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v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   4 * All Rights Reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
   5 */
   6#include <linux/iversion.h>
   7
   8#include "xfs.h"
   9#include "xfs_fs.h"
  10#include "xfs_shared.h"
  11#include "xfs_format.h"
  12#include "xfs_log_format.h"
  13#include "xfs_trans_resv.h"
 
 
 
  14#include "xfs_mount.h"
  15#include "xfs_defer.h"
  16#include "xfs_inode.h"
 
 
  17#include "xfs_dir2.h"
 
  18#include "xfs_attr.h"
  19#include "xfs_trans_space.h"
  20#include "xfs_trans.h"
  21#include "xfs_buf_item.h"
  22#include "xfs_inode_item.h"
  23#include "xfs_ialloc.h"
  24#include "xfs_bmap.h"
  25#include "xfs_bmap_util.h"
  26#include "xfs_errortag.h"
  27#include "xfs_error.h"
  28#include "xfs_quota.h"
  29#include "xfs_filestream.h"
 
  30#include "xfs_trace.h"
  31#include "xfs_icache.h"
  32#include "xfs_symlink.h"
  33#include "xfs_trans_priv.h"
  34#include "xfs_log.h"
  35#include "xfs_bmap_btree.h"
  36#include "xfs_reflink.h"
  37#include "xfs_ag.h"
  38
  39kmem_zone_t *xfs_inode_zone;
  40
  41/*
  42 * Used in xfs_itruncate_extents().  This is the maximum number of extents
  43 * freed from a file in a single transaction.
  44 */
  45#define	XFS_ITRUNC_MAX_EXTENTS	2
  46
  47STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
  48STATIC int xfs_iunlink_remove(struct xfs_trans *tp, struct xfs_perag *pag,
  49	struct xfs_inode *);
  50
  51/*
  52 * helper function to extract extent size hint from inode
  53 */
  54xfs_extlen_t
  55xfs_get_extsz_hint(
  56	struct xfs_inode	*ip)
  57{
  58	/*
  59	 * No point in aligning allocations if we need to COW to actually
  60	 * write to them.
  61	 */
  62	if (xfs_is_always_cow_inode(ip))
  63		return 0;
  64	if ((ip->i_diflags & XFS_DIFLAG_EXTSIZE) && ip->i_extsize)
  65		return ip->i_extsize;
  66	if (XFS_IS_REALTIME_INODE(ip))
  67		return ip->i_mount->m_sb.sb_rextsize;
  68	return 0;
  69}
  70
  71/*
  72 * Helper function to extract CoW extent size hint from inode.
  73 * Between the extent size hint and the CoW extent size hint, we
  74 * return the greater of the two.  If the value is zero (automatic),
  75 * use the default size.
  76 */
  77xfs_extlen_t
  78xfs_get_cowextsz_hint(
  79	struct xfs_inode	*ip)
  80{
  81	xfs_extlen_t		a, b;
  82
  83	a = 0;
  84	if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
  85		a = ip->i_cowextsize;
  86	b = xfs_get_extsz_hint(ip);
  87
  88	a = max(a, b);
  89	if (a == 0)
  90		return XFS_DEFAULT_COWEXTSZ_HINT;
  91	return a;
  92}
  93
  94/*
  95 * These two are wrapper routines around the xfs_ilock() routine used to
  96 * centralize some grungy code.  They are used in places that wish to lock the
  97 * inode solely for reading the extents.  The reason these places can't just
  98 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
  99 * bringing in of the extents from disk for a file in b-tree format.  If the
 100 * inode is in b-tree format, then we need to lock the inode exclusively until
 101 * the extents are read in.  Locking it exclusively all the time would limit
 102 * our parallelism unnecessarily, though.  What we do instead is check to see
 103 * if the extents have been read in yet, and only lock the inode exclusively
 104 * if they have not.
 105 *
 106 * The functions return a value which should be given to the corresponding
 107 * xfs_iunlock() call.
 108 */
 109uint
 110xfs_ilock_data_map_shared(
 111	struct xfs_inode	*ip)
 112{
 113	uint			lock_mode = XFS_ILOCK_SHARED;
 114
 115	if (xfs_need_iread_extents(&ip->i_df))
 
 116		lock_mode = XFS_ILOCK_EXCL;
 117	xfs_ilock(ip, lock_mode);
 118	return lock_mode;
 119}
 120
 121uint
 122xfs_ilock_attr_map_shared(
 123	struct xfs_inode	*ip)
 124{
 125	uint			lock_mode = XFS_ILOCK_SHARED;
 126
 127	if (ip->i_afp && xfs_need_iread_extents(ip->i_afp))
 
 128		lock_mode = XFS_ILOCK_EXCL;
 129	xfs_ilock(ip, lock_mode);
 130	return lock_mode;
 131}
 132
 133/*
 134 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
 135 * multi-reader locks: i_mmap_lock and the i_lock.  This routine allows
 136 * various combinations of the locks to be obtained.
 137 *
 138 * The 3 locks should always be ordered so that the IO lock is obtained first,
 139 * the mmap lock second and the ilock last in order to prevent deadlock.
 140 *
 141 * Basic locking order:
 142 *
 143 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
 144 *
 145 * mmap_lock locking order:
 146 *
 147 * i_rwsem -> page lock -> mmap_lock
 148 * mmap_lock -> i_mmap_lock -> page_lock
 149 *
 150 * The difference in mmap_lock locking order mean that we cannot hold the
 151 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
 152 * fault in pages during copy in/out (for buffered IO) or require the mmap_lock
 153 * in get_user_pages() to map the user pages into the kernel address space for
 154 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
 155 * page faults already hold the mmap_lock.
 156 *
 157 * Hence to serialise fully against both syscall and mmap based IO, we need to
 158 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
 159 * taken in places where we need to invalidate the page cache in a race
 160 * free manner (e.g. truncate, hole punch and other extent manipulation
 161 * functions).
 162 */
 163void
 164xfs_ilock(
 165	xfs_inode_t		*ip,
 166	uint			lock_flags)
 167{
 168	trace_xfs_ilock(ip, lock_flags, _RET_IP_);
 169
 170	/*
 171	 * You can't set both SHARED and EXCL for the same lock,
 172	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 173	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 174	 */
 175	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 176	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 177	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 178	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 179	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 180	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 181	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 182
 183	if (lock_flags & XFS_IOLOCK_EXCL) {
 184		down_write_nested(&VFS_I(ip)->i_rwsem,
 185				  XFS_IOLOCK_DEP(lock_flags));
 186	} else if (lock_flags & XFS_IOLOCK_SHARED) {
 187		down_read_nested(&VFS_I(ip)->i_rwsem,
 188				 XFS_IOLOCK_DEP(lock_flags));
 189	}
 190
 191	if (lock_flags & XFS_MMAPLOCK_EXCL)
 192		mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
 193	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 194		mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
 195
 196	if (lock_flags & XFS_ILOCK_EXCL)
 197		mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 198	else if (lock_flags & XFS_ILOCK_SHARED)
 199		mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 200}
 201
 202/*
 203 * This is just like xfs_ilock(), except that the caller
 204 * is guaranteed not to sleep.  It returns 1 if it gets
 205 * the requested locks and 0 otherwise.  If the IO lock is
 206 * obtained but the inode lock cannot be, then the IO lock
 207 * is dropped before returning.
 208 *
 209 * ip -- the inode being locked
 210 * lock_flags -- this parameter indicates the inode's locks to be
 211 *       to be locked.  See the comment for xfs_ilock() for a list
 212 *	 of valid values.
 213 */
 214int
 215xfs_ilock_nowait(
 216	xfs_inode_t		*ip,
 217	uint			lock_flags)
 218{
 219	trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
 220
 221	/*
 222	 * You can't set both SHARED and EXCL for the same lock,
 223	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 224	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 225	 */
 226	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 227	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 228	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 229	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 230	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 231	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 232	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 233
 234	if (lock_flags & XFS_IOLOCK_EXCL) {
 235		if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
 236			goto out;
 237	} else if (lock_flags & XFS_IOLOCK_SHARED) {
 238		if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
 239			goto out;
 240	}
 241
 242	if (lock_flags & XFS_MMAPLOCK_EXCL) {
 243		if (!mrtryupdate(&ip->i_mmaplock))
 244			goto out_undo_iolock;
 245	} else if (lock_flags & XFS_MMAPLOCK_SHARED) {
 246		if (!mrtryaccess(&ip->i_mmaplock))
 247			goto out_undo_iolock;
 248	}
 249
 250	if (lock_flags & XFS_ILOCK_EXCL) {
 251		if (!mrtryupdate(&ip->i_lock))
 252			goto out_undo_mmaplock;
 253	} else if (lock_flags & XFS_ILOCK_SHARED) {
 254		if (!mrtryaccess(&ip->i_lock))
 255			goto out_undo_mmaplock;
 256	}
 257	return 1;
 258
 259out_undo_mmaplock:
 260	if (lock_flags & XFS_MMAPLOCK_EXCL)
 261		mrunlock_excl(&ip->i_mmaplock);
 262	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 263		mrunlock_shared(&ip->i_mmaplock);
 264out_undo_iolock:
 265	if (lock_flags & XFS_IOLOCK_EXCL)
 266		up_write(&VFS_I(ip)->i_rwsem);
 267	else if (lock_flags & XFS_IOLOCK_SHARED)
 268		up_read(&VFS_I(ip)->i_rwsem);
 269out:
 270	return 0;
 271}
 272
 273/*
 274 * xfs_iunlock() is used to drop the inode locks acquired with
 275 * xfs_ilock() and xfs_ilock_nowait().  The caller must pass
 276 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
 277 * that we know which locks to drop.
 278 *
 279 * ip -- the inode being unlocked
 280 * lock_flags -- this parameter indicates the inode's locks to be
 281 *       to be unlocked.  See the comment for xfs_ilock() for a list
 282 *	 of valid values for this parameter.
 283 *
 284 */
 285void
 286xfs_iunlock(
 287	xfs_inode_t		*ip,
 288	uint			lock_flags)
 289{
 290	/*
 291	 * You can't set both SHARED and EXCL for the same lock,
 292	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 293	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 294	 */
 295	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 296	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 297	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 298	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 299	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 300	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 301	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 302	ASSERT(lock_flags != 0);
 303
 304	if (lock_flags & XFS_IOLOCK_EXCL)
 305		up_write(&VFS_I(ip)->i_rwsem);
 306	else if (lock_flags & XFS_IOLOCK_SHARED)
 307		up_read(&VFS_I(ip)->i_rwsem);
 308
 309	if (lock_flags & XFS_MMAPLOCK_EXCL)
 310		mrunlock_excl(&ip->i_mmaplock);
 311	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 312		mrunlock_shared(&ip->i_mmaplock);
 313
 314	if (lock_flags & XFS_ILOCK_EXCL)
 315		mrunlock_excl(&ip->i_lock);
 316	else if (lock_flags & XFS_ILOCK_SHARED)
 317		mrunlock_shared(&ip->i_lock);
 318
 319	trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
 320}
 321
 322/*
 323 * give up write locks.  the i/o lock cannot be held nested
 324 * if it is being demoted.
 325 */
 326void
 327xfs_ilock_demote(
 328	xfs_inode_t		*ip,
 329	uint			lock_flags)
 330{
 331	ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
 332	ASSERT((lock_flags &
 333		~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
 334
 335	if (lock_flags & XFS_ILOCK_EXCL)
 336		mrdemote(&ip->i_lock);
 337	if (lock_flags & XFS_MMAPLOCK_EXCL)
 338		mrdemote(&ip->i_mmaplock);
 339	if (lock_flags & XFS_IOLOCK_EXCL)
 340		downgrade_write(&VFS_I(ip)->i_rwsem);
 341
 342	trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
 343}
 344
 345#if defined(DEBUG) || defined(XFS_WARN)
 346int
 347xfs_isilocked(
 348	xfs_inode_t		*ip,
 349	uint			lock_flags)
 350{
 351	if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
 352		if (!(lock_flags & XFS_ILOCK_SHARED))
 353			return !!ip->i_lock.mr_writer;
 354		return rwsem_is_locked(&ip->i_lock.mr_lock);
 355	}
 356
 357	if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
 358		if (!(lock_flags & XFS_MMAPLOCK_SHARED))
 359			return !!ip->i_mmaplock.mr_writer;
 360		return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
 361	}
 362
 363	if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
 364		if (!(lock_flags & XFS_IOLOCK_SHARED))
 365			return !debug_locks ||
 366				lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
 367		return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
 368	}
 369
 370	ASSERT(0);
 371	return 0;
 372}
 373#endif
 374
 375/*
 376 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
 377 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
 378 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
 379 * errors and warnings.
 380 */
 381#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
 382static bool
 383xfs_lockdep_subclass_ok(
 384	int subclass)
 385{
 386	return subclass < MAX_LOCKDEP_SUBCLASSES;
 387}
 388#else
 389#define xfs_lockdep_subclass_ok(subclass)	(true)
 390#endif
 391
 392/*
 393 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
 394 * value. This can be called for any type of inode lock combination, including
 395 * parent locking. Care must be taken to ensure we don't overrun the subclass
 396 * storage fields in the class mask we build.
 397 */
 398static inline int
 399xfs_lock_inumorder(int lock_mode, int subclass)
 400{
 401	int	class = 0;
 402
 403	ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
 404			      XFS_ILOCK_RTSUM)));
 405	ASSERT(xfs_lockdep_subclass_ok(subclass));
 406
 407	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
 408		ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
 409		class += subclass << XFS_IOLOCK_SHIFT;
 410	}
 411
 412	if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
 413		ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
 414		class += subclass << XFS_MMAPLOCK_SHIFT;
 415	}
 416
 417	if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
 418		ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
 419		class += subclass << XFS_ILOCK_SHIFT;
 420	}
 421
 422	return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
 423}
 424
 425/*
 426 * The following routine will lock n inodes in exclusive mode.  We assume the
 427 * caller calls us with the inodes in i_ino order.
 428 *
 429 * We need to detect deadlock where an inode that we lock is in the AIL and we
 430 * start waiting for another inode that is locked by a thread in a long running
 431 * transaction (such as truncate). This can result in deadlock since the long
 432 * running trans might need to wait for the inode we just locked in order to
 433 * push the tail and free space in the log.
 434 *
 435 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
 436 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
 437 * lock more than one at a time, lockdep will report false positives saying we
 438 * have violated locking orders.
 
 
 439 */
 440static void
 441xfs_lock_inodes(
 442	struct xfs_inode	**ips,
 443	int			inodes,
 444	uint			lock_mode)
 445{
 446	int			attempts = 0, i, j, try_lock;
 447	struct xfs_log_item	*lp;
 448
 449	/*
 450	 * Currently supports between 2 and 5 inodes with exclusive locking.  We
 451	 * support an arbitrary depth of locking here, but absolute limits on
 452	 * inodes depend on the type of locking and the limits placed by
 453	 * lockdep annotations in xfs_lock_inumorder.  These are all checked by
 454	 * the asserts.
 455	 */
 456	ASSERT(ips && inodes >= 2 && inodes <= 5);
 457	ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
 458			    XFS_ILOCK_EXCL));
 459	ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
 460			      XFS_ILOCK_SHARED)));
 461	ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
 462		inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
 463	ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
 464		inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
 465
 466	if (lock_mode & XFS_IOLOCK_EXCL) {
 467		ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
 468	} else if (lock_mode & XFS_MMAPLOCK_EXCL)
 469		ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
 470
 471	try_lock = 0;
 472	i = 0;
 
 473again:
 474	for (; i < inodes; i++) {
 475		ASSERT(ips[i]);
 476
 477		if (i && (ips[i] == ips[i - 1]))	/* Already locked */
 478			continue;
 479
 480		/*
 481		 * If try_lock is not set yet, make sure all locked inodes are
 482		 * not in the AIL.  If any are, set try_lock to be used later.
 
