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v3.1
   1/*
   2 * Copyright (c) 2000-2003 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
 
 
 
 
  20#include "xfs_bit.h"
  21#include "xfs_log.h"
  22#include "xfs_inum.h"
  23#include "xfs_trans.h"
  24#include "xfs_sb.h"
  25#include "xfs_ag.h"
  26#include "xfs_alloc.h"
  27#include "xfs_quota.h"
  28#include "xfs_mount.h"
  29#include "xfs_bmap_btree.h"
  30#include "xfs_inode.h"
  31#include "xfs_bmap.h"
  32#include "xfs_rtalloc.h"
 
 
  33#include "xfs_error.h"
  34#include "xfs_itable.h"
  35#include "xfs_attr.h"
  36#include "xfs_buf_item.h"
  37#include "xfs_trans_space.h"
  38#include "xfs_trans_priv.h"
  39#include "xfs_qm.h"
 
  40#include "xfs_trace.h"
  41
 
  42
  43/*
  44   LOCK ORDER
  45
  46   inode lock		    (ilock)
  47   dquot hash-chain lock    (hashlock)
  48   xqm dquot freelist lock  (freelistlock
  49   mount's dquot list lock  (mplistlock)
  50   user dquot lock - lock ordering among dquots is based on the uid or gid
  51   group dquot lock - similar to udquots. Between the two dquots, the udquot
  52		      has to be locked first.
  53   pin lock - the dquot lock must be held to take this lock.
  54   flush lock - ditto.
  55*/
  56
  57#ifdef DEBUG
  58xfs_buftarg_t *xfs_dqerror_target;
  59int xfs_do_dqerror;
  60int xfs_dqreq_num;
  61int xfs_dqerror_mod = 33;
  62#endif
  63
  64static struct lock_class_key xfs_dquot_other_class;
  65
  66/*
  67 * Allocate and initialize a dquot. We don't always allocate fresh memory;
  68 * we try to reclaim a free dquot if the number of incore dquots are above
  69 * a threshold.
  70 * The only field inside the core that gets initialized at this point
  71 * is the d_id field. The idea is to fill in the entire q_core
  72 * when we read in the on disk dquot.
  73 */
  74STATIC xfs_dquot_t *
  75xfs_qm_dqinit(
  76	xfs_mount_t  *mp,
  77	xfs_dqid_t   id,
  78	uint	     type)
  79{
  80	xfs_dquot_t	*dqp;
  81	boolean_t	brandnewdquot;
  82
  83	brandnewdquot = xfs_qm_dqalloc_incore(&dqp);
  84	dqp->dq_flags = type;
  85	dqp->q_core.d_id = cpu_to_be32(id);
  86	dqp->q_mount = mp;
  87
  88	/*
  89	 * No need to re-initialize these if this is a reclaimed dquot.
  90	 */
  91	if (brandnewdquot) {
  92		INIT_LIST_HEAD(&dqp->q_freelist);
  93		mutex_init(&dqp->q_qlock);
  94		init_waitqueue_head(&dqp->q_pinwait);
  95
  96		/*
  97		 * Because we want to use a counting completion, complete
  98		 * the flush completion once to allow a single access to
  99		 * the flush completion without blocking.
 100		 */
 101		init_completion(&dqp->q_flush);
 102		complete(&dqp->q_flush);
 103
 104		trace_xfs_dqinit(dqp);
 105	} else {
 106		/*
 107		 * Only the q_core portion was zeroed in dqreclaim_one().
 108		 * So, we need to reset others.
 109		 */
 110		dqp->q_nrefs = 0;
 111		dqp->q_blkno = 0;
 112		INIT_LIST_HEAD(&dqp->q_mplist);
 113		INIT_LIST_HEAD(&dqp->q_hashlist);
 114		dqp->q_bufoffset = 0;
 115		dqp->q_fileoffset = 0;
 116		dqp->q_transp = NULL;
 117		dqp->q_gdquot = NULL;
 118		dqp->q_res_bcount = 0;
 119		dqp->q_res_icount = 0;
 120		dqp->q_res_rtbcount = 0;
 121		atomic_set(&dqp->q_pincount, 0);
 122		dqp->q_hash = NULL;
 123		ASSERT(list_empty(&dqp->q_freelist));
 124
 125		trace_xfs_dqreuse(dqp);
 126	}
 127
 128	/*
 129	 * In either case we need to make sure group quotas have a different
 130	 * lock class than user quotas, to make sure lockdep knows we can
 131	 * locks of one of each at the same time.
 132	 */
 133	if (!(type & XFS_DQ_USER))
 134		lockdep_set_class(&dqp->q_qlock, &xfs_dquot_other_class);
 135
 136	/*
 137	 * log item gets initialized later
 138	 */
 139	return (dqp);
 140}
 141
 142/*
 143 * This is called to free all the memory associated with a dquot
 144 */
 145void
 146xfs_qm_dqdestroy(
 147	xfs_dquot_t	*dqp)
 148{
 149	ASSERT(list_empty(&dqp->q_freelist));
 150
 151	mutex_destroy(&dqp->q_qlock);
 152	kmem_zone_free(xfs_Gqm->qm_dqzone, dqp);
 153
 154	atomic_dec(&xfs_Gqm->qm_totaldquots);
 155}
 156
 157/*
 158 * This is what a 'fresh' dquot inside a dquot chunk looks like on disk.
 159 */
 160STATIC void
 161xfs_qm_dqinit_core(
 162	xfs_dqid_t	id,
 163	uint		type,
 164	xfs_dqblk_t	*d)
 165{
 166	/*
 167	 * Caller has zero'd the entire dquot 'chunk' already.
 168	 */
 169	d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
 170	d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
 171	d->dd_diskdq.d_id = cpu_to_be32(id);
 172	d->dd_diskdq.d_flags = type;
 173}
 174
 175/*
 176 * If default limits are in force, push them into the dquot now.
 177 * We overwrite the dquot limits only if they are zero and this
 178 * is not the root dquot.
 179 */
 180void
 181xfs_qm_adjust_dqlimits(
 182	xfs_mount_t		*mp,
 183	xfs_disk_dquot_t	*d)
 184{
 185	xfs_quotainfo_t		*q = mp->m_quotainfo;
 
 
 186
 187	ASSERT(d->d_id);
 188
 189	if (q->qi_bsoftlimit && !d->d_blk_softlimit)
 190		d->d_blk_softlimit = cpu_to_be64(q->qi_bsoftlimit);
 191	if (q->qi_bhardlimit && !d->d_blk_hardlimit)
 
 
 192		d->d_blk_hardlimit = cpu_to_be64(q->qi_bhardlimit);
 
 
 193	if (q->qi_isoftlimit && !d->d_ino_softlimit)
 194		d->d_ino_softlimit = cpu_to_be64(q->qi_isoftlimit);
 195	if (q->qi_ihardlimit && !d->d_ino_hardlimit)
 196		d->d_ino_hardlimit = cpu_to_be64(q->qi_ihardlimit);
 197	if (q->qi_rtbsoftlimit && !d->d_rtb_softlimit)
 198		d->d_rtb_softlimit = cpu_to_be64(q->qi_rtbsoftlimit);
 199	if (q->qi_rtbhardlimit && !d->d_rtb_hardlimit)
 200		d->d_rtb_hardlimit = cpu_to_be64(q->qi_rtbhardlimit);
 
 
 
 201}
 202
 203/*
 204 * Check the limits and timers of a dquot and start or reset timers
 205 * if necessary.
 206 * This gets called even when quota enforcement is OFF, which makes our
 207 * life a little less complicated. (We just don't reject any quota
 208 * reservations in that case, when enforcement is off).
 209 * We also return 0 as the values of the timers in Q_GETQUOTA calls, when
 210 * enforcement's off.
 211 * In contrast, warnings are a little different in that they don't
 212 * 'automatically' get started when limits get exceeded.  They do
 213 * get reset to zero, however, when we find the count to be under
 214 * the soft limit (they are only ever set non-zero via userspace).
 215 */
 216void
 217xfs_qm_adjust_dqtimers(
 218	xfs_mount_t		*mp,
 219	xfs_disk_dquot_t	*d)
 220{
 221	ASSERT(d->d_id);
 222
 223#ifdef DEBUG
 224	if (d->d_blk_hardlimit)
 225		ASSERT(be64_to_cpu(d->d_blk_softlimit) <=
 226		       be64_to_cpu(d->d_blk_hardlimit));
 227	if (d->d_ino_hardlimit)
 228		ASSERT(be64_to_cpu(d->d_ino_softlimit) <=
 229		       be64_to_cpu(d->d_ino_hardlimit));
 230	if (d->d_rtb_hardlimit)
 231		ASSERT(be64_to_cpu(d->d_rtb_softlimit) <=
 232		       be64_to_cpu(d->d_rtb_hardlimit));
 233#endif
 234
 235	if (!d->d_btimer) {
 236		if ((d->d_blk_softlimit &&
 237		     (be64_to_cpu(d->d_bcount) >=
 238		      be64_to_cpu(d->d_blk_softlimit))) ||
 239		    (d->d_blk_hardlimit &&
 240		     (be64_to_cpu(d->d_bcount) >=
 241		      be64_to_cpu(d->d_blk_hardlimit)))) {
 242			d->d_btimer = cpu_to_be32(get_seconds() +
 243					mp->m_quotainfo->qi_btimelimit);
 244		} else {
 245			d->d_bwarns = 0;
 246		}
 247	} else {
 248		if ((!d->d_blk_softlimit ||
 249		     (be64_to_cpu(d->d_bcount) <
 250		      be64_to_cpu(d->d_blk_softlimit))) &&
 251		    (!d->d_blk_hardlimit ||
 252		    (be64_to_cpu(d->d_bcount) <
 253		     be64_to_cpu(d->d_blk_hardlimit)))) {
 254			d->d_btimer = 0;
 255		}
 256	}
 257
 258	if (!d->d_itimer) {
 259		if ((d->d_ino_softlimit &&
 260		     (be64_to_cpu(d->d_icount) >=
 261		      be64_to_cpu(d->d_ino_softlimit))) ||
 262		    (d->d_ino_hardlimit &&
 263		     (be64_to_cpu(d->d_icount) >=
 264		      be64_to_cpu(d->d_ino_hardlimit)))) {
 265			d->d_itimer = cpu_to_be32(get_seconds() +
 266					mp->m_quotainfo->qi_itimelimit);
 267		} else {
 268			d->d_iwarns = 0;
 269		}
 270	} else {
 271		if ((!d->d_ino_softlimit ||
 272		     (be64_to_cpu(d->d_icount) <
 273		      be64_to_cpu(d->d_ino_softlimit)))  &&
 274		    (!d->d_ino_hardlimit ||
 275		     (be64_to_cpu(d->d_icount) <
 276		      be64_to_cpu(d->d_ino_hardlimit)))) {
 277			d->d_itimer = 0;
 278		}
 279	}
 280
 281	if (!d->d_rtbtimer) {
 282		if ((d->d_rtb_softlimit &&
 283		     (be64_to_cpu(d->d_rtbcount) >=
 284		      be64_to_cpu(d->d_rtb_softlimit))) ||
 285		    (d->d_rtb_hardlimit &&
 286		     (be64_to_cpu(d->d_rtbcount) >=
 287		      be64_to_cpu(d->d_rtb_hardlimit)))) {
 288			d->d_rtbtimer = cpu_to_be32(get_seconds() +
 289					mp->m_quotainfo->qi_rtbtimelimit);
 290		} else {
 291			d->d_rtbwarns = 0;
 292		}
 293	} else {
 294		if ((!d->d_rtb_softlimit ||
 295		     (be64_to_cpu(d->d_rtbcount) <
 296		      be64_to_cpu(d->d_rtb_softlimit))) &&
 297		    (!d->d_rtb_hardlimit ||
 298		     (be64_to_cpu(d->d_rtbcount) <
 299		      be64_to_cpu(d->d_rtb_hardlimit)))) {
 300			d->d_rtbtimer = 0;
 301		}
 302	}
 303}
 304
 305/*
 306 * initialize a buffer full of dquots and log the whole thing
 307 */
 308STATIC void
 309xfs_qm_init_dquot_blk(
 310	xfs_trans_t	*tp,
 311	xfs_mount_t	*mp,
 312	xfs_dqid_t	id,
 313	uint		type,
 314	xfs_buf_t	*bp)
 315{
 316	struct xfs_quotainfo	*q = mp->m_quotainfo;
 317	xfs_dqblk_t	*d;
 318	int		curid, i;
 319
 320	ASSERT(tp);
 321	ASSERT(xfs_buf_islocked(bp));
 322
 323	d = bp->b_addr;
 324
 325	/*
 326	 * ID of the first dquot in the block - id's are zero based.
 327	 */
 328	curid = id - (id % q->qi_dqperchunk);
 329	ASSERT(curid >= 0);
 330	memset(d, 0, BBTOB(q->qi_dqchunklen));
 331	for (i = 0; i < q->qi_dqperchunk; i++, d++, curid++)
 332		xfs_qm_dqinit_core(curid, type, d);
 
