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_mount.h"
  27#include "xfs_da_format.h"
  28#include "xfs_defer.h"
  29#include "xfs_inode.h"
  30#include "xfs_btree.h"
  31#include "xfs_trans.h"
  32#include "xfs_extfree_item.h"
  33#include "xfs_alloc.h"
  34#include "xfs_bmap.h"
  35#include "xfs_bmap_util.h"
  36#include "xfs_bmap_btree.h"
  37#include "xfs_rtalloc.h"
  38#include "xfs_error.h"
  39#include "xfs_quota.h"
  40#include "xfs_trans_space.h"
  41#include "xfs_trace.h"
  42#include "xfs_icache.h"
  43#include "xfs_log.h"
  44#include "xfs_rmap_btree.h"
  45#include "xfs_iomap.h"
  46#include "xfs_reflink.h"
  47#include "xfs_refcount.h"
 
  48
  49/* Kernel only BMAP related definitions and functions */
  50
  51/*
  52 * Convert the given file system block to a disk block.  We have to treat it
  53 * differently based on whether the file is a real time file or not, because the
  54 * bmap code does.
  55 */
  56xfs_daddr_t
  57xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
  58{
  59	return (XFS_IS_REALTIME_INODE(ip) ? \
  60		 (xfs_daddr_t)XFS_FSB_TO_BB((ip)->i_mount, (fsb)) : \
  61		 XFS_FSB_TO_DADDR((ip)->i_mount, (fsb)));
  62}
  63
  64/*
  65 * Routine to zero an extent on disk allocated to the specific inode.
  66 *
  67 * The VFS functions take a linearised filesystem block offset, so we have to
  68 * convert the sparse xfs fsb to the right format first.
  69 * VFS types are real funky, too.
  70 */
  71int
  72xfs_zero_extent(
  73	struct xfs_inode *ip,
  74	xfs_fsblock_t	start_fsb,
  75	xfs_off_t	count_fsb)
  76{
  77	struct xfs_mount *mp = ip->i_mount;
  78	xfs_daddr_t	sector = xfs_fsb_to_db(ip, start_fsb);
  79	sector_t	block = XFS_BB_TO_FSBT(mp, sector);
  80
  81	return blkdev_issue_zeroout(xfs_find_bdev_for_inode(VFS_I(ip)),
  82		block << (mp->m_super->s_blocksize_bits - 9),
  83		count_fsb << (mp->m_super->s_blocksize_bits - 9),
  84		GFP_NOFS, true);
  85}
  86
  87int
  88xfs_bmap_rtalloc(
  89	struct xfs_bmalloca	*ap)	/* bmap alloc argument struct */
  90{
  91	xfs_alloctype_t	atype = 0;	/* type for allocation routines */
  92	int		error;		/* error return value */
  93	xfs_mount_t	*mp;		/* mount point structure */
  94	xfs_extlen_t	prod = 0;	/* product factor for allocators */
  95	xfs_extlen_t	ralen = 0;	/* realtime allocation length */
  96	xfs_extlen_t	align;		/* minimum allocation alignment */
  97	xfs_rtblock_t	rtb;
  98
  99	mp = ap->ip->i_mount;
 100	align = xfs_get_extsz_hint(ap->ip);
 101	prod = align / mp->m_sb.sb_rextsize;
 102	error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
 103					align, 1, ap->eof, 0,
 104					ap->conv, &ap->offset, &ap->length);
 105	if (error)
 106		return error;
 107	ASSERT(ap->length);
 108	ASSERT(ap->length % mp->m_sb.sb_rextsize == 0);
 109
 110	/*
 111	 * If the offset & length are not perfectly aligned
 112	 * then kill prod, it will just get us in trouble.
 113	 */
 114	if (do_mod(ap->offset, align) || ap->length % align)
 115		prod = 1;
 116	/*
 117	 * Set ralen to be the actual requested length in rtextents.
 118	 */
 119	ralen = ap->length / mp->m_sb.sb_rextsize;
 120	/*
 121	 * If the old value was close enough to MAXEXTLEN that
 122	 * we rounded up to it, cut it back so it's valid again.
 123	 * Note that if it's a really large request (bigger than
 124	 * MAXEXTLEN), we don't hear about that number, and can't
 125	 * adjust the starting point to match it.
 126	 */
 127	if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN)
 128		ralen = MAXEXTLEN / mp->m_sb.sb_rextsize;
 129
 130	/*
 131	 * Lock out modifications to both the RT bitmap and summary inodes
 132	 */
 133	xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
 134	xfs_trans_ijoin(ap->tp, mp->m_rbmip, XFS_ILOCK_EXCL);
 135	xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
 136	xfs_trans_ijoin(ap->tp, mp->m_rsumip, XFS_ILOCK_EXCL);
 137
 138	/*
 139	 * If it's an allocation to an empty file at offset 0,
 140	 * pick an extent that will space things out in the rt area.
 141	 */
 142	if (ap->eof && ap->offset == 0) {
 143		xfs_rtblock_t uninitialized_var(rtx); /* realtime extent no */
 144
 145		error = xfs_rtpick_extent(mp, ap->tp, ralen, &rtx);
 146		if (error)
 147			return error;
 148		ap->blkno = rtx * mp->m_sb.sb_rextsize;
 149	} else {
 150		ap->blkno = 0;
 151	}
 152
 153	xfs_bmap_adjacent(ap);
 
 
 
 
 
 
 
 
 
 
 
 154
 155	/*
 156	 * Realtime allocation, done through xfs_rtallocate_extent.
 157	 */
 158	atype = ap->blkno == 0 ?  XFS_ALLOCTYPE_ANY_AG : XFS_ALLOCTYPE_NEAR_BNO;
 159	do_div(ap->blkno, mp->m_sb.sb_rextsize);
 160	rtb = ap->blkno;
 161	ap->length = ralen;
 162	if ((error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1, ap->length,
 163				&ralen, atype, ap->wasdel, prod, &rtb)))
 164		return error;
 165	if (rtb == NULLFSBLOCK && prod > 1 &&
 166	    (error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1,
 167					   ap->length, &ralen, atype,
 168					   ap->wasdel, 1, &rtb)))
 169		return error;
 170	ap->blkno = rtb;
 171	if (ap->blkno != NULLFSBLOCK) {
 172		ap->blkno *= mp->m_sb.sb_rextsize;
 173		ralen *= mp->m_sb.sb_rextsize;
 174		ap->length = ralen;
 175		ap->ip->i_d.di_nblocks += ralen;
 176		xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
 177		if (ap->wasdel)
 178			ap->ip->i_delayed_blks -= ralen;
 179		/*
 180		 * Adjust the disk quota also. This was reserved
 181		 * earlier.
 182		 */
 183		xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
 184			ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT :
 185					XFS_TRANS_DQ_RTBCOUNT, (long) ralen);
 186
 187		/* Zero the extent if we were asked to do so */
 188		if (ap->datatype & XFS_ALLOC_USERDATA_ZERO) {
 189			error = xfs_zero_extent(ap->ip, ap->blkno, ap->length);
 190			if (error)
 191				return error;
 192		}
 193	} else {
 194		ap->length = 0;
 195	}
 196	return 0;
 
 197}
 198
 199/*
 200 * Check if the endoff is outside the last extent. If so the caller will grow
 201 * the allocation to a stripe unit boundary.  All offsets are considered outside
 202 * the end of file for an empty fork, so 1 is returned in *eof in that case.
 203 */
 204int
 205xfs_bmap_eof(
 
 206	struct xfs_inode	*ip,
 207	xfs_fileoff_t		endoff,
 208	int			whichfork,
 209	int			*eof)
 
 210{
 211	struct xfs_bmbt_irec	rec;
 
 
 
 212	int			error;
 213
 214	error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, eof);
 215	if (error || *eof)
 216		return error;
 217
 218	*eof = endoff >= rec.br_startoff + rec.br_blockcount;
 219	return 0;
 220}
 221
 222/*
 223 * Extent tree block counting routines.
 224 */
 
 
 225
 226/*
 227 * Count leaf blocks given a range of extent records.
 228 */
 229STATIC void
 230xfs_bmap_count_leaves(
 231	xfs_ifork_t		*ifp,
 232	xfs_extnum_t		idx,
 233	int			numrecs,
 234	int			*count)
 235{
 236	int		b;
 237
 238	for (b = 0; b < numrecs; b++) {
 239		xfs_bmbt_rec_host_t *frp = xfs_iext_get_ext(ifp, idx + b);
 240		*count += xfs_bmbt_get_blockcount(frp);
 241	}
 242}
 243
 244/*
 245 * Count leaf blocks given a range of extent records originally
 246 * in btree format.
 247 */
 248STATIC void
 249xfs_bmap_disk_count_leaves(
 250	struct xfs_mount	*mp,
 251	struct xfs_btree_block	*block,
 252	int			numrecs,
 253	int			*count)
 254{
 255	int		b;
 256	xfs_bmbt_rec_t	*frp;
 257
 258	for (b = 1; b <= numrecs; b++) {
 259		frp = XFS_BMBT_REC_ADDR(mp, block, b);
 260		*count += xfs_bmbt_disk_get_blockcount(frp);
 261	}
 
 
 262}
 263
 264/*
 265 * Recursively walks each level of a btree
 266 * to count total fsblocks in use.
 267 */
 268STATIC int                                     /* error */
 269xfs_bmap_count_tree(
 270	xfs_mount_t     *mp,            /* file system mount point */
 271	xfs_trans_t     *tp,            /* transaction pointer */
 272	xfs_ifork_t	*ifp,		/* inode fork pointer */
 273	xfs_fsblock_t   blockno,	/* file system block number */
 274	int             levelin,	/* level in btree */
 275	int		*count)		/* Count of blocks */
 276{
 