 483		 */
 
 484		if (!try_lock) {
 485			for (j = (i - 1); j >= 0 && !try_lock; j--) {
 486				lp = &ips[j]->i_itemp->ili_item;
 487				if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags))
 488					try_lock++;
 
 489			}
 490		}
 491
 492		/*
 493		 * If any of the previous locks we have locked is in the AIL,
 494		 * we must TRY to get the second and subsequent locks. If
 495		 * we can't get any, we must release all we have
 496		 * and try again.
 497		 */
 498		if (!try_lock) {
 499			xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
 500			continue;
 501		}
 502
 503		/* try_lock means we have an inode locked that is in the AIL. */
 504		ASSERT(i != 0);
 505		if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
 506			continue;
 507
 508		/*
 509		 * Unlock all previous guys and try again.  xfs_iunlock will try
 510		 * to push the tail if the inode is in the AIL.
 511		 */
 512		attempts++;
 513		for (j = i - 1; j >= 0; j--) {
 514			/*
 515			 * Check to see if we've already unlocked this one.  Not
 516			 * the first one going back, and the inode ptr is the
 517			 * same.
 518			 */
 519			if (j != (i - 1) && ips[j] == ips[j + 1])
 520				continue;
 521
 522			xfs_iunlock(ips[j], lock_mode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 523		}
 
 524
 525		if ((attempts % 5) == 0) {
 526			delay(1); /* Don't just spin the CPU */
 527		}
 528		i = 0;
 529		try_lock = 0;
 530		goto again;
 
 531	}
 
 532}
 533
 534/*
 535 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
 536 * the mmaplock or the ilock, but not more than one type at a time. If we lock
 537 * more than one at a time, lockdep will report false positives saying we have
 538 * violated locking orders.  The iolock must be double-locked separately since
 539 * we use i_rwsem for that.  We now support taking one lock EXCL and the other
 540 * SHARED.
 541 */
 542void
 543xfs_lock_two_inodes(
 544	struct xfs_inode	*ip0,
 545	uint			ip0_mode,
 546	struct xfs_inode	*ip1,
 547	uint			ip1_mode)
 548{
 549	struct xfs_inode	*temp;
 550	uint			mode_temp;
 551	int			attempts = 0;
 552	struct xfs_log_item	*lp;
 553
 554	ASSERT(hweight32(ip0_mode) == 1);
 555	ASSERT(hweight32(ip1_mode) == 1);
 556	ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
 557	ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
 558	ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 559	       !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 560	ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 561	       !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 562	ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 563	       !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 564	ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 565	       !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 566
 
 
 567	ASSERT(ip0->i_ino != ip1->i_ino);
 568
 569	if (ip0->i_ino > ip1->i_ino) {
 570		temp = ip0;
 571		ip0 = ip1;
 572		ip1 = temp;
 573		mode_temp = ip0_mode;
 574		ip0_mode = ip1_mode;
 575		ip1_mode = mode_temp;
 576	}
 577
 578 again:
 579	xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
 580
 581	/*
 582	 * If the first lock we have locked is in the AIL, we must TRY to get
 583	 * the second lock. If we can't get it, we must release the first one
 584	 * and try again.
 585	 */
 586	lp = &ip0->i_itemp->ili_item;
 587	if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
 588		if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
 589			xfs_iunlock(ip0, ip0_mode);
 590			if ((++attempts % 5) == 0)
 591				delay(1); /* Don't just spin the CPU */
 592			goto again;
 593		}
 594	} else {
 595		xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
 596	}
 597}
 598
 599uint
 600xfs_ip2xflags(
 
 601	struct xfs_inode	*ip)
 602{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 603	uint			flags = 0;
 604
 605	if (ip->i_diflags & XFS_DIFLAG_ANY) {
 606		if (ip->i_diflags & XFS_DIFLAG_REALTIME)
 607			flags |= FS_XFLAG_REALTIME;
 608		if (ip->i_diflags & XFS_DIFLAG_PREALLOC)
 609			flags |= FS_XFLAG_PREALLOC;
 610		if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)
 611			flags |= FS_XFLAG_IMMUTABLE;
 612		if (ip->i_diflags & XFS_DIFLAG_APPEND)
 613			flags |= FS_XFLAG_APPEND;
 614		if (ip->i_diflags & XFS_DIFLAG_SYNC)
 615			flags |= FS_XFLAG_SYNC;
 616		if (ip->i_diflags & XFS_DIFLAG_NOATIME)
 617			flags |= FS_XFLAG_NOATIME;
 618		if (ip->i_diflags & XFS_DIFLAG_NODUMP)
 619			flags |= FS_XFLAG_NODUMP;
 620		if (ip->i_diflags & XFS_DIFLAG_RTINHERIT)
 621			flags |= FS_XFLAG_RTINHERIT;
 622		if (ip->i_diflags & XFS_DIFLAG_PROJINHERIT)
 623			flags |= FS_XFLAG_PROJINHERIT;
 624		if (ip->i_diflags & XFS_DIFLAG_NOSYMLINKS)
 625			flags |= FS_XFLAG_NOSYMLINKS;
 626		if (ip->i_diflags & XFS_DIFLAG_EXTSIZE)
 627			flags |= FS_XFLAG_EXTSIZE;
 628		if (ip->i_diflags & XFS_DIFLAG_EXTSZINHERIT)
 629			flags |= FS_XFLAG_EXTSZINHERIT;
 630		if (ip->i_diflags & XFS_DIFLAG_NODEFRAG)
 631			flags |= FS_XFLAG_NODEFRAG;
 632		if (ip->i_diflags & XFS_DIFLAG_FILESTREAM)
 633			flags |= FS_XFLAG_FILESTREAM;
 634	}
 635
 636	if (ip->i_diflags2 & XFS_DIFLAG2_ANY) {
 637		if (ip->i_diflags2 & XFS_DIFLAG2_DAX)
 638			flags |= FS_XFLAG_DAX;
 639		if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
 640			flags |= FS_XFLAG_COWEXTSIZE;
 641	}
 642
 643	if (XFS_IFORK_Q(ip))
 644		flags |= FS_XFLAG_HASATTR;
 645	return flags;
 646}
 647
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 648/*
 649 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
 650 * is allowed, otherwise it has to be an exact match. If a CI match is found,
 651 * ci_name->name will point to a the actual name (caller must free) or
 652 * will be set to NULL if an exact match is found.
 653 */
 654int
 655xfs_lookup(
 656	xfs_inode_t		*dp,
 657	struct xfs_name		*name,
 658	xfs_inode_t		**ipp,
 659	struct xfs_name		*ci_name)
 660{
 661	xfs_ino_t		inum;
 662	int			error;
 
 663
 664	trace_xfs_lookup(dp, name);
 665
 666	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
 667		return -EIO;
 668
 
 669	error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
 
 
 670	if (error)
 671		goto out_unlock;
 672
 673	error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
 674	if (error)
 675		goto out_free_name;
 676
 677	return 0;
 678
 679out_free_name:
 680	if (ci_name)
 681		kmem_free(ci_name->name);
 682out_unlock:
 683	*ipp = NULL;
 684	return error;
 685}
 686
 687/* Propagate di_flags from a parent inode to a child inode. */
 688static void
 689xfs_inode_inherit_flags(
 690	struct xfs_inode	*ip,
 691	const struct xfs_inode	*pip)
 692{
 693	unsigned int		di_flags = 0;
 694	xfs_failaddr_t		failaddr;
 695	umode_t			mode = VFS_I(ip)->i_mode;
 696
 697	if (S_ISDIR(mode)) {
 698		if (pip->i_diflags & XFS_DIFLAG_RTINHERIT)
 699			di_flags |= XFS_DIFLAG_RTINHERIT;
 700		if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
 701			di_flags |= XFS_DIFLAG_EXTSZINHERIT;
 702			ip->i_extsize = pip->i_extsize;
 703		}
 704		if (pip->i_diflags & XFS_DIFLAG_PROJINHERIT)
 705			di_flags |= XFS_DIFLAG_PROJINHERIT;
 706	} else if (S_ISREG(mode)) {
 707		if ((pip->i_diflags & XFS_DIFLAG_RTINHERIT) &&
 708		    xfs_sb_version_hasrealtime(&ip->i_mount->m_sb))
 709			di_flags |= XFS_DIFLAG_REALTIME;
 710		if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
 711			di_flags |= XFS_DIFLAG_EXTSIZE;
 712			ip->i_extsize = pip->i_extsize;
 713		}
 714	}
 715	if ((pip->i_diflags & XFS_DIFLAG_NOATIME) &&
 716	    xfs_inherit_noatime)
 717		di_flags |= XFS_DIFLAG_NOATIME;
 718	if ((pip->i_diflags & XFS_DIFLAG_NODUMP) &&
 719	    xfs_inherit_nodump)
 720		di_flags |= XFS_DIFLAG_NODUMP;
 721	if ((pip->i_diflags & XFS_DIFLAG_SYNC) &&
 722	    xfs_inherit_sync)
 723		di_flags |= XFS_DIFLAG_SYNC;
 724	if ((pip->i_diflags & XFS_DIFLAG_NOSYMLINKS) &&
 725	    xfs_inherit_nosymlinks)
 726		di_flags |= XFS_DIFLAG_NOSYMLINKS;
 727	if ((pip->i_diflags & XFS_DIFLAG_NODEFRAG) &&
 728	    xfs_inherit_nodefrag)
 729		di_flags |= XFS_DIFLAG_NODEFRAG;
 730	if (pip->i_diflags & XFS_DIFLAG_FILESTREAM)
 731		di_flags |= XFS_DIFLAG_FILESTREAM;
 732
 733	ip->i_diflags |= di_flags;
 734
 735	/*
 736	 * Inode verifiers on older kernels only check that the extent size
 737	 * hint is an integer multiple of the rt extent size on realtime files.
 738	 * They did not check the hint alignment on a directory with both
 739	 * rtinherit and extszinherit flags set.  If the misaligned hint is
 740	 * propagated from a directory into a new realtime file, new file
 741	 * allocations will fail due to math errors in the rt allocator and/or
 742	 * trip the verifiers.  Validate the hint settings in the new file so
 743	 * that we don't let broken hints propagate.
 744	 */
 745	failaddr = xfs_inode_validate_extsize(ip->i_mount, ip->i_extsize,
 746			VFS_I(ip)->i_mode, ip->i_diflags);
 747	if (failaddr) {
 748		ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE |
 749				   XFS_DIFLAG_EXTSZINHERIT);
 750		ip->i_extsize = 0;
 751	}
 752}
 753
 754/* Propagate di_flags2 from a parent inode to a child inode. */
 755static void
 756xfs_inode_inherit_flags2(
 757	struct xfs_inode	*ip,
 758	const struct xfs_inode	*pip)
 759{
 760	xfs_failaddr_t		failaddr;
 761
 762	if (pip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) {
 763		ip->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE;
 764		ip->i_cowextsize = pip->i_cowextsize;
 765	}
 766	if (pip->i_diflags2 & XFS_DIFLAG2_DAX)
 767		ip->i_diflags2 |= XFS_DIFLAG2_DAX;
 768
 769	/* Don't let invalid cowextsize hints propagate. */
 770	failaddr = xfs_inode_validate_cowextsize(ip->i_mount, ip->i_cowextsize,
 771			VFS_I(ip)->i_mode, ip->i_diflags, ip->i_diflags2);
 772	if (failaddr) {
 773		ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE;
 774		ip->i_cowextsize = 0;
 775	}
 776}
 777
 778/*
 779 * Initialise a newly allocated inode and return the in-core inode to the
 780 * caller locked exclusively.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 781 */
 782int
 783xfs_init_new_inode(
 784	struct user_namespace	*mnt_userns,
 785	struct xfs_trans	*tp,
 786	struct xfs_inode	*pip,
 787	xfs_ino_t		ino,
 788	umode_t			mode,
 789	xfs_nlink_t		nlink,
 790	dev_t			rdev,
 791	prid_t			prid,
 792	bool			init_xattrs,
 793	struct xfs_inode	**ipp)
 794{
 795	struct inode		*dir = pip ? VFS_I(pip) : NULL;
 796	struct xfs_mount	*mp = tp->t_mountp;
 797	struct xfs_inode	*ip;
 798	unsigned int		flags;
 799	int			error;
 800	struct timespec64	tv;
 801	struct inode		*inode;
 802
 803	/*
 804	 * Protect against obviously corrupt allocation btree records. Later
 805	 * xfs_iget checks will catch re-allocation of other active in-memory
 806	 * and on-disk inodes. If we don't catch reallocating the parent inode
 807	 * here we will deadlock in xfs_iget() so we have to do these checks
 808	 * first.
 809	 */
 810	if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
 811		xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
 812		return -EFSCORRUPTED;
 
 
 
 
 813	}
 
 814
 815	/*
 816	 * Get the in-core inode with the lock held exclusively to prevent
 817	 * others from looking at until we're done.
 
 818	 */
 819	error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE, XFS_ILOCK_EXCL, &ip);
 
 820	if (error)
 821		return error;
 822
 823	ASSERT(ip != NULL);
 824	inode = VFS_I(ip);
 825	set_nlink(inode, nlink);
 826	inode->i_rdev = rdev;
 827	ip->i_projid = prid;
 828
 829	if (dir && !(dir->i_mode & S_ISGID) &&
 830	    (mp->m_flags & XFS_MOUNT_GRPID)) {
 831		inode_fsuid_set(inode, mnt_userns);
 832		inode->i_gid = dir->i_gid;
 833		inode->i_mode = mode;
 834	} else {
 835		inode_init_owner(mnt_userns, inode, dir, mode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 836	}
 837
 838	/*
 839	 * If the group ID of the new file does not match the effective group
 840	 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
 841	 * (and only if the irix_sgid_inherit compatibility variable is set).
 842	 */
 843	if (irix_sgid_inherit &&
 844	    (inode->i_mode & S_ISGID) &&
 845	    !in_group_p(i_gid_into_mnt(mnt_userns, inode)))
 846		inode->i_mode &= ~S_ISGID;
 847
 848	ip->i_disk_size = 0;
 849	ip->i_df.if_nextents = 0;
 850	ASSERT(ip->i_nblocks == 0);
 851
 852	tv = current_time(inode);
 853	inode->i_mtime = tv;
 854	inode->i_atime = tv;
 855	inode->i_ctime = tv;
 856
 857	ip->i_extsize = 0;
 858	ip->i_diflags = 0;
 859
 860	if (xfs_sb_version_has_v3inode(&mp->m_sb)) {
 861		inode_set_iversion(inode, 1);
 862		ip->i_cowextsize = 0;
 863		ip->i_crtime = tv;
 
 
 
 
 
 
 
 
 
 
 
 
 864	}
 865
 
 866	flags = XFS_ILOG_CORE;
 867	switch (mode & S_IFMT) {
 868	case S_IFIFO:
 869	case S_IFCHR:
 870	case S_IFBLK:
 871	case S_IFSOCK:
 872		ip->i_df.if_format = XFS_DINODE_FMT_DEV;
 
 
 873		flags |= XFS_ILOG_DEV;
 874		break;
 875	case S_IFREG:
 
 
 
 
 
 
 
 876	case S_IFDIR:
 877		if (pip && (pip->i_diflags & XFS_DIFLAG_ANY))
 878			xfs_inode_inherit_flags(ip, pip);
 879		if (pip && (pip->i_diflags2 & XFS_DIFLAG2_ANY))
 880			xfs_inode_inherit_flags2(ip, pip);
 881		fallthrough;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 882	case S_IFLNK:
 883		ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
 884		ip->i_df.if_bytes = 0;
 885		ip->i_df.if_u1.if_root = NULL;
 
 886		break;
 887	default:
 888		ASSERT(0);
 889	}
 890
 891	/*
 892	 * If we need to create attributes immediately after allocating the
 893	 * inode, initialise an empty attribute fork right now. We use the
 894	 * default fork offset for attributes here as we don't know exactly what
 895	 * size or how many attributes we might be adding. We can do this
 896	 * safely here because we know the data fork is completely empty and
 897	 * this saves us from needing to run a separate transaction to set the
 898	 * fork offset in the immediate future.
 899	 */
 900	if (init_xattrs && xfs_sb_version_hasattr(&mp->m_sb)) {
 901		ip->i_forkoff = xfs_default_attroffset(ip) >> 3;
 902		ip->i_afp = xfs_ifork_alloc(XFS_DINODE_FMT_EXTENTS, 0);
 903	}
 904
 905	/*
 906	 * Log the new values stuffed into the inode.
 907	 */
 908	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 909	xfs_trans_log_inode(tp, ip, flags);
 910
 911	/* now that we have an i_mode we can setup the inode structure */
 912	xfs_setup_inode(ip);
 913
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 914	*ipp = ip;
 
 
 915	return 0;
 916}
 917
 918/*
 919 * Decrement the link count on an inode & log the change.  If this causes the
 920 * link count to go to zero, move the inode to AGI unlinked list so that it can
 921 * be freed when the last active reference goes away via xfs_inactive().
 922 */
 923static int			/* error */
 924xfs_droplink(
 925	xfs_trans_t *tp,
 926	xfs_inode_t *ip)
 927{
 
