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v5.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/* -*- mode: c; c-basic-offset: 8; -*-
   3 * vim: noexpandtab sw=8 ts=8 sts=0:
   4 *
   5 * move_extents.c
   6 *
   7 * Copyright (C) 2011 Oracle.  All rights reserved.
   8 */
   9#include <linux/fs.h>
  10#include <linux/types.h>
  11#include <linux/mount.h>
  12#include <linux/swap.h>
  13
  14#include <cluster/masklog.h>
  15
  16#include "ocfs2.h"
  17#include "ocfs2_ioctl.h"
  18
  19#include "alloc.h"
  20#include "localalloc.h"
  21#include "aops.h"
  22#include "dlmglue.h"
  23#include "extent_map.h"
  24#include "inode.h"
  25#include "journal.h"
  26#include "suballoc.h"
  27#include "uptodate.h"
  28#include "super.h"
  29#include "dir.h"
  30#include "buffer_head_io.h"
  31#include "sysfile.h"
  32#include "refcounttree.h"
  33#include "move_extents.h"
  34
  35struct ocfs2_move_extents_context {
  36	struct inode *inode;
  37	struct file *file;
  38	int auto_defrag;
  39	int partial;
  40	int credits;
  41	u32 new_phys_cpos;
  42	u32 clusters_moved;
  43	u64 refcount_loc;
  44	struct ocfs2_move_extents *range;
  45	struct ocfs2_extent_tree et;
  46	struct ocfs2_alloc_context *meta_ac;
  47	struct ocfs2_alloc_context *data_ac;
  48	struct ocfs2_cached_dealloc_ctxt dealloc;
  49};
  50
  51static int __ocfs2_move_extent(handle_t *handle,
  52			       struct ocfs2_move_extents_context *context,
  53			       u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
  54			       int ext_flags)
  55{
  56	int ret = 0, index;
  57	struct inode *inode = context->inode;
  58	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  59	struct ocfs2_extent_rec *rec, replace_rec;
  60	struct ocfs2_path *path = NULL;
  61	struct ocfs2_extent_list *el;
  62	u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
  63	u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
  64
  65	ret = ocfs2_duplicate_clusters_by_page(handle, inode, cpos,
  66					       p_cpos, new_p_cpos, len);
  67	if (ret) {
  68		mlog_errno(ret);
  69		goto out;
  70	}
  71
  72	memset(&replace_rec, 0, sizeof(replace_rec));
  73	replace_rec.e_cpos = cpu_to_le32(cpos);
  74	replace_rec.e_leaf_clusters = cpu_to_le16(len);
  75	replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
  76								   new_p_cpos));
  77
  78	path = ocfs2_new_path_from_et(&context->et);
  79	if (!path) {
  80		ret = -ENOMEM;
  81		mlog_errno(ret);
  82		goto out;
  83	}
  84
  85	ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
  86	if (ret) {
  87		mlog_errno(ret);
  88		goto out;
  89	}
  90
  91	el = path_leaf_el(path);
  92
  93	index = ocfs2_search_extent_list(el, cpos);
  94	if (index == -1) {
  95		ret = ocfs2_error(inode->i_sb,
  96				  "Inode %llu has an extent at cpos %u which can no longer be found\n",
  97				  (unsigned long long)ino, cpos);
  98		goto out;
  99	}
 100
 101	rec = &el->l_recs[index];
 102
 103	BUG_ON(ext_flags != rec->e_flags);
 104	/*
 105	 * after moving/defraging to new location, the extent is not going
 106	 * to be refcounted anymore.
 107	 */
 108	replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
 109
 110	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode),
 111				      context->et.et_root_bh,
 112				      OCFS2_JOURNAL_ACCESS_WRITE);
 113	if (ret) {
 114		mlog_errno(ret);
 115		goto out;
 116	}
 117
 118	ret = ocfs2_split_extent(handle, &context->et, path, index,
 119				 &replace_rec, context->meta_ac,
 120				 &context->dealloc);
 121	if (ret) {
 122		mlog_errno(ret);
 123		goto out;
 124	}
 125
 126	ocfs2_journal_dirty(handle, context->et.et_root_bh);
 127
 128	context->new_phys_cpos = new_p_cpos;
 129
 130	/*
 131	 * need I to append truncate log for old clusters?
 132	 */
 133	if (old_blkno) {
 134		if (ext_flags & OCFS2_EXT_REFCOUNTED)
 135			ret = ocfs2_decrease_refcount(inode, handle,
 136					ocfs2_blocks_to_clusters(osb->sb,
 137								 old_blkno),
 138					len, context->meta_ac,
 139					&context->dealloc, 1);
 140		else
 141			ret = ocfs2_truncate_log_append(osb, handle,
 142							old_blkno, len);
 143	}
 144
 145	ocfs2_update_inode_fsync_trans(handle, inode, 0);
 146out:
 147	ocfs2_free_path(path);
 148	return ret;
 149}
 150
 151/*
 152 * lock allocator, and reserve appropriate number of bits for
 153 * meta blocks.
 154 */
 155static int ocfs2_lock_meta_allocator_move_extents(struct inode *inode,
 156					struct ocfs2_extent_tree *et,
 157					u32 clusters_to_move,
 158					u32 extents_to_split,
 159					struct ocfs2_alloc_context **meta_ac,
 160					int extra_blocks,
 161					int *credits)
 162{
 163	int ret, num_free_extents;
 164	unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
 165	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 166
 167	num_free_extents = ocfs2_num_free_extents(et);
 168	if (num_free_extents < 0) {
 169		ret = num_free_extents;
 170		mlog_errno(ret);
 171		goto out;
 172	}
 173
 174	if (!num_free_extents ||
 175	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
 176		extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
 177
 178	ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
 179	if (ret) {
 180		mlog_errno(ret);
 181		goto out;
 182	}
 183
 184
 185	*credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el);
 186
 187	mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
 188	     extra_blocks, clusters_to_move, *credits);
 189out:
 190	if (ret) {
 191		if (*meta_ac) {
 192			ocfs2_free_alloc_context(*meta_ac);
 193			*meta_ac = NULL;
 194		}
 195	}
 196
 197	return ret;
 198}
 199
 200/*
 201 * Using one journal handle to guarantee the data consistency in case
 202 * crash happens anywhere.
 203 *
 204 *  XXX: defrag can end up with finishing partial extent as requested,
 205 * due to not enough contiguous clusters can be found in allocator.
 206 */
 207static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
 208			       u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
 209{
 210	int ret, credits = 0, extra_blocks = 0, partial = context->partial;
 211	handle_t *handle;
 212	struct inode *inode = context->inode;
 213	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 214	struct inode *tl_inode = osb->osb_tl_inode;
 215	struct ocfs2_refcount_tree *ref_tree = NULL;
 216	u32 new_phys_cpos, new_len;
 217	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
 218	int need_free = 0;
 219
 220	if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
 221		BUG_ON(!ocfs2_is_refcount_inode(inode));
 222		BUG_ON(!context->refcount_loc);
 223
 224		ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
 225					       &ref_tree, NULL);
 226		if (ret) {
 227			mlog_errno(ret);
 228			return ret;
 229		}
 230
 231		ret = ocfs2_prepare_refcount_change_for_del(inode,
 232							context->refcount_loc,
 233							phys_blkno,
 234							*len,
 235							&credits,
 236							&extra_blocks);
 237		if (ret) {
 238			mlog_errno(ret);
 239			goto out;
 240		}
 241	}
 242
 243	ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
 244						*len, 1,
 245						&context->meta_ac,
 246						extra_blocks, &credits);
 247	if (ret) {
 248		mlog_errno(ret);
 249		goto out;
 250	}
 251
 252	/*
 253	 * should be using allocation reservation strategy there?
 254	 *
 255	 * if (context->data_ac)
 256	 *	context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
 257	 */
 258
 259	inode_lock(tl_inode);
 260
 261	if (ocfs2_truncate_log_needs_flush(osb)) {
 262		ret = __ocfs2_flush_truncate_log(osb);
 263		if (ret < 0) {
 264			mlog_errno(ret);
 265			goto out_unlock_mutex;
 266		}
 267	}
 268
 269	/*
 270	 * Make sure ocfs2_reserve_cluster is called after
 271	 * __ocfs2_flush_truncate_log, otherwise, dead lock may happen.
 272	 *
 273	 * If ocfs2_reserve_cluster is called
 274	 * before __ocfs2_flush_truncate_log, dead lock on global bitmap
