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v4.17
 
   1/*
   2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   3 * Copyright (C) 2010 Red Hat, Inc.
   4 * All Rights Reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it would be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write the Free Software Foundation,
  17 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18 */
  19#include "xfs.h"
  20#include "xfs_fs.h"
  21#include "xfs_shared.h"
  22#include "xfs_format.h"
  23#include "xfs_log_format.h"
  24#include "xfs_trans_resv.h"
  25#include "xfs_mount.h"
  26#include "xfs_inode.h"
  27#include "xfs_extent_busy.h"
  28#include "xfs_quota.h"
  29#include "xfs_trans.h"
  30#include "xfs_trans_priv.h"
  31#include "xfs_log.h"
  32#include "xfs_trace.h"
  33#include "xfs_error.h"
 
  34
  35kmem_zone_t	*xfs_trans_zone;
  36kmem_zone_t	*xfs_log_item_desc_zone;
  37
  38#if defined(CONFIG_TRACEPOINTS)
  39static void
  40xfs_trans_trace_reservations(
  41	struct xfs_mount	*mp)
  42{
  43	struct xfs_trans_res	resv;
  44	struct xfs_trans_res	*res;
  45	struct xfs_trans_res	*end_res;
  46	int			i;
  47
  48	res = (struct xfs_trans_res *)M_RES(mp);
  49	end_res = (struct xfs_trans_res *)(M_RES(mp) + 1);
  50	for (i = 0; res < end_res; i++, res++)
  51		trace_xfs_trans_resv_calc(mp, i, res);
  52	xfs_log_get_max_trans_res(mp, &resv);
  53	trace_xfs_trans_resv_calc(mp, -1, &resv);
  54}
  55#else
  56# define xfs_trans_trace_reservations(mp)
  57#endif
  58
  59/*
  60 * Initialize the precomputed transaction reservation values
  61 * in the mount structure.
  62 */
  63void
  64xfs_trans_init(
  65	struct xfs_mount	*mp)
  66{
  67	xfs_trans_resv_calc(mp, M_RES(mp));
  68	xfs_trans_trace_reservations(mp);
  69}
  70
  71/*
  72 * Free the transaction structure.  If there is more clean up
  73 * to do when the structure is freed, add it here.
  74 */
  75STATIC void
  76xfs_trans_free(
  77	struct xfs_trans	*tp)
  78{
  79	xfs_extent_busy_sort(&tp->t_busy);
  80	xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false);
  81
 
  82	atomic_dec(&tp->t_mountp->m_active_trans);
  83	if (!(tp->t_flags & XFS_TRANS_NO_WRITECOUNT))
  84		sb_end_intwrite(tp->t_mountp->m_super);
  85	xfs_trans_free_dqinfo(tp);
  86	kmem_zone_free(xfs_trans_zone, tp);
  87}
  88
  89/*
  90 * This is called to create a new transaction which will share the
  91 * permanent log reservation of the given transaction.  The remaining
  92 * unused block and rt extent reservations are also inherited.  This
  93 * implies that the original transaction is no longer allowed to allocate
  94 * blocks.  Locks and log items, however, are no inherited.  They must
  95 * be added to the new transaction explicitly.
  96 */
  97STATIC xfs_trans_t *
  98xfs_trans_dup(
  99	xfs_trans_t	*tp)
 100{
 101	xfs_trans_t	*ntp;
 
 
 102
 103	ntp = kmem_zone_zalloc(xfs_trans_zone, KM_SLEEP);
 104
 105	/*
 106	 * Initialize the new transaction structure.
 107	 */
 108	ntp->t_magic = XFS_TRANS_HEADER_MAGIC;
 109	ntp->t_mountp = tp->t_mountp;
 110	INIT_LIST_HEAD(&ntp->t_items);
 111	INIT_LIST_HEAD(&ntp->t_busy);
 
 
 112
 113	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
 114	ASSERT(tp->t_ticket != NULL);
 115
 116	ntp->t_flags = XFS_TRANS_PERM_LOG_RES |
 117		       (tp->t_flags & XFS_TRANS_RESERVE) |
 118		       (tp->t_flags & XFS_TRANS_NO_WRITECOUNT);
 119	/* We gave our writer reference to the new transaction */
 120	tp->t_flags |= XFS_TRANS_NO_WRITECOUNT;
 121	ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
 122
 123	ASSERT(tp->t_blk_res >= tp->t_blk_res_used);
 124	ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
 125	tp->t_blk_res = tp->t_blk_res_used;
 126
 127	ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used;
 128	tp->t_rtx_res = tp->t_rtx_res_used;
 129	ntp->t_pflags = tp->t_pflags;
 130
 
 
 
 131	xfs_trans_dup_dqinfo(tp, ntp);
 132
 133	atomic_inc(&tp->t_mountp->m_active_trans);
 134	return ntp;
 135}
 136
 137/*
 138 * This is called to reserve free disk blocks and log space for the
 139 * given transaction.  This must be done before allocating any resources
 140 * within the transaction.
 141 *
 142 * This will return ENOSPC if there are not enough blocks available.
 143 * It will sleep waiting for available log space.
 144 * The only valid value for the flags parameter is XFS_RES_LOG_PERM, which
 145 * is used by long running transactions.  If any one of the reservations
 146 * fails then they will all be backed out.
 147 *
 148 * This does not do quota reservations. That typically is done by the
 149 * caller afterwards.
 150 */
 151static int
 152xfs_trans_reserve(
 153	struct xfs_trans	*tp,
 154	struct xfs_trans_res	*resp,
 155	uint			blocks,
 156	uint			rtextents)
 157{
 158	int		error = 0;
 159	bool		rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
 160
 161	/* Mark this thread as being in a transaction */
 162	current_set_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 163
 164	/*
 165	 * Attempt to reserve the needed disk blocks by decrementing
 166	 * the number needed from the number available.  This will
 167	 * fail if the count would go below zero.
 168	 */
 169	if (blocks > 0) {
 170		error = xfs_mod_fdblocks(tp->t_mountp, -((int64_t)blocks), rsvd);
 171		if (error != 0) {
 172			current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 173			return -ENOSPC;
 174		}
 175		tp->t_blk_res += blocks;
 176	}
 177
 178	/*
 179	 * Reserve the log space needed for this transaction.
 180	 */
 181	if (resp->tr_logres > 0) {
 182		bool	permanent = false;
 183
 184		ASSERT(tp->t_log_res == 0 ||
 185		       tp->t_log_res == resp->tr_logres);
 186		ASSERT(tp->t_log_count == 0 ||
 187		       tp->t_log_count == resp->tr_logcount);
 188
 189		if (resp->tr_logflags & XFS_TRANS_PERM_LOG_RES) {
 190			tp->t_flags |= XFS_TRANS_PERM_LOG_RES;
 191			permanent = true;
 192		} else {
 193			ASSERT(tp->t_ticket == NULL);
 194			ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
 195		}
 196
 197		if (tp->t_ticket != NULL) {
 198			ASSERT(resp->tr_logflags & XFS_TRANS_PERM_LOG_RES);
 199			error = xfs_log_regrant(tp->t_mountp, tp->t_ticket);
 200		} else {
 201			error = xfs_log_reserve(tp->t_mountp,
 202						resp->tr_logres,
 203						resp->tr_logcount,
 204						&tp->t_ticket, XFS_TRANSACTION,
 205						permanent);
 206		}
 207
 208		if (error)
 209			goto undo_blocks;
 210
 211		tp->t_log_res = resp->tr_logres;
 212		tp->t_log_count = resp->tr_logcount;
 213	}
 214
 215	/*
 216	 * Attempt to reserve the needed realtime extents by decrementing
 217	 * the number needed from the number available.  This will
 218	 * fail if the count would go below zero.
 219	 */
 220	if (rtextents > 0) {
 221		error = xfs_mod_frextents(tp->t_mountp, -((int64_t)rtextents));
 222		if (error) {
 223			error = -ENOSPC;
 224			goto undo_log;
 225		}
 226		tp->t_rtx_res += rtextents;
 227	}
 228
 229	return 0;
 230
 231	/*
 232	 * Error cases jump to one of these labels to undo any
 233	 * reservations which have already been performed.
 234	 */
 235undo_log:
 236	if (resp->tr_logres > 0) {
 237		xfs_log_done(tp->t_mountp, tp->t_ticket, NULL, false);
 238		tp->t_ticket = NULL;
 239		tp->t_log_res = 0;
 240		tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES;
 241	}
 242
 243undo_blocks:
 244	if (blocks > 0) {
 245		xfs_mod_fdblocks(tp->t_mountp, (int64_t)blocks, rsvd);
 246		tp->t_blk_res = 0;
 247	}
 248
 249	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 250
 251	return error;
 252}
 253
 254int
 255xfs_trans_alloc(
 256	struct xfs_mount	*mp,
 257	struct xfs_trans_res	*resp,
 258	uint			blocks,
 259	uint			rtextents,
 260	uint			flags,
 261	struct xfs_trans	**tpp)
 262{
 263	struct xfs_trans	*tp;
 264	int			error;
 265
 
 
 
 
 
 
 266	if (!(flags & XFS_TRANS_NO_WRITECOUNT))
 267		sb_start_intwrite(mp->m_super);
 268
 269	WARN_ON(mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE);
 
 
 
 
 
 270	atomic_inc(&mp->m_active_trans);
 271
 272	tp = kmem_zone_zalloc(xfs_trans_zone,
 273		(flags & XFS_TRANS_NOFS) ? KM_NOFS : KM_SLEEP);
 274	tp->t_magic = XFS_TRANS_HEADER_MAGIC;
 275	tp->t_flags = flags;
 276	tp->t_mountp = mp;
 277	INIT_LIST_HEAD(&tp->t_items);
 278	INIT_LIST_HEAD(&tp->t_busy);
 
 
 279
 280	error = xfs_trans_reserve(tp, resp, blocks, rtextents);
 281	if (error) {
 282		xfs_trans_cancel(tp);
 283		return error;
 284	}
 285
 