 
 928	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
 929
 
 
 930	drop_nlink(VFS_I(ip));
 931	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 932
 933	if (VFS_I(ip)->i_nlink)
 934		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 935
 936	return xfs_iunlink(tp, ip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 937}
 938
 939/*
 940 * Increment the link count on an inode & log the change.
 941 */
 942static void
 943xfs_bumplink(
 944	xfs_trans_t *tp,
 945	xfs_inode_t *ip)
 946{
 947	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
 948
 
 
 949	inc_nlink(VFS_I(ip));
 
 
 
 
 
 
 
 
 
 
 
 
 
 950	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 
 951}
 952
 953int
 954xfs_create(
 955	struct user_namespace	*mnt_userns,
 956	xfs_inode_t		*dp,
 957	struct xfs_name		*name,
 958	umode_t			mode,
 959	dev_t			rdev,
 960	bool			init_xattrs,
 961	xfs_inode_t		**ipp)
 962{
 963	int			is_dir = S_ISDIR(mode);
 964	struct xfs_mount	*mp = dp->i_mount;
 965	struct xfs_inode	*ip = NULL;
 966	struct xfs_trans	*tp = NULL;
 967	int			error;
 
 
 968	bool                    unlock_dp_on_error = false;
 
 
 969	prid_t			prid;
 970	struct xfs_dquot	*udqp = NULL;
 971	struct xfs_dquot	*gdqp = NULL;
 972	struct xfs_dquot	*pdqp = NULL;
 973	struct xfs_trans_res	*tres;
 974	uint			resblks;
 975	xfs_ino_t		ino;
 976
 977	trace_xfs_create(dp, name);
 978
 979	if (XFS_FORCED_SHUTDOWN(mp))
 980		return -EIO;
 981
 982	prid = xfs_get_initial_prid(dp);
 983
 984	/*
 985	 * Make sure that we have allocated dquot(s) on disk.
 986	 */
 987	error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
 988			mapped_fsgid(mnt_userns), prid,
 989			XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
 990			&udqp, &gdqp, &pdqp);
 991	if (error)
 992		return error;
 993
 994	if (is_dir) {
 
 995		resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
 996		tres = &M_RES(mp)->tr_mkdir;
 
 
 997	} else {
 998		resblks = XFS_CREATE_SPACE_RES(mp, name->len);
 999		tres = &M_RES(mp)->tr_create;
 
 
1000	}
1001
 
 
1002	/*
1003	 * Initially assume that the file does not exist and
1004	 * reserve the resources for that case.  If that is not
1005	 * the case we'll drop the one we have and get a more
1006	 * appropriate transaction later.
1007	 */
1008	error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1009			&tp);
1010	if (error == -ENOSPC) {
1011		/* flush outstanding delalloc blocks and retry */
1012		xfs_flush_inodes(mp);
1013		error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp,
1014				resblks, &tp);
 
 
 
 
 
 
 
 
1015	}
1016	if (error)
1017		goto out_release_dquots;
1018
1019	xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1020	unlock_dp_on_error = true;
1021
1022	error = xfs_iext_count_may_overflow(dp, XFS_DATA_FORK,
1023			XFS_IEXT_DIR_MANIP_CNT(mp));
 
 
 
 
 
 
 
 
 
1024	if (error)
1025		goto out_trans_cancel;
1026
1027	/*
1028	 * A newly created regular or special file just has one directory
1029	 * entry pointing to them, but a directory also the "." entry
1030	 * pointing to itself.
1031	 */
1032	error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1033	if (!error)
1034		error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
1035				is_dir ? 2 : 1, rdev, prid, init_xattrs, &ip);
1036	if (error)
1037		goto out_trans_cancel;
 
1038
1039	/*
1040	 * Now we join the directory inode to the transaction.  We do not do it
1041	 * earlier because xfs_dialloc might commit the previous transaction
1042	 * (and release all the locks).  An error from here on will result in
1043	 * the transaction cancel unlocking dp so don't do it explicitly in the
1044	 * error path.
1045	 */
1046	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1047	unlock_dp_on_error = false;
1048
1049	error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1050					resblks - XFS_IALLOC_SPACE_RES(mp));
 
1051	if (error) {
1052		ASSERT(error != -ENOSPC);
1053		goto out_trans_cancel;
1054	}
1055	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1056	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1057
1058	if (is_dir) {
1059		error = xfs_dir_init(tp, ip, dp);
1060		if (error)
1061			goto out_trans_cancel;
1062
1063		xfs_bumplink(tp, dp);
 
 
1064	}
1065
1066	/*
1067	 * If this is a synchronous mount, make sure that the
1068	 * create transaction goes to disk before returning to
1069	 * the user.
1070	 */
1071	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1072		xfs_trans_set_sync(tp);
1073
1074	/*
1075	 * Attach the dquot(s) to the inodes and modify them incore.
1076	 * These ids of the inode couldn't have changed since the new
1077	 * inode has been locked ever since it was created.
1078	 */
1079	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1080
1081	error = xfs_trans_commit(tp);
 
 
 
 
1082	if (error)
1083		goto out_release_inode;
1084
1085	xfs_qm_dqrele(udqp);
1086	xfs_qm_dqrele(gdqp);
1087	xfs_qm_dqrele(pdqp);
1088
1089	*ipp = ip;
1090	return 0;
1091
 
 
 
 
1092 out_trans_cancel:
1093	xfs_trans_cancel(tp);
1094 out_release_inode:
1095	/*
1096	 * Wait until after the current transaction is aborted to finish the
1097	 * setup of the inode and release the inode.  This prevents recursive
1098	 * transactions and deadlocks from xfs_inactive.
1099	 */
1100	if (ip) {
1101		xfs_finish_inode_setup(ip);
1102		xfs_irele(ip);
1103	}
1104 out_release_dquots:
1105	xfs_qm_dqrele(udqp);
1106	xfs_qm_dqrele(gdqp);
1107	xfs_qm_dqrele(pdqp);
1108
1109	if (unlock_dp_on_error)
1110		xfs_iunlock(dp, XFS_ILOCK_EXCL);
1111	return error;
1112}
1113
1114int
1115xfs_create_tmpfile(
1116	struct user_namespace	*mnt_userns,
1117	struct xfs_inode	*dp,
 
1118	umode_t			mode,
1119	struct xfs_inode	**ipp)
1120{
1121	struct xfs_mount	*mp = dp->i_mount;
1122	struct xfs_inode	*ip = NULL;
1123	struct xfs_trans	*tp = NULL;
1124	int			error;
 
1125	prid_t                  prid;
1126	struct xfs_dquot	*udqp = NULL;
1127	struct xfs_dquot	*gdqp = NULL;
1128	struct xfs_dquot	*pdqp = NULL;
1129	struct xfs_trans_res	*tres;
1130	uint			resblks;
1131	xfs_ino_t		ino;
1132
1133	if (XFS_FORCED_SHUTDOWN(mp))
1134		return -EIO;
1135
1136	prid = xfs_get_initial_prid(dp);
1137
1138	/*
1139	 * Make sure that we have allocated dquot(s) on disk.
1140	 */
1141	error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
1142			mapped_fsgid(mnt_userns), prid,
1143			XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1144			&udqp, &gdqp, &pdqp);
1145	if (error)
1146		return error;
1147
1148	resblks = XFS_IALLOC_SPACE_RES(mp);
1149	tres = &M_RES(mp)->tr_create_tmpfile;
1150
1151	error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1152			&tp);
1153	if (error)
1154		goto out_release_dquots;
 
 
 
 
 
 
 
1155
1156	error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1157	if (!error)
1158		error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
1159				0, 0, prid, false, &ip);
1160	if (error)
1161		goto out_trans_cancel;
1162
 
 
 
 
 
 
 
 
1163	if (mp->m_flags & XFS_MOUNT_WSYNC)
1164		xfs_trans_set_sync(tp);
1165
1166	/*
1167	 * Attach the dquot(s) to the inodes and modify them incore.
1168	 * These ids of the inode couldn't have changed since the new
1169	 * inode has been locked ever since it was created.
1170	 */
1171	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1172
 
1173	error = xfs_iunlink(tp, ip);
1174	if (error)
1175		goto out_trans_cancel;
1176
1177	error = xfs_trans_commit(tp);
1178	if (error)
1179		goto out_release_inode;
1180
1181	xfs_qm_dqrele(udqp);
1182	xfs_qm_dqrele(gdqp);
1183	xfs_qm_dqrele(pdqp);
1184
1185	*ipp = ip;
1186	return 0;
1187
 
 
1188 out_trans_cancel:
1189	xfs_trans_cancel(tp);
1190 out_release_inode:
1191	/*
1192	 * Wait until after the current transaction is aborted to finish the
1193	 * setup of the inode and release the inode.  This prevents recursive
1194	 * transactions and deadlocks from xfs_inactive.
1195	 */
1196	if (ip) {
1197		xfs_finish_inode_setup(ip);
1198		xfs_irele(ip);
1199	}
1200 out_release_dquots:
1201	xfs_qm_dqrele(udqp);
1202	xfs_qm_dqrele(gdqp);
1203	xfs_qm_dqrele(pdqp);
1204
1205	return error;
1206}
1207
1208int
1209xfs_link(
1210	xfs_inode_t		*tdp,
1211	xfs_inode_t		*sip,
1212	struct xfs_name		*target_name)
1213{
1214	xfs_mount_t		*mp = tdp->i_mount;
1215	xfs_trans_t		*tp;
1216	int			error;
 
 
 
 
1217	int			resblks;
1218
1219	trace_xfs_link(tdp, target_name);
1220
1221	ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1222
1223	if (XFS_FORCED_SHUTDOWN(mp))
1224		return -EIO;
1225
1226	error = xfs_qm_dqattach(sip);
1227	if (error)
1228		goto std_return;
1229
1230	error = xfs_qm_dqattach(tdp);
1231	if (error)
1232		goto std_return;
1233
 
 
1234	resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1235	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1236	if (error == -ENOSPC) {
1237		resblks = 0;
1238		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
 
 
 
 
1239	}
1240	if (error)
1241		goto std_return;
1242
1243	xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL);
1244
1245	xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1246	xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1247
1248	error = xfs_iext_count_may_overflow(tdp, XFS_DATA_FORK,
1249			XFS_IEXT_DIR_MANIP_CNT(mp));
1250	if (error)
1251		goto error_return;
1252
1253	/*
1254	 * If we are using project inheritance, we only allow hard link
1255	 * creation in our tree when the project IDs are the same; else
1256	 * the tree quota mechanism could be circumvented.
1257	 */
1258	if (unlikely((tdp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
1259		     tdp->i_projid != sip->i_projid)) {
1260		error = -EXDEV;
1261		goto error_return;
1262	}
1263
1264	if (!resblks) {
1265		error = xfs_dir_canenter(tp, tdp, target_name);
1266		if (error)
1267			goto error_return;
1268	}
1269
1270	/*
1271	 * Handle initial link state of O_TMPFILE inode
1272	 */
1273	if (VFS_I(sip)->i_nlink == 0) {
1274		struct xfs_perag	*pag;
1275
1276		pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sip->i_ino));
1277		error = xfs_iunlink_remove(tp, pag, sip);
1278		xfs_perag_put(pag);
1279		if (error)
1280			goto error_return;
1281	}
1282
1283	error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1284				   resblks);
1285	if (error)
1286		goto error_return;
1287	xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1288	xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1289
1290	xfs_bumplink(tp, sip);
 
 
1291
1292	/*
1293	 * If this is a synchronous mount, make sure that the
1294	 * link transaction goes to disk before returning to
1295	 * the user.
1296	 */
1297	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1298		xfs_trans_set_sync(tp);
 
1299
1300	return xfs_trans_commit(tp);
 
 
 
 
1301
 
 
 
 
1302 error_return:
1303	xfs_trans_cancel(tp);
1304 std_return:
1305	return error;
1306}
1307
1308/* Clear the reflink flag and the cowblocks tag if possible. */
1309static void
1310xfs_itruncate_clear_reflink_flags(
1311	struct xfs_inode	*ip)
1312{
1313	struct xfs_ifork	*dfork;
1314	struct xfs_ifork	*cfork;
1315
1316	if (!xfs_is_reflink_inode(ip))
1317		return;
1318	dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
1319	cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1320	if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1321		ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
1322	if (cfork->if_bytes == 0)
1323		xfs_inode_clear_cowblocks_tag(ip);
1324}
1325
1326/*
1327 * Free up the underlying blocks past new_size.  The new size must be smaller
1328 * than the current size.  This routine can be used both for the attribute and
1329 * data fork, and does not modify the inode size, which is left to the caller.
1330 *
1331 * The transaction passed to this routine must have made a permanent log
1332 * reservation of at least XFS_ITRUNCATE_LOG_RES.  This routine may commit the
1333 * given transaction and start new ones, so make sure everything involved in
1334 * the transaction is tidy before calling here.  Some transaction will be
1335 * returned to the caller to be committed.  The incoming transaction must
1336 * already include the inode, and both inode locks must be held exclusively.
1337 * The inode must also be "held" within the transaction.  On return the inode
1338 * will be "held" within the returned transaction.  This routine does NOT
1339 * require any disk space to be reserved for it within the transaction.
1340 *
1341 * If we get an error, we must return with the inode locked and linked into the
1342 * current transaction. This keeps things simple for the higher level code,
1343 * because it always knows that the inode is locked and held in the transaction
1344 * that returns to it whether errors occur or not.  We don't mark the inode
1345 * dirty on error so that transactions can be easily aborted if possible.
1346 */
1347int
1348xfs_itruncate_extents_flags(
1349	struct xfs_trans	**tpp,
1350	struct xfs_inode	*ip,
1351	int			whichfork,
1352	xfs_fsize_t		new_size,
1353	int			flags)
1354{
1355	struct xfs_mount	*mp = ip->i_mount;
1356	struct xfs_trans	*tp = *tpp;
 
 
 
1357	xfs_fileoff_t		first_unmap_block;
 
1358	xfs_filblks_t		unmap_len;
 
1359	int			error = 0;
 
1360
1361	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1362	ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1363	       xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1364	ASSERT(new_size <= XFS_ISIZE(ip));
1365	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1366	ASSERT(ip->i_itemp != NULL);
1367	ASSERT(ip->i_itemp->ili_lock_flags == 0);
1368	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1369
1370	trace_xfs_itruncate_extents_start(ip, new_size);
1371
1372	flags |= xfs_bmapi_aflag(whichfork);
1373
1374	/*
1375	 * Since it is possible for space to become allocated beyond
1376	 * the end of the file (in a crash where the space is allocated
1377	 * but the inode size is not yet updated), simply remove any
1378	 * blocks which show up between the new EOF and the maximum
1379	 * possible file size.
1380	 *
1381	 * We have to free all the blocks to the bmbt maximum offset, even if
1382	 * the page cache can't scale that far.
1383	 */
1384	first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1385	if (!xfs_verify_fileoff(mp, first_unmap_block)) {
1386		WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF);
1387		return 0;
1388	}
1389
1390	unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1;
1391	while (unmap_len > 0) {
1392		ASSERT(tp->t_firstblock == NULLFSBLOCK);
1393		error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len,
1394				flags, XFS_ITRUNC_MAX_EXTENTS);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1395		if (error)
1396			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1397
1398		/* free the just unmapped extents */
1399		error = xfs_defer_finish(&tp);
1400		if (error)
1401			goto out;
1402	}
1403
1404	if (whichfork == XFS_DATA_FORK) {
1405		/* Remove all pending CoW reservations. */
1406		error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1407				first_unmap_block, XFS_MAX_FILEOFF, true);
 
 
1408		if (error)
1409			goto out;
1410
1411		xfs_itruncate_clear_reflink_flags(ip);
1412	}
1413
1414	/*
1415	 * Always re-log the inode so that our permanent transaction can keep
1416	 * on rolling it forward in the log.
1417	 */
1418	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1419
1420	trace_xfs_itruncate_extents_end(ip, new_size);
1421
1422out:
1423	*tpp = tp;
1424	return error;
 
 
 
 
 
 
 
 
1425}
1426
1427int
1428xfs_release(
1429	xfs_inode_t	*ip)
1430{
1431	xfs_mount_t	*mp = ip->i_mount;
1432	int		error = 0;
1433
1434	if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1435		return 0;
1436
1437	/* If this is a read-only mount, don't do this (would generate I/O) */
1438	if (mp->m_flags & XFS_MOUNT_RDONLY)
1439		return 0;
1440
1441	if (!XFS_FORCED_SHUTDOWN(mp)) {
1442		int truncated;
1443
1444		/*
 
 
 
 
 
 
 
 
 
 
1445		 * If we previously truncated this file and removed old data
1446		 * in the process, we want to initiate "early" writeout on
1447		 * the last close.  This is an attempt to combat the notorious
1448		 * NULL files problem which is particularly noticeable from a
1449		 * truncate down, buffered (re-)write (delalloc), followed by
1450		 * a crash.  What we are effectively doing here is
1451		 * significantly reducing the time window where we'd otherwise
1452		 * be exposed to that problem.
1453		 */
1454		truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1455		if (truncated) {
1456			xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1457			if (ip->i_delayed_blks > 0) {
1458				error = filemap_flush(VFS_I(ip)->i_mapping);
1459				if (error)
1460					return error;
1461			}
1462		}
1463	}
1464
1465	if (VFS_I(ip)->i_nlink == 0)
1466		return 0;
1467
1468	/*
1469	 * If we can't get the iolock just skip truncating the blocks past EOF
1470	 * because we could deadlock with the mmap_lock otherwise. We'll get
1471	 * another chance to drop them once the last reference to the inode is
1472	 * dropped, so we'll never leak blocks permanently.
1473	 */
1474	if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL))
1475		return 0;
1476
1477	if (xfs_can_free_eofblocks(ip, false)) {
 
1478		/*
1479		 * Check if the inode is being opened, written and closed
1480		 * frequently and we have delayed allocation blocks outstanding
1481		 * (e.g. streaming writes from the NFS server), truncating the
1482		 * blocks past EOF will cause fragmentation to occur.
 