 
 
 
 
 
 
 
 
 
 333	xfs_trans_dquot_buf(tp, bp,
 334			    (type & XFS_DQ_USER ? XFS_BLF_UDQUOT_BUF :
 335			    ((type & XFS_DQ_PROJ) ? XFS_BLF_PDQUOT_BUF :
 336			     XFS_BLF_GDQUOT_BUF)));
 337	xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
 338}
 339
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 340
 
 
 
 
 
 341
 342/*
 343 * Allocate a block and fill it with dquots.
 344 * This is called when the bmapi finds a hole.
 345 */
 346STATIC int
 347xfs_qm_dqalloc(
 348	xfs_trans_t	**tpp,
 349	xfs_mount_t	*mp,
 350	xfs_dquot_t	*dqp,
 351	xfs_inode_t	*quotip,
 352	xfs_fileoff_t	offset_fsb,
 353	xfs_buf_t	**O_bpp)
 354{
 355	xfs_fsblock_t	firstblock;
 356	xfs_bmap_free_t flist;
 357	xfs_bmbt_irec_t map;
 358	int		nmaps, error, committed;
 359	xfs_buf_t	*bp;
 360	xfs_trans_t	*tp = *tpp;
 361
 362	ASSERT(tp != NULL);
 363
 364	trace_xfs_dqalloc(dqp);
 365
 366	/*
 367	 * Initialize the bmap freelist prior to calling bmapi code.
 368	 */
 369	xfs_bmap_init(&flist, &firstblock);
 370	xfs_ilock(quotip, XFS_ILOCK_EXCL);
 371	/*
 372	 * Return if this type of quotas is turned off while we didn't
 373	 * have an inode lock
 374	 */
 375	if (XFS_IS_THIS_QUOTA_OFF(dqp)) {
 376		xfs_iunlock(quotip, XFS_ILOCK_EXCL);
 377		return (ESRCH);
 378	}
 379
 380	xfs_trans_ijoin_ref(tp, quotip, XFS_ILOCK_EXCL);
 381	nmaps = 1;
 382	if ((error = xfs_bmapi(tp, quotip,
 383			      offset_fsb, XFS_DQUOT_CLUSTER_SIZE_FSB,
 384			      XFS_BMAPI_METADATA | XFS_BMAPI_WRITE,
 385			      &firstblock,
 386			      XFS_QM_DQALLOC_SPACE_RES(mp),
 387			      &map, &nmaps, &flist))) {
 388		goto error0;
 389	}
 390	ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB);
 391	ASSERT(nmaps == 1);
 392	ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
 393	       (map.br_startblock != HOLESTARTBLOCK));
 394
 395	/*
 396	 * Keep track of the blkno to save a lookup later
 397	 */
 398	dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
 399
 400	/* now we can just get the buffer (there's nothing to read yet) */
 401	bp = xfs_trans_get_buf(tp, mp->m_ddev_targp,
 402			       dqp->q_blkno,
 403			       mp->m_quotainfo->qi_dqchunklen,
 404			       0);
 405	if (!bp || (error = xfs_buf_geterror(bp)))
 
 
 406		goto error1;
 
 
 407	/*
 408	 * Make a chunk of dquots out of this buffer and log
 409	 * the entire thing.
 410	 */
 411	xfs_qm_init_dquot_blk(tp, mp, be32_to_cpu(dqp->q_core.d_id),
 412			      dqp->dq_flags & XFS_DQ_ALLTYPES, bp);
 413
 414	/*
 415	 * xfs_bmap_finish() may commit the current transaction and
 416	 * start a second transaction if the freelist is not empty.
 417	 *
 418	 * Since we still want to modify this buffer, we need to
 419	 * ensure that the buffer is not released on commit of
 420	 * the first transaction and ensure the buffer is added to the
 421	 * second transaction.
 422	 *
 423	 * If there is only one transaction then don't stop the buffer
 424	 * from being released when it commits later on.
 425	 */
 426
 427	xfs_trans_bhold(tp, bp);
 428
 429	if ((error = xfs_bmap_finish(tpp, &flist, &committed))) {
 430		goto error1;
 431	}
 432
 433	if (committed) {
 434		tp = *tpp;
 435		xfs_trans_bjoin(tp, bp);
 436	} else {
 437		xfs_trans_bhold_release(tp, bp);
 438	}
 439
 440	*O_bpp = bp;
 441	return 0;
 442
 443      error1:
 444	xfs_bmap_cancel(&flist);
 445      error0:
 446	xfs_iunlock(quotip, XFS_ILOCK_EXCL);
 447
 448	return (error);
 449}
 450
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 451/*
 452 * Maps a dquot to the buffer containing its on-disk version.
 453 * This returns a ptr to the buffer containing the on-disk dquot
 454 * in the bpp param, and a ptr to the on-disk dquot within that buffer
 455 */
 456STATIC int
 457xfs_qm_dqtobp(
 458	xfs_trans_t		**tpp,
 459	xfs_dquot_t		*dqp,
 460	xfs_disk_dquot_t	**O_ddpp,
 461	xfs_buf_t		**O_bpp,
 462	uint			flags)
 463{
 464	xfs_bmbt_irec_t map;
 465	int		nmaps = 1, error;
 466	xfs_buf_t	*bp;
 467	xfs_inode_t	*quotip = XFS_DQ_TO_QIP(dqp);
 468	xfs_mount_t	*mp = dqp->q_mount;
 469	xfs_disk_dquot_t *ddq;
 470	xfs_dqid_t	id = be32_to_cpu(dqp->q_core.d_id);
 471	xfs_trans_t	*tp = (tpp ? *tpp : NULL);
 472
 473	dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
 474
 475	xfs_ilock(quotip, XFS_ILOCK_SHARED);
 476	if (XFS_IS_THIS_QUOTA_OFF(dqp)) {
 477		/*
 478		 * Return if this type of quotas is turned off while we
 479		 * didn't have the quota inode lock.
 480		 */
 481		xfs_iunlock(quotip, XFS_ILOCK_SHARED);
 482		return ESRCH;
 483	}
 484
 485	/*
 486	 * Find the block map; no allocations yet
 487	 */
 488	error = xfs_bmapi(NULL, quotip, dqp->q_fileoffset,
 489			  XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA,
 490			  NULL, 0, &map, &nmaps, NULL);
 491
 492	xfs_iunlock(quotip, XFS_ILOCK_SHARED);
 493	if (error)
 494		return error;
 495
 496	ASSERT(nmaps == 1);
 497	ASSERT(map.br_blockcount == 1);
 498
 499	/*
 500	 * Offset of dquot in the (fixed sized) dquot chunk.
 501	 */
 502	dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) *
 503		sizeof(xfs_dqblk_t);
 504
 505	ASSERT(map.br_startblock != DELAYSTARTBLOCK);
 506	if (map.br_startblock == HOLESTARTBLOCK) {
 507		/*
 508		 * We don't allocate unless we're asked to
 509		 */
 510		if (!(flags & XFS_QMOPT_DQALLOC))
 511			return ENOENT;
 512
 513		ASSERT(tp);
 514		error = xfs_qm_dqalloc(tpp, mp, dqp, quotip,
 515					dqp->q_fileoffset, &bp);
 516		if (error)
 517			return error;
 518		tp = *tpp;
 519	} else {
 520		trace_xfs_dqtobp_read(dqp);
 521
 522		/*
 523		 * store the blkno etc so that we don't have to do the
 524		 * mapping all the time
 525		 */
 526		dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
 527
 528		error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
 529					   dqp->q_blkno,
 530					   mp->m_quotainfo->qi_dqchunklen,
 531					   0, &bp);
 532		if (error || !bp)
 533			return XFS_ERROR(error);
 534	}
 535
 536	ASSERT(xfs_buf_islocked(bp));
 537
 538	/*
 539	 * calculate the location of the dquot inside the buffer.
 540	 */
 541	ddq = bp->b_addr + dqp->q_bufoffset;
 
 
 542
 543	/*
 544	 * A simple sanity check in case we got a corrupted dquot...
 545	 */
 546	error = xfs_qm_dqcheck(mp, ddq, id, dqp->dq_flags & XFS_DQ_ALLTYPES,
 547			   flags & (XFS_QMOPT_DQREPAIR|XFS_QMOPT_DOWARN),
 548			   "dqtobp");
 549	if (error) {
 550		if (!(flags & XFS_QMOPT_DQREPAIR)) {
 551			xfs_trans_brelse(tp, bp);
 552			return XFS_ERROR(EIO);
 553		}
 554	}
 555
 
 556	*O_bpp = bp;
 557	*O_ddpp = ddq;
 558
 559	return (0);
 560}
 561
 562
 563/*
 564 * Read in the ondisk dquot using dqtobp() then copy it to an incore version,
 565 * and release the buffer immediately.
 566 *
 
 567 */
 568/* ARGSUSED */
 569STATIC int
 570xfs_qm_dqread(
 571	xfs_trans_t	**tpp,
 572	xfs_dqid_t	id,
 573	xfs_dquot_t	*dqp,	/* dquot to get filled in */
 574	uint		flags)
 
 575{
 576	xfs_disk_dquot_t *ddqp;
 577	xfs_buf_t	 *bp;
 578	int		 error;
 579	xfs_trans_t	 *tp;
 
 
 580
 581	ASSERT(tpp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 582
 583	trace_xfs_dqread(dqp);
 584
 
 
 
 
 
 
 
 
 
 585	/*
 586	 * get a pointer to the on-disk dquot and the buffer containing it
 587	 * dqp already knows its own type (GROUP/USER).
 588	 */
 589	if ((error = xfs_qm_dqtobp(tpp, dqp, &ddqp, &bp, flags))) {
 590		return (error);
 
 
 
 
 
 
 
 
 591	}
 592	tp = *tpp;
 593
 594	/* copy everything from disk dquot to the incore dquot */
 595	memcpy(&dqp->q_core, ddqp, sizeof(xfs_disk_dquot_t));
 596	ASSERT(be32_to_cpu(dqp->q_core.d_id) == id);
 597	xfs_qm_dquot_logitem_init(dqp);
 598
 599	/*
 600	 * Reservation counters are defined as reservation plus current usage
 601	 * to avoid having to add every time.
 602	 */
 603	dqp->q_res_bcount = be64_to_cpu(ddqp->d_bcount);
 604	dqp->q_res_icount = be64_to_cpu(ddqp->d_icount);
 605	dqp->q_res_rtbcount = be64_to_cpu(ddqp->d_rtbcount);
 606
 
 
 
 607	/* Mark the buf so that this will stay incore a little longer */
 608	XFS_BUF_SET_VTYPE_REF(bp, B_FS_DQUOT, XFS_DQUOT_REF);
 609
 610	/*
 611	 * We got the buffer with a xfs_trans_read_buf() (in dqtobp())
 612	 * So we need to release with xfs_trans_brelse().
 613	 * The strategy here is identical to that of inodes; we lock
 614	 * the dquot in xfs_qm_dqget() before making it accessible to
 615	 * others. This is because dquots, like inodes, need a good level of
 616	 * concurrency, and we don't want to take locks on the entire buffers
 617	 * for dquot accesses.
 618	 * Note also that the dquot buffer may even be dirty at this point, if
 619	 * this particular dquot was repaired. We still aren't afraid to
 620	 * brelse it because we have the changes incore.
 621	 */
 622	ASSERT(xfs_buf_islocked(bp));
 623	xfs_trans_brelse(tp, bp);
 624
 625	return (error);
 626}
 627
 628
 629/*
 630 * allocate an incore dquot from the kernel heap,
 631 * and fill its core with quota information kept on disk.
 632 * If XFS_QMOPT_DQALLOC is set, it'll allocate a dquot on disk
 633 * if it wasn't already allocated.
 634 */
 635STATIC int
 636xfs_qm_idtodq(
 637	xfs_mount_t	*mp,
 638	xfs_dqid_t	id,	 /* gid or uid, depending on type */
 639	uint		type,	 /* UDQUOT or GDQUOT */
 640	uint		flags,	 /* DQALLOC, DQREPAIR */
 641	xfs_dquot_t	**O_dqpp)/* OUT : incore dquot, not locked */
 642{
 643	xfs_dquot_t	*dqp;
 644	int		error;
 645	xfs_trans_t	*tp;
 646	int		cancelflags=0;
 647
 648	dqp = xfs_qm_dqinit(mp, id, type);
 649	tp = NULL;
 650	if (flags & XFS_QMOPT_DQALLOC) {
 651		tp = xfs_trans_alloc(mp, XFS_TRANS_QM_DQALLOC);
 652		error = xfs_trans_reserve(tp, XFS_QM_DQALLOC_SPACE_RES(mp),
 653				XFS_WRITE_LOG_RES(mp) +
 654				BBTOB(mp->m_quotainfo->qi_dqchunklen) - 1 +
 655				128,
 656				0,
 657				XFS_TRANS_PERM_LOG_RES,
 658				XFS_WRITE_LOG_COUNT);
 659		if (error) {
 660			cancelflags = 0;
 661			goto error0;
 662		}
 663		cancelflags = XFS_TRANS_RELEASE_LOG_RES;
 664	}
 665
 666	/*
 667	 * Read it from disk; xfs_dqread() takes care of
 668	 * all the necessary initialization of dquot's fields (locks, etc)
 669	 */
 670	if ((error = xfs_qm_dqread(&tp, id, dqp, flags))) {
 671		/*
 672		 * This can happen if quotas got turned off (ESRCH),
 673		 * or if the dquot didn't exist on disk and we ask to
 674		 * allocate (ENOENT).
 675		 */
 676		trace_xfs_dqread_fail(dqp);
 677		cancelflags |= XFS_TRANS_ABORT;
 678		goto error0;
 679	}
 680	if (tp) {
 681		if ((error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES)))
 682			goto error1;
 
