 0;
1285	}
1286
1287	error = xfs_btree_dup_cursor(lcur, &rcur);
1288	if (error)
1289		return error;
1290
1291	error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
1292	if (error)
1293		goto error_rcur;
1294	if (j == 1) {
1295		error = xfs_inobt_get_rec(rcur, &rrec, &j);
1296		if (error)
1297			goto error_rcur;
1298		if (XFS_IS_CORRUPT(lcur->bc_mp, j != 1)) {
1299			error = -EFSCORRUPTED;
1300			goto error_rcur;
1301		}
1302	}
1303
1304	if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1 && j != 1)) {
1305		error = -EFSCORRUPTED;
1306		goto error_rcur;
1307	}
1308	if (i == 1 && j == 1) {
1309		/*
1310		 * Both the left and right records are valid. Choose the closer
1311		 * inode chunk to the target.
1312		 */
1313		if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
1314		    (rrec.ir_startino - pagino)) {
1315			*rec = rrec;
1316			xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1317			*ocur = rcur;
1318		} else {
1319			xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1320		}
1321	} else if (j == 1) {
1322		/* only the right record is valid */
1323		*rec = rrec;
1324		xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1325		*ocur = rcur;
1326	} else if (i == 1) {
1327		/* only the left record is valid */
1328		xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1329	}
1330
1331	return 0;
1332
1333error_rcur:
1334	xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
1335	return error;
1336}
1337
1338/*
1339 * Use the free inode btree to find a free inode based on a newino hint. If
1340 * the hint is NULL, find the first free inode in the AG.
1341 */
1342STATIC int
1343xfs_dialloc_ag_finobt_newino(
1344	struct xfs_agi			*agi,
1345	struct xfs_btree_cur		*cur,
1346	struct xfs_inobt_rec_incore	*rec)
1347{
1348	int error;
1349	int i;
1350
1351	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1352		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1353					 XFS_LOOKUP_EQ, &i);
1354		if (error)
1355			return error;
1356		if (i == 1) {
1357			error = xfs_inobt_get_rec(cur, rec, &i);
1358			if (error)
1359				return error;
1360			if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1361				return -EFSCORRUPTED;
1362			return 0;
1363		}
1364	}
1365
1366	/*
1367	 * Find the first inode available in the AG.
1368	 */
1369	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1370	if (error)
1371		return error;
1372	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1373		return -EFSCORRUPTED;
1374
1375	error = xfs_inobt_get_rec(cur, rec, &i);
1376	if (error)
1377		return error;
1378	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1379		return -EFSCORRUPTED;
1380
1381	return 0;
1382}
1383
1384/*
1385 * Update the inobt based on a modification made to the finobt. Also ensure that
1386 * the records from both trees are equivalent post-modification.
1387 */
1388STATIC int
1389xfs_dialloc_ag_update_inobt(
1390	struct xfs_btree_cur		*cur,	/* inobt cursor */
1391	struct xfs_inobt_rec_incore	*frec,	/* finobt record */
1392	int				offset) /* inode offset */
1393{
1394	struct xfs_inobt_rec_incore	rec;
1395	int				error;
1396	int				i;
1397
1398	error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
1399	if (error)
1400		return error;
1401	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1402		return -EFSCORRUPTED;
1403
1404	error = xfs_inobt_get_rec(cur, &rec, &i);
1405	if (error)
1406		return error;
1407	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1408		return -EFSCORRUPTED;
1409	ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
1410				   XFS_INODES_PER_CHUNK) == 0);
1411
1412	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1413	rec.ir_freecount--;
1414
1415	if (XFS_IS_CORRUPT(cur->bc_mp,
1416			   rec.ir_free != frec->ir_free ||
1417			   rec.ir_freecount != frec->ir_freecount))
1418		return -EFSCORRUPTED;
1419
1420	return xfs_inobt_update(cur, &rec);
1421}
1422
1423/*
1424 * Allocate an inode using the free inode btree, if available. Otherwise, fall
1425 * back to the inobt search algorithm.
1426 *
1427 * The caller selected an AG for us, and made sure that free inodes are
1428 * available.
1429 */
1430static int
1431xfs_dialloc_ag(
1432	struct xfs_trans	*tp,
1433	struct xfs_buf		*agbp,
1434	struct xfs_perag	*pag,
1435	xfs_ino_t		parent,
1436	xfs_ino_t		*inop)
1437{
1438	struct xfs_mount		*mp = tp->t_mountp;
1439	struct xfs_agi			*agi = agbp->b_addr;
 
1440	xfs_agnumber_t			pagno = XFS_INO_TO_AGNO(mp, parent);
1441	xfs_agino_t			pagino = XFS_INO_TO_AGINO(mp, parent);
1442	struct xfs_btree_cur		*cur;	/* finobt cursor */
1443	struct xfs_btree_cur		*icur;	/* inobt cursor */
1444	struct xfs_inobt_rec_incore	rec;
1445	xfs_ino_t			ino;
1446	int				error;
1447	int				offset;
1448	int				i;
1449
1450	if (!xfs_has_finobt(mp))
1451		return xfs_dialloc_ag_inobt(tp, agbp, pag, parent, inop);
1452
1453	/*
1454	 * If pagino is 0 (this is the root inode allocation) use newino.
1455	 * This must work because we've just allocated some.
1456	 */
1457	if (!pagino)
1458		pagino = be32_to_cpu(agi->agi_newino);
1459
1460	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_FINO);
1461
1462	error = xfs_check_agi_freecount(cur);
1463	if (error)
1464		goto error_cur;
1465
1466	/*
1467	 * The search algorithm depends on whether we're in the same AG as the
1468	 * parent. If so, find the closest available inode to the parent. If
1469	 * not, consider the agi hint or find the first free inode in the AG.
1470	 */
1471	if (pag->pag_agno == pagno)
1472		error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
1473	else
1474		error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
1475	if (error)
1476		goto error_cur;
1477
1478	offset = xfs_inobt_first_free_inode(&rec);
1479	ASSERT(offset >= 0);
1480	ASSERT(offset < XFS_INODES_PER_CHUNK);
1481	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1482				   XFS_INODES_PER_CHUNK) == 0);
1483	ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, rec.ir_startino + offset);
1484
1485	/*
1486	 * Modify or remove the finobt record.
1487	 */
1488	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1489	rec.ir_freecount--;
1490	if (rec.ir_freecount)
1491		error = xfs_inobt_update(cur, &rec);
1492	else
1493		error = xfs_btree_delete(cur, &i);
1494	if (error)
1495		goto error_cur;
1496
1497	/*
1498	 * The finobt has now been updated appropriately. We haven't updated the
1499	 * agi and superblock yet, so we can create an inobt cursor and validate
1500	 * the original freecount. If all is well, make the equivalent update to
1501	 * the inobt using the finobt record and offset information.
1502	 */
1503	icur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1504
1505	error = xfs_check_agi_freecount(icur);
1506	if (error)
1507		goto error_icur;
1508
1509	error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
1510	if (error)
1511		goto error_icur;
1512
1513	/*
1514	 * Both trees have now been updated. We must update the perag and
1515	 * superblock before we can check the freecount for each btree.
1516	 */
1517	be32_add_cpu(&agi->agi_freecount, -1);
1518	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1519	pag->pagi_freecount--;
1520
1521	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1522
1523	error = xfs_check_agi_freecount(icur);
1524	if (error)
1525		goto error_icur;
1526	error = xfs_check_agi_freecount(cur);
1527	if (error)
1528		goto error_icur;
1529
1530	xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
1531	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1532	*inop = ino;
1533	return 0;
1534
1535error_icur:
1536	xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
1537error_cur:
1538	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1539	return error;
1540}
1541
1542static int
1543xfs_dialloc_roll(
1544	struct xfs_trans	**tpp,
1545	struct xfs_buf		*agibp)
1546{
1547	struct xfs_trans	*tp = *tpp;
1548	struct xfs_dquot_acct	*dqinfo;
1549	int			error;
1550
1551	/*
1552	 * Hold to on to the agibp across the commit so no other allocation can
1553	 * come in and take the free inodes we just allocated for our caller.
1554	 */
1555	xfs_trans_bhold(tp, agibp);
1556
1557	/*
1558	 * We want the quota changes to be associated with the next transaction,
1559	 * NOT this one. So, detach the dqinfo from this and attach it to the
1560	 * next transaction.
1561	 */
1562	dqinfo = tp->t_dqinfo;
1563	tp->t_dqinfo = NULL;
1564
1565	error = xfs_trans_roll(&tp);
1566
1567	/* Re-attach the quota info that we detached from prev trx. */
1568	tp->t_dqinfo = dqinfo;
1569
1570	/*
1571	 * Join the buffer even on commit error so that the buffer is released
1572	 * when the caller cancels the transaction and doesn't have to handle
1573	 * this error case specially.
1574	 */
1575	xfs_trans_bjoin(tp, agibp);
1576	*tpp = tp;
1577	return error;
1578}
1579
1580static xfs_agnumber_t
1581xfs_ialloc_next_ag(
1582	xfs_mount_t	*mp)
1583{
1584	xfs_agnumber_t	agno;
1585
1586	spin_lock(&mp->m_agirotor_lock);
1587	agno = mp->m_agirotor;
1588	if (++mp->m_agirotor >= mp->m_maxagi)
1589		mp->m_agirotor = 0;
1590	spin_unlock(&mp->m_agirotor_lock);
1591
1592	return agno;
1593}
1594
1595static bool
1596xfs_dialloc_good_ag(
1597	struct xfs_trans	*tp,
1598	struct xfs_perag	*pag,
1599	umode_t			mode,
1600	int			flags,
1601	bool			ok_alloc)
1602{
1603	struct xfs_mount	*mp = tp->t_mountp;
1604	xfs_extlen_t		ineed;
1605	xfs_extlen_t		longest = 0;
1606	int			needspace;
1607	int			error;
1608
1609	if (!pag->pagi_inodeok)
1610		return false;
1611
1612	if (!pag->pagi_init) {
1613		error = xfs_ialloc_read_agi(pag, tp, NULL);
1614		if (error)
1615			return false;
1616	}
1617
1618	if (pag->pagi_freecount)
1619		return true;
1620	if (!ok_alloc)
1621		return false;
1622
1623	if (!pag->pagf_init) {
1624		error = xfs_alloc_read_agf(pag, tp, flags, NULL);
1625		if (error)
1626			return false;
1627	}
1628
1629	/*
1630	 * Check that there is enough free space for the file plus a chunk of
1631	 * inodes if we need to allocate some. If this is the first pass across
1632	 * the AGs, take into account the potential space needed for alignment
1633	 * of inode chunks when checking the longest contiguous free space in
1634	 * the AG - this prevents us from getting ENOSPC because we have free
1635	 * space larger than ialloc_blks but alignment constraints prevent us
1636	 * from using it.
1637	 *
1638	 * If we can't find an AG with space for full alignment slack to be
1639	 * taken into account, we must be near ENOSPC in all AGs.  Hence we
1640	 * don't include alignment for the second pass and so if we fail
1641	 * allocation due to alignment issues then it is most likely a real
1642	 * ENOSPC condition.
1643	 *
1644	 * XXX(dgc): this calculation is now bogus thanks to the per-ag
1645	 * reservations that xfs_alloc_fix_freelist() now does via
1646	 * xfs_alloc_space_available(). When the AG fills up, pagf_freeblks will
1647	 * be more than large enough for the check below to succeed, but
1648	 * xfs_alloc_space_available() will fail because of the non-zero
1649	 * metadata reservation and hence we won't actually be able to allocate
1650	 * more inodes in this AG. We do soooo much unnecessary work near ENOSPC
1651	 * because of this.
1652	 */
1653	ineed = M_IGEO(mp)->ialloc_min_blks;
1654	if (flags && ineed > 1)
1655		ineed += M_IGEO(mp)->cluster_align;
1656	longest = pag->pagf_longest;
1657	if (!longest)
1658		longest = pag->pagf_flcount > 0;
1659	needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
1660
1661	if (pag->pagf_freeblks < needspace + ineed || longest < ineed)
1662		return false;
1663	return true;
1664}
1665
1666static int
1667xfs_dialloc_try_ag(
1668	struct xfs_trans	**tpp,
1669	struct xfs_perag	*pag,
1670	xfs_ino_t		parent,
1671	xfs_ino_t		*new_ino,
1672	bool			ok_alloc)
1673{
1674	struct xfs_buf		*agbp;
1675	xfs_ino_t		ino;
1676	int			error;
1677
1678	/*
1679	 * Then read in the AGI buffer and recheck with the AGI buffer
1680	 * lock held.
1681	 */
1682	error = xfs_ialloc_read_agi(pag, *tpp, &agbp);
1683	if (error)
1684		return error;
1685
1686	if (!pag->pagi_freecount) {
1687		if (!ok_alloc) {
1688			error = -EAGAIN;
1689			goto out_release;
1690		}
1691
1692		error = xfs_ialloc_ag_alloc(*tpp, agbp, pag);
1693		if (error < 0)
1694			goto out_release;
1695
1696		/*
1697		 * We successfully allocated space for an inode cluster in this
1698		 * AG.  Roll the transaction so that we can allocate one of the
1699		 * new inodes.
1700		 */
1701		ASSERT(pag->pagi_freecount > 0);
1702		error = xfs_dialloc_roll(tpp, agbp);
1703		if (error)
1704			goto out_release;
1705	}
1706
1707	/* Allocate an inode in the found AG */
1708	error = xfs_dialloc_ag(*tpp, agbp, pag, parent, &ino);
1709	if (!error)
1710		*new_ino = ino;
1711	return error;
1712
1713out_release:
1714	xfs_trans_brelse(*tpp, agbp);
1715	return error;
1716}
1717
1718/*
1719 * Allocate an on-disk inode.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1720 *
1721 * Mode is used to tell whether the new inode is a directory and hence where to
1722 * locate it. The on-disk inode that is allocated will be returned in @new_ino
1723 * on success, otherwise an error will be set to indicate the failure (e.g.
1724 * -ENOSPC).
1725 */
1726int
1727xfs_dialloc(
1728	struct xfs_trans	**tpp,
1729	xfs_ino_t		parent,
1730	umode_t			mode,
1731	xfs_ino_t		*new_ino)
 
1732{
1733	struct xfs_mount	*mp = (*tpp)->t_mountp;
 
1734	xfs_agnumber_t		agno;
1735	int			error = 0;
 
 
1736	xfs_agnumber_t		start_agno;
1737	struct xfs_perag	*pag;
1738	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
1739	bool			ok_alloc = true;
1740	int			flags;
1741	xfs_ino_t		ino;
 
 
 
 
 
 
 
 
1742
1743	/*
1744	 * Directories, symlinks, and regular files frequently allocate at least
1745	 * one block, so factor that potential expansion when we examine whether
1746	 * an AG has enough space for file creation.
1747	 */
1748	if (S_ISDIR(mode))
1749		start_agno = xfs_ialloc_next_ag(mp);
1750	else {
1751		start_agno = XFS_INO_TO_AGNO(mp, parent);
1752		if (start_agno >= mp->m_maxagi)
1753			start_agno = 0;
1754	}
1755
1756	/*
1757	 * If we have already hit the ceiling of inode blocks then clear
1758	 * ok_alloc so we scan all available agi structures for a free
1759	 * inode.
1760	 *
1761	 * Read rough value of mp->m_icount by percpu_counter_read_positive,
1762	 * which will sacrifice the preciseness but improve the performance.
1763	 */
1764	if (igeo->maxicount &&
1765	    percpu_counter_read_positive(&mp->m_icount) + igeo->ialloc_inos
1766							> igeo->maxicount) {
1767		ok_alloc = false;
 
1768	}
1769
1770	/*
1771	 * Loop until we find an allocation group that either has free inodes
1772	 * or in which we can allocate some inodes.  Iterate through the
1773	 * allocation groups upward, wrapping at the end.
1774	 */
1775	agno = start_agno;
1776	flags = XFS_ALLOC_FLAG_TRYLOCK;
1777	for (;;) {
1778		pag = xfs_perag_get(mp, agno);
1779		if (xfs_dialloc_good_ag(*tpp, pag, mode, flags, ok_alloc)) {
1780			error = xfs_dialloc_try_ag(tpp, pag, parent,
1781					&ino, ok_alloc);
1782			if (error != -EAGAIN)
1783				break;
1784		}
1785
1786		if (xfs_is_shutdown(mp)) {
1787			error = -EFSCORRUPTED;
1788			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1789		}
1790		if (++agno == mp->m_maxagi)
 
 
 
 
 
1791			agno = 0;
1792		if (agno == start_agno) {
1793			if (!flags) {
1794				error = -ENOSPC;
1795				break;
1796			}
1797			flags = 0;
1798		}
1799		xfs_perag_put(pag);
1800	}
1801
1802	if (!error)
1803		*new_ino = ino;
 
 
1804	xfs_perag_put(pag);
1805	return error;
1806}
1807
1808/*
1809 * Free the blocks of an inode chunk. We must consider that the inode chunk
1810 * might be sparse and only free the regions that are allocated as part of the
1811 * chunk.
1812 */
1813STATIC void
1814xfs_difree_inode_chunk(
1815	struct xfs_trans		*tp,
1816	xfs_agnumber_t			agno,
1817	struct xfs_inobt_rec_incore	*rec)
1818{
1819	struct xfs_mount		*mp = tp->t_mountp;
1820	xfs_agblock_t			sagbno = XFS_AGINO_TO_AGBNO(mp,
1821							rec->ir_startino);
1822	int				startidx, endidx;
1823	int				nextbit;
1824	xfs_agblock_t			agbno;
1825	int				contigblk;
1826	DECLARE_BITMAP(holemask, XFS_INOBT_HOLEMASK_BITS);
1827
1828	if (!xfs_inobt_issparse(rec->ir_holemask)) {
1829		/* not sparse, calculate extent info directly */
1830		xfs_free_extent_later(tp, XFS_AGB_TO_FSB(mp, agno, sagbno),
1831				  M_IGEO(mp)->ialloc_blks,
1832				  &XFS_RMAP_OINFO_INODES);
1833		return;
1834	}
1835
1836	/* holemask is only 16-bits (fits in an unsigned long) */
1837	ASSERT(sizeof(rec->ir_holemask) <= sizeof(holemask[0]));
1838	holemask[0] = rec->ir_holemask;
1839
1840	/*
1841	 * Find contiguous ranges of zeroes (i.e., allocated regions) in the
1842	 * holemask and convert the start/end index of each range to an extent.
1843	 * We start with the start and end index both pointing at the first 0 in
1844	 * the mask.
1845	 */
1846	startidx = endidx = find_first_zero_bit(holemask,
1847						XFS_INOBT_HOLEMASK_BITS);
1848	nextbit = startidx + 1;
1849	while (startidx < XFS_INOBT_HOLEMASK_BITS) {
1850		nextbit = find_next_zero_bit(holemask, XFS_INOBT_HOLEMASK_BITS,
1851					     nextbit);
1852		/*
1853		 * If the next zero bit is contiguous, update the end index of
1854		 * the current range and continue.
1855		 */
1856		if (nextbit != XFS_INOBT_HOLEMASK_BITS &&
1857		    nextbit == endidx + 1) {
1858			endidx = nextbit;
1859			goto next;
1860		}
1861
1862		/*
1863		 * nextbit is not contiguous with the current end index. Convert
1864		 * the current start/end to an extent and add it to the free
1865		 * list.
1866		 */
1867		agbno = sagbno + (startidx * XFS_INODES_PER_HOLEMASK_BIT) /
1868				  mp->m_sb.sb_inopblock;
1869		contigblk = ((endidx - startidx + 1) *
1870			     XFS_INODES_PER_HOLEMASK_BIT) /
1871			    mp->m_sb.sb_inopblock;
1872
1873		ASSERT(agbno % mp->m_sb.sb_spino_align == 0);
1874		ASSERT(contigblk % mp->m_sb.sb_spino_align == 0);
1875		xfs_free_extent_later(tp, XFS_AGB_TO_FSB(mp, agno, agbno),
1876				  contigblk, &XFS_RMAP_OINFO_INODES);
1877
1878		/* reset range to current bit and carry on... */
1879		startidx = endidx = nextbit;
1880
1881next:
1882		nextbit++;
1883	}
1884}
1885
1886STATIC int
1887xfs_difree_inobt(
1888	struct xfs_mount		*mp,
1889	struct xfs_trans		*tp,
1890	struct xfs_buf			*agbp,
1891	struct xfs_perag		*pag,
1892	xfs_agino_t			agino,
1893	struct xfs_icluster		*xic,
1894	struct xfs_inobt_rec_incore	*orec)
1895{
1896	struct xfs_agi			*agi = agbp->b_addr;
 
