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v5.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/* -*- mode: c; c-basic-offset: 8; -*-
   3 * vim: noexpandtab sw=8 ts=8 sts=0:
   4 *
   5 * localalloc.c
   6 *
   7 * Node local data allocation
   8 *
   9 * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  10 */
  11
  12#include <linux/fs.h>
  13#include <linux/types.h>
  14#include <linux/slab.h>
  15#include <linux/highmem.h>
  16#include <linux/bitops.h>
  17
  18#include <cluster/masklog.h>
  19
  20#include "ocfs2.h"
  21
  22#include "alloc.h"
  23#include "blockcheck.h"
  24#include "dlmglue.h"
  25#include "inode.h"
  26#include "journal.h"
  27#include "localalloc.h"
  28#include "suballoc.h"
  29#include "super.h"
  30#include "sysfile.h"
  31#include "ocfs2_trace.h"
  32
  33#include "buffer_head_io.h"
  34
  35#define OCFS2_LOCAL_ALLOC(dinode)	(&((dinode)->id2.i_lab))
  36
  37static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc);
  38
  39static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb,
  40					     struct ocfs2_dinode *alloc,
  41					     u32 *numbits,
  42					     struct ocfs2_alloc_reservation *resv);
  43
  44static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc);
  45
  46static int ocfs2_sync_local_to_main(struct ocfs2_super *osb,
  47				    handle_t *handle,
  48				    struct ocfs2_dinode *alloc,
  49				    struct inode *main_bm_inode,
  50				    struct buffer_head *main_bm_bh);
  51
  52static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb,
  53						struct ocfs2_alloc_context **ac,
  54						struct inode **bitmap_inode,
  55						struct buffer_head **bitmap_bh);
  56
  57static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb,
  58					handle_t *handle,
  59					struct ocfs2_alloc_context *ac);
  60
  61static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb,
  62					  struct inode *local_alloc_inode);
  63
  64/*
  65 * ocfs2_la_default_mb() - determine a default size, in megabytes of
  66 * the local alloc.
  67 *
  68 * Generally, we'd like to pick as large a local alloc as
  69 * possible. Performance on large workloads tends to scale
  70 * proportionally to la size. In addition to that, the reservations
  71 * code functions more efficiently as it can reserve more windows for
  72 * write.
  73 *
  74 * Some things work against us when trying to choose a large local alloc:
  75 *
  76 * - We need to ensure our sizing is picked to leave enough space in
  77 *   group descriptors for other allocations (such as block groups,
  78 *   etc). Picking default sizes which are a multiple of 4 could help
  79 *   - block groups are allocated in 2mb and 4mb chunks.
  80 *
  81 * - Likewise, we don't want to starve other nodes of bits on small
  82 *   file systems. This can easily be taken care of by limiting our
  83 *   default to a reasonable size (256M) on larger cluster sizes.
  84 *
  85 * - Some file systems can't support very large sizes - 4k and 8k in
  86 *   particular are limited to less than 128 and 256 megabytes respectively.
  87 *
  88 * The following reference table shows group descriptor and local
  89 * alloc maximums at various cluster sizes (4k blocksize)
  90 *
  91 * csize: 4K	group: 126M	la: 121M
  92 * csize: 8K	group: 252M	la: 243M
  93 * csize: 16K	group: 504M	la: 486M
  94 * csize: 32K	group: 1008M	la: 972M
  95 * csize: 64K	group: 2016M	la: 1944M
  96 * csize: 128K	group: 4032M	la: 3888M
  97 * csize: 256K	group: 8064M	la: 7776M
  98 * csize: 512K	group: 16128M	la: 15552M
  99 * csize: 1024K	group: 32256M	la: 31104M
 100 */
 101#define	OCFS2_LA_MAX_DEFAULT_MB	256
 102#define	OCFS2_LA_OLD_DEFAULT	8
 103unsigned int ocfs2_la_default_mb(struct ocfs2_super *osb)
 104{
 105	unsigned int la_mb;
 106	unsigned int gd_mb;
 107	unsigned int la_max_mb;
 108	unsigned int megs_per_slot;
 109	struct super_block *sb = osb->sb;
 110
 111	gd_mb = ocfs2_clusters_to_megabytes(osb->sb,
 112		8 * ocfs2_group_bitmap_size(sb, 0, osb->s_feature_incompat));
 113
 114	/*
 115	 * This takes care of files systems with very small group
 116	 * descriptors - 512 byte blocksize at cluster sizes lower
 117	 * than 16K and also 1k blocksize with 4k cluster size.
 118	 */
 119	if ((sb->s_blocksize == 512 && osb->s_clustersize <= 8192)
 120	    || (sb->s_blocksize == 1024 && osb->s_clustersize == 4096))
 121		return OCFS2_LA_OLD_DEFAULT;
 122
 123	/*
 124	 * Leave enough room for some block groups and make the final
 125	 * value we work from a multiple of 4.
 126	 */
 127	gd_mb -= 16;
 128	gd_mb &= 0xFFFFFFFB;
 129
 130	la_mb = gd_mb;
 131
 132	/*
 133	 * Keep window sizes down to a reasonable default
 134	 */
 135	if (la_mb > OCFS2_LA_MAX_DEFAULT_MB) {
 136		/*
 137		 * Some clustersize / blocksize combinations will have
 138		 * given us a larger than OCFS2_LA_MAX_DEFAULT_MB
 139		 * default size, but get poor distribution when
 140		 * limited to exactly 256 megabytes.
 141		 *
 142		 * As an example, 16K clustersize at 4K blocksize
 143		 * gives us a cluster group size of 504M. Paring the
 144		 * local alloc size down to 256 however, would give us
 145		 * only one window and around 200MB left in the
 146		 * cluster group. Instead, find the first size below
 147		 * 256 which would give us an even distribution.
 148		 *
 149		 * Larger cluster group sizes actually work out pretty
 150		 * well when pared to 256, so we don't have to do this
 151		 * for any group that fits more than two
 152		 * OCFS2_LA_MAX_DEFAULT_MB windows.
 153		 */
 154		if (gd_mb > (2 * OCFS2_LA_MAX_DEFAULT_MB))
 155			la_mb = 256;
 156		else {
 157			unsigned int gd_mult = gd_mb;
 158
 159			while (gd_mult > 256)
 160				gd_mult = gd_mult >> 1;
 161
 162			la_mb = gd_mult;
 163		}
 164	}
 165
 166	megs_per_slot = osb->osb_clusters_at_boot / osb->max_slots;
 167	megs_per_slot = ocfs2_clusters_to_megabytes(osb->sb, megs_per_slot);
 168	/* Too many nodes, too few disk clusters. */
 169	if (megs_per_slot < la_mb)
 170		la_mb = megs_per_slot;
 171
 172	/* We can't store more bits than we can in a block. */
 173	la_max_mb = ocfs2_clusters_to_megabytes(osb->sb,
 174						ocfs2_local_alloc_size(sb) * 8);
 175	if (la_mb > la_max_mb)
 176		la_mb = la_max_mb;
 177
 178	return la_mb;
 179}
 180
 181void ocfs2_la_set_sizes(struct ocfs2_super *osb, int requested_mb)
 182{
 183	struct super_block *sb = osb->sb;
 184	unsigned int la_default_mb = ocfs2_la_default_mb(osb);
 185	unsigned int la_max_mb;
 186
 187	la_max_mb = ocfs2_clusters_to_megabytes(sb,
 188						ocfs2_local_alloc_size(sb) * 8);
 189
 190	trace_ocfs2_la_set_sizes(requested_mb, la_max_mb, la_default_mb);
 191
 192	if (requested_mb == -1) {
 193		/* No user request - use defaults */
 194		osb->local_alloc_default_bits =
 195			ocfs2_megabytes_to_clusters(sb, la_default_mb);
 196	} else if (requested_mb > la_max_mb) {
 197		/* Request is too big, we give the maximum available */
 198		osb->local_alloc_default_bits =
 199			ocfs2_megabytes_to_clusters(sb, la_max_mb);
 200	} else {
 201		osb->local_alloc_default_bits =
 202			ocfs2_megabytes_to_clusters(sb, requested_mb);
 203	}
 204
 205	osb->local_alloc_bits = osb->local_alloc_default_bits;
 206}
 207
 208static inline int ocfs2_la_state_enabled(struct ocfs2_super *osb)
 209{
 210	return (osb->local_alloc_state == OCFS2_LA_THROTTLED ||
 211		osb->local_alloc_state == OCFS2_LA_ENABLED);
 212}
 213
 214void ocfs2_local_alloc_seen_free_bits(struct ocfs2_super *osb,
 215				      unsigned int num_clusters)
 216{
 217	spin_lock(&osb->osb_lock);
 218	if (osb->local_alloc_state == OCFS2_LA_DISABLED ||
 219	    osb->local_alloc_state == OCFS2_LA_THROTTLED)
 220		if (num_clusters >= osb->local_alloc_default_bits) {
 221			cancel_delayed_work(&osb->la_enable_wq);
 222			osb->local_alloc_state = OCFS2_LA_ENABLED;
 223		}
 224	spin_unlock(&osb->osb_lock);
 225}
 226
 227void ocfs2_la_enable_worker(struct work_struct *work)
 228{
 229	struct ocfs2_super *osb =
 230		container_of(work, struct ocfs2_super,
 231			     la_enable_wq.work);
 232	spin_lock(&osb->osb_lock);
 233	osb->local_alloc_state = OCFS2_LA_ENABLED;
 234	spin_unlock(&osb->osb_lock);
 235}
 236
 237/*
 238 * Tell us whether a given allocation should use the local alloc
 239 * file. Otherwise, it has to go to the main bitmap.
 240 *
 241 * This function does semi-dirty reads of local alloc size and state!
 242 * This is ok however, as the values are re-checked once under mutex.
 243 */
 244int ocfs2_alloc_should_use_local(struct ocfs2_super *osb, u64 bits)
 245{
 246	int ret = 0;
 247	int la_bits;
 248
 249	spin_lock(&osb->osb_lock);
 250	la_bits = osb->local_alloc_bits;
 251
 252	if (!ocfs2_la_state_enabled(osb))
 253		goto bail;
 254
 255	/* la_bits should be at least twice the size (in clusters) of
 256	 * a new block group. We want to be sure block group
 257	 * allocations go through the local alloc, so allow an
 258	 * allocation to take up to half the bitmap. */
 259	if (bits > (la_bits / 2))
 260		goto bail;
 261
 262	ret = 1;
 263bail:
 264	trace_ocfs2_alloc_should_use_local(
 265	     (unsigned long long)bits, osb->local_alloc_state, la_bits, ret);
 266	spin_unlock(&osb->osb_lock);
 267	return ret;
 268}
 269
 270int ocfs2_load_local_alloc(struct ocfs2_super *osb)
 271{
 272	int status = 0;
 273	struct ocfs2_dinode *alloc = NULL;
 274	struct buffer_head *alloc_bh = NULL;
 275	u32 num_used;
 276	struct inode *inode = NULL;
 277	struct ocfs2_local_alloc *la;
 278
 279	if (osb->local_alloc_bits == 0)
 280		goto bail;
 281
 282	if (osb->local_alloc_bits >= osb->bitmap_cpg) {
 283		mlog(ML_NOTICE, "Requested local alloc window %d is larger "
 284		     "than max possible %u. Using defaults.\n",
 285		     osb->local_alloc_bits, (osb->bitmap_cpg - 1));
 286		osb->local_alloc_bits =
 287			ocfs2_megabytes_to_clusters(osb->sb,
 288						    ocfs2_la_default_mb(osb));
 289	}
 290
 291	/* read the alloc off disk */
 292	inode = ocfs2_get_system_file_inode(osb, LOCAL_ALLOC_SYSTEM_INODE,
 293					    osb->slot_num);
 294	if (!inode) {
 295		status = -EINVAL;
 296		mlog_errno(status);
 297		goto bail;
 298	}
 299
 300	status = ocfs2_read_inode_block_full(inode, &alloc_bh,
 301					     OCFS2_BH_IGNORE_CACHE);
 302	if (status < 0) {
 303		mlog_errno(status);
 304		goto bail;
 305	}
 306
 307	alloc = (struct ocfs2_dinode *) alloc_bh->b_data;
 308	la = OCFS2_LOCAL_ALLOC(alloc);
 309
 310	if (!(le32_to_cpu(alloc->i_flags) &
 311	    (OCFS2_LOCAL_ALLOC_FL|OCFS2_BITMAP_FL))) {
 312		mlog(ML_ERROR, "Invalid local alloc inode, %llu\n",
 313		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
 314		status = -EINVAL;
 315		goto bail;
 316	}
 317
 318	if ((la->la_size == 0) ||
 319	    (le16_to_cpu(la->la_size) > ocfs2_local_alloc_size(inode->i_sb))) {
 320		mlog(ML_ERROR, "Local alloc size is invalid (la_size = %u)\n",
 321		     le16_to_cpu(la->la_size));
 322		status = -EINVAL;
 323		goto bail;
 324	}
 325
 326	/* do a little verification. */
 327	num_used = ocfs2_local_alloc_count_bits(alloc);
 328
 329	/* hopefully the local alloc has always been recovered before
 330	 * we load it. */
 331	if (num_used
 332	    || alloc->id1.bitmap1.i_used
 333	    || alloc->id1.bitmap1.i_total
 334	    || la->la_bm_off) {
 335		mlog(ML_ERROR, "inconsistent detected, clean journal with"
 336		     " unrecovered local alloc, please run fsck.ocfs2!\n"
 337		     "found = %u, set = %u, taken = %u, off = %u\n",
 338		     num_used, le32_to_cpu(alloc->id1.bitmap1.i_used),
 339		     le32_to_cpu(alloc->id1.bitmap1.i_total),
 340		     OCFS2_LOCAL_ALLOC(alloc)->la_bm_off);
 341
 342		status = -EINVAL;
 343		goto bail;
 344	}
 345
 346	osb->local_alloc_bh = alloc_bh;
 347	osb->local_alloc_state = OCFS2_LA_ENABLED;
 348
 349bail:
 350	if (status < 0)
 351		brelse(alloc_bh);
 352	iput(inode);
 
 353
 354	trace_ocfs2_load_local_alloc(osb->local_alloc_bits);
 355
 356	if (status)
 357		mlog_errno(status);
 358	return status;
 359}
 360
 361/*
 362 * return any unused bits to the bitmap and write out a clean
 363 * local_alloc.