 683	}
 684
 685	*O_dqpp = dqp;
 686	return (0);
 687
 688 error0:
 689	ASSERT(error);
 690	if (tp)
 691		xfs_trans_cancel(tp, cancelflags);
 692 error1:
 693	xfs_qm_dqdestroy(dqp);
 694	*O_dqpp = NULL;
 695	return (error);
 696}
 697
 698/*
 699 * Lookup a dquot in the incore dquot hashtable. We keep two separate
 700 * hashtables for user and group dquots; and, these are global tables
 701 * inside the XQM, not per-filesystem tables.
 702 * The hash chain must be locked by caller, and it is left locked
 703 * on return. Returning dquot is locked.
 704 */
 705STATIC int
 706xfs_qm_dqlookup(
 707	xfs_mount_t		*mp,
 708	xfs_dqid_t		id,
 709	xfs_dqhash_t		*qh,
 710	xfs_dquot_t		**O_dqpp)
 711{
 712	xfs_dquot_t		*dqp;
 713	uint			flist_locked;
 714
 715	ASSERT(mutex_is_locked(&qh->qh_lock));
 716
 717	flist_locked = B_FALSE;
 718
 719	/*
 720	 * Traverse the hashchain looking for a match
 721	 */
 722	list_for_each_entry(dqp, &qh->qh_list, q_hashlist) {
 723		/*
 724		 * We already have the hashlock. We don't need the
 725		 * dqlock to look at the id field of the dquot, since the
 726		 * id can't be modified without the hashlock anyway.
 727		 */
 728		if (be32_to_cpu(dqp->q_core.d_id) == id && dqp->q_mount == mp) {
 729			trace_xfs_dqlookup_found(dqp);
 730
 731			/*
 732			 * All in core dquots must be on the dqlist of mp
 733			 */
 734			ASSERT(!list_empty(&dqp->q_mplist));
 735
 736			xfs_dqlock(dqp);
 737			if (dqp->q_nrefs == 0) {
 738				ASSERT(!list_empty(&dqp->q_freelist));
 739				if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) {
 740					trace_xfs_dqlookup_want(dqp);
 741
 742					/*
 743					 * We may have raced with dqreclaim_one()
 744					 * (and lost). So, flag that we don't
 745					 * want the dquot to be reclaimed.
 746					 */
 747					dqp->dq_flags |= XFS_DQ_WANT;
 748					xfs_dqunlock(dqp);
 749					mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
 750					xfs_dqlock(dqp);
 751					dqp->dq_flags &= ~(XFS_DQ_WANT);
 752				}
 753				flist_locked = B_TRUE;
 754			}
 755
 756			/*
 757			 * id couldn't have changed; we had the hashlock all
 758			 * along
 759			 */
 760			ASSERT(be32_to_cpu(dqp->q_core.d_id) == id);
 761
 762			if (flist_locked) {
 763				if (dqp->q_nrefs != 0) {
 764					mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
 765					flist_locked = B_FALSE;
 766				} else {
 767					/* take it off the freelist */
 768					trace_xfs_dqlookup_freelist(dqp);
 769					list_del_init(&dqp->q_freelist);
 770					xfs_Gqm->qm_dqfrlist_cnt--;
 771				}
 772			}
 773
 774			XFS_DQHOLD(dqp);
 775
 776			if (flist_locked)
 777				mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
 778			/*
 779			 * move the dquot to the front of the hashchain
 780			 */
 781			ASSERT(mutex_is_locked(&qh->qh_lock));
 782			list_move(&dqp->q_hashlist, &qh->qh_list);
 783			trace_xfs_dqlookup_done(dqp);
 784			*O_dqpp = dqp;
 785			return 0;
 786		}
 787	}
 788
 789	*O_dqpp = NULL;
 790	ASSERT(mutex_is_locked(&qh->qh_lock));
 791	return (1);
 792}
 793
 794/*
 795 * Given the file system, inode OR id, and type (UDQUOT/GDQUOT), return a
 796 * a locked dquot, doing an allocation (if requested) as needed.
 797 * When both an inode and an id are given, the inode's id takes precedence.
 798 * That is, if the id changes while we don't hold the ilock inside this
 799 * function, the new dquot is returned, not necessarily the one requested
 800 * in the id argument.
 801 */
 802int
 803xfs_qm_dqget(
 804	xfs_mount_t	*mp,
 805	xfs_inode_t	*ip,	  /* locked inode (optional) */
 806	xfs_dqid_t	id,	  /* uid/projid/gid depending on type */
 807	uint		type,	  /* XFS_DQ_USER/XFS_DQ_PROJ/XFS_DQ_GROUP */
 808	uint		flags,	  /* DQALLOC, DQSUSER, DQREPAIR, DOWARN */
 809	xfs_dquot_t	**O_dqpp) /* OUT : locked incore dquot */
 810{
 811	xfs_dquot_t	*dqp;
 812	xfs_dqhash_t	*h;
 813	uint		version;
 814	int		error;
 815
 816	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
 817	if ((! XFS_IS_UQUOTA_ON(mp) && type == XFS_DQ_USER) ||
 818	    (! XFS_IS_PQUOTA_ON(mp) && type == XFS_DQ_PROJ) ||
 819	    (! XFS_IS_GQUOTA_ON(mp) && type == XFS_DQ_GROUP)) {
 820		return (ESRCH);
 821	}
 822	h = XFS_DQ_HASH(mp, id, type);
 823
 824#ifdef DEBUG
 825	if (xfs_do_dqerror) {
 826		if ((xfs_dqerror_target == mp->m_ddev_targp) &&
 827		    (xfs_dqreq_num++ % xfs_dqerror_mod) == 0) {
 828			xfs_debug(mp, "Returning error in dqget");
 829			return (EIO);
 830		}
 831	}
 832#endif
 833
 834 again:
 835
 836#ifdef DEBUG
 837	ASSERT(type == XFS_DQ_USER ||
 838	       type == XFS_DQ_PROJ ||
 839	       type == XFS_DQ_GROUP);
 840	if (ip) {
 841		ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 842		if (type == XFS_DQ_USER)
 843			ASSERT(ip->i_udquot == NULL);
 844		else
 845			ASSERT(ip->i_gdquot == NULL);
 846	}
 847#endif
 848	mutex_lock(&h->qh_lock);
 849
 850	/*
 851	 * Look in the cache (hashtable).
 852	 * The chain is kept locked during lookup.
 853	 */
 854	if (xfs_qm_dqlookup(mp, id, h, O_dqpp) == 0) {
 855		XQM_STATS_INC(xqmstats.xs_qm_dqcachehits);
 856		/*
 857		 * The dquot was found, moved to the front of the chain,
 858		 * taken off the freelist if it was on it, and locked
 859		 * at this point. Just unlock the hashchain and return.
 860		 */
 861		ASSERT(*O_dqpp);
 862		ASSERT(XFS_DQ_IS_LOCKED(*O_dqpp));
 863		mutex_unlock(&h->qh_lock);
 864		trace_xfs_dqget_hit(*O_dqpp);
 865		return (0);	/* success */
 
 
 
 
 866	}
 867	XQM_STATS_INC(xqmstats.xs_qm_dqcachemisses);
 
 868
 869	/*
 870	 * Dquot cache miss. We don't want to keep the inode lock across
 871	 * a (potential) disk read. Also we don't want to deal with the lock
 872	 * ordering between quotainode and this inode. OTOH, dropping the inode
 873	 * lock here means dealing with a chown that can happen before
 874	 * we re-acquire the lock.
 875	 */
 876	if (ip)
 877		xfs_iunlock(ip, XFS_ILOCK_EXCL);
 878	/*
 879	 * Save the hashchain version stamp, and unlock the chain, so that
 880	 * we don't keep the lock across a disk read
 881	 */
 882	version = h->qh_version;
 883	mutex_unlock(&h->qh_lock);
 884
 885	/*
 886	 * Allocate the dquot on the kernel heap, and read the ondisk
 887	 * portion off the disk. Also, do all the necessary initialization
 888	 * This can return ENOENT if dquot didn't exist on disk and we didn't
 889	 * ask it to allocate; ESRCH if quotas got turned off suddenly.
 890	 */
 891	if ((error = xfs_qm_idtodq(mp, id, type,
 892				  flags & (XFS_QMOPT_DQALLOC|XFS_QMOPT_DQREPAIR|
 893					   XFS_QMOPT_DOWARN),
 894				  &dqp))) {
 895		if (ip)
 896			xfs_ilock(ip, XFS_ILOCK_EXCL);
 897		return (error);
 898	}
 899
 900	/*
 901	 * See if this is mount code calling to look at the overall quota limits
 902	 * which are stored in the id == 0 user or group's dquot.
 903	 * Since we may not have done a quotacheck by this point, just return
 904	 * the dquot without attaching it to any hashtables, lists, etc, or even
 905	 * taking a reference.
 906	 * The caller must dqdestroy this once done.
 907	 */
 908	if (flags & XFS_QMOPT_DQSUSER) {
 909		ASSERT(id == 0);
 910		ASSERT(! ip);
 911		goto dqret;
 912	}
 913
 914	/*
 915	 * Dquot lock comes after hashlock in the lock ordering
 916	 */
 917	if (ip) {
 918		xfs_ilock(ip, XFS_ILOCK_EXCL);
 919
 
 
 
