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v3.15
   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#include <linux/log2.h>
  19
  20#include "xfs.h"
  21#include "xfs_fs.h"
  22#include "xfs_shared.h"
  23#include "xfs_format.h"
  24#include "xfs_log_format.h"
  25#include "xfs_trans_resv.h"
  26#include "xfs_inum.h"
  27#include "xfs_sb.h"
  28#include "xfs_ag.h"
  29#include "xfs_mount.h"
 
  30#include "xfs_inode.h"
  31#include "xfs_da_format.h"
  32#include "xfs_da_btree.h"
  33#include "xfs_dir2.h"
  34#include "xfs_attr_sf.h"
  35#include "xfs_attr.h"
  36#include "xfs_trans_space.h"
  37#include "xfs_trans.h"
  38#include "xfs_buf_item.h"
  39#include "xfs_inode_item.h"
  40#include "xfs_ialloc.h"
  41#include "xfs_bmap.h"
  42#include "xfs_bmap_util.h"
  43#include "xfs_error.h"
  44#include "xfs_quota.h"
  45#include "xfs_filestream.h"
  46#include "xfs_cksum.h"
  47#include "xfs_trace.h"
  48#include "xfs_icache.h"
  49#include "xfs_symlink.h"
  50#include "xfs_trans_priv.h"
  51#include "xfs_log.h"
  52#include "xfs_bmap_btree.h"
 
  53
  54kmem_zone_t *xfs_inode_zone;
  55
  56/*
  57 * Used in xfs_itruncate_extents().  This is the maximum number of extents
  58 * freed from a file in a single transaction.
  59 */
  60#define	XFS_ITRUNC_MAX_EXTENTS	2
  61
  62STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *);
  63
  64STATIC int xfs_iunlink_remove(xfs_trans_t *, xfs_inode_t *);
  65
  66/*
  67 * helper function to extract extent size hint from inode
  68 */
  69xfs_extlen_t
  70xfs_get_extsz_hint(
  71	struct xfs_inode	*ip)
  72{
  73	if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
  74		return ip->i_d.di_extsize;
  75	if (XFS_IS_REALTIME_INODE(ip))
  76		return ip->i_mount->m_sb.sb_rextsize;
  77	return 0;
  78}
  79
  80/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  81 * These two are wrapper routines around the xfs_ilock() routine used to
  82 * centralize some grungy code.  They are used in places that wish to lock the
  83 * inode solely for reading the extents.  The reason these places can't just
  84 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
  85 * bringing in of the extents from disk for a file in b-tree format.  If the
  86 * inode is in b-tree format, then we need to lock the inode exclusively until
  87 * the extents are read in.  Locking it exclusively all the time would limit
  88 * our parallelism unnecessarily, though.  What we do instead is check to see
  89 * if the extents have been read in yet, and only lock the inode exclusively
  90 * if they have not.
  91 *
  92 * The functions return a value which should be given to the corresponding
  93 * xfs_iunlock() call.
  94 */
  95uint
  96xfs_ilock_data_map_shared(
  97	struct xfs_inode	*ip)
  98{
  99	uint			lock_mode = XFS_ILOCK_SHARED;
 100
 101	if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
 102	    (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
 103		lock_mode = XFS_ILOCK_EXCL;
 104	xfs_ilock(ip, lock_mode);
 105	return lock_mode;
 106}
 107
 108uint
 109xfs_ilock_attr_map_shared(
 110	struct xfs_inode	*ip)
 111{
 112	uint			lock_mode = XFS_ILOCK_SHARED;
 113
 114	if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
 115	    (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
 116		lock_mode = XFS_ILOCK_EXCL;
 117	xfs_ilock(ip, lock_mode);
 118	return lock_mode;
 119}
 120
 121/*
 122 * The xfs inode contains 2 locks: a multi-reader lock called the
 123 * i_iolock and a multi-reader lock called the i_lock.  This routine
 124 * allows either or both of the locks to be obtained.
 125 *
 126 * The 2 locks should always be ordered so that the IO lock is
 127 * obtained first in order to prevent deadlock.
 128 *
 129 * ip -- the inode being locked
 130 * lock_flags -- this parameter indicates the inode's locks
 131 *       to be locked.  It can be:
 132 *		XFS_IOLOCK_SHARED,
 133 *		XFS_IOLOCK_EXCL,
 134 *		XFS_ILOCK_SHARED,
 135 *		XFS_ILOCK_EXCL,
 136 *		XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED,
 137 *		XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL,
 138 *		XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED,
 139 *		XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL
 
 
 
 
 
 
 
 
 
 
 140 */
 141void
 142xfs_ilock(
 143	xfs_inode_t		*ip,
 144	uint			lock_flags)
 145{
 146	trace_xfs_ilock(ip, lock_flags, _RET_IP_);
 147
 148	/*
 149	 * You can't set both SHARED and EXCL for the same lock,
 150	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 151	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 152	 */
 153	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 154	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 
 
 155	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 156	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 157	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
 158
 159	if (lock_flags & XFS_IOLOCK_EXCL)
 160		mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
 161	else if (lock_flags & XFS_IOLOCK_SHARED)
 162		mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
 
 
 
 
 
 
 
 
 163
 164	if (lock_flags & XFS_ILOCK_EXCL)
 165		mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 166	else if (lock_flags & XFS_ILOCK_SHARED)
 167		mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 168}
 169
 170/*
 171 * This is just like xfs_ilock(), except that the caller
 172 * is guaranteed not to sleep.  It returns 1 if it gets
 173 * the requested locks and 0 otherwise.  If the IO lock is
 174 * obtained but the inode lock cannot be, then the IO lock
 175 * is dropped before returning.
 176 *
 177 * ip -- the inode being locked
 178 * lock_flags -- this parameter indicates the inode's locks to be
 179 *       to be locked.  See the comment for xfs_ilock() for a list
 180 *	 of valid values.
 181 */
 182int
 183xfs_ilock_nowait(
 184	xfs_inode_t		*ip,
 185	uint			lock_flags)
 186{
 187	trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
 188
 189	/*
 190	 * You can't set both SHARED and EXCL for the same lock,
 191	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 192	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 193	 */
 194	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 195	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 
 
 196	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 197	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 198	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
 199
 200	if (lock_flags & XFS_IOLOCK_EXCL) {
 201		if (!mrtryupdate(&ip->i_iolock))
 202			goto out;
 203	} else if (lock_flags & XFS_IOLOCK_SHARED) {
 204		if (!mrtryaccess(&ip->i_iolock))
 205			goto out;
 206	}
 
 
 
 
 
 
 
 
 
 207	if (lock_flags & XFS_ILOCK_EXCL) {
 208		if (!mrtryupdate(&ip->i_lock))
 209			goto out_undo_iolock;
 210	} else if (lock_flags & XFS_ILOCK_SHARED) {
 211		if (!mrtryaccess(&ip->i_lock))
 212			goto out_undo_iolock;
 213	}
 214	return 1;
 215
 216 out_undo_iolock:
 
 
 
 
 
 217	if (lock_flags & XFS_IOLOCK_EXCL)
 218		mrunlock_excl(&ip->i_iolock);
 219	else if (lock_flags & XFS_IOLOCK_SHARED)
 220		mrunlock_shared(&ip->i_iolock);
 221 out:
 222	return 0;
 223}
 224
 225/*
 226 * xfs_iunlock() is used to drop the inode locks acquired with
 227 * xfs_ilock() and xfs_ilock_nowait().  The caller must pass
 228 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
 229 * that we know which locks to drop.
 230 *
 231 * ip -- the inode being unlocked
 232 * lock_flags -- this parameter indicates the inode's locks to be
 233 *       to be unlocked.  See the comment for xfs_ilock() for a list
 234 *	 of valid values for this parameter.
 235 *
 236 */
 237void
 238xfs_iunlock(
 239	xfs_inode_t		*ip,
 240	uint			lock_flags)
 241{
 242	/*
 243	 * You can't set both SHARED and EXCL for the same lock,
 244	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 245	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 246	 */
 247	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 248	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 
 
 249	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 250	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 251	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
 252	ASSERT(lock_flags != 0);
 253
 254	if (lock_flags & XFS_IOLOCK_EXCL)
 255		mrunlock_excl(&ip->i_iolock);
 256	else if (lock_flags & XFS_IOLOCK_SHARED)
 257		mrunlock_shared(&ip->i_iolock);
 
 
 
 
 
 258
 259	if (lock_flags & XFS_ILOCK_EXCL)
 260		mrunlock_excl(&ip->i_lock);
 261	else if (lock_flags & XFS_ILOCK_SHARED)
 262		mrunlock_shared(&ip->i_lock);
 263
 264	trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
 265}
 266
 267/*
 268 * give up write locks.  the i/o lock cannot be held nested
 269 * if it is being demoted.
 270 */
 271void
 272xfs_ilock_demote(
 273	xfs_inode_t		*ip,
 274	uint			lock_flags)
 275{
 276	ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL));
 277	ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
 
 278
 279	if (lock_flags & XFS_ILOCK_EXCL)
 280		mrdemote(&ip->i_lock);
 
 
 281	if (lock_flags & XFS_IOLOCK_EXCL)
 282		mrdemote(&ip->i_iolock);
 283
 284	trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
 285}
 286
 287#if defined(DEBUG) || defined(XFS_WARN)
 288int
 289xfs_isilocked(
 290	xfs_inode_t		*ip,
 291	uint			lock_flags)
 292{
 293	if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
 294		if (!(lock_flags & XFS_ILOCK_SHARED))
 295			return !!ip->i_lock.mr_writer;
 296		return rwsem_is_locked(&ip->i_lock.mr_lock);
 297	}
 298
 
 
 
 
 
 
 299	if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
 300		if (!(lock_flags & XFS_IOLOCK_SHARED))
 301			return !!ip->i_iolock.mr_writer;
 302		return rwsem_is_locked(&ip->i_iolock.mr_lock);
 
 303	}
 304
 305	ASSERT(0);
 306	return 0;
 307}
 308#endif
 309
 310#ifdef DEBUG
 311int xfs_locked_n;
 312int xfs_small_retries;
 313int xfs_middle_retries;
 314int xfs_lots_retries;
 315int xfs_lock_delays;
 316#endif
 317
 318/*
 319 * Bump the subclass so xfs_lock_inodes() acquires each lock with
 320 * a different value
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 321 */
 322static inline int
 323xfs_lock_inumorder(int lock_mode, int subclass)
 324{
 325	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
 326		lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT;
 327	if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))
 328		lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT;
 329
 330	return lock_mode;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 331}
 332
 333/*
 334 * The following routine will lock n inodes in exclusive mode.
 335 * We assume the caller calls us with the inodes in i_ino order.
 336 *
 337 * We need to detect deadlock where an inode that we lock
 338 * is in the AIL and we start waiting for another inode that is locked
 339 * by a thread in a long running transaction (such as truncate). This can
 340 * result in deadlock since the long running trans might need to wait
 341 * for the inode we just locked in order to push the tail and free space
 342 * in the log.
 
 
 
 
 343 */
 344void
 345xfs_lock_inodes(
 346	xfs_inode_t	**ips,
 347	int		inodes,
 348	uint		lock_mode)
 349{
 350	int		attempts = 0, i, j, try_lock;
 351	xfs_log_item_t	*lp;
 352
 353	ASSERT(ips && (inodes >= 2)); /* we need at least two */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 354
 355	try_lock = 0;
 356	i = 0;
 357
 358again:
 359	for (; i < inodes; i++) {
 360		ASSERT(ips[i]);
 361
 362		if (i && (ips[i] == ips[i-1]))	/* Already locked */
 363			continue;
 364
 365		/*
 366		 * If try_lock is not set yet, make sure all locked inodes
 367		 * are not in the AIL.
 368		 * If any are, set try_lock to be used later.
 369		 */
 370
 371		if (!try_lock) {
 372			for (j = (i - 1); j >= 0 && !try_lock; j--) {
 373				lp = (xfs_log_item_t *)ips[j]->i_itemp;
 374				if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
 375					try_lock++;
 376				}
 377			}
 378		}
 379
 380		/*
 381		 * If any of the previous locks we have locked is in the AIL,
 382		 * we must TRY to get the second and subsequent locks. If
 383		 * we can't get any, we must release all we have
 384		 * and try again.
 385		 */
 
 
 
 
 
 
 
 
 
 386
 387		if (try_lock) {
 388			/* try_lock must be 0 if i is 0. */
 
 
 
 
 389			/*
 390			 * try_lock means we have an inode locked
 391			 * that is in the AIL.
 
 392			 */
 393			ASSERT(i != 0);
 394			if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) {
 395				attempts++;
 396
 397				/*
 398				 * Unlock all previous guys and try again.
 399				 * xfs_iunlock will try to push the tail
 400				 * if the inode is in the AIL.
 401				 */
 402
 403				for(j = i - 1; j >= 0; j--) {
 404
 405					/*
 406					 * Check to see if we've already
 407					 * unlocked this one.
 408					 * Not the first one going back,
 409					 * and the inode ptr is the same.
 410					 */
 411					if ((j != (i - 1)) && ips[j] ==
 412								ips[j+1])
 413						continue;
 414
 415					xfs_iunlock(ips[j], lock_mode);
 416				}
 417
 418				if ((attempts % 5) == 0) {
 419					delay(1); /* Don't just spin the CPU */
 420#ifdef DEBUG
 421					xfs_lock_delays++;
 422#endif
 423				}
 424				i = 0;
 425				try_lock = 0;
 426				goto again;
 427			}
 428		} else {
 429			xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
 430		}
 
 
 
 431	}
 432
 433#ifdef DEBUG
 434	if (attempts) {
 435		if (attempts < 5) xfs_small_retries++;
 436		else if (attempts < 100) xfs_middle_retries++;
 437		else xfs_lots_retries++;
 438	} else {
 439		xfs_locked_n++;
 440	}
 441#endif
 442}
 443
 444/*
 445 * xfs_lock_two_inodes() can only be used to lock one type of lock
 446 * at a time - the iolock or the ilock, but not both at once. If
 447 * we lock both at once, lockdep will report false positives saying
 448 * we have violated locking orders.
 449 */
 450void
 451xfs_lock_two_inodes(
 452	xfs_inode_t		*ip0,
 453	xfs_inode_t		*ip1,
 454	uint			lock_mode)
 455{
 456	xfs_inode_t		*temp;
 457	int			attempts = 0;
 458	xfs_log_item_t		*lp;
 459
 460	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
 461		ASSERT((lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) == 0);
 
 
 462	ASSERT(ip0->i_ino != ip1->i_ino);
 463
 464	if (ip0->i_ino > ip1->i_ino) {
 465		temp = ip0;
 466		ip0 = ip1;
 467		ip1 = temp;
 468	}
 469
 470 again:
 471	xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0));
 472
 473	/*
 474	 * If the first lock we have locked is in the AIL, we must TRY to get
 475	 * the second lock. If we can't get it, we must release the first one
 476	 * and try again.
 477	 */
 478	lp = (xfs_log_item_t *)ip0->i_itemp;
 479	if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
 480		if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) {
 481			xfs_iunlock(ip0, lock_mode);
 482			if ((++attempts % 5) == 0)
 483				delay(1); /* Don't just spin the CPU */
 484			goto again;
 485		}
 486	} else {
 487		xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1));
 488	}
 489}
 490
 491
 492void
 493__xfs_iflock(
 494	struct xfs_inode	*ip)
 495{
 496	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
 497	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
 498
 499	do {
 500		prepare_to_wait_exclusive(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
 501		if (xfs_isiflocked(ip))
 502			io_schedule();
 503	} while (!xfs_iflock_nowait(ip));
 504
 505	finish_wait(wq, &wait.wait);
 506}
 507
 508STATIC uint
 509_xfs_dic2xflags(
 510	__uint16_t		di_flags)
 
 
 511{
 512	uint			flags = 0;
 513
 514	if (di_flags & XFS_DIFLAG_ANY) {
 515		if (di_flags & XFS_DIFLAG_REALTIME)
 516			flags |= XFS_XFLAG_REALTIME;
 517		if (di_flags & XFS_DIFLAG_PREALLOC)
 518			flags |= XFS_XFLAG_PREALLOC;
 519		if (di_flags & XFS_DIFLAG_IMMUTABLE)
 520			flags |= XFS_XFLAG_IMMUTABLE;
 521		if (di_flags & XFS_DIFLAG_APPEND)
 522			flags |= XFS_XFLAG_APPEND;
 523		if (di_flags & XFS_DIFLAG_SYNC)
 524			flags |= XFS_XFLAG_SYNC;
 525		if (di_flags & XFS_DIFLAG_NOATIME)
 526			flags |= XFS_XFLAG_NOATIME;
 527		if (di_flags & XFS_DIFLAG_NODUMP)
 528			flags |= XFS_XFLAG_NODUMP;
 529		if (di_flags & XFS_DIFLAG_RTINHERIT)
 530			flags |= XFS_XFLAG_RTINHERIT;
 531		if (di_flags & XFS_DIFLAG_PROJINHERIT)
 532			flags |= XFS_XFLAG_PROJINHERIT;
 533		if (di_flags & XFS_DIFLAG_NOSYMLINKS)
 534			flags |= XFS_XFLAG_NOSYMLINKS;
 535		if (di_flags & XFS_DIFLAG_EXTSIZE)
 536			flags |= XFS_XFLAG_EXTSIZE;
 537		if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
 538			flags |= XFS_XFLAG_EXTSZINHERIT;
 539		if (di_flags & XFS_DIFLAG_NODEFRAG)
 540			flags |= XFS_XFLAG_NODEFRAG;
 541		if (di_flags & XFS_DIFLAG_FILESTREAM)
 542			flags |= XFS_XFLAG_FILESTREAM;
 543	}
 544
 
 
 
 
 
 
 
 
 
 
 545	return flags;
 546}
 547
 548uint
 549xfs_ip2xflags(
 550	xfs_inode_t		*ip)
 551{
 552	xfs_icdinode_t		*dic = &ip->i_d;
 553
 554	return _xfs_dic2xflags(dic->di_flags) |
 555				(XFS_IFORK_Q(ip) ? XFS_XFLAG_HASATTR : 0);
 556}
 557
 558uint
 559xfs_dic2xflags(
 560	xfs_dinode_t		*dip)
 561{
 562	return _xfs_dic2xflags(be16_to_cpu(dip->di_flags)) |
 563				(XFS_DFORK_Q(dip) ? XFS_XFLAG_HASATTR : 0);
 564}
 565
 566/*
 567 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
 568 * is allowed, otherwise it has to be an exact match. If a CI match is found,
 569 * ci_name->name will point to a the actual name (caller must free) or
 570 * will be set to NULL if an exact match is found.
 571 */
 572int
 573xfs_lookup(
 574	xfs_inode_t		*dp,
 575	struct xfs_name		*name,
 576	xfs_inode_t		**ipp,
 577	struct xfs_name		*ci_name)
 578{
 579	xfs_ino_t		inum;
 580	int			error;
 581	uint			lock_mode;
 582
 583	trace_xfs_lookup(dp, name);
 584
 585	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
 586		return XFS_ERROR(EIO);
 587
 588	lock_mode = xfs_ilock_data_map_shared(dp);
 589	error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
 590	xfs_iunlock(dp, lock_mode);
 591
 592	if (error)
 593		goto out;
 594
 595	error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
 596	if (error)
 597		goto out_free_name;
 598
 599	return 0;
 600
 601out_free_name:
 602	if (ci_name)
 603		kmem_free(ci_name->name);
 604out:
 605	*ipp = NULL;
 606	return error;
 607}
 608
 609/*
 610 * Allocate an inode on disk and return a copy of its in-core version.
 611 * The in-core inode is locked exclusively.  Set mode, nlink, and rdev
 612 * appropriately within the inode.  The uid and gid for the inode are
 613 * set according to the contents of the given cred structure.
 614 *
 615 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
 616 * has a free inode available, call xfs_iget() to obtain the in-core
 617 * version of the allocated inode.  Finally, fill in the inode and
 618 * log its initial contents.  In this case, ialloc_context would be
 619 * set to NULL.
 620 *
 621 * If xfs_dialloc() does not have an available inode, it will replenish
 622 * its supply by doing an allocation. Since we can only do one
 623 * allocation within a transaction without deadlocks, we must commit
 624 * the current transaction before returning the inode itself.
 625 * In this case, therefore, we will set ialloc_context and return.
 626 * The caller should then commit the current transaction, start a new
 627 * transaction, and call xfs_ialloc() again to actually get the inode.
 628 *
 629 * To ensure that some other process does not grab the inode that
 630 * was allocated during the first call to xfs_ialloc(), this routine
 631 * also returns the [locked] bp pointing to the head of the freelist
 632 * as ialloc_context.  The caller should hold this buffer across
 633 * the commit and pass it back into this routine on the second call.
 634 *
 635 * If we are allocating quota inodes, we do not have a parent inode
 636 * to attach to or associate with (i.e. pip == NULL) because they
 637 * are not linked into the directory structure - they are attached
 638 * directly to the superblock - and so have no parent.
 639 */
 640int
 641xfs_ialloc(
 642	xfs_trans_t	*tp,
 643	xfs_inode_t	*pip,
 644	umode_t		mode,
 645	xfs_nlink_t	nlink,
 646	xfs_dev_t	rdev,
 647	prid_t		prid,
 648	int		okalloc,
 649	xfs_buf_t	**ialloc_context,
 650	xfs_inode_t	**ipp)
 651{
 652	struct xfs_mount *mp = tp->t_mountp;
 653	xfs_ino_t	ino;
 654	xfs_inode_t	*ip;
 655	uint		flags;
 656	int		error;
 657	timespec_t	tv;
 658	int		filestreams = 0;
 659
 660	/*
 661	 * Call the space management code to pick
 662	 * the on-disk inode to be allocated.
 663	 */
 664	error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
 665			    ialloc_context, &ino);
 666	if (error)
 667		return error;
 668	if (*ialloc_context || ino == NULLFSINO) {
 669		*ipp = NULL;
 670		return 0;
 671	}
 672	ASSERT(*ialloc_context == NULL);
 673
 674	/*
 675	 * Get the in-core inode with the lock held exclusively.
 676	 * This is because we're setting fields here we need
 677	 * to prevent others from looking at until we're done.
 678	 */
 679	error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
 680			 XFS_ILOCK_EXCL, &ip);
 681	if (error)
 682		return error;
 683	ASSERT(ip != NULL);
 684
 685	ip->i_d.di_mode = mode;
 686	ip->i_d.di_onlink = 0;
 687	ip->i_d.di_nlink = nlink;
 688	ASSERT(ip->i_d.di_nlink == nlink);
 689	ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
 690	ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
 691	xfs_set_projid(ip, prid);
 692	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
 693
 694	/*
 695	 * If the superblock version is up to where we support new format
 696	 * inodes and this is currently an old format inode, then change
 697	 * the inode version number now.  This way we only do the conversion
 698	 * here rather than here and in the flush/logging code.
 699	 */
 700	if (xfs_sb_version_hasnlink(&mp->m_sb) &&
 701	    ip->i_d.di_version == 1) {
 702		ip->i_d.di_version = 2;
 703		/*
 704		 * We've already zeroed the old link count, the projid field,
 705		 * and the pad field.
 706		 */
 707	}
 708
 709	/*
 710	 * Project ids won't be stored on disk if we are using a version 1 inode.
 711	 */
 712	if ((prid != 0) && (ip->i_d.di_version == 1))
 713		xfs_bump_ino_vers2(tp, ip);
 714
 715	if (pip && XFS_INHERIT_GID(pip)) {
 716		ip->i_d.di_gid = pip->i_d.di_gid;
 717		if ((pip->i_d.di_mode & S_ISGID) && S_ISDIR(mode)) {
 718			ip->i_d.di_mode |= S_ISGID;
 719		}
 720	}
 721
 722	/*
 723	 * If the group ID of the new file does not match the effective group
 724	 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
 725	 * (and only if the irix_sgid_inherit compatibility variable is set).
 726	 */
 727	if ((irix_sgid_inherit) &&
 728	    (ip->i_d.di_mode & S_ISGID) &&
 729	    (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid)))) {
 730		ip->i_d.di_mode &= ~S_ISGID;
 731	}
 732
 733	ip->i_d.di_size = 0;
 734	ip->i_d.di_nextents = 0;
 735	ASSERT(ip->i_d.di_nblocks == 0);
 736
 737	nanotime(&tv);
 738	ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec;
 739	ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec;
 740	ip->i_d.di_atime = ip->i_d.di_mtime;
 741	ip->i_d.di_ctime = ip->i_d.di_mtime;
 742
 743	/*
 744	 * di_gen will have been taken care of in xfs_iread.
 745	 */
 746	ip->i_d.di_extsize = 0;
 747	ip->i_d.di_dmevmask = 0;
 748	ip->i_d.di_dmstate = 0;
 749	ip->i_d.di_flags = 0;
 750
 751	if (ip->i_d.di_version == 3) {
 752		ASSERT(ip->i_d.di_ino == ino);
 753		ASSERT(uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid));
 754		ip->i_d.di_crc = 0;
 755		ip->i_d.di_changecount = 1;
 756		ip->i_d.di_lsn = 0;
 757		ip->i_d.di_flags2 = 0;
 758		memset(&(ip->i_d.di_pad2[0]), 0, sizeof(ip->i_d.di_pad2));
 759		ip->i_d.di_crtime = ip->i_d.di_mtime;
 
 760	}
 761
 762
 763	flags = XFS_ILOG_CORE;
 764	switch (mode & S_IFMT) {
 765	case S_IFIFO:
 766	case S_IFCHR:
 767	case S_IFBLK:
 768	case S_IFSOCK:
 769		ip->i_d.di_format = XFS_DINODE_FMT_DEV;
 770		ip->i_df.if_u2.if_rdev = rdev;
 771		ip->i_df.if_flags = 0;
 772		flags |= XFS_ILOG_DEV;
 773		break;
 774	case S_IFREG:
 775		/*
 776		 * we can't set up filestreams until after the VFS inode
 777		 * is set up properly.
 778		 */
 779		if (pip && xfs_inode_is_filestream(pip))
 780			filestreams = 1;
 781		/* fall through */
 782	case S_IFDIR:
 783		if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
 784			uint	di_flags = 0;
 
 785
 786			if (S_ISDIR(mode)) {
 787				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
 788					di_flags |= XFS_DIFLAG_RTINHERIT;
 789				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
 790					di_flags |= XFS_DIFLAG_EXTSZINHERIT;
 791					ip->i_d.di_extsize = pip->i_d.di_extsize;
 792				}
 
 
 793			} else if (S_ISREG(mode)) {
 794				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
 795					di_flags |= XFS_DIFLAG_REALTIME;
 796				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
 797					di_flags |= XFS_DIFLAG_EXTSIZE;
 798					ip->i_d.di_extsize = pip->i_d.di_extsize;
 799				}
 800			}
 801			if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
 802			    xfs_inherit_noatime)
 803				di_flags |= XFS_DIFLAG_NOATIME;
 804			if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
 805			    xfs_inherit_nodump)
 806				di_flags |= XFS_DIFLAG_NODUMP;
 807			if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
 808			    xfs_inherit_sync)
 809				di_flags |= XFS_DIFLAG_SYNC;
 810			if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
 811			    xfs_inherit_nosymlinks)
 812				di_flags |= XFS_DIFLAG_NOSYMLINKS;
 813			if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
 814				di_flags |= XFS_DIFLAG_PROJINHERIT;
 815			if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
 816			    xfs_inherit_nodefrag)
 817				di_flags |= XFS_DIFLAG_NODEFRAG;
 818			if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
 819				di_flags |= XFS_DIFLAG_FILESTREAM;
 
 
 
 820			ip->i_d.di_flags |= di_flags;
 
 
 
 
 
 
 
 
 