 364 *
 365 * local_alloc_bh is optional. If not passed, we will simply use the
 366 * one off osb. If you do pass it however, be warned that it *will* be
 367 * returned brelse'd and NULL'd out.*/
 368void ocfs2_shutdown_local_alloc(struct ocfs2_super *osb)
 369{
 370	int status;
 371	handle_t *handle;
 372	struct inode *local_alloc_inode = NULL;
 373	struct buffer_head *bh = NULL;
 374	struct buffer_head *main_bm_bh = NULL;
 375	struct inode *main_bm_inode = NULL;
 376	struct ocfs2_dinode *alloc_copy = NULL;
 377	struct ocfs2_dinode *alloc = NULL;
 378
 379	cancel_delayed_work(&osb->la_enable_wq);
 380	if (osb->ocfs2_wq)
 381		flush_workqueue(osb->ocfs2_wq);
 382
 383	if (osb->local_alloc_state == OCFS2_LA_UNUSED)
 384		goto out;
 385
 386	local_alloc_inode =
 387		ocfs2_get_system_file_inode(osb,
 388					    LOCAL_ALLOC_SYSTEM_INODE,
 389					    osb->slot_num);
 390	if (!local_alloc_inode) {
 391		status = -ENOENT;
 392		mlog_errno(status);
 393		goto out;
 394	}
 395
 396	osb->local_alloc_state = OCFS2_LA_DISABLED;
 397
 398	ocfs2_resmap_uninit(&osb->osb_la_resmap);
 399
 400	main_bm_inode = ocfs2_get_system_file_inode(osb,
 401						    GLOBAL_BITMAP_SYSTEM_INODE,
 402						    OCFS2_INVALID_SLOT);
 403	if (!main_bm_inode) {
 404		status = -EINVAL;
 405		mlog_errno(status);
 406		goto out;
 407	}
 408
 409	inode_lock(main_bm_inode);
 410
 411	status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
 412	if (status < 0) {
 413		mlog_errno(status);
 414		goto out_mutex;
 415	}
 416
 417	/* WINDOW_MOVE_CREDITS is a bit heavy... */
 418	handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS);
 419	if (IS_ERR(handle)) {
 420		mlog_errno(PTR_ERR(handle));
 421		handle = NULL;
 422		goto out_unlock;
 423	}
 424
 425	bh = osb->local_alloc_bh;
 426	alloc = (struct ocfs2_dinode *) bh->b_data;
 427
 428	alloc_copy = kmemdup(alloc, bh->b_size, GFP_NOFS);
 429	if (!alloc_copy) {
 430		status = -ENOMEM;
 431		goto out_commit;
 432	}
 
 433
 434	status = ocfs2_journal_access_di(handle, INODE_CACHE(local_alloc_inode),
 435					 bh, OCFS2_JOURNAL_ACCESS_WRITE);
 436	if (status < 0) {
 437		mlog_errno(status);
 438		goto out_commit;
 439	}
 440
 441	ocfs2_clear_local_alloc(alloc);
 442	ocfs2_journal_dirty(handle, bh);
 443
 444	brelse(bh);
 445	osb->local_alloc_bh = NULL;
 446	osb->local_alloc_state = OCFS2_LA_UNUSED;
 447
 448	status = ocfs2_sync_local_to_main(osb, handle, alloc_copy,
 449					  main_bm_inode, main_bm_bh);
 450	if (status < 0)
 451		mlog_errno(status);
 452
 453out_commit:
 454	ocfs2_commit_trans(osb, handle);
 455
 456out_unlock:
 457	brelse(main_bm_bh);
 458
 459	ocfs2_inode_unlock(main_bm_inode, 1);
 460
 461out_mutex:
 462	inode_unlock(main_bm_inode);
 463	iput(main_bm_inode);
 464
 465out:
 466	iput(local_alloc_inode);
 
 467
 468	kfree(alloc_copy);
 469}
 470
 471/*
 472 * We want to free the bitmap bits outside of any recovery context as
 473 * we'll need a cluster lock to do so, but we must clear the local
 474 * alloc before giving up the recovered nodes journal. To solve this,
 475 * we kmalloc a copy of the local alloc before it's change for the
 476 * caller to process with ocfs2_complete_local_alloc_recovery
 477 */
 478int ocfs2_begin_local_alloc_recovery(struct ocfs2_super *osb,
 479				     int slot_num,
 480				     struct ocfs2_dinode **alloc_copy)
 481{
 482	int status = 0;
 483	struct buffer_head *alloc_bh = NULL;
 484	struct inode *inode = NULL;
 485	struct ocfs2_dinode *alloc;
 486
 487	trace_ocfs2_begin_local_alloc_recovery(slot_num);
 488
 489	*alloc_copy = NULL;
 490
 491	inode = ocfs2_get_system_file_inode(osb,
 492					    LOCAL_ALLOC_SYSTEM_INODE,
 493					    slot_num);
 494	if (!inode) {
 495		status = -EINVAL;
 496		mlog_errno(status);
 497		goto bail;
 498	}
 499
 500	inode_lock(inode);
 501
 502	status = ocfs2_read_inode_block_full(inode, &alloc_bh,
 503					     OCFS2_BH_IGNORE_CACHE);
 504	if (status < 0) {
 505		mlog_errno(status);
 506		goto bail;
 507	}
 508
 509	*alloc_copy = kmalloc(alloc_bh->b_size, GFP_KERNEL);
 510	if (!(*alloc_copy)) {
 511		status = -ENOMEM;
 512		goto bail;
 513	}
 514	memcpy((*alloc_copy), alloc_bh->b_data, alloc_bh->b_size);
 515
 516	alloc = (struct ocfs2_dinode *) alloc_bh->b_data;
 517	ocfs2_clear_local_alloc(alloc);
 518
 519	ocfs2_compute_meta_ecc(osb->sb, alloc_bh->b_data, &alloc->i_check);
 520	status = ocfs2_write_block(osb, alloc_bh, INODE_CACHE(inode));
 521	if (status < 0)
 522		mlog_errno(status);
 523
 524bail:
 525	if (status < 0) {
 526		kfree(*alloc_copy);
 527		*alloc_copy = NULL;
 528	}
 529
 530	brelse(alloc_bh);
 531
 532	if (inode) {
 533		inode_unlock(inode);
 534		iput(inode);
 535	}
 536
 537	if (status)
 538		mlog_errno(status);
 539	return status;
 540}
 541
 542/*
 543 * Step 2: By now, we've completed the journal recovery, we've stamped
 544 * a clean local alloc on disk and dropped the node out of the
 545 * recovery map. Dlm locks will no longer stall, so lets clear out the
 546 * main bitmap.
 547 */
 548int ocfs2_complete_local_alloc_recovery(struct ocfs2_super *osb,
 549					struct ocfs2_dinode *alloc)
 550{
 551	int status;
 552	handle_t *handle;
 553	struct buffer_head *main_bm_bh = NULL;
 554	struct inode *main_bm_inode;
 555
 556	main_bm_inode = ocfs2_get_system_file_inode(osb,
 557						    GLOBAL_BITMAP_SYSTEM_INODE,
 558						    OCFS2_INVALID_SLOT);
 559	if (!main_bm_inode) {
 560		status = -EINVAL;
 561		mlog_errno(status);
 562		goto out;
 563	}
 564
 565	inode_lock(main_bm_inode);
 566
 567	status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
 568	if (status < 0) {
 569		mlog_errno(status);
 570		goto out_mutex;
 571	}
 572
 573	handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS);
 574	if (IS_ERR(handle)) {
 575		status = PTR_ERR(handle);
 576		handle = NULL;
 577		mlog_errno(status);
 578		goto out_unlock;
 579	}
 580
 581	/* we want the bitmap change to be recorded on disk asap */
 582	handle->h_sync = 1;
 583
 584	status = ocfs2_sync_local_to_main(osb, handle, alloc,
 585					  main_bm_inode, main_bm_bh);
 586	if (status < 0)
 587		mlog_errno(status);
 588
 589	ocfs2_commit_trans(osb, handle);
 590
 591out_unlock:
 592	ocfs2_inode_unlock(main_bm_inode, 1);
 593
 594out_mutex:
 595	inode_unlock(main_bm_inode);
 596
 597	brelse(main_bm_bh);
 598
 599	iput(main_bm_inode);
 600
 601out:
 602	if (!status)
 603		ocfs2_init_steal_slots(osb);
 604	if (status)
 605		mlog_errno(status);
 606	return status;
 607}
 608
 609/*
 610 * make sure we've got at least bits_wanted contiguous bits in the
 611 * local alloc. You lose them when you drop i_mutex.
 612 *
 613 * We will add ourselves to the transaction passed in, but may start
 614 * our own in order to shift windows.
 615 */
 616int ocfs2_reserve_local_alloc_bits(struct ocfs2_super *osb,
 617				   u32 bits_wanted,
 618				   struct ocfs2_alloc_context *ac)
 619{
 620	int status;
 621	struct ocfs2_dinode *alloc;
 622	struct inode *local_alloc_inode;
 623	unsigned int free_bits;
 624
 625	BUG_ON(!ac);
 626
 627	local_alloc_inode =
 628		ocfs2_get_system_file_inode(osb,
 629					    LOCAL_ALLOC_SYSTEM_INODE,
 630					    osb->slot_num);
 631	if (!local_alloc_inode) {
 632		status = -ENOENT;
 633		mlog_errno(status);
 634		goto bail;
 635	}
 636
 637	inode_lock(local_alloc_inode);
 638
 639	/*
 640	 * We must double check state and allocator bits because
 641	 * another process may have changed them while holding i_mutex.
