1/*
   2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   3 * All Rights Reserved.
   4 *
   5 * This program is free software; you can redistribute it and/or
   6 * modify it under the terms of the GNU General Public License as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it would be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, write the Free Software Foundation,
  16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18
  19#include "xfs.h"
  20#include "xfs_fs.h"
  21#include "xfs_types.h"
  22#include "xfs_bit.h"
  23#include "xfs_log.h"
  24#include "xfs_inum.h"
  25#include "xfs_trans.h"
  26#include "xfs_sb.h"
  27#include "xfs_ag.h"
  28#include "xfs_dir2.h"
  29#include "xfs_mount.h"
  30#include "xfs_da_btree.h"
  31#include "xfs_bmap_btree.h"
  32#include "xfs_ialloc_btree.h"
  33#include "xfs_dinode.h"
  34#include "xfs_inode.h"
  35#include "xfs_inode_item.h"
  36#include "xfs_itable.h"
  37#include "xfs_ialloc.h"
  38#include "xfs_alloc.h"
  39#include "xfs_bmap.h"
  40#include "xfs_acl.h"
  41#include "xfs_attr.h"
  42#include "xfs_rw.h"
  43#include "xfs_error.h"
  44#include "xfs_quota.h"
  45#include "xfs_utils.h"
  46#include "xfs_rtalloc.h"
  47#include "xfs_trans_space.h"
  48#include "xfs_log_priv.h"
  49#include "xfs_filestream.h"
  50#include "xfs_vnodeops.h"
  51#include "xfs_trace.h"
  52
  53/*
  54 * The maximum pathlen is 1024 bytes. Since the minimum file system
  55 * blocksize is 512 bytes, we can get a max of 2 extents back from
  56 * bmapi.
  57 */
  58#define SYMLINK_MAPS 2
  59
  60STATIC int
  61xfs_readlink_bmap(
  62	xfs_inode_t	*ip,
  63	char		*link)
  64{
  65	xfs_mount_t	*mp = ip->i_mount;
  66	int		pathlen = ip->i_d.di_size;
  67	int             nmaps = SYMLINK_MAPS;
  68	xfs_bmbt_irec_t mval[SYMLINK_MAPS];
  69	xfs_daddr_t	d;
  70	int		byte_cnt;
  71	int		n;
  72	xfs_buf_t	*bp;
  73	int		error = 0;
  74
  75	error = xfs_bmapi(NULL, ip, 0, XFS_B_TO_FSB(mp, pathlen), 0, NULL, 0,
  76			mval, &nmaps, NULL);
  77	if (error)
  78		goto out;
  79
  80	for (n = 0; n < nmaps; n++) {
  81		d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
  82		byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
  83
  84		bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt),
  85				  XBF_LOCK | XBF_MAPPED | XBF_DONT_BLOCK);
  86		if (!bp)
  87			return XFS_ERROR(ENOMEM);
  88		error = bp->b_error;
  89		if (error) {
  90			xfs_ioerror_alert("xfs_readlink",
  91				  ip->i_mount, bp, XFS_BUF_ADDR(bp));
  92			xfs_buf_relse(bp);
  93			goto out;
  94		}
  95		if (pathlen < byte_cnt)
  96			byte_cnt = pathlen;
  97		pathlen -= byte_cnt;
  98
  99		memcpy(link, bp->b_addr, byte_cnt);
 100		xfs_buf_relse(bp);
 101	}
 102
 103	link[ip->i_d.di_size] = '\0';
 104	error = 0;
 105
 106 out:
 107	return error;
 108}
 109
 110int
 111xfs_readlink(
 112	xfs_inode_t     *ip,
 113	char		*link)
 114{
 115	xfs_mount_t	*mp = ip->i_mount;
 116	int		pathlen;
 117	int		error = 0;
 118
 119	trace_xfs_readlink(ip);
 120
 121	if (XFS_FORCED_SHUTDOWN(mp))
 122		return XFS_ERROR(EIO);
 123
 124	xfs_ilock(ip, XFS_ILOCK_SHARED);
 125
 126	ASSERT(S_ISLNK(ip->i_d.di_mode));
 127	ASSERT(ip->i_d.di_size <= MAXPATHLEN);
 128
 129	pathlen = ip->i_d.di_size;
 130	if (!pathlen)
 131		goto out;
 132
 
 
 
 
 
 
 
 
 
 
 133	if (ip->i_df.if_flags & XFS_IFINLINE) {
 134		memcpy(link, ip->i_df.if_u1.if_data, pathlen);
 135		link[pathlen] = '\0';
 136	} else {
 137		error = xfs_readlink_bmap(ip, link);
 138	}
 139
 140 out:
 141	xfs_iunlock(ip, XFS_ILOCK_SHARED);
 142	return error;
 143}
 144
 145/*
 146 * Flags for xfs_free_eofblocks
 147 */
 148#define XFS_FREE_EOF_TRYLOCK	(1<<0)
 149
 150/*
 151 * This is called by xfs_inactive to free any blocks beyond eof
 152 * when the link count isn't zero and by xfs_dm_punch_hole() when
 153 * punching a hole to EOF.
 154 */
 155STATIC int
 156xfs_free_eofblocks(
 157	xfs_mount_t	*mp,
 158	xfs_inode_t	*ip,
 159	int		flags)
 160{
 161	xfs_trans_t	*tp;
 162	int		error;
 163	xfs_fileoff_t	end_fsb;
 164	xfs_fileoff_t	last_fsb;
 165	xfs_filblks_t	map_len;
 166	int		nimaps;
 167	xfs_bmbt_irec_t	imap;
 168
 169	/*
 170	 * Figure out if there are any blocks beyond the end
 171	 * of the file.  If not, then there is nothing to do.
 172	 */
 173	end_fsb = XFS_B_TO_FSB(mp, ((xfs_ufsize_t)ip->i_size));
 174	last_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
 175	if (last_fsb <= end_fsb)
 176		return 0;
 177	map_len = last_fsb - end_fsb;
 178
 179	nimaps = 1;
 180	xfs_ilock(ip, XFS_ILOCK_SHARED);
 181	error = xfs_bmapi(NULL, ip, end_fsb, map_len, 0,
 182			  NULL, 0, &imap, &nimaps, NULL);
 183	xfs_iunlock(ip, XFS_ILOCK_SHARED);
 184
 185	if (!error && (nimaps != 0) &&
 186	    (imap.br_startblock != HOLESTARTBLOCK ||
 187	     ip->i_delayed_blks)) {
 188		/*
 189		 * Attach the dquots to the inode up front.
 190		 */
 191		error = xfs_qm_dqattach(ip, 0);
 192		if (error)
 193			return error;
 194
 195		/*
 196		 * There are blocks after the end of file.
 197		 * Free them up now by truncating the file to
 198		 * its current size.
 199		 */
 200		tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
 201
 202		if (flags & XFS_FREE_EOF_TRYLOCK) {
 203			if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
 204				xfs_trans_cancel(tp, 0);
 205				return 0;
 206			}
 207		} else {
 208			xfs_ilock(ip, XFS_IOLOCK_EXCL);
 209		}
 210
 211		error = xfs_trans_reserve(tp, 0,
 212					  XFS_ITRUNCATE_LOG_RES(mp),
 213					  0, XFS_TRANS_PERM_LOG_RES,
 214					  XFS_ITRUNCATE_LOG_COUNT);
 215		if (error) {
 216			ASSERT(XFS_FORCED_SHUTDOWN(mp));
 217			xfs_trans_cancel(tp, 0);
 218			xfs_iunlock(ip, XFS_IOLOCK_EXCL);
 219			return error;
 220		}
 221
 222		xfs_ilock(ip, XFS_ILOCK_EXCL);
 223		xfs_trans_ijoin(tp, ip);
 224
 225		error = xfs_itruncate_data(&tp, ip, ip->i_size);
 
 
 
 
 
 
 
 226		if (error) {
 227			/*
 228			 * If we get an error at this point we simply don't
 229			 * bother truncating the file.
 230			 */
 231			xfs_trans_cancel(tp,
 232					 (XFS_TRANS_RELEASE_LOG_RES |
 233					  XFS_TRANS_ABORT));
 234		} else {
 235			error = xfs_trans_commit(tp,
 236						XFS_TRANS_RELEASE_LOG_RES);
 237		}
 238		xfs_iunlock(ip, XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL);
 239	}
 240	return error;
 241}
 242
 243/*
 244 * Free a symlink that has blocks associated with it.
 245 */
 246STATIC int
 247xfs_inactive_symlink_rmt(
 248	xfs_inode_t	*ip,
 249	xfs_trans_t	**tpp)
 250{
 251	xfs_buf_t	*bp;
 252	int		committed;
 253	int		done;
 254	int		error;
 255	xfs_fsblock_t	first_block;
 256	xfs_bmap_free_t	free_list;
 257	int		i;
 258	xfs_mount_t	*mp;
 259	xfs_bmbt_irec_t	mval[SYMLINK_MAPS];
 260	int		nmaps;
 261	xfs_trans_t	*ntp;
 262	int		size;
 263	xfs_trans_t	*tp;
 264
 265	tp = *tpp;
 266	mp = ip->i_mount;
 267	ASSERT(ip->i_d.di_size > XFS_IFORK_DSIZE(ip));
 268	/*
 269	 * We're freeing a symlink that has some
 270	 * blocks allocated to it.  Free the
 271	 * blocks here.  We know that we've got
 272	 * either 1 or 2 extents and that we can
 273	 * free them all in one bunmapi call.
 274	 */
 275	ASSERT(ip->i_d.di_nextents > 0 && ip->i_d.di_nextents <= 2);
 276	if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0,
 277			XFS_TRANS_PERM_LOG_RES, XFS_ITRUNCATE_LOG_COUNT))) {
 278		ASSERT(XFS_FORCED_SHUTDOWN(mp));
 279		xfs_trans_cancel(tp, 0);
 280		*tpp = NULL;
 281		return error;
 282	}
 283	/*
 284	 * Lock the inode, fix the size, and join it to the transaction.
 285	 * Hold it so in the normal path, we still have it locked for
 286	 * the second transaction.  In the error paths we need it
 287	 * held so the cancel won't rele it, see below.
 288	 */
 289	xfs_ilock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 290	size = (int)ip->i_d.di_size;
 291	ip->i_d.di_size = 0;
 292	xfs_trans_ijoin(tp, ip);
 293	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 294	/*
 295	 * Find the block(s) so we can inval and unmap them.
 296	 */
 297	done = 0;
 298	xfs_bmap_init(&free_list, &first_block);
 299	nmaps = ARRAY_SIZE(mval);
 300	if ((error = xfs_bmapi(tp, ip, 0, XFS_B_TO_FSB(mp, size),
 301			XFS_BMAPI_METADATA, &first_block, 0, mval, &nmaps,
 302			&free_list)))
 303		goto error0;
 304	/*
 305	 * Invalidate the block(s).
 306	 */
 307	for (i = 0; i < nmaps; i++) {
 308		bp = xfs_trans_get_buf(tp, mp->m_ddev_targp,
 309			XFS_FSB_TO_DADDR(mp, mval[i].br_startblock),
 310			XFS_FSB_TO_BB(mp, mval[i].br_blockcount), 0);
 