 
 277	int			error;
 278	xfs_buf_t		*bp, *nbp;
 279	int			level = levelin;
 280	__be64			*pp;
 281	xfs_fsblock_t           bno = blockno;
 282	xfs_fsblock_t		nextbno;
 283	struct xfs_btree_block	*block, *nextblock;
 284	int			numrecs;
 285
 286	error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp, XFS_BMAP_BTREE_REF,
 287						&xfs_bmbt_buf_ops);
 288	if (error)
 289		return error;
 290	*count += 1;
 291	block = XFS_BUF_TO_BLOCK(bp);
 292
 293	if (--level) {
 294		/* Not at node above leaves, count this level of nodes */
 295		nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 296		while (nextbno != NULLFSBLOCK) {
 297			error = xfs_btree_read_bufl(mp, tp, nextbno, 0, &nbp,
 298						XFS_BMAP_BTREE_REF,
 299						&xfs_bmbt_buf_ops);
 300			if (error)
 301				return error;
 302			*count += 1;
 303			nextblock = XFS_BUF_TO_BLOCK(nbp);
 304			nextbno = be64_to_cpu(nextblock->bb_u.l.bb_rightsib);
 305			xfs_trans_brelse(tp, nbp);
 306		}
 307
 308		/* Dive to the next level */
 309		pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
 310		bno = be64_to_cpu(*pp);
 311		if (unlikely((error =
 312		     xfs_bmap_count_tree(mp, tp, ifp, bno, level, count)) < 0)) {
 313			xfs_trans_brelse(tp, bp);
 314			XFS_ERROR_REPORT("xfs_bmap_count_tree(1)",
 315					 XFS_ERRLEVEL_LOW, mp);
 316			return -EFSCORRUPTED;
 317		}
 318		xfs_trans_brelse(tp, bp);
 319	} else {
 320		/* count all level 1 nodes and their leaves */
 321		for (;;) {
 322			nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 323			numrecs = be16_to_cpu(block->bb_numrecs);
 324			xfs_bmap_disk_count_leaves(mp, block, numrecs, count);
 325			xfs_trans_brelse(tp, bp);
 326			if (nextbno == NULLFSBLOCK)
 327				break;
 328			bno = nextbno;
 329			error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
 330						XFS_BMAP_BTREE_REF,
 331						&xfs_bmbt_buf_ops);
 332			if (error)
 333				return error;
 334			*count += 1;
 335			block = XFS_BUF_TO_BLOCK(bp);
 336		}
 337	}
 338	return 0;
 339}
 340
 341/*
 342 * Count fsblocks of the given fork.
 343 */
 344static int					/* error */
 345xfs_bmap_count_blocks(
 346	xfs_trans_t		*tp,		/* transaction pointer */
 347	xfs_inode_t		*ip,		/* incore inode */
 348	int			whichfork,	/* data or attr fork */
 349	int			*count)		/* out: count of blocks */
 350{
 351	struct xfs_btree_block	*block;	/* current btree block */
 352	xfs_fsblock_t		bno;	/* block # of "block" */
 353	xfs_ifork_t		*ifp;	/* fork structure */
 354	int			level;	/* btree level, for checking */
 355	xfs_mount_t		*mp;	/* file system mount structure */
 356	__be64			*pp;	/* pointer to block address */
 357
 358	bno = NULLFSBLOCK;
 359	mp = ip->i_mount;
 360	ifp = XFS_IFORK_PTR(ip, whichfork);
 361	if ( XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ) {
 362		xfs_bmap_count_leaves(ifp, 0, xfs_iext_count(ifp), count);
 363		return 0;
 364	}
 365
 366	/*
 367	 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
 368	 */
 369	block = ifp->if_broot;
 370	level = be16_to_cpu(block->bb_level);
 371	ASSERT(level > 0);
 372	pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
 373	bno = be64_to_cpu(*pp);
 374	ASSERT(bno != NULLFSBLOCK);
 375	ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
 376	ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
 377
 378	if (unlikely(xfs_bmap_count_tree(mp, tp, ifp, bno, level, count) < 0)) {
 379		XFS_ERROR_REPORT("xfs_bmap_count_blocks(2)", XFS_ERRLEVEL_LOW,
 380				 mp);
 381		return -EFSCORRUPTED;
 382	}
 383
 
 
 
 384	return 0;
 385}
 386
 387/*
 388 * returns 1 for success, 0 if we failed to map the extent.
 389 */
 390STATIC int
 391xfs_getbmapx_fix_eof_hole(
 392	xfs_inode_t		*ip,		/* xfs incore inode pointer */
 393	int			whichfork,
 394	struct getbmapx		*out,		/* output structure */
 395	int			prealloced,	/* this is a file with
 396						 * preallocated data space */
 397	__int64_t		end,		/* last block requested */
 398	xfs_fsblock_t		startblock,
 399	bool			moretocome)
 400{
 401	__int64_t		fixlen;
 402	xfs_mount_t		*mp;		/* file system mount point */
 403	xfs_ifork_t		*ifp;		/* inode fork pointer */
 404	xfs_extnum_t		lastx;		/* last extent pointer */
 405	xfs_fileoff_t		fileblock;
 406
 407	if (startblock == HOLESTARTBLOCK) {
 408		mp = ip->i_mount;
 409		out->bmv_block = -1;
 410		fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, XFS_ISIZE(ip)));
 411		fixlen -= out->bmv_offset;
 412		if (prealloced && out->bmv_offset + out->bmv_length == end) {
 413			/* Came to hole at EOF. Trim it. */
 414			if (fixlen <= 0)
 415				return 0;
 416			out->bmv_length = fixlen;
 417		}
 418	} else {
 419		if (startblock == DELAYSTARTBLOCK)
 420			out->bmv_block = -2;
 421		else
 422			out->bmv_block = xfs_fsb_to_db(ip, startblock);
 423		fileblock = XFS_BB_TO_FSB(ip->i_mount, out->bmv_offset);
 424		ifp = XFS_IFORK_PTR(ip, whichfork);
 425		if (!moretocome &&
 426		    xfs_iext_bno_to_ext(ifp, fileblock, &lastx) &&
 427		   (lastx == xfs_iext_count(ifp) - 1))
 428			out->bmv_oflags |= BMV_OF_LAST;
 429	}
 430
 431	return 1;
 432}
 433
 434/* Adjust the reported bmap around shared/unshared extent transitions. */
 435STATIC int
 436xfs_getbmap_adjust_shared(
 437	struct xfs_inode		*ip,
 438	int				whichfork,
 439	struct xfs_bmbt_irec		*map,
 440	struct getbmapx			*out,
 441	struct xfs_bmbt_irec		*next_map)
 442{
 443	struct xfs_mount		*mp = ip->i_mount;
 444	xfs_agnumber_t			agno;
 445	xfs_agblock_t			agbno;
 446	xfs_agblock_t			ebno;
 447	xfs_extlen_t			elen;
 448	xfs_extlen_t			nlen;
 449	int				error;
 450
 451	next_map->br_startblock = NULLFSBLOCK;
 452	next_map->br_startoff = NULLFILEOFF;
 453	next_map->br_blockcount = 0;
 454
 455	/* Only written data blocks can be shared. */
 456	if (!xfs_is_reflink_inode(ip) || whichfork != XFS_DATA_FORK ||
 457	    map->br_startblock == DELAYSTARTBLOCK ||
 458	    map->br_startblock == HOLESTARTBLOCK ||
 459	    ISUNWRITTEN(map))
 460		return 0;
 461
 462	agno = XFS_FSB_TO_AGNO(mp, map->br_startblock);
 463	agbno = XFS_FSB_TO_AGBNO(mp, map->br_startblock);
 464	error = xfs_reflink_find_shared(mp, agno, agbno, map->br_blockcount,
 465			&ebno, &elen, true);
 466	if (error)
 467		return error;
 468
 469	if (ebno == NULLAGBLOCK) {
 470		/* No shared blocks at all. */
 471		return 0;
 472	} else if (agbno == ebno) {
 473		/*
 474		 * Shared extent at (agbno, elen).  Shrink the reported
 475		 * extent length and prepare to move the start of map[i]
 476		 * to agbno+elen, with the aim of (re)formatting the new
 477		 * map[i] the next time through the inner loop.
 478		 */
 479		out->bmv_length = XFS_FSB_TO_BB(mp, elen);
 480		out->bmv_oflags |= BMV_OF_SHARED;
 481		if (elen != map->br_blockcount) {
 482			*next_map = *map;
 483			next_map->br_startblock += elen;
 484			next_map->br_startoff += elen;
 485			next_map->br_blockcount -= elen;
 486		}
 487		map->br_blockcount -= elen;
 488	} else {
 489		/*
 490		 * There's an unshared extent (agbno, ebno - agbno)
 491		 * followed by shared extent at (ebno, elen).  Shrink
 492		 * the reported extent length to cover only the unshared
 493		 * extent and prepare to move up the start of map[i] to
 494		 * ebno, with the aim of (re)formatting the new map[i]
 495		 * the next time through the inner loop.
 496		 */
 497		*next_map = *map;
 498		nlen = ebno - agbno;
 499		out->bmv_length = XFS_FSB_TO_BB(mp, nlen);
 500		next_map->br_startblock += nlen;
 501		next_map->br_startoff += nlen;
 502		next_map->br_blockcount -= nlen;
 503		map->br_blockcount -= nlen;
 504	}
 505
 506	return 0;
 