 
 286	*tpp = tp;
 287	return 0;
 288}
 289
 290/*
 291 * Create an empty transaction with no reservation.  This is a defensive
 292 * mechanism for routines that query metadata without actually modifying
 293 * them -- if the metadata being queried is somehow cross-linked (think a
 294 * btree block pointer that points higher in the tree), we risk deadlock.
 295 * However, blocks grabbed as part of a transaction can be re-grabbed.
 296 * The verifiers will notice the corrupt block and the operation will fail
 297 * back to userspace without deadlocking.
 298 *
 299 * Note the zero-length reservation; this transaction MUST be cancelled
 300 * without any dirty data.
 301 */
 302int
 303xfs_trans_alloc_empty(
 304	struct xfs_mount		*mp,
 305	struct xfs_trans		**tpp)
 306{
 307	struct xfs_trans_res		resv = {0};
 308
 309	return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp);
 310}
 311
 312/*
 313 * Record the indicated change to the given field for application
 314 * to the file system's superblock when the transaction commits.
 315 * For now, just store the change in the transaction structure.
 316 *
 317 * Mark the transaction structure to indicate that the superblock
 318 * needs to be updated before committing.
 319 *
 320 * Because we may not be keeping track of allocated/free inodes and
 321 * used filesystem blocks in the superblock, we do not mark the
 322 * superblock dirty in this transaction if we modify these fields.
 323 * We still need to update the transaction deltas so that they get
 324 * applied to the incore superblock, but we don't want them to
 325 * cause the superblock to get locked and logged if these are the
 326 * only fields in the superblock that the transaction modifies.
 327 */
 328void
 329xfs_trans_mod_sb(
 330	xfs_trans_t	*tp,
 331	uint		field,
 332	int64_t		delta)
 333{
 334	uint32_t	flags = (XFS_TRANS_DIRTY|XFS_TRANS_SB_DIRTY);
 335	xfs_mount_t	*mp = tp->t_mountp;
 336
 337	switch (field) {
 338	case XFS_TRANS_SB_ICOUNT:
 339		tp->t_icount_delta += delta;
 340		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 341			flags &= ~XFS_TRANS_SB_DIRTY;
 342		break;
 343	case XFS_TRANS_SB_IFREE:
 344		tp->t_ifree_delta += delta;
 345		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 346			flags &= ~XFS_TRANS_SB_DIRTY;
 347		break;
 348	case XFS_TRANS_SB_FDBLOCKS:
 349		/*
 350		 * Track the number of blocks allocated in the transaction.
 351		 * Make sure it does not exceed the number reserved. If so,
 352		 * shutdown as this can lead to accounting inconsistency.
 353		 */
 354		if (delta < 0) {
 355			tp->t_blk_res_used += (uint)-delta;
 356			if (tp->t_blk_res_used > tp->t_blk_res)
 357				xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 358		}
 359		tp->t_fdblocks_delta += delta;
 360		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 361			flags &= ~XFS_TRANS_SB_DIRTY;
 362		break;
 363	case XFS_TRANS_SB_RES_FDBLOCKS:
 364		/*
 365		 * The allocation has already been applied to the
 366		 * in-core superblock's counter.  This should only
 367		 * be applied to the on-disk superblock.
 368		 */
 369		tp->t_res_fdblocks_delta += delta;
 370		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 371			flags &= ~XFS_TRANS_SB_DIRTY;
 372		break;
 373	case XFS_TRANS_SB_FREXTENTS:
 374		/*
 375		 * Track the number of blocks allocated in the
 376		 * transaction.  Make sure it does not exceed the
 377		 * number reserved.
 378		 */
 379		if (delta < 0) {
 380			tp->t_rtx_res_used += (uint)-delta;
 381			ASSERT(tp->t_rtx_res_used <= tp->t_rtx_res);
 382		}
 383		tp->t_frextents_delta += delta;
 384		break;
 385	case XFS_TRANS_SB_RES_FREXTENTS:
 386		/*
 387		 * The allocation has already been applied to the
 388		 * in-core superblock's counter.  This should only
 389		 * be applied to the on-disk superblock.
 390		 */
 391		ASSERT(delta < 0);
 392		tp->t_res_frextents_delta += delta;
 393		break;
 394	case XFS_TRANS_SB_DBLOCKS:
 395		ASSERT(delta > 0);
 396		tp->t_dblocks_delta += delta;
 397		break;
 398	case XFS_TRANS_SB_AGCOUNT:
 399		ASSERT(delta > 0);
 400		tp->t_agcount_delta += delta;
 401		break;
 402	case XFS_TRANS_SB_IMAXPCT:
 403		tp->t_imaxpct_delta += delta;
 404		break;
 405	case XFS_TRANS_SB_REXTSIZE:
 406		tp->t_rextsize_delta += delta;
 407		break;
 408	case XFS_TRANS_SB_RBMBLOCKS:
 409		tp->t_rbmblocks_delta += delta;
 410		break;
 411	case XFS_TRANS_SB_RBLOCKS:
 412		tp->t_rblocks_delta += delta;
 413		break;
 414	case XFS_TRANS_SB_REXTENTS:
 415		tp->t_rextents_delta += delta;
 416		break;
 417	case XFS_TRANS_SB_REXTSLOG:
 418		tp->t_rextslog_delta += delta;
 419		break;
 420	default:
 421		ASSERT(0);
 422		return;
 423	}
 424
 425	tp->t_flags |= flags;
 426}
 427
 428/*
 429 * xfs_trans_apply_sb_deltas() is called from the commit code
 430 * to bring the superblock buffer into the current transaction
 431 * and modify it as requested by earlier calls to xfs_trans_mod_sb().
 432 *
 433 * For now we just look at each field allowed to change and change
 434 * it if necessary.
 435 */
 436STATIC void
 437xfs_trans_apply_sb_deltas(
 438	xfs_trans_t	*tp)
 439{
 440	xfs_dsb_t	*sbp;
 441	xfs_buf_t	*bp;
 442	int		whole = 0;
 443
 444	bp = xfs_trans_getsb(tp, tp->t_mountp, 0);
 445	sbp = XFS_BUF_TO_SBP(bp);
 446
 447	/*
 448	 * Check that superblock mods match the mods made to AGF counters.
 449	 */
 450	ASSERT((tp->t_fdblocks_delta + tp->t_res_fdblocks_delta) ==
 451	       (tp->t_ag_freeblks_delta + tp->t_ag_flist_delta +
 452		tp->t_ag_btree_delta));
 453
 454	/*
 455	 * Only update the superblock counters if we are logging them
 456	 */
 457	if (!xfs_sb_version_haslazysbcount(&(tp->t_mountp->m_sb))) {
 458		if (tp->t_icount_delta)
 459			be64_add_cpu(&sbp->sb_icount, tp->t_icount_delta);
 460		if (tp->t_ifree_delta)
 461			be64_add_cpu(&sbp->sb_ifree, tp->t_ifree_delta);
 462		if (tp->t_fdblocks_delta)
 463			be64_add_cpu(&sbp->sb_fdblocks, tp->t_fdblocks_delta);
 464		if (tp->t_res_fdblocks_delta)
 465			be64_add_cpu(&sbp->sb_fdblocks, tp->t_res_fdblocks_delta);
 466	}
 467
 468	if (tp->t_frextents_delta)
 469		be64_add_cpu(&sbp->sb_frextents, tp->t_frextents_delta);
 470	if (tp->t_res_frextents_delta)
 471		be64_add_cpu(&sbp->sb_frextents, tp->t_res_frextents_delta);
 472
 473	if (tp->t_dblocks_delta) {
 474		be64_add_cpu(&sbp->sb_dblocks, tp->t_dblocks_delta);
 475		whole = 1;
 476	}
 477	if (tp->t_agcount_delta) {
 478		be32_add_cpu(&sbp->sb_agcount, tp->t_agcount_delta);
 479		whole = 1;
 480	}
 481	if (tp->t_imaxpct_delta) {
 482		sbp->sb_imax_pct += tp->t_imaxpct_delta;
 483		whole = 1;
 484	}
 485	if (tp->t_rextsize_delta) {
 486		be32_add_cpu(&sbp->sb_rextsize, tp->t_rextsize_delta);
 487		whole = 1;
 488	}
 489	if (tp->t_rbmblocks_delta) {
 490		be32_add_cpu(&sbp->sb_rbmblocks, tp->t_rbmblocks_delta);
 491		whole = 1;
 492	}
 493	if (tp->t_rblocks_delta) {
 494		be64_add_cpu(&sbp->sb_rblocks, tp->t_rblocks_delta);
 495		whole = 1;
 496	}
 497	if (tp->t_rextents_delta) {
 498		be64_add_cpu(&sbp->sb_rextents, tp->t_rextents_delta);
 499		whole = 1;
 500	}
 501	if (tp->t_rextslog_delta) {
 502		sbp->sb_rextslog += tp->t_rextslog_delta;
 503		whole = 1;
 504	}
 505
 506	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
 507	if (whole)
 508		/*
 509		 * Log the whole thing, the fields are noncontiguous.
 510		 */
 511		xfs_trans_log_buf(tp, bp, 0, sizeof(xfs_dsb_t) - 1);
 512	else
 513		/*
 514		 * Since all the modifiable fields are contiguous, we
 515		 * can get away with this.
 516		 */
 517		xfs_trans_log_buf(tp, bp, offsetof(xfs_dsb_t, sb_icount),
 518				  offsetof(xfs_dsb_t, sb_frextents) +
 519				  sizeof(sbp->sb_frextents) - 1);
 520}
 521
 522STATIC int
 523xfs_sb_mod8(
 524	uint8_t			*field,
 525	int8_t			delta)
 526{
 527	int8_t			counter = *field;
 528
 529	counter += delta;
 530	if (counter < 0) {
 531		ASSERT(0);
 532		return -EINVAL;
 533	}
 534	*field = counter;
 535	return 0;
 536}
 537
 538STATIC int
 539xfs_sb_mod32(
 540	uint32_t		*field,
 541	int32_t			delta)
 542{
 543	int32_t			counter = *field;
 544
 545	counter += delta;
 546	if (counter < 0) {
 547		ASSERT(0);
 548		return -EINVAL;
 549	}
 550	*field = counter;
 551	return 0;
 552}
 553
 554STATIC int
 555xfs_sb_mod64(
 556	uint64_t		*field,
 557	int64_t			delta)
 558{
 559	int64_t			counter = *field;
 560
 561	counter += delta;
 562	if (counter < 0) {
 563		ASSERT(0);
 564		return -EINVAL;
 565	}
 566	*field = counter;
 567	return 0;
 568}
 569
 570/*
 571 * xfs_trans_unreserve_and_mod_sb() is called to release unused reservations
 572 * and apply superblock counter changes to the in-core superblock.  The
 573 * t_res_fdblocks_delta and t_res_frextents_delta fields are explicitly NOT
 574 * applied to the in-core superblock.  The idea is that that has already been
 575 * done.
 576 *
 577 * If we are not logging superblock counters, then the inode allocated/free and
 578 * used block counts are not updated in the on disk superblock. In this case,
 579 * XFS_TRANS_SB_DIRTY will not be set when the transaction is updated but we
 580 * still need to update the incore superblock with the changes.
 581 */
 582void
 583xfs_trans_unreserve_and_mod_sb(
 584	struct xfs_trans	*tp)
 585{
 586	struct xfs_mount	*mp = tp->t_mountp;
 587	bool			rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
 588	int64_t			blkdelta = 0;
 589	int64_t			rtxdelta = 0;
 590	int64_t			idelta = 0;
 591	int64_t			ifreedelta = 0;
 592	int			error;
 593
 594	/* calculate deltas */
 595	if (tp->t_blk_res > 0)
 596		blkdelta = tp->t_blk_res;
 597	if ((tp->t_fdblocks_delta != 0) &&
 598	    (xfs_sb_version_haslazysbcount(&mp->m_sb) ||
 599	     (tp->t_flags & XFS_TRANS_SB_DIRTY)))
 600	        blkdelta += tp->t_fdblocks_delta;
 601
 602	if (tp->t_rtx_res > 0)
 603		rtxdelta = tp->t_rtx_res;
 604	if ((tp->t_frextents_delta != 0) &&
 605	    (tp->t_flags & XFS_TRANS_SB_DIRTY))
 606		rtxdelta += tp->t_frextents_delta;
 607
 608	if (xfs_sb_version_haslazysbcount(&mp->m_sb) ||
 609	     (tp->t_flags & XFS_TRANS_SB_DIRTY)) {
 610		idelta = tp->t_icount_delta;
 611		ifreedelta = tp->t_ifree_delta;
 612	}
 613
 614	/* apply the per-cpu counters */
 615	if (blkdelta) {
 616		error = xfs_mod_fdblocks(mp, blkdelta, rsvd);
 617		if (error)
 618			goto out;
 619	}
 620
 621	if (idelta) {
 622		error = xfs_mod_icount(mp, idelta);
 623		if (error)
 624			goto out_undo_fdblocks;
 625	}
 626
 627	if (ifreedelta) {
 628		error = xfs_mod_ifree(mp, ifreedelta);
 629		if (error)
 630			goto out_undo_icount;
 631	}
 632
 633	if (rtxdelta == 0 && !(tp->t_flags & XFS_TRANS_SB_DIRTY))
 634		return;
 635
 636	/* apply remaining deltas */
 637	spin_lock(&mp->m_sb_lock);
 638	if (rtxdelta) {
 639		error = xfs_sb_mod64(&mp->m_sb.sb_frextents, rtxdelta);
 640		if (error)
 641			goto out_undo_ifree;
 642	}
 643
 644	if (tp->t_dblocks_delta != 0) {
 645		error = xfs_sb_mod64(&mp->m_sb.sb_dblocks, tp->t_dblocks_delta);
 646		if (error)
 647			goto out_undo_frextents;
 648	}
 649	if (tp->t_agcount_delta != 0) {
 650		error = xfs_sb_mod32(&mp->m_sb.sb_agcount, tp->t_agcount_delta);
 651		if (error)
 652			goto out_undo_dblocks;
 653	}
 654	if (tp->t_imaxpct_delta != 0) {
 655		error = xfs_sb_mod8(&mp->m_sb.sb_imax_pct, tp->t_imaxpct_delta);
 656		if (error)
 657			goto out_undo_agcount;
 658	}
 659	if (tp->t_rextsize_delta != 0) {
 660		error = xfs_sb_mod32(&mp->m_sb.sb_rextsize,
 661				     tp->t_rextsize_delta);
 662		if (error)
 663			goto out_undo_imaxpct;
 664	}
 665	if (tp->t_rbmblocks_delta != 0) {
 666		error = xfs_sb_mod32(&mp->m_sb.sb_rbmblocks,
 667				     tp->t_rbmblocks_delta);
 668		if (error)
 669			goto out_undo_rextsize;
 670	}
 671	if (tp->t_rblocks_delta != 0) {
 672		error = xfs_sb_mod64(&mp->m_sb.sb_rblocks, tp->t_rblocks_delta);
 673		if (error)
 674			goto out_undo_rbmblocks;
 675	}
 676	if (tp->t_rextents_delta != 0) {
 677		error = xfs_sb_mod64(&mp->m_sb.sb_rextents,
 678				     tp->t_rextents_delta);
 679		if (error)
 680			goto out_undo_rblocks;
 681	}
 682	if (tp->t_rextslog_delta != 0) {
 683		error = xfs_sb_mod8(&mp->m_sb.sb_rextslog,
 684				     tp->t_rextslog_delta);
 685		if (error)
 686			goto out_undo_rextents;
 687	}
 688	spin_unlock(&mp->m_sb_lock);
 689	return;
 690
 691out_undo_rextents:
 692	if (tp->t_rextents_delta)
 693		xfs_sb_mod64(&mp->m_sb.sb_rextents, -tp->t_rextents_delta);
 694out_undo_rblocks:
 695	if (tp->t_rblocks_delta)
 696		xfs_sb_mod64(&mp->m_sb.sb_rblocks, -tp->t_rblocks_delta);
 697out_undo_rbmblocks:
 698	if (tp->t_rbmblocks_delta)
 699		xfs_sb_mod32(&mp->m_sb.sb_rbmblocks, -tp->t_rbmblocks_delta);
 700out_undo_rextsize:
 701	if (tp->t_rextsize_delta)
 702		xfs_sb_mod32(&mp->m_sb.sb_rextsize, -tp->t_rextsize_delta);
 703out_undo_imaxpct:
 704	if (tp->t_rextsize_delta)
 705		xfs_sb_mod8(&mp->m_sb.sb_imax_pct, -tp->t_imaxpct_delta);
 706out_undo_agcount:
 707	if (tp->t_agcount_delta)
 708		xfs_sb_mod32(&mp->m_sb.sb_agcount, -tp->t_agcount_delta);
 709out_undo_dblocks:
 710	if (tp->t_dblocks_delta)
 711		xfs_sb_mod64(&mp->m_sb.sb_dblocks, -tp->t_dblocks_delta);
 712out_undo_frextents:
 713	if (rtxdelta)
 714		xfs_sb_mod64(&mp->m_sb.sb_frextents, -rtxdelta);
 715out_undo_ifree:
 716	spin_unlock(&mp->m_sb_lock);
 717	if (ifreedelta)
 718		xfs_mod_ifree(mp, -ifreedelta);
 719out_undo_icount:
 720	if (idelta)
 721		xfs_mod_icount(mp, -idelta);
 722out_undo_fdblocks:
 723	if (blkdelta)
 724		xfs_mod_fdblocks(mp, -blkdelta, rsvd);
 725out:
 726	ASSERT(error == 0);
 727	return;
 728}
 729
 730/*
 731 * Add the given log item to the transaction's list of log items.
 732 *
 733 * The log item will now point to its new descriptor with its li_desc field.
 734 */
 735void
 736xfs_trans_add_item(
 737	struct xfs_trans	*tp,
 738	struct xfs_log_item	*lip)
 739{
 740	struct xfs_log_item_desc *lidp;
 741
 742	ASSERT(lip->li_mountp == tp->t_mountp);
 743	ASSERT(lip->li_ailp == tp->t_mountp->m_ail);
 