 
 
 
 
 
 
1483		 *
1484		 * In this case don't do the truncation, but we have to be
1485		 * careful how we detect this case. Blocks beyond EOF show up as
1486		 * i_delayed_blks even when the inode is clean, so we need to
1487		 * truncate them away first before checking for a dirty release.
1488		 * Hence on the first dirty close we will still remove the
1489		 * speculative allocation, but after that we will leave it in
1490		 * place.
1491		 */
1492		if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1493			goto out_unlock;
1494
1495		error = xfs_free_eofblocks(ip);
1496		if (error)
1497			goto out_unlock;
1498
1499		/* delalloc blocks after truncation means it really is dirty */
1500		if (ip->i_delayed_blks)
1501			xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1502	}
1503
1504out_unlock:
1505	xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1506	return error;
1507}
1508
1509/*
1510 * xfs_inactive_truncate
1511 *
1512 * Called to perform a truncate when an inode becomes unlinked.
1513 */
1514STATIC int
1515xfs_inactive_truncate(
1516	struct xfs_inode *ip)
1517{
1518	struct xfs_mount	*mp = ip->i_mount;
1519	struct xfs_trans	*tp;
1520	int			error;
1521
1522	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
 
1523	if (error) {
1524		ASSERT(XFS_FORCED_SHUTDOWN(mp));
 
1525		return error;
1526	}
 
1527	xfs_ilock(ip, XFS_ILOCK_EXCL);
1528	xfs_trans_ijoin(tp, ip, 0);
1529
1530	/*
1531	 * Log the inode size first to prevent stale data exposure in the event
1532	 * of a system crash before the truncate completes. See the related
1533	 * comment in xfs_vn_setattr_size() for details.
1534	 */
1535	ip->i_disk_size = 0;
1536	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1537
1538	error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1539	if (error)
1540		goto error_trans_cancel;
1541
1542	ASSERT(ip->i_df.if_nextents == 0);
1543
1544	error = xfs_trans_commit(tp);
1545	if (error)
1546		goto error_unlock;
1547
1548	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1549	return 0;
1550
1551error_trans_cancel:
1552	xfs_trans_cancel(tp);
1553error_unlock:
1554	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1555	return error;
1556}
1557
1558/*
1559 * xfs_inactive_ifree()
1560 *
1561 * Perform the inode free when an inode is unlinked.
1562 */
1563STATIC int
1564xfs_inactive_ifree(
1565	struct xfs_inode *ip)
1566{
 
 
 
1567	struct xfs_mount	*mp = ip->i_mount;
1568	struct xfs_trans	*tp;
1569	int			error;
1570
1571	/*
1572	 * We try to use a per-AG reservation for any block needed by the finobt
1573	 * tree, but as the finobt feature predates the per-AG reservation
1574	 * support a degraded file system might not have enough space for the
1575	 * reservation at mount time.  In that case try to dip into the reserved
1576	 * pool and pray.
1577	 *
1578	 * Send a warning if the reservation does happen to fail, as the inode
1579	 * now remains allocated and sits on the unlinked list until the fs is
1580	 * repaired.
1581	 */
1582	if (unlikely(mp->m_finobt_nores)) {
1583		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1584				XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1585				&tp);
1586	} else {
1587		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1588	}
1589	if (error) {
1590		if (error == -ENOSPC) {
1591			xfs_warn_ratelimited(mp,
1592			"Failed to remove inode(s) from unlinked list. "
1593			"Please free space, unmount and run xfs_repair.");
1594		} else {
1595			ASSERT(XFS_FORCED_SHUTDOWN(mp));
1596		}
1597		return error;
1598	}
1599
1600	/*
1601	 * We do not hold the inode locked across the entire rolling transaction
1602	 * here. We only need to hold it for the first transaction that
1603	 * xfs_ifree() builds, which may mark the inode XFS_ISTALE if the
1604	 * underlying cluster buffer is freed. Relogging an XFS_ISTALE inode
1605	 * here breaks the relationship between cluster buffer invalidation and
1606	 * stale inode invalidation on cluster buffer item journal commit
1607	 * completion, and can result in leaving dirty stale inodes hanging
1608	 * around in memory.
1609	 *
1610	 * We have no need for serialising this inode operation against other
1611	 * operations - we freed the inode and hence reallocation is required
1612	 * and that will serialise on reallocating the space the deferops need
1613	 * to free. Hence we can unlock the inode on the first commit of
1614	 * the transaction rather than roll it right through the deferops. This
1615	 * avoids relogging the XFS_ISTALE inode.
1616	 *
1617	 * We check that xfs_ifree() hasn't grown an internal transaction roll
1618	 * by asserting that the inode is still locked when it returns.
1619	 */
1620	xfs_ilock(ip, XFS_ILOCK_EXCL);
1621	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1622
1623	error = xfs_ifree(tp, ip);
1624	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1625	if (error) {
1626		/*
1627		 * If we fail to free the inode, shut down.  The cancel
1628		 * might do that, we need to make sure.  Otherwise the
1629		 * inode might be lost for a long time or forever.
1630		 */
1631		if (!XFS_FORCED_SHUTDOWN(mp)) {
1632			xfs_notice(mp, "%s: xfs_ifree returned error %d",
1633				__func__, error);
1634			xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1635		}
1636		xfs_trans_cancel(tp);
 
1637		return error;
1638	}
1639
1640	/*
1641	 * Credit the quota account(s). The inode is gone.
1642	 */
1643	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1644
1645	/*
1646	 * Just ignore errors at this point.  There is nothing we can do except
1647	 * to try to keep going. Make sure it's not a silent error.
 
1648	 */
1649	error = xfs_trans_commit(tp);
 
 
 
 
1650	if (error)
1651		xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1652			__func__, error);
1653
 
1654	return 0;
1655}
1656
1657/*
1658 * xfs_inactive
1659 *
1660 * This is called when the vnode reference count for the vnode
1661 * goes to zero.  If the file has been unlinked, then it must
1662 * now be truncated.  Also, we clear all of the read-ahead state
1663 * kept for the inode here since the file is now closed.
1664 */
1665void
1666xfs_inactive(
1667	xfs_inode_t	*ip)
1668{
1669	struct xfs_mount	*mp;
1670	int			error;
1671	int			truncate = 0;
1672
1673	/*
1674	 * If the inode is already free, then there can be nothing
1675	 * to clean up here.
1676	 */
1677	if (VFS_I(ip)->i_mode == 0) {
 
1678		ASSERT(ip->i_df.if_broot_bytes == 0);
1679		goto out;
1680	}
1681
1682	mp = ip->i_mount;
1683	ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1684
1685	/* If this is a read-only mount, don't do this (would generate I/O) */
1686	if (mp->m_flags & XFS_MOUNT_RDONLY)
1687		goto out;
1688
1689	/* Metadata inodes require explicit resource cleanup. */
1690	if (xfs_is_metadata_inode(ip))
1691		goto out;
1692
1693	/* Try to clean out the cow blocks if there are any. */
1694	if (xfs_inode_has_cow_data(ip))
1695		xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1696
1697	if (VFS_I(ip)->i_nlink != 0) {
1698		/*
1699		 * force is true because we are evicting an inode from the
1700		 * cache. Post-eof blocks must be freed, lest we end up with
1701		 * broken free space accounting.
1702		 *
1703		 * Note: don't bother with iolock here since lockdep complains
1704		 * about acquiring it in reclaim context. We have the only
1705		 * reference to the inode at this point anyways.
1706		 */
1707		if (xfs_can_free_eofblocks(ip, true))
1708			xfs_free_eofblocks(ip);
1709
1710		goto out;
1711	}
1712
1713	if (S_ISREG(VFS_I(ip)->i_mode) &&
1714	    (ip->i_disk_size != 0 || XFS_ISIZE(ip) != 0 ||
1715	     ip->i_df.if_nextents > 0 || ip->i_delayed_blks > 0))
1716		truncate = 1;
1717
1718	error = xfs_qm_dqattach(ip);
1719	if (error)
1720		goto out;
1721
1722	if (S_ISLNK(VFS_I(ip)->i_mode))
1723		error = xfs_inactive_symlink(ip);
1724	else if (truncate)
1725		error = xfs_inactive_truncate(ip);
1726	if (error)
1727		goto out;
1728
1729	/*
1730	 * If there are attributes associated with the file then blow them away
1731	 * now.  The code calls a routine that recursively deconstructs the
1732	 * attribute fork. If also blows away the in-core attribute fork.
 
1733	 */
1734	if (XFS_IFORK_Q(ip)) {
 
 
1735		error = xfs_attr_inactive(ip);
1736		if (error)
1737			goto out;
1738	}
1739
1740	ASSERT(!ip->i_afp);
1741	ASSERT(ip->i_forkoff == 0);
 
 
1742
1743	/*
1744	 * Free the inode.
1745	 */
1746	xfs_inactive_ifree(ip);
 
 
1747
1748out:
1749	/*
1750	 * We're done making metadata updates for this inode, so we can release
1751	 * the attached dquots.
1752	 */
1753	xfs_qm_dqdetach(ip);
1754}
1755
1756/*
1757 * In-Core Unlinked List Lookups
1758 * =============================
1759 *
1760 * Every inode is supposed to be reachable from some other piece of metadata
1761 * with the exception of the root directory.  Inodes with a connection to a
1762 * file descriptor but not linked from anywhere in the on-disk directory tree
1763 * are collectively known as unlinked inodes, though the filesystem itself
1764 * maintains links to these inodes so that on-disk metadata are consistent.
1765 *
1766 * XFS implements a per-AG on-disk hash table of unlinked inodes.  The AGI
1767 * header contains a number of buckets that point to an inode, and each inode
1768 * record has a pointer to the next inode in the hash chain.  This
1769 * singly-linked list causes scaling problems in the iunlink remove function
1770 * because we must walk that list to find the inode that points to the inode
1771 * being removed from the unlinked hash bucket list.
1772 *
1773 * What if we modelled the unlinked list as a collection of records capturing
1774 * "X.next_unlinked = Y" relations?  If we indexed those records on Y, we'd
1775 * have a fast way to look up unlinked list predecessors, which avoids the
1776 * slow list walk.  That's exactly what we do here (in-core) with a per-AG
1777 * rhashtable.
1778 *
1779 * Because this is a backref cache, we ignore operational failures since the
1780 * iunlink code can fall back to the slow bucket walk.  The only errors that
1781 * should bubble out are for obviously incorrect situations.
1782 *
1783 * All users of the backref cache MUST hold the AGI buffer lock to serialize
1784 * access or have otherwise provided for concurrency control.
1785 */
1786
1787/* Capture a "X.next_unlinked = Y" relationship. */
1788struct xfs_iunlink {
1789	struct rhash_head	iu_rhash_head;
1790	xfs_agino_t		iu_agino;		/* X */
1791	xfs_agino_t		iu_next_unlinked;	/* Y */
1792};
1793
1794/* Unlinked list predecessor lookup hashtable construction */
1795static int
1796xfs_iunlink_obj_cmpfn(
1797	struct rhashtable_compare_arg	*arg,
1798	const void			*obj)
1799{
1800	const xfs_agino_t		*key = arg->key;
1801	const struct xfs_iunlink	*iu = obj;
1802
1803	if (iu->iu_next_unlinked != *key)
1804		return 1;
1805	return 0;
1806}
1807
1808static const struct rhashtable_params xfs_iunlink_hash_params = {
1809	.min_size		= XFS_AGI_UNLINKED_BUCKETS,
1810	.key_len		= sizeof(xfs_agino_t),
1811	.key_offset		= offsetof(struct xfs_iunlink,
1812					   iu_next_unlinked),
1813	.head_offset		= offsetof(struct xfs_iunlink, iu_rhash_head),
1814	.automatic_shrinking	= true,
1815	.obj_cmpfn		= xfs_iunlink_obj_cmpfn,
1816};
1817
1818/*
1819 * Return X, where X.next_unlinked == @agino.  Returns NULLAGINO if no such
1820 * relation is found.
1821 */
1822static xfs_agino_t
1823xfs_iunlink_lookup_backref(
1824	struct xfs_perag	*pag,
1825	xfs_agino_t		agino)
1826{
1827	struct xfs_iunlink	*iu;
1828
1829	iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
1830			xfs_iunlink_hash_params);
1831	return iu ? iu->iu_agino : NULLAGINO;
1832}
1833
1834/*
1835 * Take ownership of an iunlink cache entry and insert it into the hash table.
1836 * If successful, the entry will be owned by the cache; if not, it is freed.
1837 * Either way, the caller does not own @iu after this call.
1838 */
1839static int
1840xfs_iunlink_insert_backref(
1841	struct xfs_perag	*pag,
1842	struct xfs_iunlink	*iu)
1843{
1844	int			error;
1845
1846	error = rhashtable_insert_fast(&pag->pagi_unlinked_hash,
1847			&iu->iu_rhash_head, xfs_iunlink_hash_params);
1848	/*
1849	 * Fail loudly if there already was an entry because that's a sign of
1850	 * corruption of in-memory data.  Also fail loudly if we see an error
1851	 * code we didn't anticipate from the rhashtable code.  Currently we
1852	 * only anticipate ENOMEM.
1853	 */
1854	if (error) {
1855		WARN(error != -ENOMEM, "iunlink cache insert error %d", error);
1856		kmem_free(iu);
1857	}
1858	/*
1859	 * Absorb any runtime errors that aren't a result of corruption because
1860	 * this is a cache and we can always fall back to bucket list scanning.
1861	 */
1862	if (error != 0 && error != -EEXIST)
1863		error = 0;
1864	return error;
1865}
1866
1867/* Remember that @prev_agino.next_unlinked = @this_agino. */
1868static int
1869xfs_iunlink_add_backref(
1870	struct xfs_perag	*pag,
1871	xfs_agino_t		prev_agino,
1872	xfs_agino_t		this_agino)
1873{
1874	struct xfs_iunlink	*iu;
1875
1876	if (XFS_TEST_ERROR(false, pag->pag_mount, XFS_ERRTAG_IUNLINK_FALLBACK))
1877		return 0;
1878
1879	iu = kmem_zalloc(sizeof(*iu), KM_NOFS);
1880	iu->iu_agino = prev_agino;
1881	iu->iu_next_unlinked = this_agino;
1882
1883	return xfs_iunlink_insert_backref(pag, iu);
1884}
1885
1886/*
1887 * Replace X.next_unlinked = @agino with X.next_unlinked = @next_unlinked.
1888 * If @next_unlinked is NULLAGINO, we drop the backref and exit.  If there
1889 * wasn't any such entry then we don't bother.
1890 */
1891static int
1892xfs_iunlink_change_backref(
1893	struct xfs_perag	*pag,
1894	xfs_agino_t		agino,
1895	xfs_agino_t		next_unlinked)
1896{
1897	struct xfs_iunlink	*iu;
1898	int			error;
1899
1900	/* Look up the old entry; if there wasn't one then exit. */
1901	iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
1902			xfs_iunlink_hash_params);
1903	if (!iu)
1904		return 0;
1905
1906	/*
1907	 * Remove the entry.  This shouldn't ever return an error, but if we
1908	 * couldn't remove the old entry we don't want to add it again to the
1909	 * hash table, and if the entry disappeared on us then someone's
1910	 * violated the locking rules and we need to fail loudly.  Either way
1911	 * we cannot remove the inode because internal state is or would have
1912	 * been corrupt.
1913	 */
1914	error = rhashtable_remove_fast(&pag->pagi_unlinked_hash,
1915			&iu->iu_rhash_head, xfs_iunlink_hash_params);
1916	if (error)
1917		return error;
1918
1919	/* If there is no new next entry just free our item and return. */
1920	if (next_unlinked == NULLAGINO) {
1921		kmem_free(iu);
1922		return 0;
1923	}
1924
1925	/* Update the entry and re-add it to the hash table. */
1926	iu->iu_next_unlinked = next_unlinked;
1927	return xfs_iunlink_insert_backref(pag, iu);
1928}
1929
1930/* Set up the in-core predecessor structures. */
1931int
1932xfs_iunlink_init(
1933	struct xfs_perag	*pag)
1934{
1935	return rhashtable_init(&pag->pagi_unlinked_hash,
1936			&xfs_iunlink_hash_params);
1937}
1938
1939/* Free the in-core predecessor structures. */
1940static void
1941xfs_iunlink_free_item(
1942	void			*ptr,
1943	void			*arg)
1944{
1945	struct xfs_iunlink	*iu = ptr;
1946	bool			*freed_anything = arg;
1947
1948	*freed_anything = true;
1949	kmem_free(iu);
1950}
1951
1952void
1953xfs_iunlink_destroy(
1954	struct xfs_perag	*pag)
1955{
1956	bool			freed_anything = false;
1957
1958	rhashtable_free_and_destroy(&pag->pagi_unlinked_hash,
1959			xfs_iunlink_free_item, &freed_anything);
1960
1961	ASSERT(freed_anything == false || XFS_FORCED_SHUTDOWN(pag->pag_mount));
1962}
1963
1964/*
1965 * Point the AGI unlinked bucket at an inode and log the results.  The caller
1966 * is responsible for validating the old value.
1967 */
1968STATIC int
1969xfs_iunlink_update_bucket(
1970	struct xfs_trans	*tp,
1971	struct xfs_perag	*pag,
1972	struct xfs_buf		*agibp,
1973	unsigned int		bucket_index,
1974	xfs_agino_t		new_agino)
1975{
1976	struct xfs_agi		*agi = agibp->b_addr;
1977	xfs_agino_t		old_value;
1978	int			offset;
 
