1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
 
   3 * alloc.c
   4 *
   5 * Extent allocs and frees
   6 *
   7 * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   8 */
   9
  10#include <linux/fs.h>
  11#include <linux/types.h>
  12#include <linux/slab.h>
  13#include <linux/highmem.h>
  14#include <linux/swap.h>
  15#include <linux/quotaops.h>
  16#include <linux/blkdev.h>
  17#include <linux/sched/signal.h>
  18
  19#include <cluster/masklog.h>
  20
  21#include "ocfs2.h"
  22
  23#include "alloc.h"
  24#include "aops.h"
  25#include "blockcheck.h"
  26#include "dlmglue.h"
  27#include "extent_map.h"
  28#include "inode.h"
  29#include "journal.h"
  30#include "localalloc.h"
  31#include "suballoc.h"
  32#include "sysfile.h"
  33#include "file.h"
  34#include "super.h"
  35#include "uptodate.h"
  36#include "xattr.h"
  37#include "refcounttree.h"
  38#include "ocfs2_trace.h"
  39
  40#include "buffer_head_io.h"
  41
  42enum ocfs2_contig_type {
  43	CONTIG_NONE = 0,
  44	CONTIG_LEFT,
  45	CONTIG_RIGHT,
  46	CONTIG_LEFTRIGHT,
  47};
  48
  49static enum ocfs2_contig_type
  50	ocfs2_extent_rec_contig(struct super_block *sb,
  51				struct ocfs2_extent_rec *ext,
  52				struct ocfs2_extent_rec *insert_rec);
  53/*
  54 * Operations for a specific extent tree type.
  55 *
  56 * To implement an on-disk btree (extent tree) type in ocfs2, add
  57 * an ocfs2_extent_tree_operations structure and the matching
  58 * ocfs2_init_<thingy>_extent_tree() function.  That's pretty much it
  59 * for the allocation portion of the extent tree.
  60 */
  61struct ocfs2_extent_tree_operations {
  62	/*
  63	 * last_eb_blk is the block number of the right most leaf extent
  64	 * block.  Most on-disk structures containing an extent tree store
  65	 * this value for fast access.  The ->eo_set_last_eb_blk() and
  66	 * ->eo_get_last_eb_blk() operations access this value.  They are
  67	 *  both required.
  68	 */
  69	void (*eo_set_last_eb_blk)(struct ocfs2_extent_tree *et,
  70				   u64 blkno);
  71	u64 (*eo_get_last_eb_blk)(struct ocfs2_extent_tree *et);
  72
  73	/*
  74	 * The on-disk structure usually keeps track of how many total
  75	 * clusters are stored in this extent tree.  This function updates
  76	 * that value.  new_clusters is the delta, and must be
  77	 * added to the total.  Required.
  78	 */
  79	void (*eo_update_clusters)(struct ocfs2_extent_tree *et,
  80				   u32 new_clusters);
  81
  82	/*
  83	 * If this extent tree is supported by an extent map, insert
  84	 * a record into the map.
  85	 */
  86	void (*eo_extent_map_insert)(struct ocfs2_extent_tree *et,
  87				     struct ocfs2_extent_rec *rec);
  88
  89	/*
  90	 * If this extent tree is supported by an extent map, truncate the
  91	 * map to clusters,
  92	 */
  93	void (*eo_extent_map_truncate)(struct ocfs2_extent_tree *et,
  94				       u32 clusters);
  95
  96	/*
  97	 * If ->eo_insert_check() exists, it is called before rec is
  98	 * inserted into the extent tree.  It is optional.
  99	 */
 100	int (*eo_insert_check)(struct ocfs2_extent_tree *et,
 101			       struct ocfs2_extent_rec *rec);
 102	int (*eo_sanity_check)(struct ocfs2_extent_tree *et);
 103
 104	/*
 105	 * --------------------------------------------------------------
 106	 * The remaining are internal to ocfs2_extent_tree and don't have
 107	 * accessor functions
 108	 */
 109
 110	/*
 111	 * ->eo_fill_root_el() takes et->et_object and sets et->et_root_el.
 112	 * It is required.
 113	 */
 114	void (*eo_fill_root_el)(struct ocfs2_extent_tree *et);
 115
 116	/*
 117	 * ->eo_fill_max_leaf_clusters sets et->et_max_leaf_clusters if
 118	 * it exists.  If it does not, et->et_max_leaf_clusters is set
 119	 * to 0 (unlimited).  Optional.
 120	 */
 121	void (*eo_fill_max_leaf_clusters)(struct ocfs2_extent_tree *et);
 122
 123	/*
 124	 * ->eo_extent_contig test whether the 2 ocfs2_extent_rec
 125	 * are contiguous or not. Optional. Don't need to set it if use
 126	 * ocfs2_extent_rec as the tree leaf.
 127	 */
 128	enum ocfs2_contig_type
 129		(*eo_extent_contig)(struct ocfs2_extent_tree *et,
 130				    struct ocfs2_extent_rec *ext,
 131				    struct ocfs2_extent_rec *insert_rec);
 132};
 133
 134
 135/*
 136 * Pre-declare ocfs2_dinode_et_ops so we can use it as a sanity check
 137 * in the methods.
 138 */
 139static u64 ocfs2_dinode_get_last_eb_blk(struct ocfs2_extent_tree *et);
 140static void ocfs2_dinode_set_last_eb_blk(struct ocfs2_extent_tree *et,
 141					 u64 blkno);
 142static void ocfs2_dinode_update_clusters(struct ocfs2_extent_tree *et,
 143					 u32 clusters);
 144static void ocfs2_dinode_extent_map_insert(struct ocfs2_extent_tree *et,
 145					   struct ocfs2_extent_rec *rec);
 146static void ocfs2_dinode_extent_map_truncate(struct ocfs2_extent_tree *et,
 147					     u32 clusters);
 148static int ocfs2_dinode_insert_check(struct ocfs2_extent_tree *et,
 149				     struct ocfs2_extent_rec *rec);
 150static int ocfs2_dinode_sanity_check(struct ocfs2_extent_tree *et);
 151static void ocfs2_dinode_fill_root_el(struct ocfs2_extent_tree *et);
 152
 153static int ocfs2_reuse_blk_from_dealloc(handle_t *handle,
 154					struct ocfs2_extent_tree *et,
 155					struct buffer_head **new_eb_bh,
 156					int blk_wanted, int *blk_given);
 157static int ocfs2_is_dealloc_empty(struct ocfs2_extent_tree *et);
 158
 159static const struct ocfs2_extent_tree_operations ocfs2_dinode_et_ops = {
 160	.eo_set_last_eb_blk	= ocfs2_dinode_set_last_eb_blk,
 161	.eo_get_last_eb_blk	= ocfs2_dinode_get_last_eb_blk,
 162	.eo_update_clusters	= ocfs2_dinode_update_clusters,
 163	.eo_extent_map_insert	= ocfs2_dinode_extent_map_insert,
 164	.eo_extent_map_truncate	= ocfs2_dinode_extent_map_truncate,
 165	.eo_insert_check	= ocfs2_dinode_insert_check,
 166	.eo_sanity_check	= ocfs2_dinode_sanity_check,
 167	.eo_fill_root_el	= ocfs2_dinode_fill_root_el,
 168};
 169
 170static void ocfs2_dinode_set_last_eb_blk(struct ocfs2_extent_tree *et,
 171					 u64 blkno)
 172{
 173	struct ocfs2_dinode *di = et->et_object;
 174
 175	BUG_ON(et->et_ops != &ocfs2_dinode_et_ops);
 176	di->i_last_eb_blk = cpu_to_le64(blkno);
 177}
 178
 179static u64 ocfs2_dinode_get_last_eb_blk(struct ocfs2_extent_tree *et)
 180{
 181	struct ocfs2_dinode *di = et->et_object;
 182
 183	BUG_ON(et->et_ops != &ocfs2_dinode_et_ops);
 184	return le64_to_cpu(di->i_last_eb_blk);
 185}
 186
 187static void ocfs2_dinode_update_clusters(struct ocfs2_extent_tree *et,
 188					 u32 clusters)
 189{
 190	struct ocfs2_inode_info *oi = cache_info_to_inode(et->et_ci);
 191	struct ocfs2_dinode *di = et->et_object;
 192
 193	le32_add_cpu(&di->i_clusters, clusters);
 194	spin_lock(&oi->ip_lock);
 195	oi->ip_clusters = le32_to_cpu(di->i_clusters);
 196	spin_unlock(&oi->ip_lock);
 197}
 198
 199static void ocfs2_dinode_extent_map_insert(struct ocfs2_extent_tree *et,
 200					   struct ocfs2_extent_rec *rec)
 201{
 202	struct inode *inode = &cache_info_to_inode(et->et_ci)->vfs_inode;
 203
 204	ocfs2_extent_map_insert_rec(inode, rec);
 205}
 206
 207static void ocfs2_dinode_extent_map_truncate(struct ocfs2_extent_tree *et,
 208					     u32 clusters)
 209{
 210	struct inode *inode = &cache_info_to_inode(et->et_ci)->vfs_inode;
 211
 212	ocfs2_extent_map_trunc(inode, clusters);
 213}
 214
 215static int ocfs2_dinode_insert_check(struct ocfs2_extent_tree *et,
 216				     struct ocfs2_extent_rec *rec)
 217{
 218	struct ocfs2_inode_info *oi = cache_info_to_inode(et->et_ci);
 219	struct ocfs2_super *osb = OCFS2_SB(oi->vfs_inode.i_sb);
 220
 221	BUG_ON(oi->ip_dyn_features & OCFS2_INLINE_DATA_FL);
 222	mlog_bug_on_msg(!ocfs2_sparse_alloc(osb) &&
 223			(oi->ip_clusters != le32_to_cpu(rec->e_cpos)),
 224			"Device %s, asking for sparse allocation: inode %llu, "
 225			"cpos %u, clusters %u\n",
 226			osb->dev_str,
 227			(unsigned long long)oi->ip_blkno,
 228			rec->e_cpos, oi->ip_clusters);
 229
 230	return 0;
 231}
 232
 233static int ocfs2_dinode_sanity_check(struct ocfs2_extent_tree *et)
 234{
 235	struct ocfs2_dinode *di = et->et_object;
 236
 237	BUG_ON(et->et_ops != &ocfs2_dinode_et_ops);
 238	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
 239
 240	return 0;
 241}
 242
 243static void ocfs2_dinode_fill_root_el(struct ocfs2_extent_tree *et)
 244{
 245	struct ocfs2_dinode *di = et->et_object;
 246
 247	et->et_root_el = &di->id2.i_list;
 248}
 249
 250
 251static void ocfs2_xattr_value_fill_root_el(struct ocfs2_extent_tree *et)
 252{
 253	struct ocfs2_xattr_value_buf *vb = et->et_object;
 254
 255	et->et_root_el = &vb->vb_xv->xr_list;
 256}
 257
 258static void ocfs2_xattr_value_set_last_eb_blk(struct ocfs2_extent_tree *et,
 259					      u64 blkno)
 260{
 261	struct ocfs2_xattr_value_buf *vb = et->et_object;
 262
 263	vb->vb_xv->xr_last_eb_blk = cpu_to_le64(blkno);
 264}
 265
 266static u64 ocfs2_xattr_value_get_last_eb_blk(struct ocfs2_extent_tree *et)
 267{
 268	struct ocfs2_xattr_value_buf *vb = et->et_object;
 269
 270	return le64_to_cpu(vb->vb_xv->xr_last_eb_blk);
 271}
 272
 273static void ocfs2_xattr_value_update_clusters(struct ocfs2_extent_tree *et,
 274					      u32 clusters)
 275{
 276	struct ocfs2_xattr_value_buf *vb = et->et_object;
 277
 278	le32_add_cpu(&vb->vb_xv->xr_clusters, clusters);
 279}
 280
 281static const struct ocfs2_extent_tree_operations ocfs2_xattr_value_et_ops = {
 282	.eo_set_last_eb_blk	= ocfs2_xattr_value_set_last_eb_blk,
 283	.eo_get_last_eb_blk	= ocfs2_xattr_value_get_last_eb_blk,
 284	.eo_update_clusters	= ocfs2_xattr_value_update_clusters,
 285	.eo_fill_root_el	= ocfs2_xattr_value_fill_root_el,
 286};
 287
 288static void ocfs2_xattr_tree_fill_root_el(struct ocfs2_extent_tree *et)
 289{
 290	struct ocfs2_xattr_block *xb = et->et_object;
 291
 292	et->et_root_el = &xb->xb_attrs.xb_root.xt_list;
 293}
 294
 295static void ocfs2_xattr_tree_fill_max_leaf_clusters(struct ocfs2_extent_tree *et)
 296{
 297	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
 298	et->et_max_leaf_clusters =
 299		ocfs2_clusters_for_bytes(sb, OCFS2_MAX_XATTR_TREE_LEAF_SIZE);
 300}
 301
 302static void ocfs2_xattr_tree_set_last_eb_blk(struct ocfs2_extent_tree *et,
 303					     u64 blkno)
 304{
 305	struct ocfs2_xattr_block *xb = et->et_object;
 306	struct ocfs2_xattr_tree_root *xt = &xb->xb_attrs.xb_root;
 307
 308	xt->xt_last_eb_blk = cpu_to_le64(blkno);
 309}
 310
 311static u64 ocfs2_xattr_tree_get_last_eb_blk(struct ocfs2_extent_tree *et)
 312{
 313	struct ocfs2_xattr_block *xb = et->et_object;
 314	struct ocfs2_xattr_tree_root *xt = &xb->xb_attrs.xb_root;
 315
 316	return le64_to_cpu(xt->xt_last_eb_blk);
 317}
 318
 319static void ocfs2_xattr_tree_update_clusters(struct ocfs2_extent_tree *et,
 320					     u32 clusters)
 321{
 322	struct ocfs2_xattr_block *xb = et->et_object;
 323
 324	le32_add_cpu(&xb->xb_attrs.xb_root.xt_clusters, clusters);
 325}
 326
 327static const struct ocfs2_extent_tree_operations ocfs2_xattr_tree_et_ops = {
 328	.eo_set_last_eb_blk	= ocfs2_xattr_tree_set_last_eb_blk,
 329	.eo_get_last_eb_blk	= ocfs2_xattr_tree_get_last_eb_blk,
 330	.eo_update_clusters	= ocfs2_xattr_tree_update_clusters,
 331	.eo_fill_root_el	= ocfs2_xattr_tree_fill_root_el,
 332	.eo_fill_max_leaf_clusters = ocfs2_xattr_tree_fill_max_leaf_clusters,
 333};
 334
 335static void ocfs2_dx_root_set_last_eb_blk(struct ocfs2_extent_tree *et,
 336					  u64 blkno)
 337{
 338	struct ocfs2_dx_root_block *dx_root = et->et_object;
 339
 340	dx_root->dr_last_eb_blk = cpu_to_le64(blkno);
 341}
 342
 343static u64 ocfs2_dx_root_get_last_eb_blk(struct ocfs2_extent_tree *et)
 344{
 345	struct ocfs2_dx_root_block *dx_root = et->et_object;
 346
 347	return le64_to_cpu(dx_root->dr_last_eb_blk);
 348}
 349
 350static void ocfs2_dx_root_update_clusters(struct ocfs2_extent_tree *et,
 351					  u32 clusters)
 352{
 353	struct ocfs2_dx_root_block *dx_root = et->et_object;
 354
 355	le32_add_cpu(&dx_root->dr_clusters, clusters);
 356}
 357
 358static int ocfs2_dx_root_sanity_check(struct ocfs2_extent_tree *et)
 359{
 360	struct ocfs2_dx_root_block *dx_root = et->et_object;
 361
 362	BUG_ON(!OCFS2_IS_VALID_DX_ROOT(dx_root));
 363
 364	return 0;
 365}
 366
 367static void ocfs2_dx_root_fill_root_el(struct ocfs2_extent_tree *et)
 368{
 369	struct ocfs2_dx_root_block *dx_root = et->et_object;
 370
 371	et->et_root_el = &dx_root->dr_list;
 372}
 373
 374static const struct ocfs2_extent_tree_operations ocfs2_dx_root_et_ops = {
 375	.eo_set_last_eb_blk	= ocfs2_dx_root_set_last_eb_blk,
 376	.eo_get_last_eb_blk	= ocfs2_dx_root_get_last_eb_blk,
 377	.eo_update_clusters	= ocfs2_dx_root_update_clusters,
 378	.eo_sanity_check	= ocfs2_dx_root_sanity_check,
 379	.eo_fill_root_el	= ocfs2_dx_root_fill_root_el,
 380};
 381
 382static void ocfs2_refcount_tree_fill_root_el(struct ocfs2_extent_tree *et)
 383{
 384	struct ocfs2_refcount_block *rb = et->et_object;
 385
 386	et->et_root_el = &rb->rf_list;
 387}
 388
 389static void ocfs2_refcount_tree_set_last_eb_blk(struct ocfs2_extent_tree *et,
 390						u64 blkno)
 391{
 392	struct ocfs2_refcount_block *rb = et->et_object;
 393
 394	rb->rf_last_eb_blk = cpu_to_le64(blkno);
 395}
 396
 397static u64 ocfs2_refcount_tree_get_last_eb_blk(struct ocfs2_extent_tree *et)
 398{
 399	struct ocfs2_refcount_block *rb = et->et_object;
 400
 401	return le64_to_cpu(rb->rf_last_eb_blk);
 402}
 403
 404static void ocfs2_refcount_tree_update_clusters(struct ocfs2_extent_tree *et,
 405						u32 clusters)
 406{
 407	struct ocfs2_refcount_block *rb = et->et_object;
 408
 409	le32_add_cpu(&rb->rf_clusters, clusters);
 410}
 411
 412static enum ocfs2_contig_type
 413ocfs2_refcount_tree_extent_contig(struct ocfs2_extent_tree *et,
 414				  struct ocfs2_extent_rec *ext,
 415				  struct ocfs2_extent_rec *insert_rec)
 416{
 417	return CONTIG_NONE;
 418}
 419
 420static const struct ocfs2_extent_tree_operations ocfs2_refcount_tree_et_ops = {
 421	.eo_set_last_eb_blk	= ocfs2_refcount_tree_set_last_eb_blk,
 422	.eo_get_last_eb_blk	= ocfs2_refcount_tree_get_last_eb_blk,
 423	.eo_update_clusters	= ocfs2_refcount_tree_update_clusters,
 424	.eo_fill_root_el	= ocfs2_refcount_tree_fill_root_el,
 425	.eo_extent_contig	= ocfs2_refcount_tree_extent_contig,
 426};
 427
 428static void __ocfs2_init_extent_tree(struct ocfs2_extent_tree *et,
 429				     struct ocfs2_caching_info *ci,
 430				     struct buffer_head *bh,
 431				     ocfs2_journal_access_func access,
 432				     void *obj,
 433				     const struct ocfs2_extent_tree_operations *ops)
 434{
 435	et->et_ops = ops;
 436	et->et_root_bh = bh;
 437	et->et_ci = ci;
 438	et->et_root_journal_access = access;
 439	if (!obj)
 440		obj = (void *)bh->b_data;
 441	et->et_object = obj;
 442	et->et_dealloc = NULL;
 443
 444	et->et_ops->eo_fill_root_el(et);
 445	if (!et->et_ops->eo_fill_max_leaf_clusters)
 446		et->et_max_leaf_clusters = 0;
 447	else
 448		et->et_ops->eo_fill_max_leaf_clusters(et);
 449}
 450
 451void ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree *et,
 452				   struct ocfs2_caching_info *ci,
 453				   struct buffer_head *bh)
 454{
 455	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_di,
 456				 NULL, &ocfs2_dinode_et_ops);
 457}
 458
 459void ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree *et,
 460				       struct ocfs2_caching_info *ci,
 461				       struct buffer_head *bh)
 462{
 463	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_xb,
 464				 NULL, &ocfs2_xattr_tree_et_ops);
 465}
 466
 467void ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree *et,
 468					struct ocfs2_caching_info *ci,
 469					struct ocfs2_xattr_value_buf *vb)
 470{
 471	__ocfs2_init_extent_tree(et, ci, vb->vb_bh, vb->vb_access, vb,
 472				 &ocfs2_xattr_value_et_ops);
 473}
 474
 475void ocfs2_init_dx_root_extent_tree(struct ocfs2_extent_tree *et,
 476				    struct ocfs2_caching_info *ci,
 477				    struct buffer_head *bh)
 478{
 479	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_dr,
 480				 NULL, &ocfs2_dx_root_et_ops);
 481}
 482
 483void ocfs2_init_refcount_extent_tree(struct ocfs2_extent_tree *et,
 484				     struct ocfs2_caching_info *ci,
 485				     struct buffer_head *bh)
 486{
 487	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_rb,
 488				 NULL, &ocfs2_refcount_tree_et_ops);
 489}
 490
 491static inline void ocfs2_et_set_last_eb_blk(struct ocfs2_extent_tree *et,
 492					    u64 new_last_eb_blk)
 493{
 494	et->et_ops->eo_set_last_eb_blk(et, new_last_eb_blk);
 495}
 496
 497static inline u64 ocfs2_et_get_last_eb_blk(struct ocfs2_extent_tree *et)
 498{
 499	return et->et_ops->eo_get_last_eb_blk(et);
 500}
 501
 502static inline void ocfs2_et_update_clusters(struct ocfs2_extent_tree *et,
 503					    u32 clusters)
 504{
 505	et->et_ops->eo_update_clusters(et, clusters);
 506}
 507
 508static inline void ocfs2_et_extent_map_insert(struct ocfs2_extent_tree *et,
 509					      struct ocfs2_extent_rec *rec)
 510{
 511	if (et->et_ops->eo_extent_map_insert)
 512		et->et_ops->eo_extent_map_insert(et, rec);
 513}
 514
 515static inline void ocfs2_et_extent_map_truncate(struct ocfs2_extent_tree *et,
 516						u32 clusters)
 517{
 518	if (et->et_ops->eo_extent_map_truncate)
 519		et->et_ops->eo_extent_map_truncate(et, clusters);
 520}
 521
 522static inline int ocfs2_et_root_journal_access(handle_t *handle,
 523					       struct ocfs2_extent_tree *et,
 524					       int type)
 525{
 526	return et->et_root_journal_access(handle, et->et_ci, et->et_root_bh,
 527					  type);
 528}
 529
 530static inline enum ocfs2_contig_type
 531	ocfs2_et_extent_contig(struct ocfs2_extent_tree *et,
 532			       struct ocfs2_extent_rec *rec,
 533			       struct ocfs2_extent_rec *insert_rec)
 534{
 535	if (et->et_ops->eo_extent_contig)
 536		return et->et_ops->eo_extent_contig(et, rec, insert_rec);
 537
 538	return ocfs2_extent_rec_contig(
 539				ocfs2_metadata_cache_get_super(et->et_ci),
 540				rec, insert_rec);
 541}
 542
 543static inline int ocfs2_et_insert_check(struct ocfs2_extent_tree *et,
 544					struct ocfs2_extent_rec *rec)
 545{
 546	int ret = 0;
 547
 548	if (et->et_ops->eo_insert_check)
 549		ret = et->et_ops->eo_insert_check(et, rec);
 550	return ret;
 551}
 552
 553static inline int ocfs2_et_sanity_check(struct ocfs2_extent_tree *et)
 554{
 555	int ret = 0;
 556
 557	if (et->et_ops->eo_sanity_check)
 558		ret = et->et_ops->eo_sanity_check(et);
 559	return ret;
 560}
 561
 562static int ocfs2_cache_extent_block_free(struct ocfs2_cached_dealloc_ctxt *ctxt,
 563					 struct ocfs2_extent_block *eb);
 564static void ocfs2_adjust_rightmost_records(handle_t *handle,
 565					   struct ocfs2_extent_tree *et,
 566					   struct ocfs2_path *path,
 567					   struct ocfs2_extent_rec *insert_rec);
 568/*
 569 * Reset the actual path elements so that we can re-use the structure
 570 * to build another path. Generally, this involves freeing the buffer
 571 * heads.
 572 */
 573void ocfs2_reinit_path(struct ocfs2_path *path, int keep_root)
 574{
 575	int i, start = 0, depth = 0;
 576	struct ocfs2_path_item *node;
 577
 578	if (keep_root)
 579		start = 1;
 580
 581	for(i = start; i < path_num_items(path); i++) {
 582		node = &path->p_node[i];
 583
 584		brelse(node->bh);
 585		node->bh = NULL;
 586		node->el = NULL;
 587	}
 588
 589	/*
 590	 * Tree depth may change during truncate, or insert. If we're
 591	 * keeping the root extent list, then make sure that our path
 592	 * structure reflects the proper depth.
 593	 */
 594	if (keep_root)
 595		depth = le16_to_cpu(path_root_el(path)->l_tree_depth);
 596	else
 597		path_root_access(path) = NULL;
 598
 599	path->p_tree_depth = depth;
 600}
 601
 602void ocfs2_free_path(struct ocfs2_path *path)
 603{
 604	if (path) {
 605		ocfs2_reinit_path(path, 0);
 606		kfree(path);
 607	}
 608}
 609
 610/*
 611 * All the elements of src into dest. After this call, src could be freed
 612 * without affecting dest.
 613 *
 614 * Both paths should have the same root. Any non-root elements of dest
 615 * will be freed.
 616 */
 617static void ocfs2_cp_path(struct ocfs2_path *dest, struct ocfs2_path *src)
 618{
 619	int i;
 620
 621	BUG_ON(path_root_bh(dest) != path_root_bh(src));
 622	BUG_ON(path_root_el(dest) != path_root_el(src));
 623	BUG_ON(path_root_access(dest) != path_root_access(src));
 624
 625	ocfs2_reinit_path(dest, 1);
 626
 627	for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
 628		dest->p_node[i].bh = src->p_node[i].bh;
 629		dest->p_node[i].el = src->p_node[i].el;
 630
 631		if (dest->p_node[i].bh)
 632			get_bh(dest->p_node[i].bh);
 633	}
 634}
 635
 636/*
 637 * Make the *dest path the same as src and re-initialize src path to
 638 * have a root only.
 639 */
 640static void ocfs2_mv_path(struct ocfs2_path *dest, struct ocfs2_path *src)
 641{
 642	int i;
 643
 644	BUG_ON(path_root_bh(dest) != path_root_bh(src));
 645	BUG_ON(path_root_access(dest) != path_root_access(src));
 646
 647	for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
 648		brelse(dest->p_node[i].bh);
 649
 650		dest->p_node[i].bh = src->p_node[i].bh;
 651		dest->p_node[i].el = src->p_node[i].el;
 652
 653		src->p_node[i].bh = NULL;
 654		src->p_node[i].el = NULL;
 655	}
 656}
 657
 658/*
 659 * Insert an extent block at given index.
 660 *
 661 * This will not take an additional reference on eb_bh.
 662 */
 663static inline void ocfs2_path_insert_eb(struct ocfs2_path *path, int index,
 664					struct buffer_head *eb_bh)
 665{
 666	struct ocfs2_extent_block *eb = (struct ocfs2_extent_block *)eb_bh->b_data;
 667
 668	/*
 669	 * Right now, no root bh is an extent block, so this helps
 670	 * catch code errors with dinode trees. The assertion can be
 671	 * safely removed if we ever need to insert extent block
 672	 * structures at the root.
 673	 */
 674	BUG_ON(index == 0);
 675
 676	path->p_node[index].bh = eb_bh;
 677	path->p_node[index].el = &eb->h_list;
 678}
 679
 680static struct ocfs2_path *ocfs2_new_path(struct buffer_head *root_bh,
 681					 struct ocfs2_extent_list *root_el,
 682					 ocfs2_journal_access_func access)
 683{
 684	struct ocfs2_path *path;
 685
 686	BUG_ON(le16_to_cpu(root_el->l_tree_depth) >= OCFS2_MAX_PATH_DEPTH);
 687
 688	path = kzalloc(sizeof(*path), GFP_NOFS);
 689	if (path) {
 690		path->p_tree_depth = le16_to_cpu(root_el->l_tree_depth);
 691		get_bh(root_bh);
 692		path_root_bh(path) = root_bh;
 693		path_root_el(path) = root_el;
 694		path_root_access(path) = access;
 695	}
 696
 697	return path;
 698}
 699
 700struct ocfs2_path *ocfs2_new_path_from_path(struct ocfs2_path *path)
 701{
 702	return ocfs2_new_path(path_root_bh(path), path_root_el(path),
 703			      path_root_access(path));
 704}
 705
 706struct ocfs2_path *ocfs2_new_path_from_et(struct ocfs2_extent_tree *et)
 707{
 708	return ocfs2_new_path(et->et_root_bh, et->et_root_el,
 709			      et->et_root_journal_access);
 710}
 711
 712/*
 713 * Journal the buffer at depth idx.  All idx>0 are extent_blocks,
 714 * otherwise it's the root_access function.
 715 *
 716 * I don't like the way this function's name looks next to
 717 * ocfs2_journal_access_path(), but I don't have a better one.
 718 */
 719int ocfs2_path_bh_journal_access(handle_t *handle,
 720				 struct ocfs2_caching_info *ci,
 721				 struct ocfs2_path *path,
 722				 int idx)
 723{
 724	ocfs2_journal_access_func access = path_root_access(path);
 725
 726	if (!access)
 727		access = ocfs2_journal_access;
 728
 729	if (idx)
 730		access = ocfs2_journal_access_eb;
 731
 732	return access(handle, ci, path->p_node[idx].bh,
 733		      OCFS2_JOURNAL_ACCESS_WRITE);
 734}
 735
 736/*
 737 * Convenience function to journal all components in a path.
 738 */
 739int ocfs2_journal_access_path(struct ocfs2_caching_info *ci,
 740			      handle_t *handle,
 741			      struct ocfs2_path *path)
 742{
 743	int i, ret = 0;
 744
 745	if (!path)
 746		goto out;
 747
 748	for(i = 0; i < path_num_items(path); i++) {
 749		ret = ocfs2_path_bh_journal_access(handle, ci, path, i);
 750		if (ret < 0) {
 751			mlog_errno(ret);
 752			goto out;
 753		}
 754	}
 755
 756out:
 757	return ret;
 758}
 759
 760/*
 761 * Return the index of the extent record which contains cluster #v_cluster.
 762 * -1 is returned if it was not found.
 763 *
 764 * Should work fine on interior and exterior nodes.
 765 */
 766int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster)
 767{
 768	int ret = -1;
 769	int i;
 770	struct ocfs2_extent_rec *rec;
 771	u32 rec_end, rec_start, clusters;
 772
 773	for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
 774		rec = &el->l_recs[i];
 775
 776		rec_start = le32_to_cpu(rec->e_cpos);
 777		clusters = ocfs2_rec_clusters(el, rec);
 778
 779		rec_end = rec_start + clusters;
 780
 781		if (v_cluster >= rec_start && v_cluster < rec_end) {
 782			ret = i;
 783			break;
 784		}
 785	}
 786
 787	return ret;
 788}
 789
 790/*
 791 * NOTE: ocfs2_block_extent_contig(), ocfs2_extents_adjacent() and
 792 * ocfs2_extent_rec_contig only work properly against leaf nodes!
 793 */
 794static int ocfs2_block_extent_contig(struct super_block *sb,
 795				     struct ocfs2_extent_rec *ext,
 796				     u64 blkno)
 797{
 798	u64 blk_end = le64_to_cpu(ext->e_blkno);
 799
 800	blk_end += ocfs2_clusters_to_blocks(sb,
 801				    le16_to_cpu(ext->e_leaf_clusters));
 802
 803	return blkno == blk_end;
 804}
 805
 806static int ocfs2_extents_adjacent(struct ocfs2_extent_rec *left,
 807				  struct ocfs2_extent_rec *right)
 808{
 809	u32 left_range;
 810
 811	left_range = le32_to_cpu(left->e_cpos) +
 812		le16_to_cpu(left->e_leaf_clusters);
 813
 814	return (left_range == le32_to_cpu(right->e_cpos));
 815}
 816
 817static enum ocfs2_contig_type
 818	ocfs2_extent_rec_contig(struct super_block *sb,
 819				struct ocfs2_extent_rec *ext,
 820				struct ocfs2_extent_rec *insert_rec)
 821{
 822	u64 blkno = le64_to_cpu(insert_rec->e_blkno);
 823
 824	/*
 825	 * Refuse to coalesce extent records with different flag
 826	 * fields - we don't want to mix unwritten extents with user
 827	 * data.
 828	 */
 829	if (ext->e_flags != insert_rec->e_flags)
 830		return CONTIG_NONE;
 831
 832	if (ocfs2_extents_adjacent(ext, insert_rec) &&
 833	    ocfs2_block_extent_contig(sb, ext, blkno))
 834			return CONTIG_RIGHT;
 835
 836	blkno = le64_to_cpu(ext->e_blkno);
 837	if (ocfs2_extents_adjacent(insert_rec, ext) &&
 838	    ocfs2_block_extent_contig(sb, insert_rec, blkno))
 839		return CONTIG_LEFT;
 840
 841	return CONTIG_NONE;
 842}
 843
 844/*
 845 * NOTE: We can have pretty much any combination of contiguousness and
 846 * appending.
 847 *
 848 * The usefulness of APPEND_TAIL is more in that it lets us know that
 849 * we'll have to update the path to that leaf.
 850 */
 851enum ocfs2_append_type {
 852	APPEND_NONE = 0,
 853	APPEND_TAIL,
 854};
 855
 856enum ocfs2_split_type {
 857	SPLIT_NONE = 0,
 858	SPLIT_LEFT,
 859	SPLIT_RIGHT,
 860};
 861
 862struct ocfs2_insert_type {
 863	enum ocfs2_split_type	ins_split;
 864	enum ocfs2_append_type	ins_appending;
 865	enum ocfs2_contig_type	ins_contig;
 866	int			ins_contig_index;
 867	int			ins_tree_depth;
 868};
 869
 870struct ocfs2_merge_ctxt {
 871	enum ocfs2_contig_type	c_contig_type;
 872	int			c_has_empty_extent;
 873	int			c_split_covers_rec;
 874};
 875
 876static int ocfs2_validate_extent_block(struct super_block *sb,
 877				       struct buffer_head *bh)
 878{
 879	int rc;
 880	struct ocfs2_extent_block *eb =
 881		(struct ocfs2_extent_block *)bh->b_data;
 882
 883	trace_ocfs2_validate_extent_block((unsigned long long)bh->b_blocknr);
 884
 885	BUG_ON(!buffer_uptodate(bh));
 886
 887	/*
 888	 * If the ecc fails, we return the error but otherwise
 889	 * leave the filesystem running.  We know any error is
 890	 * local to this block.
 891	 */
 892	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &eb->h_check);
 893	if (rc) {
 894		mlog(ML_ERROR, "Checksum failed for extent block %llu\n",
 895		     (unsigned long long)bh->b_blocknr);
 896		return rc;
 897	}
 898
 899	/*
 900	 * Errors after here are fatal.
 901	 */
 902
 903	if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
 904		rc = ocfs2_error(sb,
 905				 "Extent block #%llu has bad signature %.*s\n",
 906				 (unsigned long long)bh->b_blocknr, 7,
 907				 eb->h_signature);
 908		goto bail;
 909	}
 910
 911	if (le64_to_cpu(eb->h_blkno) != bh->b_blocknr) {
 912		rc = ocfs2_error(sb,
 913				 "Extent block #%llu has an invalid h_blkno of %llu\n",
 914				 (unsigned long long)bh->b_blocknr,
 915				 (unsigned long long)le64_to_cpu(eb->h_blkno));
 916		goto bail;
 
