Linux Audio

Check our new training course

Loading...
v3.15
 
   1/*
   2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   3 * Copyright (c) 2012 Red Hat, Inc.
   4 * All Rights Reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it would be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write the Free Software Foundation,
  17 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18 */
  19#include "xfs.h"
  20#include "xfs_fs.h"
  21#include "xfs_shared.h"
  22#include "xfs_format.h"
  23#include "xfs_log_format.h"
  24#include "xfs_trans_resv.h"
  25#include "xfs_bit.h"
  26#include "xfs_sb.h"
  27#include "xfs_ag.h"
  28#include "xfs_mount.h"
  29#include "xfs_da_format.h"
  30#include "xfs_inode.h"
  31#include "xfs_btree.h"
  32#include "xfs_trans.h"
  33#include "xfs_extfree_item.h"
  34#include "xfs_alloc.h"
  35#include "xfs_bmap.h"
  36#include "xfs_bmap_util.h"
  37#include "xfs_bmap_btree.h"
  38#include "xfs_rtalloc.h"
  39#include "xfs_error.h"
  40#include "xfs_quota.h"
  41#include "xfs_trans_space.h"
  42#include "xfs_trace.h"
  43#include "xfs_icache.h"
  44#include "xfs_log.h"
  45#include "xfs_dinode.h"
 
 
  46
  47/* Kernel only BMAP related definitions and functions */
  48
  49/*
  50 * Convert the given file system block to a disk block.  We have to treat it
  51 * differently based on whether the file is a real time file or not, because the
  52 * bmap code does.
  53 */
  54xfs_daddr_t
  55xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
  56{
  57	return (XFS_IS_REALTIME_INODE(ip) ? \
  58		 (xfs_daddr_t)XFS_FSB_TO_BB((ip)->i_mount, (fsb)) : \
  59		 XFS_FSB_TO_DADDR((ip)->i_mount, (fsb)));
  60}
  61
  62/*
  63 * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
  64 * caller.  Frees all the extents that need freeing, which must be done
  65 * last due to locking considerations.  We never free any extents in
  66 * the first transaction.
  67 *
  68 * Return 1 if the given transaction was committed and a new one
  69 * started, and 0 otherwise in the committed parameter.
  70 */
  71int						/* error */
  72xfs_bmap_finish(
  73	xfs_trans_t		**tp,		/* transaction pointer addr */
  74	xfs_bmap_free_t		*flist,		/* i/o: list extents to free */
  75	int			*committed)	/* xact committed or not */
  76{
  77	xfs_efd_log_item_t	*efd;		/* extent free data */
  78	xfs_efi_log_item_t	*efi;		/* extent free intention */
  79	int			error;		/* error return value */
  80	xfs_bmap_free_item_t	*free;		/* free extent item */
  81	struct xfs_trans_res	tres;		/* new log reservation */
  82	xfs_mount_t		*mp;		/* filesystem mount structure */
  83	xfs_bmap_free_item_t	*next;		/* next item on free list */
  84	xfs_trans_t		*ntp;		/* new transaction pointer */
  85
  86	ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES);
  87	if (flist->xbf_count == 0) {
  88		*committed = 0;
  89		return 0;
  90	}
  91	ntp = *tp;
  92	efi = xfs_trans_get_efi(ntp, flist->xbf_count);
  93	for (free = flist->xbf_first; free; free = free->xbfi_next)
  94		xfs_trans_log_efi_extent(ntp, efi, free->xbfi_startblock,
  95			free->xbfi_blockcount);
  96
  97	tres.tr_logres = ntp->t_log_res;
  98	tres.tr_logcount = ntp->t_log_count;
  99	tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
 100	ntp = xfs_trans_dup(*tp);
 101	error = xfs_trans_commit(*tp, 0);
 102	*tp = ntp;
 103	*committed = 1;
 104	/*
 105	 * We have a new transaction, so we should return committed=1,
 106	 * even though we're returning an error.
 107	 */
 108	if (error)
 109		return error;
 110
 111	/*
 112	 * transaction commit worked ok so we can drop the extra ticket
 113	 * reference that we gained in xfs_trans_dup()
 114	 */
 115	xfs_log_ticket_put(ntp->t_ticket);
 116
 117	error = xfs_trans_reserve(ntp, &tres, 0, 0);
 118	if (error)
 119		return error;
 120	efd = xfs_trans_get_efd(ntp, efi, flist->xbf_count);
 121	for (free = flist->xbf_first; free != NULL; free = next) {
 122		next = free->xbfi_next;
 123		if ((error = xfs_free_extent(ntp, free->xbfi_startblock,
 124				free->xbfi_blockcount))) {
 125			/*
 126			 * The bmap free list will be cleaned up at a
 127			 * higher level.  The EFI will be canceled when
 128			 * this transaction is aborted.
 129			 * Need to force shutdown here to make sure it
 130			 * happens, since this transaction may not be
 131			 * dirty yet.
 132			 */
 133			mp = ntp->t_mountp;
 134			if (!XFS_FORCED_SHUTDOWN(mp))
 135				xfs_force_shutdown(mp,
 136						   (error == EFSCORRUPTED) ?
 137						   SHUTDOWN_CORRUPT_INCORE :
 138						   SHUTDOWN_META_IO_ERROR);
 139			return error;
 140		}
 141		xfs_trans_log_efd_extent(ntp, efd, free->xbfi_startblock,
 142			free->xbfi_blockcount);
 143		xfs_bmap_del_free(flist, NULL, free);
 144	}
 145	return 0;
 146}
 147
 148int
 149xfs_bmap_rtalloc(
 150	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
 
 
 151{
 152	xfs_alloctype_t	atype = 0;	/* type for allocation routines */
 153	int		error;		/* error return value */
 154	xfs_mount_t	*mp;		/* mount point structure */
 155	xfs_extlen_t	prod = 0;	/* product factor for allocators */
 156	xfs_extlen_t	ralen = 0;	/* realtime allocation length */
 157	xfs_extlen_t	align;		/* minimum allocation alignment */
 158	xfs_rtblock_t	rtb;
 159
 160	mp = ap->ip->i_mount;
 161	align = xfs_get_extsz_hint(ap->ip);
 162	prod = align / mp->m_sb.sb_rextsize;
 163	error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
 164					align, 1, ap->eof, 0,
 165					ap->conv, &ap->offset, &ap->length);
 166	if (error)
 167		return error;
 168	ASSERT(ap->length);
 169	ASSERT(ap->length % mp->m_sb.sb_rextsize == 0);
 170
 171	/*
 172	 * If the offset & length are not perfectly aligned
 173	 * then kill prod, it will just get us in trouble.
 174	 */
 175	if (do_mod(ap->offset, align) || ap->length % align)
 176		prod = 1;
 177	/*
 178	 * Set ralen to be the actual requested length in rtextents.
 179	 */
 180	ralen = ap->length / mp->m_sb.sb_rextsize;
 181	/*
 182	 * If the old value was close enough to MAXEXTLEN that
 183	 * we rounded up to it, cut it back so it's valid again.
 184	 * Note that if it's a really large request (bigger than
 185	 * MAXEXTLEN), we don't hear about that number, and can't
 186	 * adjust the starting point to match it.
 187	 */
 188	if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN)
 189		ralen = MAXEXTLEN / mp->m_sb.sb_rextsize;
 190
 191	/*
 192	 * Lock out other modifications to the RT bitmap inode.
 193	 */
 194	xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
 195	xfs_trans_ijoin(ap->tp, mp->m_rbmip, XFS_ILOCK_EXCL);
 196
 197	/*
 198	 * If it's an allocation to an empty file at offset 0,
 199	 * pick an extent that will space things out in the rt area.
 200	 */
 201	if (ap->eof && ap->offset == 0) {
 202		xfs_rtblock_t uninitialized_var(rtx); /* realtime extent no */
 203
 204		error = xfs_rtpick_extent(mp, ap->tp, ralen, &rtx);
 205		if (error)
 206			return error;
 207		ap->blkno = rtx * mp->m_sb.sb_rextsize;
 208	} else {
 209		ap->blkno = 0;
 210	}
 211
 212	xfs_bmap_adjacent(ap);
 213
 214	/*
 215	 * Realtime allocation, done through xfs_rtallocate_extent.
 216	 */
 217	atype = ap->blkno == 0 ?  XFS_ALLOCTYPE_ANY_AG : XFS_ALLOCTYPE_NEAR_BNO;
 218	do_div(ap->blkno, mp->m_sb.sb_rextsize);
 219	rtb = ap->blkno;
 220	ap->length = ralen;
 221	if ((error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1, ap->length,
 222				&ralen, atype, ap->wasdel, prod, &rtb)))
 223		return error;
 224	if (rtb == NULLFSBLOCK && prod > 1 &&
 225	    (error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1,
 226					   ap->length, &ralen, atype,
 227					   ap->wasdel, 1, &rtb)))
 228		return error;
 229	ap->blkno = rtb;
 230	if (ap->blkno != NULLFSBLOCK) {
 231		ap->blkno *= mp->m_sb.sb_rextsize;
 232		ralen *= mp->m_sb.sb_rextsize;
 233		ap->length = ralen;
 234		ap->ip->i_d.di_nblocks += ralen;
 235		xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
 236		if (ap->wasdel)
 237			ap->ip->i_delayed_blks -= ralen;
 238		/*
 239		 * Adjust the disk quota also. This was reserved
 240		 * earlier.
 241		 */
 242		xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
 243			ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT :
 244					XFS_TRANS_DQ_RTBCOUNT, (long) ralen);
 245	} else {
 246		ap->length = 0;
 247	}
 248	return 0;
 249}
 250
 251/*
 252 * Stack switching interfaces for allocation
 253 */
 254static void
 255xfs_bmapi_allocate_worker(
 256	struct work_struct	*work)
 257{
 258	struct xfs_bmalloca	*args = container_of(work,
 259						struct xfs_bmalloca, work);
 260	unsigned long		pflags;
 261
 262	/* we are in a transaction context here */
 263	current_set_flags_nested(&pflags, PF_FSTRANS);
 264
 265	args->result = __xfs_bmapi_allocate(args);
 266	complete(args->done);
 267
 268	current_restore_flags_nested(&pflags, PF_FSTRANS);
 269}
 270
 271/*
 272 * Some allocation requests often come in with little stack to work on. Push
 273 * them off to a worker thread so there is lots of stack to use. Otherwise just
 274 * call directly to avoid the context switch overhead here.
 275 */
 276int
 277xfs_bmapi_allocate(
 278	struct xfs_bmalloca	*args)
 
 279{
 280	DECLARE_COMPLETION_ONSTACK(done);
 281
 282	if (!args->stack_switch)
 283		return __xfs_bmapi_allocate(args);
 284
 
 
 
 
 
 
 285
 286	args->done = &done;
 287	INIT_WORK_ONSTACK(&args->work, xfs_bmapi_allocate_worker);
 288	queue_work(xfs_alloc_wq, &args->work);
 289	wait_for_completion(&done);
 290	destroy_work_on_stack(&args->work);
 291	return args->result;
 292}
 293
 294/*
 295 * Check if the endoff is outside the last extent. If so the caller will grow
 296 * the allocation to a stripe unit boundary.  All offsets are considered outside
 297 * the end of file for an empty fork, so 1 is returned in *eof in that case.
 298 */
 299int
 300xfs_bmap_eof(
 
 301	struct xfs_inode	*ip,
 302	xfs_fileoff_t		endoff,
 303	int			whichfork,
 304	int			*eof)
 
 305{
 306	struct xfs_bmbt_irec	rec;
 
 
 
 307	int			error;
 308
 309	error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, eof);
 310	if (error || *eof)
 311		return error;
 312
 313	*eof = endoff >= rec.br_startoff + rec.br_blockcount;
 314	return 0;
 315}
 316
 317/*
 318 * Extent tree block counting routines.
 319 */
 
 
 320
 321/*
 322 * Count leaf blocks given a range of extent records.
 323 */
 324STATIC void
 325xfs_bmap_count_leaves(
 326	xfs_ifork_t		*ifp,
 327	xfs_extnum_t		idx,
 328	int			numrecs,
 329	int			*count)
 330{
 331	int		b;
 332
 333	for (b = 0; b < numrecs; b++) {
 334		xfs_bmbt_rec_host_t *frp = xfs_iext_get_ext(ifp, idx + b);
 335		*count += xfs_bmbt_get_blockcount(frp);
 336	}
 337}
 338
 339/*
 340 * Count leaf blocks given a range of extent records originally
 341 * in btree format.
 342 */
 343STATIC void
 344xfs_bmap_disk_count_leaves(
 345	struct xfs_mount	*mp,
 346	struct xfs_btree_block	*block,
 347	int			numrecs,
 348	int			*count)
 349{
 350	int		b;
 351	xfs_bmbt_rec_t	*frp;
 352
 353	for (b = 1; b <= numrecs; b++) {
 354		frp = XFS_BMBT_REC_ADDR(mp, block, b);
 355		*count += xfs_bmbt_disk_get_blockcount(frp);
 356	}
 
 
 357}
 358
 359/*
 360 * Recursively walks each level of a btree
 361 * to count total fsblocks in use.
 362 */
 363STATIC int                                     /* error */
 364xfs_bmap_count_tree(
 365	xfs_mount_t     *mp,            /* file system mount point */
 366	xfs_trans_t     *tp,            /* transaction pointer */
 367	xfs_ifork_t	*ifp,		/* inode fork pointer */
 368	xfs_fsblock_t   blockno,	/* file system block number */
 369	int             levelin,	/* level in btree */
 370	int		*count)		/* Count of blocks */
 371{
 
 
 372	int			error;
 373	xfs_buf_t		*bp, *nbp;
 374	int			level = levelin;
 375	__be64			*pp;
 376	xfs_fsblock_t           bno = blockno;
 377	xfs_fsblock_t		nextbno;
 378	struct xfs_btree_block	*block, *nextblock;
 379	int			numrecs;
 380
 381	error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp, XFS_BMAP_BTREE_REF,
 382						&xfs_bmbt_buf_ops);
 383	if (error)
 384		return error;
 385	*count += 1;
 386	block = XFS_BUF_TO_BLOCK(bp);
 387
 388	if (--level) {
 389		/* Not at node above leaves, count this level of nodes */
 390		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 391		while (nextbno != NULLFSBLOCK) {
 392			error = xfs_btree_read_bufl(mp, tp, nextbno, 0, &nbp,
 393						XFS_BMAP_BTREE_REF,
 394						&xfs_bmbt_buf_ops);
 395			if (error)
 396				return error;
 397			*count += 1;
 398			nextblock = XFS_BUF_TO_BLOCK(nbp);
 399			nextbno = be64_to_cpu(nextblock->bb_u.l.bb_rightsib);
 400			xfs_trans_brelse(tp, nbp);
 401		}
 402
 403		/* Dive to the next level */
 404		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
 405		bno = be64_to_cpu(*pp);
 406		if (unlikely((error =
 407		     xfs_bmap_count_tree(mp, tp, ifp, bno, level, count)) < 0)) {
 408			xfs_trans_brelse(tp, bp);
 409			XFS_ERROR_REPORT("xfs_bmap_count_tree(1)",
 410					 XFS_ERRLEVEL_LOW, mp);
 411			return XFS_ERROR(EFSCORRUPTED);
 412		}
 413		xfs_trans_brelse(tp, bp);
 414	} else {
 415		/* count all level 1 nodes and their leaves */
 416		for (;;) {
 417			nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 418			numrecs = be16_to_cpu(block->bb_numrecs);
 419			xfs_bmap_disk_count_leaves(mp, block, numrecs, count);
 420			xfs_trans_brelse(tp, bp);
 421			if (nextbno == NULLFSBLOCK)
 422				break;
 423			bno = nextbno;
 424			error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
 425						XFS_BMAP_BTREE_REF,
 426						&xfs_bmbt_buf_ops);
 427			if (error)
 428				return error;
 429			*count += 1;
 430			block = XFS_BUF_TO_BLOCK(bp);
 431		}
 432	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 433	return 0;
 434}
 435
 436/*
 437 * Count fsblocks of the given fork.
 438 */
 439int						/* error */
 440xfs_bmap_count_blocks(
 441	xfs_trans_t		*tp,		/* transaction pointer */
 442	xfs_inode_t		*ip,		/* incore inode */
 443	int			whichfork,	/* data or attr fork */
 444	int			*count)		/* out: count of blocks */
 445{
 446	struct xfs_btree_block	*block;	/* current btree block */
 447	xfs_fsblock_t		bno;	/* block # of "block" */
 448	xfs_ifork_t		*ifp;	/* fork structure */
 449	int			level;	/* btree level, for checking */
 450	xfs_mount_t		*mp;	/* file system mount structure */
 451	__be64			*pp;	/* pointer to block address */
 452
 453	bno = NULLFSBLOCK;
 454	mp = ip->i_mount;
 455	ifp = XFS_IFORK_PTR(ip, whichfork);
 456	if ( XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ) {
 457		xfs_bmap_count_leaves(ifp, 0,
 458			ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t),
 459			count);
 460		return 0;
 461	}
 462
 463	/*
 464	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
 465	 */
 466	block = ifp->if_broot;
 467	level = be16_to_cpu(block->bb_level);
 468	ASSERT(level > 0);
 469	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
 470	bno = be64_to_cpu(*pp);
 471	ASSERT(bno != NULLDFSBNO);
 472	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
 473	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
 474
 475	if (unlikely(xfs_bmap_count_tree(mp, tp, ifp, bno, level, count) < 0)) {
 476		XFS_ERROR_REPORT("xfs_bmap_count_blocks(2)", XFS_ERRLEVEL_LOW,
 477				 mp);
 478		return XFS_ERROR(EFSCORRUPTED);
 479	}
 480
 481	return 0;
 