 
 
 
 311		xfs_trans_binval(tp, bp);
 312	}
 313	/*
 314	 * Unmap the dead block(s) to the free_list.
 315	 */
 316	if ((error = xfs_bunmapi(tp, ip, 0, size, XFS_BMAPI_METADATA, nmaps,
 317			&first_block, &free_list, &done)))
 318		goto error1;
 319	ASSERT(done);
 320	/*
 321	 * Commit the first transaction.  This logs the EFI and the inode.
 322	 */
 323	if ((error = xfs_bmap_finish(&tp, &free_list, &committed)))
 324		goto error1;
 325	/*
 326	 * The transaction must have been committed, since there were
 327	 * actually extents freed by xfs_bunmapi.  See xfs_bmap_finish.
 328	 * The new tp has the extent freeing and EFDs.
 329	 */
 330	ASSERT(committed);
 331	/*
 332	 * The first xact was committed, so add the inode to the new one.
 333	 * Mark it dirty so it will be logged and moved forward in the log as
 334	 * part of every commit.
 335	 */
 336	xfs_trans_ijoin(tp, ip);
 337	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 338	/*
 339	 * Get a new, empty transaction to return to our caller.
 340	 */
 341	ntp = xfs_trans_dup(tp);
 342	/*
 343	 * Commit the transaction containing extent freeing and EFDs.
 344	 * If we get an error on the commit here or on the reserve below,
 345	 * we need to unlock the inode since the new transaction doesn't
 346	 * have the inode attached.
 347	 */
 348	error = xfs_trans_commit(tp, 0);
 349	tp = ntp;
 350	if (error) {
 351		ASSERT(XFS_FORCED_SHUTDOWN(mp));
 352		goto error0;
 353	}
 354	/*
 355	 * transaction commit worked ok so we can drop the extra ticket
 356	 * reference that we gained in xfs_trans_dup()
 357	 */
 358	xfs_log_ticket_put(tp->t_ticket);
 359
 360	/*
 361	 * Remove the memory for extent descriptions (just bookkeeping).
 362	 */
 363	if (ip->i_df.if_bytes)
 364		xfs_idata_realloc(ip, -ip->i_df.if_bytes, XFS_DATA_FORK);
 365	ASSERT(ip->i_df.if_bytes == 0);
 366	/*
 367	 * Put an itruncate log reservation in the new transaction
 368	 * for our caller.
 369	 */
 370	if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0,
 371			XFS_TRANS_PERM_LOG_RES, XFS_ITRUNCATE_LOG_COUNT))) {
 372		ASSERT(XFS_FORCED_SHUTDOWN(mp));
 373		goto error0;
 374	}
 375	/*
 376	 * Return with the inode locked but not joined to the transaction.
 377	 */
 378	*tpp = tp;
 379	return 0;
 380
 381 error1:
 382	xfs_bmap_cancel(&free_list);
 383 error0:
 384	/*
 385	 * Have to come here with the inode locked and either
 386	 * (held and in the transaction) or (not in the transaction).
 387	 * If the inode isn't held then cancel would iput it, but
 388	 * that's wrong since this is inactive and the vnode ref
 389	 * count is 0 already.
 390	 * Cancel won't do anything to the inode if held, but it still
 391	 * needs to be locked until the cancel is done, if it was
 392	 * joined to the transaction.
 393	 */
 394	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 395	xfs_iunlock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 396	*tpp = NULL;
 397	return error;
 398
 399}
 400
 401STATIC int
 402xfs_inactive_symlink_local(
 403	xfs_inode_t	*ip,
 404	xfs_trans_t	**tpp)
 405{
 406	int		error;
 407
 408	ASSERT(ip->i_d.di_size <= XFS_IFORK_DSIZE(ip));
 409	/*
 410	 * We're freeing a symlink which fit into
 411	 * the inode.  Just free the memory used
 412	 * to hold the old symlink.
 413	 */
 414	error = xfs_trans_reserve(*tpp, 0,
 415				  XFS_ITRUNCATE_LOG_RES(ip->i_mount),
 416				  0, XFS_TRANS_PERM_LOG_RES,
 417				  XFS_ITRUNCATE_LOG_COUNT);
 418
 419	if (error) {
 420		xfs_trans_cancel(*tpp, 0);
 421		*tpp = NULL;
 422		return error;
 423	}
 424	xfs_ilock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
 425
 426	/*
 427	 * Zero length symlinks _can_ exist.
 428	 */
 429	if (ip->i_df.if_bytes > 0) {
 430		xfs_idata_realloc(ip,
 431				  -(ip->i_df.if_bytes),
 432				  XFS_DATA_FORK);
 433		ASSERT(ip->i_df.if_bytes == 0);
 434	}
 435	return 0;
 436}
 437
 438STATIC int
 439xfs_inactive_attrs(
 440	xfs_inode_t	*ip,
 441	xfs_trans_t	**tpp)
 442{
 443	xfs_trans_t	*tp;
 444	int		error;
 445	xfs_mount_t	*mp;
 446
 447	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
 448	tp = *tpp;
 449	mp = ip->i_mount;
 450	ASSERT(ip->i_d.di_forkoff != 0);
 451	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
 452	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 453	if (error)
 454		goto error_unlock;
 455
 456	error = xfs_attr_inactive(ip);
 457	if (error)
 458		goto error_unlock;
 459
 460	tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
 461	error = xfs_trans_reserve(tp, 0,
 462				  XFS_IFREE_LOG_RES(mp),
 463				  0, XFS_TRANS_PERM_LOG_RES,
 464				  XFS_INACTIVE_LOG_COUNT);
 465	if (error)
 466		goto error_cancel;
 467
 468	xfs_ilock(ip, XFS_ILOCK_EXCL);
 469	xfs_trans_ijoin(tp, ip);
 470	xfs_idestroy_fork(ip, XFS_ATTR_FORK);
 471
 472	ASSERT(ip->i_d.di_anextents == 0);
 473
 474	*tpp = tp;
 475	return 0;
 476
 477error_cancel:
 478	ASSERT(XFS_FORCED_SHUTDOWN(mp));
 479	xfs_trans_cancel(tp, 0);
 480error_unlock:
 481	*tpp = NULL;
 482	xfs_iunlock(ip, XFS_IOLOCK_EXCL);
 483	return error;
 484}
 485
 486int
 487xfs_release(
 488	xfs_inode_t	*ip)
 489{
 490	xfs_mount_t	*mp = ip->i_mount;
 491	int		error;
 492
 493	if (!S_ISREG(ip->i_d.di_mode) || (ip->i_d.di_mode == 0))
 494		return 0;
 495
 496	/* If this is a read-only mount, don't do this (would generate I/O) */
 497	if (mp->m_flags & XFS_MOUNT_RDONLY)
 498		return 0;
 499
 500	if (!XFS_FORCED_SHUTDOWN(mp)) {
 501		int truncated;
 502
 503		/*
 504		 * If we are using filestreams, and we have an unlinked
 505		 * file that we are processing the last close on, then nothing
 506		 * will be able to reopen and write to this file. Purge this
 507		 * inode from the filestreams cache so that it doesn't delay
 508		 * teardown of the inode.
 509		 */
 510		if ((ip->i_d.di_nlink == 0) && xfs_inode_is_filestream(ip))
 511			xfs_filestream_deassociate(ip);
 512
 513		/*
 514		 * If we previously truncated this file and removed old data
 515		 * in the process, we want to initiate "early" writeout on
 516		 * the last close.  This is an attempt to combat the notorious
 517		 * NULL files problem which is particularly noticeable from a
 518		 * truncate down, buffered (re-)write (delalloc), followed by
 519		 * a crash.  What we are effectively doing here is
 520		 * significantly reducing the time window where we'd otherwise
 521		 * be exposed to that problem.
 522		 */
 523		truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
 524		if (truncated) {
 525			xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
 526			if (VN_DIRTY(VFS_I(ip)) && ip->i_delayed_blks > 0)
 527				xfs_flush_pages(ip, 0, -1, XBF_ASYNC, FI_NONE);
 528		}
 529	}
 530
 531	if (ip->i_d.di_nlink == 0)
 532		return 0;
 533
 534	if ((S_ISREG(ip->i_d.di_mode) &&
 535	     ((ip->i_size > 0) || (VN_CACHED(VFS_I(ip)) > 0 ||
 536	       ip->i_delayed_blks > 0)) &&
 537	     (ip->i_df.if_flags & XFS_IFEXTENTS))  &&
 538	    (!(ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)))) {
 539
 540		/*
 541		 * If we can't get the iolock just skip truncating the blocks
 542		 * past EOF because we could deadlock with the mmap_sem
 543		 * otherwise.  We'll get another chance to drop them once the
 544		 * last reference to the inode is dropped, so we'll never leak
 545		 * blocks permanently.
 546		 *
 547		 * Further, check if the inode is being opened, written and
 548		 * closed frequently and we have delayed allocation blocks
 549		 * outstanding (e.g. streaming writes from the NFS server),
 550		 * truncating the blocks past EOF will cause fragmentation to
 551		 * occur.
 552		 *
 553		 * In this case don't do the truncation, either, but we have to
 554		 * be careful how we detect this case. Blocks beyond EOF show
 555		 * up as i_delayed_blks even when the inode is clean, so we
 556		 * need to truncate them away first before checking for a dirty
 557		 * release. Hence on the first dirty close we will still remove
 558		 * the speculative allocation, but after that we will leave it
 559		 * in place.
 560		 */
 561		if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
 562			return 0;
 563
 564		error = xfs_free_eofblocks(mp, ip,
 565					   XFS_FREE_EOF_TRYLOCK);
 566		if (error)
 567			return error;
 568
 569		/* delalloc blocks after truncation means it really is dirty */
 570		if (ip->i_delayed_blks)
 571			xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
 572	}
 573	return 0;
 574}
 575
 576/*
 577 * xfs_inactive
 578 *
 579 * This is called when the vnode reference count for the vnode
 580 * goes to zero.  If the file has been unlinked, then it must
 581 * now be truncated.  Also, we clear all of the read-ahead state
 582 * kept for the inode here since the file is now closed.
 583 */
 584int
 585xfs_inactive(
 586	xfs_inode_t	*ip)
 587{
 588	xfs_bmap_free_t	free_list;
 589	xfs_fsblock_t	first_block;
 590	int		committed;
 591	xfs_trans_t	*tp;
 592	xfs_mount_t	*mp;
 593	int		error;
 594	int		truncate;
 595
 596	/*
 597	 * If the inode is already free, then there can be nothing
 598	 * to clean up here.
 599	 */
 600	if (ip->i_d.di_mode == 0 || is_bad_inode(VFS_I(ip))) {
 601		ASSERT(ip->i_df.if_real_bytes == 0);
 602		ASSERT(ip->i_df.if_broot_bytes == 0);
 603		return VN_INACTIVE_CACHE;
 604	}
 605
 606	/*
 607	 * Only do a truncate if it's a regular file with
 608	 * some actual space in it.  It's OK to look at the
 609	 * inode's fields without the lock because we're the
 610	 * only one with a reference to the inode.
 611	 */
 612	truncate = ((ip->i_d.di_nlink == 0) &&
 613	    ((ip->i_d.di_size != 0) || (ip->i_size != 0) ||
 614	     (ip->i_d.di_nextents > 0) || (ip->i_delayed_blks > 0)) &&
 615	    S_ISREG(ip->i_d.di_mode));
 616
 617	mp = ip->i_mount;
 618
 619	error = 0;
 620
 621	/* If this is a read-only mount, don't do this (would generate I/O) */
 622	if (mp->m_flags & XFS_MOUNT_RDONLY)
 623		goto out;
 624
 625	if (ip->i_d.di_nlink != 0) {
 626		if ((S_ISREG(ip->i_d.di_mode) &&
 627                     ((ip->i_size > 0) || (VN_CACHED(VFS_I(ip)) > 0 ||
 628                       ip->i_delayed_blks > 0)) &&
 629		      (ip->i_df.if_flags & XFS_IFEXTENTS) &&
 630		     (!(ip->i_d.di_flags &
 631				(XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)) ||
 632		      (ip->i_delayed_blks != 0)))) {
 633			error = xfs_free_eofblocks(mp, ip, 0);
 634			if (error)
 635				return VN_INACTIVE_CACHE;
 636		}
 637		goto out;
 638	}
 639
 640	ASSERT(ip->i_d.di_nlink == 0);
 641
 642	error = xfs_qm_dqattach(ip, 0);
 643	if (error)
 644		return VN_INACTIVE_CACHE;
 645
 646	tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
 647	if (truncate) {
 648		xfs_ilock(ip, XFS_IOLOCK_EXCL);
 649
 650		xfs_ioend_wait(ip);
 651
 652		error = xfs_trans_reserve(tp, 0,
 653					  XFS_ITRUNCATE_LOG_RES(mp),
 654					  0, XFS_TRANS_PERM_LOG_RES,
 655					  XFS_ITRUNCATE_LOG_COUNT);
 656		if (error) {
 657			/* Don't call itruncate_cleanup */
 658			ASSERT(XFS_FORCED_SHUTDOWN(mp));
 659			xfs_trans_cancel(tp, 0);
 660			xfs_iunlock(ip, XFS_IOLOCK_EXCL);
 661			return VN_INACTIVE_CACHE;
 662		}
 663
 664		xfs_ilock(ip, XFS_ILOCK_EXCL);
 665		xfs_trans_ijoin(tp, ip);
 