 917	}
 918
 919	if (le32_to_cpu(eb->h_fs_generation) != OCFS2_SB(sb)->fs_generation)
 920		rc = ocfs2_error(sb,
 921				 "Extent block #%llu has an invalid h_fs_generation of #%u\n",
 922				 (unsigned long long)bh->b_blocknr,
 923				 le32_to_cpu(eb->h_fs_generation));
 924bail:
 925	return rc;
 
 
 
 926}
 927
 928int ocfs2_read_extent_block(struct ocfs2_caching_info *ci, u64 eb_blkno,
 929			    struct buffer_head **bh)
 930{
 931	int rc;
 932	struct buffer_head *tmp = *bh;
 933
 934	rc = ocfs2_read_block(ci, eb_blkno, &tmp,
 935			      ocfs2_validate_extent_block);
 936
 937	/* If ocfs2_read_block() got us a new bh, pass it up. */
 938	if (!rc && !*bh)
 939		*bh = tmp;
 940
 941	return rc;
 942}
 943
 944
 945/*
 946 * How many free extents have we got before we need more meta data?
 947 */
 948int ocfs2_num_free_extents(struct ocfs2_extent_tree *et)
 
 949{
 950	int retval;
 951	struct ocfs2_extent_list *el = NULL;
 952	struct ocfs2_extent_block *eb;
 953	struct buffer_head *eb_bh = NULL;
 954	u64 last_eb_blk = 0;
 955
 956	el = et->et_root_el;
 957	last_eb_blk = ocfs2_et_get_last_eb_blk(et);
 958
 959	if (last_eb_blk) {
 960		retval = ocfs2_read_extent_block(et->et_ci, last_eb_blk,
 961						 &eb_bh);
 962		if (retval < 0) {
 963			mlog_errno(retval);
 964			goto bail;
 965		}
 966		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
 967		el = &eb->h_list;
 968	}
 969
 970	BUG_ON(el->l_tree_depth != 0);
 971
 972	retval = le16_to_cpu(el->l_count) - le16_to_cpu(el->l_next_free_rec);
 973bail:
 974	brelse(eb_bh);
 975
 976	trace_ocfs2_num_free_extents(retval);
 977	return retval;
 978}
 979
 980/* expects array to already be allocated
 981 *
 982 * sets h_signature, h_blkno, h_suballoc_bit, h_suballoc_slot, and
 983 * l_count for you
 984 */
 985static int ocfs2_create_new_meta_bhs(handle_t *handle,
 986				     struct ocfs2_extent_tree *et,
 987				     int wanted,
 988				     struct ocfs2_alloc_context *meta_ac,
 989				     struct buffer_head *bhs[])
 990{
 991	int count, status, i;
 992	u16 suballoc_bit_start;
 993	u32 num_got;
 994	u64 suballoc_loc, first_blkno;
 995	struct ocfs2_super *osb =
 996		OCFS2_SB(ocfs2_metadata_cache_get_super(et->et_ci));
 997	struct ocfs2_extent_block *eb;
 998
 999	count = 0;
1000	while (count < wanted) {
1001		status = ocfs2_claim_metadata(handle,
1002					      meta_ac,
1003					      wanted - count,
1004					      &suballoc_loc,
1005					      &suballoc_bit_start,
1006					      &num_got,
1007					      &first_blkno);
1008		if (status < 0) {
1009			mlog_errno(status);
1010			goto bail;
1011		}
1012
1013		for(i = count;  i < (num_got + count); i++) {
1014			bhs[i] = sb_getblk(osb->sb, first_blkno);
1015			if (bhs[i] == NULL) {
1016				status = -ENOMEM;
1017				mlog_errno(status);
1018				goto bail;
1019			}
1020			ocfs2_set_new_buffer_uptodate(et->et_ci, bhs[i]);
1021
1022			status = ocfs2_journal_access_eb(handle, et->et_ci,
1023							 bhs[i],
1024							 OCFS2_JOURNAL_ACCESS_CREATE);
1025			if (status < 0) {
1026				mlog_errno(status);
1027				goto bail;
1028			}
1029
1030			memset(bhs[i]->b_data, 0, osb->sb->s_blocksize);
1031			eb = (struct ocfs2_extent_block *) bhs[i]->b_data;
1032			/* Ok, setup the minimal stuff here. */
1033			strcpy(eb->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE);
1034			eb->h_blkno = cpu_to_le64(first_blkno);
1035			eb->h_fs_generation = cpu_to_le32(osb->fs_generation);
1036			eb->h_suballoc_slot =
1037				cpu_to_le16(meta_ac->ac_alloc_slot);
1038			eb->h_suballoc_loc = cpu_to_le64(suballoc_loc);
1039			eb->h_suballoc_bit = cpu_to_le16(suballoc_bit_start);
1040			eb->h_list.l_count =
1041				cpu_to_le16(ocfs2_extent_recs_per_eb(osb->sb));
1042
1043			suballoc_bit_start++;
1044			first_blkno++;
1045
1046			/* We'll also be dirtied by the caller, so
1047			 * this isn't absolutely necessary. */
1048			ocfs2_journal_dirty(handle, bhs[i]);
1049		}
1050
1051		count += num_got;
1052	}
1053
1054	status = 0;
1055bail:
1056	if (status < 0) {
1057		for(i = 0; i < wanted; i++) {
1058			brelse(bhs[i]);
1059			bhs[i] = NULL;
1060		}
 
1061	}
1062	return status;
1063}
1064
1065/*
1066 * Helper function for ocfs2_add_branch() and ocfs2_shift_tree_depth().
1067 *
1068 * Returns the sum of the rightmost extent rec logical offset and
1069 * cluster count.
1070 *
1071 * ocfs2_add_branch() uses this to determine what logical cluster
1072 * value should be populated into the leftmost new branch records.
1073 *
1074 * ocfs2_shift_tree_depth() uses this to determine the # clusters
1075 * value for the new topmost tree record.
1076 */
1077static inline u32 ocfs2_sum_rightmost_rec(struct ocfs2_extent_list  *el)
1078{
1079	int i;
1080
1081	i = le16_to_cpu(el->l_next_free_rec) - 1;
1082
1083	return le32_to_cpu(el->l_recs[i].e_cpos) +
1084		ocfs2_rec_clusters(el, &el->l_recs[i]);
1085}
1086
1087/*
1088 * Change range of the branches in the right most path according to the leaf
1089 * extent block's rightmost record.
1090 */
1091static int ocfs2_adjust_rightmost_branch(handle_t *handle,
1092					 struct ocfs2_extent_tree *et)
1093{
1094	int status;
1095	struct ocfs2_path *path = NULL;
1096	struct ocfs2_extent_list *el;
1097	struct ocfs2_extent_rec *rec;
1098
1099	path = ocfs2_new_path_from_et(et);
1100	if (!path) {
1101		status = -ENOMEM;
1102		return status;
1103	}
1104
1105	status = ocfs2_find_path(et->et_ci, path, UINT_MAX);
1106	if (status < 0) {
1107		mlog_errno(status);
1108		goto out;
1109	}
1110
1111	status = ocfs2_extend_trans(handle, path_num_items(path));
1112	if (status < 0) {
1113		mlog_errno(status);
1114		goto out;
1115	}
1116
1117	status = ocfs2_journal_access_path(et->et_ci, handle, path);
1118	if (status < 0) {
1119		mlog_errno(status);
1120		goto out;
1121	}
1122
1123	el = path_leaf_el(path);
1124	rec = &el->l_recs[le16_to_cpu(el->l_next_free_rec) - 1];
1125
1126	ocfs2_adjust_rightmost_records(handle, et, path, rec);
1127
1128out:
1129	ocfs2_free_path(path);
1130	return status;
1131}
1132
1133/*
1134 * Add an entire tree branch to our inode. eb_bh is the extent block
1135 * to start at, if we don't want to start the branch at the root
1136 * structure.
1137 *
1138 * last_eb_bh is required as we have to update it's next_leaf pointer
1139 * for the new last extent block.
1140 *
1141 * the new branch will be 'empty' in the sense that every block will
1142 * contain a single record with cluster count == 0.
1143 */
1144static int ocfs2_add_branch(handle_t *handle,
1145			    struct ocfs2_extent_tree *et,
1146			    struct buffer_head *eb_bh,
1147			    struct buffer_head **last_eb_bh,
1148			    struct ocfs2_alloc_context *meta_ac)
1149{
1150	int status, new_blocks, i, block_given = 0;
1151	u64 next_blkno, new_last_eb_blk;
1152	struct buffer_head *bh;
1153	struct buffer_head **new_eb_bhs = NULL;
1154	struct ocfs2_extent_block *eb;
1155	struct ocfs2_extent_list  *eb_el;
1156	struct ocfs2_extent_list  *el;
1157	u32 new_cpos, root_end;
1158
1159	BUG_ON(!last_eb_bh || !*last_eb_bh);
1160
1161	if (eb_bh) {
1162		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
1163		el = &eb->h_list;
1164	} else
1165		el = et->et_root_el;
1166
1167	/* we never add a branch to a leaf. */
1168	BUG_ON(!el->l_tree_depth);
1169
1170	new_blocks = le16_to_cpu(el->l_tree_depth);
1171
1172	eb = (struct ocfs2_extent_block *)(*last_eb_bh)->b_data;
1173	new_cpos = ocfs2_sum_rightmost_rec(&eb->h_list);
1174	root_end = ocfs2_sum_rightmost_rec(et->et_root_el);
1175
1176	/*
1177	 * If there is a gap before the root end and the real end
1178	 * of the righmost leaf block, we need to remove the gap
1179	 * between new_cpos and root_end first so that the tree
1180	 * is consistent after we add a new branch(it will start
1181	 * from new_cpos).
1182	 */
1183	if (root_end > new_cpos) {
1184		trace_ocfs2_adjust_rightmost_branch(
1185			(unsigned long long)
1186			ocfs2_metadata_cache_owner(et->et_ci),
1187			root_end, new_cpos);
1188
1189		status = ocfs2_adjust_rightmost_branch(handle, et);
1190		if (status) {
1191			mlog_errno(status);
1192			goto bail;
1193		}
1194	}
1195
1196	/* allocate the number of new eb blocks we need */
1197	new_eb_bhs = kcalloc(new_blocks, sizeof(struct buffer_head *),
1198			     GFP_KERNEL);
1199	if (!new_eb_bhs) {
1200		status = -ENOMEM;
1201		mlog_errno(status);
1202		goto bail;
1203	}
1204
1205	/* Firstyly, try to reuse dealloc since we have already estimated how
1206	 * many extent blocks we may use.
1207	 */
1208	if (!ocfs2_is_dealloc_empty(et)) {
1209		status = ocfs2_reuse_blk_from_dealloc(handle, et,
1210						      new_eb_bhs, new_blocks,
1211						      &block_given);
1212		if (status < 0) {
1213			mlog_errno(status);
1214			goto bail;
1215		}
1216	}
1217
1218	BUG_ON(block_given > new_blocks);
1219
1220	if (block_given < new_blocks) {
1221		BUG_ON(!meta_ac);
1222		status = ocfs2_create_new_meta_bhs(handle, et,
1223						   new_blocks - block_given,
1224						   meta_ac,
1225						   &new_eb_bhs[block_given]);
1226		if (status < 0) {
1227			mlog_errno(status);
1228			goto bail;
1229		}
1230	}
1231
1232	/* Note: new_eb_bhs[new_blocks - 1] is the guy which will be
1233	 * linked with the rest of the tree.
1234	 * conversly, new_eb_bhs[0] is the new bottommost leaf.
1235	 *
1236	 * when we leave the loop, new_last_eb_blk will point to the
1237	 * newest leaf, and next_blkno will point to the topmost extent
1238	 * block. */
1239	next_blkno = new_last_eb_blk = 0;
1240	for(i = 0; i < new_blocks; i++) {
1241		bh = new_eb_bhs[i];
1242		eb = (struct ocfs2_extent_block *) bh->b_data;
1243		/* ocfs2_create_new_meta_bhs() should create it right! */
1244		BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));
1245		eb_el = &eb->h_list;
1246
1247		status = ocfs2_journal_access_eb(handle, et->et_ci, bh,
1248						 OCFS2_JOURNAL_ACCESS_CREATE);
1249		if (status < 0) {
1250			mlog_errno(status);
1251			goto bail;
1252		}
1253
1254		eb->h_next_leaf_blk = 0;
1255		eb_el->l_tree_depth = cpu_to_le16(i);
1256		eb_el->l_next_free_rec = cpu_to_le16(1);
1257		/*
1258		 * This actually counts as an empty extent as
1259		 * c_clusters == 0
1260		 */
1261		eb_el->l_recs[0].e_cpos = cpu_to_le32(new_cpos);
1262		eb_el->l_recs[0].e_blkno = cpu_to_le64(next_blkno);
1263		/*
1264		 * eb_el isn't always an interior node, but even leaf
1265		 * nodes want a zero'd flags and reserved field so
1266		 * this gets the whole 32 bits regardless of use.
1267		 */
1268		eb_el->l_recs[0].e_int_clusters = cpu_to_le32(0);
1269		if (!eb_el->l_tree_depth)
1270			new_last_eb_blk = le64_to_cpu(eb->h_blkno);
1271
1272		ocfs2_journal_dirty(handle, bh);
1273		next_blkno = le64_to_cpu(eb->h_blkno);
1274	}
1275
1276	/* This is a bit hairy. We want to update up to three blocks
1277	 * here without leaving any of them in an inconsistent state
1278	 * in case of error. We don't have to worry about
1279	 * journal_dirty erroring as it won't unless we've aborted the
1280	 * handle (in which case we would never be here) so reserving
1281	 * the write with journal_access is all we need to do. */
1282	status = ocfs2_journal_access_eb(handle, et->et_ci, *last_eb_bh,
1283					 OCFS2_JOURNAL_ACCESS_WRITE);
1284	if (status < 0) {
1285		mlog_errno(status);
1286		goto bail;
1287	}
1288	status = ocfs2_et_root_journal_access(handle, et,
1289					      OCFS2_JOURNAL_ACCESS_WRITE);
1290	if (status < 0) {
1291		mlog_errno(status);
1292		goto bail;
1293	}
1294	if (eb_bh) {
1295		status = ocfs2_journal_access_eb(handle, et->et_ci, eb_bh,
1296						 OCFS2_JOURNAL_ACCESS_WRITE);
1297		if (status < 0) {
1298			mlog_errno(status);
1299			goto bail;
1300		}
1301	}
1302
1303	/* Link the new branch into the rest of the tree (el will
1304	 * either be on the root_bh, or the extent block passed in. */
1305	i = le16_to_cpu(el->l_next_free_rec);
1306	el->l_recs[i].e_blkno = cpu_to_le64(next_blkno);
1307	el->l_recs[i].e_cpos = cpu_to_le32(new_cpos);
1308	el->l_recs[i].e_int_clusters = 0;
1309	le16_add_cpu(&el->l_next_free_rec, 1);
1310
1311	/* fe needs a new last extent block pointer, as does the
1312	 * next_leaf on the previously last-extent-block. */
1313	ocfs2_et_set_last_eb_blk(et, new_last_eb_blk);
1314
1315	eb = (struct ocfs2_extent_block *) (*last_eb_bh)->b_data;
1316	eb->h_next_leaf_blk = cpu_to_le64(new_last_eb_blk);
1317
1318	ocfs2_journal_dirty(handle, *last_eb_bh);
1319	ocfs2_journal_dirty(handle, et->et_root_bh);
1320	if (eb_bh)
1321		ocfs2_journal_dirty(handle, eb_bh);
1322
1323	/*
1324	 * Some callers want to track the rightmost leaf so pass it
1325	 * back here.
1326	 */
1327	brelse(*last_eb_bh);
1328	get_bh(new_eb_bhs[0]);
1329	*last_eb_bh = new_eb_bhs[0];
1330
1331	status = 0;
1332bail:
1333	if (new_eb_bhs) {
1334		for (i = 0; i < new_blocks; i++)
1335			brelse(new_eb_bhs[i]);
1336		kfree(new_eb_bhs);
1337	}
1338
1339	return status;
1340}
1341
1342/*
1343 * adds another level to the allocation tree.
1344 * returns back the new extent block so you can add a branch to it
1345 * after this call.
1346 */
1347static int ocfs2_shift_tree_depth(handle_t *handle,
1348				  struct ocfs2_extent_tree *et,
1349				  struct ocfs2_alloc_context *meta_ac,
1350				  struct buffer_head **ret_new_eb_bh)
1351{
1352	int status, i, block_given = 0;
1353	u32 new_clusters;
1354	struct buffer_head *new_eb_bh = NULL;
1355	struct ocfs2_extent_block *eb;
1356	struct ocfs2_extent_list  *root_el;
1357	struct ocfs2_extent_list  *eb_el;
1358
1359	if (!ocfs2_is_dealloc_empty(et)) {
1360		status = ocfs2_reuse_blk_from_dealloc(handle, et,
1361						      &new_eb_bh, 1,
1362						      &block_given);
1363	} else if (meta_ac) {
1364		status = ocfs2_create_new_meta_bhs(handle, et, 1, meta_ac,
1365						   &new_eb_bh);
1366
1367	} else {
1368		BUG();
1369	}
1370
1371	if (status < 0) {
1372		mlog_errno(status);
1373		goto bail;
1374	}
1375
1376	eb = (struct ocfs2_extent_block *) new_eb_bh->b_data;
1377	/* ocfs2_create_new_meta_bhs() should create it right! */
1378	BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));
1379
1380	eb_el = &eb->h_list;
1381	root_el = et->et_root_el;
1382
1383	status = ocfs2_journal_access_eb(handle, et->et_ci, new_eb_bh,
1384					 OCFS2_JOURNAL_ACCESS_CREATE);
1385	if (status < 0) {
1386		mlog_errno(status);
1387		goto bail;
1388	}
1389
1390	/* copy the root extent list data into the new extent block */
1391	eb_el->l_tree_depth = root_el->l_tree_depth;
1392	eb_el->l_next_free_rec = root_el->l_next_free_rec;
1393	for (i = 0; i < le16_to_cpu(root_el->l_next_free_rec); i++)
1394		eb_el->l_recs[i] = root_el->l_recs[i];
1395
1396	ocfs2_journal_dirty(handle, new_eb_bh);
1397
1398	status = ocfs2_et_root_journal_access(handle, et,
1399					      OCFS2_JOURNAL_ACCESS_WRITE);
1400	if (status < 0) {
1401		mlog_errno(status);
1402		goto bail;
1403	}
1404
1405	new_clusters = ocfs2_sum_rightmost_rec(eb_el);
1406
1407	/* update root_bh now */
1408	le16_add_cpu(&root_el->l_tree_depth, 1);
1409	root_el->l_recs[0].e_cpos = 0;
1410	root_el->l_recs[0].e_blkno = eb->h_blkno;
1411	root_el->l_recs[0].e_int_clusters = cpu_to_le32(new_clusters);
1412	for (i = 1; i < le16_to_cpu(root_el->l_next_free_rec); i++)
1413		memset(&root_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
1414	root_el->l_next_free_rec = cpu_to_le16(1);
1415
1416	/* If this is our 1st tree depth shift, then last_eb_blk
1417	 * becomes the allocated extent block */
1418	if (root_el->l_tree_depth == cpu_to_le16(1))
1419		ocfs2_et_set_last_eb_blk(et, le64_to_cpu(eb->h_blkno));
1420
1421	ocfs2_journal_dirty(handle, et->et_root_bh);
1422
1423	*ret_new_eb_bh = new_eb_bh;
1424	new_eb_bh = NULL;
1425	status = 0;
1426bail:
1427	brelse(new_eb_bh);
1428
1429	return status;
1430}
1431
1432/*
1433 * Should only be called when there is no space left in any of the
1434 * leaf nodes. What we want to do is find the lowest tree depth
1435 * non-leaf extent block with room for new records. There are three
1436 * valid results of this search:
1437 *
1438 * 1) a lowest extent block is found, then we pass it back in
1439 *    *lowest_eb_bh and return '0'
1440 *
1441 * 2) the search fails to find anything, but the root_el has room. We
1442 *    pass NULL back in *lowest_eb_bh, but still return '0'
1443 *
1444 * 3) the search fails to find anything AND the root_el is full, in
1445 *    which case we return > 0
1446 *
1447 * return status < 0 indicates an error.
1448 */
1449static int ocfs2_find_branch_target(struct ocfs2_extent_tree *et,
1450				    struct buffer_head **target_bh)
1451{
1452	int status = 0, i;
1453	u64 blkno;
1454	struct ocfs2_extent_block *eb;
1455	struct ocfs2_extent_list  *el;
1456	struct buffer_head *bh = NULL;
1457	struct buffer_head *lowest_bh = NULL;
1458
1459	*target_bh = NULL;
1460
1461	el = et->et_root_el;
1462
1463	while(le16_to_cpu(el->l_tree_depth) > 1) {
1464		if (le16_to_cpu(el->l_next_free_rec) == 0) {
1465			status = ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
1466					"Owner %llu has empty extent list (next_free_rec == 0)\n",
1467					(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci));
 
 
1468			goto bail;
1469		}
1470		i = le16_to_cpu(el->l_next_free_rec) - 1;
1471		blkno = le64_to_cpu(el->l_recs[i].e_blkno);
1472		if (!blkno) {
1473			status = ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
1474					"Owner %llu has extent list where extent # %d has no physical block start\n",
1475					(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci), i);
 
 
 
1476			goto bail;
1477		}
1478
1479		brelse(bh);
1480		bh = NULL;
1481
1482		status = ocfs2_read_extent_block(et->et_ci, blkno, &bh);
1483		if (status < 0) {
1484			mlog_errno(status);
1485			goto bail;
1486		}
1487
1488		eb = (struct ocfs2_extent_block *) bh->b_data;
1489		el = &eb->h_list;
1490
1491		if (le16_to_cpu(el->l_next_free_rec) <
1492		    le16_to_cpu(el->l_count)) {
1493			brelse(lowest_bh);
1494			lowest_bh = bh;
1495			get_bh(lowest_bh);
1496		}
1497	}
1498
1499	/* If we didn't find one and the fe doesn't have any room,
1500	 * then return '1' */
1501	el = et->et_root_el;
1502	if (!lowest_bh && (el->l_next_free_rec == el->l_count))
1503		status = 1;
1504
1505	*target_bh = lowest_bh;
1506bail:
1507	brelse(bh);
1508
1509	return status;
1510}
1511
1512/*
1513 * Grow a b-tree so that it has more records.
1514 *
1515 * We might shift the tree depth in which case existing paths should
1516 * be considered invalid.
1517 *
1518 * Tree depth after the grow is returned via *final_depth.
1519 *
1520 * *last_eb_bh will be updated by ocfs2_add_branch().
1521 */
1522static int ocfs2_grow_tree(handle_t *handle, struct ocfs2_extent_tree *et,
1523			   int *final_depth, struct buffer_head **last_eb_bh,
1524			   struct ocfs2_alloc_context *meta_ac)
1525{
1526	int ret, shift;
1527	struct ocfs2_extent_list *el = et->et_root_el;
1528	int depth = le16_to_cpu(el->l_tree_depth);
1529	struct buffer_head *bh = NULL;
1530
1531	BUG_ON(meta_ac == NULL && ocfs2_is_dealloc_empty(et));
1532
1533	shift = ocfs2_find_branch_target(et, &bh);
1534	if (shift < 0) {
1535		ret = shift;
1536		mlog_errno(ret);
1537		goto out;
1538	}
1539
1540	/* We traveled all the way to the bottom of the allocation tree
1541	 * and didn't find room for any more extents - we need to add
1542	 * another tree level */
1543	if (shift) {
1544		BUG_ON(bh);
1545		trace_ocfs2_grow_tree(
1546			(unsigned long long)
1547			ocfs2_metadata_cache_owner(et->et_ci),
1548			depth);
1549
1550		/* ocfs2_shift_tree_depth will return us a buffer with
1551		 * the new extent block (so we can pass that to
1552		 * ocfs2_add_branch). */
1553		ret = ocfs2_shift_tree_depth(handle, et, meta_ac, &bh);
1554		if (ret < 0) {
1555			mlog_errno(ret);
1556			goto out;
1557		}
1558		depth++;
1559		if (depth == 1) {
1560			/*
1561			 * Special case: we have room now if we shifted from
1562			 * tree_depth 0, so no more work needs to be done.
1563			 *
1564			 * We won't be calling add_branch, so pass
1565			 * back *last_eb_bh as the new leaf. At depth
1566			 * zero, it should always be null so there's
1567			 * no reason to brelse.
1568			 */
1569			BUG_ON(*last_eb_bh);
1570			get_bh(bh);
1571			*last_eb_bh = bh;
1572			goto out;
1573		}
1574	}
1575
1576	/* call ocfs2_add_branch to add the final part of the tree with
1577	 * the new data. */
1578	ret = ocfs2_add_branch(handle, et, bh, last_eb_bh,
1579			       meta_ac);
1580	if (ret < 0)
1581		mlog_errno(ret);
 
 
1582
1583out:
1584	if (final_depth)
1585		*final_depth = depth;
1586	brelse(bh);
1587	return ret;
1588}
1589
1590/*
1591 * This function will discard the rightmost extent record.
1592 */
1593static void ocfs2_shift_records_right(struct ocfs2_extent_list *el)
1594{
1595	int next_free = le16_to_cpu(el->l_next_free_rec);
1596	int count = le16_to_cpu(el->l_count);
1597	unsigned int num_bytes;
1598
1599	BUG_ON(!next_free);
1600	/* This will cause us to go off the end of our extent list. */
1601	BUG_ON(next_free >= count);
1602
1603	num_bytes = sizeof(struct ocfs2_extent_rec) * next_free;
1604
1605	memmove(&el->l_recs[1], &el->l_recs[0], num_bytes);
1606}
1607
1608static void ocfs2_rotate_leaf(struct ocfs2_extent_list *el,
1609			      struct ocfs2_extent_rec *insert_rec)
1610{
1611	int i, insert_index, next_free, has_empty, num_bytes;
1612	u32 insert_cpos = le32_to_cpu(insert_rec->e_cpos);
1613	struct ocfs2_extent_rec *rec;
1614
1615	next_free = le16_to_cpu(el->l_next_free_rec);
1616	has_empty = ocfs2_is_empty_extent(&el->l_recs[0]);
1617
1618	BUG_ON(!next_free);
1619
1620	/* The tree code before us didn't allow enough room in the leaf. */
1621	BUG_ON(el->l_next_free_rec == el->l_count && !has_empty);
1622
1623	/*
1624	 * The easiest way to approach this is to just remove the
1625	 * empty extent and temporarily decrement next_free.
1626	 */
1627	if (has_empty) {
1628		/*
1629		 * If next_free was 1 (only an empty extent), this
1630		 * loop won't execute, which is fine. We still want
1631		 * the decrement above to happen.
1632		 */
1633		for(i = 0; i < (next_free - 1); i++)
1634			el->l_recs[i] = el->l_recs[i+1];
1635
1636		next_free--;
1637	}
1638
1639	/*
1640	 * Figure out what the new record index should be.
1641	 */
1642	for(i = 0; i < next_free; i++) {
1643		rec = &el->l_recs[i];
1644
1645		if (insert_cpos < le32_to_cpu(rec->e_cpos))
1646			break;
1647	}
1648	insert_index = i;
1649
1650	trace_ocfs2_rotate_leaf(insert_cpos, insert_index,
1651				has_empty, next_free,
1652				le16_to_cpu(el->l_count));
1653
1654	BUG_ON(insert_index < 0);
1655	BUG_ON(insert_index >= le16_to_cpu(el->l_count));
1656	BUG_ON(insert_index > next_free);
1657
1658	/*
1659	 * No need to memmove if we're just adding to the tail.
1660	 */
1661	if (insert_index != next_free) {
1662		BUG_ON(next_free >= le16_to_cpu(el->l_count));
1663
1664		num_bytes = next_free - insert_index;
1665		num_bytes *= sizeof(struct ocfs2_extent_rec);
1666		memmove(&el->l_recs[insert_index + 1],
1667			&el->l_recs[insert_index],
1668			num_bytes);
1669	}
1670
1671	/*
1672	 * Either we had an empty extent, and need to re-increment or
1673	 * there was no empty extent on a non full rightmost leaf node,
1674	 * in which case we still need to increment.
1675	 */
1676	next_free++;
1677	el->l_next_free_rec = cpu_to_le16(next_free);
1678	/*
1679	 * Make sure none of the math above just messed up our tree.
1680	 */
1681	BUG_ON(le16_to_cpu(el->l_next_free_rec) > le16_to_cpu(el->l_count));
1682
1683	el->l_recs[insert_index] = *insert_rec;
1684
1685}
1686
1687static void ocfs2_remove_empty_extent(struct ocfs2_extent_list *el)
1688{
1689	int size, num_recs = le16_to_cpu(el->l_next_free_rec);
1690
1691	BUG_ON(num_recs == 0);
1692
1693	if (ocfs2_is_empty_extent(&el->l_recs[0])) {
1694		num_recs--;
1695		size = num_recs * sizeof(struct ocfs2_extent_rec);
1696		memmove(&el->l_recs[0], &el->l_recs[1], size);
1697		memset(&el->l_recs[num_recs], 0,
1698		       sizeof(struct ocfs2_extent_rec));
1699		el->l_next_free_rec = cpu_to_le16(num_recs);
1700	}
1701}
1702
1703/*
1704 * Create an empty extent record .
1705 *
1706 * l_next_free_rec may be updated.
1707 *
1708 * If an empty extent already exists do nothing.
1709 */
1710static void ocfs2_create_empty_extent(struct ocfs2_extent_list *el)
1711{
1712	int next_free = le16_to_cpu(el->l_next_free_rec);
1713
1714	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
1715
1716	if (next_free == 0)
1717		goto set_and_inc;
1718
1719	if (ocfs2_is_empty_extent(&el->l_recs[0]))
1720		return;
1721
1722	mlog_bug_on_msg(el->l_count == el->l_next_free_rec,
1723			"Asked to create an empty extent in a full list:\n"
1724			"count = %u, tree depth = %u",
1725			le16_to_cpu(el->l_count),
1726			le16_to_cpu(el->l_tree_depth));
1727
1728	ocfs2_shift_records_right(el);
1729
1730set_and_inc:
1731	le16_add_cpu(&el->l_next_free_rec, 1);
1732	memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
1733}
1734
1735/*
1736 * For a rotation which involves two leaf nodes, the "root node" is
1737 * the lowest level tree node which contains a path to both leafs. This
1738 * resulting set of information can be used to form a complete "subtree"
1739 *
1740 * This function is passed two full paths from the dinode down to a
1741 * pair of adjacent leaves. It's task is to figure out which path
1742 * index contains the subtree root - this can be the root index itself
1743 * in a worst-case rotation.
1744 *
1745 * The array index of the subtree root is passed back.
1746 */
1747int ocfs2_find_subtree_root(struct ocfs2_extent_tree *et,
1748			    struct ocfs2_path *left,
1749			    struct ocfs2_path *right)
1750{
1751	int i = 0;
1752
1753	/*
1754	 * Check that the caller passed in two paths from the same tree.
1755	 */
1756	BUG_ON(path_root_bh(left) != path_root_bh(right));
1757
1758	do {
1759		i++;
1760
1761		/*
1762		 * The caller didn't pass two adjacent paths.
1763		 */
1764		mlog_bug_on_msg(i > left->p_tree_depth,
1765				"Owner %llu, left depth %u, right depth %u\n"
1766				"left leaf blk %llu, right leaf blk %llu\n",
1767				(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
1768				left->p_tree_depth, right->p_tree_depth,
1769				(unsigned long long)path_leaf_bh(left)->b_blocknr,
1770				(unsigned long long)path_leaf_bh(right)->b_blocknr);
1771	} while (left->p_node[i].bh->b_blocknr ==
1772		 right->p_node[i].bh->b_blocknr);
1773
1774	return i - 1;
1775}
1776
1777typedef void (path_insert_t)(void *, struct buffer_head *);
1778
1779/*
1780 * Traverse a btree path in search of cpos, starting at root_el.
1781 *
1782 * This code can be called with a cpos larger than the tree, in which
1783 * case it will return the rightmost path.
1784 */
1785static int __ocfs2_find_path(struct ocfs2_caching_info *ci,
1786			     struct ocfs2_extent_list *root_el, u32 cpos,
1787			     path_insert_t *func, void *data)
1788{
1789	int i, ret = 0;
1790	u32 range;
1791	u64 blkno;
1792	struct buffer_head *bh = NULL;
1793	struct ocfs2_extent_block *eb;
1794	struct ocfs2_extent_list *el;
1795	struct ocfs2_extent_rec *rec;
1796
1797	el = root_el;
1798	while (el->l_tree_depth) {
1799		if (le16_to_cpu(el->l_next_free_rec) == 0) {
1800			ocfs2_error(ocfs2_metadata_cache_get_super(ci),
1801				    "Owner %llu has empty extent list at depth %u\n",
 
1802				    (unsigned long long)ocfs2_metadata_cache_owner(ci),
1803				    le16_to_cpu(el->l_tree_depth));
1804			ret = -EROFS;
1805			goto out;
1806
1807		}
1808
1809		for(i = 0; i < le16_to_cpu(el->l_next_free_rec) - 1; i++) {
1810			rec = &el->l_recs[i];
1811
1812			/*
1813			 * In the case that cpos is off the allocation
1814			 * tree, this should just wind up returning the
1815			 * rightmost record.
1816			 */
1817			range = le32_to_cpu(rec->e_cpos) +
1818				ocfs2_rec_clusters(el, rec);
1819			if (cpos >= le32_to_cpu(rec->e_cpos) && cpos < range)
1820			    break;
1821		}
1822
1823		blkno = le64_to_cpu(el->l_recs[i].e_blkno);
1824		if (blkno == 0) {
1825			ocfs2_error(ocfs2_metadata_cache_get_super(ci),
1826				    "Owner %llu has bad blkno in extent list at depth %u (index %d)\n",
 
1827				    (unsigned long long)ocfs2_metadata_cache_owner(ci),
1828				    le16_to_cpu(el->l_tree_depth), i);
1829			ret = -EROFS;
1830			goto out;
1831		}
1832
1833		brelse(bh);
1834		bh = NULL;
1835		ret = ocfs2_read_extent_block(ci, blkno, &bh);
1836		if (ret) {
1837			mlog_errno(ret);
1838			goto out;
1839		}
1840
1841		eb = (struct ocfs2_extent_block *) bh->b_data;
1842		el = &eb->h_list;
1843
1844		if (le16_to_cpu(el->l_next_free_rec) >
1845		    le16_to_cpu(el->l_count)) {
1846			ocfs2_error(ocfs2_metadata_cache_get_super(ci),
1847				    "Owner %llu has bad count in extent list at block %llu (next free=%u, count=%u)\n",
 
1848				    (unsigned long long)ocfs2_metadata_cache_owner(ci),
1849				    (unsigned long long)bh->b_blocknr,
1850				    le16_to_cpu(el->l_next_free_rec),
1851				    le16_to_cpu(el->l_count));
1852			ret = -EROFS;
1853			goto out;
1854		}
1855
1856		if (func)
1857			func(data, bh);
1858	}
1859
1860out:
1861	/*
1862	 * Catch any trailing bh that the loop didn't handle.
1863	 */
1864	brelse(bh);
1865
1866	return ret;
1867}
1868
1869/*
1870 * Given an initialized path (that is, it has a valid root extent
1871 * list), this function will traverse the btree in search of the path
1872 * which would contain cpos.
1873 *
1874 * The path traveled is recorded in the path structure.
1875 *
1876 * Note that this will not do any comparisons on leaf node extent
1877 * records, so it will work fine in the case that we just added a tree
1878 * branch.
1879 */
1880struct find_path_data {
1881	int index;
1882	struct ocfs2_path *path;
1883};
1884static void find_path_ins(void *data, struct buffer_head *bh)
1885{
1886	struct find_path_data *fp = data;
1887
1888	get_bh(bh);
1889	ocfs2_path_insert_eb(fp->path, fp->index, bh);
1890	fp->index++;
1891}
1892int ocfs2_find_path(struct ocfs2_caching_info *ci,
1893		    struct ocfs2_path *path, u32 cpos)
1894{
1895	struct find_path_data data;
1896
1897	data.index = 1;
1898	data.path = path;
1899	return __ocfs2_find_path(ci, path_root_el(path), cpos,
1900				 find_path_ins, &data);
1901}
1902
1903static void find_leaf_ins(void *data, struct buffer_head *bh)
1904{
1905	struct ocfs2_extent_block *eb =(struct ocfs2_extent_block *)bh->b_data;
1906	struct ocfs2_extent_list *el = &eb->h_list;
1907	struct buffer_head **ret = data;
1908
1909	/* We want to retain only the leaf block. */
1910	if (le16_to_cpu(el->l_tree_depth) == 0) {
1911		get_bh(bh);
1912		*ret = bh;
1913	}
1914}
1915/*
1916 * Find the leaf block in the tree which would contain cpos. No
1917 * checking of the actual leaf is done.
1918 *
1919 * Some paths want to call this instead of allocating a path structure
1920 * and calling ocfs2_find_path().
1921 *
1922 * This function doesn't handle non btree extent lists.
1923 */
1924int ocfs2_find_leaf(struct ocfs2_caching_info *ci,
1925		    struct ocfs2_extent_list *root_el, u32 cpos,
1926		    struct buffer_head **leaf_bh)
1927{
1928	int ret;
1929	struct buffer_head *bh = NULL;
1930
1931	ret = __ocfs2_find_path(ci, root_el, cpos, find_leaf_ins, &bh);
1932	if (ret) {
1933		mlog_errno(ret);
1934		goto out;
1935	}
1936
1937	*leaf_bh = bh;
1938out:
1939	return ret;
1940}
1941
1942/*
1943 * Adjust the adjacent records (left_rec, right_rec) involved in a rotation.
1944 *
1945 * Basically, we've moved stuff around at the bottom of the tree and
1946 * we need to fix up the extent records above the changes to reflect
1947 * the new changes.
1948 *
1949 * left_rec: the record on the left.
 