 
 
 
 
 
 482}
 483
 484/*
 485 * returns 1 for success, 0 if we failed to map the extent.
 486 */
 487STATIC int
 488xfs_getbmapx_fix_eof_hole(
 489	xfs_inode_t		*ip,		/* xfs incore inode pointer */
 490	struct getbmapx		*out,		/* output structure */
 491	int			prealloced,	/* this is a file with
 492						 * preallocated data space */
 493	__int64_t		end,		/* last block requested */
 494	xfs_fsblock_t		startblock)
 495{
 496	__int64_t		fixlen;
 497	xfs_mount_t		*mp;		/* file system mount point */
 498	xfs_ifork_t		*ifp;		/* inode fork pointer */
 499	xfs_extnum_t		lastx;		/* last extent pointer */
 500	xfs_fileoff_t		fileblock;
 501
 502	if (startblock == HOLESTARTBLOCK) {
 503		mp = ip->i_mount;
 504		out->bmv_block = -1;
 505		fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, XFS_ISIZE(ip)));
 506		fixlen -= out->bmv_offset;
 507		if (prealloced && out->bmv_offset + out->bmv_length == end) {
 508			/* Came to hole at EOF. Trim it. */
 509			if (fixlen <= 0)
 510				return 0;
 511			out->bmv_length = fixlen;
 512		}
 513	} else {
 514		if (startblock == DELAYSTARTBLOCK)
 515			out->bmv_block = -2;
 516		else
 517			out->bmv_block = xfs_fsb_to_db(ip, startblock);
 518		fileblock = XFS_BB_TO_FSB(ip->i_mount, out->bmv_offset);
 519		ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
 520		if (xfs_iext_bno_to_ext(ifp, fileblock, &lastx) &&
 521		   (lastx == (ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t))-1))
 522			out->bmv_oflags |= BMV_OF_LAST;
 523	}
 524
 525	return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 526}
 527
 528/*
 529 * Get inode's extents as described in bmv, and format for output.
 530 * Calls formatter to fill the user's buffer until all extents
 531 * are mapped, until the passed-in bmv->bmv_count slots have
 532 * been filled, or until the formatter short-circuits the loop,
 533 * if it is tracking filled-in extents on its own.
 534 */
 535int						/* error code */
 536xfs_getbmap(
 537	xfs_inode_t		*ip,
 538	struct getbmapx		*bmv,		/* user bmap structure */
 539	xfs_bmap_format_t	formatter,	/* format to user */
 540	void			*arg)		/* formatter arg */
 541{
 542	__int64_t		bmvend;		/* last block requested */
 543	int			error = 0;	/* return value */
 544	__int64_t		fixlen;		/* length for -1 case */
 545	int			i;		/* extent number */
 546	int			lock;		/* lock state */
 547	xfs_bmbt_irec_t		*map;		/* buffer for user's data */
 548	xfs_mount_t		*mp;		/* file system mount point */
 549	int			nex;		/* # of user extents can do */
 550	int			nexleft;	/* # of user extents left */
 551	int			subnex;		/* # of bmapi's can do */
 552	int			nmap;		/* number of map entries */
 553	struct getbmapx		*out;		/* output structure */
 554	int			whichfork;	/* data or attr fork */
 555	int			prealloced;	/* this is a file with
 556						 * preallocated data space */
 557	int			iflags;		/* interface flags */
 558	int			bmapi_flags;	/* flags for xfs_bmapi */
 559	int			cur_ext = 0;
 560
 561	mp = ip->i_mount;
 562	iflags = bmv->bmv_iflags;
 563	whichfork = iflags & BMV_IF_ATTRFORK ? XFS_ATTR_FORK : XFS_DATA_FORK;
 564
 565	if (whichfork == XFS_ATTR_FORK) {
 566		if (XFS_IFORK_Q(ip)) {
 567			if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS &&
 568			    ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE &&
 569			    ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)
 570				return XFS_ERROR(EINVAL);
 571		} else if (unlikely(
 572			   ip->i_d.di_aformat != 0 &&
 573			   ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS)) {
 574			XFS_ERROR_REPORT("xfs_getbmap", XFS_ERRLEVEL_LOW,
 575					 ip->i_mount);
 576			return XFS_ERROR(EFSCORRUPTED);
 577		}
 578
 579		prealloced = 0;
 580		fixlen = 1LL << 32;
 581	} else {
 582		if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS &&
 583		    ip->i_d.di_format != XFS_DINODE_FMT_BTREE &&
 584		    ip->i_d.di_format != XFS_DINODE_FMT_LOCAL)
 585			return XFS_ERROR(EINVAL);
 586
 587		if (xfs_get_extsz_hint(ip) ||
 588		    ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC|XFS_DIFLAG_APPEND)){
 589			prealloced = 1;
 590			fixlen = mp->m_super->s_maxbytes;
 591		} else {
 592			prealloced = 0;
 593			fixlen = XFS_ISIZE(ip);
 594		}
 595	}
 596
 597	if (bmv->bmv_length == -1) {
 598		fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, fixlen));
 599		bmv->bmv_length =
 600			max_t(__int64_t, fixlen - bmv->bmv_offset, 0);
 601	} else if (bmv->bmv_length == 0) {
 602		bmv->bmv_entries = 0;
 603		return 0;
 604	} else if (bmv->bmv_length < 0) {
 605		return XFS_ERROR(EINVAL);
 606	}
 607
 608	nex = bmv->bmv_count - 1;
 609	if (nex <= 0)
 610		return XFS_ERROR(EINVAL);
 611	bmvend = bmv->bmv_offset + bmv->bmv_length;
 
 
 612
 
 
 
 
 
 
 613
 614	if (bmv->bmv_count > ULONG_MAX / sizeof(struct getbmapx))
 615		return XFS_ERROR(ENOMEM);
 616	out = kmem_zalloc_large(bmv->bmv_count * sizeof(struct getbmapx), 0);
 617	if (!out)
 618		return XFS_ERROR(ENOMEM);
 
 
 
 
 619
 620	xfs_ilock(ip, XFS_IOLOCK_SHARED);
 621	if (whichfork == XFS_DATA_FORK) {
 
 
 
 
 622		if (!(iflags & BMV_IF_DELALLOC) &&
 623		    (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size)) {
 624			error = -filemap_write_and_wait(VFS_I(ip)->i_mapping);
 625			if (error)
 626				goto out_unlock_iolock;
 627
 628			/*
 629			 * Even after flushing the inode, there can still be
 630			 * delalloc blocks on the inode beyond EOF due to
 631			 * speculative preallocation.  These are not removed
 632			 * until the release function is called or the inode
 633			 * is inactivated.  Hence we cannot assert here that
 634			 * ip->i_delayed_blks == 0.
 635			 */
 636		}
 637
 
 
 
 
 
 
 638		lock = xfs_ilock_data_map_shared(ip);
 639	} else {
 640		lock = xfs_ilock_attr_map_shared(ip);
 641	}
 642
 643	/*
 644	 * Don't let nex be bigger than the number of extents
 645	 * we can have assuming alternating holes and real extents.
 646	 */
 647	if (nex > XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1)
 648		nex = XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1;
 649
 650	bmapi_flags = xfs_bmapi_aflag(whichfork);
 651	if (!(iflags & BMV_IF_PREALLOC))
 652		bmapi_flags |= XFS_BMAPI_IGSTATE;
 653
 654	/*
 655	 * Allocate enough space to handle "subnex" maps at a time.
 656	 */
 657	error = ENOMEM;
 658	subnex = 16;
 659	map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS);
 660	if (!map)
 
 
 661		goto out_unlock_ilock;
 662
 663	bmv->bmv_entries = 0;
 664
 665	if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0 &&
 666	    (whichfork == XFS_ATTR_FORK || !(iflags & BMV_IF_DELALLOC))) {
 667		error = 0;
 668		goto out_free_map;
 669	}
 670
 671	nexleft = nex;
 
 
 
 672
 673	do {
 674		nmap = (nexleft > subnex) ? subnex : nexleft;
 675		error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset),
 676				       XFS_BB_TO_FSB(mp, bmv->bmv_length),
 677				       map, &nmap, bmapi_flags);
 678		if (error)
 679			goto out_free_map;
 680		ASSERT(nmap <= subnex);
 681
 682		for (i = 0; i < nmap && nexleft && bmv->bmv_length; i++) {
 683			out[cur_ext].bmv_oflags = 0;
 684			if (map[i].br_state == XFS_EXT_UNWRITTEN)
 685				out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC;
 686			else if (map[i].br_startblock == DELAYSTARTBLOCK)
 687				out[cur_ext].bmv_oflags |= BMV_OF_DELALLOC;
 688			out[cur_ext].bmv_offset =
 689				XFS_FSB_TO_BB(mp, map[i].br_startoff);
 690			out[cur_ext].bmv_length =
 691				XFS_FSB_TO_BB(mp, map[i].br_blockcount);
 692			out[cur_ext].bmv_unused1 = 0;
 693			out[cur_ext].bmv_unused2 = 0;
 694
 695			/*
 696			 * delayed allocation extents that start beyond EOF can
 697			 * occur due to speculative EOF allocation when the
 698			 * delalloc extent is larger than the largest freespace
 699			 * extent at conversion time. These extents cannot be
 700			 * converted by data writeback, so can exist here even
 701			 * if we are not supposed to be finding delalloc
 702			 * extents.
 703			 */
 704			if (map[i].br_startblock == DELAYSTARTBLOCK &&
 705			    map[i].br_startoff <= XFS_B_TO_FSB(mp, XFS_ISIZE(ip)))
 706				ASSERT((iflags & BMV_IF_DELALLOC) != 0);
 707
 708                        if (map[i].br_startblock == HOLESTARTBLOCK &&
 709			    whichfork == XFS_ATTR_FORK) {
 710				/* came to the end of attribute fork */
 711				out[cur_ext].bmv_oflags |= BMV_OF_LAST;
 712				goto out_free_map;
 713			}
 714
 715			if (!xfs_getbmapx_fix_eof_hole(ip, &out[cur_ext],
 716					prealloced, bmvend,
 717					map[i].br_startblock))
 718				goto out_free_map;
 719
 720			bmv->bmv_offset =
 721				out[cur_ext].bmv_offset +
 722				out[cur_ext].bmv_length;
 723			bmv->bmv_length =
 724				max_t(__int64_t, 0, bmvend - bmv->bmv_offset);
 725
 726			/*
 727			 * In case we don't want to return the hole,
 728			 * don't increase cur_ext so that we can reuse
 729			 * it in the next loop.
 730			 */
 731			if ((iflags & BMV_IF_NO_HOLES) &&
 732			    map[i].br_startblock == HOLESTARTBLOCK) {
 733				memset(&out[cur_ext], 0, sizeof(out[cur_ext]));
 734				continue;
 735			}
 736
 737			nexleft--;
 738			bmv->bmv_entries++;
 739			cur_ext++;
 
 
 
 
 
 
 740		}
 741	} while (nmap && nexleft && bmv->bmv_length);
 742
 743 out_free_map:
 744	kmem_free(map);
 745 out_unlock_ilock:
 746	xfs_iunlock(ip, lock);
 747 out_unlock_iolock:
 748	xfs_iunlock(ip, XFS_IOLOCK_SHARED);
 749
 750	for (i = 0; i < cur_ext; i++) {
 751		int full = 0;	/* user array is full */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 752
 753		/* format results & advance arg */
 754		error = formatter(&arg, &out[i], &full);
 755		if (error || full)
 756			break;
 757	}
 758
 759	kmem_free(out);
 
 
 
 760	return error;
 761}
 762
 763/*
 764 * dead simple method of punching delalyed allocation blocks from a range in
 765 * the inode. Walks a block at a time so will be slow, but is only executed in
 766 * rare error cases so the overhead is not critical. This will always punch out
 767 * both the start and end blocks, even if the ranges only partially overlap
 768 * them, so it is up to the caller to ensure that partial blocks are not
 769 * passed in.
 770 */
 771int
 772xfs_bmap_punch_delalloc_range(
 773	struct xfs_inode	*ip,
 774	xfs_fileoff_t		start_fsb,
 775	xfs_fileoff_t		length)
 
 776{
 777	xfs_fileoff_t		remaining = length;
 778	int			error = 0;
 
 
 
 
 779
 780	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 781
 782	do {
 783		int		done;
 784		xfs_bmbt_irec_t	imap;
 785		int		nimaps = 1;
 786		xfs_fsblock_t	firstblock;
 787		xfs_bmap_free_t flist;
 788
 789		/*
 790		 * Map the range first and check that it is a delalloc extent
 791		 * before trying to unmap the range. Otherwise we will be
 792		 * trying to remove a real extent (which requires a
 793		 * transaction) or a hole, which is probably a bad idea...
 794		 */
 795		error = xfs_bmapi_read(ip, start_fsb, 1, &imap, &nimaps,
 796				       XFS_BMAPI_ENTIRE);
 797
 798		if (error) {
 799			/* something screwed, just bail */
 800			if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
 801				xfs_alert(ip->i_mount,
 802			"Failed delalloc mapping lookup ino %lld fsb %lld.",
 803						ip->i_ino, start_fsb);
 804			}
 805			break;
 806		}
 807		if (!nimaps) {
 808			/* nothing there */
 809			goto next_block;
 810		}
 811		if (imap.br_startblock != DELAYSTARTBLOCK) {
 812			/* been converted, ignore */
 813			goto next_block;
 814		}
 815		WARN_ON(imap.br_blockcount == 0);
 816
 817		/*
 818		 * Note: while we initialise the firstblock/flist pair, they
 819		 * should never be used because blocks should never be
 820		 * allocated or freed for a delalloc extent and hence we need
 821		 * don't cancel or finish them after the xfs_bunmapi() call.
 822		 */
 823		xfs_bmap_init(&flist, &firstblock);
 824		error = xfs_bunmapi(NULL, ip, start_fsb, 1, 0, 1, &firstblock,
 825					&flist, &done);
 826		if (error)
 827			break;
 
 828
 829		ASSERT(!flist.xbf_count && !flist.xbf_first);
 830next_block:
 831		start_fsb++;
 832		remaining--;
 833	} while(remaining > 0);
 834
 835	return error;
 
 836}
 837
 838/*
 839 * Test whether it is appropriate to check an inode for and free post EOF
 840 * blocks. The 'force' parameter determines whether we should also consider
 841 * regular files that are marked preallocated or append-only.
 842 */
 843bool
 844xfs_can_free_eofblocks(struct xfs_inode *ip, bool force)
 
 845{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 846	/* prealloc/delalloc exists only on regular files */
 847	if (!S_ISREG(ip->i_d.di_mode))
 848		return false;
 849
 850	/*
 851	 * Zero sized files with no cached pages and delalloc blocks will not
 852	 * have speculative prealloc/delalloc blocks to remove.
 853	 */
 854	if (VFS_I(ip)->i_size == 0 &&
 855	    VN_CACHED(VFS_I(ip)) == 0 &&
 856	    ip->i_delayed_blks == 0)
 857		return false;
 858
 859	/* If we haven't read in the extent list, then don't do it now. */
 860	if (!(ip->i_df.if_flags & XFS_IFEXTENTS))
 861		return false;
 862
 863	/*
 864	 * Do not free real preallocated or append-only files unless the file
 865	 * has delalloc blocks and we are forced to remove them.
 866	 */
 867	if (ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))
 868		if (!force || ip->i_delayed_blks == 0)
 869			return false;
 870
 871	return true;
 872}
 873
 874/*
 875 * This is called by xfs_inactive to free any blocks beyond eof
 876 * when the link count isn't zero and by xfs_dm_punch_hole() when
 877 * punching a hole to EOF.
 878 */
 879int
 880xfs_free_eofblocks(
 881	xfs_mount_t	*mp,
 882	xfs_inode_t	*ip,
 883	bool		need_iolock)
 884{
 885	xfs_trans_t	*tp;
 886	int		error;
 887	xfs_fileoff_t	end_fsb;
 888	xfs_fileoff_t	last_fsb;
 889	xfs_filblks_t	map_len;
 890	int		nimaps;
 891	xfs_bmbt_irec_t	imap;
 892
 893	/*
 894	 * Figure out if there are any blocks beyond the end
 895	 * of the file.  If not, then there is nothing to do.
 