 275	 * may happen.
 276	 *
 277	 */
 278	ret = ocfs2_reserve_clusters(osb, *len, &context->data_ac);
 279	if (ret) {
 280		mlog_errno(ret);
 281		goto out_unlock_mutex;
 282	}
 283
 284	handle = ocfs2_start_trans(osb, credits);
 285	if (IS_ERR(handle)) {
 286		ret = PTR_ERR(handle);
 287		mlog_errno(ret);
 288		goto out_unlock_mutex;
 289	}
 290
 291	ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
 292				     &new_phys_cpos, &new_len);
 293	if (ret) {
 294		mlog_errno(ret);
 295		goto out_commit;
 296	}
 297
 298	/*
 299	 * allowing partial extent moving is kind of 'pros and cons', it makes
 300	 * whole defragmentation less likely to fail, on the contrary, the bad
 301	 * thing is it may make the fs even more fragmented after moving, let
 302	 * userspace make a good decision here.
 303	 */
 304	if (new_len != *len) {
 305		mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
 306		if (!partial) {
 307			context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
 308			ret = -ENOSPC;
 309			need_free = 1;
 310			goto out_commit;
 311		}
 312	}
 313
 314	mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
 315	     phys_cpos, new_phys_cpos);
 316
 317	ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
 318				  new_phys_cpos, ext_flags);
 319	if (ret)
 320		mlog_errno(ret);
 321
 322	if (partial && (new_len != *len))
 323		*len = new_len;
 324
 325	/*
 326	 * Here we should write the new page out first if we are
 327	 * in write-back mode.
 328	 */
 329	ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
 330	if (ret)
 331		mlog_errno(ret);
 332
 333out_commit:
 334	if (need_free && context->data_ac) {
 335		struct ocfs2_alloc_context *data_ac = context->data_ac;
 336
 337		if (context->data_ac->ac_which == OCFS2_AC_USE_LOCAL)
 338			ocfs2_free_local_alloc_bits(osb, handle, data_ac,
 339					new_phys_cpos, new_len);
 340		else
 341			ocfs2_free_clusters(handle,
 342					data_ac->ac_inode,
 343					data_ac->ac_bh,
 344					ocfs2_clusters_to_blocks(osb->sb, new_phys_cpos),
 345					new_len);
 346	}
 347
 348	ocfs2_commit_trans(osb, handle);
 349
 350out_unlock_mutex:
 351	inode_unlock(tl_inode);
 352
 353	if (context->data_ac) {
 354		ocfs2_free_alloc_context(context->data_ac);
 355		context->data_ac = NULL;
 356	}
 357
 358	if (context->meta_ac) {
 359		ocfs2_free_alloc_context(context->meta_ac);
 360		context->meta_ac = NULL;
 361	}
 362
 363out:
 364	if (ref_tree)
 365		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
 366
 367	return ret;
 368}
 369
 370/*
 371 * find the victim alloc group, where #blkno fits.
 372 */
 373static int ocfs2_find_victim_alloc_group(struct inode *inode,
 374					 u64 vict_blkno,
 375					 int type, int slot,
 376					 int *vict_bit,
 377					 struct buffer_head **ret_bh)
 378{
 379	int ret, i, bits_per_unit = 0;
 380	u64 blkno;
 381	char namebuf[40];
 382
 383	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 384	struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
 385	struct ocfs2_chain_list *cl;
 386	struct ocfs2_chain_rec *rec;
 387	struct ocfs2_dinode *ac_dinode;
 388	struct ocfs2_group_desc *bg;
 389
 390	ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
 391	ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
 392					 strlen(namebuf), &blkno);
 393	if (ret) {
 394		ret = -ENOENT;
 395		goto out;
 396	}
 397
 398	ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
 399	if (ret) {
 400		mlog_errno(ret);
 401		goto out;
 402	}
 403
 404	ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
 405	cl = &(ac_dinode->id2.i_chain);
 406	rec = &(cl->cl_recs[0]);
 407
 408	if (type == GLOBAL_BITMAP_SYSTEM_INODE)
 409		bits_per_unit = osb->s_clustersize_bits -
 410					inode->i_sb->s_blocksize_bits;
 411	/*
 412	 * 'vict_blkno' was out of the valid range.
 413	 */
 414	if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
 415	    (vict_blkno >= ((u64)le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
 416				bits_per_unit))) {
 417		ret = -EINVAL;
 418		goto out;
 419	}
 420
 421	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
 422
 423		rec = &(cl->cl_recs[i]);
 424		if (!rec)
 425			continue;
 426
 427		bg = NULL;
 428
 429		do {
 430			if (!bg)
 431				blkno = le64_to_cpu(rec->c_blkno);
 432			else
 433				blkno = le64_to_cpu(bg->bg_next_group);
 434
 435			if (gd_bh) {
 436				brelse(gd_bh);
 437				gd_bh = NULL;
 438			}
 439
 440			ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
 441			if (ret) {
 442				mlog_errno(ret);
 443				goto out;
 444			}
 445
 446			bg = (struct ocfs2_group_desc *)gd_bh->b_data;
 447
 448			if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
 449						le16_to_cpu(bg->bg_bits))) {
 450
 451				*ret_bh = gd_bh;
 452				*vict_bit = (vict_blkno - blkno) >>
 453							bits_per_unit;
 454				mlog(0, "find the victim group: #%llu, "
 455				     "total_bits: %u, vict_bit: %u\n",
 456				     blkno, le16_to_cpu(bg->bg_bits),
 457				     *vict_bit);
 458				goto out;
 459			}
 460
 461		} while (le64_to_cpu(bg->bg_next_group));
 462	}
 463
 464	ret = -EINVAL;
 465out:
 466	brelse(ac_bh);
 467
 468	/*
 469	 * caller has to release the gd_bh properly.
 470	 */
 471	return ret;
 472}
 473
 474/*
 475 * XXX: helper to validate and adjust moving goal.
 476 */
 477static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
 478					       struct ocfs2_move_extents *range)
 479{
 480	int ret, goal_bit = 0;
 481
 482	struct buffer_head *gd_bh = NULL;
 483	struct ocfs2_group_desc *bg;
 484	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 485	int c_to_b = 1 << (osb->s_clustersize_bits -
 486					inode->i_sb->s_blocksize_bits);
 487
 488	/*
 489	 * make goal become cluster aligned.
 490	 */
 491	range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
 492						      range->me_goal);
 493	/*
 494	 * validate goal sits within global_bitmap, and return the victim
 495	 * group desc
 496	 */
 497	ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
 498					    GLOBAL_BITMAP_SYSTEM_INODE,
 499					    OCFS2_INVALID_SLOT,
 500					    &goal_bit, &gd_bh);
 501	if (ret)
 502		goto out;
 503
 504	bg = (struct ocfs2_group_desc *)gd_bh->b_data;
 505
 506	/*
 507	 * moving goal is not allowd to start with a group desc blok(#0 blk)
 508	 * let's compromise to the latter cluster.
 509	 */
 510	if (range->me_goal == le64_to_cpu(bg->bg_blkno))
 511		range->me_goal += c_to_b;
 512
 513	/*
 514	 * movement is not gonna cross two groups.
 515	 */
 516	if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
 517								range->me_len) {
 518		ret = -EINVAL;
 519		goto out;
 520	}
 521	/*
 522	 * more exact validations/adjustments will be performed later during
 523	 * moving operation for each extent range.
 524	 */
 525	mlog(0, "extents get ready to be moved to #%llu block\n",
 526	     range->me_goal);
 527
 528out:
 529	brelse(gd_bh);
 530
 531	return ret;
 532}
 533
 534static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
 535				    int *goal_bit, u32 move_len, u32 max_hop,
 536				    u32 *phys_cpos)
 537{
 538	int i, used, last_free_bits = 0, base_bit = *goal_bit;
 539	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 540	u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
 541						 le64_to_cpu(gd->bg_blkno));
 542
 543	for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
 544
 545		used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
 546		if (used) {
 547			/*
 548			 * we even tried searching the free chunk by jumping
 549			 * a 'max_hop' distance, but still failed.
 550			 */
 551			if ((i - base_bit) > max_hop) {
 552				*phys_cpos = 0;
 553				break;
 554			}
 555
 556			if (last_free_bits)
 557				last_free_bits = 0;
 558
 559			continue;
 560		} else
 561			last_free_bits++;
 562
 563		if (last_free_bits == move_len) {
 