 
 
 
 
 
 
 
 
1979
1980	ASSERT(xfs_verify_agino_or_null(tp->t_mountp, pag->pag_agno, new_agino));
1981
1982	old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
1983	trace_xfs_iunlink_update_bucket(tp->t_mountp, pag->pag_agno, bucket_index,
1984			old_value, new_agino);
1985
1986	/*
1987	 * We should never find the head of the list already set to the value
1988	 * passed in because either we're adding or removing ourselves from the
1989	 * head of the list.
1990	 */
1991	if (old_value == new_agino) {
1992		xfs_buf_mark_corrupt(agibp);
1993		return -EFSCORRUPTED;
1994	}
1995
1996	agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino);
1997	offset = offsetof(struct xfs_agi, agi_unlinked) +
1998			(sizeof(xfs_agino_t) * bucket_index);
1999	xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1);
2000	return 0;
2001}
2002
2003/* Set an on-disk inode's next_unlinked pointer. */
2004STATIC void
2005xfs_iunlink_update_dinode(
2006	struct xfs_trans	*tp,
2007	struct xfs_perag	*pag,
2008	xfs_agino_t		agino,
2009	struct xfs_buf		*ibp,
2010	struct xfs_dinode	*dip,
2011	struct xfs_imap		*imap,
2012	xfs_agino_t		next_agino)
2013{
2014	struct xfs_mount	*mp = tp->t_mountp;
2015	int			offset;
2016
2017	ASSERT(xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino));
2018
2019	trace_xfs_iunlink_update_dinode(mp, pag->pag_agno, agino,
2020			be32_to_cpu(dip->di_next_unlinked), next_agino);
2021
2022	dip->di_next_unlinked = cpu_to_be32(next_agino);
2023	offset = imap->im_boffset +
2024			offsetof(struct xfs_dinode, di_next_unlinked);
2025
2026	/* need to recalc the inode CRC if appropriate */
2027	xfs_dinode_calc_crc(mp, dip);
2028	xfs_trans_inode_buf(tp, ibp);
2029	xfs_trans_log_buf(tp, ibp, offset, offset + sizeof(xfs_agino_t) - 1);
2030}
2031
2032/* Set an in-core inode's unlinked pointer and return the old value. */
2033STATIC int
2034xfs_iunlink_update_inode(
2035	struct xfs_trans	*tp,
2036	struct xfs_inode	*ip,
2037	struct xfs_perag	*pag,
2038	xfs_agino_t		next_agino,
2039	xfs_agino_t		*old_next_agino)
2040{
2041	struct xfs_mount	*mp = tp->t_mountp;
2042	struct xfs_dinode	*dip;
2043	struct xfs_buf		*ibp;
2044	xfs_agino_t		old_value;
2045	int			error;
2046
2047	ASSERT(xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino));
2048
2049	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &ibp);
2050	if (error)
2051		return error;
2052	dip = xfs_buf_offset(ibp, ip->i_imap.im_boffset);
2053
2054	/* Make sure the old pointer isn't garbage. */
2055	old_value = be32_to_cpu(dip->di_next_unlinked);
2056	if (!xfs_verify_agino_or_null(mp, pag->pag_agno, old_value)) {
2057		xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
2058				sizeof(*dip), __this_address);
2059		error = -EFSCORRUPTED;
2060		goto out;
2061	}
2062
2063	/*
2064	 * Since we're updating a linked list, we should never find that the
2065	 * current pointer is the same as the new value, unless we're
2066	 * terminating the list.
2067	 */
2068	*old_next_agino = old_value;
2069	if (old_value == next_agino) {
2070		if (next_agino != NULLAGINO) {
2071			xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
2072					dip, sizeof(*dip), __this_address);
2073			error = -EFSCORRUPTED;
2074		}
2075		goto out;
2076	}
2077
2078	/* Ok, update the new pointer. */
2079	xfs_iunlink_update_dinode(tp, pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
2080			ibp, dip, &ip->i_imap, next_agino);
2081	return 0;
2082out:
2083	xfs_trans_brelse(tp, ibp);
2084	return error;
2085}
2086
2087/*
2088 * This is called when the inode's link count has gone to 0 or we are creating
2089 * a tmpfile via O_TMPFILE.  The inode @ip must have nlink == 0.
2090 *
2091 * We place the on-disk inode on a list in the AGI.  It will be pulled from this
2092 * list when the inode is freed.
2093 */
2094STATIC int
2095xfs_iunlink(
2096	struct xfs_trans	*tp,
2097	struct xfs_inode	*ip)
2098{
2099	struct xfs_mount	*mp = tp->t_mountp;
2100	struct xfs_perag	*pag;
2101	struct xfs_agi		*agi;
2102	struct xfs_buf		*agibp;
2103	xfs_agino_t		next_agino;
2104	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2105	short			bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2106	int			error;
2107
2108	ASSERT(VFS_I(ip)->i_nlink == 0);
2109	ASSERT(VFS_I(ip)->i_mode != 0);
2110	trace_xfs_iunlink(ip);
2111
2112	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2113
2114	/* Get the agi buffer first.  It ensures lock ordering on the list. */
2115	error = xfs_read_agi(mp, tp, pag->pag_agno, &agibp);
2116	if (error)
2117		goto out;
2118	agi = agibp->b_addr;
2119
2120	/*
2121	 * Get the index into the agi hash table for the list this inode will
2122	 * go on.  Make sure the pointer isn't garbage and that this inode
2123	 * isn't already on the list.
2124	 */
2125	next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2126	if (next_agino == agino ||
2127	    !xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino)) {
2128		xfs_buf_mark_corrupt(agibp);
2129		error = -EFSCORRUPTED;
2130		goto out;
2131	}
2132
2133	if (next_agino != NULLAGINO) {
2134		xfs_agino_t		old_agino;
2135
 
2136		/*
2137		 * There is already another inode in the bucket, so point this
2138		 * inode to the current head of the list.
 
 
2139		 */
2140		error = xfs_iunlink_update_inode(tp, ip, pag, next_agino,
2141				&old_agino);
2142		if (error)
2143			goto out;
2144		ASSERT(old_agino == NULLAGINO);
2145
2146		/*
2147		 * agino has been unlinked, add a backref from the next inode
2148		 * back to agino.
2149		 */
2150		error = xfs_iunlink_add_backref(pag, agino, next_agino);
2151		if (error)
2152			goto out;
2153	}
2154
2155	/* Point the head of the list to point to this inode. */
2156	error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
2157out:
2158	xfs_perag_put(pag);
2159	return error;
2160}
2161
2162/* Return the imap, dinode pointer, and buffer for an inode. */
2163STATIC int
2164xfs_iunlink_map_ino(
2165	struct xfs_trans	*tp,
2166	xfs_agnumber_t		agno,
2167	xfs_agino_t		agino,
2168	struct xfs_imap		*imap,
2169	struct xfs_dinode	**dipp,
2170	struct xfs_buf		**bpp)
2171{
2172	struct xfs_mount	*mp = tp->t_mountp;
2173	int			error;
2174
2175	imap->im_blkno = 0;
2176	error = xfs_imap(mp, tp, XFS_AGINO_TO_INO(mp, agno, agino), imap, 0);
2177	if (error) {
2178		xfs_warn(mp, "%s: xfs_imap returned error %d.",
2179				__func__, error);
2180		return error;
2181	}
2182
2183	error = xfs_imap_to_bp(mp, tp, imap, bpp);
2184	if (error) {
2185		xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2186				__func__, error);
2187		return error;
2188	}
2189
2190	*dipp = xfs_buf_offset(*bpp, imap->im_boffset);
2191	return 0;
2192}
2193
2194/*
2195 * Walk the unlinked chain from @head_agino until we find the inode that
2196 * points to @target_agino.  Return the inode number, map, dinode pointer,
2197 * and inode cluster buffer of that inode as @agino, @imap, @dipp, and @bpp.
2198 *
2199 * @tp, @pag, @head_agino, and @target_agino are input parameters.
2200 * @agino, @imap, @dipp, and @bpp are all output parameters.
2201 *
2202 * Do not call this function if @target_agino is the head of the list.
2203 */
2204STATIC int
2205xfs_iunlink_map_prev(
2206	struct xfs_trans	*tp,
2207	struct xfs_perag	*pag,
2208	xfs_agino_t		head_agino,
2209	xfs_agino_t		target_agino,
2210	xfs_agino_t		*agino,
2211	struct xfs_imap		*imap,
2212	struct xfs_dinode	**dipp,
2213	struct xfs_buf		**bpp)
2214{
2215	struct xfs_mount	*mp = tp->t_mountp;
2216	xfs_agino_t		next_agino;
2217	int			error;
2218
2219	ASSERT(head_agino != target_agino);
2220	*bpp = NULL;
2221
2222	/* See if our backref cache can find it faster. */
2223	*agino = xfs_iunlink_lookup_backref(pag, target_agino);
2224	if (*agino != NULLAGINO) {
2225		error = xfs_iunlink_map_ino(tp, pag->pag_agno, *agino, imap,
2226				dipp, bpp);
2227		if (error)
2228			return error;
2229
2230		if (be32_to_cpu((*dipp)->di_next_unlinked) == target_agino)
2231			return 0;
 
 
2232
2233		/*
2234		 * If we get here the cache contents were corrupt, so drop the
2235		 * buffer and fall back to walking the bucket list.
2236		 */
2237		xfs_trans_brelse(tp, *bpp);
2238		*bpp = NULL;
2239		WARN_ON_ONCE(1);
2240	}
2241
2242	trace_xfs_iunlink_map_prev_fallback(mp, pag->pag_agno);
2243
2244	/* Otherwise, walk the entire bucket until we find it. */
2245	next_agino = head_agino;
2246	while (next_agino != target_agino) {
2247		xfs_agino_t	unlinked_agino;
2248
2249		if (*bpp)
2250			xfs_trans_brelse(tp, *bpp);
2251
2252		*agino = next_agino;
2253		error = xfs_iunlink_map_ino(tp, pag->pag_agno, next_agino, imap,
2254				dipp, bpp);
2255		if (error)
2256			return error;
2257
2258		unlinked_agino = be32_to_cpu((*dipp)->di_next_unlinked);
2259		/*
2260		 * Make sure this pointer is valid and isn't an obvious
2261		 * infinite loop.
2262		 */
2263		if (!xfs_verify_agino(mp, pag->pag_agno, unlinked_agino) ||
2264		    next_agino == unlinked_agino) {
2265			XFS_CORRUPTION_ERROR(__func__,
2266					XFS_ERRLEVEL_LOW, mp,
2267					*dipp, sizeof(**dipp));
2268			error = -EFSCORRUPTED;
2269			return error;
2270		}
2271		next_agino = unlinked_agino;
2272	}
2273
 
 
 
 
 
 
 
 
 
2274	return 0;
2275}
2276
2277/*
2278 * Pull the on-disk inode from the AGI unlinked list.
2279 */
2280STATIC int
2281xfs_iunlink_remove(
2282	struct xfs_trans	*tp,
2283	struct xfs_perag	*pag,
2284	struct xfs_inode	*ip)
2285{
2286	struct xfs_mount	*mp = tp->t_mountp;
2287	struct xfs_agi		*agi;
2288	struct xfs_buf		*agibp;
2289	struct xfs_buf		*last_ibp;
2290	struct xfs_dinode	*last_dip = NULL;
2291	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2292	xfs_agino_t		next_agino;
2293	xfs_agino_t		head_agino;
2294	short			bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2295	int			error;
2296
2297	trace_xfs_iunlink_remove(ip);
2298
2299	/* Get the agi buffer first.  It ensures lock ordering on the list. */
2300	error = xfs_read_agi(mp, tp, pag->pag_agno, &agibp);
2301	if (error)
2302		return error;
2303	agi = agibp->b_addr;
2304
2305	/*
2306	 * Get the index into the agi hash table for the list this inode will
2307	 * go on.  Make sure the head pointer isn't garbage.
2308	 */
2309	head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2310	if (!xfs_verify_agino(mp, pag->pag_agno, head_agino)) {
2311		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
2312				agi, sizeof(*agi));
2313		return -EFSCORRUPTED;
2314	}
2315
2316	/*
2317	 * Set our inode's next_unlinked pointer to NULL and then return
2318	 * the old pointer value so that we can update whatever was previous
2319	 * to us in the list to point to whatever was next in the list.
2320	 */
2321	error = xfs_iunlink_update_inode(tp, ip, pag, NULLAGINO, &next_agino);
2322	if (error)
2323		return error;
2324
 
 
2325	/*
2326	 * If there was a backref pointing from the next inode back to this
2327	 * one, remove it because we've removed this inode from the list.
2328	 *
2329	 * Later, if this inode was in the middle of the list we'll update
2330	 * this inode's backref to point from the next inode.
2331	 */
2332	if (next_agino != NULLAGINO) {
2333		error = xfs_iunlink_change_backref(pag, next_agino, NULLAGINO);
2334		if (error)
2335			return error;
2336	}
2337
2338	if (head_agino != agino) {
2339		struct xfs_imap	imap;
2340		xfs_agino_t	prev_agino;
2341
2342		/* We need to search the list for the inode being freed. */
2343		error = xfs_iunlink_map_prev(tp, pag, head_agino, agino,
2344				&prev_agino, &imap, &last_dip, &last_ibp);
2345		if (error)
 
 
 
 
 
2346			return error;
2347
2348		/* Point the previous inode on the list to the next inode. */
2349		xfs_iunlink_update_dinode(tp, pag, prev_agino, last_ibp,
2350				last_dip, &imap, next_agino);
2351
 