 
 744
 745	lidp = kmem_zone_zalloc(xfs_log_item_desc_zone, KM_SLEEP | KM_NOFS);
 746
 747	lidp->lid_item = lip;
 748	lidp->lid_flags = 0;
 749	list_add_tail(&lidp->lid_trans, &tp->t_items);
 750
 751	lip->li_desc = lidp;
 752}
 753
 754STATIC void
 755xfs_trans_free_item_desc(
 756	struct xfs_log_item_desc *lidp)
 757{
 758	list_del_init(&lidp->lid_trans);
 759	kmem_zone_free(xfs_log_item_desc_zone, lidp);
 760}
 761
 762/*
 763 * Unlink and free the given descriptor.
 
 
 764 */
 765void
 766xfs_trans_del_item(
 767	struct xfs_log_item	*lip)
 768{
 769	xfs_trans_free_item_desc(lip->li_desc);
 770	lip->li_desc = NULL;
 771}
 772
 773/*
 774 * Unlock all of the items of a transaction and free all the descriptors
 775 * of that transaction.
 776 */
 777void
 778xfs_trans_free_items(
 779	struct xfs_trans	*tp,
 780	xfs_lsn_t		commit_lsn,
 781	bool			abort)
 782{
 783	struct xfs_log_item_desc *lidp, *next;
 784
 785	list_for_each_entry_safe(lidp, next, &tp->t_items, lid_trans) {
 786		struct xfs_log_item	*lip = lidp->lid_item;
 787
 788		lip->li_desc = NULL;
 789
 790		if (commit_lsn != NULLCOMMITLSN)
 791			lip->li_ops->iop_committing(lip, commit_lsn);
 792		if (abort)
 793			lip->li_flags |= XFS_LI_ABORTED;
 794		lip->li_ops->iop_unlock(lip);
 795
 796		xfs_trans_free_item_desc(lidp);
 797	}
 798}
 799
 800static inline void
 801xfs_log_item_batch_insert(
 802	struct xfs_ail		*ailp,
 803	struct xfs_ail_cursor	*cur,
 804	struct xfs_log_item	**log_items,
 805	int			nr_items,
 806	xfs_lsn_t		commit_lsn)
 807{
 808	int	i;
 809
 810	spin_lock(&ailp->ail_lock);
 811	/* xfs_trans_ail_update_bulk drops ailp->ail_lock */
 812	xfs_trans_ail_update_bulk(ailp, cur, log_items, nr_items, commit_lsn);
 813
 814	for (i = 0; i < nr_items; i++) {
 815		struct xfs_log_item *lip = log_items[i];
 816
 817		lip->li_ops->iop_unpin(lip, 0);
 
 818	}
 819}
 820
 821/*
 822 * Bulk operation version of xfs_trans_committed that takes a log vector of
 823 * items to insert into the AIL. This uses bulk AIL insertion techniques to
 824 * minimise lock traffic.
 825 *
 826 * If we are called with the aborted flag set, it is because a log write during
 827 * a CIL checkpoint commit has failed. In this case, all the items in the
 828 * checkpoint have already gone through iop_commited and iop_unlock, which
 829 * means that checkpoint commit abort handling is treated exactly the same
 830 * as an iclog write error even though we haven't started any IO yet. Hence in
 831 * this case all we need to do is iop_committed processing, followed by an
 832 * iop_unpin(aborted) call.
 833 *
 834 * The AIL cursor is used to optimise the insert process. If commit_lsn is not
 835 * at the end of the AIL, the insert cursor avoids the need to walk
 836 * the AIL to find the insertion point on every xfs_log_item_batch_insert()
 837 * call. This saves a lot of needless list walking and is a net win, even
 838 * though it slightly increases that amount of AIL lock traffic to set it up
 839 * and tear it down.
 840 */
 841void
 842xfs_trans_committed_bulk(
 843	struct xfs_ail		*ailp,
 844	struct xfs_log_vec	*log_vector,
 845	xfs_lsn_t		commit_lsn,
 846	int			aborted)
 847{
 848#define LOG_ITEM_BATCH_SIZE	32
 849	struct xfs_log_item	*log_items[LOG_ITEM_BATCH_SIZE];
 850	struct xfs_log_vec	*lv;
 851	struct xfs_ail_cursor	cur;
 852	int			i = 0;
 853
 854	spin_lock(&ailp->ail_lock);
 855	xfs_trans_ail_cursor_last(ailp, &cur, commit_lsn);
 856	spin_unlock(&ailp->ail_lock);
 857
 858	/* unpin all the log items */
 859	for (lv = log_vector; lv; lv = lv->lv_next ) {
 860		struct xfs_log_item	*lip = lv->lv_item;
 861		xfs_lsn_t		item_lsn;
 862
 863		if (aborted)
 864			lip->li_flags |= XFS_LI_ABORTED;
 865		item_lsn = lip->li_ops->iop_committed(lip, commit_lsn);
 