 642	 */
 643	spin_lock(&osb->osb_lock);
 644	if (!ocfs2_la_state_enabled(osb) ||
 645	    (bits_wanted > osb->local_alloc_bits)) {
 646		spin_unlock(&osb->osb_lock);
 647		status = -ENOSPC;
 648		goto bail;
 649	}
 650	spin_unlock(&osb->osb_lock);
 651
 652	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 653
 654#ifdef CONFIG_OCFS2_DEBUG_FS
 655	if (le32_to_cpu(alloc->id1.bitmap1.i_used) !=
 656	    ocfs2_local_alloc_count_bits(alloc)) {
 657		status = ocfs2_error(osb->sb, "local alloc inode %llu says it has %u used bits, but a count shows %u\n",
 658				(unsigned long long)le64_to_cpu(alloc->i_blkno),
 659				le32_to_cpu(alloc->id1.bitmap1.i_used),
 660				ocfs2_local_alloc_count_bits(alloc));
 
 
 661		goto bail;
 662	}
 663#endif
 664
 665	free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) -
 666		le32_to_cpu(alloc->id1.bitmap1.i_used);
 667	if (bits_wanted > free_bits) {
 668		/* uhoh, window change time. */
 669		status =
 670			ocfs2_local_alloc_slide_window(osb, local_alloc_inode);
 671		if (status < 0) {
 672			if (status != -ENOSPC)
 673				mlog_errno(status);
 674			goto bail;
 675		}
 676
 677		/*
 678		 * Under certain conditions, the window slide code
 679		 * might have reduced the number of bits available or
 680		 * disabled the the local alloc entirely. Re-check
 681		 * here and return -ENOSPC if necessary.
 682		 */
 683		status = -ENOSPC;
 684		if (!ocfs2_la_state_enabled(osb))
 685			goto bail;
 686
 687		free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) -
 688			le32_to_cpu(alloc->id1.bitmap1.i_used);
 689		if (bits_wanted > free_bits)
 690			goto bail;
 691	}
 692
 693	ac->ac_inode = local_alloc_inode;
 694	/* We should never use localalloc from another slot */
 695	ac->ac_alloc_slot = osb->slot_num;
 696	ac->ac_which = OCFS2_AC_USE_LOCAL;
 697	get_bh(osb->local_alloc_bh);
 698	ac->ac_bh = osb->local_alloc_bh;
 699	status = 0;
 700bail:
 701	if (status < 0 && local_alloc_inode) {
 702		inode_unlock(local_alloc_inode);
 703		iput(local_alloc_inode);
 704	}
 705
 706	trace_ocfs2_reserve_local_alloc_bits(
 707		(unsigned long long)ac->ac_max_block,
 708		bits_wanted, osb->slot_num, status);
 709
 710	if (status)
 711		mlog_errno(status);
 712	return status;
 713}
 714
 715int ocfs2_claim_local_alloc_bits(struct ocfs2_super *osb,
 716				 handle_t *handle,
 717				 struct ocfs2_alloc_context *ac,
 718				 u32 bits_wanted,
 719				 u32 *bit_off,
 720				 u32 *num_bits)
 721{
 722	int status, start;
 723	struct inode *local_alloc_inode;
 724	void *bitmap;
 725	struct ocfs2_dinode *alloc;
 726	struct ocfs2_local_alloc *la;
 727
 728	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL);
 729
 730	local_alloc_inode = ac->ac_inode;
 731	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 732	la = OCFS2_LOCAL_ALLOC(alloc);
 733
 734	start = ocfs2_local_alloc_find_clear_bits(osb, alloc, &bits_wanted,
 735						  ac->ac_resv);
 736	if (start == -1) {
 737		/* TODO: Shouldn't we just BUG here? */
 738		status = -ENOSPC;
 739		mlog_errno(status);
 740		goto bail;
 741	}
 742
 743	bitmap = la->la_bitmap;
 744	*bit_off = le32_to_cpu(la->la_bm_off) + start;
 745	*num_bits = bits_wanted;
 746
 747	status = ocfs2_journal_access_di(handle,
 748					 INODE_CACHE(local_alloc_inode),
 749					 osb->local_alloc_bh,
 750					 OCFS2_JOURNAL_ACCESS_WRITE);
 751	if (status < 0) {
 752		mlog_errno(status);
 753		goto bail;
 754	}
 755
 756	ocfs2_resmap_claimed_bits(&osb->osb_la_resmap, ac->ac_resv, start,
 757				  bits_wanted);
 758
 759	while(bits_wanted--)
 760		ocfs2_set_bit(start++, bitmap);
 761
 762	le32_add_cpu(&alloc->id1.bitmap1.i_used, *num_bits);
 763	ocfs2_journal_dirty(handle, osb->local_alloc_bh);
 764
 765bail:
 766	if (status)
 767		mlog_errno(status);
 768	return status;
 769}
 770
 771int ocfs2_free_local_alloc_bits(struct ocfs2_super *osb,
 772				handle_t *handle,
 773				struct ocfs2_alloc_context *ac,
 774				u32 bit_off,
 775				u32 num_bits)
 776{
 777	int status, start;
 778	u32 clear_bits;
 779	struct inode *local_alloc_inode;
 780	void *bitmap;
 781	struct ocfs2_dinode *alloc;
 782	struct ocfs2_local_alloc *la;
 783
 784	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL);
 785
 786	local_alloc_inode = ac->ac_inode;
 787	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 788	la = OCFS2_LOCAL_ALLOC(alloc);
 789
 790	bitmap = la->la_bitmap;
 791	start = bit_off - le32_to_cpu(la->la_bm_off);
 792	clear_bits = num_bits;
 793
 794	status = ocfs2_journal_access_di(handle,
 795			INODE_CACHE(local_alloc_inode),
 796			osb->local_alloc_bh,
 797			OCFS2_JOURNAL_ACCESS_WRITE);
 798	if (status < 0) {
 799		mlog_errno(status);
 800		goto bail;
 801	}
 802
 803	while (clear_bits--)
 804		ocfs2_clear_bit(start++, bitmap);
 805
 806	le32_add_cpu(&alloc->id1.bitmap1.i_used, -num_bits);
 807	ocfs2_journal_dirty(handle, osb->local_alloc_bh);
 808
 809bail:
 810	return status;
 811}
 812
 813static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc)
 814{
 815	u32 count;
 816	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
 817
 818	count = memweight(la->la_bitmap, le16_to_cpu(la->la_size));
 819
 820	trace_ocfs2_local_alloc_count_bits(count);
 821	return count;
 822}
 823
 824static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb,
 825				     struct ocfs2_dinode *alloc,
 826				     u32 *numbits,
 827				     struct ocfs2_alloc_reservation *resv)
 828{
 829	int numfound = 0, bitoff, left, startoff;
 830	int local_resv = 0;
 831	struct ocfs2_alloc_reservation r;
 832	void *bitmap = NULL;
 833	struct ocfs2_reservation_map *resmap = &osb->osb_la_resmap;
 834
 835	if (!alloc->id1.bitmap1.i_total) {
 836		bitoff = -1;
 837		goto bail;
 838	}
 839
 840	if (!resv) {
 841		local_resv = 1;
 842		ocfs2_resv_init_once(&r);
 843		ocfs2_resv_set_type(&r, OCFS2_RESV_FLAG_TMP);
 844		resv = &r;
 845	}
 846
 847	numfound = *numbits;
 848	if (ocfs2_resmap_resv_bits(resmap, resv, &bitoff, &numfound) == 0) {
 849		if (numfound < *numbits)
 850			*numbits = numfound;
 851		goto bail;
 852	}
 853
 854	/*
 855	 * Code error. While reservations are enabled, local
 856	 * allocation should _always_ go through them.
 857	 */
 858	BUG_ON(osb->osb_resv_level != 0);
 859
 860	/*
 861	 * Reservations are disabled. Handle this the old way.
 862	 */
 863
 864	bitmap = OCFS2_LOCAL_ALLOC(alloc)->la_bitmap;
 865
 866	numfound = bitoff = startoff = 0;
 
 867	left = le32_to_cpu(alloc->id1.bitmap1.i_total);
 868	while ((bitoff = ocfs2_find_next_zero_bit(bitmap, left, startoff)) != -1) {
 869		if (bitoff == left) {
 870			/* mlog(0, "bitoff (%d) == left", bitoff); */
 871			break;
 872		}
 873		/* mlog(0, "Found a zero: bitoff = %d, startoff = %d, "
 874		   "numfound = %d\n", bitoff, startoff, numfound);*/
 875
 876		/* Ok, we found a zero bit... is it contig. or do we
 877		 * start over?*/
 878		if (bitoff == startoff) {
 879			/* we found a zero */
 880			numfound++;
 881			startoff++;
 882		} else {
 883			/* got a zero after some ones */
 884			numfound = 1;
 885			startoff = bitoff+1;
 886		}
 887		/* we got everything we needed */
 888		if (numfound == *numbits) {
 889			/* mlog(0, "Found it all!\n"); */
 890			break;
 891		}
 892	}
 893
 894	trace_ocfs2_local_alloc_find_clear_bits_search_bitmap(bitoff, numfound);
 895
 896	if (numfound == *numbits)
 897		bitoff = startoff - numfound;
 898	else
 899		bitoff = -1;
 900
 901bail:
 902	if (local_resv)
 903		ocfs2_resv_discard(resmap, resv);
 904
 905	trace_ocfs2_local_alloc_find_clear_bits(*numbits,
 906		le32_to_cpu(alloc->id1.bitmap1.i_total),
 907		bitoff, numfound);
 908
 909	return bitoff;
 910}
 911
 912static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc)
 913{
 914	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
 915	int i;
 916
 917	alloc->id1.bitmap1.i_total = 0;
 918	alloc->id1.bitmap1.i_used = 0;
 919	la->la_bm_off = 0;
 920	for(i = 0; i < le16_to_cpu(la->la_size); i++)
 921		la->la_bitmap[i] = 0;
 922}
 923
 924#if 0
 925/* turn this on and uncomment below to aid debugging window shifts. */
 926static void ocfs2_verify_zero_bits(unsigned long *bitmap,
 927				   unsigned int start,
 928				   unsigned int count)
 929{
 930	unsigned int tmp = count;
 931	while(tmp--) {
 932		if (ocfs2_test_bit(start + tmp, bitmap)) {
 933			printk("ocfs2_verify_zero_bits: start = %u, count = "
 934			       "%u\n", start, count);
 935			printk("ocfs2_verify_zero_bits: bit %u is set!",
 936			       start + tmp);
 937			BUG();
 938		}
 939	}
 940}
 941#endif
 942
 943/*
 944 * sync the local alloc to main bitmap.
 945 *
 946 * assumes you've already locked the main bitmap -- the bitmap inode
 947 * passed is used for caching.
 948 */
 949static int ocfs2_sync_local_to_main(struct ocfs2_super *osb,
 950				    handle_t *handle,
 951				    struct ocfs2_dinode *alloc,
 952				    struct inode *main_bm_inode,
 953				    struct buffer_head *main_bm_bh)
 954{
 955	int status = 0;
 956	int bit_off, left, count, start;
 957	u64 la_start_blk;
 958	u64 blkno;
 959	void *bitmap;
 960	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
 961
 962	trace_ocfs2_sync_local_to_main(
 963	     le32_to_cpu(alloc->id1.bitmap1.i_total),
 964	     le32_to_cpu(alloc->id1.bitmap1.i_used));
 965
 966	if (!alloc->id1.bitmap1.i_total) {
 967		goto bail;
 968	}
 969
 970	if (le32_to_cpu(alloc->id1.bitmap1.i_used) ==
 971	    le32_to_cpu(alloc->id1.bitmap1.i_total)) {
 972		goto bail;
 973	}
 974
 975	la_start_blk = ocfs2_clusters_to_blocks(osb->sb,
 976						le32_to_cpu(la->la_bm_off));
 977	bitmap = la->la_bitmap;
 978	start = count = bit_off = 0;
 979	left = le32_to_cpu(alloc->id1.bitmap1.i_total);
 980
 981	while ((bit_off = ocfs2_find_next_zero_bit(bitmap, left, start))
 982	       != -1) {
 983		if ((bit_off < left) && (bit_off == start)) {
 984			count++;
 985			start++;
 986			continue;
 987		}
 988		if (count) {
 989			blkno = la_start_blk +
 990				ocfs2_clusters_to_blocks(osb->sb,
 991							 start - count);
 992
 993			trace_ocfs2_sync_local_to_main_free(
 994			     count, start - count,
 995			     (unsigned long long)la_start_blk,
 996			     (unsigned long long)blkno);
 997
 998			status = ocfs2_release_clusters(handle,
 999							main_bm_inode,
1000							main_bm_bh, blkno,
1001							count);
1002			if (status < 0) {
1003				mlog_errno(status);
1004				goto bail;
1005			}
1006		}
1007		if (bit_off >= left)
1008			break;
1009		count = 1;
1010		start = bit_off + 1;
1011	}
1012
1013bail:
1014	if (status)
1015		mlog_errno(status);
1016	return status;
1017}
1018
1019enum ocfs2_la_event {
1020	OCFS2_LA_EVENT_SLIDE,		/* Normal window slide. */
1021	OCFS2_LA_EVENT_FRAGMENTED,	/* The global bitmap has
1022					 * enough bits theoretically
1023					 * free, but a contiguous
1024					 * allocation could not be
1025					 * found. */
1026	OCFS2_LA_EVENT_ENOSPC,		/* Global bitmap doesn't have
1027					 * enough bits free to satisfy
1028					 * our request. */
1029};
1030#define OCFS2_LA_ENABLE_INTERVAL (30 * HZ)
1031/*
1032 * Given an event, calculate the size of our next local alloc window.