 564			*goal_bit = i;
 565			*phys_cpos = base_cpos + i;
 566			break;
 567		}
 568	}
 569
 570	mlog(0, "found phys_cpos: %u to fit the wanted moving.\n", *phys_cpos);
 571}
 572
 573static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
 574			     u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
 575			     u32 len, int ext_flags)
 576{
 577	int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
 578	handle_t *handle;
 579	struct inode *inode = context->inode;
 580	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 581	struct inode *tl_inode = osb->osb_tl_inode;
 582	struct inode *gb_inode = NULL;
 583	struct buffer_head *gb_bh = NULL;
 584	struct buffer_head *gd_bh = NULL;
 585	struct ocfs2_group_desc *gd;
 586	struct ocfs2_refcount_tree *ref_tree = NULL;
 587	u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
 588						    context->range->me_threshold);
 589	u64 phys_blkno, new_phys_blkno;
 590
 591	phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
 592
 593	if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
 594		BUG_ON(!ocfs2_is_refcount_inode(inode));
 595		BUG_ON(!context->refcount_loc);
 596
 597		ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
 598					       &ref_tree, NULL);
 599		if (ret) {
 600			mlog_errno(ret);
 601			return ret;
 602		}
 603
 604		ret = ocfs2_prepare_refcount_change_for_del(inode,
 605							context->refcount_loc,
 606							phys_blkno,
 607							len,
 608							&credits,
 609							&extra_blocks);
 610		if (ret) {
 611			mlog_errno(ret);
 612			goto out;
 613		}
 614	}
 615
 616	ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
 617						len, 1,
 618						&context->meta_ac,
 619						extra_blocks, &credits);
 620	if (ret) {
 621		mlog_errno(ret);
 622		goto out;
 623	}
 624
 625	/*
 626	 * need to count 2 extra credits for global_bitmap inode and
 627	 * group descriptor.
 628	 */
 629	credits += OCFS2_INODE_UPDATE_CREDITS + 1;
 630
 631	/*
 632	 * ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
 633	 * logic, while we still need to lock the global_bitmap.
 634	 */
 635	gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
 636					       OCFS2_INVALID_SLOT);
 637	if (!gb_inode) {
 638		mlog(ML_ERROR, "unable to get global_bitmap inode\n");
 639		ret = -EIO;
 640		goto out;
 641	}
 642
 643	inode_lock(gb_inode);
 644
 645	ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
 646	if (ret) {
 647		mlog_errno(ret);
 648		goto out_unlock_gb_mutex;
 649	}
 650
 651	inode_lock(tl_inode);
 652
 653	handle = ocfs2_start_trans(osb, credits);
 654	if (IS_ERR(handle)) {
 655		ret = PTR_ERR(handle);
 656		mlog_errno(ret);
 657		goto out_unlock_tl_inode;
 658	}
 659
 660	new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
 661	ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
 662					    GLOBAL_BITMAP_SYSTEM_INODE,
 663					    OCFS2_INVALID_SLOT,
 664					    &goal_bit, &gd_bh);
 665	if (ret) {
 666		mlog_errno(ret);
 667		goto out_commit;
 668	}
 669
 670	/*
 671	 * probe the victim cluster group to find a proper
 672	 * region to fit wanted movement, it even will perfrom
 673	 * a best-effort attempt by compromising to a threshold
 674	 * around the goal.
 675	 */
 676	ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
 677				new_phys_cpos);
 678	if (!*new_phys_cpos) {
 679		ret = -ENOSPC;
 680		goto out_commit;
 681	}
 682
 683	ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
 684				  *new_phys_cpos, ext_flags);
 685	if (ret) {
 686		mlog_errno(ret);
 687		goto out_commit;
 688	}
 689
 690	gd = (struct ocfs2_group_desc *)gd_bh->b_data;
 691	ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
 692					       le16_to_cpu(gd->bg_chain));
 693	if (ret) {
 694		mlog_errno(ret);
 695		goto out_commit;
 696	}
 697
 698	ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
 699					 goal_bit, len);
 700	if (ret) {
 701		ocfs2_rollback_alloc_dinode_counts(gb_inode, gb_bh, len,
 702					       le16_to_cpu(gd->bg_chain));
 703		mlog_errno(ret);
 704	}
 705
 706	/*
 707	 * Here we should write the new page out first if we are
 708	 * in write-back mode.
 709	 */
 710	ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
 711	if (ret)
 712		mlog_errno(ret);
 713
 714out_commit:
 715	ocfs2_commit_trans(osb, handle);
 716	brelse(gd_bh);
 717
 718out_unlock_tl_inode:
 719	inode_unlock(tl_inode);
 720
 721	ocfs2_inode_unlock(gb_inode, 1);
 722out_unlock_gb_mutex:
 723	inode_unlock(gb_inode);
 724	brelse(gb_bh);
 725	iput(gb_inode);
 726
 727out:
 728	if (context->meta_ac) {
 729		ocfs2_free_alloc_context(context->meta_ac);
 730		context->meta_ac = NULL;
 731	}
 732
 733	if (ref_tree)
 734		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
 735
 736	return ret;
 737}
 738
 739/*
 740 * Helper to calculate the defraging length in one run according to threshold.
 741 */
 742static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
 743					 u32 threshold, int *skip)
 744{
 745	if ((*alloc_size + *len_defraged) < threshold) {
 746		/*
 747		 * proceed defragmentation until we meet the thresh
 748		 */
 749		*len_defraged += *alloc_size;
 750	} else if (*len_defraged == 0) {
 751		/*
 752		 * XXX: skip a large extent.
 753		 */
 754		*skip = 1;
 755	} else {
 756		/*
 757		 * split this extent to coalesce with former pieces as
 758		 * to reach the threshold.
 759		 *
 760		 * we're done here with one cycle of defragmentation
 761		 * in a size of 'thresh', resetting 'len_defraged'
 762		 * forces a new defragmentation.
 763		 */
 764		*alloc_size = threshold - *len_defraged;
 765		*len_defraged = 0;
 766	}
 767}
 768
 769static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
 770				struct ocfs2_move_extents_context *context)
 771{
 772	int ret = 0, flags, do_defrag, skip = 0;
 773	u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
 774	u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
 775
 776	struct inode *inode = context->inode;
 777	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 778	struct ocfs2_move_extents *range = context->range;
 779	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 780
 781	if ((i_size_read(inode) == 0) || (range->me_len == 0))
 782		return 0;
 783
 784	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 785		return 0;
 786
 787	context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
 788
 789	ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
 790	ocfs2_init_dealloc_ctxt(&context->dealloc);
 791
 792	/*
 793	 * TO-DO XXX:
 794	 *
 795	 * - xattr extents.
 796	 */
 797
 798	do_defrag = context->auto_defrag;
 799
 800	/*
 801	 * extents moving happens in unit of clusters, for the sake
 802	 * of simplicity, we may ignore two clusters where 'byte_start'
 803	 * and 'byte_start + len' were within.
 804	 */
 805	move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
 806	len_to_move = (range->me_start + range->me_len) >>
 807						osb->s_clustersize_bits;
 808	if (len_to_move >= move_start)
 809		len_to_move -= move_start;
 810	else
 811		len_to_move = 0;
 812
 813	if (do_defrag) {
 814		defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
 815		if (defrag_thresh <= 1)
 816			goto done;
 817	} else
 818		new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
 819							 range->me_goal);
 820
 821	mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
 822	     "thresh: %u\n",
 823	     (unsigned long long)OCFS2_I(inode)->ip_blkno,
 824	     (unsigned long long)range->me_start,
 825	     (unsigned long long)range->me_len,
 826	     move_start, len_to_move, defrag_thresh);
 827
 828	cpos = move_start;
 829	while (len_to_move) {
 830		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
 831					 &flags);
 832		if (ret) {
 833			mlog_errno(ret);
 834			goto out;
 835		}
 836
 837		if (alloc_size > len_to_move)
 838			alloc_size = len_to_move;
 839
 840		/*
 841		 * XXX: how to deal with a hole:
 842		 *
 843		 * - skip the hole of course
 844		 * - force a new defragmentation
 845		 */
 846		if (!phys_cpos) {
 847			if (do_defrag)
 848				len_defraged = 0;
 849
 850			goto next;
 851		}
 852
 853		if (do_defrag) {
 854			ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
 855						     defrag_thresh, &skip);
 856			/*
 857			 * skip large extents
 858			 */
 859			if (skip) {
 860				skip = 0;
 861				goto next;
 862			}
 863
 864			mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
 865			     "alloc_size: %u, len_defraged: %u\n",
 866			     cpos, phys_cpos, alloc_size, len_defraged);
 867
 868			ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
 869						  &alloc_size, flags);
 870		} else {
 871			ret = ocfs2_move_extent(context, cpos, phys_cpos,
 872						&new_phys_cpos, alloc_size,
 873						flags);
 874
 875			new_phys_cpos += alloc_size;
 876		}
 877
 878		if (ret < 0) {
 879			mlog_errno(ret);
 880			goto out;
 881		}
 882
 883		context->clusters_moved += alloc_size;
 884next:
 885		cpos += alloc_size;
 886		len_to_move -= alloc_size;
 887	}
 888
 889done:
 890	range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
 891
 892out:
 893	range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
 894						      context->clusters_moved);
 895	range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
 896						       context->new_phys_cpos);
 897
 898	ocfs2_schedule_truncate_log_flush(osb, 1);
 899	ocfs2_run_deallocs(osb, &context->dealloc);
 900
 901	return ret;
 902}
 903
 904static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
 905{
 906	int status;
 907	handle_t *handle;
 908	struct inode *inode = context->inode;
 909	struct ocfs2_dinode *di;
 910	struct buffer_head *di_bh = NULL;
 911	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 912
 913	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
 914		return -EROFS;
 915
 916	inode_lock(inode);
 917
 918	/*
 919	 * This prevents concurrent writes from other nodes
 920	 */
 921	status = ocfs2_rw_lock(inode, 1);
 922	if (status) {
 923		mlog_errno(status);
 924		goto out;
 925	}
 926
 927	status = ocfs2_inode_lock(inode, &di_bh, 1);
 928	if (status) {
 929		mlog_errno(status);
 930		goto out_rw_unlock;
 931	}
 932
 933	/*
 934	 * rememer ip_xattr_sem also needs to be held if necessary
 935	 */
 936	down_write(&OCFS2_I(inode)->ip_alloc_sem);
 937
 938	status = __ocfs2_move_extents_range(di_bh, context);
 939
 940	up_write(&OCFS2_I(inode)->ip_alloc_sem);
 941	if (status) {
 942		mlog_errno(status);
 943		goto out_inode_unlock;
 944	}
 945
 946	/*
 947	 * We update ctime for these changes
 948	 */
 949	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
 950	if (IS_ERR(handle)) {
 951		status = PTR_ERR(handle);
 952		mlog_errno(status);
 953		goto out_inode_unlock;
 954	}
 955
 956	status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
 957					 OCFS2_JOURNAL_ACCESS_WRITE);
 958	if (status) {
 959		mlog_errno(status);
 960		goto out_commit;
 961	}
 962
 963	di = (struct ocfs2_dinode *)di_bh->b_data;
 964	inode->i_ctime = current_time(inode);
 965	di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 966	di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 967	ocfs2_update_inode_fsync_trans(handle, inode, 0);
 968
 969	ocfs2_journal_dirty(handle, di_bh);
 970
 971out_commit:
 972	ocfs2_commit_trans(osb, handle);
 973
 974out_inode_unlock:
 975	brelse(di_bh);
 976	ocfs2_inode_unlock(inode, 1);
 977out_rw_unlock:
 978	ocfs2_rw_unlock(inode, 1);
 979out:
 980	inode_unlock(inode);
 981
 982	return status;
 983}
 984
 985int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
 986{
 987	int status;
 988
 989	struct inode *inode = file_inode(filp);
 990	struct ocfs2_move_extents range;
 991	struct ocfs2_move_extents_context *context;
 992
 993	if (!argp)
 994		return -EINVAL;
 995
 996	status = mnt_want_write_file(filp);
 997	if (status)
 998		return status;
 999
1000	if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE)) {
1001		status = -EPERM;
1002		goto out_drop;
1003	}
1004
1005	if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
1006		status = -EPERM;
1007		goto out_drop;
1008	}
1009
1010	context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
1011	if (!context) {
1012		status = -ENOMEM;
1013		mlog_errno(status);
1014		goto out_drop;
1015	}
1016
1017	context->inode = inode;
1018	context->file = filp;
1019
1020	if (copy_from_user(&range, argp, sizeof(range))) {
1021		status = -EFAULT;
1022		goto out_free;
1023	}
1024
1025	if (range.me_start > i_size_read(inode)) {
1026		status = -EINVAL;
1027		goto out_free;
1028	}
1029
1030	if (range.me_start + range.me_len > i_size_read(inode))
1031			range.me_len = i_size_read(inode) - range.me_start;
1032
1033	context->range = &range;
1034
 