 896	 */
 897	end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip));
 
 
 898	last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
 899	if (last_fsb <= end_fsb)
 900		return 0;
 901	map_len = last_fsb - end_fsb;
 902
 903	nimaps = 1;
 
 
 
 
 
 904	xfs_ilock(ip, XFS_ILOCK_SHARED);
 905	error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0);
 
 
 906	xfs_iunlock(ip, XFS_ILOCK_SHARED);
 
 
 907
 908	if (!error && (nimaps != 0) &&
 909	    (imap.br_startblock != HOLESTARTBLOCK ||
 910	     ip->i_delayed_blks)) {
 911		/*
 912		 * Attach the dquots to the inode up front.
 913		 */
 914		error = xfs_qm_dqattach(ip, 0);
 915		if (error)
 916			return error;
 
 
 
 917
 918		/*
 919		 * There are blocks after the end of file.
 920		 * Free them up now by truncating the file to
 921		 * its current size.
 922		 */
 923		tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
 924
 925		if (need_iolock) {
 926			if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
 927				xfs_trans_cancel(tp, 0);
 928				return EAGAIN;
 929			}
 930		}
 931
 932		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
 933		if (error) {
 934			ASSERT(XFS_FORCED_SHUTDOWN(mp));
 935			xfs_trans_cancel(tp, 0);
 936			if (need_iolock)
 937				xfs_iunlock(ip, XFS_IOLOCK_EXCL);
 938			return error;
 
 
 
 
 939		}
 
 
 
 940
 941		xfs_ilock(ip, XFS_ILOCK_EXCL);
 942		xfs_trans_ijoin(tp, ip, 0);
 
 
 
 943
 944		/*
 945		 * Do not update the on-disk file size.  If we update the
 946		 * on-disk file size and then the system crashes before the
 947		 * contents of the file are flushed to disk then the files
 948		 * may be full of holes (ie NULL files bug).
 949		 */
 950		error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK,
 951					      XFS_ISIZE(ip));
 952		if (error) {
 953			/*
 954			 * If we get an error at this point we simply don't
 955			 * bother truncating the file.
 956			 */
 957			xfs_trans_cancel(tp,
 958					 (XFS_TRANS_RELEASE_LOG_RES |
 959					  XFS_TRANS_ABORT));
 960		} else {
 961			error = xfs_trans_commit(tp,
 962						XFS_TRANS_RELEASE_LOG_RES);
 963			if (!error)
 964				xfs_inode_clear_eofblocks_tag(ip);
 965		}
 966
 967		xfs_iunlock(ip, XFS_ILOCK_EXCL);
 968		if (need_iolock)
 969			xfs_iunlock(ip, XFS_IOLOCK_EXCL);
 970	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 971	return error;
 972}
 973
 974int
 975xfs_alloc_file_space(
 976	struct xfs_inode	*ip,
 977	xfs_off_t		offset,
 978	xfs_off_t		len,
 979	int			alloc_type)
 980{
 981	xfs_mount_t		*mp = ip->i_mount;
 982	xfs_off_t		count;
 983	xfs_filblks_t		allocated_fsb;
 984	xfs_filblks_t		allocatesize_fsb;
 985	xfs_extlen_t		extsz, temp;
 986	xfs_fileoff_t		startoffset_fsb;
 987	xfs_fsblock_t		firstfsb;
 988	int			nimaps;
 989	int			quota_flag;
 990	int			rt;
 991	xfs_trans_t		*tp;
 992	xfs_bmbt_irec_t		imaps[1], *imapp;
 993	xfs_bmap_free_t		free_list;
 994	uint			qblocks, resblks, resrtextents;
 995	int			committed;
 996	int			error;
 997
 
 
 
 998	trace_xfs_alloc_file_space(ip);
 999
1000	if (XFS_FORCED_SHUTDOWN(mp))
1001		return XFS_ERROR(EIO);
1002
1003	error = xfs_qm_dqattach(ip, 0);
1004	if (error)
1005		return error;
1006
1007	if (len <= 0)
1008		return XFS_ERROR(EINVAL);
1009
1010	rt = XFS_IS_REALTIME_INODE(ip);
1011	extsz = xfs_get_extsz_hint(ip);
1012
1013	count = len;
1014	imapp = &imaps[0];
1015	nimaps = 1;
1016	startoffset_fsb	= XFS_B_TO_FSBT(mp, offset);
1017	allocatesize_fsb = XFS_B_TO_FSB(mp, count);
 
1018
1019	/*
1020	 * Allocate file space until done or until there is an error
1021	 */
1022	while (allocatesize_fsb && !error) {
1023		xfs_fileoff_t	s, e;
 
 
1024
1025		/*
1026		 * Determine space reservations for data/realtime.
1027		 */
1028		if (unlikely(extsz)) {
1029			s = startoffset_fsb;
1030			do_div(s, extsz);
1031			s *= extsz;
1032			e = startoffset_fsb + allocatesize_fsb;
1033			if ((temp = do_mod(startoffset_fsb, extsz)))
 
1034				e += temp;
1035			if ((temp = do_mod(e, extsz)))
 
1036				e += extsz - temp;
1037		} else {
1038			s = 0;
1039			e = allocatesize_fsb;
1040		}
1041
1042		/*
1043		 * The transaction reservation is limited to a 32-bit block
1044		 * count, hence we need to limit the number of blocks we are
1045		 * trying to reserve to avoid an overflow. We can't allocate
1046		 * more than @nimaps extents, and an extent is limited on disk
1047		 * to MAXEXTLEN (21 bits), so use that to enforce the limit.
 
1048		 */
1049		resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps));
 
1050		if (unlikely(rt)) {
1051			resrtextents = qblocks = resblks;
1052			resrtextents /= mp->m_sb.sb_rextsize;
1053			resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1054			quota_flag = XFS_QMOPT_RES_RTBLKS;
1055		} else {
1056			resrtextents = 0;
1057			resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks);
1058			quota_flag = XFS_QMOPT_RES_REGBLKS;
1059		}
1060
1061		/*
1062		 * Allocate and setup the transaction.
1063		 */
1064		tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
1065		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
1066					  resblks, resrtextents);
1067		/*
1068		 * Check for running out of space
1069		 */
1070		if (error) {
1071			/*
1072			 * Free the transaction structure.
1073			 */
1074			ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1075			xfs_trans_cancel(tp, 0);
1076			break;
1077		}
1078		xfs_ilock(ip, XFS_ILOCK_EXCL);
1079		error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
1080						      0, quota_flag);
1081		if (error)
1082			goto error1;
1083
1084		xfs_trans_ijoin(tp, ip, 0);
1085
1086		xfs_bmap_init(&free_list, &firstfsb);
1087		error = xfs_bmapi_write(tp, ip, startoffset_fsb,
1088					allocatesize_fsb, alloc_type, &firstfsb,
1089					0, imapp, &nimaps, &free_list);
1090		if (error) {
1091			goto error0;
1092		}
1093
1094		/*
1095		 * Complete the transaction
 
 
 
 
 
 
1096		 */
1097		error = xfs_bmap_finish(&tp, &free_list, &committed);
1098		if (error) {
1099			goto error0;
1100		}
1101
1102		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1103		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1104		if (error) {
1105			break;
 
 
 
 
 
1106		}
1107
1108		allocated_fsb = imapp->br_blockcount;
 
1109
1110		if (nimaps == 0) {
1111			error = XFS_ERROR(ENOSPC);
1112			break;
1113		}
1114
1115		startoffset_fsb += allocated_fsb;
1116		allocatesize_fsb -= allocated_fsb;
1117	}
1118
1119	return error;
1120
1121error0:	/* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
1122	xfs_bmap_cancel(&free_list);
1123	xfs_trans_unreserve_quota_nblks(tp, ip, (long)qblocks, 0, quota_flag);
1124
1125error1:	/* Just cancel transaction */
1126	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1127	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1128	return error;
1129}
1130
1131/*
1132 * Zero file bytes between startoff and endoff inclusive.
1133 * The iolock is held exclusive and no blocks are buffered.
1134 *
1135 * This function is used by xfs_free_file_space() to zero
1136 * partial blocks when the range to free is not block aligned.
1137 * When unreserving space with boundaries that are not block
1138 * aligned we round up the start and round down the end
1139 * boundaries and then use this function to zero the parts of
1140 * the blocks that got dropped during the rounding.
1141 */
1142STATIC int
1143xfs_zero_remaining_bytes(
1144	xfs_inode_t		*ip,
1145	xfs_off_t		startoff,
1146	xfs_off_t		endoff)
1147{
1148	xfs_bmbt_irec_t		imap;
1149	xfs_fileoff_t		offset_fsb;
1150	xfs_off_t		lastoffset;
1151	xfs_off_t		offset;
1152	xfs_buf_t		*bp;
1153	xfs_mount_t		*mp = ip->i_mount;
1154	int			nimap;
1155	int			error = 0;
1156
1157	/*
1158	 * Avoid doing I/O beyond eof - it's not necessary
1159	 * since nothing can read beyond eof.  The space will
1160	 * be zeroed when the file is extended anyway.
1161	 */
1162	if (startoff >= XFS_ISIZE(ip))
1163		return 0;
1164
1165	if (endoff > XFS_ISIZE(ip))
1166		endoff = XFS_ISIZE(ip);
1167
1168	bp = xfs_buf_get_uncached(XFS_IS_REALTIME_INODE(ip) ?
1169					mp->m_rtdev_targp : mp->m_ddev_targp,
1170				  BTOBB(mp->m_sb.sb_blocksize), 0);
1171	if (!bp)
1172		return XFS_ERROR(ENOMEM);
1173
1174	xfs_buf_unlock(bp);
 
 
 
1175
1176	for (offset = startoff; offset <= endoff; offset = lastoffset + 1) {
1177		uint lock_mode;
 
1178
1179		offset_fsb = XFS_B_TO_FSBT(mp, offset);
1180		nimap = 1;
 
 
1181
1182		lock_mode = xfs_ilock_data_map_shared(ip);
1183		error = xfs_bmapi_read(ip, offset_fsb, 1, &imap, &nimap, 0);
1184		xfs_iunlock(ip, lock_mode);
 
1185
1186		if (error || nimap < 1)
1187			break;
1188		ASSERT(imap.br_blockcount >= 1);
1189		ASSERT(imap.br_startoff == offset_fsb);
1190		lastoffset = XFS_FSB_TO_B(mp, imap.br_startoff + 1) - 1;
1191		if (lastoffset > endoff)
1192			lastoffset = endoff;
1193		if (imap.br_startblock == HOLESTARTBLOCK)
1194			continue;
1195		ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1196		if (imap.br_state == XFS_EXT_UNWRITTEN)
1197			continue;
1198		XFS_BUF_UNDONE(bp);
1199		XFS_BUF_UNWRITE(bp);
1200		XFS_BUF_READ(bp);
1201		XFS_BUF_SET_ADDR(bp, xfs_fsb_to_db(ip, imap.br_startblock));
1202
1203		if (XFS_FORCED_SHUTDOWN(mp)) {
1204			error = XFS_ERROR(EIO);
1205			break;
1206		}
1207		xfs_buf_iorequest(bp);
1208		error = xfs_buf_iowait(bp);
1209		if (error) {
1210			xfs_buf_ioerror_alert(bp,
1211					"xfs_zero_remaining_bytes(read)");
1212			break;
1213		}
1214		memset(bp->b_addr +
1215			(offset - XFS_FSB_TO_B(mp, imap.br_startoff)),
1216		      0, lastoffset - offset + 1);
1217		XFS_BUF_UNDONE(bp);
1218		XFS_BUF_UNREAD(bp);
1219		XFS_BUF_WRITE(bp);
1220
1221		if (XFS_FORCED_SHUTDOWN(mp)) {
1222			error = XFS_ERROR(EIO);
1223			break;
1224		}
1225		xfs_buf_iorequest(bp);
1226		error = xfs_buf_iowait(bp);
1227		if (error) {
1228			xfs_buf_ioerror_alert(bp,
1229					"xfs_zero_remaining_bytes(write)");
1230			break;
1231		}
1232	}
1233	xfs_buf_free(bp);
1234	return error;
1235}
1236
1237int
1238xfs_free_file_space(
1239	struct xfs_inode	*ip,
1240	xfs_off_t		offset,
1241	xfs_off_t		len)
1242{
1243	int			committed;
1244	int			done;
1245	xfs_fileoff_t		endoffset_fsb;
1246	int			error;
1247	xfs_fsblock_t		firstfsb;
1248	xfs_bmap_free_t		free_list;
1249	xfs_bmbt_irec_t		imap;
1250	xfs_off_t		ioffset;
1251	xfs_extlen_t		mod=0;
1252	xfs_mount_t		*mp;
1253	int			nimap;
1254	uint			resblks;
1255	xfs_off_t		rounding;
1256	int			rt;
1257	xfs_fileoff_t		startoffset_fsb;
1258	xfs_trans_t		*tp;
1259
1260	mp = ip->i_mount;
1261
1262	trace_xfs_free_file_space(ip);
1263
1264	error = xfs_qm_dqattach(ip, 0);
1265	if (error)
1266		return error;
1267
1268	error = 0;
1269	if (len <= 0)	/* if nothing being freed */
 
 
 
 
 
 
 
 
1270		return error;
1271	rt = XFS_IS_REALTIME_INODE(ip);
1272	startoffset_fsb	= XFS_B_TO_FSB(mp, offset);
1273	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
1274
1275	/* wait for the completion of any pending DIOs */
1276	inode_dio_wait(VFS_I(ip));
1277
1278	rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
1279	ioffset = offset & ~(rounding - 1);
1280	error = -filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
1281					      ioffset, -1);
1282	if (error)
1283		goto out;
1284	truncate_pagecache_range(VFS_I(ip), ioffset, -1);
1285
1286	/*
1287	 * Need to zero the stuff we're not freeing, on disk.
1288	 * If it's a realtime file & can't use unwritten extents then we
1289	 * actually need to zero the extent edges.  Otherwise xfs_bunmapi
1290	 * will take care of it for us.
1291	 */
1292	if (rt && !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
1293		nimap = 1;
1294		error = xfs_bmapi_read(ip, startoffset_fsb, 1,
1295					&imap, &nimap, 0);
1296		if (error)
1297			goto out;
1298		ASSERT(nimap == 0 || nimap == 1);
1299		if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1300			xfs_daddr_t	block;
1301
1302			ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1303			block = imap.br_startblock;
1304			mod = do_div(block, mp->m_sb.sb_rextsize);
1305			if (mod)
1306				startoffset_fsb += mp->m_sb.sb_rextsize - mod;
1307		}
1308		nimap = 1;
1309		error = xfs_bmapi_read(ip, endoffset_fsb - 1, 1,
1310					&imap, &nimap, 0);
1311		if (error)
1312			goto out;
1313		ASSERT(nimap == 0 || nimap == 1);
1314		if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1315			ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1316			mod++;
1317			if (mod && (mod != mp->m_sb.sb_rextsize))
1318				endoffset_fsb -= mod;
1319		}
1320	}
1321	if ((done = (endoffset_fsb <= startoffset_fsb)))
1322		/*
1323		 * One contiguous piece to clear
1324		 */
1325		error = xfs_zero_remaining_bytes(ip, offset, offset + len - 1);
1326	else {
1327		/*
1328		 * Some full blocks, possibly two pieces to clear
1329		 */
1330		if (offset < XFS_FSB_TO_B(mp, startoffset_fsb))
1331			error = xfs_zero_remaining_bytes(ip, offset,
1332				XFS_FSB_TO_B(mp, startoffset_fsb) - 1);
1333		if (!error &&
1334		    XFS_FSB_TO_B(mp, endoffset_fsb) < offset + len)
1335			error = xfs_zero_remaining_bytes(ip,
1336				XFS_FSB_TO_B(mp, endoffset_fsb),
1337				offset + len - 1);
1338	}
1339
1340	/*
1341	 * free file space until done or until there is an error
 
 
 