 
 
 
 
 
 
 
 507}
 508
 509/*
 510 * Get inode's extents as described in bmv, and format for output.
 511 * Calls formatter to fill the user's buffer until all extents
 512 * are mapped, until the passed-in bmv->bmv_count slots have
 513 * been filled, or until the formatter short-circuits the loop,
 514 * if it is tracking filled-in extents on its own.
 515 */
 516int						/* error code */
 517xfs_getbmap(
 518	xfs_inode_t		*ip,
 519	struct getbmapx		*bmv,		/* user bmap structure */
 520	xfs_bmap_format_t	formatter,	/* format to user */
 521	void			*arg)		/* formatter arg */
 522{
 523	__int64_t		bmvend;		/* last block requested */
 524	int			error = 0;	/* return value */
 525	__int64_t		fixlen;		/* length for -1 case */
 526	int			i;		/* extent number */
 527	int			lock;		/* lock state */
 528	xfs_bmbt_irec_t		*map;		/* buffer for user's data */
 529	xfs_mount_t		*mp;		/* file system mount point */
 530	int			nex;		/* # of user extents can do */
 531	int			subnex;		/* # of bmapi's can do */
 532	int			nmap;		/* number of map entries */
 533	struct getbmapx		*out;		/* output structure */
 534	int			whichfork;	/* data or attr fork */
 535	int			prealloced;	/* this is a file with
 536						 * preallocated data space */
 537	int			iflags;		/* interface flags */
 538	int			bmapi_flags;	/* flags for xfs_bmapi */
 539	int			cur_ext = 0;
 540	struct xfs_bmbt_irec	inject_map;
 541
 542	mp = ip->i_mount;
 543	iflags = bmv->bmv_iflags;
 544
 
 
 545#ifndef DEBUG
 546	/* Only allow CoW fork queries if we're debugging. */
 547	if (iflags & BMV_IF_COWFORK)
 548		return -EINVAL;
 549#endif
 550	if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK))
 551		return -EINVAL;
 552
 
 
 
 
 
 
 553	if (iflags & BMV_IF_ATTRFORK)
 554		whichfork = XFS_ATTR_FORK;
 555	else if (iflags & BMV_IF_COWFORK)
 556		whichfork = XFS_COW_FORK;
 557	else
 558		whichfork = XFS_DATA_FORK;
 559
 
 560	switch (whichfork) {
 561	case XFS_ATTR_FORK:
 562		if (XFS_IFORK_Q(ip)) {
 563			if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS &&
 564			    ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE &&
 565			    ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)
 566				return -EINVAL;
 567		} else if (unlikely(
 568			   ip->i_d.di_aformat != 0 &&
 569			   ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS)) {
 570			XFS_ERROR_REPORT("xfs_getbmap", XFS_ERRLEVEL_LOW,
 571					 ip->i_mount);
 572			return -EFSCORRUPTED;
 573		}
 574
 575		prealloced = 0;
 576		fixlen = 1LL << 32;
 577		break;
 578	case XFS_COW_FORK:
 579		if (ip->i_cformat != XFS_DINODE_FMT_EXTENTS)
 580			return -EINVAL;
 581
 582		if (xfs_get_cowextsz_hint(ip)) {
 583			prealloced = 1;
 584			fixlen = mp->m_super->s_maxbytes;
 585		} else {
 586			prealloced = 0;
 587			fixlen = XFS_ISIZE(ip);
 588		}
 589		break;
 590	default:
 591		if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS &&
 592		    ip->i_d.di_format != XFS_DINODE_FMT_BTREE &&
 593		    ip->i_d.di_format != XFS_DINODE_FMT_LOCAL)
 594			return -EINVAL;
 595
 596		if (xfs_get_extsz_hint(ip) ||
 597		    ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC|XFS_DIFLAG_APPEND)){
 598			prealloced = 1;
 599			fixlen = mp->m_super->s_maxbytes;
 600		} else {
 601			prealloced = 0;
 602			fixlen = XFS_ISIZE(ip);
 603		}
 604		break;
 605	}
 606
 607	if (bmv->bmv_length == -1) {
 608		fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, fixlen));
 609		bmv->bmv_length =
 610			max_t(__int64_t, fixlen - bmv->bmv_offset, 0);
 611	} else if (bmv->bmv_length == 0) {
 612		bmv->bmv_entries = 0;
 613		return 0;
 614	} else if (bmv->bmv_length < 0) {
 615		return -EINVAL;
 616	}
 617
 618	nex = bmv->bmv_count - 1;
 619	if (nex <= 0)
 620		return -EINVAL;
 621	bmvend = bmv->bmv_offset + bmv->bmv_length;
 622
 623
 624	if (bmv->bmv_count > ULONG_MAX / sizeof(struct getbmapx))
 625		return -ENOMEM;
 626	out = kmem_zalloc_large(bmv->bmv_count * sizeof(struct getbmapx), 0);
 627	if (!out)
 628		return -ENOMEM;
 629
 630	xfs_ilock(ip, XFS_IOLOCK_SHARED);
 631	switch (whichfork) {
 632	case XFS_DATA_FORK:
 633		if (!(iflags & BMV_IF_DELALLOC) &&
 634		    (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size)) {
 635			error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
 636			if (error)
 637				goto out_unlock_iolock;
 638
 639			/*
 640			 * Even after flushing the inode, there can still be
 641			 * delalloc blocks on the inode beyond EOF due to
 642			 * speculative preallocation.  These are not removed
 643			 * until the release function is called or the inode
 644			 * is inactivated.  Hence we cannot assert here that
 645			 * ip->i_delayed_blks == 0.
 646			 */
 647		}
 648
 
 
 
 
 
 
 649		lock = xfs_ilock_data_map_shared(ip);
 650		break;
 651	case XFS_COW_FORK:
 652		lock = XFS_ILOCK_SHARED;
 653		xfs_ilock(ip, lock);
 654		break;
 655	case XFS_ATTR_FORK:
 656		lock = xfs_ilock_attr_map_shared(ip);
 657		break;
 658	}
 659
 660	/*
 661	 * Don't let nex be bigger than the number of extents
 662	 * we can have assuming alternating holes and real extents.
 663	 */
 664	if (nex > XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1)
 665		nex = XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1;
 666
 667	bmapi_flags = xfs_bmapi_aflag(whichfork);
 668	if (!(iflags & BMV_IF_PREALLOC))
 669		bmapi_flags |= XFS_BMAPI_IGSTATE;
 670
 671	/*
 672	 * Allocate enough space to handle "subnex" maps at a time.
 673	 */
 674	error = -ENOMEM;
 675	subnex = 16;
 676	map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS);
 677	if (!map)
 678		goto out_unlock_ilock;
 
 
 
 
 679
 680	bmv->bmv_entries = 0;
 681
 682	if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0 &&
 683	    (whichfork == XFS_ATTR_FORK || !(iflags & BMV_IF_DELALLOC))) {
 684		error = 0;
 685		goto out_free_map;
 686	}
 687
 688	do {
 689		nmap = (nex> subnex) ? subnex : nex;
 690		error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset),
 691				       XFS_BB_TO_FSB(mp, bmv->bmv_length),
 692				       map, &nmap, bmapi_flags);
 693		if (error)
 694			goto out_free_map;
 695		ASSERT(nmap <= subnex);
 696
 697		for (i = 0; i < nmap && bmv->bmv_length &&
 698				cur_ext < bmv->bmv_count - 1; i++) {
 699			out[cur_ext].bmv_oflags = 0;
 700			if (map[i].br_state == XFS_EXT_UNWRITTEN)
 701				out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC;
 702			else if (map[i].br_startblock == DELAYSTARTBLOCK)
 703				out[cur_ext].bmv_oflags |= BMV_OF_DELALLOC;
 704			out[cur_ext].bmv_offset =
 705				XFS_FSB_TO_BB(mp, map[i].br_startoff);
 706			out[cur_ext].bmv_length =
 707				XFS_FSB_TO_BB(mp, map[i].br_blockcount);
 708			out[cur_ext].bmv_unused1 = 0;
 709			out[cur_ext].bmv_unused2 = 0;
 710
 711			/*
 712			 * delayed allocation extents that start beyond EOF can
 713			 * occur due to speculative EOF allocation when the
 714			 * delalloc extent is larger than the largest freespace
 715			 * extent at conversion time. These extents cannot be
 716			 * converted by data writeback, so can exist here even
 717			 * if we are not supposed to be finding delalloc
 718			 * extents.
 719			 */
 720			if (map[i].br_startblock == DELAYSTARTBLOCK &&
 721			    map[i].br_startoff <= XFS_B_TO_FSB(mp, XFS_ISIZE(ip)))
 722				ASSERT((iflags & BMV_IF_DELALLOC) != 0);
 723
 724                        if (map[i].br_startblock == HOLESTARTBLOCK &&
 725			    whichfork == XFS_ATTR_FORK) {
 726				/* came to the end of attribute fork */
 727				out[cur_ext].bmv_oflags |= BMV_OF_LAST;
 728				goto out_free_map;
 729			}
 730
 731			/* Is this a shared block? */
 732			error = xfs_getbmap_adjust_shared(ip, whichfork,
 733					&map[i], &out[cur_ext], &inject_map);
 734			if (error)
 735				goto out_free_map;
 
 
 
 
 