 
 
 
 
 
 
 
 
 
 
1035	if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
1036		context->auto_defrag = 1;
1037		/*
1038		 * ok, the default theshold for the defragmentation
1039		 * is 1M, since our maximum clustersize was 1M also.
1040		 * any thought?
1041		 */
1042		if (!range.me_threshold)
1043			range.me_threshold = 1024 * 1024;
1044
1045		if (range.me_threshold > i_size_read(inode))
1046			range.me_threshold = i_size_read(inode);
1047
1048		if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
1049			context->partial = 1;
1050	} else {
1051		/*
1052		 * first best-effort attempt to validate and adjust the goal
1053		 * (physical address in block), while it can't guarantee later
1054		 * operation can succeed all the time since global_bitmap may
1055		 * change a bit over time.
1056		 */
1057
1058		status = ocfs2_validate_and_adjust_move_goal(inode, &range);
1059		if (status)
1060			goto out_copy;
1061	}
1062
1063	status = ocfs2_move_extents(context);
1064	if (status)
1065		mlog_errno(status);
1066out_copy:
1067	/*
1068	 * movement/defragmentation may end up being partially completed,
1069	 * that's the reason why we need to return userspace the finished
1070	 * length and new_offset even if failure happens somewhere.
1071	 */
1072	if (copy_to_user(argp, &range, sizeof(range)))
1073		status = -EFAULT;
1074
1075out_free:
1076	kfree(context);
1077out_drop:
1078	mnt_drop_write_file(filp);
1079
1080	return status;
1081}
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
 