1033 *
1034 * This should always be called under i_mutex of the local alloc inode
1035 * so that local alloc disabling doesn't race with processes trying to
1036 * use the allocator.
1037 *
1038 * Returns the state which the local alloc was left in. This value can
1039 * be ignored by some paths.
1040 */
1041static int ocfs2_recalc_la_window(struct ocfs2_super *osb,
1042				  enum ocfs2_la_event event)
1043{
1044	unsigned int bits;
1045	int state;
1046
1047	spin_lock(&osb->osb_lock);
1048	if (osb->local_alloc_state == OCFS2_LA_DISABLED) {
1049		WARN_ON_ONCE(osb->local_alloc_state == OCFS2_LA_DISABLED);
1050		goto out_unlock;
1051	}
1052
1053	/*
1054	 * ENOSPC and fragmentation are treated similarly for now.
1055	 */
1056	if (event == OCFS2_LA_EVENT_ENOSPC ||
1057	    event == OCFS2_LA_EVENT_FRAGMENTED) {
1058		/*
1059		 * We ran out of contiguous space in the primary
1060		 * bitmap. Drastically reduce the number of bits used
1061		 * by local alloc until we have to disable it.
1062		 */
1063		bits = osb->local_alloc_bits >> 1;
1064		if (bits > ocfs2_megabytes_to_clusters(osb->sb, 1)) {
1065			/*
1066			 * By setting state to THROTTLED, we'll keep
1067			 * the number of local alloc bits used down
1068			 * until an event occurs which would give us
1069			 * reason to assume the bitmap situation might
1070			 * have changed.
1071			 */
1072			osb->local_alloc_state = OCFS2_LA_THROTTLED;
1073			osb->local_alloc_bits = bits;
1074		} else {
1075			osb->local_alloc_state = OCFS2_LA_DISABLED;
1076		}
1077		queue_delayed_work(osb->ocfs2_wq, &osb->la_enable_wq,
1078				   OCFS2_LA_ENABLE_INTERVAL);
1079		goto out_unlock;
1080	}
1081
1082	/*
1083	 * Don't increase the size of the local alloc window until we
1084	 * know we might be able to fulfill the request. Otherwise, we
1085	 * risk bouncing around the global bitmap during periods of
1086	 * low space.
1087	 */
1088	if (osb->local_alloc_state != OCFS2_LA_THROTTLED)
1089		osb->local_alloc_bits = osb->local_alloc_default_bits;
1090
1091out_unlock:
1092	state = osb->local_alloc_state;
1093	spin_unlock(&osb->osb_lock);
1094
1095	return state;
1096}
1097
1098static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb,
1099						struct ocfs2_alloc_context **ac,
1100						struct inode **bitmap_inode,
1101						struct buffer_head **bitmap_bh)
1102{
1103	int status;
1104
1105	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1106	if (!(*ac)) {
1107		status = -ENOMEM;
1108		mlog_errno(status);
1109		goto bail;
1110	}
1111
1112retry_enospc:
1113	(*ac)->ac_bits_wanted = osb->local_alloc_bits;
1114	status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
1115	if (status == -ENOSPC) {
1116		if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_ENOSPC) ==
1117		    OCFS2_LA_DISABLED)
1118			goto bail;
1119
1120		ocfs2_free_ac_resource(*ac);
1121		memset(*ac, 0, sizeof(struct ocfs2_alloc_context));
1122		goto retry_enospc;
1123	}
1124	if (status < 0) {
1125		mlog_errno(status);
1126		goto bail;
1127	}
1128
1129	*bitmap_inode = (*ac)->ac_inode;
1130	igrab(*bitmap_inode);
1131	*bitmap_bh = (*ac)->ac_bh;
1132	get_bh(*bitmap_bh);
1133	status = 0;
1134bail:
1135	if ((status < 0) && *ac) {
1136		ocfs2_free_alloc_context(*ac);
1137		*ac = NULL;
1138	}
1139
1140	if (status)
1141		mlog_errno(status);
1142	return status;
1143}
1144
1145/*
1146 * pass it the bitmap lock in lock_bh if you have it.
1147 */
1148static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb,
1149					handle_t *handle,
1150					struct ocfs2_alloc_context *ac)
1151{
1152	int status = 0;
1153	u32 cluster_off, cluster_count;
1154	struct ocfs2_dinode *alloc = NULL;
1155	struct ocfs2_local_alloc *la;
1156
1157	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
1158	la = OCFS2_LOCAL_ALLOC(alloc);
1159
1160	trace_ocfs2_local_alloc_new_window(
1161		le32_to_cpu(alloc->id1.bitmap1.i_total),
1162		osb->local_alloc_bits);
1163
1164	/* Instruct the allocation code to try the most recently used
1165	 * cluster group. We'll re-record the group used this pass
1166	 * below. */
1167	ac->ac_last_group = osb->la_last_gd;
1168
1169	/* we used the generic suballoc reserve function, but we set
1170	 * everything up nicely, so there's no reason why we can't use
1171	 * the more specific cluster api to claim bits. */
1172	status = ocfs2_claim_clusters(handle, ac, osb->local_alloc_bits,
1173				      &cluster_off, &cluster_count);
1174	if (status == -ENOSPC) {
1175retry_enospc:
1176		/*
1177		 * Note: We could also try syncing the journal here to
1178		 * allow use of any free bits which the current
1179		 * transaction can't give us access to. --Mark
1180		 */
1181		if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_FRAGMENTED) ==
1182		    OCFS2_LA_DISABLED)
1183			goto bail;
1184
1185		ac->ac_bits_wanted = osb->local_alloc_bits;
1186		status = ocfs2_claim_clusters(handle, ac,
1187					      osb->local_alloc_bits,
1188					      &cluster_off,
1189					      &cluster_count);
1190		if (status == -ENOSPC)
1191			goto retry_enospc;
1192		/*
1193		 * We only shrunk the *minimum* number of in our
1194		 * request - it's entirely possible that the allocator
1195		 * might give us more than we asked for.
1196		 */
1197		if (status == 0) {
1198			spin_lock(&osb->osb_lock);
1199			osb->local_alloc_bits = cluster_count;
1200			spin_unlock(&osb->osb_lock);
1201		}
1202	}
1203	if (status < 0) {
1204		if (status != -ENOSPC)
1205			mlog_errno(status);
1206		goto bail;
1207	}
1208
1209	osb->la_last_gd = ac->ac_last_group;
1210
1211	la->la_bm_off = cpu_to_le32(cluster_off);
1212	alloc->id1.bitmap1.i_total = cpu_to_le32(cluster_count);
1213	/* just in case... In the future when we find space ourselves,
1214	 * we don't have to get all contiguous -- but we'll have to
1215	 * set all previously used bits in bitmap and update
1216	 * la_bits_set before setting the bits in the main bitmap. */
1217	alloc->id1.bitmap1.i_used = 0;
1218	memset(OCFS2_LOCAL_ALLOC(alloc)->la_bitmap, 0,
1219	       le16_to_cpu(la->la_size));
1220
1221	ocfs2_resmap_restart(&osb->osb_la_resmap, cluster_count,
1222			     OCFS2_LOCAL_ALLOC(alloc)->la_bitmap);
1223
1224	trace_ocfs2_local_alloc_new_window_result(
1225		OCFS2_LOCAL_ALLOC(alloc)->la_bm_off,
1226		le32_to_cpu(alloc->id1.bitmap1.i_total));
1227
1228bail:
1229	if (status)
1230		mlog_errno(status);
1231	return status;
1232}
1233
1234/* Note that we do *NOT* lock the local alloc inode here as
1235 * it's been locked already for us. */
1236static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb,
1237					  struct inode *local_alloc_inode)
1238{
1239	int status = 0;
1240	struct buffer_head *main_bm_bh = NULL;
1241	struct inode *main_bm_inode = NULL;
1242	handle_t *handle = NULL;
1243	struct ocfs2_dinode *alloc;
1244	struct ocfs2_dinode *alloc_copy = NULL;
1245	struct ocfs2_alloc_context *ac = NULL;
1246
1247	ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_SLIDE);
1248
1249	/* This will lock the main bitmap for us. */
1250	status = ocfs2_local_alloc_reserve_for_window(osb,
1251						      &ac,
1252						      &main_bm_inode,
1253						      &main_bm_bh);
1254	if (status < 0) {
1255		if (status != -ENOSPC)
1256			mlog_errno(status);
1257		goto bail;
1258	}
1259
1260	handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS);
1261	if (IS_ERR(handle)) {
1262		status = PTR_ERR(handle);
1263		handle = NULL;
1264		mlog_errno(status);
1265		goto bail;
1266	}
1267
1268	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
1269
1270	/* We want to clear the local alloc before doing anything
1271	 * else, so that if we error later during this operation,
1272	 * local alloc shutdown won't try to double free main bitmap
1273	 * bits. Make a copy so the sync function knows which bits to
1274	 * free. */
1275	alloc_copy = kmemdup(alloc, osb->local_alloc_bh->b_size, GFP_NOFS);
1276	if (!alloc_copy) {
1277		status = -ENOMEM;
1278		mlog_errno(status);
1279		goto bail;
1280	}
 
1281
1282	status = ocfs2_journal_access_di(handle,
1283					 INODE_CACHE(local_alloc_inode),
1284					 osb->local_alloc_bh,
1285					 OCFS2_JOURNAL_ACCESS_WRITE);
1286	if (status < 0) {
1287		mlog_errno(status);
1288		goto bail;
1289	}
1290
1291	ocfs2_clear_local_alloc(alloc);
1292	ocfs2_journal_dirty(handle, osb->local_alloc_bh);
1293
1294	status = ocfs2_sync_local_to_main(osb, handle, alloc_copy,
1295					  main_bm_inode, main_bm_bh);
1296	if (status < 0) {
1297		mlog_errno(status);
1298		goto bail;
1299	}
1300
1301	status = ocfs2_local_alloc_new_window(osb, handle, ac);
1302	if (status < 0) {
1303		if (status != -ENOSPC)
1304			mlog_errno(status);
1305		goto bail;
1306	}
1307
1308	atomic_inc(&osb->alloc_stats.moves);
1309
1310bail:
1311	if (handle)
1312		ocfs2_commit_trans(osb, handle);
1313
1314	brelse(main_bm_bh);
1315
1316	iput(main_bm_inode);
 
 
1317	kfree(alloc_copy);
1318
1319	if (ac)
1320		ocfs2_free_alloc_context(ac);
1321
1322	if (status)
1323		mlog_errno(status);
1324	return status;
1325}
1326
v3.15
 
   1/* -*- mode: c; c-basic-offset: 8; -*-
   2 * vim: noexpandtab sw=8 ts=8 sts=0:
   3 *
   4 * localalloc.c
   5 *
   6 * Node local data allocation
   7 *
   8 * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
   9 *
  10 * This program is free software; you can redistribute it and/or
  11 * modify it under the terms of the GNU General Public
  12 * License as published by the Free Software Foundation; either
  13 * version 2 of the License, or (at your option) any later version.