1897	struct xfs_btree_cur		*cur;
1898	struct xfs_inobt_rec_incore	rec;
1899	int				ilen;
1900	int				error;
1901	int				i;
1902	int				off;
1903
1904	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1905	ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
1906
1907	/*
1908	 * Initialize the cursor.
1909	 */
1910	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
1911
1912	error = xfs_check_agi_freecount(cur);
1913	if (error)
1914		goto error0;
1915
1916	/*
1917	 * Look for the entry describing this inode.
1918	 */
1919	if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1920		xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1921			__func__, error);
1922		goto error0;
1923	}
1924	if (XFS_IS_CORRUPT(mp, i != 1)) {
1925		error = -EFSCORRUPTED;
1926		goto error0;
1927	}
1928	error = xfs_inobt_get_rec(cur, &rec, &i);
1929	if (error) {
1930		xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1931			__func__, error);
1932		goto error0;
1933	}
1934	if (XFS_IS_CORRUPT(mp, i != 1)) {
1935		error = -EFSCORRUPTED;
1936		goto error0;
1937	}
1938	/*
1939	 * Get the offset in the inode chunk.
1940	 */
1941	off = agino - rec.ir_startino;
1942	ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1943	ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1944	/*
1945	 * Mark the inode free & increment the count.
1946	 */
1947	rec.ir_free |= XFS_INOBT_MASK(off);
1948	rec.ir_freecount++;
1949
1950	/*
1951	 * When an inode chunk is free, it becomes eligible for removal. Don't
1952	 * remove the chunk if the block size is large enough for multiple inode
1953	 * chunks (that might not be free).
1954	 */
1955	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
 
1956	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
1957		struct xfs_perag	*pag = agbp->b_pag;
1958
1959		xic->deleted = true;
1960		xic->first_ino = XFS_AGINO_TO_INO(mp, pag->pag_agno,
1961				rec.ir_startino);
1962		xic->alloc = xfs_inobt_irec_to_allocmask(&rec);
1963
1964		/*
1965		 * Remove the inode cluster from the AGI B+Tree, adjust the
1966		 * AGI and Superblock inode counts, and mark the disk space
1967		 * to be freed when the transaction is committed.
1968		 */
1969		ilen = rec.ir_freecount;
1970		be32_add_cpu(&agi->agi_count, -ilen);
1971		be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
1972		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
1973		pag->pagi_freecount -= ilen - 1;
1974		pag->pagi_count -= ilen;
1975		xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
1976		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
1977
1978		if ((error = xfs_btree_delete(cur, &i))) {
1979			xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
1980				__func__, error);
1981			goto error0;
1982		}
1983
1984		xfs_difree_inode_chunk(tp, pag->pag_agno, &rec);
1985	} else {
1986		xic->deleted = false;
1987
1988		error = xfs_inobt_update(cur, &rec);
1989		if (error) {
1990			xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
1991				__func__, error);
1992			goto error0;
1993		}
1994
1995		/*
1996		 * Change the inode free counts and log the ag/sb changes.
1997		 */
1998		be32_add_cpu(&agi->agi_freecount, 1);
1999		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
2000		pag->pagi_freecount++;
2001		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
2002	}
2003
2004	error = xfs_check_agi_freecount(cur);
2005	if (error)
2006		goto error0;
2007
2008	*orec = rec;
2009	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2010	return 0;
2011
2012error0:
2013	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2014	return error;
2015}
2016
2017/*
2018 * Free an inode in the free inode btree.
2019 */
2020STATIC int
2021xfs_difree_finobt(
2022	struct xfs_mount		*mp,
2023	struct xfs_trans		*tp,
2024	struct xfs_buf			*agbp,
2025	struct xfs_perag		*pag,
2026	xfs_agino_t			agino,
2027	struct xfs_inobt_rec_incore	*ibtrec) /* inobt record */
2028{
 
 
2029	struct xfs_btree_cur		*cur;
2030	struct xfs_inobt_rec_incore	rec;
2031	int				offset = agino - ibtrec->ir_startino;
2032	int				error;
2033	int				i;
2034
2035	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_FINO);
2036
2037	error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
2038	if (error)
2039		goto error;
2040	if (i == 0) {
2041		/*
2042		 * If the record does not exist in the finobt, we must have just
2043		 * freed an inode in a previously fully allocated chunk. If not,
2044		 * something is out of sync.
2045		 */
2046		if (XFS_IS_CORRUPT(mp, ibtrec->ir_freecount != 1)) {
2047			error = -EFSCORRUPTED;
2048			goto error;
2049		}
2050
2051		error = xfs_inobt_insert_rec(cur, ibtrec->ir_holemask,
2052					     ibtrec->ir_count,
2053					     ibtrec->ir_freecount,
2054					     ibtrec->ir_free, &i);
2055		if (error)
2056			goto error;
2057		ASSERT(i == 1);
2058
2059		goto out;
2060	}
2061
2062	/*
2063	 * Read and update the existing record. We could just copy the ibtrec
2064	 * across here, but that would defeat the purpose of having redundant
2065	 * metadata. By making the modifications independently, we can catch
2066	 * corruptions that we wouldn't see if we just copied from one record
2067	 * to another.
2068	 */
2069	error = xfs_inobt_get_rec(cur, &rec, &i);
2070	if (error)
2071		goto error;
2072	if (XFS_IS_CORRUPT(mp, i != 1)) {
2073		error = -EFSCORRUPTED;
2074		goto error;
2075	}
2076
2077	rec.ir_free |= XFS_INOBT_MASK(offset);
2078	rec.ir_freecount++;
2079
2080	if (XFS_IS_CORRUPT(mp,
2081			   rec.ir_free != ibtrec->ir_free ||
2082			   rec.ir_freecount != ibtrec->ir_freecount)) {
2083		error = -EFSCORRUPTED;
2084		goto error;
2085	}
2086
2087	/*
2088	 * The content of inobt records should always match between the inobt
2089	 * and finobt. The lifecycle of records in the finobt is different from
2090	 * the inobt in that the finobt only tracks records with at least one
2091	 * free inode. Hence, if all of the inodes are free and we aren't
2092	 * keeping inode chunks permanently on disk, remove the record.
2093	 * Otherwise, update the record with the new information.
2094	 *
2095	 * Note that we currently can't free chunks when the block size is large
2096	 * enough for multiple chunks. Leave the finobt record to remain in sync
2097	 * with the inobt.
2098	 */
2099	if (!xfs_has_ikeep(mp) && rec.ir_free == XFS_INOBT_ALL_FREE &&
2100	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
 
2101		error = xfs_btree_delete(cur, &i);
2102		if (error)
2103			goto error;
2104		ASSERT(i == 1);
2105	} else {
2106		error = xfs_inobt_update(cur, &rec);
2107		if (error)
2108			goto error;
2109	}
2110
2111out:
2112	error = xfs_check_agi_freecount(cur);
2113	if (error)
2114		goto error;
2115
2116	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2117	return 0;
2118
2119error:
2120	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2121	return error;
2122}
2123
2124/*
2125 * Free disk inode.  Carefully avoids touching the incore inode, all
2126 * manipulations incore are the caller's responsibility.
2127 * The on-disk inode is not changed by this operation, only the
2128 * btree (free inode mask) is changed.
2129 */
2130int
2131xfs_difree(
2132	struct xfs_trans	*tp,
2133	struct xfs_perag	*pag,
2134	xfs_ino_t		inode,
2135	struct xfs_icluster	*xic)
2136{
2137	/* REFERENCED */
2138	xfs_agblock_t		agbno;	/* block number containing inode */
2139	struct xfs_buf		*agbp;	/* buffer for allocation group header */
2140	xfs_agino_t		agino;	/* allocation group inode number */
 
2141	int			error;	/* error return value */
2142	struct xfs_mount	*mp = tp->t_mountp;
2143	struct xfs_inobt_rec_incore rec;/* btree record */
2144
 
 
2145	/*
2146	 * Break up inode number into its components.
2147	 */
2148	if (pag->pag_agno != XFS_INO_TO_AGNO(mp, inode)) {
2149		xfs_warn(mp, "%s: agno != pag->pag_agno (%d != %d).",
2150			__func__, XFS_INO_TO_AGNO(mp, inode), pag->pag_agno);
 
2151		ASSERT(0);
2152		return -EINVAL;
2153	}
2154	agino = XFS_INO_TO_AGINO(mp, inode);
2155	if (inode != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino))  {
2156		xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
2157			__func__, (unsigned long long)inode,
2158			(unsigned long long)XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2159		ASSERT(0);
2160		return -EINVAL;
2161	}
2162	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2163	if (agbno >= mp->m_sb.sb_agblocks)  {
2164		xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
2165			__func__, agbno, mp->m_sb.sb_agblocks);
2166		ASSERT(0);
2167		return -EINVAL;
2168	}
2169	/*
2170	 * Get the allocation group header.
2171	 */
2172	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2173	if (error) {
2174		xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
2175			__func__, error);
2176		return error;
2177	}
2178
2179	/*
2180	 * Fix up the inode allocation btree.
2181	 */
2182	error = xfs_difree_inobt(mp, tp, agbp, pag, agino, xic, &rec);
2183	if (error)
2184		goto error0;
2185
2186	/*
2187	 * Fix up the free inode btree.
2188	 */
2189	if (xfs_has_finobt(mp)) {
2190		error = xfs_difree_finobt(mp, tp, agbp, pag, agino, &rec);
2191		if (error)
2192			goto error0;
2193	}
2194
2195	return 0;
2196
2197error0:
2198	return error;
2199}
2200
2201STATIC int
2202xfs_imap_lookup(
2203	struct xfs_mount	*mp,
2204	struct xfs_trans	*tp,
2205	struct xfs_perag	*pag,
2206	xfs_agino_t		agino,
2207	xfs_agblock_t		agbno,
2208	xfs_agblock_t		*chunk_agbno,
2209	xfs_agblock_t		*offset_agbno,
2210	int			flags)
2211{
2212	struct xfs_inobt_rec_incore rec;
2213	struct xfs_btree_cur	*cur;
2214	struct xfs_buf		*agbp;
2215	int			error;
2216	int			i;
2217
2218	error = xfs_ialloc_read_agi(pag, tp, &agbp);
2219	if (error) {
2220		xfs_alert(mp,
2221			"%s: xfs_ialloc_read_agi() returned error %d, agno %d",
2222			__func__, error, pag->pag_agno);
2223		return error;
2224	}
2225
2226	/*
2227	 * Lookup the inode record for the given agino. If the record cannot be
2228	 * found, then it's an invalid inode number and we should abort. Once
2229	 * we have a record, we need to ensure it contains the inode number
2230	 * we are looking up.
2231	 */
2232	cur = xfs_inobt_init_cursor(mp, tp, agbp, pag, XFS_BTNUM_INO);
2233	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
2234	if (!error) {
2235		if (i)
2236			error = xfs_inobt_get_rec(cur, &rec, &i);
2237		if (!error && i == 0)
2238			error = -EINVAL;
2239	}
2240
2241	xfs_trans_brelse(tp, agbp);
2242	xfs_btree_del_cursor(cur, error);
2243	if (error)
2244		return error;
2245
2246	/* check that the returned record contains the required inode */
2247	if (rec.ir_startino > agino ||
2248	    rec.ir_startino + M_IGEO(mp)->ialloc_inos <= agino)
2249		return -EINVAL;
2250
2251	/* for untrusted inodes check it is allocated first */
2252	if ((flags & XFS_IGET_UNTRUSTED) &&
2253	    (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
2254		return -EINVAL;
2255
2256	*chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
2257	*offset_agbno = agbno - *chunk_agbno;
2258	return 0;
2259}
2260
2261/*
2262 * Return the location of the inode in imap, for mapping it into a buffer.
2263 */
2264int
2265xfs_imap(
2266	struct xfs_mount	 *mp,	/* file system mount structure */
2267	struct xfs_trans	 *tp,	/* transaction pointer */
2268	xfs_ino_t		ino,	/* inode to locate */
2269	struct xfs_imap		*imap,	/* location map structure */
2270	uint			flags)	/* flags for inode btree lookup */
2271{
2272	xfs_agblock_t		agbno;	/* block number of inode in the alloc group */
2273	xfs_agino_t		agino;	/* inode number within alloc group */
2274	xfs_agblock_t		chunk_agbno;	/* first block in inode chunk */
2275	xfs_agblock_t		cluster_agbno;	/* first block in inode cluster */
2276	int			error;	/* error code */
2277	int			offset;	/* index of inode in its buffer */
2278	xfs_agblock_t		offset_agbno;	/* blks from chunk start to inode */
2279	struct xfs_perag	*pag;
2280
2281	ASSERT(ino != NULLFSINO);
2282
2283	/*
2284	 * Split up the inode number into its parts.
2285	 */
2286	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ino));
2287	agino = XFS_INO_TO_AGINO(mp, ino);
2288	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2289	if (!pag || agbno >= mp->m_sb.sb_agblocks ||
2290	    ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2291		error = -EINVAL;
2292#ifdef DEBUG
2293		/*
2294		 * Don't output diagnostic information for untrusted inodes
2295		 * as they can be invalid without implying corruption.
2296		 */
2297		if (flags & XFS_IGET_UNTRUSTED)
2298			goto out_drop;
2299		if (!pag) {
2300			xfs_alert(mp,
2301				"%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
2302				__func__, XFS_INO_TO_AGNO(mp, ino),
2303				mp->m_sb.sb_agcount);
2304		}
2305		if (agbno >= mp->m_sb.sb_agblocks) {
2306			xfs_alert(mp,
2307		"%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
2308				__func__, (unsigned long long)agbno,
2309				(unsigned long)mp->m_sb.sb_agblocks);
2310		}
2311		if (pag && ino != XFS_AGINO_TO_INO(mp, pag->pag_agno, agino)) {
2312			xfs_alert(mp,
2313		"%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
2314				__func__, ino,
2315				XFS_AGINO_TO_INO(mp, pag->pag_agno, agino));
2316		}
2317		xfs_stack_trace();
2318#endif /* DEBUG */
2319		goto out_drop;
2320	}
2321
2322	/*
2323	 * For bulkstat and handle lookups, we have an untrusted inode number
2324	 * that we have to verify is valid. We cannot do this just by reading
2325	 * the inode buffer as it may have been unlinked and removed leaving
2326	 * inodes in stale state on disk. Hence we have to do a btree lookup
2327	 * in all cases where an untrusted inode number is passed.
2328	 */
2329	if (flags & XFS_IGET_UNTRUSTED) {
2330		error = xfs_imap_lookup(mp, tp, pag, agino, agbno,
2331					&chunk_agbno, &offset_agbno, flags);
2332		if (error)
2333			goto out_drop;
2334		goto out_map;
2335	}
2336
2337	/*
2338	 * If the inode cluster size is the same as the blocksize or
2339	 * smaller we get to the buffer by simple arithmetics.
2340	 */
2341	if (M_IGEO(mp)->blocks_per_cluster == 1) {
2342		offset = XFS_INO_TO_OFFSET(mp, ino);
2343		ASSERT(offset < mp->m_sb.sb_inopblock);
2344
2345		imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, agbno);
2346		imap->im_len = XFS_FSB_TO_BB(mp, 1);
2347		imap->im_boffset = (unsigned short)(offset <<
2348							mp->m_sb.sb_inodelog);
2349		error = 0;
2350		goto out_drop;
2351	}
2352
2353	/*
2354	 * If the inode chunks are aligned then use simple maths to
2355	 * find the location. Otherwise we have to do a btree
2356	 * lookup to find the location.
2357	 */
2358	if (M_IGEO(mp)->inoalign_mask) {
2359		offset_agbno = agbno & M_IGEO(mp)->inoalign_mask;
2360		chunk_agbno = agbno - offset_agbno;
2361	} else {
2362		error = xfs_imap_lookup(mp, tp, pag, agino, agbno,
2363					&chunk_agbno, &offset_agbno, flags);
2364		if (error)
2365			goto out_drop;
2366	}
2367
2368out_map:
2369	ASSERT(agbno >= chunk_agbno);
2370	cluster_agbno = chunk_agbno +
2371		((offset_agbno / M_IGEO(mp)->blocks_per_cluster) *
2372		 M_IGEO(mp)->blocks_per_cluster);
2373	offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
2374		XFS_INO_TO_OFFSET(mp, ino);
2375
2376	imap->im_blkno = XFS_AGB_TO_DADDR(mp, pag->pag_agno, cluster_agbno);
2377	imap->im_len = XFS_FSB_TO_BB(mp, M_IGEO(mp)->blocks_per_cluster);
2378	imap->im_boffset = (unsigned short)(offset << mp->m_sb.sb_inodelog);
2379
2380	/*
2381	 * If the inode number maps to a block outside the bounds
2382	 * of the file system then return NULL rather than calling
2383	 * read_buf and panicing when we get an error from the
2384	 * driver.
2385	 */
2386	if ((imap->im_blkno + imap->im_len) >
2387	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
2388		xfs_alert(mp,
2389	"%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
2390			__func__, (unsigned long long) imap->im_blkno,
2391			(unsigned long long) imap->im_len,
2392			XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
2393		error = -EINVAL;
2394		goto out_drop;
2395	}
2396	error = 0;
2397out_drop:
2398	if (pag)
2399		xfs_perag_put(pag);
2400	return error;
2401}
2402
2403/*
2404 * Log specified fields for the ag hdr (inode section). The growth of the agi
2405 * structure over time requires that we interpret the buffer as two logical
2406 * regions delineated by the end of the unlinked list. This is due to the size
2407 * of the hash table and its location in the middle of the agi.
2408 *
2409 * For example, a request to log a field before agi_unlinked and a field after
2410 * agi_unlinked could cause us to log the entire hash table and use an excessive
2411 * amount of log space. To avoid this behavior, log the region up through
2412 * agi_unlinked in one call and the region after agi_unlinked through the end of
2413 * the structure in another.
2414 */
2415void
2416xfs_ialloc_log_agi(
2417	struct xfs_trans	*tp,
2418	struct xfs_buf		*bp,
2419	uint32_t		fields)
2420{
2421	int			first;		/* first byte number */
2422	int			last;		/* last byte number */
2423	static const short	offsets[] = {	/* field starting offsets */
2424					/* keep in sync with bit definitions */
2425		offsetof(xfs_agi_t, agi_magicnum),
2426		offsetof(xfs_agi_t, agi_versionnum),
2427		offsetof(xfs_agi_t, agi_seqno),
2428		offsetof(xfs_agi_t, agi_length),
2429		offsetof(xfs_agi_t, agi_count),
2430		offsetof(xfs_agi_t, agi_root),
2431		offsetof(xfs_agi_t, agi_level),
2432		offsetof(xfs_agi_t, agi_freecount),
2433		offsetof(xfs_agi_t, agi_newino),
2434		offsetof(xfs_agi_t, agi_dirino),
2435		offsetof(xfs_agi_t, agi_unlinked),
2436		offsetof(xfs_agi_t, agi_free_root),
2437		offsetof(xfs_agi_t, agi_free_level),
2438		offsetof(xfs_agi_t, agi_iblocks),
2439		sizeof(xfs_agi_t)
2440	};
2441#ifdef DEBUG
2442	struct xfs_agi		*agi = bp->b_addr;
2443
2444	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2445#endif
2446
2447	/*
2448	 * Compute byte offsets for the first and last fields in the first
2449	 * region and log the agi buffer. This only logs up through
2450	 * agi_unlinked.
2451	 */
2452	if (fields & XFS_AGI_ALL_BITS_R1) {
2453		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
2454				  &first, &last);
2455		xfs_trans_log_buf(tp, bp, first, last);
2456	}
2457
2458	/*
2459	 * Mask off the bits in the first region and calculate the first and
2460	 * last field offsets for any bits in the second region.
2461	 */
2462	fields &= ~XFS_AGI_ALL_BITS_R1;
2463	if (fields) {
2464		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
2465				  &first, &last);
2466		xfs_trans_log_buf(tp, bp, first, last);
2467	}
2468}
2469
2470static xfs_failaddr_t
2471xfs_agi_verify(
2472	struct xfs_buf	*bp)
2473{
2474	struct xfs_mount *mp = bp->b_mount;
2475	struct xfs_agi	*agi = bp->b_addr;
2476	int		i;
2477
2478	if (xfs_has_crc(mp)) {
2479		if (!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid))
2480			return __this_address;
2481		if (!xfs_log_check_lsn(mp, be64_to_cpu(agi->agi_lsn)))
2482			return __this_address;
2483	}
2484
2485	/*
2486	 * Validate the magic number of the agi block.
2487	 */
2488	if (!xfs_verify_magic(bp, agi->agi_magicnum))
2489		return __this_address;
2490	if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
2491		return __this_address;
2492
2493	if (be32_to_cpu(agi->agi_level) < 1 ||
2494	    be32_to_cpu(agi->agi_level) > M_IGEO(mp)->inobt_maxlevels)
2495		return __this_address;
2496
2497	if (xfs_has_finobt(mp) &&
2498	    (be32_to_cpu(agi->agi_free_level) < 1 ||
2499	     be32_to_cpu(agi->agi_free_level) > M_IGEO(mp)->inobt_maxlevels))
2500		return __this_address;
2501
2502	/*
2503	 * during growfs operations, the perag is not fully initialised,
2504	 * so we can't use it for any useful checking. growfs ensures we can't
2505	 * use it by using uncached buffers that don't have the perag attached
2506	 * so we can detect and avoid this problem.
2507	 */
2508	if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
2509		return __this_address;
2510
2511	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
2512		if (agi->agi_unlinked[i] == cpu_to_be32(NULLAGINO))
2513			continue;
2514		if (!xfs_verify_ino(mp, be32_to_cpu(agi->agi_unlinked[i])))
2515			return __this_address;
2516	}
2517
2518	return NULL;
2519}
2520
2521static void
2522xfs_agi_read_verify(
2523	struct xfs_buf	*bp)
2524{
2525	struct xfs_mount *mp = bp->b_mount;
2526	xfs_failaddr_t	fa;
2527
2528	if (xfs_has_crc(mp) &&
2529	    !xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
2530		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
2531	else {
2532		fa = xfs_agi_verify(bp);
2533		if (XFS_TEST_ERROR(fa, mp, XFS_ERRTAG_IALLOC_READ_AGI))
2534			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2535	}
2536}
2537
2538static void
2539xfs_agi_write_verify(
2540	struct xfs_buf	*bp)
2541{
2542	struct xfs_mount	*mp = bp->b_mount;
2543	struct xfs_buf_log_item	*bip = bp->b_log_item;
2544	struct xfs_agi		*agi = bp->b_addr;
2545	xfs_failaddr_t		fa;
2546
2547	fa = xfs_agi_verify(bp);
2548	if (fa) {
2549		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2550		return;
2551	}
2552
2553	if (!xfs_has_crc(mp))
2554		return;
2555
2556	if (bip)
2557		agi->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2558	xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
2559}
2560
2561const struct xfs_buf_ops xfs_agi_buf_ops = {
2562	.name = "xfs_agi",
2563	.magic = { cpu_to_be32(XFS_AGI_MAGIC), cpu_to_be32(XFS_AGI_MAGIC) },
2564	.verify_read = xfs_agi_read_verify,
2565	.verify_write = xfs_agi_write_verify,
2566	.verify_struct = xfs_agi_verify,
2567};
2568
2569/*
2570 * Read in the allocation group header (inode allocation section)
2571 */
2572int
2573xfs_read_agi(
2574	struct xfs_perag	*pag,
2575	struct xfs_trans	*tp,
2576	struct xfs_buf		**agibpp)
 