 
 
 
 
 
 
 
 
 866
 867		/* item_lsn of -1 means the item needs no further processing */
 868		if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0)
 869			continue;
 870
 871		/*
 872		 * if we are aborting the operation, no point in inserting the
 873		 * object into the AIL as we are in a shutdown situation.
 874		 */
 875		if (aborted) {
 876			ASSERT(XFS_FORCED_SHUTDOWN(ailp->ail_mount));
 877			lip->li_ops->iop_unpin(lip, 1);
 
 878			continue;
 879		}
 880
 881		if (item_lsn != commit_lsn) {
 882
 883			/*
 884			 * Not a bulk update option due to unusual item_lsn.
 885			 * Push into AIL immediately, rechecking the lsn once
 886			 * we have the ail lock. Then unpin the item. This does
 887			 * not affect the AIL cursor the bulk insert path is
 888			 * using.
 889			 */
 890			spin_lock(&ailp->ail_lock);
 891			if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0)
 892				xfs_trans_ail_update(ailp, lip, item_lsn);
 893			else
 894				spin_unlock(&ailp->ail_lock);
 895			lip->li_ops->iop_unpin(lip, 0);
 
 896			continue;
 897		}
 898
 899		/* Item is a candidate for bulk AIL insert.  */
 900		log_items[i++] = lv->lv_item;
 901		if (i >= LOG_ITEM_BATCH_SIZE) {
 902			xfs_log_item_batch_insert(ailp, &cur, log_items,
 903					LOG_ITEM_BATCH_SIZE, commit_lsn);
 904			i = 0;
 905		}
 906	}
 907
 908	/* make sure we insert the remainder! */
 909	if (i)
 910		xfs_log_item_batch_insert(ailp, &cur, log_items, i, commit_lsn);
 911
 912	spin_lock(&ailp->ail_lock);
 913	xfs_trans_ail_cursor_done(&cur);
 914	spin_unlock(&ailp->ail_lock);
 915}
 916
 917/*
 918 * Commit the given transaction to the log.
 919 *
 920 * XFS disk error handling mechanism is not based on a typical
 921 * transaction abort mechanism. Logically after the filesystem
 922 * gets marked 'SHUTDOWN', we can't let any new transactions
 923 * be durable - ie. committed to disk - because some metadata might
 924 * be inconsistent. In such cases, this returns an error, and the
 925 * caller may assume that all locked objects joined to the transaction
 926 * have already been unlocked as if the commit had succeeded.
 927 * Do not reference the transaction structure after this call.
 928 */
 929static int
 930__xfs_trans_commit(
 931	struct xfs_trans	*tp,
 932	bool			regrant)
 933{
 934	struct xfs_mount	*mp = tp->t_mountp;
 935	xfs_lsn_t		commit_lsn = -1;
 936	int			error = 0;
 937	int			sync = tp->t_flags & XFS_TRANS_SYNC;
 938
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 939	/*
 940	 * If there is nothing to be logged by the transaction,
 941	 * then unlock all of the items associated with the
 942	 * transaction and free the transaction structure.
 943	 * Also make sure to return any reserved blocks to
 944	 * the free pool.
 945	 */
 946	if (!(tp->t_flags & XFS_TRANS_DIRTY))
 947		goto out_unreserve;
 948
 949	if (XFS_FORCED_SHUTDOWN(mp)) {
 950		error = -EIO;
 951		goto out_unreserve;
 952	}
 953
 954	ASSERT(tp->t_ticket != NULL);
 955
 956	/*
 957	 * If we need to update the superblock, then do it now.
 958	 */
 959	if (tp->t_flags & XFS_TRANS_SB_DIRTY)
 960		xfs_trans_apply_sb_deltas(tp);
 961	xfs_trans_apply_dquot_deltas(tp);
 962
 963	xfs_log_commit_cil(mp, tp, &commit_lsn, regrant);
 964
 965	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 966	xfs_trans_free(tp);
 967
 968	/*
 969	 * If the transaction needs to be synchronous, then force the
 970	 * log out now and wait for it.
 971	 */
 972	if (sync) {
 973		error = xfs_log_force_lsn(mp, commit_lsn, XFS_LOG_SYNC, NULL);
 974		XFS_STATS_INC(mp, xs_trans_sync);
 975	} else {
 976		XFS_STATS_INC(mp, xs_trans_async);
 977	}
 978
 979	return error;
 980
 981out_unreserve:
 982	xfs_trans_unreserve_and_mod_sb(tp);
 983
 984	/*
 985	 * It is indeed possible for the transaction to be not dirty but
 986	 * the dqinfo portion to be.  All that means is that we have some
 987	 * (non-persistent) quota reservations that need to be unreserved.
 988	 */
 989	xfs_trans_unreserve_and_mod_dquots(tp);
 990	if (tp->t_ticket) {
 991		commit_lsn = xfs_log_done(mp, tp->t_ticket, NULL, regrant);
 992		if (commit_lsn == -1 && !error)
 993			error = -EIO;
 
 994	}
 995	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 996	xfs_trans_free_items(tp, NULLCOMMITLSN, !!error);
 997	xfs_trans_free(tp);
 998
 999	XFS_STATS_INC(mp, xs_trans_empty);
1000	return error;
1001}
1002
1003int
1004xfs_trans_commit(
1005	struct xfs_trans	*tp)
1006{
1007	return __xfs_trans_commit(tp, false);
1008}
1009
1010/*
1011 * Unlock all of the transaction's items and free the transaction.
1012 * The transaction must not have modified any of its items, because
1013 * there is no way to restore them to their previous state.
1014 *
1015 * If the transaction has made a log reservation, make sure to release
1016 * it as well.
1017 */
1018void
1019xfs_trans_cancel(
1020	struct xfs_trans	*tp)
1021{
1022	struct xfs_mount	*mp = tp->t_mountp;
1023	bool			dirty = (tp->t_flags & XFS_TRANS_DIRTY);
1024
 
 
 
 
 
1025	/*
1026	 * See if the caller is relying on us to shut down the
1027	 * filesystem.  This happens in paths where we detect
1028	 * corruption and decide to give up.
1029	 */
1030	if (dirty && !XFS_FORCED_SHUTDOWN(mp)) {
1031		XFS_ERROR_REPORT("xfs_trans_cancel", XFS_ERRLEVEL_LOW, mp);
1032		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1033	}
1034#ifdef DEBUG
1035	if (!dirty && !XFS_FORCED_SHUTDOWN(mp)) {
1036		struct xfs_log_item_desc *lidp;
1037
1038		list_for_each_entry(lidp, &tp->t_items, lid_trans)
1039			ASSERT(!(lidp->lid_item->li_type == XFS_LI_EFD));
1040	}
1041#endif
1042	xfs_trans_unreserve_and_mod_sb(tp);
1043	xfs_trans_unreserve_and_mod_dquots(tp);
1044
1045	if (tp->t_ticket)
1046		xfs_log_done(mp, tp->t_ticket, NULL, false);
 
 
1047
1048	/* mark this thread as no longer being in a transaction */
1049	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
1050
1051	xfs_trans_free_items(tp, NULLCOMMITLSN, dirty);
1052	xfs_trans_free(tp);
1053}
1054
1055/*
1056 * Roll from one trans in the sequence of PERMANENT transactions to
1057 * the next: permanent transactions are only flushed out when
1058 * committed with xfs_trans_commit(), but we still want as soon
1059 * as possible to let chunks of it go to the log. So we commit the
1060 * chunk we've been working on and get a new transaction to continue.
1061 */
1062int
1063xfs_trans_roll(
1064	struct xfs_trans	**tpp)
1065{
1066	struct xfs_trans	*trans = *tpp;
1067	struct xfs_trans_res	tres;
1068	int			error;
 
 
1069
1070	/*
1071	 * Copy the critical parameters from one trans to the next.
1072	 */
1073	tres.tr_logres = trans->t_log_res;
1074	tres.tr_logcount = trans->t_log_count;
1075
1076	*tpp = xfs_trans_dup(trans);
1077
1078	/*
1079	 * Commit the current transaction.
1080	 * If this commit failed, then it'd just unlock those items that
1081	 * are not marked ihold. That also means that a filesystem shutdown
1082	 * is in progress. The caller takes the responsibility to cancel
1083	 * the duplicate transaction that gets returned.
1084	 */
1085	error = __xfs_trans_commit(trans, true);
1086	if (error)
1087		return error;
1088
1089	/*
1090	 * Reserve space in the log for the next transaction.
1091	 * This also pushes items in the "AIL", the list of logged items,
1092	 * out to disk if they are taking up space at the tail of the log
1093	 * that we want to use.  This requires that either nothing be locked
1094	 * across this call, or that anything that is locked be logged in
1095	 * the prior and the next transactions.
1096	 */
1097	tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
1098	return xfs_trans_reserve(*tpp, &tres, 0, 0);
1099}
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   4 * Copyright (C) 2010 Red Hat, Inc.
   5 * All Rights Reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
   6 */
   7#include "xfs.h"
   8#include "xfs_fs.h"
   9#include "xfs_shared.h"
  10#include "xfs_format.h"
  11#include "xfs_log_format.h"
  12#include "xfs_trans_resv.h"
  13#include "xfs_mount.h"
 
  14#include "xfs_extent_busy.h"
  15#include "xfs_quota.h"
  16#include "xfs_trans.h"
  17#include "xfs_trans_priv.h"
  18#include "xfs_log.h"
  19#include "xfs_trace.h"
  20#include "xfs_error.h"
  21#include "xfs_defer.h"
  22
  23kmem_zone_t	*xfs_trans_zone;
 