 
 
 666
 667		error = xfs_itruncate_data(&tp, ip, 0);
 668		if (error) {
 669			xfs_trans_cancel(tp,
 670				XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
 671			xfs_iunlock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 672			return VN_INACTIVE_CACHE;
 673		}
 
 
 674	} else if (S_ISLNK(ip->i_d.di_mode)) {
 675
 676		/*
 677		 * If we get an error while cleaning up a
 678		 * symlink we bail out.
 679		 */
 680		error = (ip->i_d.di_size > XFS_IFORK_DSIZE(ip)) ?
 681			xfs_inactive_symlink_rmt(ip, &tp) :
 682			xfs_inactive_symlink_local(ip, &tp);
 683
 684		if (error) {
 685			ASSERT(tp == NULL);
 686			return VN_INACTIVE_CACHE;
 687		}
 688
 689		xfs_trans_ijoin(tp, ip);
 690	} else {
 691		error = xfs_trans_reserve(tp, 0,
 692					  XFS_IFREE_LOG_RES(mp),
 693					  0, XFS_TRANS_PERM_LOG_RES,
 694					  XFS_INACTIVE_LOG_COUNT);
 695		if (error) {
 696			ASSERT(XFS_FORCED_SHUTDOWN(mp));
 697			xfs_trans_cancel(tp, 0);
 698			return VN_INACTIVE_CACHE;
 699		}
 700
 701		xfs_ilock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
 702		xfs_trans_ijoin(tp, ip);
 703	}
 704
 705	/*
 706	 * If there are attributes associated with the file
 707	 * then blow them away now.  The code calls a routine
 708	 * that recursively deconstructs the attribute fork.
 709	 * We need to just commit the current transaction
 710	 * because we can't use it for xfs_attr_inactive().
 711	 */
 712	if (ip->i_d.di_anextents > 0) {
 713		error = xfs_inactive_attrs(ip, &tp);
 714		/*
 715		 * If we got an error, the transaction is already
 716		 * cancelled, and the inode is unlocked. Just get out.
 717		 */
 718		 if (error)
 719			 return VN_INACTIVE_CACHE;
 720	} else if (ip->i_afp) {
 721		xfs_idestroy_fork(ip, XFS_ATTR_FORK);
 722	}
 723
 724	/*
 725	 * Free the inode.
 726	 */
 727	xfs_bmap_init(&free_list, &first_block);
 728	error = xfs_ifree(tp, ip, &free_list);
 729	if (error) {
 730		/*
 731		 * If we fail to free the inode, shut down.  The cancel
 732		 * might do that, we need to make sure.  Otherwise the
 733		 * inode might be lost for a long time or forever.
 734		 */
 735		if (!XFS_FORCED_SHUTDOWN(mp)) {
 736			xfs_notice(mp, "%s: xfs_ifree returned error %d",
 737				__func__, error);
 738			xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
 739		}
 740		xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
 741	} else {
 742		/*
 743		 * Credit the quota account(s). The inode is gone.
 744		 */
 745		xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
 746
 747		/*
 748		 * Just ignore errors at this point.  There is nothing we can
 749		 * do except to try to keep going. Make sure it's not a silent
 750		 * error.
 751		 */
 752		error = xfs_bmap_finish(&tp,  &free_list, &committed);
 753		if (error)
 754			xfs_notice(mp, "%s: xfs_bmap_finish returned error %d",
 755				__func__, error);
 756		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
 757		if (error)
 758			xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
 759				__func__, error);
 760	}
 761
 762	/*
 763	 * Release the dquots held by inode, if any.
 764	 */
 765	xfs_qm_dqdetach(ip);
 766	xfs_iunlock(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL);
 767
 768 out:
 769	return VN_INACTIVE_CACHE;
 770}
 771
 772/*
 773 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
 774 * is allowed, otherwise it has to be an exact match. If a CI match is found,
 775 * ci_name->name will point to a the actual name (caller must free) or
 776 * will be set to NULL if an exact match is found.
 777 */
 778int
 779xfs_lookup(
 780	xfs_inode_t		*dp,
 781	struct xfs_name		*name,
 782	xfs_inode_t		**ipp,
 783	struct xfs_name		*ci_name)
 784{
 785	xfs_ino_t		inum;
 786	int			error;
 787	uint			lock_mode;
 788
 789	trace_xfs_lookup(dp, name);
 790
 791	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
 792		return XFS_ERROR(EIO);
 793
 794	lock_mode = xfs_ilock_map_shared(dp);
 795	error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
 796	xfs_iunlock_map_shared(dp, lock_mode);
 797
 798	if (error)
 799		goto out;
 800
 801	error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
 802	if (error)
 803		goto out_free_name;
 804
 805	return 0;
 806
 807out_free_name:
 808	if (ci_name)
 809		kmem_free(ci_name->name);
 810out:
 811	*ipp = NULL;
 812	return error;
 813}
 814
 815int
 816xfs_create(
 817	xfs_inode_t		*dp,
 818	struct xfs_name		*name,
 819	mode_t			mode,
 820	xfs_dev_t		rdev,
 821	xfs_inode_t		**ipp)
 822{
 823	int			is_dir = S_ISDIR(mode);
 824	struct xfs_mount	*mp = dp->i_mount;
 825	struct xfs_inode	*ip = NULL;
 826	struct xfs_trans	*tp = NULL;
 827	int			error;
 828	xfs_bmap_free_t		free_list;
 829	xfs_fsblock_t		first_block;
 830	boolean_t		unlock_dp_on_error = B_FALSE;
 831	uint			cancel_flags;
 832	int			committed;
 833	prid_t			prid;
 834	struct xfs_dquot	*udqp = NULL;
 835	struct xfs_dquot	*gdqp = NULL;
 836	uint			resblks;
 837	uint			log_res;
 838	uint			log_count;
 839
 840	trace_xfs_create(dp, name);
 841
 842	if (XFS_FORCED_SHUTDOWN(mp))
 843		return XFS_ERROR(EIO);
 844
 845	if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
 846		prid = xfs_get_projid(dp);
 847	else
 848		prid = XFS_PROJID_DEFAULT;
 849
 850	/*
 851	 * Make sure that we have allocated dquot(s) on disk.
 852	 */
 853	error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid,
 854			XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp);
 855	if (error)
 856		return error;
 857
 858	if (is_dir) {
 859		rdev = 0;
 860		resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
 861		log_res = XFS_MKDIR_LOG_RES(mp);
 862		log_count = XFS_MKDIR_LOG_COUNT;
 863		tp = xfs_trans_alloc(mp, XFS_TRANS_MKDIR);
 864	} else {
 865		resblks = XFS_CREATE_SPACE_RES(mp, name->len);
 866		log_res = XFS_CREATE_LOG_RES(mp);
 867		log_count = XFS_CREATE_LOG_COUNT;
 868		tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE);
 869	}
 870
 871	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
 872
 873	/*
 874	 * Initially assume that the file does not exist and
 875	 * reserve the resources for that case.  If that is not
 876	 * the case we'll drop the one we have and get a more
 877	 * appropriate transaction later.
 878	 */
 879	error = xfs_trans_reserve(tp, resblks, log_res, 0,
 880			XFS_TRANS_PERM_LOG_RES, log_count);
 881	if (error == ENOSPC) {
 882		/* flush outstanding delalloc blocks and retry */
 883		xfs_flush_inodes(dp);
 884		error = xfs_trans_reserve(tp, resblks, log_res, 0,
 885				XFS_TRANS_PERM_LOG_RES, log_count);
 886	}
 887	if (error == ENOSPC) {
 888		/* No space at all so try a "no-allocation" reservation */
 889		resblks = 0;
 890		error = xfs_trans_reserve(tp, 0, log_res, 0,
 891				XFS_TRANS_PERM_LOG_RES, log_count);
 892	}
 893	if (error) {
 894		cancel_flags = 0;
 895		goto out_trans_cancel;
 896	}
 897
 898	xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
 899	unlock_dp_on_error = B_TRUE;
 900
 901	/*
 902	 * Check for directory link count overflow.
 903	 */
 904	if (is_dir && dp->i_d.di_nlink >= XFS_MAXLINK) {
 905		error = XFS_ERROR(EMLINK);
 906		goto out_trans_cancel;
 907	}
 908
 909	xfs_bmap_init(&free_list, &first_block);
 910
 911	/*
 912	 * Reserve disk quota and the inode.
 913	 */
 914	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp, resblks, 1, 0);
 915	if (error)
 916		goto out_trans_cancel;
 917
 918	error = xfs_dir_canenter(tp, dp, name, resblks);
 919	if (error)
 920		goto out_trans_cancel;
 921
 922	/*
 923	 * A newly created regular or special file just has one directory
 924	 * entry pointing to them, but a directory also the "." entry
 925	 * pointing to itself.
 926	 */
 927	error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
 928			       prid, resblks > 0, &ip, &committed);
 929	if (error) {
 930		if (error == ENOSPC)
 931			goto out_trans_cancel;
 932		goto out_trans_abort;
 933	}
 934
 935	/*
 936	 * Now we join the directory inode to the transaction.  We do not do it
 937	 * earlier because xfs_dir_ialloc might commit the previous transaction
 938	 * (and release all the locks).  An error from here on will result in
 939	 * the transaction cancel unlocking dp so don't do it explicitly in the
 940	 * error path.
 941	 */
 942	xfs_trans_ijoin_ref(tp, dp, XFS_ILOCK_EXCL);
 943	unlock_dp_on_error = B_FALSE;
 944
 945	error = xfs_dir_createname(tp, dp, name, ip->i_ino,
 946					&first_block, &free_list, resblks ?
 947					resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
 948	if (error) {
 949		ASSERT(error != ENOSPC);
 950		goto out_trans_abort;
 951	}
 952	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
 953	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
 954
 955	if (is_dir) {
 956		error = xfs_dir_init(tp, ip, dp);
 957		if (error)
 958			goto out_bmap_cancel;
 959
 960		error = xfs_bumplink(tp, dp);
 961		if (error)
 962			goto out_bmap_cancel;
 963	}
 964
 965	/*
 966	 * If this is a synchronous mount, make sure that the
 967	 * create transaction goes to disk before returning to
 968	 * the user.
 969	 */
 970	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
 971		xfs_trans_set_sync(tp);
 972
 973	/*
 974	 * Attach the dquot(s) to the inodes and modify them incore.
 975	 * These ids of the inode couldn't have changed since the new
 976	 * inode has been locked ever since it was created.
 977	 */
 978	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp);
 979
 980	error = xfs_bmap_finish(&tp, &free_list, &committed);
 981	if (error)
 982		goto out_bmap_cancel;