  14 *
  15 * This program is distributed in the hope that it will be useful,
  16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18 * General Public License for more details.
  19 *
  20 * You should have received a copy of the GNU General Public
  21 * License along with this program; if not, write to the
  22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 * Boston, MA 021110-1307, USA.
  24 */
  25
  26#include <linux/fs.h>
  27#include <linux/types.h>
  28#include <linux/slab.h>
  29#include <linux/highmem.h>
  30#include <linux/bitops.h>
  31
  32#include <cluster/masklog.h>
  33
  34#include "ocfs2.h"
  35
  36#include "alloc.h"
  37#include "blockcheck.h"
  38#include "dlmglue.h"
  39#include "inode.h"
  40#include "journal.h"
  41#include "localalloc.h"
  42#include "suballoc.h"
  43#include "super.h"
  44#include "sysfile.h"
  45#include "ocfs2_trace.h"
  46
  47#include "buffer_head_io.h"
  48
  49#define OCFS2_LOCAL_ALLOC(dinode)	(&((dinode)->id2.i_lab))
  50
  51static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc);
  52
  53static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb,
  54					     struct ocfs2_dinode *alloc,
  55					     u32 *numbits,
  56					     struct ocfs2_alloc_reservation *resv);
  57
  58static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc);
  59
  60static int ocfs2_sync_local_to_main(struct ocfs2_super *osb,
  61				    handle_t *handle,
  62				    struct ocfs2_dinode *alloc,
  63				    struct inode *main_bm_inode,
  64				    struct buffer_head *main_bm_bh);
  65
  66static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb,
  67						struct ocfs2_alloc_context **ac,
  68						struct inode **bitmap_inode,
  69						struct buffer_head **bitmap_bh);
  70
  71static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb,
  72					handle_t *handle,
  73					struct ocfs2_alloc_context *ac);
  74
  75static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb,
  76					  struct inode *local_alloc_inode);
  77
  78/*
  79 * ocfs2_la_default_mb() - determine a default size, in megabytes of
  80 * the local alloc.
  81 *
  82 * Generally, we'd like to pick as large a local alloc as
  83 * possible. Performance on large workloads tends to scale
  84 * proportionally to la size. In addition to that, the reservations
  85 * code functions more efficiently as it can reserve more windows for
  86 * write.
  87 *
  88 * Some things work against us when trying to choose a large local alloc:
  89 *
  90 * - We need to ensure our sizing is picked to leave enough space in
  91 *   group descriptors for other allocations (such as block groups,
  92 *   etc). Picking default sizes which are a multiple of 4 could help
  93 *   - block groups are allocated in 2mb and 4mb chunks.
  94 *
  95 * - Likewise, we don't want to starve other nodes of bits on small
  96 *   file systems. This can easily be taken care of by limiting our
  97 *   default to a reasonable size (256M) on larger cluster sizes.
  98 *
  99 * - Some file systems can't support very large sizes - 4k and 8k in
 100 *   particular are limited to less than 128 and 256 megabytes respectively.
 101 *
 102 * The following reference table shows group descriptor and local
 103 * alloc maximums at various cluster sizes (4k blocksize)
 104 *
 105 * csize: 4K	group: 126M	la: 121M
 106 * csize: 8K	group: 252M	la: 243M
 107 * csize: 16K	group: 504M	la: 486M
 108 * csize: 32K	group: 1008M	la: 972M
 109 * csize: 64K	group: 2016M	la: 1944M
 110 * csize: 128K	group: 4032M	la: 3888M
 111 * csize: 256K	group: 8064M	la: 7776M
 112 * csize: 512K	group: 16128M	la: 15552M
 113 * csize: 1024K	group: 32256M	la: 31104M
 114 */
 115#define	OCFS2_LA_MAX_DEFAULT_MB	256
 116#define	OCFS2_LA_OLD_DEFAULT	8
 117unsigned int ocfs2_la_default_mb(struct ocfs2_super *osb)
 118{
 119	unsigned int la_mb;
 120	unsigned int gd_mb;
 121	unsigned int la_max_mb;
 122	unsigned int megs_per_slot;
 123	struct super_block *sb = osb->sb;
 124
 125	gd_mb = ocfs2_clusters_to_megabytes(osb->sb,
 126		8 * ocfs2_group_bitmap_size(sb, 0, osb->s_feature_incompat));
 127
 128	/*
 129	 * This takes care of files systems with very small group
 130	 * descriptors - 512 byte blocksize at cluster sizes lower
 131	 * than 16K and also 1k blocksize with 4k cluster size.
 132	 */
 133	if ((sb->s_blocksize == 512 && osb->s_clustersize <= 8192)
 134	    || (sb->s_blocksize == 1024 && osb->s_clustersize == 4096))
 135		return OCFS2_LA_OLD_DEFAULT;
 136
 137	/*
 138	 * Leave enough room for some block groups and make the final
 139	 * value we work from a multiple of 4.
 140	 */
 141	gd_mb -= 16;
 142	gd_mb &= 0xFFFFFFFB;
 143
 144	la_mb = gd_mb;
 145
 146	/*
 147	 * Keep window sizes down to a reasonable default
 148	 */
 149	if (la_mb > OCFS2_LA_MAX_DEFAULT_MB) {
 150		/*
 151		 * Some clustersize / blocksize combinations will have
 152		 * given us a larger than OCFS2_LA_MAX_DEFAULT_MB
 153		 * default size, but get poor distribution when
 154		 * limited to exactly 256 megabytes.
 155		 *
 156		 * As an example, 16K clustersize at 4K blocksize
 157		 * gives us a cluster group size of 504M. Paring the
 158		 * local alloc size down to 256 however, would give us
 159		 * only one window and around 200MB left in the
 160		 * cluster group. Instead, find the first size below
 161		 * 256 which would give us an even distribution.
 162		 *
 163		 * Larger cluster group sizes actually work out pretty
 164		 * well when pared to 256, so we don't have to do this
 165		 * for any group that fits more than two
 166		 * OCFS2_LA_MAX_DEFAULT_MB windows.
 167		 */
 168		if (gd_mb > (2 * OCFS2_LA_MAX_DEFAULT_MB))
 169			la_mb = 256;
 170		else {
 171			unsigned int gd_mult = gd_mb;
 172
 173			while (gd_mult > 256)
 174				gd_mult = gd_mult >> 1;
 175
 176			la_mb = gd_mult;
 177		}
 178	}
 179
 180	megs_per_slot = osb->osb_clusters_at_boot / osb->max_slots;
 181	megs_per_slot = ocfs2_clusters_to_megabytes(osb->sb, megs_per_slot);
 182	/* Too many nodes, too few disk clusters. */
 183	if (megs_per_slot < la_mb)
 184		la_mb = megs_per_slot;
 185
 186	/* We can't store more bits than we can in a block. */
 187	la_max_mb = ocfs2_clusters_to_megabytes(osb->sb,
 188						ocfs2_local_alloc_size(sb) * 8);
 189	if (la_mb > la_max_mb)
 190		la_mb = la_max_mb;
 191
 192	return la_mb;
 193}
 194
 195void ocfs2_la_set_sizes(struct ocfs2_super *osb, int requested_mb)
 196{
 197	struct super_block *sb = osb->sb;
 198	unsigned int la_default_mb = ocfs2_la_default_mb(osb);
 199	unsigned int la_max_mb;
 200
 201	la_max_mb = ocfs2_clusters_to_megabytes(sb,
 202						ocfs2_local_alloc_size(sb) * 8);
 203
 204	trace_ocfs2_la_set_sizes(requested_mb, la_max_mb, la_default_mb);
 205
 206	if (requested_mb == -1) {
 207		/* No user request - use defaults */
 208		osb->local_alloc_default_bits =
 209			ocfs2_megabytes_to_clusters(sb, la_default_mb);
 210	} else if (requested_mb > la_max_mb) {
 211		/* Request is too big, we give the maximum available */
 212		osb->local_alloc_default_bits =
 213			ocfs2_megabytes_to_clusters(sb, la_max_mb);
 214	} else {
 215		osb->local_alloc_default_bits =
 216			ocfs2_megabytes_to_clusters(sb, requested_mb);
 217	}
 218
 219	osb->local_alloc_bits = osb->local_alloc_default_bits;
 220}
 221
 222static inline int ocfs2_la_state_enabled(struct ocfs2_super *osb)
 223{
 224	return (osb->local_alloc_state == OCFS2_LA_THROTTLED ||
 225		osb->local_alloc_state == OCFS2_LA_ENABLED);
 226}
 227
 228void ocfs2_local_alloc_seen_free_bits(struct ocfs2_super *osb,
 229				      unsigned int num_clusters)
 230{
 231	spin_lock(&osb->osb_lock);
 232	if (osb->local_alloc_state == OCFS2_LA_DISABLED ||
 233	    osb->local_alloc_state == OCFS2_LA_THROTTLED)
 234		if (num_clusters >= osb->local_alloc_default_bits) {
 235			cancel_delayed_work(&osb->la_enable_wq);
 236			osb->local_alloc_state = OCFS2_LA_ENABLED;
 237		}
 238	spin_unlock(&osb->osb_lock);
 239}
 240
 241void ocfs2_la_enable_worker(struct work_struct *work)
 242{
 243	struct ocfs2_super *osb =
 244		container_of(work, struct ocfs2_super,
 245			     la_enable_wq.work);
 246	spin_lock(&osb->osb_lock);
 247	osb->local_alloc_state = OCFS2_LA_ENABLED;
 248	spin_unlock(&osb->osb_lock);
 249}
 250
 251/*
 252 * Tell us whether a given allocation should use the local alloc
 253 * file. Otherwise, it has to go to the main bitmap.
 254 *
 255 * This function does semi-dirty reads of local alloc size and state!
 256 * This is ok however, as the values are re-checked once under mutex.