  24
  25#if defined(CONFIG_TRACEPOINTS)
  26static void
  27xfs_trans_trace_reservations(
  28	struct xfs_mount	*mp)
  29{
  30	struct xfs_trans_res	resv;
  31	struct xfs_trans_res	*res;
  32	struct xfs_trans_res	*end_res;
  33	int			i;
  34
  35	res = (struct xfs_trans_res *)M_RES(mp);
  36	end_res = (struct xfs_trans_res *)(M_RES(mp) + 1);
  37	for (i = 0; res < end_res; i++, res++)
  38		trace_xfs_trans_resv_calc(mp, i, res);
  39	xfs_log_get_max_trans_res(mp, &resv);
  40	trace_xfs_trans_resv_calc(mp, -1, &resv);
  41}
  42#else
  43# define xfs_trans_trace_reservations(mp)
  44#endif
  45
  46/*
  47 * Initialize the precomputed transaction reservation values
  48 * in the mount structure.
  49 */
  50void
  51xfs_trans_init(
  52	struct xfs_mount	*mp)
  53{
  54	xfs_trans_resv_calc(mp, M_RES(mp));
  55	xfs_trans_trace_reservations(mp);
  56}
  57
  58/*
  59 * Free the transaction structure.  If there is more clean up
  60 * to do when the structure is freed, add it here.
  61 */
  62STATIC void
  63xfs_trans_free(
  64	struct xfs_trans	*tp)
  65{
  66	xfs_extent_busy_sort(&tp->t_busy);
  67	xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false);
  68
  69	trace_xfs_trans_free(tp, _RET_IP_);
  70	atomic_dec(&tp->t_mountp->m_active_trans);
  71	if (!(tp->t_flags & XFS_TRANS_NO_WRITECOUNT))
  72		sb_end_intwrite(tp->t_mountp->m_super);
  73	xfs_trans_free_dqinfo(tp);
  74	kmem_zone_free(xfs_trans_zone, tp);
  75}
  76
  77/*
  78 * This is called to create a new transaction which will share the
  79 * permanent log reservation of the given transaction.  The remaining
  80 * unused block and rt extent reservations are also inherited.  This
  81 * implies that the original transaction is no longer allowed to allocate
  82 * blocks.  Locks and log items, however, are no inherited.  They must
  83 * be added to the new transaction explicitly.
  84 */
  85STATIC struct xfs_trans *
  86xfs_trans_dup(
  87	struct xfs_trans	*tp)
  88{
  89	struct xfs_trans	*ntp;
  90
  91	trace_xfs_trans_dup(tp, _RET_IP_);
  92
  93	ntp = kmem_zone_zalloc(xfs_trans_zone, 0);
  94
  95	/*
  96	 * Initialize the new transaction structure.
  97	 */
  98	ntp->t_magic = XFS_TRANS_HEADER_MAGIC;
  99	ntp->t_mountp = tp->t_mountp;
 100	INIT_LIST_HEAD(&ntp->t_items);
 101	INIT_LIST_HEAD(&ntp->t_busy);
 102	INIT_LIST_HEAD(&ntp->t_dfops);
 103	ntp->t_firstblock = NULLFSBLOCK;
 104
 105	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
 106	ASSERT(tp->t_ticket != NULL);
 107
 108	ntp->t_flags = XFS_TRANS_PERM_LOG_RES |
 109		       (tp->t_flags & XFS_TRANS_RESERVE) |
 110		       (tp->t_flags & XFS_TRANS_NO_WRITECOUNT);
 111	/* We gave our writer reference to the new transaction */
 112	tp->t_flags |= XFS_TRANS_NO_WRITECOUNT;
 113	ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
 114
 115	ASSERT(tp->t_blk_res >= tp->t_blk_res_used);
 116	ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
 117	tp->t_blk_res = tp->t_blk_res_used;
 118
 119	ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used;
 120	tp->t_rtx_res = tp->t_rtx_res_used;
 121	ntp->t_pflags = tp->t_pflags;
 122
 123	/* move deferred ops over to the new tp */
 124	xfs_defer_move(ntp, tp);
 125
 126	xfs_trans_dup_dqinfo(tp, ntp);
 127
 128	atomic_inc(&tp->t_mountp->m_active_trans);
 129	return ntp;
 130}
 131
 132/*
 133 * This is called to reserve free disk blocks and log space for the
 134 * given transaction.  This must be done before allocating any resources
 135 * within the transaction.
 136 *
 137 * This will return ENOSPC if there are not enough blocks available.
 138 * It will sleep waiting for available log space.
 139 * The only valid value for the flags parameter is XFS_RES_LOG_PERM, which
 140 * is used by long running transactions.  If any one of the reservations
 141 * fails then they will all be backed out.
 142 *
 143 * This does not do quota reservations. That typically is done by the
 144 * caller afterwards.
 145 */
 146static int
 147xfs_trans_reserve(
 148	struct xfs_trans	*tp,
 149	struct xfs_trans_res	*resp,
 150	uint			blocks,
 151	uint			rtextents)
 152{
 153	int		error = 0;
 154	bool		rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
 155
 156	/* Mark this thread as being in a transaction */
 157	current_set_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 158
 159	/*
 160	 * Attempt to reserve the needed disk blocks by decrementing
 161	 * the number needed from the number available.  This will
 162	 * fail if the count would go below zero.
 163	 */
 164	if (blocks > 0) {
 165		error = xfs_mod_fdblocks(tp->t_mountp, -((int64_t)blocks), rsvd);
 166		if (error != 0) {
 167			current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 168			return -ENOSPC;
 169		}
 170		tp->t_blk_res += blocks;
 171	}
 172
 173	/*
 174	 * Reserve the log space needed for this transaction.
 175	 */
 176	if (resp->tr_logres > 0) {
 177		bool	permanent = false;
 178
 179		ASSERT(tp->t_log_res == 0 ||
 180		       tp->t_log_res == resp->tr_logres);
 181		ASSERT(tp->t_log_count == 0 ||
 182		       tp->t_log_count == resp->tr_logcount);
 183
 184		if (resp->tr_logflags & XFS_TRANS_PERM_LOG_RES) {
 185			tp->t_flags |= XFS_TRANS_PERM_LOG_RES;
 186			permanent = true;
 187		} else {
 188			ASSERT(tp->t_ticket == NULL);
 189			ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
 190		}
 191
 192		if (tp->t_ticket != NULL) {
 193			ASSERT(resp->tr_logflags & XFS_TRANS_PERM_LOG_RES);
 194			error = xfs_log_regrant(tp->t_mountp, tp->t_ticket);
 195		} else {
 196			error = xfs_log_reserve(tp->t_mountp,
 197						resp->tr_logres,
 198						resp->tr_logcount,
 199						&tp->t_ticket, XFS_TRANSACTION,
 200						permanent);
 201		}
 202
 203		if (error)
 204			goto undo_blocks;
 205
 206		tp->t_log_res = resp->tr_logres;
 207		tp->t_log_count = resp->tr_logcount;
 208	}
 209
 210	/*
 211	 * Attempt to reserve the needed realtime extents by decrementing
 212	 * the number needed from the number available.  This will
 213	 * fail if the count would go below zero.
 214	 */
 215	if (rtextents > 0) {
 216		error = xfs_mod_frextents(tp->t_mountp, -((int64_t)rtextents));
 217		if (error) {
 218			error = -ENOSPC;
 219			goto undo_log;
 220		}
 221		tp->t_rtx_res += rtextents;
 222	}
 223
 224	return 0;
 225
 226	/*
 227	 * Error cases jump to one of these labels to undo any
 228	 * reservations which have already been performed.
 229	 */
 230undo_log:
 231	if (resp->tr_logres > 0) {
 232		xfs_log_done(tp->t_mountp, tp->t_ticket, NULL, false);
 233		tp->t_ticket = NULL;
 234		tp->t_log_res = 0;
 235		tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES;
 236	}
 237
 238undo_blocks:
 239	if (blocks > 0) {
 240		xfs_mod_fdblocks(tp->t_mountp, (int64_t)blocks, rsvd);
 241		tp->t_blk_res = 0;
 242	}
 243
 244	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 245
 246	return error;
 247}
 248
 249int
 250xfs_trans_alloc(
 251	struct xfs_mount	*mp,
 252	struct xfs_trans_res	*resp,
 253	uint			blocks,
 254	uint			rtextents,
 255	uint			flags,
 256	struct xfs_trans	**tpp)
 257{
 258	struct xfs_trans	*tp;
 259	int			error;
 260
 261	/*
 262	 * Allocate the handle before we do our freeze accounting and setting up
 263	 * GFP_NOFS allocation context so that we avoid lockdep false positives
 264	 * by doing GFP_KERNEL allocations inside sb_start_intwrite().
 265	 */
 266	tp = kmem_zone_zalloc(xfs_trans_zone, 0);
 267	if (!(flags & XFS_TRANS_NO_WRITECOUNT))
 268		sb_start_intwrite(mp->m_super);
 269
 270	/*
 271	 * Zero-reservation ("empty") transactions can't modify anything, so
 272	 * they're allowed to run while we're frozen.
 273	 */
 274	WARN_ON(resp->tr_logres > 0 &&
 275		mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE);
 276	atomic_inc(&mp->m_active_trans);
 277
 