2577{
2578	struct xfs_mount	*mp = pag->pag_mount;
2579	int			error;
2580
2581	trace_xfs_read_agi(pag->pag_mount, pag->pag_agno);
2582
 
2583	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
2584			XFS_AG_DADDR(mp, pag->pag_agno, XFS_AGI_DADDR(mp)),
2585			XFS_FSS_TO_BB(mp, 1), 0, agibpp, &xfs_agi_buf_ops);
2586	if (error)
2587		return error;
2588	if (tp)
2589		xfs_trans_buf_set_type(tp, *agibpp, XFS_BLFT_AGI_BUF);
2590
2591	xfs_buf_set_ref(*agibpp, XFS_AGI_REF);
2592	return 0;
2593}
2594
2595/*
2596 * Read in the agi and initialise the per-ag data. If the caller supplies a
2597 * @agibpp, return the locked AGI buffer to them, otherwise release it.
2598 */
2599int
2600xfs_ialloc_read_agi(
2601	struct xfs_perag	*pag,
2602	struct xfs_trans	*tp,
2603	struct xfs_buf		**agibpp)
 
2604{
2605	struct xfs_buf		*agibp;
2606	struct xfs_agi		*agi;
2607	int			error;
2608
2609	trace_xfs_ialloc_read_agi(pag->pag_mount, pag->pag_agno);
2610
2611	error = xfs_read_agi(pag, tp, &agibp);
2612	if (error)
2613		return error;
2614
2615	agi = agibp->b_addr;
 
2616	if (!pag->pagi_init) {
2617		pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
2618		pag->pagi_count = be32_to_cpu(agi->agi_count);
2619		pag->pagi_init = 1;
2620	}
2621
2622	/*
2623	 * It's possible for these to be out of sync if
2624	 * we are in the middle of a forced shutdown.
2625	 */
2626	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
2627		xfs_is_shutdown(pag->pag_mount));
2628	if (agibpp)
2629		*agibpp = agibp;
2630	else
2631		xfs_trans_brelse(tp, agibp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2632	return 0;
2633}
2634
2635/* Is there an inode record covering a given range of inode numbers? */
2636int
2637xfs_ialloc_has_inode_record(
2638	struct xfs_btree_cur	*cur,
2639	xfs_agino_t		low,
2640	xfs_agino_t		high,
2641	bool			*exists)
2642{
2643	struct xfs_inobt_rec_incore	irec;
2644	xfs_agino_t		agino;
2645	uint16_t		holemask;
2646	int			has_record;
2647	int			i;
2648	int			error;
2649
2650	*exists = false;
2651	error = xfs_inobt_lookup(cur, low, XFS_LOOKUP_LE, &has_record);
2652	while (error == 0 && has_record) {
2653		error = xfs_inobt_get_rec(cur, &irec, &has_record);
2654		if (error || irec.ir_startino > high)
2655			break;
2656
2657		agino = irec.ir_startino;
2658		holemask = irec.ir_holemask;
2659		for (i = 0; i < XFS_INOBT_HOLEMASK_BITS; holemask >>= 1,
2660				i++, agino += XFS_INODES_PER_HOLEMASK_BIT) {
2661			if (holemask & 1)
2662				continue;
2663			if (agino + XFS_INODES_PER_HOLEMASK_BIT > low &&
2664					agino <= high) {
2665				*exists = true;
2666				return 0;
2667			}
2668		}
2669
2670		error = xfs_btree_increment(cur, 0, &has_record);
2671	}
2672	return error;
2673}
2674
2675/* Is there an inode record covering a given extent? */
2676int
2677xfs_ialloc_has_inodes_at_extent(
2678	struct xfs_btree_cur	*cur,
2679	xfs_agblock_t		bno,
2680	xfs_extlen_t		len,
2681	bool			*exists)
2682{
2683	xfs_agino_t		low;
2684	xfs_agino_t		high;
2685
2686	low = XFS_AGB_TO_AGINO(cur->bc_mp, bno);
2687	high = XFS_AGB_TO_AGINO(cur->bc_mp, bno + len) - 1;
2688
2689	return xfs_ialloc_has_inode_record(cur, low, high, exists);
2690}
2691
2692struct xfs_ialloc_count_inodes {
2693	xfs_agino_t			count;
2694	xfs_agino_t			freecount;
2695};
2696
2697/* Record inode counts across all inobt records. */
2698STATIC int
2699xfs_ialloc_count_inodes_rec(
2700	struct xfs_btree_cur		*cur,
2701	const union xfs_btree_rec	*rec,
2702	void				*priv)
2703{
2704	struct xfs_inobt_rec_incore	irec;
2705	struct xfs_ialloc_count_inodes	*ci = priv;
2706
2707	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
2708	ci->count += irec.ir_count;
2709	ci->freecount += irec.ir_freecount;
2710
2711	return 0;
2712}
2713
2714/* Count allocated and free inodes under an inobt. */
2715int
2716xfs_ialloc_count_inodes(
2717	struct xfs_btree_cur		*cur,
2718	xfs_agino_t			*count,
2719	xfs_agino_t			*freecount)
2720{
2721	struct xfs_ialloc_count_inodes	ci = {0};
2722	int				error;
2723
2724	ASSERT(cur->bc_btnum == XFS_BTNUM_INO);
2725	error = xfs_btree_query_all(cur, xfs_ialloc_count_inodes_rec, &ci);
2726	if (error)
2727		return error;
2728
2729	*count = ci.count;
2730	*freecount = ci.freecount;
2731	return 0;
2732}
2733
2734/*
2735 * Initialize inode-related geometry information.
2736 *
2737 * Compute the inode btree min and max levels and set maxicount.
2738 *
2739 * Set the inode cluster size.  This may still be overridden by the file
2740 * system block size if it is larger than the chosen cluster size.
2741 *
2742 * For v5 filesystems, scale the cluster size with the inode size to keep a
2743 * constant ratio of inode per cluster buffer, but only if mkfs has set the
2744 * inode alignment value appropriately for larger cluster sizes.
2745 *
2746 * Then compute the inode cluster alignment information.
2747 */
2748void
2749xfs_ialloc_setup_geometry(
2750	struct xfs_mount	*mp)
2751{
2752	struct xfs_sb		*sbp = &mp->m_sb;
2753	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2754	uint64_t		icount;
2755	uint			inodes;
2756
2757	igeo->new_diflags2 = 0;
2758	if (xfs_has_bigtime(mp))
2759		igeo->new_diflags2 |= XFS_DIFLAG2_BIGTIME;
2760	if (xfs_has_large_extent_counts(mp))
2761		igeo->new_diflags2 |= XFS_DIFLAG2_NREXT64;
2762
2763	/* Compute inode btree geometry. */
2764	igeo->agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
2765	igeo->inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
2766	igeo->inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
2767	igeo->inobt_mnr[0] = igeo->inobt_mxr[0] / 2;
2768	igeo->inobt_mnr[1] = igeo->inobt_mxr[1] / 2;
2769
2770	igeo->ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK,
2771			sbp->sb_inopblock);
2772	igeo->ialloc_blks = igeo->ialloc_inos >> sbp->sb_inopblog;
2773
2774	if (sbp->sb_spino_align)
2775		igeo->ialloc_min_blks = sbp->sb_spino_align;
2776	else
2777		igeo->ialloc_min_blks = igeo->ialloc_blks;
2778
2779	/* Compute and fill in value of m_ino_geo.inobt_maxlevels. */
2780	inodes = (1LL << XFS_INO_AGINO_BITS(mp)) >> XFS_INODES_PER_CHUNK_LOG;
2781	igeo->inobt_maxlevels = xfs_btree_compute_maxlevels(igeo->inobt_mnr,
2782			inodes);
2783	ASSERT(igeo->inobt_maxlevels <= xfs_iallocbt_maxlevels_ondisk());
2784
2785	/*
2786	 * Set the maximum inode count for this filesystem, being careful not
2787	 * to use obviously garbage sb_inopblog/sb_inopblock values.  Regular
2788	 * users should never get here due to failing sb verification, but
2789	 * certain users (xfs_db) need to be usable even with corrupt metadata.
2790	 */
2791	if (sbp->sb_imax_pct && igeo->ialloc_blks) {
2792		/*
2793		 * Make sure the maximum inode count is a multiple
2794		 * of the units we allocate inodes in.
2795		 */
2796		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
2797		do_div(icount, 100);
2798		do_div(icount, igeo->ialloc_blks);
2799		igeo->maxicount = XFS_FSB_TO_INO(mp,
2800				icount * igeo->ialloc_blks);
2801	} else {
2802		igeo->maxicount = 0;
2803	}
2804
2805	/*
2806	 * Compute the desired size of an inode cluster buffer size, which
2807	 * starts at 8K and (on v5 filesystems) scales up with larger inode
2808	 * sizes.
2809	 *
2810	 * Preserve the desired inode cluster size because the sparse inodes
2811	 * feature uses that desired size (not the actual size) to compute the
2812	 * sparse inode alignment.  The mount code validates this value, so we
2813	 * cannot change the behavior.
2814	 */
2815	igeo->inode_cluster_size_raw = XFS_INODE_BIG_CLUSTER_SIZE;
2816	if (xfs_has_v3inodes(mp)) {
2817		int	new_size = igeo->inode_cluster_size_raw;
2818
2819		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
2820		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
2821			igeo->inode_cluster_size_raw = new_size;
2822	}
2823
2824	/* Calculate inode cluster ratios. */
2825	if (igeo->inode_cluster_size_raw > mp->m_sb.sb_blocksize)
2826		igeo->blocks_per_cluster = XFS_B_TO_FSBT(mp,
2827				igeo->inode_cluster_size_raw);
2828	else
2829		igeo->blocks_per_cluster = 1;
2830	igeo->inode_cluster_size = XFS_FSB_TO_B(mp, igeo->blocks_per_cluster);
2831	igeo->inodes_per_cluster = XFS_FSB_TO_INO(mp, igeo->blocks_per_cluster);
2832
2833	/* Calculate inode cluster alignment. */
2834	if (xfs_has_align(mp) &&
2835	    mp->m_sb.sb_inoalignmt >= igeo->blocks_per_cluster)
2836		igeo->cluster_align = mp->m_sb.sb_inoalignmt;
2837	else
2838		igeo->cluster_align = 1;
2839	igeo->inoalign_mask = igeo->cluster_align - 1;
2840	igeo->cluster_align_inodes = XFS_FSB_TO_INO(mp, igeo->cluster_align);
2841
2842	/*
2843	 * If we are using stripe alignment, check whether
2844	 * the stripe unit is a multiple of the inode alignment
2845	 */
2846	if (mp->m_dalign && igeo->inoalign_mask &&
2847	    !(mp->m_dalign & igeo->inoalign_mask))
2848		igeo->ialloc_align = mp->m_dalign;
2849	else
2850		igeo->ialloc_align = 0;
2851}
2852
2853/* Compute the location of the root directory inode that is laid out by mkfs. */
2854xfs_ino_t
2855xfs_ialloc_calc_rootino(
2856	struct xfs_mount	*mp,
2857	int			sunit)
2858{
2859	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2860	xfs_agblock_t		first_bno;
2861
2862	/*
2863	 * Pre-calculate the geometry of AG 0.  We know what it looks like
2864	 * because libxfs knows how to create allocation groups now.
2865	 *
2866	 * first_bno is the first block in which mkfs could possibly have
2867	 * allocated the root directory inode, once we factor in the metadata
2868	 * that mkfs formats before it.  Namely, the four AG headers...
2869	 */
2870	first_bno = howmany(4 * mp->m_sb.sb_sectsize, mp->m_sb.sb_blocksize);
2871
2872	/* ...the two free space btree roots... */
2873	first_bno += 2;
2874
2875	/* ...the inode btree root... */
2876	first_bno += 1;
2877
2878	/* ...the initial AGFL... */
2879	first_bno += xfs_alloc_min_freelist(mp, NULL);
2880
2881	/* ...the free inode btree root... */
2882	if (xfs_has_finobt(mp))
2883		first_bno++;
2884
2885	/* ...the reverse mapping btree root... */
2886	if (xfs_has_rmapbt(mp))
2887		first_bno++;
2888
2889	/* ...the reference count btree... */
2890	if (xfs_has_reflink(mp))
2891		first_bno++;
2892
2893	/*
2894	 * ...and the log, if it is allocated in the first allocation group.
2895	 *
2896	 * This can happen with filesystems that only have a single
2897	 * allocation group, or very odd geometries created by old mkfs
2898	 * versions on very small filesystems.
2899	 */
2900	if (xfs_ag_contains_log(mp, 0))
 