1950 * right_rec: the record to the right of left_rec
1951 * right_child_el: is the child list pointed to by right_rec
1952 *
1953 * By definition, this only works on interior nodes.
1954 */
1955static void ocfs2_adjust_adjacent_records(struct ocfs2_extent_rec *left_rec,
 
1956				  struct ocfs2_extent_rec *right_rec,
1957				  struct ocfs2_extent_list *right_child_el)
1958{
1959	u32 left_clusters, right_end;
1960
1961	/*
1962	 * Interior nodes never have holes. Their cpos is the cpos of
1963	 * the leftmost record in their child list. Their cluster
1964	 * count covers the full theoretical range of their child list
1965	 * - the range between their cpos and the cpos of the record
1966	 * immediately to their right.
1967	 */
1968	left_clusters = le32_to_cpu(right_child_el->l_recs[0].e_cpos);
1969	if (!ocfs2_rec_clusters(right_child_el, &right_child_el->l_recs[0])) {
1970		BUG_ON(right_child_el->l_tree_depth);
1971		BUG_ON(le16_to_cpu(right_child_el->l_next_free_rec) <= 1);
1972		left_clusters = le32_to_cpu(right_child_el->l_recs[1].e_cpos);
1973	}
1974	left_clusters -= le32_to_cpu(left_rec->e_cpos);
1975	left_rec->e_int_clusters = cpu_to_le32(left_clusters);
1976
1977	/*
1978	 * Calculate the rightmost cluster count boundary before
1979	 * moving cpos - we will need to adjust clusters after
1980	 * updating e_cpos to keep the same highest cluster count.
1981	 */
1982	right_end = le32_to_cpu(right_rec->e_cpos);
1983	right_end += le32_to_cpu(right_rec->e_int_clusters);
1984
1985	right_rec->e_cpos = left_rec->e_cpos;
1986	le32_add_cpu(&right_rec->e_cpos, left_clusters);
1987
1988	right_end -= le32_to_cpu(right_rec->e_cpos);
1989	right_rec->e_int_clusters = cpu_to_le32(right_end);
1990}
1991
1992/*
1993 * Adjust the adjacent root node records involved in a
1994 * rotation. left_el_blkno is passed in as a key so that we can easily
1995 * find it's index in the root list.
1996 */
1997static void ocfs2_adjust_root_records(struct ocfs2_extent_list *root_el,
1998				      struct ocfs2_extent_list *left_el,
1999				      struct ocfs2_extent_list *right_el,
2000				      u64 left_el_blkno)
2001{
2002	int i;
2003
2004	BUG_ON(le16_to_cpu(root_el->l_tree_depth) <=
2005	       le16_to_cpu(left_el->l_tree_depth));
2006
2007	for(i = 0; i < le16_to_cpu(root_el->l_next_free_rec) - 1; i++) {
2008		if (le64_to_cpu(root_el->l_recs[i].e_blkno) == left_el_blkno)
2009			break;
2010	}
2011
2012	/*
2013	 * The path walking code should have never returned a root and
2014	 * two paths which are not adjacent.
2015	 */
2016	BUG_ON(i >= (le16_to_cpu(root_el->l_next_free_rec) - 1));
2017
2018	ocfs2_adjust_adjacent_records(&root_el->l_recs[i],
2019				      &root_el->l_recs[i + 1], right_el);
2020}
2021
2022/*
2023 * We've changed a leaf block (in right_path) and need to reflect that
2024 * change back up the subtree.
2025 *
2026 * This happens in multiple places:
2027 *   - When we've moved an extent record from the left path leaf to the right
2028 *     path leaf to make room for an empty extent in the left path leaf.
2029 *   - When our insert into the right path leaf is at the leftmost edge
2030 *     and requires an update of the path immediately to it's left. This
2031 *     can occur at the end of some types of rotation and appending inserts.
2032 *   - When we've adjusted the last extent record in the left path leaf and the
2033 *     1st extent record in the right path leaf during cross extent block merge.
2034 */
2035static void ocfs2_complete_edge_insert(handle_t *handle,
2036				       struct ocfs2_path *left_path,
2037				       struct ocfs2_path *right_path,
2038				       int subtree_index)
2039{
2040	int i, idx;
2041	struct ocfs2_extent_list *el, *left_el, *right_el;
2042	struct ocfs2_extent_rec *left_rec, *right_rec;
2043	struct buffer_head *root_bh;
2044
2045	/*
2046	 * Update the counts and position values within all the
2047	 * interior nodes to reflect the leaf rotation we just did.
2048	 *
2049	 * The root node is handled below the loop.
2050	 *
2051	 * We begin the loop with right_el and left_el pointing to the
2052	 * leaf lists and work our way up.
2053	 *
2054	 * NOTE: within this loop, left_el and right_el always refer
2055	 * to the *child* lists.
2056	 */
2057	left_el = path_leaf_el(left_path);
2058	right_el = path_leaf_el(right_path);
2059	for(i = left_path->p_tree_depth - 1; i > subtree_index; i--) {
2060		trace_ocfs2_complete_edge_insert(i);
2061
2062		/*
2063		 * One nice property of knowing that all of these
2064		 * nodes are below the root is that we only deal with
2065		 * the leftmost right node record and the rightmost
2066		 * left node record.
2067		 */
2068		el = left_path->p_node[i].el;
2069		idx = le16_to_cpu(left_el->l_next_free_rec) - 1;
2070		left_rec = &el->l_recs[idx];
2071
2072		el = right_path->p_node[i].el;
2073		right_rec = &el->l_recs[0];
2074
2075		ocfs2_adjust_adjacent_records(left_rec, right_rec, right_el);
 
2076
2077		ocfs2_journal_dirty(handle, left_path->p_node[i].bh);
2078		ocfs2_journal_dirty(handle, right_path->p_node[i].bh);
2079
2080		/*
2081		 * Setup our list pointers now so that the current
2082		 * parents become children in the next iteration.
2083		 */
2084		left_el = left_path->p_node[i].el;
2085		right_el = right_path->p_node[i].el;
2086	}
2087
2088	/*
2089	 * At the root node, adjust the two adjacent records which
2090	 * begin our path to the leaves.
2091	 */
2092
2093	el = left_path->p_node[subtree_index].el;
2094	left_el = left_path->p_node[subtree_index + 1].el;
2095	right_el = right_path->p_node[subtree_index + 1].el;
2096
2097	ocfs2_adjust_root_records(el, left_el, right_el,
2098				  left_path->p_node[subtree_index + 1].bh->b_blocknr);
2099
2100	root_bh = left_path->p_node[subtree_index].bh;
2101
2102	ocfs2_journal_dirty(handle, root_bh);
2103}
2104
2105static int ocfs2_rotate_subtree_right(handle_t *handle,
2106				      struct ocfs2_extent_tree *et,
2107				      struct ocfs2_path *left_path,
2108				      struct ocfs2_path *right_path,
2109				      int subtree_index)
2110{
2111	int ret, i;
2112	struct buffer_head *right_leaf_bh;
2113	struct buffer_head *left_leaf_bh = NULL;
2114	struct buffer_head *root_bh;
2115	struct ocfs2_extent_list *right_el, *left_el;
2116	struct ocfs2_extent_rec move_rec;
2117
2118	left_leaf_bh = path_leaf_bh(left_path);
2119	left_el = path_leaf_el(left_path);
2120
2121	if (left_el->l_next_free_rec != left_el->l_count) {
2122		ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
2123			    "Inode %llu has non-full interior leaf node %llu (next free = %u)\n",
 
2124			    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2125			    (unsigned long long)left_leaf_bh->b_blocknr,
2126			    le16_to_cpu(left_el->l_next_free_rec));
2127		return -EROFS;
2128	}
2129
2130	/*
2131	 * This extent block may already have an empty record, so we
2132	 * return early if so.
2133	 */
2134	if (ocfs2_is_empty_extent(&left_el->l_recs[0]))
2135		return 0;
2136
2137	root_bh = left_path->p_node[subtree_index].bh;
2138	BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
2139
2140	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
2141					   subtree_index);
2142	if (ret) {
2143		mlog_errno(ret);
2144		goto out;
2145	}
2146
2147	for(i = subtree_index + 1; i < path_num_items(right_path); i++) {
2148		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2149						   right_path, i);
2150		if (ret) {
2151			mlog_errno(ret);
2152			goto out;
2153		}
2154
2155		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2156						   left_path, i);
2157		if (ret) {
2158			mlog_errno(ret);
2159			goto out;
2160		}
2161	}
2162
2163	right_leaf_bh = path_leaf_bh(right_path);
2164	right_el = path_leaf_el(right_path);
2165
2166	/* This is a code error, not a disk corruption. */
2167	mlog_bug_on_msg(!right_el->l_next_free_rec, "Inode %llu: Rotate fails "
2168			"because rightmost leaf block %llu is empty\n",
2169			(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2170			(unsigned long long)right_leaf_bh->b_blocknr);
2171
2172	ocfs2_create_empty_extent(right_el);
2173
2174	ocfs2_journal_dirty(handle, right_leaf_bh);
2175
2176	/* Do the copy now. */
2177	i = le16_to_cpu(left_el->l_next_free_rec) - 1;
2178	move_rec = left_el->l_recs[i];
2179	right_el->l_recs[0] = move_rec;
2180
2181	/*
2182	 * Clear out the record we just copied and shift everything
2183	 * over, leaving an empty extent in the left leaf.
2184	 *
2185	 * We temporarily subtract from next_free_rec so that the
2186	 * shift will lose the tail record (which is now defunct).
2187	 */
2188	le16_add_cpu(&left_el->l_next_free_rec, -1);
2189	ocfs2_shift_records_right(left_el);
2190	memset(&left_el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
2191	le16_add_cpu(&left_el->l_next_free_rec, 1);
2192
2193	ocfs2_journal_dirty(handle, left_leaf_bh);
2194
2195	ocfs2_complete_edge_insert(handle, left_path, right_path,
2196				   subtree_index);
2197
2198out:
2199	return ret;
2200}
2201
2202/*
2203 * Given a full path, determine what cpos value would return us a path
2204 * containing the leaf immediately to the left of the current one.
2205 *
2206 * Will return zero if the path passed in is already the leftmost path.
2207 */
2208int ocfs2_find_cpos_for_left_leaf(struct super_block *sb,
2209				  struct ocfs2_path *path, u32 *cpos)
2210{
2211	int i, j, ret = 0;
2212	u64 blkno;
2213	struct ocfs2_extent_list *el;
2214
2215	BUG_ON(path->p_tree_depth == 0);
2216
2217	*cpos = 0;
2218
2219	blkno = path_leaf_bh(path)->b_blocknr;
2220
2221	/* Start at the tree node just above the leaf and work our way up. */
2222	i = path->p_tree_depth - 1;
2223	while (i >= 0) {
2224		el = path->p_node[i].el;
2225
2226		/*
2227		 * Find the extent record just before the one in our
2228		 * path.
2229		 */
2230		for(j = 0; j < le16_to_cpu(el->l_next_free_rec); j++) {
2231			if (le64_to_cpu(el->l_recs[j].e_blkno) == blkno) {
2232				if (j == 0) {
2233					if (i == 0) {
2234						/*
2235						 * We've determined that the
2236						 * path specified is already
2237						 * the leftmost one - return a
2238						 * cpos of zero.
2239						 */
2240						goto out;
2241					}
2242					/*
2243					 * The leftmost record points to our
2244					 * leaf - we need to travel up the
2245					 * tree one level.
2246					 */
2247					goto next_node;
2248				}
2249
2250				*cpos = le32_to_cpu(el->l_recs[j - 1].e_cpos);
2251				*cpos = *cpos + ocfs2_rec_clusters(el,
2252							   &el->l_recs[j - 1]);
2253				*cpos = *cpos - 1;
2254				goto out;
2255			}
2256		}
2257
2258		/*
2259		 * If we got here, we never found a valid node where
2260		 * the tree indicated one should be.
2261		 */
2262		ocfs2_error(sb, "Invalid extent tree at extent block %llu\n",
 
2263			    (unsigned long long)blkno);
2264		ret = -EROFS;
2265		goto out;
2266
2267next_node:
2268		blkno = path->p_node[i].bh->b_blocknr;
2269		i--;
2270	}
2271
2272out:
2273	return ret;
2274}
2275
2276/*
2277 * Extend the transaction by enough credits to complete the rotation,
2278 * and still leave at least the original number of credits allocated
2279 * to this transaction.
2280 */
2281static int ocfs2_extend_rotate_transaction(handle_t *handle, int subtree_depth,
2282					   int op_credits,
2283					   struct ocfs2_path *path)
2284{
2285	int ret = 0;
2286	int credits = (path->p_tree_depth - subtree_depth) * 2 + 1 + op_credits;
2287
2288	if (jbd2_handle_buffer_credits(handle) < credits)
2289		ret = ocfs2_extend_trans(handle,
2290				credits - jbd2_handle_buffer_credits(handle));
2291
2292	return ret;
2293}
2294
2295/*
2296 * Trap the case where we're inserting into the theoretical range past
2297 * the _actual_ left leaf range. Otherwise, we'll rotate a record
2298 * whose cpos is less than ours into the right leaf.
2299 *
2300 * It's only necessary to look at the rightmost record of the left
2301 * leaf because the logic that calls us should ensure that the
2302 * theoretical ranges in the path components above the leaves are
2303 * correct.
2304 */
2305static int ocfs2_rotate_requires_path_adjustment(struct ocfs2_path *left_path,
2306						 u32 insert_cpos)
2307{
2308	struct ocfs2_extent_list *left_el;
2309	struct ocfs2_extent_rec *rec;
2310	int next_free;
2311
2312	left_el = path_leaf_el(left_path);
2313	next_free = le16_to_cpu(left_el->l_next_free_rec);
2314	rec = &left_el->l_recs[next_free - 1];
2315
2316	if (insert_cpos > le32_to_cpu(rec->e_cpos))
2317		return 1;
2318	return 0;
2319}
2320
2321static int ocfs2_leftmost_rec_contains(struct ocfs2_extent_list *el, u32 cpos)
2322{
2323	int next_free = le16_to_cpu(el->l_next_free_rec);
2324	unsigned int range;
2325	struct ocfs2_extent_rec *rec;
2326
2327	if (next_free == 0)
2328		return 0;
2329
2330	rec = &el->l_recs[0];
2331	if (ocfs2_is_empty_extent(rec)) {
2332		/* Empty list. */
2333		if (next_free == 1)
2334			return 0;
2335		rec = &el->l_recs[1];
2336	}
2337
2338	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
2339	if (cpos >= le32_to_cpu(rec->e_cpos) && cpos < range)
2340		return 1;
2341	return 0;
2342}
2343
2344/*
2345 * Rotate all the records in a btree right one record, starting at insert_cpos.
2346 *
2347 * The path to the rightmost leaf should be passed in.
2348 *
2349 * The array is assumed to be large enough to hold an entire path (tree depth).
2350 *
2351 * Upon successful return from this function:
2352 *
2353 * - The 'right_path' array will contain a path to the leaf block
2354 *   whose range contains e_cpos.
2355 * - That leaf block will have a single empty extent in list index 0.
2356 * - In the case that the rotation requires a post-insert update,
2357 *   *ret_left_path will contain a valid path which can be passed to
2358 *   ocfs2_insert_path().
2359 */
2360static int ocfs2_rotate_tree_right(handle_t *handle,
2361				   struct ocfs2_extent_tree *et,
2362				   enum ocfs2_split_type split,
2363				   u32 insert_cpos,
2364				   struct ocfs2_path *right_path,
2365				   struct ocfs2_path **ret_left_path)
2366{
2367	int ret, start, orig_credits = jbd2_handle_buffer_credits(handle);
2368	u32 cpos;
2369	struct ocfs2_path *left_path = NULL;
2370	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
2371
2372	*ret_left_path = NULL;
2373
2374	left_path = ocfs2_new_path_from_path(right_path);
2375	if (!left_path) {
2376		ret = -ENOMEM;
2377		mlog_errno(ret);
2378		goto out;
2379	}
2380
2381	ret = ocfs2_find_cpos_for_left_leaf(sb, right_path, &cpos);
2382	if (ret) {
2383		mlog_errno(ret);
2384		goto out;
2385	}
2386
2387	trace_ocfs2_rotate_tree_right(
2388		(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2389		insert_cpos, cpos);
2390
2391	/*
2392	 * What we want to do here is:
2393	 *
2394	 * 1) Start with the rightmost path.
2395	 *
2396	 * 2) Determine a path to the leaf block directly to the left
2397	 *    of that leaf.
2398	 *
2399	 * 3) Determine the 'subtree root' - the lowest level tree node
2400	 *    which contains a path to both leaves.
2401	 *
2402	 * 4) Rotate the subtree.
2403	 *
2404	 * 5) Find the next subtree by considering the left path to be
2405	 *    the new right path.
2406	 *
2407	 * The check at the top of this while loop also accepts
2408	 * insert_cpos == cpos because cpos is only a _theoretical_
2409	 * value to get us the left path - insert_cpos might very well
2410	 * be filling that hole.
2411	 *
2412	 * Stop at a cpos of '0' because we either started at the
2413	 * leftmost branch (i.e., a tree with one branch and a
2414	 * rotation inside of it), or we've gone as far as we can in
2415	 * rotating subtrees.
2416	 */
2417	while (cpos && insert_cpos <= cpos) {
2418		trace_ocfs2_rotate_tree_right(
2419			(unsigned long long)
2420			ocfs2_metadata_cache_owner(et->et_ci),
2421			insert_cpos, cpos);
2422
2423		ret = ocfs2_find_path(et->et_ci, left_path, cpos);
2424		if (ret) {
2425			mlog_errno(ret);
2426			goto out;
2427		}
2428
2429		mlog_bug_on_msg(path_leaf_bh(left_path) ==
2430				path_leaf_bh(right_path),
2431				"Owner %llu: error during insert of %u "
2432				"(left path cpos %u) results in two identical "
2433				"paths ending at %llu\n",
2434				(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2435				insert_cpos, cpos,
2436				(unsigned long long)
2437				path_leaf_bh(left_path)->b_blocknr);
2438
2439		if (split == SPLIT_NONE &&
2440		    ocfs2_rotate_requires_path_adjustment(left_path,
2441							  insert_cpos)) {
2442
2443			/*
2444			 * We've rotated the tree as much as we
2445			 * should. The rest is up to
2446			 * ocfs2_insert_path() to complete, after the
2447			 * record insertion. We indicate this
2448			 * situation by returning the left path.
2449			 *
2450			 * The reason we don't adjust the records here
2451			 * before the record insert is that an error
2452			 * later might break the rule where a parent
2453			 * record e_cpos will reflect the actual
2454			 * e_cpos of the 1st nonempty record of the
2455			 * child list.
2456			 */
2457			*ret_left_path = left_path;
2458			goto out_ret_path;
2459		}
2460
2461		start = ocfs2_find_subtree_root(et, left_path, right_path);
2462
2463		trace_ocfs2_rotate_subtree(start,
2464			(unsigned long long)
2465			right_path->p_node[start].bh->b_blocknr,
2466			right_path->p_tree_depth);
2467
2468		ret = ocfs2_extend_rotate_transaction(handle, start,
2469						      orig_credits, right_path);
2470		if (ret) {
2471			mlog_errno(ret);
2472			goto out;
2473		}
2474
2475		ret = ocfs2_rotate_subtree_right(handle, et, left_path,
2476						 right_path, start);
2477		if (ret) {
2478			mlog_errno(ret);
2479			goto out;
2480		}
2481
2482		if (split != SPLIT_NONE &&
2483		    ocfs2_leftmost_rec_contains(path_leaf_el(right_path),
2484						insert_cpos)) {
2485			/*
2486			 * A rotate moves the rightmost left leaf
2487			 * record over to the leftmost right leaf
2488			 * slot. If we're doing an extent split
2489			 * instead of a real insert, then we have to
2490			 * check that the extent to be split wasn't
2491			 * just moved over. If it was, then we can
2492			 * exit here, passing left_path back -
2493			 * ocfs2_split_extent() is smart enough to
2494			 * search both leaves.
2495			 */
2496			*ret_left_path = left_path;
2497			goto out_ret_path;
2498		}
2499
2500		/*
2501		 * There is no need to re-read the next right path
2502		 * as we know that it'll be our current left
2503		 * path. Optimize by copying values instead.
2504		 */
2505		ocfs2_mv_path(right_path, left_path);
2506
2507		ret = ocfs2_find_cpos_for_left_leaf(sb, right_path, &cpos);
2508		if (ret) {
2509			mlog_errno(ret);
2510			goto out;
2511		}
2512	}
2513
2514out:
2515	ocfs2_free_path(left_path);
2516
2517out_ret_path:
2518	return ret;
2519}
2520
2521static int ocfs2_update_edge_lengths(handle_t *handle,
2522				     struct ocfs2_extent_tree *et,
2523				     struct ocfs2_path *path)
2524{
2525	int i, idx, ret;
2526	struct ocfs2_extent_rec *rec;
2527	struct ocfs2_extent_list *el;
2528	struct ocfs2_extent_block *eb;
2529	u32 range;
2530
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2531	ret = ocfs2_journal_access_path(et->et_ci, handle, path);
2532	if (ret) {
2533		mlog_errno(ret);
2534		goto out;
2535	}
2536
2537	/* Path should always be rightmost. */
2538	eb = (struct ocfs2_extent_block *)path_leaf_bh(path)->b_data;
2539	BUG_ON(eb->h_next_leaf_blk != 0ULL);
2540
2541	el = &eb->h_list;
2542	BUG_ON(le16_to_cpu(el->l_next_free_rec) == 0);
2543	idx = le16_to_cpu(el->l_next_free_rec) - 1;
2544	rec = &el->l_recs[idx];
2545	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
2546
2547	for (i = 0; i < path->p_tree_depth; i++) {
2548		el = path->p_node[i].el;
2549		idx = le16_to_cpu(el->l_next_free_rec) - 1;
2550		rec = &el->l_recs[idx];
2551
2552		rec->e_int_clusters = cpu_to_le32(range);
2553		le32_add_cpu(&rec->e_int_clusters, -le32_to_cpu(rec->e_cpos));
2554
2555		ocfs2_journal_dirty(handle, path->p_node[i].bh);
2556	}
2557out:
2558	return ret;
2559}
2560
2561static void ocfs2_unlink_path(handle_t *handle,
2562			      struct ocfs2_extent_tree *et,
2563			      struct ocfs2_cached_dealloc_ctxt *dealloc,
2564			      struct ocfs2_path *path, int unlink_start)
2565{
2566	int ret, i;
2567	struct ocfs2_extent_block *eb;
2568	struct ocfs2_extent_list *el;
2569	struct buffer_head *bh;
2570
2571	for(i = unlink_start; i < path_num_items(path); i++) {
2572		bh = path->p_node[i].bh;
2573
2574		eb = (struct ocfs2_extent_block *)bh->b_data;
2575		/*
2576		 * Not all nodes might have had their final count
2577		 * decremented by the caller - handle this here.
2578		 */
2579		el = &eb->h_list;
2580		if (le16_to_cpu(el->l_next_free_rec) > 1) {
2581			mlog(ML_ERROR,
2582			     "Inode %llu, attempted to remove extent block "
2583			     "%llu with %u records\n",
2584			     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2585			     (unsigned long long)le64_to_cpu(eb->h_blkno),
2586			     le16_to_cpu(el->l_next_free_rec));
2587
2588			ocfs2_journal_dirty(handle, bh);
2589			ocfs2_remove_from_cache(et->et_ci, bh);
2590			continue;
2591		}
2592
2593		el->l_next_free_rec = 0;
2594		memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
2595
2596		ocfs2_journal_dirty(handle, bh);
2597
2598		ret = ocfs2_cache_extent_block_free(dealloc, eb);
2599		if (ret)
2600			mlog_errno(ret);
2601
2602		ocfs2_remove_from_cache(et->et_ci, bh);
2603	}
2604}
2605
2606static void ocfs2_unlink_subtree(handle_t *handle,
2607				 struct ocfs2_extent_tree *et,
2608				 struct ocfs2_path *left_path,
2609				 struct ocfs2_path *right_path,
2610				 int subtree_index,
2611				 struct ocfs2_cached_dealloc_ctxt *dealloc)
2612{
2613	int i;
2614	struct buffer_head *root_bh = left_path->p_node[subtree_index].bh;
2615	struct ocfs2_extent_list *root_el = left_path->p_node[subtree_index].el;
 
2616	struct ocfs2_extent_block *eb;
2617
 
 
2618	eb = (struct ocfs2_extent_block *)right_path->p_node[subtree_index + 1].bh->b_data;
2619
2620	for(i = 1; i < le16_to_cpu(root_el->l_next_free_rec); i++)
2621		if (root_el->l_recs[i].e_blkno == eb->h_blkno)
2622			break;
2623
2624	BUG_ON(i >= le16_to_cpu(root_el->l_next_free_rec));
2625
2626	memset(&root_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
2627	le16_add_cpu(&root_el->l_next_free_rec, -1);
2628
2629	eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
2630	eb->h_next_leaf_blk = 0;
2631
2632	ocfs2_journal_dirty(handle, root_bh);
2633	ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
2634
2635	ocfs2_unlink_path(handle, et, dealloc, right_path,
2636			  subtree_index + 1);
2637}
2638
2639static int ocfs2_rotate_subtree_left(handle_t *handle,
2640				     struct ocfs2_extent_tree *et,
2641				     struct ocfs2_path *left_path,
2642				     struct ocfs2_path *right_path,
2643				     int subtree_index,
2644				     struct ocfs2_cached_dealloc_ctxt *dealloc,
2645				     int *deleted)
2646{
2647	int ret, i, del_right_subtree = 0, right_has_empty = 0;
2648	struct buffer_head *root_bh, *et_root_bh = path_root_bh(right_path);
2649	struct ocfs2_extent_list *right_leaf_el, *left_leaf_el;
2650	struct ocfs2_extent_block *eb;
2651
2652	*deleted = 0;
2653
2654	right_leaf_el = path_leaf_el(right_path);
2655	left_leaf_el = path_leaf_el(left_path);
2656	root_bh = left_path->p_node[subtree_index].bh;
2657	BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
2658
2659	if (!ocfs2_is_empty_extent(&left_leaf_el->l_recs[0]))
2660		return 0;
2661
2662	eb = (struct ocfs2_extent_block *)path_leaf_bh(right_path)->b_data;
2663	if (ocfs2_is_empty_extent(&right_leaf_el->l_recs[0])) {
2664		/*
2665		 * It's legal for us to proceed if the right leaf is
2666		 * the rightmost one and it has an empty extent. There
2667		 * are two cases to handle - whether the leaf will be
2668		 * empty after removal or not. If the leaf isn't empty
2669		 * then just remove the empty extent up front. The
2670		 * next block will handle empty leaves by flagging
2671		 * them for unlink.
2672		 *
2673		 * Non rightmost leaves will throw -EAGAIN and the
2674		 * caller can manually move the subtree and retry.
2675		 */
2676
2677		if (eb->h_next_leaf_blk != 0ULL)
2678			return -EAGAIN;
2679
2680		if (le16_to_cpu(right_leaf_el->l_next_free_rec) > 1) {
2681			ret = ocfs2_journal_access_eb(handle, et->et_ci,
2682						      path_leaf_bh(right_path),
2683						      OCFS2_JOURNAL_ACCESS_WRITE);
2684			if (ret) {
2685				mlog_errno(ret);
2686				goto out;
2687			}
2688
2689			ocfs2_remove_empty_extent(right_leaf_el);
2690		} else
2691			right_has_empty = 1;
2692	}
2693
2694	if (eb->h_next_leaf_blk == 0ULL &&
2695	    le16_to_cpu(right_leaf_el->l_next_free_rec) == 1) {
2696		/*
2697		 * We have to update i_last_eb_blk during the meta
2698		 * data delete.
2699		 */
2700		ret = ocfs2_et_root_journal_access(handle, et,
2701						   OCFS2_JOURNAL_ACCESS_WRITE);
2702		if (ret) {
2703			mlog_errno(ret);
2704			goto out;
2705		}
2706
2707		del_right_subtree = 1;
2708	}
2709
2710	/*
2711	 * Getting here with an empty extent in the right path implies
2712	 * that it's the rightmost path and will be deleted.
2713	 */
2714	BUG_ON(right_has_empty && !del_right_subtree);
2715
2716	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
2717					   subtree_index);
2718	if (ret) {
2719		mlog_errno(ret);
2720		goto out;
2721	}
2722
2723	for(i = subtree_index + 1; i < path_num_items(right_path); i++) {
2724		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2725						   right_path, i);
2726		if (ret) {
2727			mlog_errno(ret);
2728			goto out;
2729		}
2730
2731		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2732						   left_path, i);
2733		if (ret) {
2734			mlog_errno(ret);
2735			goto out;
2736		}
2737	}
2738
2739	if (!right_has_empty) {
2740		/*
2741		 * Only do this if we're moving a real
2742		 * record. Otherwise, the action is delayed until
2743		 * after removal of the right path in which case we
2744		 * can do a simple shift to remove the empty extent.
2745		 */
2746		ocfs2_rotate_leaf(left_leaf_el, &right_leaf_el->l_recs[0]);
2747		memset(&right_leaf_el->l_recs[0], 0,
2748		       sizeof(struct ocfs2_extent_rec));
2749	}
2750	if (eb->h_next_leaf_blk == 0ULL) {
2751		/*
2752		 * Move recs over to get rid of empty extent, decrease
2753		 * next_free. This is allowed to remove the last
2754		 * extent in our leaf (setting l_next_free_rec to
2755		 * zero) - the delete code below won't care.
2756		 */
2757		ocfs2_remove_empty_extent(right_leaf_el);
2758	}
2759
2760	ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
2761	ocfs2_journal_dirty(handle, path_leaf_bh(right_path));
2762
2763	if (del_right_subtree) {
2764		ocfs2_unlink_subtree(handle, et, left_path, right_path,
2765				     subtree_index, dealloc);
2766		ret = ocfs2_update_edge_lengths(handle, et, left_path);
 