1342	 */
1343	resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1344	while (!error && !done) {
1345
1346		/*
1347		 * allocate and setup the transaction. Allow this
1348		 * transaction to dip into the reserve blocks to ensure
1349		 * the freeing of the space succeeds at ENOSPC.
1350		 */
1351		tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
1352		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write, resblks, 0);
1353
1354		/*
1355		 * check for running out of space
1356		 */
1357		if (error) {
1358			/*
1359			 * Free the transaction structure.
1360			 */
1361			ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1362			xfs_trans_cancel(tp, 0);
1363			break;
1364		}
1365		xfs_ilock(ip, XFS_ILOCK_EXCL);
1366		error = xfs_trans_reserve_quota(tp, mp,
1367				ip->i_udquot, ip->i_gdquot, ip->i_pdquot,
1368				resblks, 0, XFS_QMOPT_RES_REGBLKS);
1369		if (error)
1370			goto error1;
1371
1372		xfs_trans_ijoin(tp, ip, 0);
1373
1374		/*
1375		 * issue the bunmapi() call to free the blocks
1376		 */
1377		xfs_bmap_init(&free_list, &firstfsb);
1378		error = xfs_bunmapi(tp, ip, startoffset_fsb,
1379				  endoffset_fsb - startoffset_fsb,
1380				  0, 2, &firstfsb, &free_list, &done);
1381		if (error) {
1382			goto error0;
1383		}
1384
1385		/*
1386		 * complete the transaction
1387		 */
1388		error = xfs_bmap_finish(&tp, &free_list, &committed);
1389		if (error) {
1390			goto error0;
1391		}
1392
1393		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1394		xfs_iunlock(ip, XFS_ILOCK_EXCL);
 
 
 
 
 
 
 
1395	}
1396
1397 out:
1398	return error;
1399
1400 error0:
1401	xfs_bmap_cancel(&free_list);
1402 error1:
1403	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1404	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1405	goto out;
1406}
1407
1408
1409int
1410xfs_zero_file_space(
1411	struct xfs_inode	*ip,
1412	xfs_off_t		offset,
1413	xfs_off_t		len)
1414{
1415	struct xfs_mount	*mp = ip->i_mount;
1416	uint			granularity;
1417	xfs_off_t		start_boundary;
1418	xfs_off_t		end_boundary;
1419	int			error;
1420
1421	trace_xfs_zero_file_space(ip);
1422
1423	granularity = max_t(uint, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
1424
1425	/*
1426	 * Round the range of extents we are going to convert inwards.  If the
1427	 * offset is aligned, then it doesn't get changed so we zero from the
1428	 * start of the block offset points to.
1429	 */
1430	start_boundary = round_up(offset, granularity);
1431	end_boundary = round_down(offset + len, granularity);
1432
1433	ASSERT(start_boundary >= offset);
1434	ASSERT(end_boundary <= offset + len);
1435
1436	if (start_boundary < end_boundary - 1) {
1437		/*
1438		 * punch out delayed allocation blocks and the page cache over
1439		 * the conversion range
1440		 */
1441		xfs_ilock(ip, XFS_ILOCK_EXCL);
1442		error = xfs_bmap_punch_delalloc_range(ip,
1443				XFS_B_TO_FSBT(mp, start_boundary),
1444				XFS_B_TO_FSB(mp, end_boundary - start_boundary));
1445		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1446		truncate_pagecache_range(VFS_I(ip), start_boundary,
1447					 end_boundary - 1);
1448
1449		/* convert the blocks */
1450		error = xfs_alloc_file_space(ip, start_boundary,
1451					end_boundary - start_boundary - 1,
1452					XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT);
1453		if (error)
1454			goto out;
 
1455
1456		/* We've handled the interior of the range, now for the edges */
1457		if (start_boundary != offset) {
1458			error = xfs_iozero(ip, offset, start_boundary - offset);
1459			if (error)
1460				goto out;
1461		}
 
 
 
 
 
 
1462
1463		if (end_boundary != offset + len)
1464			error = xfs_iozero(ip, end_boundary,
1465					   offset + len - end_boundary);
 
 
 
 
1466
1467	} else {
1468		/*
1469		 * It's either a sub-granularity range or the range spanned lies
1470		 * partially across two adjacent blocks.
1471		 */
1472		error = xfs_iozero(ip, offset, len);
 
 
 
 
1473	}
1474
1475out:
1476	return error;
1477
1478}
1479
1480/*
1481 * xfs_collapse_file_space()
1482 *	This routine frees disk space and shift extent for the given file.
1483 *	The first thing we do is to free data blocks in the specified range
1484 *	by calling xfs_free_file_space(). It would also sync dirty data
1485 *	and invalidate page cache over the region on which collapse range
1486 *	is working. And Shift extent records to the left to cover a hole.
1487 * RETURNS:
1488 *	0 on success
1489 *	errno on error
1490 *
1491 */
1492int
1493xfs_collapse_file_space(
1494	struct xfs_inode	*ip,
1495	xfs_off_t		offset,
1496	xfs_off_t		len)
1497{
1498	int			done = 0;
1499	struct xfs_mount	*mp = ip->i_mount;
1500	struct xfs_trans	*tp;
1501	int			error;
1502	xfs_extnum_t		current_ext = 0;
1503	struct xfs_bmap_free	free_list;
1504	xfs_fsblock_t		first_block;
1505	int			committed;
1506	xfs_fileoff_t		start_fsb;
1507	xfs_fileoff_t		shift_fsb;
1508
1509	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1510
1511	trace_xfs_collapse_file_space(ip);
1512
1513	start_fsb = XFS_B_TO_FSB(mp, offset + len);
1514	shift_fsb = XFS_B_TO_FSB(mp, len);
1515
1516	error = xfs_free_file_space(ip, offset, len);
1517	if (error)
1518		return error;
1519
1520	while (!error && !done) {
1521		tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
1522		tp->t_flags |= XFS_TRANS_RESERVE;
1523		/*
1524		 * We would need to reserve permanent block for transaction.
1525		 * This will come into picture when after shifting extent into
1526		 * hole we found that adjacent extents can be merged which
1527		 * may lead to freeing of a block during record update.
1528		 */
1529		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_write,
1530				XFS_DIOSTRAT_SPACE_RES(mp, 0), 0);
1531		if (error) {
1532			ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1533			xfs_trans_cancel(tp, 0);
 
 
 
1534			break;
1535		}
1536
1537		xfs_ilock(ip, XFS_ILOCK_EXCL);
1538		error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot,
1539				ip->i_gdquot, ip->i_pdquot,
1540				XFS_DIOSTRAT_SPACE_RES(mp, 0), 0,
1541				XFS_QMOPT_RES_REGBLKS);
1542		if (error)
1543			goto out;
 
1544
1545		xfs_trans_ijoin(tp, ip, 0);
 
 
1546
1547		xfs_bmap_init(&free_list, &first_block);
 
 
 
 
1548
1549		/*
1550		 * We are using the write transaction in which max 2 bmbt
1551		 * updates are allowed
1552		 */
1553		error = xfs_bmap_shift_extents(tp, ip, &done, start_fsb,
1554					       shift_fsb, &current_ext,
1555					       &first_block, &free_list,
1556					       XFS_BMAP_MAX_SHIFT_EXTENTS);
1557		if (error)
1558			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1559
1560		error = xfs_bmap_finish(&tp, &free_list, &committed);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1561		if (error)
1562			goto out;
1563
1564		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1565		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1566	}
 
 
1567
 
 
1568	return error;
1569
1570out:
1571	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1572	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1573	return error;
1574}
1575
1576/*
1577 * We need to check that the format of the data fork in the temporary inode is
1578 * valid for the target inode before doing the swap. This is not a problem with
1579 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized
1580 * data fork depending on the space the attribute fork is taking so we can get
1581 * invalid formats on the target inode.
1582 *
1583 * E.g. target has space for 7 extents in extent format, temp inode only has
1584 * space for 6.  If we defragment down to 7 extents, then the tmp format is a
1585 * btree, but when swapped it needs to be in extent format. Hence we can't just
1586 * blindly swap data forks on attr2 filesystems.
1587 *
1588 * Note that we check the swap in both directions so that we don't end up with
1589 * a corrupt temporary inode, either.
1590 *
1591 * Note that fixing the way xfs_fsr sets up the attribute fork in the source
1592 * inode will prevent this situation from occurring, so all we do here is
1593 * reject and log the attempt. basically we are putting the responsibility on
1594 * userspace to get this right.
1595 */
1596static int
1597xfs_swap_extents_check_format(
1598	xfs_inode_t	*ip,	/* target inode */
1599	xfs_inode_t	*tip)	/* tmp inode */
1600{
 
 
 
 
 
 
 
 
 
1601
1602	/* Should never get a local format */
1603	if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL ||
1604	    tip->i_d.di_format == XFS_DINODE_FMT_LOCAL)
1605		return EINVAL;
1606
1607	/*
1608	 * if the target inode has less extents that then temporary inode then
1609	 * why did userspace call us?
1610	 */
1611	if (ip->i_d.di_nextents < tip->i_d.di_nextents)
1612		return EINVAL;
 
 
 
 
 
 
 
1613
1614	/*
1615	 * if the target inode is in extent form and the temp inode is in btree
1616	 * form then we will end up with the target inode in the wrong format
1617	 * as we already know there are less extents in the temp inode.
1618	 */
1619	if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1620	    tip->i_d.di_format == XFS_DINODE_FMT_BTREE)
1621		return EINVAL;
1622
1623	/* Check temp in extent form to max in target */
1624	if (tip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1625	    XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) >
1626			XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1627		return EINVAL;
1628
1629	/* Check target in extent form to max in temp */
1630	if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1631	    XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) >
1632			XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1633		return EINVAL;
1634
1635	/*
1636	 * If we are in a btree format, check that the temp root block will fit
1637	 * in the target and that it has enough extents to be in btree format
1638	 * in the target.
1639	 *
1640	 * Note that we have to be careful to allow btree->extent conversions
1641	 * (a common defrag case) which will occur when the temp inode is in
1642	 * extent format...
1643	 */
1644	if (tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1645		if (XFS_IFORK_BOFF(ip) &&
1646		    XFS_BMAP_BMDR_SPACE(tip->i_df.if_broot) > XFS_IFORK_BOFF(ip))
1647			return EINVAL;
1648		if (XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) <=
1649		    XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1650			return EINVAL;
1651	}
1652
1653	/* Reciprocal target->temp btree format checks */
1654	if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1655		if (XFS_IFORK_BOFF(tip) &&
1656		    XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > XFS_IFORK_BOFF(tip))
1657			return EINVAL;
1658		if (XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) <=
1659		    XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1660			return EINVAL;
1661	}
1662
1663	return 0;
1664}
1665
1666int
1667xfs_swap_extents(
1668	xfs_inode_t	*ip,	/* target inode */
1669	xfs_inode_t	*tip,	/* tmp inode */
1670	xfs_swapext_t	*sxp)
1671{
1672	xfs_mount_t	*mp = ip->i_mount;
1673	xfs_trans_t	*tp;
1674	xfs_bstat_t	*sbp = &sxp->sx_stat;
1675	xfs_ifork_t	*tempifp, *ifp, *tifp;
1676	int		src_log_flags, target_log_flags;
1677	int		error = 0;
1678	int		aforkblks = 0;
1679	int		taforkblks = 0;
1680	__uint64_t	tmp;
1681
1682	tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL);
1683	if (!tempifp) {
1684		error = XFS_ERROR(ENOMEM);
1685		goto out;
1686	}
1687
1688	/*
1689	 * we have to do two separate lock calls here to keep lockdep
1690	 * happy. If we try to get all the locks in one call, lock will
1691	 * report false positives when we drop the ILOCK and regain them
1692	 * below.
1693	 */
1694	xfs_lock_two_inodes(ip, tip, XFS_IOLOCK_EXCL);
1695	xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);
1696
1697	/* Verify that both files have the same format */
1698	if ((ip->i_d.di_mode & S_IFMT) != (tip->i_d.di_mode & S_IFMT)) {
1699		error = XFS_ERROR(EINVAL);
1700		goto out_unlock;
1701	}
1702
1703	/* Verify both files are either real-time or non-realtime */
1704	if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
1705		error = XFS_ERROR(EINVAL);
1706		goto out_unlock;
1707	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1708
1709	error = -filemap_write_and_wait(VFS_I(tip)->i_mapping);
1710	if (error)
1711		goto out_unlock;
1712	truncate_pagecache_range(VFS_I(tip), 0, -1);
1713
1714	/* Verify O_DIRECT for ftmp */
1715	if (VN_CACHED(VFS_I(tip)) != 0) {
1716		error = XFS_ERROR(EINVAL);
1717		goto out_unlock;
1718	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1719
1720	/* Verify all data are being swapped */
1721	if (sxp->sx_offset != 0 ||
1722	    sxp->sx_length != ip->i_d.di_size ||
1723	    sxp->sx_length != tip->i_d.di_size) {
1724		error = XFS_ERROR(EFAULT);
1725		goto out_unlock;
1726	}
1727
1728	trace_xfs_swap_extent_before(ip, 0);
1729	trace_xfs_swap_extent_before(tip, 1);
1730
1731	/* check inode formats now that data is flushed */
1732	error = xfs_swap_extents_check_format(ip, tip);
1733	if (error) {
1734		xfs_notice(mp,
1735		    "%s: inode 0x%llx format is incompatible for exchanging.",
1736				__func__, ip->i_ino);
1737		goto out_unlock;
1738	}
1739
1740	/*
1741	 * Compare the current change & modify times with that
1742	 * passed in.  If they differ, we abort this swap.
1743	 * This is the mechanism used to ensure the calling
1744	 * process that the file was not changed out from
1745	 * under it.
1746	 */
1747	if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) ||
1748	    (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) ||
1749	    (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) ||
1750	    (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) {
1751		error = XFS_ERROR(EBUSY);
1752		goto out_unlock;
1753	}
1754
1755	/* We need to fail if the file is memory mapped.  Once we have tossed
1756	 * all existing pages, the page fault will have no option
1757	 * but to go to the filesystem for pages. By making the page fault call
1758	 * vop_read (or write in the case of autogrow) they block on the iolock
1759	 * until we have switched the extents.
1760	 */
1761	if (VN_MAPPED(VFS_I(ip))) {
1762		error = XFS_ERROR(EBUSY);
1763		goto out_unlock;
1764	}
1765
1766	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1767	xfs_iunlock(tip, XFS_ILOCK_EXCL);
 
 
1768
1769	/*
1770	 * There is a race condition here since we gave up the
1771	 * ilock.  However, the data fork will not change since
1772	 * we have the iolock (locked for truncation too) so we
1773	 * are safe.  We don't really care if non-io related
1774	 * fields change.
1775	 */
1776	truncate_pagecache_range(VFS_I(ip), 0, -1);
1777
1778	tp = xfs_trans_alloc(mp, XFS_TRANS_SWAPEXT);
1779	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ichange, 0, 0);
1780	if (error) {
1781		xfs_iunlock(ip,  XFS_IOLOCK_EXCL);
1782		xfs_iunlock(tip, XFS_IOLOCK_EXCL);
1783		xfs_trans_cancel(tp, 0);
1784		goto out;
1785	}
1786	xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1787
1788	/*
1789	 * Count the number of extended attribute blocks
1790	 */
1791	if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
1792	     (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
1793		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &aforkblks);
 