 
 920		/*
 921		 * A dquot could be attached to this inode by now, since
 922		 * we had dropped the ilock.
 923		 */
 924		if (type == XFS_DQ_USER) {
 925			if (!XFS_IS_UQUOTA_ON(mp)) {
 926				/* inode stays locked on return */
 927				xfs_qm_dqdestroy(dqp);
 928				return XFS_ERROR(ESRCH);
 929			}
 930			if (ip->i_udquot) {
 931				xfs_qm_dqdestroy(dqp);
 932				dqp = ip->i_udquot;
 933				xfs_dqlock(dqp);
 934				goto dqret;
 935			}
 936		} else {
 937			if (!XFS_IS_OQUOTA_ON(mp)) {
 938				/* inode stays locked on return */
 939				xfs_qm_dqdestroy(dqp);
 940				return XFS_ERROR(ESRCH);
 941			}
 942			if (ip->i_gdquot) {
 943				xfs_qm_dqdestroy(dqp);
 944				dqp = ip->i_gdquot;
 945				xfs_dqlock(dqp);
 946				goto dqret;
 947			}
 948		}
 949	}
 950
 951	/*
 952	 * Hashlock comes after ilock in lock order
 953	 */
 954	mutex_lock(&h->qh_lock);
 955	if (version != h->qh_version) {
 956		xfs_dquot_t *tmpdqp;
 957		/*
 958		 * Now, see if somebody else put the dquot in the
 959		 * hashtable before us. This can happen because we didn't
 960		 * keep the hashchain lock. We don't have to worry about
 961		 * lock order between the two dquots here since dqp isn't
 962		 * on any findable lists yet.
 963		 */
 964		if (xfs_qm_dqlookup(mp, id, h, &tmpdqp) == 0) {
 965			/*
 966			 * Duplicate found. Just throw away the new dquot
 967			 * and start over.
 968			 */
 969			xfs_qm_dqput(tmpdqp);
 970			mutex_unlock(&h->qh_lock);
 971			xfs_qm_dqdestroy(dqp);
 972			XQM_STATS_INC(xqmstats.xs_qm_dquot_dups);
 973			goto again;
 974		}
 975	}
 976
 977	/*
 978	 * Put the dquot at the beginning of the hash-chain and mp's list
 979	 * LOCK ORDER: hashlock, freelistlock, mplistlock, udqlock, gdqlock ..
 980	 */
 981	ASSERT(mutex_is_locked(&h->qh_lock));
 982	dqp->q_hash = h;
 983	list_add(&dqp->q_hashlist, &h->qh_list);
 984	h->qh_version++;
 985
 986	/*
 987	 * Attach this dquot to this filesystem's list of all dquots,
 988	 * kept inside the mount structure in m_quotainfo field
 989	 */
 990	mutex_lock(&mp->m_quotainfo->qi_dqlist_lock);
 991
 992	/*
 993	 * We return a locked dquot to the caller, with a reference taken
 994	 */
 995	xfs_dqlock(dqp);
 996	dqp->q_nrefs = 1;
 997
 998	list_add(&dqp->q_mplist, &mp->m_quotainfo->qi_dqlist);
 999	mp->m_quotainfo->qi_dquots++;
1000	mutex_unlock(&mp->m_quotainfo->qi_dqlist_lock);
1001	mutex_unlock(&h->qh_lock);
1002 dqret:
1003	ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL));
1004	trace_xfs_dqget_miss(dqp);
1005	*O_dqpp = dqp;
1006	return (0);
1007}
1008
1009
1010/*
1011 * Release a reference to the dquot (decrement ref-count)
1012 * and unlock it. If there is a group quota attached to this
1013 * dquot, carefully release that too without tripping over
1014 * deadlocks'n'stuff.
1015 */
1016void
1017xfs_qm_dqput(
1018	xfs_dquot_t	*dqp)
1019{
1020	xfs_dquot_t	*gdqp;
 
 
1021
1022	ASSERT(dqp->q_nrefs > 0);
1023	ASSERT(XFS_DQ_IS_LOCKED(dqp));
1024
1025	trace_xfs_dqput(dqp);
 
1026
1027	if (dqp->q_nrefs != 1) {
1028		dqp->q_nrefs--;
1029		xfs_dqunlock(dqp);
1030		return;
 
 
 
 
 
1031	}
1032
 
 
 
 
 
 
 
1033	/*
1034	 * drop the dqlock and acquire the freelist and dqlock
1035	 * in the right order; but try to get it out-of-order first
1036	 */
1037	if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) {
1038		trace_xfs_dqput_wait(dqp);
1039		xfs_dqunlock(dqp);
1040		mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
1041		xfs_dqlock(dqp);
1042	}
1043
1044	while (1) {
1045		gdqp = NULL;
 
 
 
 
 
 
 
 
 
 
1046
1047		/* We can't depend on nrefs being == 1 here */
1048		if (--dqp->q_nrefs == 0) {
1049			trace_xfs_dqput_free(dqp);
1050
1051			list_add_tail(&dqp->q_freelist, &xfs_Gqm->qm_dqfrlist);
1052			xfs_Gqm->qm_dqfrlist_cnt++;
1053
1054			/*
1055			 * If we just added a udquot to the freelist, then
1056			 * we want to release the gdquot reference that
1057			 * it (probably) has. Otherwise it'll keep the
1058			 * gdquot from getting reclaimed.
1059			 */
1060			if ((gdqp = dqp->q_gdquot)) {
1061				/*
1062				 * Avoid a recursive dqput call
1063				 */
1064				xfs_dqlock(gdqp);
1065				dqp->q_gdquot = NULL;
1066			}
1067		}
1068		xfs_dqunlock(dqp);
1069
1070		/*
1071		 * If we had a group quota inside the user quota as a hint,
1072		 * release it now.
1073		 */
1074		if (! gdqp)
1075			break;
1076		dqp = gdqp;
1077	}
1078	mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
1079}
1080
1081/*
1082 * Release a dquot. Flush it if dirty, then dqput() it.
1083 * dquot must not be locked.
1084 */
1085void
1086xfs_qm_dqrele(
1087	xfs_dquot_t	*dqp)
1088{
1089	if (!dqp)
1090		return;
1091
1092	trace_xfs_dqrele(dqp);
1093
1094	xfs_dqlock(dqp);
1095	/*
1096	 * We don't care to flush it if the dquot is dirty here.
1097	 * That will create stutters that we want to avoid.
1098	 * Instead we do a delayed write when we try to reclaim
1099	 * a dirty dquot. Also xfs_sync will take part of the burden...
1100	 */
1101	xfs_qm_dqput(dqp);
1102}
1103
1104/*
1105 * This is the dquot flushing I/O completion routine.  It is called
1106 * from interrupt level when the buffer containing the dquot is
1107 * flushed to disk.  It is responsible for removing the dquot logitem
1108 * from the AIL if it has not been re-logged, and unlocking the dquot's
1109 * flush lock. This behavior is very similar to that of inodes..
1110 */
1111STATIC void
1112xfs_qm_dqflush_done(
1113	struct xfs_buf		*bp,
1114	struct xfs_log_item	*lip)
1115{
1116	xfs_dq_logitem_t	*qip = (struct xfs_dq_logitem *)lip;
1117	xfs_dquot_t		*dqp = qip->qli_dquot;
1118	struct xfs_ail		*ailp = lip->li_ailp;
1119
1120	/*
1121	 * We only want to pull the item from the AIL if its
1122	 * location in the log has not changed since we started the flush.
1123	 * Thus, we only bother if the dquot's lsn has
1124	 * not changed. First we check the lsn outside the lock
1125	 * since it's cheaper, and then we recheck while
1126	 * holding the lock before removing the dquot from the AIL.
1127	 */
1128	if ((lip->li_flags & XFS_LI_IN_AIL) &&
1129	    lip->li_lsn == qip->qli_flush_lsn) {
1130
1131		/* xfs_trans_ail_delete() drops the AIL lock. */
1132		spin_lock(&ailp->xa_lock);
1133		if (lip->li_lsn == qip->qli_flush_lsn)
1134			xfs_trans_ail_delete(ailp, lip);
1135		else
1136			spin_unlock(&ailp->xa_lock);
1137	}
1138
1139	/*
1140	 * Release the dq's flush lock since we're done with it.
1141	 */
1142	xfs_dqfunlock(dqp);
1143}
1144
1145/*
1146 * Write a modified dquot to disk.
1147 * The dquot must be locked and the flush lock too taken by caller.
1148 * The flush lock will not be unlocked until the dquot reaches the disk,
1149 * but the dquot is free to be unlocked and modified by the caller
1150 * in the interim. Dquot is still locked on return. This behavior is
1151 * identical to that of inodes.
1152 */
1153int
1154xfs_qm_dqflush(
1155	xfs_dquot_t		*dqp,
1156	uint			flags)
1157{
1158	struct xfs_mount	*mp = dqp->q_mount;
1159	struct xfs_buf		*bp;
1160	struct xfs_disk_dquot	*ddqp;
1161	int			error;
1162
1163	ASSERT(XFS_DQ_IS_LOCKED(dqp));
1164	ASSERT(!completion_done(&dqp->q_flush));
1165
1166	trace_xfs_dqflush(dqp);
1167
1168	/*
1169	 * If not dirty, or it's pinned and we are not supposed to block, nada.
1170	 */
1171	if (!XFS_DQ_IS_DIRTY(dqp) ||
1172	    (!(flags & SYNC_WAIT) && atomic_read(&dqp->q_pincount) > 0)) {
1173		xfs_dqfunlock(dqp);
1174		return 0;
1175	}
1176	xfs_qm_dqunpin_wait(dqp);
1177
1178	/*
1179	 * This may have been unpinned because the filesystem is shutting
1180	 * down forcibly. If that's the case we must not write this dquot
1181	 * to disk, because the log record didn't make it to disk!
 
 
 
1182	 */
1183	if (XFS_FORCED_SHUTDOWN(mp)) {
 
1184		dqp->dq_flags &= ~XFS_DQ_DIRTY;
1185		xfs_dqfunlock(dqp);
1186		return XFS_ERROR(EIO);
 
 
 
 
 
 
 
1187	}
1188
1189	/*
1190	 * Get the buffer containing the on-disk dquot
1191	 */
1192	error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno,
1193				   mp->m_quotainfo->qi_dqchunklen, 0, &bp);
1194	if (error) {
1195		ASSERT(error != ENOENT);
1196		xfs_dqfunlock(dqp);
1197		return error;
1198	}
1199
1200	/*
1201	 * Calculate the location of the dquot inside the buffer.
1202	 */
1203	ddqp = bp->b_addr + dqp->q_bufoffset;
1204
1205	/*
1206	 * A simple sanity check in case we got a corrupted dquot..
1207	 */
1208	error = xfs_qm_dqcheck(mp, &dqp->q_core, be32_to_cpu(ddqp->d_id), 0,
1209			   XFS_QMOPT_DOWARN, "dqflush (incore copy)");
1210	if (error) {
1211		xfs_buf_relse(bp);
1212		xfs_dqfunlock(dqp);
1213		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1214		return XFS_ERROR(EIO);
1215	}
1216
1217	/* This is the only portion of data that needs to persist */
1218	memcpy(ddqp, &dqp->q_core, sizeof(xfs_disk_dquot_t));
1219
1220	/*
1221	 * Clear the dirty field and remember the flush lsn for later use.
1222	 */
1223	dqp->dq_flags &= ~XFS_DQ_DIRTY;
1224
1225	xfs_trans_ail_copy_lsn(mp->m_ail, &dqp->q_logitem.qli_flush_lsn,
1226					&dqp->q_logitem.qli_item.li_lsn);
1227
1228	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1229	 * Attach an iodone routine so that we can remove this dquot from the
1230	 * AIL and release the flush lock once the dquot is synced to disk.
1231	 */
1232	xfs_buf_attach_iodone(bp, xfs_qm_dqflush_done,
1233				  &dqp->q_logitem.qli_item);
1234
1235	/*
1236	 * If the buffer is pinned then push on the log so we won't
1237	 * get stuck waiting in the write for too long.
1238	 */
1239	if (xfs_buf_ispinned(bp)) {
1240		trace_xfs_dqflush_force(dqp);
1241		xfs_log_force(mp, 0);
1242	}
1243
1244	if (flags & SYNC_WAIT)
1245		error = xfs_bwrite(mp, bp);
1246	else
1247		xfs_bdwrite(mp, bp);
1248
1249	trace_xfs_dqflush_done(dqp);
 