 
   3 * move_extents.c
   4 *
   5 * Copyright (C) 2011 Oracle.  All rights reserved.
   6 */
   7#include <linux/fs.h>
   8#include <linux/types.h>
   9#include <linux/mount.h>
  10#include <linux/swap.h>
  11
  12#include <cluster/masklog.h>
  13
  14#include "ocfs2.h"
  15#include "ocfs2_ioctl.h"
  16
  17#include "alloc.h"
  18#include "localalloc.h"
  19#include "aops.h"
  20#include "dlmglue.h"
  21#include "extent_map.h"
  22#include "inode.h"
  23#include "journal.h"
  24#include "suballoc.h"
  25#include "uptodate.h"
  26#include "super.h"
  27#include "dir.h"
  28#include "buffer_head_io.h"
  29#include "sysfile.h"
  30#include "refcounttree.h"
  31#include "move_extents.h"
  32
  33struct ocfs2_move_extents_context {
  34	struct inode *inode;
  35	struct file *file;
  36	int auto_defrag;
  37	int partial;
  38	int credits;
  39	u32 new_phys_cpos;
  40	u32 clusters_moved;
  41	u64 refcount_loc;
  42	struct ocfs2_move_extents *range;
  43	struct ocfs2_extent_tree et;
  44	struct ocfs2_alloc_context *meta_ac;
  45	struct ocfs2_alloc_context *data_ac;
  46	struct ocfs2_cached_dealloc_ctxt dealloc;
  47};
  48
  49static int __ocfs2_move_extent(handle_t *handle,
  50			       struct ocfs2_move_extents_context *context,
  51			       u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
  52			       int ext_flags)
  53{
  54	int ret = 0, index;
  55	struct inode *inode = context->inode;
  56	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  57	struct ocfs2_extent_rec *rec, replace_rec;
  58	struct ocfs2_path *path = NULL;
  59	struct ocfs2_extent_list *el;
  60	u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
  61	u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
  62
  63	ret = ocfs2_duplicate_clusters_by_page(handle, inode, cpos,
  64					       p_cpos, new_p_cpos, len);
  65	if (ret) {
  66		mlog_errno(ret);
  67		goto out;
  68	}
  69
  70	memset(&replace_rec, 0, sizeof(replace_rec));
  71	replace_rec.e_cpos = cpu_to_le32(cpos);
  72	replace_rec.e_leaf_clusters = cpu_to_le16(len);
  73	replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
  74								   new_p_cpos));
  75
  76	path = ocfs2_new_path_from_et(&context->et);
  77	if (!path) {
  78		ret = -ENOMEM;
  79		mlog_errno(ret);
  80		goto out;
  81	}
  82
  83	ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
  84	if (ret) {
  85		mlog_errno(ret);
  86		goto out;
  87	}
  88
  89	el = path_leaf_el(path);
  90
  91	index = ocfs2_search_extent_list(el, cpos);
  92	if (index == -1) {
  93		ret = ocfs2_error(inode->i_sb,
  94				  "Inode %llu has an extent at cpos %u which can no longer be found\n",
  95				  (unsigned long long)ino, cpos);
  96		goto out;
  97	}
  98
  99	rec = &el->l_recs[index];
 100
 101	BUG_ON(ext_flags != rec->e_flags);
 102	/*
 103	 * after moving/defraging to new location, the extent is not going
 104	 * to be refcounted anymore.
 105	 */
 106	replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
 107
 
 
 
 
 
 
 
 
 108	ret = ocfs2_split_extent(handle, &context->et, path, index,
 109				 &replace_rec, context->meta_ac,
 110				 &context->dealloc);
 111	if (ret) {
 112		mlog_errno(ret);
 113		goto out;
 114	}
 115
 