1794		if (error)
1795			goto out_trans_cancel;
1796	}
1797	if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
1798	     (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
1799		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
1800			&taforkblks);
1801		if (error)
1802			goto out_trans_cancel;
1803	}
1804
1805	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
1806	xfs_trans_ijoin(tp, tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
1807
1808	/*
1809	 * Before we've swapped the forks, lets set the owners of the forks
1810	 * appropriately. We have to do this as we are demand paging the btree
1811	 * buffers, and so the validation done on read will expect the owner
1812	 * field to be correctly set. Once we change the owners, we can swap the
1813	 * inode forks.
1814	 *
1815	 * Note the trickiness in setting the log flags - we set the owner log
1816	 * flag on the opposite inode (i.e. the inode we are setting the new
1817	 * owner to be) because once we swap the forks and log that, log
1818	 * recovery is going to see the fork as owned by the swapped inode,
1819	 * not the pre-swapped inodes.
1820	 */
1821	src_log_flags = XFS_ILOG_CORE;
1822	target_log_flags = XFS_ILOG_CORE;
1823	if (ip->i_d.di_version == 3 &&
1824	    ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1825		target_log_flags |= XFS_ILOG_DOWNER;
1826		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK,
1827					      tip->i_ino, NULL);
1828		if (error)
1829			goto out_trans_cancel;
1830	}
1831
1832	if (tip->i_d.di_version == 3 &&
1833	    tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1834		src_log_flags |= XFS_ILOG_DOWNER;
1835		error = xfs_bmbt_change_owner(tp, tip, XFS_DATA_FORK,
1836					      ip->i_ino, NULL);
1837		if (error)
1838			goto out_trans_cancel;
1839	}
1840
1841	/*
1842	 * Swap the data forks of the inodes
1843	 */
1844	ifp = &ip->i_df;
1845	tifp = &tip->i_df;
1846	*tempifp = *ifp;	/* struct copy */
1847	*ifp = *tifp;		/* struct copy */
1848	*tifp = *tempifp;	/* struct copy */
1849
1850	/*
1851	 * Fix the on-disk inode values
1852	 */
1853	tmp = (__uint64_t)ip->i_d.di_nblocks;
1854	ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
1855	tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;
1856
1857	tmp = (__uint64_t) ip->i_d.di_nextents;
1858	ip->i_d.di_nextents = tip->i_d.di_nextents;
1859	tip->i_d.di_nextents = tmp;
1860
1861	tmp = (__uint64_t) ip->i_d.di_format;
1862	ip->i_d.di_format = tip->i_d.di_format;
1863	tip->i_d.di_format = tmp;
1864
1865	/*
1866	 * The extents in the source inode could still contain speculative
1867	 * preallocation beyond EOF (e.g. the file is open but not modified
1868	 * while defrag is in progress). In that case, we need to copy over the
1869	 * number of delalloc blocks the data fork in the source inode is
1870	 * tracking beyond EOF so that when the fork is truncated away when the
1871	 * temporary inode is unlinked we don't underrun the i_delayed_blks
1872	 * counter on that inode.
1873	 */
1874	ASSERT(tip->i_delayed_blks == 0);
1875	tip->i_delayed_blks = ip->i_delayed_blks;
1876	ip->i_delayed_blks = 0;
1877
1878	switch (ip->i_d.di_format) {
1879	case XFS_DINODE_FMT_EXTENTS:
1880		/* If the extents fit in the inode, fix the
1881		 * pointer.  Otherwise it's already NULL or
1882		 * pointing to the extent.
1883		 */
1884		if (ip->i_d.di_nextents <= XFS_INLINE_EXTS) {
1885			ifp->if_u1.if_extents =
1886				ifp->if_u2.if_inline_ext;
1887		}
1888		src_log_flags |= XFS_ILOG_DEXT;
1889		break;
1890	case XFS_DINODE_FMT_BTREE:
1891		ASSERT(ip->i_d.di_version < 3 ||
1892		       (src_log_flags & XFS_ILOG_DOWNER));
1893		src_log_flags |= XFS_ILOG_DBROOT;
1894		break;
1895	}
1896
1897	switch (tip->i_d.di_format) {
1898	case XFS_DINODE_FMT_EXTENTS:
1899		/* If the extents fit in the inode, fix the
1900		 * pointer.  Otherwise it's already NULL or
1901		 * pointing to the extent.
1902		 */
1903		if (tip->i_d.di_nextents <= XFS_INLINE_EXTS) {
1904			tifp->if_u1.if_extents =
1905				tifp->if_u2.if_inline_ext;
1906		}
1907		target_log_flags |= XFS_ILOG_DEXT;
1908		break;
1909	case XFS_DINODE_FMT_BTREE:
1910		target_log_flags |= XFS_ILOG_DBROOT;
1911		ASSERT(tip->i_d.di_version < 3 ||
1912		       (target_log_flags & XFS_ILOG_DOWNER));
1913		break;
1914	}
1915
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1916	xfs_trans_log_inode(tp, ip,  src_log_flags);
1917	xfs_trans_log_inode(tp, tip, target_log_flags);
1918
1919	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1920	 * If this is a synchronous mount, make sure that the
1921	 * transaction goes to disk before returning to the user.
1922	 */
1923	if (mp->m_flags & XFS_MOUNT_WSYNC)
1924		xfs_trans_set_sync(tp);
1925
1926	error = xfs_trans_commit(tp, 0);
1927
1928	trace_xfs_swap_extent_after(ip, 0);
1929	trace_xfs_swap_extent_after(tip, 1);
1930out:
1931	kmem_free(tempifp);
1932	return error;
1933
 
 
 
1934out_unlock:
1935	xfs_iunlock(ip,  XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
1936	xfs_iunlock(tip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
1937	goto out;
 
1938
1939out_trans_cancel:
1940	xfs_trans_cancel(tp, 0);
1941	goto out_unlock;
1942}
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   4 * Copyright (c) 2012 Red Hat, Inc.
   5 * All Rights Reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
   6 */
   7#include "xfs.h"
   8#include "xfs_fs.h"
   9#include "xfs_shared.h"
  10#include "xfs_format.h"
  11#include "xfs_log_format.h"
  12#include "xfs_trans_resv.h"
  13#include "xfs_bit.h"
 
 
  14#include "xfs_mount.h"
  15#include "xfs_defer.h"
  16#include "xfs_inode.h"
  17#include "xfs_btree.h"
  18#include "xfs_trans.h"
 
  19#include "xfs_alloc.h"
  20#include "xfs_bmap.h"
  21#include "xfs_bmap_util.h"
  22#include "xfs_bmap_btree.h"
  23#include "xfs_rtalloc.h"
  24#include "xfs_error.h"
  25#include "xfs_quota.h"
  26#include "xfs_trans_space.h"
  27#include "xfs_trace.h"
  28#include "xfs_icache.h"
  29#include "xfs_iomap.h"
  30#include "xfs_reflink.h"
  31#include "xfs_rtbitmap.h"
  32#include "xfs_rtgroup.h"
  33
  34/* Kernel only BMAP related definitions and functions */
  35
  36/*
  37 * Convert the given file system block to a disk block.  We have to treat it
  38 * differently based on whether the file is a real time file or not, because the
  39 * bmap code does.
  40 */
  41xfs_daddr_t
  42xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
  43{
  44	if (XFS_IS_REALTIME_INODE(ip))
  45		return xfs_rtb_to_daddr(ip->i_mount, fsb);
  46	return XFS_FSB_TO_DADDR(ip->i_mount, fsb);
  47}
  48
  49/*
  50 * Routine to zero an extent on disk allocated to the specific inode.
 
 
 
 
 
 
  51 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  52int
  53xfs_zero_extent(
  54	struct xfs_inode	*ip,
  55	xfs_fsblock_t		start_fsb,
  56	xfs_off_t		count_fsb)
  57{
  58	return blkdev_issue_zeroout(xfs_inode_buftarg(ip)->bt_bdev,
  59			xfs_fsb_to_db(ip, start_fsb),
  60			XFS_FSB_TO_BB(ip->i_mount, count_fsb),
  61			GFP_KERNEL, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  62}
  63
  64/*
  65 * Extent tree block counting routines.
  66 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  67
  68/*
  69 * Count leaf blocks given a range of extent records.  Delayed allocation
  70 * extents are not counted towards the totals.
 
  71 */
  72xfs_extnum_t
  73xfs_bmap_count_leaves(
  74	struct xfs_ifork	*ifp,
  75	xfs_filblks_t		*count)
  76{
  77	struct xfs_iext_cursor	icur;
  78	struct xfs_bmbt_irec	got;
  79	xfs_extnum_t		numrecs = 0;
 
  80
  81	for_each_xfs_iext(ifp, &icur, &got) {
  82		if (!isnullstartblock(got.br_startblock)) {
  83			*count += got.br_blockcount;
  84			numrecs++;
  85		}
  86	}
  87
  88	return numrecs;
 
 
 
 
 
  89}
  90
  91/*
  92 * Count fsblocks of the given fork.  Delayed allocation extents are
  93 * not counted towards the totals.
 
  94 */
  95int
  96xfs_bmap_count_blocks(
  97	struct xfs_trans	*tp,
  98	struct xfs_inode	*ip,
 
  99	int			whichfork,
 100	xfs_extnum_t		*nextents,
 101	xfs_filblks_t		*count)
 102{
 103	struct xfs_mount	*mp = ip->i_mount;
 104	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
 105	struct xfs_btree_cur	*cur;
 106	xfs_filblks_t		btblocks = 0;
 107	int			error;
 108
 109	*nextents = 0;
 110	*count = 0;
 
 111
 112	if (!ifp)
 113		return 0;
 
 114
 115	switch (ifp->if_format) {
 116	case XFS_DINODE_FMT_BTREE:
 117		error = xfs_iread_extents(tp, ip, whichfork);
 118		if (error)
 119			return error;
 120
 121		cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
 122		error = xfs_btree_count_blocks(cur, &btblocks);
 123		xfs_btree_del_cursor(cur, error);
 124		if (error)
 125			return error;
 
 
 
 
 
 
 
 
 
 
 
 
 126
 127		/*
 128		 * xfs_btree_count_blocks includes the root block contained in
 129		 * the inode fork in @btblocks, so subtract one because we're
 130		 * only interested in allocated disk blocks.
 131		 */
 132		*count += btblocks - 1;
 133
 134		fallthrough;
 135	case XFS_DINODE_FMT_EXTENTS:
 136		*nextents = xfs_bmap_count_leaves(ifp, count);
 137		break;
 
 
 
 
 
 
 138	}
 139
 140	return 0;
 141}
 142
 143static int
 144xfs_getbmap_report_one(
 145	struct xfs_inode	*ip,
 146	struct getbmapx		*bmv,
 147	struct kgetbmap		*out,
 148	int64_t			bmv_end,
 149	struct xfs_bmbt_irec	*got)
 
 
 
 
 
 150{
 151	struct kgetbmap		*p = out + bmv->bmv_entries;
 152	bool			shared = false;
 153	int			error;
 
 
 
 
 
 
 
 154
 155	error = xfs_reflink_trim_around_shared(ip, got, &shared);
 
 156	if (error)
 157		return error;
 
 
 158
 159	if (isnullstartblock(got->br_startblock) ||
 160	    got->br_startblock == DELAYSTARTBLOCK) {
 161		/*
 162		 * Take the flush completion as being a point-in-time snapshot
 163		 * where there are no delalloc extents, and if any new ones
 164		 * have been created racily, just skip them as being 'after'
 165		 * the flush and so don't get reported.
 166		 */
 167		if (!(bmv->bmv_iflags & BMV_IF_DELALLOC))
 168			return 0;
 
 
 
 
 169
 170		p->bmv_oflags |= BMV_OF_DELALLOC;
 171		p->bmv_block = -2;
 
 
 
 
 
 
 
 
 
 172	} else {
 173		p->bmv_block = xfs_fsb_to_db(ip, got->br_startblock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 174	}
 175
 176	if (got->br_state == XFS_EXT_UNWRITTEN &&
 177	    (bmv->bmv_iflags & BMV_IF_PREALLOC))
 178		p->bmv_oflags |= BMV_OF_PREALLOC;
 179
 180	if (shared)
 181		p->bmv_oflags |= BMV_OF_SHARED;
 182
 183	p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, got->br_startoff);
 184	p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, got->br_blockcount);
 185
 186	bmv->bmv_offset = p->bmv_offset + p->bmv_length;
 187	bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset);
 188	bmv->bmv_entries++;
 189	return 0;
 190}
 191
 192static void
 193xfs_getbmap_report_hole(
 194	struct xfs_inode	*ip,
 195	struct getbmapx		*bmv,
 196	struct kgetbmap		*out,
 197	int64_t			bmv_end,
 198	xfs_fileoff_t		bno,
 199	xfs_fileoff_t		end)
 200{
 201	struct kgetbmap		*p = out + bmv->bmv_entries;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 202
 203	if (bmv->bmv_iflags & BMV_IF_NO_HOLES)
 204		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 205
 206	p->bmv_block = -1;
 207	p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, bno);
 208	p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, end - bno);
 209
 210	bmv->bmv_offset = p->bmv_offset + p->bmv_length;
 211	bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset);
 212	bmv->bmv_entries++;
 213}
 214
 215static inline bool
 216xfs_getbmap_full(
 217	struct getbmapx		*bmv)
 218{
 219	return bmv->bmv_length == 0 || bmv->bmv_entries >= bmv->bmv_count - 1;
 220}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 221
 222static bool
 223xfs_getbmap_next_rec(
 224	struct xfs_bmbt_irec	*rec,
 225	xfs_fileoff_t		total_end)
 226{
 227	xfs_fileoff_t		end = rec->br_startoff + rec->br_blockcount;
 228
 229	if (end == total_end)
 230		return false;
 231
 232	rec->br_startoff += rec->br_blockcount;
 233	if (!isnullstartblock(rec->br_startblock) &&
 234	    rec->br_startblock != DELAYSTARTBLOCK)
 235		rec->br_startblock += rec->br_blockcount;
 236	rec->br_blockcount = total_end - end;
 237	return true;
 238}
 239
 240/*
 241 * Get inode's extents as described in bmv, and format for output.
 242 * Calls formatter to fill the user's buffer until all extents
 243 * are mapped, until the passed-in bmv->bmv_count slots have
 244 * been filled, or until the formatter short-circuits the loop,
 245 * if it is tracking filled-in extents on its own.
 246 */
 247int						/* error code */
 248xfs_getbmap(
 249	struct xfs_inode	*ip,
 250	struct getbmapx		*bmv,		/* user bmap structure */
 251	struct kgetbmap		*out)
 
 252{
 253	struct xfs_mount	*mp = ip->i_mount;
 254	int			iflags = bmv->bmv_iflags;
 255	int			whichfork, lock, error = 0;
 256	int64_t			bmv_end, max_len;
 257	xfs_fileoff_t		bno, first_bno;
 258	struct xfs_ifork	*ifp;
 259	struct xfs_bmbt_irec	got, rec;
 260	xfs_filblks_t		len;
 261	struct xfs_iext_cursor	icur;
 262
 263	if (bmv->bmv_iflags & ~BMV_IF_VALID)
 264		return -EINVAL;
 265#ifndef DEBUG
 266	/* Only allow CoW fork queries if we're debugging. */
 267	if (iflags & BMV_IF_COWFORK)
 268		return -EINVAL;
 269#endif
 270	if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK))
 271		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 272
 273	if (bmv->bmv_length < -1)
 274		return -EINVAL;
 275	bmv->bmv_entries = 0;
 276	if (bmv->bmv_length == 0)
 
 
 277		return 0;
 
 
 
 278
 279	if (iflags & BMV_IF_ATTRFORK)
 280		whichfork = XFS_ATTR_FORK;
 281	else if (iflags & BMV_IF_COWFORK)
 282		whichfork = XFS_COW_FORK;
 283	else
 284		whichfork = XFS_DATA_FORK;
 285
 286	xfs_ilock(ip, XFS_IOLOCK_SHARED);
 287	switch (whichfork) {
 288	case XFS_ATTR_FORK:
 289		lock = xfs_ilock_attr_map_shared(ip);
 290		if (!xfs_inode_has_attr_fork(ip))
 291			goto out_unlock_ilock;
 292
 293		max_len = 1LL << 32;
 294		break;
 295	case XFS_COW_FORK:
 296		lock = XFS_ILOCK_SHARED;
 297		xfs_ilock(ip, lock);
 298
 299		/* No CoW fork? Just return */
 300		if (!xfs_ifork_ptr(ip, whichfork))
 301			goto out_unlock_ilock;
 302
 303		if (xfs_get_cowextsz_hint(ip))
 304			max_len = mp->m_super->s_maxbytes;
 305		else
 306			max_len = XFS_ISIZE(ip);
 307		break;
 308	case XFS_DATA_FORK:
 309		if (!(iflags & BMV_IF_DELALLOC) &&
 310		    (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_disk_size)) {
 311			error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
 312			if (error)
 313				goto out_unlock_iolock;
 314
 315			/*
 316			 * Even after flushing the inode, there can still be
 317			 * delalloc blocks on the inode beyond EOF due to
 318			 * speculative preallocation.  These are not removed
 319			 * until the release function is called or the inode
 320			 * is inactivated.  Hence we cannot assert here that
 321			 * ip->i_delayed_blks == 0.
 322			 */
 323		}
 324
 325		if (xfs_get_extsz_hint(ip) ||
 326		    (ip->i_diflags & XFS_DIFLAG_PREALLOC))
 327			max_len = mp->m_super->s_maxbytes;
 328		else
 329			max_len = XFS_ISIZE(ip);
 330
 331		lock = xfs_ilock_data_map_shared(ip);
 332		break;
 
 333	}
 334
 335	ifp = xfs_ifork_ptr(ip, whichfork);
 
 
 
 
 
 
 
 
 
 336
 337	switch (ifp->if_format) {
 338	case XFS_DINODE_FMT_EXTENTS:
 339	case XFS_DINODE_FMT_BTREE:
 340		break;
 341	case XFS_DINODE_FMT_LOCAL:
 342		/* Local format inode forks report no extents. */
 343		goto out_unlock_ilock;
 344	default:
 345		error = -EINVAL;
 346		goto out_unlock_ilock;
 
 
 
 
 
 
 
 347	}
 348
 349	if (bmv->bmv_length == -1) {
 350		max_len = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, max_len));
 351		bmv->bmv_length = max(0LL, max_len - bmv->bmv_offset);
 352	}
 353
 354	bmv_end = bmv->bmv_offset + bmv->bmv_length;
 
 
 
 
 
 
 
 355
 356	first_bno = bno = XFS_BB_TO_FSBT(mp, bmv->bmv_offset);
 357	len = XFS_BB_TO_FSB(mp, bmv->bmv_length);
 
 
 
 
 
 
 
 
 