2901		 first_bno += mp->m_sb.sb_logblocks;
2902
2903	/*
2904	 * Now round first_bno up to whatever allocation alignment is given
2905	 * by the filesystem or was passed in.
2906	 */
2907	if (xfs_has_dalign(mp) && igeo->ialloc_align > 0)
2908		first_bno = roundup(first_bno, sunit);
2909	else if (xfs_has_align(mp) &&
2910			mp->m_sb.sb_inoalignmt > 1)
2911		first_bno = roundup(first_bno, mp->m_sb.sb_inoalignmt);
2912
2913	return XFS_AGINO_TO_INO(mp, 0, XFS_AGB_TO_AGINO(mp, first_bno));
2914}
2915
2916/*
2917 * Ensure there are not sparse inode clusters that cross the new EOAG.
2918 *
2919 * This is a no-op for non-spinode filesystems since clusters are always fully
2920 * allocated and checking the bnobt suffices.  However, a spinode filesystem
2921 * could have a record where the upper inodes are free blocks.  If those blocks
2922 * were removed from the filesystem, the inode record would extend beyond EOAG,
2923 * which will be flagged as corruption.
2924 */
2925int
2926xfs_ialloc_check_shrink(
2927	struct xfs_trans	*tp,
2928	xfs_agnumber_t		agno,
2929	struct xfs_buf		*agibp,
2930	xfs_agblock_t		new_length)
2931{
2932	struct xfs_inobt_rec_incore rec;
2933	struct xfs_btree_cur	*cur;
2934	struct xfs_mount	*mp = tp->t_mountp;
2935	struct xfs_perag	*pag;
2936	xfs_agino_t		agino = XFS_AGB_TO_AGINO(mp, new_length);
2937	int			has;
2938	int			error;
2939
2940	if (!xfs_has_sparseinodes(mp))
2941		return 0;
2942
2943	pag = xfs_perag_get(mp, agno);
2944	cur = xfs_inobt_init_cursor(mp, tp, agibp, pag, XFS_BTNUM_INO);
2945
2946	/* Look up the inobt record that would correspond to the new EOFS. */
2947	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &has);
2948	if (error || !has)
2949		goto out;
2950
2951	error = xfs_inobt_get_rec(cur, &rec, &has);
2952	if (error)
2953		goto out;
2954
2955	if (!has) {
2956		error = -EFSCORRUPTED;
2957		goto out;
2958	}
2959
2960	/* If the record covers inodes that would be beyond EOFS, bail out. */
2961	if (rec.ir_startino + XFS_INODES_PER_CHUNK > agino) {
2962		error = -ENOSPC;
2963		goto out;
2964	}
2965out:
2966	xfs_btree_del_cursor(cur, error);
2967	xfs_perag_put(pag);
2968	return error;
2969}
v5.9
   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_sb.h"
  14#include "xfs_mount.h"
  15#include "xfs_inode.h"
  16#include "xfs_btree.h"
  17#include "xfs_ialloc.h"
  18#include "xfs_ialloc_btree.h"
  19#include "xfs_alloc.h"
  20#include "xfs_errortag.h"
  21#include "xfs_error.h"
  22#include "xfs_bmap.h"
  23#include "xfs_trans.h"
  24#include "xfs_buf_item.h"
  25#include "xfs_icreate_item.h"
  26#include "xfs_icache.h"
  27#include "xfs_trace.h"
  28#include "xfs_log.h"
  29#include "xfs_rmap.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.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	xfs_agino_t		newino,
 176	xfs_agino_t		newlen,
 177	xfs_btnum_t		btnum)
 178{
 179	struct xfs_btree_cur	*cur;
 180	struct xfs_agi		*agi = agbp->b_addr;
 181	xfs_agnumber_t		agno = be32_to_cpu(agi->agi_seqno);
 182	xfs_agino_t		thisino;
 183	int			i;
 184	int			error;
 185
 186	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, btnum);
 187
 188	for (thisino = newino;
 189	     thisino < newino + newlen;
 190	     thisino += XFS_INODES_PER_CHUNK) {
 191		error = xfs_inobt_lookup(cur, thisino, XFS_LOOKUP_EQ, &i);
 192		if (error) {
 193			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 194			return error;
 195		}
 196		ASSERT(i == 0);
 197
 198		error = xfs_inobt_insert_rec(cur, XFS_INOBT_HOLEMASK_FULL,
 199					     XFS_INODES_PER_CHUNK,
 200					     XFS_INODES_PER_CHUNK,
 201					     XFS_INOBT_ALL_FREE, &i);
 202		if (error) {
 203			xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 204			return error;
 205		}
 206		ASSERT(i == 1);
 207	}
 208
 209	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 210
 211	return 0;
 212}
 213
 214/*
 215 * Verify that the number of free inodes in the AGI is correct.
 216 */
 217#ifdef DEBUG
 218STATIC int
 219xfs_check_agi_freecount(
 220	struct xfs_btree_cur	*cur,
 221	struct xfs_agi		*agi)
 222{
 223	if (cur->bc_nlevels == 1) {
 224		xfs_inobt_rec_incore_t rec;
 225		int		freecount = 0;
 226		int		error;
 227		int		i;
 228
 229		error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
 230		if (error)
 231			return error;
 232
 233		do {
 234			error = xfs_inobt_get_rec(cur, &rec, &i);
 235			if (error)
 236				return error;
 237
 238			if (i) {
 239				freecount += rec.ir_freecount;
 240				error = xfs_btree_increment(cur, 0, &i);
 241				if (error)
 242					return error;
 243			}
 244		} while (i == 1);
 245
 246		if (!XFS_FORCED_SHUTDOWN(cur->bc_mp))
 247			ASSERT(freecount == be32_to_cpu(agi->agi_freecount));
 248	}
 249	return 0;
 250}
 251#else
 252#define xfs_check_agi_freecount(cur, agi)	0
 253#endif
 254
 255/*
 256 * Initialise a new set of inodes. When called without a transaction context
 257 * (e.g. from recovery) we initiate a delayed write of the inode buffers rather
 258 * than logging them (which in a transaction context puts them into the AIL
 259 * for writeback rather than the xfsbufd queue).
 260 */
 261int
 262xfs_ialloc_inode_init(
 263	struct xfs_mount	*mp,
 264	struct xfs_trans	*tp,
 265	struct list_head	*buffer_list,
 266	int			icount,
 267	xfs_agnumber_t		agno,
 268	xfs_agblock_t		agbno,
 269	xfs_agblock_t		length,
 270	unsigned int		gen)
 271{
 272	struct xfs_buf		*fbuf;
 273	struct xfs_dinode	*free;
 274	int			nbufs;
 275	int			version;
 276	int			i, j;
 277	xfs_daddr_t		d;
 278	xfs_ino_t		ino = 0;
 279	int			error;
 280
 281	/*
 282	 * Loop over the new block(s), filling in the inodes.  For small block
 283	 * sizes, manipulate the inodes in buffers  which are multiples of the
 284	 * blocks size.
 285	 */
 286	nbufs = length / M_IGEO(mp)->blocks_per_cluster;
 287
 288	/*
 289	 * Figure out what version number to use in the inodes we create.  If
 290	 * the superblock version has caught up to the one that supports the new
 291	 * inode format, then use the new inode version.  Otherwise use the old
 292	 * version so that old kernels will continue to be able to use the file
 293	 * system.
 294	 *
 295	 * For v3 inodes, we also need to write the inode number into the inode,
 296	 * so calculate the first inode number of the chunk here as
 297	 * XFS_AGB_TO_AGINO() only works within a filesystem block, not
 298	 * across multiple filesystem blocks (such as a cluster) and so cannot
 299	 * be used in the cluster buffer loop below.
 300	 *
 301	 * Further, because we are writing the inode directly into the buffer
 302	 * and calculating a CRC on the entire inode, we have ot log the entire
 303	 * inode so that the entire range the CRC covers is present in the log.
 304	 * That means for v3 inode we log the entire buffer rather than just the
 305	 * inode cores.
 306	 */
 307	if (xfs_sb_version_has_v3inode(&mp->m_sb)) {
 308		version = 3;
 309		ino = XFS_AGINO_TO_INO(mp, agno, XFS_AGB_TO_AGINO(mp, agbno));
 310
 311		/*
 312		 * log the initialisation that is about to take place as an
 313		 * logical operation. This means the transaction does not
 314		 * need to log the physical changes to the inode buffers as log
 315		 * recovery will know what initialisation is actually needed.
 316		 * Hence we only need to log the buffers as "ordered" buffers so
 317		 * they track in the AIL as if they were physically logged.
 318		 */
 319		if (tp)
 320			xfs_icreate_log(tp, agno, agbno, icount,
 321					mp->m_sb.sb_inodesize, length, gen);
 322	} else
 323		version = 2;
 324
 325	for (j = 0; j < nbufs; j++) {
 326		/*
 327		 * Get the block.
 328		 */
 329		d = XFS_AGB_TO_DADDR(mp, agno, agbno +
 330				(j * M_IGEO(mp)->blocks_per_cluster));
 331		error = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
 332				mp->m_bsize * M_IGEO(mp)->blocks_per_cluster,
 333				XBF_UNMAPPED, &fbuf);
 334		if (error)
 335			return error;
 336
 337		/* Initialize the inode buffers and log them appropriately. */
 338		fbuf->b_ops = &xfs_inode_buf_ops;
 339		xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
 340		for (i = 0; i < M_IGEO(mp)->inodes_per_cluster; i++) {
 341			int	ioffset = i << mp->m_sb.sb_inodelog;
 342			uint	isize = XFS_DINODE_SIZE(&mp->m_sb);
 343
 344			free = xfs_make_iptr(mp, fbuf, i);
 345			free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
 346			free->di_version = version;
 347			free->di_gen = cpu_to_be32(gen);
 348			free->di_next_unlinked = cpu_to_be32(NULLAGINO);
 349
 350			if (version == 3) {
 351				free->di_ino = cpu_to_be64(ino);
 352				ino++;
 353				uuid_copy(&free->di_uuid,
 354					  &mp->m_sb.sb_meta_uuid);
 355				xfs_dinode_calc_crc(mp, free);
 356			} else if (tp) {
 357				/* just log the inode core */
 358				xfs_trans_log_buf(tp, fbuf, ioffset,
 359						  ioffset + isize - 1);
 360			}
 361		}
 362
 363		if (tp) {
 364			/*
 365			 * Mark the buffer as an inode allocation buffer so it
 366			 * sticks in AIL at the point of this allocation
 367			 * transaction. This ensures the they are on disk before
 368			 * the tail of the log can be moved past this
 369			 * transaction (i.e. by preventing relogging from moving
 370			 * it forward in the log).
 371			 */
 372			xfs_trans_inode_alloc_buf(tp, fbuf);
 373			if (version == 3) {
 374				/*
 375				 * Mark the buffer as ordered so that they are
 376				 * not physically logged in the transaction but
 377				 * still tracked in the AIL as part of the
 378				 * transaction and pin the log appropriately.
 379				 */
 380				xfs_trans_ordered_buf(tp, fbuf);
 381			}
 382		} else {
 383			fbuf->b_flags |= XBF_DONE;
 384			xfs_buf_delwri_queue(fbuf, buffer_list);
 385			xfs_buf_relse(fbuf);
 386		}
 387	}
 388	return 0;
 389}
 390
 391/*
 392 * Align startino and allocmask for a recently allocated sparse chunk such that
 393 * they are fit for insertion (or merge) into the on-disk inode btrees.
 394 *
 395 * Background:
 396 *
 397 * When enabled, sparse inode support increases the inode alignment from cluster
 398 * size to inode chunk size. This means that the minimum range between two
 399 * non-adjacent inode records in the inobt is large enough for a full inode
 400 * record. This allows for cluster sized, cluster aligned block allocation
 401 * without need to worry about whether the resulting inode record overlaps with
 402 * another record in the tree. Without this basic rule, we would have to deal
 403 * with the consequences of overlap by potentially undoing recent allocations in
 404 * the inode allocation codepath.
 405 *
 406 * Because of this alignment rule (which is enforced on mount), there are two
 407 * inobt possibilities for newly allocated sparse chunks. One is that the
 408 * aligned inode record for the chunk covers a range of inodes not already
 409 * covered in the inobt (i.e., it is safe to insert a new sparse record). The
 410 * other is that a record already exists at the aligned startino that considers
 411 * the newly allocated range as sparse. In the latter case, record content is
 412 * merged in hope that sparse inode chunks fill to full chunks over time.
 413 */
 414STATIC void
 415xfs_align_sparse_ino(
 416	struct xfs_mount		*mp,
 417	xfs_agino_t			*startino,
 418	uint16_t			*allocmask)
 419{
 420	xfs_agblock_t			agbno;
 421	xfs_agblock_t			mod;
 422	int				offset;
 423
 424	agbno = XFS_AGINO_TO_AGBNO(mp, *startino);
 425	mod = agbno % mp->m_sb.sb_inoalignmt;
 426	if (!mod)
 427		return;
 428
 429	/* calculate the inode offset and align startino */
 430	offset = XFS_AGB_TO_AGINO(mp, mod);
 431	*startino -= offset;
 432
 433	/*
 434	 * Since startino has been aligned down, left shift allocmask such that
 435	 * it continues to represent the same physical inodes relative to the
 436	 * new startino.
 437	 */
 438	*allocmask <<= offset / XFS_INODES_PER_HOLEMASK_BIT;
 439}
 440
 441/*
 442 * Determine whether the source inode record can merge into the target. Both
 443 * records must be sparse, the inode ranges must match and there must be no
 444 * allocation overlap between the records.
 445 */
 446STATIC bool
 447__xfs_inobt_can_merge(
 448	struct xfs_inobt_rec_incore	*trec,	/* tgt record */
 449	struct xfs_inobt_rec_incore	*srec)	/* src record */
 450{
 451	uint64_t			talloc;
 452	uint64_t			salloc;
 453
 454	/* records must cover the same inode range */
 455	if (trec->ir_startino != srec->ir_startino)
 456		return false;
 457
 458	/* both records must be sparse */
 459	if (!xfs_inobt_issparse(trec->ir_holemask) ||
 460	    !xfs_inobt_issparse(srec->ir_holemask))
 461		return false;
 462
 463	/* both records must track some inodes */
 464	if (!trec->ir_count || !srec->ir_count)
 465		return false;
 466
 467	/* can't exceed capacity of a full record */
 468	if (trec->ir_count + srec->ir_count > XFS_INODES_PER_CHUNK)
 469		return false;
 470
 471	/* verify there is no allocation overlap */
 472	talloc = xfs_inobt_irec_to_allocmask(trec);
 473	salloc = xfs_inobt_irec_to_allocmask(srec);
 474	if (talloc & salloc)
 475		return false;
 476
 477	return true;
 478}
 479
 480/*
 481 * Merge the source inode record into the target. The caller must call
 482 * __xfs_inobt_can_merge() to ensure the merge is valid.
 483 */
 484STATIC void
 485__xfs_inobt_rec_merge(
 486	struct xfs_inobt_rec_incore	*trec,	/* target */
 487	struct xfs_inobt_rec_incore	*srec)	/* src */
 488{
 489	ASSERT(trec->ir_startino == srec->ir_startino);
 490
 491	/* combine the counts */
 492	trec->ir_count += srec->ir_count;
 493	trec->ir_freecount += srec->ir_freecount;
 494
 495	/*
 496	 * Merge the holemask and free mask. For both fields, 0 bits refer to
 497	 * allocated inodes. We combine the allocated ranges with bitwise AND.
 498	 */
 499	trec->ir_holemask &= srec->ir_holemask;
 500	trec->ir_free &= srec->ir_free;
 501}
 502
 503/*
 504 * Insert a new sparse inode chunk into the associated inode btree. The inode
 505 * record for the sparse chunk is pre-aligned to a startino that should match
 506 * any pre-existing sparse inode record in the tree. This allows sparse chunks
 507 * to fill over time.
 508 *
 509 * This function supports two modes of handling preexisting records depending on
 510 * the merge flag. If merge is true, the provided record is merged with the
 511 * existing record and updated in place. The merged record is returned in nrec.
 512 * If merge is false, an existing record is replaced with the provided record.
 513 * If no preexisting record exists, the provided record is always inserted.
 514 *
 515 * It is considered corruption if a merge is requested and not possible. Given
 516 * the sparse inode alignment constraints, this should never happen.
 517 */
 518STATIC int
 519xfs_inobt_insert_sprec(
 520	struct xfs_mount		*mp,
 521	struct xfs_trans		*tp,
 522	struct xfs_buf			*agbp,
 
 523	int				btnum,
 524	struct xfs_inobt_rec_incore	*nrec,	/* in/out: new/merged rec. */
 525	bool				merge)	/* merge or replace */
 526{
 527	struct xfs_btree_cur		*cur;
 528	struct xfs_agi			*agi = agbp->b_addr;
 529	xfs_agnumber_t			agno = be32_to_cpu(agi->agi_seqno);
 530	int				error;
 531	int				i;
 532	struct xfs_inobt_rec_incore	rec;
 533
 534	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, btnum);
 535
 536	/* the new record is pre-aligned so we know where to look */
 537	error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
 538	if (error)
 539		goto error;
 540	/* if nothing there, insert a new record and return */
 541	if (i == 0) {
 542		error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
 543					     nrec->ir_count, nrec->ir_freecount,
 544					     nrec->ir_free, &i);
 545		if (error)
 546			goto error;
 547		if (XFS_IS_CORRUPT(mp, i != 1)) {
 548			error = -EFSCORRUPTED;
 549			goto error;
 550		}
 551
 552		goto out;
 553	}
 554
 555	/*
 556	 * A record exists at this startino. Merge or replace the record
 557	 * depending on what we've been asked to do.
 558	 */
 559	if (merge) {
 560		error = xfs_inobt_get_rec(cur, &rec, &i);
 561		if (error)
 562			goto error;
 563		if (XFS_IS_CORRUPT(mp, i != 1)) {
 564			error = -EFSCORRUPTED;
 565			goto error;
 566		}
 567		if (XFS_IS_CORRUPT(mp, rec.ir_startino != nrec->ir_startino)) {
 568			error = -EFSCORRUPTED;
 569			goto error;
 570		}
 571
 572		/*
 573		 * This should never fail. If we have coexisting records that
 574		 * cannot merge, something is seriously wrong.
 575		 */
 576		if (XFS_IS_CORRUPT(mp, !__xfs_inobt_can_merge(nrec, &rec))) {
 577			error = -EFSCORRUPTED;
 578			goto error;
 579		}
 580
 581		trace_xfs_irec_merge_pre(mp, agno, rec.ir_startino,
 582					 rec.ir_holemask, nrec->ir_startino,
 583					 nrec->ir_holemask);
 584
 585		/* merge to nrec to output the updated record */
 586		__xfs_inobt_rec_merge(nrec, &rec);
 587
 588		trace_xfs_irec_merge_post(mp, agno, nrec->ir_startino,
 589					  nrec->ir_holemask);
 590
 591		error = xfs_inobt_rec_check_count(mp, nrec);
 592		if (error)
 593			goto error;
 594	}
 595
 596	error = xfs_inobt_update(cur, nrec);
 597	if (error)
 598		goto error;
 599
 600out:
 601	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 602	return 0;
 603error:
 604	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 605	return error;
 606}
 607
 608/*
 609 * Allocate new inodes in the allocation group specified by agbp.
 610 * Return 0 for success, else error code.
 
 
 611 */
 612STATIC int
 613xfs_ialloc_ag_alloc(
 614	struct xfs_trans	*tp,
 615	struct xfs_buf		*agbp,
 616	int			*alloc)
 617{
 618	struct xfs_agi		*agi;
 619	struct xfs_alloc_arg	args;
 620	xfs_agnumber_t		agno;
 621	int			error;
 622	xfs_agino_t		newino;		/* new first inode's number */
 623	xfs_agino_t		newlen;		/* new number of inodes */
 624	int			isaligned = 0;	/* inode allocation at stripe */
 625						/* unit boundary */
 626	/* init. to full chunk */
 627	uint16_t		allocmask = (uint16_t) -1;
 628	struct xfs_inobt_rec_incore rec;
 629	struct xfs_perag	*pag;
 630	struct xfs_ino_geometry	*igeo = M_IGEO(tp->t_mountp);
 
