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v3.15
   1/* -*- mode: c; c-basic-offset: 8; -*-
   2 * vim: noexpandtab sw=8 ts=8 sts=0:
   3 *
   4 * suballoc.c
   5 *
   6 * metadata alloc and free
   7 * Inspired by ext3 block groups.
   8 *
   9 * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
  10 *
  11 * This program is free software; you can redistribute it and/or
  12 * modify it under the terms of the GNU General Public
  13 * License as published by the Free Software Foundation; either
  14 * version 2 of the License, or (at your option) any later version.
  15 *
  16 * This program is distributed in the hope that it will be useful,
  17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19 * General Public License for more details.
  20 *
  21 * You should have received a copy of the GNU General Public
  22 * License along with this program; if not, write to the
  23 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24 * Boston, MA 021110-1307, USA.
  25 */
  26
  27#include <linux/fs.h>
  28#include <linux/types.h>
  29#include <linux/slab.h>
  30#include <linux/highmem.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 "uptodate.h"
  46#include "ocfs2_trace.h"
  47
  48#include "buffer_head_io.h"
  49
  50#define NOT_ALLOC_NEW_GROUP		0
  51#define ALLOC_NEW_GROUP			0x1
  52#define ALLOC_GROUPS_FROM_GLOBAL	0x2
  53
  54#define OCFS2_MAX_TO_STEAL		1024
  55
  56struct ocfs2_suballoc_result {
  57	u64		sr_bg_blkno;	/* The bg we allocated from.  Set
  58					   to 0 when a block group is
  59					   contiguous. */
  60	u64		sr_bg_stable_blkno; /*
  61					     * Doesn't change, always
  62					     * set to target block
  63					     * group descriptor
  64					     * block.
  65					     */
  66	u64		sr_blkno;	/* The first allocated block */
  67	unsigned int	sr_bit_offset;	/* The bit in the bg */
  68	unsigned int	sr_bits;	/* How many bits we claimed */
 
 
 
 
  69};
  70
  71static u64 ocfs2_group_from_res(struct ocfs2_suballoc_result *res)
  72{
  73	if (res->sr_blkno == 0)
  74		return 0;
  75
  76	if (res->sr_bg_blkno)
  77		return res->sr_bg_blkno;
  78
  79	return ocfs2_which_suballoc_group(res->sr_blkno, res->sr_bit_offset);
  80}
  81
  82static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg);
  83static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe);
  84static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
  85static int ocfs2_block_group_fill(handle_t *handle,
  86				  struct inode *alloc_inode,
  87				  struct buffer_head *bg_bh,
  88				  u64 group_blkno,
  89				  unsigned int group_clusters,
  90				  u16 my_chain,
  91				  struct ocfs2_chain_list *cl);
  92static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
  93				   struct inode *alloc_inode,
  94				   struct buffer_head *bh,
  95				   u64 max_block,
  96				   u64 *last_alloc_group,
  97				   int flags);
  98
  99static int ocfs2_cluster_group_search(struct inode *inode,
 100				      struct buffer_head *group_bh,
 101				      u32 bits_wanted, u32 min_bits,
 102				      u64 max_block,
 103				      struct ocfs2_suballoc_result *res);
 104static int ocfs2_block_group_search(struct inode *inode,
 105				    struct buffer_head *group_bh,
 106				    u32 bits_wanted, u32 min_bits,
 107				    u64 max_block,
 108				    struct ocfs2_suballoc_result *res);
 109static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
 110				     handle_t *handle,
 111				     u32 bits_wanted,
 112				     u32 min_bits,
 113				     struct ocfs2_suballoc_result *res);
 114static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
 115					 int nr);
 116static int ocfs2_relink_block_group(handle_t *handle,
 117				    struct inode *alloc_inode,
 118				    struct buffer_head *fe_bh,
 119				    struct buffer_head *bg_bh,
 120				    struct buffer_head *prev_bg_bh,
 121				    u16 chain);
 122static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
 123						     u32 wanted);
 124static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
 125						   u64 bg_blkno,
 126						   u16 bg_bit_off);
 127static inline void ocfs2_block_to_cluster_group(struct inode *inode,
 128						u64 data_blkno,
 129						u64 *bg_blkno,
 130						u16 *bg_bit_off);
 131static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 132					     u32 bits_wanted, u64 max_block,
 133					     int flags,
 134					     struct ocfs2_alloc_context **ac);
 135
 136void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
 137{
 138	struct inode *inode = ac->ac_inode;
 139
 140	if (inode) {
 141		if (ac->ac_which != OCFS2_AC_USE_LOCAL)
 142			ocfs2_inode_unlock(inode, 1);
 143
 144		mutex_unlock(&inode->i_mutex);
 145
 146		iput(inode);
 147		ac->ac_inode = NULL;
 148	}
 149	brelse(ac->ac_bh);
 150	ac->ac_bh = NULL;
 151	ac->ac_resv = NULL;
 152	if (ac->ac_find_loc_priv) {
 153		kfree(ac->ac_find_loc_priv);
 154		ac->ac_find_loc_priv = NULL;
 155	}
 156}
 157
 158void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
 159{
 160	ocfs2_free_ac_resource(ac);
 161	kfree(ac);
 162}
 163
 164static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
 165{
 166	return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
 167}
 168
 169#define do_error(fmt, ...)						\
 170	do{								\
 171		if (resize)					\
 172			mlog(ML_ERROR, fmt "\n", ##__VA_ARGS__);	\
 173		else							\
 174			ocfs2_error(sb, fmt, ##__VA_ARGS__);		\
 175	} while (0)
 176
 177static int ocfs2_validate_gd_self(struct super_block *sb,
 178				  struct buffer_head *bh,
 179				  int resize)
 180{
 181	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 182
 183	if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
 184		do_error("Group descriptor #%llu has bad signature %.*s",
 185			 (unsigned long long)bh->b_blocknr, 7,
 186			 gd->bg_signature);
 187		return -EINVAL;
 188	}
 189
 190	if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
 191		do_error("Group descriptor #%llu has an invalid bg_blkno "
 192			 "of %llu",
 193			 (unsigned long long)bh->b_blocknr,
 194			 (unsigned long long)le64_to_cpu(gd->bg_blkno));
 195		return -EINVAL;
 196	}
 197
 198	if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
 199		do_error("Group descriptor #%llu has an invalid "
 200			 "fs_generation of #%u",
 201			 (unsigned long long)bh->b_blocknr,
 202			 le32_to_cpu(gd->bg_generation));
 203		return -EINVAL;
 204	}
 205
 206	if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
 207		do_error("Group descriptor #%llu has bit count %u but "
 208			 "claims that %u are free",
 209			 (unsigned long long)bh->b_blocknr,
 210			 le16_to_cpu(gd->bg_bits),
 211			 le16_to_cpu(gd->bg_free_bits_count));
 212		return -EINVAL;
 213	}
 214
 215	if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
 216		do_error("Group descriptor #%llu has bit count %u but "
 217			 "max bitmap bits of %u",
 218			 (unsigned long long)bh->b_blocknr,
 219			 le16_to_cpu(gd->bg_bits),
 220			 8 * le16_to_cpu(gd->bg_size));
 221		return -EINVAL;
 222	}
 223
 224	return 0;
 225}
 226
 227static int ocfs2_validate_gd_parent(struct super_block *sb,
 228				    struct ocfs2_dinode *di,
 229				    struct buffer_head *bh,
 230				    int resize)
 231{
 232	unsigned int max_bits;
 233	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 234
 235	if (di->i_blkno != gd->bg_parent_dinode) {
 236		do_error("Group descriptor #%llu has bad parent "
 237			 "pointer (%llu, expected %llu)",
 238			 (unsigned long long)bh->b_blocknr,
 239			 (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
 240			 (unsigned long long)le64_to_cpu(di->i_blkno));
 241		return -EINVAL;
 242	}
 243
 244	max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
 245	if (le16_to_cpu(gd->bg_bits) > max_bits) {
 246		do_error("Group descriptor #%llu has bit count of %u",
 247			 (unsigned long long)bh->b_blocknr,
 248			 le16_to_cpu(gd->bg_bits));
 249		return -EINVAL;
 250	}
 251
 252	/* In resize, we may meet the case bg_chain == cl_next_free_rec. */
 253	if ((le16_to_cpu(gd->bg_chain) >
 254	     le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) ||
 255	    ((le16_to_cpu(gd->bg_chain) ==
 256	     le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) && !resize)) {
 257		do_error("Group descriptor #%llu has bad chain %u",
 258			 (unsigned long long)bh->b_blocknr,
 259			 le16_to_cpu(gd->bg_chain));
 260		return -EINVAL;
 261	}
 262
 263	return 0;
 264}
 265
 266#undef do_error
 267
 268/*
 269 * This version only prints errors.  It does not fail the filesystem, and
 270 * exists only for resize.
 271 */
 272int ocfs2_check_group_descriptor(struct super_block *sb,
 273				 struct ocfs2_dinode *di,
 274				 struct buffer_head *bh)
 275{
 276	int rc;
 277	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 278
 279	BUG_ON(!buffer_uptodate(bh));
 280
 281	/*
 282	 * If the ecc fails, we return the error but otherwise
 283	 * leave the filesystem running.  We know any error is
 284	 * local to this block.
 285	 */
 286	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 287	if (rc) {
 288		mlog(ML_ERROR,
 289		     "Checksum failed for group descriptor %llu\n",
 290		     (unsigned long long)bh->b_blocknr);
 291	} else
 292		rc = ocfs2_validate_gd_self(sb, bh, 1);
 293	if (!rc)
 294		rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
 295
 296	return rc;
 297}
 298
 299static int ocfs2_validate_group_descriptor(struct super_block *sb,
 300					   struct buffer_head *bh)
 301{
 302	int rc;
 303	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 304
 305	trace_ocfs2_validate_group_descriptor(
 306					(unsigned long long)bh->b_blocknr);
 307
 308	BUG_ON(!buffer_uptodate(bh));
 309
 310	/*
 311	 * If the ecc fails, we return the error but otherwise
 312	 * leave the filesystem running.  We know any error is
 313	 * local to this block.
 314	 */
 315	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 316	if (rc)
 317		return rc;
 318
 319	/*
 320	 * Errors after here are fatal.
 321	 */
 322
 323	return ocfs2_validate_gd_self(sb, bh, 0);
 324}
 325
 326int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 327				u64 gd_blkno, struct buffer_head **bh)
 328{
 329	int rc;
 330	struct buffer_head *tmp = *bh;
 331
 332	rc = ocfs2_read_block(INODE_CACHE(inode), gd_blkno, &tmp,
 333			      ocfs2_validate_group_descriptor);
 334	if (rc)
 335		goto out;
 336
 337	rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
 338	if (rc) {
 339		brelse(tmp);
 340		goto out;
 341	}
 342
 343	/* If ocfs2_read_block() got us a new bh, pass it up. */
 344	if (!*bh)
 345		*bh = tmp;
 346
 347out:
 348	return rc;
 349}
 350
 351static void ocfs2_bg_discontig_add_extent(struct ocfs2_super *osb,
 352					  struct ocfs2_group_desc *bg,
 353					  struct ocfs2_chain_list *cl,
 354					  u64 p_blkno, unsigned int clusters)
 355{
 356	struct ocfs2_extent_list *el = &bg->bg_list;
 357	struct ocfs2_extent_rec *rec;
 358
 359	BUG_ON(!ocfs2_supports_discontig_bg(osb));
 360	if (!el->l_next_free_rec)
 361		el->l_count = cpu_to_le16(ocfs2_extent_recs_per_gd(osb->sb));
 362	rec = &el->l_recs[le16_to_cpu(el->l_next_free_rec)];
 363	rec->e_blkno = cpu_to_le64(p_blkno);
 364	rec->e_cpos = cpu_to_le32(le16_to_cpu(bg->bg_bits) /
 365				  le16_to_cpu(cl->cl_bpc));
 366	rec->e_leaf_clusters = cpu_to_le16(clusters);
 367	le16_add_cpu(&bg->bg_bits, clusters * le16_to_cpu(cl->cl_bpc));
 368	le16_add_cpu(&bg->bg_free_bits_count,
 369		     clusters * le16_to_cpu(cl->cl_bpc));
 370	le16_add_cpu(&el->l_next_free_rec, 1);
 371}
 372
 373static int ocfs2_block_group_fill(handle_t *handle,
 374				  struct inode *alloc_inode,
 375				  struct buffer_head *bg_bh,
 376				  u64 group_blkno,
 377				  unsigned int group_clusters,
 378				  u16 my_chain,
 379				  struct ocfs2_chain_list *cl)
 380{
 381	int status = 0;
 382	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 383	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 384	struct super_block * sb = alloc_inode->i_sb;
 385
 386	if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
 387		ocfs2_error(alloc_inode->i_sb, "group block (%llu) != "
 388			    "b_blocknr (%llu)",
 389			    (unsigned long long)group_blkno,
 390			    (unsigned long long) bg_bh->b_blocknr);
 391		status = -EIO;
 392		goto bail;
 393	}
 394
 395	status = ocfs2_journal_access_gd(handle,
 396					 INODE_CACHE(alloc_inode),
 397					 bg_bh,
 398					 OCFS2_JOURNAL_ACCESS_CREATE);
 399	if (status < 0) {
 400		mlog_errno(status);
 401		goto bail;
 402	}
 403
 404	memset(bg, 0, sb->s_blocksize);
 405	strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
 406	bg->bg_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
 407	bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb, 1,
 408						osb->s_feature_incompat));
 409	bg->bg_chain = cpu_to_le16(my_chain);
 410	bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
 411	bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
 412	bg->bg_blkno = cpu_to_le64(group_blkno);
 413	if (group_clusters == le16_to_cpu(cl->cl_cpg))
 414		bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
 415	else
 416		ocfs2_bg_discontig_add_extent(osb, bg, cl, group_blkno,
 417					      group_clusters);
 418
 419	/* set the 1st bit in the bitmap to account for the descriptor block */
 420	ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
 421	bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
 422
 423	ocfs2_journal_dirty(handle, bg_bh);
 424
 425	/* There is no need to zero out or otherwise initialize the
 426	 * other blocks in a group - All valid FS metadata in a block
 427	 * group stores the superblock fs_generation value at
 428	 * allocation time. */
 429
 430bail:
 431	if (status)
 432		mlog_errno(status);
 433	return status;
 434}
 435
 436static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
 437{
 438	u16 curr, best;
 439
 440	best = curr = 0;
 441	while (curr < le16_to_cpu(cl->cl_count)) {
 442		if (le32_to_cpu(cl->cl_recs[best].c_total) >
 443		    le32_to_cpu(cl->cl_recs[curr].c_total))
 444			best = curr;
 445		curr++;
 446	}
 447	return best;
 448}
 449
 450static struct buffer_head *
 451ocfs2_block_group_alloc_contig(struct ocfs2_super *osb, handle_t *handle,
 452			       struct inode *alloc_inode,
 453			       struct ocfs2_alloc_context *ac,
 454			       struct ocfs2_chain_list *cl)
 455{
 456	int status;
 457	u32 bit_off, num_bits;
 458	u64 bg_blkno;
 459	struct buffer_head *bg_bh;
 460	unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
 461
 462	status = ocfs2_claim_clusters(handle, ac,
 463				      le16_to_cpu(cl->cl_cpg), &bit_off,
 464				      &num_bits);
 465	if (status < 0) {
 466		if (status != -ENOSPC)
 467			mlog_errno(status);
 468		goto bail;
 469	}
 470
 471	/* setup the group */
 472	bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 473	trace_ocfs2_block_group_alloc_contig(
 474	     (unsigned long long)bg_blkno, alloc_rec);
 475
 476	bg_bh = sb_getblk(osb->sb, bg_blkno);
 477	if (!bg_bh) {
 478		status = -ENOMEM;
 479		mlog_errno(status);
 480		goto bail;
 481	}
 482	ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
 483
 484	status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
 485					bg_blkno, num_bits, alloc_rec, cl);
 486	if (status < 0) {
 487		brelse(bg_bh);
 488		mlog_errno(status);
 489	}
 490
 491bail:
 492	return status ? ERR_PTR(status) : bg_bh;
 493}
 494
 495static int ocfs2_block_group_claim_bits(struct ocfs2_super *osb,
 496					handle_t *handle,
 497					struct ocfs2_alloc_context *ac,
 498					unsigned int min_bits,
 499					u32 *bit_off, u32 *num_bits)
 500{
 501	int status = 0;
 502
 503	while (min_bits) {
 504		status = ocfs2_claim_clusters(handle, ac, min_bits,
 505					      bit_off, num_bits);
 506		if (status != -ENOSPC)
 507			break;
 508
 509		min_bits >>= 1;
 510	}
 511
 512	return status;
 513}
 514
 515static int ocfs2_block_group_grow_discontig(handle_t *handle,
 516					    struct inode *alloc_inode,
 517					    struct buffer_head *bg_bh,
 518					    struct ocfs2_alloc_context *ac,
 519					    struct ocfs2_chain_list *cl,
 520					    unsigned int min_bits)
 521{
 522	int status;
 523	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 524	struct ocfs2_group_desc *bg =
 525		(struct ocfs2_group_desc *)bg_bh->b_data;
 526	unsigned int needed = le16_to_cpu(cl->cl_cpg) -
 527			 le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
 528	u32 p_cpos, clusters;
 529	u64 p_blkno;
 530	struct ocfs2_extent_list *el = &bg->bg_list;
 531
 532	status = ocfs2_journal_access_gd(handle,
 533					 INODE_CACHE(alloc_inode),
 534					 bg_bh,
 535					 OCFS2_JOURNAL_ACCESS_CREATE);
 536	if (status < 0) {
 537		mlog_errno(status);
 538		goto bail;
 539	}
 540
 541	while ((needed > 0) && (le16_to_cpu(el->l_next_free_rec) <
 542				le16_to_cpu(el->l_count))) {
 543		if (min_bits > needed)
 544			min_bits = needed;
 545		status = ocfs2_block_group_claim_bits(osb, handle, ac,
 546						      min_bits, &p_cpos,
 547						      &clusters);
 548		if (status < 0) {
 549			if (status != -ENOSPC)
 550				mlog_errno(status);
 551			goto bail;
 552		}
 553		p_blkno = ocfs2_clusters_to_blocks(osb->sb, p_cpos);
 554		ocfs2_bg_discontig_add_extent(osb, bg, cl, p_blkno,
 555					      clusters);
 556
 557		min_bits = clusters;
 558		needed = le16_to_cpu(cl->cl_cpg) -
 559			 le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
 560	}
 561
 562	if (needed > 0) {
 563		/*
 564		 * We have used up all the extent rec but can't fill up
 565		 * the cpg. So bail out.
 566		 */
 567		status = -ENOSPC;
 568		goto bail;
 569	}
 570
 571	ocfs2_journal_dirty(handle, bg_bh);
 572
 573bail:
 574	return status;
 575}
 576
 577static void ocfs2_bg_alloc_cleanup(handle_t *handle,
 578				   struct ocfs2_alloc_context *cluster_ac,
 579				   struct inode *alloc_inode,
 580				   struct buffer_head *bg_bh)
 581{
 582	int i, ret;
 583	struct ocfs2_group_desc *bg;
 584	struct ocfs2_extent_list *el;
 585	struct ocfs2_extent_rec *rec;
 586
 587	if (!bg_bh)
 588		return;
 589
 590	bg = (struct ocfs2_group_desc *)bg_bh->b_data;
 591	el = &bg->bg_list;
 592	for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
 593		rec = &el->l_recs[i];
 594		ret = ocfs2_free_clusters(handle, cluster_ac->ac_inode,
 595					  cluster_ac->ac_bh,
 596					  le64_to_cpu(rec->e_blkno),
 597					  le16_to_cpu(rec->e_leaf_clusters));
 598		if (ret)
 599			mlog_errno(ret);
 600		/* Try all the clusters to free */
 601	}
 602
 603	ocfs2_remove_from_cache(INODE_CACHE(alloc_inode), bg_bh);
 604	brelse(bg_bh);
 605}
 606
 607static struct buffer_head *
 608ocfs2_block_group_alloc_discontig(handle_t *handle,
 609				  struct inode *alloc_inode,
 610				  struct ocfs2_alloc_context *ac,
 611				  struct ocfs2_chain_list *cl)
 612{
 613	int status;
 614	u32 bit_off, num_bits;
 615	u64 bg_blkno;
 616	unsigned int min_bits = le16_to_cpu(cl->cl_cpg) >> 1;
 617	struct buffer_head *bg_bh = NULL;
 618	unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
 619	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 620
 621	if (!ocfs2_supports_discontig_bg(osb)) {
 622		status = -ENOSPC;
 623		goto bail;
 624	}
 625
 626	status = ocfs2_extend_trans(handle,
 627				    ocfs2_calc_bg_discontig_credits(osb->sb));
 628	if (status) {
 629		mlog_errno(status);
 630		goto bail;
 631	}
 632
 633	/*
 634	 * We're going to be grabbing from multiple cluster groups.
 635	 * We don't have enough credits to relink them all, and the
 636	 * cluster groups will be staying in cache for the duration of
 637	 * this operation.
 638	 */
 639	ac->ac_disable_chain_relink = 1;
 640
 641	/* Claim the first region */
 642	status = ocfs2_block_group_claim_bits(osb, handle, ac, min_bits,
 643					      &bit_off, &num_bits);
 644	if (status < 0) {
 645		if (status != -ENOSPC)
 646			mlog_errno(status);
 647		goto bail;
 648	}
 649	min_bits = num_bits;
 650
 651	/* setup the group */
 652	bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 653	trace_ocfs2_block_group_alloc_discontig(
 654				(unsigned long long)bg_blkno, alloc_rec);
 655
 656	bg_bh = sb_getblk(osb->sb, bg_blkno);
 657	if (!bg_bh) {
 658		status = -ENOMEM;
 659		mlog_errno(status);
 660		goto bail;
 661	}
 662	ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
 663
 664	status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
 665					bg_blkno, num_bits, alloc_rec, cl);
 666	if (status < 0) {
 667		mlog_errno(status);
 668		goto bail;
 669	}
 670
 671	status = ocfs2_block_group_grow_discontig(handle, alloc_inode,
 672						  bg_bh, ac, cl, min_bits);
 673	if (status)
 674		mlog_errno(status);
 675
 676bail:
 677	if (status)
 678		ocfs2_bg_alloc_cleanup(handle, ac, alloc_inode, bg_bh);
 679	return status ? ERR_PTR(status) : bg_bh;
 680}
 681
 682/*
 683 * We expect the block group allocator to already be locked.
 684 */
 685static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
 686				   struct inode *alloc_inode,
 687				   struct buffer_head *bh,
 688				   u64 max_block,
 689				   u64 *last_alloc_group,
 690				   int flags)
 691{
 692	int status, credits;
 693	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
 694	struct ocfs2_chain_list *cl;
 695	struct ocfs2_alloc_context *ac = NULL;
 696	handle_t *handle = NULL;
 697	u16 alloc_rec;
 698	struct buffer_head *bg_bh = NULL;
 699	struct ocfs2_group_desc *bg;
 700
 701	BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
 702
 703	cl = &fe->id2.i_chain;
 704	status = ocfs2_reserve_clusters_with_limit(osb,
 705						   le16_to_cpu(cl->cl_cpg),
 706						   max_block, flags, &ac);
 707	if (status < 0) {
 708		if (status != -ENOSPC)
 709			mlog_errno(status);
 710		goto bail;
 711	}
 712
 713	credits = ocfs2_calc_group_alloc_credits(osb->sb,
 714						 le16_to_cpu(cl->cl_cpg));
 715	handle = ocfs2_start_trans(osb, credits);
 716	if (IS_ERR(handle)) {
 717		status = PTR_ERR(handle);
 718		handle = NULL;
 719		mlog_errno(status);
 720		goto bail;
 721	}
 722
 723	if (last_alloc_group && *last_alloc_group != 0) {
 724		trace_ocfs2_block_group_alloc(
 725				(unsigned long long)*last_alloc_group);
 726		ac->ac_last_group = *last_alloc_group;
 727	}
 728
 729	bg_bh = ocfs2_block_group_alloc_contig(osb, handle, alloc_inode,
 730					       ac, cl);
 731	if (IS_ERR(bg_bh) && (PTR_ERR(bg_bh) == -ENOSPC))
 732		bg_bh = ocfs2_block_group_alloc_discontig(handle,
 733							  alloc_inode,
 734							  ac, cl);
 735	if (IS_ERR(bg_bh)) {
 736		status = PTR_ERR(bg_bh);
 737		bg_bh = NULL;
 738		if (status != -ENOSPC)
 739			mlog_errno(status);
 740		goto bail;
 741	}
 742	bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 743
 744	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
 745					 bh, OCFS2_JOURNAL_ACCESS_WRITE);
 746	if (status < 0) {
 747		mlog_errno(status);
 748		goto bail;
 749	}
 750
 751	alloc_rec = le16_to_cpu(bg->bg_chain);
 752	le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
 753		     le16_to_cpu(bg->bg_free_bits_count));
 754	le32_add_cpu(&cl->cl_recs[alloc_rec].c_total,
 755		     le16_to_cpu(bg->bg_bits));
 756	cl->cl_recs[alloc_rec].c_blkno = bg->bg_blkno;
 757	if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
 758		le16_add_cpu(&cl->cl_next_free_rec, 1);
 759
 760	le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
 761					le16_to_cpu(bg->bg_free_bits_count));
 762	le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
 763	le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
 764
 765	ocfs2_journal_dirty(handle, bh);
 766
 767	spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
 768	OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 769	fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
 770					     le32_to_cpu(fe->i_clusters)));
 771	spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
 772	i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
 773	alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
 774	ocfs2_update_inode_fsync_trans(handle, alloc_inode, 0);
 775
 776	status = 0;
 777
 778	/* save the new last alloc group so that the caller can cache it. */
 779	if (last_alloc_group)
 780		*last_alloc_group = ac->ac_last_group;
 781
 782bail:
 783	if (handle)
 784		ocfs2_commit_trans(osb, handle);
 785
 786	if (ac)
 787		ocfs2_free_alloc_context(ac);
 788
 789	brelse(bg_bh);
 790
 791	if (status)
 792		mlog_errno(status);
 793	return status;
 794}
 795
 796static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
 797				       struct ocfs2_alloc_context *ac,
 798				       int type,
 799				       u32 slot,
 800				       u64 *last_alloc_group,
 801				       int flags)
 802{
 803	int status;
 804	u32 bits_wanted = ac->ac_bits_wanted;
 805	struct inode *alloc_inode;
 806	struct buffer_head *bh = NULL;
 807	struct ocfs2_dinode *fe;
 808	u32 free_bits;
 809
 810	alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
 811	if (!alloc_inode) {
 812		mlog_errno(-EINVAL);
 813		return -EINVAL;
 814	}
 815
 816	mutex_lock(&alloc_inode->i_mutex);
 817
 818	status = ocfs2_inode_lock(alloc_inode, &bh, 1);
 819	if (status < 0) {
 820		mutex_unlock(&alloc_inode->i_mutex);
 821		iput(alloc_inode);
 822
 823		mlog_errno(status);
 824		return status;
 825	}
 826
 827	ac->ac_inode = alloc_inode;
 828	ac->ac_alloc_slot = slot;
 829
 830	fe = (struct ocfs2_dinode *) bh->b_data;
 831
 832	/* The bh was validated by the inode read inside
 833	 * ocfs2_inode_lock().  Any corruption is a code bug. */
 834	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
 835
 836	if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
 837		ocfs2_error(alloc_inode->i_sb, "Invalid chain allocator %llu",
 838			    (unsigned long long)le64_to_cpu(fe->i_blkno));
 839		status = -EIO;
 840		goto bail;
 841	}
 842
 843	free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
 844		le32_to_cpu(fe->id1.bitmap1.i_used);
 845
 846	if (bits_wanted > free_bits) {
 847		/* cluster bitmap never grows */
 848		if (ocfs2_is_cluster_bitmap(alloc_inode)) {
 849			trace_ocfs2_reserve_suballoc_bits_nospc(bits_wanted,
 850								free_bits);
 851			status = -ENOSPC;
 852			goto bail;
 853		}
 854
 855		if (!(flags & ALLOC_NEW_GROUP)) {
 856			trace_ocfs2_reserve_suballoc_bits_no_new_group(
 857						slot, bits_wanted, free_bits);
 858			status = -ENOSPC;
 859			goto bail;
 860		}
 861
 862		status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
 863						 ac->ac_max_block,
 864						 last_alloc_group, flags);
 865		if (status < 0) {
 866			if (status != -ENOSPC)
 867				mlog_errno(status);
 868			goto bail;
 869		}
 870		atomic_inc(&osb->alloc_stats.bg_extends);
 871
 872		/* You should never ask for this much metadata */
 873		BUG_ON(bits_wanted >
 874		       (le32_to_cpu(fe->id1.bitmap1.i_total)
 875			- le32_to_cpu(fe->id1.bitmap1.i_used)));
 876	}
 877
 878	get_bh(bh);
 879	ac->ac_bh = bh;
 880bail:
 881	brelse(bh);
 882
 883	if (status)
 884		mlog_errno(status);
 885	return status;
 886}
 887
 888static void ocfs2_init_inode_steal_slot(struct ocfs2_super *osb)
 889{
 890	spin_lock(&osb->osb_lock);
 891	osb->s_inode_steal_slot = OCFS2_INVALID_SLOT;
 892	spin_unlock(&osb->osb_lock);
 893	atomic_set(&osb->s_num_inodes_stolen, 0);
 894}
 895
 896static void ocfs2_init_meta_steal_slot(struct ocfs2_super *osb)
 897{
 898	spin_lock(&osb->osb_lock);
 899	osb->s_meta_steal_slot = OCFS2_INVALID_SLOT;
 900	spin_unlock(&osb->osb_lock);
 901	atomic_set(&osb->s_num_meta_stolen, 0);
 902}
 903
 904void ocfs2_init_steal_slots(struct ocfs2_super *osb)
 905{
 906	ocfs2_init_inode_steal_slot(osb);
 907	ocfs2_init_meta_steal_slot(osb);
 908}
 909
 910static void __ocfs2_set_steal_slot(struct ocfs2_super *osb, int slot, int type)
 911{
 912	spin_lock(&osb->osb_lock);
 913	if (type == INODE_ALLOC_SYSTEM_INODE)
 914		osb->s_inode_steal_slot = slot;
 915	else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 916		osb->s_meta_steal_slot = slot;
 917	spin_unlock(&osb->osb_lock);
 918}
 919
 920static int __ocfs2_get_steal_slot(struct ocfs2_super *osb, int type)
 921{
 922	int slot = OCFS2_INVALID_SLOT;
 923
 924	spin_lock(&osb->osb_lock);
 925	if (type == INODE_ALLOC_SYSTEM_INODE)
 926		slot = osb->s_inode_steal_slot;
 927	else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 928		slot = osb->s_meta_steal_slot;
 929	spin_unlock(&osb->osb_lock);
 930
 931	return slot;
 932}
 933
 934static int ocfs2_get_inode_steal_slot(struct ocfs2_super *osb)
 935{
 936	return __ocfs2_get_steal_slot(osb, INODE_ALLOC_SYSTEM_INODE);
 937}
 938
 939static int ocfs2_get_meta_steal_slot(struct ocfs2_super *osb)
 940{
 941	return __ocfs2_get_steal_slot(osb, EXTENT_ALLOC_SYSTEM_INODE);
 942}
 943
 944static int ocfs2_steal_resource(struct ocfs2_super *osb,
 945				struct ocfs2_alloc_context *ac,
 946				int type)
 947{
 948	int i, status = -ENOSPC;
 949	int slot = __ocfs2_get_steal_slot(osb, type);
 950
 951	/* Start to steal resource from the first slot after ours. */
 952	if (slot == OCFS2_INVALID_SLOT)
 953		slot = osb->slot_num + 1;
 954
 955	for (i = 0; i < osb->max_slots; i++, slot++) {
 956		if (slot == osb->max_slots)
 957			slot = 0;
 958
 959		if (slot == osb->slot_num)
 960			continue;
 961
 962		status = ocfs2_reserve_suballoc_bits(osb, ac,
 963						     type,
 964						     (u32)slot, NULL,
 965						     NOT_ALLOC_NEW_GROUP);
 966		if (status >= 0) {
 967			__ocfs2_set_steal_slot(osb, slot, type);
 968			break;
 969		}
 970
 971		ocfs2_free_ac_resource(ac);
 972	}
 973
 974	return status;
 975}
 976
 977static int ocfs2_steal_inode(struct ocfs2_super *osb,
 978			     struct ocfs2_alloc_context *ac)
 979{
 980	return ocfs2_steal_resource(osb, ac, INODE_ALLOC_SYSTEM_INODE);
 981}
 982
 983static int ocfs2_steal_meta(struct ocfs2_super *osb,
 984			    struct ocfs2_alloc_context *ac)
 985{
 986	return ocfs2_steal_resource(osb, ac, EXTENT_ALLOC_SYSTEM_INODE);
 987}
 988
 989int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
 990				      int blocks,
 991				      struct ocfs2_alloc_context **ac)
 992{
 993	int status;
 994	int slot = ocfs2_get_meta_steal_slot(osb);
 995
 996	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 997	if (!(*ac)) {
 998		status = -ENOMEM;
 999		mlog_errno(status);
1000		goto bail;
1001	}
1002
1003	(*ac)->ac_bits_wanted = blocks;
1004	(*ac)->ac_which = OCFS2_AC_USE_META;
1005	(*ac)->ac_group_search = ocfs2_block_group_search;
1006
1007	if (slot != OCFS2_INVALID_SLOT &&
1008		atomic_read(&osb->s_num_meta_stolen) < OCFS2_MAX_TO_STEAL)
1009		goto extent_steal;
1010
1011	atomic_set(&osb->s_num_meta_stolen, 0);
1012	status = ocfs2_reserve_suballoc_bits(osb, (*ac),
1013					     EXTENT_ALLOC_SYSTEM_INODE,
1014					     (u32)osb->slot_num, NULL,
1015					     ALLOC_GROUPS_FROM_GLOBAL|ALLOC_NEW_GROUP);
1016
1017
1018	if (status >= 0) {
1019		status = 0;
1020		if (slot != OCFS2_INVALID_SLOT)
1021			ocfs2_init_meta_steal_slot(osb);
1022		goto bail;
1023	} else if (status < 0 && status != -ENOSPC) {
1024		mlog_errno(status);
1025		goto bail;
1026	}
1027
1028	ocfs2_free_ac_resource(*ac);
1029
1030extent_steal:
1031	status = ocfs2_steal_meta(osb, *ac);
1032	atomic_inc(&osb->s_num_meta_stolen);
1033	if (status < 0) {
1034		if (status != -ENOSPC)
1035			mlog_errno(status);
1036		goto bail;
1037	}
1038
1039	status = 0;
1040bail:
1041	if ((status < 0) && *ac) {
1042		ocfs2_free_alloc_context(*ac);
1043		*ac = NULL;
1044	}
1045
1046	if (status)
1047		mlog_errno(status);
1048	return status;
1049}
1050
1051int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
1052			       struct ocfs2_extent_list *root_el,
1053			       struct ocfs2_alloc_context **ac)
1054{
1055	return ocfs2_reserve_new_metadata_blocks(osb,
1056					ocfs2_extend_meta_needed(root_el),
1057					ac);
1058}
1059
1060int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
1061			    struct ocfs2_alloc_context **ac)
1062{
1063	int status;
1064	int slot = ocfs2_get_inode_steal_slot(osb);
1065	u64 alloc_group;
1066
1067	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1068	if (!(*ac)) {
1069		status = -ENOMEM;
1070		mlog_errno(status);
1071		goto bail;
1072	}
1073
1074	(*ac)->ac_bits_wanted = 1;
1075	(*ac)->ac_which = OCFS2_AC_USE_INODE;
1076
1077	(*ac)->ac_group_search = ocfs2_block_group_search;
1078
1079	/*
1080	 * stat(2) can't handle i_ino > 32bits, so we tell the
1081	 * lower levels not to allocate us a block group past that
1082	 * limit.  The 'inode64' mount option avoids this behavior.
1083	 */
1084	if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
1085		(*ac)->ac_max_block = (u32)~0U;
1086
1087	/*
1088	 * slot is set when we successfully steal inode from other nodes.
1089	 * It is reset in 3 places:
1090	 * 1. when we flush the truncate log
1091	 * 2. when we complete local alloc recovery.
1092	 * 3. when we successfully allocate from our own slot.
1093	 * After it is set, we will go on stealing inodes until we find the
1094	 * need to check our slots to see whether there is some space for us.
1095	 */
1096	if (slot != OCFS2_INVALID_SLOT &&
1097	    atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_TO_STEAL)
1098		goto inode_steal;
1099
1100	atomic_set(&osb->s_num_inodes_stolen, 0);
1101	alloc_group = osb->osb_inode_alloc_group;
1102	status = ocfs2_reserve_suballoc_bits(osb, *ac,
1103					     INODE_ALLOC_SYSTEM_INODE,
1104					     (u32)osb->slot_num,
1105					     &alloc_group,
1106					     ALLOC_NEW_GROUP |
1107					     ALLOC_GROUPS_FROM_GLOBAL);
1108	if (status >= 0) {
1109		status = 0;
1110
1111		spin_lock(&osb->osb_lock);
1112		osb->osb_inode_alloc_group = alloc_group;
1113		spin_unlock(&osb->osb_lock);
1114		trace_ocfs2_reserve_new_inode_new_group(
1115			(unsigned long long)alloc_group);
1116
1117		/*
1118		 * Some inodes must be freed by us, so try to allocate
1119		 * from our own next time.
1120		 */
1121		if (slot != OCFS2_INVALID_SLOT)
1122			ocfs2_init_inode_steal_slot(osb);
1123		goto bail;
1124	} else if (status < 0 && status != -ENOSPC) {
1125		mlog_errno(status);
1126		goto bail;
1127	}
1128
1129	ocfs2_free_ac_resource(*ac);
1130
1131inode_steal:
1132	status = ocfs2_steal_inode(osb, *ac);
1133	atomic_inc(&osb->s_num_inodes_stolen);
1134	if (status < 0) {
1135		if (status != -ENOSPC)
1136			mlog_errno(status);
1137		goto bail;
1138	}
1139
1140	status = 0;
1141bail:
1142	if ((status < 0) && *ac) {
1143		ocfs2_free_alloc_context(*ac);
1144		*ac = NULL;
1145	}
1146
1147	if (status)
1148		mlog_errno(status);
1149	return status;
1150}
1151
1152/* local alloc code has to do the same thing, so rather than do this
1153 * twice.. */
1154int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
1155				      struct ocfs2_alloc_context *ac)
1156{
1157	int status;
1158
1159	ac->ac_which = OCFS2_AC_USE_MAIN;
1160	ac->ac_group_search = ocfs2_cluster_group_search;
1161
1162	status = ocfs2_reserve_suballoc_bits(osb, ac,
1163					     GLOBAL_BITMAP_SYSTEM_INODE,
1164					     OCFS2_INVALID_SLOT, NULL,
1165					     ALLOC_NEW_GROUP);
1166	if (status < 0 && status != -ENOSPC) {
1167		mlog_errno(status);
1168		goto bail;
1169	}
1170
1171bail:
1172	return status;
1173}
1174
1175/* Callers don't need to care which bitmap (local alloc or main) to
1176 * use so we figure it out for them, but unfortunately this clutters
1177 * things a bit. */
1178static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
1179					     u32 bits_wanted, u64 max_block,
1180					     int flags,
1181					     struct ocfs2_alloc_context **ac)
1182{
1183	int status;
 