 
 116	context->new_phys_cpos = new_p_cpos;
 117
 118	/*
 119	 * need I to append truncate log for old clusters?
 120	 */
 121	if (old_blkno) {
 122		if (ext_flags & OCFS2_EXT_REFCOUNTED)
 123			ret = ocfs2_decrease_refcount(inode, handle,
 124					ocfs2_blocks_to_clusters(osb->sb,
 125								 old_blkno),
 126					len, context->meta_ac,
 127					&context->dealloc, 1);
 128		else
 129			ret = ocfs2_truncate_log_append(osb, handle,
 130							old_blkno, len);
 131	}
 132
 133	ocfs2_update_inode_fsync_trans(handle, inode, 0);
 134out:
 135	ocfs2_free_path(path);
 136	return ret;
 137}
 138
 139/*
 140 * lock allocator, and reserve appropriate number of bits for
 141 * meta blocks.
 142 */
 143static int ocfs2_lock_meta_allocator_move_extents(struct inode *inode,
 144					struct ocfs2_extent_tree *et,
 145					u32 clusters_to_move,
 146					u32 extents_to_split,
 147					struct ocfs2_alloc_context **meta_ac,
 148					int extra_blocks,
 149					int *credits)
 150{
 151	int ret, num_free_extents;
 152	unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
 153	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 154
 155	num_free_extents = ocfs2_num_free_extents(et);
 156	if (num_free_extents < 0) {
 157		ret = num_free_extents;
 158		mlog_errno(ret);
 159		goto out;
 160	}
 161
 162	if (!num_free_extents ||
 163	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
 164		extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
 165
 166	ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
 167	if (ret) {
 168		mlog_errno(ret);
 169		goto out;
 170	}
 171
 172
 173	*credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el);
 174
 175	mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
 176	     extra_blocks, clusters_to_move, *credits);
 177out:
 178	if (ret) {
 179		if (*meta_ac) {
 180			ocfs2_free_alloc_context(*meta_ac);
 181			*meta_ac = NULL;
 182		}
 183	}
 184
 185	return ret;
 186}
 187
 188/*
 189 * Using one journal handle to guarantee the data consistency in case
 190 * crash happens anywhere.
 191 *
 192 *  XXX: defrag can end up with finishing partial extent as requested,
 193 * due to not enough contiguous clusters can be found in allocator.
 194 */
 195static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
 196			       u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
 197{
 198	int ret, credits = 0, extra_blocks = 0, partial = context->partial;
 199	handle_t *handle;
 200	struct inode *inode = context->inode;
 201	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 202	struct inode *tl_inode = osb->osb_tl_inode;
 203	struct ocfs2_refcount_tree *ref_tree = NULL;
 204	u32 new_phys_cpos, new_len;
 205	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
 206	int need_free = 0;
 207
 208	if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
 209		BUG_ON(!ocfs2_is_refcount_inode(inode));
 210		BUG_ON(!context->refcount_loc);
 211
 212		ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
 213					       &ref_tree, NULL);
 214		if (ret) {
 215			mlog_errno(ret);
 216			return ret;
 217		}
 218
 219		ret = ocfs2_prepare_refcount_change_for_del(inode,
 220							context->refcount_loc,
 221							phys_blkno,
 222							*len,
 223							&credits,
 224							&extra_blocks);
 225		if (ret) {
 226			mlog_errno(ret);
 227			goto out;
 228		}
 229	}
 230
 231	ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
 232						*len, 1,
 233						&context->meta_ac,
 234						extra_blocks, &credits);
 235	if (ret) {
 236		mlog_errno(ret);
 237		goto out;
 238	}
 239
 240	/*
 241	 * should be using allocation reservation strategy there?
 242	 *
 243	 * if (context->data_ac)
 244	 *	context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
 245	 */
 246
 247	inode_lock(tl_inode);
 248
 249	if (ocfs2_truncate_log_needs_flush(osb)) {
 250		ret = __ocfs2_flush_truncate_log(osb);
 251		if (ret < 0) {
 252			mlog_errno(ret);
 253			goto out_unlock_mutex;
 254		}
 255	}
 256
 257	/*
 258	 * Make sure ocfs2_reserve_cluster is called after
 259	 * __ocfs2_flush_truncate_log, otherwise, dead lock may happen.
 260	 *
 261	 * If ocfs2_reserve_cluster is called
 262	 * before __ocfs2_flush_truncate_log, dead lock on global bitmap
 263	 * may happen.
 264	 *
 265	 */
 266	ret = ocfs2_reserve_clusters(osb, *len, &context->data_ac);
 267	if (ret) {
 268		mlog_errno(ret);
 269		goto out_unlock_mutex;
 270	}
 271
 272	handle = ocfs2_start_trans(osb, credits);
 273	if (IS_ERR(handle)) {
 274		ret = PTR_ERR(handle);
 275		mlog_errno(ret);
 276		goto out_unlock_mutex;
 277	}
 278
 279	ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
 280				     &new_phys_cpos, &new_len);
 281	if (ret) {
 282		mlog_errno(ret);
 283		goto out_commit;
 284	}
 285
 286	/*
 287	 * allowing partial extent moving is kind of 'pros and cons', it makes
 288	 * whole defragmentation less likely to fail, on the contrary, the bad
 289	 * thing is it may make the fs even more fragmented after moving, let
 290	 * userspace make a good decision here.
 291	 */
 292	if (new_len != *len) {
 293		mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
 294		if (!partial) {
 295			context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
 296			ret = -ENOSPC;
 297			need_free = 1;
 298			goto out_commit;
 299		}
 300	}
 301
 302	mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
 303	     phys_cpos, new_phys_cpos);
 304
 305	ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
 306				  new_phys_cpos, ext_flags);
 307	if (ret)
 308		mlog_errno(ret);
 309
 310	if (partial && (new_len != *len))
 311		*len = new_len;
 312
 313	/*
 314	 * Here we should write the new page out first if we are
 315	 * in write-back mode.
 316	 */
 317	ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
 318	if (ret)
 319		mlog_errno(ret);
 320
 321out_commit:
 322	if (need_free && context->data_ac) {
 323		struct ocfs2_alloc_context *data_ac = context->data_ac;
 324
 325		if (context->data_ac->ac_which == OCFS2_AC_USE_LOCAL)
 326			ocfs2_free_local_alloc_bits(osb, handle, data_ac,
 327					new_phys_cpos, new_len);
 328		else
 329			ocfs2_free_clusters(handle,
 330					data_ac->ac_inode,
 331					data_ac->ac_bh,
 332					ocfs2_clusters_to_blocks(osb->sb, new_phys_cpos),
 333					new_len);
 334	}
 335
 336	ocfs2_commit_trans(osb, handle);
 337
 338out_unlock_mutex:
 339	inode_unlock(tl_inode);
 340
 341	if (context->data_ac) {
 342		ocfs2_free_alloc_context(context->data_ac);
 343		context->data_ac = NULL;
 344	}
 345
 346	if (context->meta_ac) {
 347		ocfs2_free_alloc_context(context->meta_ac);
 348		context->meta_ac = NULL;
 349	}
 350
 351out:
 352	if (ref_tree)
 353		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
 354
 355	return ret;
 356}
 357
 358/*
 359 * find the victim alloc group, where #blkno fits.
 360 */
 361static int ocfs2_find_victim_alloc_group(struct inode *inode,
 362					 u64 vict_blkno,
 363					 int type, int slot,
 364					 int *vict_bit,
 365					 struct buffer_head **ret_bh)
 366{
 367	int ret, i, bits_per_unit = 0;
 368	u64 blkno;
 369	char namebuf[40];
 370
 371	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 372	struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
 373	struct ocfs2_chain_list *cl;
 374	struct ocfs2_chain_rec *rec;
 375	struct ocfs2_dinode *ac_dinode;
 376	struct ocfs2_group_desc *bg;
 377
 378	ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
 379	ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
 380					 strlen(namebuf), &blkno);
 381	if (ret) {
 382		ret = -ENOENT;
 383		goto out;
 384	}
 385
 386	ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
 387	if (ret) {
 388		mlog_errno(ret);
 389		goto out;
 390	}
 391
 392	ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
 393	cl = &(ac_dinode->id2.i_chain);
 394	rec = &(cl->cl_recs[0]);
 395
 396	if (type == GLOBAL_BITMAP_SYSTEM_INODE)
 397		bits_per_unit = osb->s_clustersize_bits -
 398					inode->i_sb->s_blocksize_bits;
 399	/*
 400	 * 'vict_blkno' was out of the valid range.
 401	 */
 402	if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
 403	    (vict_blkno >= ((u64)le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
 404				bits_per_unit))) {
 405		ret = -EINVAL;
 406		goto out;
 407	}
 408
 409	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
 410
 411		rec = &(cl->cl_recs[i]);
 412		if (!rec)
 413			continue;
 414
 415		bg = NULL;
 416
 417		do {
 418			if (!bg)
 419				blkno = le64_to_cpu(rec->c_blkno);
 420			else
 421				blkno = le64_to_cpu(bg->bg_next_group);
 422
 423			if (gd_bh) {
 424				brelse(gd_bh);
 425				gd_bh = NULL;
 426			}
 427
 428			ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
 429			if (ret) {
 430				mlog_errno(ret);
 431				goto out;