 
 821		}
 822		/* FALLTHROUGH */
 823	case S_IFLNK:
 824		ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
 825		ip->i_df.if_flags = XFS_IFEXTENTS;
 826		ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
 827		ip->i_df.if_u1.if_extents = NULL;
 828		break;
 829	default:
 830		ASSERT(0);
 831	}
 832	/*
 833	 * Attribute fork settings for new inode.
 834	 */
 835	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
 836	ip->i_d.di_anextents = 0;
 837
 838	/*
 839	 * Log the new values stuffed into the inode.
 840	 */
 841	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 842	xfs_trans_log_inode(tp, ip, flags);
 843
 844	/* now that we have an i_mode we can setup inode ops and unlock */
 845	xfs_setup_inode(ip);
 846
 847	/* now we have set up the vfs inode we can associate the filestream */
 848	if (filestreams) {
 849		error = xfs_filestream_associate(pip, ip);
 850		if (error < 0)
 851			return -error;
 852		if (!error)
 853			xfs_iflags_set(ip, XFS_IFILESTREAM);
 854	}
 855
 856	*ipp = ip;
 857	return 0;
 858}
 859
 860/*
 861 * Allocates a new inode from disk and return a pointer to the
 862 * incore copy. This routine will internally commit the current
 863 * transaction and allocate a new one if the Space Manager needed
 864 * to do an allocation to replenish the inode free-list.
 865 *
 866 * This routine is designed to be called from xfs_create and
 867 * xfs_create_dir.
 868 *
 869 */
 870int
 871xfs_dir_ialloc(
 872	xfs_trans_t	**tpp,		/* input: current transaction;
 873					   output: may be a new transaction. */
 874	xfs_inode_t	*dp,		/* directory within whose allocate
 875					   the inode. */
 876	umode_t		mode,
 877	xfs_nlink_t	nlink,
 878	xfs_dev_t	rdev,
 879	prid_t		prid,		/* project id */
 880	int		okalloc,	/* ok to allocate new space */
 881	xfs_inode_t	**ipp,		/* pointer to inode; it will be
 882					   locked. */
 883	int		*committed)
 884
 885{
 886	xfs_trans_t	*tp;
 887	xfs_trans_t	*ntp;
 888	xfs_inode_t	*ip;
 889	xfs_buf_t	*ialloc_context = NULL;
 890	int		code;
 891	void		*dqinfo;
 892	uint		tflags;
 893
 894	tp = *tpp;
 895	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
 896
 897	/*
 898	 * xfs_ialloc will return a pointer to an incore inode if
 899	 * the Space Manager has an available inode on the free
 900	 * list. Otherwise, it will do an allocation and replenish
 901	 * the freelist.  Since we can only do one allocation per
 902	 * transaction without deadlocks, we will need to commit the
 903	 * current transaction and start a new one.  We will then
 904	 * need to call xfs_ialloc again to get the inode.
 905	 *
 906	 * If xfs_ialloc did an allocation to replenish the freelist,
 907	 * it returns the bp containing the head of the freelist as
 908	 * ialloc_context. We will hold a lock on it across the
 909	 * transaction commit so that no other process can steal
 910	 * the inode(s) that we've just allocated.
 911	 */
 912	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
 913			  &ialloc_context, &ip);
 914
 915	/*
 916	 * Return an error if we were unable to allocate a new inode.
 917	 * This should only happen if we run out of space on disk or
 918	 * encounter a disk error.
 919	 */
 920	if (code) {
 921		*ipp = NULL;
 922		return code;
 923	}
 924	if (!ialloc_context && !ip) {
 925		*ipp = NULL;
 926		return XFS_ERROR(ENOSPC);
 927	}
 928
 929	/*
 930	 * If the AGI buffer is non-NULL, then we were unable to get an
 931	 * inode in one operation.  We need to commit the current
 932	 * transaction and call xfs_ialloc() again.  It is guaranteed
 933	 * to succeed the second time.
 934	 */
 935	if (ialloc_context) {
 936		struct xfs_trans_res tres;
 937
 938		/*
 939		 * Normally, xfs_trans_commit releases all the locks.
 940		 * We call bhold to hang on to the ialloc_context across
 941		 * the commit.  Holding this buffer prevents any other
 942		 * processes from doing any allocations in this
 943		 * allocation group.
 944		 */
 945		xfs_trans_bhold(tp, ialloc_context);
 946		/*
 947		 * Save the log reservation so we can use
 948		 * them in the next transaction.
 949		 */
 950		tres.tr_logres = xfs_trans_get_log_res(tp);
 951		tres.tr_logcount = xfs_trans_get_log_count(tp);
 952
 953		/*
 954		 * We want the quota changes to be associated with the next
 955		 * transaction, NOT this one. So, detach the dqinfo from this
 956		 * and attach it to the next transaction.
 957		 */
 958		dqinfo = NULL;
 959		tflags = 0;
 960		if (tp->t_dqinfo) {
 961			dqinfo = (void *)tp->t_dqinfo;
 962			tp->t_dqinfo = NULL;
 963			tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
 964			tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
 965		}
 966
 967		ntp = xfs_trans_dup(tp);
 968		code = xfs_trans_commit(tp, 0);
 969		tp = ntp;
 970		if (committed != NULL) {
 971			*committed = 1;
 972		}
 973		/*
 974		 * If we get an error during the commit processing,
 975		 * release the buffer that is still held and return
 976		 * to the caller.
 977		 */
 978		if (code) {
 979			xfs_buf_relse(ialloc_context);
 980			if (dqinfo) {
 981				tp->t_dqinfo = dqinfo;
 982				xfs_trans_free_dqinfo(tp);
 983			}
 984			*tpp = ntp;
 985			*ipp = NULL;
 986			return code;
 987		}
 988
 989		/*
 990		 * transaction commit worked ok so we can drop the extra ticket
 991		 * reference that we gained in xfs_trans_dup()
 992		 */
 993		xfs_log_ticket_put(tp->t_ticket);
 994		tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
 995		code = xfs_trans_reserve(tp, &tres, 0, 0);
 996
 997		/*
 998		 * Re-attach the quota info that we detached from prev trx.
 999		 */
1000		if (dqinfo) {
1001			tp->t_dqinfo = dqinfo;
1002			tp->t_flags |= tflags;
1003		}
1004
1005		if (code) {
1006			xfs_buf_relse(ialloc_context);
1007			*tpp = ntp;
1008			*ipp = NULL;
1009			return code;
1010		}
1011		xfs_trans_bjoin(tp, ialloc_context);
1012
1013		/*
1014		 * Call ialloc again. Since we've locked out all
1015		 * other allocations in this allocation group,
1016		 * this call should always succeed.
1017		 */
1018		code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1019				  okalloc, &ialloc_context, &ip);
1020
1021		/*
1022		 * If we get an error at this point, return to the caller
1023		 * so that the current transaction can be aborted.
1024		 */
1025		if (code) {
1026			*tpp = tp;
1027			*ipp = NULL;
1028			return code;
1029		}
1030		ASSERT(!ialloc_context && ip);
1031
1032	} else {
1033		if (committed != NULL)
1034			*committed = 0;
1035	}
1036
1037	*ipp = ip;
1038	*tpp = tp;
1039
1040	return 0;
1041}
1042
1043/*
1044 * Decrement the link count on an inode & log the change.
1045 * If this causes the link count to go to zero, initiate the
1046 * logging activity required to truncate a file.
1047 */
1048int				/* error */
1049xfs_droplink(
1050	xfs_trans_t *tp,
1051	xfs_inode_t *ip)
1052{
1053	int	error;
1054
1055	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1056
1057	ASSERT (ip->i_d.di_nlink > 0);
1058	ip->i_d.di_nlink--;
1059	drop_nlink(VFS_I(ip));
1060	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1061
1062	error = 0;
1063	if (ip->i_d.di_nlink == 0) {
1064		/*
1065		 * We're dropping the last link to this file.
1066		 * Move the on-disk inode to the AGI unlinked list.
1067		 * From xfs_inactive() we will pull the inode from
1068		 * the list and free it.
1069		 */
1070		error = xfs_iunlink(tp, ip);
1071	}
1072	return error;
1073}
1074
1075/*
1076 * This gets called when the inode's version needs to be changed from 1 to 2.
1077 * Currently this happens when the nlink field overflows the old 16-bit value
1078 * or when chproj is called to change the project for the first time.
1079 * As a side effect the superblock version will also get rev'd
1080 * to contain the NLINK bit.
1081 */
1082void
1083xfs_bump_ino_vers2(
1084	xfs_trans_t	*tp,
1085	xfs_inode_t	*ip)
1086{
1087	xfs_mount_t	*mp;
1088
1089	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1090	ASSERT(ip->i_d.di_version == 1);
1091
1092	ip->i_d.di_version = 2;
1093	ip->i_d.di_onlink = 0;
1094	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
1095	mp = tp->t_mountp;
1096	if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
1097		spin_lock(&mp->m_sb_lock);
1098		if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
1099			xfs_sb_version_addnlink(&mp->m_sb);
1100			spin_unlock(&mp->m_sb_lock);
1101			xfs_mod_sb(tp, XFS_SB_VERSIONNUM);
1102		} else {
1103			spin_unlock(&mp->m_sb_lock);
1104		}
1105	}
1106	/* Caller must log the inode */
1107}
1108
1109/*
1110 * Increment the link count on an inode & log the change.
1111 */
1112int
1113xfs_bumplink(
1114	xfs_trans_t *tp,
1115	xfs_inode_t *ip)
1116{
1117	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1118
1119	ASSERT(ip->i_d.di_nlink > 0 || (VFS_I(ip)->i_state & I_LINKABLE));
1120	ip->i_d.di_nlink++;
1121	inc_nlink(VFS_I(ip));
1122	if ((ip->i_d.di_version == 1) &&
1123	    (ip->i_d.di_nlink > XFS_MAXLINK_1)) {
1124		/*
1125		 * The inode has increased its number of links beyond
1126		 * what can fit in an old format inode.  It now needs
1127		 * to be converted to a version 2 inode with a 32 bit
1128		 * link count.  If this is the first inode in the file
1129		 * system to do this, then we need to bump the superblock
1130		 * version number as well.
1131		 */
1132		xfs_bump_ino_vers2(tp, ip);
1133	}
1134
1135	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1136	return 0;
1137}
1138
1139int
1140xfs_create(
1141	xfs_inode_t		*dp,
1142	struct xfs_name		*name,
1143	umode_t			mode,
1144	xfs_dev_t		rdev,
1145	xfs_inode_t		**ipp)
1146{
1147	int			is_dir = S_ISDIR(mode);
1148	struct xfs_mount	*mp = dp->i_mount;
1149	struct xfs_inode	*ip = NULL;
1150	struct xfs_trans	*tp = NULL;
1151	int			error;
1152	xfs_bmap_free_t		free_list;
1153	xfs_fsblock_t		first_block;
1154	bool                    unlock_dp_on_error = false;
1155	uint			cancel_flags;
1156	int			committed;
1157	prid_t			prid;
1158	struct xfs_dquot	*udqp = NULL;
1159	struct xfs_dquot	*gdqp = NULL;
1160	struct xfs_dquot	*pdqp = NULL;
1161	struct xfs_trans_res	tres;
1162	uint			resblks;
1163
1164	trace_xfs_create(dp, name);
1165
1166	if (XFS_FORCED_SHUTDOWN(mp))
1167		return XFS_ERROR(EIO);
1168
1169	prid = xfs_get_initial_prid(dp);
1170
1171	/*
1172	 * Make sure that we have allocated dquot(s) on disk.
1173	 */
1174	error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1175					xfs_kgid_to_gid(current_fsgid()), prid,
1176					XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1177					&udqp, &gdqp, &pdqp);
1178	if (error)
1179		return error;
1180
1181	if (is_dir) {
1182		rdev = 0;
1183		resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1184		tres.tr_logres = M_RES(mp)->tr_mkdir.tr_logres;
1185		tres.tr_logcount = XFS_MKDIR_LOG_COUNT;
1186		tp = xfs_trans_alloc(mp, XFS_TRANS_MKDIR);
1187	} else {
1188		resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1189		tres.tr_logres = M_RES(mp)->tr_create.tr_logres;
1190		tres.tr_logcount = XFS_CREATE_LOG_COUNT;
1191		tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE);
1192	}
1193
1194	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1195
1196	/*
1197	 * Initially assume that the file does not exist and
1198	 * reserve the resources for that case.  If that is not
1199	 * the case we'll drop the one we have and get a more
1200	 * appropriate transaction later.
1201	 */
1202	tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
1203	error = xfs_trans_reserve(tp, &tres, resblks, 0);
1204	if (error == ENOSPC) {
1205		/* flush outstanding delalloc blocks and retry */
1206		xfs_flush_inodes(mp);
1207		error = xfs_trans_reserve(tp, &tres, resblks, 0);
1208	}
1209	if (error == ENOSPC) {
1210		/* No space at all so try a "no-allocation" reservation */
1211		resblks = 0;
1212		error = xfs_trans_reserve(tp, &tres, 0, 0);
1213	}
1214	if (error) {
1215		cancel_flags = 0;
1216		goto out_trans_cancel;
1217	}
 
 
1218
1219	xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1220	unlock_dp_on_error = true;
1221
1222	xfs_bmap_init(&free_list, &first_block);
1223
1224	/*
1225	 * Reserve disk quota and the inode.
1226	 */
1227	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1228						pdqp, resblks, 1, 0);
1229	if (error)
1230		goto out_trans_cancel;
1231
1232	error = xfs_dir_canenter(tp, dp, name, resblks);
1233	if (error)
1234		goto out_trans_cancel;
 
 
1235
1236	/*
1237	 * A newly created regular or special file just has one directory
1238	 * entry pointing to them, but a directory also the "." entry
1239	 * pointing to itself.
1240	 */
1241	error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
1242			       prid, resblks > 0, &ip, &committed);
1243	if (error) {
1244		if (error == ENOSPC)
1245			goto out_trans_cancel;
1246		goto out_trans_abort;
1247	}
1248
1249	/*
1250	 * Now we join the directory inode to the transaction.  We do not do it
1251	 * earlier because xfs_dir_ialloc might commit the previous transaction
1252	 * (and release all the locks).  An error from here on will result in
1253	 * the transaction cancel unlocking dp so don't do it explicitly in the
1254	 * error path.
1255	 */
1256	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1257	unlock_dp_on_error = false;
1258
1259	error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1260					&first_block, &free_list, resblks ?
1261					resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1262	if (error) {
1263		ASSERT(error != ENOSPC);
1264		goto out_trans_abort;
1265	}
1266	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1267	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1268
1269	if (is_dir) {
1270		error = xfs_dir_init(tp, ip, dp);
1271		if (error)
1272			goto out_bmap_cancel;
1273
1274		error = xfs_bumplink(tp, dp);
1275		if (error)
1276			goto out_bmap_cancel;
1277	}
1278
1279	/*
1280	 * If this is a synchronous mount, make sure that the
1281	 * create transaction goes to disk before returning to
1282	 * the user.
1283	 */
1284	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1285		xfs_trans_set_sync(tp);
1286
1287	/*
1288	 * Attach the dquot(s) to the inodes and modify them incore.
1289	 * These ids of the inode couldn't have changed since the new
1290	 * inode has been locked ever since it was created.
1291	 */
1292	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1293
1294	error = xfs_bmap_finish(&tp, &free_list, &committed);
1295	if (error)
1296		goto out_bmap_cancel;
1297
1298	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1299	if (error)
1300		goto out_release_inode;
1301
1302	xfs_qm_dqrele(udqp);
1303	xfs_qm_dqrele(gdqp);
1304	xfs_qm_dqrele(pdqp);
1305
1306	*ipp = ip;
1307	return 0;
1308
1309 out_bmap_cancel:
1310	xfs_bmap_cancel(&free_list);
1311 out_trans_abort:
1312	cancel_flags |= XFS_TRANS_ABORT;
1313 out_trans_cancel:
1314	xfs_trans_cancel(tp, cancel_flags);
1315 out_release_inode:
1316	/*
1317	 * Wait until after the current transaction is aborted to
1318	 * release the inode.  This prevents recursive transactions
1319	 * and deadlocks from xfs_inactive.
1320	 */
1321	if (ip)
 
1322		IRELE(ip);
 
1323
1324	xfs_qm_dqrele(udqp);
1325	xfs_qm_dqrele(gdqp);
1326	xfs_qm_dqrele(pdqp);
1327
1328	if (unlock_dp_on_error)
1329		xfs_iunlock(dp, XFS_ILOCK_EXCL);
1330	return error;
1331}
1332
1333int
1334xfs_create_tmpfile(
1335	struct xfs_inode	*dp,
1336	struct dentry		*dentry,
1337	umode_t			mode,
1338	struct xfs_inode	**ipp)
1339{
1340	struct xfs_mount	*mp = dp->i_mount;
1341	struct xfs_inode	*ip = NULL;
1342	struct xfs_trans	*tp = NULL;
1343	int			error;
1344	uint			cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1345	prid_t                  prid;
1346	struct xfs_dquot	*udqp = NULL;
1347	struct xfs_dquot	*gdqp = NULL;
1348	struct xfs_dquot	*pdqp = NULL;
1349	struct xfs_trans_res	*tres;
1350	uint			resblks;
1351
1352	if (XFS_FORCED_SHUTDOWN(mp))
1353		return XFS_ERROR(EIO);
1354
1355	prid = xfs_get_initial_prid(dp);
1356
1357	/*
1358	 * Make sure that we have allocated dquot(s) on disk.
1359	 */
1360	error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1361				xfs_kgid_to_gid(current_fsgid()), prid,
1362				XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1363				&udqp, &gdqp, &pdqp);
1364	if (error)
1365		return error;
1366
1367	resblks = XFS_IALLOC_SPACE_RES(mp);
1368	tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE_TMPFILE);
1369
1370	tres = &M_RES(mp)->tr_create_tmpfile;
1371	error = xfs_trans_reserve(tp, tres, resblks, 0);
1372	if (error == ENOSPC) {
 
1373		/* No space at all so try a "no-allocation" reservation */
1374		resblks = 0;
1375		error = xfs_trans_reserve(tp, tres, 0, 0);
1376	}
1377	if (error) {
1378		cancel_flags = 0;
1379		goto out_trans_cancel;
1380	}
 
 
1381
1382	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1383						pdqp, resblks, 1, 0);
1384	if (error)
1385		goto out_trans_cancel;
1386
1387	error = xfs_dir_ialloc(&tp, dp, mode, 1, 0,
1388				prid, resblks > 0, &ip, NULL);
1389	if (error) {
1390		if (error == ENOSPC)
1391			goto out_trans_cancel;
1392		goto out_trans_abort;
1393	}
1394
1395	if (mp->m_flags & XFS_MOUNT_WSYNC)
1396		xfs_trans_set_sync(tp);
1397
1398	/*
1399	 * Attach the dquot(s) to the inodes and modify them incore.
1400	 * These ids of the inode couldn't have changed since the new
1401	 * inode has been locked ever since it was created.
1402	 */
1403	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1404
1405	ip->i_d.di_nlink--;
1406	error = xfs_iunlink(tp, ip);
1407	if (error)
1408		goto out_trans_abort;
1409
1410	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1411	if (error)
1412		goto out_release_inode;
1413
1414	xfs_qm_dqrele(udqp);
1415	xfs_qm_dqrele(gdqp);
1416	xfs_qm_dqrele(pdqp);
1417
1418	*ipp = ip;
1419	return 0;
1420
1421 out_trans_abort:
1422	cancel_flags |= XFS_TRANS_ABORT;
1423 out_trans_cancel:
1424	xfs_trans_cancel(tp, cancel_flags);
1425 out_release_inode:
1426	/*
1427	 * Wait until after the current transaction is aborted to
1428	 * release the inode.  This prevents recursive transactions
1429	 * and deadlocks from xfs_inactive.
1430	 */
1431	if (ip)
 
1432		IRELE(ip);
 
1433
1434	xfs_qm_dqrele(udqp);
1435	xfs_qm_dqrele(gdqp);
1436	xfs_qm_dqrele(pdqp);
1437
1438	return error;
1439}
1440
1441int
1442xfs_link(
1443	xfs_inode_t		*tdp,
1444	xfs_inode_t		*sip,
1445	struct xfs_name		*target_name)
1446{
1447	xfs_mount_t		*mp = tdp->i_mount;
1448	xfs_trans_t		*tp;
1449	int			error;
1450	xfs_bmap_free_t         free_list;
1451	xfs_fsblock_t           first_block;
1452	int			cancel_flags;
1453	int			committed;
1454	int			resblks;
1455
1456	trace_xfs_link(tdp, target_name);
1457
1458	ASSERT(!S_ISDIR(sip->i_d.di_mode));
1459
1460	if (XFS_FORCED_SHUTDOWN(mp))
1461		return XFS_ERROR(EIO);
1462
1463	error = xfs_qm_dqattach(sip, 0);
1464	if (error)
1465		goto std_return;
1466
1467	error = xfs_qm_dqattach(tdp, 0);
1468	if (error)
1469		goto std_return;
1470
1471	tp = xfs_trans_alloc(mp, XFS_TRANS_LINK);
1472	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1473	resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1474	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, resblks, 0);
1475	if (error == ENOSPC) {
1476		resblks = 0;
1477		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, 0, 0);
1478	}
1479	if (error) {
1480		cancel_flags = 0;
1481		goto error_return;
1482	}
 
 
1483
1484	xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
1485
1486	xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1487	xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1488
1489	/*
1490	 * If we are using project inheritance, we only allow hard link
1491	 * creation in our tree when the project IDs are the same; else
1492	 * the tree quota mechanism could be circumvented.
1493	 */
1494	if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1495		     (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1496		error = XFS_ERROR(EXDEV);
1497		goto error_return;
1498	}
1499
1500	error = xfs_dir_canenter(tp, tdp, target_name, resblks);
1501	if (error)
1502		goto error_return;
 
 
1503
1504	xfs_bmap_init(&free_list, &first_block);
1505
1506	if (sip->i_d.di_nlink == 0) {
 
 
 
1507		error = xfs_iunlink_remove(tp, sip);
1508		if (error)
1509			goto abort_return;
1510	}
1511
1512	error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1513					&first_block, &free_list, resblks);
1514	if (error)
1515		goto abort_return;
1516	xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1517	xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1518
1519	error = xfs_bumplink(tp, sip);
1520	if (error)
1521		goto abort_return;
1522
1523	/*
1524	 * If this is a synchronous mount, make sure that the
1525	 * link transaction goes to disk before returning to
1526	 * the user.
1527	 */
1528	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
1529		xfs_trans_set_sync(tp);
1530	}
1531
1532	error = xfs_bmap_finish (&tp, &free_list, &committed);
1533	if (error) {
1534		xfs_bmap_cancel(&free_list);
1535		goto abort_return;
1536	}
1537
1538	return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1539
1540 abort_return:
1541	cancel_flags |= XFS_TRANS_ABORT;
1542 error_return:
1543	xfs_trans_cancel(tp, cancel_flags);
1544 std_return:
1545	return error;
1546}
1547
1548/*
1549 * Free up the underlying blocks past new_size.  The new size must be smaller
1550 * than the current size.  This routine can be used both for the attribute and
1551 * data fork, and does not modify the inode size, which is left to the caller.
1552 *
1553 * The transaction passed to this routine must have made a permanent log
1554 * reservation of at least XFS_ITRUNCATE_LOG_RES.  This routine may commit the
1555 * given transaction and start new ones, so make sure everything involved in
1556 * the transaction is tidy before calling here.  Some transaction will be
1557 * returned to the caller to be committed.  The incoming transaction must
1558 * already include the inode, and both inode locks must be held exclusively.
1559 * The inode must also be "held" within the transaction.  On return the inode
1560 * will be "held" within the returned transaction.  This routine does NOT
1561 * require any disk space to be reserved for it within the transaction.
1562 *
1563 * If we get an error, we must return with the inode locked and linked into the
1564 * current transaction. This keeps things simple for the higher level code,
1565 * because it always knows that the inode is locked and held in the transaction
1566 * that returns to it whether errors occur or not.  We don't mark the inode
1567 * dirty on error so that transactions can be easily aborted if possible.
1568 */
1569int
1570xfs_itruncate_extents(
1571	struct xfs_trans	**tpp,
1572	struct xfs_inode	*ip,
1573	int			whichfork,
1574	xfs_fsize_t		new_size)
1575{
1576	struct xfs_mount	*mp = ip->i_mount;
1577	struct xfs_trans	*tp = *tpp;
1578	struct xfs_trans	*ntp;
1579	xfs_bmap_free_t		free_list;
1580	xfs_fsblock_t		first_block;
1581	xfs_fileoff_t		first_unmap_block;
1582	xfs_fileoff_t		last_block;
1583	xfs_filblks_t		unmap_len;
1584	int			committed;
1585	int			error = 0;
1586	int			done = 0;
1587
1588	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1589	ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1590	       xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1591	ASSERT(new_size <= XFS_ISIZE(ip));
1592	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1593	ASSERT(ip->i_itemp != NULL);
1594	ASSERT(ip->i_itemp->ili_lock_flags == 0);
1595	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1596
1597	trace_xfs_itruncate_extents_start(ip, new_size);
1598
1599	/*
1600	 * Since it is possible for space to become allocated beyond
1601	 * the end of the file (in a crash where the space is allocated
1602	 * but the inode size is not yet updated), simply remove any
1603	 * blocks which show up between the new EOF and the maximum
1604	 * possible file size.  If the first block to be removed is
1605	 * beyond the maximum file size (ie it is the same as last_block),
1606	 * then there is nothing to do.
1607	 */
1608	first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1609	last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1610	if (first_unmap_block == last_block)
1611		return 0;
1612
1613	ASSERT(first_unmap_block < last_block);
1614	unmap_len = last_block - first_unmap_block + 1;
1615	while (!done) {
1616		xfs_bmap_init(&free_list, &first_block);
1617		error = xfs_bunmapi(tp, ip,
1618				    first_unmap_block, unmap_len,
1619				    xfs_bmapi_aflag(whichfork),
1620				    XFS_ITRUNC_MAX_EXTENTS,
1621				    &first_block, &free_list,
1622				    &done);
1623		if (error)
1624			goto out_bmap_cancel;
1625
1626		/*
1627		 * Duplicate the transaction that has the permanent
1628		 * reservation and commit the old transaction.
1629		 */
1630		error = xfs_bmap_finish(&tp, &free_list, &committed);
1631		if (committed)
1632			xfs_trans_ijoin(tp, ip, 0);
1633		if (error)
1634			goto out_bmap_cancel;
1635
1636		if (committed) {
1637			/*
1638			 * Mark the inode dirty so it will be logged and
1639			 * moved forward in the log as part of every commit.
1640			 */
1641			xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1642		}
1643
1644		ntp = xfs_trans_dup(tp);
1645		error = xfs_trans_commit(tp, 0);
1646		tp = ntp;
1647
1648		xfs_trans_ijoin(tp, ip, 0);
1649
1650		if (error)
1651			goto out;
 
1652
1653		/*
1654		 * Transaction commit worked ok so we can drop the extra ticket
1655		 * reference that we gained in xfs_trans_dup()
1656		 */
1657		xfs_log_ticket_put(tp->t_ticket);
1658		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
1659		if (error)
1660			goto out;
 
 
 
 
1661	}
1662
1663	/*
1664	 * Always re-log the inode so that our permanent transaction can keep
1665	 * on rolling it forward in the log.
1666	 */
1667	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1668
1669	trace_xfs_itruncate_extents_end(ip, new_size);
1670
1671out:
1672	*tpp = tp;
1673	return error;
1674out_bmap_cancel:
1675	/*
1676	 * If the bunmapi call encounters an error, return to the caller where
1677	 * the transaction can be properly aborted.  We just need to make sure
1678	 * we're not holding any resources that we were not when we came in.
1679	 */
1680	xfs_bmap_cancel(&free_list);
1681	goto out;
1682}
1683
1684int
1685xfs_release(
1686	xfs_inode_t	*ip)
1687{
1688	xfs_mount_t	*mp = ip->i_mount;
1689	int		error;
1690
1691	if (!S_ISREG(ip->i_d.di_mode) || (ip->i_d.di_mode == 0))
1692		return 0;
1693
1694	/* If this is a read-only mount, don't do this (would generate I/O) */
1695	if (mp->m_flags & XFS_MOUNT_RDONLY)
1696		return 0;
1697
1698	if (!XFS_FORCED_SHUTDOWN(mp)) {
1699		int truncated;
1700
1701		/*
1702		 * If we are using filestreams, and we have an unlinked
1703		 * file that we are processing the last close on, then nothing
1704		 * will be able to reopen and write to this file. Purge this
1705		 * inode from the filestreams cache so that it doesn't delay
1706		 * teardown of the inode.
1707		 */
1708		if ((ip->i_d.di_nlink == 0) && xfs_inode_is_filestream(ip))
1709			xfs_filestream_deassociate(ip);
1710
1711		/*
1712		 * If we previously truncated this file and removed old data
1713		 * in the process, we want to initiate "early" writeout on
1714		 * the last close.  This is an attempt to combat the notorious
1715		 * NULL files problem which is particularly noticeable from a
1716		 * truncate down, buffered (re-)write (delalloc), followed by
1717		 * a crash.  What we are effectively doing here is
1718		 * significantly reducing the time window where we'd otherwise
1719		 * be exposed to that problem.
1720		 */
1721		truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1722		if (truncated) {
1723			xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1724			if (VN_DIRTY(VFS_I(ip)) && ip->i_delayed_blks > 0) {
1725				error = -filemap_flush(VFS_I(ip)->i_mapping);
1726				if (error)
1727					return error;
1728			}
1729		}
1730	}
1731
1732	if (ip->i_d.di_nlink == 0)
1733		return 0;
1734
1735	if (xfs_can_free_eofblocks(ip, false)) {
1736
1737		/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1738		 * If we can't get the iolock just skip truncating the blocks
1739		 * past EOF because we could deadlock with the mmap_sem
1740		 * otherwise.  We'll get another chance to drop them once the
1741		 * last reference to the inode is dropped, so we'll never leak
1742		 * blocks permanently.
1743		 *
1744		 * Further, check if the inode is being opened, written and
1745		 * closed frequently and we have delayed allocation blocks
1746		 * outstanding (e.g. streaming writes from the NFS server),
1747		 * truncating the blocks past EOF will cause fragmentation to
1748		 * occur.
1749		 *
1750		 * In this case don't do the truncation, either, but we have to
1751		 * be careful how we detect this case. Blocks beyond EOF show
1752		 * up as i_delayed_blks even when the inode is clean, so we
1753		 * need to truncate them away first before checking for a dirty
1754		 * release. Hence on the first dirty close we will still remove
1755		 * the speculative allocation, but after that we will leave it
1756		 * in place.
1757		 */
1758		if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1759			return 0;
1760
1761		error = xfs_free_eofblocks(mp, ip, true);
1762		if (error && error != EAGAIN)
1763			return error;
1764
1765		/* delalloc blocks after truncation means it really is dirty */
1766		if (ip->i_delayed_blks)
1767			xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1768	}
1769	return 0;
1770}
1771
1772/*
1773 * xfs_inactive_truncate
1774 *
1775 * Called to perform a truncate when an inode becomes unlinked.
1776 */
1777STATIC int
1778xfs_inactive_truncate(
1779	struct xfs_inode *ip)
1780{
1781	struct xfs_mount	*mp = ip->i_mount;
1782	struct xfs_trans	*tp;
1783	int			error;
1784
1785	tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
1786	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
1787	if (error) {
1788		ASSERT(XFS_FORCED_SHUTDOWN(mp));
1789		xfs_trans_cancel(tp, 0);
1790		return error;
1791	}
1792
1793	xfs_ilock(ip, XFS_ILOCK_EXCL);
1794	xfs_trans_ijoin(tp, ip, 0);
1795
1796	/*
1797	 * Log the inode size first to prevent stale data exposure in the event
1798	 * of a system crash before the truncate completes. See the related
1799	 * comment in xfs_setattr_size() for details.
1800	 */
1801	ip->i_d.di_size = 0;
1802	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1803
1804	error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1805	if (error)
1806		goto error_trans_cancel;
1807
1808	ASSERT(ip->i_d.di_nextents == 0);
1809
1810	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1811	if (error)
1812		goto error_unlock;
1813
1814	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1815	return 0;
1816
1817error_trans_cancel:
1818	xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1819error_unlock:
1820	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1821	return error;
1822}
1823
1824/*
1825 * xfs_inactive_ifree()
1826 *
1827 * Perform the inode free when an inode is unlinked.
1828 */
1829STATIC int
1830xfs_inactive_ifree(
1831	struct xfs_inode *ip)
1832{
1833	xfs_bmap_free_t		free_list;
1834	xfs_fsblock_t		first_block;
1835	int			committed;
1836	struct xfs_mount	*mp = ip->i_mount;
1837	struct xfs_trans	*tp;
1838	int			error;
1839
1840	tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
1841	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ifree, 0, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1842	if (error) {
1843		ASSERT(XFS_FORCED_SHUTDOWN(mp));
1844		xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES);
 