1184
1185	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1186	if (!(*ac)) {
1187		status = -ENOMEM;
1188		mlog_errno(status);
1189		goto bail;
1190	}
1191
1192	(*ac)->ac_bits_wanted = bits_wanted;
1193	(*ac)->ac_max_block = max_block;
1194
1195	status = -ENOSPC;
1196	if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
1197	    ocfs2_alloc_should_use_local(osb, bits_wanted)) {
1198		status = ocfs2_reserve_local_alloc_bits(osb,
1199							bits_wanted,
1200							*ac);
1201		if ((status < 0) && (status != -ENOSPC)) {
1202			mlog_errno(status);
1203			goto bail;
1204		}
1205	}
1206
1207	if (status == -ENOSPC) {
 
1208		status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1209		if (status < 0) {
1210			if (status != -ENOSPC)
1211				mlog_errno(status);
1212			goto bail;
1213		}
1214	}
1215
1216	status = 0;
1217bail:
1218	if ((status < 0) && *ac) {
1219		ocfs2_free_alloc_context(*ac);
1220		*ac = NULL;
1221	}
1222
1223	if (status)
1224		mlog_errno(status);
1225	return status;
1226}
1227
1228int ocfs2_reserve_clusters(struct ocfs2_super *osb,
1229			   u32 bits_wanted,
1230			   struct ocfs2_alloc_context **ac)
1231{
1232	return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
1233						 ALLOC_NEW_GROUP, ac);
1234}
1235
1236/*
1237 * More or less lifted from ext3. I'll leave their description below:
1238 *
1239 * "For ext3 allocations, we must not reuse any blocks which are
1240 * allocated in the bitmap buffer's "last committed data" copy.  This
1241 * prevents deletes from freeing up the page for reuse until we have
1242 * committed the delete transaction.
1243 *
1244 * If we didn't do this, then deleting something and reallocating it as
1245 * data would allow the old block to be overwritten before the
1246 * transaction committed (because we force data to disk before commit).
1247 * This would lead to corruption if we crashed between overwriting the
1248 * data and committing the delete.
1249 *
1250 * @@@ We may want to make this allocation behaviour conditional on
1251 * data-writes at some point, and disable it for metadata allocations or
1252 * sync-data inodes."
1253 *
1254 * Note: OCFS2 already does this differently for metadata vs data
1255 * allocations, as those bitmaps are separate and undo access is never
1256 * called on a metadata group descriptor.
1257 */
1258static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
1259					 int nr)
1260{
1261	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 
1262	int ret;
1263
1264	if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
1265		return 0;
1266
1267	if (!buffer_jbd(bg_bh))
 
1268		return 1;
1269
1270	jbd_lock_bh_state(bg_bh);
1271	bg = (struct ocfs2_group_desc *) bh2jh(bg_bh)->b_committed_data;
1272	if (bg)
1273		ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
1274	else
1275		ret = 1;
1276	jbd_unlock_bh_state(bg_bh);
 
1277
1278	return ret;
1279}
1280
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1281static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
1282					     struct buffer_head *bg_bh,
1283					     unsigned int bits_wanted,
1284					     unsigned int total_bits,
1285					     struct ocfs2_suballoc_result *res)
1286{
1287	void *bitmap;
1288	u16 best_offset, best_size;
 
1289	int offset, start, found, status = 0;
1290	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1291
1292	/* Callers got this descriptor from
1293	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1294	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1295
1296	found = start = best_offset = best_size = 0;
1297	bitmap = bg->bg_bitmap;
1298
1299	while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
1300		if (offset == total_bits)
1301			break;
1302
1303		if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
1304			/* We found a zero, but we can't use it as it
1305			 * hasn't been put to disk yet! */
1306			found = 0;
1307			start = offset + 1;
1308		} else if (offset == start) {
1309			/* we found a zero */
1310			found++;
1311			/* move start to the next bit to test */
1312			start++;
1313		} else {
1314			/* got a zero after some ones */
1315			found = 1;
1316			start = offset + 1;
 
1317		}
1318		if (found > best_size) {
1319			best_size = found;
1320			best_offset = start - found;
1321		}
1322		/* we got everything we needed */
1323		if (found == bits_wanted) {
1324			/* mlog(0, "Found it all!\n"); */
1325			break;
1326		}
1327	}
1328
 
 
1329	if (best_size) {
1330		res->sr_bit_offset = best_offset;
1331		res->sr_bits = best_size;
1332	} else {
1333		status = -ENOSPC;
1334		/* No error log here -- see the comment above
1335		 * ocfs2_test_bg_bit_allocatable */
1336	}
1337
1338	return status;
1339}
1340
1341int ocfs2_block_group_set_bits(handle_t *handle,
1342					     struct inode *alloc_inode,
1343					     struct ocfs2_group_desc *bg,
1344					     struct buffer_head *group_bh,
1345					     unsigned int bit_off,
1346					     unsigned int num_bits)
 
 
1347{
1348	int status;
1349	void *bitmap = bg->bg_bitmap;
1350	int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
 
 
 
1351
1352	/* All callers get the descriptor via
1353	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1354	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1355	BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
1356
1357	trace_ocfs2_block_group_set_bits(bit_off, num_bits);
1358
1359	if (ocfs2_is_cluster_bitmap(alloc_inode))
1360		journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1361
1362	status = ocfs2_journal_access_gd(handle,
1363					 INODE_CACHE(alloc_inode),
1364					 group_bh,
1365					 journal_type);
1366	if (status < 0) {
1367		mlog_errno(status);
1368		goto bail;
1369	}
1370
1371	le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
1372	if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
1373		ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit"
1374			    " count %u but claims %u are freed. num_bits %d",
1375			    (unsigned long long)le64_to_cpu(bg->bg_blkno),
1376			    le16_to_cpu(bg->bg_bits),
1377			    le16_to_cpu(bg->bg_free_bits_count), num_bits);
1378		return -EROFS;
1379	}
1380	while(num_bits--)
1381		ocfs2_set_bit(bit_off++, bitmap);
1382
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1383	ocfs2_journal_dirty(handle, group_bh);
1384
1385bail:
1386	return status;
1387}
1388
1389/* find the one with the most empty bits */
1390static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
1391{
1392	u16 curr, best;
1393
1394	BUG_ON(!cl->cl_next_free_rec);
1395
1396	best = curr = 0;
1397	while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
1398		if (le32_to_cpu(cl->cl_recs[curr].c_free) >
1399		    le32_to_cpu(cl->cl_recs[best].c_free))
1400			best = curr;
1401		curr++;
1402	}
1403
1404	BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
1405	return best;
1406}
1407
1408static int ocfs2_relink_block_group(handle_t *handle,
1409				    struct inode *alloc_inode,
1410				    struct buffer_head *fe_bh,
1411				    struct buffer_head *bg_bh,
1412				    struct buffer_head *prev_bg_bh,
1413				    u16 chain)
1414{
1415	int status;
1416	/* there is a really tiny chance the journal calls could fail,
1417	 * but we wouldn't want inconsistent blocks in *any* case. */
1418	u64 bg_ptr, prev_bg_ptr;
1419	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
1420	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1421	struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
1422
1423	/* The caller got these descriptors from
1424	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1425	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1426	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
1427
1428	trace_ocfs2_relink_block_group(
1429		(unsigned long long)le64_to_cpu(fe->i_blkno), chain,
1430		(unsigned long long)le64_to_cpu(bg->bg_blkno),
1431		(unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1432
1433	bg_ptr = le64_to_cpu(bg->bg_next_group);
1434	prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1435
1436	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1437					 prev_bg_bh,
1438					 OCFS2_JOURNAL_ACCESS_WRITE);
1439	if (status < 0)
1440		goto out;
1441
1442	prev_bg->bg_next_group = bg->bg_next_group;
1443	ocfs2_journal_dirty(handle, prev_bg_bh);
1444
1445	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1446					 bg_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1447	if (status < 0)
1448		goto out_rollback_prev_bg;
1449
1450	bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1451	ocfs2_journal_dirty(handle, bg_bh);
1452
1453	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
1454					 fe_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1455	if (status < 0)
1456		goto out_rollback_bg;
1457
1458	fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1459	ocfs2_journal_dirty(handle, fe_bh);
1460
1461out:
1462	if (status < 0)
1463		mlog_errno(status);
1464	return status;
1465
1466out_rollback_bg:
1467	bg->bg_next_group = cpu_to_le64(bg_ptr);
1468out_rollback_prev_bg:
1469	prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1470	goto out;
1471}
1472
1473static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1474						     u32 wanted)
1475{
1476	return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1477}
1478
1479/* return 0 on success, -ENOSPC to keep searching and any other < 0
1480 * value on error. */
1481static int ocfs2_cluster_group_search(struct inode *inode,
1482				      struct buffer_head *group_bh,
1483				      u32 bits_wanted, u32 min_bits,
1484				      u64 max_block,
1485				      struct ocfs2_suballoc_result *res)
1486{
1487	int search = -ENOSPC;
1488	int ret;
1489	u64 blkoff;
1490	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1491	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1492	unsigned int max_bits, gd_cluster_off;
1493
1494	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1495
1496	if (gd->bg_free_bits_count) {
 
 
 