 
1250
1251	/*
1252	 * dqp is still locked, but caller is free to unlock it now.
1253	 */
1254	return error;
1255
1256}
1257
1258int
1259xfs_qm_dqlock_nowait(
1260	xfs_dquot_t *dqp)
1261{
1262	return mutex_trylock(&dqp->q_qlock);
1263}
1264
1265void
1266xfs_dqlock(
1267	xfs_dquot_t *dqp)
1268{
1269	mutex_lock(&dqp->q_qlock);
1270}
1271
1272void
1273xfs_dqunlock(
1274	xfs_dquot_t *dqp)
1275{
1276	mutex_unlock(&(dqp->q_qlock));
1277	if (dqp->q_logitem.qli_dquot == dqp) {
1278		/* Once was dqp->q_mount, but might just have been cleared */
1279		xfs_trans_unlocked_item(dqp->q_logitem.qli_item.li_ailp,
1280					(xfs_log_item_t*)&(dqp->q_logitem));
1281	}
1282}
1283
1284
1285void
1286xfs_dqunlock_nonotify(
1287	xfs_dquot_t *dqp)
1288{
1289	mutex_unlock(&(dqp->q_qlock));
1290}
1291
1292/*
1293 * Lock two xfs_dquot structures.
1294 *
1295 * To avoid deadlocks we always lock the quota structure with
1296 * the lowerd id first.
1297 */
1298void
1299xfs_dqlock2(
1300	xfs_dquot_t	*d1,
1301	xfs_dquot_t	*d2)
1302{
1303	if (d1 && d2) {
1304		ASSERT(d1 != d2);
1305		if (be32_to_cpu(d1->q_core.d_id) >
1306		    be32_to_cpu(d2->q_core.d_id)) {
1307			mutex_lock(&d2->q_qlock);
1308			mutex_lock_nested(&d1->q_qlock, XFS_QLOCK_NESTED);
1309		} else {
1310			mutex_lock(&d1->q_qlock);
1311			mutex_lock_nested(&d2->q_qlock, XFS_QLOCK_NESTED);
1312		}
1313	} else if (d1) {
1314		mutex_lock(&d1->q_qlock);
1315	} else if (d2) {
1316		mutex_lock(&d2->q_qlock);
1317	}
1318}
1319
1320
1321/*
1322 * Take a dquot out of the mount's dqlist as well as the hashlist.
1323 * This is called via unmount as well as quotaoff, and the purge
1324 * will always succeed unless there are soft (temp) references
1325 * outstanding.
1326 *
1327 * This returns 0 if it was purged, 1 if it wasn't. It's not an error code
1328 * that we're returning! XXXsup - not cool.
1329 */
1330/* ARGSUSED */
1331int
1332xfs_qm_dqpurge(
1333	xfs_dquot_t	*dqp)
1334{
1335	xfs_dqhash_t	*qh = dqp->q_hash;
1336	xfs_mount_t	*mp = dqp->q_mount;
1337
1338	ASSERT(mutex_is_locked(&mp->m_quotainfo->qi_dqlist_lock));
1339	ASSERT(mutex_is_locked(&dqp->q_hash->qh_lock));
1340
1341	xfs_dqlock(dqp);
1342	/*
1343	 * We really can't afford to purge a dquot that is
1344	 * referenced, because these are hard refs.
1345	 * It shouldn't happen in general because we went thru _all_ inodes in
1346	 * dqrele_all_inodes before calling this and didn't let the mountlock go.
1347	 * However it is possible that we have dquots with temporary
1348	 * references that are not attached to an inode. e.g. see xfs_setattr().
1349	 */
1350	if (dqp->q_nrefs != 0) {
1351		xfs_dqunlock(dqp);
1352		mutex_unlock(&dqp->q_hash->qh_lock);
1353		return (1);
1354	}
1355
1356	ASSERT(!list_empty(&dqp->q_freelist));
1357
1358	/*
1359	 * If we're turning off quotas, we have to make sure that, for
1360	 * example, we don't delete quota disk blocks while dquots are
1361	 * in the process of getting written to those disk blocks.
1362	 * This dquot might well be on AIL, and we can't leave it there
1363	 * if we're turning off quotas. Basically, we need this flush
1364	 * lock, and are willing to block on it.
1365	 */
1366	if (!xfs_dqflock_nowait(dqp)) {
1367		/*
1368		 * Block on the flush lock after nudging dquot buffer,
1369		 * if it is incore.
1370		 */
1371		xfs_qm_dqflock_pushbuf_wait(dqp);
1372	}
1373
1374	/*
1375	 * XXXIf we're turning this type of quotas off, we don't care
1376	 * about the dirty metadata sitting in this dquot. OTOH, if
1377	 * we're unmounting, we do care, so we flush it and wait.
1378	 */
1379	if (XFS_DQ_IS_DIRTY(dqp)) {
1380		int	error;
1381
1382		/* dqflush unlocks dqflock */
1383		/*
1384		 * Given that dqpurge is a very rare occurrence, it is OK
1385		 * that we're holding the hashlist and mplist locks
1386		 * across the disk write. But, ... XXXsup
1387		 *
1388		 * We don't care about getting disk errors here. We need
1389		 * to purge this dquot anyway, so we go ahead regardless.
1390		 */
1391		error = xfs_qm_dqflush(dqp, SYNC_WAIT);
1392		if (error)
1393			xfs_warn(mp, "%s: dquot %p flush failed",
1394				__func__, dqp);
1395		xfs_dqflock(dqp);
1396	}
1397	ASSERT(atomic_read(&dqp->q_pincount) == 0);
1398	ASSERT(XFS_FORCED_SHUTDOWN(mp) ||
1399	       !(dqp->q_logitem.qli_item.li_flags & XFS_LI_IN_AIL));
1400
1401	list_del_init(&dqp->q_hashlist);
1402	qh->qh_version++;
1403	list_del_init(&dqp->q_mplist);
1404	mp->m_quotainfo->qi_dqreclaims++;
1405	mp->m_quotainfo->qi_dquots--;
1406	/*
1407	 * XXX Move this to the front of the freelist, if we can get the
1408	 * freelist lock.
1409	 */
1410	ASSERT(!list_empty(&dqp->q_freelist));
1411
1412	dqp->q_mount = NULL;
1413	dqp->q_hash = NULL;
1414	dqp->dq_flags = XFS_DQ_INACTIVE;
1415	memset(&dqp->q_core, 0, sizeof(dqp->q_core));
1416	xfs_dqfunlock(dqp);
1417	xfs_dqunlock(dqp);
1418	mutex_unlock(&qh->qh_lock);
1419	return (0);
1420}
1421
1422
1423/*
1424 * Give the buffer a little push if it is incore and
1425 * wait on the flush lock.
1426 */
1427void
1428xfs_qm_dqflock_pushbuf_wait(
1429	xfs_dquot_t	*dqp)
1430{
1431	xfs_mount_t	*mp = dqp->q_mount;
1432	xfs_buf_t	*bp;
1433
1434	/*
1435	 * Check to see if the dquot has been flushed delayed
1436	 * write.  If so, grab its buffer and send it
1437	 * out immediately.  We'll be able to acquire
1438	 * the flush lock when the I/O completes.
1439	 */
1440	bp = xfs_incore(mp->m_ddev_targp, dqp->q_blkno,
1441			mp->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK);
1442	if (!bp)
1443		goto out_lock;
1444
1445	if (XFS_BUF_ISDELAYWRITE(bp)) {
1446		if (xfs_buf_ispinned(bp))
1447			xfs_log_force(mp, 0);
1448		xfs_buf_delwri_promote(bp);
1449		wake_up_process(bp->b_target->bt_task);
1450	}
1451	xfs_buf_relse(bp);
1452out_lock:
1453	xfs_dqflock(dqp);
1454}
v3.15
   1/*
   2 * Copyright (c) 2000-2003 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18#include "xfs.h"
  19#include "xfs_fs.h"
  20#include "xfs_format.h"
  21#include "xfs_log_format.h"
  22#include "xfs_shared.h"
  23#include "xfs_trans_resv.h"
  24#include "xfs_bit.h"
 
 
 
  25#include "xfs_sb.h"
  26#include "xfs_ag.h"
 
 
  27#include "xfs_mount.h"
 
  28#include "xfs_inode.h"
  29#include "xfs_bmap.h"
  30#include "xfs_bmap_util.h"
  31#include "xfs_alloc.h"
  32#include "xfs_quota.h"
  33#include "xfs_error.h"
  34#include "xfs_trans.h"
 
  35#include "xfs_buf_item.h"
  36#include "xfs_trans_space.h"
  37#include "xfs_trans_priv.h"
  38#include "xfs_qm.h"
  39#include "xfs_cksum.h"
  40#include "xfs_trace.h"
  41#include "xfs_log.h"
  42#include "xfs_bmap_btree.h"
  43
  44/*
  45 * Lock order:
  46 *
  47 * ip->i_lock
  48 *   qi->qi_tree_lock
  49 *     dquot->q_qlock (xfs_dqlock() and friends)
  50 *       dquot->q_flush (xfs_dqflock() and friends)
  51 *       qi->qi_lru_lock
  52 *
  53 * If two dquots need to be locked the order is user before group/project,
  54 * otherwise by the lowest id first, see xfs_dqlock2.
  55 */
 
  56
  57#ifdef DEBUG
  58xfs_buftarg_t *xfs_dqerror_target;
  59int xfs_do_dqerror;
  60int xfs_dqreq_num;
  61int xfs_dqerror_mod = 33;
  62#endif
  63
  64struct kmem_zone		*xfs_qm_dqtrxzone;
  65static struct kmem_zone		*xfs_qm_dqzone;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  66
  67static struct lock_class_key xfs_dquot_group_class;
  68static struct lock_class_key xfs_dquot_project_class;
 
 
 
 
 
 
 
 
 
 
 