 
 
 
 
1845		return error;
1846	}
1847
1848	xfs_ilock(ip, XFS_ILOCK_EXCL);
1849	xfs_trans_ijoin(tp, ip, 0);
1850
1851	xfs_bmap_init(&free_list, &first_block);
1852	error = xfs_ifree(tp, ip, &free_list);
1853	if (error) {
1854		/*
1855		 * If we fail to free the inode, shut down.  The cancel
1856		 * might do that, we need to make sure.  Otherwise the
1857		 * inode might be lost for a long time or forever.
1858		 */
1859		if (!XFS_FORCED_SHUTDOWN(mp)) {
1860			xfs_notice(mp, "%s: xfs_ifree returned error %d",
1861				__func__, error);
1862			xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1863		}
1864		xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
1865		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1866		return error;
1867	}
1868
1869	/*
1870	 * Credit the quota account(s). The inode is gone.
1871	 */
1872	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1873
1874	/*
1875	 * Just ignore errors at this point.  There is nothing we can
1876	 * do except to try to keep going. Make sure it's not a silent
1877	 * error.
1878	 */
1879	error = xfs_bmap_finish(&tp,  &free_list, &committed);
1880	if (error)
1881		xfs_notice(mp, "%s: xfs_bmap_finish returned error %d",
1882			__func__, error);
1883	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
 
 
1884	if (error)
1885		xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1886			__func__, error);
1887
1888	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1889	return 0;
1890}
1891
1892/*
1893 * xfs_inactive
1894 *
1895 * This is called when the vnode reference count for the vnode
1896 * goes to zero.  If the file has been unlinked, then it must
1897 * now be truncated.  Also, we clear all of the read-ahead state
1898 * kept for the inode here since the file is now closed.
1899 */
1900void
1901xfs_inactive(
1902	xfs_inode_t	*ip)
1903{
1904	struct xfs_mount	*mp;
1905	int			error;
1906	int			truncate = 0;
1907
1908	/*
1909	 * If the inode is already free, then there can be nothing
1910	 * to clean up here.
1911	 */
1912	if (ip->i_d.di_mode == 0) {
1913		ASSERT(ip->i_df.if_real_bytes == 0);
1914		ASSERT(ip->i_df.if_broot_bytes == 0);
1915		return;
1916	}
1917
1918	mp = ip->i_mount;
 
1919
1920	/* If this is a read-only mount, don't do this (would generate I/O) */
1921	if (mp->m_flags & XFS_MOUNT_RDONLY)
1922		return;
1923
1924	if (ip->i_d.di_nlink != 0) {
1925		/*
1926		 * force is true because we are evicting an inode from the
1927		 * cache. Post-eof blocks must be freed, lest we end up with
1928		 * broken free space accounting.
1929		 */
1930		if (xfs_can_free_eofblocks(ip, true))
1931			xfs_free_eofblocks(mp, ip, false);
 
 
 
1932
1933		return;
1934	}
1935
1936	if (S_ISREG(ip->i_d.di_mode) &&
1937	    (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1938	     ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1939		truncate = 1;
1940
1941	error = xfs_qm_dqattach(ip, 0);
1942	if (error)
1943		return;
1944
1945	if (S_ISLNK(ip->i_d.di_mode))
1946		error = xfs_inactive_symlink(ip);
1947	else if (truncate)
1948		error = xfs_inactive_truncate(ip);
1949	if (error)
1950		return;
1951
1952	/*
1953	 * If there are attributes associated with the file then blow them away
1954	 * now.  The code calls a routine that recursively deconstructs the
1955	 * attribute fork.  We need to just commit the current transaction
1956	 * because we can't use it for xfs_attr_inactive().
1957	 */
1958	if (ip->i_d.di_anextents > 0) {
1959		ASSERT(ip->i_d.di_forkoff != 0);
1960
1961		error = xfs_attr_inactive(ip);
1962		if (error)
1963			return;
1964	}
1965
1966	if (ip->i_afp)
1967		xfs_idestroy_fork(ip, XFS_ATTR_FORK);
1968
1969	ASSERT(ip->i_d.di_anextents == 0);
 
1970
1971	/*
1972	 * Free the inode.
1973	 */
1974	error = xfs_inactive_ifree(ip);
1975	if (error)
1976		return;
1977
1978	/*
1979	 * Release the dquots held by inode, if any.
1980	 */
1981	xfs_qm_dqdetach(ip);
1982}
1983
1984/*
1985 * This is called when the inode's link count goes to 0.
1986 * We place the on-disk inode on a list in the AGI.  It
1987 * will be pulled from this list when the inode is freed.
 
 
 
 
 
1988 */
1989int
1990xfs_iunlink(
1991	xfs_trans_t	*tp,
1992	xfs_inode_t	*ip)
1993{
1994	xfs_mount_t	*mp;
1995	xfs_agi_t	*agi;
1996	xfs_dinode_t	*dip;
1997	xfs_buf_t	*agibp;
1998	xfs_buf_t	*ibp;
1999	xfs_agino_t	agino;
2000	short		bucket_index;
2001	int		offset;
2002	int		error;
2003
2004	ASSERT(ip->i_d.di_nlink == 0);
2005	ASSERT(ip->i_d.di_mode != 0);
2006
2007	mp = tp->t_mountp;
2008
2009	/*
2010	 * Get the agi buffer first.  It ensures lock ordering
2011	 * on the list.
2012	 */
2013	error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
2014	if (error)
2015		return error;
2016	agi = XFS_BUF_TO_AGI(agibp);
2017
2018	/*
2019	 * Get the index into the agi hash table for the
2020	 * list this inode will go on.
2021	 */
2022	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2023	ASSERT(agino != 0);
2024	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2025	ASSERT(agi->agi_unlinked[bucket_index]);
2026	ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
2027
2028	if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
2029		/*
2030		 * There is already another inode in the bucket we need
2031		 * to add ourselves to.  Add us at the front of the list.
2032		 * Here we put the head pointer into our next pointer,
2033		 * and then we fall through to point the head at us.
2034		 */
2035		error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2036				       0, 0);
2037		if (error)
2038			return error;
2039
2040		ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
2041		dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
2042		offset = ip->i_imap.im_boffset +
2043			offsetof(xfs_dinode_t, di_next_unlinked);
2044
2045		/* need to recalc the inode CRC if appropriate */
2046		xfs_dinode_calc_crc(mp, dip);
2047
2048		xfs_trans_inode_buf(tp, ibp);
2049		xfs_trans_log_buf(tp, ibp, offset,
2050				  (offset + sizeof(xfs_agino_t) - 1));
2051		xfs_inobp_check(mp, ibp);
2052	}
2053
2054	/*
2055	 * Point the bucket head pointer at the inode being inserted.
2056	 */
2057	ASSERT(agino != 0);
2058	agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
2059	offset = offsetof(xfs_agi_t, agi_unlinked) +
2060		(sizeof(xfs_agino_t) * bucket_index);
2061	xfs_trans_log_buf(tp, agibp, offset,
2062			  (offset + sizeof(xfs_agino_t) - 1));
2063	return 0;
2064}
2065
2066/*
2067 * Pull the on-disk inode from the AGI unlinked list.
2068 */
2069STATIC int
2070xfs_iunlink_remove(
2071	xfs_trans_t	*tp,
2072	xfs_inode_t	*ip)
2073{
2074	xfs_ino_t	next_ino;
2075	xfs_mount_t	*mp;
2076	xfs_agi_t	*agi;
2077	xfs_dinode_t	*dip;
2078	xfs_buf_t	*agibp;
2079	xfs_buf_t	*ibp;
2080	xfs_agnumber_t	agno;
2081	xfs_agino_t	agino;
2082	xfs_agino_t	next_agino;
2083	xfs_buf_t	*last_ibp;
2084	xfs_dinode_t	*last_dip = NULL;
2085	short		bucket_index;
2086	int		offset, last_offset = 0;
2087	int		error;
2088
2089	mp = tp->t_mountp;
2090	agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2091
2092	/*
2093	 * Get the agi buffer first.  It ensures lock ordering
2094	 * on the list.
2095	 */
2096	error = xfs_read_agi(mp, tp, agno, &agibp);
2097	if (error)
2098		return error;
2099
2100	agi = XFS_BUF_TO_AGI(agibp);
2101
2102	/*
2103	 * Get the index into the agi hash table for the
2104	 * list this inode will go on.
2105	 */
2106	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2107	ASSERT(agino != 0);
2108	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2109	ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
2110	ASSERT(agi->agi_unlinked[bucket_index]);
2111
2112	if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
2113		/*
2114		 * We're at the head of the list.  Get the inode's on-disk
2115		 * buffer to see if there is anyone after us on the list.
2116		 * Only modify our next pointer if it is not already NULLAGINO.
2117		 * This saves us the overhead of dealing with the buffer when
2118		 * there is no need to change it.
2119		 */
2120		error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2121				       0, 0);
2122		if (error) {
2123			xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2124				__func__, error);
2125			return error;
2126		}
2127		next_agino = be32_to_cpu(dip->di_next_unlinked);
2128		ASSERT(next_agino != 0);
2129		if (next_agino != NULLAGINO) {
2130			dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2131			offset = ip->i_imap.im_boffset +
2132				offsetof(xfs_dinode_t, di_next_unlinked);
2133
2134			/* need to recalc the inode CRC if appropriate */
2135			xfs_dinode_calc_crc(mp, dip);
2136
2137			xfs_trans_inode_buf(tp, ibp);
2138			xfs_trans_log_buf(tp, ibp, offset,
2139					  (offset + sizeof(xfs_agino_t) - 1));
2140			xfs_inobp_check(mp, ibp);
2141		} else {
2142			xfs_trans_brelse(tp, ibp);
2143		}
2144		/*
2145		 * Point the bucket head pointer at the next inode.
2146		 */
2147		ASSERT(next_agino != 0);
2148		ASSERT(next_agino != agino);
2149		agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
2150		offset = offsetof(xfs_agi_t, agi_unlinked) +
2151			(sizeof(xfs_agino_t) * bucket_index);
2152		xfs_trans_log_buf(tp, agibp, offset,
2153				  (offset + sizeof(xfs_agino_t) - 1));
2154	} else {
2155		/*
2156		 * We need to search the list for the inode being freed.
2157		 */
2158		next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2159		last_ibp = NULL;
2160		while (next_agino != agino) {
2161			struct xfs_imap	imap;
2162
2163			if (last_ibp)
2164				xfs_trans_brelse(tp, last_ibp);
2165
2166			imap.im_blkno = 0;
2167			next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
2168
2169			error = xfs_imap(mp, tp, next_ino, &imap, 0);
2170			if (error) {
2171				xfs_warn(mp,
2172	"%s: xfs_imap returned error %d.",
2173					 __func__, error);
2174				return error;
2175			}
2176
2177			error = xfs_imap_to_bp(mp, tp, &imap, &last_dip,
2178					       &last_ibp, 0, 0);
2179			if (error) {
2180				xfs_warn(mp,
2181	"%s: xfs_imap_to_bp returned error %d.",
2182					__func__, error);
2183				return error;
2184			}
2185
2186			last_offset = imap.im_boffset;
2187			next_agino = be32_to_cpu(last_dip->di_next_unlinked);
2188			ASSERT(next_agino != NULLAGINO);
2189			ASSERT(next_agino != 0);
2190		}
2191
2192		/*
2193		 * Now last_ibp points to the buffer previous to us on the
2194		 * unlinked list.  Pull us from the list.
2195		 */
2196		error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2197				       0, 0);
2198		if (error) {
2199			xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
2200				__func__, error);
2201			return error;
2202		}
2203		next_agino = be32_to_cpu(dip->di_next_unlinked);
2204		ASSERT(next_agino != 0);
2205		ASSERT(next_agino != agino);
2206		if (next_agino != NULLAGINO) {
2207			dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2208			offset = ip->i_imap.im_boffset +
2209				offsetof(xfs_dinode_t, di_next_unlinked);
2210
2211			/* need to recalc the inode CRC if appropriate */
2212			xfs_dinode_calc_crc(mp, dip);
2213
2214			xfs_trans_inode_buf(tp, ibp);
2215			xfs_trans_log_buf(tp, ibp, offset,
2216					  (offset + sizeof(xfs_agino_t) - 1));
2217			xfs_inobp_check(mp, ibp);
2218		} else {
2219			xfs_trans_brelse(tp, ibp);
2220		}
2221		/*
2222		 * Point the previous inode on the list to the next inode.
2223		 */
2224		last_dip->di_next_unlinked = cpu_to_be32(next_agino);
2225		ASSERT(next_agino != 0);
2226		offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
2227
2228		/* need to recalc the inode CRC if appropriate */
2229		xfs_dinode_calc_crc(mp, last_dip);
2230
2231		xfs_trans_inode_buf(tp, last_ibp);
2232		xfs_trans_log_buf(tp, last_ibp, offset,
2233				  (offset + sizeof(xfs_agino_t) - 1));
2234		xfs_inobp_check(mp, last_ibp);
2235	}
2236	return 0;
2237}
2238
2239/*
2240 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2241 * inodes that are in memory - they all must be marked stale and attached to
2242 * the cluster buffer.
2243 */
2244STATIC int
2245xfs_ifree_cluster(
2246	xfs_inode_t	*free_ip,
2247	xfs_trans_t	*tp,
2248	xfs_ino_t	inum)
2249{
2250	xfs_mount_t		*mp = free_ip->i_mount;
2251	int			blks_per_cluster;
2252	int			inodes_per_cluster;
2253	int			nbufs;
2254	int			i, j;
 
2255	xfs_daddr_t		blkno;
2256	xfs_buf_t		*bp;
2257	xfs_inode_t		*ip;
2258	xfs_inode_log_item_t	*iip;
2259	xfs_log_item_t		*lip;
2260	struct xfs_perag	*pag;
 
2261
 
2262	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2263	blks_per_cluster = xfs_icluster_size_fsb(mp);
2264	inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
2265	nbufs = mp->m_ialloc_blks / blks_per_cluster;
2266
2267	for (j = 0; j < nbufs; j++, inum += inodes_per_cluster) {
 
 
 
 
 
 
 
 
 
 
 
2268		blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2269					 XFS_INO_TO_AGBNO(mp, inum));
2270
2271		/*
2272		 * We obtain and lock the backing buffer first in the process
2273		 * here, as we have to ensure that any dirty inode that we
2274		 * can't get the flush lock on is attached to the buffer.
2275		 * If we scan the in-memory inodes first, then buffer IO can
2276		 * complete before we get a lock on it, and hence we may fail
2277		 * to mark all the active inodes on the buffer stale.
2278		 */
2279		bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2280					mp->m_bsize * blks_per_cluster,
2281					XBF_UNMAPPED);
2282
2283		if (!bp)
2284			return ENOMEM;
2285
2286		/*
2287		 * This buffer may not have been correctly initialised as we
2288		 * didn't read it from disk. That's not important because we are
2289		 * only using to mark the buffer as stale in the log, and to
2290		 * attach stale cached inodes on it. That means it will never be
2291		 * dispatched for IO. If it is, we want to know about it, and we
2292		 * want it to fail. We can acheive this by adding a write
2293		 * verifier to the buffer.
2294		 */
2295		 bp->b_ops = &xfs_inode_buf_ops;
2296
2297		/*
2298		 * Walk the inodes already attached to the buffer and mark them
2299		 * stale. These will all have the flush locks held, so an
2300		 * in-memory inode walk can't lock them. By marking them all
2301		 * stale first, we will not attempt to lock them in the loop
2302		 * below as the XFS_ISTALE flag will be set.
2303		 */
2304		lip = bp->b_fspriv;
2305		while (lip) {
2306			if (lip->li_type == XFS_LI_INODE) {
2307				iip = (xfs_inode_log_item_t *)lip;
2308				ASSERT(iip->ili_logged == 1);
2309				lip->li_cb = xfs_istale_done;
2310				xfs_trans_ail_copy_lsn(mp->m_ail,
2311							&iip->ili_flush_lsn,
2312							&iip->ili_item.li_lsn);
2313				xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2314			}
2315			lip = lip->li_bio_list;
2316		}
2317
2318
2319		/*
2320		 * For each inode in memory attempt to add it to the inode
2321		 * buffer and set it up for being staled on buffer IO
2322		 * completion.  This is safe as we've locked out tail pushing
2323		 * and flushing by locking the buffer.
2324		 *
2325		 * We have already marked every inode that was part of a
2326		 * transaction stale above, which means there is no point in
2327		 * even trying to lock them.
2328		 */
2329		for (i = 0; i < inodes_per_cluster; i++) {
2330retry:
2331			rcu_read_lock();
2332			ip = radix_tree_lookup(&pag->pag_ici_root,
2333					XFS_INO_TO_AGINO(mp, (inum + i)));
2334
2335			/* Inode not in memory, nothing to do */
2336			if (!ip) {
2337				rcu_read_unlock();
2338				continue;
2339			}
2340
2341			/*
2342			 * because this is an RCU protected lookup, we could
2343			 * find a recently freed or even reallocated inode
2344			 * during the lookup. We need to check under the
2345			 * i_flags_lock for a valid inode here. Skip it if it
2346			 * is not valid, the wrong inode or stale.
2347			 */
2348			spin_lock(&ip->i_flags_lock);
2349			if (ip->i_ino != inum + i ||
2350			    __xfs_iflags_test(ip, XFS_ISTALE)) {
2351				spin_unlock(&ip->i_flags_lock);
2352				rcu_read_unlock();
2353				continue;
2354			}
2355			spin_unlock(&ip->i_flags_lock);
2356
2357			/*
2358			 * Don't try to lock/unlock the current inode, but we
2359			 * _cannot_ skip the other inodes that we did not find
2360			 * in the list attached to the buffer and are not
2361			 * already marked stale. If we can't lock it, back off
2362			 * and retry.
2363			 */
2364			if (ip != free_ip &&
2365			    !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2366				rcu_read_unlock();
2367				delay(1);
2368				goto retry;
2369			}
2370			rcu_read_unlock();
2371
2372			xfs_iflock(ip);
2373			xfs_iflags_set(ip, XFS_ISTALE);
2374
2375			/*
2376			 * we don't need to attach clean inodes or those only
2377			 * with unlogged changes (which we throw away, anyway).
2378			 */
2379			iip = ip->i_itemp;
2380			if (!iip || xfs_inode_clean(ip)) {
2381				ASSERT(ip != free_ip);
2382				xfs_ifunlock(ip);
2383				xfs_iunlock(ip, XFS_ILOCK_EXCL);
2384				continue;
2385			}
2386
2387			iip->ili_last_fields = iip->ili_fields;
2388			iip->ili_fields = 0;
 
2389			iip->ili_logged = 1;
2390			xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2391						&iip->ili_item.li_lsn);
2392
2393			xfs_buf_attach_iodone(bp, xfs_istale_done,
2394						  &iip->ili_item);
2395
2396			if (ip != free_ip)
2397				xfs_iunlock(ip, XFS_ILOCK_EXCL);
2398		}
2399
2400		xfs_trans_stale_inode_buf(tp, bp);
2401		xfs_trans_binval(tp, bp);
2402	}
2403
2404	xfs_perag_put(pag);
2405	return 0;
2406}
2407
2408/*
2409 * This is called to return an inode to the inode free list.
2410 * The inode should already be truncated to 0 length and have
2411 * no pages associated with it.  This routine also assumes that
2412 * the inode is already a part of the transaction.
2413 *
2414 * The on-disk copy of the inode will have been added to the list
2415 * of unlinked inodes in the AGI. We need to remove the inode from
2416 * that list atomically with respect to freeing it here.
2417 */
2418int
2419xfs_ifree(
2420	xfs_trans_t	*tp,
2421	xfs_inode_t	*ip,
2422	xfs_bmap_free_t	*flist)
2423{
2424	int			error;
2425	int			delete;
2426	xfs_ino_t		first_ino;
2427
2428	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2429	ASSERT(ip->i_d.di_nlink == 0);
2430	ASSERT(ip->i_d.di_nextents == 0);
2431	ASSERT(ip->i_d.di_anextents == 0);
2432	ASSERT(ip->i_d.di_size == 0 || !S_ISREG(ip->i_d.di_mode));
2433	ASSERT(ip->i_d.di_nblocks == 0);
2434
2435	/*
2436	 * Pull the on-disk inode from the AGI unlinked list.
2437	 */
2438	error = xfs_iunlink_remove(tp, ip);
2439	if (error)
2440		return error;
2441
2442	error = xfs_difree(tp, ip->i_ino, flist, &delete, &first_ino);
2443	if (error)
2444		return error;
2445
2446	ip->i_d.di_mode = 0;		/* mark incore inode as free */
2447	ip->i_d.di_flags = 0;
2448	ip->i_d.di_dmevmask = 0;
2449	ip->i_d.di_forkoff = 0;		/* mark the attr fork not in use */
2450	ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2451	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2452	/*
2453	 * Bump the generation count so no one will be confused
2454	 * by reincarnations of this inode.
2455	 */
2456	ip->i_d.di_gen++;
2457	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2458
2459	if (delete)
2460		error = xfs_ifree_cluster(ip, tp, first_ino);
2461
2462	return error;
2463}
2464
2465/*
2466 * This is called to unpin an inode.  The caller must have the inode locked
2467 * in at least shared mode so that the buffer cannot be subsequently pinned
2468 * once someone is waiting for it to be unpinned.
2469 */
2470static void
2471xfs_iunpin(
2472	struct xfs_inode	*ip)
2473{
2474	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2475
2476	trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2477
2478	/* Give the log a push to start the unpinning I/O */
2479	xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0);
2480
2481}
2482
2483static void
2484__xfs_iunpin_wait(
2485	struct xfs_inode	*ip)
2486{
2487	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2488	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2489
2490	xfs_iunpin(ip);
2491
2492	do {
2493		prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
2494		if (xfs_ipincount(ip))
2495			io_schedule();
2496	} while (xfs_ipincount(ip));
2497	finish_wait(wq, &wait.wait);
2498}
2499
2500void
2501xfs_iunpin_wait(
2502	struct xfs_inode	*ip)
2503{
2504	if (xfs_ipincount(ip))
2505		__xfs_iunpin_wait(ip);
2506}
2507
2508/*
2509 * Removing an inode from the namespace involves removing the directory entry
2510 * and dropping the link count on the inode. Removing the directory entry can
2511 * result in locking an AGF (directory blocks were freed) and removing a link
2512 * count can result in placing the inode on an unlinked list which results in
2513 * locking an AGI.
2514 *
2515 * The big problem here is that we have an ordering constraint on AGF and AGI
2516 * locking - inode allocation locks the AGI, then can allocate a new extent for
2517 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2518 * removes the inode from the unlinked list, requiring that we lock the AGI
2519 * first, and then freeing the inode can result in an inode chunk being freed
2520 * and hence freeing disk space requiring that we lock an AGF.
2521 *
2522 * Hence the ordering that is imposed by other parts of the code is AGI before
2523 * AGF. This means we cannot remove the directory entry before we drop the inode
2524 * reference count and put it on the unlinked list as this results in a lock
2525 * order of AGF then AGI, and this can deadlock against inode allocation and
2526 * freeing. Therefore we must drop the link counts before we remove the
2527 * directory entry.
2528 *
2529 * This is still safe from a transactional point of view - it is not until we
2530 * get to xfs_bmap_finish() that we have the possibility of multiple
2531 * transactions in this operation. Hence as long as we remove the directory
2532 * entry and drop the link count in the first transaction of the remove
2533 * operation, there are no transactional constraints on the ordering here.
2534 */
2535int
2536xfs_remove(
2537	xfs_inode_t             *dp,
2538	struct xfs_name		*name,
2539	xfs_inode_t		*ip)
2540{
2541	xfs_mount_t		*mp = dp->i_mount;
2542	xfs_trans_t             *tp = NULL;
2543	int			is_dir = S_ISDIR(ip->i_d.di_mode);
2544	int                     error = 0;
2545	xfs_bmap_free_t         free_list;
2546	xfs_fsblock_t           first_block;
2547	int			cancel_flags;
2548	int			committed;
2549	int			link_zero;
2550	uint			resblks;
2551	uint			log_count;
2552
2553	trace_xfs_remove(dp, name);
2554
2555	if (XFS_FORCED_SHUTDOWN(mp))
2556		return XFS_ERROR(EIO);
2557
2558	error = xfs_qm_dqattach(dp, 0);
2559	if (error)
2560		goto std_return;
2561
2562	error = xfs_qm_dqattach(ip, 0);
2563	if (error)
2564		goto std_return;
2565
2566	if (is_dir) {
2567		tp = xfs_trans_alloc(mp, XFS_TRANS_RMDIR);
2568		log_count = XFS_DEFAULT_LOG_COUNT;
2569	} else {
2570		tp = xfs_trans_alloc(mp, XFS_TRANS_REMOVE);
2571		log_count = XFS_REMOVE_LOG_COUNT;
2572	}
2573	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
2574
2575	/*
2576	 * We try to get the real space reservation first,
2577	 * allowing for directory btree deletion(s) implying
2578	 * possible bmap insert(s).  If we can't get the space
2579	 * reservation then we use 0 instead, and avoid the bmap
2580	 * btree insert(s) in the directory code by, if the bmap
2581	 * insert tries to happen, instead trimming the LAST
2582	 * block from the directory.
2583	 */
2584	resblks = XFS_REMOVE_SPACE_RES(mp);
2585	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, resblks, 0);
2586	if (error == ENOSPC) {
2587		resblks = 0;
2588		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, 0, 0);
 