 
 
1497		max_bits = le16_to_cpu(gd->bg_bits);
1498
1499		/* Tail groups in cluster bitmaps which aren't cpg
1500		 * aligned are prone to partial extension by a failed
1501		 * fs resize. If the file system resize never got to
1502		 * update the dinode cluster count, then we don't want
1503		 * to trust any clusters past it, regardless of what
1504		 * the group descriptor says. */
1505		gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1506							  le64_to_cpu(gd->bg_blkno));
1507		if ((gd_cluster_off + max_bits) >
1508		    OCFS2_I(inode)->ip_clusters) {
1509			max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1510			trace_ocfs2_cluster_group_search_wrong_max_bits(
1511				(unsigned long long)le64_to_cpu(gd->bg_blkno),
1512				le16_to_cpu(gd->bg_bits),
1513				OCFS2_I(inode)->ip_clusters, max_bits);
1514		}
1515
1516		ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1517							group_bh, bits_wanted,
1518							max_bits, res);
1519		if (ret)
1520			return ret;
1521
1522		if (max_block) {
1523			blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1524							  gd_cluster_off +
1525							  res->sr_bit_offset +
1526							  res->sr_bits);
1527			trace_ocfs2_cluster_group_search_max_block(
1528				(unsigned long long)blkoff,
1529				(unsigned long long)max_block);
1530			if (blkoff > max_block)
1531				return -ENOSPC;
1532		}
1533
1534		/* ocfs2_block_group_find_clear_bits() might
1535		 * return success, but we still want to return
1536		 * -ENOSPC unless it found the minimum number
1537		 * of bits. */
1538		if (min_bits <= res->sr_bits)
1539			search = 0; /* success */
1540		else if (res->sr_bits) {
1541			/*
1542			 * Don't show bits which we'll be returning
1543			 * for allocation to the local alloc bitmap.
1544			 */
1545			ocfs2_local_alloc_seen_free_bits(osb, res->sr_bits);
1546		}
1547	}
1548
1549	return search;
1550}
1551
1552static int ocfs2_block_group_search(struct inode *inode,
1553				    struct buffer_head *group_bh,
1554				    u32 bits_wanted, u32 min_bits,
1555				    u64 max_block,
1556				    struct ocfs2_suballoc_result *res)
1557{
1558	int ret = -ENOSPC;
1559	u64 blkoff;
1560	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1561
1562	BUG_ON(min_bits != 1);
1563	BUG_ON(ocfs2_is_cluster_bitmap(inode));
1564
1565	if (bg->bg_free_bits_count) {
1566		ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1567							group_bh, bits_wanted,
1568							le16_to_cpu(bg->bg_bits),
1569							res);
1570		if (!ret && max_block) {
1571			blkoff = le64_to_cpu(bg->bg_blkno) +
1572				res->sr_bit_offset + res->sr_bits;
1573			trace_ocfs2_block_group_search_max_block(
1574				(unsigned long long)blkoff,
1575				(unsigned long long)max_block);
1576			if (blkoff > max_block)
1577				ret = -ENOSPC;
1578		}
1579	}
1580
1581	return ret;
1582}
1583
1584int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1585				       handle_t *handle,
1586				       struct buffer_head *di_bh,
1587				       u32 num_bits,
1588				       u16 chain)
1589{
1590	int ret;
1591	u32 tmp_used;
1592	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1593	struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1594
1595	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
1596				      OCFS2_JOURNAL_ACCESS_WRITE);
1597	if (ret < 0) {
1598		mlog_errno(ret);
1599		goto out;
1600	}
1601
1602	tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1603	di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1604	le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1605	ocfs2_journal_dirty(handle, di_bh);
1606
1607out:
1608	return ret;
1609}
1610
1611void ocfs2_rollback_alloc_dinode_counts(struct inode *inode,
1612				       struct buffer_head *di_bh,
1613				       u32 num_bits,
1614				       u16 chain)
1615{
1616	u32 tmp_used;
1617	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1618	struct ocfs2_chain_list *cl;
1619
1620	cl = (struct ocfs2_chain_list *)&di->id2.i_chain;
1621	tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1622	di->id1.bitmap1.i_used = cpu_to_le32(tmp_used - num_bits);
1623	le32_add_cpu(&cl->cl_recs[chain].c_free, num_bits);
1624}
1625
1626static int ocfs2_bg_discontig_fix_by_rec(struct ocfs2_suballoc_result *res,
1627					 struct ocfs2_extent_rec *rec,
1628					 struct ocfs2_chain_list *cl)
1629{
1630	unsigned int bpc = le16_to_cpu(cl->cl_bpc);
1631	unsigned int bitoff = le32_to_cpu(rec->e_cpos) * bpc;
1632	unsigned int bitcount = le16_to_cpu(rec->e_leaf_clusters) * bpc;
1633
1634	if (res->sr_bit_offset < bitoff)
1635		return 0;
1636	if (res->sr_bit_offset >= (bitoff + bitcount))
1637		return 0;
1638	res->sr_blkno = le64_to_cpu(rec->e_blkno) +
1639		(res->sr_bit_offset - bitoff);
1640	if ((res->sr_bit_offset + res->sr_bits) > (bitoff + bitcount))
1641		res->sr_bits = (bitoff + bitcount) - res->sr_bit_offset;
1642	return 1;
1643}
1644
1645static void ocfs2_bg_discontig_fix_result(struct ocfs2_alloc_context *ac,
1646					  struct ocfs2_group_desc *bg,
1647					  struct ocfs2_suballoc_result *res)
1648{
1649	int i;
1650	u64 bg_blkno = res->sr_bg_blkno;  /* Save off */
1651	struct ocfs2_extent_rec *rec;
1652	struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1653	struct ocfs2_chain_list *cl = &di->id2.i_chain;
1654
1655	if (ocfs2_is_cluster_bitmap(ac->ac_inode)) {
1656		res->sr_blkno = 0;
1657		return;
1658	}
1659
1660	res->sr_blkno = res->sr_bg_blkno + res->sr_bit_offset;
1661	res->sr_bg_blkno = 0;  /* Clear it for contig block groups */
1662	if (!ocfs2_supports_discontig_bg(OCFS2_SB(ac->ac_inode->i_sb)) ||
1663	    !bg->bg_list.l_next_free_rec)
1664		return;
1665
1666	for (i = 0; i < le16_to_cpu(bg->bg_list.l_next_free_rec); i++) {
1667		rec = &bg->bg_list.l_recs[i];
1668		if (ocfs2_bg_discontig_fix_by_rec(res, rec, cl)) {
1669			res->sr_bg_blkno = bg_blkno;  /* Restore */
1670			break;
1671		}
1672	}
1673}
1674
1675static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1676				  handle_t *handle,
1677				  u32 bits_wanted,
1678				  u32 min_bits,
1679				  struct ocfs2_suballoc_result *res,
1680				  u16 *bits_left)
1681{
1682	int ret;
1683	struct buffer_head *group_bh = NULL;
1684	struct ocfs2_group_desc *gd;
1685	struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1686	struct inode *alloc_inode = ac->ac_inode;
1687
1688	ret = ocfs2_read_group_descriptor(alloc_inode, di,
1689					  res->sr_bg_blkno, &group_bh);
1690	if (ret < 0) {
1691		mlog_errno(ret);
1692		return ret;
1693	}
1694
1695	gd = (struct ocfs2_group_desc *) group_bh->b_data;
1696	ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1697				  ac->ac_max_block, res);
1698	if (ret < 0) {
1699		if (ret != -ENOSPC)
1700			mlog_errno(ret);
1701		goto out;
1702	}
1703
1704	if (!ret)
1705		ocfs2_bg_discontig_fix_result(ac, gd, res);
1706
1707	/*
1708	 * sr_bg_blkno might have been changed by
1709	 * ocfs2_bg_discontig_fix_result
1710	 */
1711	res->sr_bg_stable_blkno = group_bh->b_blocknr;
1712
1713	if (ac->ac_find_loc_only)
1714		goto out_loc_only;
1715
1716	ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1717					       res->sr_bits,
1718					       le16_to_cpu(gd->bg_chain));
1719	if (ret < 0) {
1720		mlog_errno(ret);
1721		goto out;
1722	}
1723
1724	ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1725					 res->sr_bit_offset, res->sr_bits);
 
1726	if (ret < 0) {
1727		ocfs2_rollback_alloc_dinode_counts(alloc_inode, ac->ac_bh,
1728					       res->sr_bits,
1729					       le16_to_cpu(gd->bg_chain));
1730		mlog_errno(ret);
1731	}
1732
1733out_loc_only:
1734	*bits_left = le16_to_cpu(gd->bg_free_bits_count);
1735
1736out:
1737	brelse(group_bh);
1738
1739	return ret;
1740}
1741
1742static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1743			      handle_t *handle,
1744			      u32 bits_wanted,
1745			      u32 min_bits,
1746			      struct ocfs2_suballoc_result *res,
1747			      u16 *bits_left)
1748{
1749	int status;
1750	u16 chain;
1751	u64 next_group;
1752	struct inode *alloc_inode = ac->ac_inode;
1753	struct buffer_head *group_bh = NULL;
1754	struct buffer_head *prev_group_bh = NULL;
1755	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1756	struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1757	struct ocfs2_group_desc *bg;
1758
1759	chain = ac->ac_chain;
1760	trace_ocfs2_search_chain_begin(
1761		(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
1762		bits_wanted, chain);
1763
1764	status = ocfs2_read_group_descriptor(alloc_inode, fe,
1765					     le64_to_cpu(cl->cl_recs[chain].c_blkno),
1766					     &group_bh);
1767	if (status < 0) {
1768		mlog_errno(status);
1769		goto bail;
1770	}
1771	bg = (struct ocfs2_group_desc *) group_bh->b_data;
1772
1773	status = -ENOSPC;
1774	/* for now, the chain search is a bit simplistic. We just use
1775	 * the 1st group with any empty bits. */
1776	while ((status = ac->ac_group_search(alloc_inode, group_bh,
1777					     bits_wanted, min_bits,
1778					     ac->ac_max_block,
1779					     res)) == -ENOSPC) {
1780		if (!bg->bg_next_group)
1781			break;
1782
1783		brelse(prev_group_bh);
1784		prev_group_bh = NULL;
1785
1786		next_group = le64_to_cpu(bg->bg_next_group);
1787		prev_group_bh = group_bh;
1788		group_bh = NULL;
1789		status = ocfs2_read_group_descriptor(alloc_inode, fe,
1790						     next_group, &group_bh);
1791		if (status < 0) {
1792			mlog_errno(status);
1793			goto bail;
1794		}
1795		bg = (struct ocfs2_group_desc *) group_bh->b_data;
1796	}
1797	if (status < 0) {
1798		if (status != -ENOSPC)
1799			mlog_errno(status);
1800		goto bail;
1801	}
1802
1803	trace_ocfs2_search_chain_succ(
1804		(unsigned long long)le64_to_cpu(bg->bg_blkno), res->sr_bits);
1805
1806	res->sr_bg_blkno = le64_to_cpu(bg->bg_blkno);
1807
1808	BUG_ON(res->sr_bits == 0);
1809	if (!status)
1810		ocfs2_bg_discontig_fix_result(ac, bg, res);
1811
1812	/*
1813	 * sr_bg_blkno might have been changed by
1814	 * ocfs2_bg_discontig_fix_result
1815	 */
1816	res->sr_bg_stable_blkno = group_bh->b_blocknr;
1817
1818	/*
1819	 * Keep track of previous block descriptor read. When
1820	 * we find a target, if we have read more than X
1821	 * number of descriptors, and the target is reasonably
1822	 * empty, relink him to top of his chain.
1823	 *
1824	 * We've read 0 extra blocks and only send one more to
1825	 * the transaction, yet the next guy to search has a
1826	 * much easier time.
1827	 *
1828	 * Do this *after* figuring out how many bits we're taking out
1829	 * of our target group.
1830	 */
1831	if (!ac->ac_disable_chain_relink &&
1832	    (prev_group_bh) &&
1833	    (ocfs2_block_group_reasonably_empty(bg, res->sr_bits))) {
1834		status = ocfs2_relink_block_group(handle, alloc_inode,
1835						  ac->ac_bh, group_bh,
1836						  prev_group_bh, chain);
1837		if (status < 0) {
1838			mlog_errno(status);
1839			goto bail;
1840		}
1841	}
1842
1843	if (ac->ac_find_loc_only)
1844		goto out_loc_only;
1845
1846	status = ocfs2_alloc_dinode_update_counts(alloc_inode, handle,
1847						  ac->ac_bh, res->sr_bits,
1848						  chain);
1849	if (status) {
1850		mlog_errno(status);
1851		goto bail;
1852	}
1853
1854	status = ocfs2_block_group_set_bits(handle,
1855					    alloc_inode,
1856					    bg,
1857					    group_bh,
1858					    res->sr_bit_offset,
1859					    res->sr_bits);
 
 
1860	if (status < 0) {
1861		ocfs2_rollback_alloc_dinode_counts(alloc_inode,
1862					ac->ac_bh, res->sr_bits, chain);
1863		mlog_errno(status);
1864		goto bail;
1865	}
1866
1867	trace_ocfs2_search_chain_end(
1868			(unsigned long long)le64_to_cpu(fe->i_blkno),
1869			res->sr_bits);
1870
1871out_loc_only:
1872	*bits_left = le16_to_cpu(bg->bg_free_bits_count);
1873bail:
1874	brelse(group_bh);
1875	brelse(prev_group_bh);
1876
1877	if (status)
1878		mlog_errno(status);
1879	return status;
1880}
1881
1882/* will give out up to bits_wanted contiguous bits. */
1883static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
1884				     handle_t *handle,
1885				     u32 bits_wanted,
1886				     u32 min_bits,
1887				     struct ocfs2_suballoc_result *res)
1888{
1889	int status;
1890	u16 victim, i;
1891	u16 bits_left = 0;
1892	u64 hint = ac->ac_last_group;
1893	struct ocfs2_chain_list *cl;
1894	struct ocfs2_dinode *fe;
1895
1896	BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1897	BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1898	BUG_ON(!ac->ac_bh);
1899
1900	fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1901
1902	/* The bh was validated by the inode read during
1903	 * ocfs2_reserve_suballoc_bits().  Any corruption is a code bug. */
1904	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1905
1906	if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1907	    le32_to_cpu(fe->id1.bitmap1.i_total)) {
1908		ocfs2_error(ac->ac_inode->i_sb,
1909			    "Chain allocator dinode %llu has %u used "
1910			    "bits but only %u total.",
1911			    (unsigned long long)le64_to_cpu(fe->i_blkno),
1912			    le32_to_cpu(fe->id1.bitmap1.i_used),
1913			    le32_to_cpu(fe->id1.bitmap1.i_total));
1914		status = -EIO;
1915		goto bail;
1916	}
1917
1918	res->sr_bg_blkno = hint;
1919	if (res->sr_bg_blkno) {
1920		/* Attempt to short-circuit the usual search mechanism
1921		 * by jumping straight to the most recently used
1922		 * allocation group. This helps us maintain some
1923		 * contiguousness across allocations. */
1924		status = ocfs2_search_one_group(ac, handle, bits_wanted,
1925						min_bits, res, &bits_left);
1926		if (!status)
1927			goto set_hint;
1928		if (status < 0 && status != -ENOSPC) {
1929			mlog_errno(status);
1930			goto bail;
1931		}
1932	}
1933
1934	cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1935
1936	victim = ocfs2_find_victim_chain(cl);
1937	ac->ac_chain = victim;
1938
1939	status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1940				    res, &bits_left);
1941	if (!status) {
1942		hint = ocfs2_group_from_res(res);
 
 
 
1943		goto set_hint;
1944	}
1945	if (status < 0 && status != -ENOSPC) {
1946		mlog_errno(status);
1947		goto bail;
1948	}
1949
1950	trace_ocfs2_claim_suballoc_bits(victim);
1951
1952	/* If we didn't pick a good victim, then just default to
1953	 * searching each chain in order. Don't allow chain relinking
1954	 * because we only calculate enough journal credits for one
1955	 * relink per alloc. */
1956	ac->ac_disable_chain_relink = 1;
1957	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1958		if (i == victim)
1959			continue;
1960		if (!cl->cl_recs[i].c_free)
1961			continue;
1962
1963		ac->ac_chain = i;
1964		status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1965					    res, &bits_left);
1966		if (!status) {
1967			hint = ocfs2_group_from_res(res);
1968			break;
1969		}
1970		if (status < 0 && status != -ENOSPC) {
1971			mlog_errno(status);
1972			goto bail;
1973		}
1974	}
1975
1976set_hint:
1977	if (status != -ENOSPC) {
1978		/* If the next search of this group is not likely to
1979		 * yield a suitable extent, then we reset the last
1980		 * group hint so as to not waste a disk read */
1981		if (bits_left < min_bits)
1982			ac->ac_last_group = 0;
1983		else
1984			ac->ac_last_group = hint;
1985	}
1986
1987bail:
1988	if (status)
1989		mlog_errno(status);
1990	return status;
1991}
1992
1993int ocfs2_claim_metadata(handle_t *handle,
1994			 struct ocfs2_alloc_context *ac,
1995			 u32 bits_wanted,
1996			 u64 *suballoc_loc,
1997			 u16 *suballoc_bit_start,
1998			 unsigned int *num_bits,
1999			 u64 *blkno_start)
2000{
2001	int status;
2002	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2003
2004	BUG_ON(!ac);
2005	BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
2006	BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
2007
2008	status = ocfs2_claim_suballoc_bits(ac,
2009					   handle,
2010					   bits_wanted,
2011					   1,
2012					   &res);
2013	if (status < 0) {
2014		mlog_errno(status);
2015		goto bail;
2016	}
2017	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2018
2019	*suballoc_loc = res.sr_bg_blkno;
2020	*suballoc_bit_start = res.sr_bit_offset;
2021	*blkno_start = res.sr_blkno;
2022	ac->ac_bits_given += res.sr_bits;
2023	*num_bits = res.sr_bits;
2024	status = 0;
2025bail:
2026	if (status)
2027		mlog_errno(status);
2028	return status;
2029}
2030
2031static void ocfs2_init_inode_ac_group(struct inode *dir,
2032				      struct buffer_head *parent_di_bh,
2033				      struct ocfs2_alloc_context *ac)
2034{
2035	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_di_bh->b_data;
2036	/*
2037	 * Try to allocate inodes from some specific group.
2038	 *
2039	 * If the parent dir has recorded the last group used in allocation,
2040	 * cool, use it. Otherwise if we try to allocate new inode from the
2041	 * same slot the parent dir belongs to, use the same chunk.
2042	 *
2043	 * We are very careful here to avoid the mistake of setting
2044	 * ac_last_group to a group descriptor from a different (unlocked) slot.
2045	 */
2046	if (OCFS2_I(dir)->ip_last_used_group &&
2047	    OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
2048		ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
2049	else if (le16_to_cpu(di->i_suballoc_slot) == ac->ac_alloc_slot) {
2050		if (di->i_suballoc_loc)
2051			ac->ac_last_group = le64_to_cpu(di->i_suballoc_loc);
2052		else
2053			ac->ac_last_group = ocfs2_which_suballoc_group(
2054					le64_to_cpu(di->i_blkno),
2055					le16_to_cpu(di->i_suballoc_bit));
2056	}
2057}
2058
2059static inline void ocfs2_save_inode_ac_group(struct inode *dir,
2060					     struct ocfs2_alloc_context *ac)
2061{
2062	OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
2063	OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
2064}
2065
2066int ocfs2_find_new_inode_loc(struct inode *dir,
2067			     struct buffer_head *parent_fe_bh,
2068			     struct ocfs2_alloc_context *ac,
2069			     u64 *fe_blkno)
2070{
2071	int ret;
2072	handle_t *handle = NULL;
2073	struct ocfs2_suballoc_result *res;
2074
2075	BUG_ON(!ac);
2076	BUG_ON(ac->ac_bits_given != 0);
2077	BUG_ON(ac->ac_bits_wanted != 1);
2078	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2079
2080	res = kzalloc(sizeof(*res), GFP_NOFS);
2081	if (res == NULL) {
2082		ret = -ENOMEM;
2083		mlog_errno(ret);
2084		goto out;
2085	}
2086
2087	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2088
2089	/*
2090	 * The handle started here is for chain relink. Alternatively,
2091	 * we could just disable relink for these calls.
2092	 */
2093	handle = ocfs2_start_trans(OCFS2_SB(dir->i_sb), OCFS2_SUBALLOC_ALLOC);
2094	if (IS_ERR(handle)) {
2095		ret = PTR_ERR(handle);
2096		handle = NULL;
2097		mlog_errno(ret);
2098		goto out;
2099	}
2100
2101	/*
2102	 * This will instruct ocfs2_claim_suballoc_bits and
2103	 * ocfs2_search_one_group to search but save actual allocation
2104	 * for later.
2105	 */
2106	ac->ac_find_loc_only = 1;
2107
2108	ret = ocfs2_claim_suballoc_bits(ac, handle, 1, 1, res);
2109	if (ret < 0) {
2110		mlog_errno(ret);
2111		goto out;
2112	}
2113
2114	ac->ac_find_loc_priv = res;
2115	*fe_blkno = res->sr_blkno;
2116	ocfs2_update_inode_fsync_trans(handle, dir, 0);
2117out:
2118	if (handle)
2119		ocfs2_commit_trans(OCFS2_SB(dir->i_sb), handle);
2120
2121	if (ret)
2122		kfree(res);
2123
2124	return ret;
2125}
2126
2127int ocfs2_claim_new_inode_at_loc(handle_t *handle,
2128				 struct inode *dir,
2129				 struct ocfs2_alloc_context *ac,
2130				 u64 *suballoc_loc,
2131				 u16 *suballoc_bit,
2132				 u64 di_blkno)
2133{
2134	int ret;
2135	u16 chain;
2136	struct ocfs2_suballoc_result *res = ac->ac_find_loc_priv;
2137	struct buffer_head *bg_bh = NULL;
2138	struct ocfs2_group_desc *bg;
2139	struct ocfs2_dinode *di = (struct ocfs2_dinode *) ac->ac_bh->b_data;
2140
2141	/*
2142	 * Since di_blkno is being passed back in, we check for any
2143	 * inconsistencies which may have happened between
2144	 * calls. These are code bugs as di_blkno is not expected to
2145	 * change once returned from ocfs2_find_new_inode_loc()
2146	 */
2147	BUG_ON(res->sr_blkno != di_blkno);
2148
2149	ret = ocfs2_read_group_descriptor(ac->ac_inode, di,
2150					  res->sr_bg_stable_blkno, &bg_bh);
2151	if (ret) {
2152		mlog_errno(ret);
2153		goto out;
2154	}
2155
2156	bg = (struct ocfs2_group_desc *) bg_bh->b_data;
2157	chain = le16_to_cpu(bg->bg_chain);
2158
2159	ret = ocfs2_alloc_dinode_update_counts(ac->ac_inode, handle,
2160					       ac->ac_bh, res->sr_bits,
2161					       chain);
2162	if (ret) {
2163		mlog_errno(ret);
2164		goto out;
2165	}
2166
2167	ret = ocfs2_block_group_set_bits(handle,
2168					 ac->ac_inode,
2169					 bg,
2170					 bg_bh,
2171					 res->sr_bit_offset,
2172					 res->sr_bits);
 