 432			}
 433
 434			bg = (struct ocfs2_group_desc *)gd_bh->b_data;
 435
 436			if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
 437						(le16_to_cpu(bg->bg_bits) << bits_per_unit))) {
 438
 439				*ret_bh = gd_bh;
 440				*vict_bit = (vict_blkno - blkno) >>
 441							bits_per_unit;
 442				mlog(0, "find the victim group: #%llu, "
 443				     "total_bits: %u, vict_bit: %u\n",
 444				     blkno, le16_to_cpu(bg->bg_bits),
 445				     *vict_bit);
 446				goto out;
 447			}
 448
 449		} while (le64_to_cpu(bg->bg_next_group));
 450	}
 451
 452	ret = -EINVAL;
 453out:
 454	brelse(ac_bh);
 455
 456	/*
 457	 * caller has to release the gd_bh properly.
 458	 */
 459	return ret;
 460}
 461
 462/*
 463 * XXX: helper to validate and adjust moving goal.
 464 */
 465static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
 466					       struct ocfs2_move_extents *range)
 467{
 468	int ret, goal_bit = 0;
 469
 470	struct buffer_head *gd_bh = NULL;
 471	struct ocfs2_group_desc *bg;
 472	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 473	int c_to_b = 1 << (osb->s_clustersize_bits -
 474					inode->i_sb->s_blocksize_bits);
 475
 476	/*
 477	 * make goal become cluster aligned.
 478	 */
 479	range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
 480						      range->me_goal);
 481	/*
 482	 * validate goal sits within global_bitmap, and return the victim
 483	 * group desc
 484	 */
 485	ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
 486					    GLOBAL_BITMAP_SYSTEM_INODE,
 487					    OCFS2_INVALID_SLOT,
 488					    &goal_bit, &gd_bh);
 489	if (ret)
 490		goto out;
 491
 492	bg = (struct ocfs2_group_desc *)gd_bh->b_data;
 493
 494	/*
 495	 * moving goal is not allowd to start with a group desc blok(#0 blk)
 496	 * let's compromise to the latter cluster.
 497	 */
 498	if (range->me_goal == le64_to_cpu(bg->bg_blkno))
 499		range->me_goal += c_to_b;
 500
 501	/*
 502	 * movement is not gonna cross two groups.
 503	 */
 504	if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
 505								range->me_len) {
 506		ret = -EINVAL;
 507		goto out;
 508	}
 509	/*
 510	 * more exact validations/adjustments will be performed later during
 511	 * moving operation for each extent range.
 512	 */
 513	mlog(0, "extents get ready to be moved to #%llu block\n",
 514	     range->me_goal);
 515
 516out:
 517	brelse(gd_bh);
 518
 519	return ret;
 520}
 521
 522static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
 523				    int *goal_bit, u32 move_len, u32 max_hop,
 524				    u32 *phys_cpos)
 525{
 526	int i, used, last_free_bits = 0, base_bit = *goal_bit;
 527	struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 528	u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
 529						 le64_to_cpu(gd->bg_blkno));
 530
 531	for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
 532
 533		used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
 534		if (used) {
 535			/*
 536			 * we even tried searching the free chunk by jumping
 537			 * a 'max_hop' distance, but still failed.
 538			 */
 539			if ((i - base_bit) > max_hop) {
 540				*phys_cpos = 0;
 541				break;
 542			}
 543
 544			if (last_free_bits)
 545				last_free_bits = 0;
 546
 547			continue;
 548		} else
 549			last_free_bits++;
 550
 551		if (last_free_bits == move_len) {
 552			i -= move_len;
 553			*goal_bit = i;
 554			*phys_cpos = base_cpos + i;
 555			break;
 556		}
 557	}
 558
 559	mlog(0, "found phys_cpos: %u to fit the wanted moving.\n", *phys_cpos);
 560}
 561
 562static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
 563			     u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
 564			     u32 len, int ext_flags)
 565{
 566	int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
 567	handle_t *handle;
 568	struct inode *inode = context->inode;
 569	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 570	struct inode *tl_inode = osb->osb_tl_inode;
 571	struct inode *gb_inode = NULL;
 572	struct buffer_head *gb_bh = NULL;
 573	struct buffer_head *gd_bh = NULL;
 574	struct ocfs2_group_desc *gd;
 575	struct ocfs2_refcount_tree *ref_tree = NULL;
 576	u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
 577						    context->range->me_threshold);
 578	u64 phys_blkno, new_phys_blkno;
 579
 580	phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
 581
 582	if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
 583		BUG_ON(!ocfs2_is_refcount_inode(inode));
 584		BUG_ON(!context->refcount_loc);
 585
 586		ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
 587					       &ref_tree, NULL);
 588		if (ret) {
 589			mlog_errno(ret);
 590			return ret;
 591		}
 592
 593		ret = ocfs2_prepare_refcount_change_for_del(inode,
 594							context->refcount_loc,
 595							phys_blkno,
 596							len,
 597							&credits,
 598							&extra_blocks);
 599		if (ret) {
 600			mlog_errno(ret);
 601			goto out;
 602		}
 603	}
 604
 605	ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
 606						len, 1,
 607						&context->meta_ac,
 608						extra_blocks, &credits);
 609	if (ret) {
 610		mlog_errno(ret);
 611		goto out;
 612	}
 613
 614	/*
 615	 * need to count 2 extra credits for global_bitmap inode and
 616	 * group descriptor.
 617	 */
 618	credits += OCFS2_INODE_UPDATE_CREDITS + 1;
 619
 620	/*
 621	 * ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
 622	 * logic, while we still need to lock the global_bitmap.
 623	 */
 624	gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
 625					       OCFS2_INVALID_SLOT);
 626	if (!gb_inode) {
 627		mlog(ML_ERROR, "unable to get global_bitmap inode\n");
 628		ret = -EIO;
 629		goto out;
 630	}
 631
 632	inode_lock(gb_inode);
 633
 634	ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
 635	if (ret) {
 636		mlog_errno(ret);
 637		goto out_unlock_gb_mutex;
 638	}
 639
 640	inode_lock(tl_inode);
 641
 642	handle = ocfs2_start_trans(osb, credits);
 643	if (IS_ERR(handle)) {
 644		ret = PTR_ERR(handle);
 645		mlog_errno(ret);
 646		goto out_unlock_tl_inode;
 647	}
 648
 649	new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
 650	ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
 651					    GLOBAL_BITMAP_SYSTEM_INODE,
 652					    OCFS2_INVALID_SLOT,
 653					    &goal_bit, &gd_bh);
 654	if (ret) {
 655		mlog_errno(ret);
 656		goto out_commit;
 657	}
 658
 659	/*
 660	 * probe the victim cluster group to find a proper
 661	 * region to fit wanted movement, it even will perfrom
 662	 * a best-effort attempt by compromising to a threshold
 663	 * around the goal.
 664	 */
 665	ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
 666				new_phys_cpos);
 667	if (!*new_phys_cpos) {
 668		ret = -ENOSPC;
 669		goto out_commit;
 670	}
 671
 672	ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
 673				  *new_phys_cpos, ext_flags);
 674	if (ret) {
 675		mlog_errno(ret);
 676		goto out_commit;
 677	}
 678
 679	gd = (struct ocfs2_group_desc *)gd_bh->b_data;
 680	ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
 681					       le16_to_cpu(gd->bg_chain));
 682	if (ret) {
 683		mlog_errno(ret);
 684		goto out_commit;
 685	}
 686
 687	ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
 688					 goal_bit, len, 0, 0);
 689	if (ret) {
 690		ocfs2_rollback_alloc_dinode_counts(gb_inode, gb_bh, len,
 691					       le16_to_cpu(gd->bg_chain));
 692		mlog_errno(ret);
 693	}
 694
 695	/*
 696	 * Here we should write the new page out first if we are
 697	 * in write-back mode.
 698	 */
 699	ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
 700	if (ret)
 701		mlog_errno(ret);
 702
 703out_commit:
 704	ocfs2_commit_trans(osb, handle);
 705	brelse(gd_bh);
 706
 707out_unlock_tl_inode:
 708	inode_unlock(tl_inode);
 709
 710	ocfs2_inode_unlock(gb_inode, 1);
 711out_unlock_gb_mutex:
 712	inode_unlock(gb_inode);
 713	brelse(gb_bh);
 714	iput(gb_inode);
 715
 716out:
 717	if (context->meta_ac) {
 718		ocfs2_free_alloc_context(context->meta_ac);
 719		context->meta_ac = NULL;
 720	}
 721
 722	if (ref_tree)
 723		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
 724
 725	return ret;
 726}
 727
 728/*
 729 * Helper to calculate the defraging length in one run according to threshold.
 730 */
 731static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
 732					 u32 threshold, int *skip)
 733{
 734	if ((*alloc_size + *len_defraged) < threshold) {
 735		/*
 736		 * proceed defragmentation until we meet the thresh
 737		 */
 738		*len_defraged += *alloc_size;
 739	} else if (*len_defraged == 0) {
 740		/*
 741		 * XXX: skip a large extent.
 742		 */
 743		*skip = 1;
 744	} else {
 745		/*
 746		 * split this extent to coalesce with former pieces as
 747		 * to reach the threshold.
 748		 *
 749		 * we're done here with one cycle of defragmentation