 631	int			do_sparse = 0;
 632
 633	memset(&args, 0, sizeof(args));
 634	args.tp = tp;
 635	args.mp = tp->t_mountp;
 636	args.fsbno = NULLFSBLOCK;
 637	args.oinfo = XFS_RMAP_OINFO_INODES;
 638
 639#ifdef DEBUG
 640	/* randomly do sparse inode allocations */
 641	if (xfs_sb_version_hassparseinodes(&tp->t_mountp->m_sb) &&
 642	    igeo->ialloc_min_blks < igeo->ialloc_blks)
 643		do_sparse = prandom_u32() & 1;
 644#endif
 645
 646	/*
 647	 * Locking will ensure that we don't have two callers in here
 648	 * at one time.
 649	 */
 650	newlen = igeo->ialloc_inos;
 651	if (igeo->maxicount &&
 652	    percpu_counter_read_positive(&args.mp->m_icount) + newlen >
 653							igeo->maxicount)
 654		return -ENOSPC;
 655	args.minlen = args.maxlen = igeo->ialloc_blks;
 656	/*
 657	 * First try to allocate inodes contiguous with the last-allocated
 658	 * chunk of inodes.  If the filesystem is striped, this will fill
 659	 * an entire stripe unit with inodes.
 660	 */
 661	agi = agbp->b_addr;
 662	newino = be32_to_cpu(agi->agi_newino);
 663	agno = be32_to_cpu(agi->agi_seqno);
 664	args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
 665		     igeo->ialloc_blks;
 666	if (do_sparse)
 667		goto sparse_alloc;
 668	if (likely(newino != NULLAGINO &&
 669		  (args.agbno < be32_to_cpu(agi->agi_length)))) {
 670		args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
 671		args.type = XFS_ALLOCTYPE_THIS_BNO;
 672		args.prod = 1;
 673
 674		/*
 675		 * We need to take into account alignment here to ensure that
 676		 * we don't modify the free list if we fail to have an exact
 677		 * block. If we don't have an exact match, and every oher
 678		 * attempt allocation attempt fails, we'll end up cancelling
 679		 * a dirty transaction and shutting down.
 680		 *
 681		 * For an exact allocation, alignment must be 1,
 682		 * however we need to take cluster alignment into account when
 683		 * fixing up the freelist. Use the minalignslop field to
 684		 * indicate that extra blocks might be required for alignment,
 685		 * but not to use them in the actual exact allocation.
 686		 */
 687		args.alignment = 1;
 688		args.minalignslop = igeo->cluster_align - 1;
 689
 690		/* Allow space for the inode btree to split. */
 691		args.minleft = igeo->inobt_maxlevels;
 692		if ((error = xfs_alloc_vextent(&args)))
 693			return error;
 694
 695		/*
 696		 * This request might have dirtied the transaction if the AG can
 697		 * satisfy the request, but the exact block was not available.
 698		 * If the allocation did fail, subsequent requests will relax
 699		 * the exact agbno requirement and increase the alignment
 700		 * instead. It is critical that the total size of the request
 701		 * (len + alignment + slop) does not increase from this point
 702		 * on, so reset minalignslop to ensure it is not included in
 703		 * subsequent requests.
 704		 */
 705		args.minalignslop = 0;
 706	}
 707
 708	if (unlikely(args.fsbno == NULLFSBLOCK)) {
 709		/*
 710		 * Set the alignment for the allocation.
 711		 * If stripe alignment is turned on then align at stripe unit
 712		 * boundary.
 713		 * If the cluster size is smaller than a filesystem block
 714		 * then we're doing I/O for inodes in filesystem block size
 715		 * pieces, so don't need alignment anyway.
 716		 */
 717		isaligned = 0;
 718		if (igeo->ialloc_align) {
 719			ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
 720			args.alignment = args.mp->m_dalign;
 721			isaligned = 1;
 722		} else
 723			args.alignment = igeo->cluster_align;
 724		/*
 725		 * Need to figure out where to allocate the inode blocks.
 726		 * Ideally they should be spaced out through the a.g.
 727		 * For now, just allocate blocks up front.
 728		 */
 729		args.agbno = be32_to_cpu(agi->agi_root);
 730		args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
 731		/*
 732		 * Allocate a fixed-size extent of inodes.
 733		 */
 734		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 735		args.prod = 1;
 736		/*
 737		 * Allow space for the inode btree to split.
 738		 */
 739		args.minleft = igeo->inobt_maxlevels;
 740		if ((error = xfs_alloc_vextent(&args)))
 741			return error;
 742	}
 743
 744	/*
 745	 * If stripe alignment is turned on, then try again with cluster
 746	 * alignment.
 747	 */
 748	if (isaligned && args.fsbno == NULLFSBLOCK) {
 749		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 750		args.agbno = be32_to_cpu(agi->agi_root);
 751		args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
 752		args.alignment = igeo->cluster_align;
 753		if ((error = xfs_alloc_vextent(&args)))
 754			return error;
 755	}
 756
 757	/*
 758	 * Finally, try a sparse allocation if the filesystem supports it and
 759	 * the sparse allocation length is smaller than a full chunk.
 760	 */
 761	if (xfs_sb_version_hassparseinodes(&args.mp->m_sb) &&
 762	    igeo->ialloc_min_blks < igeo->ialloc_blks &&
 763	    args.fsbno == NULLFSBLOCK) {
 764sparse_alloc:
 765		args.type = XFS_ALLOCTYPE_NEAR_BNO;
 766		args.agbno = be32_to_cpu(agi->agi_root);
 767		args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
 768		args.alignment = args.mp->m_sb.sb_spino_align;
 769		args.prod = 1;
 770
 771		args.minlen = igeo->ialloc_min_blks;
 772		args.maxlen = args.minlen;
 773
 774		/*
 775		 * The inode record will be aligned to full chunk size. We must
 776		 * prevent sparse allocation from AG boundaries that result in
 777		 * invalid inode records, such as records that start at agbno 0
 778		 * or extend beyond the AG.
 779		 *
 780		 * Set min agbno to the first aligned, non-zero agbno and max to
 781		 * the last aligned agbno that is at least one full chunk from
 782		 * the end of the AG.
 783		 */
 784		args.min_agbno = args.mp->m_sb.sb_inoalignmt;
 785		args.max_agbno = round_down(args.mp->m_sb.sb_agblocks,
 786					    args.mp->m_sb.sb_inoalignmt) -
 787				 igeo->ialloc_blks;
 788
 789		error = xfs_alloc_vextent(&args);
 790		if (error)
 791			return error;
 792
 793		newlen = XFS_AGB_TO_AGINO(args.mp, args.len);
 794		ASSERT(newlen <= XFS_INODES_PER_CHUNK);
 795		allocmask = (1 << (newlen / XFS_INODES_PER_HOLEMASK_BIT)) - 1;
 796	}
 797
 798	if (args.fsbno == NULLFSBLOCK) {
 799		*alloc = 0;
 800		return 0;
 801	}
 802	ASSERT(args.len == args.minlen);
 803
 804	/*
 805	 * Stamp and write the inode buffers.
 806	 *
 807	 * Seed the new inode cluster with a random generation number. This
 808	 * prevents short-term reuse of generation numbers if a chunk is
 809	 * freed and then immediately reallocated. We use random numbers
 810	 * rather than a linear progression to prevent the next generation
 811	 * number from being easily guessable.
 812	 */
 813	error = xfs_ialloc_inode_init(args.mp, tp, NULL, newlen, agno,
 814			args.agbno, args.len, prandom_u32());
 815
 816	if (error)
 817		return error;
 818	/*
 819	 * Convert the results.
 820	 */
 821	newino = XFS_AGB_TO_AGINO(args.mp, args.agbno);
 822
 823	if (xfs_inobt_issparse(~allocmask)) {
 824		/*
 825		 * We've allocated a sparse chunk. Align the startino and mask.
 826		 */
 827		xfs_align_sparse_ino(args.mp, &newino, &allocmask);
 828
 829		rec.ir_startino = newino;
 830		rec.ir_holemask = ~allocmask;
 831		rec.ir_count = newlen;
 832		rec.ir_freecount = newlen;
 833		rec.ir_free = XFS_INOBT_ALL_FREE;
 834
 835		/*
 836		 * Insert the sparse record into the inobt and allow for a merge
 837		 * if necessary. If a merge does occur, rec is updated to the
 838		 * merged record.
 839		 */
 840		error = xfs_inobt_insert_sprec(args.mp, tp, agbp, XFS_BTNUM_INO,
 841					       &rec, true);
 842		if (error == -EFSCORRUPTED) {
 843			xfs_alert(args.mp,
 844	"invalid sparse inode record: ino 0x%llx holemask 0x%x count %u",
 845				  XFS_AGINO_TO_INO(args.mp, agno,
 846						   rec.ir_startino),
 847				  rec.ir_holemask, rec.ir_count);
 848			xfs_force_shutdown(args.mp, SHUTDOWN_CORRUPT_INCORE);
 849		}
 850		if (error)
 851			return error;
 852
 853		/*
 854		 * We can't merge the part we've just allocated as for the inobt
 855		 * due to finobt semantics. The original record may or may not
 856		 * exist independent of whether physical inodes exist in this
 857		 * sparse chunk.
 858		 *
 859		 * We must update the finobt record based on the inobt record.
 860		 * rec contains the fully merged and up to date inobt record
 861		 * from the previous call. Set merge false to replace any
 862		 * existing record with this one.
 863		 */
 864		if (xfs_sb_version_hasfinobt(&args.mp->m_sb)) {
 865			error = xfs_inobt_insert_sprec(args.mp, tp, agbp,
 866						       XFS_BTNUM_FINO, &rec,
 867						       false);
 868			if (error)
 869				return error;
 870		}
 871	} else {
 872		/* full chunk - insert new records to both btrees */
 873		error = xfs_inobt_insert(args.mp, tp, agbp, newino, newlen,
 874					 XFS_BTNUM_INO);
 875		if (error)
 876			return error;
 877
 878		if (xfs_sb_version_hasfinobt(&args.mp->m_sb)) {
 879			error = xfs_inobt_insert(args.mp, tp, agbp, newino,
 880						 newlen, XFS_BTNUM_FINO);
 881			if (error)
 882				return error;
 883		}
 884	}
 885
 886	/*
 887	 * Update AGI counts and newino.
 888	 */
 889	be32_add_cpu(&agi->agi_count, newlen);
 890	be32_add_cpu(&agi->agi_freecount, newlen);
 891	pag = agbp->b_pag;
 892	pag->pagi_freecount += newlen;
 893	pag->pagi_count += newlen;
 894	agi->agi_newino = cpu_to_be32(newino);
 895
 896	/*
 897	 * Log allocation group header fields
 898	 */
 899	xfs_ialloc_log_agi(tp, agbp,
 900		XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
 901	/*
 902	 * Modify/log superblock values for inode count and inode free count.
 903	 */
 904	xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
 905	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
 906	*alloc = 1;
 907	return 0;
 908}
 909
 910STATIC xfs_agnumber_t
 911xfs_ialloc_next_ag(
 912	xfs_mount_t	*mp)
 913{
 914	xfs_agnumber_t	agno;
 915
 916	spin_lock(&mp->m_agirotor_lock);
 917	agno = mp->m_agirotor;
 918	if (++mp->m_agirotor >= mp->m_maxagi)
 919		mp->m_agirotor = 0;
 920	spin_unlock(&mp->m_agirotor_lock);
 921
 922	return agno;
 923}
 924
 925/*
 926 * Select an allocation group to look for a free inode in, based on the parent
 927 * inode and the mode.  Return the allocation group buffer.
 928 */
 929STATIC xfs_agnumber_t
 930xfs_ialloc_ag_select(
 931	xfs_trans_t	*tp,		/* transaction pointer */
 932	xfs_ino_t	parent,		/* parent directory inode number */
 933	umode_t		mode)		/* bits set to indicate file type */
 934{
 935	xfs_agnumber_t	agcount;	/* number of ag's in the filesystem */
 936	xfs_agnumber_t	agno;		/* current ag number */
 937	int		flags;		/* alloc buffer locking flags */
 938	xfs_extlen_t	ineed;		/* blocks needed for inode allocation */
 939	xfs_extlen_t	longest = 0;	/* longest extent available */
 940	xfs_mount_t	*mp;		/* mount point structure */
 941	int		needspace;	/* file mode implies space allocated */
 942	xfs_perag_t	*pag;		/* per allocation group data */
 943	xfs_agnumber_t	pagno;		/* parent (starting) ag number */
 944	int		error;
 945
 946	/*
 947	 * Files of these types need at least one block if length > 0
 948	 * (and they won't fit in the inode, but that's hard to figure out).
 949	 */
 950	needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
 951	mp = tp->t_mountp;
 952	agcount = mp->m_maxagi;
 953	if (S_ISDIR(mode))
 954		pagno = xfs_ialloc_next_ag(mp);
 955	else {
 956		pagno = XFS_INO_TO_AGNO(mp, parent);
 957		if (pagno >= agcount)
 958			pagno = 0;
 959	}
 960
 961	ASSERT(pagno < agcount);
 962
 963	/*
 964	 * Loop through allocation groups, looking for one with a little
 965	 * free space in it.  Note we don't look for free inodes, exactly.
 966	 * Instead, we include whether there is a need to allocate inodes
 967	 * to mean that blocks must be allocated for them,
 968	 * if none are currently free.
 969	 */
 970	agno = pagno;
 971	flags = XFS_ALLOC_FLAG_TRYLOCK;
 972	for (;;) {
 973		pag = xfs_perag_get(mp, agno);
 974		if (!pag->pagi_inodeok) {
 975			xfs_ialloc_next_ag(mp);
 976			goto nextag;
 977		}
 978
 979		if (!pag->pagi_init) {
 980			error = xfs_ialloc_pagi_init(mp, tp, agno);
 981			if (error)
 982				goto nextag;
 983		}
 984
 985		if (pag->pagi_freecount) {
 986			xfs_perag_put(pag);
 987			return agno;
 988		}
 989
 990		if (!pag->pagf_init) {
 991			error = xfs_alloc_pagf_init(mp, tp, agno, flags);
 992			if (error)
 993				goto nextag;
 994		}
 995
 996		/*
 997		 * Check that there is enough free space for the file plus a
 998		 * chunk of inodes if we need to allocate some. If this is the
 999		 * first pass across the AGs, take into account the potential
1000		 * space needed for alignment of inode chunks when checking the
1001		 * longest contiguous free space in the AG - this prevents us
1002		 * from getting ENOSPC because we have free space larger than
1003		 * ialloc_blks but alignment constraints prevent us from using
1004		 * it.
1005		 *
1006		 * If we can't find an AG with space for full alignment slack to
1007		 * be taken into account, we must be near ENOSPC in all AGs.
1008		 * Hence we don't include alignment for the second pass and so
1009		 * if we fail allocation due to alignment issues then it is most
1010		 * likely a real ENOSPC condition.
1011		 */
1012		ineed = M_IGEO(mp)->ialloc_min_blks;
1013		if (flags && ineed > 1)
1014			ineed += M_IGEO(mp)->cluster_align;
1015		longest = pag->pagf_longest;
1016		if (!longest)
1017			longest = pag->pagf_flcount > 0;
1018
1019		if (pag->pagf_freeblks >= needspace + ineed &&
1020		    longest >= ineed) {
1021			xfs_perag_put(pag);
1022			return agno;
1023		}
1024nextag:
1025		xfs_perag_put(pag);
1026		/*
1027		 * No point in iterating over the rest, if we're shutting
1028		 * down.
1029		 */
1030		if (XFS_FORCED_SHUTDOWN(mp))
1031			return NULLAGNUMBER;
1032		agno++;
1033		if (agno >= agcount)
1034			agno = 0;
1035		if (agno == pagno) {
1036			if (flags == 0)
1037				return NULLAGNUMBER;
1038			flags = 0;
1039		}
1040	}
1041}
1042
1043/*
1044 * Try to retrieve the next record to the left/right from the current one.
1045 */
1046STATIC int
1047xfs_ialloc_next_rec(
1048	struct xfs_btree_cur	*cur,
1049	xfs_inobt_rec_incore_t	*rec,
1050	int			*done,
1051	int			left)
1052{
1053	int                     error;
1054	int			i;
1055
1056	if (left)
1057		error = xfs_btree_decrement(cur, 0, &i);
1058	else
1059		error = xfs_btree_increment(cur, 0, &i);
1060
1061	if (error)
1062		return error;
1063	*done = !i;
1064	if (i) {
1065		error = xfs_inobt_get_rec(cur, rec, &i);
1066		if (error)
1067			return error;
1068		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1069			return -EFSCORRUPTED;
1070	}
1071
1072	return 0;
1073}
1074
1075STATIC int
1076xfs_ialloc_get_rec(
1077	struct xfs_btree_cur	*cur,
1078	xfs_agino_t		agino,
1079	xfs_inobt_rec_incore_t	*rec,
1080	int			*done)
1081{
1082	int                     error;
1083	int			i;
1084
1085	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
1086	if (error)
1087		return error;
1088	*done = !i;
1089	if (i) {
1090		error = xfs_inobt_get_rec(cur, rec, &i);
1091		if (error)
1092			return error;
1093		if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1094			return -EFSCORRUPTED;
1095	}
1096
1097	return 0;
1098}
1099
1100/*
1101 * Return the offset of the first free inode in the record. If the inode chunk
1102 * is sparsely allocated, we convert the record holemask to inode granularity
1103 * and mask off the unallocated regions from the inode free mask.
1104 */
1105STATIC int
1106xfs_inobt_first_free_inode(
1107	struct xfs_inobt_rec_incore	*rec)
1108{
1109	xfs_inofree_t			realfree;
1110
1111	/* if there are no holes, return the first available offset */
1112	if (!xfs_inobt_issparse(rec->ir_holemask))
1113		return xfs_lowbit64(rec->ir_free);
1114
1115	realfree = xfs_inobt_irec_to_allocmask(rec);
1116	realfree &= rec->ir_free;
1117
1118	return xfs_lowbit64(realfree);
1119}
1120
1121/*
1122 * Allocate an inode using the inobt-only algorithm.
1123 */
1124STATIC int
1125xfs_dialloc_ag_inobt(
1126	struct xfs_trans	*tp,
1127	struct xfs_buf		*agbp,
 