 
2173	if (ret < 0) {
2174		ocfs2_rollback_alloc_dinode_counts(ac->ac_inode,
2175					       ac->ac_bh, res->sr_bits, chain);
2176		mlog_errno(ret);
2177		goto out;
2178	}
2179
2180	trace_ocfs2_claim_new_inode_at_loc((unsigned long long)di_blkno,
2181					   res->sr_bits);
2182
2183	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2184
2185	BUG_ON(res->sr_bits != 1);
2186
2187	*suballoc_loc = res->sr_bg_blkno;
2188	*suballoc_bit = res->sr_bit_offset;
2189	ac->ac_bits_given++;
2190	ocfs2_save_inode_ac_group(dir, ac);
2191
2192out:
2193	brelse(bg_bh);
2194
2195	return ret;
2196}
2197
2198int ocfs2_claim_new_inode(handle_t *handle,
2199			  struct inode *dir,
2200			  struct buffer_head *parent_fe_bh,
2201			  struct ocfs2_alloc_context *ac,
2202			  u64 *suballoc_loc,
2203			  u16 *suballoc_bit,
2204			  u64 *fe_blkno)
2205{
2206	int status;
2207	struct ocfs2_suballoc_result res;
2208
2209	BUG_ON(!ac);
2210	BUG_ON(ac->ac_bits_given != 0);
2211	BUG_ON(ac->ac_bits_wanted != 1);
2212	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2213
2214	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2215
2216	status = ocfs2_claim_suballoc_bits(ac,
2217					   handle,
2218					   1,
2219					   1,
2220					   &res);
2221	if (status < 0) {
2222		mlog_errno(status);
2223		goto bail;
2224	}
2225	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2226
2227	BUG_ON(res.sr_bits != 1);
2228
2229	*suballoc_loc = res.sr_bg_blkno;
2230	*suballoc_bit = res.sr_bit_offset;
2231	*fe_blkno = res.sr_blkno;
2232	ac->ac_bits_given++;
2233	ocfs2_save_inode_ac_group(dir, ac);
2234	status = 0;
2235bail:
2236	if (status)
2237		mlog_errno(status);
2238	return status;
2239}
2240
2241/* translate a group desc. blkno and it's bitmap offset into
2242 * disk cluster offset. */
2243static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
2244						   u64 bg_blkno,
2245						   u16 bg_bit_off)
2246{
2247	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2248	u32 cluster = 0;
2249
2250	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2251
2252	if (bg_blkno != osb->first_cluster_group_blkno)
2253		cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
2254	cluster += (u32) bg_bit_off;
2255	return cluster;
2256}
2257
2258/* given a cluster offset, calculate which block group it belongs to
2259 * and return that block offset. */
2260u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
2261{
2262	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2263	u32 group_no;
2264
2265	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2266
2267	group_no = cluster / osb->bitmap_cpg;
2268	if (!group_no)
2269		return osb->first_cluster_group_blkno;
2270	return ocfs2_clusters_to_blocks(inode->i_sb,
2271					group_no * osb->bitmap_cpg);
2272}
2273
2274/* given the block number of a cluster start, calculate which cluster
2275 * group and descriptor bitmap offset that corresponds to. */
2276static inline void ocfs2_block_to_cluster_group(struct inode *inode,
2277						u64 data_blkno,
2278						u64 *bg_blkno,
2279						u16 *bg_bit_off)
2280{
2281	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2282	u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
2283
2284	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2285
2286	*bg_blkno = ocfs2_which_cluster_group(inode,
2287					      data_cluster);
2288
2289	if (*bg_blkno == osb->first_cluster_group_blkno)
2290		*bg_bit_off = (u16) data_cluster;
2291	else
2292		*bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
2293							     data_blkno - *bg_blkno);
2294}
2295
2296/*
2297 * min_bits - minimum contiguous chunk from this total allocation we
2298 * can handle. set to what we asked for originally for a full
2299 * contig. allocation, set to '1' to indicate we can deal with extents
2300 * of any size.
2301 */
2302int __ocfs2_claim_clusters(handle_t *handle,
2303			   struct ocfs2_alloc_context *ac,
2304			   u32 min_clusters,
2305			   u32 max_clusters,
2306			   u32 *cluster_start,
2307			   u32 *num_clusters)
2308{
2309	int status;
2310	unsigned int bits_wanted = max_clusters;
2311	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2312	struct ocfs2_super *osb = OCFS2_SB(ac->ac_inode->i_sb);
2313
2314	BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
2315
2316	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
2317	       && ac->ac_which != OCFS2_AC_USE_MAIN);
2318
2319	if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
2320		WARN_ON(min_clusters > 1);
2321
2322		status = ocfs2_claim_local_alloc_bits(osb,
2323						      handle,
2324						      ac,
2325						      bits_wanted,
2326						      cluster_start,
2327						      num_clusters);
2328		if (!status)
2329			atomic_inc(&osb->alloc_stats.local_data);
2330	} else {
2331		if (min_clusters > (osb->bitmap_cpg - 1)) {
2332			/* The only paths asking for contiguousness
2333			 * should know about this already. */
2334			mlog(ML_ERROR, "minimum allocation requested %u exceeds "
2335			     "group bitmap size %u!\n", min_clusters,
2336			     osb->bitmap_cpg);
2337			status = -ENOSPC;
2338			goto bail;
2339		}
2340		/* clamp the current request down to a realistic size. */
2341		if (bits_wanted > (osb->bitmap_cpg - 1))
2342			bits_wanted = osb->bitmap_cpg - 1;
2343
2344		status = ocfs2_claim_suballoc_bits(ac,
2345						   handle,
2346						   bits_wanted,
2347						   min_clusters,
2348						   &res);
2349		if (!status) {
2350			BUG_ON(res.sr_blkno); /* cluster alloc can't set */
2351			*cluster_start =
2352				ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
2353								 res.sr_bg_blkno,
2354								 res.sr_bit_offset);
2355			atomic_inc(&osb->alloc_stats.bitmap_data);
2356			*num_clusters = res.sr_bits;
2357		}
2358	}
2359	if (status < 0) {
2360		if (status != -ENOSPC)
2361			mlog_errno(status);
2362		goto bail;
2363	}
2364
2365	ac->ac_bits_given += *num_clusters;
2366
2367bail:
2368	if (status)
2369		mlog_errno(status);
2370	return status;
2371}
2372
2373int ocfs2_claim_clusters(handle_t *handle,
2374			 struct ocfs2_alloc_context *ac,
2375			 u32 min_clusters,
2376			 u32 *cluster_start,
2377			 u32 *num_clusters)
2378{
2379	unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
2380
2381	return __ocfs2_claim_clusters(handle, ac, min_clusters,
2382				      bits_wanted, cluster_start, num_clusters);
2383}
2384
2385static int ocfs2_block_group_clear_bits(handle_t *handle,
2386					struct inode *alloc_inode,
2387					struct ocfs2_group_desc *bg,
2388					struct buffer_head *group_bh,
2389					unsigned int bit_off,
2390					unsigned int num_bits,
 
2391					void (*undo_fn)(unsigned int bit,
2392							unsigned long *bmap))
2393{
2394	int status;
2395	unsigned int tmp;
 
2396	struct ocfs2_group_desc *undo_bg = NULL;
 
2397
2398	/* The caller got this descriptor from
2399	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
2400	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
2401
2402	trace_ocfs2_block_group_clear_bits(bit_off, num_bits);
2403
2404	BUG_ON(undo_fn && !ocfs2_is_cluster_bitmap(alloc_inode));
2405	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
2406					 group_bh,
2407					 undo_fn ?
2408					 OCFS2_JOURNAL_ACCESS_UNDO :
2409					 OCFS2_JOURNAL_ACCESS_WRITE);
2410	if (status < 0) {
2411		mlog_errno(status);
2412		goto bail;
2413	}
2414
 
2415	if (undo_fn) {
2416		jbd_lock_bh_state(group_bh);
2417		undo_bg = (struct ocfs2_group_desc *)
2418					bh2jh(group_bh)->b_committed_data;
2419		BUG_ON(!undo_bg);
2420	}
2421
2422	tmp = num_bits;
2423	while(tmp--) {
2424		ocfs2_clear_bit((bit_off + tmp),
2425				(unsigned long *) bg->bg_bitmap);
2426		if (undo_fn)
2427			undo_fn(bit_off + tmp,
2428				(unsigned long *) undo_bg->bg_bitmap);
2429	}
2430	le16_add_cpu(&bg->bg_free_bits_count, num_bits);
2431	if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
2432		ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit"
2433			    " count %u but claims %u are freed. num_bits %d",
2434			    (unsigned long long)le64_to_cpu(bg->bg_blkno),
2435			    le16_to_cpu(bg->bg_bits),
2436			    le16_to_cpu(bg->bg_free_bits_count), num_bits);
2437		return -EROFS;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2438	}
2439
2440	if (undo_fn)
2441		jbd_unlock_bh_state(group_bh);
2442
2443	ocfs2_journal_dirty(handle, group_bh);
2444bail:
2445	return status;
2446}
2447
2448/*
2449 * expects the suballoc inode to already be locked.
2450 */
2451static int _ocfs2_free_suballoc_bits(handle_t *handle,
2452				     struct inode *alloc_inode,
2453				     struct buffer_head *alloc_bh,
2454				     unsigned int start_bit,
2455				     u64 bg_blkno,
2456				     unsigned int count,
2457				     void (*undo_fn)(unsigned int bit,
2458						     unsigned long *bitmap))
2459{
2460	int status = 0;
2461	u32 tmp_used;
2462	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
2463	struct ocfs2_chain_list *cl = &fe->id2.i_chain;
2464	struct buffer_head *group_bh = NULL;
2465	struct ocfs2_group_desc *group;
 
2466
2467	/* The alloc_bh comes from ocfs2_free_dinode() or
2468	 * ocfs2_free_clusters().  The callers have all locked the
2469	 * allocator and gotten alloc_bh from the lock call.  This
2470	 * validates the dinode buffer.  Any corruption that has happened
2471	 * is a code bug. */
2472	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
2473	BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
2474
2475	trace_ocfs2_free_suballoc_bits(
2476		(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
2477		(unsigned long long)bg_blkno,
2478		start_bit, count);
2479
2480	status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
2481					     &group_bh);
2482	if (status < 0) {
2483		mlog_errno(status);
2484		goto bail;
2485	}
2486	group = (struct ocfs2_group_desc *) group_bh->b_data;
2487
2488	BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
2489
 
 
2490	status = ocfs2_block_group_clear_bits(handle, alloc_inode,
2491					      group, group_bh,
2492					      start_bit, count, undo_fn);
2493	if (status < 0) {
2494		mlog_errno(status);
2495		goto bail;
2496	}
2497
2498	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
2499					 alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
2500	if (status < 0) {
2501		mlog_errno(status);
 
 
 
2502		goto bail;
2503	}
2504
2505	le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2506		     count);
2507	tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2508	fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2509	ocfs2_journal_dirty(handle, alloc_bh);
2510
2511bail:
2512	brelse(group_bh);
2513
2514	if (status)
2515		mlog_errno(status);
2516	return status;
2517}
2518
2519int ocfs2_free_suballoc_bits(handle_t *handle,
2520			     struct inode *alloc_inode,
2521			     struct buffer_head *alloc_bh,
2522			     unsigned int start_bit,
2523			     u64 bg_blkno,
2524			     unsigned int count)
2525{
2526	return _ocfs2_free_suballoc_bits(handle, alloc_inode, alloc_bh,
2527					 start_bit, bg_blkno, count, NULL);
2528}
2529
2530int ocfs2_free_dinode(handle_t *handle,
2531		      struct inode *inode_alloc_inode,
2532		      struct buffer_head *inode_alloc_bh,
2533		      struct ocfs2_dinode *di)
2534{
2535	u64 blk = le64_to_cpu(di->i_blkno);
2536	u16 bit = le16_to_cpu(di->i_suballoc_bit);
2537	u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2538
2539	if (di->i_suballoc_loc)
2540		bg_blkno = le64_to_cpu(di->i_suballoc_loc);
2541	return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2542					inode_alloc_bh, bit, bg_blkno, 1);
2543}
2544
2545static int _ocfs2_free_clusters(handle_t *handle,
2546				struct inode *bitmap_inode,
2547				struct buffer_head *bitmap_bh,
2548				u64 start_blk,
2549				unsigned int num_clusters,
2550				void (*undo_fn)(unsigned int bit,
2551						unsigned long *bitmap))
2552{
2553	int status;
2554	u16 bg_start_bit;
2555	u64 bg_blkno;
2556	struct ocfs2_dinode *fe;
2557
2558	/* You can't ever have a contiguous set of clusters
2559	 * bigger than a block group bitmap so we never have to worry
2560	 * about looping on them.
2561	 * This is expensive. We can safely remove once this stuff has
2562	 * gotten tested really well. */
2563	BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb, ocfs2_blocks_to_clusters(bitmap_inode->i_sb, start_blk)));
 
 
2564
2565	fe = (struct ocfs2_dinode *) bitmap_bh->b_data;
2566
2567	ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2568				     &bg_start_bit);
2569
2570	trace_ocfs2_free_clusters((unsigned long long)bg_blkno,
2571			(unsigned long long)start_blk,
2572			bg_start_bit, num_clusters);
2573
2574	status = _ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2575					   bg_start_bit, bg_blkno,
2576					   num_clusters, undo_fn);
2577	if (status < 0) {
2578		mlog_errno(status);
2579		goto out;
2580	}
2581
2582	ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2583					 num_clusters);
2584
2585out:
2586	if (status)
2587		mlog_errno(status);
2588	return status;
2589}
2590
2591int ocfs2_free_clusters(handle_t *handle,
2592			struct inode *bitmap_inode,
2593			struct buffer_head *bitmap_bh,
2594			u64 start_blk,
2595			unsigned int num_clusters)
2596{
2597	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2598				    start_blk, num_clusters,
2599				    _ocfs2_set_bit);
2600}
2601
2602/*
2603 * Give never-used clusters back to the global bitmap.  We don't need
2604 * to protect these bits in the undo buffer.
2605 */
2606int ocfs2_release_clusters(handle_t *handle,
2607			   struct inode *bitmap_inode,
2608			   struct buffer_head *bitmap_bh,
2609			   u64 start_blk,
2610			   unsigned int num_clusters)
2611{
2612	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2613				    start_blk, num_clusters,
2614				    _ocfs2_clear_bit);
2615}
2616
2617static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg)
2618{
2619	printk("Block Group:\n");
2620	printk("bg_signature:       %s\n", bg->bg_signature);
2621	printk("bg_size:            %u\n", bg->bg_size);
2622	printk("bg_bits:            %u\n", bg->bg_bits);
2623	printk("bg_free_bits_count: %u\n", bg->bg_free_bits_count);
2624	printk("bg_chain:           %u\n", bg->bg_chain);
2625	printk("bg_generation:      %u\n", le32_to_cpu(bg->bg_generation));
2626	printk("bg_next_group:      %llu\n",
2627	       (unsigned long long)bg->bg_next_group);
2628	printk("bg_parent_dinode:   %llu\n",
2629	       (unsigned long long)bg->bg_parent_dinode);
2630	printk("bg_blkno:           %llu\n",
2631	       (unsigned long long)bg->bg_blkno);
2632}
2633
2634static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe)
2635{
2636	int i;
2637
2638	printk("Suballoc Inode %llu:\n", (unsigned long long)fe->i_blkno);
2639	printk("i_signature:                  %s\n", fe->i_signature);
2640	printk("i_size:                       %llu\n",
2641	       (unsigned long long)fe->i_size);
2642	printk("i_clusters:                   %u\n", fe->i_clusters);
2643	printk("i_generation:                 %u\n",
2644	       le32_to_cpu(fe->i_generation));
2645	printk("id1.bitmap1.i_used:           %u\n",
2646	       le32_to_cpu(fe->id1.bitmap1.i_used));
2647	printk("id1.bitmap1.i_total:          %u\n",
2648	       le32_to_cpu(fe->id1.bitmap1.i_total));
2649	printk("id2.i_chain.cl_cpg:           %u\n", fe->id2.i_chain.cl_cpg);
2650	printk("id2.i_chain.cl_bpc:           %u\n", fe->id2.i_chain.cl_bpc);
2651	printk("id2.i_chain.cl_count:         %u\n", fe->id2.i_chain.cl_count);
2652	printk("id2.i_chain.cl_next_free_rec: %u\n",
2653	       fe->id2.i_chain.cl_next_free_rec);
2654	for(i = 0; i < fe->id2.i_chain.cl_next_free_rec; i++) {
2655		printk("fe->id2.i_chain.cl_recs[%d].c_free:  %u\n", i,
2656		       fe->id2.i_chain.cl_recs[i].c_free);
2657		printk("fe->id2.i_chain.cl_recs[%d].c_total: %u\n", i,
2658		       fe->id2.i_chain.cl_recs[i].c_total);
2659		printk("fe->id2.i_chain.cl_recs[%d].c_blkno: %llu\n", i,
2660		       (unsigned long long)fe->id2.i_chain.cl_recs[i].c_blkno);
2661	}
2662}
2663
2664/*
2665 * For a given allocation, determine which allocators will need to be
2666 * accessed, and lock them, reserving the appropriate number of bits.
2667 *
2668 * Sparse file systems call this from ocfs2_write_begin_nolock()
2669 * and ocfs2_allocate_unwritten_extents().
2670 *
2671 * File systems which don't support holes call this from
2672 * ocfs2_extend_allocation().
2673 */
2674int ocfs2_lock_allocators(struct inode *inode,
2675			  struct ocfs2_extent_tree *et,
2676			  u32 clusters_to_add, u32 extents_to_split,
2677			  struct ocfs2_alloc_context **data_ac,
2678			  struct ocfs2_alloc_context **meta_ac)
2679{
2680	int ret = 0, num_free_extents;
2681	unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2682	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2683
2684	*meta_ac = NULL;
2685	if (data_ac)
2686		*data_ac = NULL;
2687
2688	BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2689
2690	num_free_extents = ocfs2_num_free_extents(osb, et);
2691	if (num_free_extents < 0) {
2692		ret = num_free_extents;
2693		mlog_errno(ret);
2694		goto out;
2695	}
2696
2697	/*
2698	 * Sparse allocation file systems need to be more conservative
2699	 * with reserving room for expansion - the actual allocation
2700	 * happens while we've got a journal handle open so re-taking
2701	 * a cluster lock (because we ran out of room for another
2702	 * extent) will violate ordering rules.
2703	 *
2704	 * Most of the time we'll only be seeing this 1 cluster at a time
2705	 * anyway.
2706	 *
2707	 * Always lock for any unwritten extents - we might want to
2708	 * add blocks during a split.
2709	 */
2710	if (!num_free_extents ||
2711	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2712		ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2713		if (ret < 0) {
2714			if (ret != -ENOSPC)
2715				mlog_errno(ret);
2716			goto out;
2717		}
2718	}
2719
2720	if (clusters_to_add == 0)
2721		goto out;
2722
2723	ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2724	if (ret < 0) {
2725		if (ret != -ENOSPC)
2726			mlog_errno(ret);
2727		goto out;
2728	}
2729
2730out:
2731	if (ret) {
2732		if (*meta_ac) {
2733			ocfs2_free_alloc_context(*meta_ac);
2734			*meta_ac = NULL;
2735		}
2736
2737		/*
2738		 * We cannot have an error and a non null *data_ac.
2739		 */
2740	}
2741
2742	return ret;
2743}
2744
2745/*
2746 * Read the inode specified by blkno to get suballoc_slot and
2747 * suballoc_bit.
2748 */
2749static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2750				       u16 *suballoc_slot, u64 *group_blkno,
2751				       u16 *suballoc_bit)
2752{
2753	int status;
2754	struct buffer_head *inode_bh = NULL;
2755	struct ocfs2_dinode *inode_fe;
2756
2757	trace_ocfs2_get_suballoc_slot_bit((unsigned long long)blkno);
2758
2759	/* dirty read disk */
2760	status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2761	if (status < 0) {
2762		mlog(ML_ERROR, "read block %llu failed %d\n",
2763		     (unsigned long long)blkno, status);
2764		goto bail;
2765	}
2766
2767	inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2768	if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2769		mlog(ML_ERROR, "invalid inode %llu requested\n",
2770		     (unsigned long long)blkno);
2771		status = -EINVAL;
2772		goto bail;
2773	}
2774
2775	if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2776	    (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2777		mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2778		     (unsigned long long)blkno,
2779		     (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2780		status = -EINVAL;
2781		goto bail;
2782	}
2783
2784	if (suballoc_slot)
2785		*suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2786	if (suballoc_bit)
2787		*suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2788	if (group_blkno)
2789		*group_blkno = le64_to_cpu(inode_fe->i_suballoc_loc);
2790
2791bail:
2792	brelse(inode_bh);
2793
2794	if (status)
2795		mlog_errno(status);
2796	return status;
2797}
2798
2799/*
2800 * test whether bit is SET in allocator bitmap or not.  on success, 0
2801 * is returned and *res is 1 for SET; 0 otherwise.  when fails, errno
2802 * is returned and *res is meaningless.  Call this after you have
2803 * cluster locked against suballoc, or you may get a result based on
2804 * non-up2date contents
2805 */
2806static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2807				   struct inode *suballoc,
2808				   struct buffer_head *alloc_bh,
2809				   u64 group_blkno, u64 blkno,
2810				   u16 bit, int *res)
2811{
2812	struct ocfs2_dinode *alloc_di;
2813	struct ocfs2_group_desc *group;
2814	struct buffer_head *group_bh = NULL;
2815	u64 bg_blkno;
2816	int status;
2817
2818	trace_ocfs2_test_suballoc_bit((unsigned long long)blkno,
2819				      (unsigned int)bit);
2820
2821	alloc_di = (struct ocfs2_dinode *)alloc_bh->b_data;
2822	if ((bit + 1) > ocfs2_bits_per_group(&alloc_di->id2.i_chain)) {
2823		mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2824		     (unsigned int)bit,
2825		     ocfs2_bits_per_group(&alloc_di->id2.i_chain));
2826		status = -EINVAL;
2827		goto bail;
2828	}
2829
2830	bg_blkno = group_blkno ? group_blkno :
2831		   ocfs2_which_suballoc_group(blkno, bit);
2832	status = ocfs2_read_group_descriptor(suballoc, alloc_di, bg_blkno,
2833					     &group_bh);
2834	if (status < 0) {
2835		mlog(ML_ERROR, "read group %llu failed %d\n",
2836		     (unsigned long long)bg_blkno, status);
2837		goto bail;
2838	}
2839
2840	group = (struct ocfs2_group_desc *) group_bh->b_data;
2841	*res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2842
2843bail:
2844	brelse(group_bh);
2845
2846	if (status)
2847		mlog_errno(status);
2848	return status;
2849}
2850
2851/*
2852 * Test if the bit representing this inode (blkno) is set in the
2853 * suballocator.
2854 *
2855 * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2856 *
2857 * In the event of failure, a negative value is returned and *res is
2858 * meaningless.
2859 *
2860 * Callers must make sure to hold nfs_sync_lock to prevent
2861 * ocfs2_delete_inode() on another node from accessing the same
2862 * suballocator concurrently.
2863 */
2864int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2865{
2866	int status;
2867	u64 group_blkno = 0;
2868	u16 suballoc_bit = 0, suballoc_slot = 0;
2869	struct inode *inode_alloc_inode;
2870	struct buffer_head *alloc_bh = NULL;
2871
2872	trace_ocfs2_test_inode_bit((unsigned long long)blkno);
2873
2874	status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2875					     &group_blkno, &suballoc_bit);
2876	if (status < 0) {
2877		mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2878		goto bail;
2879	}
2880
2881	inode_alloc_inode =
2882		ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE,
2883					    suballoc_slot);
 
 
 
2884	if (!inode_alloc_inode) {
2885		/* the error code could be inaccurate, but we are not able to
2886		 * get the correct one. */
2887		status = -EINVAL;
2888		mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2889		     (u32)suballoc_slot);
2890		goto bail;
2891	}
2892
2893	mutex_lock(&inode_alloc_inode->i_mutex);
2894	status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2895	if (status < 0) {
2896		mutex_unlock(&inode_alloc_inode->i_mutex);
2897		iput(inode_alloc_inode);
2898		mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2899		     (u32)suballoc_slot, status);
2900		goto bail;
2901	}
2902
2903	status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2904					 group_blkno, blkno, suballoc_bit, res);
2905	if (status < 0)
2906		mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2907
2908	ocfs2_inode_unlock(inode_alloc_inode, 0);
2909	mutex_unlock(&inode_alloc_inode->i_mutex);
2910
2911	iput(inode_alloc_inode);
2912	brelse(alloc_bh);
2913bail:
2914	if (status)
2915		mlog_errno(status);
2916	return status;
2917}
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
 