 
 
 
 
 
 
 
 
 
 
 
 
2352		/*
2353		 * Now we deal with the backref for this inode.  If this inode
2354		 * pointed at a real inode, change the backref that pointed to
2355		 * us to point to our old next.  If this inode was the end of
2356		 * the list, delete the backref that pointed to us.  Note that
2357		 * change_backref takes care of deleting the backref if
2358		 * next_agino is NULLAGINO.
2359		 */
2360		return xfs_iunlink_change_backref(agibp->b_pag, agino,
2361				next_agino);
2362	}
2363
2364	/* Point the head of the list to the next unlinked inode. */
2365	return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
2366			next_agino);
2367}
2368
2369/*
2370 * Look up the inode number specified and if it is not already marked XFS_ISTALE
2371 * mark it stale. We should only find clean inodes in this lookup that aren't
2372 * already stale.
2373 */
2374static void
2375xfs_ifree_mark_inode_stale(
2376	struct xfs_perag	*pag,
2377	struct xfs_inode	*free_ip,
2378	xfs_ino_t		inum)
2379{
2380	struct xfs_mount	*mp = pag->pag_mount;
2381	struct xfs_inode_log_item *iip;
2382	struct xfs_inode	*ip;
2383
2384retry:
2385	rcu_read_lock();
2386	ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum));
 
 
2387
2388	/* Inode not in memory, nothing to do */
2389	if (!ip) {
2390		rcu_read_unlock();
2391		return;
2392	}
 
 
 
2393
2394	/*
2395	 * because this is an RCU protected lookup, we could find a recently
2396	 * freed or even reallocated inode during the lookup. We need to check
2397	 * under the i_flags_lock for a valid inode here. Skip it if it is not
2398	 * valid, the wrong inode or stale.
2399	 */
2400	spin_lock(&ip->i_flags_lock);
2401	if (ip->i_ino != inum || __xfs_iflags_test(ip, XFS_ISTALE))
2402		goto out_iflags_unlock;
2403
2404	/*
2405	 * Don't try to lock/unlock the current inode, but we _cannot_ skip the
2406	 * other inodes that we did not find in the list attached to the buffer
2407	 * and are not already marked stale. If we can't lock it, back off and
2408	 * retry.
2409	 */
2410	if (ip != free_ip) {
2411		if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2412			spin_unlock(&ip->i_flags_lock);
2413			rcu_read_unlock();
2414			delay(1);
2415			goto retry;
2416		}
2417	}
2418	ip->i_flags |= XFS_ISTALE;
2419
2420	/*
2421	 * If the inode is flushing, it is already attached to the buffer.  All
2422	 * we needed to do here is mark the inode stale so buffer IO completion
2423	 * will remove it from the AIL.
2424	 */
2425	iip = ip->i_itemp;
2426	if (__xfs_iflags_test(ip, XFS_IFLUSHING)) {
2427		ASSERT(!list_empty(&iip->ili_item.li_bio_list));
2428		ASSERT(iip->ili_last_fields);
2429		goto out_iunlock;
2430	}
2431
2432	/*
2433	 * Inodes not attached to the buffer can be released immediately.
2434	 * Everything else has to go through xfs_iflush_abort() on journal
2435	 * commit as the flock synchronises removal of the inode from the
2436	 * cluster buffer against inode reclaim.
2437	 */
2438	if (!iip || list_empty(&iip->ili_item.li_bio_list))
2439		goto out_iunlock;
2440
2441	__xfs_iflags_set(ip, XFS_IFLUSHING);
2442	spin_unlock(&ip->i_flags_lock);
2443	rcu_read_unlock();
2444
2445	/* we have a dirty inode in memory that has not yet been flushed. */
2446	spin_lock(&iip->ili_lock);
2447	iip->ili_last_fields = iip->ili_fields;
2448	iip->ili_fields = 0;
2449	iip->ili_fsync_fields = 0;
2450	spin_unlock(&iip->ili_lock);
2451	ASSERT(iip->ili_last_fields);
 
 
 
2452
2453	if (ip != free_ip)
2454		xfs_iunlock(ip, XFS_ILOCK_EXCL);
2455	return;
2456
2457out_iunlock:
2458	if (ip != free_ip)
2459		xfs_iunlock(ip, XFS_ILOCK_EXCL);
2460out_iflags_unlock:
2461	spin_unlock(&ip->i_flags_lock);
2462	rcu_read_unlock();
2463}
2464
2465/*
2466 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2467 * inodes that are in memory - they all must be marked stale and attached to
2468 * the cluster buffer.
2469 */
2470static int
2471xfs_ifree_cluster(
2472	struct xfs_trans	*tp,
2473	struct xfs_perag	*pag,
2474	struct xfs_inode	*free_ip,
2475	struct xfs_icluster	*xic)
2476{
2477	struct xfs_mount	*mp = free_ip->i_mount;
2478	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2479	struct xfs_buf		*bp;
2480	xfs_daddr_t		blkno;
2481	xfs_ino_t		inum = xic->first_ino;
2482	int			nbufs;
2483	int			i, j;
2484	int			ioffset;
2485	int			error;
 
 
 
 
2486
2487	nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
2488
2489	for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
2490		/*
2491		 * The allocation bitmap tells us which inodes of the chunk were
2492		 * physically allocated. Skip the cluster if an inode falls into
2493		 * a sparse region.
2494		 */
2495		ioffset = inum - xic->first_ino;
2496		if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2497			ASSERT(ioffset % igeo->inodes_per_cluster == 0);
2498			continue;
2499		}
2500
 
2501		blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2502					 XFS_INO_TO_AGBNO(mp, inum));
2503
2504		/*
2505		 * We obtain and lock the backing buffer first in the process
2506		 * here to ensure dirty inodes attached to the buffer remain in
2507		 * the flushing state while we mark them stale.
2508		 *
2509		 * If we scan the in-memory inodes first, then buffer IO can
2510		 * complete before we get a lock on it, and hence we may fail
2511		 * to mark all the active inodes on the buffer stale.
2512		 */
2513		error = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2514				mp->m_bsize * igeo->blocks_per_cluster,
2515				XBF_UNMAPPED, &bp);
2516		if (error)
2517			return error;
 
2518
2519		/*
2520		 * This buffer may not have been correctly initialised as we
2521		 * didn't read it from disk. That's not important because we are
2522		 * only using to mark the buffer as stale in the log, and to
2523		 * attach stale cached inodes on it. That means it will never be
2524		 * dispatched for IO. If it is, we want to know about it, and we
2525		 * want it to fail. We can acheive this by adding a write
2526		 * verifier to the buffer.
2527		 */
2528		bp->b_ops = &xfs_inode_buf_ops;
2529
2530		/*
2531		 * Now we need to set all the cached clean inodes as XFS_ISTALE,
2532		 * too. This requires lookups, and will skip inodes that we've
2533		 * already marked XFS_ISTALE.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2534		 */
2535		for (i = 0; i < igeo->inodes_per_cluster; i++)
2536			xfs_ifree_mark_inode_stale(pag, free_ip, inum + i);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2537
2538		xfs_trans_stale_inode_buf(tp, bp);
2539		xfs_trans_binval(tp, bp);
2540	}
 
 
2541	return 0;
2542}
2543
2544/*
2545 * This is called to return an inode to the inode free list.
2546 * The inode should already be truncated to 0 length and have
2547 * no pages associated with it.  This routine also assumes that
2548 * the inode is already a part of the transaction.
2549 *
2550 * The on-disk copy of the inode will have been added to the list
2551 * of unlinked inodes in the AGI. We need to remove the inode from
2552 * that list atomically with respect to freeing it here.
2553 */
2554int
2555xfs_ifree(
2556	struct xfs_trans	*tp,
2557	struct xfs_inode	*ip)
 
2558{
2559	struct xfs_mount	*mp = ip->i_mount;
2560	struct xfs_perag	*pag;
2561	struct xfs_icluster	xic = { 0 };
2562	struct xfs_inode_log_item *iip = ip->i_itemp;
2563	int			error;
 
 
2564
2565	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2566	ASSERT(VFS_I(ip)->i_nlink == 0);
2567	ASSERT(ip->i_df.if_nextents == 0);
2568	ASSERT(ip->i_disk_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2569	ASSERT(ip->i_nblocks == 0);
2570
2571	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2572
2573	/*
2574	 * Pull the on-disk inode from the AGI unlinked list.
2575	 */
2576	error = xfs_iunlink_remove(tp, pag, ip);
2577	if (error)
2578		goto out;
2579
2580	error = xfs_difree(tp, pag, ip->i_ino, &xic);
2581	if (error)
2582		goto out;
2583
2584	/*
2585	 * Free any local-format data sitting around before we reset the
2586	 * data fork to extents format.  Note that the attr fork data has
2587	 * already been freed by xfs_attr_inactive.
2588	 */
2589	if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
2590		kmem_free(ip->i_df.if_u1.if_data);
2591		ip->i_df.if_u1.if_data = NULL;
2592		ip->i_df.if_bytes = 0;
2593	}
2594
2595	VFS_I(ip)->i_mode = 0;		/* mark incore inode as free */
2596	ip->i_diflags = 0;
2597	ip->i_diflags2 = mp->m_ino_geo.new_diflags2;
2598	ip->i_forkoff = 0;		/* mark the attr fork not in use */
2599	ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
2600	if (xfs_iflags_test(ip, XFS_IPRESERVE_DM_FIELDS))
2601		xfs_iflags_clear(ip, XFS_IPRESERVE_DM_FIELDS);
2602
2603	/* Don't attempt to replay owner changes for a deleted inode */
2604	spin_lock(&iip->ili_lock);
2605	iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER);
2606	spin_unlock(&iip->ili_lock);
2607
 
 
 
 
 
 
2608	/*
2609	 * Bump the generation count so no one will be confused
2610	 * by reincarnations of this inode.
2611	 */
2612	VFS_I(ip)->i_generation++;
2613	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2614
2615	if (xic.deleted)
2616		error = xfs_ifree_cluster(tp, pag, ip, &xic);
2617out:
2618	xfs_perag_put(pag);
2619	return error;
2620}
2621
2622/*
2623 * This is called to unpin an inode.  The caller must have the inode locked
2624 * in at least shared mode so that the buffer cannot be subsequently pinned
2625 * once someone is waiting for it to be unpinned.
2626 */
2627static void
2628xfs_iunpin(
2629	struct xfs_inode	*ip)
2630{
2631	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2632
2633	trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2634
2635	/* Give the log a push to start the unpinning I/O */
2636	xfs_log_force_seq(ip->i_mount, ip->i_itemp->ili_commit_seq, 0, NULL);
2637
2638}
2639
2640static void
2641__xfs_iunpin_wait(
2642	struct xfs_inode	*ip)
2643{
2644	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2645	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2646
2647	xfs_iunpin(ip);
2648
2649	do {
2650		prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2651		if (xfs_ipincount(ip))
2652			io_schedule();
2653	} while (xfs_ipincount(ip));
2654	finish_wait(wq, &wait.wq_entry);
2655}
2656
2657void
2658xfs_iunpin_wait(
2659	struct xfs_inode	*ip)
2660{
2661	if (xfs_ipincount(ip))
2662		__xfs_iunpin_wait(ip);
2663}
2664
2665/*
2666 * Removing an inode from the namespace involves removing the directory entry
2667 * and dropping the link count on the inode. Removing the directory entry can
2668 * result in locking an AGF (directory blocks were freed) and removing a link
2669 * count can result in placing the inode on an unlinked list which results in
2670 * locking an AGI.
2671 *
2672 * The big problem here is that we have an ordering constraint on AGF and AGI
2673 * locking - inode allocation locks the AGI, then can allocate a new extent for
2674 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2675 * removes the inode from the unlinked list, requiring that we lock the AGI
2676 * first, and then freeing the inode can result in an inode chunk being freed
2677 * and hence freeing disk space requiring that we lock an AGF.
2678 *
2679 * Hence the ordering that is imposed by other parts of the code is AGI before
2680 * AGF. This means we cannot remove the directory entry before we drop the inode
2681 * reference count and put it on the unlinked list as this results in a lock
2682 * order of AGF then AGI, and this can deadlock against inode allocation and
2683 * freeing. Therefore we must drop the link counts before we remove the
2684 * directory entry.
2685 *
2686 * This is still safe from a transactional point of view - it is not until we
2687 * get to xfs_defer_finish() that we have the possibility of multiple
2688 * transactions in this operation. Hence as long as we remove the directory
2689 * entry and drop the link count in the first transaction of the remove
2690 * operation, there are no transactional constraints on the ordering here.
2691 */
2692int
2693xfs_remove(
2694	xfs_inode_t             *dp,
2695	struct xfs_name		*name,
2696	xfs_inode_t		*ip)
2697{
2698	xfs_mount_t		*mp = dp->i_mount;
2699	xfs_trans_t             *tp = NULL;
2700	int			is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2701	int                     error = 0;
 
 
 
 
 
2702	uint			resblks;
 
2703
2704	trace_xfs_remove(dp, name);
2705
2706	if (XFS_FORCED_SHUTDOWN(mp))
2707		return -EIO;
2708
2709	error = xfs_qm_dqattach(dp);
2710	if (error)
2711		goto std_return;
2712
2713	error = xfs_qm_dqattach(ip);
2714	if (error)
2715		goto std_return;
2716
 
 
 
 
 
 
 
 
 
2717	/*
2718	 * We try to get the real space reservation first,
2719	 * allowing for directory btree deletion(s) implying
2720	 * possible bmap insert(s).  If we can't get the space
2721	 * reservation then we use 0 instead, and avoid the bmap
2722	 * btree insert(s) in the directory code by, if the bmap
2723	 * insert tries to happen, instead trimming the LAST
2724	 * block from the directory.
2725	 */
2726	resblks = XFS_REMOVE_SPACE_RES(mp);
2727	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2728	if (error == -ENOSPC) {
2729		resblks = 0;
2730		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2731				&tp);
2732	}
2733	if (error) {
2734		ASSERT(error != -ENOSPC);
2735		goto std_return;
 
2736	}
2737
2738	xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
2739
2740	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2741	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2742
2743	/*
2744	 * If we're removing a directory perform some additional validation.
2745	 */
 
2746	if (is_dir) {
2747		ASSERT(VFS_I(ip)->i_nlink >= 2);
2748		if (VFS_I(ip)->i_nlink != 2) {
2749			error = -ENOTEMPTY;
2750			goto out_trans_cancel;
2751		}
2752		if (!xfs_dir_isempty(ip)) {
2753			error = -ENOTEMPTY;
2754			goto out_trans_cancel;
2755		}
2756
2757		/* Drop the link from ip's "..".  */
2758		error = xfs_droplink(tp, dp);
2759		if (error)
2760			goto out_trans_cancel;
2761
2762		/* Drop the "." link from ip to self.  */
2763		error = xfs_droplink(tp, ip);
2764		if (error)
2765			goto out_trans_cancel;
2766
2767		/*
2768		 * Point the unlinked child directory's ".." entry to the root
2769		 * directory to eliminate back-references to inodes that may
2770		 * get freed before the child directory is closed.  If the fs
2771		 * gets shrunk, this can lead to dirent inode validation errors.
2772		 */
2773		if (dp->i_ino != tp->t_mountp->m_sb.sb_rootino) {
2774			error = xfs_dir_replace(tp, ip, &xfs_name_dotdot,
2775					tp->t_mountp->m_sb.sb_rootino, 0);
2776			if (error)
2777				return error;
2778		}
2779	} else {
2780		/*
2781		 * When removing a non-directory we need to log the parent
2782		 * inode here.  For a directory this is done implicitly
2783		 * by the xfs_droplink call for the ".." entry.
2784		 */
2785		xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2786	}
2787	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2788
2789	/* Drop the link from dp to ip. */
2790	error = xfs_droplink(tp, ip);
2791	if (error)
2792		goto out_trans_cancel;
2793
2794	error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
 
 
 
 
 
2795	if (error) {
2796		ASSERT(error != -ENOENT);
2797		goto out_trans_cancel;
2798	}
2799
2800	/*
2801	 * If this is a synchronous mount, make sure that the
2802	 * remove transaction goes to disk before returning to
2803	 * the user.
2804	 */
2805	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2806		xfs_trans_set_sync(tp);
2807
2808	error = xfs_trans_commit(tp);
 
 
 