  69
  70/*
  71 * This is called to free all the memory associated with a dquot
  72 */
  73void
  74xfs_qm_dqdestroy(
  75	xfs_dquot_t	*dqp)
  76{
  77	ASSERT(list_empty(&dqp->q_lru));
  78
  79	mutex_destroy(&dqp->q_qlock);
  80	kmem_zone_free(xfs_qm_dqzone, dqp);
  81
  82	XFS_STATS_DEC(xs_qm_dquot);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  83}
  84
  85/*
  86 * If default limits are in force, push them into the dquot now.
  87 * We overwrite the dquot limits only if they are zero and this
  88 * is not the root dquot.
  89 */
  90void
  91xfs_qm_adjust_dqlimits(
  92	struct xfs_mount	*mp,
  93	struct xfs_dquot	*dq)
  94{
  95	struct xfs_quotainfo	*q = mp->m_quotainfo;
  96	struct xfs_disk_dquot	*d = &dq->q_core;
  97	int			prealloc = 0;
  98
  99	ASSERT(d->d_id);
 100
 101	if (q->qi_bsoftlimit && !d->d_blk_softlimit) {
 102		d->d_blk_softlimit = cpu_to_be64(q->qi_bsoftlimit);
 103		prealloc = 1;
 104	}
 105	if (q->qi_bhardlimit && !d->d_blk_hardlimit) {
 106		d->d_blk_hardlimit = cpu_to_be64(q->qi_bhardlimit);
 107		prealloc = 1;
 108	}
 109	if (q->qi_isoftlimit && !d->d_ino_softlimit)
 110		d->d_ino_softlimit = cpu_to_be64(q->qi_isoftlimit);
 111	if (q->qi_ihardlimit && !d->d_ino_hardlimit)
 112		d->d_ino_hardlimit = cpu_to_be64(q->qi_ihardlimit);
 113	if (q->qi_rtbsoftlimit && !d->d_rtb_softlimit)
 114		d->d_rtb_softlimit = cpu_to_be64(q->qi_rtbsoftlimit);
 115	if (q->qi_rtbhardlimit && !d->d_rtb_hardlimit)
 116		d->d_rtb_hardlimit = cpu_to_be64(q->qi_rtbhardlimit);
 117
 118	if (prealloc)
 119		xfs_dquot_set_prealloc_limits(dq);
 120}
 121
 122/*
 123 * Check the limits and timers of a dquot and start or reset timers
 124 * if necessary.
 125 * This gets called even when quota enforcement is OFF, which makes our
 126 * life a little less complicated. (We just don't reject any quota
 127 * reservations in that case, when enforcement is off).
 128 * We also return 0 as the values of the timers in Q_GETQUOTA calls, when
 129 * enforcement's off.
 130 * In contrast, warnings are a little different in that they don't
 131 * 'automatically' get started when limits get exceeded.  They do
 132 * get reset to zero, however, when we find the count to be under
 133 * the soft limit (they are only ever set non-zero via userspace).
 134 */
 135void
 136xfs_qm_adjust_dqtimers(
 137	xfs_mount_t		*mp,
 138	xfs_disk_dquot_t	*d)
 139{
 140	ASSERT(d->d_id);
 141
 142#ifdef DEBUG
 143	if (d->d_blk_hardlimit)
 144		ASSERT(be64_to_cpu(d->d_blk_softlimit) <=
 145		       be64_to_cpu(d->d_blk_hardlimit));
 146	if (d->d_ino_hardlimit)
 147		ASSERT(be64_to_cpu(d->d_ino_softlimit) <=
 148		       be64_to_cpu(d->d_ino_hardlimit));
 149	if (d->d_rtb_hardlimit)
 150		ASSERT(be64_to_cpu(d->d_rtb_softlimit) <=
 151		       be64_to_cpu(d->d_rtb_hardlimit));
 152#endif
 153
 154	if (!d->d_btimer) {
 155		if ((d->d_blk_softlimit &&
 156		     (be64_to_cpu(d->d_bcount) >
 157		      be64_to_cpu(d->d_blk_softlimit))) ||
 158		    (d->d_blk_hardlimit &&
 159		     (be64_to_cpu(d->d_bcount) >
 160		      be64_to_cpu(d->d_blk_hardlimit)))) {
 161			d->d_btimer = cpu_to_be32(get_seconds() +
 162					mp->m_quotainfo->qi_btimelimit);
 163		} else {
 164			d->d_bwarns = 0;
 165		}
 166	} else {
 167		if ((!d->d_blk_softlimit ||
 168		     (be64_to_cpu(d->d_bcount) <=
 169		      be64_to_cpu(d->d_blk_softlimit))) &&
 170		    (!d->d_blk_hardlimit ||
 171		    (be64_to_cpu(d->d_bcount) <=
 172		     be64_to_cpu(d->d_blk_hardlimit)))) {
 173			d->d_btimer = 0;
 174		}
 175	}
 176
 177	if (!d->d_itimer) {
 178		if ((d->d_ino_softlimit &&
 179		     (be64_to_cpu(d->d_icount) >
 180		      be64_to_cpu(d->d_ino_softlimit))) ||
 181		    (d->d_ino_hardlimit &&
 182		     (be64_to_cpu(d->d_icount) >
 183		      be64_to_cpu(d->d_ino_hardlimit)))) {
 184			d->d_itimer = cpu_to_be32(get_seconds() +
 185					mp->m_quotainfo->qi_itimelimit);
 186		} else {
 187			d->d_iwarns = 0;
 188		}
 189	} else {
 190		if ((!d->d_ino_softlimit ||
 191		     (be64_to_cpu(d->d_icount) <=
 192		      be64_to_cpu(d->d_ino_softlimit)))  &&
 193		    (!d->d_ino_hardlimit ||
 194		     (be64_to_cpu(d->d_icount) <=
 195		      be64_to_cpu(d->d_ino_hardlimit)))) {
 196			d->d_itimer = 0;
 197		}
 198	}
 199
 200	if (!d->d_rtbtimer) {
 201		if ((d->d_rtb_softlimit &&
 202		     (be64_to_cpu(d->d_rtbcount) >
 203		      be64_to_cpu(d->d_rtb_softlimit))) ||
 204		    (d->d_rtb_hardlimit &&
 205		     (be64_to_cpu(d->d_rtbcount) >
 206		      be64_to_cpu(d->d_rtb_hardlimit)))) {
 207			d->d_rtbtimer = cpu_to_be32(get_seconds() +
 208					mp->m_quotainfo->qi_rtbtimelimit);
 209		} else {
 210			d->d_rtbwarns = 0;
 211		}
 212	} else {
 213		if ((!d->d_rtb_softlimit ||
 214		     (be64_to_cpu(d->d_rtbcount) <=
 215		      be64_to_cpu(d->d_rtb_softlimit))) &&
 216		    (!d->d_rtb_hardlimit ||
 217		     (be64_to_cpu(d->d_rtbcount) <=
 218		      be64_to_cpu(d->d_rtb_hardlimit)))) {
 219			d->d_rtbtimer = 0;
 220		}
 221	}
 222}
 223
 224/*
 225 * initialize a buffer full of dquots and log the whole thing
 226 */
 227STATIC void
 228xfs_qm_init_dquot_blk(
 229	xfs_trans_t	*tp,
 230	xfs_mount_t	*mp,
 231	xfs_dqid_t	id,
 232	uint		type,
 233	xfs_buf_t	*bp)
 234{
 235	struct xfs_quotainfo	*q = mp->m_quotainfo;
 236	xfs_dqblk_t	*d;
 237	int		curid, i;
 238
 239	ASSERT(tp);
 240	ASSERT(xfs_buf_islocked(bp));
 241
 242	d = bp->b_addr;
 243
 244	/*
 245	 * ID of the first dquot in the block - id's are zero based.
 246	 */
 247	curid = id - (id % q->qi_dqperchunk);
 248	ASSERT(curid >= 0);
 249	memset(d, 0, BBTOB(q->qi_dqchunklen));
 250	for (i = 0; i < q->qi_dqperchunk; i++, d++, curid++) {
 251		d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
 252		d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
 253		d->dd_diskdq.d_id = cpu_to_be32(curid);
 254		d->dd_diskdq.d_flags = type;
 255		if (xfs_sb_version_hascrc(&mp->m_sb)) {
 256			uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid);
 257			xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
 258					 XFS_DQUOT_CRC_OFF);
 259		}
 260	}
 261
 262	xfs_trans_dquot_buf(tp, bp,
 263			    (type & XFS_DQ_USER ? XFS_BLF_UDQUOT_BUF :
 264			    ((type & XFS_DQ_PROJ) ? XFS_BLF_PDQUOT_BUF :
 265			     XFS_BLF_GDQUOT_BUF)));
 266	xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
 267}
 268
 269/*
 270 * Initialize the dynamic speculative preallocation thresholds. The lo/hi
 271 * watermarks correspond to the soft and hard limits by default. If a soft limit
 272 * is not specified, we use 95% of the hard limit.
 273 */
 274void
 275xfs_dquot_set_prealloc_limits(struct xfs_dquot *dqp)
 276{
 277	__uint64_t space;
 278
 279	dqp->q_prealloc_hi_wmark = be64_to_cpu(dqp->q_core.d_blk_hardlimit);
 280	dqp->q_prealloc_lo_wmark = be64_to_cpu(dqp->q_core.d_blk_softlimit);
 281	if (!dqp->q_prealloc_lo_wmark) {
 282		dqp->q_prealloc_lo_wmark = dqp->q_prealloc_hi_wmark;
 283		do_div(dqp->q_prealloc_lo_wmark, 100);
 284		dqp->q_prealloc_lo_wmark *= 95;
 285	}
 286
 287	space = dqp->q_prealloc_hi_wmark;
 288
 289	do_div(space, 100);
 290	dqp->q_low_space[XFS_QLOWSP_1_PCNT] = space;
 291	dqp->q_low_space[XFS_QLOWSP_3_PCNT] = space * 3;
 292	dqp->q_low_space[XFS_QLOWSP_5_PCNT] = space * 5;
 293}
 294
 295/*
 296 * Allocate a block and fill it with dquots.
 297 * This is called when the bmapi finds a hole.
 298 */
 299STATIC int
 300xfs_qm_dqalloc(
 301	xfs_trans_t	**tpp,
 302	xfs_mount_t	*mp,
 303	xfs_dquot_t	*dqp,
 304	xfs_inode_t	*quotip,
 305	xfs_fileoff_t	offset_fsb,
 306	xfs_buf_t	**O_bpp)
 307{
 308	xfs_fsblock_t	firstblock;
 309	xfs_bmap_free_t flist;
 310	xfs_bmbt_irec_t map;
 311	int		nmaps, error, committed;
 312	xfs_buf_t	*bp;
 313	xfs_trans_t	*tp = *tpp;
 314
 315	ASSERT(tp != NULL);
 316
 317	trace_xfs_dqalloc(dqp);
 318
 319	/*
 320	 * Initialize the bmap freelist prior to calling bmapi code.
 321	 */
 322	xfs_bmap_init(&flist, &firstblock);
 323	xfs_ilock(quotip, XFS_ILOCK_EXCL);
 324	/*
 325	 * Return if this type of quotas is turned off while we didn't
 326	 * have an inode lock
 327	 */
 328	if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
 329		xfs_iunlock(quotip, XFS_ILOCK_EXCL);
 330		return (ESRCH);
 331	}
 332
 333	xfs_trans_ijoin(tp, quotip, XFS_ILOCK_EXCL);
 334	nmaps = 1;
 335	error = xfs_bmapi_write(tp, quotip, offset_fsb,
 336				XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA,
 337				&firstblock, XFS_QM_DQALLOC_SPACE_RES(mp),
 338				&map, &nmaps, &flist);
 339	if (error)
 
 340		goto error0;
 
 341	ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB);
 342	ASSERT(nmaps == 1);
 343	ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
 344	       (map.br_startblock != HOLESTARTBLOCK));
 345
 346	/*
 347	 * Keep track of the blkno to save a lookup later
 348	 */
 349	dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
 350
 351	/* now we can just get the buffer (there's nothing to read yet) */
 352	bp = xfs_trans_get_buf(tp, mp->m_ddev_targp,
 353			       dqp->q_blkno,
 354			       mp->m_quotainfo->qi_dqchunklen,
 355			       0);
 356
 357	error = xfs_buf_geterror(bp);
 358	if (error)
 359		goto error1;
 360	bp->b_ops = &xfs_dquot_buf_ops;
 361
 362	/*
 363	 * Make a chunk of dquots out of this buffer and log
 364	 * the entire thing.
 365	 */
 366	xfs_qm_init_dquot_blk(tp, mp, be32_to_cpu(dqp->q_core.d_id),
 367			      dqp->dq_flags & XFS_DQ_ALLTYPES, bp);
 368
 369	/*
 370	 * xfs_bmap_finish() may commit the current transaction and
 371	 * start a second transaction if the freelist is not empty.
 372	 *
 373	 * Since we still want to modify this buffer, we need to
 374	 * ensure that the buffer is not released on commit of
 375	 * the first transaction and ensure the buffer is added to the
 376	 * second transaction.
 377	 *
 378	 * If there is only one transaction then don't stop the buffer
 379	 * from being released when it commits later on.
 380	 */
 381
 382	xfs_trans_bhold(tp, bp);
 383
 384	if ((error = xfs_bmap_finish(tpp, &flist, &committed))) {
 385		goto error1;
 386	}
 387
 388	if (committed) {
 389		tp = *tpp;
 390		xfs_trans_bjoin(tp, bp);
 391	} else {
 392		xfs_trans_bhold_release(tp, bp);
 393	}
 394
 395	*O_bpp = bp;
 396	return 0;
 397
 398      error1:
 399	xfs_bmap_cancel(&flist);
 400      error0:
 401	xfs_iunlock(quotip, XFS_ILOCK_EXCL);
 402
 403	return (error);
 404}
 405
 406STATIC int
 407xfs_qm_dqrepair(
 408	struct xfs_mount	*mp,
 409	struct xfs_trans	*tp,
 410	struct xfs_dquot	*dqp,
 411	xfs_dqid_t		firstid,
 412	struct xfs_buf		**bpp)
 413{
 414	int			error;
 415	struct xfs_disk_dquot	*ddq;
 416	struct xfs_dqblk	*d;
 417	int			i;
 418
 419	/*
 420	 * Read the buffer without verification so we get the corrupted
 421	 * buffer returned to us. make sure we verify it on write, though.
 422	 */
 423	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, dqp->q_blkno,
 424				   mp->m_quotainfo->qi_dqchunklen,
 425				   0, bpp, NULL);
 426
 427	if (error) {
 428		ASSERT(*bpp == NULL);
 429		return XFS_ERROR(error);
 430	}
 431	(*bpp)->b_ops = &xfs_dquot_buf_ops;
 432
 433	ASSERT(xfs_buf_islocked(*bpp));
 434	d = (struct xfs_dqblk *)(*bpp)->b_addr;
 435
 436	/* Do the actual repair of dquots in this buffer */
 437	for (i = 0; i < mp->m_quotainfo->qi_dqperchunk; i++) {
 438		ddq = &d[i].dd_diskdq;
 439		error = xfs_dqcheck(mp, ddq, firstid + i,
 440				       dqp->dq_flags & XFS_DQ_ALLTYPES,
 441				       XFS_QMOPT_DQREPAIR, "xfs_qm_dqrepair");
 442		if (error) {
 443			/* repair failed, we're screwed */
 444			xfs_trans_brelse(tp, *bpp);
 445			return XFS_ERROR(EIO);
 446		}
 447	}
 448
 449	return 0;
 450}
 451
 452/*
 453 * Maps a dquot to the buffer containing its on-disk version.
 454 * This returns a ptr to the buffer containing the on-disk dquot
 455 * in the bpp param, and a ptr to the on-disk dquot within that buffer
 456 */
 457STATIC int
 458xfs_qm_dqtobp(
 459	xfs_trans_t		**tpp,
 460	xfs_dquot_t		*dqp,
 461	xfs_disk_dquot_t	**O_ddpp,
 462	xfs_buf_t		**O_bpp,
 463	uint			flags)
 464{
 465	struct xfs_bmbt_irec	map;
 466	int			nmaps = 1, error;
 467	struct xfs_buf		*bp;
 468	struct xfs_inode	*quotip = xfs_dq_to_quota_inode(dqp);
 469	struct xfs_mount	*mp = dqp->q_mount;
 470	xfs_dqid_t		id = be32_to_cpu(dqp->q_core.d_id);
 471	struct xfs_trans	*tp = (tpp ? *tpp : NULL);
 472	uint			lock_mode;
 473
 474	dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
 475
 476	lock_mode = xfs_ilock_data_map_shared(quotip);
 477	if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
 478		/*
 479		 * Return if this type of quotas is turned off while we
 480		 * didn't have the quota inode lock.
 481		 */
 482		xfs_iunlock(quotip, lock_mode);
 483		return ESRCH;
 484	}
 485
 486	/*
 487	 * Find the block map; no allocations yet
 488	 */
 489	error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
 490			       XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
 