 
 358
 359	error = xfs_iread_extents(NULL, ip, whichfork);
 360	if (error)
 361		goto out_unlock_ilock;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 362
 363	if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) {
 364		/*
 365		 * Report a whole-file hole if the delalloc flag is set to
 366		 * stay compatible with the old implementation.
 367		 */
 368		if (iflags & BMV_IF_DELALLOC)
 369			xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno,
 370					XFS_B_TO_FSB(mp, XFS_ISIZE(ip)));
 371		goto out_unlock_ilock;
 372	}
 373
 374	while (!xfs_getbmap_full(bmv)) {
 375		xfs_trim_extent(&got, first_bno, len);
 
 
 
 
 
 
 
 
 376
 377		/*
 378		 * Report an entry for a hole if this extent doesn't directly
 379		 * follow the previous one.
 380		 */
 381		if (got.br_startoff > bno) {
 382			xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno,
 383					got.br_startoff);
 384			if (xfs_getbmap_full(bmv))
 385				break;
 386		}
 
 
 
 
 
 
 
 
 387
 388		/*
 389		 * In order to report shared extents accurately, we report each
 390		 * distinct shared / unshared part of a single bmbt record with
 391		 * an individual getbmapx record.
 392		 */
 393		bno = got.br_startoff + got.br_blockcount;
 394		rec = got;
 395		do {
 396			error = xfs_getbmap_report_one(ip, bmv, out, bmv_end,
 397					&rec);
 398			if (error || xfs_getbmap_full(bmv))
 399				goto out_unlock_ilock;
 400		} while (xfs_getbmap_next_rec(&rec, bno));
 401
 402		if (!xfs_iext_next_extent(ifp, &icur, &got)) {
 403			xfs_fileoff_t	end = XFS_B_TO_FSB(mp, XFS_ISIZE(ip));
 404
 405			if (bmv->bmv_entries > 0)
 406				out[bmv->bmv_entries - 1].bmv_oflags |=
 407								BMV_OF_LAST;
 408
 409			if (whichfork != XFS_ATTR_FORK && bno < end &&
 410			    !xfs_getbmap_full(bmv)) {
 411				xfs_getbmap_report_hole(ip, bmv, out, bmv_end,
 412						bno, end);
 413			}
 414			break;
 415		}
 416
 417		if (bno >= first_bno + len)
 
 
 418			break;
 419	}
 420
 421out_unlock_ilock:
 422	xfs_iunlock(ip, lock);
 423out_unlock_iolock:
 424	xfs_iunlock(ip, XFS_IOLOCK_SHARED);
 425	return error;
 426}
 427
 428/*
 429 * Dead simple method of punching delalyed allocation blocks from a range in
 430 * the inode.  This will always punch out both the start and end blocks, even
 431 * if the ranges only partially overlap them, so it is up to the caller to
 432 * ensure that partial blocks are not passed in.
 
 
 433 */
 434void
 435xfs_bmap_punch_delalloc_range(
 436	struct xfs_inode	*ip,
 437	int			whichfork,
 438	xfs_off_t		start_byte,
 439	xfs_off_t		end_byte)
 440{
 441	struct xfs_mount	*mp = ip->i_mount;
 442	struct xfs_ifork	*ifp = xfs_ifork_ptr(ip, whichfork);
 443	xfs_fileoff_t		start_fsb = XFS_B_TO_FSBT(mp, start_byte);
 444	xfs_fileoff_t		end_fsb = XFS_B_TO_FSB(mp, end_byte);
 445	struct xfs_bmbt_irec	got, del;
 446	struct xfs_iext_cursor	icur;
 447
 448	ASSERT(!xfs_need_iread_extents(ifp));
 449
 450	xfs_ilock(ip, XFS_ILOCK_EXCL);
 451	if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got))
 452		goto out_unlock;
 
 
 
 453
 454	while (got.br_startoff + got.br_blockcount > start_fsb) {
 455		del = got;
 456		xfs_trim_extent(&del, start_fsb, end_fsb - start_fsb);
 
 
 
 
 
 457
 458		/*
 459		 * A delete can push the cursor forward. Step back to the
 460		 * previous extent on non-delalloc or extents outside the
 461		 * target range.
 462		 */
 463		if (!del.br_blockcount ||
 464		    !isnullstartblock(del.br_startblock)) {
 465			if (!xfs_iext_prev_extent(ifp, &icur, &got))
 466				break;
 467			continue;
 
 
 
 
 
 
 468		}
 
 469
 470		xfs_bmap_del_extent_delay(ip, whichfork, &icur, &got, &del);
 471		if (!xfs_iext_get_extent(ifp, &icur, &got))
 
 
 
 
 
 
 
 
 472			break;
 473	}
 474
 475	if (whichfork == XFS_COW_FORK && !ifp->if_bytes)
 476		xfs_inode_clear_cowblocks_tag(ip);
 
 
 
 477
 478out_unlock:
 479	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 480}
 481
 482/*
 483 * Test whether it is appropriate to check an inode for and free post EOF
 484 * blocks.
 
 485 */
 486bool
 487xfs_can_free_eofblocks(
 488	struct xfs_inode	*ip)
 489{
 490	struct xfs_mount	*mp = ip->i_mount;
 491	bool			found_blocks = false;
 492	xfs_fileoff_t		end_fsb;
 493	xfs_fileoff_t		last_fsb;
 494	struct xfs_bmbt_irec	imap;
 495	struct xfs_iext_cursor	icur;
 496
 497	/*
 498	 * Caller must either hold the exclusive io lock; or be inactivating
 499	 * the inode, which guarantees there are no other users of the inode.
 500	 */
 501	if (!(VFS_I(ip)->i_state & I_FREEING))
 502		xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL);
 503
 504	/* prealloc/delalloc exists only on regular files */
 505	if (!S_ISREG(VFS_I(ip)->i_mode))
 506		return false;
 507
 508	/*
 509	 * Zero sized files with no cached pages and delalloc blocks will not
 510	 * have speculative prealloc/delalloc blocks to remove.
 511	 */
 512	if (VFS_I(ip)->i_size == 0 &&
 513	    VFS_I(ip)->i_mapping->nrpages == 0 &&
 514	    ip->i_delayed_blks == 0)
 515		return false;
 516
 517	/* If we haven't read in the extent list, then don't do it now. */
 518	if (xfs_need_iread_extents(&ip->i_df))
 519		return false;
 520
 521	/*
 522	 * Do not free real extents in preallocated files unless the file has
 523	 * delalloc blocks and we are forced to remove them.
 524	 */
 525	if ((ip->i_diflags & XFS_DIFLAG_PREALLOC) && !ip->i_delayed_blks)
 526		return false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 527
 528	/*
 529	 * Do not try to free post-EOF blocks if EOF is beyond the end of the
 530	 * range supported by the page cache, because the truncation will loop
 531	 * forever.
 532	 */
 533	end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip));
 534	if (xfs_inode_has_bigrtalloc(ip))
 535		end_fsb = xfs_fileoff_roundup_rtx(mp, end_fsb);
 536	last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
 537	if (last_fsb <= end_fsb)
 538		return false;
 
 539
 540	/*
 541	 * Check if there is an post-EOF extent to free.  If there are any
 542	 * delalloc blocks attached to the inode (data fork delalloc
 543	 * reservations or CoW extents of any kind), we need to free them so
 544	 * that inactivation doesn't fail to erase them.
 545	 */
 546	xfs_ilock(ip, XFS_ILOCK_SHARED);
 547	if (ip->i_delayed_blks ||
 548	    xfs_iext_lookup_extent(ip, &ip->i_df, end_fsb, &icur, &imap))
 549		found_blocks = true;
 550	xfs_iunlock(ip, XFS_ILOCK_SHARED);
 551	return found_blocks;
 552}
 553
 554/*
 555 * This is called to free any blocks beyond eof. The caller must hold
 556 * IOLOCK_EXCL unless we are in the inode reclaim path and have the only
 557 * reference to the inode.
 558 */
 559int
 560xfs_free_eofblocks(
 561	struct xfs_inode	*ip)
 562{
 563	struct xfs_trans	*tp;
 564	struct xfs_mount	*mp = ip->i_mount;
 565	int			error;
 566
 567	/* Attach the dquots to the inode up front. */
 568	error = xfs_qm_dqattach(ip);
 569	if (error)
 570		return error;
 
 
 571
 572	/* Wait on dio to ensure i_size has settled. */
 573	inode_dio_wait(VFS_I(ip));
 
 
 
 
 574
 575	/*
 576	 * For preallocated files only free delayed allocations.
 577	 *
 578	 * Note that this means we also leave speculative preallocations in
 579	 * place for preallocated files.
 580	 */
 581	if (ip->i_diflags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) {
 582		if (ip->i_delayed_blks) {
 583			xfs_bmap_punch_delalloc_range(ip, XFS_DATA_FORK,
 584				round_up(XFS_ISIZE(ip), mp->m_sb.sb_blocksize),
 585				LLONG_MAX);
 586		}
 587		xfs_inode_clear_eofblocks_tag(ip);
 588		return 0;
 589	}
 590
 591	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
 592	if (error) {
 593		ASSERT(xfs_is_shutdown(mp));
 594		return error;
 595	}
 596
 597	xfs_ilock(ip, XFS_ILOCK_EXCL);
 598	xfs_trans_ijoin(tp, ip, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 599
 600	/*
 601	 * Do not update the on-disk file size.  If we update the on-disk file
 602	 * size and then the system crashes before the contents of the file are
 603	 * flushed to disk then the files may be full of holes (ie NULL files
 604	 * bug).
 605	 */
 606	error = xfs_itruncate_extents_flags(&tp, ip, XFS_DATA_FORK,
 607				XFS_ISIZE(ip), XFS_BMAPI_NODISCARD);
 608	if (error)
 609		goto err_cancel;
 610
 611	error = xfs_trans_commit(tp);
 612	if (error)
 613		goto out_unlock;
 614
 615	xfs_inode_clear_eofblocks_tag(ip);
 616	goto out_unlock;
 617
 618err_cancel:
 619	/*
 620	 * If we get an error at this point we simply don't
 621	 * bother truncating the file.
 622	 */
 623	xfs_trans_cancel(tp);
 624out_unlock:
 625	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 626	return error;
 627}
 628
 629int
 630xfs_alloc_file_space(
 631	struct xfs_inode	*ip,
 632	xfs_off_t		offset,
 633	xfs_off_t		len)
 
 634{
 635	xfs_mount_t		*mp = ip->i_mount;
 636	xfs_off_t		count;
 
 637	xfs_filblks_t		allocatesize_fsb;
 638	xfs_extlen_t		extsz, temp;
 639	xfs_fileoff_t		startoffset_fsb;
 640	xfs_fileoff_t		endoffset_fsb;
 
 
 641	int			rt;
 642	xfs_trans_t		*tp;
 643	xfs_bmbt_irec_t		imaps[1], *imapp;
 
 
 
 644	int			error;
 645
 646	if (xfs_is_always_cow_inode(ip))
 647		return 0;
 648
 649	trace_xfs_alloc_file_space(ip);
 650
 651	if (xfs_is_shutdown(mp))
 652		return -EIO;
 653
 654	error = xfs_qm_dqattach(ip);
 655	if (error)
 656		return error;
 657
 658	if (len <= 0)
 659		return -EINVAL;
 660
 661	rt = XFS_IS_REALTIME_INODE(ip);
 662	extsz = xfs_get_extsz_hint(ip);
 663
 664	count = len;
 665	imapp = &imaps[0];
 
 666	startoffset_fsb	= XFS_B_TO_FSBT(mp, offset);
 667	endoffset_fsb = XFS_B_TO_FSB(mp, offset + count);
 668	allocatesize_fsb = endoffset_fsb - startoffset_fsb;
 669
 670	/*
 671	 * Allocate file space until done or until there is an error
 672	 */
 673	while (allocatesize_fsb && !error) {
 674		xfs_fileoff_t	s, e;
 675		unsigned int	dblocks, rblocks, resblks;
 676		int		nimaps = 1;
 677
 678		/*
 679		 * Determine space reservations for data/realtime.
 680		 */
 681		if (unlikely(extsz)) {
 682			s = startoffset_fsb;
 683			do_div(s, extsz);
 684			s *= extsz;
 685			e = startoffset_fsb + allocatesize_fsb;
 686			div_u64_rem(startoffset_fsb, extsz, &temp);
 687			if (temp)
 688				e += temp;
 689			div_u64_rem(e, extsz, &temp);
 690			if (temp)
 691				e += extsz - temp;
 692		} else {
 693			s = 0;
 694			e = allocatesize_fsb;
 695		}
 696
 697		/*
 698		 * The transaction reservation is limited to a 32-bit block
 699		 * count, hence we need to limit the number of blocks we are
 700		 * trying to reserve to avoid an overflow. We can't allocate
 701		 * more than @nimaps extents, and an extent is limited on disk
 702		 * to XFS_BMBT_MAX_EXTLEN (21 bits), so use that to enforce the
 703		 * limit.
 704		 */
 705		resblks = min_t(xfs_fileoff_t, (e - s),
 706				(XFS_MAX_BMBT_EXTLEN * nimaps));
 707		if (unlikely(rt)) {
 708			dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
 709			rblocks = resblks;
 
 
 710		} else {
 711			dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks);
 712			rblocks = 0;
 
 713		}
 714
 715		error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write,
 716				dblocks, rblocks, false, &tp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 717		if (error)
 718			break;
 
 
 719
 720		error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK,
 721				XFS_IEXT_ADD_NOSPLIT_CNT);
 722		if (error)
 723			goto error;
 
 
 
 724
 725		/*
 726		 * If the allocator cannot find a single free extent large
 727		 * enough to cover the start block of the requested range,
 728		 * xfs_bmapi_write will return -ENOSR.
 729		 *
 730		 * In that case we simply need to keep looping with the same
 731		 * startoffset_fsb so that one of the following allocations
 732		 * will eventually reach the requested range.
 733		 */
 734		error = xfs_bmapi_write(tp, ip, startoffset_fsb,
 735				allocatesize_fsb, XFS_BMAPI_PREALLOC, 0, imapp,
 736				&nimaps);
 
 
 
 
 737		if (error) {
 738			if (error != -ENOSR)
 739				goto error;
 740			error = 0;
 741		} else {
 742			startoffset_fsb += imapp->br_blockcount;
 743			allocatesize_fsb -= imapp->br_blockcount;
 744		}
 745
 746		ip->i_diflags |= XFS_DIFLAG_PREALLOC;
 747		xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 748
 749		error = xfs_trans_commit(tp);
 750		xfs_iunlock(ip, XFS_ILOCK_EXCL);
 
 
 
 
 
 751	}
 752
 753	return error;
 754
 755error:
 756	xfs_trans_cancel(tp);
 
 
 
 
 757	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 758	return error;
 759}
 760
 761static int
 762xfs_unmap_extent(
 763	struct xfs_inode	*ip,
 764	xfs_fileoff_t		startoffset_fsb,
 765	xfs_filblks_t		len_fsb,
 766	int			*done)
 767{
 768	struct xfs_mount	*mp = ip->i_mount;
 769	struct xfs_trans	*tp;
 770	uint			resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
 771	int			error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 772
 773	error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0,
 774			false, &tp);
 775	if (error)
 776		return error;
 
 777
 778	error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK,
 779			XFS_IEXT_PUNCH_HOLE_CNT);
 780	if (error)
 781		goto out_trans_cancel;
 782
 783	error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, done);
 784	if (error)
 785		goto out_trans_cancel;
 786
 787	error = xfs_trans_commit(tp);
 788out_unlock:
 789	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 790	return error;
 791
 792out_trans_cancel:
 793	xfs_trans_cancel(tp);
 794	goto out_unlock;
 795}
 796
 797/* Caller must first wait for the completion of any pending DIOs if required. */
 798int
 799xfs_flush_unmap_range(
 800	struct xfs_inode	*ip,
 801	xfs_off_t		offset,
 802	xfs_off_t		len)
 803{
 804	struct inode		*inode = VFS_I(ip);
 805	xfs_off_t		rounding, start, end;
 806	int			error;
 
 
 
 
 
 
 807
 808	/*
 809	 * Make sure we extend the flush out to extent alignment
 810	 * boundaries so any extent range overlapping the start/end
 811	 * of the modification we are about to do is clean and idle.
 812	 */
 813	rounding = max_t(xfs_off_t, xfs_inode_alloc_unitsize(ip), PAGE_SIZE);
 814	start = rounddown_64(offset, rounding);
 815	end = roundup_64(offset + len, rounding) - 1;
 
 
 
 
 
 
 
 
 
 816
 817	error = filemap_write_and_wait_range(inode->i_mapping, start, end);
 818	if (error)
 819		return error;
 820	truncate_pagecache_range(inode, start, end);
 821	return 0;
 
 
 
 
 
 
 
 
 