 
2809	if (error)
2810		goto std_return;
2811
2812	if (is_dir && xfs_inode_is_filestream(ip))
 
 
 
 
 
 
2813		xfs_filestream_deassociate(ip);
2814
2815	return 0;
2816
 
 
2817 out_trans_cancel:
2818	xfs_trans_cancel(tp);
2819 std_return:
2820	return error;
2821}
2822
2823/*
2824 * Enter all inodes for a rename transaction into a sorted array.
2825 */
2826#define __XFS_SORT_INODES	5
2827STATIC void
2828xfs_sort_for_rename(
2829	struct xfs_inode	*dp1,	/* in: old (source) directory inode */
2830	struct xfs_inode	*dp2,	/* in: new (target) directory inode */
2831	struct xfs_inode	*ip1,	/* in: inode of old entry */
2832	struct xfs_inode	*ip2,	/* in: inode of new entry */
2833	struct xfs_inode	*wip,	/* in: whiteout inode */
2834	struct xfs_inode	**i_tab,/* out: sorted array of inodes */
2835	int			*num_inodes)  /* in/out: inodes in array */
2836{
 
2837	int			i, j;
2838
2839	ASSERT(*num_inodes == __XFS_SORT_INODES);
2840	memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2841
2842	/*
2843	 * i_tab contains a list of pointers to inodes.  We initialize
2844	 * the table here & we'll sort it.  We will then use it to
2845	 * order the acquisition of the inode locks.
2846	 *
2847	 * Note that the table may contain duplicates.  e.g., dp1 == dp2.
2848	 */
2849	i = 0;
2850	i_tab[i++] = dp1;
2851	i_tab[i++] = dp2;
2852	i_tab[i++] = ip1;
2853	if (ip2)
2854		i_tab[i++] = ip2;
2855	if (wip)
2856		i_tab[i++] = wip;
2857	*num_inodes = i;
 
2858
2859	/*
2860	 * Sort the elements via bubble sort.  (Remember, there are at
2861	 * most 5 elements to sort, so this is adequate.)
2862	 */
2863	for (i = 0; i < *num_inodes; i++) {
2864		for (j = 1; j < *num_inodes; j++) {
2865			if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2866				struct xfs_inode *temp = i_tab[j];
2867				i_tab[j] = i_tab[j-1];
2868				i_tab[j-1] = temp;
2869			}
2870		}
2871	}
2872}
2873
2874static int
2875xfs_finish_rename(
2876	struct xfs_trans	*tp)
2877{
2878	/*
2879	 * If this is a synchronous mount, make sure that the rename transaction
2880	 * goes to disk before returning to the user.
2881	 */
2882	if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2883		xfs_trans_set_sync(tp);
2884
2885	return xfs_trans_commit(tp);
2886}
2887
2888/*
2889 * xfs_cross_rename()
2890 *
2891 * responsible for handling RENAME_EXCHANGE flag in renameat2() syscall
2892 */
2893STATIC int
2894xfs_cross_rename(
2895	struct xfs_trans	*tp,
2896	struct xfs_inode	*dp1,
2897	struct xfs_name		*name1,
2898	struct xfs_inode	*ip1,
2899	struct xfs_inode	*dp2,
2900	struct xfs_name		*name2,
2901	struct xfs_inode	*ip2,
2902	int			spaceres)
2903{
2904	int		error = 0;
2905	int		ip1_flags = 0;
2906	int		ip2_flags = 0;
2907	int		dp2_flags = 0;
2908
2909	/* Swap inode number for dirent in first parent */
2910	error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
2911	if (error)
2912		goto out_trans_abort;
2913
2914	/* Swap inode number for dirent in second parent */
2915	error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
2916	if (error)
2917		goto out_trans_abort;
2918
2919	/*
2920	 * If we're renaming one or more directories across different parents,
2921	 * update the respective ".." entries (and link counts) to match the new
2922	 * parents.
2923	 */
2924	if (dp1 != dp2) {
2925		dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2926
2927		if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2928			error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2929						dp1->i_ino, spaceres);
2930			if (error)
2931				goto out_trans_abort;
2932
2933			/* transfer ip2 ".." reference to dp1 */
2934			if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2935				error = xfs_droplink(tp, dp2);
2936				if (error)
2937					goto out_trans_abort;
2938				xfs_bumplink(tp, dp1);
2939			}
2940
2941			/*
2942			 * Although ip1 isn't changed here, userspace needs
2943			 * to be warned about the change, so that applications
2944			 * relying on it (like backup ones), will properly
2945			 * notify the change
2946			 */
2947			ip1_flags |= XFS_ICHGTIME_CHG;
2948			ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2949		}
2950
2951		if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2952			error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2953						dp2->i_ino, spaceres);
2954			if (error)
2955				goto out_trans_abort;
2956
2957			/* transfer ip1 ".." reference to dp2 */
2958			if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2959				error = xfs_droplink(tp, dp1);
2960				if (error)
2961					goto out_trans_abort;
2962				xfs_bumplink(tp, dp2);
2963			}
2964
2965			/*
2966			 * Although ip2 isn't changed here, userspace needs
2967			 * to be warned about the change, so that applications
2968			 * relying on it (like backup ones), will properly
2969			 * notify the change
2970			 */
2971			ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2972			ip2_flags |= XFS_ICHGTIME_CHG;
2973		}
2974	}
2975
2976	if (ip1_flags) {
2977		xfs_trans_ichgtime(tp, ip1, ip1_flags);
2978		xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2979	}
2980	if (ip2_flags) {
2981		xfs_trans_ichgtime(tp, ip2, ip2_flags);
2982		xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2983	}
2984	if (dp2_flags) {
2985		xfs_trans_ichgtime(tp, dp2, dp2_flags);
2986		xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2987	}
2988	xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2989	xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2990	return xfs_finish_rename(tp);
2991
2992out_trans_abort:
2993	xfs_trans_cancel(tp);
2994	return error;
2995}
2996
2997/*
2998 * xfs_rename_alloc_whiteout()
2999 *
3000 * Return a referenced, unlinked, unlocked inode that can be used as a
3001 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
3002 * crash between allocating the inode and linking it into the rename transaction
3003 * recovery will free the inode and we won't leak it.
3004 */
3005static int
3006xfs_rename_alloc_whiteout(
3007	struct user_namespace	*mnt_userns,
3008	struct xfs_inode	*dp,
3009	struct xfs_inode	**wip)
3010{
3011	struct xfs_inode	*tmpfile;
3012	int			error;
3013
3014	error = xfs_create_tmpfile(mnt_userns, dp, S_IFCHR | WHITEOUT_MODE,
3015				   &tmpfile);
3016	if (error)
3017		return error;
3018
3019	/*
3020	 * Prepare the tmpfile inode as if it were created through the VFS.
3021	 * Complete the inode setup and flag it as linkable.  nlink is already
3022	 * zero, so we can skip the drop_nlink.
3023	 */
3024	xfs_setup_iops(tmpfile);
3025	xfs_finish_inode_setup(tmpfile);
3026	VFS_I(tmpfile)->i_state |= I_LINKABLE;
3027
3028	*wip = tmpfile;
3029	return 0;
3030}
3031
3032/*
3033 * xfs_rename
3034 */
3035int
3036xfs_rename(
3037	struct user_namespace	*mnt_userns,
3038	struct xfs_inode	*src_dp,
3039	struct xfs_name		*src_name,
3040	struct xfs_inode	*src_ip,
3041	struct xfs_inode	*target_dp,
3042	struct xfs_name		*target_name,
3043	struct xfs_inode	*target_ip,
3044	unsigned int		flags)
3045{
3046	struct xfs_mount	*mp = src_dp->i_mount;
3047	struct xfs_trans	*tp;
3048	struct xfs_inode	*wip = NULL;		/* whiteout inode */
3049	struct xfs_inode	*inodes[__XFS_SORT_INODES];
3050	int			i;
3051	int			num_inodes = __XFS_SORT_INODES;
3052	bool			new_parent = (src_dp != target_dp);
3053	bool			src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
3054	int			spaceres;
3055	int			error;
3056
3057	trace_xfs_rename(src_dp, target_dp, src_name, target_name);
3058
3059	if ((flags & RENAME_EXCHANGE) && !target_ip)
3060		return -EINVAL;
3061
3062	/*
3063	 * If we are doing a whiteout operation, allocate the whiteout inode
3064	 * we will be placing at the target and ensure the type is set
3065	 * appropriately.
3066	 */
3067	if (flags & RENAME_WHITEOUT) {
3068		ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
3069		error = xfs_rename_alloc_whiteout(mnt_userns, target_dp, &wip);
3070		if (error)
3071			return error;
3072
3073		/* setup target dirent info as whiteout */
3074		src_name->type = XFS_DIR3_FT_CHRDEV;
3075	}
3076
3077	xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
3078				inodes, &num_inodes);
3079
 
 
 
3080	spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
3081	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
3082	if (error == -ENOSPC) {
3083		spaceres = 0;
3084		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
3085				&tp);
 
 
 
3086	}
3087	if (error)
3088		goto out_release_wip;
3089
3090	/*
3091	 * Attach the dquots to the inodes
3092	 */
3093	error = xfs_qm_vop_rename_dqattach(inodes);
3094	if (error)
3095		goto out_trans_cancel;
 
 
3096
3097	/*
3098	 * Lock all the participating inodes. Depending upon whether
3099	 * the target_name exists in the target directory, and
3100	 * whether the target directory is the same as the source
3101	 * directory, we can lock from 2 to 4 inodes.
3102	 */
3103	xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
3104
3105	/*
3106	 * Join all the inodes to the transaction. From this point on,
3107	 * we can rely on either trans_commit or trans_cancel to unlock
3108	 * them.
3109	 */
3110	xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
3111	if (new_parent)
3112		xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
3113	xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
3114	if (target_ip)
3115		xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
3116	if (wip)
3117		xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
3118
3119	/*
3120	 * If we are using project inheritance, we only allow renames
3121	 * into our tree when the project IDs are the same; else the
3122	 * tree quota mechanism would be circumvented.
3123	 */
3124	if (unlikely((target_dp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
3125		     target_dp->i_projid != src_ip->i_projid)) {
3126		error = -EXDEV;
3127		goto out_trans_cancel;
3128	}
3129
3130	/* RENAME_EXCHANGE is unique from here on. */
3131	if (flags & RENAME_EXCHANGE)
3132		return xfs_cross_rename(tp, src_dp, src_name, src_ip,
3133					target_dp, target_name, target_ip,
3134					spaceres);
3135
3136	/*
3137	 * Check for expected errors before we dirty the transaction
3138	 * so we can return an error without a transaction abort.
3139	 *
3140	 * Extent count overflow check:
3141	 *
3142	 * From the perspective of src_dp, a rename operation is essentially a
3143	 * directory entry remove operation. Hence the only place where we check
3144	 * for extent count overflow for src_dp is in
3145	 * xfs_bmap_del_extent_real(). xfs_bmap_del_extent_real() returns
3146	 * -ENOSPC when it detects a possible extent count overflow and in
3147	 * response, the higher layers of directory handling code do the
3148	 * following:
3149	 * 1. Data/Free blocks: XFS lets these blocks linger until a
3150	 *    future remove operation removes them.
3151	 * 2. Dabtree blocks: XFS swaps the blocks with the last block in the
3152	 *    Leaf space and unmaps the last block.
3153	 *
3154	 * For target_dp, there are two cases depending on whether the
3155	 * destination directory entry exists or not.
3156	 *
3157	 * When destination directory entry does not exist (i.e. target_ip ==
3158	 * NULL), extent count overflow check is performed only when transaction
3159	 * has a non-zero sized space reservation associated with it.  With a
3160	 * zero-sized space reservation, XFS allows a rename operation to
3161	 * continue only when the directory has sufficient free space in its
3162	 * data/leaf/free space blocks to hold the new entry.
3163	 *
3164	 * When destination directory entry exists (i.e. target_ip != NULL), all
3165	 * we need to do is change the inode number associated with the already
3166	 * existing entry. Hence there is no need to perform an extent count
3167	 * overflow check.
3168	 */
3169	if (target_ip == NULL) {
3170		/*
3171		 * If there's no space reservation, check the entry will
3172		 * fit before actually inserting it.
3173		 */
3174		if (!spaceres) {
3175			error = xfs_dir_canenter(tp, target_dp, target_name);
3176			if (error)
3177				goto out_trans_cancel;
3178		} else {
3179			error = xfs_iext_count_may_overflow(target_dp,
3180					XFS_DATA_FORK,
3181					XFS_IEXT_DIR_MANIP_CNT(mp));
3182			if (error)
3183				goto out_trans_cancel;
3184		}
3185	} else {
3186		/*
3187		 * If target exists and it's a directory, check that whether
3188		 * it can be destroyed.
3189		 */
3190		if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
3191		    (!xfs_dir_isempty(target_ip) ||
3192		     (VFS_I(target_ip)->i_nlink > 2))) {
3193			error = -EEXIST;
3194			goto out_trans_cancel;
3195		}
3196	}
3197
3198	/*
3199	 * Lock the AGI buffers we need to handle bumping the nlink of the
3200	 * whiteout inode off the unlinked list and to handle dropping the
3201	 * nlink of the target inode.  Per locking order rules, do this in
3202	 * increasing AG order and before directory block allocation tries to
3203	 * grab AGFs because we grab AGIs before AGFs.
3204	 *
3205	 * The (vfs) caller must ensure that if src is a directory then
3206	 * target_ip is either null or an empty directory.
3207	 */
3208	for (i = 0; i < num_inodes && inodes[i] != NULL; i++) {
3209		if (inodes[i] == wip ||
3210		    (inodes[i] == target_ip &&
3211		     (VFS_I(target_ip)->i_nlink == 1 || src_is_directory))) {
3212			struct xfs_buf	*bp;
3213			xfs_agnumber_t	agno;
3214
3215			agno = XFS_INO_TO_AGNO(mp, inodes[i]->i_ino);
3216			error = xfs_read_agi(mp, tp, agno, &bp);
3217			if (error)
3218				goto out_trans_cancel;
3219		}
3220	}
3221
3222	/*
3223	 * Directory entry creation below may acquire the AGF. Remove
3224	 * the whiteout from the unlinked list first to preserve correct
3225	 * AGI/AGF locking order. This dirties the transaction so failures
3226	 * after this point will abort and log recovery will clean up the
3227	 * mess.
3228	 *
3229	 * For whiteouts, we need to bump the link count on the whiteout
3230	 * inode. After this point, we have a real link, clear the tmpfile
3231	 * state flag from the inode so it doesn't accidentally get misused
3232	 * in future.
3233	 */
3234	if (wip) {
3235		struct xfs_perag	*pag;
3236
3237		ASSERT(VFS_I(wip)->i_nlink == 0);
3238
3239		pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, wip->i_ino));
3240		error = xfs_iunlink_remove(tp, pag, wip);
3241		xfs_perag_put(pag);
3242		if (error)
3243			goto out_trans_cancel;
3244
3245		xfs_bumplink(tp, wip);
3246		VFS_I(wip)->i_state &= ~I_LINKABLE;
3247	}
3248
3249	/*
3250	 * Set up the target.
3251	 */
3252	if (target_ip == NULL) {
3253		/*
3254		 * If target does not exist and the rename crosses
3255		 * directories, adjust the target directory link count
3256		 * to account for the ".." reference from the new entry.
3257		 */
3258		error = xfs_dir_createname(tp, target_dp, target_name,
3259					   src_ip->i_ino, spaceres);
 
 
 
3260		if (error)
3261			goto out_trans_cancel;
3262
3263		xfs_trans_ichgtime(tp, target_dp,
3264					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3265
3266		if (new_parent && src_is_directory) {
3267			xfs_bumplink(tp, target_dp);
 
 
3268		}
3269	} else { /* target_ip != NULL */
3270		/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3271		 * Link the source inode under the target name.
3272		 * If the source inode is a directory and we are moving
3273		 * it across directories, its ".." entry will be
3274		 * inconsistent until we replace that down below.
3275		 *
3276		 * In case there is already an entry with the same
3277		 * name at the destination directory, remove it first.
3278		 */
3279		error = xfs_dir_replace(tp, target_dp, target_name,
3280					src_ip->i_ino, spaceres);
 