 491
 492	xfs_iunlock(quotip, lock_mode);
 493	if (error)
 494		return error;
 495
 496	ASSERT(nmaps == 1);
 497	ASSERT(map.br_blockcount == 1);
 498
 499	/*
 500	 * Offset of dquot in the (fixed sized) dquot chunk.
 501	 */
 502	dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) *
 503		sizeof(xfs_dqblk_t);
 504
 505	ASSERT(map.br_startblock != DELAYSTARTBLOCK);
 506	if (map.br_startblock == HOLESTARTBLOCK) {
 507		/*
 508		 * We don't allocate unless we're asked to
 509		 */
 510		if (!(flags & XFS_QMOPT_DQALLOC))
 511			return ENOENT;
 512
 513		ASSERT(tp);
 514		error = xfs_qm_dqalloc(tpp, mp, dqp, quotip,
 515					dqp->q_fileoffset, &bp);
 516		if (error)
 517			return error;
 518		tp = *tpp;
 519	} else {
 520		trace_xfs_dqtobp_read(dqp);
 521
 522		/*
 523		 * store the blkno etc so that we don't have to do the
 524		 * mapping all the time
 525		 */
 526		dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
 527
 528		error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
 529					   dqp->q_blkno,
 530					   mp->m_quotainfo->qi_dqchunklen,
 531					   0, &bp, &xfs_dquot_buf_ops);
 
 
 
 
 
 532
 533		if (error == EFSCORRUPTED && (flags & XFS_QMOPT_DQREPAIR)) {
 534			xfs_dqid_t firstid = (xfs_dqid_t)map.br_startoff *
 535						mp->m_quotainfo->qi_dqperchunk;
 536			ASSERT(bp == NULL);
 537			error = xfs_qm_dqrepair(mp, tp, dqp, firstid, &bp);
 538		}
 539
 540		if (error) {
 541			ASSERT(bp == NULL);
 542			return XFS_ERROR(error);
 
 
 
 
 
 
 
 543		}
 544	}
 545
 546	ASSERT(xfs_buf_islocked(bp));
 547	*O_bpp = bp;
 548	*O_ddpp = bp->b_addr + dqp->q_bufoffset;
 549
 550	return (0);
 551}
 552
 553
 554/*
 555 * Read in the ondisk dquot using dqtobp() then copy it to an incore version,
 556 * and release the buffer immediately.
 557 *
 558 * If XFS_QMOPT_DQALLOC is set, allocate a dquot on disk if it needed.
 559 */
 560int
 
 561xfs_qm_dqread(
 562	struct xfs_mount	*mp,
 563	xfs_dqid_t		id,
 564	uint			type,
 565	uint			flags,
 566	struct xfs_dquot	**O_dqpp)
 567{
 568	struct xfs_dquot	*dqp;
 569	struct xfs_disk_dquot	*ddqp;
 570	struct xfs_buf		*bp;
 571	struct xfs_trans	*tp = NULL;
 572	int			error;
 573	int			cancelflags = 0;
 574
 575
 576	dqp = kmem_zone_zalloc(xfs_qm_dqzone, KM_SLEEP);
 577
 578	dqp->dq_flags = type;
 579	dqp->q_core.d_id = cpu_to_be32(id);
 580	dqp->q_mount = mp;
 581	INIT_LIST_HEAD(&dqp->q_lru);
 582	mutex_init(&dqp->q_qlock);
 583	init_waitqueue_head(&dqp->q_pinwait);
 584
 585	/*
 586	 * Because we want to use a counting completion, complete
 587	 * the flush completion once to allow a single access to
 588	 * the flush completion without blocking.
 589	 */
 590	init_completion(&dqp->q_flush);
 591	complete(&dqp->q_flush);
 592
 593	/*
 594	 * Make sure group quotas have a different lock class than user
 595	 * quotas.
 596	 */
 597	switch (type) {
 598	case XFS_DQ_USER:
 599		/* uses the default lock class */
 600		break;
 601	case XFS_DQ_GROUP:
 602		lockdep_set_class(&dqp->q_qlock, &xfs_dquot_group_class);
 603		break;
 604	case XFS_DQ_PROJ:
 605		lockdep_set_class(&dqp->q_qlock, &xfs_dquot_project_class);
 606		break;
 607	default:
 608		ASSERT(0);
 609		break;
 610	}
 611
 612	XFS_STATS_INC(xs_qm_dquot);
 613
 614	trace_xfs_dqread(dqp);
 615
 616	if (flags & XFS_QMOPT_DQALLOC) {
 617		tp = xfs_trans_alloc(mp, XFS_TRANS_QM_DQALLOC);
 618		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_qm_dqalloc,
 619					  XFS_QM_DQALLOC_SPACE_RES(mp), 0);
 620		if (error)
 621			goto error1;
 622		cancelflags = XFS_TRANS_RELEASE_LOG_RES;
 623	}
 624
 625	/*
 626	 * get a pointer to the on-disk dquot and the buffer containing it
 627	 * dqp already knows its own type (GROUP/USER).
 628	 */
 629	error = xfs_qm_dqtobp(&tp, dqp, &ddqp, &bp, flags);
 630	if (error) {
 631		/*
 632		 * This can happen if quotas got turned off (ESRCH),
 633		 * or if the dquot didn't exist on disk and we ask to
 634		 * allocate (ENOENT).
 635		 */
 636		trace_xfs_dqread_fail(dqp);
 637		cancelflags |= XFS_TRANS_ABORT;
 638		goto error1;
 639	}
 
 640
 641	/* copy everything from disk dquot to the incore dquot */
 642	memcpy(&dqp->q_core, ddqp, sizeof(xfs_disk_dquot_t));
 
 643	xfs_qm_dquot_logitem_init(dqp);
 644
 645	/*
 646	 * Reservation counters are defined as reservation plus current usage
 647	 * to avoid having to add every time.
 648	 */
 649	dqp->q_res_bcount = be64_to_cpu(ddqp->d_bcount);
 650	dqp->q_res_icount = be64_to_cpu(ddqp->d_icount);
 651	dqp->q_res_rtbcount = be64_to_cpu(ddqp->d_rtbcount);
 652
 653	/* initialize the dquot speculative prealloc thresholds */
 654	xfs_dquot_set_prealloc_limits(dqp);
 655
 656	/* Mark the buf so that this will stay incore a little longer */
 657	xfs_buf_set_ref(bp, XFS_DQUOT_REF);
 658
 659	/*
 660	 * We got the buffer with a xfs_trans_read_buf() (in dqtobp())
 661	 * So we need to release with xfs_trans_brelse().
 662	 * The strategy here is identical to that of inodes; we lock
 663	 * the dquot in xfs_qm_dqget() before making it accessible to
 664	 * others. This is because dquots, like inodes, need a good level of
 665	 * concurrency, and we don't want to take locks on the entire buffers
 666	 * for dquot accesses.
 667	 * Note also that the dquot buffer may even be dirty at this point, if
 668	 * this particular dquot was repaired. We still aren't afraid to
 669	 * brelse it because we have the changes incore.
 670	 */
 671	ASSERT(xfs_buf_islocked(bp));
 672	xfs_trans_brelse(tp, bp);
 673
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 674	if (tp) {
 675		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
 676		if (error)
 677			goto error0;
 678	}
 679
 680	*O_dqpp = dqp;
 681	return error;
 682
 683error1:
 
 684	if (tp)
 685		xfs_trans_cancel(tp, cancelflags);
 686error0:
 687	xfs_qm_dqdestroy(dqp);
 688	*O_dqpp = NULL;
 689	return error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 690}
 691
 692/*
 693 * Given the file system, inode OR id, and type (UDQUOT/GDQUOT), return a
 694 * a locked dquot, doing an allocation (if requested) as needed.
 695 * When both an inode and an id are given, the inode's id takes precedence.
 696 * That is, if the id changes while we don't hold the ilock inside this
 697 * function, the new dquot is returned, not necessarily the one requested
 698 * in the id argument.
 699 */
 700int
 701xfs_qm_dqget(
 702	xfs_mount_t	*mp,
 703	xfs_inode_t	*ip,	  /* locked inode (optional) */
 704	xfs_dqid_t	id,	  /* uid/projid/gid depending on type */
 705	uint		type,	  /* XFS_DQ_USER/XFS_DQ_PROJ/XFS_DQ_GROUP */
 706	uint		flags,	  /* DQALLOC, DQSUSER, DQREPAIR, DOWARN */
 707	xfs_dquot_t	**O_dqpp) /* OUT : locked incore dquot */
 708{
 709	struct xfs_quotainfo	*qi = mp->m_quotainfo;
 710	struct radix_tree_root *tree = xfs_dquot_tree(qi, type);
 711	struct xfs_dquot	*dqp;
 712	int			error;
 713
 714	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
 715	if ((! XFS_IS_UQUOTA_ON(mp) && type == XFS_DQ_USER) ||
 716	    (! XFS_IS_PQUOTA_ON(mp) && type == XFS_DQ_PROJ) ||
 717	    (! XFS_IS_GQUOTA_ON(mp) && type == XFS_DQ_GROUP)) {
 718		return (ESRCH);
 719	}
 
 720
 721#ifdef DEBUG
 722	if (xfs_do_dqerror) {
 723		if ((xfs_dqerror_target == mp->m_ddev_targp) &&
 724		    (xfs_dqreq_num++ % xfs_dqerror_mod) == 0) {
 725			xfs_debug(mp, "Returning error in dqget");
 726			return (EIO);
 727		}
 728	}
 
 
 
 729
 
 730	ASSERT(type == XFS_DQ_USER ||
 731	       type == XFS_DQ_PROJ ||
 732	       type == XFS_DQ_GROUP);
 733	if (ip) {
 734		ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 735		ASSERT(xfs_inode_dquot(ip, type) == NULL);
 
 
 
 736	}
 737#endif
 
 738
 739restart:
 740	mutex_lock(&qi->qi_tree_lock);
 741	dqp = radix_tree_lookup(tree, id);
 742	if (dqp) {
 743		xfs_dqlock(dqp);
 744		if (dqp->dq_flags & XFS_DQ_FREEING) {
 745			xfs_dqunlock(dqp);
 746			mutex_unlock(&qi->qi_tree_lock);
 747			trace_xfs_dqget_freeing(dqp);
 748			delay(1);
 749			goto restart;
 750		}
 751
 752		dqp->q_nrefs++;
 753		mutex_unlock(&qi->qi_tree_lock);
 754
 755		trace_xfs_dqget_hit(dqp);
 756		XFS_STATS_INC(xs_qm_dqcachehits);
 757		*O_dqpp = dqp;
 758		return 0;
 759	}
 760	mutex_unlock(&qi->qi_tree_lock);
 761	XFS_STATS_INC(xs_qm_dqcachemisses);
 762
 763	/*
 764	 * Dquot cache miss. We don't want to keep the inode lock across
 765	 * a (potential) disk read. Also we don't want to deal with the lock
 766	 * ordering between quotainode and this inode. OTOH, dropping the inode
 767	 * lock here means dealing with a chown that can happen before
 768	 * we re-acquire the lock.
 769	 */
 770	if (ip)
 771		xfs_iunlock(ip, XFS_ILOCK_EXCL);
 
 
 
 
 
 
 772
 773	error = xfs_qm_dqread(mp, id, type, flags, &dqp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 774
 775	if (ip)
 
 
 
 776		xfs_ilock(ip, XFS_ILOCK_EXCL);
 777
 778	if (error)
 779		return error;
 780
 781	if (ip) {
 782		/*
 783		 * A dquot could be attached to this inode by now, since
 784		 * we had dropped the ilock.
 785		 */
 786		if (xfs_this_quota_on(mp, type)) {
 787			struct xfs_dquot	*dqp1;
 788
 789			dqp1 = xfs_inode_dquot(ip, type);
 790			if (dqp1) {
 
 
 791				xfs_qm_dqdestroy(dqp);
 792				dqp = dqp1;
 793				xfs_dqlock(dqp);
 794				goto dqret;
 795			}
 796		} else {
 797			/* inode stays locked on return */
 798			xfs_qm_dqdestroy(dqp);
 799			return XFS_ERROR(ESRCH);
 
 
 
 
 
 
 
 
 800		}
 801	}
 802
 803	mutex_lock(&qi->qi_tree_lock);
 804	error = -radix_tree_insert(tree, id, dqp);
 805	if (unlikely(error)) {
 806		WARN_ON(error != EEXIST);
 807
 
 808		/*
 809		 * Duplicate found. Just throw away the new dquot and start
 810		 * over.
 