 822}
 823
 824int
 825xfs_free_file_space(
 826	struct xfs_inode	*ip,
 827	xfs_off_t		offset,
 828	xfs_off_t		len)
 829{
 830	struct xfs_mount	*mp = ip->i_mount;
 
 
 
 
 
 
 
 
 
 
 
 
 
 831	xfs_fileoff_t		startoffset_fsb;
 832	xfs_fileoff_t		endoffset_fsb;
 833	int			done = 0, error;
 
 834
 835	trace_xfs_free_file_space(ip);
 836
 837	error = xfs_qm_dqattach(ip);
 838	if (error)
 839		return error;
 840
 
 841	if (len <= 0)	/* if nothing being freed */
 842		return 0;
 843
 844	/*
 845	 * Now AIO and DIO has drained we flush and (if necessary) invalidate
 846	 * the cached range over the first operation we are about to run.
 847	 */
 848	error = xfs_flush_unmap_range(ip, offset, len);
 849	if (error)
 850		return error;
 
 
 
 851
 852	startoffset_fsb = XFS_B_TO_FSB(mp, offset);
 853	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
 854
 855	/* We can only free complete realtime extents. */
 856	if (xfs_inode_has_bigrtalloc(ip)) {
 857		startoffset_fsb = xfs_fileoff_roundup_rtx(mp, startoffset_fsb);
 858		endoffset_fsb = xfs_fileoff_rounddown_rtx(mp, endoffset_fsb);
 859	}
 
 
 860
 861	/*
 862	 * Need to zero the stuff we're not freeing, on disk.
 863	 */
 864	if (endoffset_fsb > startoffset_fsb) {
 865		while (!done) {
 866			error = xfs_unmap_extent(ip, startoffset_fsb,
 867					endoffset_fsb - startoffset_fsb, &done);
 868			if (error)
 869				return error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 870		}
 871	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 872
 873	/*
 874	 * Now that we've unmap all full blocks we'll have to zero out any
 875	 * partial block at the beginning and/or end.  xfs_zero_range is smart
 876	 * enough to skip any holes, including those we just created, but we
 877	 * must take care not to zero beyond EOF and enlarge i_size.
 878	 */
 879	if (offset >= XFS_ISIZE(ip))
 880		return 0;
 881	if (offset + len > XFS_ISIZE(ip))
 882		len = XFS_ISIZE(ip) - offset;
 883	error = xfs_zero_range(ip, offset, len, NULL);
 884	if (error)
 885		return error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 886
 887	/*
 888	 * If we zeroed right up to EOF and EOF straddles a page boundary we
 889	 * must make sure that the post-EOF area is also zeroed because the
 890	 * page could be mmap'd and xfs_zero_range doesn't do that for us.
 891	 * Writeback of the eof page will do this, albeit clumsily.
 892	 */
 893	if (offset + len >= XFS_ISIZE(ip) && offset_in_page(offset + len) > 0) {
 894		error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
 895				round_down(offset + len, PAGE_SIZE), LLONG_MAX);
 896	}
 897
 
 898	return error;
 
 
 
 
 
 
 
 899}
 900
 901static int
 902xfs_prepare_shift(
 
 903	struct xfs_inode	*ip,
 904	loff_t			offset)
 
 905{
 906	unsigned int		rounding;
 
 
 
 907	int			error;
 908
 
 
 
 
 909	/*
 910	 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation
 911	 * into the accessible region of the file.
 
 912	 */
 913	if (xfs_can_free_eofblocks(ip)) {
 914		error = xfs_free_eofblocks(ip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 915		if (error)
 916			return error;
 917	}
 918
 919	/*
 920	 * Shift operations must stabilize the start block offset boundary along
 921	 * with the full range of the operation. If we don't, a COW writeback
 922	 * completion could race with an insert, front merge with the start
 923	 * extent (after split) during the shift and corrupt the file. Start
 924	 * with the allocation unit just prior to the start to stabilize the
 925	 * boundary.
 926	 */
 927	rounding = xfs_inode_alloc_unitsize(ip);
 928	offset = rounddown_64(offset, rounding);
 929	if (offset)
 930		offset -= rounding;
 931
 932	/*
 933	 * Writeback and invalidate cache for the remainder of the file as we're
 934	 * about to shift down every extent from offset to EOF.
 935	 */
 936	error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip));
 937	if (error)
 938		return error;
 939
 940	/*
 941	 * Clean out anything hanging around in the cow fork now that
 942	 * we've flushed all the dirty data out to disk to avoid having
 943	 * CoW extents at the wrong offsets.
 944	 */
 945	if (xfs_inode_has_cow_data(ip)) {
 946		error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF,
 947				true);
 948		if (error)
 949			return error;
 950	}
 951
 952	return 0;
 
 
 953}
 954
 955/*
 956 * xfs_collapse_file_space()
 957 *	This routine frees disk space and shift extent for the given file.
 958 *	The first thing we do is to free data blocks in the specified range
 959 *	by calling xfs_free_file_space(). It would also sync dirty data
 960 *	and invalidate page cache over the region on which collapse range
 961 *	is working. And Shift extent records to the left to cover a hole.
 962 * RETURNS:
 963 *	0 on success
 964 *	errno on error
 965 *
 966 */
 967int
 968xfs_collapse_file_space(
 969	struct xfs_inode	*ip,
 970	xfs_off_t		offset,
 971	xfs_off_t		len)
 972{
 
 973	struct xfs_mount	*mp = ip->i_mount;
 974	struct xfs_trans	*tp;
 975	int			error;
 976	xfs_fileoff_t		next_fsb = XFS_B_TO_FSB(mp, offset + len);
 977	xfs_fileoff_t		shift_fsb = XFS_B_TO_FSB(mp, len);
 978	bool			done = false;
 
 
 
 979
 980	xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL);
 981
 982	trace_xfs_collapse_file_space(ip);
 983
 
 
 
 984	error = xfs_free_file_space(ip, offset, len);
 985	if (error)
 986		return error;
 987
 988	error = xfs_prepare_shift(ip, offset);
 989	if (error)
 990		return error;
 991
 992	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp);
 993	if (error)
 994		return error;
 995
 996	xfs_ilock(ip, XFS_ILOCK_EXCL);
 997	xfs_trans_ijoin(tp, ip, 0);
 998
 999	while (!done) {
1000		error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb,
1001				&done);
1002		if (error)
1003			goto out_trans_cancel;
1004		if (done)
1005			break;
 
1006
1007		/* finish any deferred frees and roll the transaction */
1008		error = xfs_defer_finish(&tp);
 
 
 
1009		if (error)
1010			goto out_trans_cancel;
1011	}
1012
1013	error = xfs_trans_commit(tp);
1014	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1015	return error;
1016
1017out_trans_cancel:
1018	xfs_trans_cancel(tp);
1019	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1020	return error;
1021}
1022
1023/*
1024 * xfs_insert_file_space()
1025 *	This routine create hole space by shifting extents for the given file.
1026 *	The first thing we do is to sync dirty data and invalidate page cache
1027 *	over the region on which insert range is working. And split an extent
1028 *	to two extents at given offset by calling xfs_bmap_split_extent.
1029 *	And shift all extent records which are laying between [offset,
1030 *	last allocated extent] to the right to reserve hole range.
1031 * RETURNS:
1032 *	0 on success
1033 *	errno on error
1034 */
1035int
1036xfs_insert_file_space(
1037	struct xfs_inode	*ip,
1038	loff_t			offset,
1039	loff_t			len)
1040{
1041	struct xfs_mount	*mp = ip->i_mount;
1042	struct xfs_trans	*tp;
1043	int			error;
1044	xfs_fileoff_t		stop_fsb = XFS_B_TO_FSB(mp, offset);
1045	xfs_fileoff_t		next_fsb = NULLFSBLOCK;
1046	xfs_fileoff_t		shift_fsb = XFS_B_TO_FSB(mp, len);
1047	bool			done = false;
1048
1049	xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL);
1050
1051	trace_xfs_insert_file_space(ip);
1052
1053	error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb);
1054	if (error)
1055		return error;
1056
1057	error = xfs_prepare_shift(ip, offset);
1058	if (error)
1059		return error;
1060
1061	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write,
1062			XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp);
1063	if (error)
1064		return error;
1065
1066	xfs_ilock(ip, XFS_ILOCK_EXCL);
1067	xfs_trans_ijoin(tp, ip, 0);
1068
1069	error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK,
1070			XFS_IEXT_PUNCH_HOLE_CNT);
1071	if (error)
1072		goto out_trans_cancel;
1073
1074	/*
1075	 * The extent shifting code works on extent granularity. So, if stop_fsb
1076	 * is not the starting block of extent, we need to split the extent at
1077	 * stop_fsb.
1078	 */
1079	error = xfs_bmap_split_extent(tp, ip, stop_fsb);
1080	if (error)
1081		goto out_trans_cancel;
1082
1083	do {
1084		error = xfs_defer_finish(&tp);
1085		if (error)
1086			goto out_trans_cancel;
1087
1088		error = xfs_bmap_insert_extents(tp, ip, &next_fsb, shift_fsb,
1089				&done, stop_fsb);
1090		if (error)
1091			goto out_trans_cancel;
1092	} while (!done);
1093
1094	error = xfs_trans_commit(tp);
1095	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1096	return error;
1097
1098out_trans_cancel:
1099	xfs_trans_cancel(tp);
1100	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1101	return error;
1102}
1103
1104/*
1105 * We need to check that the format of the data fork in the temporary inode is
1106 * valid for the target inode before doing the swap. This is not a problem with
1107 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized
1108 * data fork depending on the space the attribute fork is taking so we can get
1109 * invalid formats on the target inode.
1110 *
1111 * E.g. target has space for 7 extents in extent format, temp inode only has
1112 * space for 6.  If we defragment down to 7 extents, then the tmp format is a
1113 * btree, but when swapped it needs to be in extent format. Hence we can't just
1114 * blindly swap data forks on attr2 filesystems.
1115 *
1116 * Note that we check the swap in both directions so that we don't end up with
1117 * a corrupt temporary inode, either.
1118 *
1119 * Note that fixing the way xfs_fsr sets up the attribute fork in the source
1120 * inode will prevent this situation from occurring, so all we do here is
1121 * reject and log the attempt. basically we are putting the responsibility on
1122 * userspace to get this right.
1123 */
1124static int
1125xfs_swap_extents_check_format(
1126	struct xfs_inode	*ip,	/* target inode */
1127	struct xfs_inode	*tip)	/* tmp inode */
1128{
1129	struct xfs_ifork	*ifp = &ip->i_df;
1130	struct xfs_ifork	*tifp = &tip->i_df;
1131
1132	/* User/group/project quota ids must match if quotas are enforced. */
1133	if (XFS_IS_QUOTA_ON(ip->i_mount) &&
1134	    (!uid_eq(VFS_I(ip)->i_uid, VFS_I(tip)->i_uid) ||
1135	     !gid_eq(VFS_I(ip)->i_gid, VFS_I(tip)->i_gid) ||
1136	     ip->i_projid != tip->i_projid))
1137		return -EINVAL;
1138
1139	/* Should never get a local format */
1140	if (ifp->if_format == XFS_DINODE_FMT_LOCAL ||
1141	    tifp->if_format == XFS_DINODE_FMT_LOCAL)
1142		return -EINVAL;
1143
1144	/*
1145	 * if the target inode has less extents that then temporary inode then
1146	 * why did userspace call us?
1147	 */
1148	if (ifp->if_nextents < tifp->if_nextents)
1149		return -EINVAL;
1150
1151	/*
1152	 * If we have to use the (expensive) rmap swap method, we can
1153	 * handle any number of extents and any format.
1154	 */
1155	if (xfs_has_rmapbt(ip->i_mount))
1156		return 0;
1157
1158	/*
1159	 * if the target inode is in extent form and the temp inode is in btree
1160	 * form then we will end up with the target inode in the wrong format
1161	 * as we already know there are less extents in the temp inode.
1162	 */
1163	if (ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
1164	    tifp->if_format == XFS_DINODE_FMT_BTREE)
1165		return -EINVAL;
1166
1167	/* Check temp in extent form to max in target */
1168	if (tifp->if_format == XFS_DINODE_FMT_EXTENTS &&
1169	    tifp->if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1170		return -EINVAL;
 
1171
1172	/* Check target in extent form to max in temp */
1173	if (ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
1174	    ifp->if_nextents > XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1175		return -EINVAL;
 
1176
1177	/*
1178	 * If we are in a btree format, check that the temp root block will fit
1179	 * in the target and that it has enough extents to be in btree format
1180	 * in the target.
1181	 *
1182	 * Note that we have to be careful to allow btree->extent conversions
1183	 * (a common defrag case) which will occur when the temp inode is in
1184	 * extent format...
1185	 */
1186	if (tifp->if_format == XFS_DINODE_FMT_BTREE) {
1187		if (xfs_inode_has_attr_fork(ip) &&
1188		    xfs_bmap_bmdr_space(tifp->if_broot) > xfs_inode_fork_boff(ip))
1189			return -EINVAL;
1190		if (tifp->if_nextents <= XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1191			return -EINVAL;
 
1192	}
1193
1194	/* Reciprocal target->temp btree format checks */
1195	if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
1196		if (xfs_inode_has_attr_fork(tip) &&
1197		    xfs_bmap_bmdr_space(ip->i_df.if_broot) > xfs_inode_fork_boff(tip))
1198			return -EINVAL;
1199		if (ifp->if_nextents <= XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1200			return -EINVAL;
 
1201	}
1202
1203	return 0;
1204}
1205
1206static int
1207xfs_swap_extent_flush(
1208	struct xfs_inode	*ip)
1209{
1210	int	error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1211
1212	error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
1213	if (error)
1214		return error;
1215	truncate_pagecache_range(VFS_I(ip), 0, -1);
 
 
 
 
1216
1217	/* Verify O_DIRECT for ftmp */
1218	if (VFS_I(ip)->i_mapping->nrpages)
1219		return -EINVAL;
1220	return 0;
1221}
1222
1223/*
1224 * Move extents from one file to another, when rmap is enabled.
1225 */
1226STATIC int
1227xfs_swap_extent_rmap(
1228	struct xfs_trans		**tpp,
1229	struct xfs_inode		*ip,
1230	struct xfs_inode		*tip)
1231{
1232	struct xfs_trans		*tp = *tpp;
1233	struct xfs_bmbt_irec		irec;
1234	struct xfs_bmbt_irec		uirec;
1235	struct xfs_bmbt_irec		tirec;
1236	xfs_fileoff_t			offset_fsb;
1237	xfs_fileoff_t			end_fsb;
1238	xfs_filblks_t			count_fsb;
1239	int				error;
1240	xfs_filblks_t			ilen;
1241	xfs_filblks_t			rlen;
1242	int				nimaps;
1243	uint64_t			tip_flags2;
1244
1245	/*
1246	 * If the source file has shared blocks, we must flag the donor
1247	 * file as having shared blocks so that we get the shared-block
1248	 * rmap functions when we go to fix up the rmaps.  The flags
1249	 * will be switch for reals later.
1250	 */
1251	tip_flags2 = tip->i_diflags2;
1252	if (ip->i_diflags2 & XFS_DIFLAG2_REFLINK)
1253		tip->i_diflags2 |= XFS_DIFLAG2_REFLINK;
1254
1255	offset_fsb = 0;
1256	end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip)));
1257	count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb);
1258
1259	while (count_fsb) {
1260		/* Read extent from the donor file */
1261		nimaps = 1;
1262		error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec,
1263				&nimaps, 0);
1264		if (error)
1265			goto out;
1266		ASSERT(nimaps == 1);
1267		ASSERT(tirec.br_startblock != DELAYSTARTBLOCK);
1268
1269		trace_xfs_swap_extent_rmap_remap(tip, &tirec);
1270		ilen = tirec.br_blockcount;
 
 
1271
1272		/* Unmap the old blocks in the source file. */
1273		while (tirec.br_blockcount) {
1274			ASSERT(tp->t_highest_agno == NULLAGNUMBER);
1275			trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec);
1276
1277			/* Read extent from the source file */
1278			nimaps = 1;
1279			error = xfs_bmapi_read(ip, tirec.br_startoff,
1280					tirec.br_blockcount, &irec,
1281					&nimaps, 0);
1282			if (error)
1283				goto out;
1284			ASSERT(nimaps == 1);
1285			ASSERT(tirec.br_startoff == irec.br_startoff);
1286			trace_xfs_swap_extent_rmap_remap_piece(ip, &irec);
1287
1288			/* Trim the extent. */
1289			uirec = tirec;
1290			uirec.br_blockcount = rlen = min_t(xfs_filblks_t,
1291					tirec.br_blockcount,
1292					irec.br_blockcount);
1293			trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec);
1294
1295			if (xfs_bmap_is_real_extent(&uirec)) {
1296				error = xfs_iext_count_extend(tp, ip,
1297						XFS_DATA_FORK,
1298						XFS_IEXT_SWAP_RMAP_CNT);
1299				if (error)
1300					goto out;
1301			}
1302
1303			if (xfs_bmap_is_real_extent(&irec)) {
1304				error = xfs_iext_count_extend(tp, tip,
1305						XFS_DATA_FORK,
1306						XFS_IEXT_SWAP_RMAP_CNT);
1307				if (error)
1308					goto out;
1309			}
1310
1311			/* Remove the mapping from the donor file. */
1312			xfs_bmap_unmap_extent(tp, tip, XFS_DATA_FORK, &uirec);
1313
1314			/* Remove the mapping from the source file. */
1315			xfs_bmap_unmap_extent(tp, ip, XFS_DATA_FORK, &irec);
 