 257 */
 258int ocfs2_alloc_should_use_local(struct ocfs2_super *osb, u64 bits)
 259{
 260	int ret = 0;
 261	int la_bits;
 262
 263	spin_lock(&osb->osb_lock);
 264	la_bits = osb->local_alloc_bits;
 265
 266	if (!ocfs2_la_state_enabled(osb))
 267		goto bail;
 268
 269	/* la_bits should be at least twice the size (in clusters) of
 270	 * a new block group. We want to be sure block group
 271	 * allocations go through the local alloc, so allow an
 272	 * allocation to take up to half the bitmap. */
 273	if (bits > (la_bits / 2))
 274		goto bail;
 275
 276	ret = 1;
 277bail:
 278	trace_ocfs2_alloc_should_use_local(
 279	     (unsigned long long)bits, osb->local_alloc_state, la_bits, ret);
 280	spin_unlock(&osb->osb_lock);
 281	return ret;
 282}
 283
 284int ocfs2_load_local_alloc(struct ocfs2_super *osb)
 285{
 286	int status = 0;
 287	struct ocfs2_dinode *alloc = NULL;
 288	struct buffer_head *alloc_bh = NULL;
 289	u32 num_used;
 290	struct inode *inode = NULL;
 291	struct ocfs2_local_alloc *la;
 292
 293	if (osb->local_alloc_bits == 0)
 294		goto bail;
 295
 296	if (osb->local_alloc_bits >= osb->bitmap_cpg) {
 297		mlog(ML_NOTICE, "Requested local alloc window %d is larger "
 298		     "than max possible %u. Using defaults.\n",
 299		     osb->local_alloc_bits, (osb->bitmap_cpg - 1));
 300		osb->local_alloc_bits =
 301			ocfs2_megabytes_to_clusters(osb->sb,
 302						    ocfs2_la_default_mb(osb));
 303	}
 304
 305	/* read the alloc off disk */
 306	inode = ocfs2_get_system_file_inode(osb, LOCAL_ALLOC_SYSTEM_INODE,
 307					    osb->slot_num);
 308	if (!inode) {
 309		status = -EINVAL;
 310		mlog_errno(status);
 311		goto bail;
 312	}
 313
 314	status = ocfs2_read_inode_block_full(inode, &alloc_bh,
 315					     OCFS2_BH_IGNORE_CACHE);
 316	if (status < 0) {
 317		mlog_errno(status);
 318		goto bail;
 319	}
 320
 321	alloc = (struct ocfs2_dinode *) alloc_bh->b_data;
 322	la = OCFS2_LOCAL_ALLOC(alloc);
 323
 324	if (!(le32_to_cpu(alloc->i_flags) &
 325	    (OCFS2_LOCAL_ALLOC_FL|OCFS2_BITMAP_FL))) {
 326		mlog(ML_ERROR, "Invalid local alloc inode, %llu\n",
 327		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
 328		status = -EINVAL;
 329		goto bail;
 330	}
 331
 332	if ((la->la_size == 0) ||
 333	    (le16_to_cpu(la->la_size) > ocfs2_local_alloc_size(inode->i_sb))) {
 334		mlog(ML_ERROR, "Local alloc size is invalid (la_size = %u)\n",
 335		     le16_to_cpu(la->la_size));
 336		status = -EINVAL;
 337		goto bail;
 338	}
 339
 340	/* do a little verification. */
 341	num_used = ocfs2_local_alloc_count_bits(alloc);
 342
 343	/* hopefully the local alloc has always been recovered before
 344	 * we load it. */
 345	if (num_used
 346	    || alloc->id1.bitmap1.i_used
 347	    || alloc->id1.bitmap1.i_total
 348	    || la->la_bm_off)
 349		mlog(ML_ERROR, "Local alloc hasn't been recovered!\n"
 
 350		     "found = %u, set = %u, taken = %u, off = %u\n",
 351		     num_used, le32_to_cpu(alloc->id1.bitmap1.i_used),
 352		     le32_to_cpu(alloc->id1.bitmap1.i_total),
 353		     OCFS2_LOCAL_ALLOC(alloc)->la_bm_off);
 354
 
 
 
 
 355	osb->local_alloc_bh = alloc_bh;
 356	osb->local_alloc_state = OCFS2_LA_ENABLED;
 357
 358bail:
 359	if (status < 0)
 360		brelse(alloc_bh);
 361	if (inode)
 362		iput(inode);
 363
 364	trace_ocfs2_load_local_alloc(osb->local_alloc_bits);
 365
 366	if (status)
 367		mlog_errno(status);
 368	return status;
 369}
 370
 371/*
 372 * return any unused bits to the bitmap and write out a clean
 373 * local_alloc.
 374 *
 375 * local_alloc_bh is optional. If not passed, we will simply use the
 376 * one off osb. If you do pass it however, be warned that it *will* be
 377 * returned brelse'd and NULL'd out.*/
 378void ocfs2_shutdown_local_alloc(struct ocfs2_super *osb)
 379{
 380	int status;
 381	handle_t *handle;
 382	struct inode *local_alloc_inode = NULL;
 383	struct buffer_head *bh = NULL;
 384	struct buffer_head *main_bm_bh = NULL;
 385	struct inode *main_bm_inode = NULL;
 386	struct ocfs2_dinode *alloc_copy = NULL;
 387	struct ocfs2_dinode *alloc = NULL;
 388
 389	cancel_delayed_work(&osb->la_enable_wq);
 390	flush_workqueue(ocfs2_wq);
 
 391
 392	if (osb->local_alloc_state == OCFS2_LA_UNUSED)
 393		goto out;
 394
 395	local_alloc_inode =
 396		ocfs2_get_system_file_inode(osb,
 397					    LOCAL_ALLOC_SYSTEM_INODE,
 398					    osb->slot_num);
 399	if (!local_alloc_inode) {
 400		status = -ENOENT;
 401		mlog_errno(status);
 402		goto out;
 403	}
 404
 405	osb->local_alloc_state = OCFS2_LA_DISABLED;
 406
 407	ocfs2_resmap_uninit(&osb->osb_la_resmap);
 408
 409	main_bm_inode = ocfs2_get_system_file_inode(osb,
 410						    GLOBAL_BITMAP_SYSTEM_INODE,
 411						    OCFS2_INVALID_SLOT);
 412	if (!main_bm_inode) {
 413		status = -EINVAL;
 414		mlog_errno(status);
 415		goto out;
 416	}
 417
 418	mutex_lock(&main_bm_inode->i_mutex);
 419
 420	status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
 421	if (status < 0) {
 422		mlog_errno(status);
 423		goto out_mutex;
 424	}
 425
 426	/* WINDOW_MOVE_CREDITS is a bit heavy... */
 427	handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS);
 428	if (IS_ERR(handle)) {
 429		mlog_errno(PTR_ERR(handle));
 430		handle = NULL;
 431		goto out_unlock;
 432	}
 433
 434	bh = osb->local_alloc_bh;
 435	alloc = (struct ocfs2_dinode *) bh->b_data;
 436
 437	alloc_copy = kmalloc(bh->b_size, GFP_NOFS);
 438	if (!alloc_copy) {
 439		status = -ENOMEM;
 440		goto out_commit;
 441	}
 442	memcpy(alloc_copy, alloc, bh->b_size);
 443
 444	status = ocfs2_journal_access_di(handle, INODE_CACHE(local_alloc_inode),
 445					 bh, OCFS2_JOURNAL_ACCESS_WRITE);
 446	if (status < 0) {
 447		mlog_errno(status);
 448		goto out_commit;
 449	}
 450
 451	ocfs2_clear_local_alloc(alloc);
 452	ocfs2_journal_dirty(handle, bh);
 453
 454	brelse(bh);
 455	osb->local_alloc_bh = NULL;
 456	osb->local_alloc_state = OCFS2_LA_UNUSED;
 457
 458	status = ocfs2_sync_local_to_main(osb, handle, alloc_copy,
 459					  main_bm_inode, main_bm_bh);
 460	if (status < 0)
 461		mlog_errno(status);
 462
 463out_commit:
 464	ocfs2_commit_trans(osb, handle);
 465
 466out_unlock:
 467	brelse(main_bm_bh);
 468
 469	ocfs2_inode_unlock(main_bm_inode, 1);
 470
 471out_mutex:
 472	mutex_unlock(&main_bm_inode->i_mutex);
 473	iput(main_bm_inode);
 474
 475out:
 476	if (local_alloc_inode)
 477		iput(local_alloc_inode);
 478
 479	kfree(alloc_copy);
 480}
 481
 482/*
 483 * We want to free the bitmap bits outside of any recovery context as
 484 * we'll need a cluster lock to do so, but we must clear the local
 485 * alloc before giving up the recovered nodes journal. To solve this,
 486 * we kmalloc a copy of the local alloc before it's change for the
 487 * caller to process with ocfs2_complete_local_alloc_recovery
 488 */
 489int ocfs2_begin_local_alloc_recovery(struct ocfs2_super *osb,
 490				     int slot_num,
 491				     struct ocfs2_dinode **alloc_copy)
 492{
 493	int status = 0;
 494	struct buffer_head *alloc_bh = NULL;
 495	struct inode *inode = NULL;
 496	struct ocfs2_dinode *alloc;
 497
 498	trace_ocfs2_begin_local_alloc_recovery(slot_num);
 499
 500	*alloc_copy = NULL;
 501
 502	inode = ocfs2_get_system_file_inode(osb,
 503					    LOCAL_ALLOC_SYSTEM_INODE,
 504					    slot_num);
 505	if (!inode) {
 506		status = -EINVAL;
 507		mlog_errno(status);
 508		goto bail;
 509	}
 510
 511	mutex_lock(&inode->i_mutex);
 512
 513	status = ocfs2_read_inode_block_full(inode, &alloc_bh,
 514					     OCFS2_BH_IGNORE_CACHE);
 515	if (status < 0) {
 516		mlog_errno(status);
 517		goto bail;
 518	}
 519
 520	*alloc_copy = kmalloc(alloc_bh->b_size, GFP_KERNEL);
 521	if (!(*alloc_copy)) {
 522		status = -ENOMEM;
 523		goto bail;
 524	}
 525	memcpy((*alloc_copy), alloc_bh->b_data, alloc_bh->b_size);
 526
 527	alloc = (struct ocfs2_dinode *) alloc_bh->b_data;
 528	ocfs2_clear_local_alloc(alloc);
 529
 530	ocfs2_compute_meta_ecc(osb->sb, alloc_bh->b_data, &alloc->i_check);
 531	status = ocfs2_write_block(osb, alloc_bh, INODE_CACHE(inode));
 532	if (status < 0)
 533		mlog_errno(status);
 534
 535bail:
 536	if (status < 0) {
 537		kfree(*alloc_copy);
 538		*alloc_copy = NULL;
 539	}
 540
 541	brelse(alloc_bh);
 542
 543	if (inode) {
 544		mutex_unlock(&inode->i_mutex);
 545		iput(inode);
 546	}
 547
 548	if (status)
 549		mlog_errno(status);
 550	return status;
 551}
 552
 553/*
 554 * Step 2: By now, we've completed the journal recovery, we've stamped
 555 * a clean local alloc on disk and dropped the node out of the
 556 * recovery map. Dlm locks will no longer stall, so lets clear out the
 557 * main bitmap.
 558 */
 559int ocfs2_complete_local_alloc_recovery(struct ocfs2_super *osb,
 560					struct ocfs2_dinode *alloc)
 561{
 562	int status;
 563	handle_t *handle;
 564	struct buffer_head *main_bm_bh = NULL;
 565	struct inode *main_bm_inode;
 566
 567	main_bm_inode = ocfs2_get_system_file_inode(osb,
 568						    GLOBAL_BITMAP_SYSTEM_INODE,
 569						    OCFS2_INVALID_SLOT);
 570	if (!main_bm_inode) {
 571		status = -EINVAL;
 572		mlog_errno(status);
 573		goto out;
 574	}
 575
 576	mutex_lock(&main_bm_inode->i_mutex);
 577
 578	status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
 579	if (status < 0) {
 580		mlog_errno(status);
 581		goto out_mutex;
 582	}
 583
 584	handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS);
 585	if (IS_ERR(handle)) {
 586		status = PTR_ERR(handle);
 587		handle = NULL;
 588		mlog_errno(status);
 589		goto out_unlock;
 590	}
 591
 592	/* we want the bitmap change to be recorded on disk asap */
 593	handle->h_sync = 1;
 594
 595	status = ocfs2_sync_local_to_main(osb, handle, alloc,
 596					  main_bm_inode, main_bm_bh);
 597	if (status < 0)
 598		mlog_errno(status);
 599
 600	ocfs2_commit_trans(osb, handle);
 601
 602out_unlock:
 603	ocfs2_inode_unlock(main_bm_inode, 1);
 604
 605out_mutex:
 606	mutex_unlock(&main_bm_inode->i_mutex);
 607
 608	brelse(main_bm_bh);
 609
 610	iput(main_bm_inode);
 611
 612out:
 613	if (!status)
 614		ocfs2_init_steal_slots(osb);
 615	if (status)
 616		mlog_errno(status);
 617	return status;
 618}
 619
 620/*
 621 * make sure we've got at least bits_wanted contiguous bits in the
 622 * local alloc. You lose them when you drop i_mutex.
 623 *
 624 * We will add ourselves to the transaction passed in, but may start
 625 * our own in order to shift windows.
 626 */
 627int ocfs2_reserve_local_alloc_bits(struct ocfs2_super *osb,
 628				   u32 bits_wanted,
 629				   struct ocfs2_alloc_context *ac)
 630{
 631	int status;
 632	struct ocfs2_dinode *alloc;
 633	struct inode *local_alloc_inode;
 634	unsigned int free_bits;
 635
 636	BUG_ON(!ac);
 637
 638	local_alloc_inode =
 639		ocfs2_get_system_file_inode(osb,
 640					    LOCAL_ALLOC_SYSTEM_INODE,
 641					    osb->slot_num);
 642	if (!local_alloc_inode) {
 643		status = -ENOENT;
 644		mlog_errno(status);
 645		goto bail;
 646	}
 647
 648	mutex_lock(&local_alloc_inode->i_mutex);
 649
 650	/*
 651	 * We must double check state and allocator bits because
 652	 * another process may have changed them while holding i_mutex.