 
 
 811		 */
 812		mutex_unlock(&qi->qi_tree_lock);
 813		trace_xfs_dqget_dup(dqp);
 814		xfs_qm_dqdestroy(dqp);
 815		XFS_STATS_INC(xs_qm_dquot_dups);
 816		goto restart;
 
 
 
 
 
 
 817	}
 818
 819	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 820	 * We return a locked dquot to the caller, with a reference taken
 821	 */
 822	xfs_dqlock(dqp);
 823	dqp->q_nrefs = 1;
 824
 825	qi->qi_dquots++;
 826	mutex_unlock(&qi->qi_tree_lock);
 827
 
 828 dqret:
 829	ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL));
 830	trace_xfs_dqget_miss(dqp);
 831	*O_dqpp = dqp;
 832	return (0);
 833}
 834
 835
 836STATIC void
 837xfs_qm_dqput_final(
 838	struct xfs_dquot	*dqp)
 
 
 
 
 
 
 839{
 840	struct xfs_quotainfo	*qi = dqp->q_mount->m_quotainfo;
 841	struct xfs_dquot	*gdqp;
 842	struct xfs_dquot	*pdqp;
 843
 844	trace_xfs_dqput_free(dqp);
 
 845
 846	if (list_lru_add(&qi->qi_lru, &dqp->q_lru))
 847		XFS_STATS_INC(xs_qm_dquot_unused);
 848
 849	/*
 850	 * If we just added a udquot to the freelist, then we want to release
 851	 * the gdquot/pdquot reference that it (probably) has. Otherwise it'll
 852	 * keep the gdquot/pdquot from getting reclaimed.
 853	 */
 854	gdqp = dqp->q_gdquot;
 855	if (gdqp) {
 856		xfs_dqlock(gdqp);
 857		dqp->q_gdquot = NULL;
 858	}
 859
 860	pdqp = dqp->q_pdquot;
 861	if (pdqp) {
 862		xfs_dqlock(pdqp);
 863		dqp->q_pdquot = NULL;
 864	}
 865	xfs_dqunlock(dqp);
 866
 867	/*
 868	 * If we had a group/project quota hint, release it now.
 
 869	 */
 870	if (gdqp)
 871		xfs_qm_dqput(gdqp);
 872	if (pdqp)
 873		xfs_qm_dqput(pdqp);
 874}
 
 875
 876/*
 877 * Release a reference to the dquot (decrement ref-count) and unlock it.
 878 *
 879 * If there is a group quota attached to this dquot, carefully release that
 880 * too without tripping over deadlocks'n'stuff.
 881 */
 882void
 883xfs_qm_dqput(
 884	struct xfs_dquot	*dqp)
 885{
 886	ASSERT(dqp->q_nrefs > 0);
 887	ASSERT(XFS_DQ_IS_LOCKED(dqp));
 888
 889	trace_xfs_dqput(dqp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 890
 891	if (--dqp->q_nrefs > 0)
 892		xfs_dqunlock(dqp);
 893	else
 894		xfs_qm_dqput_final(dqp);
 
 
 
 
 
 895}
 896
 897/*
 898 * Release a dquot. Flush it if dirty, then dqput() it.
 899 * dquot must not be locked.
 900 */
 901void
 902xfs_qm_dqrele(
 903	xfs_dquot_t	*dqp)
 904{
 905	if (!dqp)
 906		return;
 907
 908	trace_xfs_dqrele(dqp);
 909
 910	xfs_dqlock(dqp);
 911	/*
 912	 * We don't care to flush it if the dquot is dirty here.
 913	 * That will create stutters that we want to avoid.
 914	 * Instead we do a delayed write when we try to reclaim
 915	 * a dirty dquot. Also xfs_sync will take part of the burden...
 916	 */
 917	xfs_qm_dqput(dqp);
 918}
 919
 920/*
 921 * This is the dquot flushing I/O completion routine.  It is called
 922 * from interrupt level when the buffer containing the dquot is
 923 * flushed to disk.  It is responsible for removing the dquot logitem
 924 * from the AIL if it has not been re-logged, and unlocking the dquot's
 925 * flush lock. This behavior is very similar to that of inodes..
 926 */
 927STATIC void
 928xfs_qm_dqflush_done(
 929	struct xfs_buf		*bp,
 930	struct xfs_log_item	*lip)
 931{
 932	xfs_dq_logitem_t	*qip = (struct xfs_dq_logitem *)lip;
 933	xfs_dquot_t		*dqp = qip->qli_dquot;
 934	struct xfs_ail		*ailp = lip->li_ailp;
 935
 936	/*
 937	 * We only want to pull the item from the AIL if its
 938	 * location in the log has not changed since we started the flush.
 939	 * Thus, we only bother if the dquot's lsn has
 940	 * not changed. First we check the lsn outside the lock
 941	 * since it's cheaper, and then we recheck while
 942	 * holding the lock before removing the dquot from the AIL.
 943	 */
 944	if ((lip->li_flags & XFS_LI_IN_AIL) &&
 945	    lip->li_lsn == qip->qli_flush_lsn) {
 946
 947		/* xfs_trans_ail_delete() drops the AIL lock. */
 948		spin_lock(&ailp->xa_lock);
 949		if (lip->li_lsn == qip->qli_flush_lsn)
 950			xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE);
 951		else
 952			spin_unlock(&ailp->xa_lock);
 953	}
 954
 955	/*
 956	 * Release the dq's flush lock since we're done with it.
 957	 */
 958	xfs_dqfunlock(dqp);
 959}
 960
 961/*
 962 * Write a modified dquot to disk.
 963 * The dquot must be locked and the flush lock too taken by caller.
 964 * The flush lock will not be unlocked until the dquot reaches the disk,
 965 * but the dquot is free to be unlocked and modified by the caller
 966 * in the interim. Dquot is still locked on return. This behavior is
 967 * identical to that of inodes.
 968 */
 969int
 970xfs_qm_dqflush(
 971	struct xfs_dquot	*dqp,
 972	struct xfs_buf		**bpp)
 973{
 974	struct xfs_mount	*mp = dqp->q_mount;
 975	struct xfs_buf		*bp;
 976	struct xfs_disk_dquot	*ddqp;
 977	int			error;
 978
 979	ASSERT(XFS_DQ_IS_LOCKED(dqp));
 980	ASSERT(!completion_done(&dqp->q_flush));
 981
 982	trace_xfs_dqflush(dqp);
 983
 984	*bpp = NULL;
 985
 
 
 
 
 
 
 986	xfs_qm_dqunpin_wait(dqp);
 987
 988	/*
 989	 * This may have been unpinned because the filesystem is shutting
 990	 * down forcibly. If that's the case we must not write this dquot
 991	 * to disk, because the log record didn't make it to disk.
 992	 *
 993	 * We also have to remove the log item from the AIL in this case,
 994	 * as we wait for an emptry AIL as part of the unmount process.
 995	 */
 996	if (XFS_FORCED_SHUTDOWN(mp)) {
 997		struct xfs_log_item	*lip = &dqp->q_logitem.qli_item;
 998		dqp->dq_flags &= ~XFS_DQ_DIRTY;
 999
1000		spin_lock(&mp->m_ail->xa_lock);
1001		if (lip->li_flags & XFS_LI_IN_AIL)
1002			xfs_trans_ail_delete(mp->m_ail, lip,
1003					     SHUTDOWN_CORRUPT_INCORE);
1004		else
1005			spin_unlock(&mp->m_ail->xa_lock);
1006		error = XFS_ERROR(EIO);
1007		goto out_unlock;
1008	}
1009
1010	/*
1011	 * Get the buffer containing the on-disk dquot
1012	 */
1013	error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno,
1014				   mp->m_quotainfo->qi_dqchunklen, 0, &bp, NULL);
1015	if (error)
1016		goto out_unlock;
 
 
 
1017
1018	/*
1019	 * Calculate the location of the dquot inside the buffer.
1020	 */
1021	ddqp = bp->b_addr + dqp->q_bufoffset;
1022
1023	/*
1024	 * A simple sanity check in case we got a corrupted dquot..
1025	 */
1026	error = xfs_dqcheck(mp, &dqp->q_core, be32_to_cpu(ddqp->d_id), 0,
1027			   XFS_QMOPT_DOWARN, "dqflush (incore copy)");
1028	if (error) {
1029		xfs_buf_relse(bp);
1030		xfs_dqfunlock(dqp);
1031		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1032		return XFS_ERROR(EIO);
1033	}
1034
1035	/* This is the only portion of data that needs to persist */
1036	memcpy(ddqp, &dqp->q_core, sizeof(xfs_disk_dquot_t));
1037
1038	/*
1039	 * Clear the dirty field and remember the flush lsn for later use.
1040	 */
1041	dqp->dq_flags &= ~XFS_DQ_DIRTY;
1042
1043	xfs_trans_ail_copy_lsn(mp->m_ail, &dqp->q_logitem.qli_flush_lsn,
1044					&dqp->q_logitem.qli_item.li_lsn);
1045
1046	/*
1047	 * copy the lsn into the on-disk dquot now while we have the in memory
1048	 * dquot here. This can't be done later in the write verifier as we
1049	 * can't get access to the log item at that point in time.
1050	 *
1051	 * We also calculate the CRC here so that the on-disk dquot in the
1052	 * buffer always has a valid CRC. This ensures there is no possibility
1053	 * of a dquot without an up-to-date CRC getting to disk.
1054	 */
1055	if (xfs_sb_version_hascrc(&mp->m_sb)) {
1056		struct xfs_dqblk *dqb = (struct xfs_dqblk *)ddqp;
1057
1058		dqb->dd_lsn = cpu_to_be64(dqp->q_logitem.qli_item.li_lsn);
1059		xfs_update_cksum((char *)dqb, sizeof(struct xfs_dqblk),
1060				 XFS_DQUOT_CRC_OFF);
1061	}
1062
1063	/*
1064	 * Attach an iodone routine so that we can remove this dquot from the
1065	 * AIL and release the flush lock once the dquot is synced to disk.
1066	 */
1067	xfs_buf_attach_iodone(bp, xfs_qm_dqflush_done,
1068				  &dqp->q_logitem.qli_item);
1069
1070	/*
1071	 * If the buffer is pinned then push on the log so we won't
1072	 * get stuck waiting in the write for too long.
1073	 */
1074	if (xfs_buf_ispinned(bp)) {
1075		trace_xfs_dqflush_force(dqp);
1076		xfs_log_force(mp, 0);
1077	}
1078
 
 
 
 
 
1079	trace_xfs_dqflush_done(dqp);
1080	*bpp = bp;
1081	return 0;
1082
1083out_unlock:
1084	xfs_dqfunlock(dqp);
1085	return XFS_ERROR(EIO);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1086}
1087
1088/*
1089 * Lock two xfs_dquot structures.
1090 *
1091 * To avoid deadlocks we always lock the quota structure with
1092 * the lowerd id first.
1093 */
1094void
1095xfs_dqlock2(
1096	xfs_dquot_t	*d1,
1097	xfs_dquot_t	*d2)
1098{
1099	if (d1 && d2) {
1100		ASSERT(d1 != d2);
1101		if (be32_to_cpu(d1->q_core.d_id) >
1102		    be32_to_cpu(d2->q_core.d_id)) {
1103			mutex_lock(&d2->q_qlock);
1104			mutex_lock_nested(&d1->q_qlock, XFS_QLOCK_NESTED);
1105		} else {
1106			mutex_lock(&d1->q_qlock);
1107			mutex_lock_nested(&d2->q_qlock, XFS_QLOCK_NESTED);
1108		}
1109	} else if (d1) {
1110		mutex_lock(&d1->q_qlock);
1111	} else if (d2) {
1112		mutex_lock(&d2->q_qlock);
1113	}
1114}
1115
1116int __init
1117xfs_qm_init(void)
 
 
 
 
 
 
 
 
 
 
 
 
1118{
1119	xfs_qm_dqzone =
1120		kmem_zone_init(sizeof(struct xfs_dquot), "xfs_dquot");
1121	if (!xfs_qm_dqzone)
1122		goto out;
1123
1124	xfs_qm_dqtrxzone =
1125		kmem_zone_init(sizeof(struct xfs_dquot_acct), "xfs_dqtrx");
1126	if (!xfs_qm_dqtrxzone)
1127		goto out_free_dqzone;
 
 
 
 
 
 
 
 
 
 
 
1128
1129	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1130
1131out_free_dqzone:
1132	kmem_zone_destroy(xfs_qm_dqzone);
1133out:
1134	return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1135}
1136
 
 
 
 
 
1137void
1138xfs_qm_exit(void)
 
1139{
1140	kmem_zone_destroy(xfs_qm_dqtrxzone);
1141	kmem_zone_destroy(xfs_qm_dqzone);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1142}