 
 278	tp->t_magic = XFS_TRANS_HEADER_MAGIC;
 279	tp->t_flags = flags;
 280	tp->t_mountp = mp;
 281	INIT_LIST_HEAD(&tp->t_items);
 282	INIT_LIST_HEAD(&tp->t_busy);
 283	INIT_LIST_HEAD(&tp->t_dfops);
 284	tp->t_firstblock = NULLFSBLOCK;
 285
 286	error = xfs_trans_reserve(tp, resp, blocks, rtextents);
 287	if (error) {
 288		xfs_trans_cancel(tp);
 289		return error;
 290	}
 291
 292	trace_xfs_trans_alloc(tp, _RET_IP_);
 293
 294	*tpp = tp;
 295	return 0;
 296}
 297
 298/*
 299 * Create an empty transaction with no reservation.  This is a defensive
 300 * mechanism for routines that query metadata without actually modifying
 301 * them -- if the metadata being queried is somehow cross-linked (think a
 302 * btree block pointer that points higher in the tree), we risk deadlock.
 303 * However, blocks grabbed as part of a transaction can be re-grabbed.
 304 * The verifiers will notice the corrupt block and the operation will fail
 305 * back to userspace without deadlocking.
 306 *
 307 * Note the zero-length reservation; this transaction MUST be cancelled
 308 * without any dirty data.
 309 */
 310int
 311xfs_trans_alloc_empty(
 312	struct xfs_mount		*mp,
 313	struct xfs_trans		**tpp)
 314{
 315	struct xfs_trans_res		resv = {0};
 316
 317	return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp);
 318}
 319
 320/*
 321 * Record the indicated change to the given field for application
 322 * to the file system's superblock when the transaction commits.
 323 * For now, just store the change in the transaction structure.
 324 *
 325 * Mark the transaction structure to indicate that the superblock
 326 * needs to be updated before committing.
 327 *
 328 * Because we may not be keeping track of allocated/free inodes and
 329 * used filesystem blocks in the superblock, we do not mark the
 330 * superblock dirty in this transaction if we modify these fields.
 331 * We still need to update the transaction deltas so that they get
 332 * applied to the incore superblock, but we don't want them to
 333 * cause the superblock to get locked and logged if these are the
 334 * only fields in the superblock that the transaction modifies.
 335 */
 336void
 337xfs_trans_mod_sb(
 338	xfs_trans_t	*tp,
 339	uint		field,
 340	int64_t		delta)
 341{
 342	uint32_t	flags = (XFS_TRANS_DIRTY|XFS_TRANS_SB_DIRTY);
 343	xfs_mount_t	*mp = tp->t_mountp;
 344
 345	switch (field) {
 346	case XFS_TRANS_SB_ICOUNT:
 347		tp->t_icount_delta += delta;
 348		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 349			flags &= ~XFS_TRANS_SB_DIRTY;
 350		break;
 351	case XFS_TRANS_SB_IFREE:
 352		tp->t_ifree_delta += delta;
 353		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 354			flags &= ~XFS_TRANS_SB_DIRTY;
 355		break;
 356	case XFS_TRANS_SB_FDBLOCKS:
 357		/*
 358		 * Track the number of blocks allocated in the transaction.
 359		 * Make sure it does not exceed the number reserved. If so,
 360		 * shutdown as this can lead to accounting inconsistency.
 361		 */
 362		if (delta < 0) {
 363			tp->t_blk_res_used += (uint)-delta;
 364			if (tp->t_blk_res_used > tp->t_blk_res)
 365				xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 366		}
 367		tp->t_fdblocks_delta += delta;
 368		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 369			flags &= ~XFS_TRANS_SB_DIRTY;
 370		break;
 371	case XFS_TRANS_SB_RES_FDBLOCKS:
 372		/*
 373		 * The allocation has already been applied to the
 374		 * in-core superblock's counter.  This should only
 375		 * be applied to the on-disk superblock.
 376		 */
 377		tp->t_res_fdblocks_delta += delta;
 378		if (xfs_sb_version_haslazysbcount(&mp->m_sb))
 379			flags &= ~XFS_TRANS_SB_DIRTY;
 380		break;
 381	case XFS_TRANS_SB_FREXTENTS:
 382		/*
 383		 * Track the number of blocks allocated in the
 384		 * transaction.  Make sure it does not exceed the
 385		 * number reserved.
 386		 */
 387		if (delta < 0) {
 388			tp->t_rtx_res_used += (uint)-delta;
 389			ASSERT(tp->t_rtx_res_used <= tp->t_rtx_res);
 390		}
 391		tp->t_frextents_delta += delta;
 392		break;
 393	case XFS_TRANS_SB_RES_FREXTENTS:
 394		/*
 395		 * The allocation has already been applied to the
 396		 * in-core superblock's counter.  This should only
 397		 * be applied to the on-disk superblock.
 398		 */
 399		ASSERT(delta < 0);
 400		tp->t_res_frextents_delta += delta;
 401		break;
 402	case XFS_TRANS_SB_DBLOCKS:
 403		ASSERT(delta > 0);
 404		tp->t_dblocks_delta += delta;
 405		break;
 406	case XFS_TRANS_SB_AGCOUNT:
 407		ASSERT(delta > 0);
 408		tp->t_agcount_delta += delta;
 409		break;
 410	case XFS_TRANS_SB_IMAXPCT:
 411		tp->t_imaxpct_delta += delta;
 412		break;
 413	case XFS_TRANS_SB_REXTSIZE:
 414		tp->t_rextsize_delta += delta;
 415		break;
 416	case XFS_TRANS_SB_RBMBLOCKS:
 417		tp->t_rbmblocks_delta += delta;
 418		break;
 419	case XFS_TRANS_SB_RBLOCKS:
 420		tp->t_rblocks_delta += delta;
 421		break;
 422	case XFS_TRANS_SB_REXTENTS:
 423		tp->t_rextents_delta += delta;
 424		break;
 425	case XFS_TRANS_SB_REXTSLOG:
 426		tp->t_rextslog_delta += delta;
 427		break;
 428	default:
 429		ASSERT(0);
 430		return;
 431	}
 432
 433	tp->t_flags |= flags;
 434}
 435
 436/*
 437 * xfs_trans_apply_sb_deltas() is called from the commit code
 438 * to bring the superblock buffer into the current transaction
 439 * and modify it as requested by earlier calls to xfs_trans_mod_sb().
 440 *
 441 * For now we just look at each field allowed to change and change
 442 * it if necessary.
 443 */
 444STATIC void
 445xfs_trans_apply_sb_deltas(
 446	xfs_trans_t	*tp)
 447{
 448	xfs_dsb_t	*sbp;
 449	xfs_buf_t	*bp;
 450	int		whole = 0;
 451
 452	bp = xfs_trans_getsb(tp, tp->t_mountp);
 453	sbp = XFS_BUF_TO_SBP(bp);
 454
 455	/*
 456	 * Check that superblock mods match the mods made to AGF counters.
 457	 */
 458	ASSERT((tp->t_fdblocks_delta + tp->t_res_fdblocks_delta) ==
 459	       (tp->t_ag_freeblks_delta + tp->t_ag_flist_delta +
 460		tp->t_ag_btree_delta));
 461
 462	/*
 463	 * Only update the superblock counters if we are logging them
 464	 */
 465	if (!xfs_sb_version_haslazysbcount(&(tp->t_mountp->m_sb))) {
 466		if (tp->t_icount_delta)
 467			be64_add_cpu(&sbp->sb_icount, tp->t_icount_delta);
 468		if (tp->t_ifree_delta)
 469			be64_add_cpu(&sbp->sb_ifree, tp->t_ifree_delta);
 470		if (tp->t_fdblocks_delta)
 471			be64_add_cpu(&sbp->sb_fdblocks, tp->t_fdblocks_delta);
 472		if (tp->t_res_fdblocks_delta)
 473			be64_add_cpu(&sbp->sb_fdblocks, tp->t_res_fdblocks_delta);
 474	}
 475
 476	if (tp->t_frextents_delta)
 477		be64_add_cpu(&sbp->sb_frextents, tp->t_frextents_delta);
 478	if (tp->t_res_frextents_delta)
 479		be64_add_cpu(&sbp->sb_frextents, tp->t_res_frextents_delta);
 480
 481	if (tp->t_dblocks_delta) {
 482		be64_add_cpu(&sbp->sb_dblocks, tp->t_dblocks_delta);
 483		whole = 1;
 484	}
 485	if (tp->t_agcount_delta) {
 486		be32_add_cpu(&sbp->sb_agcount, tp->t_agcount_delta);
 487		whole = 1;
 488	}
 489	if (tp->t_imaxpct_delta) {
 490		sbp->sb_imax_pct += tp->t_imaxpct_delta;
 491		whole = 1;
 492	}
 493	if (tp->t_rextsize_delta) {
 494		be32_add_cpu(&sbp->sb_rextsize, tp->t_rextsize_delta);
 495		whole = 1;
 496	}
 497	if (tp->t_rbmblocks_delta) {
 498		be32_add_cpu(&sbp->sb_rbmblocks, tp->t_rbmblocks_delta);
 499		whole = 1;
 500	}
 501	if (tp->t_rblocks_delta) {
 502		be64_add_cpu(&sbp->sb_rblocks, tp->t_rblocks_delta);
 503		whole = 1;
 504	}
 505	if (tp->t_rextents_delta) {
 506		be64_add_cpu(&sbp->sb_rextents, tp->t_rextents_delta);
 507		whole = 1;
 508	}
 509	if (tp->t_rextslog_delta) {
 510		sbp->sb_rextslog += tp->t_rextslog_delta;
 511		whole = 1;
 512	}
 513
 514	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
 515	if (whole)
 516		/*
 517		 * Log the whole thing, the fields are noncontiguous.
 518		 */
 519		xfs_trans_log_buf(tp, bp, 0, sizeof(xfs_dsb_t) - 1);
 520	else
 521		/*
 522		 * Since all the modifiable fields are contiguous, we
 523		 * can get away with this.
 524		 */
 525		xfs_trans_log_buf(tp, bp, offsetof(xfs_dsb_t, sb_icount),
 526				  offsetof(xfs_dsb_t, sb_frextents) +
 527				  sizeof(sbp->sb_frextents) - 1);
 528}
 529
 530STATIC int
 531xfs_sb_mod8(
 532	uint8_t			*field,
 533	int8_t			delta)
 534{
 535	int8_t			counter = *field;
 536
 537	counter += delta;
 538	if (counter < 0) {
 539		ASSERT(0);
 540		return -EINVAL;
 541	}
 542	*field = counter;
 543	return 0;
 544}
 545
 546STATIC int
 547xfs_sb_mod32(
 548	uint32_t		*field,
 549	int32_t			delta)
 550{
 551	int32_t			counter = *field;
 552
 553	counter += delta;
 554	if (counter < 0) {
 555		ASSERT(0);
 556		return -EINVAL;
 557	}
 558	*field = counter;
 559	return 0;
 560}
 561
 562STATIC int
 563xfs_sb_mod64(
 564	uint64_t		*field,
 565	int64_t			delta)
 566{
 567	int64_t			counter = *field;
 568
 569	counter += delta;
 570	if (counter < 0) {
 571		ASSERT(0);
 572		return -EINVAL;
 573	}
 574	*field = counter;
 575	return 0;
 576}
 577
 578/*
 579 * xfs_trans_unreserve_and_mod_sb() is called to release unused reservations
 580 * and apply superblock counter changes to the in-core superblock.  The
 581 * t_res_fdblocks_delta and t_res_frextents_delta fields are explicitly NOT
 582 * applied to the in-core superblock.  The idea is that that has already been
 583 * done.
 584 *
 585 * If we are not logging superblock counters, then the inode allocated/free and
 586 * used block counts are not updated in the on disk superblock. In this case,
 587 * XFS_TRANS_SB_DIRTY will not be set when the transaction is updated but we
 588 * still need to update the incore superblock with the changes.
 589 */
 590void
 591xfs_trans_unreserve_and_mod_sb(
 592	struct xfs_trans	*tp)
 593{
 594	struct xfs_mount	*mp = tp->t_mountp;
 595	bool			rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
 596	int64_t			blkdelta = 0;
 597	int64_t			rtxdelta = 0;
 598	int64_t			idelta = 0;
 599	int64_t			ifreedelta = 0;
 600	int			error;
 601
 602	/* calculate deltas */
 603	if (tp->t_blk_res > 0)
 604		blkdelta = tp->t_blk_res;
 605	if ((tp->t_fdblocks_delta != 0) &&
 606	    (xfs_sb_version_haslazysbcount(&mp->m_sb) ||
 607	     (tp->t_flags & XFS_TRANS_SB_DIRTY)))
 608	        blkdelta += tp->t_fdblocks_delta;
 609
 610	if (tp->t_rtx_res > 0)
 611		rtxdelta = tp->t_rtx_res;
 612	if ((tp->t_frextents_delta != 0) &&
 613	    (tp->t_flags & XFS_TRANS_SB_DIRTY))
 614		rtxdelta += tp->t_frextents_delta;
 615
 616	if (xfs_sb_version_haslazysbcount(&mp->m_sb) ||
 617	     (tp->t_flags & XFS_TRANS_SB_DIRTY)) {
 618		idelta = tp->t_icount_delta;
 619		ifreedelta = tp->t_ifree_delta;
 620	}
 621
 622	/* apply the per-cpu counters */
 623	if (blkdelta) {
 624		error = xfs_mod_fdblocks(mp, blkdelta, rsvd);
 625		if (error)
 626			goto out;
 627	}
 628
 629	if (idelta) {
 630		error = xfs_mod_icount(mp, idelta);
 631		if (error)
 632			goto out_undo_fdblocks;
 633	}
 634
 635	if (ifreedelta) {
 636		error = xfs_mod_ifree(mp, ifreedelta);
 637		if (error)
 638			goto out_undo_icount;
 639	}
 640
 641	if (rtxdelta == 0 && !(tp->t_flags & XFS_TRANS_SB_DIRTY))
 642		return;
 643
 644	/* apply remaining deltas */
 645	spin_lock(&mp->m_sb_lock);
 646	if (rtxdelta) {
 647		error = xfs_sb_mod64(&mp->m_sb.sb_frextents, rtxdelta);
 648		if (error)
 649			goto out_undo_ifree;
 650	}
 651
 652	if (tp->t_dblocks_delta != 0) {
 653		error = xfs_sb_mod64(&mp->m_sb.sb_dblocks, tp->t_dblocks_delta);
 654		if (error)
 655			goto out_undo_frextents;
 656	}
 657	if (tp->t_agcount_delta != 0) {
 658		error = xfs_sb_mod32(&mp->m_sb.sb_agcount, tp->t_agcount_delta);
 659		if (error)
 660			goto out_undo_dblocks;
 661	}
 662	if (tp->t_imaxpct_delta != 0) {
 663		error = xfs_sb_mod8(&mp->m_sb.sb_imax_pct, tp->t_imaxpct_delta);
 664		if (error)
 665			goto out_undo_agcount;
 666	}
 667	if (tp->t_rextsize_delta != 0) {
 668		error = xfs_sb_mod32(&mp->m_sb.sb_rextsize,
 669				     tp->t_rextsize_delta);
 670		if (error)
 671			goto out_undo_imaxpct;
 672	}
 673	if (tp->t_rbmblocks_delta != 0) {
 674		error = xfs_sb_mod32(&mp->m_sb.sb_rbmblocks,
 675				     tp->t_rbmblocks_delta);
 676		if (error)
 677			goto out_undo_rextsize;
 678	}
 679	if (tp->t_rblocks_delta != 0) {
 680		error = xfs_sb_mod64(&mp->m_sb.sb_rblocks, tp->t_rblocks_delta);
 681		if (error)
 682			goto out_undo_rbmblocks;
 683	}
 684	if (tp->t_rextents_delta != 0) {
 685		error = xfs_sb_mod64(&mp->m_sb.sb_rextents,
 686				     tp->t_rextents_delta);
 687		if (error)
 688			goto out_undo_rblocks;
 689	}
 690	if (tp->t_rextslog_delta != 0) {
 691		error = xfs_sb_mod8(&mp->m_sb.sb_rextslog,
 692				     tp->t_rextslog_delta);
 693		if (error)
 694			goto out_undo_rextents;
 695	}
 696	spin_unlock(&mp->m_sb_lock);
 697	return;
 698
 699out_undo_rextents:
 700	if (tp->t_rextents_delta)
 701		xfs_sb_mod64(&mp->m_sb.sb_rextents, -tp->t_rextents_delta);
 702out_undo_rblocks:
 703	if (tp->t_rblocks_delta)
 704		xfs_sb_mod64(&mp->m_sb.sb_rblocks, -tp->t_rblocks_delta);
 705out_undo_rbmblocks:
 706	if (tp->t_rbmblocks_delta)
 707		xfs_sb_mod32(&mp->m_sb.sb_rbmblocks, -tp->t_rbmblocks_delta);
 708out_undo_rextsize:
 709	if (tp->t_rextsize_delta)
 710		xfs_sb_mod32(&mp->m_sb.sb_rextsize, -tp->t_rextsize_delta);
 711out_undo_imaxpct:
 712	if (tp->t_rextsize_delta)
 713		xfs_sb_mod8(&mp->m_sb.sb_imax_pct, -tp->t_imaxpct_delta);
 714out_undo_agcount:
 715	if (tp->t_agcount_delta)
 716		xfs_sb_mod32(&mp->m_sb.sb_agcount, -tp->t_agcount_delta);
 717out_undo_dblocks:
 718	if (tp->t_dblocks_delta)
 719		xfs_sb_mod64(&mp->m_sb.sb_dblocks, -tp->t_dblocks_delta);
 720out_undo_frextents:
 721	if (rtxdelta)
 722		xfs_sb_mod64(&mp->m_sb.sb_frextents, -rtxdelta);
 723out_undo_ifree:
 724	spin_unlock(&mp->m_sb_lock);
 725	if (ifreedelta)
 726		xfs_mod_ifree(mp, -ifreedelta);
 727out_undo_icount:
 728	if (idelta)
 729		xfs_mod_icount(mp, -idelta);
 730out_undo_fdblocks:
 731	if (blkdelta)
 732		xfs_mod_fdblocks(mp, -blkdelta, rsvd);
 733out:
 734	ASSERT(error == 0);
 735	return;
 736}
 737
 738/* Add the given log item to the transaction's list of log items. */
 