2589	}
2590	if (error) {
2591		ASSERT(error != ENOSPC);
2592		cancel_flags = 0;
2593		goto out_trans_cancel;
2594	}
2595
2596	xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
2597
2598	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2599	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2600
2601	/*
2602	 * If we're removing a directory perform some additional validation.
2603	 */
2604	cancel_flags |= XFS_TRANS_ABORT;
2605	if (is_dir) {
2606		ASSERT(ip->i_d.di_nlink >= 2);
2607		if (ip->i_d.di_nlink != 2) {
2608			error = XFS_ERROR(ENOTEMPTY);
2609			goto out_trans_cancel;
2610		}
2611		if (!xfs_dir_isempty(ip)) {
2612			error = XFS_ERROR(ENOTEMPTY);
2613			goto out_trans_cancel;
2614		}
2615
2616		/* Drop the link from ip's "..".  */
2617		error = xfs_droplink(tp, dp);
2618		if (error)
2619			goto out_trans_cancel;
2620
2621		/* Drop the "." link from ip to self.  */
2622		error = xfs_droplink(tp, ip);
2623		if (error)
2624			goto out_trans_cancel;
2625	} else {
2626		/*
2627		 * When removing a non-directory we need to log the parent
2628		 * inode here.  For a directory this is done implicitly
2629		 * by the xfs_droplink call for the ".." entry.
2630		 */
2631		xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2632	}
2633	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2634
2635	/* Drop the link from dp to ip. */
2636	error = xfs_droplink(tp, ip);
2637	if (error)
2638		goto out_trans_cancel;
2639
2640	/* Determine if this is the last link while the inode is locked */
2641	link_zero = (ip->i_d.di_nlink == 0);
2642
2643	xfs_bmap_init(&free_list, &first_block);
2644	error = xfs_dir_removename(tp, dp, name, ip->i_ino,
2645					&first_block, &free_list, resblks);
2646	if (error) {
2647		ASSERT(error != ENOENT);
2648		goto out_bmap_cancel;
2649	}
2650
2651	/*
2652	 * If this is a synchronous mount, make sure that the
2653	 * remove transaction goes to disk before returning to
2654	 * the user.
2655	 */
2656	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2657		xfs_trans_set_sync(tp);
2658
2659	error = xfs_bmap_finish(&tp, &free_list, &committed);
2660	if (error)
2661		goto out_bmap_cancel;
2662
2663	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2664	if (error)
2665		goto std_return;
2666
2667	/*
2668	 * If we are using filestreams, kill the stream association.
2669	 * If the file is still open it may get a new one but that
2670	 * will get killed on last close in xfs_close() so we don't
2671	 * have to worry about that.
2672	 */
2673	if (!is_dir && link_zero && xfs_inode_is_filestream(ip))
2674		xfs_filestream_deassociate(ip);
2675
2676	return 0;
2677
2678 out_bmap_cancel:
2679	xfs_bmap_cancel(&free_list);
2680 out_trans_cancel:
2681	xfs_trans_cancel(tp, cancel_flags);
2682 std_return:
2683	return error;
2684}
2685
2686/*
2687 * Enter all inodes for a rename transaction into a sorted array.
2688 */
 
2689STATIC void
2690xfs_sort_for_rename(
2691	xfs_inode_t	*dp1,	/* in: old (source) directory inode */
2692	xfs_inode_t	*dp2,	/* in: new (target) directory inode */
2693	xfs_inode_t	*ip1,	/* in: inode of old entry */
2694	xfs_inode_t	*ip2,	/* in: inode of new entry, if it
2695				   already exists, NULL otherwise. */
2696	xfs_inode_t	**i_tab,/* out: array of inode returned, sorted */
2697	int		*num_inodes)  /* out: number of inodes in array */
2698{
2699	xfs_inode_t		*temp;
2700	int			i, j;
2701
 
 
 
2702	/*
2703	 * i_tab contains a list of pointers to inodes.  We initialize
2704	 * the table here & we'll sort it.  We will then use it to
2705	 * order the acquisition of the inode locks.
2706	 *
2707	 * Note that the table may contain duplicates.  e.g., dp1 == dp2.
2708	 */
2709	i_tab[0] = dp1;
2710	i_tab[1] = dp2;
2711	i_tab[2] = ip1;
2712	if (ip2) {
2713		*num_inodes = 4;
2714		i_tab[3] = ip2;
2715	} else {
2716		*num_inodes = 3;
2717		i_tab[3] = NULL;
2718	}
2719
2720	/*
2721	 * Sort the elements via bubble sort.  (Remember, there are at
2722	 * most 4 elements to sort, so this is adequate.)
2723	 */
2724	for (i = 0; i < *num_inodes; i++) {
2725		for (j = 1; j < *num_inodes; j++) {
2726			if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2727				temp = i_tab[j];
2728				i_tab[j] = i_tab[j-1];
2729				i_tab[j-1] = temp;
2730			}
2731		}
2732	}
2733}
2734
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2735/*
2736 * xfs_rename
2737 */
2738int
2739xfs_rename(
2740	xfs_inode_t	*src_dp,
2741	struct xfs_name	*src_name,
2742	xfs_inode_t	*src_ip,
2743	xfs_inode_t	*target_dp,
2744	struct xfs_name	*target_name,
2745	xfs_inode_t	*target_ip)
2746{
2747	xfs_trans_t	*tp = NULL;
2748	xfs_mount_t	*mp = src_dp->i_mount;
2749	int		new_parent;		/* moving to a new dir */
2750	int		src_is_directory;	/* src_name is a directory */
2751	int		error;
2752	xfs_bmap_free_t free_list;
2753	xfs_fsblock_t   first_block;
2754	int		cancel_flags;
2755	int		committed;
2756	xfs_inode_t	*inodes[4];
2757	int		spaceres;
2758	int		num_inodes;
2759
2760	trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2761
2762	new_parent = (src_dp != target_dp);
2763	src_is_directory = S_ISDIR(src_ip->i_d.di_mode);
2764
2765	xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2766				inodes, &num_inodes);
2767
2768	xfs_bmap_init(&free_list, &first_block);
2769	tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME);
2770	cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
2771	spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2772	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, spaceres, 0);
2773	if (error == ENOSPC) {
2774		spaceres = 0;
2775		error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, 0, 0);
2776	}
2777	if (error) {
2778		xfs_trans_cancel(tp, 0);
2779		goto std_return;
2780	}
 
 
2781
2782	/*
2783	 * Attach the dquots to the inodes
2784	 */
2785	error = xfs_qm_vop_rename_dqattach(inodes);
2786	if (error) {
2787		xfs_trans_cancel(tp, cancel_flags);
2788		goto std_return;
2789	}
2790
2791	/*
2792	 * Lock all the participating inodes. Depending upon whether
2793	 * the target_name exists in the target directory, and
2794	 * whether the target directory is the same as the source
2795	 * directory, we can lock from 2 to 4 inodes.
2796	 */
2797	xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2798
2799	/*
2800	 * Join all the inodes to the transaction. From this point on,
2801	 * we can rely on either trans_commit or trans_cancel to unlock
2802	 * them.
2803	 */
2804	xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2805	if (new_parent)
2806		xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2807	xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
2808	if (target_ip)
2809		xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
 
 
2810
2811	/*
2812	 * If we are using project inheritance, we only allow renames
2813	 * into our tree when the project IDs are the same; else the
2814	 * tree quota mechanism would be circumvented.
2815	 */
2816	if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
2817		     (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
2818		error = XFS_ERROR(EXDEV);
2819		goto error_return;
2820	}
2821
 
 
 
 
 
 
 
 
2822	/*
2823	 * Set up the target.
2824	 */
2825	if (target_ip == NULL) {
2826		/*
2827		 * If there's no space reservation, check the entry will
2828		 * fit before actually inserting it.
2829		 */
2830		error = xfs_dir_canenter(tp, target_dp, target_name, spaceres);
2831		if (error)
2832			goto error_return;
 
 
2833		/*
2834		 * If target does not exist and the rename crosses
2835		 * directories, adjust the target directory link count
2836		 * to account for the ".." reference from the new entry.
2837		 */
2838		error = xfs_dir_createname(tp, target_dp, target_name,
2839						src_ip->i_ino, &first_block,
2840						&free_list, spaceres);
2841		if (error == ENOSPC)
2842			goto error_return;
2843		if (error)
2844			goto abort_return;
2845
2846		xfs_trans_ichgtime(tp, target_dp,
2847					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2848
2849		if (new_parent && src_is_directory) {
2850			error = xfs_bumplink(tp, target_dp);
2851			if (error)
2852				goto abort_return;
2853		}
2854	} else { /* target_ip != NULL */
2855		/*
2856		 * If target exists and it's a directory, check that both
2857		 * target and source are directories and that target can be
2858		 * destroyed, or that neither is a directory.
2859		 */
2860		if (S_ISDIR(target_ip->i_d.di_mode)) {
2861			/*
2862			 * Make sure target dir is empty.
2863			 */
2864			if (!(xfs_dir_isempty(target_ip)) ||
2865			    (target_ip->i_d.di_nlink > 2)) {
2866				error = XFS_ERROR(EEXIST);
2867				goto error_return;
2868			}
2869		}
2870
2871		/*
2872		 * Link the source inode under the target name.
2873		 * If the source inode is a directory and we are moving
2874		 * it across directories, its ".." entry will be
2875		 * inconsistent until we replace that down below.
2876		 *
2877		 * In case there is already an entry with the same
2878		 * name at the destination directory, remove it first.
2879		 */
2880		error = xfs_dir_replace(tp, target_dp, target_name,
2881					src_ip->i_ino,
2882					&first_block, &free_list, spaceres);
2883		if (error)
2884			goto abort_return;
2885
2886		xfs_trans_ichgtime(tp, target_dp,
2887					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2888
2889		/*
2890		 * Decrement the link count on the target since the target
2891		 * dir no longer points to it.
2892		 */
2893		error = xfs_droplink(tp, target_ip);
2894		if (error)
2895			goto abort_return;
2896
2897		if (src_is_directory) {
2898			/*
2899			 * Drop the link from the old "." entry.
2900			 */
2901			error = xfs_droplink(tp, target_ip);
2902			if (error)
2903				goto abort_return;
2904		}
2905	} /* target_ip != NULL */
2906
2907	/*
2908	 * Remove the source.
2909	 */
2910	if (new_parent && src_is_directory) {
2911		/*
2912		 * Rewrite the ".." entry to point to the new
2913		 * directory.
2914		 */
2915		error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
2916					target_dp->i_ino,
2917					&first_block, &free_list, spaceres);
2918		ASSERT(error != EEXIST);
2919		if (error)
2920			goto abort_return;
2921	}
2922
2923	/*
2924	 * We always want to hit the ctime on the source inode.
2925	 *
2926	 * This isn't strictly required by the standards since the source
2927	 * inode isn't really being changed, but old unix file systems did
2928	 * it and some incremental backup programs won't work without it.
2929	 */
2930	xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
2931	xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
2932
2933	/*
2934	 * Adjust the link count on src_dp.  This is necessary when
2935	 * renaming a directory, either within one parent when
2936	 * the target existed, or across two parent directories.
2937	 */
2938	if (src_is_directory && (new_parent || target_ip != NULL)) {
2939
2940		/*
2941		 * Decrement link count on src_directory since the
2942		 * entry that's moved no longer points to it.
2943		 */
2944		error = xfs_droplink(tp, src_dp);
2945		if (error)
2946			goto abort_return;
2947	}
2948
2949	error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
2950					&first_block, &free_list, spaceres);
 
 
 
 
 
 
 
 
 
2951	if (error)
2952		goto abort_return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2953
2954	xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2955	xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
2956	if (new_parent)
2957		xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
2958
2959	/*
2960	 * If this is a synchronous mount, make sure that the
2961	 * rename transaction goes to disk before returning to
2962	 * the user.
2963	 */
2964	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
2965		xfs_trans_set_sync(tp);
2966	}
2967
2968	error = xfs_bmap_finish(&tp, &free_list, &committed);
2969	if (error) {
2970		xfs_bmap_cancel(&free_list);
2971		xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
2972				 XFS_TRANS_ABORT));
2973		goto std_return;
2974	}
2975
2976	/*
2977	 * trans_commit will unlock src_ip, target_ip & decrement
2978	 * the vnode references.
2979	 */
2980	return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2981
2982 abort_return:
2983	cancel_flags |= XFS_TRANS_ABORT;
2984 error_return:
2985	xfs_bmap_cancel(&free_list);
2986	xfs_trans_cancel(tp, cancel_flags);
2987 std_return:
 
2988	return error;
2989}
2990
2991STATIC int
2992xfs_iflush_cluster(
2993	xfs_inode_t	*ip,
2994	xfs_buf_t	*bp)
2995{
2996	xfs_mount_t		*mp = ip->i_mount;
2997	struct xfs_perag	*pag;
2998	unsigned long		first_index, mask;
2999	unsigned long		inodes_per_cluster;
3000	int			ilist_size;
3001	xfs_inode_t		**ilist;
3002	xfs_inode_t		*iq;
3003	int			nr_found;
3004	int			clcount = 0;
3005	int			bufwasdelwri;
3006	int			i;
3007
3008	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
3009
3010	inodes_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
3011	ilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
3012	ilist = kmem_alloc(ilist_size, KM_MAYFAIL|KM_NOFS);
3013	if (!ilist)
3014		goto out_put;
3015
3016	mask = ~(((mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog)) - 1);
3017	first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
3018	rcu_read_lock();
3019	/* really need a gang lookup range call here */
3020	nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)ilist,
3021					first_index, inodes_per_cluster);
3022	if (nr_found == 0)
3023		goto out_free;
3024
3025	for (i = 0; i < nr_found; i++) {
3026		iq = ilist[i];
3027		if (iq == ip)
3028			continue;
3029
3030		/*
3031		 * because this is an RCU protected lookup, we could find a
3032		 * recently freed or even reallocated inode during the lookup.
3033		 * We need to check under the i_flags_lock for a valid inode
3034		 * here. Skip it if it is not valid or the wrong inode.
3035		 */
3036		spin_lock(&ip->i_flags_lock);
3037		if (!ip->i_ino ||
3038		    (XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) != first_index) {
3039			spin_unlock(&ip->i_flags_lock);
3040			continue;
3041		}
3042		spin_unlock(&ip->i_flags_lock);
 
 
 
 
 
 
 
 
 
 
3043
3044		/*
3045		 * Do an un-protected check to see if the inode is dirty and
3046		 * is a candidate for flushing.  These checks will be repeated
3047		 * later after the appropriate locks are acquired.
3048		 */
3049		if (xfs_inode_clean(iq) && xfs_ipincount(iq) == 0)
3050			continue;
3051
3052		/*
3053		 * Try to get locks.  If any are unavailable or it is pinned,
3054		 * then this inode cannot be flushed and is skipped.
3055		 */
3056
3057		if (!xfs_ilock_nowait(iq, XFS_ILOCK_SHARED))
 
 
 
3058			continue;
3059		if (!xfs_iflock_nowait(iq)) {
3060			xfs_iunlock(iq, XFS_ILOCK_SHARED);
 
 
3061			continue;
3062		}
3063		if (xfs_ipincount(iq)) {
3064			xfs_ifunlock(iq);
3065			xfs_iunlock(iq, XFS_ILOCK_SHARED);
 
 
 
 
 
 
 
 
3066			continue;
3067		}
3068
3069		/*
3070		 * arriving here means that this inode can be flushed.  First
3071		 * re-check that it's dirty before flushing.
3072		 */
3073		if (!xfs_inode_clean(iq)) {
3074			int	error;
3075			error = xfs_iflush_int(iq, bp);
3076			if (error) {
3077				xfs_iunlock(iq, XFS_ILOCK_SHARED);
3078				goto cluster_corrupt_out;
3079			}
3080			clcount++;
3081		} else {
3082			xfs_ifunlock(iq);
3083		}
3084		xfs_iunlock(iq, XFS_ILOCK_SHARED);
3085	}
3086
3087	if (clcount) {
3088		XFS_STATS_INC(xs_icluster_flushcnt);
3089		XFS_STATS_ADD(xs_icluster_flushinode, clcount);
3090	}
3091
3092out_free:
3093	rcu_read_unlock();
3094	kmem_free(ilist);
3095out_put:
3096	xfs_perag_put(pag);
3097	return 0;
3098
3099
3100cluster_corrupt_out:
3101	/*
3102	 * Corruption detected in the clustering loop.  Invalidate the
3103	 * inode buffer and shut down the filesystem.
3104	 */
3105	rcu_read_unlock();
3106	/*
3107	 * Clean up the buffer.  If it was delwri, just release it --
3108	 * brelse can handle it with no problems.  If not, shut down the
3109	 * filesystem before releasing the buffer.
3110	 */
3111	bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
3112	if (bufwasdelwri)
3113		xfs_buf_relse(bp);
3114
3115	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3116
3117	if (!bufwasdelwri) {
3118		/*
3119		 * Just like incore_relse: if we have b_iodone functions,
3120		 * mark the buffer as an error and call them.  Otherwise
3121		 * mark it as stale and brelse.
3122		 */
3123		if (bp->b_iodone) {
3124			XFS_BUF_UNDONE(bp);
3125			xfs_buf_stale(bp);
3126			xfs_buf_ioerror(bp, EIO);
3127			xfs_buf_ioend(bp, 0);
3128		} else {
3129			xfs_buf_stale(bp);
3130			xfs_buf_relse(bp);
3131		}
3132	}
3133
3134	/*
3135	 * Unlocks the flush lock
3136	 */
3137	xfs_iflush_abort(iq, false);
3138	kmem_free(ilist);
3139	xfs_perag_put(pag);
3140	return XFS_ERROR(EFSCORRUPTED);
3141}
3142
3143/*
3144 * Flush dirty inode metadata into the backing buffer.
3145 *
3146 * The caller must have the inode lock and the inode flush lock held.  The
3147 * inode lock will still be held upon return to the caller, and the inode
3148 * flush lock will be released after the inode has reached the disk.
3149 *
3150 * The caller must write out the buffer returned in *bpp and release it.
3151 */
3152int
3153xfs_iflush(
3154	struct xfs_inode	*ip,
3155	struct xfs_buf		**bpp)
3156{
3157	struct xfs_mount	*mp = ip->i_mount;
3158	struct xfs_buf		*bp;
3159	struct xfs_dinode	*dip;
3160	int			error;
3161
3162	XFS_STATS_INC(xs_iflush_count);
3163
3164	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3165	ASSERT(xfs_isiflocked(ip));
3166	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3167	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3168
3169	*bpp = NULL;
3170
3171	xfs_iunpin_wait(ip);
3172
3173	/*
3174	 * For stale inodes we cannot rely on the backing buffer remaining
3175	 * stale in cache for the remaining life of the stale inode and so
3176	 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3177	 * inodes below. We have to check this after ensuring the inode is
3178	 * unpinned so that it is safe to reclaim the stale inode after the
3179	 * flush call.
3180	 */
3181	if (xfs_iflags_test(ip, XFS_ISTALE)) {
3182		xfs_ifunlock(ip);
3183		return 0;
3184	}
3185
3186	/*
3187	 * This may have been unpinned because the filesystem is shutting
3188	 * down forcibly. If that's the case we must not write this inode
3189	 * to disk, because the log record didn't make it to disk.
3190	 *
3191	 * We also have to remove the log item from the AIL in this case,
3192	 * as we wait for an empty AIL as part of the unmount process.
3193	 */
3194	if (XFS_FORCED_SHUTDOWN(mp)) {
3195		error = XFS_ERROR(EIO);
3196		goto abort_out;
3197	}
3198
3199	/*
3200	 * Get the buffer containing the on-disk inode.
 
 
 
 
 
 
3201	 */
3202	error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3203			       0);
3204	if (error || !bp) {
3205		xfs_ifunlock(ip);
3206		return error;
3207	}
 
 
3208
3209	/*
3210	 * First flush out the inode that xfs_iflush was called with.
3211	 */
3212	error = xfs_iflush_int(ip, bp);
3213	if (error)
3214		goto corrupt_out;
3215
3216	/*
3217	 * If the buffer is pinned then push on the log now so we won't
3218	 * get stuck waiting in the write for too long.
3219	 */
3220	if (xfs_buf_ispinned(bp))
3221		xfs_log_force(mp, 0);
3222
3223	/*
3224	 * inode clustering:
3225	 * see if other inodes can be gathered into this write
3226	 */
3227	error = xfs_iflush_cluster(ip, bp);
3228	if (error)
3229		goto cluster_corrupt_out;
3230
3231	*bpp = bp;
3232	return 0;
3233
3234corrupt_out:
3235	xfs_buf_relse(bp);
 
3236	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3237cluster_corrupt_out:
3238	error = XFS_ERROR(EFSCORRUPTED);
3239abort_out:
3240	/*
3241	 * Unlocks the flush lock
3242	 */
3243	xfs_iflush_abort(ip, false);
3244	return error;
3245}
3246
3247STATIC int
3248xfs_iflush_int(
3249	struct xfs_inode	*ip,
3250	struct xfs_buf		*bp)
3251{
3252	struct xfs_inode_log_item *iip = ip->i_itemp;
3253	struct xfs_dinode	*dip;
3254	struct xfs_mount	*mp = ip->i_mount;
3255
3256	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3257	ASSERT(xfs_isiflocked(ip));
3258	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3259	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3260	ASSERT(iip != NULL && iip->ili_fields != 0);
 
3261
3262	/* set *dip = inode's place in the buffer */
3263	dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
3264
3265	if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3266			       mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
3267		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3268			"%s: Bad inode %Lu magic number 0x%x, ptr 0x%p",
3269			__func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3270		goto corrupt_out;
3271	}
3272	if (XFS_TEST_ERROR(ip->i_d.di_magic != XFS_DINODE_MAGIC,
3273				mp, XFS_ERRTAG_IFLUSH_2, XFS_RANDOM_IFLUSH_2)) {
3274		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3275			"%s: Bad inode %Lu, ptr 0x%p, magic number 0x%x",
3276			__func__, ip->i_ino, ip, ip->i_d.di_magic);
3277		goto corrupt_out;
3278	}
3279	if (S_ISREG(ip->i_d.di_mode)) {
3280		if (XFS_TEST_ERROR(
3281		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3282		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3283		    mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
3284			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3285				"%s: Bad regular inode %Lu, ptr 0x%p",
3286				__func__, ip->i_ino, ip);
3287			goto corrupt_out;
3288		}
3289	} else if (S_ISDIR(ip->i_d.di_mode)) {
3290		if (XFS_TEST_ERROR(
3291		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3292		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3293		    (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3294		    mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
3295			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3296				"%s: Bad directory inode %Lu, ptr 0x%p",
3297				__func__, ip->i_ino, ip);
3298			goto corrupt_out;
3299		}
3300	}
3301	if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3302				ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
3303				XFS_RANDOM_IFLUSH_5)) {
3304		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3305			"%s: detected corrupt incore inode %Lu, "
3306			"total extents = %d, nblocks = %Ld, ptr 0x%p",
3307			__func__, ip->i_ino,
3308			ip->i_d.di_nextents + ip->i_d.di_anextents,
3309			ip->i_d.di_nblocks, ip);
3310		goto corrupt_out;
3311	}
3312	if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3313				mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
3314		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3315			"%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
3316			__func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3317		goto corrupt_out;
3318	}
3319
3320	/*
3321	 * Inode item log recovery for v1/v2 inodes are dependent on the
3322	 * di_flushiter count for correct sequencing. We bump the flush
3323	 * iteration count so we can detect flushes which postdate a log record
3324	 * during recovery. This is redundant as we now log every change and
3325	 * hence this can't happen but we need to still do it to ensure
3326	 * backwards compatibility with old kernels that predate logging all
3327	 * inode changes.
3328	 */
3329	if (ip->i_d.di_version < 3)
3330		ip->i_d.di_flushiter++;
3331
3332	/*
3333	 * Copy the dirty parts of the inode into the on-disk
3334	 * inode.  We always copy out the core of the inode,
3335	 * because if the inode is dirty at all the core must
3336	 * be.
3337	 */
3338	xfs_dinode_to_disk(dip, &ip->i_d);
3339
3340	/* Wrap, we never let the log put out DI_MAX_FLUSH */
3341	if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3342		ip->i_d.di_flushiter = 0;
3343
3344	/*
3345	 * If this is really an old format inode and the superblock version
3346	 * has not been updated to support only new format inodes, then
3347	 * convert back to the old inode format.  If the superblock version
3348	 * has been updated, then make the conversion permanent.
3349	 */
3350	ASSERT(ip->i_d.di_version == 1 || xfs_sb_version_hasnlink(&mp->m_sb));
3351	if (ip->i_d.di_version == 1) {
3352		if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
3353			/*
3354			 * Convert it back.
3355			 */
3356			ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
3357			dip->di_onlink = cpu_to_be16(ip->i_d.di_nlink);
3358		} else {
3359			/*
3360			 * The superblock version has already been bumped,
3361			 * so just make the conversion to the new inode
3362			 * format permanent.
3363			 */
3364			ip->i_d.di_version = 2;
3365			dip->di_version = 2;
3366			ip->i_d.di_onlink = 0;
3367			dip->di_onlink = 0;
3368			memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
3369			memset(&(dip->di_pad[0]), 0,
3370			      sizeof(dip->di_pad));
3371			ASSERT(xfs_get_projid(ip) == 0);
3372		}
3373	}
3374
3375	xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK, bp);
3376	if (XFS_IFORK_Q(ip))
3377		xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK, bp);
3378	xfs_inobp_check(mp, bp);
3379
3380	/*
3381	 * We've recorded everything logged in the inode, so we'd like to clear
3382	 * the ili_fields bits so we don't log and flush things unnecessarily.
3383	 * However, we can't stop logging all this information until the data
3384	 * we've copied into the disk buffer is written to disk.  If we did we
3385	 * might overwrite the copy of the inode in the log with all the data
3386	 * after re-logging only part of it, and in the face of a crash we
3387	 * wouldn't have all the data we need to recover.
3388	 *
3389	 * What we do is move the bits to the ili_last_fields field.  When
3390	 * logging the inode, these bits are moved back to the ili_fields field.
3391	 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3392	 * know that the information those bits represent is permanently on
3393	 * disk.  As long as the flush completes before the inode is logged
3394	 * again, then both ili_fields and ili_last_fields will be cleared.
3395	 *
3396	 * We can play with the ili_fields bits here, because the inode lock
3397	 * must be held exclusively in order to set bits there and the flush
3398	 * lock protects the ili_last_fields bits.  Set ili_logged so the flush
3399	 * done routine can tell whether or not to look in the AIL.  Also, store
3400	 * the current LSN of the inode so that we can tell whether the item has
3401	 * moved in the AIL from xfs_iflush_done().  In order to read the lsn we
3402	 * need the AIL lock, because it is a 64 bit value that cannot be read
3403	 * atomically.
3404	 */
3405	iip->ili_last_fields = iip->ili_fields;
3406	iip->ili_fields = 0;
 
3407	iip->ili_logged = 1;
3408
3409	xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3410				&iip->ili_item.li_lsn);
3411
3412	/*
3413	 * Attach the function xfs_iflush_done to the inode's
3414	 * buffer.  This will remove the inode from the AIL
3415	 * and unlock the inode's flush lock when the inode is
3416	 * completely written to disk.
3417	 */
3418	xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3419
3420	/* update the lsn in the on disk inode if required */
3421	if (ip->i_d.di_version == 3)
3422		dip->di_lsn = cpu_to_be64(iip->ili_item.li_lsn);
3423
3424	/* generate the checksum. */
3425	xfs_dinode_calc_crc(mp, dip);
3426
3427	ASSERT(bp->b_fspriv != NULL);
3428	ASSERT(bp->b_iodone != NULL);
3429	return 0;
3430
3431corrupt_out:
3432	return XFS_ERROR(EFSCORRUPTED);
3433}
v4.10.11
   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#include <linux/log2.h>
  19
  20#include "xfs.h"
  21#include "xfs_fs.h"
  22#include "xfs_shared.h"
  23#include "xfs_format.h"
  24#include "xfs_log_format.h"
  25#include "xfs_trans_resv.h"
 
  26#include "xfs_sb.h"
 