2767		if (ret) {
2768			mlog_errno(ret);
2769			goto out;
2770		}
2771
2772		eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
2773		ocfs2_et_set_last_eb_blk(et, le64_to_cpu(eb->h_blkno));
2774
2775		/*
2776		 * Removal of the extent in the left leaf was skipped
2777		 * above so we could delete the right path
2778		 * 1st.
2779		 */
2780		if (right_has_empty)
2781			ocfs2_remove_empty_extent(left_leaf_el);
2782
2783		ocfs2_journal_dirty(handle, et_root_bh);
2784
2785		*deleted = 1;
2786	} else
2787		ocfs2_complete_edge_insert(handle, left_path, right_path,
2788					   subtree_index);
2789
2790out:
2791	return ret;
2792}
2793
2794/*
2795 * Given a full path, determine what cpos value would return us a path
2796 * containing the leaf immediately to the right of the current one.
2797 *
2798 * Will return zero if the path passed in is already the rightmost path.
2799 *
2800 * This looks similar, but is subtly different to
2801 * ocfs2_find_cpos_for_left_leaf().
2802 */
2803int ocfs2_find_cpos_for_right_leaf(struct super_block *sb,
2804				   struct ocfs2_path *path, u32 *cpos)
2805{
2806	int i, j, ret = 0;
2807	u64 blkno;
2808	struct ocfs2_extent_list *el;
2809
2810	*cpos = 0;
2811
2812	if (path->p_tree_depth == 0)
2813		return 0;
2814
2815	blkno = path_leaf_bh(path)->b_blocknr;
2816
2817	/* Start at the tree node just above the leaf and work our way up. */
2818	i = path->p_tree_depth - 1;
2819	while (i >= 0) {
2820		int next_free;
2821
2822		el = path->p_node[i].el;
2823
2824		/*
2825		 * Find the extent record just after the one in our
2826		 * path.
2827		 */
2828		next_free = le16_to_cpu(el->l_next_free_rec);
2829		for(j = 0; j < le16_to_cpu(el->l_next_free_rec); j++) {
2830			if (le64_to_cpu(el->l_recs[j].e_blkno) == blkno) {
2831				if (j == (next_free - 1)) {
2832					if (i == 0) {
2833						/*
2834						 * We've determined that the
2835						 * path specified is already
2836						 * the rightmost one - return a
2837						 * cpos of zero.
2838						 */
2839						goto out;
2840					}
2841					/*
2842					 * The rightmost record points to our
2843					 * leaf - we need to travel up the
2844					 * tree one level.
2845					 */
2846					goto next_node;
2847				}
2848
2849				*cpos = le32_to_cpu(el->l_recs[j + 1].e_cpos);
2850				goto out;
2851			}
2852		}
2853
2854		/*
2855		 * If we got here, we never found a valid node where
2856		 * the tree indicated one should be.
2857		 */
2858		ocfs2_error(sb, "Invalid extent tree at extent block %llu\n",
 
2859			    (unsigned long long)blkno);
2860		ret = -EROFS;
2861		goto out;
2862
2863next_node:
2864		blkno = path->p_node[i].bh->b_blocknr;
2865		i--;
2866	}
2867
2868out:
2869	return ret;
2870}
2871
2872static int ocfs2_rotate_rightmost_leaf_left(handle_t *handle,
2873					    struct ocfs2_extent_tree *et,
2874					    struct ocfs2_path *path)
2875{
2876	int ret;
2877	struct buffer_head *bh = path_leaf_bh(path);
2878	struct ocfs2_extent_list *el = path_leaf_el(path);
2879
2880	if (!ocfs2_is_empty_extent(&el->l_recs[0]))
2881		return 0;
2882
2883	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, path,
2884					   path_num_items(path) - 1);
2885	if (ret) {
2886		mlog_errno(ret);
2887		goto out;
2888	}
2889
2890	ocfs2_remove_empty_extent(el);
2891	ocfs2_journal_dirty(handle, bh);
2892
2893out:
2894	return ret;
2895}
2896
2897static int __ocfs2_rotate_tree_left(handle_t *handle,
2898				    struct ocfs2_extent_tree *et,
2899				    int orig_credits,
2900				    struct ocfs2_path *path,
2901				    struct ocfs2_cached_dealloc_ctxt *dealloc,
2902				    struct ocfs2_path **empty_extent_path)
2903{
2904	int ret, subtree_root, deleted;
2905	u32 right_cpos;
2906	struct ocfs2_path *left_path = NULL;
2907	struct ocfs2_path *right_path = NULL;
2908	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
2909
2910	if (!ocfs2_is_empty_extent(&(path_leaf_el(path)->l_recs[0])))
2911		return 0;
2912
2913	*empty_extent_path = NULL;
2914
2915	ret = ocfs2_find_cpos_for_right_leaf(sb, path, &right_cpos);
2916	if (ret) {
2917		mlog_errno(ret);
2918		goto out;
2919	}
2920
2921	left_path = ocfs2_new_path_from_path(path);
2922	if (!left_path) {
2923		ret = -ENOMEM;
2924		mlog_errno(ret);
2925		goto out;
2926	}
2927
2928	ocfs2_cp_path(left_path, path);
2929
2930	right_path = ocfs2_new_path_from_path(path);
2931	if (!right_path) {
2932		ret = -ENOMEM;
2933		mlog_errno(ret);
2934		goto out;
2935	}
2936
2937	while (right_cpos) {
2938		ret = ocfs2_find_path(et->et_ci, right_path, right_cpos);
2939		if (ret) {
2940			mlog_errno(ret);
2941			goto out;
2942		}
2943
2944		subtree_root = ocfs2_find_subtree_root(et, left_path,
2945						       right_path);
2946
2947		trace_ocfs2_rotate_subtree(subtree_root,
2948		     (unsigned long long)
2949		     right_path->p_node[subtree_root].bh->b_blocknr,
2950		     right_path->p_tree_depth);
2951
2952		ret = ocfs2_extend_rotate_transaction(handle, 0,
2953						      orig_credits, left_path);
2954		if (ret) {
2955			mlog_errno(ret);
2956			goto out;
2957		}
2958
2959		/*
2960		 * Caller might still want to make changes to the
2961		 * tree root, so re-add it to the journal here.
2962		 */
2963		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2964						   left_path, 0);
2965		if (ret) {
2966			mlog_errno(ret);
2967			goto out;
2968		}
2969
2970		ret = ocfs2_rotate_subtree_left(handle, et, left_path,
2971						right_path, subtree_root,
2972						dealloc, &deleted);
2973		if (ret == -EAGAIN) {
2974			/*
2975			 * The rotation has to temporarily stop due to
2976			 * the right subtree having an empty
2977			 * extent. Pass it back to the caller for a
2978			 * fixup.
2979			 */
2980			*empty_extent_path = right_path;
2981			right_path = NULL;
2982			goto out;
2983		}
2984		if (ret) {
2985			mlog_errno(ret);
2986			goto out;
2987		}
2988
2989		/*
2990		 * The subtree rotate might have removed records on
2991		 * the rightmost edge. If so, then rotation is
2992		 * complete.
2993		 */
2994		if (deleted)
2995			break;
2996
2997		ocfs2_mv_path(left_path, right_path);
2998
2999		ret = ocfs2_find_cpos_for_right_leaf(sb, left_path,
3000						     &right_cpos);
3001		if (ret) {
3002			mlog_errno(ret);
3003			goto out;
3004		}
3005	}
3006
3007out:
3008	ocfs2_free_path(right_path);
3009	ocfs2_free_path(left_path);
3010
3011	return ret;
3012}
3013
3014static int ocfs2_remove_rightmost_path(handle_t *handle,
3015				struct ocfs2_extent_tree *et,
3016				struct ocfs2_path *path,
3017				struct ocfs2_cached_dealloc_ctxt *dealloc)
3018{
3019	int ret, subtree_index;
3020	u32 cpos;
3021	struct ocfs2_path *left_path = NULL;
3022	struct ocfs2_extent_block *eb;
3023	struct ocfs2_extent_list *el;
3024
 
3025	ret = ocfs2_et_sanity_check(et);
3026	if (ret)
3027		goto out;
 
 
 
 
 
 
 
 
 
 
 
3028
3029	ret = ocfs2_journal_access_path(et->et_ci, handle, path);
3030	if (ret) {
3031		mlog_errno(ret);
3032		goto out;
3033	}
3034
3035	ret = ocfs2_find_cpos_for_left_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
3036					    path, &cpos);
3037	if (ret) {
3038		mlog_errno(ret);
3039		goto out;
3040	}
3041
3042	if (cpos) {
3043		/*
3044		 * We have a path to the left of this one - it needs
3045		 * an update too.
3046		 */
3047		left_path = ocfs2_new_path_from_path(path);
3048		if (!left_path) {
3049			ret = -ENOMEM;
3050			mlog_errno(ret);
3051			goto out;
3052		}
3053
3054		ret = ocfs2_find_path(et->et_ci, left_path, cpos);
3055		if (ret) {
3056			mlog_errno(ret);
3057			goto out;
3058		}
3059
3060		ret = ocfs2_journal_access_path(et->et_ci, handle, left_path);
3061		if (ret) {
3062			mlog_errno(ret);
3063			goto out;
3064		}
3065
3066		subtree_index = ocfs2_find_subtree_root(et, left_path, path);
3067
3068		ocfs2_unlink_subtree(handle, et, left_path, path,
3069				     subtree_index, dealloc);
3070		ret = ocfs2_update_edge_lengths(handle, et, left_path);
 
3071		if (ret) {
3072			mlog_errno(ret);
3073			goto out;
3074		}
3075
3076		eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
3077		ocfs2_et_set_last_eb_blk(et, le64_to_cpu(eb->h_blkno));
3078	} else {
3079		/*
3080		 * 'path' is also the leftmost path which
3081		 * means it must be the only one. This gets
3082		 * handled differently because we want to
3083		 * revert the root back to having extents
3084		 * in-line.
3085		 */
3086		ocfs2_unlink_path(handle, et, dealloc, path, 1);
3087
3088		el = et->et_root_el;
3089		el->l_tree_depth = 0;
3090		el->l_next_free_rec = 0;
3091		memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
3092
3093		ocfs2_et_set_last_eb_blk(et, 0);
3094	}
3095
3096	ocfs2_journal_dirty(handle, path_root_bh(path));
3097
3098out:
3099	ocfs2_free_path(left_path);
3100	return ret;
3101}
3102
3103static int ocfs2_remove_rightmost_empty_extent(struct ocfs2_super *osb,
3104				struct ocfs2_extent_tree *et,
3105				struct ocfs2_path *path,
3106				struct ocfs2_cached_dealloc_ctxt *dealloc)
3107{
3108	handle_t *handle;
3109	int ret;
3110	int credits = path->p_tree_depth * 2 + 1;
3111
3112	handle = ocfs2_start_trans(osb, credits);
3113	if (IS_ERR(handle)) {
3114		ret = PTR_ERR(handle);
3115		mlog_errno(ret);
3116		return ret;
3117	}
3118
3119	ret = ocfs2_remove_rightmost_path(handle, et, path, dealloc);
3120	if (ret)
3121		mlog_errno(ret);
3122
3123	ocfs2_commit_trans(osb, handle);
3124	return ret;
3125}
3126
3127/*
3128 * Left rotation of btree records.
3129 *
3130 * In many ways, this is (unsurprisingly) the opposite of right
3131 * rotation. We start at some non-rightmost path containing an empty
3132 * extent in the leaf block. The code works its way to the rightmost
3133 * path by rotating records to the left in every subtree.
3134 *
3135 * This is used by any code which reduces the number of extent records
3136 * in a leaf. After removal, an empty record should be placed in the
3137 * leftmost list position.
3138 *
3139 * This won't handle a length update of the rightmost path records if
3140 * the rightmost tree leaf record is removed so the caller is
3141 * responsible for detecting and correcting that.
3142 */
3143static int ocfs2_rotate_tree_left(handle_t *handle,
3144				  struct ocfs2_extent_tree *et,
3145				  struct ocfs2_path *path,
3146				  struct ocfs2_cached_dealloc_ctxt *dealloc)
3147{
3148	int ret, orig_credits = jbd2_handle_buffer_credits(handle);
3149	struct ocfs2_path *tmp_path = NULL, *restart_path = NULL;
3150	struct ocfs2_extent_block *eb;
3151	struct ocfs2_extent_list *el;
3152
3153	el = path_leaf_el(path);
3154	if (!ocfs2_is_empty_extent(&el->l_recs[0]))
3155		return 0;
3156
3157	if (path->p_tree_depth == 0) {
3158rightmost_no_delete:
3159		/*
3160		 * Inline extents. This is trivially handled, so do
3161		 * it up front.
3162		 */
3163		ret = ocfs2_rotate_rightmost_leaf_left(handle, et, path);
3164		if (ret)
3165			mlog_errno(ret);
3166		goto out;
3167	}
3168
3169	/*
3170	 * Handle rightmost branch now. There's several cases:
3171	 *  1) simple rotation leaving records in there. That's trivial.
3172	 *  2) rotation requiring a branch delete - there's no more
3173	 *     records left. Two cases of this:
3174	 *     a) There are branches to the left.
3175	 *     b) This is also the leftmost (the only) branch.
3176	 *
3177	 *  1) is handled via ocfs2_rotate_rightmost_leaf_left()
3178	 *  2a) we need the left branch so that we can update it with the unlink
3179	 *  2b) we need to bring the root back to inline extents.
3180	 */
3181
3182	eb = (struct ocfs2_extent_block *)path_leaf_bh(path)->b_data;
3183	el = &eb->h_list;
3184	if (eb->h_next_leaf_blk == 0) {
3185		/*
3186		 * This gets a bit tricky if we're going to delete the
3187		 * rightmost path. Get the other cases out of the way
3188		 * 1st.
3189		 */
3190		if (le16_to_cpu(el->l_next_free_rec) > 1)
3191			goto rightmost_no_delete;
3192
3193		if (le16_to_cpu(el->l_next_free_rec) == 0) {
3194			ret = ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
3195					"Owner %llu has empty extent block at %llu\n",
3196					(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
3197					(unsigned long long)le64_to_cpu(eb->h_blkno));
 
3198			goto out;
3199		}
3200
3201		/*
3202		 * XXX: The caller can not trust "path" any more after
3203		 * this as it will have been deleted. What do we do?
3204		 *
3205		 * In theory the rotate-for-merge code will never get
3206		 * here because it'll always ask for a rotate in a
3207		 * nonempty list.
3208		 */
3209
3210		ret = ocfs2_remove_rightmost_path(handle, et, path,
3211						  dealloc);
3212		if (ret)
3213			mlog_errno(ret);
3214		goto out;
3215	}
3216
3217	/*
3218	 * Now we can loop, remembering the path we get from -EAGAIN
3219	 * and restarting from there.
3220	 */
3221try_rotate:
3222	ret = __ocfs2_rotate_tree_left(handle, et, orig_credits, path,
3223				       dealloc, &restart_path);
3224	if (ret && ret != -EAGAIN) {
3225		mlog_errno(ret);
3226		goto out;
3227	}
3228
3229	while (ret == -EAGAIN) {
3230		tmp_path = restart_path;
3231		restart_path = NULL;
3232
3233		ret = __ocfs2_rotate_tree_left(handle, et, orig_credits,
3234					       tmp_path, dealloc,
3235					       &restart_path);
3236		if (ret && ret != -EAGAIN) {
3237			mlog_errno(ret);
3238			goto out;
3239		}
3240
3241		ocfs2_free_path(tmp_path);
3242		tmp_path = NULL;
3243
3244		if (ret == 0)
3245			goto try_rotate;
3246	}
3247
3248out:
3249	ocfs2_free_path(tmp_path);
3250	ocfs2_free_path(restart_path);
3251	return ret;
3252}
3253
3254static void ocfs2_cleanup_merge(struct ocfs2_extent_list *el,
3255				int index)
3256{
3257	struct ocfs2_extent_rec *rec = &el->l_recs[index];
3258	unsigned int size;
3259
3260	if (rec->e_leaf_clusters == 0) {
3261		/*
3262		 * We consumed all of the merged-from record. An empty
3263		 * extent cannot exist anywhere but the 1st array
3264		 * position, so move things over if the merged-from
3265		 * record doesn't occupy that position.
3266		 *
3267		 * This creates a new empty extent so the caller
3268		 * should be smart enough to have removed any existing
3269		 * ones.
3270		 */
3271		if (index > 0) {
3272			BUG_ON(ocfs2_is_empty_extent(&el->l_recs[0]));
3273			size = index * sizeof(struct ocfs2_extent_rec);
3274			memmove(&el->l_recs[1], &el->l_recs[0], size);
3275		}
3276
3277		/*
3278		 * Always memset - the caller doesn't check whether it
3279		 * created an empty extent, so there could be junk in
3280		 * the other fields.
3281		 */
3282		memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
3283	}
3284}
3285
3286static int ocfs2_get_right_path(struct ocfs2_extent_tree *et,
3287				struct ocfs2_path *left_path,
3288				struct ocfs2_path **ret_right_path)
3289{
3290	int ret;
3291	u32 right_cpos;
3292	struct ocfs2_path *right_path = NULL;
3293	struct ocfs2_extent_list *left_el;
3294
3295	*ret_right_path = NULL;
3296
3297	/* This function shouldn't be called for non-trees. */
3298	BUG_ON(left_path->p_tree_depth == 0);
3299
3300	left_el = path_leaf_el(left_path);
3301	BUG_ON(left_el->l_next_free_rec != left_el->l_count);
3302
3303	ret = ocfs2_find_cpos_for_right_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
3304					     left_path, &right_cpos);
3305	if (ret) {
3306		mlog_errno(ret);
3307		goto out;
3308	}
3309
3310	/* This function shouldn't be called for the rightmost leaf. */
3311	BUG_ON(right_cpos == 0);
3312
3313	right_path = ocfs2_new_path_from_path(left_path);
3314	if (!right_path) {
3315		ret = -ENOMEM;
3316		mlog_errno(ret);
3317		goto out;
3318	}
3319
3320	ret = ocfs2_find_path(et->et_ci, right_path, right_cpos);
3321	if (ret) {
3322		mlog_errno(ret);
3323		goto out;
3324	}
3325
3326	*ret_right_path = right_path;
3327out:
3328	if (ret)
3329		ocfs2_free_path(right_path);
3330	return ret;
3331}
3332
3333/*
3334 * Remove split_rec clusters from the record at index and merge them
3335 * onto the beginning of the record "next" to it.
3336 * For index < l_count - 1, the next means the extent rec at index + 1.
3337 * For index == l_count - 1, the "next" means the 1st extent rec of the
3338 * next extent block.
3339 */
3340static int ocfs2_merge_rec_right(struct ocfs2_path *left_path,
3341				 handle_t *handle,
3342				 struct ocfs2_extent_tree *et,
3343				 struct ocfs2_extent_rec *split_rec,
3344				 int index)
3345{
3346	int ret, next_free, i;
3347	unsigned int split_clusters = le16_to_cpu(split_rec->e_leaf_clusters);
3348	struct ocfs2_extent_rec *left_rec;
3349	struct ocfs2_extent_rec *right_rec;
3350	struct ocfs2_extent_list *right_el;
3351	struct ocfs2_path *right_path = NULL;
3352	int subtree_index = 0;
3353	struct ocfs2_extent_list *el = path_leaf_el(left_path);
3354	struct buffer_head *bh = path_leaf_bh(left_path);
3355	struct buffer_head *root_bh = NULL;
3356
3357	BUG_ON(index >= le16_to_cpu(el->l_next_free_rec));
3358	left_rec = &el->l_recs[index];
3359
3360	if (index == le16_to_cpu(el->l_next_free_rec) - 1 &&
3361	    le16_to_cpu(el->l_next_free_rec) == le16_to_cpu(el->l_count)) {
3362		/* we meet with a cross extent block merge. */
3363		ret = ocfs2_get_right_path(et, left_path, &right_path);
3364		if (ret) {
3365			mlog_errno(ret);
3366			return ret;
3367		}
3368
3369		right_el = path_leaf_el(right_path);
3370		next_free = le16_to_cpu(right_el->l_next_free_rec);
3371		BUG_ON(next_free <= 0);
3372		right_rec = &right_el->l_recs[0];
3373		if (ocfs2_is_empty_extent(right_rec)) {
3374			BUG_ON(next_free <= 1);
3375			right_rec = &right_el->l_recs[1];
3376		}
3377
3378		BUG_ON(le32_to_cpu(left_rec->e_cpos) +
3379		       le16_to_cpu(left_rec->e_leaf_clusters) !=
3380		       le32_to_cpu(right_rec->e_cpos));
3381
3382		subtree_index = ocfs2_find_subtree_root(et, left_path,
3383							right_path);
3384
3385		ret = ocfs2_extend_rotate_transaction(handle, subtree_index,
3386					jbd2_handle_buffer_credits(handle),
3387					right_path);
3388		if (ret) {
3389			mlog_errno(ret);
3390			goto out;
3391		}
3392
3393		root_bh = left_path->p_node[subtree_index].bh;
3394		BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
3395
3396		ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
3397						   subtree_index);
3398		if (ret) {
3399			mlog_errno(ret);
3400			goto out;
3401		}
3402
3403		for (i = subtree_index + 1;
3404		     i < path_num_items(right_path); i++) {
3405			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3406							   right_path, i);
3407			if (ret) {
3408				mlog_errno(ret);
3409				goto out;
3410			}
3411
3412			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3413							   left_path, i);
3414			if (ret) {
3415				mlog_errno(ret);
3416				goto out;
3417			}
3418		}
3419
3420	} else {
3421		BUG_ON(index == le16_to_cpu(el->l_next_free_rec) - 1);
3422		right_rec = &el->l_recs[index + 1];
3423	}
3424
3425	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, left_path,
3426					   path_num_items(left_path) - 1);
3427	if (ret) {
3428		mlog_errno(ret);
3429		goto out;
3430	}
3431
3432	le16_add_cpu(&left_rec->e_leaf_clusters, -split_clusters);
3433
3434	le32_add_cpu(&right_rec->e_cpos, -split_clusters);
3435	le64_add_cpu(&right_rec->e_blkno,
3436		     -ocfs2_clusters_to_blocks(ocfs2_metadata_cache_get_super(et->et_ci),
3437					       split_clusters));
3438	le16_add_cpu(&right_rec->e_leaf_clusters, split_clusters);
3439
3440	ocfs2_cleanup_merge(el, index);
3441
3442	ocfs2_journal_dirty(handle, bh);
3443	if (right_path) {
3444		ocfs2_journal_dirty(handle, path_leaf_bh(right_path));
3445		ocfs2_complete_edge_insert(handle, left_path, right_path,
3446					   subtree_index);
3447	}
3448out:
3449	ocfs2_free_path(right_path);
 
3450	return ret;
3451}
3452
3453static int ocfs2_get_left_path(struct ocfs2_extent_tree *et,
3454			       struct ocfs2_path *right_path,
3455			       struct ocfs2_path **ret_left_path)
3456{
3457	int ret;
3458	u32 left_cpos;
3459	struct ocfs2_path *left_path = NULL;
3460
3461	*ret_left_path = NULL;
3462
3463	/* This function shouldn't be called for non-trees. */
3464	BUG_ON(right_path->p_tree_depth == 0);
3465
3466	ret = ocfs2_find_cpos_for_left_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
3467					    right_path, &left_cpos);
3468	if (ret) {
3469		mlog_errno(ret);
3470		goto out;
3471	}
3472
3473	/* This function shouldn't be called for the leftmost leaf. */
3474	BUG_ON(left_cpos == 0);
3475
3476	left_path = ocfs2_new_path_from_path(right_path);
3477	if (!left_path) {
3478		ret = -ENOMEM;
3479		mlog_errno(ret);
3480		goto out;
3481	}
3482
3483	ret = ocfs2_find_path(et->et_ci, left_path, left_cpos);
3484	if (ret) {
3485		mlog_errno(ret);
3486		goto out;
3487	}
3488
3489	*ret_left_path = left_path;
3490out:
3491	if (ret)
3492		ocfs2_free_path(left_path);
3493	return ret;
3494}
3495
3496/*
3497 * Remove split_rec clusters from the record at index and merge them
3498 * onto the tail of the record "before" it.
3499 * For index > 0, the "before" means the extent rec at index - 1.
3500 *
3501 * For index == 0, the "before" means the last record of the previous
3502 * extent block. And there is also a situation that we may need to
3503 * remove the rightmost leaf extent block in the right_path and change
3504 * the right path to indicate the new rightmost path.
3505 */
3506static int ocfs2_merge_rec_left(struct ocfs2_path *right_path,
3507				handle_t *handle,
3508				struct ocfs2_extent_tree *et,
3509				struct ocfs2_extent_rec *split_rec,
3510				struct ocfs2_cached_dealloc_ctxt *dealloc,
3511				int index)
3512{
3513	int ret, i, subtree_index = 0, has_empty_extent = 0;
3514	unsigned int split_clusters = le16_to_cpu(split_rec->e_leaf_clusters);
3515	struct ocfs2_extent_rec *left_rec;
3516	struct ocfs2_extent_rec *right_rec;
3517	struct ocfs2_extent_list *el = path_leaf_el(right_path);
3518	struct buffer_head *bh = path_leaf_bh(right_path);
3519	struct buffer_head *root_bh = NULL;
3520	struct ocfs2_path *left_path = NULL;
3521	struct ocfs2_extent_list *left_el;
3522
3523	BUG_ON(index < 0);
3524
3525	right_rec = &el->l_recs[index];
3526	if (index == 0) {
3527		/* we meet with a cross extent block merge. */
3528		ret = ocfs2_get_left_path(et, right_path, &left_path);
3529		if (ret) {
3530			mlog_errno(ret);
3531			return ret;
3532		}
3533
3534		left_el = path_leaf_el(left_path);
3535		BUG_ON(le16_to_cpu(left_el->l_next_free_rec) !=
3536		       le16_to_cpu(left_el->l_count));
3537
3538		left_rec = &left_el->l_recs[
3539				le16_to_cpu(left_el->l_next_free_rec) - 1];
3540		BUG_ON(le32_to_cpu(left_rec->e_cpos) +
3541		       le16_to_cpu(left_rec->e_leaf_clusters) !=
3542		       le32_to_cpu(split_rec->e_cpos));
3543
3544		subtree_index = ocfs2_find_subtree_root(et, left_path,
3545							right_path);
3546
3547		ret = ocfs2_extend_rotate_transaction(handle, subtree_index,
3548					jbd2_handle_buffer_credits(handle),
3549					left_path);
3550		if (ret) {
3551			mlog_errno(ret);
3552			goto out;
3553		}
3554
3555		root_bh = left_path->p_node[subtree_index].bh;
3556		BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
3557
3558		ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
3559						   subtree_index);
3560		if (ret) {
3561			mlog_errno(ret);
3562			goto out;
3563		}
3564
3565		for (i = subtree_index + 1;
3566		     i < path_num_items(right_path); i++) {
3567			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3568							   right_path, i);
3569			if (ret) {
3570				mlog_errno(ret);
3571				goto out;
3572			}
3573
3574			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3575							   left_path, i);
3576			if (ret) {
3577				mlog_errno(ret);
3578				goto out;
3579			}
3580		}
3581	} else {
3582		left_rec = &el->l_recs[index - 1];
3583		if (ocfs2_is_empty_extent(&el->l_recs[0]))
3584			has_empty_extent = 1;
3585	}
3586
3587	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
3588					   path_num_items(right_path) - 1);
3589	if (ret) {
3590		mlog_errno(ret);
3591		goto out;
3592	}
3593
3594	if (has_empty_extent && index == 1) {
3595		/*
3596		 * The easy case - we can just plop the record right in.
3597		 */
3598		*left_rec = *split_rec;
 
 
3599	} else
3600		le16_add_cpu(&left_rec->e_leaf_clusters, split_clusters);
3601
3602	le32_add_cpu(&right_rec->e_cpos, split_clusters);
3603	le64_add_cpu(&right_rec->e_blkno,
3604		     ocfs2_clusters_to_blocks(ocfs2_metadata_cache_get_super(et->et_ci),
3605					      split_clusters));
3606	le16_add_cpu(&right_rec->e_leaf_clusters, -split_clusters);
3607
3608	ocfs2_cleanup_merge(el, index);
3609
3610	ocfs2_journal_dirty(handle, bh);
3611	if (left_path) {
3612		ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
3613
3614		/*
3615		 * In the situation that the right_rec is empty and the extent
3616		 * block is empty also,  ocfs2_complete_edge_insert can't handle
3617		 * it and we need to delete the right extent block.
3618		 */
3619		if (le16_to_cpu(right_rec->e_leaf_clusters) == 0 &&
3620		    le16_to_cpu(el->l_next_free_rec) == 1) {
3621			/* extend credit for ocfs2_remove_rightmost_path */
3622			ret = ocfs2_extend_rotate_transaction(handle, 0,
3623					jbd2_handle_buffer_credits(handle),
3624					right_path);
3625			if (ret) {
3626				mlog_errno(ret);
3627				goto out;
3628			}
3629
3630			ret = ocfs2_remove_rightmost_path(handle, et,
3631							  right_path,
3632							  dealloc);
3633			if (ret) {
3634				mlog_errno(ret);
3635				goto out;
3636			}
3637
3638			/* Now the rightmost extent block has been deleted.
3639			 * So we use the new rightmost path.
3640			 */
3641			ocfs2_mv_path(right_path, left_path);
3642			left_path = NULL;
3643		} else
3644			ocfs2_complete_edge_insert(handle, left_path,
3645						   right_path, subtree_index);
3646	}
3647out:
3648	ocfs2_free_path(left_path);
 