 
 
 
 739void
 740xfs_trans_add_item(
 741	struct xfs_trans	*tp,
 742	struct xfs_log_item	*lip)
 743{
 
 
 744	ASSERT(lip->li_mountp == tp->t_mountp);
 745	ASSERT(lip->li_ailp == tp->t_mountp->m_ail);
 746	ASSERT(list_empty(&lip->li_trans));
 747	ASSERT(!test_bit(XFS_LI_DIRTY, &lip->li_flags));
 748
 749	list_add_tail(&lip->li_trans, &tp->t_items);
 750	trace_xfs_trans_add_item(tp, _RET_IP_);
 
 
 
 
 
 
 
 
 
 
 
 
 
 751}
 752
 753/*
 754 * Unlink the log item from the transaction. the log item is no longer
 755 * considered dirty in this transaction, as the linked transaction has
 756 * finished, either by abort or commit completion.
 757 */
 758void
 759xfs_trans_del_item(
 760	struct xfs_log_item	*lip)
 761{
 762	clear_bit(XFS_LI_DIRTY, &lip->li_flags);
 763	list_del_init(&lip->li_trans);
 764}
 765
 766/* Detach and unlock all of the items in a transaction */
 767static void
 
 
 
 768xfs_trans_free_items(
 769	struct xfs_trans	*tp,
 
 770	bool			abort)
 771{
 772	struct xfs_log_item	*lip, *next;
 773
 774	trace_xfs_trans_free_items(tp, _RET_IP_);
 
 775
 776	list_for_each_entry_safe(lip, next, &tp->t_items, li_trans) {
 777		xfs_trans_del_item(lip);
 
 
 778		if (abort)
 779			set_bit(XFS_LI_ABORTED, &lip->li_flags);
 780		if (lip->li_ops->iop_release)
 781			lip->li_ops->iop_release(lip);
 