  27#include "xfs_mount.h"
  28#include "xfs_defer.h"
  29#include "xfs_inode.h"
  30#include "xfs_da_format.h"
  31#include "xfs_da_btree.h"
  32#include "xfs_dir2.h"
  33#include "xfs_attr_sf.h"
  34#include "xfs_attr.h"
  35#include "xfs_trans_space.h"
  36#include "xfs_trans.h"
  37#include "xfs_buf_item.h"
  38#include "xfs_inode_item.h"
  39#include "xfs_ialloc.h"
  40#include "xfs_bmap.h"
  41#include "xfs_bmap_util.h"
  42#include "xfs_error.h"
  43#include "xfs_quota.h"
  44#include "xfs_filestream.h"
  45#include "xfs_cksum.h"
  46#include "xfs_trace.h"
  47#include "xfs_icache.h"
  48#include "xfs_symlink.h"
  49#include "xfs_trans_priv.h"
  50#include "xfs_log.h"
  51#include "xfs_bmap_btree.h"
  52#include "xfs_reflink.h"
  53
  54kmem_zone_t *xfs_inode_zone;
  55
  56/*
  57 * Used in xfs_itruncate_extents().  This is the maximum number of extents
  58 * freed from a file in a single transaction.
  59 */
  60#define	XFS_ITRUNC_MAX_EXTENTS	2
  61
  62STATIC int xfs_iflush_int(struct xfs_inode *, struct xfs_buf *);
  63STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
  64STATIC int xfs_iunlink_remove(struct xfs_trans *, struct xfs_inode *);
  65
  66/*
  67 * helper function to extract extent size hint from inode
  68 */
  69xfs_extlen_t
  70xfs_get_extsz_hint(
  71	struct xfs_inode	*ip)
  72{
  73	if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
  74		return ip->i_d.di_extsize;
  75	if (XFS_IS_REALTIME_INODE(ip))
  76		return ip->i_mount->m_sb.sb_rextsize;
  77	return 0;
  78}
  79
  80/*
  81 * Helper function to extract CoW extent size hint from inode.
  82 * Between the extent size hint and the CoW extent size hint, we
  83 * return the greater of the two.  If the value is zero (automatic),
  84 * use the default size.
  85 */
  86xfs_extlen_t
  87xfs_get_cowextsz_hint(
  88	struct xfs_inode	*ip)
  89{
  90	xfs_extlen_t		a, b;
  91
  92	a = 0;
  93	if (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
  94		a = ip->i_d.di_cowextsize;
  95	b = xfs_get_extsz_hint(ip);
  96
  97	a = max(a, b);
  98	if (a == 0)
  99		return XFS_DEFAULT_COWEXTSZ_HINT;
 100	return a;
 101}
 102
 103/*
 104 * These two are wrapper routines around the xfs_ilock() routine used to
 105 * centralize some grungy code.  They are used in places that wish to lock the
 106 * inode solely for reading the extents.  The reason these places can't just
 107 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
 108 * bringing in of the extents from disk for a file in b-tree format.  If the
 109 * inode is in b-tree format, then we need to lock the inode exclusively until
 110 * the extents are read in.  Locking it exclusively all the time would limit
 111 * our parallelism unnecessarily, though.  What we do instead is check to see
 112 * if the extents have been read in yet, and only lock the inode exclusively
 113 * if they have not.
 114 *
 115 * The functions return a value which should be given to the corresponding
 116 * xfs_iunlock() call.
 117 */
 118uint
 119xfs_ilock_data_map_shared(
 120	struct xfs_inode	*ip)
 121{
 122	uint			lock_mode = XFS_ILOCK_SHARED;
 123
 124	if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
 125	    (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
 126		lock_mode = XFS_ILOCK_EXCL;
 127	xfs_ilock(ip, lock_mode);
 128	return lock_mode;
 129}
 130
 131uint
 132xfs_ilock_attr_map_shared(
 133	struct xfs_inode	*ip)
 134{
 135	uint			lock_mode = XFS_ILOCK_SHARED;
 136
 137	if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
 138	    (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
 139		lock_mode = XFS_ILOCK_EXCL;
 140	xfs_ilock(ip, lock_mode);
 141	return lock_mode;
 142}
 143
 144/*
 145 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
 146 * multi-reader locks: i_mmap_lock and the i_lock.  This routine allows
 147 * various combinations of the locks to be obtained.
 148 *
 149 * The 3 locks should always be ordered so that the IO lock is obtained first,
 150 * the mmap lock second and the ilock last in order to prevent deadlock.
 151 *
 152 * Basic locking order:
 153 *
 154 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
 155 *
 156 * mmap_sem locking order:
 157 *
 158 * i_rwsem -> page lock -> mmap_sem
 159 * mmap_sem -> i_mmap_lock -> page_lock
 160 *
 161 * The difference in mmap_sem locking order mean that we cannot hold the
 162 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
 163 * fault in pages during copy in/out (for buffered IO) or require the mmap_sem
 164 * in get_user_pages() to map the user pages into the kernel address space for
 165 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
 166 * page faults already hold the mmap_sem.
 167 *
 168 * Hence to serialise fully against both syscall and mmap based IO, we need to
 169 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
 170 * taken in places where we need to invalidate the page cache in a race
 171 * free manner (e.g. truncate, hole punch and other extent manipulation
 172 * functions).
 173 */
 174void
 175xfs_ilock(
 176	xfs_inode_t		*ip,
 177	uint			lock_flags)
 178{
 179	trace_xfs_ilock(ip, lock_flags, _RET_IP_);
 180
 181	/*
 182	 * You can't set both SHARED and EXCL for the same lock,
 183	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 184	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 185	 */
 186	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 187	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 188	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 189	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 190	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 191	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 192	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 193
 194	if (lock_flags & XFS_IOLOCK_EXCL) {
 195		down_write_nested(&VFS_I(ip)->i_rwsem,
 196				  XFS_IOLOCK_DEP(lock_flags));
 197	} else if (lock_flags & XFS_IOLOCK_SHARED) {
 198		down_read_nested(&VFS_I(ip)->i_rwsem,
 199				 XFS_IOLOCK_DEP(lock_flags));
 200	}
 201
 202	if (lock_flags & XFS_MMAPLOCK_EXCL)
 203		mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
 204	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 205		mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
 206
 207	if (lock_flags & XFS_ILOCK_EXCL)
 208		mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 209	else if (lock_flags & XFS_ILOCK_SHARED)
 210		mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 211}
 212
 213/*
 214 * This is just like xfs_ilock(), except that the caller
 215 * is guaranteed not to sleep.  It returns 1 if it gets
 216 * the requested locks and 0 otherwise.  If the IO lock is
 217 * obtained but the inode lock cannot be, then the IO lock
 218 * is dropped before returning.
 219 *
 220 * ip -- the inode being locked
 221 * lock_flags -- this parameter indicates the inode's locks to be
 222 *       to be locked.  See the comment for xfs_ilock() for a list
 223 *	 of valid values.
 224 */
 225int
 226xfs_ilock_nowait(
 227	xfs_inode_t		*ip,
 228	uint			lock_flags)
 229{
 230	trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
 231
 232	/*
 233	 * You can't set both SHARED and EXCL for the same lock,
 234	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 235	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 236	 */
 237	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 238	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 239	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 240	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 241	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 242	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 243	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 244
 245	if (lock_flags & XFS_IOLOCK_EXCL) {
 246		if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
 247			goto out;
 248	} else if (lock_flags & XFS_IOLOCK_SHARED) {
 249		if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
 250			goto out;
 251	}
 252
 253	if (lock_flags & XFS_MMAPLOCK_EXCL) {
 254		if (!mrtryupdate(&ip->i_mmaplock))
 255			goto out_undo_iolock;
 256	} else if (lock_flags & XFS_MMAPLOCK_SHARED) {
 257		if (!mrtryaccess(&ip->i_mmaplock))
 258			goto out_undo_iolock;
 259	}
 260
 261	if (lock_flags & XFS_ILOCK_EXCL) {
 262		if (!mrtryupdate(&ip->i_lock))
 263			goto out_undo_mmaplock;
 264	} else if (lock_flags & XFS_ILOCK_SHARED) {
 265		if (!mrtryaccess(&ip->i_lock))
 266			goto out_undo_mmaplock;
 267	}
 268	return 1;
 269
 270out_undo_mmaplock:
 271	if (lock_flags & XFS_MMAPLOCK_EXCL)
 272		mrunlock_excl(&ip->i_mmaplock);
 273	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 274		mrunlock_shared(&ip->i_mmaplock);
 275out_undo_iolock:
 276	if (lock_flags & XFS_IOLOCK_EXCL)
 277		up_write(&VFS_I(ip)->i_rwsem);
 278	else if (lock_flags & XFS_IOLOCK_SHARED)
 279		up_read(&VFS_I(ip)->i_rwsem);
 280out:
 281	return 0;
 282}
 283
 284/*
 285 * xfs_iunlock() is used to drop the inode locks acquired with
 286 * xfs_ilock() and xfs_ilock_nowait().  The caller must pass
 287 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
 288 * that we know which locks to drop.
 289 *
 290 * ip -- the inode being unlocked
 291 * lock_flags -- this parameter indicates the inode's locks to be
 292 *       to be unlocked.  See the comment for xfs_ilock() for a list
 293 *	 of valid values for this parameter.
 294 *
 295 */
 296void
 297xfs_iunlock(
 298	xfs_inode_t		*ip,
 299	uint			lock_flags)
 300{
 301	/*
 302	 * You can't set both SHARED and EXCL for the same lock,
 303	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 304	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 305	 */
 306	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 307	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 308	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 309	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 310	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 311	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 312	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 313	ASSERT(lock_flags != 0);
 314
 315	if (lock_flags & XFS_IOLOCK_EXCL)
 316		up_write(&VFS_I(ip)->i_rwsem);
 317	else if (lock_flags & XFS_IOLOCK_SHARED)
 318		up_read(&VFS_I(ip)->i_rwsem);
 319
 320	if (lock_flags & XFS_MMAPLOCK_EXCL)
 321		mrunlock_excl(&ip->i_mmaplock);
 322	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 323		mrunlock_shared(&ip->i_mmaplock);
 324
 325	if (lock_flags & XFS_ILOCK_EXCL)
 326		mrunlock_excl(&ip->i_lock);
 327	else if (lock_flags & XFS_ILOCK_SHARED)
 328		mrunlock_shared(&ip->i_lock);
 329
 330	trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
 331}
 332
 333/*
 334 * give up write locks.  the i/o lock cannot be held nested
 335 * if it is being demoted.
 336 */
 337void
 338xfs_ilock_demote(
 339	xfs_inode_t		*ip,
 340	uint			lock_flags)
 341{
 342	ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
 343	ASSERT((lock_flags &
 344		~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
 345
 346	if (lock_flags & XFS_ILOCK_EXCL)
 347		mrdemote(&ip->i_lock);
 348	if (lock_flags & XFS_MMAPLOCK_EXCL)
 349		mrdemote(&ip->i_mmaplock);
 350	if (lock_flags & XFS_IOLOCK_EXCL)
 351		downgrade_write(&VFS_I(ip)->i_rwsem);
 352
 353	trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
 354}
 355
 356#if defined(DEBUG) || defined(XFS_WARN)
 357int
 358xfs_isilocked(
 359	xfs_inode_t		*ip,
 360	uint			lock_flags)
 361{
 362	if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
 363		if (!(lock_flags & XFS_ILOCK_SHARED))
 364			return !!ip->i_lock.mr_writer;
 365		return rwsem_is_locked(&ip->i_lock.mr_lock);
 366	}
 367
 368	if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
 369		if (!(lock_flags & XFS_MMAPLOCK_SHARED))
 370			return !!ip->i_mmaplock.mr_writer;
 371		return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
 372	}
 373
 374	if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
 375		if (!(lock_flags & XFS_IOLOCK_SHARED))
 376			return !debug_locks ||
 377				lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
 378		return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
 379	}
 380
 381	ASSERT(0);
 382	return 0;
 383}
 384#endif
 385
 386#ifdef DEBUG
 387int xfs_locked_n;
 388int xfs_small_retries;
 389int xfs_middle_retries;
 390int xfs_lots_retries;
 391int xfs_lock_delays;
 392#endif
 393
 394/*
 395 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
 396 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
 397 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
 398 * errors and warnings.
 399 */
 400#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
 401static bool
 402xfs_lockdep_subclass_ok(
 403	int subclass)
 404{
 405	return subclass < MAX_LOCKDEP_SUBCLASSES;
 406}
 407#else
 408#define xfs_lockdep_subclass_ok(subclass)	(true)
 409#endif
 410
 411/*
 412 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
 413 * value. This can be called for any type of inode lock combination, including
 414 * parent locking. Care must be taken to ensure we don't overrun the subclass
 415 * storage fields in the class mask we build.
 416 */
 417static inline int
 418xfs_lock_inumorder(int lock_mode, int subclass)
 419{
 420	int	class = 0;
 
 
 
 421
 422	ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
 423			      XFS_ILOCK_RTSUM)));
 424	ASSERT(xfs_lockdep_subclass_ok(subclass));
 425
 426	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
 427		ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
 428		class += subclass << XFS_IOLOCK_SHIFT;
 429	}
 430
 431	if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
 432		ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
 433		class += subclass << XFS_MMAPLOCK_SHIFT;
 434	}
 435
 436	if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
 437		ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
 438		class += subclass << XFS_ILOCK_SHIFT;
 439	}
 440
 441	return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
 442}
 443
 444/*
 445 * The following routine will lock n inodes in exclusive mode.  We assume the
 446 * caller calls us with the inodes in i_ino order.
 447 *
 448 * We need to detect deadlock where an inode that we lock is in the AIL and we
 449 * start waiting for another inode that is locked by a thread in a long running
 450 * transaction (such as truncate). This can result in deadlock since the long
 451 * running trans might need to wait for the inode we just locked in order to
 452 * push the tail and free space in the log.
 453 *
 454 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
 455 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
 456 * lock more than one at a time, lockdep will report false positives saying we
 457 * have violated locking orders.
 458 */
 459static void
 460xfs_lock_inodes(
 461	xfs_inode_t	**ips,
 462	int		inodes,
 463	uint		lock_mode)
 464{
 465	int		attempts = 0, i, j, try_lock;
 466	xfs_log_item_t	*lp;
 467
 468	/*
 469	 * Currently supports between 2 and 5 inodes with exclusive locking.  We
 470	 * support an arbitrary depth of locking here, but absolute limits on
 471	 * inodes depend on the the type of locking and the limits placed by
 472	 * lockdep annotations in xfs_lock_inumorder.  These are all checked by
 473	 * the asserts.
 474	 */
 475	ASSERT(ips && inodes >= 2 && inodes <= 5);
 476	ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
 477			    XFS_ILOCK_EXCL));
 478	ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
 479			      XFS_ILOCK_SHARED)));
 480	ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
 481		inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
 482	ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
 483		inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
 484
 485	if (lock_mode & XFS_IOLOCK_EXCL) {
 486		ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
 487	} else if (lock_mode & XFS_MMAPLOCK_EXCL)
 488		ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
 489
 490	try_lock = 0;
 491	i = 0;
 
 492again:
 493	for (; i < inodes; i++) {
 494		ASSERT(ips[i]);
 495
 496		if (i && (ips[i] == ips[i - 1]))	/* Already locked */
 497			continue;
 498
 499		/*
 500		 * If try_lock is not set yet, make sure all locked inodes are
 501		 * not in the AIL.  If any are, set try_lock to be used later.
 
 502		 */
 
 503		if (!try_lock) {
 504			for (j = (i - 1); j >= 0 && !try_lock; j--) {
 505				lp = (xfs_log_item_t *)ips[j]->i_itemp;
 506				if (lp && (lp->li_flags & XFS_LI_IN_AIL))
 507					try_lock++;
 
 508			}
 509		}
 510
 511		/*
 512		 * If any of the previous locks we have locked is in the AIL,
 513		 * we must TRY to get the second and subsequent locks. If
 514		 * we can't get any, we must release all we have
 515		 * and try again.
 516		 */
 517		if (!try_lock) {
 518			xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
 519			continue;
 520		}
 521
 522		/* try_lock means we have an inode locked that is in the AIL. */
 523		ASSERT(i != 0);
 524		if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
 525			continue;
 526
 527		/*
 528		 * Unlock all previous guys and try again.  xfs_iunlock will try
 529		 * to push the tail if the inode is in the AIL.
 530		 */
 531		attempts++;
 532		for (j = i - 1; j >= 0; j--) {
 533			/*
 534			 * Check to see if we've already unlocked this one.  Not
 535			 * the first one going back, and the inode ptr is the
 536			 * same.
 537			 */
 538			if (j != (i - 1) && ips[j] == ips[j + 1])
 539				continue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 540
 541			xfs_iunlock(ips[j], lock_mode);
 542		}
 543
 544		if ((attempts % 5) == 0) {
 545			delay(1); /* Don't just spin the CPU */
 546#ifdef DEBUG
 547			xfs_lock_delays++;
 548#endif
 
 
 
 
 
 
 
 549		}
 550		i = 0;
 551		try_lock = 0;
 552		goto again;
 553	}
 554
 555#ifdef DEBUG
 556	if (attempts) {
 557		if (attempts < 5) xfs_small_retries++;
 558		else if (attempts < 100) xfs_middle_retries++;
 559		else xfs_lots_retries++;
 560	} else {
 561		xfs_locked_n++;
 562	}
 563#endif
 564}
 565
 566/*
 567 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
 568 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
 569 * lock more than one at a time, lockdep will report false positives saying we
 570 * have violated locking orders.
 571 */
 572void
 573xfs_lock_two_inodes(
 574	xfs_inode_t		*ip0,
 575	xfs_inode_t		*ip1,
 576	uint			lock_mode)
 577{
 578	xfs_inode_t		*temp;
 579	int			attempts = 0;
 580	xfs_log_item_t		*lp;
 581
 582	ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
 583	if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL))
 584		ASSERT(!(lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 585
 586	ASSERT(ip0->i_ino != ip1->i_ino);
 587
 588	if (ip0->i_ino > ip1->i_ino) {
 589		temp = ip0;
 590		ip0 = ip1;
 591		ip1 = temp;
 592	}
 593
 594 again:
 595	xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0));
 596
 597	/*
 598	 * If the first lock we have locked is in the AIL, we must TRY to get
 599	 * the second lock. If we can't get it, we must release the first one
 600	 * and try again.
 601	 */
 602	lp = (xfs_log_item_t *)ip0->i_itemp;
 603	if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
 604		if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) {
 605			xfs_iunlock(ip0, lock_mode);
 606			if ((++attempts % 5) == 0)
 607				delay(1); /* Don't just spin the CPU */
 608			goto again;
 609		}
 610	} else {
 611		xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1));
 612	}
 613}
 614
 615
 616void
 617__xfs_iflock(
 618	struct xfs_inode	*ip)
 619{
 620	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
 621	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
 622
 623	do {
 624		prepare_to_wait_exclusive(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
 625		if (xfs_isiflocked(ip))
 626			io_schedule();
 627	} while (!xfs_iflock_nowait(ip));
 628
 629	finish_wait(wq, &wait.wait);
 630}
 631
 632STATIC uint
 633_xfs_dic2xflags(
 634	__uint16_t		di_flags,
 635	uint64_t		di_flags2,
 636	bool			has_attr)
 637{
 638	uint			flags = 0;
 639
 640	if (di_flags & XFS_DIFLAG_ANY) {
 641		if (di_flags & XFS_DIFLAG_REALTIME)
 642			flags |= FS_XFLAG_REALTIME;
 643		if (di_flags & XFS_DIFLAG_PREALLOC)
 644			flags |= FS_XFLAG_PREALLOC;
 645		if (di_flags & XFS_DIFLAG_IMMUTABLE)
 646			flags |= FS_XFLAG_IMMUTABLE;
 647		if (di_flags & XFS_DIFLAG_APPEND)
 648			flags |= FS_XFLAG_APPEND;
 649		if (di_flags & XFS_DIFLAG_SYNC)
 650			flags |= FS_XFLAG_SYNC;
 651		if (di_flags & XFS_DIFLAG_NOATIME)
 652			flags |= FS_XFLAG_NOATIME;
 653		if (di_flags & XFS_DIFLAG_NODUMP)
 654			flags |= FS_XFLAG_NODUMP;
 655		if (di_flags & XFS_DIFLAG_RTINHERIT)
 656			flags |= FS_XFLAG_RTINHERIT;
 657		if (di_flags & XFS_DIFLAG_PROJINHERIT)
 658			flags |= FS_XFLAG_PROJINHERIT;
 659		if (di_flags & XFS_DIFLAG_NOSYMLINKS)
 660			flags |= FS_XFLAG_NOSYMLINKS;
 661		if (di_flags & XFS_DIFLAG_EXTSIZE)
 662			flags |= FS_XFLAG_EXTSIZE;
 663		if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
 664			flags |= FS_XFLAG_EXTSZINHERIT;
 665		if (di_flags & XFS_DIFLAG_NODEFRAG)
 666			flags |= FS_XFLAG_NODEFRAG;
 667		if (di_flags & XFS_DIFLAG_FILESTREAM)
 668			flags |= FS_XFLAG_FILESTREAM;
 669	}
 670
 671	if (di_flags2 & XFS_DIFLAG2_ANY) {
 672		if (di_flags2 & XFS_DIFLAG2_DAX)
 673			flags |= FS_XFLAG_DAX;
 674		if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
 675			flags |= FS_XFLAG_COWEXTSIZE;
 676	}
 677
 678	if (has_attr)
 679		flags |= FS_XFLAG_HASATTR;
 680
 681	return flags;
 682}
 683
 684uint
 685xfs_ip2xflags(
 686	struct xfs_inode	*ip)
 687{
 688	struct xfs_icdinode	*dic = &ip->i_d;
 689
 690	return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip));
 
 
 
 
 
 
 
 
 
 691}
 692
 693/*
 694 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
 695 * is allowed, otherwise it has to be an exact match. If a CI match is found,
 696 * ci_name->name will point to a the actual name (caller must free) or
 697 * will be set to NULL if an exact match is found.
 698 */
 699int
 700xfs_lookup(
 701	xfs_inode_t		*dp,
 702	struct xfs_name		*name,
 703	xfs_inode_t		**ipp,
 704	struct xfs_name		*ci_name)
 705{
 706	xfs_ino_t		inum;
 707	int			error;
 
 708
 709	trace_xfs_lookup(dp, name);
 710
 711	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
 712		return -EIO;
 713
 
 714	error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
 
 
 715	if (error)
 716		goto out_unlock;
 717
 718	error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
 719	if (error)
 720		goto out_free_name;
 721
 722	return 0;
 723
 724out_free_name:
 725	if (ci_name)
 726		kmem_free(ci_name->name);
 727out_unlock:
 728	*ipp = NULL;
 729	return error;
 730}
 731
 732/*
 733 * Allocate an inode on disk and return a copy of its in-core version.
 734 * The in-core inode is locked exclusively.  Set mode, nlink, and rdev
 735 * appropriately within the inode.  The uid and gid for the inode are
 736 * set according to the contents of the given cred structure.
 737 *
 738 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
 739 * has a free inode available, call xfs_iget() to obtain the in-core
 740 * version of the allocated inode.  Finally, fill in the inode and
 741 * log its initial contents.  In this case, ialloc_context would be
 742 * set to NULL.
 743 *
 744 * If xfs_dialloc() does not have an available inode, it will replenish
 745 * its supply by doing an allocation. Since we can only do one
 746 * allocation within a transaction without deadlocks, we must commit
 747 * the current transaction before returning the inode itself.
 748 * In this case, therefore, we will set ialloc_context and return.
 749 * The caller should then commit the current transaction, start a new
 750 * transaction, and call xfs_ialloc() again to actually get the inode.
 751 *
 752 * To ensure that some other process does not grab the inode that
 753 * was allocated during the first call to xfs_ialloc(), this routine
 754 * also returns the [locked] bp pointing to the head of the freelist
 755 * as ialloc_context.  The caller should hold this buffer across
 756 * the commit and pass it back into this routine on the second call.
 757 *
 758 * If we are allocating quota inodes, we do not have a parent inode
 759 * to attach to or associate with (i.e. pip == NULL) because they
 760 * are not linked into the directory structure - they are attached
 761 * directly to the superblock - and so have no parent.
 762 */
 763static int
 764xfs_ialloc(
 765	xfs_trans_t	*tp,
 766	xfs_inode_t	*pip,
 767	umode_t		mode,
 768	xfs_nlink_t	nlink,
 769	xfs_dev_t	rdev,
 770	prid_t		prid,
 771	int		okalloc,
 772	xfs_buf_t	**ialloc_context,
 773	xfs_inode_t	**ipp)
 774{
 775	struct xfs_mount *mp = tp->t_mountp;
 776	xfs_ino_t	ino;
 777	xfs_inode_t	*ip;
 778	uint		flags;
 779	int		error;
 780	struct timespec	tv;
 781	struct inode	*inode;
 782
 783	/*
 784	 * Call the space management code to pick
 785	 * the on-disk inode to be allocated.
 786	 */
 787	error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
 788			    ialloc_context, &ino);
 789	if (error)
 790		return error;
 791	if (*ialloc_context || ino == NULLFSINO) {
 792		*ipp = NULL;
 793		return 0;
 794	}
 795	ASSERT(*ialloc_context == NULL);
 796
 797	/*
 798	 * Get the in-core inode with the lock held exclusively.
 799	 * This is because we're setting fields here we need
 800	 * to prevent others from looking at until we're done.
 801	 */
 802	error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
 803			 XFS_ILOCK_EXCL, &ip);
 804	if (error)
 805		return error;
 806	ASSERT(ip != NULL);
 807	inode = VFS_I(ip);
 
 
 
 
 
 
 
 
 808
 809	/*
 810	 * We always convert v1 inodes to v2 now - we only support filesystems
 811	 * with >= v2 inode capability, so there is no reason for ever leaving
 812	 * an inode in v1 format.
 
 813	 */
 814	if (ip->i_d.di_version == 1)
 
 815		ip->i_d.di_version = 2;
 
 
 
 
 
 816
 817	inode->i_mode = mode;
 818	set_nlink(inode, nlink);
 819	ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
 820	ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
 821	xfs_set_projid(ip, prid);
 822
 823	if (pip && XFS_INHERIT_GID(pip)) {
 824		ip->i_d.di_gid = pip->i_d.di_gid;
 825		if ((VFS_I(pip)->i_mode & S_ISGID) && S_ISDIR(mode))
 826			inode->i_mode |= S_ISGID;
 
 827	}
 828
 829	/*
 830	 * If the group ID of the new file does not match the effective group
 831	 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
 832	 * (and only if the irix_sgid_inherit compatibility variable is set).
 833	 */
 834	if ((irix_sgid_inherit) &&
 835	    (inode->i_mode & S_ISGID) &&
 836	    (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid))))
 837		inode->i_mode &= ~S_ISGID;
 
 838
 839	ip->i_d.di_size = 0;
 840	ip->i_d.di_nextents = 0;
 841	ASSERT(ip->i_d.di_nblocks == 0);
 842
 843	tv = current_time(inode);
 844	inode->i_mtime = tv;
 845	inode->i_atime = tv;
 846	inode->i_ctime = tv;
 
 847
 
 
 
 848	ip->i_d.di_extsize = 0;
 849	ip->i_d.di_dmevmask = 0;
 850	ip->i_d.di_dmstate = 0;
 851	ip->i_d.di_flags = 0;
 852
 853	if (ip->i_d.di_version == 3) {
 854		inode->i_version = 1;
 
 
 
 
 855		ip->i_d.di_flags2 = 0;
 856		ip->i_d.di_cowextsize = 0;
 857		ip->i_d.di_crtime.t_sec = (__int32_t)tv.tv_sec;
 858		ip->i_d.di_crtime.t_nsec = (__int32_t)tv.tv_nsec;
 859	}
 860
 861
 862	flags = XFS_ILOG_CORE;
 863	switch (mode & S_IFMT) {
 864	case S_IFIFO:
 865	case S_IFCHR:
 866	case S_IFBLK:
 867	case S_IFSOCK:
 868		ip->i_d.di_format = XFS_DINODE_FMT_DEV;
 869		ip->i_df.if_u2.if_rdev = rdev;
 870		ip->i_df.if_flags = 0;
 871		flags |= XFS_ILOG_DEV;
 872		break;
 873	case S_IFREG:
 
 
 
 
 
 
 
 874	case S_IFDIR:
 875		if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
 876			uint64_t	di_flags2 = 0;
 877			uint		di_flags = 0;
 878
 879			if (S_ISDIR(mode)) {
 880				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
 881					di_flags |= XFS_DIFLAG_RTINHERIT;
 882				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
 883					di_flags |= XFS_DIFLAG_EXTSZINHERIT;
 884					ip->i_d.di_extsize = pip->i_d.di_extsize;
 885				}
 886				if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
 887					di_flags |= XFS_DIFLAG_PROJINHERIT;
 888			} else if (S_ISREG(mode)) {
 889				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
 890					di_flags |= XFS_DIFLAG_REALTIME;
 891				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
 892					di_flags |= XFS_DIFLAG_EXTSIZE;
 893					ip->i_d.di_extsize = pip->i_d.di_extsize;
 894				}
 895			}
 896			if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
 897			    xfs_inherit_noatime)
 898				di_flags |= XFS_DIFLAG_NOATIME;
 899			if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
 900			    xfs_inherit_nodump)
 901				di_flags |= XFS_DIFLAG_NODUMP;
 902			if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
 903			    xfs_inherit_sync)
 904				di_flags |= XFS_DIFLAG_SYNC;
 905			if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
 906			    xfs_inherit_nosymlinks)
 907				di_flags |= XFS_DIFLAG_NOSYMLINKS;
 
 
 908			if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
 909			    xfs_inherit_nodefrag)
 910				di_flags |= XFS_DIFLAG_NODEFRAG;
 911			if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
 912				di_flags |= XFS_DIFLAG_FILESTREAM;
 913			if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
 914				di_flags2 |= XFS_DIFLAG2_DAX;
 915
 916			ip->i_d.di_flags |= di_flags;
 917			ip->i_d.di_flags2 |= di_flags2;
 918		}
 919		if (pip &&
 920		    (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY) &&
 921		    pip->i_d.di_version == 3 &&
 922		    ip->i_d.di_version == 3) {
 923			if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
 924				ip->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
 925				ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
 926			}
 927		}
 928		/* FALLTHROUGH */
 929	case S_IFLNK:
 930		ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
 931		ip->i_df.if_flags = XFS_IFEXTENTS;
 932		ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
 933		ip->i_df.if_u1.if_extents = NULL;
 934		break;
 935	default:
 936		ASSERT(0);
 937	}
 938	/*
 939	 * Attribute fork settings for new inode.
 940	 */
 941	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
 942	ip->i_d.di_anextents = 0;
 943
 944	/*
 945	 * Log the new values stuffed into the inode.
 946	 */
 947	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 948	xfs_trans_log_inode(tp, ip, flags);
 949
 950	/* now that we have an i_mode we can setup the inode structure */
 951	xfs_setup_inode(ip);
 952
 