3649	return ret;
3650}
3651
3652static int ocfs2_try_to_merge_extent(handle_t *handle,
3653				     struct ocfs2_extent_tree *et,
3654				     struct ocfs2_path *path,
3655				     int split_index,
3656				     struct ocfs2_extent_rec *split_rec,
3657				     struct ocfs2_cached_dealloc_ctxt *dealloc,
3658				     struct ocfs2_merge_ctxt *ctxt)
3659{
3660	int ret = 0;
3661	struct ocfs2_extent_list *el = path_leaf_el(path);
3662	struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
3663
3664	BUG_ON(ctxt->c_contig_type == CONTIG_NONE);
3665
3666	if (ctxt->c_split_covers_rec && ctxt->c_has_empty_extent) {
3667		/* extend credit for ocfs2_remove_rightmost_path */
3668		ret = ocfs2_extend_rotate_transaction(handle, 0,
3669				jbd2_handle_buffer_credits(handle),
3670				path);
3671		if (ret) {
3672			mlog_errno(ret);
3673			goto out;
3674		}
3675		/*
3676		 * The merge code will need to create an empty
3677		 * extent to take the place of the newly
3678		 * emptied slot. Remove any pre-existing empty
3679		 * extents - having more than one in a leaf is
3680		 * illegal.
3681		 */
3682		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
3683		if (ret) {
3684			mlog_errno(ret);
3685			goto out;
3686		}
3687		split_index--;
3688		rec = &el->l_recs[split_index];
3689	}
3690
3691	if (ctxt->c_contig_type == CONTIG_LEFTRIGHT) {
3692		/*
3693		 * Left-right contig implies this.
3694		 */
3695		BUG_ON(!ctxt->c_split_covers_rec);
3696
3697		/*
3698		 * Since the leftright insert always covers the entire
3699		 * extent, this call will delete the insert record
3700		 * entirely, resulting in an empty extent record added to
3701		 * the extent block.
3702		 *
3703		 * Since the adding of an empty extent shifts
3704		 * everything back to the right, there's no need to
3705		 * update split_index here.
3706		 *
3707		 * When the split_index is zero, we need to merge it to the
3708		 * prevoius extent block. It is more efficient and easier
3709		 * if we do merge_right first and merge_left later.
3710		 */
3711		ret = ocfs2_merge_rec_right(path, handle, et, split_rec,
3712					    split_index);
3713		if (ret) {
3714			mlog_errno(ret);
3715			goto out;
3716		}
3717
3718		/*
3719		 * We can only get this from logic error above.
3720		 */
3721		BUG_ON(!ocfs2_is_empty_extent(&el->l_recs[0]));
3722
3723		/* extend credit for ocfs2_remove_rightmost_path */
3724		ret = ocfs2_extend_rotate_transaction(handle, 0,
3725					jbd2_handle_buffer_credits(handle),
3726					path);
3727		if (ret) {
3728			mlog_errno(ret);
3729			goto out;
3730		}
3731
3732		/* The merge left us with an empty extent, remove it. */
3733		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
3734		if (ret) {
3735			mlog_errno(ret);
3736			goto out;
3737		}
3738
3739		rec = &el->l_recs[split_index];
3740
3741		/*
3742		 * Note that we don't pass split_rec here on purpose -
3743		 * we've merged it into the rec already.
3744		 */
3745		ret = ocfs2_merge_rec_left(path, handle, et, rec,
3746					   dealloc, split_index);
3747
3748		if (ret) {
3749			mlog_errno(ret);
3750			goto out;
3751		}
3752
3753		/* extend credit for ocfs2_remove_rightmost_path */
3754		ret = ocfs2_extend_rotate_transaction(handle, 0,
3755				jbd2_handle_buffer_credits(handle),
3756				path);
3757		if (ret) {
3758			mlog_errno(ret);
3759			goto out;
3760		}
3761
3762		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
3763		/*
3764		 * Error from this last rotate is not critical, so
3765		 * print but don't bubble it up.
3766		 */
3767		if (ret)
3768			mlog_errno(ret);
3769		ret = 0;
3770	} else {
3771		/*
3772		 * Merge a record to the left or right.
3773		 *
3774		 * 'contig_type' is relative to the existing record,
3775		 * so for example, if we're "right contig", it's to
3776		 * the record on the left (hence the left merge).
3777		 */
3778		if (ctxt->c_contig_type == CONTIG_RIGHT) {
3779			ret = ocfs2_merge_rec_left(path, handle, et,
3780						   split_rec, dealloc,
3781						   split_index);
3782			if (ret) {
3783				mlog_errno(ret);
3784				goto out;
3785			}
3786		} else {
3787			ret = ocfs2_merge_rec_right(path, handle,
3788						    et, split_rec,
3789						    split_index);
3790			if (ret) {
3791				mlog_errno(ret);
3792				goto out;
3793			}
3794		}
3795
3796		if (ctxt->c_split_covers_rec) {
3797			/* extend credit for ocfs2_remove_rightmost_path */
3798			ret = ocfs2_extend_rotate_transaction(handle, 0,
3799					jbd2_handle_buffer_credits(handle),
3800					path);
3801			if (ret) {
3802				mlog_errno(ret);
3803				ret = 0;
3804				goto out;
3805			}
3806
3807			/*
3808			 * The merge may have left an empty extent in
3809			 * our leaf. Try to rotate it away.
3810			 */
3811			ret = ocfs2_rotate_tree_left(handle, et, path,
3812						     dealloc);
3813			if (ret)
3814				mlog_errno(ret);
3815			ret = 0;
3816		}
3817	}
3818
3819out:
3820	return ret;
3821}
3822
3823static void ocfs2_subtract_from_rec(struct super_block *sb,
3824				    enum ocfs2_split_type split,
3825				    struct ocfs2_extent_rec *rec,
3826				    struct ocfs2_extent_rec *split_rec)
3827{
3828	u64 len_blocks;
3829
3830	len_blocks = ocfs2_clusters_to_blocks(sb,
3831				le16_to_cpu(split_rec->e_leaf_clusters));
3832
3833	if (split == SPLIT_LEFT) {
3834		/*
3835		 * Region is on the left edge of the existing
3836		 * record.
3837		 */
3838		le32_add_cpu(&rec->e_cpos,
3839			     le16_to_cpu(split_rec->e_leaf_clusters));
3840		le64_add_cpu(&rec->e_blkno, len_blocks);
3841		le16_add_cpu(&rec->e_leaf_clusters,
3842			     -le16_to_cpu(split_rec->e_leaf_clusters));
3843	} else {
3844		/*
3845		 * Region is on the right edge of the existing
3846		 * record.
3847		 */
3848		le16_add_cpu(&rec->e_leaf_clusters,
3849			     -le16_to_cpu(split_rec->e_leaf_clusters));
3850	}
3851}
3852
3853/*
3854 * Do the final bits of extent record insertion at the target leaf
3855 * list. If this leaf is part of an allocation tree, it is assumed
3856 * that the tree above has been prepared.
3857 */
3858static void ocfs2_insert_at_leaf(struct ocfs2_extent_tree *et,
3859				 struct ocfs2_extent_rec *insert_rec,
3860				 struct ocfs2_extent_list *el,
3861				 struct ocfs2_insert_type *insert)
3862{
3863	int i = insert->ins_contig_index;
3864	unsigned int range;
3865	struct ocfs2_extent_rec *rec;
3866
3867	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
3868
3869	if (insert->ins_split != SPLIT_NONE) {
3870		i = ocfs2_search_extent_list(el, le32_to_cpu(insert_rec->e_cpos));
3871		BUG_ON(i == -1);
3872		rec = &el->l_recs[i];
3873		ocfs2_subtract_from_rec(ocfs2_metadata_cache_get_super(et->et_ci),
3874					insert->ins_split, rec,
3875					insert_rec);
3876		goto rotate;
3877	}
3878
3879	/*
3880	 * Contiguous insert - either left or right.
3881	 */
3882	if (insert->ins_contig != CONTIG_NONE) {
3883		rec = &el->l_recs[i];
3884		if (insert->ins_contig == CONTIG_LEFT) {
3885			rec->e_blkno = insert_rec->e_blkno;
3886			rec->e_cpos = insert_rec->e_cpos;
3887		}
3888		le16_add_cpu(&rec->e_leaf_clusters,
3889			     le16_to_cpu(insert_rec->e_leaf_clusters));
3890		return;
3891	}
3892
3893	/*
3894	 * Handle insert into an empty leaf.
3895	 */
3896	if (le16_to_cpu(el->l_next_free_rec) == 0 ||
3897	    ((le16_to_cpu(el->l_next_free_rec) == 1) &&
3898	     ocfs2_is_empty_extent(&el->l_recs[0]))) {
3899		el->l_recs[0] = *insert_rec;
3900		el->l_next_free_rec = cpu_to_le16(1);
3901		return;
3902	}
3903
3904	/*
3905	 * Appending insert.
3906	 */
3907	if (insert->ins_appending == APPEND_TAIL) {
3908		i = le16_to_cpu(el->l_next_free_rec) - 1;
3909		rec = &el->l_recs[i];
3910		range = le32_to_cpu(rec->e_cpos)
3911			+ le16_to_cpu(rec->e_leaf_clusters);
3912		BUG_ON(le32_to_cpu(insert_rec->e_cpos) < range);
3913
3914		mlog_bug_on_msg(le16_to_cpu(el->l_next_free_rec) >=
3915				le16_to_cpu(el->l_count),
3916				"owner %llu, depth %u, count %u, next free %u, "
3917				"rec.cpos %u, rec.clusters %u, "
3918				"insert.cpos %u, insert.clusters %u\n",
3919				ocfs2_metadata_cache_owner(et->et_ci),
3920				le16_to_cpu(el->l_tree_depth),
3921				le16_to_cpu(el->l_count),
3922				le16_to_cpu(el->l_next_free_rec),
3923				le32_to_cpu(el->l_recs[i].e_cpos),
3924				le16_to_cpu(el->l_recs[i].e_leaf_clusters),
3925				le32_to_cpu(insert_rec->e_cpos),
3926				le16_to_cpu(insert_rec->e_leaf_clusters));
3927		i++;
3928		el->l_recs[i] = *insert_rec;
3929		le16_add_cpu(&el->l_next_free_rec, 1);
3930		return;
3931	}
3932
3933rotate:
3934	/*
3935	 * Ok, we have to rotate.
3936	 *
3937	 * At this point, it is safe to assume that inserting into an
3938	 * empty leaf and appending to a leaf have both been handled
3939	 * above.
3940	 *
3941	 * This leaf needs to have space, either by the empty 1st
3942	 * extent record, or by virtue of an l_next_free_rec < l_count.
3943	 */
3944	ocfs2_rotate_leaf(el, insert_rec);
3945}
3946
3947static void ocfs2_adjust_rightmost_records(handle_t *handle,
3948					   struct ocfs2_extent_tree *et,
3949					   struct ocfs2_path *path,
3950					   struct ocfs2_extent_rec *insert_rec)
3951{
3952	int i, next_free;
3953	struct buffer_head *bh;
3954	struct ocfs2_extent_list *el;
3955	struct ocfs2_extent_rec *rec;
3956
3957	/*
3958	 * Update everything except the leaf block.
3959	 */
3960	for (i = 0; i < path->p_tree_depth; i++) {
3961		bh = path->p_node[i].bh;
3962		el = path->p_node[i].el;
3963
3964		next_free = le16_to_cpu(el->l_next_free_rec);
3965		if (next_free == 0) {
3966			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
3967				    "Owner %llu has a bad extent list\n",
3968				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci));
 
3969			return;
3970		}
3971
3972		rec = &el->l_recs[next_free - 1];
3973
3974		rec->e_int_clusters = insert_rec->e_cpos;
3975		le32_add_cpu(&rec->e_int_clusters,
3976			     le16_to_cpu(insert_rec->e_leaf_clusters));
3977		le32_add_cpu(&rec->e_int_clusters,
3978			     -le32_to_cpu(rec->e_cpos));
3979
3980		ocfs2_journal_dirty(handle, bh);
3981	}
3982}
3983
3984static int ocfs2_append_rec_to_path(handle_t *handle,
3985				    struct ocfs2_extent_tree *et,
3986				    struct ocfs2_extent_rec *insert_rec,
3987				    struct ocfs2_path *right_path,
3988				    struct ocfs2_path **ret_left_path)
3989{
3990	int ret, next_free;
3991	struct ocfs2_extent_list *el;
3992	struct ocfs2_path *left_path = NULL;
3993
3994	*ret_left_path = NULL;
3995
3996	/*
3997	 * This shouldn't happen for non-trees. The extent rec cluster
3998	 * count manipulation below only works for interior nodes.
3999	 */
4000	BUG_ON(right_path->p_tree_depth == 0);
4001
4002	/*
4003	 * If our appending insert is at the leftmost edge of a leaf,
4004	 * then we might need to update the rightmost records of the
4005	 * neighboring path.
4006	 */
4007	el = path_leaf_el(right_path);
4008	next_free = le16_to_cpu(el->l_next_free_rec);
4009	if (next_free == 0 ||
4010	    (next_free == 1 && ocfs2_is_empty_extent(&el->l_recs[0]))) {
4011		u32 left_cpos;
4012
4013		ret = ocfs2_find_cpos_for_left_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
4014						    right_path, &left_cpos);
4015		if (ret) {
4016			mlog_errno(ret);
4017			goto out;
4018		}
4019
4020		trace_ocfs2_append_rec_to_path(
4021			(unsigned long long)
4022			ocfs2_metadata_cache_owner(et->et_ci),
4023			le32_to_cpu(insert_rec->e_cpos),
4024			left_cpos);
4025
4026		/*
4027		 * No need to worry if the append is already in the
4028		 * leftmost leaf.
4029		 */
4030		if (left_cpos) {
4031			left_path = ocfs2_new_path_from_path(right_path);
4032			if (!left_path) {
4033				ret = -ENOMEM;
4034				mlog_errno(ret);
4035				goto out;
4036			}
4037
4038			ret = ocfs2_find_path(et->et_ci, left_path,
4039					      left_cpos);
4040			if (ret) {
4041				mlog_errno(ret);
4042				goto out;
4043			}
4044
4045			/*
4046			 * ocfs2_insert_path() will pass the left_path to the
4047			 * journal for us.
4048			 */
4049		}
4050	}
4051
4052	ret = ocfs2_journal_access_path(et->et_ci, handle, right_path);
4053	if (ret) {
4054		mlog_errno(ret);
4055		goto out;
4056	}
4057
4058	ocfs2_adjust_rightmost_records(handle, et, right_path, insert_rec);
4059
4060	*ret_left_path = left_path;
4061	ret = 0;
4062out:
4063	if (ret != 0)
4064		ocfs2_free_path(left_path);
4065
4066	return ret;
4067}
4068
4069static void ocfs2_split_record(struct ocfs2_extent_tree *et,
4070			       struct ocfs2_path *left_path,
4071			       struct ocfs2_path *right_path,
4072			       struct ocfs2_extent_rec *split_rec,
4073			       enum ocfs2_split_type split)
4074{
4075	int index;
4076	u32 cpos = le32_to_cpu(split_rec->e_cpos);
4077	struct ocfs2_extent_list *left_el = NULL, *right_el, *insert_el, *el;
4078	struct ocfs2_extent_rec *rec, *tmprec;
4079
4080	right_el = path_leaf_el(right_path);
4081	if (left_path)
4082		left_el = path_leaf_el(left_path);
4083
4084	el = right_el;
4085	insert_el = right_el;
4086	index = ocfs2_search_extent_list(el, cpos);
4087	if (index != -1) {
4088		if (index == 0 && left_path) {
4089			BUG_ON(ocfs2_is_empty_extent(&el->l_recs[0]));
4090
4091			/*
4092			 * This typically means that the record
4093			 * started in the left path but moved to the
4094			 * right as a result of rotation. We either
4095			 * move the existing record to the left, or we
4096			 * do the later insert there.
4097			 *
4098			 * In this case, the left path should always
4099			 * exist as the rotate code will have passed
4100			 * it back for a post-insert update.
4101			 */
4102
4103			if (split == SPLIT_LEFT) {
4104				/*
4105				 * It's a left split. Since we know
4106				 * that the rotate code gave us an
4107				 * empty extent in the left path, we
4108				 * can just do the insert there.
4109				 */
4110				insert_el = left_el;
4111			} else {
4112				/*
4113				 * Right split - we have to move the
4114				 * existing record over to the left
4115				 * leaf. The insert will be into the
4116				 * newly created empty extent in the
4117				 * right leaf.
4118				 */
4119				tmprec = &right_el->l_recs[index];
4120				ocfs2_rotate_leaf(left_el, tmprec);
4121				el = left_el;
4122
4123				memset(tmprec, 0, sizeof(*tmprec));
4124				index = ocfs2_search_extent_list(left_el, cpos);
4125				BUG_ON(index == -1);
4126			}
4127		}
4128	} else {
4129		BUG_ON(!left_path);
4130		BUG_ON(!ocfs2_is_empty_extent(&left_el->l_recs[0]));
4131		/*
4132		 * Left path is easy - we can just allow the insert to
4133		 * happen.
4134		 */
4135		el = left_el;
4136		insert_el = left_el;
4137		index = ocfs2_search_extent_list(el, cpos);
4138		BUG_ON(index == -1);
4139	}
4140
4141	rec = &el->l_recs[index];
4142	ocfs2_subtract_from_rec(ocfs2_metadata_cache_get_super(et->et_ci),
4143				split, rec, split_rec);
4144	ocfs2_rotate_leaf(insert_el, split_rec);
4145}
4146
4147/*
4148 * This function only does inserts on an allocation b-tree. For tree
4149 * depth = 0, ocfs2_insert_at_leaf() is called directly.
4150 *
4151 * right_path is the path we want to do the actual insert
4152 * in. left_path should only be passed in if we need to update that
4153 * portion of the tree after an edge insert.
4154 */
4155static int ocfs2_insert_path(handle_t *handle,
4156			     struct ocfs2_extent_tree *et,
4157			     struct ocfs2_path *left_path,
4158			     struct ocfs2_path *right_path,
4159			     struct ocfs2_extent_rec *insert_rec,
4160			     struct ocfs2_insert_type *insert)
4161{
4162	int ret, subtree_index;
4163	struct buffer_head *leaf_bh = path_leaf_bh(right_path);
4164
4165	if (left_path) {
4166		/*
4167		 * There's a chance that left_path got passed back to
4168		 * us without being accounted for in the
4169		 * journal. Extend our transaction here to be sure we
4170		 * can change those blocks.
4171		 */
4172		ret = ocfs2_extend_trans(handle, left_path->p_tree_depth);
4173		if (ret < 0) {
4174			mlog_errno(ret);
4175			goto out;
4176		}
4177
4178		ret = ocfs2_journal_access_path(et->et_ci, handle, left_path);
4179		if (ret < 0) {
4180			mlog_errno(ret);
4181			goto out;
4182		}
4183	}
4184
4185	/*
4186	 * Pass both paths to the journal. The majority of inserts
4187	 * will be touching all components anyway.
4188	 */
4189	ret = ocfs2_journal_access_path(et->et_ci, handle, right_path);
4190	if (ret < 0) {
4191		mlog_errno(ret);
4192		goto out;
4193	}
4194
4195	if (insert->ins_split != SPLIT_NONE) {
4196		/*
4197		 * We could call ocfs2_insert_at_leaf() for some types
4198		 * of splits, but it's easier to just let one separate
4199		 * function sort it all out.
4200		 */
4201		ocfs2_split_record(et, left_path, right_path,
4202				   insert_rec, insert->ins_split);
4203
4204		/*
4205		 * Split might have modified either leaf and we don't
4206		 * have a guarantee that the later edge insert will
4207		 * dirty this for us.
4208		 */
4209		if (left_path)
4210			ocfs2_journal_dirty(handle,
4211					    path_leaf_bh(left_path));
4212	} else
4213		ocfs2_insert_at_leaf(et, insert_rec, path_leaf_el(right_path),
4214				     insert);
4215
4216	ocfs2_journal_dirty(handle, leaf_bh);
4217
4218	if (left_path) {
4219		/*
4220		 * The rotate code has indicated that we need to fix
4221		 * up portions of the tree after the insert.
4222		 *
4223		 * XXX: Should we extend the transaction here?
4224		 */
4225		subtree_index = ocfs2_find_subtree_root(et, left_path,
4226							right_path);
4227		ocfs2_complete_edge_insert(handle, left_path, right_path,
4228					   subtree_index);
4229	}
4230
4231	ret = 0;
4232out:
4233	return ret;
4234}
4235
4236static int ocfs2_do_insert_extent(handle_t *handle,
4237				  struct ocfs2_extent_tree *et,
4238				  struct ocfs2_extent_rec *insert_rec,
4239				  struct ocfs2_insert_type *type)
4240{
4241	int ret, rotate = 0;
4242	u32 cpos;
4243	struct ocfs2_path *right_path = NULL;
4244	struct ocfs2_path *left_path = NULL;
4245	struct ocfs2_extent_list *el;
4246
4247	el = et->et_root_el;
4248
4249	ret = ocfs2_et_root_journal_access(handle, et,
4250					   OCFS2_JOURNAL_ACCESS_WRITE);
4251	if (ret) {
4252		mlog_errno(ret);
4253		goto out;
4254	}
4255
4256	if (le16_to_cpu(el->l_tree_depth) == 0) {
4257		ocfs2_insert_at_leaf(et, insert_rec, el, type);
4258		goto out_update_clusters;
4259	}
4260
4261	right_path = ocfs2_new_path_from_et(et);
4262	if (!right_path) {
4263		ret = -ENOMEM;
4264		mlog_errno(ret);
4265		goto out;
4266	}
4267
4268	/*
4269	 * Determine the path to start with. Rotations need the
4270	 * rightmost path, everything else can go directly to the
4271	 * target leaf.
4272	 */
4273	cpos = le32_to_cpu(insert_rec->e_cpos);
4274	if (type->ins_appending == APPEND_NONE &&
4275	    type->ins_contig == CONTIG_NONE) {
4276		rotate = 1;
4277		cpos = UINT_MAX;
4278	}
4279
4280	ret = ocfs2_find_path(et->et_ci, right_path, cpos);
4281	if (ret) {
4282		mlog_errno(ret);
4283		goto out;
4284	}
4285
4286	/*
4287	 * Rotations and appends need special treatment - they modify
4288	 * parts of the tree's above them.
4289	 *
4290	 * Both might pass back a path immediate to the left of the
4291	 * one being inserted to. This will be cause
4292	 * ocfs2_insert_path() to modify the rightmost records of
4293	 * left_path to account for an edge insert.
4294	 *
4295	 * XXX: When modifying this code, keep in mind that an insert
4296	 * can wind up skipping both of these two special cases...
4297	 */
4298	if (rotate) {
4299		ret = ocfs2_rotate_tree_right(handle, et, type->ins_split,
4300					      le32_to_cpu(insert_rec->e_cpos),
4301					      right_path, &left_path);
4302		if (ret) {
4303			mlog_errno(ret);
4304			goto out;
4305		}
4306
4307		/*
4308		 * ocfs2_rotate_tree_right() might have extended the
4309		 * transaction without re-journaling our tree root.
4310		 */
4311		ret = ocfs2_et_root_journal_access(handle, et,
4312						   OCFS2_JOURNAL_ACCESS_WRITE);
4313		if (ret) {
4314			mlog_errno(ret);
4315			goto out;
4316		}
4317	} else if (type->ins_appending == APPEND_TAIL
4318		   && type->ins_contig != CONTIG_LEFT) {
4319		ret = ocfs2_append_rec_to_path(handle, et, insert_rec,
4320					       right_path, &left_path);
4321		if (ret) {
4322			mlog_errno(ret);
4323			goto out;
4324		}
4325	}
4326
4327	ret = ocfs2_insert_path(handle, et, left_path, right_path,
4328				insert_rec, type);
4329	if (ret) {
4330		mlog_errno(ret);
4331		goto out;
4332	}
4333
4334out_update_clusters:
4335	if (type->ins_split == SPLIT_NONE)
4336		ocfs2_et_update_clusters(et,
4337					 le16_to_cpu(insert_rec->e_leaf_clusters));
4338
4339	ocfs2_journal_dirty(handle, et->et_root_bh);
4340
4341out:
4342	ocfs2_free_path(left_path);
4343	ocfs2_free_path(right_path);
4344
4345	return ret;
4346}
4347
4348static int ocfs2_figure_merge_contig_type(struct ocfs2_extent_tree *et,
 
4349			       struct ocfs2_path *path,
4350			       struct ocfs2_extent_list *el, int index,
4351			       struct ocfs2_extent_rec *split_rec,
4352			       struct ocfs2_merge_ctxt *ctxt)
4353{
4354	int status = 0;
4355	enum ocfs2_contig_type ret = CONTIG_NONE;
4356	u32 left_cpos, right_cpos;
4357	struct ocfs2_extent_rec *rec = NULL;
4358	struct ocfs2_extent_list *new_el;
4359	struct ocfs2_path *left_path = NULL, *right_path = NULL;
4360	struct buffer_head *bh;
4361	struct ocfs2_extent_block *eb;
4362	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
4363
4364	if (index > 0) {
4365		rec = &el->l_recs[index - 1];
4366	} else if (path->p_tree_depth > 0) {
4367		status = ocfs2_find_cpos_for_left_leaf(sb, path, &left_cpos);
4368		if (status)
4369			goto exit;
4370
4371		if (left_cpos != 0) {
4372			left_path = ocfs2_new_path_from_path(path);
4373			if (!left_path) {
4374				status = -ENOMEM;
4375				mlog_errno(status);
4376				goto exit;
4377			}
4378
4379			status = ocfs2_find_path(et->et_ci, left_path,
4380						 left_cpos);
4381			if (status)
4382				goto free_left_path;
4383
4384			new_el = path_leaf_el(left_path);
4385
4386			if (le16_to_cpu(new_el->l_next_free_rec) !=
4387			    le16_to_cpu(new_el->l_count)) {
4388				bh = path_leaf_bh(left_path);
4389				eb = (struct ocfs2_extent_block *)bh->b_data;
4390				status = ocfs2_error(sb,
4391						"Extent block #%llu has an invalid l_next_free_rec of %d.  It should have matched the l_count of %d\n",
4392						(unsigned long long)le64_to_cpu(eb->h_blkno),
4393						le16_to_cpu(new_el->l_next_free_rec),
4394						le16_to_cpu(new_el->l_count));
4395				goto free_left_path;
 
 
 
 
4396			}
4397			rec = &new_el->l_recs[
4398				le16_to_cpu(new_el->l_next_free_rec) - 1];
4399		}
4400	}
4401
4402	/*
4403	 * We're careful to check for an empty extent record here -
4404	 * the merge code will know what to do if it sees one.
4405	 */
4406	if (rec) {
4407		if (index == 1 && ocfs2_is_empty_extent(rec)) {
4408			if (split_rec->e_cpos == el->l_recs[index].e_cpos)
4409				ret = CONTIG_RIGHT;
4410		} else {
4411			ret = ocfs2_et_extent_contig(et, rec, split_rec);
4412		}
4413	}
4414
4415	rec = NULL;
4416	if (index < (le16_to_cpu(el->l_next_free_rec) - 1))
4417		rec = &el->l_recs[index + 1];
4418	else if (le16_to_cpu(el->l_next_free_rec) == le16_to_cpu(el->l_count) &&
4419		 path->p_tree_depth > 0) {
4420		status = ocfs2_find_cpos_for_right_leaf(sb, path, &right_cpos);
4421		if (status)
4422			goto free_left_path;
4423
4424		if (right_cpos == 0)
4425			goto free_left_path;
4426
4427		right_path = ocfs2_new_path_from_path(path);
4428		if (!right_path) {
4429			status = -ENOMEM;
4430			mlog_errno(status);
4431			goto free_left_path;
4432		}
4433
4434		status = ocfs2_find_path(et->et_ci, right_path, right_cpos);
4435		if (status)
4436			goto free_right_path;
4437
4438		new_el = path_leaf_el(right_path);
4439		rec = &new_el->l_recs[0];
4440		if (ocfs2_is_empty_extent(rec)) {
4441			if (le16_to_cpu(new_el->l_next_free_rec) <= 1) {
4442				bh = path_leaf_bh(right_path);
4443				eb = (struct ocfs2_extent_block *)bh->b_data;
4444				status = ocfs2_error(sb,
4445						"Extent block #%llu has an invalid l_next_free_rec of %d\n",
4446						(unsigned long long)le64_to_cpu(eb->h_blkno),
4447						le16_to_cpu(new_el->l_next_free_rec));
4448				goto free_right_path;
 
 
4449			}
4450			rec = &new_el->l_recs[1];
4451		}
4452	}
4453
4454	if (rec) {
4455		enum ocfs2_contig_type contig_type;
4456
4457		contig_type = ocfs2_et_extent_contig(et, rec, split_rec);
4458
4459		if (contig_type == CONTIG_LEFT && ret == CONTIG_RIGHT)
4460			ret = CONTIG_LEFTRIGHT;
4461		else if (ret == CONTIG_NONE)
4462			ret = contig_type;
4463	}
4464
4465free_right_path:
4466	ocfs2_free_path(right_path);
4467free_left_path:
4468	ocfs2_free_path(left_path);
4469exit:
4470	if (status == 0)
4471		ctxt->c_contig_type = ret;
4472
4473	return status;
4474}
4475
4476static void ocfs2_figure_contig_type(struct ocfs2_extent_tree *et,
4477				     struct ocfs2_insert_type *insert,
4478				     struct ocfs2_extent_list *el,
4479				     struct ocfs2_extent_rec *insert_rec)
4480{
4481	int i;
4482	enum ocfs2_contig_type contig_type = CONTIG_NONE;
4483
4484	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
4485
4486	for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
4487		contig_type = ocfs2_et_extent_contig(et, &el->l_recs[i],
4488						     insert_rec);
4489		if (contig_type != CONTIG_NONE) {
4490			insert->ins_contig_index = i;
4491			break;
4492		}
4493	}
4494	insert->ins_contig = contig_type;
4495
4496	if (insert->ins_contig != CONTIG_NONE) {
4497		struct ocfs2_extent_rec *rec =
4498				&el->l_recs[insert->ins_contig_index];
4499		unsigned int len = le16_to_cpu(rec->e_leaf_clusters) +
4500				   le16_to_cpu(insert_rec->e_leaf_clusters);
4501
4502		/*
4503		 * Caller might want us to limit the size of extents, don't
4504		 * calculate contiguousness if we might exceed that limit.
4505		 */
4506		if (et->et_max_leaf_clusters &&
4507		    (len > et->et_max_leaf_clusters))
4508			insert->ins_contig = CONTIG_NONE;
4509	}
4510}
4511
4512/*
4513 * This should only be called against the righmost leaf extent list.
4514 *
4515 * ocfs2_figure_appending_type() will figure out whether we'll have to
4516 * insert at the tail of the rightmost leaf.
4517 *
4518 * This should also work against the root extent list for tree's with 0
4519 * depth. If we consider the root extent list to be the rightmost leaf node
4520 * then the logic here makes sense.
4521 */
4522static void ocfs2_figure_appending_type(struct ocfs2_insert_type *insert,
4523					struct ocfs2_extent_list *el,
4524					struct ocfs2_extent_rec *insert_rec)
4525{
4526	int i;
4527	u32 cpos = le32_to_cpu(insert_rec->e_cpos);
4528	struct ocfs2_extent_rec *rec;
4529
4530	insert->ins_appending = APPEND_NONE;
4531
4532	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
4533
4534	if (!el->l_next_free_rec)
4535		goto set_tail_append;
4536
4537	if (ocfs2_is_empty_extent(&el->l_recs[0])) {
4538		/* Were all records empty? */
4539		if (le16_to_cpu(el->l_next_free_rec) == 1)
4540			goto set_tail_append;
4541	}
4542
4543	i = le16_to_cpu(el->l_next_free_rec) - 1;
4544	rec = &el->l_recs[i];
4545
4546	if (cpos >=
4547	    (le32_to_cpu(rec->e_cpos) + le16_to_cpu(rec->e_leaf_clusters)))
4548		goto set_tail_append;
4549
4550	return;
4551
4552set_tail_append:
4553	insert->ins_appending = APPEND_TAIL;
4554}
4555
4556/*
4557 * Helper function called at the beginning of an insert.
4558 *
4559 * This computes a few things that are commonly used in the process of
4560 * inserting into the btree:
4561 *   - Whether the new extent is contiguous with an existing one.
4562 *   - The current tree depth.
4563 *   - Whether the insert is an appending one.
4564 *   - The total # of free records in the tree.
4565 *
4566 * All of the information is stored on the ocfs2_insert_type
4567 * structure.
4568 */
4569static int ocfs2_figure_insert_type(struct ocfs2_extent_tree *et,
4570				    struct buffer_head **last_eb_bh,
4571				    struct ocfs2_extent_rec *insert_rec,
4572				    int *free_records,
4573				    struct ocfs2_insert_type *insert)
4574{
4575	int ret;
4576	struct ocfs2_extent_block *eb;
4577	struct ocfs2_extent_list *el;
4578	struct ocfs2_path *path = NULL;
4579	struct buffer_head *bh = NULL;
4580
4581	insert->ins_split = SPLIT_NONE;
4582
4583	el = et->et_root_el;
4584	insert->ins_tree_depth = le16_to_cpu(el->l_tree_depth);
4585
4586	if (el->l_tree_depth) {
4587		/*
4588		 * If we have tree depth, we read in the
4589		 * rightmost extent block ahead of time as
4590		 * ocfs2_figure_insert_type() and ocfs2_add_branch()
4591		 * may want it later.
4592		 */
4593		ret = ocfs2_read_extent_block(et->et_ci,
4594					      ocfs2_et_get_last_eb_blk(et),
4595					      &bh);
4596		if (ret) {
4597			mlog_errno(ret);
4598			goto out;
4599		}
4600		eb = (struct ocfs2_extent_block *) bh->b_data;
4601		el = &eb->h_list;
4602	}
4603
4604	/*
4605	 * Unless we have a contiguous insert, we'll need to know if
4606	 * there is room left in our allocation tree for another
4607	 * extent record.
4608	 *
4609	 * XXX: This test is simplistic, we can search for empty
4610	 * extent records too.
4611	 */
4612	*free_records = le16_to_cpu(el->l_count) -
4613		le16_to_cpu(el->l_next_free_rec);
4614
4615	if (!insert->ins_tree_depth) {
4616		ocfs2_figure_contig_type(et, insert, el, insert_rec);
4617		ocfs2_figure_appending_type(insert, el, insert_rec);
4618		return 0;
4619	}
4620
4621	path = ocfs2_new_path_from_et(et);
4622	if (!path) {
4623		ret = -ENOMEM;
4624		mlog_errno(ret);
4625		goto out;
4626	}
4627
4628	/*
4629	 * In the case that we're inserting past what the tree
4630	 * currently accounts for, ocfs2_find_path() will return for
4631	 * us the rightmost tree path. This is accounted for below in
4632	 * the appending code.
4633	 */
4634	ret = ocfs2_find_path(et->et_ci, path, le32_to_cpu(insert_rec->e_cpos));
4635	if (ret) {
4636		mlog_errno(ret);
4637		goto out;
4638	}
4639
4640	el = path_leaf_el(path);
4641
4642	/*
4643	 * Now that we have the path, there's two things we want to determine:
4644	 * 1) Contiguousness (also set contig_index if this is so)
4645	 *
4646	 * 2) Are we doing an append? We can trivially break this up
4647         *     into two types of appends: simple record append, or a
4648         *     rotate inside the tail leaf.
4649	 */
4650	ocfs2_figure_contig_type(et, insert, el, insert_rec);
4651
4652	/*
4653	 * The insert code isn't quite ready to deal with all cases of
4654	 * left contiguousness. Specifically, if it's an insert into
4655	 * the 1st record in a leaf, it will require the adjustment of
4656	 * cluster count on the last record of the path directly to it's
4657	 * left. For now, just catch that case and fool the layers
4658	 * above us. This works just fine for tree_depth == 0, which
4659	 * is why we allow that above.
4660	 */
4661	if (insert->ins_contig == CONTIG_LEFT &&
4662	    insert->ins_contig_index == 0)
4663		insert->ins_contig = CONTIG_NONE;
4664
4665	/*
4666	 * Ok, so we can simply compare against last_eb to figure out
4667	 * whether the path doesn't exist. This will only happen in
4668	 * the case that we're doing a tail append, so maybe we can
4669	 * take advantage of that information somehow.
4670	 */
4671	if (ocfs2_et_get_last_eb_blk(et) ==
4672	    path_leaf_bh(path)->b_blocknr) {
4673		/*
4674		 * Ok, ocfs2_find_path() returned us the rightmost
4675		 * tree path. This might be an appending insert. There are
4676		 * two cases:
4677		 *    1) We're doing a true append at the tail:
4678		 *	-This might even be off the end of the leaf
4679		 *    2) We're "appending" by rotating in the tail
4680		 */
4681		ocfs2_figure_appending_type(insert, el, insert_rec);
4682	}
4683
4684out:
4685	ocfs2_free_path(path);
4686
4687	if (ret == 0)
4688		*last_eb_bh = bh;
4689	else
4690		brelse(bh);
4691	return ret;
4692}
4693
4694/*
4695 * Insert an extent into a btree.
4696 *
4697 * The caller needs to update the owning btree's cluster count.
4698 */
4699int ocfs2_insert_extent(handle_t *handle,
4700			struct ocfs2_extent_tree *et,
4701			u32 cpos,
4702			u64 start_blk,
4703			u32 new_clusters,
4704			u8 flags,
4705			struct ocfs2_alloc_context *meta_ac)
4706{
4707	int status;
4708	int free_records;
4709	struct buffer_head *last_eb_bh = NULL;
4710	struct ocfs2_insert_type insert = {0, };
4711	struct ocfs2_extent_rec rec;
4712
4713	trace_ocfs2_insert_extent_start(
4714		(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
4715		cpos, new_clusters);
4716
4717	memset(&rec, 0, sizeof(rec));
4718	rec.e_cpos = cpu_to_le32(cpos);
4719	rec.e_blkno = cpu_to_le64(start_blk);
4720	rec.e_leaf_clusters = cpu_to_le16(new_clusters);
4721	rec.e_flags = flags;
4722	status = ocfs2_et_insert_check(et, &rec);
4723	if (status) {
4724		mlog_errno(status);
4725		goto bail;
4726	}
4727
4728	status = ocfs2_figure_insert_type(et, &last_eb_bh, &rec,
4729					  &free_records, &insert);
4730	if (status < 0) {
4731		mlog_errno(status);
4732		goto bail;
4733	}
4734
4735	trace_ocfs2_insert_extent(insert.ins_appending, insert.ins_contig,
4736				  insert.ins_contig_index, free_records,
4737				  insert.ins_tree_depth);
4738
4739	if (insert.ins_contig == CONTIG_NONE && free_records == 0) {
4740		status = ocfs2_grow_tree(handle, et,
4741					 &insert.ins_tree_depth, &last_eb_bh,
4742					 meta_ac);
4743		if (status) {
4744			mlog_errno(status);
4745			goto bail;
4746		}
4747	}
4748
4749	/* Finally, we can add clusters. This might rotate the tree for us. */
4750	status = ocfs2_do_insert_extent(handle, et, &rec, &insert);
4751	if (status < 0)
4752		mlog_errno(status);
4753	else
4754		ocfs2_et_extent_map_insert(et, &rec);
4755
4756bail:
4757	brelse(last_eb_bh);
4758
4759	return status;
4760}
4761
4762/*
4763 * Allcate and add clusters into the extent b-tree.
4764 * The new clusters(clusters_to_add) will be inserted at logical_offset.
4765 * The extent b-tree's root is specified by et, and
4766 * it is not limited to the file storage. Any extent tree can use this
4767 * function if it implements the proper ocfs2_extent_tree.
4768 */
4769int ocfs2_add_clusters_in_btree(handle_t *handle,
4770				struct ocfs2_extent_tree *et,
4771				u32 *logical_offset,
4772				u32 clusters_to_add,
4773				int mark_unwritten,
4774				struct ocfs2_alloc_context *data_ac,
4775				struct ocfs2_alloc_context *meta_ac,
4776				enum ocfs2_alloc_restarted *reason_ret)
4777{
4778	int status = 0, err = 0;
4779	int need_free = 0;
4780	int free_extents;
4781	enum ocfs2_alloc_restarted reason = RESTART_NONE;
4782	u32 bit_off, num_bits;
4783	u64 block;
4784	u8 flags = 0;
4785	struct ocfs2_super *osb =
4786		OCFS2_SB(ocfs2_metadata_cache_get_super(et->et_ci));
4787
4788	BUG_ON(!clusters_to_add);
4789
4790	if (mark_unwritten)
4791		flags = OCFS2_EXT_UNWRITTEN;
4792
4793	free_extents = ocfs2_num_free_extents(et);
4794	if (free_extents < 0) {
4795		status = free_extents;
4796		mlog_errno(status);
4797		goto leave;
4798	}
4799
4800	/* there are two cases which could cause us to EAGAIN in the
4801	 * we-need-more-metadata case:
4802	 * 1) we haven't reserved *any*
4803	 * 2) we are so fragmented, we've needed to add metadata too
4804	 *    many times. */
4805	if (!free_extents && !meta_ac) {
4806		err = -1;
4807		status = -EAGAIN;
4808		reason = RESTART_META;
4809		goto leave;
4810	} else if ((!free_extents)
4811		   && (ocfs2_alloc_context_bits_left(meta_ac)
4812		       < ocfs2_extend_meta_needed(et->et_root_el))) {
4813		err = -2;
4814		status = -EAGAIN;
4815		reason = RESTART_META;
4816		goto leave;
4817	}
4818
4819	status = __ocfs2_claim_clusters(handle, data_ac, 1,
4820					clusters_to_add, &bit_off, &num_bits);
4821	if (status < 0) {
4822		if (status != -ENOSPC)
4823			mlog_errno(status);
4824		goto leave;
4825	}
4826
4827	BUG_ON(num_bits > clusters_to_add);
4828
4829	/* reserve our write early -- insert_extent may update the tree root */
4830	status = ocfs2_et_root_journal_access(handle, et,
4831					      OCFS2_JOURNAL_ACCESS_WRITE);
4832	if (status < 0) {
4833		mlog_errno(status);
4834		need_free = 1;
4835		goto bail;
4836	}
4837
4838	block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
4839	trace_ocfs2_add_clusters_in_btree(
4840	     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
4841	     bit_off, num_bits);
4842	status = ocfs2_insert_extent(handle, et, *logical_offset, block,
4843				     num_bits, flags, meta_ac);
4844	if (status < 0) {
4845		mlog_errno(status);
4846		need_free = 1;
4847		goto bail;
4848	}
4849
4850	ocfs2_journal_dirty(handle, et->et_root_bh);
4851
4852	clusters_to_add -= num_bits;
4853	*logical_offset += num_bits;
4854
4855	if (clusters_to_add) {
4856		err = clusters_to_add;
4857		status = -EAGAIN;
4858		reason = RESTART_TRANS;
4859	}
4860
4861bail:
4862	if (need_free) {
4863		if (data_ac->ac_which == OCFS2_AC_USE_LOCAL)
4864			ocfs2_free_local_alloc_bits(osb, handle, data_ac,
4865					bit_off, num_bits);
4866		else
4867			ocfs2_free_clusters(handle,
4868					data_ac->ac_inode,
4869					data_ac->ac_bh,
4870					ocfs2_clusters_to_blocks(osb->sb, bit_off),
4871					num_bits);
4872	}
4873
4874leave:
4875	if (reason_ret)
4876		*reason_ret = reason;
4877	trace_ocfs2_add_clusters_in_btree_ret(status, reason, err);
4878	return status;
4879}
4880
4881static void ocfs2_make_right_split_rec(struct super_block *sb,
4882				       struct ocfs2_extent_rec *split_rec,
4883				       u32 cpos,
4884				       struct ocfs2_extent_rec *rec)
4885{
4886	u32 rec_cpos = le32_to_cpu(rec->e_cpos);
4887	u32 rec_range = rec_cpos + le16_to_cpu(rec->e_leaf_clusters);
4888
4889	memset(split_rec, 0, sizeof(struct ocfs2_extent_rec));
4890
4891	split_rec->e_cpos = cpu_to_le32(cpos);
4892	split_rec->e_leaf_clusters = cpu_to_le16(rec_range - cpos);
4893
4894	split_rec->e_blkno = rec->e_blkno;
4895	le64_add_cpu(&split_rec->e_blkno,
4896		     ocfs2_clusters_to_blocks(sb, cpos - rec_cpos));
4897
4898	split_rec->e_flags = rec->e_flags;
4899}
4900
4901static int ocfs2_split_and_insert(handle_t *handle,
4902				  struct ocfs2_extent_tree *et,
4903				  struct ocfs2_path *path,
4904				  struct buffer_head **last_eb_bh,
4905				  int split_index,
4906				  struct ocfs2_extent_rec *orig_split_rec,
4907				  struct ocfs2_alloc_context *meta_ac)
4908{
4909	int ret = 0, depth;
4910	unsigned int insert_range, rec_range, do_leftright = 0;
4911	struct ocfs2_extent_rec tmprec;
4912	struct ocfs2_extent_list *rightmost_el;
4913	struct ocfs2_extent_rec rec;
4914	struct ocfs2_extent_rec split_rec = *orig_split_rec;
4915	struct ocfs2_insert_type insert;
4916	struct ocfs2_extent_block *eb;
4917
4918leftright:
4919	/*
4920	 * Store a copy of the record on the stack - it might move
4921	 * around as the tree is manipulated below.
4922	 */
4923	rec = path_leaf_el(path)->l_recs[split_index];
4924
4925	rightmost_el = et->et_root_el;
4926
4927	depth = le16_to_cpu(rightmost_el->l_tree_depth);
4928	if (depth) {
4929		BUG_ON(!(*last_eb_bh));
4930		eb = (struct ocfs2_extent_block *) (*last_eb_bh)->b_data;
4931		rightmost_el = &eb->h_list;
4932	}
4933
4934	if (le16_to_cpu(rightmost_el->l_next_free_rec) ==
4935	    le16_to_cpu(rightmost_el->l_count)) {
4936		ret = ocfs2_grow_tree(handle, et,
4937				      &depth, last_eb_bh, meta_ac);
4938		if (ret) {
4939			mlog_errno(ret);
4940			goto out;
4941		}
4942	}
4943
4944	memset(&insert, 0, sizeof(struct ocfs2_insert_type));
4945	insert.ins_appending = APPEND_NONE;
4946	insert.ins_contig = CONTIG_NONE;
4947	insert.ins_tree_depth = depth;
4948
4949	insert_range = le32_to_cpu(split_rec.e_cpos) +
4950		le16_to_cpu(split_rec.e_leaf_clusters);
4951	rec_range = le32_to_cpu(rec.e_cpos) +
4952		le16_to_cpu(rec.e_leaf_clusters);
4953
4954	if (split_rec.e_cpos == rec.e_cpos) {
4955		insert.ins_split = SPLIT_LEFT;
4956	} else if (insert_range == rec_range) {
4957		insert.ins_split = SPLIT_RIGHT;
4958	} else {
4959		/*
4960		 * Left/right split. We fake this as a right split
4961		 * first and then make a second pass as a left split.
4962		 */
4963		insert.ins_split = SPLIT_RIGHT;
4964
4965		ocfs2_make_right_split_rec(ocfs2_metadata_cache_get_super(et->et_ci),
4966					   &tmprec, insert_range, &rec);
4967
4968		split_rec = tmprec;
4969
4970		BUG_ON(do_leftright);
4971		do_leftright = 1;
4972	}
4973
4974	ret = ocfs2_do_insert_extent(handle, et, &split_rec, &insert);
4975	if (ret) {
4976		mlog_errno(ret);
4977		goto out;
4978	}
4979
4980	if (do_leftright == 1) {
4981		u32 cpos;
4982		struct ocfs2_extent_list *el;
4983
4984		do_leftright++;
4985		split_rec = *orig_split_rec;
4986
4987		ocfs2_reinit_path(path, 1);
4988
4989		cpos = le32_to_cpu(split_rec.e_cpos);
4990		ret = ocfs2_find_path(et->et_ci, path, cpos);
4991		if (ret) {
4992			mlog_errno(ret);
4993			goto out;
4994		}
4995
4996		el = path_leaf_el(path);
4997		split_index = ocfs2_search_extent_list(el, cpos);
4998		if (split_index == -1) {
4999			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5000				    "Owner %llu has an extent at cpos %u which can no longer be found\n",
5001				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5002				    cpos);
5003			ret = -EROFS;
5004			goto out;
5005		}
5006		goto leftright;
5007	}
5008out:
5009
5010	return ret;
5011}
5012
5013static int ocfs2_replace_extent_rec(handle_t *handle,
5014				    struct ocfs2_extent_tree *et,
5015				    struct ocfs2_path *path,
5016				    struct ocfs2_extent_list *el,
5017				    int split_index,
5018				    struct ocfs2_extent_rec *split_rec)
5019{
5020	int ret;
5021
5022	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, path,
5023					   path_num_items(path) - 1);
5024	if (ret) {
5025		mlog_errno(ret);
5026		goto out;
5027	}
5028
5029	el->l_recs[split_index] = *split_rec;
5030
5031	ocfs2_journal_dirty(handle, path_leaf_bh(path));
5032out:
5033	return ret;
5034}
5035
5036/*
5037 * Split part or all of the extent record at split_index in the leaf
5038 * pointed to by path. Merge with the contiguous extent record if needed.
5039 *
5040 * Care is taken to handle contiguousness so as to not grow the tree.
5041 *
5042 * meta_ac is not strictly necessary - we only truly need it if growth
5043 * of the tree is required. All other cases will degrade into a less
5044 * optimal tree layout.
5045 *
5046 * last_eb_bh should be the rightmost leaf block for any extent
5047 * btree. Since a split may grow the tree or a merge might shrink it,
5048 * the caller cannot trust the contents of that buffer after this call.
5049 *
5050 * This code is optimized for readability - several passes might be
5051 * made over certain portions of the tree. All of those blocks will
5052 * have been brought into cache (and pinned via the journal), so the
5053 * extra overhead is not expressed in terms of disk reads.
5054 */
5055int ocfs2_split_extent(handle_t *handle,
5056		       struct ocfs2_extent_tree *et,
5057		       struct ocfs2_path *path,
5058		       int split_index,
5059		       struct ocfs2_extent_rec *split_rec,
5060		       struct ocfs2_alloc_context *meta_ac,
5061		       struct ocfs2_cached_dealloc_ctxt *dealloc)
5062{
5063	int ret = 0;
5064	struct ocfs2_extent_list *el = path_leaf_el(path);
5065	struct buffer_head *last_eb_bh = NULL;
5066	struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
5067	struct ocfs2_merge_ctxt ctxt;
 