 782	}
 783}
 784
 785static inline void
 786xfs_log_item_batch_insert(
 787	struct xfs_ail		*ailp,
 788	struct xfs_ail_cursor	*cur,
 789	struct xfs_log_item	**log_items,
 790	int			nr_items,
 791	xfs_lsn_t		commit_lsn)
 792{
 793	int	i;
 794
 795	spin_lock(&ailp->ail_lock);
 796	/* xfs_trans_ail_update_bulk drops ailp->ail_lock */
 797	xfs_trans_ail_update_bulk(ailp, cur, log_items, nr_items, commit_lsn);
 798
 799	for (i = 0; i < nr_items; i++) {
 800		struct xfs_log_item *lip = log_items[i];
 801
 802		if (lip->li_ops->iop_unpin)
 803			lip->li_ops->iop_unpin(lip, 0);
 804	}
 805}
 806
 807/*
 808 * Bulk operation version of xfs_trans_committed that takes a log vector of
 809 * items to insert into the AIL. This uses bulk AIL insertion techniques to
 810 * minimise lock traffic.
 811 *
 812 * If we are called with the aborted flag set, it is because a log write during
 813 * a CIL checkpoint commit has failed. In this case, all the items in the
 814 * checkpoint have already gone through iop_committed and iop_committing, which
 815 * means that checkpoint commit abort handling is treated exactly the same
 816 * as an iclog write error even though we haven't started any IO yet. Hence in
 817 * this case all we need to do is iop_committed processing, followed by an
 818 * iop_unpin(aborted) call.
 819 *
 820 * The AIL cursor is used to optimise the insert process. If commit_lsn is not
 821 * at the end of the AIL, the insert cursor avoids the need to walk
 822 * the AIL to find the insertion point on every xfs_log_item_batch_insert()
 823 * call. This saves a lot of needless list walking and is a net win, even
 824 * though it slightly increases that amount of AIL lock traffic to set it up
 825 * and tear it down.
 826 */
 827void
 828xfs_trans_committed_bulk(
 829	struct xfs_ail		*ailp,
 830	struct xfs_log_vec	*log_vector,
 831	xfs_lsn_t		commit_lsn,
 832	bool			aborted)
 833{
 834#define LOG_ITEM_BATCH_SIZE	32
 835	struct xfs_log_item	*log_items[LOG_ITEM_BATCH_SIZE];
 836	struct xfs_log_vec	*lv;
 837	struct xfs_ail_cursor	cur;
 838	int			i = 0;
 839
 840	spin_lock(&ailp->ail_lock);
 841	xfs_trans_ail_cursor_last(ailp, &cur, commit_lsn);
 842	spin_unlock(&ailp->ail_lock);
 843
 844	/* unpin all the log items */
 845	for (lv = log_vector; lv; lv = lv->lv_next ) {
 846		struct xfs_log_item	*lip = lv->lv_item;
 847		xfs_lsn_t		item_lsn;
 848
 849		if (aborted)
 850			set_bit(XFS_LI_ABORTED, &lip->li_flags);
 851
 852		if (lip->li_ops->flags & XFS_ITEM_RELEASE_WHEN_COMMITTED) {
 853			lip->li_ops->iop_release(lip);
 854			continue;
 855		}
 856
 857		if (lip->li_ops->iop_committed)
 858			item_lsn = lip->li_ops->iop_committed(lip, commit_lsn);
 859		else
 860			item_lsn = commit_lsn;
 861
 862		/* item_lsn of -1 means the item needs no further processing */
 863		if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0)
 864			continue;
 865
 866		/*
 867		 * if we are aborting the operation, no point in inserting the
 868		 * object into the AIL as we are in a shutdown situation.
 869		 */
 870		if (aborted) {
 871			ASSERT(XFS_FORCED_SHUTDOWN(ailp->ail_mount));
 872			if (lip->li_ops->iop_unpin)
 873				lip->li_ops->iop_unpin(lip, 1);
 874			continue;
 875		}
 876
 877		if (item_lsn != commit_lsn) {
 878
 879			/*
 880			 * Not a bulk update option due to unusual item_lsn.
 881			 * Push into AIL immediately, rechecking the lsn once
 882			 * we have the ail lock. Then unpin the item. This does
 883			 * not affect the AIL cursor the bulk insert path is
 884			 * using.
 885			 */
 886			spin_lock(&ailp->ail_lock);
 887			if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0)
 888				xfs_trans_ail_update(ailp, lip, item_lsn);
 889			else
 890				spin_unlock(&ailp->ail_lock);
 891			if (lip->li_ops->iop_unpin)
 892				lip->li_ops->iop_unpin(lip, 0);
 893			continue;
 894		}
 895
 896		/* Item is a candidate for bulk AIL insert.  */
 897		log_items[i++] = lv->lv_item;
 898		if (i >= LOG_ITEM_BATCH_SIZE) {
 899			xfs_log_item_batch_insert(ailp, &cur, log_items,
 900					LOG_ITEM_BATCH_SIZE, commit_lsn);
 901			i = 0;
 902		}
 903	}
 904
 905	/* make sure we insert the remainder! */
 906	if (i)
 907		xfs_log_item_batch_insert(ailp, &cur, log_items, i, commit_lsn);
 908
 909	spin_lock(&ailp->ail_lock);
 910	xfs_trans_ail_cursor_done(&cur);
 911	spin_unlock(&ailp->ail_lock);
 912}
 913
 914/*
 915 * Commit the given transaction to the log.
 916 *
 917 * XFS disk error handling mechanism is not based on a typical
 918 * transaction abort mechanism. Logically after the filesystem
 919 * gets marked 'SHUTDOWN', we can't let any new transactions
 920 * be durable - ie. committed to disk - because some metadata might
 921 * be inconsistent. In such cases, this returns an error, and the
 922 * caller may assume that all locked objects joined to the transaction
 923 * have already been unlocked as if the commit had succeeded.
 924 * Do not reference the transaction structure after this call.
 925 */
 926static int
 927__xfs_trans_commit(
 928	struct xfs_trans	*tp,
 929	bool			regrant)
 930{
 931	struct xfs_mount	*mp = tp->t_mountp;
 932	xfs_lsn_t		commit_lsn = -1;
 933	int			error = 0;
 934	int			sync = tp->t_flags & XFS_TRANS_SYNC;
 935
 936	trace_xfs_trans_commit(tp, _RET_IP_);
 937
 938	/*
 939	 * Finish deferred items on final commit. Only permanent transactions
 940	 * should ever have deferred ops.
 941	 */
 942	WARN_ON_ONCE(!list_empty(&tp->t_dfops) &&
 943		     !(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
 944	if (!regrant && (tp->t_flags & XFS_TRANS_PERM_LOG_RES)) {
 945		error = xfs_defer_finish_noroll(&tp);
 946		if (error)
 947			goto out_unreserve;
 948	}
 949
 950	/*
 951	 * If there is nothing to be logged by the transaction,
 952	 * then unlock all of the items associated with the
 953	 * transaction and free the transaction structure.
 954	 * Also make sure to return any reserved blocks to
 955	 * the free pool.
 956	 */
 957	if (!(tp->t_flags & XFS_TRANS_DIRTY))
 958		goto out_unreserve;
 959
 960	if (XFS_FORCED_SHUTDOWN(mp)) {
 961		error = -EIO;
 962		goto out_unreserve;
 963	}
 964
 965	ASSERT(tp->t_ticket != NULL);
 966
 967	/*
 968	 * If we need to update the superblock, then do it now.
 969	 */
 970	if (tp->t_flags & XFS_TRANS_SB_DIRTY)
 971		xfs_trans_apply_sb_deltas(tp);
 972	xfs_trans_apply_dquot_deltas(tp);
 973
 974	xfs_log_commit_cil(mp, tp, &commit_lsn, regrant);
 975
 976	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
 977	xfs_trans_free(tp);
 978
 979	/*
 980	 * If the transaction needs to be synchronous, then force the
 981	 * log out now and wait for it.
 982	 */
 983	if (sync) {
 984		error = xfs_log_force_lsn(mp, commit_lsn, XFS_LOG_SYNC, NULL);
 985		XFS_STATS_INC(mp, xs_trans_sync);
 986	} else {
 987		XFS_STATS_INC(mp, xs_trans_async);
 988	}
 989
 990	return error;
 991
 992out_unreserve:
 993	xfs_trans_unreserve_and_mod_sb(tp);
 994
 995	/*
 996	 * It is indeed possible for the transaction to be not dirty but
 997	 * the dqinfo portion to be.  All that means is that we have some
 998	 * (non-persistent) quota reservations that need to be unreserved.
 999	 */
1000	xfs_trans_unreserve_and_mod_dquots(tp);
1001	if (tp->t_ticket) {
1002		commit_lsn = xfs_log_done(mp, tp->t_ticket, NULL, regrant);
1003		if (commit_lsn == -1 && !error)
1004			error = -EIO;
1005		tp->t_ticket = NULL;
1006	}
1007	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
1008	xfs_trans_free_items(tp, !!error);
1009	xfs_trans_free(tp);
1010
1011	XFS_STATS_INC(mp, xs_trans_empty);
1012	return error;
1013}
1014
1015int
1016xfs_trans_commit(
1017	struct xfs_trans	*tp)
1018{
1019	return __xfs_trans_commit(tp, false);
1020}
1021
1022/*
1023 * Unlock all of the transaction's items and free the transaction.
1024 * The transaction must not have modified any of its items, because
1025 * there is no way to restore them to their previous state.
1026 *
1027 * If the transaction has made a log reservation, make sure to release
1028 * it as well.
1029 */
1030void
1031xfs_trans_cancel(
1032	struct xfs_trans	*tp)
1033{
1034	struct xfs_mount	*mp = tp->t_mountp;
1035	bool			dirty = (tp->t_flags & XFS_TRANS_DIRTY);
1036
1037	trace_xfs_trans_cancel(tp, _RET_IP_);
1038
1039	if (tp->t_flags & XFS_TRANS_PERM_LOG_RES)
1040		xfs_defer_cancel(tp);
1041
1042	/*
1043	 * See if the caller is relying on us to shut down the
1044	 * filesystem.  This happens in paths where we detect
1045	 * corruption and decide to give up.
1046	 */
1047	if (dirty && !XFS_FORCED_SHUTDOWN(mp)) {
1048		XFS_ERROR_REPORT("xfs_trans_cancel", XFS_ERRLEVEL_LOW, mp);
1049		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1050	}
1051#ifdef DEBUG
1052	if (!dirty && !XFS_FORCED_SHUTDOWN(mp)) {
1053		struct xfs_log_item *lip;
1054
1055		list_for_each_entry(lip, &tp->t_items, li_trans)
1056			ASSERT(!(lip->li_type == XFS_LI_EFD));
1057	}
1058#endif
1059	xfs_trans_unreserve_and_mod_sb(tp);
1060	xfs_trans_unreserve_and_mod_dquots(tp);
1061
1062	if (tp->t_ticket) {
1063		xfs_log_done(mp, tp->t_ticket, NULL, false);
1064		tp->t_ticket = NULL;
1065	}
1066
1067	/* mark this thread as no longer being in a transaction */
1068	current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS);
1069
1070	xfs_trans_free_items(tp, dirty);
1071	xfs_trans_free(tp);
1072}
1073
1074/*
1075 * Roll from one trans in the sequence of PERMANENT transactions to
1076 * the next: permanent transactions are only flushed out when
1077 * committed with xfs_trans_commit(), but we still want as soon
1078 * as possible to let chunks of it go to the log. So we commit the
1079 * chunk we've been working on and get a new transaction to continue.
1080 */
1081int
1082xfs_trans_roll(
1083	struct xfs_trans	**tpp)
1084{
1085	struct xfs_trans	*trans = *tpp;
1086	struct xfs_trans_res	tres;
1087	int			error;
1088
1089	trace_xfs_trans_roll(trans, _RET_IP_);
1090
1091	/*
1092	 * Copy the critical parameters from one trans to the next.
1093	 */
1094	tres.tr_logres = trans->t_log_res;
1095	tres.tr_logcount = trans->t_log_count;
1096
1097	*tpp = xfs_trans_dup(trans);
1098
1099	/*
1100	 * Commit the current transaction.
1101	 * If this commit failed, then it'd just unlock those items that
1102	 * are not marked ihold. That also means that a filesystem shutdown
1103	 * is in progress. The caller takes the responsibility to cancel
1104	 * the duplicate transaction that gets returned.
1105	 */
1106	error = __xfs_trans_commit(trans, true);
1107	if (error)
1108		return error;
1109
1110	/*
1111	 * Reserve space in the log for the next transaction.
1112	 * This also pushes items in the "AIL", the list of logged items,
1113	 * out to disk if they are taking up space at the tail of the log
1114	 * that we want to use.  This requires that either nothing be locked
1115	 * across this call, or that anything that is locked be logged in
1116	 * the prior and the next transactions.
1117	 */
1118	tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
1119	return xfs_trans_reserve(*tpp, &tres, 0, 0);
1120}