 736
 737			if (!xfs_getbmapx_fix_eof_hole(ip, whichfork,
 738					&out[cur_ext], prealloced, bmvend,
 739					map[i].br_startblock,
 740					inject_map.br_startblock != NULLFSBLOCK))
 741				goto out_free_map;
 742
 743			bmv->bmv_offset =
 744				out[cur_ext].bmv_offset +
 745				out[cur_ext].bmv_length;
 746			bmv->bmv_length =
 747				max_t(__int64_t, 0, bmvend - bmv->bmv_offset);
 748
 749			/*
 750			 * In case we don't want to return the hole,
 751			 * don't increase cur_ext so that we can reuse
 752			 * it in the next loop.
 753			 */
 754			if ((iflags & BMV_IF_NO_HOLES) &&
 755			    map[i].br_startblock == HOLESTARTBLOCK) {
 756				memset(&out[cur_ext], 0, sizeof(out[cur_ext]));
 757				continue;
 758			}
 759
 760			/*
 761			 * In order to report shared extents accurately,
 762			 * we report each distinct shared/unshared part
 763			 * of a single bmbt record using multiple bmap
 764			 * extents.  To make that happen, we iterate the
 765			 * same map array item multiple times, each
 766			 * time trimming out the subextent that we just
 767			 * reported.
 768			 *
 769			 * Because of this, we must check the out array
 770			 * index (cur_ext) directly against bmv_count-1
 771			 * to avoid overflows.
 772			 */
 773			if (inject_map.br_startblock != NULLFSBLOCK) {
 774				map[i] = inject_map;
 775				i--;
 
 
 
 
 
 
 
 
 
 776			}
 777			bmv->bmv_entries++;
 778			cur_ext++;
 779		}
 780	} while (nmap && bmv->bmv_length && cur_ext < bmv->bmv_count - 1);
 781
 782 out_free_map:
 783	kmem_free(map);
 784 out_unlock_ilock:
 785	xfs_iunlock(ip, lock);
 786 out_unlock_iolock:
 787	xfs_iunlock(ip, XFS_IOLOCK_SHARED);
 788
 789	for (i = 0; i < cur_ext; i++) {
 790		int full = 0;	/* user array is full */
 791
 792		/* format results & advance arg */
 793		error = formatter(&arg, &out[i], &full);
 794		if (error || full)
 795			break;
 796	}
 797
 798	kmem_free(out);
 
 
 
 799	return error;
 800}
 801
 802/*
 803 * dead simple method of punching delalyed allocation blocks from a range in
 804 * the inode. Walks a block at a time so will be slow, but is only executed in
 805 * rare error cases so the overhead is not critical. This will always punch out
 806 * both the start and end blocks, even if the ranges only partially overlap
 807 * them, so it is up to the caller to ensure that partial blocks are not
 808 * passed in.
 809 */
 810int
 811xfs_bmap_punch_delalloc_range(
 812	struct xfs_inode	*ip,
 813	xfs_fileoff_t		start_fsb,
 814	xfs_fileoff_t		length)
 
 815{
 816	xfs_fileoff_t		remaining = length;
 817	int			error = 0;
 
 
 
 
 818
 819	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 820
 821	do {
 822		int		done;
 823		xfs_bmbt_irec_t	imap;
 824		int		nimaps = 1;
 825		xfs_fsblock_t	firstblock;
 826		struct xfs_defer_ops dfops;
 
 827
 828		/*
 829		 * Map the range first and check that it is a delalloc extent
 830		 * before trying to unmap the range. Otherwise we will be
 831		 * trying to remove a real extent (which requires a
 832		 * transaction) or a hole, which is probably a bad idea...
 833		 */
 834		error = xfs_bmapi_read(ip, start_fsb, 1, &imap, &nimaps,
 835				       XFS_BMAPI_ENTIRE);
 836
 837		if (error) {
 838			/* something screwed, just bail */
 839			if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
 840				xfs_alert(ip->i_mount,
 841			"Failed delalloc mapping lookup ino %lld fsb %lld.",
 842						ip->i_ino, start_fsb);
 843			}
 844			break;
 845		}
 846		if (!nimaps) {
 847			/* nothing there */
 848			goto next_block;
 849		}
 850		if (imap.br_startblock != DELAYSTARTBLOCK) {
 851			/* been converted, ignore */
 852			goto next_block;
 853		}
 854		WARN_ON(imap.br_blockcount == 0);
 855
 856		/*
 857		 * Note: while we initialise the firstblock/dfops pair, they
 858		 * should never be used because blocks should never be
 859		 * allocated or freed for a delalloc extent and hence we need
 860		 * don't cancel or finish them after the xfs_bunmapi() call.
 861		 */
 862		xfs_defer_init(&dfops, &firstblock);
 863		error = xfs_bunmapi(NULL, ip, start_fsb, 1, 0, 1, &firstblock,
 864					&dfops, &done);
 865		if (error)
 866			break;
 
 867
 868		ASSERT(!xfs_defer_has_unfinished_work(&dfops));
 869next_block:
 870		start_fsb++;
 871		remaining--;
 872	} while(remaining > 0);
 873
 874	return error;
 
 875}
 876
 877/*
 878 * Test whether it is appropriate to check an inode for and free post EOF
 879 * blocks. The 'force' parameter determines whether we should also consider
 880 * regular files that are marked preallocated or append-only.
 881 */
 882bool
 883xfs_can_free_eofblocks(struct xfs_inode *ip, bool force)
 
 884{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 885	/* prealloc/delalloc exists only on regular files */
 886	if (!S_ISREG(VFS_I(ip)->i_mode))
 887		return false;
 888
 889	/*
 890	 * Zero sized files with no cached pages and delalloc blocks will not
 891	 * have speculative prealloc/delalloc blocks to remove.
 892	 */
 893	if (VFS_I(ip)->i_size == 0 &&
 894	    VFS_I(ip)->i_mapping->nrpages == 0 &&
 895	    ip->i_delayed_blks == 0)
 896		return false;
 897
 898	/* If we haven't read in the extent list, then don't do it now. */
 899	if (!(ip->i_df.if_flags & XFS_IFEXTENTS))
 900		return false;
 901
 902	/*
 903	 * Do not free real preallocated or append-only files unless the file
 904	 * has delalloc blocks and we are forced to remove them.
 905	 */
 906	if (ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))
 907		if (!force || ip->i_delayed_blks == 0)
 908			return false;
 909
 910	return true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 911}
 912
 913/*
 914 * This is called by xfs_inactive to free any blocks beyond eof
 915 * when the link count isn't zero and by xfs_dm_punch_hole() when
 916 * punching a hole to EOF.
 917 */
 918int
 919xfs_free_eofblocks(
 920	struct xfs_inode	*ip)
 921{
 922	struct xfs_trans	*tp;
 923	int			error;
 924	xfs_fileoff_t		end_fsb;
 925	xfs_fileoff_t		last_fsb;
 926	xfs_filblks_t		map_len;
 927	int			nimaps;
 928	struct xfs_bmbt_irec	imap;
 929	struct xfs_mount	*mp = ip->i_mount;
 
 930
 931	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
 
 
 
 
 
 
 932
 933	/*
 934	 * Figure out if there are any blocks beyond the end
 935	 * of the file.  If not, then there is nothing to do.
 
 
 936	 */
 937	end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip));
 938	last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
 939	if (last_fsb <= end_fsb)
 
 
 
 
 940		return 0;
 941	map_len = last_fsb - end_fsb;
 942
 943	nimaps = 1;
 944	xfs_ilock(ip, XFS_ILOCK_SHARED);
 945	error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0);
 946	xfs_iunlock(ip, XFS_ILOCK_SHARED);
 
 
 
 
 947
 948	/*
 949	 * If there are blocks after the end of file, truncate the file to its
 950	 * current size to free them up.
 
 
 951	 */
 952	if (!error && (nimaps != 0) &&
 953	    (imap.br_startblock != HOLESTARTBLOCK ||
 954	     ip->i_delayed_blks)) {
 955		/*
 956		 * Attach the dquots to the inode up front.
 957		 */
 958		error = xfs_qm_dqattach(ip, 0);
 959		if (error)
 960			return error;
 961
 962		/* wait on dio to ensure i_size has settled */
 963		inode_dio_wait(VFS_I(ip));
 964
 965		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0,
 966				&tp);
 967		if (error) {
 968			ASSERT(XFS_FORCED_SHUTDOWN(mp));
 969			return error;
 970		}
 971
 972		xfs_ilock(ip, XFS_ILOCK_EXCL);
 973		xfs_trans_ijoin(tp, ip, 0);
 
 974
 975		/*
 976		 * Do not update the on-disk file size.  If we update the
 977		 * on-disk file size and then the system crashes before the
 978		 * contents of the file are flushed to disk then the files
 979		 * may be full of holes (ie NULL files bug).
 980		 */
 981		error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK,
 982					      XFS_ISIZE(ip));
 983		if (error) {
 984			/*
 985			 * If we get an error at this point we simply don't
 986			 * bother truncating the file.
 987			 */
 988			xfs_trans_cancel(tp);
 989		} else {
 990			error = xfs_trans_commit(tp);
 991			if (!error)
 992				xfs_inode_clear_eofblocks_tag(ip);
 993		}
 994
 995		xfs_iunlock(ip, XFS_ILOCK_EXCL);
 996	}
 
 
 
 
 