 
 
 
 
 
 
 
 
 953	*ipp = ip;
 954	return 0;
 955}
 956
 957/*
 958 * Allocates a new inode from disk and return a pointer to the
 959 * incore copy. This routine will internally commit the current
 960 * transaction and allocate a new one if the Space Manager needed
 961 * to do an allocation to replenish the inode free-list.
 962 *
 963 * This routine is designed to be called from xfs_create and
 964 * xfs_create_dir.
 965 *
 966 */
 967int
 968xfs_dir_ialloc(
 969	xfs_trans_t	**tpp,		/* input: current transaction;
 970					   output: may be a new transaction. */
 971	xfs_inode_t	*dp,		/* directory within whose allocate
 972					   the inode. */
 973	umode_t		mode,
 974	xfs_nlink_t	nlink,
 975	xfs_dev_t	rdev,
 976	prid_t		prid,		/* project id */
 977	int		okalloc,	/* ok to allocate new space */
 978	xfs_inode_t	**ipp,		/* pointer to inode; it will be
 979					   locked. */
 980	int		*committed)
 981
 982{
 983	xfs_trans_t	*tp;
 
 984	xfs_inode_t	*ip;
 985	xfs_buf_t	*ialloc_context = NULL;
 986	int		code;
 987	void		*dqinfo;
 988	uint		tflags;
 989
 990	tp = *tpp;
 991	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
 992
 993	/*
 994	 * xfs_ialloc will return a pointer to an incore inode if
 995	 * the Space Manager has an available inode on the free
 996	 * list. Otherwise, it will do an allocation and replenish
 997	 * the freelist.  Since we can only do one allocation per
 998	 * transaction without deadlocks, we will need to commit the
 999	 * current transaction and start a new one.  We will then
1000	 * need to call xfs_ialloc again to get the inode.
1001	 *
1002	 * If xfs_ialloc did an allocation to replenish the freelist,
1003	 * it returns the bp containing the head of the freelist as
1004	 * ialloc_context. We will hold a lock on it across the
1005	 * transaction commit so that no other process can steal
1006	 * the inode(s) that we've just allocated.
1007	 */
1008	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
1009			  &ialloc_context, &ip);
1010
1011	/*
1012	 * Return an error if we were unable to allocate a new inode.
1013	 * This should only happen if we run out of space on disk or
1014	 * encounter a disk error.
1015	 */
1016	if (code) {
1017		*ipp = NULL;
1018		return code;
1019	}
1020	if (!ialloc_context && !ip) {
1021		*ipp = NULL;
1022		return -ENOSPC;
1023	}
1024
1025	/*
1026	 * If the AGI buffer is non-NULL, then we were unable to get an
1027	 * inode in one operation.  We need to commit the current
1028	 * transaction and call xfs_ialloc() again.  It is guaranteed
1029	 * to succeed the second time.
1030	 */
1031	if (ialloc_context) {
 
 
1032		/*
1033		 * Normally, xfs_trans_commit releases all the locks.
1034		 * We call bhold to hang on to the ialloc_context across
1035		 * the commit.  Holding this buffer prevents any other
1036		 * processes from doing any allocations in this
1037		 * allocation group.
1038		 */
1039		xfs_trans_bhold(tp, ialloc_context);
 
 
 
 
 
 
1040
1041		/*
1042		 * We want the quota changes to be associated with the next
1043		 * transaction, NOT this one. So, detach the dqinfo from this
1044		 * and attach it to the next transaction.
1045		 */
1046		dqinfo = NULL;
1047		tflags = 0;
1048		if (tp->t_dqinfo) {
1049			dqinfo = (void *)tp->t_dqinfo;
1050			tp->t_dqinfo = NULL;
1051			tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
1052			tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
1053		}
1054
1055		code = xfs_trans_roll(&tp, NULL);
1056		if (committed != NULL)
 
 
1057			*committed = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1058
1059		/*
1060		 * Re-attach the quota info that we detached from prev trx.
1061		 */
1062		if (dqinfo) {
1063			tp->t_dqinfo = dqinfo;
1064			tp->t_flags |= tflags;
1065		}
1066
1067		if (code) {
1068			xfs_buf_relse(ialloc_context);
1069			*tpp = tp;
1070			*ipp = NULL;
1071			return code;
1072		}
1073		xfs_trans_bjoin(tp, ialloc_context);
1074
1075		/*
1076		 * Call ialloc again. Since we've locked out all
1077		 * other allocations in this allocation group,
1078		 * this call should always succeed.
1079		 */
1080		code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1081				  okalloc, &ialloc_context, &ip);
1082
1083		/*
1084		 * If we get an error at this point, return to the caller
1085		 * so that the current transaction can be aborted.
1086		 */
1087		if (code) {
1088			*tpp = tp;
1089			*ipp = NULL;
1090			return code;
1091		}
1092		ASSERT(!ialloc_context && ip);
1093
1094	} else {
1095		if (committed != NULL)
1096			*committed = 0;
1097	}
1098
1099	*ipp = ip;
1100	*tpp = tp;
1101
1102	return 0;
1103}
1104
1105/*
1106 * Decrement the link count on an inode & log the change.  If this causes the
1107 * link count to go to zero, move the inode to AGI unlinked list so that it can
1108 * be freed when the last active reference goes away via xfs_inactive().
1109 */
1110static int			/* error */
1111xfs_droplink(
1112	xfs_trans_t *tp,
1113	xfs_inode_t *ip)
1114{
 
 
1115	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1116
 
 
1117	drop_nlink(VFS_I(ip));
1118	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1119
1120	if (VFS_I(ip)->i_nlink)
1121		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1122
1123	return xfs_iunlink(tp, ip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1124}
1125
1126/*
1127 * Increment the link count on an inode & log the change.
1128 */
1129static int
1130xfs_bumplink(
1131	xfs_trans_t *tp,
1132	xfs_inode_t *ip)
1133{
1134	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1135
1136	ASSERT(ip->i_d.di_version > 1);
 
1137	inc_nlink(VFS_I(ip));
 
 
 
 
 
 
 
 
 
 
 
 
 
1138	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1139	return 0;
1140}
1141
1142int
1143xfs_create(
1144	xfs_inode_t		*dp,
1145	struct xfs_name		*name,
1146	umode_t			mode,
1147	xfs_dev_t		rdev,
1148	xfs_inode_t		**ipp)
1149{
1150	int			is_dir = S_ISDIR(mode);
1151	struct xfs_mount	*mp = dp->i_mount;
1152	struct xfs_inode	*ip = NULL;
1153	struct xfs_trans	*tp = NULL;
1154	int			error;
1155	struct xfs_defer_ops	dfops;
1156	xfs_fsblock_t		first_block;
1157	bool                    unlock_dp_on_error = false;
 
 
1158	prid_t			prid;
1159	struct xfs_dquot	*udqp = NULL;
1160	struct xfs_dquot	*gdqp = NULL;
1161	struct xfs_dquot	*pdqp = NULL;
1162	struct xfs_trans_res	*tres;
1163	uint			resblks;
1164
1165	trace_xfs_create(dp, name);
1166
1167	if (XFS_FORCED_SHUTDOWN(mp))
1168		return -EIO;
1169
1170	prid = xfs_get_initial_prid(dp);
1171
1172	/*
1173	 * Make sure that we have allocated dquot(s) on disk.
1174	 */
1175	error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1176					xfs_kgid_to_gid(current_fsgid()), prid,
1177					XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1178					&udqp, &gdqp, &pdqp);
1179	if (error)
1180		return error;
1181
1182	if (is_dir) {
1183		rdev = 0;
1184		resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1185		tres = &M_RES(mp)->tr_mkdir;
 
 
1186	} else {
1187		resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1188		tres = &M_RES(mp)->tr_create;
 
 
1189	}
1190
 
 
1191	/*
1192	 * Initially assume that the file does not exist and
1193	 * reserve the resources for that case.  If that is not
1194	 * the case we'll drop the one we have and get a more
1195	 * appropriate transaction later.
1196	 */
1197	error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1198	if (error == -ENOSPC) {
 
1199		/* flush outstanding delalloc blocks and retry */
1200		xfs_flush_inodes(mp);
1201		error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1202	}
1203	if (error == -ENOSPC) {
1204		/* No space at all so try a "no-allocation" reservation */
1205		resblks = 0;
1206		error = xfs_trans_alloc(mp, tres, 0, 0, 0, &tp);
 
 
 
 
1207	}
1208	if (error)
1209		goto out_release_inode;
1210
1211	xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1212	unlock_dp_on_error = true;
1213
1214	xfs_defer_init(&dfops, &first_block);
1215
1216	/*
1217	 * Reserve disk quota and the inode.
1218	 */
1219	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1220						pdqp, resblks, 1, 0);
1221	if (error)
1222		goto out_trans_cancel;
1223
1224	if (!resblks) {
1225		error = xfs_dir_canenter(tp, dp, name);
1226		if (error)
1227			goto out_trans_cancel;
1228	}
1229
1230	/*
1231	 * A newly created regular or special file just has one directory
1232	 * entry pointing to them, but a directory also the "." entry
1233	 * pointing to itself.
1234	 */
1235	error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
1236			       prid, resblks > 0, &ip, NULL);
1237	if (error)
1238		goto out_trans_cancel;
 
 
 
1239
1240	/*
1241	 * Now we join the directory inode to the transaction.  We do not do it
1242	 * earlier because xfs_dir_ialloc might commit the previous transaction
1243	 * (and release all the locks).  An error from here on will result in
1244	 * the transaction cancel unlocking dp so don't do it explicitly in the
1245	 * error path.
1246	 */
1247	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1248	unlock_dp_on_error = false;
1249
1250	error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1251					&first_block, &dfops, resblks ?
1252					resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1253	if (error) {
1254		ASSERT(error != -ENOSPC);
1255		goto out_trans_cancel;
1256	}
1257	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1258	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1259
1260	if (is_dir) {
1261		error = xfs_dir_init(tp, ip, dp);
1262		if (error)
1263			goto out_bmap_cancel;
1264
1265		error = xfs_bumplink(tp, dp);
1266		if (error)
1267			goto out_bmap_cancel;
1268	}
1269
1270	/*
1271	 * If this is a synchronous mount, make sure that the
1272	 * create transaction goes to disk before returning to
1273	 * the user.
1274	 */
1275	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1276		xfs_trans_set_sync(tp);
1277
1278	/*
1279	 * Attach the dquot(s) to the inodes and modify them incore.
1280	 * These ids of the inode couldn't have changed since the new
1281	 * inode has been locked ever since it was created.
1282	 */
1283	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1284
1285	error = xfs_defer_finish(&tp, &dfops, NULL);
1286	if (error)
1287		goto out_bmap_cancel;
1288
1289	error = xfs_trans_commit(tp);
1290	if (error)
1291		goto out_release_inode;
1292
1293	xfs_qm_dqrele(udqp);
1294	xfs_qm_dqrele(gdqp);
1295	xfs_qm_dqrele(pdqp);
1296
1297	*ipp = ip;
1298	return 0;
1299
1300 out_bmap_cancel:
1301	xfs_defer_cancel(&dfops);
 
 
1302 out_trans_cancel:
1303	xfs_trans_cancel(tp);
1304 out_release_inode:
1305	/*
1306	 * Wait until after the current transaction is aborted to finish the
1307	 * setup of the inode and release the inode.  This prevents recursive
1308	 * transactions and deadlocks from xfs_inactive.
1309	 */
1310	if (ip) {
1311		xfs_finish_inode_setup(ip);
1312		IRELE(ip);
1313	}
1314
1315	xfs_qm_dqrele(udqp);
1316	xfs_qm_dqrele(gdqp);
1317	xfs_qm_dqrele(pdqp);
1318
1319	if (unlock_dp_on_error)
1320		xfs_iunlock(dp, XFS_ILOCK_EXCL);
1321	return error;
1322}
1323
1324int
1325xfs_create_tmpfile(
1326	struct xfs_inode	*dp,
1327	struct dentry		*dentry,
1328	umode_t			mode,
1329	struct xfs_inode	**ipp)
1330{
1331	struct xfs_mount	*mp = dp->i_mount;
1332	struct xfs_inode	*ip = NULL;
1333	struct xfs_trans	*tp = NULL;
1334	int			error;
 
1335	prid_t                  prid;
1336	struct xfs_dquot	*udqp = NULL;
1337	struct xfs_dquot	*gdqp = NULL;
1338	struct xfs_dquot	*pdqp = NULL;
1339	struct xfs_trans_res	*tres;
1340	uint			resblks;
1341
1342	if (XFS_FORCED_SHUTDOWN(mp))
1343		return -EIO;
1344
1345	prid = xfs_get_initial_prid(dp);
1346
1347	/*
1348	 * Make sure that we have allocated dquot(s) on disk.
1349	 */
1350	error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1351				xfs_kgid_to_gid(current_fsgid()), prid,
1352				XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1353				&udqp, &gdqp, &pdqp);
1354	if (error)
1355		return error;
1356
1357	resblks = XFS_IALLOC_SPACE_RES(mp);
 
 
1358	tres = &M_RES(mp)->tr_create_tmpfile;
1359
1360	error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1361	if (error == -ENOSPC) {
1362		/* No space at all so try a "no-allocation" reservation */
1363		resblks = 0;
1364		error = xfs_trans_alloc(mp, tres, 0, 0, 0, &tp);
 
 
 
 
1365	}
1366	if (error)
1367		goto out_release_inode;
1368
1369	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1370						pdqp, resblks, 1, 0);
1371	if (error)
1372		goto out_trans_cancel;
1373
1374	error = xfs_dir_ialloc(&tp, dp, mode, 1, 0,
1375				prid, resblks > 0, &ip, NULL);
1376	if (error)
1377		goto out_trans_cancel;
 
 
 
1378
1379	if (mp->m_flags & XFS_MOUNT_WSYNC)
1380		xfs_trans_set_sync(tp);
1381
1382	/*
1383	 * Attach the dquot(s) to the inodes and modify them incore.
1384	 * These ids of the inode couldn't have changed since the new
1385	 * inode has been locked ever since it was created.
1386	 */
1387	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1388
 
1389	error = xfs_iunlink(tp, ip);
1390	if (error)
1391		goto out_trans_cancel;
1392
1393	error = xfs_trans_commit(tp);
1394	if (error)
1395		goto out_release_inode;
1396
1397	xfs_qm_dqrele(udqp);
1398	xfs_qm_dqrele(gdqp);
1399	xfs_qm_dqrele(pdqp);
1400
1401	*ipp = ip;
1402	return 0;
1403
 
 
1404 out_trans_cancel:
1405	xfs_trans_cancel(tp);
1406 out_release_inode:
1407	/*
1408	 * Wait until after the current transaction is aborted to finish the
1409	 * setup of the inode and release the inode.  This prevents recursive
1410	 * transactions and deadlocks from xfs_inactive.
1411	 */
1412	if (ip) {
1413		xfs_finish_inode_setup(ip);
1414		IRELE(ip);
1415	}
1416
1417	xfs_qm_dqrele(udqp);
1418	xfs_qm_dqrele(gdqp);
1419	xfs_qm_dqrele(pdqp);
1420
1421	return error;
1422}
1423
1424int
1425xfs_link(
1426	xfs_inode_t		*tdp,
1427	xfs_inode_t		*sip,
1428	struct xfs_name		*target_name)
1429{
1430	xfs_mount_t		*mp = tdp->i_mount;
1431	xfs_trans_t		*tp;
1432	int			error;
1433	struct xfs_defer_ops	dfops;
1434	xfs_fsblock_t           first_block;
 
 
1435	int			resblks;
1436
1437	trace_xfs_link(tdp, target_name);
1438
1439	ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1440
1441	if (XFS_FORCED_SHUTDOWN(mp))
1442		return -EIO;
1443
1444	error = xfs_qm_dqattach(sip, 0);
1445	if (error)
1446		goto std_return;
1447
1448	error = xfs_qm_dqattach(tdp, 0);
1449	if (error)
1450		goto std_return;
1451
 
 
1452	resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1453	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1454	if (error == -ENOSPC) {
1455		resblks = 0;
1456		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
 
 
 
 
1457	}
1458	if (error)
1459		goto std_return;
1460
1461	xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
1462
1463	xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1464	xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1465
1466	/*
1467	 * If we are using project inheritance, we only allow hard link
1468	 * creation in our tree when the project IDs are the same; else
1469	 * the tree quota mechanism could be circumvented.
1470	 */
1471	if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1472		     (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1473		error = -EXDEV;
1474		goto error_return;
1475	}
1476
1477	if (!resblks) {
1478		error = xfs_dir_canenter(tp, tdp, target_name);
1479		if (error)
1480			goto error_return;
1481	}
1482
1483	xfs_defer_init(&dfops, &first_block);
1484
1485	/*
1486	 * Handle initial link state of O_TMPFILE inode
1487	 */
1488	if (VFS_I(sip)->i_nlink == 0) {
1489		error = xfs_iunlink_remove(tp, sip);
1490		if (error)
1491			goto error_return;
1492	}
1493
1494	error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1495					&first_block, &dfops, resblks);
1496	if (error)
1497		goto error_return;
1498	xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1499	xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1500
1501	error = xfs_bumplink(tp, sip);
1502	if (error)
1503		goto error_return;
1504
1505	/*
1506	 * If this is a synchronous mount, make sure that the
1507	 * link transaction goes to disk before returning to
1508	 * the user.
1509	 */
1510	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1511		xfs_trans_set_sync(tp);
 
1512
1513	error = xfs_defer_finish(&tp, &dfops, NULL);
1514	if (error) {
1515		xfs_defer_cancel(&dfops);
1516		goto error_return;
1517	}
1518
1519	return xfs_trans_commit(tp);
1520
 
 
1521 error_return:
1522	xfs_trans_cancel(tp);
1523 std_return:
1524	return error;
1525}
1526
1527/*
1528 * Free up the underlying blocks past new_size.  The new size must be smaller
1529 * than the current size.  This routine can be used both for the attribute and
1530 * data fork, and does not modify the inode size, which is left to the caller.
1531 *
1532 * The transaction passed to this routine must have made a permanent log
1533 * reservation of at least XFS_ITRUNCATE_LOG_RES.  This routine may commit the
1534 * given transaction and start new ones, so make sure everything involved in
1535 * the transaction is tidy before calling here.  Some transaction will be
1536 * returned to the caller to be committed.  The incoming transaction must
1537 * already include the inode, and both inode locks must be held exclusively.
1538 * The inode must also be "held" within the transaction.  On return the inode
1539 * will be "held" within the returned transaction.  This routine does NOT
1540 * require any disk space to be reserved for it within the transaction.
1541 *
1542 * If we get an error, we must return with the inode locked and linked into the
1543 * current transaction. This keeps things simple for the higher level code,
1544 * because it always knows that the inode is locked and held in the transaction
1545 * that returns to it whether errors occur or not.  We don't mark the inode
1546 * dirty on error so that transactions can be easily aborted if possible.
1547 */
1548int
1549xfs_itruncate_extents(
1550	struct xfs_trans	**tpp,
1551	struct xfs_inode	*ip,
1552	int			whichfork,
1553	xfs_fsize_t		new_size)
1554{
1555	struct xfs_mount	*mp = ip->i_mount;
1556	struct xfs_trans	*tp = *tpp;
1557	struct xfs_defer_ops	dfops;
 
1558	xfs_fsblock_t		first_block;
1559	xfs_fileoff_t		first_unmap_block;
1560	xfs_fileoff_t		last_block;
1561	xfs_filblks_t		unmap_len;
 
1562	int			error = 0;
1563	int			done = 0;
1564
1565	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1566	ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1567	       xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1568	ASSERT(new_size <= XFS_ISIZE(ip));
1569	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1570	ASSERT(ip->i_itemp != NULL);
1571	ASSERT(ip->i_itemp->ili_lock_flags == 0);
1572	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1573
1574	trace_xfs_itruncate_extents_start(ip, new_size);
1575
1576	/*
1577	 * Since it is possible for space to become allocated beyond
1578	 * the end of the file (in a crash where the space is allocated
1579	 * but the inode size is not yet updated), simply remove any
1580	 * blocks which show up between the new EOF and the maximum
1581	 * possible file size.  If the first block to be removed is
1582	 * beyond the maximum file size (ie it is the same as last_block),
1583	 * then there is nothing to do.
1584	 */
1585	first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1586	last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1587	if (first_unmap_block == last_block)
1588		return 0;
1589
1590	ASSERT(first_unmap_block < last_block);
1591	unmap_len = last_block - first_unmap_block + 1;
1592	while (!done) {
1593		xfs_defer_init(&dfops, &first_block);
1594		error = xfs_bunmapi(tp, ip,
1595				    first_unmap_block, unmap_len,
1596				    xfs_bmapi_aflag(whichfork),
1597				    XFS_ITRUNC_MAX_EXTENTS,
1598				    &first_block, &dfops,
1599				    &done);
1600		if (error)
1601			goto out_bmap_cancel;
1602
1603		/*
1604		 * Duplicate the transaction that has the permanent
1605		 * reservation and commit the old transaction.
1606		 */
1607		error = xfs_defer_finish(&tp, &dfops, ip);
 
 
1608		if (error)
1609			goto out_bmap_cancel;
1610
1611		error = xfs_trans_roll(&tp, ip);
 
 
 
 
 
 
 
 
 
 
 
 
 
1612		if (error)
1613			goto out;
1614	}
1615
1616	/* Remove all pending CoW reservations. */
1617	error = xfs_reflink_cancel_cow_blocks(ip, &tp, first_unmap_block,
1618			last_block, true);
1619	if (error)
1620		goto out;
1621
1622	/*
1623	 * Clear the reflink flag if we truncated everything.
1624	 */
1625	if (ip->i_d.di_nblocks == 0 && xfs_is_reflink_inode(ip)) {
1626		ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1627		xfs_inode_clear_cowblocks_tag(ip);
1628	}
1629
1630	/*
1631	 * Always re-log the inode so that our permanent transaction can keep
1632	 * on rolling it forward in the log.
1633	 */
1634	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1635
1636	trace_xfs_itruncate_extents_end(ip, new_size);
1637
1638out:
1639	*tpp = tp;
1640	return error;
1641out_bmap_cancel:
1642	/*
1643	 * If the bunmapi call encounters an error, return to the caller where
1644	 * the transaction can be properly aborted.  We just need to make sure
1645	 * we're not holding any resources that we were not when we came in.
1646	 */
1647	xfs_defer_cancel(&dfops);
1648	goto out;
1649}
1650
1651int
1652xfs_release(
1653	xfs_inode_t	*ip)
1654{
1655	xfs_mount_t	*mp = ip->i_mount;
1656	int		error;
1657
1658	if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1659		return 0;
1660
1661	/* If this is a read-only mount, don't do this (would generate I/O) */
1662	if (mp->m_flags & XFS_MOUNT_RDONLY)
1663		return 0;
1664
1665	if (!XFS_FORCED_SHUTDOWN(mp)) {
1666		int truncated;
1667
1668		/*
 
 
 
 
 
 
 
 
 
 
1669		 * If we previously truncated this file and removed old data
1670		 * in the process, we want to initiate "early" writeout on
1671		 * the last close.  This is an attempt to combat the notorious
1672		 * NULL files problem which is particularly noticeable from a
1673		 * truncate down, buffered (re-)write (delalloc), followed by
1674		 * a crash.  What we are effectively doing here is
1675		 * significantly reducing the time window where we'd otherwise
1676		 * be exposed to that problem.
1677		 */
1678		truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1679		if (truncated) {
1680			xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1681			if (ip->i_delayed_blks > 0) {
1682				error = filemap_flush(VFS_I(ip)->i_mapping);
1683				if (error)
1684					return error;
1685			}
1686		}
1687	}
1688
1689	if (VFS_I(ip)->i_nlink == 0)
1690		return 0;
1691
1692	if (xfs_can_free_eofblocks(ip, false)) {
1693
1694		/*
1695		 * Check if the inode is being opened, written and closed
1696		 * frequently and we have delayed allocation blocks outstanding
1697		 * (e.g. streaming writes from the NFS server), truncating the
1698		 * blocks past EOF will cause fragmentation to occur.
1699		 *
1700		 * In this case don't do the truncation, but we have to be
1701		 * careful how we detect this case. Blocks beyond EOF show up as
1702		 * i_delayed_blks even when the inode is clean, so we need to
1703		 * truncate them away first before checking for a dirty release.
1704		 * Hence on the first dirty close we will still remove the
1705		 * speculative allocation, but after that we will leave it in
1706		 * place.
1707		 */
1708		if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1709			return 0;
1710		/*
1711		 * If we can't get the iolock just skip truncating the blocks
1712		 * past EOF because we could deadlock with the mmap_sem
1713		 * otherwise. We'll get another chance to drop them once the
1714		 * last reference to the inode is dropped, so we'll never leak
1715		 * blocks permanently.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1716		 */
1717		if (xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1718			error = xfs_free_eofblocks(ip);
1719			xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1720			if (error)
1721				return error;
1722		}
1723
1724		/* delalloc blocks after truncation means it really is dirty */
1725		if (ip->i_delayed_blks)
1726			xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1727	}
1728	return 0;
1729}
1730
1731/*
1732 * xfs_inactive_truncate
1733 *
1734 * Called to perform a truncate when an inode becomes unlinked.
1735 */
1736STATIC int
1737xfs_inactive_truncate(
1738	struct xfs_inode *ip)
1739{
1740	struct xfs_mount	*mp = ip->i_mount;
1741	struct xfs_trans	*tp;
1742	int			error;
1743
1744	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
 
1745	if (error) {
1746		ASSERT(XFS_FORCED_SHUTDOWN(mp));
 
1747		return error;
1748	}
1749
1750	xfs_ilock(ip, XFS_ILOCK_EXCL);
1751	xfs_trans_ijoin(tp, ip, 0);
1752
1753	/*
1754	 * Log the inode size first to prevent stale data exposure in the event
1755	 * of a system crash before the truncate completes. See the related
1756	 * comment in xfs_vn_setattr_size() for details.
1757	 */
1758	ip->i_d.di_size = 0;
1759	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1760
1761	error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1762	if (error)
1763		goto error_trans_cancel;
1764
1765	ASSERT(ip->i_d.di_nextents == 0);
1766
1767	error = xfs_trans_commit(tp);
1768	if (error)
1769		goto error_unlock;
1770
1771	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1772	return 0;
1773
1774error_trans_cancel:
1775	xfs_trans_cancel(tp);
1776error_unlock:
1777	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1778	return error;
1779}
1780
1781/*
1782 * xfs_inactive_ifree()
1783 *
1784 * Perform the inode free when an inode is unlinked.
1785 */
1786STATIC int
1787xfs_inactive_ifree(
1788	struct xfs_inode *ip)
1789{
1790	struct xfs_defer_ops	dfops;
1791	xfs_fsblock_t		first_block;
 
1792	struct xfs_mount	*mp = ip->i_mount;
1793	struct xfs_trans	*tp;
1794	int			error;
1795
1796	/*
1797	 * We try to use a per-AG reservation for any block needed by the finobt
1798	 * tree, but as the finobt feature predates the per-AG reservation
1799	 * support a degraded file system might not have enough space for the
1800	 * reservation at mount time.  In that case try to dip into the reserved
1801	 * pool and pray.
1802	 *
1803	 * Send a warning if the reservation does happen to fail, as the inode
1804	 * now remains allocated and sits on the unlinked list until the fs is
1805	 * repaired.
1806	 */
1807	if (unlikely(mp->m_inotbt_nores)) {
1808		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1809				XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1810				&tp);
1811	} else {
1812		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1813	}
1814	if (error) {
1815		if (error == -ENOSPC) {
1816			xfs_warn_ratelimited(mp,
1817			"Failed to remove inode(s) from unlinked list. "
1818			"Please free space, unmount and run xfs_repair.");
1819		} else {
1820			ASSERT(XFS_FORCED_SHUTDOWN(mp));
1821		}
1822		return error;
1823	}
1824
1825	xfs_ilock(ip, XFS_ILOCK_EXCL);
1826	xfs_trans_ijoin(tp, ip, 0);
1827
1828	xfs_defer_init(&dfops, &first_block);
1829	error = xfs_ifree(tp, ip, &dfops);
1830	if (error) {
1831		/*
1832		 * If we fail to free the inode, shut down.  The cancel
1833		 * might do that, we need to make sure.  Otherwise the
1834		 * inode might be lost for a long time or forever.
1835		 */
1836		if (!XFS_FORCED_SHUTDOWN(mp)) {
1837			xfs_notice(mp, "%s: xfs_ifree returned error %d",
1838				__func__, error);
1839			xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1840		}
1841		xfs_trans_cancel(tp);
1842		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1843		return error;
1844	}
1845
1846	/*
1847	 * Credit the quota account(s). The inode is gone.
1848	 */
1849	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1850
1851	/*
1852	 * Just ignore errors at this point.  There is nothing we can do except
1853	 * to try to keep going. Make sure it's not a silent error.
 