 653	 */
 654	spin_lock(&osb->osb_lock);
 655	if (!ocfs2_la_state_enabled(osb) ||
 656	    (bits_wanted > osb->local_alloc_bits)) {
 657		spin_unlock(&osb->osb_lock);
 658		status = -ENOSPC;
 659		goto bail;
 660	}
 661	spin_unlock(&osb->osb_lock);
 662
 663	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 664
 665#ifdef CONFIG_OCFS2_DEBUG_FS
 666	if (le32_to_cpu(alloc->id1.bitmap1.i_used) !=
 667	    ocfs2_local_alloc_count_bits(alloc)) {
 668		ocfs2_error(osb->sb, "local alloc inode %llu says it has "
 669			    "%u free bits, but a count shows %u",
 670			    (unsigned long long)le64_to_cpu(alloc->i_blkno),
 671			    le32_to_cpu(alloc->id1.bitmap1.i_used),
 672			    ocfs2_local_alloc_count_bits(alloc));
 673		status = -EIO;
 674		goto bail;
 675	}
 676#endif
 677
 678	free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) -
 679		le32_to_cpu(alloc->id1.bitmap1.i_used);
 680	if (bits_wanted > free_bits) {
 681		/* uhoh, window change time. */
 682		status =
 683			ocfs2_local_alloc_slide_window(osb, local_alloc_inode);
 684		if (status < 0) {
 685			if (status != -ENOSPC)
 686				mlog_errno(status);
 687			goto bail;
 688		}
 689
 690		/*
 691		 * Under certain conditions, the window slide code
 692		 * might have reduced the number of bits available or
 693		 * disabled the the local alloc entirely. Re-check
 694		 * here and return -ENOSPC if necessary.
 695		 */
 696		status = -ENOSPC;
 697		if (!ocfs2_la_state_enabled(osb))
 698			goto bail;
 699
 700		free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) -
 701			le32_to_cpu(alloc->id1.bitmap1.i_used);
 702		if (bits_wanted > free_bits)
 703			goto bail;
 704	}
 705
 706	ac->ac_inode = local_alloc_inode;
 707	/* We should never use localalloc from another slot */
 708	ac->ac_alloc_slot = osb->slot_num;
 709	ac->ac_which = OCFS2_AC_USE_LOCAL;
 710	get_bh(osb->local_alloc_bh);
 711	ac->ac_bh = osb->local_alloc_bh;
 712	status = 0;
 713bail:
 714	if (status < 0 && local_alloc_inode) {
 715		mutex_unlock(&local_alloc_inode->i_mutex);
 716		iput(local_alloc_inode);
 717	}
 718
 719	trace_ocfs2_reserve_local_alloc_bits(
 720		(unsigned long long)ac->ac_max_block,
 721		bits_wanted, osb->slot_num, status);
 722
 723	if (status)
 724		mlog_errno(status);
 725	return status;
 726}
 727
 728int ocfs2_claim_local_alloc_bits(struct ocfs2_super *osb,
 729				 handle_t *handle,
 730				 struct ocfs2_alloc_context *ac,
 731				 u32 bits_wanted,
 732				 u32 *bit_off,
 733				 u32 *num_bits)
 734{
 735	int status, start;
 736	struct inode *local_alloc_inode;
 737	void *bitmap;
 738	struct ocfs2_dinode *alloc;
 739	struct ocfs2_local_alloc *la;
 740
 741	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL);
 742
 743	local_alloc_inode = ac->ac_inode;
 744	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 745	la = OCFS2_LOCAL_ALLOC(alloc);
 746
 747	start = ocfs2_local_alloc_find_clear_bits(osb, alloc, &bits_wanted,
 748						  ac->ac_resv);
 749	if (start == -1) {
 750		/* TODO: Shouldn't we just BUG here? */
 751		status = -ENOSPC;
 752		mlog_errno(status);
 753		goto bail;
 754	}
 755
 756	bitmap = la->la_bitmap;
 757	*bit_off = le32_to_cpu(la->la_bm_off) + start;
 758	*num_bits = bits_wanted;
 759
 760	status = ocfs2_journal_access_di(handle,
 761					 INODE_CACHE(local_alloc_inode),
 762					 osb->local_alloc_bh,
 763					 OCFS2_JOURNAL_ACCESS_WRITE);
 764	if (status < 0) {
 765		mlog_errno(status);
 766		goto bail;
 767	}
 768
 769	ocfs2_resmap_claimed_bits(&osb->osb_la_resmap, ac->ac_resv, start,
 770				  bits_wanted);
 771
 772	while(bits_wanted--)
 773		ocfs2_set_bit(start++, bitmap);
 774
 775	le32_add_cpu(&alloc->id1.bitmap1.i_used, *num_bits);
 776	ocfs2_journal_dirty(handle, osb->local_alloc_bh);
 777
 778bail:
 779	if (status)
 780		mlog_errno(status);
 781	return status;
 782}
 783
 784int ocfs2_free_local_alloc_bits(struct ocfs2_super *osb,
 785				handle_t *handle,
 786				struct ocfs2_alloc_context *ac,
 787				u32 bit_off,
 788				u32 num_bits)
 789{
 790	int status, start;
 791	u32 clear_bits;
 792	struct inode *local_alloc_inode;
 793	void *bitmap;
 794	struct ocfs2_dinode *alloc;
 795	struct ocfs2_local_alloc *la;
 796
 797	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL);
 798
 799	local_alloc_inode = ac->ac_inode;
 800	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
 801	la = OCFS2_LOCAL_ALLOC(alloc);
 802
 803	bitmap = la->la_bitmap;
 804	start = bit_off - le32_to_cpu(la->la_bm_off);
 805	clear_bits = num_bits;
 806
 807	status = ocfs2_journal_access_di(handle,
 808			INODE_CACHE(local_alloc_inode),
 809			osb->local_alloc_bh,
 810			OCFS2_JOURNAL_ACCESS_WRITE);
 811	if (status < 0) {
 812		mlog_errno(status);
 813		goto bail;
 814	}
 815
 816	while (clear_bits--)
 817		ocfs2_clear_bit(start++, bitmap);
 818
 819	le32_add_cpu(&alloc->id1.bitmap1.i_used, -num_bits);
 820	ocfs2_journal_dirty(handle, osb->local_alloc_bh);
 821
 822bail:
 823	return status;
 824}
 825
 826static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc)
 827{
 828	u32 count;
 829	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
 830
 831	count = memweight(la->la_bitmap, le16_to_cpu(la->la_size));
 832
 833	trace_ocfs2_local_alloc_count_bits(count);
 834	return count;
 835}
 836
 837static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb,
 838				     struct ocfs2_dinode *alloc,
 839				     u32 *numbits,
 840				     struct ocfs2_alloc_reservation *resv)
 841{
 842	int numfound, bitoff, left, startoff, lastzero;
 843	int local_resv = 0;
 844	struct ocfs2_alloc_reservation r;
 845	void *bitmap = NULL;
 846	struct ocfs2_reservation_map *resmap = &osb->osb_la_resmap;
 847
 848	if (!alloc->id1.bitmap1.i_total) {
 849		bitoff = -1;
 850		goto bail;
 851	}
 852
 853	if (!resv) {
 854		local_resv = 1;
 855		ocfs2_resv_init_once(&r);
 856		ocfs2_resv_set_type(&r, OCFS2_RESV_FLAG_TMP);
 857		resv = &r;
 858	}
 859
 860	numfound = *numbits;
 861	if (ocfs2_resmap_resv_bits(resmap, resv, &bitoff, &numfound) == 0) {
 862		if (numfound < *numbits)
 863			*numbits = numfound;
 864		goto bail;
 865	}
 866
 867	/*
 868	 * Code error. While reservations are enabled, local
 869	 * allocation should _always_ go through them.
 870	 */
 871	BUG_ON(osb->osb_resv_level != 0);
 872
 873	/*
 874	 * Reservations are disabled. Handle this the old way.
 875	 */
 876
 877	bitmap = OCFS2_LOCAL_ALLOC(alloc)->la_bitmap;
 878
 879	numfound = bitoff = startoff = 0;
 880	lastzero = -1;
 881	left = le32_to_cpu(alloc->id1.bitmap1.i_total);
 882	while ((bitoff = ocfs2_find_next_zero_bit(bitmap, left, startoff)) != -1) {
 883		if (bitoff == left) {
 884			/* mlog(0, "bitoff (%d) == left", bitoff); */
 885			break;
 886		}
 887		/* mlog(0, "Found a zero: bitoff = %d, startoff = %d, "
 888		   "numfound = %d\n", bitoff, startoff, numfound);*/
 889
 890		/* Ok, we found a zero bit... is it contig. or do we
 891		 * start over?*/
 892		if (bitoff == startoff) {
 893			/* we found a zero */
 894			numfound++;
 895			startoff++;
 896		} else {
 897			/* got a zero after some ones */
 898			numfound = 1;
 899			startoff = bitoff+1;
 900		}
 901		/* we got everything we needed */
 902		if (numfound == *numbits) {
 903			/* mlog(0, "Found it all!\n"); */
 904			break;
 905		}
 906	}
 907
 908	trace_ocfs2_local_alloc_find_clear_bits_search_bitmap(bitoff, numfound);
 909
 910	if (numfound == *numbits)
 911		bitoff = startoff - numfound;
 912	else
 913		bitoff = -1;
 914
 915bail:
 916	if (local_resv)
 917		ocfs2_resv_discard(resmap, resv);
 918
 919	trace_ocfs2_local_alloc_find_clear_bits(*numbits,
 920		le32_to_cpu(alloc->id1.bitmap1.i_total),
 921		bitoff, numfound);
 922
 923	return bitoff;
 924}
 925
 926static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc)
 927{
 928	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
 929	int i;
 930
 931	alloc->id1.bitmap1.i_total = 0;
 932	alloc->id1.bitmap1.i_used = 0;
 933	la->la_bm_off = 0;
 934	for(i = 0; i < le16_to_cpu(la->la_size); i++)
 935		la->la_bitmap[i] = 0;
 936}
 937
 938#if 0
 939/* turn this on and uncomment below to aid debugging window shifts. */
 940static void ocfs2_verify_zero_bits(unsigned long *bitmap,
 941				   unsigned int start,
 942				   unsigned int count)
 943{
 944	unsigned int tmp = count;
 945	while(tmp--) {
 946		if (ocfs2_test_bit(start + tmp, bitmap)) {
 947			printk("ocfs2_verify_zero_bits: start = %u, count = "
 948			       "%u\n", start, count);
 949			printk("ocfs2_verify_zero_bits: bit %u is set!",
 950			       start + tmp);
 951			BUG();
 952		}
 953	}
 954}
 955#endif
 956
 957/*
 958 * sync the local alloc to main bitmap.
 959 *
 960 * assumes you've already locked the main bitmap -- the bitmap inode
 961 * passed is used for caching.