 
 997	return error;
 998}
 999
1000int
1001xfs_alloc_file_space(
1002	struct xfs_inode	*ip,
1003	xfs_off_t		offset,
1004	xfs_off_t		len,
1005	int			alloc_type)
1006{
1007	xfs_mount_t		*mp = ip->i_mount;
1008	xfs_off_t		count;
1009	xfs_filblks_t		allocated_fsb;
1010	xfs_filblks_t		allocatesize_fsb;
1011	xfs_extlen_t		extsz, temp;
1012	xfs_fileoff_t		startoffset_fsb;
1013	xfs_fsblock_t		firstfsb;
1014	int			nimaps;
1015	int			quota_flag;
1016	int			rt;
1017	xfs_trans_t		*tp;
1018	xfs_bmbt_irec_t		imaps[1], *imapp;
1019	struct xfs_defer_ops	dfops;
1020	uint			qblocks, resblks, resrtextents;
1021	int			error;
1022
 
 
 
1023	trace_xfs_alloc_file_space(ip);
1024
1025	if (XFS_FORCED_SHUTDOWN(mp))
1026		return -EIO;
1027
1028	error = xfs_qm_dqattach(ip, 0);
1029	if (error)
1030		return error;
1031
1032	if (len <= 0)
1033		return -EINVAL;
1034
1035	rt = XFS_IS_REALTIME_INODE(ip);
1036	extsz = xfs_get_extsz_hint(ip);
1037
1038	count = len;
1039	imapp = &imaps[0];
1040	nimaps = 1;
1041	startoffset_fsb	= XFS_B_TO_FSBT(mp, offset);
1042	allocatesize_fsb = XFS_B_TO_FSB(mp, count);
 
1043
1044	/*
1045	 * Allocate file space until done or until there is an error
1046	 */
1047	while (allocatesize_fsb && !error) {
1048		xfs_fileoff_t	s, e;
 
 
1049
1050		/*
1051		 * Determine space reservations for data/realtime.
1052		 */
1053		if (unlikely(extsz)) {
1054			s = startoffset_fsb;
1055			do_div(s, extsz);
1056			s *= extsz;
1057			e = startoffset_fsb + allocatesize_fsb;
1058			if ((temp = do_mod(startoffset_fsb, extsz)))
 
1059				e += temp;
1060			if ((temp = do_mod(e, extsz)))
 
1061				e += extsz - temp;
1062		} else {
1063			s = 0;
1064			e = allocatesize_fsb;
1065		}
1066
1067		/*
1068		 * The transaction reservation is limited to a 32-bit block
1069		 * count, hence we need to limit the number of blocks we are
1070		 * trying to reserve to avoid an overflow. We can't allocate
1071		 * more than @nimaps extents, and an extent is limited on disk
1072		 * to MAXEXTLEN (21 bits), so use that to enforce the limit.
 
1073		 */
1074		resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps));
 
1075		if (unlikely(rt)) {
1076			resrtextents = qblocks = resblks;
1077			resrtextents /= mp->m_sb.sb_rextsize;
1078			resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1079			quota_flag = XFS_QMOPT_RES_RTBLKS;
1080		} else {
1081			resrtextents = 0;
1082			resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks);
1083			quota_flag = XFS_QMOPT_RES_REGBLKS;
1084		}
1085
1086		/*
1087		 * Allocate and setup the transaction.
1088		 */
1089		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks,
1090				resrtextents, 0, &tp);
1091
1092		/*
1093		 * Check for running out of space
1094		 */
1095		if (error) {
1096			/*
1097			 * Free the transaction structure.
1098			 */
1099			ASSERT(error == -ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1100			break;
1101		}
1102		xfs_ilock(ip, XFS_ILOCK_EXCL);
1103		error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
1104						      0, quota_flag);
1105		if (error)
1106			goto error1;
1107
1108		xfs_trans_ijoin(tp, ip, 0);
1109
1110		xfs_defer_init(&dfops, &firstfsb);
1111		error = xfs_bmapi_write(tp, ip, startoffset_fsb,
1112					allocatesize_fsb, alloc_type, &firstfsb,
1113					resblks, imapp, &nimaps, &dfops);
1114		if (error)
1115			goto error0;
1116
1117		/*
1118		 * Complete the transaction
 
 
 
 
 
 
1119		 */
1120		error = xfs_defer_finish(&tp, &dfops, NULL);
1121		if (error)
1122			goto error0;
 
 
 
 
 
 
 
 
 
 
 
1123
1124		error = xfs_trans_commit(tp);
1125		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1126		if (error)
1127			break;
1128
1129		allocated_fsb = imapp->br_blockcount;
1130
1131		if (nimaps == 0) {
1132			error = -ENOSPC;
1133			break;
1134		}
1135
1136		startoffset_fsb += allocated_fsb;
1137		allocatesize_fsb -= allocated_fsb;
1138	}
1139
1140	return error;
1141
1142error0:	/* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
1143	xfs_defer_cancel(&dfops);
1144	xfs_trans_unreserve_quota_nblks(tp, ip, (long)qblocks, 0, quota_flag);
1145
1146error1:	/* Just cancel transaction */
1147	xfs_trans_cancel(tp);
1148	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1149	return error;
1150}
1151
1152static int
1153xfs_unmap_extent(
1154	struct xfs_inode	*ip,
1155	xfs_fileoff_t		startoffset_fsb,
1156	xfs_filblks_t		len_fsb,
1157	int			*done)
1158{
1159	struct xfs_mount	*mp = ip->i_mount;
1160	struct xfs_trans	*tp;
1161	struct xfs_defer_ops	dfops;
1162	xfs_fsblock_t		firstfsb;
1163	uint			resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1164	int			error;
1165
1166	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
1167	if (error) {
1168		ASSERT(error == -ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1169		return error;
1170	}
1171
1172	xfs_ilock(ip, XFS_ILOCK_EXCL);
1173	error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot, ip->i_gdquot,
1174			ip->i_pdquot, resblks, 0, XFS_QMOPT_RES_REGBLKS);
1175	if (error)
1176		goto out_trans_cancel;
1177
1178	xfs_trans_ijoin(tp, ip, 0);
1179
1180	xfs_defer_init(&dfops, &firstfsb);
1181	error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, &firstfsb,
1182			&dfops, done);
1183	if (error)
1184		goto out_bmap_cancel;
1185
1186	error = xfs_defer_finish(&tp, &dfops, ip);
1187	if (error)
1188		goto out_bmap_cancel;
1189
1190	error = xfs_trans_commit(tp);
1191out_unlock:
1192	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1193	return error;
1194
1195out_bmap_cancel:
1196	xfs_defer_cancel(&dfops);
1197out_trans_cancel:
1198	xfs_trans_cancel(tp);
1199	goto out_unlock;
1200}
1201
1202static int
1203xfs_adjust_extent_unmap_boundaries(
1204	struct xfs_inode	*ip,
1205	xfs_fileoff_t		*startoffset_fsb,
1206	xfs_fileoff_t		*endoffset_fsb)
1207{
1208	struct xfs_mount	*mp = ip->i_mount;
1209	struct xfs_bmbt_irec	imap;
1210	int			nimap, error;
1211	xfs_extlen_t		mod = 0;
1212
1213	nimap = 1;
1214	error = xfs_bmapi_read(ip, *startoffset_fsb, 1, &imap, &nimap, 0);
1215	if (error)
1216		return error;
1217
1218	if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1219		xfs_daddr_t	block;
1220
1221		ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1222		block = imap.br_startblock;
1223		mod = do_div(block, mp->m_sb.sb_rextsize);
1224		if (mod)
1225			*startoffset_fsb += mp->m_sb.sb_rextsize - mod;
1226	}
1227
1228	nimap = 1;
1229	error = xfs_bmapi_read(ip, *endoffset_fsb - 1, 1, &imap, &nimap, 0);
1230	if (error)
1231		return error;
1232
1233	if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1234		ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1235		mod++;
1236		if (mod && mod != mp->m_sb.sb_rextsize)
1237			*endoffset_fsb -= mod;
1238	}
1239
1240	return 0;
1241}
1242
1243static int
1244xfs_flush_unmap_range(
1245	struct xfs_inode	*ip,
1246	xfs_off_t		offset,
1247	xfs_off_t		len)
1248{
1249	struct xfs_mount	*mp = ip->i_mount;
1250	struct inode		*inode = VFS_I(ip);
1251	xfs_off_t		rounding, start, end;
1252	int			error;
1253
1254	/* wait for the completion of any pending DIOs */
1255	inode_dio_wait(inode);
1256
1257	rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_SIZE);
1258	start = round_down(offset, rounding);
1259	end = round_up(offset + len, rounding) - 1;
 
 
1260
1261	error = filemap_write_and_wait_range(inode->i_mapping, start, end);
1262	if (error)
1263		return error;
1264	truncate_pagecache_range(inode, start, end);
1265	return 0;
1266}
1267
1268int
1269xfs_free_file_space(
1270	struct xfs_inode	*ip,
1271	xfs_off_t		offset,
1272	xfs_off_t		len)
1273{
1274	struct xfs_mount	*mp = ip->i_mount;
1275	xfs_fileoff_t		startoffset_fsb;
1276	xfs_fileoff_t		endoffset_fsb;
1277	int			done = 0, error;
1278
1279	trace_xfs_free_file_space(ip);
1280
1281	error = xfs_qm_dqattach(ip, 0);
1282	if (error)
1283		return error;
1284
1285	if (len <= 0)	/* if nothing being freed */
1286		return 0;
1287
 
 
 
 
1288	error = xfs_flush_unmap_range(ip, offset, len);
1289	if (error)
1290		return error;
1291
1292	startoffset_fsb = XFS_B_TO_FSB(mp, offset);
1293	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
1294
1295	/*
1296	 * Need to zero the stuff we're not freeing, on disk.  If it's a RT file
1297	 * and we can't use unwritten extents then we actually need to ensure
1298	 * to zero the whole extent, otherwise we just need to take of block
1299	 * boundaries, and xfs_bunmapi will handle the rest.
1300	 */
1301	if (XFS_IS_REALTIME_INODE(ip) &&
1302	    !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
1303		error = xfs_adjust_extent_unmap_boundaries(ip, &startoffset_fsb,
1304				&endoffset_fsb);
1305		if (error)
1306			return error;
1307	}
1308
 