 
 
 
 
 
1316
1317			/* Map the donor file's blocks into the source file. */
1318			xfs_bmap_map_extent(tp, ip, XFS_DATA_FORK, &uirec);
 
 
 
 
 
 
 
 
 
 
 
 
1319
1320			/* Map the source file's blocks into the donor file. */
1321			xfs_bmap_map_extent(tp, tip, XFS_DATA_FORK, &irec);
 
 
 
 
 
 
 
 
1322
1323			error = xfs_defer_finish(tpp);
1324			tp = *tpp;
1325			if (error)
1326				goto out;
1327
1328			tirec.br_startoff += rlen;
1329			if (tirec.br_startblock != HOLESTARTBLOCK &&
1330			    tirec.br_startblock != DELAYSTARTBLOCK)
1331				tirec.br_startblock += rlen;
1332			tirec.br_blockcount -= rlen;
1333		}
 
 
1334
1335		/* Roll on... */
1336		count_fsb -= ilen;
1337		offset_fsb += ilen;
 
 
 
 
1338	}
1339
1340	tip->i_diflags2 = tip_flags2;
1341	return 0;
1342
1343out:
1344	trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_);
1345	tip->i_diflags2 = tip_flags2;
1346	return error;
1347}
1348
1349/* Swap the extents of two files by swapping data forks. */
1350STATIC int
1351xfs_swap_extent_forks(
1352	struct xfs_trans	*tp,
1353	struct xfs_inode	*ip,
1354	struct xfs_inode	*tip,
1355	int			*src_log_flags,
1356	int			*target_log_flags)
1357{
1358	xfs_filblks_t		aforkblks = 0;
1359	xfs_filblks_t		taforkblks = 0;
1360	xfs_extnum_t		junk;
1361	uint64_t		tmp;
1362	int			error;
1363
1364	/*
1365	 * Count the number of extended attribute blocks
1366	 */
1367	if (xfs_inode_has_attr_fork(ip) && ip->i_af.if_nextents > 0 &&
1368	    ip->i_af.if_format != XFS_DINODE_FMT_LOCAL) {
1369		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk,
1370				&aforkblks);
1371		if (error)
1372			return error;
1373	}
1374	if (xfs_inode_has_attr_fork(tip) && tip->i_af.if_nextents > 0 &&
1375	    tip->i_af.if_format != XFS_DINODE_FMT_LOCAL) {
1376		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk,
1377				&taforkblks);
1378		if (error)
1379			return error;
1380	}
1381
 
 
 
1382	/*
1383	 * Btree format (v3) inodes have the inode number stamped in the bmbt
1384	 * block headers. We can't start changing the bmbt blocks until the
1385	 * inode owner change is logged so recovery does the right thing in the
1386	 * event of a crash. Set the owner change log flags now and leave the
1387	 * bmbt scan as the last step.
1388	 */
1389	if (xfs_has_v3inodes(ip->i_mount)) {
1390		if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE)
1391			(*target_log_flags) |= XFS_ILOG_DOWNER;
1392		if (tip->i_df.if_format == XFS_DINODE_FMT_BTREE)
1393			(*src_log_flags) |= XFS_ILOG_DOWNER;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1394	}
1395
1396	/*
1397	 * Swap the data forks of the inodes
1398	 */
1399	swap(ip->i_df, tip->i_df);
 
 
 
 
1400
1401	/*
1402	 * Fix the on-disk inode values
1403	 */
1404	tmp = (uint64_t)ip->i_nblocks;
1405	ip->i_nblocks = tip->i_nblocks - taforkblks + aforkblks;
1406	tip->i_nblocks = tmp + taforkblks - aforkblks;
 
 
 
 
 
 
 
 
1407
1408	/*
1409	 * The extents in the source inode could still contain speculative
1410	 * preallocation beyond EOF (e.g. the file is open but not modified
1411	 * while defrag is in progress). In that case, we need to copy over the
1412	 * number of delalloc blocks the data fork in the source inode is
1413	 * tracking beyond EOF so that when the fork is truncated away when the
1414	 * temporary inode is unlinked we don't underrun the i_delayed_blks
1415	 * counter on that inode.
1416	 */
1417	ASSERT(tip->i_delayed_blks == 0);
1418	tip->i_delayed_blks = ip->i_delayed_blks;
1419	ip->i_delayed_blks = 0;
1420
1421	switch (ip->i_df.if_format) {
1422	case XFS_DINODE_FMT_EXTENTS:
1423		(*src_log_flags) |= XFS_ILOG_DEXT;
 
 
 
 
 
 
 
 
1424		break;
1425	case XFS_DINODE_FMT_BTREE:
1426		ASSERT(!xfs_has_v3inodes(ip->i_mount) ||
1427		       (*src_log_flags & XFS_ILOG_DOWNER));
1428		(*src_log_flags) |= XFS_ILOG_DBROOT;
1429		break;
1430	}
1431
1432	switch (tip->i_df.if_format) {
1433	case XFS_DINODE_FMT_EXTENTS:
1434		(*target_log_flags) |= XFS_ILOG_DEXT;
 
 
 
 
 
 
 
 
1435		break;
1436	case XFS_DINODE_FMT_BTREE:
1437		(*target_log_flags) |= XFS_ILOG_DBROOT;
1438		ASSERT(!xfs_has_v3inodes(ip->i_mount) ||
1439		       (*target_log_flags & XFS_ILOG_DOWNER));
1440		break;
1441	}
1442
1443	return 0;
1444}
1445
1446/*
1447 * Fix up the owners of the bmbt blocks to refer to the current inode. The
1448 * change owner scan attempts to order all modified buffers in the current
1449 * transaction. In the event of ordered buffer failure, the offending buffer is
1450 * physically logged as a fallback and the scan returns -EAGAIN. We must roll
1451 * the transaction in this case to replenish the fallback log reservation and
1452 * restart the scan. This process repeats until the scan completes.
1453 */
1454static int
1455xfs_swap_change_owner(
1456	struct xfs_trans	**tpp,
1457	struct xfs_inode	*ip,
1458	struct xfs_inode	*tmpip)
1459{
1460	int			error;
1461	struct xfs_trans	*tp = *tpp;
1462
1463	do {
1464		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino,
1465					      NULL);
1466		/* success or fatal error */
1467		if (error != -EAGAIN)
1468			break;
1469
1470		error = xfs_trans_roll(tpp);
1471		if (error)
1472			break;
1473		tp = *tpp;
1474
1475		/*
1476		 * Redirty both inodes so they can relog and keep the log tail
1477		 * moving forward.
1478		 */
1479		xfs_trans_ijoin(tp, ip, 0);
1480		xfs_trans_ijoin(tp, tmpip, 0);
1481		xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1482		xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE);
1483	} while (true);
1484
1485	return error;
1486}
1487
1488int
1489xfs_swap_extents(
1490	struct xfs_inode	*ip,	/* target inode */
1491	struct xfs_inode	*tip,	/* tmp inode */
1492	struct xfs_swapext	*sxp)
1493{
1494	struct xfs_mount	*mp = ip->i_mount;
1495	struct xfs_trans	*tp;
1496	struct xfs_bstat	*sbp = &sxp->sx_stat;
1497	int			src_log_flags, target_log_flags;
1498	int			error = 0;
1499	uint64_t		f;
1500	int			resblks = 0;
1501	unsigned int		flags = 0;
1502	struct timespec64	ctime, mtime;
1503
1504	/*
1505	 * Lock the inodes against other IO, page faults and truncate to
1506	 * begin with.  Then we can ensure the inodes are flushed and have no
1507	 * page cache safely. Once we have done this we can take the ilocks and
1508	 * do the rest of the checks.
1509	 */
1510	lock_two_nondirectories(VFS_I(ip), VFS_I(tip));
1511	filemap_invalidate_lock_two(VFS_I(ip)->i_mapping,
1512				    VFS_I(tip)->i_mapping);
1513
1514	/* Verify that both files have the same format */
1515	if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) {
1516		error = -EINVAL;
1517		goto out_unlock;
1518	}
1519
1520	/* Verify both files are either real-time or non-realtime */
1521	if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
1522		error = -EINVAL;
1523		goto out_unlock;
1524	}
1525
1526	/*
1527	 * The rmapbt implementation is unable to resume a swapext operation
1528	 * after a crash if the allocation unit size is larger than a block.
1529	 * This (deprecated) interface will not be upgraded to handle this
1530	 * situation.  Defragmentation must be performed with the commit range
1531	 * ioctl.
1532	 */
1533	if (XFS_IS_REALTIME_INODE(ip) && xfs_has_rtgroups(ip->i_mount)) {
1534		error = -EOPNOTSUPP;
1535		goto out_unlock;
1536	}
1537
1538	error = xfs_qm_dqattach(ip);
1539	if (error)
1540		goto out_unlock;
1541
1542	error = xfs_qm_dqattach(tip);
1543	if (error)
1544		goto out_unlock;
1545
1546	error = xfs_swap_extent_flush(ip);
1547	if (error)
1548		goto out_unlock;
1549	error = xfs_swap_extent_flush(tip);
1550	if (error)
1551		goto out_unlock;
1552
1553	if (xfs_inode_has_cow_data(tip)) {
1554		error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true);
1555		if (error)
1556			goto out_unlock;
1557	}
1558
1559	/*
1560	 * Extent "swapping" with rmap requires a permanent reservation and
1561	 * a block reservation because it's really just a remap operation
1562	 * performed with log redo items!
1563	 */
1564	if (xfs_has_rmapbt(mp)) {
1565		int		w = XFS_DATA_FORK;
1566		uint32_t	ipnext = ip->i_df.if_nextents;
1567		uint32_t	tipnext	= tip->i_df.if_nextents;
1568
1569		/*
1570		 * Conceptually this shouldn't affect the shape of either bmbt,
1571		 * but since we atomically move extents one by one, we reserve
1572		 * enough space to rebuild both trees.
1573		 */
1574		resblks = XFS_SWAP_RMAP_SPACE_RES(mp, ipnext, w);
1575		resblks +=  XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w);
1576
1577		/*
1578		 * If either inode straddles a bmapbt block allocation boundary,
1579		 * the rmapbt algorithm triggers repeated allocs and frees as
1580		 * extents are remapped. This can exhaust the block reservation
1581		 * prematurely and cause shutdown. Return freed blocks to the
1582		 * transaction reservation to counter this behavior.
1583		 */
1584		flags |= XFS_TRANS_RES_FDBLKS;
1585	}
1586	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags,
1587				&tp);
1588	if (error)
1589		goto out_unlock;
1590
1591	/*
1592	 * Lock and join the inodes to the tansaction so that transaction commit
1593	 * or cancel will unlock the inodes from this point onwards.
1594	 */
1595	xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL);
1596	xfs_trans_ijoin(tp, ip, 0);
1597	xfs_trans_ijoin(tp, tip, 0);
1598
1599
1600	/* Verify all data are being swapped */
1601	if (sxp->sx_offset != 0 ||
1602	    sxp->sx_length != ip->i_disk_size ||
1603	    sxp->sx_length != tip->i_disk_size) {
1604		error = -EFAULT;
1605		goto out_trans_cancel;
1606	}
1607
1608	trace_xfs_swap_extent_before(ip, 0);
1609	trace_xfs_swap_extent_before(tip, 1);
1610
1611	/* check inode formats now that data is flushed */
1612	error = xfs_swap_extents_check_format(ip, tip);
1613	if (error) {
1614		xfs_notice(mp,
1615		    "%s: inode 0x%llx format is incompatible for exchanging.",
1616				__func__, ip->i_ino);
1617		goto out_trans_cancel;
1618	}
1619
1620	/*
1621	 * Compare the current change & modify times with that
1622	 * passed in.  If they differ, we abort this swap.
1623	 * This is the mechanism used to ensure the calling
1624	 * process that the file was not changed out from
1625	 * under it.
1626	 */
1627	ctime = inode_get_ctime(VFS_I(ip));
1628	mtime = inode_get_mtime(VFS_I(ip));
1629	if ((sbp->bs_ctime.tv_sec != ctime.tv_sec) ||
1630	    (sbp->bs_ctime.tv_nsec != ctime.tv_nsec) ||
1631	    (sbp->bs_mtime.tv_sec != mtime.tv_sec) ||
1632	    (sbp->bs_mtime.tv_nsec != mtime.tv_nsec)) {
1633		error = -EBUSY;
1634		goto out_trans_cancel;
1635	}
1636
1637	/*
1638	 * Note the trickiness in setting the log flags - we set the owner log
1639	 * flag on the opposite inode (i.e. the inode we are setting the new
1640	 * owner to be) because once we swap the forks and log that, log
1641	 * recovery is going to see the fork as owned by the swapped inode,
1642	 * not the pre-swapped inodes.
1643	 */
1644	src_log_flags = XFS_ILOG_CORE;
1645	target_log_flags = XFS_ILOG_CORE;
1646
1647	if (xfs_has_rmapbt(mp))
1648		error = xfs_swap_extent_rmap(&tp, ip, tip);
1649	else
1650		error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags,
1651				&target_log_flags);
1652	if (error)
1653		goto out_trans_cancel;
1654
1655	/* Do we have to swap reflink flags? */
1656	if ((ip->i_diflags2 & XFS_DIFLAG2_REFLINK) ^
1657	    (tip->i_diflags2 & XFS_DIFLAG2_REFLINK)) {
1658		f = ip->i_diflags2 & XFS_DIFLAG2_REFLINK;
1659		ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
1660		ip->i_diflags2 |= tip->i_diflags2 & XFS_DIFLAG2_REFLINK;
1661		tip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
1662		tip->i_diflags2 |= f & XFS_DIFLAG2_REFLINK;
1663	}
1664
1665	/* Swap the cow forks. */
1666	if (xfs_has_reflink(mp)) {
1667		ASSERT(!ip->i_cowfp ||
1668		       ip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS);
1669		ASSERT(!tip->i_cowfp ||
1670		       tip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS);
1671
1672		swap(ip->i_cowfp, tip->i_cowfp);
1673
1674		if (ip->i_cowfp && ip->i_cowfp->if_bytes)
1675			xfs_inode_set_cowblocks_tag(ip);
1676		else
1677			xfs_inode_clear_cowblocks_tag(ip);
1678		if (tip->i_cowfp && tip->i_cowfp->if_bytes)
1679			xfs_inode_set_cowblocks_tag(tip);
1680		else
1681			xfs_inode_clear_cowblocks_tag(tip);
1682	}
1683
1684	xfs_trans_log_inode(tp, ip,  src_log_flags);
1685	xfs_trans_log_inode(tp, tip, target_log_flags);
1686
1687	/*
1688	 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems
1689	 * have inode number owner values in the bmbt blocks that still refer to
1690	 * the old inode. Scan each bmbt to fix up the owner values with the
1691	 * inode number of the current inode.
1692	 */
1693	if (src_log_flags & XFS_ILOG_DOWNER) {
1694		error = xfs_swap_change_owner(&tp, ip, tip);
1695		if (error)
1696			goto out_trans_cancel;
1697	}
1698	if (target_log_flags & XFS_ILOG_DOWNER) {
1699		error = xfs_swap_change_owner(&tp, tip, ip);
1700		if (error)
1701			goto out_trans_cancel;
1702	}
1703
1704	/*
1705	 * If this is a synchronous mount, make sure that the
1706	 * transaction goes to disk before returning to the user.
1707	 */
1708	if (xfs_has_wsync(mp))
1709		xfs_trans_set_sync(tp);
1710
1711	error = xfs_trans_commit(tp);
1712
1713	trace_xfs_swap_extent_after(ip, 0);
1714	trace_xfs_swap_extent_after(tip, 1);
 
 
 
1715
1716out_unlock_ilock:
1717	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1718	xfs_iunlock(tip, XFS_ILOCK_EXCL);
1719out_unlock:
1720	filemap_invalidate_unlock_two(VFS_I(ip)->i_mapping,
1721				      VFS_I(tip)->i_mapping);
1722	unlock_two_nondirectories(VFS_I(ip), VFS_I(tip));
1723	return error;
1724
1725out_trans_cancel:
1726	xfs_trans_cancel(tp);
1727	goto out_unlock_ilock;
1728}