1854	 */
1855	error = xfs_defer_finish(&tp, &dfops, NULL);
1856	if (error) {
1857		xfs_notice(mp, "%s: xfs_defer_finish returned error %d",
1858			__func__, error);
1859		xfs_defer_cancel(&dfops);
1860	}
1861	error = xfs_trans_commit(tp);
1862	if (error)
1863		xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1864			__func__, error);
1865
1866	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1867	return 0;
1868}
1869
1870/*
1871 * xfs_inactive
1872 *
1873 * This is called when the vnode reference count for the vnode
1874 * goes to zero.  If the file has been unlinked, then it must
1875 * now be truncated.  Also, we clear all of the read-ahead state
1876 * kept for the inode here since the file is now closed.
1877 */
1878void
1879xfs_inactive(
1880	xfs_inode_t	*ip)
1881{
1882	struct xfs_mount	*mp;
1883	int			error;
1884	int			truncate = 0;
1885
1886	/*
1887	 * If the inode is already free, then there can be nothing
1888	 * to clean up here.
1889	 */
1890	if (VFS_I(ip)->i_mode == 0) {
1891		ASSERT(ip->i_df.if_real_bytes == 0);
1892		ASSERT(ip->i_df.if_broot_bytes == 0);
1893		return;
1894	}
1895
1896	mp = ip->i_mount;
1897	ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1898
1899	/* If this is a read-only mount, don't do this (would generate I/O) */
1900	if (mp->m_flags & XFS_MOUNT_RDONLY)
1901		return;
1902
1903	if (VFS_I(ip)->i_nlink != 0) {
1904		/*
1905		 * force is true because we are evicting an inode from the
1906		 * cache. Post-eof blocks must be freed, lest we end up with
1907		 * broken free space accounting.
1908		 */
1909		if (xfs_can_free_eofblocks(ip, true)) {
1910			xfs_ilock(ip, XFS_IOLOCK_EXCL);
1911			xfs_free_eofblocks(ip);
1912			xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1913		}
1914
1915		return;
1916	}
1917
1918	if (S_ISREG(VFS_I(ip)->i_mode) &&
1919	    (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1920	     ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1921		truncate = 1;
1922
1923	error = xfs_qm_dqattach(ip, 0);
1924	if (error)
1925		return;
1926
1927	if (S_ISLNK(VFS_I(ip)->i_mode))
1928		error = xfs_inactive_symlink(ip);
1929	else if (truncate)
1930		error = xfs_inactive_truncate(ip);
1931	if (error)
1932		return;
1933
1934	/*
1935	 * If there are attributes associated with the file then blow them away
1936	 * now.  The code calls a routine that recursively deconstructs the
1937	 * attribute fork. If also blows away the in-core attribute fork.
 
1938	 */
1939	if (XFS_IFORK_Q(ip)) {
 
 
1940		error = xfs_attr_inactive(ip);
1941		if (error)
1942			return;
1943	}
1944
1945	ASSERT(!ip->i_afp);
 
 
1946	ASSERT(ip->i_d.di_anextents == 0);
1947	ASSERT(ip->i_d.di_forkoff == 0);
1948
1949	/*
1950	 * Free the inode.
1951	 */
1952	error = xfs_inactive_ifree(ip);
1953	if (error)
1954		return;
1955
1956	/*
1957	 * Release the dquots held by inode, if any.
1958	 */
1959	xfs_qm_dqdetach(ip);
1960}
1961
1962/*
1963 * This is called when the inode's link count goes to 0 or we are creating a
1964 * tmpfile via O_TMPFILE. In the case of a tmpfile, @ignore_linkcount will be
1965 * set to true as the link count is dropped to zero by the VFS after we've
1966 * created the file successfully, so we have to add it to the unlinked list
1967 * while the link count is non-zero.
1968 *
1969 * We place the on-disk inode on a list in the AGI.  It will be pulled from this
1970 * list when the inode is freed.
1971 */
1972STATIC int
1973xfs_iunlink(
1974	struct xfs_trans *tp,
1975	struct xfs_inode *ip)
1976{
1977	xfs_mount_t	*mp = tp->t_mountp;
1978	xfs_agi_t	*agi;
1979	xfs_dinode_t	*dip;
1980	xfs_buf_t	*agibp;
1981	xfs_buf_t	*ibp;
1982	xfs_agino_t	agino;
1983	short		bucket_index;
1984	int		offset;
1985	int		error;
1986
1987	ASSERT(VFS_I(ip)->i_mode != 0);
 
 
 
1988
1989	/*
1990	 * Get the agi buffer first.  It ensures lock ordering
1991	 * on the list.
1992	 */
1993	error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
1994	if (error)
1995		return error;
1996	agi = XFS_BUF_TO_AGI(agibp);
1997
1998	/*
1999	 * Get the index into the agi hash table for the
2000	 * list this inode will go on.
2001	 */
2002	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2003	ASSERT(agino != 0);
2004	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2005	ASSERT(agi->agi_unlinked[bucket_index]);
2006	ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
2007
2008	if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
2009		/*
2010		 * There is already another inode in the bucket we need
2011		 * to add ourselves to.  Add us at the front of the list.
2012		 * Here we put the head pointer into our next pointer,
2013		 * and then we fall through to point the head at us.
2014		 */
2015		error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2016				       0, 0);
2017		if (error)
2018			return error;
2019
2020		ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
2021		dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
2022		offset = ip->i_imap.im_boffset +
2023			offsetof(xfs_dinode_t, di_next_unlinked);
2024
2025		/* need to recalc the inode CRC if appropriate */
2026		xfs_dinode_calc_crc(mp, dip);
2027
2028		xfs_trans_inode_buf(tp, ibp);
2029		xfs_trans_log_buf(tp, ibp, offset,
2030				  (offset + sizeof(xfs_agino_t) - 1));
2031		xfs_inobp_check(mp, ibp);
2032	}
2033
2034	/*
2035	 * Point the bucket head pointer at the inode being inserted.
2036	 */
2037	ASSERT(agino != 0);
2038	agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
2039	offset = offsetof(xfs_agi_t, agi_unlinked) +
2040		(sizeof(xfs_agino_t) * bucket_index);
2041	xfs_trans_log_buf(tp, agibp, offset,
2042			  (offset + sizeof(xfs_agino_t) - 1));
2043	return 0;
2044}
2045
2046/*
2047 * Pull the on-disk inode from the AGI unlinked list.
2048 */
2049STATIC int
2050xfs_iunlink_remove(
2051	xfs_trans_t	*tp,
2052	xfs_inode_t	*ip)
2053{
2054	xfs_ino_t	next_ino;
2055	xfs_mount_t	*mp;
2056	xfs_agi_t	*agi;
2057	xfs_dinode_t	*dip;
2058	xfs_buf_t	*agibp;
2059	xfs_buf_t	*ibp;
2060	xfs_agnumber_t	agno;
2061	xfs_agino_t	agino;
2062	xfs_agino_t	next_agino;
2063	xfs_buf_t	*last_ibp;
2064	xfs_dinode_t	*last_dip = NULL;
2065	short		bucket_index;
2066	int		offset, last_offset = 0;
2067	int		error;
2068
2069	mp = tp->t_mountp;
2070	agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2071
2072	/*
2073	 * Get the agi buffer first.  It ensures lock ordering
2074	 * on the list.
2075	 */
2076	error = xfs_read_agi(mp, tp, agno, &agibp);
2077	if (error)
2078		return error;
2079
2080	agi = XFS_BUF_TO_AGI(agibp);
2081
2082	/*
2083	 * Get the index into the agi hash table for the
2084	 * list this inode will go on.
2085	 */
2086	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2087	ASSERT(agino != 0);
2088	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2089	ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
2090	ASSERT(agi->agi_unlinked[bucket_index]);
2091
2092	if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
2093		/*
2094		 * We're at the head of the list.  Get the inode's on-disk
2095		 * buffer to see if there is anyone after us on the list.
2096		 * Only modify our next pointer if it is not already NULLAGINO.
2097		 * This saves us the overhead of dealing with the buffer when
2098		 * there is no need to change it.
2099		 */
2100		error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2101				       0, 0);
2102		if (error) {
2103			xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2104				__func__, error);
2105			return error;
2106		}
2107		next_agino = be32_to_cpu(dip->di_next_unlinked);
2108		ASSERT(next_agino != 0);
2109		if (next_agino != NULLAGINO) {
2110			dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2111			offset = ip->i_imap.im_boffset +
2112				offsetof(xfs_dinode_t, di_next_unlinked);
2113
2114			/* need to recalc the inode CRC if appropriate */
2115			xfs_dinode_calc_crc(mp, dip);
2116
2117			xfs_trans_inode_buf(tp, ibp);
2118			xfs_trans_log_buf(tp, ibp, offset,
2119					  (offset + sizeof(xfs_agino_t) - 1));
2120			xfs_inobp_check(mp, ibp);
2121		} else {
2122			xfs_trans_brelse(tp, ibp);
2123		}
2124		/*
2125		 * Point the bucket head pointer at the next inode.
2126		 */
2127		ASSERT(next_agino != 0);
2128		ASSERT(next_agino != agino);
2129		agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
2130		offset = offsetof(xfs_agi_t, agi_unlinked) +
2131			(sizeof(xfs_agino_t) * bucket_index);
2132		xfs_trans_log_buf(tp, agibp, offset,
2133				  (offset + sizeof(xfs_agino_t) - 1));
2134	} else {
2135		/*
2136		 * We need to search the list for the inode being freed.
2137		 */
2138		next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2139		last_ibp = NULL;
2140		while (next_agino != agino) {
2141			struct xfs_imap	imap;
2142
2143			if (last_ibp)
2144				xfs_trans_brelse(tp, last_ibp);
2145
2146			imap.im_blkno = 0;
2147			next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
2148
2149			error = xfs_imap(mp, tp, next_ino, &imap, 0);
2150			if (error) {
2151				xfs_warn(mp,
2152	"%s: xfs_imap returned error %d.",
2153					 __func__, error);
2154				return error;
2155			}
2156
2157			error = xfs_imap_to_bp(mp, tp, &imap, &last_dip,
2158					       &last_ibp, 0, 0);
2159			if (error) {
2160				xfs_warn(mp,
2161	"%s: xfs_imap_to_bp returned error %d.",
2162					__func__, error);
2163				return error;
2164			}
2165
2166			last_offset = imap.im_boffset;
2167			next_agino = be32_to_cpu(last_dip->di_next_unlinked);
2168			ASSERT(next_agino != NULLAGINO);
2169			ASSERT(next_agino != 0);
2170		}
2171
2172		/*
2173		 * Now last_ibp points to the buffer previous to us on the
2174		 * unlinked list.  Pull us from the list.
2175		 */
2176		error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2177				       0, 0);
2178		if (error) {
2179			xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
2180				__func__, error);
2181			return error;
2182		}
2183		next_agino = be32_to_cpu(dip->di_next_unlinked);
2184		ASSERT(next_agino != 0);
2185		ASSERT(next_agino != agino);
2186		if (next_agino != NULLAGINO) {
2187			dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2188			offset = ip->i_imap.im_boffset +
2189				offsetof(xfs_dinode_t, di_next_unlinked);
2190
2191			/* need to recalc the inode CRC if appropriate */
2192			xfs_dinode_calc_crc(mp, dip);
2193
2194			xfs_trans_inode_buf(tp, ibp);
2195			xfs_trans_log_buf(tp, ibp, offset,
2196					  (offset + sizeof(xfs_agino_t) - 1));
2197			xfs_inobp_check(mp, ibp);
2198		} else {
2199			xfs_trans_brelse(tp, ibp);
2200		}
2201		/*
2202		 * Point the previous inode on the list to the next inode.
2203		 */
2204		last_dip->di_next_unlinked = cpu_to_be32(next_agino);
2205		ASSERT(next_agino != 0);
2206		offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
2207
2208		/* need to recalc the inode CRC if appropriate */
2209		xfs_dinode_calc_crc(mp, last_dip);
2210
2211		xfs_trans_inode_buf(tp, last_ibp);
2212		xfs_trans_log_buf(tp, last_ibp, offset,
2213				  (offset + sizeof(xfs_agino_t) - 1));
2214		xfs_inobp_check(mp, last_ibp);
2215	}
2216	return 0;
2217}
2218
2219/*
2220 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2221 * inodes that are in memory - they all must be marked stale and attached to
2222 * the cluster buffer.
2223 */
2224STATIC int
2225xfs_ifree_cluster(
2226	xfs_inode_t		*free_ip,
2227	xfs_trans_t		*tp,
2228	struct xfs_icluster	*xic)
2229{
2230	xfs_mount_t		*mp = free_ip->i_mount;
2231	int			blks_per_cluster;
2232	int			inodes_per_cluster;
2233	int			nbufs;
2234	int			i, j;
2235	int			ioffset;
2236	xfs_daddr_t		blkno;
2237	xfs_buf_t		*bp;
2238	xfs_inode_t		*ip;
2239	xfs_inode_log_item_t	*iip;
2240	xfs_log_item_t		*lip;
2241	struct xfs_perag	*pag;
2242	xfs_ino_t		inum;
2243
2244	inum = xic->first_ino;
2245	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2246	blks_per_cluster = xfs_icluster_size_fsb(mp);
2247	inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
2248	nbufs = mp->m_ialloc_blks / blks_per_cluster;
2249
2250	for (j = 0; j < nbufs; j++, inum += inodes_per_cluster) {
2251		/*
2252		 * The allocation bitmap tells us which inodes of the chunk were
2253		 * physically allocated. Skip the cluster if an inode falls into
2254		 * a sparse region.
2255		 */
2256		ioffset = inum - xic->first_ino;
2257		if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2258			ASSERT(do_mod(ioffset, inodes_per_cluster) == 0);
2259			continue;
2260		}
2261
2262		blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2263					 XFS_INO_TO_AGBNO(mp, inum));
2264
2265		/*
2266		 * We obtain and lock the backing buffer first in the process
2267		 * here, as we have to ensure that any dirty inode that we
2268		 * can't get the flush lock on is attached to the buffer.
2269		 * If we scan the in-memory inodes first, then buffer IO can
2270		 * complete before we get a lock on it, and hence we may fail
2271		 * to mark all the active inodes on the buffer stale.
2272		 */
2273		bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2274					mp->m_bsize * blks_per_cluster,
2275					XBF_UNMAPPED);
2276
2277		if (!bp)
2278			return -ENOMEM;
2279
2280		/*
2281		 * This buffer may not have been correctly initialised as we
2282		 * didn't read it from disk. That's not important because we are
2283		 * only using to mark the buffer as stale in the log, and to
2284		 * attach stale cached inodes on it. That means it will never be
2285		 * dispatched for IO. If it is, we want to know about it, and we
2286		 * want it to fail. We can acheive this by adding a write
2287		 * verifier to the buffer.
2288		 */
2289		 bp->b_ops = &xfs_inode_buf_ops;
2290
2291		/*
2292		 * Walk the inodes already attached to the buffer and mark them
2293		 * stale. These will all have the flush locks held, so an
2294		 * in-memory inode walk can't lock them. By marking them all
2295		 * stale first, we will not attempt to lock them in the loop
2296		 * below as the XFS_ISTALE flag will be set.
2297		 */
2298		lip = bp->b_fspriv;
2299		while (lip) {
2300			if (lip->li_type == XFS_LI_INODE) {
2301				iip = (xfs_inode_log_item_t *)lip;
2302				ASSERT(iip->ili_logged == 1);
2303				lip->li_cb = xfs_istale_done;
2304				xfs_trans_ail_copy_lsn(mp->m_ail,
2305							&iip->ili_flush_lsn,
2306							&iip->ili_item.li_lsn);
2307				xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2308			}
2309			lip = lip->li_bio_list;
2310		}
2311
2312
2313		/*
2314		 * For each inode in memory attempt to add it to the inode
2315		 * buffer and set it up for being staled on buffer IO
2316		 * completion.  This is safe as we've locked out tail pushing
2317		 * and flushing by locking the buffer.
2318		 *
2319		 * We have already marked every inode that was part of a
2320		 * transaction stale above, which means there is no point in
2321		 * even trying to lock them.
2322		 */
2323		for (i = 0; i < inodes_per_cluster; i++) {
2324retry:
2325			rcu_read_lock();
2326			ip = radix_tree_lookup(&pag->pag_ici_root,
2327					XFS_INO_TO_AGINO(mp, (inum + i)));
2328
2329			/* Inode not in memory, nothing to do */
2330			if (!ip) {
2331				rcu_read_unlock();
2332				continue;
2333			}
2334
2335			/*
2336			 * because this is an RCU protected lookup, we could
2337			 * find a recently freed or even reallocated inode
2338			 * during the lookup. We need to check under the
2339			 * i_flags_lock for a valid inode here. Skip it if it
2340			 * is not valid, the wrong inode or stale.
2341			 */
2342			spin_lock(&ip->i_flags_lock);
2343			if (ip->i_ino != inum + i ||
2344			    __xfs_iflags_test(ip, XFS_ISTALE)) {
2345				spin_unlock(&ip->i_flags_lock);
2346				rcu_read_unlock();
2347				continue;
2348			}
2349			spin_unlock(&ip->i_flags_lock);
2350
2351			/*
2352			 * Don't try to lock/unlock the current inode, but we
2353			 * _cannot_ skip the other inodes that we did not find
2354			 * in the list attached to the buffer and are not
2355			 * already marked stale. If we can't lock it, back off
2356			 * and retry.
2357			 */
2358			if (ip != free_ip &&
2359			    !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2360				rcu_read_unlock();
2361				delay(1);
2362				goto retry;
2363			}
2364			rcu_read_unlock();
2365
2366			xfs_iflock(ip);
2367			xfs_iflags_set(ip, XFS_ISTALE);
2368
2369			/*
2370			 * we don't need to attach clean inodes or those only
2371			 * with unlogged changes (which we throw away, anyway).
2372			 */
2373			iip = ip->i_itemp;
2374			if (!iip || xfs_inode_clean(ip)) {
2375				ASSERT(ip != free_ip);
2376				xfs_ifunlock(ip);
2377				xfs_iunlock(ip, XFS_ILOCK_EXCL);
2378				continue;
2379			}
2380
2381			iip->ili_last_fields = iip->ili_fields;
2382			iip->ili_fields = 0;
2383			iip->ili_fsync_fields = 0;
2384			iip->ili_logged = 1;
2385			xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2386						&iip->ili_item.li_lsn);
2387
2388			xfs_buf_attach_iodone(bp, xfs_istale_done,
2389						  &iip->ili_item);
2390
2391			if (ip != free_ip)
2392				xfs_iunlock(ip, XFS_ILOCK_EXCL);
2393		}
2394
2395		xfs_trans_stale_inode_buf(tp, bp);
2396		xfs_trans_binval(tp, bp);
2397	}
2398
2399	xfs_perag_put(pag);
2400	return 0;
2401}
2402
2403/*
2404 * This is called to return an inode to the inode free list.
2405 * The inode should already be truncated to 0 length and have
2406 * no pages associated with it.  This routine also assumes that
2407 * the inode is already a part of the transaction.
2408 *
2409 * The on-disk copy of the inode will have been added to the list
2410 * of unlinked inodes in the AGI. We need to remove the inode from
2411 * that list atomically with respect to freeing it here.
2412 */
2413int
2414xfs_ifree(
2415	xfs_trans_t	*tp,
2416	xfs_inode_t	*ip,
2417	struct xfs_defer_ops	*dfops)
2418{
2419	int			error;
2420	struct xfs_icluster	xic = { 0 };
 
2421
2422	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2423	ASSERT(VFS_I(ip)->i_nlink == 0);
2424	ASSERT(ip->i_d.di_nextents == 0);
2425	ASSERT(ip->i_d.di_anextents == 0);
2426	ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2427	ASSERT(ip->i_d.di_nblocks == 0);
2428
2429	/*
2430	 * Pull the on-disk inode from the AGI unlinked list.
2431	 */
2432	error = xfs_iunlink_remove(tp, ip);
2433	if (error)
2434		return error;
2435
2436	error = xfs_difree(tp, ip->i_ino, dfops, &xic);
2437	if (error)
2438		return error;
2439
2440	VFS_I(ip)->i_mode = 0;		/* mark incore inode as free */
2441	ip->i_d.di_flags = 0;
2442	ip->i_d.di_dmevmask = 0;
2443	ip->i_d.di_forkoff = 0;		/* mark the attr fork not in use */
2444	ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2445	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2446	/*
2447	 * Bump the generation count so no one will be confused
2448	 * by reincarnations of this inode.
2449	 */
2450	VFS_I(ip)->i_generation++;
2451	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2452
2453	if (xic.deleted)
2454		error = xfs_ifree_cluster(ip, tp, &xic);
2455
2456	return error;
2457}
2458
2459/*
2460 * This is called to unpin an inode.  The caller must have the inode locked
2461 * in at least shared mode so that the buffer cannot be subsequently pinned
2462 * once someone is waiting for it to be unpinned.
2463 */
2464static void
2465xfs_iunpin(
2466	struct xfs_inode	*ip)
2467{
2468	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2469
2470	trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2471
2472	/* Give the log a push to start the unpinning I/O */
2473	xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0);
2474
2475}
2476
2477static void
2478__xfs_iunpin_wait(
2479	struct xfs_inode	*ip)
2480{
2481	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2482	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2483
2484	xfs_iunpin(ip);
2485
2486	do {
2487		prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
2488		if (xfs_ipincount(ip))
2489			io_schedule();
2490	} while (xfs_ipincount(ip));
2491	finish_wait(wq, &wait.wait);
2492}
2493
2494void
2495xfs_iunpin_wait(
2496	struct xfs_inode	*ip)
2497{
2498	if (xfs_ipincount(ip))
2499		__xfs_iunpin_wait(ip);
2500}
2501
2502/*
2503 * Removing an inode from the namespace involves removing the directory entry
2504 * and dropping the link count on the inode. Removing the directory entry can
2505 * result in locking an AGF (directory blocks were freed) and removing a link
2506 * count can result in placing the inode on an unlinked list which results in
2507 * locking an AGI.
2508 *
2509 * The big problem here is that we have an ordering constraint on AGF and AGI
2510 * locking - inode allocation locks the AGI, then can allocate a new extent for
2511 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2512 * removes the inode from the unlinked list, requiring that we lock the AGI
2513 * first, and then freeing the inode can result in an inode chunk being freed
2514 * and hence freeing disk space requiring that we lock an AGF.
2515 *
2516 * Hence the ordering that is imposed by other parts of the code is AGI before
2517 * AGF. This means we cannot remove the directory entry before we drop the inode
2518 * reference count and put it on the unlinked list as this results in a lock
2519 * order of AGF then AGI, and this can deadlock against inode allocation and
2520 * freeing. Therefore we must drop the link counts before we remove the
2521 * directory entry.
2522 *
2523 * This is still safe from a transactional point of view - it is not until we
2524 * get to xfs_defer_finish() that we have the possibility of multiple
2525 * transactions in this operation. Hence as long as we remove the directory
2526 * entry and drop the link count in the first transaction of the remove
2527 * operation, there are no transactional constraints on the ordering here.
2528 */
2529int
2530xfs_remove(
2531	xfs_inode_t             *dp,
2532	struct xfs_name		*name,
2533	xfs_inode_t		*ip)
2534{
2535	xfs_mount_t		*mp = dp->i_mount;
2536	xfs_trans_t             *tp = NULL;
2537	int			is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2538	int                     error = 0;
2539	struct xfs_defer_ops	dfops;
2540	xfs_fsblock_t           first_block;
 
 
 
2541	uint			resblks;
 
2542
2543	trace_xfs_remove(dp, name);
2544
2545	if (XFS_FORCED_SHUTDOWN(mp))
2546		return -EIO;
2547
2548	error = xfs_qm_dqattach(dp, 0);
2549	if (error)
2550		goto std_return;
2551
2552	error = xfs_qm_dqattach(ip, 0);
2553	if (error)
2554		goto std_return;
2555
 
 
 
 
 
 
 
 
 
2556	/*
2557	 * We try to get the real space reservation first,
2558	 * allowing for directory btree deletion(s) implying
2559	 * possible bmap insert(s).  If we can't get the space
2560	 * reservation then we use 0 instead, and avoid the bmap
2561	 * btree insert(s) in the directory code by, if the bmap
2562	 * insert tries to happen, instead trimming the LAST
2563	 * block from the directory.
2564	 */
2565	resblks = XFS_REMOVE_SPACE_RES(mp);
2566	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2567	if (error == -ENOSPC) {
2568		resblks = 0;
2569		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2570				&tp);
2571	}
2572	if (error) {
2573		ASSERT(error != -ENOSPC);
2574		goto std_return;
 
2575	}
2576
2577	xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
2578
2579	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2580	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2581
2582	/*
2583	 * If we're removing a directory perform some additional validation.
2584	 */
 
2585	if (is_dir) {
2586		ASSERT(VFS_I(ip)->i_nlink >= 2);
2587		if (VFS_I(ip)->i_nlink != 2) {
2588			error = -ENOTEMPTY;
2589			goto out_trans_cancel;
2590		}
2591		if (!xfs_dir_isempty(ip)) {
2592			error = -ENOTEMPTY;
2593			goto out_trans_cancel;
2594		}
2595
2596		/* Drop the link from ip's "..".  */
2597		error = xfs_droplink(tp, dp);
2598		if (error)
2599			goto out_trans_cancel;
2600
2601		/* Drop the "." link from ip to self.  */
2602		error = xfs_droplink(tp, ip);
2603		if (error)
2604			goto out_trans_cancel;
2605	} else {
2606		/*
2607		 * When removing a non-directory we need to log the parent
2608		 * inode here.  For a directory this is done implicitly
2609		 * by the xfs_droplink call for the ".." entry.
2610		 */
2611		xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2612	}
2613	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2614
2615	/* Drop the link from dp to ip. */
2616	error = xfs_droplink(tp, ip);
2617	if (error)
2618		goto out_trans_cancel;
2619
2620	xfs_defer_init(&dfops, &first_block);
 
 
 
2621	error = xfs_dir_removename(tp, dp, name, ip->i_ino,
2622					&first_block, &dfops, resblks);
2623	if (error) {
2624		ASSERT(error != -ENOENT);
2625		goto out_bmap_cancel;
2626	}
2627
2628	/*
2629	 * If this is a synchronous mount, make sure that the
2630	 * remove transaction goes to disk before returning to
2631	 * the user.
2632	 */
2633	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2634		xfs_trans_set_sync(tp);
2635
2636	error = xfs_defer_finish(&tp, &dfops, NULL);
2637	if (error)
2638		goto out_bmap_cancel;
2639
2640	error = xfs_trans_commit(tp);
2641	if (error)
2642		goto std_return;
2643
2644	if (is_dir && xfs_inode_is_filestream(ip))
 
 
 
 
 
 
2645		xfs_filestream_deassociate(ip);
2646
2647	return 0;
2648
2649 out_bmap_cancel:
2650	xfs_defer_cancel(&dfops);
2651 out_trans_cancel:
2652	xfs_trans_cancel(tp);
2653 std_return:
2654	return error;
2655}
2656
2657/*
2658 * Enter all inodes for a rename transaction into a sorted array.
2659 */
2660#define __XFS_SORT_INODES	5
2661STATIC void
2662xfs_sort_for_rename(
2663	struct xfs_inode	*dp1,	/* in: old (source) directory inode */
2664	struct xfs_inode	*dp2,	/* in: new (target) directory inode */
2665	struct xfs_inode	*ip1,	/* in: inode of old entry */
2666	struct xfs_inode	*ip2,	/* in: inode of new entry */
2667	struct xfs_inode	*wip,	/* in: whiteout inode */
2668	struct xfs_inode	**i_tab,/* out: sorted array of inodes */
2669	int			*num_inodes)  /* in/out: inodes in array */
2670{
 
2671	int			i, j;
2672
2673	ASSERT(*num_inodes == __XFS_SORT_INODES);
2674	memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2675
2676	/*
2677	 * i_tab contains a list of pointers to inodes.  We initialize
2678	 * the table here & we'll sort it.  We will then use it to
2679	 * order the acquisition of the inode locks.
2680	 *
2681	 * Note that the table may contain duplicates.  e.g., dp1 == dp2.
2682	 */
2683	i = 0;
2684	i_tab[i++] = dp1;
2685	i_tab[i++] = dp2;
2686	i_tab[i++] = ip1;
2687	if (ip2)
2688		i_tab[i++] = ip2;
2689	if (wip)
2690		i_tab[i++] = wip;
2691	*num_inodes = i;
 