 
 
1309	if (endoffset_fsb > startoffset_fsb) {
1310		while (!done) {
1311			error = xfs_unmap_extent(ip, startoffset_fsb,
1312					endoffset_fsb - startoffset_fsb, &done);
1313			if (error)
1314				return error;
1315		}
1316	}
1317
1318	/*
1319	 * Now that we've unmap all full blocks we'll have to zero out any
1320	 * partial block at the beginning and/or end.  xfs_zero_range is
1321	 * smart enough to skip any holes, including those we just created,
1322	 * but we must take care not to zero beyond EOF and enlarge i_size.
1323	 */
1324
1325	if (offset >= XFS_ISIZE(ip))
1326		return 0;
1327
1328	if (offset + len > XFS_ISIZE(ip))
1329		len = XFS_ISIZE(ip) - offset;
1330
1331	return xfs_zero_range(ip, offset, len, NULL);
1332}
1333
1334/*
1335 * Preallocate and zero a range of a file. This mechanism has the allocation
1336 * semantics of fallocate and in addition converts data in the range to zeroes.
1337 */
1338int
1339xfs_zero_file_space(
1340	struct xfs_inode	*ip,
1341	xfs_off_t		offset,
1342	xfs_off_t		len)
1343{
1344	struct xfs_mount	*mp = ip->i_mount;
1345	uint			blksize;
1346	int			error;
1347
1348	trace_xfs_zero_file_space(ip);
1349
1350	blksize = 1 << mp->m_sb.sb_blocklog;
1351
1352	/*
1353	 * Punch a hole and prealloc the range. We use hole punch rather than
1354	 * unwritten extent conversion for two reasons:
1355	 *
1356	 * 1.) Hole punch handles partial block zeroing for us.
1357	 *
1358	 * 2.) If prealloc returns ENOSPC, the file range is still zero-valued
1359	 * by virtue of the hole punch.
1360	 */
1361	error = xfs_free_file_space(ip, offset, len);
1362	if (error)
1363		goto out;
1364
1365	error = xfs_alloc_file_space(ip, round_down(offset, blksize),
1366				     round_up(offset + len, blksize) -
1367				     round_down(offset, blksize),
1368				     XFS_BMAPI_PREALLOC);
1369out:
1370	return error;
1371
1372}
1373
1374/*
1375 * @next_fsb will keep track of the extent currently undergoing shift.
1376 * @stop_fsb will keep track of the extent at which we have to stop.
1377 * If we are shifting left, we will start with block (offset + len) and
1378 * shift each extent till last extent.
1379 * If we are shifting right, we will start with last extent inside file space
1380 * and continue until we reach the block corresponding to offset.
1381 */
1382static int
1383xfs_shift_file_space(
1384	struct xfs_inode        *ip,
1385	xfs_off_t               offset,
1386	xfs_off_t               len,
1387	enum shift_direction	direction)
1388{
1389	int			done = 0;
1390	struct xfs_mount	*mp = ip->i_mount;
1391	struct xfs_trans	*tp;
1392	int			error;
1393	struct xfs_defer_ops	dfops;
1394	xfs_fsblock_t		first_block;
1395	xfs_fileoff_t		stop_fsb;
1396	xfs_fileoff_t		next_fsb;
1397	xfs_fileoff_t		shift_fsb;
1398	uint			resblks;
1399
1400	ASSERT(direction == SHIFT_LEFT || direction == SHIFT_RIGHT);
1401
1402	if (direction == SHIFT_LEFT) {
1403		/*
1404		 * Reserve blocks to cover potential extent merges after left
1405		 * shift operations.
1406		 */
1407		resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1408		next_fsb = XFS_B_TO_FSB(mp, offset + len);
1409		stop_fsb = XFS_B_TO_FSB(mp, VFS_I(ip)->i_size);
1410	} else {
1411		/*
1412		 * If right shift, delegate the work of initialization of
1413		 * next_fsb to xfs_bmap_shift_extent as it has ilock held.
1414		 */
1415		resblks = 0;
1416		next_fsb = NULLFSBLOCK;
1417		stop_fsb = XFS_B_TO_FSB(mp, offset);
1418	}
1419
1420	shift_fsb = XFS_B_TO_FSB(mp, len);
1421
1422	/*
1423	 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation
1424	 * into the accessible region of the file.
1425	 */
1426	if (xfs_can_free_eofblocks(ip, true)) {
1427		error = xfs_free_eofblocks(ip);
1428		if (error)
1429			return error;
1430	}
1431
1432	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
1433	 * Writeback and invalidate cache for the remainder of the file as we're
1434	 * about to shift down every extent from offset to EOF.
1435	 */
1436	error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
1437					     offset, -1);
1438	if (error)
1439		return error;
1440	error = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
1441					offset >> PAGE_SHIFT, -1);
1442	if (error)
1443		return error;
1444
1445	/*
1446	 * The extent shiting code works on extent granularity. So, if
1447	 * stop_fsb is not the starting block of extent, we need to split
1448	 * the extent at stop_fsb.
1449	 */
1450	if (direction == SHIFT_RIGHT) {
1451		error = xfs_bmap_split_extent(ip, stop_fsb);
 
1452		if (error)
1453			return error;
1454	}
1455
1456	while (!error && !done) {
1457		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0,
1458					&tp);
1459		if (error)
1460			break;
1461
1462		xfs_ilock(ip, XFS_ILOCK_EXCL);
1463		error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot,
1464				ip->i_gdquot, ip->i_pdquot, resblks, 0,
1465				XFS_QMOPT_RES_REGBLKS);
1466		if (error)
1467			goto out_trans_cancel;
1468
1469		xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1470
1471		xfs_defer_init(&dfops, &first_block);
1472
1473		/*
1474		 * We are using the write transaction in which max 2 bmbt
1475		 * updates are allowed
1476		 */
1477		error = xfs_bmap_shift_extents(tp, ip, &next_fsb, shift_fsb,
1478				&done, stop_fsb, &first_block, &dfops,
1479				direction, XFS_BMAP_MAX_SHIFT_EXTENTS);
1480		if (error)
1481			goto out_bmap_cancel;
1482
1483		error = xfs_defer_finish(&tp, &dfops, NULL);
1484		if (error)
1485			goto out_bmap_cancel;
1486
1487		error = xfs_trans_commit(tp);
1488	}
1489
1490	return error;
1491
1492out_bmap_cancel:
1493	xfs_defer_cancel(&dfops);
1494out_trans_cancel:
1495	xfs_trans_cancel(tp);
1496	return error;
1497}
1498
1499/*
1500 * xfs_collapse_file_space()
1501 *	This routine frees disk space and shift extent for the given file.
1502 *	The first thing we do is to free data blocks in the specified range
1503 *	by calling xfs_free_file_space(). It would also sync dirty data
1504 *	and invalidate page cache over the region on which collapse range
1505 *	is working. And Shift extent records to the left to cover a hole.
1506 * RETURNS:
1507 *	0 on success
1508 *	errno on error
1509 *
1510 */
1511int
1512xfs_collapse_file_space(
1513	struct xfs_inode	*ip,
1514	xfs_off_t		offset,
1515	xfs_off_t		len)
1516{
1517	int error;
 
 
 
 
 
 
 
1518
1519	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1520	trace_xfs_collapse_file_space(ip);
1521
1522	error = xfs_free_file_space(ip, offset, len);
1523	if (error)
1524		return error;
1525
1526	return xfs_shift_file_space(ip, offset, len, SHIFT_LEFT);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1527}
1528
1529/*
1530 * xfs_insert_file_space()
1531 *	This routine create hole space by shifting extents for the given file.
1532 *	The first thing we do is to sync dirty data and invalidate page cache
1533 *	over the region on which insert range is working. And split an extent
1534 *	to two extents at given offset by calling xfs_bmap_split_extent.
1535 *	And shift all extent records which are laying between [offset,
1536 *	last allocated extent] to the right to reserve hole range.
1537 * RETURNS:
1538 *	0 on success
1539 *	errno on error
1540 */
1541int
1542xfs_insert_file_space(
1543	struct xfs_inode	*ip,
1544	loff_t			offset,
1545	loff_t			len)
1546{
1547	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
 
 
 
 
 
 
 
 
 
1548	trace_xfs_insert_file_space(ip);
1549
1550	return xfs_shift_file_space(ip, offset, len, SHIFT_RIGHT);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1551}
1552
1553/*
1554 * We need to check that the format of the data fork in the temporary inode is
1555 * valid for the target inode before doing the swap. This is not a problem with
1556 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized
1557 * data fork depending on the space the attribute fork is taking so we can get
1558 * invalid formats on the target inode.
1559 *
1560 * E.g. target has space for 7 extents in extent format, temp inode only has
1561 * space for 6.  If we defragment down to 7 extents, then the tmp format is a
1562 * btree, but when swapped it needs to be in extent format. Hence we can't just
1563 * blindly swap data forks on attr2 filesystems.
1564 *
1565 * Note that we check the swap in both directions so that we don't end up with
1566 * a corrupt temporary inode, either.
1567 *
1568 * Note that fixing the way xfs_fsr sets up the attribute fork in the source
1569 * inode will prevent this situation from occurring, so all we do here is
1570 * reject and log the attempt. basically we are putting the responsibility on
1571 * userspace to get this right.
1572 */
1573static int
1574xfs_swap_extents_check_format(
1575	struct xfs_inode	*ip,	/* target inode */
1576	struct xfs_inode	*tip)	/* tmp inode */
1577{
 