5068
5069	if (le32_to_cpu(rec->e_cpos) > le32_to_cpu(split_rec->e_cpos) ||
5070	    ((le32_to_cpu(rec->e_cpos) + le16_to_cpu(rec->e_leaf_clusters)) <
5071	     (le32_to_cpu(split_rec->e_cpos) + le16_to_cpu(split_rec->e_leaf_clusters)))) {
5072		ret = -EIO;
5073		mlog_errno(ret);
5074		goto out;
5075	}
5076
5077	ret = ocfs2_figure_merge_contig_type(et, path, el,
5078					     split_index,
5079					     split_rec,
5080					     &ctxt);
5081	if (ret) {
5082		mlog_errno(ret);
5083		goto out;
5084	}
5085
5086	/*
5087	 * The core merge / split code wants to know how much room is
5088	 * left in this allocation tree, so we pass the
5089	 * rightmost extent list.
5090	 */
5091	if (path->p_tree_depth) {
 
 
5092		ret = ocfs2_read_extent_block(et->et_ci,
5093					      ocfs2_et_get_last_eb_blk(et),
5094					      &last_eb_bh);
5095		if (ret) {
5096			mlog_errno(ret);
5097			goto out;
5098		}
5099	}
 
 
 
 
5100
5101	if (rec->e_cpos == split_rec->e_cpos &&
5102	    rec->e_leaf_clusters == split_rec->e_leaf_clusters)
5103		ctxt.c_split_covers_rec = 1;
5104	else
5105		ctxt.c_split_covers_rec = 0;
5106
5107	ctxt.c_has_empty_extent = ocfs2_is_empty_extent(&el->l_recs[0]);
5108
5109	trace_ocfs2_split_extent(split_index, ctxt.c_contig_type,
5110				 ctxt.c_has_empty_extent,
5111				 ctxt.c_split_covers_rec);
5112
5113	if (ctxt.c_contig_type == CONTIG_NONE) {
5114		if (ctxt.c_split_covers_rec)
5115			ret = ocfs2_replace_extent_rec(handle, et, path, el,
5116						       split_index, split_rec);
5117		else
5118			ret = ocfs2_split_and_insert(handle, et, path,
5119						     &last_eb_bh, split_index,
5120						     split_rec, meta_ac);
5121		if (ret)
5122			mlog_errno(ret);
5123	} else {
5124		ret = ocfs2_try_to_merge_extent(handle, et, path,
5125						split_index, split_rec,
5126						dealloc, &ctxt);
5127		if (ret)
5128			mlog_errno(ret);
5129	}
5130
5131out:
5132	brelse(last_eb_bh);
5133	return ret;
5134}
5135
5136/*
5137 * Change the flags of the already-existing extent at cpos for len clusters.
5138 *
5139 * new_flags: the flags we want to set.
5140 * clear_flags: the flags we want to clear.
5141 * phys: the new physical offset we want this new extent starts from.
5142 *
5143 * If the existing extent is larger than the request, initiate a
5144 * split. An attempt will be made at merging with adjacent extents.
5145 *
5146 * The caller is responsible for passing down meta_ac if we'll need it.
5147 */
5148int ocfs2_change_extent_flag(handle_t *handle,
5149			     struct ocfs2_extent_tree *et,
5150			     u32 cpos, u32 len, u32 phys,
5151			     struct ocfs2_alloc_context *meta_ac,
5152			     struct ocfs2_cached_dealloc_ctxt *dealloc,
5153			     int new_flags, int clear_flags)
5154{
5155	int ret, index;
5156	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
5157	u64 start_blkno = ocfs2_clusters_to_blocks(sb, phys);
5158	struct ocfs2_extent_rec split_rec;
5159	struct ocfs2_path *left_path = NULL;
5160	struct ocfs2_extent_list *el;
5161	struct ocfs2_extent_rec *rec;
5162
5163	left_path = ocfs2_new_path_from_et(et);
5164	if (!left_path) {
5165		ret = -ENOMEM;
5166		mlog_errno(ret);
5167		goto out;
5168	}
5169
5170	ret = ocfs2_find_path(et->et_ci, left_path, cpos);
5171	if (ret) {
5172		mlog_errno(ret);
5173		goto out;
5174	}
5175	el = path_leaf_el(left_path);
5176
5177	index = ocfs2_search_extent_list(el, cpos);
5178	if (index == -1) {
5179		ocfs2_error(sb,
5180			    "Owner %llu has an extent at cpos %u which can no longer be found\n",
5181			    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5182			    cpos);
 
5183		ret = -EROFS;
5184		goto out;
5185	}
5186
5187	ret = -EIO;
5188	rec = &el->l_recs[index];
5189	if (new_flags && (rec->e_flags & new_flags)) {
5190		mlog(ML_ERROR, "Owner %llu tried to set %d flags on an "
5191		     "extent that already had them\n",
5192		     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5193		     new_flags);
5194		goto out;
5195	}
5196
5197	if (clear_flags && !(rec->e_flags & clear_flags)) {
5198		mlog(ML_ERROR, "Owner %llu tried to clear %d flags on an "
5199		     "extent that didn't have them\n",
5200		     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5201		     clear_flags);
5202		goto out;
5203	}
5204
5205	memset(&split_rec, 0, sizeof(struct ocfs2_extent_rec));
5206	split_rec.e_cpos = cpu_to_le32(cpos);
5207	split_rec.e_leaf_clusters = cpu_to_le16(len);
5208	split_rec.e_blkno = cpu_to_le64(start_blkno);
5209	split_rec.e_flags = rec->e_flags;
5210	if (new_flags)
5211		split_rec.e_flags |= new_flags;
5212	if (clear_flags)
5213		split_rec.e_flags &= ~clear_flags;
5214
5215	ret = ocfs2_split_extent(handle, et, left_path,
5216				 index, &split_rec, meta_ac,
5217				 dealloc);
5218	if (ret)
5219		mlog_errno(ret);
5220
5221out:
5222	ocfs2_free_path(left_path);
5223	return ret;
5224
5225}
5226
5227/*
5228 * Mark the already-existing extent at cpos as written for len clusters.
5229 * This removes the unwritten extent flag.
5230 *
5231 * If the existing extent is larger than the request, initiate a
5232 * split. An attempt will be made at merging with adjacent extents.
5233 *
5234 * The caller is responsible for passing down meta_ac if we'll need it.
5235 */
5236int ocfs2_mark_extent_written(struct inode *inode,
5237			      struct ocfs2_extent_tree *et,
5238			      handle_t *handle, u32 cpos, u32 len, u32 phys,
5239			      struct ocfs2_alloc_context *meta_ac,
5240			      struct ocfs2_cached_dealloc_ctxt *dealloc)
5241{
5242	int ret;
5243
5244	trace_ocfs2_mark_extent_written(
5245		(unsigned long long)OCFS2_I(inode)->ip_blkno,
5246		cpos, len, phys);
5247
5248	if (!ocfs2_writes_unwritten_extents(OCFS2_SB(inode->i_sb))) {
5249		ocfs2_error(inode->i_sb, "Inode %llu has unwritten extents that are being written to, but the feature bit is not set in the super block\n",
 
 
5250			    (unsigned long long)OCFS2_I(inode)->ip_blkno);
5251		ret = -EROFS;
5252		goto out;
5253	}
5254
5255	/*
5256	 * XXX: This should be fixed up so that we just re-insert the
5257	 * next extent records.
5258	 */
5259	ocfs2_et_extent_map_truncate(et, 0);
5260
5261	ret = ocfs2_change_extent_flag(handle, et, cpos,
5262				       len, phys, meta_ac, dealloc,
5263				       0, OCFS2_EXT_UNWRITTEN);
5264	if (ret)
5265		mlog_errno(ret);
5266
5267out:
5268	return ret;
5269}
5270
5271static int ocfs2_split_tree(handle_t *handle, struct ocfs2_extent_tree *et,
5272			    struct ocfs2_path *path,
5273			    int index, u32 new_range,
5274			    struct ocfs2_alloc_context *meta_ac)
5275{
5276	int ret, depth, credits;
5277	struct buffer_head *last_eb_bh = NULL;
5278	struct ocfs2_extent_block *eb;
5279	struct ocfs2_extent_list *rightmost_el, *el;
5280	struct ocfs2_extent_rec split_rec;
5281	struct ocfs2_extent_rec *rec;
5282	struct ocfs2_insert_type insert;
5283
5284	/*
5285	 * Setup the record to split before we grow the tree.
5286	 */
5287	el = path_leaf_el(path);
5288	rec = &el->l_recs[index];
5289	ocfs2_make_right_split_rec(ocfs2_metadata_cache_get_super(et->et_ci),
5290				   &split_rec, new_range, rec);
5291
5292	depth = path->p_tree_depth;
5293	if (depth > 0) {
5294		ret = ocfs2_read_extent_block(et->et_ci,
5295					      ocfs2_et_get_last_eb_blk(et),
5296					      &last_eb_bh);
5297		if (ret < 0) {
5298			mlog_errno(ret);
5299			goto out;
5300		}
5301
5302		eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
5303		rightmost_el = &eb->h_list;
5304	} else
5305		rightmost_el = path_leaf_el(path);
5306
5307	credits = path->p_tree_depth +
5308		  ocfs2_extend_meta_needed(et->et_root_el);
5309	ret = ocfs2_extend_trans(handle, credits);
5310	if (ret) {
5311		mlog_errno(ret);
5312		goto out;
5313	}
5314
5315	if (le16_to_cpu(rightmost_el->l_next_free_rec) ==
5316	    le16_to_cpu(rightmost_el->l_count)) {
5317		ret = ocfs2_grow_tree(handle, et, &depth, &last_eb_bh,
5318				      meta_ac);
5319		if (ret) {
5320			mlog_errno(ret);
5321			goto out;
5322		}
5323	}
5324
5325	memset(&insert, 0, sizeof(struct ocfs2_insert_type));
5326	insert.ins_appending = APPEND_NONE;
5327	insert.ins_contig = CONTIG_NONE;
5328	insert.ins_split = SPLIT_RIGHT;
5329	insert.ins_tree_depth = depth;
5330
5331	ret = ocfs2_do_insert_extent(handle, et, &split_rec, &insert);
5332	if (ret)
5333		mlog_errno(ret);
5334
5335out:
5336	brelse(last_eb_bh);
5337	return ret;
5338}
5339
5340static int ocfs2_truncate_rec(handle_t *handle,
5341			      struct ocfs2_extent_tree *et,
5342			      struct ocfs2_path *path, int index,
5343			      struct ocfs2_cached_dealloc_ctxt *dealloc,
5344			      u32 cpos, u32 len)
5345{
5346	int ret;
5347	u32 left_cpos, rec_range, trunc_range;
5348	int is_rightmost_tree_rec = 0;
5349	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
5350	struct ocfs2_path *left_path = NULL;
5351	struct ocfs2_extent_list *el = path_leaf_el(path);
5352	struct ocfs2_extent_rec *rec;
5353	struct ocfs2_extent_block *eb;
5354
5355	if (ocfs2_is_empty_extent(&el->l_recs[0]) && index > 0) {
5356		/* extend credit for ocfs2_remove_rightmost_path */
5357		ret = ocfs2_extend_rotate_transaction(handle, 0,
5358				jbd2_handle_buffer_credits(handle),
5359				path);
5360		if (ret) {
5361			mlog_errno(ret);
5362			goto out;
5363		}
5364
5365		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
5366		if (ret) {
5367			mlog_errno(ret);
5368			goto out;
5369		}
5370
5371		index--;
5372	}
5373
5374	if (index == (le16_to_cpu(el->l_next_free_rec) - 1) &&
5375	    path->p_tree_depth) {
5376		/*
5377		 * Check whether this is the rightmost tree record. If
5378		 * we remove all of this record or part of its right
5379		 * edge then an update of the record lengths above it
5380		 * will be required.
5381		 */
5382		eb = (struct ocfs2_extent_block *)path_leaf_bh(path)->b_data;
5383		if (eb->h_next_leaf_blk == 0)
5384			is_rightmost_tree_rec = 1;
5385	}
5386
5387	rec = &el->l_recs[index];
5388	if (index == 0 && path->p_tree_depth &&
5389	    le32_to_cpu(rec->e_cpos) == cpos) {
5390		/*
5391		 * Changing the leftmost offset (via partial or whole
5392		 * record truncate) of an interior (or rightmost) path
5393		 * means we have to update the subtree that is formed
5394		 * by this leaf and the one to it's left.
5395		 *
5396		 * There are two cases we can skip:
5397		 *   1) Path is the leftmost one in our btree.
5398		 *   2) The leaf is rightmost and will be empty after
5399		 *      we remove the extent record - the rotate code
5400		 *      knows how to update the newly formed edge.
5401		 */
5402
5403		ret = ocfs2_find_cpos_for_left_leaf(sb, path, &left_cpos);
5404		if (ret) {
5405			mlog_errno(ret);
5406			goto out;
5407		}
5408
5409		if (left_cpos && le16_to_cpu(el->l_next_free_rec) > 1) {
5410			left_path = ocfs2_new_path_from_path(path);
5411			if (!left_path) {
5412				ret = -ENOMEM;
5413				mlog_errno(ret);
5414				goto out;
5415			}
5416
5417			ret = ocfs2_find_path(et->et_ci, left_path,
5418					      left_cpos);
5419			if (ret) {
5420				mlog_errno(ret);
5421				goto out;
5422			}
5423		}
5424	}
5425
5426	ret = ocfs2_extend_rotate_transaction(handle, 0,
5427					jbd2_handle_buffer_credits(handle),
5428					path);
5429	if (ret) {
5430		mlog_errno(ret);
5431		goto out;
5432	}
5433
5434	ret = ocfs2_journal_access_path(et->et_ci, handle, path);
5435	if (ret) {
5436		mlog_errno(ret);
5437		goto out;
5438	}
5439
5440	ret = ocfs2_journal_access_path(et->et_ci, handle, left_path);
5441	if (ret) {
5442		mlog_errno(ret);
5443		goto out;
5444	}
5445
5446	rec_range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
5447	trunc_range = cpos + len;
5448
5449	if (le32_to_cpu(rec->e_cpos) == cpos && rec_range == trunc_range) {
5450		int next_free;
5451
5452		memset(rec, 0, sizeof(*rec));
5453		ocfs2_cleanup_merge(el, index);
 
5454
5455		next_free = le16_to_cpu(el->l_next_free_rec);
5456		if (is_rightmost_tree_rec && next_free > 1) {
5457			/*
5458			 * We skip the edge update if this path will
5459			 * be deleted by the rotate code.
5460			 */
5461			rec = &el->l_recs[next_free - 1];
5462			ocfs2_adjust_rightmost_records(handle, et, path,
5463						       rec);
5464		}
5465	} else if (le32_to_cpu(rec->e_cpos) == cpos) {
5466		/* Remove leftmost portion of the record. */
5467		le32_add_cpu(&rec->e_cpos, len);
5468		le64_add_cpu(&rec->e_blkno, ocfs2_clusters_to_blocks(sb, len));
5469		le16_add_cpu(&rec->e_leaf_clusters, -len);
5470	} else if (rec_range == trunc_range) {
5471		/* Remove rightmost portion of the record */
5472		le16_add_cpu(&rec->e_leaf_clusters, -len);
5473		if (is_rightmost_tree_rec)
5474			ocfs2_adjust_rightmost_records(handle, et, path, rec);
5475	} else {
5476		/* Caller should have trapped this. */
5477		mlog(ML_ERROR, "Owner %llu: Invalid record truncate: (%u, %u) "
5478		     "(%u, %u)\n",
5479		     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5480		     le32_to_cpu(rec->e_cpos),
5481		     le16_to_cpu(rec->e_leaf_clusters), cpos, len);
5482		BUG();
5483	}
5484
5485	if (left_path) {
5486		int subtree_index;
5487
5488		subtree_index = ocfs2_find_subtree_root(et, left_path, path);
5489		ocfs2_complete_edge_insert(handle, left_path, path,
5490					   subtree_index);
5491	}
5492
5493	ocfs2_journal_dirty(handle, path_leaf_bh(path));
5494
5495	ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
5496	if (ret)
5497		mlog_errno(ret);
 
 
5498
5499out:
5500	ocfs2_free_path(left_path);
5501	return ret;
5502}
5503
5504int ocfs2_remove_extent(handle_t *handle,
5505			struct ocfs2_extent_tree *et,
5506			u32 cpos, u32 len,
5507			struct ocfs2_alloc_context *meta_ac,
5508			struct ocfs2_cached_dealloc_ctxt *dealloc)
5509{
5510	int ret, index;
5511	u32 rec_range, trunc_range;
5512	struct ocfs2_extent_rec *rec;
5513	struct ocfs2_extent_list *el;
5514	struct ocfs2_path *path = NULL;
5515
5516	/*
5517	 * XXX: Why are we truncating to 0 instead of wherever this
5518	 * affects us?
5519	 */
5520	ocfs2_et_extent_map_truncate(et, 0);
5521
5522	path = ocfs2_new_path_from_et(et);
5523	if (!path) {
5524		ret = -ENOMEM;
5525		mlog_errno(ret);
5526		goto out;
5527	}
5528
5529	ret = ocfs2_find_path(et->et_ci, path, cpos);
5530	if (ret) {
5531		mlog_errno(ret);
5532		goto out;
5533	}
5534
5535	el = path_leaf_el(path);
5536	index = ocfs2_search_extent_list(el, cpos);
5537	if (index == -1) {
5538		ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5539			    "Owner %llu has an extent at cpos %u which can no longer be found\n",
 
5540			    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5541			    cpos);
5542		ret = -EROFS;
5543		goto out;
5544	}
5545
5546	/*
5547	 * We have 3 cases of extent removal:
5548	 *   1) Range covers the entire extent rec
5549	 *   2) Range begins or ends on one edge of the extent rec
5550	 *   3) Range is in the middle of the extent rec (no shared edges)
5551	 *
5552	 * For case 1 we remove the extent rec and left rotate to
5553	 * fill the hole.
5554	 *
5555	 * For case 2 we just shrink the existing extent rec, with a
5556	 * tree update if the shrinking edge is also the edge of an
5557	 * extent block.
5558	 *
5559	 * For case 3 we do a right split to turn the extent rec into
5560	 * something case 2 can handle.
5561	 */
5562	rec = &el->l_recs[index];
5563	rec_range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
5564	trunc_range = cpos + len;
5565
5566	BUG_ON(cpos < le32_to_cpu(rec->e_cpos) || trunc_range > rec_range);
5567
5568	trace_ocfs2_remove_extent(
5569		(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5570		cpos, len, index, le32_to_cpu(rec->e_cpos),
5571		ocfs2_rec_clusters(el, rec));
5572
5573	if (le32_to_cpu(rec->e_cpos) == cpos || rec_range == trunc_range) {
5574		ret = ocfs2_truncate_rec(handle, et, path, index, dealloc,
5575					 cpos, len);
5576		if (ret) {
5577			mlog_errno(ret);
5578			goto out;
5579		}
5580	} else {
5581		ret = ocfs2_split_tree(handle, et, path, index,
5582				       trunc_range, meta_ac);
5583		if (ret) {
5584			mlog_errno(ret);
5585			goto out;
5586		}
5587
5588		/*
5589		 * The split could have manipulated the tree enough to
5590		 * move the record location, so we have to look for it again.
5591		 */
5592		ocfs2_reinit_path(path, 1);
5593
5594		ret = ocfs2_find_path(et->et_ci, path, cpos);
5595		if (ret) {
5596			mlog_errno(ret);
5597			goto out;
5598		}
5599
5600		el = path_leaf_el(path);
5601		index = ocfs2_search_extent_list(el, cpos);
5602		if (index == -1) {
5603			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5604				    "Owner %llu: split at cpos %u lost record\n",
5605				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5606				    cpos);
5607			ret = -EROFS;
5608			goto out;
5609		}
5610
5611		/*
5612		 * Double check our values here. If anything is fishy,
5613		 * it's easier to catch it at the top level.
5614		 */
5615		rec = &el->l_recs[index];
5616		rec_range = le32_to_cpu(rec->e_cpos) +
5617			ocfs2_rec_clusters(el, rec);
5618		if (rec_range != trunc_range) {
5619			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5620				    "Owner %llu: error after split at cpos %u trunc len %u, existing record is (%u,%u)\n",
 
5621				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5622				    cpos, len, le32_to_cpu(rec->e_cpos),
5623				    ocfs2_rec_clusters(el, rec));
5624			ret = -EROFS;
5625			goto out;
5626		}
5627
5628		ret = ocfs2_truncate_rec(handle, et, path, index, dealloc,
5629					 cpos, len);
5630		if (ret)
5631			mlog_errno(ret);
 
 
5632	}
5633
5634out:
5635	ocfs2_free_path(path);
5636	return ret;
5637}
5638
5639/*
5640 * ocfs2_reserve_blocks_for_rec_trunc() would look basically the
5641 * same as ocfs2_lock_alloctors(), except for it accepts a blocks
5642 * number to reserve some extra blocks, and it only handles meta
5643 * data allocations.
5644 *
5645 * Currently, only ocfs2_remove_btree_range() uses it for truncating
5646 * and punching holes.
5647 */
5648static int ocfs2_reserve_blocks_for_rec_trunc(struct inode *inode,
5649					      struct ocfs2_extent_tree *et,
5650					      u32 extents_to_split,
5651					      struct ocfs2_alloc_context **ac,
5652					      int extra_blocks)
5653{
5654	int ret = 0, num_free_extents;
5655	unsigned int max_recs_needed = 2 * extents_to_split;
5656	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
5657
5658	*ac = NULL;
5659
5660	num_free_extents = ocfs2_num_free_extents(et);
5661	if (num_free_extents < 0) {
5662		ret = num_free_extents;
5663		mlog_errno(ret);
5664		goto out;
5665	}
5666
5667	if (!num_free_extents ||
5668	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
5669		extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
5670
5671	if (extra_blocks) {
5672		ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, ac);
5673		if (ret < 0) {
5674			if (ret != -ENOSPC)
5675				mlog_errno(ret);
 
5676		}
5677	}
5678
5679out:
5680	if (ret) {
5681		if (*ac) {
5682			ocfs2_free_alloc_context(*ac);
5683			*ac = NULL;
5684		}
5685	}
5686
5687	return ret;
5688}
5689
5690int ocfs2_remove_btree_range(struct inode *inode,
5691			     struct ocfs2_extent_tree *et,
5692			     u32 cpos, u32 phys_cpos, u32 len, int flags,
5693			     struct ocfs2_cached_dealloc_ctxt *dealloc,
5694			     u64 refcount_loc, bool refcount_tree_locked)
5695{
5696	int ret, credits = 0, extra_blocks = 0;
5697	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
5698	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
5699	struct inode *tl_inode = osb->osb_tl_inode;
5700	handle_t *handle;
5701	struct ocfs2_alloc_context *meta_ac = NULL;
5702	struct ocfs2_refcount_tree *ref_tree = NULL;
5703
5704	if ((flags & OCFS2_EXT_REFCOUNTED) && len) {
5705		BUG_ON(!ocfs2_is_refcount_inode(inode));
 