 983
 984	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
 985	if (error)
 986		goto out_release_inode;
 987
 988	xfs_qm_dqrele(udqp);
 989	xfs_qm_dqrele(gdqp);
 990
 991	*ipp = ip;
 992	return 0;
 993
 994 out_bmap_cancel:
 995	xfs_bmap_cancel(&free_list);
 996 out_trans_abort:
 997	cancel_flags |= XFS_TRANS_ABORT;
 998 out_trans_cancel:
 999	xfs_trans_cancel(tp, cancel_flags);
1000 out_release_inode:
1001	/*
1002	 * Wait until after the current transaction is aborted to
1003	 * release the inode.  This prevents recursive transactions
1004	 * and deadlocks from xfs_inactive.
1005	 */
1006	if (ip)
1007		IRELE(ip);
1008
1009	xfs_qm_dqrele(udqp);
1010	xfs_qm_dqrele(gdqp);
1011
1012	if (unlock_dp_on_error)
1013		xfs_iunlock(dp, XFS_ILOCK_EXCL);
1014	return error;
1015}
1016
1017#ifdef DEBUG
1018int xfs_locked_n;
1019int xfs_small_retries;
1020int xfs_middle_retries;
1021int xfs_lots_retries;
1022int xfs_lock_delays;
1023#endif
1024
1025/*
1026 * Bump the subclass so xfs_lock_inodes() acquires each lock with
1027 * a different value
1028 */
1029static inline int
1030xfs_lock_inumorder(int lock_mode, int subclass)
1031{
1032	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
1033		lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT;
1034	if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))
1035		lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT;
1036
1037	return lock_mode;
1038}
1039
1040/*
1041 * The following routine will lock n inodes in exclusive mode.
1042 * We assume the caller calls us with the inodes in i_ino order.
1043 *
1044 * We need to detect deadlock where an inode that we lock
1045 * is in the AIL and we start waiting for another inode that is locked
1046 * by a thread in a long running transaction (such as truncate). This can
1047 * result in deadlock since the long running trans might need to wait
1048 * for the inode we just locked in order to push the tail and free space
1049 * in the log.
1050 */
1051void
1052xfs_lock_inodes(
1053	xfs_inode_t	**ips,
1054	int		inodes,
1055	uint		lock_mode)
1056{
1057	int		attempts = 0, i, j, try_lock;
1058	xfs_log_item_t	*lp;
1059
1060	ASSERT(ips && (inodes >= 2)); /* we need at least two */
1061
1062	try_lock = 0;
1063	i = 0;
1064
1065again:
1066	for (; i < inodes; i++) {
1067		ASSERT(ips[i]);
1068
1069		if (i && (ips[i] == ips[i-1]))	/* Already locked */
1070			continue;
1071
1072		/*
1073		 * If try_lock is not set yet, make sure all locked inodes
1074		 * are not in the AIL.
1075		 * If any are, set try_lock to be used later.
1076		 */
1077
1078		if (!try_lock) {
1079			for (j = (i - 1); j >= 0 && !try_lock; j--) {
1080				lp = (xfs_log_item_t *)ips[j]->i_itemp;
1081				if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
1082					try_lock++;
1083				}
1084			}
1085		}
1086
1087		/*
1088		 * If any of the previous locks we have locked is in the AIL,
1089		 * we must TRY to get the second and subsequent locks. If
1090		 * we can't get any, we must release all we have
1091		 * and try again.
1092		 */
1093
1094		if (try_lock) {
1095			/* try_lock must be 0 if i is 0. */
1096			/*
1097			 * try_lock means we have an inode locked
1098			 * that is in the AIL.
1099			 */
1100			ASSERT(i != 0);
1101			if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) {
1102				attempts++;
1103
1104				/*
1105				 * Unlock all previous guys and try again.
1106				 * xfs_iunlock will try to push the tail
1107				 * if the inode is in the AIL.
1108				 */
1109
1110				for(j = i - 1; j >= 0; j--) {
1111
1112					/*
1113					 * Check to see if we've already
1114					 * unlocked this one.
1115					 * Not the first one going back,
1116					 * and the inode ptr is the same.
1117					 */
1118					if ((j != (i - 1)) && ips[j] ==
1119								ips[j+1])
1120						continue;
1121
1122					xfs_iunlock(ips[j], lock_mode);
1123				}
1124
1125				if ((attempts % 5) == 0) {
1126					delay(1); /* Don't just spin the CPU */
1127#ifdef DEBUG
1128					xfs_lock_delays++;
1129#endif
1130				}
1131				i = 0;
1132				try_lock = 0;
1133				goto again;
1134			}
1135		} else {
1136			xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
1137		}
1138	}
1139
1140#ifdef DEBUG
1141	if (attempts) {
1142		if (attempts < 5) xfs_small_retries++;
1143		else if (attempts < 100) xfs_middle_retries++;
1144		else xfs_lots_retries++;
1145	} else {
1146		xfs_locked_n++;
1147	}
1148#endif
1149}
1150
1151/*
1152 * xfs_lock_two_inodes() can only be used to lock one type of lock
1153 * at a time - the iolock or the ilock, but not both at once. If
1154 * we lock both at once, lockdep will report false positives saying
1155 * we have violated locking orders.
1156 */
1157void
1158xfs_lock_two_inodes(
1159	xfs_inode_t		*ip0,
1160	xfs_inode_t		*ip1,
1161	uint			lock_mode)
1162{
1163	xfs_inode_t		*temp;
1164	int			attempts = 0;
1165	xfs_log_item_t		*lp;
1166
1167	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
1168		ASSERT((lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) == 0);
1169	ASSERT(ip0->i_ino != ip1->i_ino);
1170
1171	if (ip0->i_ino > ip1->i_ino) {
1172		temp = ip0;
1173		ip0 = ip1;
1174		ip1 = temp;
1175	}
1176
1177 again:
1178	xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0));
1179
1180	/*
1181	 * If the first lock we have locked is in the AIL, we must TRY to get
1182	 * the second lock. If we can't get it, we must release the first one
1183	 * and try again.
1184	 */
1185	lp = (xfs_log_item_t *)ip0->i_itemp;
1186	if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
1187		if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) {
1188			xfs_iunlock(ip0, lock_mode);
1189			if ((++attempts % 5) == 0)
1190				delay(1); /* Don't just spin the CPU */
1191			goto again;
1192		}
1193	} else {
1194		xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1));
1195	}
1196}
1197
1198int
1199xfs_remove(
1200	xfs_inode_t             *dp,
1201	struct xfs_name		*name,
1202	xfs_inode_t		*ip)
1203{
1204	xfs_mount_t		*mp = dp->i_mount;
1205	xfs_trans_t             *tp = NULL;
1206	int			is_dir = S_ISDIR(ip->i_d.di_mode);
1207	int                     error = 0;
1208	xfs_bmap_free_t         free_list;
1209	xfs_fsblock_t           first_block;
1210	int			cancel_flags;
1211	int			committed;
1212	int			link_zero;
1213	uint			resblks;
1214	uint			log_count;
1215
1216	trace_xfs_remove(dp, name);
1217
1218	if (XFS_FORCED_SHUTDOWN(mp))
1219		return XFS_ERROR(EIO);
1220
1221	error = xfs_qm_dqattach(dp, 0);
1222	if (error)
1223		goto std_return;
1224
1225	error = xfs_qm_dqattach(ip, 0);
1226	if (error)
1227		goto std_return;
1228
1229	if (is_dir) {
1230		tp = xfs_trans_alloc(mp, XFS_TRANS_RMDIR);
1231		log_count = XFS_DEFAULT_LOG_COUNT;
1232	} else {
1233		tp = xfs_trans_alloc(mp, XFS_TRANS_REMOVE);
1234		log_count = XFS_REMOVE_LOG_COUNT;
1235	}
1236	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1237
1238	/*
1239	 * We try to get the real space reservation first,
1240	 * allowing for directory btree deletion(s) implying
1241	 * possible bmap insert(s).  If we can't get the space
1242	 * reservation then we use 0 instead, and avoid the bmap
1243	 * btree insert(s) in the directory code by, if the bmap
1244	 * insert tries to happen, instead trimming the LAST
1245	 * block from the directory.
1246	 */
1247	resblks = XFS_REMOVE_SPACE_RES(mp);
1248	error = xfs_trans_reserve(tp, resblks, XFS_REMOVE_LOG_RES(mp), 0,
1249				  XFS_TRANS_PERM_LOG_RES, log_count);
1250	if (error == ENOSPC) {
1251		resblks = 0;
1252		error = xfs_trans_reserve(tp, 0, XFS_REMOVE_LOG_RES(mp), 0,
1253					  XFS_TRANS_PERM_LOG_RES, log_count);
1254	}
1255	if (error) {
1256		ASSERT(error != ENOSPC);
1257		cancel_flags = 0;
1258		goto out_trans_cancel;
1259	}
1260
1261	xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
1262
1263	xfs_trans_ijoin_ref(tp, dp, XFS_ILOCK_EXCL);
1264	xfs_trans_ijoin_ref(tp, ip, XFS_ILOCK_EXCL);
1265
1266	/*
1267	 * If we're removing a directory perform some additional validation.
1268	 */
1269	if (is_dir) {
1270		ASSERT(ip->i_d.di_nlink >= 2);
1271		if (ip->i_d.di_nlink != 2) {
1272			error = XFS_ERROR(ENOTEMPTY);
1273			goto out_trans_cancel;
1274		}
1275		if (!xfs_dir_isempty(ip)) {
1276			error = XFS_ERROR(ENOTEMPTY);
1277			goto out_trans_cancel;
1278		}
1279	}
1280
1281	xfs_bmap_init(&free_list, &first_block);
1282	error = xfs_dir_removename(tp, dp, name, ip->i_ino,
1283					&first_block, &free_list, resblks);
1284	if (error) {
1285		ASSERT(error != ENOENT);
1286		goto out_bmap_cancel;
1287	}
1288	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1289
1290	if (is_dir) {
1291		/*
1292		 * Drop the link from ip's "..".
1293		 */
1294		error = xfs_droplink(tp, dp);
1295		if (error)
1296			goto out_bmap_cancel;
1297
1298		/*
1299		 * Drop the "." link from ip to self.
1300		 */
1301		error = xfs_droplink(tp, ip);
1302		if (error)
1303			goto out_bmap_cancel;
1304	} else {
1305		/*
1306		 * When removing a non-directory we need to log the parent
1307		 * inode here.  For a directory this is done implicitly
1308		 * by the xfs_droplink call for the ".." entry.
1309		 */
1310		xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1311	}
1312
1313	/*
1314	 * Drop the link from dp to ip.
1315	 */
1316	error = xfs_droplink(tp, ip);
1317	if (error)
1318		goto out_bmap_cancel;
1319
1320	/*
1321	 * Determine if this is the last link while
1322	 * we are in the transaction.
1323	 */
1324	link_zero = (ip->i_d.di_nlink == 0);
1325
1326	/*
1327	 * If this is a synchronous mount, make sure that the