2692
2693	/*
2694	 * Sort the elements via bubble sort.  (Remember, there are at
2695	 * most 5 elements to sort, so this is adequate.)
2696	 */
2697	for (i = 0; i < *num_inodes; i++) {
2698		for (j = 1; j < *num_inodes; j++) {
2699			if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2700				struct xfs_inode *temp = i_tab[j];
2701				i_tab[j] = i_tab[j-1];
2702				i_tab[j-1] = temp;
2703			}
2704		}
2705	}
2706}
2707
2708static int
2709xfs_finish_rename(
2710	struct xfs_trans	*tp,
2711	struct xfs_defer_ops	*dfops)
2712{
2713	int			error;
2714
2715	/*
2716	 * If this is a synchronous mount, make sure that the rename transaction
2717	 * goes to disk before returning to the user.
2718	 */
2719	if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2720		xfs_trans_set_sync(tp);
2721
2722	error = xfs_defer_finish(&tp, dfops, NULL);
2723	if (error) {
2724		xfs_defer_cancel(dfops);
2725		xfs_trans_cancel(tp);
2726		return error;
2727	}
2728
2729	return xfs_trans_commit(tp);
2730}
2731
2732/*
2733 * xfs_cross_rename()
2734 *
2735 * responsible for handling RENAME_EXCHANGE flag in renameat2() sytemcall
2736 */
2737STATIC int
2738xfs_cross_rename(
2739	struct xfs_trans	*tp,
2740	struct xfs_inode	*dp1,
2741	struct xfs_name		*name1,
2742	struct xfs_inode	*ip1,
2743	struct xfs_inode	*dp2,
2744	struct xfs_name		*name2,
2745	struct xfs_inode	*ip2,
2746	struct xfs_defer_ops	*dfops,
2747	xfs_fsblock_t		*first_block,
2748	int			spaceres)
2749{
2750	int		error = 0;
2751	int		ip1_flags = 0;
2752	int		ip2_flags = 0;
2753	int		dp2_flags = 0;
2754
2755	/* Swap inode number for dirent in first parent */
2756	error = xfs_dir_replace(tp, dp1, name1,
2757				ip2->i_ino,
2758				first_block, dfops, spaceres);
2759	if (error)
2760		goto out_trans_abort;
2761
2762	/* Swap inode number for dirent in second parent */
2763	error = xfs_dir_replace(tp, dp2, name2,
2764				ip1->i_ino,
2765				first_block, dfops, spaceres);
2766	if (error)
2767		goto out_trans_abort;
2768
2769	/*
2770	 * If we're renaming one or more directories across different parents,
2771	 * update the respective ".." entries (and link counts) to match the new
2772	 * parents.
2773	 */
2774	if (dp1 != dp2) {
2775		dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2776
2777		if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2778			error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2779						dp1->i_ino, first_block,
2780						dfops, spaceres);
2781			if (error)
2782				goto out_trans_abort;
2783
2784			/* transfer ip2 ".." reference to dp1 */
2785			if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2786				error = xfs_droplink(tp, dp2);
2787				if (error)
2788					goto out_trans_abort;
2789				error = xfs_bumplink(tp, dp1);
2790				if (error)
2791					goto out_trans_abort;
2792			}
2793
2794			/*
2795			 * Although ip1 isn't changed here, userspace needs
2796			 * to be warned about the change, so that applications
2797			 * relying on it (like backup ones), will properly
2798			 * notify the change
2799			 */
2800			ip1_flags |= XFS_ICHGTIME_CHG;
2801			ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2802		}
2803
2804		if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2805			error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2806						dp2->i_ino, first_block,
2807						dfops, spaceres);
2808			if (error)
2809				goto out_trans_abort;
2810
2811			/* transfer ip1 ".." reference to dp2 */
2812			if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2813				error = xfs_droplink(tp, dp1);
2814				if (error)
2815					goto out_trans_abort;
2816				error = xfs_bumplink(tp, dp2);
2817				if (error)
2818					goto out_trans_abort;
2819			}
2820
2821			/*
2822			 * Although ip2 isn't changed here, userspace needs
2823			 * to be warned about the change, so that applications
2824			 * relying on it (like backup ones), will properly
2825			 * notify the change
2826			 */
2827			ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2828			ip2_flags |= XFS_ICHGTIME_CHG;
2829		}
2830	}
2831
2832	if (ip1_flags) {
2833		xfs_trans_ichgtime(tp, ip1, ip1_flags);
2834		xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2835	}
2836	if (ip2_flags) {
2837		xfs_trans_ichgtime(tp, ip2, ip2_flags);
2838		xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2839	}
2840	if (dp2_flags) {
2841		xfs_trans_ichgtime(tp, dp2, dp2_flags);
2842		xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2843	}
2844	xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2845	xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2846	return xfs_finish_rename(tp, dfops);
2847
2848out_trans_abort:
2849	xfs_defer_cancel(dfops);
2850	xfs_trans_cancel(tp);
2851	return error;
2852}
2853
2854/*
2855 * xfs_rename_alloc_whiteout()
2856 *
2857 * Return a referenced, unlinked, unlocked inode that that can be used as a
2858 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
2859 * crash between allocating the inode and linking it into the rename transaction
2860 * recovery will free the inode and we won't leak it.
2861 */
2862static int
2863xfs_rename_alloc_whiteout(
2864	struct xfs_inode	*dp,
2865	struct xfs_inode	**wip)
2866{
2867	struct xfs_inode	*tmpfile;
2868	int			error;
2869
2870	error = xfs_create_tmpfile(dp, NULL, S_IFCHR | WHITEOUT_MODE, &tmpfile);
2871	if (error)
2872		return error;
2873
2874	/*
2875	 * Prepare the tmpfile inode as if it were created through the VFS.
2876	 * Otherwise, the link increment paths will complain about nlink 0->1.
2877	 * Drop the link count as done by d_tmpfile(), complete the inode setup
2878	 * and flag it as linkable.
2879	 */
2880	drop_nlink(VFS_I(tmpfile));
2881	xfs_setup_iops(tmpfile);
2882	xfs_finish_inode_setup(tmpfile);
2883	VFS_I(tmpfile)->i_state |= I_LINKABLE;
2884
2885	*wip = tmpfile;
2886	return 0;
2887}
2888
2889/*
2890 * xfs_rename
2891 */
2892int
2893xfs_rename(
2894	struct xfs_inode	*src_dp,
2895	struct xfs_name		*src_name,
2896	struct xfs_inode	*src_ip,
2897	struct xfs_inode	*target_dp,
2898	struct xfs_name		*target_name,
2899	struct xfs_inode	*target_ip,
2900	unsigned int		flags)
2901{
2902	struct xfs_mount	*mp = src_dp->i_mount;
2903	struct xfs_trans	*tp;
2904	struct xfs_defer_ops	dfops;
2905	xfs_fsblock_t		first_block;
2906	struct xfs_inode	*wip = NULL;		/* whiteout inode */
2907	struct xfs_inode	*inodes[__XFS_SORT_INODES];
2908	int			num_inodes = __XFS_SORT_INODES;
2909	bool			new_parent = (src_dp != target_dp);
2910	bool			src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
2911	int			spaceres;
2912	int			error;
2913
2914	trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2915
2916	if ((flags & RENAME_EXCHANGE) && !target_ip)
2917		return -EINVAL;
2918
2919	/*
2920	 * If we are doing a whiteout operation, allocate the whiteout inode
2921	 * we will be placing at the target and ensure the type is set
2922	 * appropriately.
2923	 */
2924	if (flags & RENAME_WHITEOUT) {
2925		ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
2926		error = xfs_rename_alloc_whiteout(target_dp, &wip);
2927		if (error)
2928			return error;
2929
2930		/* setup target dirent info as whiteout */
2931		src_name->type = XFS_DIR3_FT_CHRDEV;
2932	}
2933
2934	xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
2935				inodes, &num_inodes);
2936
 
 
 
2937	spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2938	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
2939	if (error == -ENOSPC) {
2940		spaceres = 0;
2941		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
2942				&tp);
 
 
 
2943	}
2944	if (error)
2945		goto out_release_wip;
2946
2947	/*
2948	 * Attach the dquots to the inodes
2949	 */
2950	error = xfs_qm_vop_rename_dqattach(inodes);
2951	if (error)
2952		goto out_trans_cancel;
 
 
2953
2954	/*
2955	 * Lock all the participating inodes. Depending upon whether
2956	 * the target_name exists in the target directory, and
2957	 * whether the target directory is the same as the source
2958	 * directory, we can lock from 2 to 4 inodes.
2959	 */
2960	xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2961
2962	/*
2963	 * Join all the inodes to the transaction. From this point on,
2964	 * we can rely on either trans_commit or trans_cancel to unlock
2965	 * them.
2966	 */
2967	xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2968	if (new_parent)
2969		xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2970	xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
2971	if (target_ip)
2972		xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
2973	if (wip)
2974		xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
2975
2976	/*
2977	 * If we are using project inheritance, we only allow renames
2978	 * into our tree when the project IDs are the same; else the
2979	 * tree quota mechanism would be circumvented.
2980	 */
2981	if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
2982		     (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
2983		error = -EXDEV;
2984		goto out_trans_cancel;
2985	}
2986
2987	xfs_defer_init(&dfops, &first_block);
2988
2989	/* RENAME_EXCHANGE is unique from here on. */
2990	if (flags & RENAME_EXCHANGE)
2991		return xfs_cross_rename(tp, src_dp, src_name, src_ip,
2992					target_dp, target_name, target_ip,
2993					&dfops, &first_block, spaceres);
2994
2995	/*
2996	 * Set up the target.
2997	 */
2998	if (target_ip == NULL) {
2999		/*
3000		 * If there's no space reservation, check the entry will
3001		 * fit before actually inserting it.
3002		 */
3003		if (!spaceres) {
3004			error = xfs_dir_canenter(tp, target_dp, target_name);
3005			if (error)
3006				goto out_trans_cancel;
3007		}
3008		/*
3009		 * If target does not exist and the rename crosses
3010		 * directories, adjust the target directory link count
3011		 * to account for the ".." reference from the new entry.
3012		 */
3013		error = xfs_dir_createname(tp, target_dp, target_name,
3014						src_ip->i_ino, &first_block,
3015						&dfops, spaceres);
 
 
3016		if (error)
3017			goto out_bmap_cancel;
3018
3019		xfs_trans_ichgtime(tp, target_dp,
3020					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3021
3022		if (new_parent && src_is_directory) {
3023			error = xfs_bumplink(tp, target_dp);
3024			if (error)
3025				goto out_bmap_cancel;
3026		}
3027	} else { /* target_ip != NULL */
3028		/*
3029		 * If target exists and it's a directory, check that both
3030		 * target and source are directories and that target can be
3031		 * destroyed, or that neither is a directory.
3032		 */
3033		if (S_ISDIR(VFS_I(target_ip)->i_mode)) {
3034			/*
3035			 * Make sure target dir is empty.
3036			 */
3037			if (!(xfs_dir_isempty(target_ip)) ||
3038			    (VFS_I(target_ip)->i_nlink > 2)) {
3039				error = -EEXIST;
3040				goto out_trans_cancel;
3041			}
3042		}
3043
3044		/*
3045		 * Link the source inode under the target name.
3046		 * If the source inode is a directory and we are moving
3047		 * it across directories, its ".." entry will be
3048		 * inconsistent until we replace that down below.
3049		 *
3050		 * In case there is already an entry with the same
3051		 * name at the destination directory, remove it first.
3052		 */
3053		error = xfs_dir_replace(tp, target_dp, target_name,
3054					src_ip->i_ino,
3055					&first_block, &dfops, spaceres);
3056		if (error)
3057			goto out_bmap_cancel;
3058
3059		xfs_trans_ichgtime(tp, target_dp,
3060					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3061
3062		/*
3063		 * Decrement the link count on the target since the target
3064		 * dir no longer points to it.
3065		 */
3066		error = xfs_droplink(tp, target_ip);
3067		if (error)
3068			goto out_bmap_cancel;
3069
3070		if (src_is_directory) {
3071			/*
3072			 * Drop the link from the old "." entry.
3073			 */
3074			error = xfs_droplink(tp, target_ip);
3075			if (error)
3076				goto out_bmap_cancel;
3077		}
3078	} /* target_ip != NULL */
3079
3080	/*
3081	 * Remove the source.
3082	 */
3083	if (new_parent && src_is_directory) {
3084		/*
3085		 * Rewrite the ".." entry to point to the new
3086		 * directory.
3087		 */
3088		error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3089					target_dp->i_ino,
3090					&first_block, &dfops, spaceres);
3091		ASSERT(error != -EEXIST);
3092		if (error)
3093			goto out_bmap_cancel;
3094	}
3095
3096	/*
3097	 * We always want to hit the ctime on the source inode.
3098	 *
3099	 * This isn't strictly required by the standards since the source
3100	 * inode isn't really being changed, but old unix file systems did
3101	 * it and some incremental backup programs won't work without it.
3102	 */
3103	xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3104	xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3105
3106	/*
3107	 * Adjust the link count on src_dp.  This is necessary when
3108	 * renaming a directory, either within one parent when
3109	 * the target existed, or across two parent directories.
3110	 */
3111	if (src_is_directory && (new_parent || target_ip != NULL)) {
3112
3113		/*
3114		 * Decrement link count on src_directory since the
3115		 * entry that's moved no longer points to it.
3116		 */
3117		error = xfs_droplink(tp, src_dp);
3118		if (error)
3119			goto out_bmap_cancel;
3120	}
3121
3122	/*
3123	 * For whiteouts, we only need to update the source dirent with the
3124	 * inode number of the whiteout inode rather than removing it
3125	 * altogether.
3126	 */
3127	if (wip) {
3128		error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3129					&first_block, &dfops, spaceres);
3130	} else
3131		error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3132					   &first_block, &dfops, spaceres);
3133	if (error)
3134		goto out_bmap_cancel;
3135
3136	/*
3137	 * For whiteouts, we need to bump the link count on the whiteout inode.
3138	 * This means that failures all the way up to this point leave the inode
3139	 * on the unlinked list and so cleanup is a simple matter of dropping
3140	 * the remaining reference to it. If we fail here after bumping the link
3141	 * count, we're shutting down the filesystem so we'll never see the
3142	 * intermediate state on disk.
3143	 */
3144	if (wip) {
3145		ASSERT(VFS_I(wip)->i_nlink == 0);
3146		error = xfs_bumplink(tp, wip);
3147		if (error)
3148			goto out_bmap_cancel;
3149		error = xfs_iunlink_remove(tp, wip);
3150		if (error)
3151			goto out_bmap_cancel;
3152		xfs_trans_log_inode(tp, wip, XFS_ILOG_CORE);
3153
3154		/*
3155		 * Now we have a real link, clear the "I'm a tmpfile" state
3156		 * flag from the inode so it doesn't accidentally get misused in
3157		 * future.
3158		 */
3159		VFS_I(wip)->i_state &= ~I_LINKABLE;
3160	}
3161
3162	xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3163	xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3164	if (new_parent)
3165		xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3166
3167	error = xfs_finish_rename(tp, &dfops);
3168	if (wip)
3169		IRELE(wip);
3170	return error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3171
3172out_bmap_cancel:
3173	xfs_defer_cancel(&dfops);
3174out_trans_cancel:
3175	xfs_trans_cancel(tp);
3176out_release_wip:
3177	if (wip)
3178		IRELE(wip);
3179	return error;
3180}
3181
3182STATIC int
3183xfs_iflush_cluster(
3184	struct xfs_inode	*ip,
3185	struct xfs_buf		*bp)
3186{
3187	struct xfs_mount	*mp = ip->i_mount;
3188	struct xfs_perag	*pag;
3189	unsigned long		first_index, mask;
3190	unsigned long		inodes_per_cluster;
3191	int			cilist_size;
3192	struct xfs_inode	**cilist;
3193	struct xfs_inode	*cip;
3194	int			nr_found;
3195	int			clcount = 0;
3196	int			bufwasdelwri;
3197	int			i;
3198
3199	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
3200
3201	inodes_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
3202	cilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
3203	cilist = kmem_alloc(cilist_size, KM_MAYFAIL|KM_NOFS);
3204	if (!cilist)
3205		goto out_put;
3206
3207	mask = ~(((mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog)) - 1);
3208	first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
3209	rcu_read_lock();
3210	/* really need a gang lookup range call here */
3211	nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)cilist,
3212					first_index, inodes_per_cluster);
3213	if (nr_found == 0)
3214		goto out_free;
3215
3216	for (i = 0; i < nr_found; i++) {
3217		cip = cilist[i];
3218		if (cip == ip)
3219			continue;
3220
3221		/*
3222		 * because this is an RCU protected lookup, we could find a
3223		 * recently freed or even reallocated inode during the lookup.
3224		 * We need to check under the i_flags_lock for a valid inode
3225		 * here. Skip it if it is not valid or the wrong inode.
3226		 */
3227		spin_lock(&cip->i_flags_lock);
3228		if (!cip->i_ino ||
3229		    __xfs_iflags_test(cip, XFS_ISTALE)) {
3230			spin_unlock(&cip->i_flags_lock);
3231			continue;
3232		}
3233
3234		/*
3235		 * Once we fall off the end of the cluster, no point checking
3236		 * any more inodes in the list because they will also all be
3237		 * outside the cluster.
3238		 */
3239		if ((XFS_INO_TO_AGINO(mp, cip->i_ino) & mask) != first_index) {
3240			spin_unlock(&cip->i_flags_lock);
3241			break;
3242		}
3243		spin_unlock(&cip->i_flags_lock);
3244
3245		/*
3246		 * Do an un-protected check to see if the inode is dirty and
3247		 * is a candidate for flushing.  These checks will be repeated
3248		 * later after the appropriate locks are acquired.
3249		 */
3250		if (xfs_inode_clean(cip) && xfs_ipincount(cip) == 0)
3251			continue;
3252
3253		/*
3254		 * Try to get locks.  If any are unavailable or it is pinned,
3255		 * then this inode cannot be flushed and is skipped.
3256		 */
3257
3258		if (!xfs_ilock_nowait(cip, XFS_ILOCK_SHARED))
3259			continue;
3260		if (!xfs_iflock_nowait(cip)) {
3261			xfs_iunlock(cip, XFS_ILOCK_SHARED);
3262			continue;
3263		}
3264		if (xfs_ipincount(cip)) {
3265			xfs_ifunlock(cip);
3266			xfs_iunlock(cip, XFS_ILOCK_SHARED);
3267			continue;
3268		}
3269
3270
3271		/*
3272		 * Check the inode number again, just to be certain we are not
3273		 * racing with freeing in xfs_reclaim_inode(). See the comments
3274		 * in that function for more information as to why the initial
3275		 * check is not sufficient.
3276		 */
3277		if (!cip->i_ino) {
3278			xfs_ifunlock(cip);
3279			xfs_iunlock(cip, XFS_ILOCK_SHARED);
3280			continue;
3281		}
3282
3283		/*
3284		 * arriving here means that this inode can be flushed.  First
3285		 * re-check that it's dirty before flushing.
3286		 */
3287		if (!xfs_inode_clean(cip)) {
3288			int	error;
3289			error = xfs_iflush_int(cip, bp);
3290			if (error) {
3291				xfs_iunlock(cip, XFS_ILOCK_SHARED);
3292				goto cluster_corrupt_out;
3293			}
3294			clcount++;
3295		} else {
3296			xfs_ifunlock(cip);
3297		}
3298		xfs_iunlock(cip, XFS_ILOCK_SHARED);
3299	}
3300
3301	if (clcount) {
3302		XFS_STATS_INC(mp, xs_icluster_flushcnt);
3303		XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3304	}
3305
3306out_free:
3307	rcu_read_unlock();
3308	kmem_free(cilist);
3309out_put:
3310	xfs_perag_put(pag);
3311	return 0;
3312
3313
3314cluster_corrupt_out:
3315	/*
3316	 * Corruption detected in the clustering loop.  Invalidate the
3317	 * inode buffer and shut down the filesystem.
3318	 */
3319	rcu_read_unlock();
3320	/*
3321	 * Clean up the buffer.  If it was delwri, just release it --
3322	 * brelse can handle it with no problems.  If not, shut down the
3323	 * filesystem before releasing the buffer.
3324	 */
3325	bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
3326	if (bufwasdelwri)
3327		xfs_buf_relse(bp);
3328
3329	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3330
3331	if (!bufwasdelwri) {
3332		/*
3333		 * Just like incore_relse: if we have b_iodone functions,
3334		 * mark the buffer as an error and call them.  Otherwise
3335		 * mark it as stale and brelse.
3336		 */
3337		if (bp->b_iodone) {
3338			bp->b_flags &= ~XBF_DONE;
3339			xfs_buf_stale(bp);
3340			xfs_buf_ioerror(bp, -EIO);
3341			xfs_buf_ioend(bp);
3342		} else {
3343			xfs_buf_stale(bp);
3344			xfs_buf_relse(bp);
3345		}
3346	}
3347
3348	/*
3349	 * Unlocks the flush lock
3350	 */
3351	xfs_iflush_abort(cip, false);
3352	kmem_free(cilist);
3353	xfs_perag_put(pag);
3354	return -EFSCORRUPTED;
3355}
3356
3357/*
3358 * Flush dirty inode metadata into the backing buffer.
3359 *
3360 * The caller must have the inode lock and the inode flush lock held.  The
3361 * inode lock will still be held upon return to the caller, and the inode
3362 * flush lock will be released after the inode has reached the disk.
3363 *
3364 * The caller must write out the buffer returned in *bpp and release it.
3365 */
3366int
3367xfs_iflush(
3368	struct xfs_inode	*ip,
3369	struct xfs_buf		**bpp)
3370{
3371	struct xfs_mount	*mp = ip->i_mount;
3372	struct xfs_buf		*bp = NULL;
3373	struct xfs_dinode	*dip;
3374	int			error;
3375
3376	XFS_STATS_INC(mp, xs_iflush_count);
3377
3378	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3379	ASSERT(xfs_isiflocked(ip));
3380	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3381	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3382
3383	*bpp = NULL;
3384
3385	xfs_iunpin_wait(ip);
3386
3387	/*
3388	 * For stale inodes we cannot rely on the backing buffer remaining
3389	 * stale in cache for the remaining life of the stale inode and so
3390	 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3391	 * inodes below. We have to check this after ensuring the inode is
3392	 * unpinned so that it is safe to reclaim the stale inode after the
3393	 * flush call.
3394	 */
3395	if (xfs_iflags_test(ip, XFS_ISTALE)) {
3396		xfs_ifunlock(ip);
3397		return 0;
3398	}
3399
3400	/*
3401	 * This may have been unpinned because the filesystem is shutting
3402	 * down forcibly. If that's the case we must not write this inode
3403	 * to disk, because the log record didn't make it to disk.
3404	 *
3405	 * We also have to remove the log item from the AIL in this case,
3406	 * as we wait for an empty AIL as part of the unmount process.
3407	 */
3408	if (XFS_FORCED_SHUTDOWN(mp)) {
3409		error = -EIO;
3410		goto abort_out;
3411	}
3412
3413	/*
3414	 * Get the buffer containing the on-disk inode. We are doing a try-lock
3415	 * operation here, so we may get  an EAGAIN error. In that case, we
3416	 * simply want to return with the inode still dirty.
3417	 *
3418	 * If we get any other error, we effectively have a corruption situation
3419	 * and we cannot flush the inode, so we treat it the same as failing
3420	 * xfs_iflush_int().
3421	 */
3422	error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3423			       0);
3424	if (error == -EAGAIN) {
3425		xfs_ifunlock(ip);
3426		return error;
3427	}
3428	if (error)
3429		goto corrupt_out;
3430
3431	/*
3432	 * First flush out the inode that xfs_iflush was called with.
3433	 */
3434	error = xfs_iflush_int(ip, bp);
3435	if (error)
3436		goto corrupt_out;
3437
3438	/*
3439	 * If the buffer is pinned then push on the log now so we won't
3440	 * get stuck waiting in the write for too long.
3441	 */
3442	if (xfs_buf_ispinned(bp))
3443		xfs_log_force(mp, 0);
3444
3445	/*
3446	 * inode clustering:
3447	 * see if other inodes can be gathered into this write
3448	 */
3449	error = xfs_iflush_cluster(ip, bp);
3450	if (error)
3451		goto cluster_corrupt_out;
3452
3453	*bpp = bp;
3454	return 0;
3455
3456corrupt_out:
3457	if (bp)
3458		xfs_buf_relse(bp);
3459	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3460cluster_corrupt_out:
3461	error = -EFSCORRUPTED;
3462abort_out:
3463	/*
3464	 * Unlocks the flush lock
3465	 */
3466	xfs_iflush_abort(ip, false);
3467	return error;
3468}
3469
3470STATIC int
3471xfs_iflush_int(
3472	struct xfs_inode	*ip,
3473	struct xfs_buf		*bp)
3474{
3475	struct xfs_inode_log_item *iip = ip->i_itemp;
3476	struct xfs_dinode	*dip;
3477	struct xfs_mount	*mp = ip->i_mount;
3478
3479	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3480	ASSERT(xfs_isiflocked(ip));
3481	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3482	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3483	ASSERT(iip != NULL && iip->ili_fields != 0);
3484	ASSERT(ip->i_d.di_version > 1);
3485
3486	/* set *dip = inode's place in the buffer */
3487	dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3488
3489	if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3490			       mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
3491		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3492			"%s: Bad inode %Lu magic number 0x%x, ptr 0x%p",
3493			__func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3494		goto corrupt_out;
3495	}
3496	if (S_ISREG(VFS_I(ip)->i_mode)) {
 
 
 
 
 
 
 
3497		if (XFS_TEST_ERROR(
3498		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3499		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3500		    mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
3501			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3502				"%s: Bad regular inode %Lu, ptr 0x%p",
3503				__func__, ip->i_ino, ip);
3504			goto corrupt_out;
3505		}
3506	} else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3507		if (XFS_TEST_ERROR(
3508		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3509		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3510		    (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3511		    mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
3512			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3513				"%s: Bad directory inode %Lu, ptr 0x%p",
3514				__func__, ip->i_ino, ip);
3515			goto corrupt_out;
3516		}
3517	}
3518	if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3519				ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
3520				XFS_RANDOM_IFLUSH_5)) {
3521		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3522			"%s: detected corrupt incore inode %Lu, "
3523			"total extents = %d, nblocks = %Ld, ptr 0x%p",
3524			__func__, ip->i_ino,
3525			ip->i_d.di_nextents + ip->i_d.di_anextents,
3526			ip->i_d.di_nblocks, ip);
3527		goto corrupt_out;
3528	}
3529	if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3530				mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
3531		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3532			"%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
3533			__func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3534		goto corrupt_out;
3535	}
3536
3537	/*
3538	 * Inode item log recovery for v2 inodes are dependent on the
3539	 * di_flushiter count for correct sequencing. We bump the flush
3540	 * iteration count so we can detect flushes which postdate a log record
3541	 * during recovery. This is redundant as we now log every change and
3542	 * hence this can't happen but we need to still do it to ensure
3543	 * backwards compatibility with old kernels that predate logging all
3544	 * inode changes.
3545	 */
3546	if (ip->i_d.di_version < 3)
3547		ip->i_d.di_flushiter++;
3548
3549	/*
3550	 * Copy the dirty parts of the inode into the on-disk inode.  We always
3551	 * copy out the core of the inode, because if the inode is dirty at all
3552	 * the core must be.
 
3553	 */
3554	xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3555
3556	/* Wrap, we never let the log put out DI_MAX_FLUSH */
3557	if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3558		ip->i_d.di_flushiter = 0;
3559
3560	xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3561	if (XFS_IFORK_Q(ip))
3562		xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3563	xfs_inobp_check(mp, bp);
3564
3565	/*
3566	 * We've recorded everything logged in the inode, so we'd like to clear
3567	 * the ili_fields bits so we don't log and flush things unnecessarily.
3568	 * However, we can't stop logging all this information until the data
3569	 * we've copied into the disk buffer is written to disk.  If we did we
3570	 * might overwrite the copy of the inode in the log with all the data
3571	 * after re-logging only part of it, and in the face of a crash we
3572	 * wouldn't have all the data we need to recover.
3573	 *
3574	 * What we do is move the bits to the ili_last_fields field.  When
3575	 * logging the inode, these bits are moved back to the ili_fields field.
3576	 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3577	 * know that the information those bits represent is permanently on
3578	 * disk.  As long as the flush completes before the inode is logged
3579	 * again, then both ili_fields and ili_last_fields will be cleared.
3580	 *
3581	 * We can play with the ili_fields bits here, because the inode lock
3582	 * must be held exclusively in order to set bits there and the flush
3583	 * lock protects the ili_last_fields bits.  Set ili_logged so the flush
3584	 * done routine can tell whether or not to look in the AIL.  Also, store
3585	 * the current LSN of the inode so that we can tell whether the item has
3586	 * moved in the AIL from xfs_iflush_done().  In order to read the lsn we
3587	 * need the AIL lock, because it is a 64 bit value that cannot be read
3588	 * atomically.
3589	 */
3590	iip->ili_last_fields = iip->ili_fields;
3591	iip->ili_fields = 0;
3592	iip->ili_fsync_fields = 0;
3593	iip->ili_logged = 1;
3594
3595	xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3596				&iip->ili_item.li_lsn);
3597
3598	/*
3599	 * Attach the function xfs_iflush_done to the inode's
3600	 * buffer.  This will remove the inode from the AIL
3601	 * and unlock the inode's flush lock when the inode is
3602	 * completely written to disk.
3603	 */
3604	xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3605
 
 
 
 
3606	/* generate the checksum. */
3607	xfs_dinode_calc_crc(mp, dip);
3608
3609	ASSERT(bp->b_fspriv != NULL);
3610	ASSERT(bp->b_iodone != NULL);
3611	return 0;
3612
3613corrupt_out:
3614	return -EFSCORRUPTED;
3615}