5706
5707		if (!refcount_tree_locked) {
5708			ret = ocfs2_lock_refcount_tree(osb, refcount_loc, 1,
5709						       &ref_tree, NULL);
5710			if (ret) {
5711				mlog_errno(ret);
5712				goto bail;
5713			}
5714		}
5715
5716		ret = ocfs2_prepare_refcount_change_for_del(inode,
5717							    refcount_loc,
5718							    phys_blkno,
5719							    len,
5720							    &credits,
5721							    &extra_blocks);
5722		if (ret < 0) {
5723			mlog_errno(ret);
5724			goto bail;
5725		}
5726	}
5727
5728	ret = ocfs2_reserve_blocks_for_rec_trunc(inode, et, 1, &meta_ac,
5729						 extra_blocks);
5730	if (ret) {
5731		mlog_errno(ret);
5732		goto bail;
5733	}
5734
5735	inode_lock(tl_inode);
5736
5737	if (ocfs2_truncate_log_needs_flush(osb)) {
5738		ret = __ocfs2_flush_truncate_log(osb);
5739		if (ret < 0) {
5740			mlog_errno(ret);
5741			goto out;
5742		}
5743	}
5744
5745	handle = ocfs2_start_trans(osb,
5746			ocfs2_remove_extent_credits(osb->sb) + credits);
5747	if (IS_ERR(handle)) {
5748		ret = PTR_ERR(handle);
5749		mlog_errno(ret);
5750		goto out;
5751	}
5752
5753	ret = ocfs2_et_root_journal_access(handle, et,
5754					   OCFS2_JOURNAL_ACCESS_WRITE);
5755	if (ret) {
5756		mlog_errno(ret);
5757		goto out_commit;
5758	}
5759
5760	dquot_free_space_nodirty(inode,
5761				  ocfs2_clusters_to_bytes(inode->i_sb, len));
5762
5763	ret = ocfs2_remove_extent(handle, et, cpos, len, meta_ac, dealloc);
5764	if (ret) {
5765		mlog_errno(ret);
5766		goto out_commit;
5767	}
5768
5769	ocfs2_et_update_clusters(et, -len);
5770	ocfs2_update_inode_fsync_trans(handle, inode, 1);
5771
5772	ocfs2_journal_dirty(handle, et->et_root_bh);
5773
5774	if (phys_blkno) {
5775		if (flags & OCFS2_EXT_REFCOUNTED)
5776			ret = ocfs2_decrease_refcount(inode, handle,
5777					ocfs2_blocks_to_clusters(osb->sb,
5778								 phys_blkno),
5779					len, meta_ac,
5780					dealloc, 1);
5781		else
5782			ret = ocfs2_truncate_log_append(osb, handle,
5783							phys_blkno, len);
5784		if (ret)
5785			mlog_errno(ret);
5786
5787	}
5788
5789out_commit:
5790	ocfs2_commit_trans(osb, handle);
5791out:
5792	inode_unlock(tl_inode);
5793bail:
5794	if (meta_ac)
5795		ocfs2_free_alloc_context(meta_ac);
5796
5797	if (ref_tree)
5798		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
5799
5800	return ret;
5801}
5802
5803int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb)
5804{
5805	struct buffer_head *tl_bh = osb->osb_tl_bh;
5806	struct ocfs2_dinode *di;
5807	struct ocfs2_truncate_log *tl;
5808
5809	di = (struct ocfs2_dinode *) tl_bh->b_data;
5810	tl = &di->id2.i_dealloc;
5811
5812	mlog_bug_on_msg(le16_to_cpu(tl->tl_used) > le16_to_cpu(tl->tl_count),
5813			"slot %d, invalid truncate log parameters: used = "
5814			"%u, count = %u\n", osb->slot_num,
5815			le16_to_cpu(tl->tl_used), le16_to_cpu(tl->tl_count));
5816	return le16_to_cpu(tl->tl_used) == le16_to_cpu(tl->tl_count);
5817}
5818
5819static int ocfs2_truncate_log_can_coalesce(struct ocfs2_truncate_log *tl,
5820					   unsigned int new_start)
5821{
5822	unsigned int tail_index;
5823	unsigned int current_tail;
5824
5825	/* No records, nothing to coalesce */
5826	if (!le16_to_cpu(tl->tl_used))
5827		return 0;
5828
5829	tail_index = le16_to_cpu(tl->tl_used) - 1;
5830	current_tail = le32_to_cpu(tl->tl_recs[tail_index].t_start);
5831	current_tail += le32_to_cpu(tl->tl_recs[tail_index].t_clusters);
5832
5833	return current_tail == new_start;
5834}
5835
5836int ocfs2_truncate_log_append(struct ocfs2_super *osb,
5837			      handle_t *handle,
5838			      u64 start_blk,
5839			      unsigned int num_clusters)
5840{
5841	int status, index;
5842	unsigned int start_cluster, tl_count;
5843	struct inode *tl_inode = osb->osb_tl_inode;
5844	struct buffer_head *tl_bh = osb->osb_tl_bh;
5845	struct ocfs2_dinode *di;
5846	struct ocfs2_truncate_log *tl;
5847
5848	BUG_ON(inode_trylock(tl_inode));
5849
5850	start_cluster = ocfs2_blocks_to_clusters(osb->sb, start_blk);
5851
5852	di = (struct ocfs2_dinode *) tl_bh->b_data;
5853
5854	/* tl_bh is loaded from ocfs2_truncate_log_init().  It's validated
5855	 * by the underlying call to ocfs2_read_inode_block(), so any
5856	 * corruption is a code bug */
5857	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
5858
5859	tl = &di->id2.i_dealloc;
5860	tl_count = le16_to_cpu(tl->tl_count);
5861	mlog_bug_on_msg(tl_count > ocfs2_truncate_recs_per_inode(osb->sb) ||
5862			tl_count == 0,
5863			"Truncate record count on #%llu invalid "
5864			"wanted %u, actual %u\n",
5865			(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
5866			ocfs2_truncate_recs_per_inode(osb->sb),
5867			le16_to_cpu(tl->tl_count));
5868
5869	/* Caller should have known to flush before calling us. */
5870	index = le16_to_cpu(tl->tl_used);
5871	if (index >= tl_count) {
5872		status = -ENOSPC;
5873		mlog_errno(status);
5874		goto bail;
5875	}
5876
5877	status = ocfs2_journal_access_di(handle, INODE_CACHE(tl_inode), tl_bh,
5878					 OCFS2_JOURNAL_ACCESS_WRITE);
5879	if (status < 0) {
5880		mlog_errno(status);
5881		goto bail;
5882	}
5883
5884	trace_ocfs2_truncate_log_append(
5885		(unsigned long long)OCFS2_I(tl_inode)->ip_blkno, index,
5886		start_cluster, num_clusters);
5887	if (ocfs2_truncate_log_can_coalesce(tl, start_cluster)) {
5888		/*
5889		 * Move index back to the record we are coalescing with.
5890		 * ocfs2_truncate_log_can_coalesce() guarantees nonzero
5891		 */
5892		index--;
5893
5894		num_clusters += le32_to_cpu(tl->tl_recs[index].t_clusters);
5895		trace_ocfs2_truncate_log_append(
5896			(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
5897			index, le32_to_cpu(tl->tl_recs[index].t_start),
5898			num_clusters);
5899	} else {
5900		tl->tl_recs[index].t_start = cpu_to_le32(start_cluster);
5901		tl->tl_used = cpu_to_le16(index + 1);
5902	}
5903	tl->tl_recs[index].t_clusters = cpu_to_le32(num_clusters);
5904
5905	ocfs2_journal_dirty(handle, tl_bh);
5906
5907	osb->truncated_clusters += num_clusters;
5908bail:
5909	return status;
5910}
5911
5912static int ocfs2_replay_truncate_records(struct ocfs2_super *osb,
 
5913					 struct inode *data_alloc_inode,
5914					 struct buffer_head *data_alloc_bh)
5915{
5916	int status = 0;
5917	int i;
5918	unsigned int num_clusters;
5919	u64 start_blk;
5920	struct ocfs2_truncate_rec rec;
5921	struct ocfs2_dinode *di;
5922	struct ocfs2_truncate_log *tl;
5923	struct inode *tl_inode = osb->osb_tl_inode;
5924	struct buffer_head *tl_bh = osb->osb_tl_bh;
5925	handle_t *handle;
5926
5927	di = (struct ocfs2_dinode *) tl_bh->b_data;
5928	tl = &di->id2.i_dealloc;
5929	i = le16_to_cpu(tl->tl_used) - 1;
5930	while (i >= 0) {
5931		handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC);
5932		if (IS_ERR(handle)) {
5933			status = PTR_ERR(handle);
5934			mlog_errno(status);
5935			goto bail;
5936		}
5937
5938		/* Caller has given us at least enough credits to
5939		 * update the truncate log dinode */
5940		status = ocfs2_journal_access_di(handle, INODE_CACHE(tl_inode), tl_bh,
5941						 OCFS2_JOURNAL_ACCESS_WRITE);
5942		if (status < 0) {
5943			ocfs2_commit_trans(osb, handle);
5944			mlog_errno(status);
5945			goto bail;
5946		}
5947
5948		tl->tl_used = cpu_to_le16(i);
5949
5950		ocfs2_journal_dirty(handle, tl_bh);
5951
 
 
 
 
 
 
 
 
 
 
5952		rec = tl->tl_recs[i];
5953		start_blk = ocfs2_clusters_to_blocks(data_alloc_inode->i_sb,
5954						    le32_to_cpu(rec.t_start));
5955		num_clusters = le32_to_cpu(rec.t_clusters);
5956
5957		/* if start_blk is not set, we ignore the record as
5958		 * invalid. */
5959		if (start_blk) {
5960			trace_ocfs2_replay_truncate_records(
5961				(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
5962				i, le32_to_cpu(rec.t_start), num_clusters);
5963
5964			status = ocfs2_free_clusters(handle, data_alloc_inode,
5965						     data_alloc_bh, start_blk,
5966						     num_clusters);
5967			if (status < 0) {
5968				ocfs2_commit_trans(osb, handle);
5969				mlog_errno(status);
5970				goto bail;
5971			}
5972		}
5973
5974		ocfs2_commit_trans(osb, handle);
5975		i--;
5976	}
5977
5978	osb->truncated_clusters = 0;
5979
5980bail:
5981	return status;
5982}
5983
5984/* Expects you to already be holding tl_inode->i_rwsem */
5985int __ocfs2_flush_truncate_log(struct ocfs2_super *osb)
5986{
5987	int status;
5988	unsigned int num_to_flush;
 
5989	struct inode *tl_inode = osb->osb_tl_inode;
5990	struct inode *data_alloc_inode = NULL;
5991	struct buffer_head *tl_bh = osb->osb_tl_bh;
5992	struct buffer_head *data_alloc_bh = NULL;
5993	struct ocfs2_dinode *di;
5994	struct ocfs2_truncate_log *tl;
5995	struct ocfs2_journal *journal = osb->journal;
5996
5997	BUG_ON(inode_trylock(tl_inode));
5998
5999	di = (struct ocfs2_dinode *) tl_bh->b_data;
6000
6001	/* tl_bh is loaded from ocfs2_truncate_log_init().  It's validated
6002	 * by the underlying call to ocfs2_read_inode_block(), so any
6003	 * corruption is a code bug */
6004	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
6005
6006	tl = &di->id2.i_dealloc;
6007	num_to_flush = le16_to_cpu(tl->tl_used);
6008	trace_ocfs2_flush_truncate_log(
6009		(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
6010		num_to_flush);
6011	if (!num_to_flush) {
6012		status = 0;
6013		goto out;
6014	}
6015
6016	/* Appending truncate log(TA) and flushing truncate log(TF) are
6017	 * two separated transactions. They can be both committed but not
6018	 * checkpointed. If crash occurs then, both two transaction will be
6019	 * replayed with several already released to global bitmap clusters.
6020	 * Then truncate log will be replayed resulting in cluster double free.
6021	 */
6022	jbd2_journal_lock_updates(journal->j_journal);
6023	status = jbd2_journal_flush(journal->j_journal, 0);
6024	jbd2_journal_unlock_updates(journal->j_journal);
6025	if (status < 0) {
6026		mlog_errno(status);
6027		goto out;
6028	}
6029
6030	data_alloc_inode = ocfs2_get_system_file_inode(osb,
6031						       GLOBAL_BITMAP_SYSTEM_INODE,
6032						       OCFS2_INVALID_SLOT);
6033	if (!data_alloc_inode) {
6034		status = -EINVAL;
6035		mlog(ML_ERROR, "Could not get bitmap inode!\n");
6036		goto out;
6037	}
6038
6039	inode_lock(data_alloc_inode);
6040
6041	status = ocfs2_inode_lock(data_alloc_inode, &data_alloc_bh, 1);
6042	if (status < 0) {
6043		mlog_errno(status);
6044		goto out_mutex;
6045	}
6046
6047	status = ocfs2_replay_truncate_records(osb, data_alloc_inode,
 
 
 
 
 
 
 
6048					       data_alloc_bh);
6049	if (status < 0)
6050		mlog_errno(status);
6051
 
 
 
6052	brelse(data_alloc_bh);
6053	ocfs2_inode_unlock(data_alloc_inode, 1);
6054
6055out_mutex:
6056	inode_unlock(data_alloc_inode);
6057	iput(data_alloc_inode);
6058
6059out:
6060	return status;
6061}
6062
6063int ocfs2_flush_truncate_log(struct ocfs2_super *osb)
6064{
6065	int status;
6066	struct inode *tl_inode = osb->osb_tl_inode;
6067
6068	inode_lock(tl_inode);
6069	status = __ocfs2_flush_truncate_log(osb);
6070	inode_unlock(tl_inode);
6071
6072	return status;
6073}
6074
6075static void ocfs2_truncate_log_worker(struct work_struct *work)
6076{
6077	int status;
6078	struct ocfs2_super *osb =
6079		container_of(work, struct ocfs2_super,
6080			     osb_truncate_log_wq.work);
6081
6082	status = ocfs2_flush_truncate_log(osb);
6083	if (status < 0)
6084		mlog_errno(status);
6085	else
6086		ocfs2_init_steal_slots(osb);
6087}
6088
6089#define OCFS2_TRUNCATE_LOG_FLUSH_INTERVAL (2 * HZ)
6090void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb,
6091				       int cancel)
6092{
6093	if (osb->osb_tl_inode &&
6094			atomic_read(&osb->osb_tl_disable) == 0) {
6095		/* We want to push off log flushes while truncates are
6096		 * still running. */
6097		if (cancel)
6098			cancel_delayed_work(&osb->osb_truncate_log_wq);
6099
6100		queue_delayed_work(osb->ocfs2_wq, &osb->osb_truncate_log_wq,
6101				   OCFS2_TRUNCATE_LOG_FLUSH_INTERVAL);
6102	}
6103}
6104
6105/*
6106 * Try to flush truncate logs if we can free enough clusters from it.
6107 * As for return value, "< 0" means error, "0" no space and "1" means
6108 * we have freed enough spaces and let the caller try to allocate again.
6109 */
6110int ocfs2_try_to_free_truncate_log(struct ocfs2_super *osb,
6111					unsigned int needed)
6112{
6113	tid_t target;
6114	int ret = 0;
6115	unsigned int truncated_clusters;
6116
6117	inode_lock(osb->osb_tl_inode);
6118	truncated_clusters = osb->truncated_clusters;
6119	inode_unlock(osb->osb_tl_inode);
6120
6121	/*
6122	 * Check whether we can succeed in allocating if we free
6123	 * the truncate log.
6124	 */
6125	if (truncated_clusters < needed)
6126		goto out;
6127
6128	ret = ocfs2_flush_truncate_log(osb);
6129	if (ret) {
6130		mlog_errno(ret);
6131		goto out;
6132	}
6133
6134	if (jbd2_journal_start_commit(osb->journal->j_journal, &target)) {
6135		jbd2_log_wait_commit(osb->journal->j_journal, target);
6136		ret = 1;
6137	}
6138out:
6139	return ret;
6140}
6141
6142static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb,
6143				       int slot_num,
6144				       struct inode **tl_inode,
6145				       struct buffer_head **tl_bh)
6146{
6147	int status;
6148	struct inode *inode = NULL;
6149	struct buffer_head *bh = NULL;
6150
6151	inode = ocfs2_get_system_file_inode(osb,
6152					   TRUNCATE_LOG_SYSTEM_INODE,
6153					   slot_num);
6154	if (!inode) {
6155		status = -EINVAL;
6156		mlog(ML_ERROR, "Could not get load truncate log inode!\n");
6157		goto bail;
6158	}
6159
6160	status = ocfs2_read_inode_block(inode, &bh);
6161	if (status < 0) {
6162		iput(inode);
6163		mlog_errno(status);
6164		goto bail;
6165	}
6166
6167	*tl_inode = inode;
6168	*tl_bh    = bh;
6169bail:
6170	return status;
6171}
6172
6173/* called during the 1st stage of node recovery. we stamp a clean
6174 * truncate log and pass back a copy for processing later. if the
6175 * truncate log does not require processing, a *tl_copy is set to
6176 * NULL. */
6177int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb,
6178				      int slot_num,
6179				      struct ocfs2_dinode **tl_copy)
6180{
6181	int status;
6182	struct inode *tl_inode = NULL;
6183	struct buffer_head *tl_bh = NULL;
6184	struct ocfs2_dinode *di;
6185	struct ocfs2_truncate_log *tl;
6186
6187	*tl_copy = NULL;
6188
6189	trace_ocfs2_begin_truncate_log_recovery(slot_num);
6190
6191	status = ocfs2_get_truncate_log_info(osb, slot_num, &tl_inode, &tl_bh);
6192	if (status < 0) {
6193		mlog_errno(status);
6194		goto bail;
6195	}
6196
6197	di = (struct ocfs2_dinode *) tl_bh->b_data;
6198
6199	/* tl_bh is loaded from ocfs2_get_truncate_log_info().  It's
6200	 * validated by the underlying call to ocfs2_read_inode_block(),
6201	 * so any corruption is a code bug */
6202	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
6203
6204	tl = &di->id2.i_dealloc;
6205	if (le16_to_cpu(tl->tl_used)) {
6206		trace_ocfs2_truncate_log_recovery_num(le16_to_cpu(tl->tl_used));
6207
6208		/*
6209		 * Assuming the write-out below goes well, this copy will be
6210		 * passed back to recovery for processing.
6211		 */
6212		*tl_copy = kmemdup(tl_bh->b_data, tl_bh->b_size, GFP_KERNEL);
6213		if (!(*tl_copy)) {
6214			status = -ENOMEM;
6215			mlog_errno(status);
6216			goto bail;
6217		}
6218
 
 
 
 
6219		/* All we need to do to clear the truncate log is set
6220		 * tl_used. */
6221		tl->tl_used = 0;
6222
6223		ocfs2_compute_meta_ecc(osb->sb, tl_bh->b_data, &di->i_check);
6224		status = ocfs2_write_block(osb, tl_bh, INODE_CACHE(tl_inode));
6225		if (status < 0) {
6226			mlog_errno(status);
6227			goto bail;
6228		}
6229	}
6230
6231bail:
6232	iput(tl_inode);
 
6233	brelse(tl_bh);
6234
6235	if (status < 0) {
6236		kfree(*tl_copy);
6237		*tl_copy = NULL;
6238		mlog_errno(status);
6239	}
6240
6241	return status;
6242}
6243
6244int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb,
6245					 struct ocfs2_dinode *tl_copy)
6246{
6247	int status = 0;
6248	int i;
6249	unsigned int clusters, num_recs, start_cluster;
6250	u64 start_blk;
6251	handle_t *handle;
6252	struct inode *tl_inode = osb->osb_tl_inode;
6253	struct ocfs2_truncate_log *tl;
6254
6255	if (OCFS2_I(tl_inode)->ip_blkno == le64_to_cpu(tl_copy->i_blkno)) {
6256		mlog(ML_ERROR, "Asked to recover my own truncate log!\n");
6257		return -EINVAL;
6258	}
6259
6260	tl = &tl_copy->id2.i_dealloc;
6261	num_recs = le16_to_cpu(tl->tl_used);
6262	trace_ocfs2_complete_truncate_log_recovery(
6263		(unsigned long long)le64_to_cpu(tl_copy->i_blkno),
6264		num_recs);
6265
6266	inode_lock(tl_inode);
6267	for(i = 0; i < num_recs; i++) {
6268		if (ocfs2_truncate_log_needs_flush(osb)) {
6269			status = __ocfs2_flush_truncate_log(osb);
6270			if (status < 0) {
6271				mlog_errno(status);
6272				goto bail_up;
6273			}
6274		}
6275
6276		handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_UPDATE);
6277		if (IS_ERR(handle)) {
6278			status = PTR_ERR(handle);
6279			mlog_errno(status);
6280			goto bail_up;
6281		}
6282
6283		clusters = le32_to_cpu(tl->tl_recs[i].t_clusters);
6284		start_cluster = le32_to_cpu(tl->tl_recs[i].t_start);
6285		start_blk = ocfs2_clusters_to_blocks(osb->sb, start_cluster);
6286
6287		status = ocfs2_truncate_log_append(osb, handle,
6288						   start_blk, clusters);
6289		ocfs2_commit_trans(osb, handle);
6290		if (status < 0) {
6291			mlog_errno(status);
6292			goto bail_up;
6293		}
6294	}
6295
6296bail_up:
6297	inode_unlock(tl_inode);
6298
6299	return status;
6300}
6301
6302void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb)
6303{
6304	int status;
6305	struct inode *tl_inode = osb->osb_tl_inode;
6306
6307	atomic_set(&osb->osb_tl_disable, 1);
6308
6309	if (tl_inode) {
6310		cancel_delayed_work(&osb->osb_truncate_log_wq);
6311		flush_workqueue(osb->ocfs2_wq);
6312
6313		status = ocfs2_flush_truncate_log(osb);
6314		if (status < 0)
6315			mlog_errno(status);
6316
6317		brelse(osb->osb_tl_bh);
6318		iput(osb->osb_tl_inode);
6319	}
6320}
6321
6322int ocfs2_truncate_log_init(struct ocfs2_super *osb)
6323{
6324	int status;
6325	struct inode *tl_inode = NULL;
6326	struct buffer_head *tl_bh = NULL;
6327
6328	status = ocfs2_get_truncate_log_info(osb,
6329					     osb->slot_num,
6330					     &tl_inode,
6331					     &tl_bh);
6332	if (status < 0)
6333		mlog_errno(status);
6334
6335	/* ocfs2_truncate_log_shutdown keys on the existence of
6336	 * osb->osb_tl_inode so we don't set any of the osb variables
6337	 * until we're sure all is well. */
6338	INIT_DELAYED_WORK(&osb->osb_truncate_log_wq,
6339			  ocfs2_truncate_log_worker);
6340	atomic_set(&osb->osb_tl_disable, 0);
6341	osb->osb_tl_bh    = tl_bh;
6342	osb->osb_tl_inode = tl_inode;
6343
6344	return status;
6345}
6346
6347/*
6348 * Delayed de-allocation of suballocator blocks.
6349 *
6350 * Some sets of block de-allocations might involve multiple suballocator inodes.
6351 *
6352 * The locking for this can get extremely complicated, especially when
6353 * the suballocator inodes to delete from aren't known until deep
6354 * within an unrelated codepath.
6355 *
6356 * ocfs2_extent_block structures are a good example of this - an inode
6357 * btree could have been grown by any number of nodes each allocating
6358 * out of their own suballoc inode.
6359 *
6360 * These structures allow the delay of block de-allocation until a
6361 * later time, when locking of multiple cluster inodes won't cause
6362 * deadlock.
6363 */
6364
6365/*
6366 * Describe a single bit freed from a suballocator.  For the block
6367 * suballocators, it represents one block.  For the global cluster
6368 * allocator, it represents some clusters and free_bit indicates
6369 * clusters number.
6370 */
6371struct ocfs2_cached_block_free {
6372	struct ocfs2_cached_block_free		*free_next;
6373	u64					free_bg;
6374	u64					free_blk;
6375	unsigned int				free_bit;
6376};
6377
6378struct ocfs2_per_slot_free_list {
6379	struct ocfs2_per_slot_free_list		*f_next_suballocator;
6380	int					f_inode_type;
6381	int					f_slot;
6382	struct ocfs2_cached_block_free		*f_first;
6383};
6384
6385static int ocfs2_free_cached_blocks(struct ocfs2_super *osb,
6386				    int sysfile_type,
6387				    int slot,
6388				    struct ocfs2_cached_block_free *head)
6389{
6390	int ret;
6391	u64 bg_blkno;
6392	handle_t *handle;
6393	struct inode *inode;
6394	struct buffer_head *di_bh = NULL;
6395	struct ocfs2_cached_block_free *tmp;
6396
6397	inode = ocfs2_get_system_file_inode(osb, sysfile_type, slot);
6398	if (!inode) {
6399		ret = -EINVAL;
6400		mlog_errno(ret);
6401		goto out;
6402	}
6403
6404	inode_lock(inode);
6405
6406	ret = ocfs2_inode_lock(inode, &di_bh, 1);
6407	if (ret) {
6408		mlog_errno(ret);
6409		goto out_mutex;
6410	}
6411
 
 
 
 
 
 
 
6412	while (head) {
6413		if (head->free_bg)
6414			bg_blkno = head->free_bg;
6415		else
6416			bg_blkno = ocfs2_which_suballoc_group(head->free_blk,
6417							      head->free_bit);
6418		handle = ocfs2_start_trans(osb, OCFS2_SUBALLOC_FREE);
6419		if (IS_ERR(handle)) {
6420			ret = PTR_ERR(handle);
6421			mlog_errno(ret);
6422			goto out_unlock;
6423		}
6424
6425		trace_ocfs2_free_cached_blocks(
6426		     (unsigned long long)head->free_blk, head->free_bit);
6427
6428		ret = ocfs2_free_suballoc_bits(handle, inode, di_bh,
6429					       head->free_bit, bg_blkno, 1);
6430		if (ret)
6431			mlog_errno(ret);
 
 
6432
6433		ocfs2_commit_trans(osb, handle);
 
 
 
 
6434
6435		tmp = head;
6436		head = head->free_next;
6437		kfree(tmp);
6438	}
6439
 
 
 
6440out_unlock:
6441	ocfs2_inode_unlock(inode, 1);
6442	brelse(di_bh);
6443out_mutex:
6444	inode_unlock(inode);
6445	iput(inode);
6446out:
6447	while(head) {
6448		/* Premature exit may have left some dangling items. */
6449		tmp = head;
6450		head = head->free_next;
6451		kfree(tmp);
6452	}
6453
6454	return ret;
6455}
6456
6457int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
6458				u64 blkno, unsigned int bit)
6459{
6460	int ret = 0;
6461	struct ocfs2_cached_block_free *item;
6462
6463	item = kzalloc(sizeof(*item), GFP_NOFS);
6464	if (item == NULL) {
6465		ret = -ENOMEM;
6466		mlog_errno(ret);
6467		return ret;
6468	}
6469
6470	trace_ocfs2_cache_cluster_dealloc((unsigned long long)blkno, bit);
6471
6472	item->free_blk = blkno;
6473	item->free_bit = bit;
6474	item->free_next = ctxt->c_global_allocator;
6475
6476	ctxt->c_global_allocator = item;
6477	return ret;
6478}
6479
6480static int ocfs2_free_cached_clusters(struct ocfs2_super *osb,
6481				      struct ocfs2_cached_block_free *head)
6482{
6483	struct ocfs2_cached_block_free *tmp;
6484	struct inode *tl_inode = osb->osb_tl_inode;
6485	handle_t *handle;
6486	int ret = 0;
6487
6488	inode_lock(tl_inode);
6489
6490	while (head) {
6491		if (ocfs2_truncate_log_needs_flush(osb)) {
6492			ret = __ocfs2_flush_truncate_log(osb);
6493			if (ret < 0) {
6494				mlog_errno(ret);
6495				break;
6496			}
6497		}
6498
6499		handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_UPDATE);
6500		if (IS_ERR(handle)) {
6501			ret = PTR_ERR(handle);
6502			mlog_errno(ret);
6503			break;
6504		}
6505
6506		ret = ocfs2_truncate_log_append(osb, handle, head->free_blk,
6507						head->free_bit);
6508
6509		ocfs2_commit_trans(osb, handle);
6510		tmp = head;
6511		head = head->free_next;
6512		kfree(tmp);
6513
6514		if (ret < 0) {
6515			mlog_errno(ret);
6516			break;
6517		}
6518	}
6519
6520	inode_unlock(tl_inode);
6521
6522	while (head) {
6523		/* Premature exit may have left some dangling items. */
6524		tmp = head;
6525		head = head->free_next;
6526		kfree(tmp);
6527	}
6528
6529	return ret;
6530}
6531
6532int ocfs2_run_deallocs(struct ocfs2_super *osb,
6533		       struct ocfs2_cached_dealloc_ctxt *ctxt)
6534{
6535	int ret = 0, ret2;
6536	struct ocfs2_per_slot_free_list *fl;
6537
6538	if (!ctxt)
6539		return 0;
6540
6541	while (ctxt->c_first_suballocator) {
6542		fl = ctxt->c_first_suballocator;
6543
6544		if (fl->f_first) {
6545			trace_ocfs2_run_deallocs(fl->f_inode_type,
6546						 fl->f_slot);
6547			ret2 = ocfs2_free_cached_blocks(osb,
6548							fl->f_inode_type,
6549							fl->f_slot,
6550							fl->f_first);
6551			if (ret2)
6552				mlog_errno(ret2);
6553			if (!ret)
6554				ret = ret2;
6555		}
6556
6557		ctxt->c_first_suballocator = fl->f_next_suballocator;
6558		kfree(fl);
6559	}
6560
6561	if (ctxt->c_global_allocator) {
6562		ret2 = ocfs2_free_cached_clusters(osb,
6563						  ctxt->c_global_allocator);
6564		if (ret2)
6565			mlog_errno(ret2);
6566		if (!ret)
6567			ret = ret2;
6568
6569		ctxt->c_global_allocator = NULL;
6570	}
6571
6572	return ret;
6573}
6574
6575static struct ocfs2_per_slot_free_list *
6576ocfs2_find_per_slot_free_list(int type,
6577			      int slot,
6578			      struct ocfs2_cached_dealloc_ctxt *ctxt)
6579{
6580	struct ocfs2_per_slot_free_list *fl = ctxt->c_first_suballocator;
6581
6582	while (fl) {
6583		if (fl->f_inode_type == type && fl->f_slot == slot)
6584			return fl;
6585
6586		fl = fl->f_next_suballocator;
6587	}
6588
6589	fl = kmalloc(sizeof(*fl), GFP_NOFS);
6590	if (fl) {
6591		fl->f_inode_type = type;
6592		fl->f_slot = slot;
6593		fl->f_first = NULL;
6594		fl->f_next_suballocator = ctxt->c_first_suballocator;
6595
6596		ctxt->c_first_suballocator = fl;
6597	}
6598	return fl;
6599}
6600
6601static struct ocfs2_per_slot_free_list *
6602ocfs2_find_preferred_free_list(int type,
6603			       int preferred_slot,
6604			       int *real_slot,
6605			       struct ocfs2_cached_dealloc_ctxt *ctxt)
6606{
6607	struct ocfs2_per_slot_free_list *fl = ctxt->c_first_suballocator;
6608
6609	while (fl) {
6610		if (fl->f_inode_type == type && fl->f_slot == preferred_slot) {
6611			*real_slot = fl->f_slot;
6612			return fl;
6613		}
6614
6615		fl = fl->f_next_suballocator;
6616	}
6617
6618	/* If we can't find any free list matching preferred slot, just use
6619	 * the first one.
6620	 */
6621	fl = ctxt->c_first_suballocator;
6622	*real_slot = fl->f_slot;
6623
6624	return fl;
6625}
6626
6627/* Return Value 1 indicates empty */
6628static int ocfs2_is_dealloc_empty(struct ocfs2_extent_tree *et)
6629{
6630	struct ocfs2_per_slot_free_list *fl = NULL;
6631
6632	if (!et->et_dealloc)
6633		return 1;
6634
6635	fl = et->et_dealloc->c_first_suballocator;
6636	if (!fl)
6637		return 1;
6638
6639	if (!fl->f_first)
6640		return 1;
6641
6642	return 0;
6643}
6644
6645/* If extent was deleted from tree due to extent rotation and merging, and
6646 * no metadata is reserved ahead of time. Try to reuse some extents
6647 * just deleted. This is only used to reuse extent blocks.
6648 * It is supposed to find enough extent blocks in dealloc if our estimation
6649 * on metadata is accurate.
6650 */
6651static int ocfs2_reuse_blk_from_dealloc(handle_t *handle,
6652					struct ocfs2_extent_tree *et,
6653					struct buffer_head **new_eb_bh,
6654					int blk_wanted, int *blk_given)
6655{
6656	int i, status = 0, real_slot;
6657	struct ocfs2_cached_dealloc_ctxt *dealloc;
6658	struct ocfs2_per_slot_free_list *fl;
6659	struct ocfs2_cached_block_free *bf;
6660	struct ocfs2_extent_block *eb;
6661	struct ocfs2_super *osb =
6662		OCFS2_SB(ocfs2_metadata_cache_get_super(et->et_ci));
6663
6664	*blk_given = 0;
6665
6666	/* If extent tree doesn't have a dealloc, this is not faulty. Just
6667	 * tell upper caller dealloc can't provide any block and it should
6668	 * ask for alloc to claim more space.
6669	 */
6670	dealloc = et->et_dealloc;
6671	if (!dealloc)
6672		goto bail;
6673
6674	for (i = 0; i < blk_wanted; i++) {
6675		/* Prefer to use local slot */
6676		fl = ocfs2_find_preferred_free_list(EXTENT_ALLOC_SYSTEM_INODE,
6677						    osb->slot_num, &real_slot,
6678						    dealloc);
6679		/* If no more block can be reused, we should claim more
6680		 * from alloc. Just return here normally.
6681		 */
6682		if (!fl) {
6683			status = 0;
6684			break;
6685		}
6686
6687		bf = fl->f_first;
6688		fl->f_first = bf->free_next;
6689
6690		new_eb_bh[i] = sb_getblk(osb->sb, bf->free_blk);
6691		if (new_eb_bh[i] == NULL) {
6692			status = -ENOMEM;
6693			mlog_errno(status);
6694			goto bail;
6695		}
6696
6697		mlog(0, "Reusing block(%llu) from "
6698		     "dealloc(local slot:%d, real slot:%d)\n",
6699		     bf->free_blk, osb->slot_num, real_slot);
6700
6701		ocfs2_set_new_buffer_uptodate(et->et_ci, new_eb_bh[i]);
6702
6703		status = ocfs2_journal_access_eb(handle, et->et_ci,
6704						 new_eb_bh[i],
6705						 OCFS2_JOURNAL_ACCESS_CREATE);
6706		if (status < 0) {
6707			mlog_errno(status);
6708			goto bail;
6709		}
6710
6711		memset(new_eb_bh[i]->b_data, 0, osb->sb->s_blocksize);
6712		eb = (struct ocfs2_extent_block *) new_eb_bh[i]->b_data;
6713
6714		/* We can't guarantee that buffer head is still cached, so
6715		 * polutlate the extent block again.
6716		 */
6717		strcpy(eb->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE);
6718		eb->h_blkno = cpu_to_le64(bf->free_blk);
6719		eb->h_fs_generation = cpu_to_le32(osb->fs_generation);
6720		eb->h_suballoc_slot = cpu_to_le16(real_slot);
6721		eb->h_suballoc_loc = cpu_to_le64(bf->free_bg);
6722		eb->h_suballoc_bit = cpu_to_le16(bf->free_bit);
6723		eb->h_list.l_count =
6724			cpu_to_le16(ocfs2_extent_recs_per_eb(osb->sb));
6725
6726		/* We'll also be dirtied by the caller, so
6727		 * this isn't absolutely necessary.
6728		 */
6729		ocfs2_journal_dirty(handle, new_eb_bh[i]);
6730
6731		if (!fl->f_first) {
6732			dealloc->c_first_suballocator = fl->f_next_suballocator;
6733			kfree(fl);
6734		}
6735		kfree(bf);
6736	}
6737
6738	*blk_given = i;
6739
6740bail:
6741	if (unlikely(status < 0)) {
6742		for (i = 0; i < blk_wanted; i++)
6743			brelse(new_eb_bh[i]);
6744	}
6745
6746	return status;
6747}
6748
6749int ocfs2_cache_block_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
6750			      int type, int slot, u64 suballoc,
6751			      u64 blkno, unsigned int bit)
6752{
6753	int ret;
6754	struct ocfs2_per_slot_free_list *fl;
6755	struct ocfs2_cached_block_free *item;
6756
6757	fl = ocfs2_find_per_slot_free_list(type, slot, ctxt);
6758	if (fl == NULL) {
6759		ret = -ENOMEM;
6760		mlog_errno(ret);
6761		goto out;
6762	}
6763
6764	item = kzalloc(sizeof(*item), GFP_NOFS);
6765	if (item == NULL) {
6766		ret = -ENOMEM;
6767		mlog_errno(ret);
6768		goto out;
6769	}
6770
6771	trace_ocfs2_cache_block_dealloc(type, slot,
6772					(unsigned long long)suballoc,
6773					(unsigned long long)blkno, bit);
6774
6775	item->free_bg = suballoc;
6776	item->free_blk = blkno;
6777	item->free_bit = bit;
6778	item->free_next = fl->f_first;
6779
6780	fl->f_first = item;
6781
6782	ret = 0;
6783out:
6784	return ret;
6785}
6786
6787static int ocfs2_cache_extent_block_free(struct ocfs2_cached_dealloc_ctxt *ctxt,
6788					 struct ocfs2_extent_block *eb)
6789{
6790	return ocfs2_cache_block_dealloc(ctxt, EXTENT_ALLOC_SYSTEM_INODE,
6791					 le16_to_cpu(eb->h_suballoc_slot),
6792					 le64_to_cpu(eb->h_suballoc_loc),
6793					 le64_to_cpu(eb->h_blkno),
6794					 le16_to_cpu(eb->h_suballoc_bit));
6795}
6796
6797static int ocfs2_zero_func(handle_t *handle, struct buffer_head *bh)
6798{
6799	set_buffer_uptodate(bh);
6800	mark_buffer_dirty(bh);
6801	return 0;
6802}
6803
6804void ocfs2_map_and_dirty_page(struct inode *inode, handle_t *handle,
6805			      unsigned int from, unsigned int to,
6806			      struct page *page, int zero, u64 *phys)
6807{
6808	int ret, partial = 0;
6809	loff_t start_byte = ((loff_t)page->index << PAGE_SHIFT) + from;
6810	loff_t length = to - from;
6811
6812	ret = ocfs2_map_page_blocks(page, phys, inode, from, to, 0);
6813	if (ret)
6814		mlog_errno(ret);
6815
6816	if (zero)
6817		zero_user_segment(page, from, to);
6818
6819	/*
6820	 * Need to set the buffers we zero'd into uptodate
6821	 * here if they aren't - ocfs2_map_page_blocks()
6822	 * might've skipped some
6823	 */
6824	ret = walk_page_buffers(handle, page_buffers(page),
6825				from, to, &partial,
6826				ocfs2_zero_func);
6827	if (ret < 0)
6828		mlog_errno(ret);
6829	else if (ocfs2_should_order_data(inode)) {
6830		ret = ocfs2_jbd2_inode_add_write(handle, inode,
6831						 start_byte, length);
6832		if (ret < 0)
6833			mlog_errno(ret);
6834	}
6835
6836	if (!partial)
6837		SetPageUptodate(page);
6838
6839	flush_dcache_page(page);
6840}
6841
6842static void ocfs2_zero_cluster_pages(struct inode *inode, loff_t start,
6843				     loff_t end, struct page **pages,
6844				     int numpages, u64 phys, handle_t *handle)
6845{
6846	int i;
6847	struct page *page;
6848	unsigned int from, to = PAGE_SIZE;
6849	struct super_block *sb = inode->i_sb;
6850
6851	BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(sb)));
6852
6853	if (numpages == 0)
6854		goto out;
6855
6856	to = PAGE_SIZE;
6857	for(i = 0; i < numpages; i++) {
6858		page = pages[i];
6859
6860		from = start & (PAGE_SIZE - 1);
6861		if ((end >> PAGE_SHIFT) == page->index)
6862			to = end & (PAGE_SIZE - 1);
6863
6864		BUG_ON(from > PAGE_SIZE);
6865		BUG_ON(to > PAGE_SIZE);
6866
6867		ocfs2_map_and_dirty_page(inode, handle, from, to, page, 1,
6868					 &phys);
6869
6870		start = (page->index + 1) << PAGE_SHIFT;
6871	}
6872out:
6873	if (pages)
6874		ocfs2_unlock_and_free_pages(pages, numpages);
6875}
6876
6877int ocfs2_grab_pages(struct inode *inode, loff_t start, loff_t end,
6878		     struct page **pages, int *num)
6879{
6880	int numpages, ret = 0;
6881	struct address_space *mapping = inode->i_mapping;
6882	unsigned long index;
6883	loff_t last_page_bytes;
6884
6885	BUG_ON(start > end);
6886
6887	numpages = 0;
6888	last_page_bytes = PAGE_ALIGN(end);
6889	index = start >> PAGE_SHIFT;
6890	do {
6891		pages[numpages] = find_or_create_page(mapping, index, GFP_NOFS);
6892		if (!pages[numpages]) {
6893			ret = -ENOMEM;
6894			mlog_errno(ret);
6895			goto out;
6896		}
6897
6898		numpages++;
6899		index++;
6900	} while (index < (last_page_bytes >> PAGE_SHIFT));
6901
6902out:
6903	if (ret != 0) {
6904		if (pages)
6905			ocfs2_unlock_and_free_pages(pages, numpages);
6906		numpages = 0;
6907	}
6908
6909	*num = numpages;
6910
6911	return ret;
6912}
6913
6914static int ocfs2_grab_eof_pages(struct inode *inode, loff_t start, loff_t end,
6915				struct page **pages, int *num)
6916{
6917	struct super_block *sb = inode->i_sb;
6918
6919	BUG_ON(start >> OCFS2_SB(sb)->s_clustersize_bits !=
6920	       (end - 1) >> OCFS2_SB(sb)->s_clustersize_bits);
6921
6922	return ocfs2_grab_pages(inode, start, end, pages, num);
6923}
6924
6925/*
6926 * Zero partial cluster for a hole punch or truncate. This avoids exposing
6927 * nonzero data on subsequent file extends.
 