   3 * suballoc.c
   4 *
   5 * metadata alloc and free
   6 * Inspired by ext3 block groups.
   7 *
   8 * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   9 */
  10
  11#include <linux/fs.h>
  12#include <linux/types.h>
  13#include <linux/slab.h>
  14#include <linux/highmem.h>
  15
  16#include <cluster/masklog.h>
  17
  18#include "ocfs2.h"
  19
  20#include "alloc.h"
  21#include "blockcheck.h"
  22#include "dlmglue.h"
  23#include "inode.h"
  24#include "journal.h"
  25#include "localalloc.h"
  26#include "suballoc.h"
  27#include "super.h"
  28#include "sysfile.h"
  29#include "uptodate.h"
  30#include "ocfs2_trace.h"
  31
  32#include "buffer_head_io.h"
  33
  34#define NOT_ALLOC_NEW_GROUP		0
  35#define ALLOC_NEW_GROUP			0x1
  36#define ALLOC_GROUPS_FROM_GLOBAL	0x2
  37
  38#define OCFS2_MAX_TO_STEAL		1024
  39
  40struct ocfs2_suballoc_result {
  41	u64		sr_bg_blkno;	/* The bg we allocated from.  Set
  42					   to 0 when a block group is
  43					   contiguous. */
  44	u64		sr_bg_stable_blkno; /*
  45					     * Doesn't change, always
  46					     * set to target block
  47					     * group descriptor
  48					     * block.
  49					     */
  50	u64		sr_blkno;	/* The first allocated block */
  51	unsigned int	sr_bit_offset;	/* The bit in the bg */
  52	unsigned int	sr_bits;	/* How many bits we claimed */
  53	unsigned int	sr_max_contig_bits; /* The length for contiguous
  54					     * free bits, only available
  55					     * for cluster group
  56					     */
  57};
  58
  59static u64 ocfs2_group_from_res(struct ocfs2_suballoc_result *res)
  60{
  61	if (res->sr_blkno == 0)
  62		return 0;
  63
  64	if (res->sr_bg_blkno)
  65		return res->sr_bg_blkno;
  66
  67	return ocfs2_which_suballoc_group(res->sr_blkno, res->sr_bit_offset);
  68}
  69
 
 
  70static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
  71static int ocfs2_block_group_fill(handle_t *handle,
  72				  struct inode *alloc_inode,
  73				  struct buffer_head *bg_bh,
  74				  u64 group_blkno,
  75				  unsigned int group_clusters,
  76				  u16 my_chain,
  77				  struct ocfs2_chain_list *cl);
  78static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
  79				   struct inode *alloc_inode,
  80				   struct buffer_head *bh,
  81				   u64 max_block,
  82				   u64 *last_alloc_group,
  83				   int flags);
  84
  85static int ocfs2_cluster_group_search(struct inode *inode,
  86				      struct buffer_head *group_bh,
  87				      u32 bits_wanted, u32 min_bits,
  88				      u64 max_block,
  89				      struct ocfs2_suballoc_result *res);
  90static int ocfs2_block_group_search(struct inode *inode,
  91				    struct buffer_head *group_bh,
  92				    u32 bits_wanted, u32 min_bits,
  93				    u64 max_block,
  94				    struct ocfs2_suballoc_result *res);
  95static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
  96				     handle_t *handle,
  97				     u32 bits_wanted,
  98				     u32 min_bits,
  99				     struct ocfs2_suballoc_result *res);
 100static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
 101					 int nr);
 102static int ocfs2_relink_block_group(handle_t *handle,
 103				    struct inode *alloc_inode,
 104				    struct buffer_head *fe_bh,
 105				    struct buffer_head *bg_bh,
 106				    struct buffer_head *prev_bg_bh,
 107				    u16 chain);
 108static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
 109						     u32 wanted);
 110static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
 111						   u64 bg_blkno,
 112						   u16 bg_bit_off);
 113static inline void ocfs2_block_to_cluster_group(struct inode *inode,
 114						u64 data_blkno,
 115						u64 *bg_blkno,
 116						u16 *bg_bit_off);
 117static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 118					     u32 bits_wanted, u64 max_block,
 119					     int flags,
 120					     struct ocfs2_alloc_context **ac);
 121
 122void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
 123{
 124	struct inode *inode = ac->ac_inode;
 125
 126	if (inode) {
 127		if (ac->ac_which != OCFS2_AC_USE_LOCAL)
 128			ocfs2_inode_unlock(inode, 1);
 129
 130		inode_unlock(inode);
 131
 132		iput(inode);
 133		ac->ac_inode = NULL;
 134	}
 135	brelse(ac->ac_bh);
 136	ac->ac_bh = NULL;
 137	ac->ac_resv = NULL;
 138	kfree(ac->ac_find_loc_priv);
 139	ac->ac_find_loc_priv = NULL;
 
 
 140}
 141
 142void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
 143{
 144	ocfs2_free_ac_resource(ac);
 145	kfree(ac);
 146}
 147
 148static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
 149{
 150	return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
 151}
 152
 153#define do_error(fmt, ...)						\
 154do {									\
 155	if (resize)							\
 156		mlog(ML_ERROR, fmt, ##__VA_ARGS__);			\
 157	else								\
 158		return ocfs2_error(sb, fmt, ##__VA_ARGS__);		\
 159} while (0)
 160
 161static int ocfs2_validate_gd_self(struct super_block *sb,
 162				  struct buffer_head *bh,
 163				  int resize)
 164{
 165	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 166
 167	if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
 168		do_error("Group descriptor #%llu has bad signature %.*s\n",
 169			 (unsigned long long)bh->b_blocknr, 7,
 170			 gd->bg_signature);
 
 171	}
 172
 173	if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
 174		do_error("Group descriptor #%llu has an invalid bg_blkno of %llu\n",
 
 175			 (unsigned long long)bh->b_blocknr,
 176			 (unsigned long long)le64_to_cpu(gd->bg_blkno));
 
 177	}
 178
 179	if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
 180		do_error("Group descriptor #%llu has an invalid fs_generation of #%u\n",
 
 181			 (unsigned long long)bh->b_blocknr,
 182			 le32_to_cpu(gd->bg_generation));
 
 183	}
 184
 185	if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
 186		do_error("Group descriptor #%llu has bit count %u but claims that %u are free\n",
 
 187			 (unsigned long long)bh->b_blocknr,
 188			 le16_to_cpu(gd->bg_bits),
 189			 le16_to_cpu(gd->bg_free_bits_count));
 
 190	}
 191
 192	if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
 193		do_error("Group descriptor #%llu has bit count %u but max bitmap bits of %u\n",
 
 194			 (unsigned long long)bh->b_blocknr,
 195			 le16_to_cpu(gd->bg_bits),
 196			 8 * le16_to_cpu(gd->bg_size));
 
 197	}
 198
 199	return 0;
 200}
 201
 202static int ocfs2_validate_gd_parent(struct super_block *sb,
 203				    struct ocfs2_dinode *di,
 204				    struct buffer_head *bh,
 205				    int resize)
 206{
 207	unsigned int max_bits;
 208	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 209
 210	if (di->i_blkno != gd->bg_parent_dinode) {
 211		do_error("Group descriptor #%llu has bad parent pointer (%llu, expected %llu)\n",
 
 212			 (unsigned long long)bh->b_blocknr,
 213			 (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
 214			 (unsigned long long)le64_to_cpu(di->i_blkno));
 
 215	}
 216
 217	max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
 218	if (le16_to_cpu(gd->bg_bits) > max_bits) {
 219		do_error("Group descriptor #%llu has bit count of %u\n",
 220			 (unsigned long long)bh->b_blocknr,
 221			 le16_to_cpu(gd->bg_bits));
 
 222	}
 223
 224	/* In resize, we may meet the case bg_chain == cl_next_free_rec. */
 225	if ((le16_to_cpu(gd->bg_chain) >
 226	     le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) ||
 227	    ((le16_to_cpu(gd->bg_chain) ==
 228	     le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) && !resize)) {
 229		do_error("Group descriptor #%llu has bad chain %u\n",
 230			 (unsigned long long)bh->b_blocknr,
 231			 le16_to_cpu(gd->bg_chain));
 
 232	}
 233
 234	return 0;
 235}
 236
 237#undef do_error
 238
 239/*
 240 * This version only prints errors.  It does not fail the filesystem, and
 241 * exists only for resize.
 242 */
 243int ocfs2_check_group_descriptor(struct super_block *sb,
 244				 struct ocfs2_dinode *di,
 245				 struct buffer_head *bh)
 246{
 247	int rc;
 248	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 249
 250	BUG_ON(!buffer_uptodate(bh));
 251
 252	/*
 253	 * If the ecc fails, we return the error but otherwise
 254	 * leave the filesystem running.  We know any error is
 255	 * local to this block.
 256	 */
 257	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 258	if (rc) {
 259		mlog(ML_ERROR,
 260		     "Checksum failed for group descriptor %llu\n",
 261		     (unsigned long long)bh->b_blocknr);
 262	} else
 263		rc = ocfs2_validate_gd_self(sb, bh, 1);
 264	if (!rc)
 265		rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
 266
 267	return rc;
 268}
 269
 270static int ocfs2_validate_group_descriptor(struct super_block *sb,
 271					   struct buffer_head *bh)
 272{
 273	int rc;
 274	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 275
 276	trace_ocfs2_validate_group_descriptor(
 277					(unsigned long long)bh->b_blocknr);
 278
 279	BUG_ON(!buffer_uptodate(bh));
 280
 281	/*
 282	 * If the ecc fails, we return the error but otherwise
 283	 * leave the filesystem running.  We know any error is
 284	 * local to this block.
 285	 */
 286	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 287	if (rc)
 288		return rc;
 289
 290	/*
 291	 * Errors after here are fatal.
 292	 */
 293
 294	return ocfs2_validate_gd_self(sb, bh, 0);
 295}
 296
 297int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 298				u64 gd_blkno, struct buffer_head **bh)
 299{
 300	int rc;
 301	struct buffer_head *tmp = *bh;
 302
 303	rc = ocfs2_read_block(INODE_CACHE(inode), gd_blkno, &tmp,
 304			      ocfs2_validate_group_descriptor);
 305	if (rc)
 306		goto out;
 307
 308	rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
 309	if (rc) {
 310		brelse(tmp);
 311		goto out;
 312	}
 313
 314	/* If ocfs2_read_block() got us a new bh, pass it up. */
 315	if (!*bh)
 316		*bh = tmp;
 317
 318out:
 319	return rc;
 320}
 321
 322static void ocfs2_bg_discontig_add_extent(struct ocfs2_super *osb,
 323					  struct ocfs2_group_desc *bg,
 324					  struct ocfs2_chain_list *cl,
 325					  u64 p_blkno, unsigned int clusters)
 326{
 327	struct ocfs2_extent_list *el = &bg->bg_list;
 328	struct ocfs2_extent_rec *rec;
 329
 330	BUG_ON(!ocfs2_supports_discontig_bg(osb));
 331	if (!el->l_next_free_rec)
 332		el->l_count = cpu_to_le16(ocfs2_extent_recs_per_gd(osb->sb));
 333	rec = &el->l_recs[le16_to_cpu(el->l_next_free_rec)];
 334	rec->e_blkno = cpu_to_le64(p_blkno);
 335	rec->e_cpos = cpu_to_le32(le16_to_cpu(bg->bg_bits) /
 336				  le16_to_cpu(cl->cl_bpc));
 337	rec->e_leaf_clusters = cpu_to_le16(clusters);
 338	le16_add_cpu(&bg->bg_bits, clusters * le16_to_cpu(cl->cl_bpc));
 339	le16_add_cpu(&bg->bg_free_bits_count,
 340		     clusters * le16_to_cpu(cl->cl_bpc));
 341	le16_add_cpu(&el->l_next_free_rec, 1);
 342}
 343
 344static int ocfs2_block_group_fill(handle_t *handle,
 345				  struct inode *alloc_inode,
 346				  struct buffer_head *bg_bh,
 347				  u64 group_blkno,
 348				  unsigned int group_clusters,
 349				  u16 my_chain,
 350				  struct ocfs2_chain_list *cl)
 351{
 352	int status = 0;
 353	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 354	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 355	struct super_block * sb = alloc_inode->i_sb;
 356
 357	if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
 358		status = ocfs2_error(alloc_inode->i_sb,
 359				     "group block (%llu) != b_blocknr (%llu)\n",
 360				     (unsigned long long)group_blkno,
 361				     (unsigned long long) bg_bh->b_blocknr);
 