1128	xfs_ino_t		parent,
1129	xfs_ino_t		*inop)
1130{
1131	struct xfs_mount	*mp = tp->t_mountp;
1132	struct xfs_agi		*agi = agbp->b_addr;
1133	xfs_agnumber_t		agno = be32_to_cpu(agi->agi_seqno);
1134	xfs_agnumber_t		pagno = XFS_INO_TO_AGNO(mp, parent);
1135	xfs_agino_t		pagino = XFS_INO_TO_AGINO(mp, parent);
1136	struct xfs_perag	*pag = agbp->b_pag;
1137	struct xfs_btree_cur	*cur, *tcur;
1138	struct xfs_inobt_rec_incore rec, trec;
1139	xfs_ino_t		ino;
1140	int			error;
1141	int			offset;
1142	int			i, j;
1143	int			searchdistance = 10;
1144
1145	ASSERT(pag->pagi_init);
1146	ASSERT(pag->pagi_inodeok);
1147	ASSERT(pag->pagi_freecount > 0);
1148
1149 restart_pagno:
1150	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
1151	/*
1152	 * If pagino is 0 (this is the root inode allocation) use newino.
1153	 * This must work because we've just allocated some.
1154	 */
1155	if (!pagino)
1156		pagino = be32_to_cpu(agi->agi_newino);
1157
1158	error = xfs_check_agi_freecount(cur, agi);
1159	if (error)
1160		goto error0;
1161
1162	/*
1163	 * If in the same AG as the parent, try to get near the parent.
1164	 */
1165	if (pagno == agno) {
1166		int		doneleft;	/* done, to the left */
1167		int		doneright;	/* done, to the right */
1168
1169		error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
1170		if (error)
1171			goto error0;
1172		if (XFS_IS_CORRUPT(mp, i != 1)) {
1173			error = -EFSCORRUPTED;
1174			goto error0;
1175		}
1176
1177		error = xfs_inobt_get_rec(cur, &rec, &j);
1178		if (error)
1179			goto error0;
1180		if (XFS_IS_CORRUPT(mp, j != 1)) {
1181			error = -EFSCORRUPTED;
1182			goto error0;
1183		}
1184
1185		if (rec.ir_freecount > 0) {
1186			/*
1187			 * Found a free inode in the same chunk
1188			 * as the parent, done.
1189			 */
1190			goto alloc_inode;
1191		}
1192
1193
1194		/*
1195		 * In the same AG as parent, but parent's chunk is full.
1196		 */
1197
1198		/* duplicate the cursor, search left & right simultaneously */
1199		error = xfs_btree_dup_cursor(cur, &tcur);
1200		if (error)
1201			goto error0;
1202
1203		/*
1204		 * Skip to last blocks looked up if same parent inode.
1205		 */
1206		if (pagino != NULLAGINO &&
1207		    pag->pagl_pagino == pagino &&
1208		    pag->pagl_leftrec != NULLAGINO &&
1209		    pag->pagl_rightrec != NULLAGINO) {
1210			error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
1211						   &trec, &doneleft);
1212			if (error)
1213				goto error1;
1214
1215			error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
1216						   &rec, &doneright);
1217			if (error)
1218				goto error1;
1219		} else {
1220			/* search left with tcur, back up 1 record */
1221			error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
1222			if (error)
1223				goto error1;
1224
1225			/* search right with cur, go forward 1 record. */
1226			error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
1227			if (error)
1228				goto error1;
1229		}
1230
1231		/*
1232		 * Loop until we find an inode chunk with a free inode.
1233		 */
1234		while (--searchdistance > 0 && (!doneleft || !doneright)) {
1235			int	useleft;  /* using left inode chunk this time */
1236
1237			/* figure out the closer block if both are valid. */
1238			if (!doneleft && !doneright) {
1239				useleft = pagino -
1240				 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
1241				  rec.ir_startino - pagino;
1242			} else {
1243				useleft = !doneleft;
1244			}
1245
1246			/* free inodes to the left? */
1247			if (useleft && trec.ir_freecount) {
1248				xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1249				cur = tcur;
1250
1251				pag->pagl_leftrec = trec.ir_startino;
1252				pag->pagl_rightrec = rec.ir_startino;
1253				pag->pagl_pagino = pagino;
1254				rec = trec;
1255				goto alloc_inode;
1256			}
1257
1258			/* free inodes to the right? */
1259			if (!useleft && rec.ir_freecount) {
1260				xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1261
1262				pag->pagl_leftrec = trec.ir_startino;
1263				pag->pagl_rightrec = rec.ir_startino;
1264				pag->pagl_pagino = pagino;
1265				goto alloc_inode;
1266			}
1267
1268			/* get next record to check */
1269			if (useleft) {
1270				error = xfs_ialloc_next_rec(tcur, &trec,
1271								 &doneleft, 1);
1272			} else {
1273				error = xfs_ialloc_next_rec(cur, &rec,
1274								 &doneright, 0);
1275			}
1276			if (error)
1277				goto error1;
1278		}
1279
1280		if (searchdistance <= 0) {
1281			/*
1282			 * Not in range - save last search
1283			 * location and allocate a new inode
1284			 */
1285			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1286			pag->pagl_leftrec = trec.ir_startino;
1287			pag->pagl_rightrec = rec.ir_startino;
1288			pag->pagl_pagino = pagino;
1289
1290		} else {
1291			/*
1292			 * We've reached the end of the btree. because
1293			 * we are only searching a small chunk of the
1294			 * btree each search, there is obviously free
1295			 * inodes closer to the parent inode than we
1296			 * are now. restart the search again.
1297			 */
1298			pag->pagl_pagino = NULLAGINO;
1299			pag->pagl_leftrec = NULLAGINO;
1300			pag->pagl_rightrec = NULLAGINO;
1301			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1302			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1303			goto restart_pagno;
1304		}
1305	}
1306
1307	/*
1308	 * In a different AG from the parent.
1309	 * See if the most recently allocated block has any free.
1310	 */
1311	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1312		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1313					 XFS_LOOKUP_EQ, &i);
1314		if (error)
1315			goto error0;
1316
1317		if (i == 1) {
1318			error = xfs_inobt_get_rec(cur, &rec, &j);
1319			if (error)
1320				goto error0;
1321
1322			if (j == 1 && rec.ir_freecount > 0) {
1323				/*
1324				 * The last chunk allocated in the group
1325				 * still has a free inode.
1326				 */
1327				goto alloc_inode;
1328			}
1329		}
1330	}
1331
1332	/*
1333	 * None left in the last group, search the whole AG
1334	 */
1335	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1336	if (error)
1337		goto error0;
1338	if (XFS_IS_CORRUPT(mp, i != 1)) {
1339		error = -EFSCORRUPTED;
1340		goto error0;
1341	}
1342
1343	for (;;) {
1344		error = xfs_inobt_get_rec(cur, &rec, &i);
1345		if (error)
1346			goto error0;
1347		if (XFS_IS_CORRUPT(mp, i != 1)) {
1348			error = -EFSCORRUPTED;
1349			goto error0;
1350		}
1351		if (rec.ir_freecount > 0)
1352			break;
1353		error = xfs_btree_increment(cur, 0, &i);
1354		if (error)
1355			goto error0;
1356		if (XFS_IS_CORRUPT(mp, i != 1)) {
1357			error = -EFSCORRUPTED;
1358			goto error0;
1359		}
1360	}
1361
1362alloc_inode:
1363	offset = xfs_inobt_first_free_inode(&rec);
1364	ASSERT(offset >= 0);
1365	ASSERT(offset < XFS_INODES_PER_CHUNK);
1366	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1367				   XFS_INODES_PER_CHUNK) == 0);
1368	ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
1369	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1370	rec.ir_freecount--;
1371	error = xfs_inobt_update(cur, &rec);
1372	if (error)
1373		goto error0;
1374	be32_add_cpu(&agi->agi_freecount, -1);
1375	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1376	pag->pagi_freecount--;
1377
1378	error = xfs_check_agi_freecount(cur, agi);
1379	if (error)
1380		goto error0;
1381
1382	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1383	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1384	*inop = ino;
1385	return 0;
1386error1:
1387	xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1388error0:
1389	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1390	return error;
1391}
1392
1393/*
1394 * Use the free inode btree to allocate an inode based on distance from the
1395 * parent. Note that the provided cursor may be deleted and replaced.
1396 */
1397STATIC int
1398xfs_dialloc_ag_finobt_near(
1399	xfs_agino_t			pagino,
1400	struct xfs_btree_cur		**ocur,
1401	struct xfs_inobt_rec_incore	*rec)
1402{
1403	struct xfs_btree_cur		*lcur = *ocur;	/* left search cursor */
1404	struct xfs_btree_cur		*rcur;	/* right search cursor */
1405	struct xfs_inobt_rec_incore	rrec;
1406	int				error;
1407	int				i, j;
1408
1409	error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
1410	if (error)
1411		return error;
1412
1413	if (i == 1) {
1414		error = xfs_inobt_get_rec(lcur, rec, &i);
1415		if (error)
1416			return error;
1417		if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1))
1418			return -EFSCORRUPTED;
1419
1420		/*
1421		 * See if we've landed in the parent inode record. The finobt
1422		 * only tracks chunks with at least one free inode, so record
1423		 * existence is enough.
1424		 */
1425		if (pagino >= rec->ir_startino &&
1426		    pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
1427			return 0;
1428	}
1429
1430	error = xfs_btree_dup_cursor(lcur, &rcur);
1431	if (error)
1432		return error;
1433
1434	error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
1435	if (error)
1436		goto error_rcur;
1437	if (j == 1) {
1438		error = xfs_inobt_get_rec(rcur, &rrec, &j);
1439		if (error)
1440			goto error_rcur;
1441		if (XFS_IS_CORRUPT(lcur->bc_mp, j != 1)) {
1442			error = -EFSCORRUPTED;
1443			goto error_rcur;
1444		}
1445	}
1446
1447	if (XFS_IS_CORRUPT(lcur->bc_mp, i != 1 && j != 1)) {
1448		error = -EFSCORRUPTED;
1449		goto error_rcur;
1450	}
1451	if (i == 1 && j == 1) {
1452		/*
1453		 * Both the left and right records are valid. Choose the closer
1454		 * inode chunk to the target.
1455		 */
1456		if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
1457		    (rrec.ir_startino - pagino)) {
1458			*rec = rrec;
1459			xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1460			*ocur = rcur;
1461		} else {
1462			xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1463		}
1464	} else if (j == 1) {
1465		/* only the right record is valid */
1466		*rec = rrec;
1467		xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1468		*ocur = rcur;
1469	} else if (i == 1) {
1470		/* only the left record is valid */
1471		xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1472	}
1473
1474	return 0;
1475
1476error_rcur:
1477	xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
1478	return error;
1479}
1480
1481/*
1482 * Use the free inode btree to find a free inode based on a newino hint. If
1483 * the hint is NULL, find the first free inode in the AG.
1484 */
1485STATIC int
1486xfs_dialloc_ag_finobt_newino(
1487	struct xfs_agi			*agi,
1488	struct xfs_btree_cur		*cur,
1489	struct xfs_inobt_rec_incore	*rec)
1490{
1491	int error;
1492	int i;
1493
1494	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1495		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1496					 XFS_LOOKUP_EQ, &i);
1497		if (error)
1498			return error;
1499		if (i == 1) {
1500			error = xfs_inobt_get_rec(cur, rec, &i);
1501			if (error)
1502				return error;
1503			if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1504				return -EFSCORRUPTED;
1505			return 0;
1506		}
1507	}
1508
1509	/*
1510	 * Find the first inode available in the AG.
1511	 */
1512	error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1513	if (error)
1514		return error;
1515	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1516		return -EFSCORRUPTED;
1517
1518	error = xfs_inobt_get_rec(cur, rec, &i);
1519	if (error)
1520		return error;
1521	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1522		return -EFSCORRUPTED;
1523
1524	return 0;
1525}
1526
1527/*
1528 * Update the inobt based on a modification made to the finobt. Also ensure that
1529 * the records from both trees are equivalent post-modification.
1530 */
1531STATIC int
1532xfs_dialloc_ag_update_inobt(
1533	struct xfs_btree_cur		*cur,	/* inobt cursor */
1534	struct xfs_inobt_rec_incore	*frec,	/* finobt record */
1535	int				offset) /* inode offset */
1536{
1537	struct xfs_inobt_rec_incore	rec;
1538	int				error;
1539	int				i;
1540
1541	error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
1542	if (error)
1543		return error;
1544	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1545		return -EFSCORRUPTED;
1546
1547	error = xfs_inobt_get_rec(cur, &rec, &i);
1548	if (error)
1549		return error;
1550	if (XFS_IS_CORRUPT(cur->bc_mp, i != 1))
1551		return -EFSCORRUPTED;
1552	ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
1553				   XFS_INODES_PER_CHUNK) == 0);
1554
1555	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1556	rec.ir_freecount--;
1557
1558	if (XFS_IS_CORRUPT(cur->bc_mp,
1559			   rec.ir_free != frec->ir_free ||
1560			   rec.ir_freecount != frec->ir_freecount))
1561		return -EFSCORRUPTED;
1562
1563	return xfs_inobt_update(cur, &rec);
1564}
1565
1566/*
1567 * Allocate an inode using the free inode btree, if available. Otherwise, fall
1568 * back to the inobt search algorithm.
1569 *
1570 * The caller selected an AG for us, and made sure that free inodes are
1571 * available.
1572 */
1573STATIC int
1574xfs_dialloc_ag(
1575	struct xfs_trans	*tp,
1576	struct xfs_buf		*agbp,
 
1577	xfs_ino_t		parent,
1578	xfs_ino_t		*inop)
1579{
1580	struct xfs_mount		*mp = tp->t_mountp;
1581	struct xfs_agi			*agi = agbp->b_addr;
1582	xfs_agnumber_t			agno = be32_to_cpu(agi->agi_seqno);
1583	xfs_agnumber_t			pagno = XFS_INO_TO_AGNO(mp, parent);
1584	xfs_agino_t			pagino = XFS_INO_TO_AGINO(mp, parent);
1585	struct xfs_btree_cur		*cur;	/* finobt cursor */
1586	struct xfs_btree_cur		*icur;	/* inobt cursor */
1587	struct xfs_inobt_rec_incore	rec;
1588	xfs_ino_t			ino;
1589	int				error;
1590	int				offset;
1591	int				i;
1592
1593	if (!xfs_sb_version_hasfinobt(&mp->m_sb))
1594		return xfs_dialloc_ag_inobt(tp, agbp, parent, inop);
1595
1596	/*
1597	 * If pagino is 0 (this is the root inode allocation) use newino.
1598	 * This must work because we've just allocated some.
1599	 */
1600	if (!pagino)
1601		pagino = be32_to_cpu(agi->agi_newino);
1602
1603	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_FINO);
1604
1605	error = xfs_check_agi_freecount(cur, agi);
1606	if (error)
1607		goto error_cur;
1608
1609	/*
1610	 * The search algorithm depends on whether we're in the same AG as the
1611	 * parent. If so, find the closest available inode to the parent. If
1612	 * not, consider the agi hint or find the first free inode in the AG.
1613	 */
1614	if (agno == pagno)
1615		error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
1616	else
1617		error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
1618	if (error)
1619		goto error_cur;
1620
1621	offset = xfs_inobt_first_free_inode(&rec);
1622	ASSERT(offset >= 0);
1623	ASSERT(offset < XFS_INODES_PER_CHUNK);
1624	ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1625				   XFS_INODES_PER_CHUNK) == 0);
1626	ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
1627
1628	/*
1629	 * Modify or remove the finobt record.
1630	 */
1631	rec.ir_free &= ~XFS_INOBT_MASK(offset);
1632	rec.ir_freecount--;
1633	if (rec.ir_freecount)
1634		error = xfs_inobt_update(cur, &rec);
1635	else
1636		error = xfs_btree_delete(cur, &i);
1637	if (error)
1638		goto error_cur;
1639
1640	/*
1641	 * The finobt has now been updated appropriately. We haven't updated the
1642	 * agi and superblock yet, so we can create an inobt cursor and validate
1643	 * the original freecount. If all is well, make the equivalent update to
1644	 * the inobt using the finobt record and offset information.
1645	 */
1646	icur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
1647
1648	error = xfs_check_agi_freecount(icur, agi);
1649	if (error)
1650		goto error_icur;
1651
1652	error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
1653	if (error)
1654		goto error_icur;
1655
1656	/*
1657	 * Both trees have now been updated. We must update the perag and
1658	 * superblock before we can check the freecount for each btree.
1659	 */
1660	be32_add_cpu(&agi->agi_freecount, -1);
1661	xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1662	agbp->b_pag->pagi_freecount--;
1663
1664	xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1665
1666	error = xfs_check_agi_freecount(icur, agi);
1667	if (error)
1668		goto error_icur;
1669	error = xfs_check_agi_freecount(cur, agi);
1670	if (error)
1671		goto error_icur;
1672
1673	xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
1674	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1675	*inop = ino;
1676	return 0;
1677
1678error_icur:
1679	xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
1680error_cur:
1681	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1682	return error;
1683}
1684
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1685/*
1686 * Allocate an inode on disk.
1687 *
1688 * Mode is used to tell whether the new inode will need space, and whether it
1689 * is a directory.
1690 *
1691 * This function is designed to be called twice if it has to do an allocation
1692 * to make more free inodes.  On the first call, *IO_agbp should be set to NULL.
1693 * If an inode is available without having to performn an allocation, an inode
1694 * number is returned.  In this case, *IO_agbp is set to NULL.  If an allocation
1695 * needs to be done, xfs_dialloc returns the current AGI buffer in *IO_agbp.
1696 * The caller should then commit the current transaction, allocate a
1697 * new transaction, and call xfs_dialloc() again, passing in the previous value
1698 * of *IO_agbp.  IO_agbp should be held across the transactions. Since the AGI
1699 * buffer is locked across the two calls, the second call is guaranteed to have
1700 * a free inode available.
1701 *
1702 * Once we successfully pick an inode its number is returned and the on-disk
1703 * data structures are updated.  The inode itself is not read in, since doing so
1704 * would break ordering constraints with xfs_reclaim.
 
1705 */
1706int
1707xfs_dialloc(
1708	struct xfs_trans	*tp,
1709	xfs_ino_t		parent,
1710	umode_t			mode,
1711	struct xfs_buf		**IO_agbp,
1712	xfs_ino_t		*inop)
1713{
1714	struct xfs_mount	*mp = tp->t_mountp;
1715	struct xfs_buf		*agbp;
1716	xfs_agnumber_t		agno;
1717	int			error;
1718	int			ialloced;
1719	int			noroom = 0;
1720	xfs_agnumber_t		start_agno;
1721	struct xfs_perag	*pag;
1722	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
1723	int			okalloc = 1;
1724
1725	if (*IO_agbp) {
1726		/*
1727		 * If the caller passes in a pointer to the AGI buffer,
1728		 * continue where we left off before.  In this case, we
1729		 * know that the allocation group has free inodes.
1730		 */
1731		agbp = *IO_agbp;
1732		goto out_alloc;
1733	}
1734
1735	/*
1736	 * We do not have an agbp, so select an initial allocation
1737	 * group for inode allocation.
 
1738	 */
1739	start_agno = xfs_ialloc_ag_select(tp, parent, mode);
1740	if (start_agno == NULLAGNUMBER) {
1741		*inop = NULLFSINO;
1742		return 0;
 
 
1743	}
1744
1745	/*
1746	 * If we have already hit the ceiling of inode blocks then clear
1747	 * okalloc so we scan all available agi structures for a free
1748	 * inode.
1749	 *
1750	 * Read rough value of mp->m_icount by percpu_counter_read_positive,
1751	 * which will sacrifice the preciseness but improve the performance.
1752	 */
1753	if (igeo->maxicount &&
1754	    percpu_counter_read_positive(&mp->m_icount) + igeo->ialloc_inos
1755							> igeo->maxicount) {
1756		noroom = 1;
1757		okalloc = 0;
1758	}
1759
1760	/*
1761	 * Loop until we find an allocation group that either has free inodes
1762	 * or in which we can allocate some inodes.  Iterate through the
1763	 * allocation groups upward, wrapping at the end.
1764	 */
1765	agno = start_agno;
 
1766	for (;;) {
1767		pag = xfs_perag_get(mp, agno);
1768		if (!pag->pagi_inodeok) {
1769			xfs_ialloc_next_ag(mp);
1770			goto nextag;
 
 
1771		}
1772
1773		if (!pag->pagi_init) {
1774			error = xfs_ialloc_pagi_init(mp, tp, agno);
1775			if (error)
1776				goto out_error;
1777		}
1778
1779		/*
1780		 * Do a first racy fast path check if this AG is usable.
1781		 */
1782		if (!pag->pagi_freecount && !okalloc)
1783			goto nextag;
1784
1785		/*
1786		 * Then read in the AGI buffer and recheck with the AGI buffer
1787		 * lock held.
1788		 */
1789		error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1790		if (error)
1791			goto out_error;
1792
1793		if (pag->pagi_freecount) {
1794			xfs_perag_put(pag);
1795			goto out_alloc;
1796		}
1797
1798		if (!okalloc)
1799			goto nextag_relse_buffer;
1800
1801
1802		error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced);
1803		if (error) {
1804			xfs_trans_brelse(tp, agbp);
1805
1806			if (error != -ENOSPC)
1807				goto out_error;
1808
1809			xfs_perag_put(pag);
1810			*inop = NULLFSINO;
1811			return 0;
1812		}
1813
1814		if (ialloced) {
1815			/*
1816			 * We successfully allocated some inodes, return
1817			 * the current context to the caller so that it
1818			 * can commit the current transaction and call
1819			 * us again where we left off.
1820			 */
1821			ASSERT(pag->pagi_freecount > 0);
1822			xfs_perag_put(pag);
1823
1824			*IO_agbp = agbp;
1825			*inop = NULLFSINO;
1826			return 0;
1827		}
1828
1829nextag_relse_buffer:
1830		xfs_trans_brelse(tp, agbp);
1831nextag:
1832		xfs_perag_put(pag);
1833		if (++agno == mp->m_sb.sb_agcount)
1834			agno = 0;
1835		if (agno == start_agno) {
1836			*inop = NULLFSINO;
1837			return noroom ? -ENOSPC : 0;
 
 
 