1328	 * remove transaction goes to disk before returning to
1329	 * the user.
1330	 */
1331	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1332		xfs_trans_set_sync(tp);
1333
1334	error = xfs_bmap_finish(&tp, &free_list, &committed);
1335	if (error)
1336		goto out_bmap_cancel;
1337
1338	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1339	if (error)
1340		goto std_return;
1341
1342	/*
1343	 * If we are using filestreams, kill the stream association.
1344	 * If the file is still open it may get a new one but that
1345	 * will get killed on last close in xfs_close() so we don't
1346	 * have to worry about that.
1347	 */
1348	if (!is_dir && link_zero && xfs_inode_is_filestream(ip))
1349		xfs_filestream_deassociate(ip);
1350
1351	return 0;
1352
1353 out_bmap_cancel:
1354	xfs_bmap_cancel(&free_list);
1355	cancel_flags |= XFS_TRANS_ABORT;
1356 out_trans_cancel:
1357	xfs_trans_cancel(tp, cancel_flags);
1358 std_return:
1359	return error;
1360}
1361
1362int
1363xfs_link(
1364	xfs_inode_t		*tdp,
1365	xfs_inode_t		*sip,
1366	struct xfs_name		*target_name)
1367{
1368	xfs_mount_t		*mp = tdp->i_mount;
1369	xfs_trans_t		*tp;
1370	int			error;
1371	xfs_bmap_free_t         free_list;
1372	xfs_fsblock_t           first_block;
1373	int			cancel_flags;
1374	int			committed;
1375	int			resblks;
1376
1377	trace_xfs_link(tdp, target_name);
1378
1379	ASSERT(!S_ISDIR(sip->i_d.di_mode));
1380
1381	if (XFS_FORCED_SHUTDOWN(mp))
1382		return XFS_ERROR(EIO);
1383
1384	error = xfs_qm_dqattach(sip, 0);
1385	if (error)
1386		goto std_return;
1387
1388	error = xfs_qm_dqattach(tdp, 0);
1389	if (error)
1390		goto std_return;
1391
1392	tp = xfs_trans_alloc(mp, XFS_TRANS_LINK);
1393	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1394	resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1395	error = xfs_trans_reserve(tp, resblks, XFS_LINK_LOG_RES(mp), 0,
1396			XFS_TRANS_PERM_LOG_RES, XFS_LINK_LOG_COUNT);
1397	if (error == ENOSPC) {
1398		resblks = 0;
1399		error = xfs_trans_reserve(tp, 0, XFS_LINK_LOG_RES(mp), 0,
1400				XFS_TRANS_PERM_LOG_RES, XFS_LINK_LOG_COUNT);
1401	}
1402	if (error) {
1403		cancel_flags = 0;
1404		goto error_return;
1405	}
1406
1407	xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
1408
1409	xfs_trans_ijoin_ref(tp, sip, XFS_ILOCK_EXCL);
1410	xfs_trans_ijoin_ref(tp, tdp, XFS_ILOCK_EXCL);
1411
1412	/*
1413	 * If the source has too many links, we can't make any more to it.
1414	 */
1415	if (sip->i_d.di_nlink >= XFS_MAXLINK) {
1416		error = XFS_ERROR(EMLINK);
1417		goto error_return;
1418	}
1419
1420	/*
1421	 * If we are using project inheritance, we only allow hard link
1422	 * creation in our tree when the project IDs are the same; else
1423	 * the tree quota mechanism could be circumvented.
1424	 */
1425	if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1426		     (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1427		error = XFS_ERROR(EXDEV);
1428		goto error_return;
1429	}
1430
1431	error = xfs_dir_canenter(tp, tdp, target_name, resblks);
1432	if (error)
1433		goto error_return;
1434
1435	xfs_bmap_init(&free_list, &first_block);
1436
1437	error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1438					&first_block, &free_list, resblks);
1439	if (error)
1440		goto abort_return;
1441	xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1442	xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1443
1444	error = xfs_bumplink(tp, sip);
1445	if (error)
1446		goto abort_return;
1447
1448	/*
1449	 * If this is a synchronous mount, make sure that the
1450	 * link transaction goes to disk before returning to
1451	 * the user.
1452	 */
1453	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
1454		xfs_trans_set_sync(tp);
1455	}
1456
1457	error = xfs_bmap_finish (&tp, &free_list, &committed);
1458	if (error) {
1459		xfs_bmap_cancel(&free_list);
1460		goto abort_return;
1461	}
1462
1463	return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1464
1465 abort_return:
1466	cancel_flags |= XFS_TRANS_ABORT;
1467 error_return:
1468	xfs_trans_cancel(tp, cancel_flags);
1469 std_return:
1470	return error;
1471}
1472
1473int
1474xfs_symlink(
1475	xfs_inode_t		*dp,
1476	struct xfs_name		*link_name,
1477	const char		*target_path,
1478	mode_t			mode,
1479	xfs_inode_t		**ipp)
1480{
1481	xfs_mount_t		*mp = dp->i_mount;
1482	xfs_trans_t		*tp;
1483	xfs_inode_t		*ip;
1484	int			error;
1485	int			pathlen;
1486	xfs_bmap_free_t		free_list;
1487	xfs_fsblock_t		first_block;
1488	boolean_t		unlock_dp_on_error = B_FALSE;
1489	uint			cancel_flags;
1490	int			committed;
1491	xfs_fileoff_t		first_fsb;
1492	xfs_filblks_t		fs_blocks;
1493	int			nmaps;
1494	xfs_bmbt_irec_t		mval[SYMLINK_MAPS];
1495	xfs_daddr_t		d;
1496	const char		*cur_chunk;
1497	int			byte_cnt;
1498	int			n;
1499	xfs_buf_t		*bp;
1500	prid_t			prid;
1501	struct xfs_dquot	*udqp, *gdqp;
1502	uint			resblks;
1503
1504	*ipp = NULL;
1505	error = 0;
1506	ip = NULL;
1507	tp = NULL;
1508
1509	trace_xfs_symlink(dp, link_name);
1510
1511	if (XFS_FORCED_SHUTDOWN(mp))
1512		return XFS_ERROR(EIO);
1513
1514	/*
1515	 * Check component lengths of the target path name.
1516	 */
1517	pathlen = strlen(target_path);
1518	if (pathlen >= MAXPATHLEN)      /* total string too long */
1519		return XFS_ERROR(ENAMETOOLONG);
1520
1521	udqp = gdqp = NULL;
1522	if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
1523		prid = xfs_get_projid(dp);
1524	else
1525		prid = XFS_PROJID_DEFAULT;
1526
1527	/*
1528	 * Make sure that we have allocated dquot(s) on disk.
1529	 */
1530	error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid,
1531			XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp);
1532	if (error)
1533		goto std_return;
1534
1535	tp = xfs_trans_alloc(mp, XFS_TRANS_SYMLINK);
1536	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1537	/*
1538	 * The symlink will fit into the inode data fork?
1539	 * There can't be any attributes so we get the whole variable part.
1540	 */
1541	if (pathlen <= XFS_LITINO(mp))
1542		fs_blocks = 0;
1543	else
1544		fs_blocks = XFS_B_TO_FSB(mp, pathlen);
1545	resblks = XFS_SYMLINK_SPACE_RES(mp, link_name->len, fs_blocks);
1546	error = xfs_trans_reserve(tp, resblks, XFS_SYMLINK_LOG_RES(mp), 0,
1547			XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT);
1548	if (error == ENOSPC && fs_blocks == 0) {
1549		resblks = 0;
1550		error = xfs_trans_reserve(tp, 0, XFS_SYMLINK_LOG_RES(mp), 0,
1551				XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT);
1552	}
1553	if (error) {
1554		cancel_flags = 0;
1555		goto error_return;
1556	}
1557
1558	xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1559	unlock_dp_on_error = B_TRUE;
1560
1561	/*
1562	 * Check whether the directory allows new symlinks or not.
1563	 */
1564	if (dp->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) {
1565		error = XFS_ERROR(EPERM);
1566		goto error_return;
1567	}
1568
1569	/*
1570	 * Reserve disk quota : blocks and inode.
1571	 */
1572	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp, resblks, 1, 0);
1573	if (error)
1574		goto error_return;
1575
1576	/*
1577	 * Check for ability to enter directory entry, if no space reserved.
1578	 */
1579	error = xfs_dir_canenter(tp, dp, link_name, resblks);
1580	if (error)
1581		goto error_return;
1582	/*
1583	 * Initialize the bmap freelist prior to calling either
1584	 * bmapi or the directory create code.
1585	 */
1586	xfs_bmap_init(&free_list, &first_block);
1587
1588	/*
1589	 * Allocate an inode for the symlink.
1590	 */
1591	error = xfs_dir_ialloc(&tp, dp, S_IFLNK | (mode & ~S_IFMT), 1, 0,
1592			       prid, resblks > 0, &ip, NULL);
1593	if (error) {
1594		if (error == ENOSPC)
1595			goto error_return;
1596		goto error1;
1597	}
1598
1599	/*
1600	 * An error after we've joined dp to the transaction will result in the
1601	 * transaction cancel unlocking dp so don't do it explicitly in the
1602	 * error path.
1603	 */
1604	xfs_trans_ijoin_ref(tp, dp, XFS_ILOCK_EXCL);
1605	unlock_dp_on_error = B_FALSE;
1606
1607	/*
1608	 * Also attach the dquot(s) to it, if applicable.
1609	 */
1610	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp);
1611
1612	if (resblks)
1613		resblks -= XFS_IALLOC_SPACE_RES(mp);
1614	/*
1615	 * If the symlink will fit into the inode, write it inline.
1616	 */
1617	if (pathlen <= XFS_IFORK_DSIZE(ip)) {
1618		xfs_idata_realloc(ip, pathlen, XFS_DATA_FORK);
1619		memcpy(ip->i_df.if_u1.if_data, target_path, pathlen);
1620		ip->i_d.di_size = pathlen;
1621
1622		/*
1623		 * The inode was initially created in extent format.
1624		 */
1625		ip->i_df.if_flags &= ~(XFS_IFEXTENTS | XFS_IFBROOT);
1626		ip->i_df.if_flags |= XFS_IFINLINE;
1627
1628		ip->i_d.di_format = XFS_DINODE_FMT_LOCAL;
1629		xfs_trans_log_inode(tp, ip, XFS_ILOG_DDATA | XFS_ILOG_CORE);
1630
1631	} else {
1632		first_fsb = 0;
1633		nmaps = SYMLINK_MAPS;
1634
1635		error = xfs_bmapi(tp, ip, first_fsb, fs_blocks,
1636				  XFS_BMAPI_WRITE | XFS_BMAPI_METADATA,
1637				  &first_block, resblks, mval, &nmaps,
1638				  &free_list);
1639		if (error)
1640			goto error2;
1641
1642		if (resblks)
1643			resblks -= fs_blocks;
1644		ip->i_d.di_size = pathlen;
1645		xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1646
1647		cur_chunk = target_path;
1648		for (n = 0; n < nmaps; n++) {
1649			d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
1650			byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
1651			bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
1652					       BTOBB(byte_cnt), 0);
1653			ASSERT(!xfs_buf_geterror(bp));
 