 362		goto bail;
 363	}
 364
 365	status = ocfs2_journal_access_gd(handle,
 366					 INODE_CACHE(alloc_inode),
 367					 bg_bh,
 368					 OCFS2_JOURNAL_ACCESS_CREATE);
 369	if (status < 0) {
 370		mlog_errno(status);
 371		goto bail;
 372	}
 373
 374	memset(bg, 0, sb->s_blocksize);
 375	strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
 376	bg->bg_generation = cpu_to_le32(osb->fs_generation);
 377	bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb, 1,
 378						osb->s_feature_incompat));
 379	bg->bg_chain = cpu_to_le16(my_chain);
 380	bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
 381	bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
 382	bg->bg_blkno = cpu_to_le64(group_blkno);
 383	if (group_clusters == le16_to_cpu(cl->cl_cpg))
 384		bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
 385	else
 386		ocfs2_bg_discontig_add_extent(osb, bg, cl, group_blkno,
 387					      group_clusters);
 388
 389	/* set the 1st bit in the bitmap to account for the descriptor block */
 390	ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
 391	bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
 392
 393	ocfs2_journal_dirty(handle, bg_bh);
 394
 395	/* There is no need to zero out or otherwise initialize the
 396	 * other blocks in a group - All valid FS metadata in a block
 397	 * group stores the superblock fs_generation value at
 398	 * allocation time. */
 399
 400bail:
 401	if (status)
 402		mlog_errno(status);
 403	return status;
 404}
 405
 406static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
 407{
 408	u16 curr, best;
 409
 410	best = curr = 0;
 411	while (curr < le16_to_cpu(cl->cl_count)) {
 412		if (le32_to_cpu(cl->cl_recs[best].c_total) >
 413		    le32_to_cpu(cl->cl_recs[curr].c_total))
 414			best = curr;
 415		curr++;
 416	}
 417	return best;
 418}
 419
 420static struct buffer_head *
 421ocfs2_block_group_alloc_contig(struct ocfs2_super *osb, handle_t *handle,
 422			       struct inode *alloc_inode,
 423			       struct ocfs2_alloc_context *ac,
 424			       struct ocfs2_chain_list *cl)
 425{
 426	int status;
 427	u32 bit_off, num_bits;
 428	u64 bg_blkno;
 429	struct buffer_head *bg_bh;
 430	unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
 431
 432	status = ocfs2_claim_clusters(handle, ac,
 433				      le16_to_cpu(cl->cl_cpg), &bit_off,
 434				      &num_bits);
 435	if (status < 0) {
 436		if (status != -ENOSPC)
 437			mlog_errno(status);
 438		goto bail;
 439	}
 440
 441	/* setup the group */
 442	bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 443	trace_ocfs2_block_group_alloc_contig(
 444	     (unsigned long long)bg_blkno, alloc_rec);
 445
 446	bg_bh = sb_getblk(osb->sb, bg_blkno);
 447	if (!bg_bh) {
 448		status = -ENOMEM;
 449		mlog_errno(status);
 450		goto bail;
 451	}
 452	ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
 453
 454	status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
 455					bg_blkno, num_bits, alloc_rec, cl);
 456	if (status < 0) {
 457		brelse(bg_bh);
 458		mlog_errno(status);
 459	}
 460
 461bail:
 462	return status ? ERR_PTR(status) : bg_bh;
 463}
 464
 465static int ocfs2_block_group_claim_bits(struct ocfs2_super *osb,
 466					handle_t *handle,
 467					struct ocfs2_alloc_context *ac,
 468					unsigned int min_bits,
 469					u32 *bit_off, u32 *num_bits)
 470{
 471	int status = 0;
 472
 473	while (min_bits) {
 474		status = ocfs2_claim_clusters(handle, ac, min_bits,
 475					      bit_off, num_bits);
 476		if (status != -ENOSPC)
 477			break;
 478
 479		min_bits >>= 1;
 480	}
 481
 482	return status;
 483}
 484
 485static int ocfs2_block_group_grow_discontig(handle_t *handle,
 486					    struct inode *alloc_inode,
 487					    struct buffer_head *bg_bh,
 488					    struct ocfs2_alloc_context *ac,
 489					    struct ocfs2_chain_list *cl,
 490					    unsigned int min_bits)
 491{
 492	int status;
 493	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 494	struct ocfs2_group_desc *bg =
 495		(struct ocfs2_group_desc *)bg_bh->b_data;
 496	unsigned int needed = le16_to_cpu(cl->cl_cpg) -
 497			 le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
 498	u32 p_cpos, clusters;
 499	u64 p_blkno;
 500	struct ocfs2_extent_list *el = &bg->bg_list;
 501
 502	status = ocfs2_journal_access_gd(handle,
 503					 INODE_CACHE(alloc_inode),
 504					 bg_bh,
 505					 OCFS2_JOURNAL_ACCESS_CREATE);
 506	if (status < 0) {
 507		mlog_errno(status);
 508		goto bail;
 509	}
 510
 511	while ((needed > 0) && (le16_to_cpu(el->l_next_free_rec) <
 512				le16_to_cpu(el->l_count))) {
 513		if (min_bits > needed)
 514			min_bits = needed;
 515		status = ocfs2_block_group_claim_bits(osb, handle, ac,
 516						      min_bits, &p_cpos,
 517						      &clusters);
 518		if (status < 0) {
 519			if (status != -ENOSPC)
 520				mlog_errno(status);
 521			goto bail;
 522		}
 523		p_blkno = ocfs2_clusters_to_blocks(osb->sb, p_cpos);
 524		ocfs2_bg_discontig_add_extent(osb, bg, cl, p_blkno,
 525					      clusters);
 526
 527		min_bits = clusters;
 528		needed = le16_to_cpu(cl->cl_cpg) -
 529			 le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
 530	}
 531
 532	if (needed > 0) {
 533		/*
 534		 * We have used up all the extent rec but can't fill up
 535		 * the cpg. So bail out.
 536		 */
 537		status = -ENOSPC;
 538		goto bail;
 539	}
 540
 541	ocfs2_journal_dirty(handle, bg_bh);
 542
 543bail:
 544	return status;
 545}
 546
 547static void ocfs2_bg_alloc_cleanup(handle_t *handle,
 548				   struct ocfs2_alloc_context *cluster_ac,
 549				   struct inode *alloc_inode,
 550				   struct buffer_head *bg_bh)
 551{
 552	int i, ret;
 553	struct ocfs2_group_desc *bg;
 554	struct ocfs2_extent_list *el;
 555	struct ocfs2_extent_rec *rec;
 556
 557	if (!bg_bh)
 558		return;
 559
 560	bg = (struct ocfs2_group_desc *)bg_bh->b_data;
 561	el = &bg->bg_list;
 562	for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
 563		rec = &el->l_recs[i];
 564		ret = ocfs2_free_clusters(handle, cluster_ac->ac_inode,
 565					  cluster_ac->ac_bh,
 566					  le64_to_cpu(rec->e_blkno),
 567					  le16_to_cpu(rec->e_leaf_clusters));
 568		if (ret)
 569			mlog_errno(ret);
 570		/* Try all the clusters to free */
 571	}
 572
 573	ocfs2_remove_from_cache(INODE_CACHE(alloc_inode), bg_bh);
 574	brelse(bg_bh);
 575}
 576
 577static struct buffer_head *
 578ocfs2_block_group_alloc_discontig(handle_t *handle,
 579				  struct inode *alloc_inode,
 580				  struct ocfs2_alloc_context *ac,
 581				  struct ocfs2_chain_list *cl)
 582{
 583	int status;
 584	u32 bit_off, num_bits;
 585	u64 bg_blkno;
 586	unsigned int min_bits = le16_to_cpu(cl->cl_cpg) >> 1;
 587	struct buffer_head *bg_bh = NULL;
 588	unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
 589	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 590
 591	if (!ocfs2_supports_discontig_bg(osb)) {
 592		status = -ENOSPC;
 593		goto bail;
 594	}
 595
 596	status = ocfs2_extend_trans(handle,
 597				    ocfs2_calc_bg_discontig_credits(osb->sb));
 598	if (status) {
 599		mlog_errno(status);
 600		goto bail;
 601	}
 602
 603	/*
 604	 * We're going to be grabbing from multiple cluster groups.
 605	 * We don't have enough credits to relink them all, and the
 606	 * cluster groups will be staying in cache for the duration of
 607	 * this operation.
 608	 */
 609	ac->ac_disable_chain_relink = 1;
 610
 611	/* Claim the first region */
 612	status = ocfs2_block_group_claim_bits(osb, handle, ac, min_bits,
 613					      &bit_off, &num_bits);
 614	if (status < 0) {
 615		if (status != -ENOSPC)
 616			mlog_errno(status);
 617		goto bail;
 618	}
 619	min_bits = num_bits;
 620
 621	/* setup the group */
 622	bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 623	trace_ocfs2_block_group_alloc_discontig(
 624				(unsigned long long)bg_blkno, alloc_rec);
 625
 626	bg_bh = sb_getblk(osb->sb, bg_blkno);
 627	if (!bg_bh) {
 628		status = -ENOMEM;
 629		mlog_errno(status);
 630		goto bail;
 631	}
 632	ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
 633
 634	status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
 635					bg_blkno, num_bits, alloc_rec, cl);
 636	if (status < 0) {
 637		mlog_errno(status);
 638		goto bail;
 639	}
 640
 641	status = ocfs2_block_group_grow_discontig(handle, alloc_inode,
 642						  bg_bh, ac, cl, min_bits);
 643	if (status)
 644		mlog_errno(status);
 645
 646bail:
 647	if (status)
 648		ocfs2_bg_alloc_cleanup(handle, ac, alloc_inode, bg_bh);
 649	return status ? ERR_PTR(status) : bg_bh;
 650}
 651
 652/*
 653 * We expect the block group allocator to already be locked.
 654 */
 655static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
 656				   struct inode *alloc_inode,
 657				   struct buffer_head *bh,
 658				   u64 max_block,
 659				   u64 *last_alloc_group,
 660				   int flags)
 661{
 662	int status, credits;
 663	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
 664	struct ocfs2_chain_list *cl;
 665	struct ocfs2_alloc_context *ac = NULL;
 666	handle_t *handle = NULL;
 667	u16 alloc_rec;
 668	struct buffer_head *bg_bh = NULL;
 669	struct ocfs2_group_desc *bg;
 670
 671	BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
 672
 673	cl = &fe->id2.i_chain;
 674	status = ocfs2_reserve_clusters_with_limit(osb,
 675						   le16_to_cpu(cl->cl_cpg),
 676						   max_block, flags, &ac);
 677	if (status < 0) {
 678		if (status != -ENOSPC)
 679			mlog_errno(status);
 680		goto bail;
 681	}
 682
 683	credits = ocfs2_calc_group_alloc_credits(osb->sb,
 684						 le16_to_cpu(cl->cl_cpg));
 685	handle = ocfs2_start_trans(osb, credits);
 686	if (IS_ERR(handle)) {
 687		status = PTR_ERR(handle);
 688		handle = NULL;
 689		mlog_errno(status);
 690		goto bail;
 691	}
 692
 693	if (last_alloc_group && *last_alloc_group != 0) {
 694		trace_ocfs2_block_group_alloc(
 695				(unsigned long long)*last_alloc_group);
 696		ac->ac_last_group = *last_alloc_group;
 697	}
 698
 699	bg_bh = ocfs2_block_group_alloc_contig(osb, handle, alloc_inode,
 700					       ac, cl);
 701	if (PTR_ERR(bg_bh) == -ENOSPC)
 702		bg_bh = ocfs2_block_group_alloc_discontig(handle,
 703							  alloc_inode,
 704							  ac, cl);
 705	if (IS_ERR(bg_bh)) {
 706		status = PTR_ERR(bg_bh);
 707		bg_bh = NULL;
 708		if (status != -ENOSPC)
 709			mlog_errno(status);
 710		goto bail;
 711	}
 712	bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 713
 714	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
 715					 bh, OCFS2_JOURNAL_ACCESS_WRITE);
 716	if (status < 0) {
 717		mlog_errno(status);
 718		goto bail;
 719	}
 720
 721	alloc_rec = le16_to_cpu(bg->bg_chain);
 722	le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
 723		     le16_to_cpu(bg->bg_free_bits_count));
 724	le32_add_cpu(&cl->cl_recs[alloc_rec].c_total,
 725		     le16_to_cpu(bg->bg_bits));
 726	cl->cl_recs[alloc_rec].c_blkno = bg->bg_blkno;
 727	if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
 728		le16_add_cpu(&cl->cl_next_free_rec, 1);
 729
 730	le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
 731					le16_to_cpu(bg->bg_free_bits_count));
 732	le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
 733	le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
 734
 735	ocfs2_journal_dirty(handle, bh);
 736
 737	spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
 738	OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 739	fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
 740					     le32_to_cpu(fe->i_clusters)));
 741	spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
 742	i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
 743	alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
 744	ocfs2_update_inode_fsync_trans(handle, alloc_inode, 0);
 745
 746	status = 0;
 747
 748	/* save the new last alloc group so that the caller can cache it. */
 749	if (last_alloc_group)
 750		*last_alloc_group = ac->ac_last_group;
 751
 752bail:
 753	if (handle)
 754		ocfs2_commit_trans(osb, handle);
 755
 756	if (ac)
 757		ocfs2_free_alloc_context(ac);
 758
 759	brelse(bg_bh);
 760
 761	if (status)
 762		mlog_errno(status);
 763	return status;
 764}
 765
 766static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
 767				       struct ocfs2_alloc_context *ac,
 768				       int type,
 769				       u32 slot,
 770				       u64 *last_alloc_group,
 771				       int flags)
 772{
 773	int status;
 774	u32 bits_wanted = ac->ac_bits_wanted;
 775	struct inode *alloc_inode;
 776	struct buffer_head *bh = NULL;
 777	struct ocfs2_dinode *fe;
 778	u32 free_bits;
 779
 780	alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
 781	if (!alloc_inode) {
 782		mlog_errno(-EINVAL);
 783		return -EINVAL;
 784	}
 785
 786	inode_lock(alloc_inode);
 787
 788	status = ocfs2_inode_lock(alloc_inode, &bh, 1);
 789	if (status < 0) {
 790		inode_unlock(alloc_inode);
 791		iput(alloc_inode);
 792
 793		mlog_errno(status);
 794		return status;
 795	}
 796
 797	ac->ac_inode = alloc_inode;
 798	ac->ac_alloc_slot = slot;
 799
 800	fe = (struct ocfs2_dinode *) bh->b_data;
 801
 802	/* The bh was validated by the inode read inside
 803	 * ocfs2_inode_lock().  Any corruption is a code bug. */
 804	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
 805
 806	if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
 807		status = ocfs2_error(alloc_inode->i_sb,
 808				     "Invalid chain allocator %llu\n",
 809				     (unsigned long long)le64_to_cpu(fe->i_blkno));
 810		goto bail;
 811	}
 812
 813	free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
 814		le32_to_cpu(fe->id1.bitmap1.i_used);
 815
 816	if (bits_wanted > free_bits) {
 817		/* cluster bitmap never grows */
 818		if (ocfs2_is_cluster_bitmap(alloc_inode)) {
 819			trace_ocfs2_reserve_suballoc_bits_nospc(bits_wanted,
 820								free_bits);
 821			status = -ENOSPC;
 822			goto bail;
 823		}
 824
 825		if (!(flags & ALLOC_NEW_GROUP)) {
 826			trace_ocfs2_reserve_suballoc_bits_no_new_group(
 827						slot, bits_wanted, free_bits);
 828			status = -ENOSPC;
 829			goto bail;
 830		}
 831
 832		status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
 833						 ac->ac_max_block,
 834						 last_alloc_group, flags);
 835		if (status < 0) {
 836			if (status != -ENOSPC)
 837				mlog_errno(status);
 838			goto bail;
 839		}
 840		atomic_inc(&osb->alloc_stats.bg_extends);
 841
 842		/* You should never ask for this much metadata */
 843		BUG_ON(bits_wanted >
 844		       (le32_to_cpu(fe->id1.bitmap1.i_total)
 845			- le32_to_cpu(fe->id1.bitmap1.i_used)));
 846	}
 847
 848	get_bh(bh);
 849	ac->ac_bh = bh;
 850bail:
 851	brelse(bh);
 852
 853	if (status)
 854		mlog_errno(status);
 855	return status;
 856}
 857
 858static void ocfs2_init_inode_steal_slot(struct ocfs2_super *osb)
 859{
 860	spin_lock(&osb->osb_lock);
 861	osb->s_inode_steal_slot = OCFS2_INVALID_SLOT;
 862	spin_unlock(&osb->osb_lock);
 863	atomic_set(&osb->s_num_inodes_stolen, 0);
 864}
 865
 866static void ocfs2_init_meta_steal_slot(struct ocfs2_super *osb)
 867{
 868	spin_lock(&osb->osb_lock);
 869	osb->s_meta_steal_slot = OCFS2_INVALID_SLOT;
 870	spin_unlock(&osb->osb_lock);
 871	atomic_set(&osb->s_num_meta_stolen, 0);
 872}
 873
 874void ocfs2_init_steal_slots(struct ocfs2_super *osb)
 875{
 876	ocfs2_init_inode_steal_slot(osb);
 877	ocfs2_init_meta_steal_slot(osb);
 878}
 879
 880static void __ocfs2_set_steal_slot(struct ocfs2_super *osb, int slot, int type)
 881{
 882	spin_lock(&osb->osb_lock);
 883	if (type == INODE_ALLOC_SYSTEM_INODE)
 884		osb->s_inode_steal_slot = (u16)slot;
 885	else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 886		osb->s_meta_steal_slot = (u16)slot;
 887	spin_unlock(&osb->osb_lock);
 888}
 889
 890static int __ocfs2_get_steal_slot(struct ocfs2_super *osb, int type)
 891{
 892	int slot = OCFS2_INVALID_SLOT;
 893
 894	spin_lock(&osb->osb_lock);
 895	if (type == INODE_ALLOC_SYSTEM_INODE)
 896		slot = osb->s_inode_steal_slot;
 897	else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 898		slot = osb->s_meta_steal_slot;
 899	spin_unlock(&osb->osb_lock);
 900
 901	return slot;
 902}
 903
 904static int ocfs2_get_inode_steal_slot(struct ocfs2_super *osb)
 905{
 906	return __ocfs2_get_steal_slot(osb, INODE_ALLOC_SYSTEM_INODE);
 907}
 908
 909static int ocfs2_get_meta_steal_slot(struct ocfs2_super *osb)
 910{
 911	return __ocfs2_get_steal_slot(osb, EXTENT_ALLOC_SYSTEM_INODE);
 912}
 913
 914static int ocfs2_steal_resource(struct ocfs2_super *osb,
 915				struct ocfs2_alloc_context *ac,
 916				int type)
 917{
 918	int i, status = -ENOSPC;
 919	int slot = __ocfs2_get_steal_slot(osb, type);
 920
 921	/* Start to steal resource from the first slot after ours. */
 922	if (slot == OCFS2_INVALID_SLOT)
 923		slot = osb->slot_num + 1;
 924
 925	for (i = 0; i < osb->max_slots; i++, slot++) {
 926		if (slot == osb->max_slots)
 927			slot = 0;
 928
 929		if (slot == osb->slot_num)
 930			continue;
 931
 932		status = ocfs2_reserve_suballoc_bits(osb, ac,
 933						     type,
 934						     (u32)slot, NULL,
 935						     NOT_ALLOC_NEW_GROUP);
 936		if (status >= 0) {
 937			__ocfs2_set_steal_slot(osb, slot, type);
 938			break;
 939		}
 940
 941		ocfs2_free_ac_resource(ac);
 942	}
 943
 944	return status;
 945}
 946
 947static int ocfs2_steal_inode(struct ocfs2_super *osb,
 948			     struct ocfs2_alloc_context *ac)
 949{
 950	return ocfs2_steal_resource(osb, ac, INODE_ALLOC_SYSTEM_INODE);
 951}
 952
 953static int ocfs2_steal_meta(struct ocfs2_super *osb,
 954			    struct ocfs2_alloc_context *ac)
 955{
 956	return ocfs2_steal_resource(osb, ac, EXTENT_ALLOC_SYSTEM_INODE);
 957}
 958
 959int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
 960				      int blocks,
 961				      struct ocfs2_alloc_context **ac)
 962{
 963	int status;
 964	int slot = ocfs2_get_meta_steal_slot(osb);
 965
 966	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 967	if (!(*ac)) {
 968		status = -ENOMEM;
 969		mlog_errno(status);
 970		goto bail;
 971	}
 972
 973	(*ac)->ac_bits_wanted = blocks;
 974	(*ac)->ac_which = OCFS2_AC_USE_META;
 975	(*ac)->ac_group_search = ocfs2_block_group_search;
 976
 977	if (slot != OCFS2_INVALID_SLOT &&
 978		atomic_read(&osb->s_num_meta_stolen) < OCFS2_MAX_TO_STEAL)
 979		goto extent_steal;
 980
 981	atomic_set(&osb->s_num_meta_stolen, 0);
 982	status = ocfs2_reserve_suballoc_bits(osb, (*ac),
 983					     EXTENT_ALLOC_SYSTEM_INODE,
 984					     (u32)osb->slot_num, NULL,
 985					     ALLOC_GROUPS_FROM_GLOBAL|ALLOC_NEW_GROUP);
 986
 987
 988	if (status >= 0) {
 989		status = 0;
 990		if (slot != OCFS2_INVALID_SLOT)
 991			ocfs2_init_meta_steal_slot(osb);
 992		goto bail;
 993	} else if (status < 0 && status != -ENOSPC) {
 994		mlog_errno(status);
 995		goto bail;
 996	}
 997
 998	ocfs2_free_ac_resource(*ac);
 999
1000extent_steal:
1001	status = ocfs2_steal_meta(osb, *ac);
1002	atomic_inc(&osb->s_num_meta_stolen);
1003	if (status < 0) {
1004		if (status != -ENOSPC)
1005			mlog_errno(status);
1006		goto bail;
1007	}
1008
1009	status = 0;
1010bail:
1011	if ((status < 0) && *ac) {
1012		ocfs2_free_alloc_context(*ac);
1013		*ac = NULL;
1014	}
1015
1016	if (status)
1017		mlog_errno(status);
1018	return status;
1019}
1020
1021int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
1022			       struct ocfs2_extent_list *root_el,
1023			       struct ocfs2_alloc_context **ac)
1024{
1025	return ocfs2_reserve_new_metadata_blocks(osb,
1026					ocfs2_extend_meta_needed(root_el),
1027					ac);
1028}
1029
1030int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
1031			    struct ocfs2_alloc_context **ac)
1032{
1033	int status;
1034	int slot = ocfs2_get_inode_steal_slot(osb);
1035	u64 alloc_group;
1036
1037	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1038	if (!(*ac)) {
1039		status = -ENOMEM;
1040		mlog_errno(status);
1041		goto bail;
1042	}
1043
1044	(*ac)->ac_bits_wanted = 1;
1045	(*ac)->ac_which = OCFS2_AC_USE_INODE;
1046
1047	(*ac)->ac_group_search = ocfs2_block_group_search;
1048
1049	/*
1050	 * stat(2) can't handle i_ino > 32bits, so we tell the
1051	 * lower levels not to allocate us a block group past that
1052	 * limit.  The 'inode64' mount option avoids this behavior.
1053	 */
1054	if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
1055		(*ac)->ac_max_block = (u32)~0U;
1056
1057	/*
1058	 * slot is set when we successfully steal inode from other nodes.
1059	 * It is reset in 3 places:
1060	 * 1. when we flush the truncate log
1061	 * 2. when we complete local alloc recovery.
1062	 * 3. when we successfully allocate from our own slot.
1063	 * After it is set, we will go on stealing inodes until we find the
1064	 * need to check our slots to see whether there is some space for us.
1065	 */
1066	if (slot != OCFS2_INVALID_SLOT &&
1067	    atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_TO_STEAL)
1068		goto inode_steal;
1069
1070	atomic_set(&osb->s_num_inodes_stolen, 0);
1071	alloc_group = osb->osb_inode_alloc_group;
1072	status = ocfs2_reserve_suballoc_bits(osb, *ac,
1073					     INODE_ALLOC_SYSTEM_INODE,
1074					     (u32)osb->slot_num,
1075					     &alloc_group,
1076					     ALLOC_NEW_GROUP |
1077					     ALLOC_GROUPS_FROM_GLOBAL);
1078	if (status >= 0) {
1079		status = 0;
1080
1081		spin_lock(&osb->osb_lock);
1082		osb->osb_inode_alloc_group = alloc_group;
1083		spin_unlock(&osb->osb_lock);
1084		trace_ocfs2_reserve_new_inode_new_group(
1085			(unsigned long long)alloc_group);
1086
1087		/*
1088		 * Some inodes must be freed by us, so try to allocate
1089		 * from our own next time.
1090		 */
1091		if (slot != OCFS2_INVALID_SLOT)
1092			ocfs2_init_inode_steal_slot(osb);
1093		goto bail;
1094	} else if (status < 0 && status != -ENOSPC) {
1095		mlog_errno(status);
1096		goto bail;
1097	}
1098
1099	ocfs2_free_ac_resource(*ac);
1100
1101inode_steal:
1102	status = ocfs2_steal_inode(osb, *ac);
1103	atomic_inc(&osb->s_num_inodes_stolen);
1104	if (status < 0) {
1105		if (status != -ENOSPC)
1106			mlog_errno(status);
1107		goto bail;
1108	}
1109
1110	status = 0;
1111bail:
1112	if ((status < 0) && *ac) {
1113		ocfs2_free_alloc_context(*ac);
1114		*ac = NULL;
1115	}
1116
1117	if (status)
1118		mlog_errno(status);
1119	return status;
1120}
1121
1122/* local alloc code has to do the same thing, so rather than do this
1123 * twice.. */
1124int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
1125				      struct ocfs2_alloc_context *ac)
1126{
1127	int status;
1128
1129	ac->ac_which = OCFS2_AC_USE_MAIN;
1130	ac->ac_group_search = ocfs2_cluster_group_search;
1131
1132	status = ocfs2_reserve_suballoc_bits(osb, ac,
1133					     GLOBAL_BITMAP_SYSTEM_INODE,
1134					     OCFS2_INVALID_SLOT, NULL,
1135					     ALLOC_NEW_GROUP);
1136	if (status < 0 && status != -ENOSPC)
1137		mlog_errno(status);
 
 
1138
 
1139	return status;
1140}
1141
1142/* Callers don't need to care which bitmap (local alloc or main) to
1143 * use so we figure it out for them, but unfortunately this clutters
1144 * things a bit. */
1145static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
1146					     u32 bits_wanted, u64 max_block,
1147					     int flags,
1148					     struct ocfs2_alloc_context **ac)
1149{
1150	int status, ret = 0;
1151	int retried = 0;
1152
1153	*ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1154	if (!(*ac)) {
1155		status = -ENOMEM;
1156		mlog_errno(status);
1157		goto bail;
1158	}
1159
1160	(*ac)->ac_bits_wanted = bits_wanted;
1161	(*ac)->ac_max_block = max_block;
1162
1163	status = -ENOSPC;
1164	if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
1165	    ocfs2_alloc_should_use_local(osb, bits_wanted)) {
1166		status = ocfs2_reserve_local_alloc_bits(osb,
1167							bits_wanted,
1168							*ac);
1169		if ((status < 0) && (status != -ENOSPC)) {
1170			mlog_errno(status);
1171			goto bail;
1172		}
1173	}
1174
1175	if (status == -ENOSPC) {
1176retry:
1177		status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
1178		/* Retry if there is sufficient space cached in truncate log */
1179		if (status == -ENOSPC && !retried) {
1180			retried = 1;
1181			ocfs2_inode_unlock((*ac)->ac_inode, 1);
1182			inode_unlock((*ac)->ac_inode);
1183
1184			ret = ocfs2_try_to_free_truncate_log(osb, bits_wanted);
1185			if (ret == 1) {
1186				iput((*ac)->ac_inode);
1187				(*ac)->ac_inode = NULL;
1188				goto retry;
1189			}
1190
1191			if (ret < 0)
1192				mlog_errno(ret);
1193
1194			inode_lock((*ac)->ac_inode);
1195			ret = ocfs2_inode_lock((*ac)->ac_inode, NULL, 1);
1196			if (ret < 0) {
1197				mlog_errno(ret);
1198				inode_unlock((*ac)->ac_inode);
1199				iput((*ac)->ac_inode);
1200				(*ac)->ac_inode = NULL;
1201				goto bail;
1202			}
1203		}
1204		if (status < 0) {
1205			if (status != -ENOSPC)
1206				mlog_errno(status);
1207			goto bail;
1208		}
1209	}
1210
1211	status = 0;
1212bail:
1213	if ((status < 0) && *ac) {
1214		ocfs2_free_alloc_context(*ac);
1215		*ac = NULL;
1216	}
1217
1218	if (status)
1219		mlog_errno(status);
1220	return status;
1221}
1222
1223int ocfs2_reserve_clusters(struct ocfs2_super *osb,
1224			   u32 bits_wanted,
1225			   struct ocfs2_alloc_context **ac)
1226{
1227	return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
1228						 ALLOC_NEW_GROUP, ac);
1229}
1230
1231/*
1232 * More or less lifted from ext3. I'll leave their description below:
1233 *
1234 * "For ext3 allocations, we must not reuse any blocks which are
1235 * allocated in the bitmap buffer's "last committed data" copy.  This
1236 * prevents deletes from freeing up the page for reuse until we have
1237 * committed the delete transaction.
1238 *
1239 * If we didn't do this, then deleting something and reallocating it as
1240 * data would allow the old block to be overwritten before the
1241 * transaction committed (because we force data to disk before commit).
1242 * This would lead to corruption if we crashed between overwriting the
1243 * data and committing the delete.
1244 *
1245 * @@@ We may want to make this allocation behaviour conditional on
1246 * data-writes at some point, and disable it for metadata allocations or
1247 * sync-data inodes."
1248 *
1249 * Note: OCFS2 already does this differently for metadata vs data
1250 * allocations, as those bitmaps are separate and undo access is never
1251 * called on a metadata group descriptor.
1252 */
1253static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
1254					 int nr)
1255{
1256	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1257	struct journal_head *jh;
1258	int ret;
1259
1260	if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
1261		return 0;
1262
1263	jh = jbd2_journal_grab_journal_head(bg_bh);
1264	if (!jh)
1265		return 1;
1266
1267	spin_lock(&jh->b_state_lock);
1268	bg = (struct ocfs2_group_desc *) jh->b_committed_data;
1269	if (bg)
1270		ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
1271	else
1272		ret = 1;
1273	spin_unlock(&jh->b_state_lock);
1274	jbd2_journal_put_journal_head(jh);
1275
1276	return ret;
1277}
1278
1279u16 ocfs2_find_max_contig_free_bits(void *bitmap,
1280			 u16 total_bits, u16 start)
1281{
1282	u16 offset, free_bits;
1283	u16 contig_bits = 0;
1284
1285	while (start < total_bits) {
1286		offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start);
1287		if (offset == total_bits)
1288			break;
1289
1290		start = ocfs2_find_next_bit(bitmap, total_bits, offset);
1291		free_bits = start - offset;
1292		if (contig_bits < free_bits)
1293			contig_bits = free_bits;
1294	}
1295
1296	return contig_bits;
1297}
1298
1299static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
1300					     struct buffer_head *bg_bh,
1301					     unsigned int bits_wanted,
1302					     unsigned int total_bits,
1303					     struct ocfs2_suballoc_result *res)
1304{
1305	void *bitmap;
1306	u16 best_offset, best_size;
1307	u16 prev_best_size = 0;
1308	int offset, start, found, status = 0;
1309	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1310
1311	/* Callers got this descriptor from
1312	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1313	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1314
1315	found = start = best_offset = best_size = 0;
1316	bitmap = bg->bg_bitmap;
1317
1318	while ((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) <
1319	       total_bits) {
 
 
1320		if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
1321			/* We found a zero, but we can't use it as it
1322			 * hasn't been put to disk yet! */
1323			found = 0;
1324			start = offset + 1;
1325		} else if (offset == start) {
1326			/* we found a zero */
1327			found++;
1328			/* move start to the next bit to test */
1329			start++;
1330		} else {
1331			/* got a zero after some ones */
1332			found = 1;
1333			start = offset + 1;
1334			prev_best_size = best_size;
1335		}
1336		if (found > best_size) {
1337			best_size = found;
1338			best_offset = start - found;
1339		}
1340		/* we got everything we needed */
1341		if (found == bits_wanted) {
1342			/* mlog(0, "Found it all!\n"); */
1343			break;
1344		}
1345	}
1346
1347	/* best_size will be allocated, we save prev_best_size */
1348	res->sr_max_contig_bits = prev_best_size;
1349	if (best_size) {
1350		res->sr_bit_offset = best_offset;
1351		res->sr_bits = best_size;
1352	} else {
1353		status = -ENOSPC;
1354		/* No error log here -- see the comment above
1355		 * ocfs2_test_bg_bit_allocatable */
1356	}
1357
1358	return status;
1359}
1360
1361int ocfs2_block_group_set_bits(handle_t *handle,
1362					     struct inode *alloc_inode,
1363					     struct ocfs2_group_desc *bg,
1364					     struct buffer_head *group_bh,
1365					     unsigned int bit_off,
1366					     unsigned int num_bits,
1367					     unsigned int max_contig_bits,
1368					     int fastpath)
1369{
1370	int status;
1371	void *bitmap = bg->bg_bitmap;
1372	int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1373	unsigned int start = bit_off + num_bits;
1374	u16 contig_bits;
1375	struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
1376
1377	/* All callers get the descriptor via
1378	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1379	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1380	BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
1381
1382	trace_ocfs2_block_group_set_bits(bit_off, num_bits);
1383
1384	if (ocfs2_is_cluster_bitmap(alloc_inode))
1385		journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1386
1387	status = ocfs2_journal_access_gd(handle,
1388					 INODE_CACHE(alloc_inode),
1389					 group_bh,
1390					 journal_type);
1391	if (status < 0) {
1392		mlog_errno(status);
1393		goto bail;
1394	}
1395
1396	le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
1397	if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
1398		return ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit count %u but claims %u are freed. num_bits %d\n",
1399				   (unsigned long long)le64_to_cpu(bg->bg_blkno),
1400				   le16_to_cpu(bg->bg_bits),
1401				   le16_to_cpu(bg->bg_free_bits_count),
1402				   num_bits);
 