6928 *
6929 * We need to call this before i_size is updated on the inode because
6930 * otherwise block_write_full_page() will skip writeout of pages past
6931 * i_size.
6932 */
6933int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle,
6934				  u64 range_start, u64 range_end)
6935{
6936	int ret = 0, numpages;
6937	struct page **pages = NULL;
6938	u64 phys;
6939	unsigned int ext_flags;
6940	struct super_block *sb = inode->i_sb;
6941
6942	/*
6943	 * File systems which don't support sparse files zero on every
6944	 * extend.
6945	 */
6946	if (!ocfs2_sparse_alloc(OCFS2_SB(sb)))
6947		return 0;
6948
6949	/*
6950	 * Avoid zeroing pages fully beyond current i_size. It is pointless as
6951	 * underlying blocks of those pages should be already zeroed out and
6952	 * page writeback will skip them anyway.
6953	 */
6954	range_end = min_t(u64, range_end, i_size_read(inode));
6955	if (range_start >= range_end)
6956		return 0;
6957
6958	pages = kcalloc(ocfs2_pages_per_cluster(sb),
6959			sizeof(struct page *), GFP_NOFS);
6960	if (pages == NULL) {
6961		ret = -ENOMEM;
6962		mlog_errno(ret);
6963		goto out;
6964	}
6965
 
 
 
6966	ret = ocfs2_extent_map_get_blocks(inode,
6967					  range_start >> sb->s_blocksize_bits,
6968					  &phys, NULL, &ext_flags);
6969	if (ret) {
6970		mlog_errno(ret);
6971		goto out;
6972	}
6973
6974	/*
6975	 * Tail is a hole, or is marked unwritten. In either case, we
6976	 * can count on read and write to return/push zero's.
6977	 */
6978	if (phys == 0 || ext_flags & OCFS2_EXT_UNWRITTEN)
6979		goto out;
6980
6981	ret = ocfs2_grab_eof_pages(inode, range_start, range_end, pages,
6982				   &numpages);
6983	if (ret) {
6984		mlog_errno(ret);
6985		goto out;
6986	}
6987
6988	ocfs2_zero_cluster_pages(inode, range_start, range_end, pages,
6989				 numpages, phys, handle);
6990
6991	/*
6992	 * Initiate writeout of the pages we zero'd here. We don't
6993	 * wait on them - the truncate_inode_pages() call later will
6994	 * do that for us.
6995	 */
6996	ret = filemap_fdatawrite_range(inode->i_mapping, range_start,
6997				       range_end - 1);
6998	if (ret)
6999		mlog_errno(ret);
7000
7001out:
7002	kfree(pages);
 
7003
7004	return ret;
7005}
7006
7007static void ocfs2_zero_dinode_id2_with_xattr(struct inode *inode,
7008					     struct ocfs2_dinode *di)
7009{
7010	unsigned int blocksize = 1 << inode->i_sb->s_blocksize_bits;
7011	unsigned int xattrsize = le16_to_cpu(di->i_xattr_inline_size);
7012
7013	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_XATTR_FL)
7014		memset(&di->id2, 0, blocksize -
7015				    offsetof(struct ocfs2_dinode, id2) -
7016				    xattrsize);
7017	else
7018		memset(&di->id2, 0, blocksize -
7019				    offsetof(struct ocfs2_dinode, id2));
7020}
7021
7022void ocfs2_dinode_new_extent_list(struct inode *inode,
7023				  struct ocfs2_dinode *di)
7024{
7025	ocfs2_zero_dinode_id2_with_xattr(inode, di);
7026	di->id2.i_list.l_tree_depth = 0;
7027	di->id2.i_list.l_next_free_rec = 0;
7028	di->id2.i_list.l_count = cpu_to_le16(
7029		ocfs2_extent_recs_per_inode_with_xattr(inode->i_sb, di));
7030}
7031
7032void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di)
7033{
7034	struct ocfs2_inode_info *oi = OCFS2_I(inode);
7035	struct ocfs2_inline_data *idata = &di->id2.i_data;
7036
7037	spin_lock(&oi->ip_lock);
7038	oi->ip_dyn_features |= OCFS2_INLINE_DATA_FL;
7039	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
7040	spin_unlock(&oi->ip_lock);
7041
7042	/*
7043	 * We clear the entire i_data structure here so that all
7044	 * fields can be properly initialized.
7045	 */
7046	ocfs2_zero_dinode_id2_with_xattr(inode, di);
7047
7048	idata->id_count = cpu_to_le16(
7049			ocfs2_max_inline_data_with_xattr(inode->i_sb, di));
7050}
7051
7052int ocfs2_convert_inline_data_to_extents(struct inode *inode,
7053					 struct buffer_head *di_bh)
7054{
7055	int ret, has_data, num_pages = 0;
7056	int need_free = 0;
7057	u32 bit_off, num;
7058	handle_t *handle;
7059	u64 block;
7060	struct ocfs2_inode_info *oi = OCFS2_I(inode);
7061	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
7062	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
7063	struct ocfs2_alloc_context *data_ac = NULL;
7064	struct page *page = NULL;
 
7065	struct ocfs2_extent_tree et;
7066	int did_quota = 0;
7067
7068	has_data = i_size_read(inode) ? 1 : 0;
7069
7070	if (has_data) {
 
 
 
 
 
 
 
 
7071		ret = ocfs2_reserve_clusters(osb, 1, &data_ac);
7072		if (ret) {
7073			mlog_errno(ret);
7074			goto out;
7075		}
7076	}
7077
7078	handle = ocfs2_start_trans(osb,
7079				   ocfs2_inline_to_extents_credits(osb->sb));
7080	if (IS_ERR(handle)) {
7081		ret = PTR_ERR(handle);
7082		mlog_errno(ret);
7083		goto out;
7084	}
7085
7086	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
7087				      OCFS2_JOURNAL_ACCESS_WRITE);
7088	if (ret) {
7089		mlog_errno(ret);
7090		goto out_commit;
7091	}
7092
7093	if (has_data) {
7094		unsigned int page_end = min_t(unsigned, PAGE_SIZE,
7095							osb->s_clustersize);
7096		u64 phys;
7097
7098		ret = dquot_alloc_space_nodirty(inode,
7099				       ocfs2_clusters_to_bytes(osb->sb, 1));
7100		if (ret)
7101			goto out_commit;
7102		did_quota = 1;
7103
7104		data_ac->ac_resv = &oi->ip_la_data_resv;
7105
7106		ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off,
7107					   &num);
7108		if (ret) {
7109			mlog_errno(ret);
7110			goto out_commit;
7111		}
7112
7113		/*
7114		 * Save two copies, one for insert, and one that can
7115		 * be changed by ocfs2_map_and_dirty_page() below.
7116		 */
7117		block = phys = ocfs2_clusters_to_blocks(inode->i_sb, bit_off);
7118
7119		ret = ocfs2_grab_eof_pages(inode, 0, page_end, &page,
7120					   &num_pages);
 
 
 
 
 
 
 
7121		if (ret) {
7122			mlog_errno(ret);
7123			need_free = 1;
7124			goto out_commit;
7125		}
7126
7127		/*
7128		 * This should populate the 1st page for us and mark
7129		 * it up to date.
7130		 */
7131		ret = ocfs2_read_inline_data(inode, page, di_bh);
7132		if (ret) {
7133			mlog_errno(ret);
7134			need_free = 1;
7135			goto out_unlock;
7136		}
7137
7138		ocfs2_map_and_dirty_page(inode, handle, 0, page_end, page, 0,
7139					 &phys);
 
 
 
 
 
7140	}
7141
7142	spin_lock(&oi->ip_lock);
7143	oi->ip_dyn_features &= ~OCFS2_INLINE_DATA_FL;
7144	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
7145	spin_unlock(&oi->ip_lock);
7146
7147	ocfs2_update_inode_fsync_trans(handle, inode, 1);
7148	ocfs2_dinode_new_extent_list(inode, di);
7149
7150	ocfs2_journal_dirty(handle, di_bh);
7151
7152	if (has_data) {
7153		/*
7154		 * An error at this point should be extremely rare. If
7155		 * this proves to be false, we could always re-build
7156		 * the in-inode data from our pages.
7157		 */
7158		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
7159		ret = ocfs2_insert_extent(handle, &et, 0, block, 1, 0, NULL);
7160		if (ret) {
7161			mlog_errno(ret);
7162			need_free = 1;
7163			goto out_unlock;
7164		}
7165
7166		inode->i_blocks = ocfs2_inode_sector_count(inode);
7167	}
7168
7169out_unlock:
7170	if (page)
7171		ocfs2_unlock_and_free_pages(&page, num_pages);
7172
7173out_commit:
7174	if (ret < 0 && did_quota)
7175		dquot_free_space_nodirty(inode,
7176					  ocfs2_clusters_to_bytes(osb->sb, 1));
7177
7178	if (need_free) {
7179		if (data_ac->ac_which == OCFS2_AC_USE_LOCAL)
7180			ocfs2_free_local_alloc_bits(osb, handle, data_ac,
7181					bit_off, num);
7182		else
7183			ocfs2_free_clusters(handle,
7184					data_ac->ac_inode,
7185					data_ac->ac_bh,
7186					ocfs2_clusters_to_blocks(osb->sb, bit_off),
7187					num);
7188	}
7189
7190	ocfs2_commit_trans(osb, handle);
7191
7192out:
7193	if (data_ac)
7194		ocfs2_free_alloc_context(data_ac);
 
 
 
 
 
 
 
7195	return ret;
7196}
7197
7198/*
7199 * It is expected, that by the time you call this function,
7200 * inode->i_size and fe->i_size have been adjusted.
7201 *
7202 * WARNING: This will kfree the truncate context
7203 */
7204int ocfs2_commit_truncate(struct ocfs2_super *osb,
7205			  struct inode *inode,
7206			  struct buffer_head *di_bh)
7207{
7208	int status = 0, i, flags = 0;
7209	u32 new_highest_cpos, range, trunc_cpos, trunc_len, phys_cpos, coff;
7210	u64 blkno = 0;
7211	struct ocfs2_extent_list *el;
7212	struct ocfs2_extent_rec *rec;
7213	struct ocfs2_path *path = NULL;
7214	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
7215	struct ocfs2_extent_list *root_el = &(di->id2.i_list);
7216	u64 refcount_loc = le64_to_cpu(di->i_refcount_loc);
7217	struct ocfs2_extent_tree et;
7218	struct ocfs2_cached_dealloc_ctxt dealloc;
7219	struct ocfs2_refcount_tree *ref_tree = NULL;
7220
7221	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
7222	ocfs2_init_dealloc_ctxt(&dealloc);
7223
7224	new_highest_cpos = ocfs2_clusters_for_bytes(osb->sb,
7225						     i_size_read(inode));
7226
7227	path = ocfs2_new_path(di_bh, &di->id2.i_list,
7228			      ocfs2_journal_access_di);
7229	if (!path) {
7230		status = -ENOMEM;
7231		mlog_errno(status);
7232		goto bail;
7233	}
7234
7235	ocfs2_extent_map_trunc(inode, new_highest_cpos);
7236
7237start:
7238	/*
7239	 * Check that we still have allocation to delete.
7240	 */
7241	if (OCFS2_I(inode)->ip_clusters == 0) {
7242		status = 0;
7243		goto bail;
7244	}
7245
7246	/*
7247	 * Truncate always works against the rightmost tree branch.
7248	 */
7249	status = ocfs2_find_path(INODE_CACHE(inode), path, UINT_MAX);
7250	if (status) {
7251		mlog_errno(status);
7252		goto bail;
7253	}
7254
7255	trace_ocfs2_commit_truncate(
7256		(unsigned long long)OCFS2_I(inode)->ip_blkno,
7257		new_highest_cpos,
7258		OCFS2_I(inode)->ip_clusters,
7259		path->p_tree_depth);
7260
7261	/*
7262	 * By now, el will point to the extent list on the bottom most
7263	 * portion of this tree. Only the tail record is considered in
7264	 * each pass.
7265	 *
7266	 * We handle the following cases, in order:
7267	 * - empty extent: delete the remaining branch
7268	 * - remove the entire record
7269	 * - remove a partial record
7270	 * - no record needs to be removed (truncate has completed)
7271	 */
7272	el = path_leaf_el(path);
7273	if (le16_to_cpu(el->l_next_free_rec) == 0) {
7274		ocfs2_error(inode->i_sb,
7275			    "Inode %llu has empty extent block at %llu\n",
7276			    (unsigned long long)OCFS2_I(inode)->ip_blkno,
7277			    (unsigned long long)path_leaf_bh(path)->b_blocknr);
7278		status = -EROFS;
7279		goto bail;
7280	}
7281
7282	i = le16_to_cpu(el->l_next_free_rec) - 1;
7283	rec = &el->l_recs[i];
7284	flags = rec->e_flags;
7285	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
7286
7287	if (i == 0 && ocfs2_is_empty_extent(rec)) {
7288		/*
7289		 * Lower levels depend on this never happening, but it's best
7290		 * to check it up here before changing the tree.
7291		*/
7292		if (root_el->l_tree_depth && rec->e_int_clusters == 0) {
7293			mlog(ML_ERROR, "Inode %lu has an empty "
7294				    "extent record, depth %u\n", inode->i_ino,
7295				    le16_to_cpu(root_el->l_tree_depth));
7296			status = ocfs2_remove_rightmost_empty_extent(osb,
7297					&et, path, &dealloc);
7298			if (status) {
7299				mlog_errno(status);
7300				goto bail;
7301			}
7302
7303			ocfs2_reinit_path(path, 1);
7304			goto start;
7305		} else {
7306			trunc_cpos = le32_to_cpu(rec->e_cpos);
7307			trunc_len = 0;
7308			blkno = 0;
7309		}
 
 
 
7310	} else if (le32_to_cpu(rec->e_cpos) >= new_highest_cpos) {
7311		/*
7312		 * Truncate entire record.
7313		 */
7314		trunc_cpos = le32_to_cpu(rec->e_cpos);
7315		trunc_len = ocfs2_rec_clusters(el, rec);
7316		blkno = le64_to_cpu(rec->e_blkno);
7317	} else if (range > new_highest_cpos) {
7318		/*
7319		 * Partial truncate. it also should be
7320		 * the last truncate we're doing.
7321		 */
7322		trunc_cpos = new_highest_cpos;
7323		trunc_len = range - new_highest_cpos;
7324		coff = new_highest_cpos - le32_to_cpu(rec->e_cpos);
7325		blkno = le64_to_cpu(rec->e_blkno) +
7326				ocfs2_clusters_to_blocks(inode->i_sb, coff);
7327	} else {
7328		/*
7329		 * Truncate completed, leave happily.
7330		 */
7331		status = 0;
7332		goto bail;
7333	}
7334
7335	phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
7336
7337	if ((flags & OCFS2_EXT_REFCOUNTED) && trunc_len && !ref_tree) {
7338		status = ocfs2_lock_refcount_tree(osb, refcount_loc, 1,
7339				&ref_tree, NULL);
7340		if (status) {
7341			mlog_errno(status);
7342			goto bail;
7343		}
7344	}
7345
7346	status = ocfs2_remove_btree_range(inode, &et, trunc_cpos,
7347					  phys_cpos, trunc_len, flags, &dealloc,
7348					  refcount_loc, true);
7349	if (status < 0) {
7350		mlog_errno(status);
7351		goto bail;
7352	}
7353
7354	ocfs2_reinit_path(path, 1);
7355
7356	/*
7357	 * The check above will catch the case where we've truncated
7358	 * away all allocation.
7359	 */
7360	goto start;
7361
7362bail:
7363	if (ref_tree)
7364		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
7365
7366	ocfs2_schedule_truncate_log_flush(osb, 1);
7367
7368	ocfs2_run_deallocs(osb, &dealloc);
7369
7370	ocfs2_free_path(path);
7371
7372	return status;
7373}
7374
7375/*
7376 * 'start' is inclusive, 'end' is not.
7377 */
7378int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh,
7379			  unsigned int start, unsigned int end, int trunc)
7380{
7381	int ret;
7382	unsigned int numbytes;
7383	handle_t *handle;
7384	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
7385	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
7386	struct ocfs2_inline_data *idata = &di->id2.i_data;
7387
7388	/* No need to punch hole beyond i_size. */
7389	if (start >= i_size_read(inode))
7390		return 0;
7391
7392	if (end > i_size_read(inode))
7393		end = i_size_read(inode);
7394
7395	BUG_ON(start > end);
7396
7397	if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) ||
7398	    !(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL) ||
7399	    !ocfs2_supports_inline_data(osb)) {
7400		ocfs2_error(inode->i_sb,
7401			    "Inline data flags for inode %llu don't agree! Disk: 0x%x, Memory: 0x%x, Superblock: 0x%x\n",
 
7402			    (unsigned long long)OCFS2_I(inode)->ip_blkno,
7403			    le16_to_cpu(di->i_dyn_features),
7404			    OCFS2_I(inode)->ip_dyn_features,
7405			    osb->s_feature_incompat);
7406		ret = -EROFS;
7407		goto out;
7408	}
7409
7410	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
7411	if (IS_ERR(handle)) {
7412		ret = PTR_ERR(handle);
7413		mlog_errno(ret);
7414		goto out;
7415	}
7416
7417	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
7418				      OCFS2_JOURNAL_ACCESS_WRITE);
7419	if (ret) {
7420		mlog_errno(ret);
7421		goto out_commit;
7422	}
7423
7424	numbytes = end - start;
7425	memset(idata->id_data + start, 0, numbytes);
7426
7427	/*
7428	 * No need to worry about the data page here - it's been
7429	 * truncated already and inline data doesn't need it for
7430	 * pushing zero's to disk, so we'll let read_folio pick it up
7431	 * later.
7432	 */
7433	if (trunc) {
7434		i_size_write(inode, start);
7435		di->i_size = cpu_to_le64(start);
7436	}
7437
7438	inode->i_blocks = ocfs2_inode_sector_count(inode);
7439	inode->i_ctime = inode->i_mtime = current_time(inode);
7440
7441	di->i_ctime = di->i_mtime = cpu_to_le64(inode->i_ctime.tv_sec);
7442	di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
7443
7444	ocfs2_update_inode_fsync_trans(handle, inode, 1);
7445	ocfs2_journal_dirty(handle, di_bh);
7446
7447out_commit:
7448	ocfs2_commit_trans(osb, handle);
7449
7450out:
7451	return ret;
7452}
7453
7454static int ocfs2_trim_extent(struct super_block *sb,
7455			     struct ocfs2_group_desc *gd,
7456			     u64 group, u32 start, u32 count)
7457{
7458	u64 discard, bcount;
7459	struct ocfs2_super *osb = OCFS2_SB(sb);
7460
7461	bcount = ocfs2_clusters_to_blocks(sb, count);
7462	discard = ocfs2_clusters_to_blocks(sb, start);
7463
7464	/*
7465	 * For the first cluster group, the gd->bg_blkno is not at the start
7466	 * of the group, but at an offset from the start. If we add it while
7467	 * calculating discard for first group, we will wrongly start fstrim a
7468	 * few blocks after the desried start block and the range can cross
7469	 * over into the next cluster group. So, add it only if this is not
7470	 * the first cluster group.
7471	 */
7472	if (group != osb->first_cluster_group_blkno)
7473		discard += le64_to_cpu(gd->bg_blkno);
7474
7475	trace_ocfs2_trim_extent(sb, (unsigned long long)discard, bcount);
7476
7477	return sb_issue_discard(sb, discard, bcount, GFP_NOFS, 0);
7478}
7479
7480static int ocfs2_trim_group(struct super_block *sb,
7481			    struct ocfs2_group_desc *gd, u64 group,
7482			    u32 start, u32 max, u32 minbits)
7483{
7484	int ret = 0, count = 0, next;
7485	void *bitmap = gd->bg_bitmap;
7486
7487	if (le16_to_cpu(gd->bg_free_bits_count) < minbits)
7488		return 0;
7489
7490	trace_ocfs2_trim_group((unsigned long long)le64_to_cpu(gd->bg_blkno),
7491			       start, max, minbits);
7492
7493	while (start < max) {
7494		start = ocfs2_find_next_zero_bit(bitmap, max, start);
7495		if (start >= max)
7496			break;
7497		next = ocfs2_find_next_bit(bitmap, max, start);
7498
7499		if ((next - start) >= minbits) {
7500			ret = ocfs2_trim_extent(sb, gd, group,
7501						start, next - start);
7502			if (ret < 0) {
7503				mlog_errno(ret);
7504				break;
7505			}
7506			count += next - start;
7507		}
7508		start = next + 1;
7509
7510		if (fatal_signal_pending(current)) {
7511			count = -ERESTARTSYS;
7512			break;
7513		}
7514
7515		if ((le16_to_cpu(gd->bg_free_bits_count) - count) < minbits)
7516			break;
7517	}
7518
7519	if (ret < 0)
7520		count = ret;
7521
7522	return count;
7523}
7524
7525static
7526int ocfs2_trim_mainbm(struct super_block *sb, struct fstrim_range *range)
7527{
7528	struct ocfs2_super *osb = OCFS2_SB(sb);
7529	u64 start, len, trimmed = 0, first_group, last_group = 0, group = 0;
7530	int ret, cnt;
7531	u32 first_bit, last_bit, minlen;
7532	struct buffer_head *main_bm_bh = NULL;
7533	struct inode *main_bm_inode = NULL;
7534	struct buffer_head *gd_bh = NULL;
7535	struct ocfs2_dinode *main_bm;
7536	struct ocfs2_group_desc *gd = NULL;
7537
7538	start = range->start >> osb->s_clustersize_bits;
7539	len = range->len >> osb->s_clustersize_bits;
7540	minlen = range->minlen >> osb->s_clustersize_bits;
 
7541
7542	if (minlen >= osb->bitmap_cpg || range->len < sb->s_blocksize)
7543		return -EINVAL;
 
 
7544
7545	trace_ocfs2_trim_mainbm(start, len, minlen);
 
7546
7547next_group:
7548	main_bm_inode = ocfs2_get_system_file_inode(osb,
7549						    GLOBAL_BITMAP_SYSTEM_INODE,
7550						    OCFS2_INVALID_SLOT);
7551	if (!main_bm_inode) {
7552		ret = -EIO;
7553		mlog_errno(ret);
7554		goto out;
7555	}
7556
7557	inode_lock(main_bm_inode);
7558
7559	ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 0);
7560	if (ret < 0) {
7561		mlog_errno(ret);
7562		goto out_mutex;
7563	}
7564	main_bm = (struct ocfs2_dinode *)main_bm_bh->b_data;
7565
7566	/*
7567	 * Do some check before trim the first group.
7568	 */
7569	if (!group) {
7570		if (start >= le32_to_cpu(main_bm->i_clusters)) {
7571			ret = -EINVAL;
7572			goto out_unlock;
7573		}
7574
7575		if (start + len > le32_to_cpu(main_bm->i_clusters))
7576			len = le32_to_cpu(main_bm->i_clusters) - start;
7577
7578		/*
7579		 * Determine first and last group to examine based on
7580		 * start and len
7581		 */
7582		first_group = ocfs2_which_cluster_group(main_bm_inode, start);
7583		if (first_group == osb->first_cluster_group_blkno)
7584			first_bit = start;
7585		else
7586			first_bit = start - ocfs2_blocks_to_clusters(sb,
7587								first_group);
7588		last_group = ocfs2_which_cluster_group(main_bm_inode,
7589						       start + len - 1);
7590		group = first_group;
7591	}
7592
7593	do {
 
 
 
 
 
 
 
 
 
7594		if (first_bit + len >= osb->bitmap_cpg)
7595			last_bit = osb->bitmap_cpg;
7596		else
7597			last_bit = first_bit + len;
7598
7599		ret = ocfs2_read_group_descriptor(main_bm_inode,
7600						  main_bm, group,
7601						  &gd_bh);
7602		if (ret < 0) {
7603			mlog_errno(ret);
7604			break;
7605		}
7606
7607		gd = (struct ocfs2_group_desc *)gd_bh->b_data;
7608		cnt = ocfs2_trim_group(sb, gd, group,
7609				       first_bit, last_bit, minlen);
7610		brelse(gd_bh);
7611		gd_bh = NULL;
7612		if (cnt < 0) {
7613			ret = cnt;
7614			mlog_errno(ret);
7615			break;
7616		}
7617
7618		trimmed += cnt;
7619		len -= osb->bitmap_cpg - first_bit;
7620		first_bit = 0;
7621		if (group == osb->first_cluster_group_blkno)
7622			group = ocfs2_clusters_to_blocks(sb, osb->bitmap_cpg);
7623		else
7624			group += ocfs2_clusters_to_blocks(sb, osb->bitmap_cpg);
7625	} while (0);
7626
7627out_unlock:
7628	ocfs2_inode_unlock(main_bm_inode, 0);
7629	brelse(main_bm_bh);
7630	main_bm_bh = NULL;
7631out_mutex:
7632	inode_unlock(main_bm_inode);
7633	iput(main_bm_inode);
7634
7635	/*
7636	 * If all the groups trim are not done or failed, but we should release
7637	 * main_bm related locks for avoiding the current IO starve, then go to
7638	 * trim the next group
7639	 */
7640	if (ret >= 0 && group <= last_group) {
7641		cond_resched();
7642		goto next_group;
7643	}
7644out:
7645	range->len = trimmed * sb->s_blocksize;
7646	return ret;
7647}
7648
7649int ocfs2_trim_fs(struct super_block *sb, struct fstrim_range *range)
7650{
7651	int ret;
7652	struct ocfs2_super *osb = OCFS2_SB(sb);
7653	struct ocfs2_trim_fs_info info, *pinfo = NULL;
7654
7655	ocfs2_trim_fs_lock_res_init(osb);
7656
7657	trace_ocfs2_trim_fs(range->start, range->len, range->minlen);
7658
7659	ret = ocfs2_trim_fs_lock(osb, NULL, 1);
7660	if (ret < 0) {
7661		if (ret != -EAGAIN) {
7662			mlog_errno(ret);
7663			ocfs2_trim_fs_lock_res_uninit(osb);
7664			return ret;
7665		}
7666
7667		mlog(ML_NOTICE, "Wait for trim on device (%s) to "
7668		     "finish, which is running from another node.\n",
7669		     osb->dev_str);
7670		ret = ocfs2_trim_fs_lock(osb, &info, 0);
7671		if (ret < 0) {
7672			mlog_errno(ret);
7673			ocfs2_trim_fs_lock_res_uninit(osb);
7674			return ret;
7675		}
7676
7677		if (info.tf_valid && info.tf_success &&
7678		    info.tf_start == range->start &&
7679		    info.tf_len == range->len &&
7680		    info.tf_minlen == range->minlen) {
7681			/* Avoid sending duplicated trim to a shared device */
7682			mlog(ML_NOTICE, "The same trim on device (%s) was "
7683			     "just done from node (%u), return.\n",
7684			     osb->dev_str, info.tf_nodenum);
7685			range->len = info.tf_trimlen;
7686			goto out;
7687		}
7688	}
7689
7690	info.tf_nodenum = osb->node_num;
7691	info.tf_start = range->start;
7692	info.tf_len = range->len;
7693	info.tf_minlen = range->minlen;
7694
7695	ret = ocfs2_trim_mainbm(sb, range);
7696
7697	info.tf_trimlen = range->len;
7698	info.tf_success = (ret < 0 ? 0 : 1);
7699	pinfo = &info;
7700out:
7701	ocfs2_trim_fs_unlock(osb, pinfo);
7702	ocfs2_trim_fs_lock_res_uninit(osb);
7703	return ret;
7704}