 
 
 
 
 
 
 
 
1578
1579	/* Should never get a local format */
1580	if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL ||
1581	    tip->i_d.di_format == XFS_DINODE_FMT_LOCAL)
1582		return -EINVAL;
1583
1584	/*
1585	 * if the target inode has less extents that then temporary inode then
1586	 * why did userspace call us?
1587	 */
1588	if (ip->i_d.di_nextents < tip->i_d.di_nextents)
1589		return -EINVAL;
1590
1591	/*
1592	 * If we have to use the (expensive) rmap swap method, we can
1593	 * handle any number of extents and any format.
1594	 */
1595	if (xfs_sb_version_hasrmapbt(&ip->i_mount->m_sb))
1596		return 0;
1597
1598	/*
1599	 * if the target inode is in extent form and the temp inode is in btree
1600	 * form then we will end up with the target inode in the wrong format
1601	 * as we already know there are less extents in the temp inode.
1602	 */
1603	if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1604	    tip->i_d.di_format == XFS_DINODE_FMT_BTREE)
1605		return -EINVAL;
1606
1607	/* Check temp in extent form to max in target */
1608	if (tip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1609	    XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) >
1610			XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1611		return -EINVAL;
1612
1613	/* Check target in extent form to max in temp */
1614	if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1615	    XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) >
1616			XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1617		return -EINVAL;
1618
1619	/*
1620	 * If we are in a btree format, check that the temp root block will fit
1621	 * in the target and that it has enough extents to be in btree format
1622	 * in the target.
1623	 *
1624	 * Note that we have to be careful to allow btree->extent conversions
1625	 * (a common defrag case) which will occur when the temp inode is in
1626	 * extent format...
1627	 */
1628	if (tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1629		if (XFS_IFORK_BOFF(ip) &&
1630		    XFS_BMAP_BMDR_SPACE(tip->i_df.if_broot) > XFS_IFORK_BOFF(ip))
1631			return -EINVAL;
1632		if (XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) <=
1633		    XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1634			return -EINVAL;
1635	}
1636
1637	/* Reciprocal target->temp btree format checks */
1638	if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1639		if (XFS_IFORK_BOFF(tip) &&
1640		    XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > XFS_IFORK_BOFF(tip))
1641			return -EINVAL;
1642		if (XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) <=
1643		    XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1644			return -EINVAL;
1645	}
1646
1647	return 0;
1648}
1649
1650static int
1651xfs_swap_extent_flush(
1652	struct xfs_inode	*ip)
1653{
1654	int	error;
1655
1656	error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
1657	if (error)
1658		return error;
1659	truncate_pagecache_range(VFS_I(ip), 0, -1);
1660
1661	/* Verify O_DIRECT for ftmp */
1662	if (VFS_I(ip)->i_mapping->nrpages)
1663		return -EINVAL;
1664	return 0;
1665}
1666
1667/*
1668 * Move extents from one file to another, when rmap is enabled.
1669 */
1670STATIC int
1671xfs_swap_extent_rmap(
1672	struct xfs_trans		**tpp,
1673	struct xfs_inode		*ip,
1674	struct xfs_inode		*tip)
1675{
 
1676	struct xfs_bmbt_irec		irec;
1677	struct xfs_bmbt_irec		uirec;
1678	struct xfs_bmbt_irec		tirec;
1679	xfs_fileoff_t			offset_fsb;
1680	xfs_fileoff_t			end_fsb;
1681	xfs_filblks_t			count_fsb;
1682	xfs_fsblock_t			firstfsb;
1683	struct xfs_defer_ops		dfops;
1684	int				error;
1685	xfs_filblks_t			ilen;
1686	xfs_filblks_t			rlen;
1687	int				nimaps;
1688	__uint64_t			tip_flags2;
1689
1690	/*
1691	 * If the source file has shared blocks, we must flag the donor
1692	 * file as having shared blocks so that we get the shared-block
1693	 * rmap functions when we go to fix up the rmaps.  The flags
1694	 * will be switch for reals later.
1695	 */
1696	tip_flags2 = tip->i_d.di_flags2;
1697	if (ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK)
1698		tip->i_d.di_flags2 |= XFS_DIFLAG2_REFLINK;
1699
1700	offset_fsb = 0;
1701	end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip)));
1702	count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb);
1703
1704	while (count_fsb) {
1705		/* Read extent from the donor file */
1706		nimaps = 1;
1707		error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec,
1708				&nimaps, 0);
1709		if (error)
1710			goto out;
1711		ASSERT(nimaps == 1);
1712		ASSERT(tirec.br_startblock != DELAYSTARTBLOCK);
1713
1714		trace_xfs_swap_extent_rmap_remap(tip, &tirec);
1715		ilen = tirec.br_blockcount;
1716
1717		/* Unmap the old blocks in the source file. */
1718		while (tirec.br_blockcount) {
1719			xfs_defer_init(&dfops, &firstfsb);
1720			trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec);
1721
1722			/* Read extent from the source file */
1723			nimaps = 1;
1724			error = xfs_bmapi_read(ip, tirec.br_startoff,
1725					tirec.br_blockcount, &irec,
1726					&nimaps, 0);
1727			if (error)
1728				goto out_defer;
1729			ASSERT(nimaps == 1);
1730			ASSERT(tirec.br_startoff == irec.br_startoff);
1731			trace_xfs_swap_extent_rmap_remap_piece(ip, &irec);
1732
1733			/* Trim the extent. */
1734			uirec = tirec;
1735			uirec.br_blockcount = rlen = min_t(xfs_filblks_t,
1736					tirec.br_blockcount,
1737					irec.br_blockcount);
1738			trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec);
1739
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1740			/* Remove the mapping from the donor file. */
1741			error = xfs_bmap_unmap_extent((*tpp)->t_mountp, &dfops,
1742					tip, &uirec);
1743			if (error)
1744				goto out_defer;
1745
1746			/* Remove the mapping from the source file. */
1747			error = xfs_bmap_unmap_extent((*tpp)->t_mountp, &dfops,
1748					ip, &irec);
1749			if (error)
1750				goto out_defer;
1751
1752			/* Map the donor file's blocks into the source file. */
1753			error = xfs_bmap_map_extent((*tpp)->t_mountp, &dfops,
1754					ip, &uirec);
1755			if (error)
1756				goto out_defer;
1757
1758			/* Map the source file's blocks into the donor file. */
1759			error = xfs_bmap_map_extent((*tpp)->t_mountp, &dfops,
1760					tip, &irec);
1761			if (error)
1762				goto out_defer;
1763
1764			error = xfs_defer_finish(tpp, &dfops, ip);
 