 
 
1654			if (pathlen < byte_cnt) {
1655				byte_cnt = pathlen;
1656			}
1657			pathlen -= byte_cnt;
1658
1659			memcpy(bp->b_addr, cur_chunk, byte_cnt);
1660			cur_chunk += byte_cnt;
1661
1662			xfs_trans_log_buf(tp, bp, 0, byte_cnt - 1);
1663		}
1664	}
1665
1666	/*
1667	 * Create the directory entry for the symlink.
1668	 */
1669	error = xfs_dir_createname(tp, dp, link_name, ip->i_ino,
1670					&first_block, &free_list, resblks);
1671	if (error)
1672		goto error2;
1673	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1674	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1675
1676	/*
1677	 * If this is a synchronous mount, make sure that the
1678	 * symlink transaction goes to disk before returning to
1679	 * the user.
1680	 */
1681	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
1682		xfs_trans_set_sync(tp);
1683	}
1684
1685	error = xfs_bmap_finish(&tp, &free_list, &committed);
1686	if (error) {
1687		goto error2;
1688	}
1689	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1690	xfs_qm_dqrele(udqp);
1691	xfs_qm_dqrele(gdqp);
1692
1693	*ipp = ip;
1694	return 0;
1695
1696 error2:
1697	IRELE(ip);
1698 error1:
1699	xfs_bmap_cancel(&free_list);
1700	cancel_flags |= XFS_TRANS_ABORT;
1701 error_return:
1702	xfs_trans_cancel(tp, cancel_flags);
1703	xfs_qm_dqrele(udqp);
1704	xfs_qm_dqrele(gdqp);
1705
1706	if (unlock_dp_on_error)
1707		xfs_iunlock(dp, XFS_ILOCK_EXCL);
1708 std_return:
1709	return error;
1710}
1711
1712int
1713xfs_set_dmattrs(
1714	xfs_inode_t     *ip,
1715	u_int		evmask,
1716	u_int16_t	state)
1717{
1718	xfs_mount_t	*mp = ip->i_mount;
1719	xfs_trans_t	*tp;
1720	int		error;
1721
1722	if (!capable(CAP_SYS_ADMIN))
1723		return XFS_ERROR(EPERM);
1724
1725	if (XFS_FORCED_SHUTDOWN(mp))
1726		return XFS_ERROR(EIO);
1727
1728	tp = xfs_trans_alloc(mp, XFS_TRANS_SET_DMATTRS);
1729	error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES (mp), 0, 0, 0);
1730	if (error) {
1731		xfs_trans_cancel(tp, 0);
1732		return error;
1733	}
1734	xfs_ilock(ip, XFS_ILOCK_EXCL);
1735	xfs_trans_ijoin_ref(tp, ip, XFS_ILOCK_EXCL);
1736
1737	ip->i_d.di_dmevmask = evmask;
1738	ip->i_d.di_dmstate  = state;
1739
1740	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1741	error = xfs_trans_commit(tp, 0);
1742
1743	return error;
1744}
1745
1746/*
1747 * xfs_alloc_file_space()
1748 *      This routine allocates disk space for the given file.
1749 *
1750 *	If alloc_type == 0, this request is for an ALLOCSP type
1751 *	request which will change the file size.  In this case, no
1752 *	DMAPI event will be generated by the call.  A TRUNCATE event
1753 *	will be generated later by xfs_setattr.
1754 *
1755 *	If alloc_type != 0, this request is for a RESVSP type
1756 *	request, and a DMAPI DM_EVENT_WRITE will be generated if the
1757 *	lower block boundary byte address is less than the file's
1758 *	length.
1759 *
1760 * RETURNS:
1761 *       0 on success
1762 *      errno on error
1763 *
1764 */
1765STATIC int
1766xfs_alloc_file_space(
1767	xfs_inode_t		*ip,
1768	xfs_off_t		offset,
1769	xfs_off_t		len,
1770	int			alloc_type,
1771	int			attr_flags)
1772{
1773	xfs_mount_t		*mp = ip->i_mount;
1774	xfs_off_t		count;
1775	xfs_filblks_t		allocated_fsb;
1776	xfs_filblks_t		allocatesize_fsb;
1777	xfs_extlen_t		extsz, temp;
1778	xfs_fileoff_t		startoffset_fsb;
1779	xfs_fsblock_t		firstfsb;
1780	int			nimaps;
1781	int			bmapi_flag;
1782	int			quota_flag;
1783	int			rt;
1784	xfs_trans_t		*tp;
1785	xfs_bmbt_irec_t		imaps[1], *imapp;
1786	xfs_bmap_free_t		free_list;
1787	uint			qblocks, resblks, resrtextents;
1788	int			committed;
1789	int			error;
1790
1791	trace_xfs_alloc_file_space(ip);
1792
1793	if (XFS_FORCED_SHUTDOWN(mp))
1794		return XFS_ERROR(EIO);
1795
1796	error = xfs_qm_dqattach(ip, 0);
1797	if (error)
1798		return error;
1799
1800	if (len <= 0)
1801		return XFS_ERROR(EINVAL);
1802
1803	rt = XFS_IS_REALTIME_INODE(ip);
1804	extsz = xfs_get_extsz_hint(ip);
1805
1806	count = len;
1807	imapp = &imaps[0];
1808	nimaps = 1;
1809	bmapi_flag = XFS_BMAPI_WRITE | alloc_type;
1810	startoffset_fsb	= XFS_B_TO_FSBT(mp, offset);
1811	allocatesize_fsb = XFS_B_TO_FSB(mp, count);
1812
1813	/*
1814	 * Allocate file space until done or until there is an error
1815	 */
1816	while (allocatesize_fsb && !error) {
1817		xfs_fileoff_t	s, e;
1818
1819		/*
1820		 * Determine space reservations for data/realtime.
1821		 */
1822		if (unlikely(extsz)) {
1823			s = startoffset_fsb;
1824			do_div(s, extsz);
1825			s *= extsz;
1826			e = startoffset_fsb + allocatesize_fsb;
1827			if ((temp = do_mod(startoffset_fsb, extsz)))
1828				e += temp;
1829			if ((temp = do_mod(e, extsz)))
1830				e += extsz - temp;
1831		} else {
1832			s = 0;
1833			e = allocatesize_fsb;
1834		}
1835
1836		/*
1837		 * The transaction reservation is limited to a 32-bit block
1838		 * count, hence we need to limit the number of blocks we are
1839		 * trying to reserve to avoid an overflow. We can't allocate
1840		 * more than @nimaps extents, and an extent is limited on disk
1841		 * to MAXEXTLEN (21 bits), so use that to enforce the limit.
1842		 */
1843		resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps));
1844		if (unlikely(rt)) {
1845			resrtextents = qblocks = resblks;
1846			resrtextents /= mp->m_sb.sb_rextsize;
1847			resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1848			quota_flag = XFS_QMOPT_RES_RTBLKS;
1849		} else {
1850			resrtextents = 0;
1851			resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks);
1852			quota_flag = XFS_QMOPT_RES_REGBLKS;
1853		}
1854
1855		/*
1856		 * Allocate and setup the transaction.
1857		 */
1858		tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
1859		error = xfs_trans_reserve(tp, resblks,
1860					  XFS_WRITE_LOG_RES(mp), resrtextents,
1861					  XFS_TRANS_PERM_LOG_RES,
1862					  XFS_WRITE_LOG_COUNT);
1863		/*
1864		 * Check for running out of space
1865		 */
1866		if (error) {
1867			/*
1868			 * Free the transaction structure.
1869			 */
1870			ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1871			xfs_trans_cancel(tp, 0);
1872			break;
1873		}
1874		xfs_ilock(ip, XFS_ILOCK_EXCL);
1875		error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
1876						      0, quota_flag);
1877		if (error)
1878			goto error1;
1879
1880		xfs_trans_ijoin(tp, ip);
1881
1882		/*
1883		 * Issue the xfs_bmapi() call to allocate the blocks
1884		 */
1885		xfs_bmap_init(&free_list, &firstfsb);
1886		error = xfs_bmapi(tp, ip, startoffset_fsb,
1887				  allocatesize_fsb, bmapi_flag,
1888				  &firstfsb, 0, imapp, &nimaps,
1889				  &free_list);
1890		if (error) {
1891			goto error0;
1892		}
1893
1894		/*
1895		 * Complete the transaction
1896		 */
1897		error = xfs_bmap_finish(&tp, &free_list, &committed);
1898		if (error) {
1899			goto error0;
1900		}
1901
1902		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1903		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1904		if (error) {
1905			break;
1906		}
1907
1908		allocated_fsb = imapp->br_blockcount;
1909
1910		if (nimaps == 0) {
1911			error = XFS_ERROR(ENOSPC);
1912			break;
1913		}
1914
1915		startoffset_fsb += allocated_fsb;
1916		allocatesize_fsb -= allocated_fsb;
1917	}
1918
1919	return error;
1920
1921error0:	/* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
1922	xfs_bmap_cancel(&free_list);
1923	xfs_trans_unreserve_quota_nblks(tp, ip, qblocks, 0, quota_flag);
1924
1925error1:	/* Just cancel transaction */
1926	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1927	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1928	return error;
1929}
1930
1931/*
1932 * Zero file bytes between startoff and endoff inclusive.
1933 * The iolock is held exclusive and no blocks are buffered.
1934 *
1935 * This function is used by xfs_free_file_space() to zero
1936 * partial blocks when the range to free is not block aligned.
1937 * When unreserving space with boundaries that are not block
1938 * aligned we round up the start and round down the end
1939 * boundaries and then use this function to zero the parts of
1940 * the blocks that got dropped during the rounding.
1941 */
1942STATIC int
1943xfs_zero_remaining_bytes(
1944	xfs_inode_t		*ip,
1945	xfs_off_t		startoff,
1946	xfs_off_t		endoff)
1947{
1948	xfs_bmbt_irec_t		imap;
1949	xfs_fileoff_t		offset_fsb;
1950	xfs_off_t		lastoffset;
1951	xfs_off_t		offset;
1952	xfs_buf_t		*bp;
1953	xfs_mount_t		*mp = ip->i_mount;
1954	int			nimap;
1955	int			error = 0;
1956
1957	/*
1958	 * Avoid doing I/O beyond eof - it's not necessary
1959	 * since nothing can read beyond eof.  The space will
1960	 * be zeroed when the file is extended anyway.
1961	 */
1962	if (startoff >= ip->i_size)
1963		return 0;
1964
1965	if (endoff > ip->i_size)
1966		endoff = ip->i_size;
1967
1968	bp = xfs_buf_get_uncached(XFS_IS_REALTIME_INODE(ip) ?
1969					mp->m_rtdev_targp : mp->m_ddev_targp,
1970				mp->m_sb.sb_blocksize, XBF_DONT_BLOCK);
1971	if (!bp)
1972		return XFS_ERROR(ENOMEM);
1973
1974	xfs_buf_unlock(bp);
1975
1976	for (offset = startoff; offset <= endoff; offset = lastoffset + 1) {
1977		offset_fsb = XFS_B_TO_FSBT(mp, offset);
1978		nimap = 1;
1979		error = xfs_bmapi(NULL, ip, offset_fsb, 1, 0,
1980			NULL, 0, &imap, &nimap, NULL);
1981		if (error || nimap < 1)
1982			break;
1983		ASSERT(imap.br_blockcount >= 1);
1984		ASSERT(imap.br_startoff == offset_fsb);
1985		lastoffset = XFS_FSB_TO_B(mp, imap.br_startoff + 1) - 1;
1986		if (lastoffset > endoff)