3281		if (error)
3282			goto out_trans_cancel;
3283
3284		xfs_trans_ichgtime(tp, target_dp,
3285					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3286
3287		/*
3288		 * Decrement the link count on the target since the target
3289		 * dir no longer points to it.
3290		 */
3291		error = xfs_droplink(tp, target_ip);
3292		if (error)
3293			goto out_trans_cancel;
3294
3295		if (src_is_directory) {
3296			/*
3297			 * Drop the link from the old "." entry.
3298			 */
3299			error = xfs_droplink(tp, target_ip);
3300			if (error)
3301				goto out_trans_cancel;
3302		}
3303	} /* target_ip != NULL */
3304
3305	/*
3306	 * Remove the source.
3307	 */
3308	if (new_parent && src_is_directory) {
3309		/*
3310		 * Rewrite the ".." entry to point to the new
3311		 * directory.
3312		 */
3313		error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3314					target_dp->i_ino, spaceres);
3315		ASSERT(error != -EEXIST);
 
3316		if (error)
3317			goto out_trans_cancel;
3318	}
3319
3320	/*
3321	 * We always want to hit the ctime on the source inode.
3322	 *
3323	 * This isn't strictly required by the standards since the source
3324	 * inode isn't really being changed, but old unix file systems did
3325	 * it and some incremental backup programs won't work without it.
3326	 */
3327	xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3328	xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3329
3330	/*
3331	 * Adjust the link count on src_dp.  This is necessary when
3332	 * renaming a directory, either within one parent when
3333	 * the target existed, or across two parent directories.
3334	 */
3335	if (src_is_directory && (new_parent || target_ip != NULL)) {
3336
3337		/*
3338		 * Decrement link count on src_directory since the
3339		 * entry that's moved no longer points to it.
3340		 */
3341		error = xfs_droplink(tp, src_dp);
3342		if (error)
3343			goto out_trans_cancel;
3344	}
3345
3346	/*
3347	 * For whiteouts, we only need to update the source dirent with the
3348	 * inode number of the whiteout inode rather than removing it
3349	 * altogether.
3350	 */
3351	if (wip) {
3352		error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3353					spaceres);
3354	} else {
3355		/*
3356		 * NOTE: We don't need to check for extent count overflow here
3357		 * because the dir remove name code will leave the dir block in
3358		 * place if the extent count would overflow.
3359		 */
3360		error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3361					   spaceres);
3362	}
3363
 
 
3364	if (error)
3365		goto out_trans_cancel;
3366
3367	xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3368	xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3369	if (new_parent)
3370		xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3371
3372	error = xfs_finish_rename(tp);
3373	if (wip)
3374		xfs_irele(wip);
3375	return error;
 
 
 
 
 
 
 
 
 
 
 
 
3376
3377out_trans_cancel:
3378	xfs_trans_cancel(tp);
3379out_release_wip:
3380	if (wip)
3381		xfs_irele(wip);
 
 
 
 
 
 
 
3382	return error;
3383}
3384
3385static int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3386xfs_iflush(
3387	struct xfs_inode	*ip,
3388	struct xfs_buf		*bp)
3389{
3390	struct xfs_inode_log_item *iip = ip->i_itemp;
3391	struct xfs_dinode	*dip;
3392	struct xfs_mount	*mp = ip->i_mount;
 
 
3393	int			error;
3394
 
 
3395	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3396	ASSERT(xfs_iflags_test(ip, XFS_IFLUSHING));
3397	ASSERT(ip->i_df.if_format != XFS_DINODE_FMT_BTREE ||
3398	       ip->i_df.if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3399	ASSERT(iip->ili_item.li_buf == bp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3400
3401	dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
 
 
 
 
 
 
 
 
3402
3403	/*
3404	 * We don't flush the inode if any of the following checks fail, but we
3405	 * do still update the log item and attach to the backing buffer as if
3406	 * the flush happened. This is a formality to facilitate predictable
3407	 * error handling as the caller will shutdown and fail the buffer.
3408	 */
3409	error = -EFSCORRUPTED;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3410	if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3411			       mp, XFS_ERRTAG_IFLUSH_1)) {
3412		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3413			"%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT,
3414			__func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3415		goto flush_out;
3416	}
3417	if (S_ISREG(VFS_I(ip)->i_mode)) {
 
 
 
 
 
 
 
3418		if (XFS_TEST_ERROR(
3419		    ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3420		    ip->i_df.if_format != XFS_DINODE_FMT_BTREE,
3421		    mp, XFS_ERRTAG_IFLUSH_3)) {
3422			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3423				"%s: Bad regular inode %Lu, ptr "PTR_FMT,
3424				__func__, ip->i_ino, ip);
3425			goto flush_out;
3426		}
3427	} else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3428		if (XFS_TEST_ERROR(
3429		    ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3430		    ip->i_df.if_format != XFS_DINODE_FMT_BTREE &&
3431		    ip->i_df.if_format != XFS_DINODE_FMT_LOCAL,
3432		    mp, XFS_ERRTAG_IFLUSH_4)) {
3433			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3434				"%s: Bad directory inode %Lu, ptr "PTR_FMT,
3435				__func__, ip->i_ino, ip);
3436			goto flush_out;
3437		}
3438	}
3439	if (XFS_TEST_ERROR(ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp) >
3440				ip->i_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
 
3441		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3442			"%s: detected corrupt incore inode %Lu, "
3443			"total extents = %d, nblocks = %Ld, ptr "PTR_FMT,
3444			__func__, ip->i_ino,
3445			ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp),
3446			ip->i_nblocks, ip);
3447		goto flush_out;
3448	}
3449	if (XFS_TEST_ERROR(ip->i_forkoff > mp->m_sb.sb_inodesize,
3450				mp, XFS_ERRTAG_IFLUSH_6)) {
3451		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3452			"%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT,
3453			__func__, ip->i_ino, ip->i_forkoff, ip);
3454		goto flush_out;
3455	}
3456
3457	/*
3458	 * Inode item log recovery for v2 inodes are dependent on the flushiter
3459	 * count for correct sequencing.  We bump the flush iteration count so
3460	 * we can detect flushes which postdate a log record during recovery.
3461	 * This is redundant as we now log every change and hence this can't
3462	 * happen but we need to still do it to ensure backwards compatibility
3463	 * with old kernels that predate logging all inode changes.
3464	 */
3465	if (!xfs_sb_version_has_v3inode(&mp->m_sb))
3466		ip->i_flushiter++;
3467
3468	/*
3469	 * If there are inline format data / attr forks attached to this inode,
3470	 * make sure they are not corrupt.
3471	 */
3472	if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL &&
3473	    xfs_ifork_verify_local_data(ip))
3474		goto flush_out;
3475	if (ip->i_afp && ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL &&
3476	    xfs_ifork_verify_local_attr(ip))
3477		goto flush_out;
3478
3479	/*
3480	 * Copy the dirty parts of the inode into the on-disk inode.  We always
3481	 * copy out the core of the inode, because if the inode is dirty at all
3482	 * the core must be.
 
3483	 */
3484	xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3485
3486	/* Wrap, we never let the log put out DI_MAX_FLUSH */
3487	if (!xfs_sb_version_has_v3inode(&mp->m_sb)) {
3488		if (ip->i_flushiter == DI_MAX_FLUSH)
3489			ip->i_flushiter = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3490	}
3491
3492	xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3493	if (XFS_IFORK_Q(ip))
3494		xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
 
3495
3496	/*
3497	 * We've recorded everything logged in the inode, so we'd like to clear
3498	 * the ili_fields bits so we don't log and flush things unnecessarily.
3499	 * However, we can't stop logging all this information until the data
3500	 * we've copied into the disk buffer is written to disk.  If we did we
3501	 * might overwrite the copy of the inode in the log with all the data
3502	 * after re-logging only part of it, and in the face of a crash we
3503	 * wouldn't have all the data we need to recover.
3504	 *
3505	 * What we do is move the bits to the ili_last_fields field.  When
3506	 * logging the inode, these bits are moved back to the ili_fields field.
3507	 * In the xfs_buf_inode_iodone() routine we clear ili_last_fields, since
3508	 * we know that the information those bits represent is permanently on
3509	 * disk.  As long as the flush completes before the inode is logged
3510	 * again, then both ili_fields and ili_last_fields will be cleared.
 
 
 
 
 
 
 
 
 
3511	 */
3512	error = 0;
3513flush_out:
3514	spin_lock(&iip->ili_lock);
3515	iip->ili_last_fields = iip->ili_fields;
3516	iip->ili_fields = 0;
3517	iip->ili_fsync_fields = 0;
3518	spin_unlock(&iip->ili_lock);
3519
3520	/*
3521	 * Store the current LSN of the inode so that we can tell whether the
3522	 * item has moved in the AIL from xfs_buf_inode_iodone().
3523	 */
3524	xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3525				&iip->ili_item.li_lsn);
3526
3527	/* generate the checksum. */
3528	xfs_dinode_calc_crc(mp, dip);
3529	return error;
3530}
3531
3532/*
3533 * Non-blocking flush of dirty inode metadata into the backing buffer.
3534 *
3535 * The caller must have a reference to the inode and hold the cluster buffer
3536 * locked. The function will walk across all the inodes on the cluster buffer it
3537 * can find and lock without blocking, and flush them to the cluster buffer.
3538 *
3539 * On successful flushing of at least one inode, the caller must write out the
3540 * buffer and release it. If no inodes are flushed, -EAGAIN will be returned and
3541 * the caller needs to release the buffer. On failure, the filesystem will be
3542 * shut down, the buffer will have been unlocked and released, and EFSCORRUPTED
3543 * will be returned.
3544 */
3545int
3546xfs_iflush_cluster(
3547	struct xfs_buf		*bp)
3548{
3549	struct xfs_mount	*mp = bp->b_mount;
3550	struct xfs_log_item	*lip, *n;
3551	struct xfs_inode	*ip;
3552	struct xfs_inode_log_item *iip;
3553	int			clcount = 0;
3554	int			error = 0;
3555
3556	/*
3557	 * We must use the safe variant here as on shutdown xfs_iflush_abort()
3558	 * can remove itself from the list.
3559	 */
3560	list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
3561		iip = (struct xfs_inode_log_item *)lip;
3562		ip = iip->ili_inode;
3563
3564		/*
3565		 * Quick and dirty check to avoid locks if possible.
3566		 */
3567		if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING))
3568			continue;
3569		if (xfs_ipincount(ip))
3570			continue;
3571
3572		/*
3573		 * The inode is still attached to the buffer, which means it is
3574		 * dirty but reclaim might try to grab it. Check carefully for
3575		 * that, and grab the ilock while still holding the i_flags_lock
3576		 * to guarantee reclaim will not be able to reclaim this inode
3577		 * once we drop the i_flags_lock.
3578		 */
3579		spin_lock(&ip->i_flags_lock);
3580		ASSERT(!__xfs_iflags_test(ip, XFS_ISTALE));
3581		if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING)) {
3582			spin_unlock(&ip->i_flags_lock);
3583			continue;
3584		}
3585
3586		/*
3587		 * ILOCK will pin the inode against reclaim and prevent
3588		 * concurrent transactions modifying the inode while we are
3589		 * flushing the inode. If we get the lock, set the flushing
3590		 * state before we drop the i_flags_lock.
3591		 */
3592		if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
3593			spin_unlock(&ip->i_flags_lock);
3594			continue;
3595		}
3596		__xfs_iflags_set(ip, XFS_IFLUSHING);
3597		spin_unlock(&ip->i_flags_lock);
3598
3599		/*
3600		 * Abort flushing this inode if we are shut down because the
3601		 * inode may not currently be in the AIL. This can occur when
3602		 * log I/O failure unpins the inode without inserting into the
3603		 * AIL, leaving a dirty/unpinned inode attached to the buffer
3604		 * that otherwise looks like it should be flushed.
3605		 */
3606		if (XFS_FORCED_SHUTDOWN(mp)) {
3607			xfs_iunpin_wait(ip);
3608			xfs_iflush_abort(ip);
3609			xfs_iunlock(ip, XFS_ILOCK_SHARED);
3610			error = -EIO;
3611			continue;
3612		}
3613
3614		/* don't block waiting on a log force to unpin dirty inodes */
3615		if (xfs_ipincount(ip)) {
3616			xfs_iflags_clear(ip, XFS_IFLUSHING);
3617			xfs_iunlock(ip, XFS_ILOCK_SHARED);
3618			continue;
3619		}
3620
3621		if (!xfs_inode_clean(ip))
3622			error = xfs_iflush(ip, bp);
3623		else
3624			xfs_iflags_clear(ip, XFS_IFLUSHING);
3625		xfs_iunlock(ip, XFS_ILOCK_SHARED);
3626		if (error)
3627			break;
3628		clcount++;
3629	}
3630
3631	if (error) {
3632		bp->b_flags |= XBF_ASYNC;
3633		xfs_buf_ioend_fail(bp);
3634		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3635		return error;
3636	}
3637
3638	if (!clcount)
3639		return -EAGAIN;
3640
3641	XFS_STATS_INC(mp, xs_icluster_flushcnt);
3642	XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3643	return 0;
3644
3645}
3646
3647/* Release an inode. */
3648void
3649xfs_irele(
3650	struct xfs_inode	*ip)
3651{
3652	trace_xfs_irele(ip, _RET_IP_);
3653	iput(VFS_I(ip));
3654}
3655
3656/*
3657 * Ensure all commited transactions touching the inode are written to the log.
3658 */
3659int
3660xfs_log_force_inode(
3661	struct xfs_inode	*ip)
3662{
3663	xfs_csn_t		seq = 0;
3664
3665	xfs_ilock(ip, XFS_ILOCK_SHARED);
3666	if (xfs_ipincount(ip))
3667		seq = ip->i_itemp->ili_commit_seq;
3668	xfs_iunlock(ip, XFS_ILOCK_SHARED);
3669
3670	if (!seq)
3671		return 0;
3672	return xfs_log_force_seq(ip->i_mount, seq, XFS_LOG_SYNC, NULL);
3673}
3674
3675/*
3676 * Grab the exclusive iolock for a data copy from src to dest, making sure to
3677 * abide vfs locking order (lowest pointer value goes first) and breaking the
3678 * layout leases before proceeding.  The loop is needed because we cannot call
3679 * the blocking break_layout() with the iolocks held, and therefore have to
3680 * back out both locks.
3681 */
3682static int
3683xfs_iolock_two_inodes_and_break_layout(
3684	struct inode		*src,
3685	struct inode		*dest)
3686{
3687	int			error;
3688
3689	if (src > dest)
3690		swap(src, dest);
3691
3692retry:
3693	/* Wait to break both inodes' layouts before we start locking. */
3694	error = break_layout(src, true);
3695	if (error)
3696		return error;
3697	if (src != dest) {
3698		error = break_layout(dest, true);
3699		if (error)
3700			return error;
3701	}
3702
3703	/* Lock one inode and make sure nobody got in and leased it. */
3704	inode_lock(src);
3705	error = break_layout(src, false);
3706	if (error) {
3707		inode_unlock(src);
3708		if (error == -EWOULDBLOCK)
3709			goto retry;
3710		return error;
3711	}
3712
3713	if (src == dest)
3714		return 0;
3715
3716	/* Lock the other inode and make sure nobody got in and leased it. */
3717	inode_lock_nested(dest, I_MUTEX_NONDIR2);
3718	error = break_layout(dest, false);
3719	if (error) {
3720		inode_unlock(src);
3721		inode_unlock(dest);
3722		if (error == -EWOULDBLOCK)
3723			goto retry;
3724		return error;
3725	}
3726
3727	return 0;
3728}
3729
3730/*
3731 * Lock two inodes so that userspace cannot initiate I/O via file syscalls or
3732 * mmap activity.
3733 */
3734int
3735xfs_ilock2_io_mmap(
3736	struct xfs_inode	*ip1,
3737	struct xfs_inode	*ip2)
3738{
3739	int			ret;
3740
3741	ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
3742	if (ret)
3743		return ret;
3744	if (ip1 == ip2)
3745		xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
3746	else
3747		xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL,
3748				    ip2, XFS_MMAPLOCK_EXCL);
3749	return 0;
3750}
3751
3752/* Unlock both inodes to allow IO and mmap activity. */
3753void
3754xfs_iunlock2_io_mmap(
3755	struct xfs_inode	*ip1,
3756	struct xfs_inode	*ip2)
3757{
3758	bool			same_inode = (ip1 == ip2);
3759
3760	xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3761	if (!same_inode)
3762		xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3763	inode_unlock(VFS_I(ip2));
3764	if (!same_inode)
3765		inode_unlock(VFS_I(ip1));
3766}
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}