1403	}
1404	while(num_bits--)
1405		ocfs2_set_bit(bit_off++, bitmap);
1406
1407	/*
1408	 * this is optimize path, caller set old contig value
1409	 * in max_contig_bits to bypass finding action.
1410	 */
1411	if (fastpath) {
1412		bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits);
1413	} else if (ocfs2_is_cluster_bitmap(alloc_inode)) {
1414		/*
1415		 * Usually, the block group bitmap allocates only 1 bit
1416		 * at a time, while the cluster group allocates n bits
1417		 * each time. Therefore, we only save the contig bits for
1418		 * the cluster group.
1419		 */
1420		contig_bits = ocfs2_find_max_contig_free_bits(bitmap,
1421				    le16_to_cpu(bg->bg_bits), start);
1422		if (contig_bits > max_contig_bits)
1423			max_contig_bits = contig_bits;
1424		bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits);
1425		ocfs2_local_alloc_seen_free_bits(osb, max_contig_bits);
1426	} else {
1427		bg->bg_contig_free_bits = 0;
1428	}
1429
1430	ocfs2_journal_dirty(handle, group_bh);
1431
1432bail:
1433	return status;
1434}
1435
1436/* find the one with the most empty bits */
1437static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
1438{
1439	u16 curr, best;
1440
1441	BUG_ON(!cl->cl_next_free_rec);
1442
1443	best = curr = 0;
1444	while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
1445		if (le32_to_cpu(cl->cl_recs[curr].c_free) >
1446		    le32_to_cpu(cl->cl_recs[best].c_free))
1447			best = curr;
1448		curr++;
1449	}
1450
1451	BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
1452	return best;
1453}
1454
1455static int ocfs2_relink_block_group(handle_t *handle,
1456				    struct inode *alloc_inode,
1457				    struct buffer_head *fe_bh,
1458				    struct buffer_head *bg_bh,
1459				    struct buffer_head *prev_bg_bh,
1460				    u16 chain)
1461{
1462	int status;
1463	/* there is a really tiny chance the journal calls could fail,
1464	 * but we wouldn't want inconsistent blocks in *any* case. */
1465	u64 bg_ptr, prev_bg_ptr;
1466	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
1467	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1468	struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
1469
1470	/* The caller got these descriptors from
1471	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1472	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1473	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
1474
1475	trace_ocfs2_relink_block_group(
1476		(unsigned long long)le64_to_cpu(fe->i_blkno), chain,
1477		(unsigned long long)le64_to_cpu(bg->bg_blkno),
1478		(unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1479
1480	bg_ptr = le64_to_cpu(bg->bg_next_group);
1481	prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1482
1483	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1484					 prev_bg_bh,
1485					 OCFS2_JOURNAL_ACCESS_WRITE);
1486	if (status < 0)
1487		goto out;
1488
1489	prev_bg->bg_next_group = bg->bg_next_group;
1490	ocfs2_journal_dirty(handle, prev_bg_bh);
1491
1492	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1493					 bg_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1494	if (status < 0)
1495		goto out_rollback_prev_bg;
1496
1497	bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1498	ocfs2_journal_dirty(handle, bg_bh);
1499
1500	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
1501					 fe_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1502	if (status < 0)
1503		goto out_rollback_bg;
1504
1505	fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1506	ocfs2_journal_dirty(handle, fe_bh);
1507
1508out:
1509	if (status < 0)
1510		mlog_errno(status);
1511	return status;
1512
1513out_rollback_bg:
1514	bg->bg_next_group = cpu_to_le64(bg_ptr);
1515out_rollback_prev_bg:
1516	prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1517	goto out;
1518}
1519
1520static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1521						     u32 wanted)
1522{
1523	return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1524}
1525
1526/* return 0 on success, -ENOSPC to keep searching and any other < 0
1527 * value on error. */
1528static int ocfs2_cluster_group_search(struct inode *inode,
1529				      struct buffer_head *group_bh,
1530				      u32 bits_wanted, u32 min_bits,
1531				      u64 max_block,
1532				      struct ocfs2_suballoc_result *res)
1533{
1534	int search = -ENOSPC;
1535	int ret;
1536	u64 blkoff;
1537	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1538	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1539	unsigned int max_bits, gd_cluster_off;
1540
1541	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1542
1543	if (le16_to_cpu(gd->bg_contig_free_bits) &&
1544	    le16_to_cpu(gd->bg_contig_free_bits) < bits_wanted)
1545		return -ENOSPC;
1546
1547	/* ->bg_contig_free_bits may un-initialized, so compare again */
1548	if (le16_to_cpu(gd->bg_free_bits_count) >= bits_wanted) {
1549		max_bits = le16_to_cpu(gd->bg_bits);
1550
1551		/* Tail groups in cluster bitmaps which aren't cpg
1552		 * aligned are prone to partial extension by a failed
1553		 * fs resize. If the file system resize never got to
1554		 * update the dinode cluster count, then we don't want
1555		 * to trust any clusters past it, regardless of what
1556		 * the group descriptor says. */
1557		gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1558							  le64_to_cpu(gd->bg_blkno));
1559		if ((gd_cluster_off + max_bits) >
1560		    OCFS2_I(inode)->ip_clusters) {
1561			max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1562			trace_ocfs2_cluster_group_search_wrong_max_bits(
1563				(unsigned long long)le64_to_cpu(gd->bg_blkno),
1564				le16_to_cpu(gd->bg_bits),
1565				OCFS2_I(inode)->ip_clusters, max_bits);
1566		}
1567
1568		ret = ocfs2_block_group_find_clear_bits(osb,
1569							group_bh, bits_wanted,
1570							max_bits, res);
1571		if (ret)
1572			return ret;
1573
1574		if (max_block) {
1575			blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1576							  gd_cluster_off +
1577							  res->sr_bit_offset +
1578							  res->sr_bits);
1579			trace_ocfs2_cluster_group_search_max_block(
1580				(unsigned long long)blkoff,
1581				(unsigned long long)max_block);
1582			if (blkoff > max_block)
1583				return -ENOSPC;
1584		}
1585
1586		/* ocfs2_block_group_find_clear_bits() might
1587		 * return success, but we still want to return
1588		 * -ENOSPC unless it found the minimum number
1589		 * of bits. */
1590		if (min_bits <= res->sr_bits)
1591			search = 0; /* success */
 
 
 
 
 
 
 
1592	}
1593
1594	return search;
1595}
1596
1597static int ocfs2_block_group_search(struct inode *inode,
1598				    struct buffer_head *group_bh,
1599				    u32 bits_wanted, u32 min_bits,
1600				    u64 max_block,
1601				    struct ocfs2_suballoc_result *res)
1602{
1603	int ret = -ENOSPC;
1604	u64 blkoff;
1605	struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1606
1607	BUG_ON(min_bits != 1);
1608	BUG_ON(ocfs2_is_cluster_bitmap(inode));
1609
1610	if (le16_to_cpu(bg->bg_free_bits_count) >= bits_wanted) {
1611		ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1612							group_bh, bits_wanted,
1613							le16_to_cpu(bg->bg_bits),
1614							res);
1615		if (!ret && max_block) {
1616			blkoff = le64_to_cpu(bg->bg_blkno) +
1617				res->sr_bit_offset + res->sr_bits;
1618			trace_ocfs2_block_group_search_max_block(
1619				(unsigned long long)blkoff,
1620				(unsigned long long)max_block);
1621			if (blkoff > max_block)
1622				ret = -ENOSPC;
1623		}
1624	}
1625
1626	return ret;
1627}
1628
1629int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1630				       handle_t *handle,
1631				       struct buffer_head *di_bh,
1632				       u32 num_bits,
1633				       u16 chain)
1634{
1635	int ret;
1636	u32 tmp_used;
1637	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1638	struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1639
1640	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
1641				      OCFS2_JOURNAL_ACCESS_WRITE);
1642	if (ret < 0) {
1643		mlog_errno(ret);
1644		goto out;
1645	}
1646
1647	tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1648	di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1649	le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1650	ocfs2_journal_dirty(handle, di_bh);
1651
1652out:
1653	return ret;
1654}
1655
1656void ocfs2_rollback_alloc_dinode_counts(struct inode *inode,
1657				       struct buffer_head *di_bh,
1658				       u32 num_bits,
1659				       u16 chain)
1660{
1661	u32 tmp_used;
1662	struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1663	struct ocfs2_chain_list *cl;
1664
1665	cl = (struct ocfs2_chain_list *)&di->id2.i_chain;
1666	tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1667	di->id1.bitmap1.i_used = cpu_to_le32(tmp_used - num_bits);
1668	le32_add_cpu(&cl->cl_recs[chain].c_free, num_bits);
1669}
1670
1671static int ocfs2_bg_discontig_fix_by_rec(struct ocfs2_suballoc_result *res,
1672					 struct ocfs2_extent_rec *rec,
1673					 struct ocfs2_chain_list *cl)
1674{
1675	unsigned int bpc = le16_to_cpu(cl->cl_bpc);
1676	unsigned int bitoff = le32_to_cpu(rec->e_cpos) * bpc;
1677	unsigned int bitcount = le16_to_cpu(rec->e_leaf_clusters) * bpc;
1678
1679	if (res->sr_bit_offset < bitoff)
1680		return 0;
1681	if (res->sr_bit_offset >= (bitoff + bitcount))
1682		return 0;
1683	res->sr_blkno = le64_to_cpu(rec->e_blkno) +
1684		(res->sr_bit_offset - bitoff);
1685	if ((res->sr_bit_offset + res->sr_bits) > (bitoff + bitcount))
1686		res->sr_bits = (bitoff + bitcount) - res->sr_bit_offset;
1687	return 1;
1688}
1689
1690static void ocfs2_bg_discontig_fix_result(struct ocfs2_alloc_context *ac,
1691					  struct ocfs2_group_desc *bg,
1692					  struct ocfs2_suballoc_result *res)
1693{
1694	int i;
1695	u64 bg_blkno = res->sr_bg_blkno;  /* Save off */
1696	struct ocfs2_extent_rec *rec;
1697	struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1698	struct ocfs2_chain_list *cl = &di->id2.i_chain;
1699
1700	if (ocfs2_is_cluster_bitmap(ac->ac_inode)) {
1701		res->sr_blkno = 0;
1702		return;
1703	}
1704
1705	res->sr_blkno = res->sr_bg_blkno + res->sr_bit_offset;
1706	res->sr_bg_blkno = 0;  /* Clear it for contig block groups */
1707	if (!ocfs2_supports_discontig_bg(OCFS2_SB(ac->ac_inode->i_sb)) ||
1708	    !bg->bg_list.l_next_free_rec)
1709		return;
1710
1711	for (i = 0; i < le16_to_cpu(bg->bg_list.l_next_free_rec); i++) {
1712		rec = &bg->bg_list.l_recs[i];
1713		if (ocfs2_bg_discontig_fix_by_rec(res, rec, cl)) {
1714			res->sr_bg_blkno = bg_blkno;  /* Restore */
1715			break;
1716		}
1717	}
1718}
1719
1720static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1721				  handle_t *handle,
1722				  u32 bits_wanted,
1723				  u32 min_bits,
1724				  struct ocfs2_suballoc_result *res,
1725				  u16 *bits_left)
1726{
1727	int ret;
1728	struct buffer_head *group_bh = NULL;
1729	struct ocfs2_group_desc *gd;
1730	struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1731	struct inode *alloc_inode = ac->ac_inode;
1732
1733	ret = ocfs2_read_group_descriptor(alloc_inode, di,
1734					  res->sr_bg_blkno, &group_bh);
1735	if (ret < 0) {
1736		mlog_errno(ret);
1737		return ret;
1738	}
1739
1740	gd = (struct ocfs2_group_desc *) group_bh->b_data;
1741	ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1742				  ac->ac_max_block, res);
1743	if (ret < 0) {
1744		if (ret != -ENOSPC)
1745			mlog_errno(ret);
1746		goto out;
1747	}
1748
1749	if (!ret)
1750		ocfs2_bg_discontig_fix_result(ac, gd, res);
1751
1752	/*
1753	 * sr_bg_blkno might have been changed by
1754	 * ocfs2_bg_discontig_fix_result
1755	 */
1756	res->sr_bg_stable_blkno = group_bh->b_blocknr;
1757
1758	if (ac->ac_find_loc_only)
1759		goto out_loc_only;
1760
1761	ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1762					       res->sr_bits,
1763					       le16_to_cpu(gd->bg_chain));
1764	if (ret < 0) {
1765		mlog_errno(ret);
1766		goto out;
1767	}
1768
1769	ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1770					 res->sr_bit_offset, res->sr_bits,
1771					 res->sr_max_contig_bits, 0);
1772	if (ret < 0) {
1773		ocfs2_rollback_alloc_dinode_counts(alloc_inode, ac->ac_bh,
1774					       res->sr_bits,
1775					       le16_to_cpu(gd->bg_chain));
1776		mlog_errno(ret);
1777	}
1778
1779out_loc_only:
1780	*bits_left = le16_to_cpu(gd->bg_free_bits_count);
1781
1782out:
1783	brelse(group_bh);
1784
1785	return ret;
1786}
1787
1788static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1789			      handle_t *handle,
1790			      u32 bits_wanted,
1791			      u32 min_bits,
1792			      struct ocfs2_suballoc_result *res,
1793			      u16 *bits_left)
1794{
1795	int status;
1796	u16 chain;
1797	u64 next_group;
1798	struct inode *alloc_inode = ac->ac_inode;
1799	struct buffer_head *group_bh = NULL;
1800	struct buffer_head *prev_group_bh = NULL;
1801	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1802	struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1803	struct ocfs2_group_desc *bg;
1804
1805	chain = ac->ac_chain;
1806	trace_ocfs2_search_chain_begin(
1807		(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
1808		bits_wanted, chain);
1809
1810	status = ocfs2_read_group_descriptor(alloc_inode, fe,
1811					     le64_to_cpu(cl->cl_recs[chain].c_blkno),
1812					     &group_bh);
1813	if (status < 0) {
1814		mlog_errno(status);
1815		goto bail;
1816	}
1817	bg = (struct ocfs2_group_desc *) group_bh->b_data;
1818
1819	status = -ENOSPC;
1820	/* for now, the chain search is a bit simplistic. We just use
1821	 * the 1st group with any empty bits. */
1822	while ((status = ac->ac_group_search(alloc_inode, group_bh,
1823					     bits_wanted, min_bits,
1824					     ac->ac_max_block,
1825					     res)) == -ENOSPC) {
1826		if (!bg->bg_next_group)
1827			break;
1828
1829		brelse(prev_group_bh);
1830		prev_group_bh = NULL;
1831
1832		next_group = le64_to_cpu(bg->bg_next_group);
1833		prev_group_bh = group_bh;
1834		group_bh = NULL;
1835		status = ocfs2_read_group_descriptor(alloc_inode, fe,
1836						     next_group, &group_bh);
1837		if (status < 0) {
1838			mlog_errno(status);
1839			goto bail;
1840		}
1841		bg = (struct ocfs2_group_desc *) group_bh->b_data;
1842	}
1843	if (status < 0) {
1844		if (status != -ENOSPC)
1845			mlog_errno(status);
1846		goto bail;
1847	}
1848
1849	trace_ocfs2_search_chain_succ(
1850		(unsigned long long)le64_to_cpu(bg->bg_blkno), res->sr_bits);
1851
1852	res->sr_bg_blkno = le64_to_cpu(bg->bg_blkno);
1853
1854	BUG_ON(res->sr_bits == 0);
1855	if (!status)
1856		ocfs2_bg_discontig_fix_result(ac, bg, res);
1857
1858	/*
1859	 * sr_bg_blkno might have been changed by
1860	 * ocfs2_bg_discontig_fix_result
1861	 */
1862	res->sr_bg_stable_blkno = group_bh->b_blocknr;
1863
1864	/*
1865	 * Keep track of previous block descriptor read. When
1866	 * we find a target, if we have read more than X
1867	 * number of descriptors, and the target is reasonably
1868	 * empty, relink him to top of his chain.
1869	 *
1870	 * We've read 0 extra blocks and only send one more to
1871	 * the transaction, yet the next guy to search has a
1872	 * much easier time.
1873	 *
1874	 * Do this *after* figuring out how many bits we're taking out
1875	 * of our target group.
1876	 */
1877	if (!ac->ac_disable_chain_relink &&
1878	    (prev_group_bh) &&
1879	    (ocfs2_block_group_reasonably_empty(bg, res->sr_bits))) {
1880		status = ocfs2_relink_block_group(handle, alloc_inode,
1881						  ac->ac_bh, group_bh,
1882						  prev_group_bh, chain);
1883		if (status < 0) {
1884			mlog_errno(status);
1885			goto bail;
1886		}
1887	}
1888
1889	if (ac->ac_find_loc_only)
1890		goto out_loc_only;
1891
1892	status = ocfs2_alloc_dinode_update_counts(alloc_inode, handle,
1893						  ac->ac_bh, res->sr_bits,
1894						  chain);
1895	if (status) {
1896		mlog_errno(status);
1897		goto bail;
1898	}
1899
1900	status = ocfs2_block_group_set_bits(handle,
1901					    alloc_inode,
1902					    bg,
1903					    group_bh,
1904					    res->sr_bit_offset,
1905					    res->sr_bits,
1906					    res->sr_max_contig_bits,
1907					    0);
1908	if (status < 0) {
1909		ocfs2_rollback_alloc_dinode_counts(alloc_inode,
1910					ac->ac_bh, res->sr_bits, chain);
1911		mlog_errno(status);
1912		goto bail;
1913	}
1914
1915	trace_ocfs2_search_chain_end(
1916			(unsigned long long)le64_to_cpu(fe->i_blkno),
1917			res->sr_bits);
1918
1919out_loc_only:
1920	*bits_left = le16_to_cpu(bg->bg_free_bits_count);
1921bail:
1922	brelse(group_bh);
1923	brelse(prev_group_bh);
1924
1925	if (status)
1926		mlog_errno(status);
1927	return status;
1928}
1929
1930/* will give out up to bits_wanted contiguous bits. */
1931static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
1932				     handle_t *handle,
1933				     u32 bits_wanted,
1934				     u32 min_bits,
1935				     struct ocfs2_suballoc_result *res)
1936{
1937	int status;
1938	u16 victim, i;
1939	u16 bits_left = 0;
1940	u64 hint = ac->ac_last_group;
1941	struct ocfs2_chain_list *cl;
1942	struct ocfs2_dinode *fe;
1943
1944	BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1945	BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1946	BUG_ON(!ac->ac_bh);
1947
1948	fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1949
1950	/* The bh was validated by the inode read during
1951	 * ocfs2_reserve_suballoc_bits().  Any corruption is a code bug. */
1952	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1953
1954	if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1955	    le32_to_cpu(fe->id1.bitmap1.i_total)) {
1956		status = ocfs2_error(ac->ac_inode->i_sb,
1957				     "Chain allocator dinode %llu has %u used bits but only %u total\n",
1958				     (unsigned long long)le64_to_cpu(fe->i_blkno),
1959				     le32_to_cpu(fe->id1.bitmap1.i_used),
1960				     le32_to_cpu(fe->id1.bitmap1.i_total));
 