1838		}
 
1839	}
1840
1841out_alloc:
1842	*IO_agbp = NULL;
1843	return xfs_dialloc_ag(tp, agbp, parent, inop);
1844out_error:
1845	xfs_perag_put(pag);
1846	return error;
1847}
1848
1849/*
1850 * Free the blocks of an inode chunk. We must consider that the inode chunk
1851 * might be sparse and only free the regions that are allocated as part of the
1852 * chunk.
1853 */
1854STATIC void
1855xfs_difree_inode_chunk(
1856	struct xfs_trans		*tp,
1857	xfs_agnumber_t			agno,
1858	struct xfs_inobt_rec_incore	*rec)
1859{
1860	struct xfs_mount		*mp = tp->t_mountp;
1861	xfs_agblock_t			sagbno = XFS_AGINO_TO_AGBNO(mp,
1862							rec->ir_startino);
1863	int				startidx, endidx;
1864	int				nextbit;
1865	xfs_agblock_t			agbno;
1866	int				contigblk;
1867	DECLARE_BITMAP(holemask, XFS_INOBT_HOLEMASK_BITS);
1868
1869	if (!xfs_inobt_issparse(rec->ir_holemask)) {
1870		/* not sparse, calculate extent info directly */
1871		xfs_bmap_add_free(tp, XFS_AGB_TO_FSB(mp, agno, sagbno),
1872				  M_IGEO(mp)->ialloc_blks,
1873				  &XFS_RMAP_OINFO_INODES);
1874		return;
1875	}
1876
1877	/* holemask is only 16-bits (fits in an unsigned long) */
1878	ASSERT(sizeof(rec->ir_holemask) <= sizeof(holemask[0]));
1879	holemask[0] = rec->ir_holemask;
1880
1881	/*
1882	 * Find contiguous ranges of zeroes (i.e., allocated regions) in the
1883	 * holemask and convert the start/end index of each range to an extent.
1884	 * We start with the start and end index both pointing at the first 0 in
1885	 * the mask.
1886	 */
1887	startidx = endidx = find_first_zero_bit(holemask,
1888						XFS_INOBT_HOLEMASK_BITS);
1889	nextbit = startidx + 1;
1890	while (startidx < XFS_INOBT_HOLEMASK_BITS) {
1891		nextbit = find_next_zero_bit(holemask, XFS_INOBT_HOLEMASK_BITS,
1892					     nextbit);
1893		/*
1894		 * If the next zero bit is contiguous, update the end index of
1895		 * the current range and continue.
1896		 */
1897		if (nextbit != XFS_INOBT_HOLEMASK_BITS &&
1898		    nextbit == endidx + 1) {
1899			endidx = nextbit;
1900			goto next;
1901		}
1902
1903		/*
1904		 * nextbit is not contiguous with the current end index. Convert
1905		 * the current start/end to an extent and add it to the free
1906		 * list.
1907		 */
1908		agbno = sagbno + (startidx * XFS_INODES_PER_HOLEMASK_BIT) /
1909				  mp->m_sb.sb_inopblock;
1910		contigblk = ((endidx - startidx + 1) *
1911			     XFS_INODES_PER_HOLEMASK_BIT) /
1912			    mp->m_sb.sb_inopblock;
1913
1914		ASSERT(agbno % mp->m_sb.sb_spino_align == 0);
1915		ASSERT(contigblk % mp->m_sb.sb_spino_align == 0);
1916		xfs_bmap_add_free(tp, XFS_AGB_TO_FSB(mp, agno, agbno),
1917				  contigblk, &XFS_RMAP_OINFO_INODES);
1918
1919		/* reset range to current bit and carry on... */
1920		startidx = endidx = nextbit;
1921
1922next:
1923		nextbit++;
1924	}
1925}
1926
1927STATIC int
1928xfs_difree_inobt(
1929	struct xfs_mount		*mp,
1930	struct xfs_trans		*tp,
1931	struct xfs_buf			*agbp,
 
1932	xfs_agino_t			agino,
1933	struct xfs_icluster		*xic,
1934	struct xfs_inobt_rec_incore	*orec)
1935{
1936	struct xfs_agi			*agi = agbp->b_addr;
1937	xfs_agnumber_t			agno = be32_to_cpu(agi->agi_seqno);
1938	struct xfs_btree_cur		*cur;
1939	struct xfs_inobt_rec_incore	rec;
1940	int				ilen;
1941	int				error;
1942	int				i;
1943	int				off;
1944
1945	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1946	ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
1947
1948	/*
1949	 * Initialize the cursor.
1950	 */
1951	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
1952
1953	error = xfs_check_agi_freecount(cur, agi);
1954	if (error)
1955		goto error0;
1956
1957	/*
1958	 * Look for the entry describing this inode.
1959	 */
1960	if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1961		xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1962			__func__, error);
1963		goto error0;
1964	}
1965	if (XFS_IS_CORRUPT(mp, i != 1)) {
1966		error = -EFSCORRUPTED;
1967		goto error0;
1968	}
1969	error = xfs_inobt_get_rec(cur, &rec, &i);
1970	if (error) {
1971		xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1972			__func__, error);
1973		goto error0;
1974	}
1975	if (XFS_IS_CORRUPT(mp, i != 1)) {
1976		error = -EFSCORRUPTED;
1977		goto error0;
1978	}
1979	/*
1980	 * Get the offset in the inode chunk.
1981	 */
1982	off = agino - rec.ir_startino;
1983	ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1984	ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1985	/*
1986	 * Mark the inode free & increment the count.
1987	 */
1988	rec.ir_free |= XFS_INOBT_MASK(off);
1989	rec.ir_freecount++;
1990
1991	/*
1992	 * When an inode chunk is free, it becomes eligible for removal. Don't
1993	 * remove the chunk if the block size is large enough for multiple inode
1994	 * chunks (that might not be free).
1995	 */
1996	if (!(mp->m_flags & XFS_MOUNT_IKEEP) &&
1997	    rec.ir_free == XFS_INOBT_ALL_FREE &&
1998	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
1999		struct xfs_perag	*pag = agbp->b_pag;
2000
2001		xic->deleted = true;
2002		xic->first_ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino);
 
2003		xic->alloc = xfs_inobt_irec_to_allocmask(&rec);
2004
2005		/*
2006		 * Remove the inode cluster from the AGI B+Tree, adjust the
2007		 * AGI and Superblock inode counts, and mark the disk space
2008		 * to be freed when the transaction is committed.
2009		 */
2010		ilen = rec.ir_freecount;
2011		be32_add_cpu(&agi->agi_count, -ilen);
2012		be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
2013		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
2014		pag->pagi_freecount -= ilen - 1;
2015		pag->pagi_count -= ilen;
2016		xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
2017		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
2018
2019		if ((error = xfs_btree_delete(cur, &i))) {
2020			xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
2021				__func__, error);
2022			goto error0;
2023		}
2024
2025		xfs_difree_inode_chunk(tp, agno, &rec);
2026	} else {
2027		xic->deleted = false;
2028
2029		error = xfs_inobt_update(cur, &rec);
2030		if (error) {
2031			xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
2032				__func__, error);
2033			goto error0;
2034		}
2035
2036		/* 
2037		 * Change the inode free counts and log the ag/sb changes.
2038		 */
2039		be32_add_cpu(&agi->agi_freecount, 1);
2040		xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
2041		agbp->b_pag->pagi_freecount++;
2042		xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
2043	}
2044
2045	error = xfs_check_agi_freecount(cur, agi);
2046	if (error)
2047		goto error0;
2048
2049	*orec = rec;
2050	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2051	return 0;
2052
2053error0:
2054	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2055	return error;
2056}
2057
2058/*
2059 * Free an inode in the free inode btree.
2060 */
2061STATIC int
2062xfs_difree_finobt(
2063	struct xfs_mount		*mp,
2064	struct xfs_trans		*tp,
2065	struct xfs_buf			*agbp,
 
2066	xfs_agino_t			agino,
2067	struct xfs_inobt_rec_incore	*ibtrec) /* inobt record */
2068{
2069	struct xfs_agi			*agi = agbp->b_addr;
2070	xfs_agnumber_t			agno = be32_to_cpu(agi->agi_seqno);
2071	struct xfs_btree_cur		*cur;
2072	struct xfs_inobt_rec_incore	rec;
2073	int				offset = agino - ibtrec->ir_startino;
2074	int				error;
2075	int				i;
2076
2077	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_FINO);
2078
2079	error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
2080	if (error)
2081		goto error;
2082	if (i == 0) {
2083		/*
2084		 * If the record does not exist in the finobt, we must have just
2085		 * freed an inode in a previously fully allocated chunk. If not,
2086		 * something is out of sync.
2087		 */
2088		if (XFS_IS_CORRUPT(mp, ibtrec->ir_freecount != 1)) {
2089			error = -EFSCORRUPTED;
2090			goto error;
2091		}
2092
2093		error = xfs_inobt_insert_rec(cur, ibtrec->ir_holemask,
2094					     ibtrec->ir_count,
2095					     ibtrec->ir_freecount,
2096					     ibtrec->ir_free, &i);
2097		if (error)
2098			goto error;
2099		ASSERT(i == 1);
2100
2101		goto out;
2102	}
2103
2104	/*
2105	 * Read and update the existing record. We could just copy the ibtrec
2106	 * across here, but that would defeat the purpose of having redundant
2107	 * metadata. By making the modifications independently, we can catch
2108	 * corruptions that we wouldn't see if we just copied from one record
2109	 * to another.
2110	 */
2111	error = xfs_inobt_get_rec(cur, &rec, &i);
2112	if (error)
2113		goto error;
2114	if (XFS_IS_CORRUPT(mp, i != 1)) {
2115		error = -EFSCORRUPTED;
2116		goto error;
2117	}
2118
2119	rec.ir_free |= XFS_INOBT_MASK(offset);
2120	rec.ir_freecount++;
2121
2122	if (XFS_IS_CORRUPT(mp,
2123			   rec.ir_free != ibtrec->ir_free ||
2124			   rec.ir_freecount != ibtrec->ir_freecount)) {
2125		error = -EFSCORRUPTED;
2126		goto error;
2127	}
2128
2129	/*
2130	 * The content of inobt records should always match between the inobt
2131	 * and finobt. The lifecycle of records in the finobt is different from
2132	 * the inobt in that the finobt only tracks records with at least one
2133	 * free inode. Hence, if all of the inodes are free and we aren't
2134	 * keeping inode chunks permanently on disk, remove the record.
2135	 * Otherwise, update the record with the new information.
2136	 *
2137	 * Note that we currently can't free chunks when the block size is large
2138	 * enough for multiple chunks. Leave the finobt record to remain in sync
2139	 * with the inobt.
2140	 */
2141	if (rec.ir_free == XFS_INOBT_ALL_FREE &&
2142	    mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK &&
2143	    !(mp->m_flags & XFS_MOUNT_IKEEP)) {
2144		error = xfs_btree_delete(cur, &i);
2145		if (error)
2146			goto error;
2147		ASSERT(i == 1);
2148	} else {
2149		error = xfs_inobt_update(cur, &rec);
2150		if (error)
2151			goto error;
2152	}
2153
2154out:
2155	error = xfs_check_agi_freecount(cur, agi);
2156	if (error)
2157		goto error;
2158
2159	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2160	return 0;
2161
2162error:
2163	xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2164	return error;
2165}
2166
2167/*
2168 * Free disk inode.  Carefully avoids touching the incore inode, all
2169 * manipulations incore are the caller's responsibility.
2170 * The on-disk inode is not changed by this operation, only the
2171 * btree (free inode mask) is changed.
2172 */
2173int
2174xfs_difree(
2175	struct xfs_trans	*tp,		/* transaction pointer */
2176	xfs_ino_t		inode,		/* inode to be freed */
2177	struct xfs_icluster	*xic)	/* cluster info if deleted */
 
2178{
2179	/* REFERENCED */
2180	xfs_agblock_t		agbno;	/* block number containing inode */
2181	struct xfs_buf		*agbp;	/* buffer for allocation group header */
2182	xfs_agino_t		agino;	/* allocation group inode number */
2183	xfs_agnumber_t		agno;	/* allocation group number */
2184	int			error;	/* error return value */
2185	struct xfs_mount	*mp;	/* mount structure for filesystem */
2186	struct xfs_inobt_rec_incore rec;/* btree record */
2187
2188	mp = tp->t_mountp;
2189
2190	/*
2191	 * Break up inode number into its components.
2192	 */
2193	agno = XFS_INO_TO_AGNO(mp, inode);
2194	if (agno >= mp->m_sb.sb_agcount)  {
2195		xfs_warn(mp, "%s: agno >= mp->m_sb.sb_agcount (%d >= %d).",
2196			__func__, agno, mp->m_sb.sb_agcount);
2197		ASSERT(0);
2198		return -EINVAL;
2199	}
2200	agino = XFS_INO_TO_AGINO(mp, inode);
2201	if (inode != XFS_AGINO_TO_INO(mp, agno, agino))  {
2202		xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
2203			__func__, (unsigned long long)inode,
2204			(unsigned long long)XFS_AGINO_TO_INO(mp, agno, agino));
2205		ASSERT(0);
2206		return -EINVAL;
2207	}
2208	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2209	if (agbno >= mp->m_sb.sb_agblocks)  {
2210		xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
2211			__func__, agbno, mp->m_sb.sb_agblocks);
2212		ASSERT(0);
2213		return -EINVAL;
2214	}
2215	/*
2216	 * Get the allocation group header.
2217	 */
2218	error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
2219	if (error) {
2220		xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
2221			__func__, error);
2222		return error;
2223	}
2224
2225	/*
2226	 * Fix up the inode allocation btree.
2227	 */
2228	error = xfs_difree_inobt(mp, tp, agbp, agino, xic, &rec);
2229	if (error)
2230		goto error0;
2231
2232	/*
2233	 * Fix up the free inode btree.
2234	 */
2235	if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
2236		error = xfs_difree_finobt(mp, tp, agbp, agino, &rec);
2237		if (error)
2238			goto error0;
2239	}
2240
2241	return 0;
2242
2243error0:
2244	return error;
2245}
2246
2247STATIC int
2248xfs_imap_lookup(
2249	struct xfs_mount	*mp,
2250	struct xfs_trans	*tp,
2251	xfs_agnumber_t		agno,
2252	xfs_agino_t		agino,
2253	xfs_agblock_t		agbno,
2254	xfs_agblock_t		*chunk_agbno,
2255	xfs_agblock_t		*offset_agbno,
2256	int			flags)
2257{
2258	struct xfs_inobt_rec_incore rec;
2259	struct xfs_btree_cur	*cur;
2260	struct xfs_buf		*agbp;
2261	int			error;
2262	int			i;
2263
2264	error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
2265	if (error) {
2266		xfs_alert(mp,
2267			"%s: xfs_ialloc_read_agi() returned error %d, agno %d",
2268			__func__, error, agno);
2269		return error;
2270	}
2271
2272	/*
2273	 * Lookup the inode record for the given agino. If the record cannot be
2274	 * found, then it's an invalid inode number and we should abort. Once
2275	 * we have a record, we need to ensure it contains the inode number
2276	 * we are looking up.
2277	 */
2278	cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
2279	error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
2280	if (!error) {
2281		if (i)
2282			error = xfs_inobt_get_rec(cur, &rec, &i);
2283		if (!error && i == 0)
2284			error = -EINVAL;
2285	}
2286
2287	xfs_trans_brelse(tp, agbp);
2288	xfs_btree_del_cursor(cur, error);
2289	if (error)
2290		return error;
2291
2292	/* check that the returned record contains the required inode */
2293	if (rec.ir_startino > agino ||
2294	    rec.ir_startino + M_IGEO(mp)->ialloc_inos <= agino)
2295		return -EINVAL;
2296
2297	/* for untrusted inodes check it is allocated first */
2298	if ((flags & XFS_IGET_UNTRUSTED) &&
2299	    (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
2300		return -EINVAL;
2301
2302	*chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
2303	*offset_agbno = agbno - *chunk_agbno;
2304	return 0;
2305}
2306
2307/*
2308 * Return the location of the inode in imap, for mapping it into a buffer.
2309 */
2310int
2311xfs_imap(
2312	xfs_mount_t	 *mp,	/* file system mount structure */
2313	xfs_trans_t	 *tp,	/* transaction pointer */
2314	xfs_ino_t	ino,	/* inode to locate */
2315	struct xfs_imap	*imap,	/* location map structure */
2316	uint		flags)	/* flags for inode btree lookup */
2317{
2318	xfs_agblock_t	agbno;	/* block number of inode in the alloc group */
2319	xfs_agino_t	agino;	/* inode number within alloc group */
2320	xfs_agnumber_t	agno;	/* allocation group number */
2321	xfs_agblock_t	chunk_agbno;	/* first block in inode chunk */
2322	xfs_agblock_t	cluster_agbno;	/* first block in inode cluster */
2323	int		error;	/* error code */
2324	int		offset;	/* index of inode in its buffer */
2325	xfs_agblock_t	offset_agbno;	/* blks from chunk start to inode */
2326
2327	ASSERT(ino != NULLFSINO);
2328
2329	/*
2330	 * Split up the inode number into its parts.
2331	 */
2332	agno = XFS_INO_TO_AGNO(mp, ino);
2333	agino = XFS_INO_TO_AGINO(mp, ino);
2334	agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2335	if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks ||
2336	    ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
 
2337#ifdef DEBUG
2338		/*
2339		 * Don't output diagnostic information for untrusted inodes
2340		 * as they can be invalid without implying corruption.
2341		 */
2342		if (flags & XFS_IGET_UNTRUSTED)
2343			return -EINVAL;
2344		if (agno >= mp->m_sb.sb_agcount) {
2345			xfs_alert(mp,
2346				"%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
2347				__func__, agno, mp->m_sb.sb_agcount);
 
2348		}
2349		if (agbno >= mp->m_sb.sb_agblocks) {
2350			xfs_alert(mp,
2351		"%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
2352				__func__, (unsigned long long)agbno,
2353				(unsigned long)mp->m_sb.sb_agblocks);
2354		}
2355		if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
2356			xfs_alert(mp,
2357		"%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
2358				__func__, ino,
2359				XFS_AGINO_TO_INO(mp, agno, agino));
2360		}
2361		xfs_stack_trace();
2362#endif /* DEBUG */
2363		return -EINVAL;
2364	}
2365
2366	/*
2367	 * For bulkstat and handle lookups, we have an untrusted inode number
2368	 * that we have to verify is valid. We cannot do this just by reading
2369	 * the inode buffer as it may have been unlinked and removed leaving
2370	 * inodes in stale state on disk. Hence we have to do a btree lookup
2371	 * in all cases where an untrusted inode number is passed.
2372	 */
2373	if (flags & XFS_IGET_UNTRUSTED) {
2374		error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
2375					&chunk_agbno, &offset_agbno, flags);
2376		if (error)
2377			return error;
2378		goto out_map;
2379	}
2380
2381	/*
2382	 * If the inode cluster size is the same as the blocksize or
2383	 * smaller we get to the buffer by simple arithmetics.
2384	 */
2385	if (M_IGEO(mp)->blocks_per_cluster == 1) {
2386		offset = XFS_INO_TO_OFFSET(mp, ino);
2387		ASSERT(offset < mp->m_sb.sb_inopblock);
2388
2389		imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
2390		imap->im_len = XFS_FSB_TO_BB(mp, 1);
2391		imap->im_boffset = (unsigned short)(offset <<
2392							mp->m_sb.sb_inodelog);
2393		return 0;
 
2394	}
2395
2396	/*
2397	 * If the inode chunks are aligned then use simple maths to
2398	 * find the location. Otherwise we have to do a btree
2399	 * lookup to find the location.
2400	 */
2401	if (M_IGEO(mp)->inoalign_mask) {
2402		offset_agbno = agbno & M_IGEO(mp)->inoalign_mask;
2403		chunk_agbno = agbno - offset_agbno;
2404	} else {
2405		error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
2406					&chunk_agbno, &offset_agbno, flags);
2407		if (error)
2408			return error;
2409	}
2410
2411out_map:
2412	ASSERT(agbno >= chunk_agbno);
2413	cluster_agbno = chunk_agbno +
2414		((offset_agbno / M_IGEO(mp)->blocks_per_cluster) *
2415		 M_IGEO(mp)->blocks_per_cluster);
2416	offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
2417		XFS_INO_TO_OFFSET(mp, ino);
2418
2419	imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno);
2420	imap->im_len = XFS_FSB_TO_BB(mp, M_IGEO(mp)->blocks_per_cluster);
2421	imap->im_boffset = (unsigned short)(offset << mp->m_sb.sb_inodelog);
2422
2423	/*
2424	 * If the inode number maps to a block outside the bounds
2425	 * of the file system then return NULL rather than calling
2426	 * read_buf and panicing when we get an error from the
2427	 * driver.
2428	 */
2429	if ((imap->im_blkno + imap->im_len) >
2430	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
2431		xfs_alert(mp,
2432	"%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
2433			__func__, (unsigned long long) imap->im_blkno,
2434			(unsigned long long) imap->im_len,
2435			XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
2436		return -EINVAL;
 
2437	}
2438	return 0;
 
 
 