1765			if (error)
1766				goto out_defer;
1767
1768			tirec.br_startoff += rlen;
1769			if (tirec.br_startblock != HOLESTARTBLOCK &&
1770			    tirec.br_startblock != DELAYSTARTBLOCK)
1771				tirec.br_startblock += rlen;
1772			tirec.br_blockcount -= rlen;
1773		}
1774
1775		/* Roll on... */
1776		count_fsb -= ilen;
1777		offset_fsb += ilen;
1778	}
1779
1780	tip->i_d.di_flags2 = tip_flags2;
1781	return 0;
1782
1783out_defer:
1784	xfs_defer_cancel(&dfops);
1785out:
1786	trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_);
1787	tip->i_d.di_flags2 = tip_flags2;
1788	return error;
1789}
1790
1791/* Swap the extents of two files by swapping data forks. */
1792STATIC int
1793xfs_swap_extent_forks(
1794	struct xfs_trans	*tp,
1795	struct xfs_inode	*ip,
1796	struct xfs_inode	*tip,
1797	int			*src_log_flags,
1798	int			*target_log_flags)
1799{
1800	struct xfs_ifork	tempifp, *ifp, *tifp;
1801	int			aforkblks = 0;
1802	int			taforkblks = 0;
1803	xfs_extnum_t		nextents;
1804	__uint64_t		tmp;
1805	int			error;
1806
1807	/*
1808	 * Count the number of extended attribute blocks
1809	 */
1810	if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
1811	     (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
1812		error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK,
1813				&aforkblks);
1814		if (error)
1815			return error;
1816	}
1817	if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
1818	     (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
1819		error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
1820				&taforkblks);
1821		if (error)
1822			return error;
1823	}
1824
1825	/*
1826	 * Before we've swapped the forks, lets set the owners of the forks
1827	 * appropriately. We have to do this as we are demand paging the btree
1828	 * buffers, and so the validation done on read will expect the owner
1829	 * field to be correctly set. Once we change the owners, we can swap the
1830	 * inode forks.
1831	 */
1832	if (ip->i_d.di_version == 3 &&
1833	    ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1834		(*target_log_flags) |= XFS_ILOG_DOWNER;
1835		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK,
1836					      tip->i_ino, NULL);
1837		if (error)
1838			return error;
1839	}
1840
1841	if (tip->i_d.di_version == 3 &&
1842	    tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1843		(*src_log_flags) |= XFS_ILOG_DOWNER;
1844		error = xfs_bmbt_change_owner(tp, tip, XFS_DATA_FORK,
1845					      ip->i_ino, NULL);
1846		if (error)
1847			return error;
1848	}
1849
1850	/*
1851	 * Swap the data forks of the inodes
1852	 */
1853	ifp = &ip->i_df;
1854	tifp = &tip->i_df;
1855	tempifp = *ifp;		/* struct copy */
1856	*ifp = *tifp;		/* struct copy */
1857	*tifp = tempifp;	/* struct copy */
1858
1859	/*
1860	 * Fix the on-disk inode values
1861	 */
1862	tmp = (__uint64_t)ip->i_d.di_nblocks;
1863	ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
1864	tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;
1865
1866	tmp = (__uint64_t) ip->i_d.di_nextents;
1867	ip->i_d.di_nextents = tip->i_d.di_nextents;
1868	tip->i_d.di_nextents = tmp;
1869
1870	tmp = (__uint64_t) ip->i_d.di_format;
1871	ip->i_d.di_format = tip->i_d.di_format;
1872	tip->i_d.di_format = tmp;
1873
1874	/*
1875	 * The extents in the source inode could still contain speculative
1876	 * preallocation beyond EOF (e.g. the file is open but not modified
1877	 * while defrag is in progress). In that case, we need to copy over the
1878	 * number of delalloc blocks the data fork in the source inode is
1879	 * tracking beyond EOF so that when the fork is truncated away when the
1880	 * temporary inode is unlinked we don't underrun the i_delayed_blks
1881	 * counter on that inode.
1882	 */
1883	ASSERT(tip->i_delayed_blks == 0);
1884	tip->i_delayed_blks = ip->i_delayed_blks;
1885	ip->i_delayed_blks = 0;
1886
1887	switch (ip->i_d.di_format) {
1888	case XFS_DINODE_FMT_EXTENTS:
1889		/*
1890		 * If the extents fit in the inode, fix the pointer.  Otherwise
1891		 * it's already NULL or pointing to the extent.
1892		 */
1893		nextents = xfs_iext_count(&ip->i_df);
1894		if (nextents <= XFS_INLINE_EXTS)
1895			ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
1896		(*src_log_flags) |= XFS_ILOG_DEXT;
1897		break;
1898	case XFS_DINODE_FMT_BTREE:
1899		ASSERT(ip->i_d.di_version < 3 ||
1900		       (*src_log_flags & XFS_ILOG_DOWNER));
1901		(*src_log_flags) |= XFS_ILOG_DBROOT;
1902		break;
1903	}
1904
1905	switch (tip->i_d.di_format) {
1906	case XFS_DINODE_FMT_EXTENTS:
1907		/*
1908		 * If the extents fit in the inode, fix the pointer.  Otherwise
1909		 * it's already NULL or pointing to the extent.
1910		 */
1911		nextents = xfs_iext_count(&tip->i_df);
1912		if (nextents <= XFS_INLINE_EXTS)
1913			tifp->if_u1.if_extents = tifp->if_u2.if_inline_ext;
1914		(*target_log_flags) |= XFS_ILOG_DEXT;
1915		break;
1916	case XFS_DINODE_FMT_BTREE:
1917		(*target_log_flags) |= XFS_ILOG_DBROOT;
1918		ASSERT(tip->i_d.di_version < 3 ||
1919		       (*target_log_flags & XFS_ILOG_DOWNER));
1920		break;
1921	}
1922
1923	return 0;
1924}
1925
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1926int
1927xfs_swap_extents(
1928	struct xfs_inode	*ip,	/* target inode */
1929	struct xfs_inode	*tip,	/* tmp inode */
1930	struct xfs_swapext	*sxp)
1931{
1932	struct xfs_mount	*mp = ip->i_mount;
1933	struct xfs_trans	*tp;
1934	struct xfs_bstat	*sbp = &sxp->sx_stat;
1935	int			src_log_flags, target_log_flags;
1936	int			error = 0;
1937	int			lock_flags;
1938	struct xfs_ifork	*cowfp;
1939	__uint64_t		f;
1940	int			resblks;
1941
1942	/*
1943	 * Lock the inodes against other IO, page faults and truncate to
1944	 * begin with.  Then we can ensure the inodes are flushed and have no
1945	 * page cache safely. Once we have done this we can take the ilocks and
1946	 * do the rest of the checks.
1947	 */
1948	lock_two_nondirectories(VFS_I(ip), VFS_I(tip));
1949	lock_flags = XFS_MMAPLOCK_EXCL;
1950	xfs_lock_two_inodes(ip, tip, XFS_MMAPLOCK_EXCL);
1951
1952	/* Verify that both files have the same format */
1953	if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) {
1954		error = -EINVAL;
1955		goto out_unlock;
1956	}
1957
1958	/* Verify both files are either real-time or non-realtime */
1959	if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
1960		error = -EINVAL;
1961		goto out_unlock;
1962	}
1963
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1964	error = xfs_swap_extent_flush(ip);
1965	if (error)
1966		goto out_unlock;
1967	error = xfs_swap_extent_flush(tip);
1968	if (error)
1969		goto out_unlock;
1970
 
 
 
 
 
 
1971	/*
1972	 * Extent "swapping" with rmap requires a permanent reservation and
1973	 * a block reservation because it's really just a remap operation
1974	 * performed with log redo items!
1975	 */
1976	if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
 
 
 
 
1977		/*
1978		 * Conceptually this shouldn't affect the shape of either
1979		 * bmbt, but since we atomically move extents one by one,
1980		 * we reserve enough space to rebuild both trees.
1981		 */
1982		resblks = XFS_SWAP_RMAP_SPACE_RES(mp,
1983				XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK),
1984				XFS_DATA_FORK) +
1985			  XFS_SWAP_RMAP_SPACE_RES(mp,
1986				XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK),
1987				XFS_DATA_FORK);
1988		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks,
1989				0, 0, &tp);
1990	} else
1991		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0,
1992				0, 0, &tp);
 
 
 
1993	if (error)
1994		goto out_unlock;
1995
1996	/*
1997	 * Lock and join the inodes to the tansaction so that transaction commit
1998	 * or cancel will unlock the inodes from this point onwards.
1999	 */
2000	xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);
2001	lock_flags |= XFS_ILOCK_EXCL;
2002	xfs_trans_ijoin(tp, ip, 0);
2003	xfs_trans_ijoin(tp, tip, 0);
2004
2005
2006	/* Verify all data are being swapped */
2007	if (sxp->sx_offset != 0 ||
2008	    sxp->sx_length != ip->i_d.di_size ||
2009	    sxp->sx_length != tip->i_d.di_size) {
2010		error = -EFAULT;
2011		goto out_trans_cancel;
2012	}
2013
2014	trace_xfs_swap_extent_before(ip, 0);
2015	trace_xfs_swap_extent_before(tip, 1);
2016
2017	/* check inode formats now that data is flushed */
2018	error = xfs_swap_extents_check_format(ip, tip);
2019	if (error) {
2020		xfs_notice(mp,
2021		    "%s: inode 0x%llx format is incompatible for exchanging.",
2022				__func__, ip->i_ino);
2023		goto out_trans_cancel;
2024	}
2025
2026	/*
2027	 * Compare the current change & modify times with that
2028	 * passed in.  If they differ, we abort this swap.
2029	 * This is the mechanism used to ensure the calling
2030	 * process that the file was not changed out from
2031	 * under it.
2032	 */
2033	if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) ||
2034	    (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) ||
2035	    (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) ||
2036	    (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) {
 
 
2037		error = -EBUSY;
2038		goto out_trans_cancel;
2039	}
2040
2041	/*
2042	 * Note the trickiness in setting the log flags - we set the owner log
2043	 * flag on the opposite inode (i.e. the inode we are setting the new
2044	 * owner to be) because once we swap the forks and log that, log
2045	 * recovery is going to see the fork as owned by the swapped inode,
2046	 * not the pre-swapped inodes.
2047	 */
2048	src_log_flags = XFS_ILOG_CORE;
2049	target_log_flags = XFS_ILOG_CORE;
2050
2051	if (xfs_sb_version_hasrmapbt(&mp->m_sb))
2052		error = xfs_swap_extent_rmap(&tp, ip, tip);
2053	else
2054		error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags,
2055				&target_log_flags);
2056	if (error)
2057		goto out_trans_cancel;
2058
2059	/* Do we have to swap reflink flags? */
2060	if ((ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK) ^
2061	    (tip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK)) {
2062		f = ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
2063		ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
2064		ip->i_d.di_flags2 |= tip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
2065		tip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
2066		tip->i_d.di_flags2 |= f & XFS_DIFLAG2_REFLINK;
2067		cowfp = ip->i_cowfp;
2068		ip->i_cowfp = tip->i_cowfp;
2069		tip->i_cowfp = cowfp;
2070		xfs_inode_set_cowblocks_tag(ip);
2071		xfs_inode_set_cowblocks_tag(tip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2072	}
2073
2074	xfs_trans_log_inode(tp, ip,  src_log_flags);
2075	xfs_trans_log_inode(tp, tip, target_log_flags);
2076
2077	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2078	 * If this is a synchronous mount, make sure that the
2079	 * transaction goes to disk before returning to the user.
2080	 */
2081	if (mp->m_flags & XFS_MOUNT_WSYNC)
2082		xfs_trans_set_sync(tp);
2083
2084	error = xfs_trans_commit(tp);
2085
2086	trace_xfs_swap_extent_after(ip, 0);
2087	trace_xfs_swap_extent_after(tip, 1);
2088
 
 
 
2089out_unlock:
2090	xfs_iunlock(ip, lock_flags);
2091	xfs_iunlock(tip, lock_flags);
2092	unlock_two_nondirectories(VFS_I(ip), VFS_I(tip));
2093	return error;
2094
2095out_trans_cancel:
2096	xfs_trans_cancel(tp);
2097	goto out_unlock;
2098}