 750		 * in a size of 'thresh', resetting 'len_defraged'
 751		 * forces a new defragmentation.
 752		 */
 753		*alloc_size = threshold - *len_defraged;
 754		*len_defraged = 0;
 755	}
 756}
 757
 758static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
 759				struct ocfs2_move_extents_context *context)
 760{
 761	int ret = 0, flags, do_defrag, skip = 0;
 762	u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
 763	u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
 764
 765	struct inode *inode = context->inode;
 766	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 767	struct ocfs2_move_extents *range = context->range;
 768	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 769
 770	if ((i_size_read(inode) == 0) || (range->me_len == 0))
 771		return 0;
 772
 773	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 774		return 0;
 775
 776	context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
 777
 778	ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
 779	ocfs2_init_dealloc_ctxt(&context->dealloc);
 780
 781	/*
 782	 * TO-DO XXX:
 783	 *
 784	 * - xattr extents.
 785	 */
 786
 787	do_defrag = context->auto_defrag;
 788
 789	/*
 790	 * extents moving happens in unit of clusters, for the sake
 791	 * of simplicity, we may ignore two clusters where 'byte_start'
 792	 * and 'byte_start + len' were within.
 793	 */
 794	move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
 795	len_to_move = (range->me_start + range->me_len) >>
 796						osb->s_clustersize_bits;
 797	if (len_to_move >= move_start)
 798		len_to_move -= move_start;
 799	else
 800		len_to_move = 0;
 801
 802	if (do_defrag) {
 803		defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
 804		if (defrag_thresh <= 1)
 805			goto done;
 806	} else
 807		new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
 808							 range->me_goal);
 809
 810	mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
 811	     "thresh: %u\n",
 812	     (unsigned long long)OCFS2_I(inode)->ip_blkno,
 813	     (unsigned long long)range->me_start,
 814	     (unsigned long long)range->me_len,
 815	     move_start, len_to_move, defrag_thresh);
 816
 817	cpos = move_start;
 818	while (len_to_move) {
 819		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
 820					 &flags);
 821		if (ret) {
 822			mlog_errno(ret);
 823			goto out;
 824		}
 825
 826		if (alloc_size > len_to_move)
 827			alloc_size = len_to_move;
 828
 829		/*
 830		 * XXX: how to deal with a hole:
 831		 *
 832		 * - skip the hole of course
 833		 * - force a new defragmentation
 834		 */
 835		if (!phys_cpos) {
 836			if (do_defrag)
 837				len_defraged = 0;
 838
 839			goto next;
 840		}
 841
 842		if (do_defrag) {
 843			ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
 844						     defrag_thresh, &skip);
 845			/*
 846			 * skip large extents
 847			 */
 848			if (skip) {
 849				skip = 0;
 850				goto next;
 851			}
 852
 853			mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
 854			     "alloc_size: %u, len_defraged: %u\n",
 855			     cpos, phys_cpos, alloc_size, len_defraged);
 856
 857			ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
 858						  &alloc_size, flags);
 859		} else {
 860			ret = ocfs2_move_extent(context, cpos, phys_cpos,
 861						&new_phys_cpos, alloc_size,
 862						flags);
 863
 864			new_phys_cpos += alloc_size;
 865		}
 866
 867		if (ret < 0) {
 868			mlog_errno(ret);
 869			goto out;
 870		}
 871
 872		context->clusters_moved += alloc_size;
 873next:
 874		cpos += alloc_size;
 875		len_to_move -= alloc_size;
 876	}
 877
 878done:
 879	range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
 880
 881out:
 882	range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
 883						      context->clusters_moved);
 884	range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
 885						       context->new_phys_cpos);
 886
 887	ocfs2_schedule_truncate_log_flush(osb, 1);
 888	ocfs2_run_deallocs(osb, &context->dealloc);
 889
 890	return ret;
 891}
 892
 893static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
 894{
 895	int status;
 896	handle_t *handle;
 897	struct inode *inode = context->inode;
 898	struct ocfs2_dinode *di;
 899	struct buffer_head *di_bh = NULL;
 900	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 901
 902	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
 903		return -EROFS;
 904
 905	inode_lock(inode);
 906
 907	/*
 908	 * This prevents concurrent writes from other nodes
 909	 */
 910	status = ocfs2_rw_lock(inode, 1);
 911	if (status) {
 912		mlog_errno(status);
 913		goto out;
 914	}
 915
 916	status = ocfs2_inode_lock(inode, &di_bh, 1);
 917	if (status) {
 918		mlog_errno(status);
 919		goto out_rw_unlock;
 920	}
 921
 922	/*
 923	 * rememer ip_xattr_sem also needs to be held if necessary
 924	 */
 925	down_write(&OCFS2_I(inode)->ip_alloc_sem);
 926
 927	status = __ocfs2_move_extents_range(di_bh, context);
 928
 929	up_write(&OCFS2_I(inode)->ip_alloc_sem);
 930	if (status) {
 931		mlog_errno(status);
 932		goto out_inode_unlock;
 933	}
 934
 935	/*
 936	 * We update ctime for these changes
 937	 */
 938	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
 939	if (IS_ERR(handle)) {
 940		status = PTR_ERR(handle);
 941		mlog_errno(status);
 942		goto out_inode_unlock;
 943	}
 944
 945	status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
 946					 OCFS2_JOURNAL_ACCESS_WRITE);
 947	if (status) {
 948		mlog_errno(status);
 949		goto out_commit;
 950	}
 951
 952	di = (struct ocfs2_dinode *)di_bh->b_data;
 953	inode_set_ctime_current(inode);
 954	di->i_ctime = cpu_to_le64(inode_get_ctime_sec(inode));
 955	di->i_ctime_nsec = cpu_to_le32(inode_get_ctime_nsec(inode));
 956	ocfs2_update_inode_fsync_trans(handle, inode, 0);
 957
 958	ocfs2_journal_dirty(handle, di_bh);
 959
 960out_commit:
 961	ocfs2_commit_trans(osb, handle);
 962
 963out_inode_unlock:
 964	brelse(di_bh);
 965	ocfs2_inode_unlock(inode, 1);
 966out_rw_unlock:
 967	ocfs2_rw_unlock(inode, 1);
 968out:
 969	inode_unlock(inode);
 970
 971	return status;
 972}
 973
 974int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
 975{
 976	int status;
 977
 978	struct inode *inode = file_inode(filp);
 979	struct ocfs2_move_extents range;
 980	struct ocfs2_move_extents_context *context;
 981
 982	if (!argp)
 983		return -EINVAL;
 984
 985	status = mnt_want_write_file(filp);
 986	if (status)
 987		return status;
 988
 989	if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE)) {
 990		status = -EPERM;
 991		goto out_drop;
 992	}
 993
 994	if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
 995		status = -EPERM;
 996		goto out_drop;
 997	}
 998
 999	context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
1000	if (!context) {
1001		status = -ENOMEM;
1002		mlog_errno(status);
1003		goto out_drop;
1004	}
1005
1006	context->inode = inode;
1007	context->file = filp;
1008
1009	if (copy_from_user(&range, argp, sizeof(range))) {
1010		status = -EFAULT;
1011		goto out_free;
1012	}
1013
1014	if (range.me_start > i_size_read(inode)) {
1015		status = -EINVAL;
1016		goto out_free;
1017	}
1018
1019	if (range.me_start + range.me_len > i_size_read(inode))
1020			range.me_len = i_size_read(inode) - range.me_start;
1021
1022	context->range = &range;
1023
1024	/*
1025	 * ok, the default theshold for the defragmentation
1026	 * is 1M, since our maximum clustersize was 1M also.
1027	 * any thought?
1028	 */
1029	if (!range.me_threshold)
1030		range.me_threshold = 1024 * 1024;
1031
1032	if (range.me_threshold > i_size_read(inode))
1033		range.me_threshold = i_size_read(inode);
1034
1035	if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
1036		context->auto_defrag = 1;
 
 
 
 
 
 
 
 
 
 
1037
1038		if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
1039			context->partial = 1;
1040	} else {
1041		/*
1042		 * first best-effort attempt to validate and adjust the goal
1043		 * (physical address in block), while it can't guarantee later
1044		 * operation can succeed all the time since global_bitmap may
1045		 * change a bit over time.
1046		 */
1047
1048		status = ocfs2_validate_and_adjust_move_goal(inode, &range);
1049		if (status)
1050			goto out_copy;
1051	}
1052
1053	status = ocfs2_move_extents(context);
1054	if (status)
1055		mlog_errno(status);
1056out_copy:
1057	/*
1058	 * movement/defragmentation may end up being partially completed,
1059	 * that's the reason why we need to return userspace the finished
1060	 * length and new_offset even if failure happens somewhere.
1061	 */
1062	if (copy_to_user(argp, &range, sizeof(range)))
1063		status = -EFAULT;
1064
1065out_free:
1066	kfree(context);
1067out_drop:
1068	mnt_drop_write_file(filp);
1069
1070	return status;
1071}