 
2439}
2440
2441/*
2442 * Log specified fields for the ag hdr (inode section). The growth of the agi
2443 * structure over time requires that we interpret the buffer as two logical
2444 * regions delineated by the end of the unlinked list. This is due to the size
2445 * of the hash table and its location in the middle of the agi.
2446 *
2447 * For example, a request to log a field before agi_unlinked and a field after
2448 * agi_unlinked could cause us to log the entire hash table and use an excessive
2449 * amount of log space. To avoid this behavior, log the region up through
2450 * agi_unlinked in one call and the region after agi_unlinked through the end of
2451 * the structure in another.
2452 */
2453void
2454xfs_ialloc_log_agi(
2455	xfs_trans_t	*tp,		/* transaction pointer */
2456	xfs_buf_t	*bp,		/* allocation group header buffer */
2457	int		fields)		/* bitmask of fields to log */
2458{
2459	int			first;		/* first byte number */
2460	int			last;		/* last byte number */
2461	static const short	offsets[] = {	/* field starting offsets */
2462					/* keep in sync with bit definitions */
2463		offsetof(xfs_agi_t, agi_magicnum),
2464		offsetof(xfs_agi_t, agi_versionnum),
2465		offsetof(xfs_agi_t, agi_seqno),
2466		offsetof(xfs_agi_t, agi_length),
2467		offsetof(xfs_agi_t, agi_count),
2468		offsetof(xfs_agi_t, agi_root),
2469		offsetof(xfs_agi_t, agi_level),
2470		offsetof(xfs_agi_t, agi_freecount),
2471		offsetof(xfs_agi_t, agi_newino),
2472		offsetof(xfs_agi_t, agi_dirino),
2473		offsetof(xfs_agi_t, agi_unlinked),
2474		offsetof(xfs_agi_t, agi_free_root),
2475		offsetof(xfs_agi_t, agi_free_level),
 
2476		sizeof(xfs_agi_t)
2477	};
2478#ifdef DEBUG
2479	struct xfs_agi		*agi = bp->b_addr;
2480
2481	ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2482#endif
2483
2484	/*
2485	 * Compute byte offsets for the first and last fields in the first
2486	 * region and log the agi buffer. This only logs up through
2487	 * agi_unlinked.
2488	 */
2489	if (fields & XFS_AGI_ALL_BITS_R1) {
2490		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
2491				  &first, &last);
2492		xfs_trans_log_buf(tp, bp, first, last);
2493	}
2494
2495	/*
2496	 * Mask off the bits in the first region and calculate the first and
2497	 * last field offsets for any bits in the second region.
2498	 */
2499	fields &= ~XFS_AGI_ALL_BITS_R1;
2500	if (fields) {
2501		xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
2502				  &first, &last);
2503		xfs_trans_log_buf(tp, bp, first, last);
2504	}
2505}
2506
2507static xfs_failaddr_t
2508xfs_agi_verify(
2509	struct xfs_buf	*bp)
2510{
2511	struct xfs_mount *mp = bp->b_mount;
2512	struct xfs_agi	*agi = bp->b_addr;
2513	int		i;
2514
2515	if (xfs_sb_version_hascrc(&mp->m_sb)) {
2516		if (!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid))
2517			return __this_address;
2518		if (!xfs_log_check_lsn(mp, be64_to_cpu(agi->agi_lsn)))
2519			return __this_address;
2520	}
2521
2522	/*
2523	 * Validate the magic number of the agi block.
2524	 */
2525	if (!xfs_verify_magic(bp, agi->agi_magicnum))
2526		return __this_address;
2527	if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
2528		return __this_address;
2529
2530	if (be32_to_cpu(agi->agi_level) < 1 ||
2531	    be32_to_cpu(agi->agi_level) > XFS_BTREE_MAXLEVELS)
2532		return __this_address;
2533
2534	if (xfs_sb_version_hasfinobt(&mp->m_sb) &&
2535	    (be32_to_cpu(agi->agi_free_level) < 1 ||
2536	     be32_to_cpu(agi->agi_free_level) > XFS_BTREE_MAXLEVELS))
2537		return __this_address;
2538
2539	/*
2540	 * during growfs operations, the perag is not fully initialised,
2541	 * so we can't use it for any useful checking. growfs ensures we can't
2542	 * use it by using uncached buffers that don't have the perag attached
2543	 * so we can detect and avoid this problem.
2544	 */
2545	if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
2546		return __this_address;
2547
2548	for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) {
2549		if (agi->agi_unlinked[i] == cpu_to_be32(NULLAGINO))
2550			continue;
2551		if (!xfs_verify_ino(mp, be32_to_cpu(agi->agi_unlinked[i])))
2552			return __this_address;
2553	}
2554
2555	return NULL;
2556}
2557
2558static void
2559xfs_agi_read_verify(
2560	struct xfs_buf	*bp)
2561{
2562	struct xfs_mount *mp = bp->b_mount;
2563	xfs_failaddr_t	fa;
2564
2565	if (xfs_sb_version_hascrc(&mp->m_sb) &&
2566	    !xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
2567		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
2568	else {
2569		fa = xfs_agi_verify(bp);
2570		if (XFS_TEST_ERROR(fa, mp, XFS_ERRTAG_IALLOC_READ_AGI))
2571			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2572	}
2573}
2574
2575static void
2576xfs_agi_write_verify(
2577	struct xfs_buf	*bp)
2578{
2579	struct xfs_mount	*mp = bp->b_mount;
2580	struct xfs_buf_log_item	*bip = bp->b_log_item;
2581	struct xfs_agi		*agi = bp->b_addr;
2582	xfs_failaddr_t		fa;
2583
2584	fa = xfs_agi_verify(bp);
2585	if (fa) {
2586		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
2587		return;
2588	}
2589
2590	if (!xfs_sb_version_hascrc(&mp->m_sb))
2591		return;
2592
2593	if (bip)
2594		agi->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2595	xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
2596}
2597
2598const struct xfs_buf_ops xfs_agi_buf_ops = {
2599	.name = "xfs_agi",
2600	.magic = { cpu_to_be32(XFS_AGI_MAGIC), cpu_to_be32(XFS_AGI_MAGIC) },
2601	.verify_read = xfs_agi_read_verify,
2602	.verify_write = xfs_agi_write_verify,
2603	.verify_struct = xfs_agi_verify,
2604};
2605
2606/*
2607 * Read in the allocation group header (inode allocation section)
2608 */
2609int
2610xfs_read_agi(
2611	struct xfs_mount	*mp,	/* file system mount structure */
2612	struct xfs_trans	*tp,	/* transaction pointer */
2613	xfs_agnumber_t		agno,	/* allocation group number */
2614	struct xfs_buf		**bpp)	/* allocation group hdr buf */
2615{
 
2616	int			error;
2617
2618	trace_xfs_read_agi(mp, agno);
2619
2620	ASSERT(agno != NULLAGNUMBER);
2621	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
2622			XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
2623			XFS_FSS_TO_BB(mp, 1), 0, bpp, &xfs_agi_buf_ops);
2624	if (error)
2625		return error;
2626	if (tp)
2627		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_AGI_BUF);
2628
2629	xfs_buf_set_ref(*bpp, XFS_AGI_REF);
2630	return 0;
2631}
2632
 
 
 
 
2633int
2634xfs_ialloc_read_agi(
2635	struct xfs_mount	*mp,	/* file system mount structure */
2636	struct xfs_trans	*tp,	/* transaction pointer */
2637	xfs_agnumber_t		agno,	/* allocation group number */
2638	struct xfs_buf		**bpp)	/* allocation group hdr buf */
2639{
2640	struct xfs_agi		*agi;	/* allocation group header */
2641	struct xfs_perag	*pag;	/* per allocation group data */
2642	int			error;
2643
2644	trace_xfs_ialloc_read_agi(mp, agno);
2645
2646	error = xfs_read_agi(mp, tp, agno, bpp);
2647	if (error)
2648		return error;
2649
2650	agi = (*bpp)->b_addr;
2651	pag = (*bpp)->b_pag;
2652	if (!pag->pagi_init) {
2653		pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
2654		pag->pagi_count = be32_to_cpu(agi->agi_count);
2655		pag->pagi_init = 1;
2656	}
2657
2658	/*
2659	 * It's possible for these to be out of sync if
2660	 * we are in the middle of a forced shutdown.
2661	 */
2662	ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
2663		XFS_FORCED_SHUTDOWN(mp));
2664	return 0;
2665}
2666
2667/*
2668 * Read in the agi to initialise the per-ag data in the mount structure
2669 */
2670int
2671xfs_ialloc_pagi_init(
2672	xfs_mount_t	*mp,		/* file system mount structure */
2673	xfs_trans_t	*tp,		/* transaction pointer */
2674	xfs_agnumber_t	agno)		/* allocation group number */
2675{
2676	xfs_buf_t	*bp = NULL;
2677	int		error;
2678
2679	error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
2680	if (error)
2681		return error;
2682	if (bp)
2683		xfs_trans_brelse(tp, bp);
2684	return 0;
2685}
2686
2687/* Is there an inode record covering a given range of inode numbers? */
2688int
2689xfs_ialloc_has_inode_record(
2690	struct xfs_btree_cur	*cur,
2691	xfs_agino_t		low,
2692	xfs_agino_t		high,
2693	bool			*exists)
2694{
2695	struct xfs_inobt_rec_incore	irec;
2696	xfs_agino_t		agino;
2697	uint16_t		holemask;
2698	int			has_record;
2699	int			i;
2700	int			error;
2701
2702	*exists = false;
2703	error = xfs_inobt_lookup(cur, low, XFS_LOOKUP_LE, &has_record);
2704	while (error == 0 && has_record) {
2705		error = xfs_inobt_get_rec(cur, &irec, &has_record);
2706		if (error || irec.ir_startino > high)
2707			break;
2708
2709		agino = irec.ir_startino;
2710		holemask = irec.ir_holemask;
2711		for (i = 0; i < XFS_INOBT_HOLEMASK_BITS; holemask >>= 1,
2712				i++, agino += XFS_INODES_PER_HOLEMASK_BIT) {
2713			if (holemask & 1)
2714				continue;
2715			if (agino + XFS_INODES_PER_HOLEMASK_BIT > low &&
2716					agino <= high) {
2717				*exists = true;
2718				return 0;
2719			}
2720		}
2721
2722		error = xfs_btree_increment(cur, 0, &has_record);
2723	}
2724	return error;
2725}
2726
2727/* Is there an inode record covering a given extent? */
2728int
2729xfs_ialloc_has_inodes_at_extent(
2730	struct xfs_btree_cur	*cur,
2731	xfs_agblock_t		bno,
2732	xfs_extlen_t		len,
2733	bool			*exists)
2734{
2735	xfs_agino_t		low;
2736	xfs_agino_t		high;
2737
2738	low = XFS_AGB_TO_AGINO(cur->bc_mp, bno);
2739	high = XFS_AGB_TO_AGINO(cur->bc_mp, bno + len) - 1;
2740
2741	return xfs_ialloc_has_inode_record(cur, low, high, exists);
2742}
2743
2744struct xfs_ialloc_count_inodes {
2745	xfs_agino_t			count;
2746	xfs_agino_t			freecount;
2747};
2748
2749/* Record inode counts across all inobt records. */
2750STATIC int
2751xfs_ialloc_count_inodes_rec(
2752	struct xfs_btree_cur		*cur,
2753	union xfs_btree_rec		*rec,
2754	void				*priv)
2755{
2756	struct xfs_inobt_rec_incore	irec;
2757	struct xfs_ialloc_count_inodes	*ci = priv;
2758
2759	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
2760	ci->count += irec.ir_count;
2761	ci->freecount += irec.ir_freecount;
2762
2763	return 0;
2764}
2765
2766/* Count allocated and free inodes under an inobt. */
2767int
2768xfs_ialloc_count_inodes(
2769	struct xfs_btree_cur		*cur,
2770	xfs_agino_t			*count,
2771	xfs_agino_t			*freecount)
2772{
2773	struct xfs_ialloc_count_inodes	ci = {0};
2774	int				error;
2775
2776	ASSERT(cur->bc_btnum == XFS_BTNUM_INO);
2777	error = xfs_btree_query_all(cur, xfs_ialloc_count_inodes_rec, &ci);
2778	if (error)
2779		return error;
2780
2781	*count = ci.count;
2782	*freecount = ci.freecount;
2783	return 0;
2784}
2785
2786/*
2787 * Initialize inode-related geometry information.
2788 *
2789 * Compute the inode btree min and max levels and set maxicount.
2790 *
2791 * Set the inode cluster size.  This may still be overridden by the file
2792 * system block size if it is larger than the chosen cluster size.
2793 *
2794 * For v5 filesystems, scale the cluster size with the inode size to keep a
2795 * constant ratio of inode per cluster buffer, but only if mkfs has set the
2796 * inode alignment value appropriately for larger cluster sizes.
2797 *
2798 * Then compute the inode cluster alignment information.
2799 */
2800void
2801xfs_ialloc_setup_geometry(
2802	struct xfs_mount	*mp)
2803{
2804	struct xfs_sb		*sbp = &mp->m_sb;
2805	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2806	uint64_t		icount;
2807	uint			inodes;
2808
 
 
 
 
 
 
2809	/* Compute inode btree geometry. */
2810	igeo->agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
2811	igeo->inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
2812	igeo->inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
2813	igeo->inobt_mnr[0] = igeo->inobt_mxr[0] / 2;
2814	igeo->inobt_mnr[1] = igeo->inobt_mxr[1] / 2;
2815
2816	igeo->ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK,
2817			sbp->sb_inopblock);
2818	igeo->ialloc_blks = igeo->ialloc_inos >> sbp->sb_inopblog;
2819
2820	if (sbp->sb_spino_align)
2821		igeo->ialloc_min_blks = sbp->sb_spino_align;
2822	else
2823		igeo->ialloc_min_blks = igeo->ialloc_blks;
2824
2825	/* Compute and fill in value of m_ino_geo.inobt_maxlevels. */
2826	inodes = (1LL << XFS_INO_AGINO_BITS(mp)) >> XFS_INODES_PER_CHUNK_LOG;
2827	igeo->inobt_maxlevels = xfs_btree_compute_maxlevels(igeo->inobt_mnr,
2828			inodes);
 
2829
2830	/*
2831	 * Set the maximum inode count for this filesystem, being careful not
2832	 * to use obviously garbage sb_inopblog/sb_inopblock values.  Regular
2833	 * users should never get here due to failing sb verification, but
2834	 * certain users (xfs_db) need to be usable even with corrupt metadata.
2835	 */
2836	if (sbp->sb_imax_pct && igeo->ialloc_blks) {
2837		/*
2838		 * Make sure the maximum inode count is a multiple
2839		 * of the units we allocate inodes in.
2840		 */
2841		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
2842		do_div(icount, 100);
2843		do_div(icount, igeo->ialloc_blks);
2844		igeo->maxicount = XFS_FSB_TO_INO(mp,
2845				icount * igeo->ialloc_blks);
2846	} else {
2847		igeo->maxicount = 0;
2848	}
2849
2850	/*
2851	 * Compute the desired size of an inode cluster buffer size, which
2852	 * starts at 8K and (on v5 filesystems) scales up with larger inode
2853	 * sizes.
2854	 *
2855	 * Preserve the desired inode cluster size because the sparse inodes
2856	 * feature uses that desired size (not the actual size) to compute the
2857	 * sparse inode alignment.  The mount code validates this value, so we
2858	 * cannot change the behavior.
2859	 */
2860	igeo->inode_cluster_size_raw = XFS_INODE_BIG_CLUSTER_SIZE;
2861	if (xfs_sb_version_has_v3inode(&mp->m_sb)) {
2862		int	new_size = igeo->inode_cluster_size_raw;
2863
2864		new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
2865		if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
2866			igeo->inode_cluster_size_raw = new_size;
2867	}
2868
2869	/* Calculate inode cluster ratios. */
2870	if (igeo->inode_cluster_size_raw > mp->m_sb.sb_blocksize)
2871		igeo->blocks_per_cluster = XFS_B_TO_FSBT(mp,
2872				igeo->inode_cluster_size_raw);
2873	else
2874		igeo->blocks_per_cluster = 1;
2875	igeo->inode_cluster_size = XFS_FSB_TO_B(mp, igeo->blocks_per_cluster);
2876	igeo->inodes_per_cluster = XFS_FSB_TO_INO(mp, igeo->blocks_per_cluster);
2877
2878	/* Calculate inode cluster alignment. */
2879	if (xfs_sb_version_hasalign(&mp->m_sb) &&
2880	    mp->m_sb.sb_inoalignmt >= igeo->blocks_per_cluster)
2881		igeo->cluster_align = mp->m_sb.sb_inoalignmt;
2882	else
2883		igeo->cluster_align = 1;
2884	igeo->inoalign_mask = igeo->cluster_align - 1;
2885	igeo->cluster_align_inodes = XFS_FSB_TO_INO(mp, igeo->cluster_align);
2886
2887	/*
2888	 * If we are using stripe alignment, check whether
2889	 * the stripe unit is a multiple of the inode alignment
2890	 */
2891	if (mp->m_dalign && igeo->inoalign_mask &&
2892	    !(mp->m_dalign & igeo->inoalign_mask))
2893		igeo->ialloc_align = mp->m_dalign;
2894	else
2895		igeo->ialloc_align = 0;
2896}
2897
2898/* Compute the location of the root directory inode that is laid out by mkfs. */
2899xfs_ino_t
2900xfs_ialloc_calc_rootino(
2901	struct xfs_mount	*mp,
2902	int			sunit)
2903{
2904	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2905	xfs_agblock_t		first_bno;
2906
2907	/*
2908	 * Pre-calculate the geometry of AG 0.  We know what it looks like
2909	 * because libxfs knows how to create allocation groups now.
2910	 *
2911	 * first_bno is the first block in which mkfs could possibly have
2912	 * allocated the root directory inode, once we factor in the metadata
2913	 * that mkfs formats before it.  Namely, the four AG headers...
2914	 */
2915	first_bno = howmany(4 * mp->m_sb.sb_sectsize, mp->m_sb.sb_blocksize);
2916
2917	/* ...the two free space btree roots... */
2918	first_bno += 2;
2919
2920	/* ...the inode btree root... */
2921	first_bno += 1;
2922
2923	/* ...the initial AGFL... */
2924	first_bno += xfs_alloc_min_freelist(mp, NULL);
2925
2926	/* ...the free inode btree root... */
2927	if (xfs_sb_version_hasfinobt(&mp->m_sb))
2928		first_bno++;
2929
2930	/* ...the reverse mapping btree root... */
2931	if (xfs_sb_version_hasrmapbt(&mp->m_sb))
2932		first_bno++;
2933
2934	/* ...the reference count btree... */
2935	if (xfs_sb_version_hasreflink(&mp->m_sb))
2936		first_bno++;
2937
2938	/*
2939	 * ...and the log, if it is allocated in the first allocation group.
2940	 *
2941	 * This can happen with filesystems that only have a single
2942	 * allocation group, or very odd geometries created by old mkfs
2943	 * versions on very small filesystems.
2944	 */
2945	if (mp->m_sb.sb_logstart &&
2946	    XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart) == 0)
2947		 first_bno += mp->m_sb.sb_logblocks;
2948
2949	/*
2950	 * Now round first_bno up to whatever allocation alignment is given
2951	 * by the filesystem or was passed in.
2952	 */
2953	if (xfs_sb_version_hasdalign(&mp->m_sb) && igeo->ialloc_align > 0)
2954		first_bno = roundup(first_bno, sunit);
2955	else if (xfs_sb_version_hasalign(&mp->m_sb) &&
2956			mp->m_sb.sb_inoalignmt > 1)
2957		first_bno = roundup(first_bno, mp->m_sb.sb_inoalignmt);
2958
2959	return XFS_AGINO_TO_INO(mp, 0, XFS_AGB_TO_AGINO(mp, first_bno));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2960}