1987			lastoffset = endoff;
1988		if (imap.br_startblock == HOLESTARTBLOCK)
1989			continue;
1990		ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1991		if (imap.br_state == XFS_EXT_UNWRITTEN)
1992			continue;
1993		XFS_BUF_UNDONE(bp);
1994		XFS_BUF_UNWRITE(bp);
1995		XFS_BUF_READ(bp);
1996		XFS_BUF_SET_ADDR(bp, xfs_fsb_to_db(ip, imap.br_startblock));
1997		xfsbdstrat(mp, bp);
1998		error = xfs_buf_iowait(bp);
1999		if (error) {
2000			xfs_ioerror_alert("xfs_zero_remaining_bytes(read)",
2001					  mp, bp, XFS_BUF_ADDR(bp));
2002			break;
2003		}
2004		memset(bp->b_addr +
2005			(offset - XFS_FSB_TO_B(mp, imap.br_startoff)),
2006		      0, lastoffset - offset + 1);
2007		XFS_BUF_UNDONE(bp);
2008		XFS_BUF_UNREAD(bp);
2009		XFS_BUF_WRITE(bp);
2010		xfsbdstrat(mp, bp);
2011		error = xfs_buf_iowait(bp);
2012		if (error) {
2013			xfs_ioerror_alert("xfs_zero_remaining_bytes(write)",
2014					  mp, bp, XFS_BUF_ADDR(bp));
2015			break;
2016		}
2017	}
2018	xfs_buf_free(bp);
2019	return error;
2020}
2021
2022/*
2023 * xfs_free_file_space()
2024 *      This routine frees disk space for the given file.
2025 *
2026 *	This routine is only called by xfs_change_file_space
2027 *	for an UNRESVSP type call.
2028 *
2029 * RETURNS:
2030 *       0 on success
2031 *      errno on error
2032 *
2033 */
2034STATIC int
2035xfs_free_file_space(
2036	xfs_inode_t		*ip,
2037	xfs_off_t		offset,
2038	xfs_off_t		len,
2039	int			attr_flags)
2040{
2041	int			committed;
2042	int			done;
2043	xfs_fileoff_t		endoffset_fsb;
2044	int			error;
2045	xfs_fsblock_t		firstfsb;
2046	xfs_bmap_free_t		free_list;
2047	xfs_bmbt_irec_t		imap;
2048	xfs_off_t		ioffset;
2049	xfs_extlen_t		mod=0;
2050	xfs_mount_t		*mp;
2051	int			nimap;
2052	uint			resblks;
2053	uint			rounding;
2054	int			rt;
2055	xfs_fileoff_t		startoffset_fsb;
2056	xfs_trans_t		*tp;
2057	int			need_iolock = 1;
2058
2059	mp = ip->i_mount;
2060
2061	trace_xfs_free_file_space(ip);
2062
2063	error = xfs_qm_dqattach(ip, 0);
2064	if (error)
2065		return error;
2066
2067	error = 0;
2068	if (len <= 0)	/* if nothing being freed */
2069		return error;
2070	rt = XFS_IS_REALTIME_INODE(ip);
2071	startoffset_fsb	= XFS_B_TO_FSB(mp, offset);
2072	endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
2073
2074	if (attr_flags & XFS_ATTR_NOLOCK)
2075		need_iolock = 0;
2076	if (need_iolock) {
2077		xfs_ilock(ip, XFS_IOLOCK_EXCL);
2078		/* wait for the completion of any pending DIOs */
2079		xfs_ioend_wait(ip);
2080	}
2081
2082	rounding = max_t(uint, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
2083	ioffset = offset & ~(rounding - 1);
2084
2085	if (VN_CACHED(VFS_I(ip)) != 0) {
2086		error = xfs_flushinval_pages(ip, ioffset, -1, FI_REMAPF_LOCKED);
2087		if (error)
2088			goto out_unlock_iolock;
2089	}
2090
2091	/*
2092	 * Need to zero the stuff we're not freeing, on disk.
2093	 * If it's a realtime file & can't use unwritten extents then we
2094	 * actually need to zero the extent edges.  Otherwise xfs_bunmapi
2095	 * will take care of it for us.
2096	 */
2097	if (rt && !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
2098		nimap = 1;
2099		error = xfs_bmapi(NULL, ip, startoffset_fsb,
2100			1, 0, NULL, 0, &imap, &nimap, NULL);
2101		if (error)
2102			goto out_unlock_iolock;
2103		ASSERT(nimap == 0 || nimap == 1);
2104		if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
2105			xfs_daddr_t	block;
2106
2107			ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
2108			block = imap.br_startblock;
2109			mod = do_div(block, mp->m_sb.sb_rextsize);
2110			if (mod)
2111				startoffset_fsb += mp->m_sb.sb_rextsize - mod;
2112		}
2113		nimap = 1;
2114		error = xfs_bmapi(NULL, ip, endoffset_fsb - 1,
2115			1, 0, NULL, 0, &imap, &nimap, NULL);
2116		if (error)
2117			goto out_unlock_iolock;
2118		ASSERT(nimap == 0 || nimap == 1);
2119		if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
2120			ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
2121			mod++;
2122			if (mod && (mod != mp->m_sb.sb_rextsize))
2123				endoffset_fsb -= mod;
2124		}
2125	}
2126	if ((done = (endoffset_fsb <= startoffset_fsb)))
2127		/*
2128		 * One contiguous piece to clear
2129		 */
2130		error = xfs_zero_remaining_bytes(ip, offset, offset + len - 1);
2131	else {
2132		/*
2133		 * Some full blocks, possibly two pieces to clear
2134		 */
2135		if (offset < XFS_FSB_TO_B(mp, startoffset_fsb))
2136			error = xfs_zero_remaining_bytes(ip, offset,
2137				XFS_FSB_TO_B(mp, startoffset_fsb) - 1);
2138		if (!error &&
2139		    XFS_FSB_TO_B(mp, endoffset_fsb) < offset + len)
2140			error = xfs_zero_remaining_bytes(ip,
2141				XFS_FSB_TO_B(mp, endoffset_fsb),
2142				offset + len - 1);
2143	}
2144
2145	/*
2146	 * free file space until done or until there is an error
2147	 */
2148	resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
2149	while (!error && !done) {
2150
2151		/*
2152		 * allocate and setup the transaction. Allow this
2153		 * transaction to dip into the reserve blocks to ensure
2154		 * the freeing of the space succeeds at ENOSPC.
2155		 */
2156		tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
2157		tp->t_flags |= XFS_TRANS_RESERVE;
2158		error = xfs_trans_reserve(tp,
2159					  resblks,
2160					  XFS_WRITE_LOG_RES(mp),
2161					  0,
2162					  XFS_TRANS_PERM_LOG_RES,
2163					  XFS_WRITE_LOG_COUNT);
2164
2165		/*
2166		 * check for running out of space
2167		 */
2168		if (error) {
2169			/*
2170			 * Free the transaction structure.
2171			 */
2172			ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
2173			xfs_trans_cancel(tp, 0);
2174			break;
2175		}
2176		xfs_ilock(ip, XFS_ILOCK_EXCL);
2177		error = xfs_trans_reserve_quota(tp, mp,
2178				ip->i_udquot, ip->i_gdquot,
2179				resblks, 0, XFS_QMOPT_RES_REGBLKS);
2180		if (error)
2181			goto error1;
2182
2183		xfs_trans_ijoin(tp, ip);
2184
2185		/*
2186		 * issue the bunmapi() call to free the blocks
2187		 */
2188		xfs_bmap_init(&free_list, &firstfsb);
2189		error = xfs_bunmapi(tp, ip, startoffset_fsb,
2190				  endoffset_fsb - startoffset_fsb,
2191				  0, 2, &firstfsb, &free_list, &done);
2192		if (error) {
2193			goto error0;
2194		}
2195
2196		/*
2197		 * complete the transaction
2198		 */
2199		error = xfs_bmap_finish(&tp, &free_list, &committed);
2200		if (error) {
2201			goto error0;
2202		}
2203
2204		error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2205		xfs_iunlock(ip, XFS_ILOCK_EXCL);
2206	}
2207
2208 out_unlock_iolock:
2209	if (need_iolock)
2210		xfs_iunlock(ip, XFS_IOLOCK_EXCL);
2211	return error;
2212
2213 error0:
2214	xfs_bmap_cancel(&free_list);
2215 error1:
2216	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
2217	xfs_iunlock(ip, need_iolock ? (XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL) :
2218		    XFS_ILOCK_EXCL);
2219	return error;
2220}
2221
2222/*
2223 * xfs_change_file_space()
2224 *      This routine allocates or frees disk space for the given file.
2225 *      The user specified parameters are checked for alignment and size
2226 *      limitations.
2227 *
2228 * RETURNS:
2229 *       0 on success
2230 *      errno on error
2231 *
2232 */
2233int
2234xfs_change_file_space(
2235	xfs_inode_t	*ip,
2236	int		cmd,
2237	xfs_flock64_t	*bf,
2238	xfs_off_t	offset,
2239	int		attr_flags)
2240{
2241	xfs_mount_t	*mp = ip->i_mount;
2242	int		clrprealloc;
2243	int		error;
2244	xfs_fsize_t	fsize;
2245	int		setprealloc;
2246	xfs_off_t	startoffset;
2247	xfs_off_t	llen;
2248	xfs_trans_t	*tp;
2249	struct iattr	iattr;
2250	int		prealloc_type;
2251
2252	if (!S_ISREG(ip->i_d.di_mode))
2253		return XFS_ERROR(EINVAL);
2254
2255	switch (bf->l_whence) {
2256	case 0: /*SEEK_SET*/
2257		break;
2258	case 1: /*SEEK_CUR*/
2259		bf->l_start += offset;
2260		break;
2261	case 2: /*SEEK_END*/
2262		bf->l_start += ip->i_size;
2263		break;
2264	default:
2265		return XFS_ERROR(EINVAL);
2266	}
2267
2268	llen = bf->l_len > 0 ? bf->l_len - 1 : bf->l_len;
2269
2270	if (   (bf->l_start < 0)
2271	    || (bf->l_start > XFS_MAXIOFFSET(mp))
2272	    || (bf->l_start + llen < 0)
2273	    || (bf->l_start + llen > XFS_MAXIOFFSET(mp)))
2274		return XFS_ERROR(EINVAL);
2275
2276	bf->l_whence = 0;
2277
2278	startoffset = bf->l_start;
2279	fsize = ip->i_size;
2280
2281	/*
2282	 * XFS_IOC_RESVSP and XFS_IOC_UNRESVSP will reserve or unreserve
2283	 * file space.
2284	 * These calls do NOT zero the data space allocated to the file,
2285	 * nor do they change the file size.
2286	 *
2287	 * XFS_IOC_ALLOCSP and XFS_IOC_FREESP will allocate and free file
2288	 * space.
2289	 * These calls cause the new file data to be zeroed and the file
2290	 * size to be changed.
2291	 */
2292	setprealloc = clrprealloc = 0;
2293	prealloc_type = XFS_BMAPI_PREALLOC;
2294
2295	switch (cmd) {
2296	case XFS_IOC_ZERO_RANGE:
2297		prealloc_type |= XFS_BMAPI_CONVERT;
2298		xfs_tosspages(ip, startoffset, startoffset + bf->l_len, 0);
2299		/* FALLTHRU */
2300	case XFS_IOC_RESVSP:
2301	case XFS_IOC_RESVSP64:
2302		error = xfs_alloc_file_space(ip, startoffset, bf->l_len,
2303						prealloc_type, attr_flags);
2304		if (error)
2305			return error;
2306		setprealloc = 1;
2307		break;
2308
2309	case XFS_IOC_UNRESVSP:
2310	case XFS_IOC_UNRESVSP64:
2311		if ((error = xfs_free_file_space(ip, startoffset, bf->l_len,
2312								attr_flags)))
2313			return error;
2314		break;
2315
2316	case XFS_IOC_ALLOCSP:
2317	case XFS_IOC_ALLOCSP64:
2318	case XFS_IOC_FREESP:
2319	case XFS_IOC_FREESP64:
 