 962 */
 963static int ocfs2_sync_local_to_main(struct ocfs2_super *osb,
 964				    handle_t *handle,
 965				    struct ocfs2_dinode *alloc,
 966				    struct inode *main_bm_inode,
 967				    struct buffer_head *main_bm_bh)
 968{
 969	int status = 0;
 970	int bit_off, left, count, start;
 971	u64 la_start_blk;
 972	u64 blkno;
 973	void *bitmap;
 974	struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc);
 975
 976	trace_ocfs2_sync_local_to_main(
 977	     le32_to_cpu(alloc->id1.bitmap1.i_total),
 978	     le32_to_cpu(alloc->id1.bitmap1.i_used));
 979
 980	if (!alloc->id1.bitmap1.i_total) {
 981		goto bail;
 982	}
 983
 984	if (le32_to_cpu(alloc->id1.bitmap1.i_used) ==
 985	    le32_to_cpu(alloc->id1.bitmap1.i_total)) {
 986		goto bail;
 987	}
 988
 989	la_start_blk = ocfs2_clusters_to_blocks(osb->sb,
 990						le32_to_cpu(la->la_bm_off));
 991	bitmap = la->la_bitmap;
 992	start = count = bit_off = 0;
 993	left = le32_to_cpu(alloc->id1.bitmap1.i_total);
 994
 995	while ((bit_off = ocfs2_find_next_zero_bit(bitmap, left, start))
 996	       != -1) {
 997		if ((bit_off < left) && (bit_off == start)) {
 998			count++;
 999			start++;
1000			continue;
1001		}
1002		if (count) {
1003			blkno = la_start_blk +
1004				ocfs2_clusters_to_blocks(osb->sb,
1005							 start - count);
1006
1007			trace_ocfs2_sync_local_to_main_free(
1008			     count, start - count,
1009			     (unsigned long long)la_start_blk,
1010			     (unsigned long long)blkno);
1011
1012			status = ocfs2_release_clusters(handle,
1013							main_bm_inode,
1014							main_bm_bh, blkno,
1015							count);
1016			if (status < 0) {
1017				mlog_errno(status);
1018				goto bail;
1019			}
1020		}
1021		if (bit_off >= left)
1022			break;
1023		count = 1;
1024		start = bit_off + 1;
1025	}
1026
1027bail:
1028	if (status)
1029		mlog_errno(status);
1030	return status;
1031}
1032
1033enum ocfs2_la_event {
1034	OCFS2_LA_EVENT_SLIDE,		/* Normal window slide. */
1035	OCFS2_LA_EVENT_FRAGMENTED,	/* The global bitmap has
1036					 * enough bits theoretically
1037					 * free, but a contiguous
1038					 * allocation could not be
1039					 * found. */
1040	OCFS2_LA_EVENT_ENOSPC,		/* Global bitmap doesn't have
1041					 * enough bits free to satisfy
1042					 * our request. */
1043};
1044#define OCFS2_LA_ENABLE_INTERVAL (30 * HZ)
1045/*
1046 * Given an event, calculate the size of our next local alloc window.
1047 *
1048 * This should always be called under i_mutex of the local alloc inode
1049 * so that local alloc disabling doesn't race with processes trying to
1050 * use the allocator.
1051 *
1052 * Returns the state which the local alloc was left in. This value can
1053 * be ignored by some paths.
1054 */
1055static int ocfs2_recalc_la_window(struct ocfs2_super *osb,
1056				  enum ocfs2_la_event event)
1057{
1058	unsigned int bits;
1059	int state;
1060
1061	spin_lock(&osb->osb_lock);
1062	if (osb->local_alloc_state == OCFS2_LA_DISABLED) {
1063		WARN_ON_ONCE(osb->local_alloc_state == OCFS2_LA_DISABLED);
1064		goto out_unlock;
1065	}
1066
1067	/*
1068	 * ENOSPC and fragmentation are treated similarly for now.
1069	 */
1070	if (event == OCFS2_LA_EVENT_ENOSPC ||
1071	    event == OCFS2_LA_EVENT_FRAGMENTED) {
1072		/*
1073		 * We ran out of contiguous space in the primary
1074		 * bitmap. Drastically reduce the number of bits used
1075		 * by local alloc until we have to disable it.
1076		 */
1077		bits = osb->local_alloc_bits >> 1;
1078		if (bits > ocfs2_megabytes_to_clusters(osb->sb, 1)) {
1079			/*
1080			 * By setting state to THROTTLED, we'll keep
1081			 * the number of local alloc bits used down
1082			 * until an event occurs which would give us
1083			 * reason to assume the bitmap situation might
1084			 * have changed.
1085			 */
1086			osb->local_alloc_state = OCFS2_LA_THROTTLED;
1087			osb->local_alloc_bits = bits;
1088		} else {
1089			osb->local_alloc_state = OCFS2_LA_DISABLED;
1090		}
1091		queue_delayed_work(ocfs2_wq, &osb->la_enable_wq,
1092				   OCFS2_LA_ENABLE_INTERVAL);
1093		goto out_unlock;
1094	}
1095
1096	/*
1097	 * Don't increase the size of the local alloc window until we
1098	 * know we might be able to fulfill the request. Otherwise, we
1099	 * risk bouncing around the global bitmap during periods of
1100	 * low space.
1101	 */
1102	if (osb->local_alloc_state != OCFS2_LA_THROTTLED)
1103		osb->local_alloc_bits = osb->local_alloc_default_bits;
1104
1105out_unlock:
1106	state = osb->local_alloc_state;
1107	spin_unlock(&osb->osb_lock);
1108
1109	return state;
1110}
1111
1112static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb,
1113						struct ocfs2_alloc_context **ac,
1114						struct inode **bitmap_inode,
1115						struct buffer_head **bitmap_bh)
1116{
1117	int status;
1118
1119	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1120	if (!(*ac)) {
1121		status = -ENOMEM;
1122		mlog_errno(status);
1123		goto bail;
1124	}
1125
1126retry_enospc:
1127	(*ac)->ac_bits_wanted = osb->local_alloc_bits;
1128	status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
1129	if (status == -ENOSPC) {
1130		if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_ENOSPC) ==
1131		    OCFS2_LA_DISABLED)
1132			goto bail;
1133
1134		ocfs2_free_ac_resource(*ac);
1135		memset(*ac, 0, sizeof(struct ocfs2_alloc_context));
1136		goto retry_enospc;
1137	}
1138	if (status < 0) {
1139		mlog_errno(status);
1140		goto bail;
1141	}
1142
1143	*bitmap_inode = (*ac)->ac_inode;
1144	igrab(*bitmap_inode);
1145	*bitmap_bh = (*ac)->ac_bh;
1146	get_bh(*bitmap_bh);
1147	status = 0;
1148bail:
1149	if ((status < 0) && *ac) {
1150		ocfs2_free_alloc_context(*ac);
1151		*ac = NULL;
1152	}
1153
1154	if (status)
1155		mlog_errno(status);
1156	return status;
1157}
1158
1159/*
1160 * pass it the bitmap lock in lock_bh if you have it.
1161 */
1162static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb,
1163					handle_t *handle,
1164					struct ocfs2_alloc_context *ac)
1165{
1166	int status = 0;
1167	u32 cluster_off, cluster_count;
1168	struct ocfs2_dinode *alloc = NULL;
1169	struct ocfs2_local_alloc *la;
1170
1171	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
1172	la = OCFS2_LOCAL_ALLOC(alloc);
1173
1174	trace_ocfs2_local_alloc_new_window(
1175		le32_to_cpu(alloc->id1.bitmap1.i_total),
1176		osb->local_alloc_bits);
1177
1178	/* Instruct the allocation code to try the most recently used
1179	 * cluster group. We'll re-record the group used this pass
1180	 * below. */
1181	ac->ac_last_group = osb->la_last_gd;
1182
1183	/* we used the generic suballoc reserve function, but we set
1184	 * everything up nicely, so there's no reason why we can't use
1185	 * the more specific cluster api to claim bits. */
1186	status = ocfs2_claim_clusters(handle, ac, osb->local_alloc_bits,
1187				      &cluster_off, &cluster_count);
1188	if (status == -ENOSPC) {
1189retry_enospc:
1190		/*
1191		 * Note: We could also try syncing the journal here to
1192		 * allow use of any free bits which the current
1193		 * transaction can't give us access to. --Mark
1194		 */
1195		if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_FRAGMENTED) ==
1196		    OCFS2_LA_DISABLED)
1197			goto bail;
1198
1199		ac->ac_bits_wanted = osb->local_alloc_bits;
1200		status = ocfs2_claim_clusters(handle, ac,
1201					      osb->local_alloc_bits,
1202					      &cluster_off,
1203					      &cluster_count);
1204		if (status == -ENOSPC)
1205			goto retry_enospc;
1206		/*
1207		 * We only shrunk the *minimum* number of in our
1208		 * request - it's entirely possible that the allocator
1209		 * might give us more than we asked for.
1210		 */
1211		if (status == 0) {
1212			spin_lock(&osb->osb_lock);
1213			osb->local_alloc_bits = cluster_count;
1214			spin_unlock(&osb->osb_lock);
1215		}
1216	}
1217	if (status < 0) {
1218		if (status != -ENOSPC)
1219			mlog_errno(status);
1220		goto bail;
1221	}
1222
1223	osb->la_last_gd = ac->ac_last_group;
1224
1225	la->la_bm_off = cpu_to_le32(cluster_off);
1226	alloc->id1.bitmap1.i_total = cpu_to_le32(cluster_count);
1227	/* just in case... In the future when we find space ourselves,
1228	 * we don't have to get all contiguous -- but we'll have to
1229	 * set all previously used bits in bitmap and update
1230	 * la_bits_set before setting the bits in the main bitmap. */
1231	alloc->id1.bitmap1.i_used = 0;
1232	memset(OCFS2_LOCAL_ALLOC(alloc)->la_bitmap, 0,
1233	       le16_to_cpu(la->la_size));
1234
1235	ocfs2_resmap_restart(&osb->osb_la_resmap, cluster_count,
1236			     OCFS2_LOCAL_ALLOC(alloc)->la_bitmap);
1237
1238	trace_ocfs2_local_alloc_new_window_result(
1239		OCFS2_LOCAL_ALLOC(alloc)->la_bm_off,
1240		le32_to_cpu(alloc->id1.bitmap1.i_total));
1241
1242bail:
1243	if (status)
1244		mlog_errno(status);
1245	return status;
1246}
1247
1248/* Note that we do *NOT* lock the local alloc inode here as
1249 * it's been locked already for us. */
1250static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb,
1251					  struct inode *local_alloc_inode)
1252{
1253	int status = 0;
1254	struct buffer_head *main_bm_bh = NULL;
1255	struct inode *main_bm_inode = NULL;
1256	handle_t *handle = NULL;
1257	struct ocfs2_dinode *alloc;
1258	struct ocfs2_dinode *alloc_copy = NULL;
1259	struct ocfs2_alloc_context *ac = NULL;
1260
1261	ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_SLIDE);
1262
1263	/* This will lock the main bitmap for us. */
1264	status = ocfs2_local_alloc_reserve_for_window(osb,
1265						      &ac,
1266						      &main_bm_inode,
1267						      &main_bm_bh);
1268	if (status < 0) {
1269		if (status != -ENOSPC)
1270			mlog_errno(status);
1271		goto bail;
1272	}
1273
1274	handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS);
1275	if (IS_ERR(handle)) {
1276		status = PTR_ERR(handle);
1277		handle = NULL;
1278		mlog_errno(status);
1279		goto bail;
1280	}
1281
1282	alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data;
1283
1284	/* We want to clear the local alloc before doing anything
1285	 * else, so that if we error later during this operation,
1286	 * local alloc shutdown won't try to double free main bitmap
1287	 * bits. Make a copy so the sync function knows which bits to
1288	 * free. */
1289	alloc_copy = kmalloc(osb->local_alloc_bh->b_size, GFP_NOFS);
1290	if (!alloc_copy) {
1291		status = -ENOMEM;
1292		mlog_errno(status);
1293		goto bail;
1294	}
1295	memcpy(alloc_copy, alloc, osb->local_alloc_bh->b_size);
1296
1297	status = ocfs2_journal_access_di(handle,
1298					 INODE_CACHE(local_alloc_inode),
1299					 osb->local_alloc_bh,
1300					 OCFS2_JOURNAL_ACCESS_WRITE);
1301	if (status < 0) {
1302		mlog_errno(status);
1303		goto bail;
1304	}
1305
1306	ocfs2_clear_local_alloc(alloc);
1307	ocfs2_journal_dirty(handle, osb->local_alloc_bh);
1308
1309	status = ocfs2_sync_local_to_main(osb, handle, alloc_copy,
1310					  main_bm_inode, main_bm_bh);
1311	if (status < 0) {
1312		mlog_errno(status);
1313		goto bail;
1314	}
1315
1316	status = ocfs2_local_alloc_new_window(osb, handle, ac);
1317	if (status < 0) {
1318		if (status != -ENOSPC)
1319			mlog_errno(status);
1320		goto bail;
1321	}
1322
1323	atomic_inc(&osb->alloc_stats.moves);
1324
1325bail:
1326	if (handle)
1327		ocfs2_commit_trans(osb, handle);
1328
1329	brelse(main_bm_bh);
1330
1331	if (main_bm_inode)
1332		iput(main_bm_inode);
1333
1334	kfree(alloc_copy);
1335
1336	if (ac)
1337		ocfs2_free_alloc_context(ac);
1338
1339	if (status)
1340		mlog_errno(status);
1341	return status;
1342}
1343