 
1961		goto bail;
1962	}
1963
1964	res->sr_bg_blkno = hint;
1965	if (res->sr_bg_blkno) {
1966		/* Attempt to short-circuit the usual search mechanism
1967		 * by jumping straight to the most recently used
1968		 * allocation group. This helps us maintain some
1969		 * contiguousness across allocations. */
1970		status = ocfs2_search_one_group(ac, handle, bits_wanted,
1971						min_bits, res, &bits_left);
1972		if (!status)
1973			goto set_hint;
1974		if (status < 0 && status != -ENOSPC) {
1975			mlog_errno(status);
1976			goto bail;
1977		}
1978	}
1979
1980	cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1981
1982	victim = ocfs2_find_victim_chain(cl);
1983	ac->ac_chain = victim;
1984
1985	status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1986				    res, &bits_left);
1987	if (!status) {
1988		if (ocfs2_is_cluster_bitmap(ac->ac_inode))
1989			hint = res->sr_bg_blkno;
1990		else
1991			hint = ocfs2_group_from_res(res);
1992		goto set_hint;
1993	}
1994	if (status < 0 && status != -ENOSPC) {
1995		mlog_errno(status);
1996		goto bail;
1997	}
1998
1999	trace_ocfs2_claim_suballoc_bits(victim);
2000
2001	/* If we didn't pick a good victim, then just default to
2002	 * searching each chain in order. Don't allow chain relinking
2003	 * because we only calculate enough journal credits for one
2004	 * relink per alloc. */
2005	ac->ac_disable_chain_relink = 1;
2006	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
2007		if (i == victim)
2008			continue;
2009		if (le32_to_cpu(cl->cl_recs[i].c_free) < bits_wanted)
2010			continue;
2011
2012		ac->ac_chain = i;
2013		status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
2014					    res, &bits_left);
2015		if (!status) {
2016			hint = ocfs2_group_from_res(res);
2017			break;
2018		}
2019		if (status < 0 && status != -ENOSPC) {
2020			mlog_errno(status);
2021			goto bail;
2022		}
2023	}
2024
2025set_hint:
2026	if (status != -ENOSPC) {
2027		/* If the next search of this group is not likely to
2028		 * yield a suitable extent, then we reset the last
2029		 * group hint so as to not waste a disk read */
2030		if (bits_left < min_bits)
2031			ac->ac_last_group = 0;
2032		else
2033			ac->ac_last_group = hint;
2034	}
2035
2036bail:
2037	if (status)
2038		mlog_errno(status);
2039	return status;
2040}
2041
2042int ocfs2_claim_metadata(handle_t *handle,
2043			 struct ocfs2_alloc_context *ac,
2044			 u32 bits_wanted,
2045			 u64 *suballoc_loc,
2046			 u16 *suballoc_bit_start,
2047			 unsigned int *num_bits,
2048			 u64 *blkno_start)
2049{
2050	int status;
2051	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2052
2053	BUG_ON(!ac);
2054	BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
2055	BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
2056
2057	status = ocfs2_claim_suballoc_bits(ac,
2058					   handle,
2059					   bits_wanted,
2060					   1,
2061					   &res);
2062	if (status < 0) {
2063		mlog_errno(status);
2064		goto bail;
2065	}
2066	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2067
2068	*suballoc_loc = res.sr_bg_blkno;
2069	*suballoc_bit_start = res.sr_bit_offset;
2070	*blkno_start = res.sr_blkno;
2071	ac->ac_bits_given += res.sr_bits;
2072	*num_bits = res.sr_bits;
2073	status = 0;
2074bail:
2075	if (status)
2076		mlog_errno(status);
2077	return status;
2078}
2079
2080static void ocfs2_init_inode_ac_group(struct inode *dir,
2081				      struct buffer_head *parent_di_bh,
2082				      struct ocfs2_alloc_context *ac)
2083{
2084	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_di_bh->b_data;
2085	/*
2086	 * Try to allocate inodes from some specific group.
2087	 *
2088	 * If the parent dir has recorded the last group used in allocation,
2089	 * cool, use it. Otherwise if we try to allocate new inode from the
2090	 * same slot the parent dir belongs to, use the same chunk.
2091	 *
2092	 * We are very careful here to avoid the mistake of setting
2093	 * ac_last_group to a group descriptor from a different (unlocked) slot.
2094	 */
2095	if (OCFS2_I(dir)->ip_last_used_group &&
2096	    OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
2097		ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
2098	else if (le16_to_cpu(di->i_suballoc_slot) == ac->ac_alloc_slot) {
2099		if (di->i_suballoc_loc)
2100			ac->ac_last_group = le64_to_cpu(di->i_suballoc_loc);
2101		else
2102			ac->ac_last_group = ocfs2_which_suballoc_group(
2103					le64_to_cpu(di->i_blkno),
2104					le16_to_cpu(di->i_suballoc_bit));
2105	}
2106}
2107
2108static inline void ocfs2_save_inode_ac_group(struct inode *dir,
2109					     struct ocfs2_alloc_context *ac)
2110{
2111	OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
2112	OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
2113}
2114
2115int ocfs2_find_new_inode_loc(struct inode *dir,
2116			     struct buffer_head *parent_fe_bh,
2117			     struct ocfs2_alloc_context *ac,
2118			     u64 *fe_blkno)
2119{
2120	int ret;
2121	handle_t *handle = NULL;
2122	struct ocfs2_suballoc_result *res;
2123
2124	BUG_ON(!ac);
2125	BUG_ON(ac->ac_bits_given != 0);
2126	BUG_ON(ac->ac_bits_wanted != 1);
2127	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2128
2129	res = kzalloc(sizeof(*res), GFP_NOFS);
2130	if (res == NULL) {
2131		ret = -ENOMEM;
2132		mlog_errno(ret);
2133		goto out;
2134	}
2135
2136	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2137
2138	/*
2139	 * The handle started here is for chain relink. Alternatively,
2140	 * we could just disable relink for these calls.
2141	 */
2142	handle = ocfs2_start_trans(OCFS2_SB(dir->i_sb), OCFS2_SUBALLOC_ALLOC);
2143	if (IS_ERR(handle)) {
2144		ret = PTR_ERR(handle);
2145		handle = NULL;
2146		mlog_errno(ret);
2147		goto out;
2148	}
2149
2150	/*
2151	 * This will instruct ocfs2_claim_suballoc_bits and
2152	 * ocfs2_search_one_group to search but save actual allocation
2153	 * for later.
2154	 */
2155	ac->ac_find_loc_only = 1;
2156
2157	ret = ocfs2_claim_suballoc_bits(ac, handle, 1, 1, res);
2158	if (ret < 0) {
2159		mlog_errno(ret);
2160		goto out;
2161	}
2162
2163	ac->ac_find_loc_priv = res;
2164	*fe_blkno = res->sr_blkno;
2165	ocfs2_update_inode_fsync_trans(handle, dir, 0);
2166out:
2167	if (handle)
2168		ocfs2_commit_trans(OCFS2_SB(dir->i_sb), handle);
2169
2170	if (ret)
2171		kfree(res);
2172
2173	return ret;
2174}
2175
2176int ocfs2_claim_new_inode_at_loc(handle_t *handle,
2177				 struct inode *dir,
2178				 struct ocfs2_alloc_context *ac,
2179				 u64 *suballoc_loc,
2180				 u16 *suballoc_bit,
2181				 u64 di_blkno)
2182{
2183	int ret;
2184	u16 chain;
2185	struct ocfs2_suballoc_result *res = ac->ac_find_loc_priv;
2186	struct buffer_head *bg_bh = NULL;
2187	struct ocfs2_group_desc *bg;
2188	struct ocfs2_dinode *di = (struct ocfs2_dinode *) ac->ac_bh->b_data;
2189
2190	/*
2191	 * Since di_blkno is being passed back in, we check for any
2192	 * inconsistencies which may have happened between
2193	 * calls. These are code bugs as di_blkno is not expected to
2194	 * change once returned from ocfs2_find_new_inode_loc()
2195	 */
2196	BUG_ON(res->sr_blkno != di_blkno);
2197
2198	ret = ocfs2_read_group_descriptor(ac->ac_inode, di,
2199					  res->sr_bg_stable_blkno, &bg_bh);
2200	if (ret) {
2201		mlog_errno(ret);
2202		goto out;
2203	}
2204
2205	bg = (struct ocfs2_group_desc *) bg_bh->b_data;
2206	chain = le16_to_cpu(bg->bg_chain);
2207
2208	ret = ocfs2_alloc_dinode_update_counts(ac->ac_inode, handle,
2209					       ac->ac_bh, res->sr_bits,
2210					       chain);
2211	if (ret) {
2212		mlog_errno(ret);
2213		goto out;
2214	}
2215
2216	ret = ocfs2_block_group_set_bits(handle,
2217					 ac->ac_inode,
2218					 bg,
2219					 bg_bh,
2220					 res->sr_bit_offset,
2221					 res->sr_bits,
2222					 res->sr_max_contig_bits,
2223					 0);
2224	if (ret < 0) {
2225		ocfs2_rollback_alloc_dinode_counts(ac->ac_inode,
2226					       ac->ac_bh, res->sr_bits, chain);
2227		mlog_errno(ret);
2228		goto out;
2229	}
2230
2231	trace_ocfs2_claim_new_inode_at_loc((unsigned long long)di_blkno,
2232					   res->sr_bits);
2233
2234	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2235
2236	BUG_ON(res->sr_bits != 1);
2237
2238	*suballoc_loc = res->sr_bg_blkno;
2239	*suballoc_bit = res->sr_bit_offset;
2240	ac->ac_bits_given++;
2241	ocfs2_save_inode_ac_group(dir, ac);
2242
2243out:
2244	brelse(bg_bh);
2245
2246	return ret;
2247}
2248
2249int ocfs2_claim_new_inode(handle_t *handle,
2250			  struct inode *dir,
2251			  struct buffer_head *parent_fe_bh,
2252			  struct ocfs2_alloc_context *ac,
2253			  u64 *suballoc_loc,
2254			  u16 *suballoc_bit,
2255			  u64 *fe_blkno)
2256{
2257	int status;
2258	struct ocfs2_suballoc_result res;
2259
2260	BUG_ON(!ac);
2261	BUG_ON(ac->ac_bits_given != 0);
2262	BUG_ON(ac->ac_bits_wanted != 1);
2263	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2264
2265	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2266
2267	status = ocfs2_claim_suballoc_bits(ac,
2268					   handle,
2269					   1,
2270					   1,
2271					   &res);
2272	if (status < 0) {
2273		mlog_errno(status);
2274		goto bail;
2275	}
2276	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2277
2278	BUG_ON(res.sr_bits != 1);
2279
2280	*suballoc_loc = res.sr_bg_blkno;
2281	*suballoc_bit = res.sr_bit_offset;
2282	*fe_blkno = res.sr_blkno;
2283	ac->ac_bits_given++;
2284	ocfs2_save_inode_ac_group(dir, ac);
2285	status = 0;
2286bail:
2287	if (status)
2288		mlog_errno(status);
2289	return status;
2290}
2291
2292/* translate a group desc. blkno and it's bitmap offset into
2293 * disk cluster offset. */
2294static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
2295						   u64 bg_blkno,
2296						   u16 bg_bit_off)
2297{
2298	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2299	u32 cluster = 0;
2300
2301	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2302
2303	if (bg_blkno != osb->first_cluster_group_blkno)
2304		cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
2305	cluster += (u32) bg_bit_off;
2306	return cluster;
2307}
2308
2309/* given a cluster offset, calculate which block group it belongs to
2310 * and return that block offset. */
2311u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
2312{
2313	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2314	u32 group_no;
2315
2316	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2317
2318	group_no = cluster / osb->bitmap_cpg;
2319	if (!group_no)
2320		return osb->first_cluster_group_blkno;
2321	return ocfs2_clusters_to_blocks(inode->i_sb,
2322					group_no * osb->bitmap_cpg);
2323}
2324
2325/* given the block number of a cluster start, calculate which cluster
2326 * group and descriptor bitmap offset that corresponds to. */
2327static inline void ocfs2_block_to_cluster_group(struct inode *inode,
2328						u64 data_blkno,
2329						u64 *bg_blkno,
2330						u16 *bg_bit_off)
2331{
2332	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2333	u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
2334
2335	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2336
2337	*bg_blkno = ocfs2_which_cluster_group(inode,
2338					      data_cluster);
2339
2340	if (*bg_blkno == osb->first_cluster_group_blkno)
2341		*bg_bit_off = (u16) data_cluster;
2342	else
2343		*bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
2344							     data_blkno - *bg_blkno);
2345}
2346
2347/*
2348 * min_bits - minimum contiguous chunk from this total allocation we
2349 * can handle. set to what we asked for originally for a full
2350 * contig. allocation, set to '1' to indicate we can deal with extents
2351 * of any size.
2352 */
2353int __ocfs2_claim_clusters(handle_t *handle,
2354			   struct ocfs2_alloc_context *ac,
2355			   u32 min_clusters,
2356			   u32 max_clusters,
2357			   u32 *cluster_start,
2358			   u32 *num_clusters)
2359{
2360	int status;
2361	unsigned int bits_wanted = max_clusters;
2362	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2363	struct ocfs2_super *osb = OCFS2_SB(ac->ac_inode->i_sb);
2364
2365	BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
2366
2367	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
2368	       && ac->ac_which != OCFS2_AC_USE_MAIN);
2369
2370	if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
2371		WARN_ON(min_clusters > 1);
2372
2373		status = ocfs2_claim_local_alloc_bits(osb,
2374						      handle,
2375						      ac,
2376						      bits_wanted,
2377						      cluster_start,
2378						      num_clusters);
2379		if (!status)
2380			atomic_inc(&osb->alloc_stats.local_data);
2381	} else {
2382		if (min_clusters > (osb->bitmap_cpg - 1)) {
2383			/* The only paths asking for contiguousness
2384			 * should know about this already. */
2385			mlog(ML_ERROR, "minimum allocation requested %u exceeds "
2386			     "group bitmap size %u!\n", min_clusters,
2387			     osb->bitmap_cpg);
2388			status = -ENOSPC;
2389			goto bail;
2390		}
2391		/* clamp the current request down to a realistic size. */
2392		if (bits_wanted > (osb->bitmap_cpg - 1))
2393			bits_wanted = osb->bitmap_cpg - 1;
2394
2395		status = ocfs2_claim_suballoc_bits(ac,
2396						   handle,
2397						   bits_wanted,
2398						   min_clusters,
2399						   &res);
2400		if (!status) {
2401			BUG_ON(res.sr_blkno); /* cluster alloc can't set */
2402			*cluster_start =
2403				ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
2404								 res.sr_bg_blkno,
2405								 res.sr_bit_offset);
2406			atomic_inc(&osb->alloc_stats.bitmap_data);
2407			*num_clusters = res.sr_bits;
2408		}
2409	}
2410	if (status < 0) {
2411		if (status != -ENOSPC)
2412			mlog_errno(status);
2413		goto bail;
2414	}
2415
2416	ac->ac_bits_given += *num_clusters;
2417
2418bail:
2419	if (status)
2420		mlog_errno(status);
2421	return status;
2422}
2423
2424int ocfs2_claim_clusters(handle_t *handle,
2425			 struct ocfs2_alloc_context *ac,
2426			 u32 min_clusters,
2427			 u32 *cluster_start,
2428			 u32 *num_clusters)
2429{
2430	unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
2431
2432	return __ocfs2_claim_clusters(handle, ac, min_clusters,
2433				      bits_wanted, cluster_start, num_clusters);
2434}
2435
2436static int ocfs2_block_group_clear_bits(handle_t *handle,
2437					struct inode *alloc_inode,
2438					struct ocfs2_group_desc *bg,
2439					struct buffer_head *group_bh,
2440					unsigned int bit_off,
2441					unsigned int num_bits,
2442					unsigned int max_contig_bits,
2443					void (*undo_fn)(unsigned int bit,
2444							unsigned long *bmap))
2445{
2446	int status;
2447	unsigned int tmp;
2448	u16 contig_bits;
2449	struct ocfs2_group_desc *undo_bg = NULL;
2450	struct journal_head *jh;
2451
2452	/* The caller got this descriptor from
2453	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
2454	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
2455
2456	trace_ocfs2_block_group_clear_bits(bit_off, num_bits);
2457
2458	BUG_ON(undo_fn && !ocfs2_is_cluster_bitmap(alloc_inode));
2459	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
2460					 group_bh,
2461					 undo_fn ?
2462					 OCFS2_JOURNAL_ACCESS_UNDO :
2463					 OCFS2_JOURNAL_ACCESS_WRITE);
2464	if (status < 0) {
2465		mlog_errno(status);
2466		goto bail;
2467	}
2468
2469	jh = bh2jh(group_bh);
2470	if (undo_fn) {
2471		spin_lock(&jh->b_state_lock);
2472		undo_bg = (struct ocfs2_group_desc *) jh->b_committed_data;
 
2473		BUG_ON(!undo_bg);
2474	}
2475
2476	tmp = num_bits;
2477	while(tmp--) {
2478		ocfs2_clear_bit((bit_off + tmp),
2479				(unsigned long *) bg->bg_bitmap);
2480		if (undo_fn)
2481			undo_fn(bit_off + tmp,
2482				(unsigned long *) undo_bg->bg_bitmap);
2483	}
2484	le16_add_cpu(&bg->bg_free_bits_count, num_bits);
2485	if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
2486		if (undo_fn)
2487			spin_unlock(&jh->b_state_lock);
2488		return ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit count %u but claims %u are freed. num_bits %d\n",
2489				   (unsigned long long)le64_to_cpu(bg->bg_blkno),
2490				   le16_to_cpu(bg->bg_bits),
2491				   le16_to_cpu(bg->bg_free_bits_count),
2492				   num_bits);
2493	}
2494
2495	/*
2496	 * TODO: even 'num_bits == 1' (the worst case, release 1 cluster),
2497	 * we still need to rescan whole bitmap.
2498	 */
2499	if (ocfs2_is_cluster_bitmap(alloc_inode)) {
2500		contig_bits = ocfs2_find_max_contig_free_bits(bg->bg_bitmap,
2501				    le16_to_cpu(bg->bg_bits), 0);
2502		if (contig_bits > max_contig_bits)
2503			max_contig_bits = contig_bits;
2504		bg->bg_contig_free_bits = cpu_to_le16(max_contig_bits);
2505	} else {
2506		bg->bg_contig_free_bits = 0;
2507	}
2508
2509	if (undo_fn)
2510		spin_unlock(&jh->b_state_lock);
2511
2512	ocfs2_journal_dirty(handle, group_bh);
2513bail:
2514	return status;
2515}
2516
2517/*
2518 * expects the suballoc inode to already be locked.
2519 */
2520static int _ocfs2_free_suballoc_bits(handle_t *handle,
2521				     struct inode *alloc_inode,
2522				     struct buffer_head *alloc_bh,
2523				     unsigned int start_bit,
2524				     u64 bg_blkno,
2525				     unsigned int count,
2526				     void (*undo_fn)(unsigned int bit,
2527						     unsigned long *bitmap))
2528{
2529	int status = 0;
2530	u32 tmp_used;
2531	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
2532	struct ocfs2_chain_list *cl = &fe->id2.i_chain;
2533	struct buffer_head *group_bh = NULL;
2534	struct ocfs2_group_desc *group;
2535	__le16 old_bg_contig_free_bits = 0;
2536
2537	/* The alloc_bh comes from ocfs2_free_dinode() or
2538	 * ocfs2_free_clusters().  The callers have all locked the
2539	 * allocator and gotten alloc_bh from the lock call.  This
2540	 * validates the dinode buffer.  Any corruption that has happened
2541	 * is a code bug. */
2542	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
2543	BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
2544
2545	trace_ocfs2_free_suballoc_bits(
2546		(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
2547		(unsigned long long)bg_blkno,
2548		start_bit, count);
2549
2550	status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
2551					     &group_bh);
2552	if (status < 0) {
2553		mlog_errno(status);
2554		goto bail;
2555	}
2556	group = (struct ocfs2_group_desc *) group_bh->b_data;
2557
2558	BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
2559
2560	if (ocfs2_is_cluster_bitmap(alloc_inode))
2561		old_bg_contig_free_bits = group->bg_contig_free_bits;
2562	status = ocfs2_block_group_clear_bits(handle, alloc_inode,
2563					      group, group_bh,
2564					      start_bit, count, 0, undo_fn);
2565	if (status < 0) {
2566		mlog_errno(status);
2567		goto bail;
2568	}
2569
2570	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
2571					 alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
2572	if (status < 0) {
2573		mlog_errno(status);
2574		ocfs2_block_group_set_bits(handle, alloc_inode, group, group_bh,
2575				start_bit, count,
2576				le16_to_cpu(old_bg_contig_free_bits), 1);
2577		goto bail;
2578	}
2579
2580	le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2581		     count);
2582	tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2583	fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2584	ocfs2_journal_dirty(handle, alloc_bh);
2585
2586bail:
2587	brelse(group_bh);
 
 
 
2588	return status;
2589}
2590
2591int ocfs2_free_suballoc_bits(handle_t *handle,
2592			     struct inode *alloc_inode,
2593			     struct buffer_head *alloc_bh,
2594			     unsigned int start_bit,
2595			     u64 bg_blkno,
2596			     unsigned int count)
2597{
2598	return _ocfs2_free_suballoc_bits(handle, alloc_inode, alloc_bh,
2599					 start_bit, bg_blkno, count, NULL);
2600}
2601
2602int ocfs2_free_dinode(handle_t *handle,
2603		      struct inode *inode_alloc_inode,
2604		      struct buffer_head *inode_alloc_bh,
2605		      struct ocfs2_dinode *di)
2606{
2607	u64 blk = le64_to_cpu(di->i_blkno);
2608	u16 bit = le16_to_cpu(di->i_suballoc_bit);
2609	u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2610
2611	if (di->i_suballoc_loc)
2612		bg_blkno = le64_to_cpu(di->i_suballoc_loc);
2613	return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2614					inode_alloc_bh, bit, bg_blkno, 1);
2615}
2616
2617static int _ocfs2_free_clusters(handle_t *handle,
2618				struct inode *bitmap_inode,
2619				struct buffer_head *bitmap_bh,
2620				u64 start_blk,
2621				unsigned int num_clusters,
2622				void (*undo_fn)(unsigned int bit,
2623						unsigned long *bitmap))
2624{
2625	int status;
2626	u16 bg_start_bit;
2627	u64 bg_blkno;
 
2628
2629	/* You can't ever have a contiguous set of clusters
2630	 * bigger than a block group bitmap so we never have to worry
2631	 * about looping on them.
2632	 * This is expensive. We can safely remove once this stuff has
2633	 * gotten tested really well. */
2634	BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb,
2635				ocfs2_blocks_to_clusters(bitmap_inode->i_sb,
2636							 start_blk)));
2637
 
2638
2639	ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2640				     &bg_start_bit);
2641
2642	trace_ocfs2_free_clusters((unsigned long long)bg_blkno,
2643			(unsigned long long)start_blk,
2644			bg_start_bit, num_clusters);
2645
2646	status = _ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2647					   bg_start_bit, bg_blkno,
2648					   num_clusters, undo_fn);
2649	if (status < 0) {
2650		mlog_errno(status);
2651		goto out;
2652	}
2653
2654	ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2655					 num_clusters);
2656
2657out:
 
 
2658	return status;
2659}
2660
2661int ocfs2_free_clusters(handle_t *handle,
2662			struct inode *bitmap_inode,
2663			struct buffer_head *bitmap_bh,
2664			u64 start_blk,
2665			unsigned int num_clusters)
2666{
2667	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2668				    start_blk, num_clusters,
2669				    _ocfs2_set_bit);
2670}
2671
2672/*
2673 * Give never-used clusters back to the global bitmap.  We don't need
2674 * to protect these bits in the undo buffer.
2675 */
2676int ocfs2_release_clusters(handle_t *handle,
2677			   struct inode *bitmap_inode,
2678			   struct buffer_head *bitmap_bh,
2679			   u64 start_blk,
2680			   unsigned int num_clusters)
2681{
2682	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2683				    start_blk, num_clusters,
2684				    _ocfs2_clear_bit);
2685}
2686
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2687/*
2688 * For a given allocation, determine which allocators will need to be
2689 * accessed, and lock them, reserving the appropriate number of bits.
2690 *
2691 * Sparse file systems call this from ocfs2_write_begin_nolock()
2692 * and ocfs2_allocate_unwritten_extents().
2693 *
2694 * File systems which don't support holes call this from
2695 * ocfs2_extend_allocation().
2696 */
2697int ocfs2_lock_allocators(struct inode *inode,
2698			  struct ocfs2_extent_tree *et,
2699			  u32 clusters_to_add, u32 extents_to_split,
2700			  struct ocfs2_alloc_context **data_ac,
2701			  struct ocfs2_alloc_context **meta_ac)
2702{
2703	int ret = 0, num_free_extents;
2704	unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2705	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2706
2707	*meta_ac = NULL;
2708	if (data_ac)
2709		*data_ac = NULL;
2710
2711	BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2712
2713	num_free_extents = ocfs2_num_free_extents(et);
2714	if (num_free_extents < 0) {
2715		ret = num_free_extents;
2716		mlog_errno(ret);
2717		goto out;
2718	}
2719
2720	/*
2721	 * Sparse allocation file systems need to be more conservative
2722	 * with reserving room for expansion - the actual allocation
2723	 * happens while we've got a journal handle open so re-taking
2724	 * a cluster lock (because we ran out of room for another
2725	 * extent) will violate ordering rules.
2726	 *
2727	 * Most of the time we'll only be seeing this 1 cluster at a time
2728	 * anyway.
2729	 *
2730	 * Always lock for any unwritten extents - we might want to
2731	 * add blocks during a split.
2732	 */
2733	if (!num_free_extents ||
2734	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2735		ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2736		if (ret < 0) {
2737			if (ret != -ENOSPC)
2738				mlog_errno(ret);
2739			goto out;
2740		}
2741	}
2742
2743	if (clusters_to_add == 0)
2744		goto out;
2745
2746	ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2747	if (ret < 0) {
2748		if (ret != -ENOSPC)
2749			mlog_errno(ret);
2750		goto out;
2751	}
2752
2753out:
2754	if (ret) {
2755		if (*meta_ac) {
2756			ocfs2_free_alloc_context(*meta_ac);
2757			*meta_ac = NULL;
2758		}
2759
2760		/*
2761		 * We cannot have an error and a non null *data_ac.
2762		 */
2763	}
2764
2765	return ret;
2766}
2767
2768/*
2769 * Read the inode specified by blkno to get suballoc_slot and
2770 * suballoc_bit.
2771 */
2772static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2773				       u16 *suballoc_slot, u64 *group_blkno,
2774				       u16 *suballoc_bit)
2775{
2776	int status;
2777	struct buffer_head *inode_bh = NULL;
2778	struct ocfs2_dinode *inode_fe;
2779
2780	trace_ocfs2_get_suballoc_slot_bit((unsigned long long)blkno);
2781
2782	/* dirty read disk */
2783	status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2784	if (status < 0) {
2785		mlog(ML_ERROR, "read block %llu failed %d\n",
2786		     (unsigned long long)blkno, status);
2787		goto bail;
2788	}
2789
2790	inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2791	if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2792		mlog(ML_ERROR, "invalid inode %llu requested\n",
2793		     (unsigned long long)blkno);
2794		status = -EINVAL;
2795		goto bail;
2796	}
2797
2798	if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2799	    (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2800		mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2801		     (unsigned long long)blkno,
2802		     (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2803		status = -EINVAL;
2804		goto bail;
2805	}
2806
2807	if (suballoc_slot)
2808		*suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2809	if (suballoc_bit)
2810		*suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2811	if (group_blkno)
2812		*group_blkno = le64_to_cpu(inode_fe->i_suballoc_loc);
2813
2814bail:
2815	brelse(inode_bh);
2816
2817	if (status)
2818		mlog_errno(status);
2819	return status;
2820}
2821
2822/*
2823 * test whether bit is SET in allocator bitmap or not.  on success, 0
2824 * is returned and *res is 1 for SET; 0 otherwise.  when fails, errno
2825 * is returned and *res is meaningless.  Call this after you have
2826 * cluster locked against suballoc, or you may get a result based on
2827 * non-up2date contents
2828 */
2829static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2830				   struct inode *suballoc,
2831				   struct buffer_head *alloc_bh,
2832				   u64 group_blkno, u64 blkno,
2833				   u16 bit, int *res)
2834{
2835	struct ocfs2_dinode *alloc_di;
2836	struct ocfs2_group_desc *group;
2837	struct buffer_head *group_bh = NULL;
2838	u64 bg_blkno;
2839	int status;
2840
2841	trace_ocfs2_test_suballoc_bit((unsigned long long)blkno,
2842				      (unsigned int)bit);
2843
2844	alloc_di = (struct ocfs2_dinode *)alloc_bh->b_data;
2845	if ((bit + 1) > ocfs2_bits_per_group(&alloc_di->id2.i_chain)) {
2846		mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2847		     (unsigned int)bit,
2848		     ocfs2_bits_per_group(&alloc_di->id2.i_chain));
2849		status = -EINVAL;
2850		goto bail;
2851	}
2852
2853	bg_blkno = group_blkno ? group_blkno :
2854		   ocfs2_which_suballoc_group(blkno, bit);
2855	status = ocfs2_read_group_descriptor(suballoc, alloc_di, bg_blkno,
2856					     &group_bh);
2857	if (status < 0) {
2858		mlog(ML_ERROR, "read group %llu failed %d\n",
2859		     (unsigned long long)bg_blkno, status);
2860		goto bail;
2861	}
2862
2863	group = (struct ocfs2_group_desc *) group_bh->b_data;
2864	*res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2865
2866bail:
2867	brelse(group_bh);
2868
2869	if (status)
2870		mlog_errno(status);
2871	return status;
2872}
2873
2874/*
2875 * Test if the bit representing this inode (blkno) is set in the
2876 * suballocator.
2877 *
2878 * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2879 *
2880 * In the event of failure, a negative value is returned and *res is
2881 * meaningless.
2882 *
2883 * Callers must make sure to hold nfs_sync_lock to prevent
2884 * ocfs2_delete_inode() on another node from accessing the same
2885 * suballocator concurrently.
2886 */
2887int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2888{
2889	int status;
2890	u64 group_blkno = 0;
2891	u16 suballoc_bit = 0, suballoc_slot = 0;
2892	struct inode *inode_alloc_inode;
2893	struct buffer_head *alloc_bh = NULL;
2894
2895	trace_ocfs2_test_inode_bit((unsigned long long)blkno);
2896
2897	status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2898					     &group_blkno, &suballoc_bit);
2899	if (status < 0) {
2900		mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2901		goto bail;
2902	}
2903
2904	if (suballoc_slot == (u16)OCFS2_INVALID_SLOT)
2905		inode_alloc_inode = ocfs2_get_system_file_inode(osb,
2906			GLOBAL_INODE_ALLOC_SYSTEM_INODE, suballoc_slot);
2907	else
2908		inode_alloc_inode = ocfs2_get_system_file_inode(osb,
2909			INODE_ALLOC_SYSTEM_INODE, suballoc_slot);
2910	if (!inode_alloc_inode) {
2911		/* the error code could be inaccurate, but we are not able to
2912		 * get the correct one. */
2913		status = -EINVAL;
2914		mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2915		     (u32)suballoc_slot);
2916		goto bail;
2917	}
2918
2919	inode_lock(inode_alloc_inode);
2920	status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2921	if (status < 0) {
2922		inode_unlock(inode_alloc_inode);
2923		iput(inode_alloc_inode);
2924		mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2925		     (u32)suballoc_slot, status);
2926		goto bail;
2927	}
2928
2929	status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2930					 group_blkno, blkno, suballoc_bit, res);
2931	if (status < 0)
2932		mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2933
2934	ocfs2_inode_unlock(inode_alloc_inode, 0);
2935	inode_unlock(inode_alloc_inode);
2936
2937	iput(inode_alloc_inode);
2938	brelse(alloc_bh);
2939bail:
2940	if (status)
2941		mlog_errno(status);
2942	return status;
2943}