 
 
 
 
 
 
 
 
 
 
2320		if (startoffset > fsize) {
2321			error = xfs_alloc_file_space(ip, fsize,
2322					startoffset - fsize, 0, attr_flags);
2323			if (error)
 
 
2324				break;
 
2325		}
2326
2327		iattr.ia_valid = ATTR_SIZE;
2328		iattr.ia_size = startoffset;
2329
2330		error = xfs_setattr_size(ip, &iattr, attr_flags);
 
 
2331
2332		if (error)
2333			return error;
2334
2335		clrprealloc = 1;
2336		break;
2337
2338	default:
2339		ASSERT(0);
2340		return XFS_ERROR(EINVAL);
2341	}
2342
2343	/*
2344	 * update the inode timestamp, mode, and prealloc flag bits
2345	 */
2346	tp = xfs_trans_alloc(mp, XFS_TRANS_WRITEID);
2347
2348	if ((error = xfs_trans_reserve(tp, 0, XFS_WRITEID_LOG_RES(mp),
2349				      0, 0, 0))) {
2350		/* ASSERT(0); */
2351		xfs_trans_cancel(tp, 0);
2352		return error;
2353	}
2354
2355	xfs_ilock(ip, XFS_ILOCK_EXCL);
2356
2357	xfs_trans_ijoin(tp, ip);
2358
2359	if ((attr_flags & XFS_ATTR_DMI) == 0) {
2360		ip->i_d.di_mode &= ~S_ISUID;
2361
2362		/*
2363		 * Note that we don't have to worry about mandatory
2364		 * file locking being disabled here because we only
2365		 * clear the S_ISGID bit if the Group execute bit is
2366		 * on, but if it was on then mandatory locking wouldn't
2367		 * have been enabled.
2368		 */
2369		if (ip->i_d.di_mode & S_IXGRP)
2370			ip->i_d.di_mode &= ~S_ISGID;
2371
2372		xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2373	}
2374	if (setprealloc)
2375		ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
2376	else if (clrprealloc)
2377		ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
2378
2379	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2380	if (attr_flags & XFS_ATTR_SYNC)
2381		xfs_trans_set_sync(tp);
2382
2383	error = xfs_trans_commit(tp, 0);
2384
2385	xfs_iunlock(ip, XFS_ILOCK_EXCL);
2386
2387	return error;
2388}