Linux Audio

Check our new training course

Loading...
v5.4
   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_sb.h"
 
  15#include "xfs_mount.h"
  16#include "xfs_defer.h"
 
 
 
 
  17#include "xfs_inode.h"
  18#include "xfs_dir2.h"
  19#include "xfs_attr.h"
  20#include "xfs_trans_space.h"
  21#include "xfs_trans.h"
  22#include "xfs_buf_item.h"
  23#include "xfs_inode_item.h"
 
 
  24#include "xfs_ialloc.h"
  25#include "xfs_bmap.h"
  26#include "xfs_bmap_util.h"
  27#include "xfs_errortag.h"
  28#include "xfs_error.h"
 
  29#include "xfs_quota.h"
  30#include "xfs_filestream.h"
 
  31#include "xfs_trace.h"
  32#include "xfs_icache.h"
  33#include "xfs_symlink.h"
  34#include "xfs_trans_priv.h"
  35#include "xfs_log.h"
  36#include "xfs_bmap_btree.h"
  37#include "xfs_reflink.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_iflush_int(struct xfs_inode *, struct xfs_buf *);
  48STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
  49STATIC int xfs_iunlink_remove(struct xfs_trans *, 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	if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
  59		return ip->i_d.di_extsize;
  60	if (XFS_IS_REALTIME_INODE(ip))
  61		return ip->i_mount->m_sb.sb_rextsize;
  62	return 0;
  63}
  64
 
  65/*
  66 * Helper function to extract CoW extent size hint from inode.
  67 * Between the extent size hint and the CoW extent size hint, we
  68 * return the greater of the two.  If the value is zero (automatic),
  69 * use the default size.
  70 */
  71xfs_extlen_t
  72xfs_get_cowextsz_hint(
  73	struct xfs_inode	*ip)
 
 
  74{
  75	xfs_extlen_t		a, b;
 
 
  76
  77	a = 0;
  78	if (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
  79		a = ip->i_d.di_cowextsize;
  80	b = xfs_get_extsz_hint(ip);
  81
  82	a = max(a, b);
  83	if (a == 0)
  84		return XFS_DEFAULT_COWEXTSZ_HINT;
  85	return a;
  86}
 
 
 
  87
  88/*
  89 * These two are wrapper routines around the xfs_ilock() routine used to
  90 * centralize some grungy code.  They are used in places that wish to lock the
  91 * inode solely for reading the extents.  The reason these places can't just
  92 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
  93 * bringing in of the extents from disk for a file in b-tree format.  If the
  94 * inode is in b-tree format, then we need to lock the inode exclusively until
  95 * the extents are read in.  Locking it exclusively all the time would limit
  96 * our parallelism unnecessarily, though.  What we do instead is check to see
  97 * if the extents have been read in yet, and only lock the inode exclusively
  98 * if they have not.
  99 *
 100 * The functions return a value which should be given to the corresponding
 101 * xfs_iunlock() call.
 102 */
 103uint
 104xfs_ilock_data_map_shared(
 105	struct xfs_inode	*ip)
 106{
 107	uint			lock_mode = XFS_ILOCK_SHARED;
 108
 109	if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
 110	    (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
 111		lock_mode = XFS_ILOCK_EXCL;
 112	xfs_ilock(ip, lock_mode);
 113	return lock_mode;
 114}
 115
 116uint
 117xfs_ilock_attr_map_shared(
 118	struct xfs_inode	*ip)
 119{
 120	uint			lock_mode = XFS_ILOCK_SHARED;
 121
 122	if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
 123	    (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
 124		lock_mode = XFS_ILOCK_EXCL;
 125	xfs_ilock(ip, lock_mode);
 126	return lock_mode;
 127}
 
 128
 129/*
 130 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
 131 * multi-reader locks: i_mmap_lock and the i_lock.  This routine allows
 132 * various combinations of the locks to be obtained.
 133 *
 134 * The 3 locks should always be ordered so that the IO lock is obtained first,
 135 * the mmap lock second and the ilock last in order to prevent deadlock.
 136 *
 137 * Basic locking order:
 138 *
 139 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
 140 *
 141 * mmap_sem locking order:
 142 *
 143 * i_rwsem -> page lock -> mmap_sem
 144 * mmap_sem -> i_mmap_lock -> page_lock
 145 *
 146 * The difference in mmap_sem locking order mean that we cannot hold the
 147 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
 148 * fault in pages during copy in/out (for buffered IO) or require the mmap_sem
 149 * in get_user_pages() to map the user pages into the kernel address space for
 150 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
 151 * page faults already hold the mmap_sem.
 152 *
 153 * Hence to serialise fully against both syscall and mmap based IO, we need to
 154 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
 155 * taken in places where we need to invalidate the page cache in a race
 156 * free manner (e.g. truncate, hole punch and other extent manipulation
 157 * functions).
 158 */
 159void
 160xfs_ilock(
 161	xfs_inode_t		*ip,
 162	uint			lock_flags)
 
 
 
 
 163{
 164	trace_xfs_ilock(ip, lock_flags, _RET_IP_);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 165
 166	/*
 167	 * You can't set both SHARED and EXCL for the same lock,
 168	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 169	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 170	 */
 171	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 172	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 173	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 174	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 175	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 176	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 177	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 178
 179	if (lock_flags & XFS_IOLOCK_EXCL) {
 180		down_write_nested(&VFS_I(ip)->i_rwsem,
 181				  XFS_IOLOCK_DEP(lock_flags));
 182	} else if (lock_flags & XFS_IOLOCK_SHARED) {
 183		down_read_nested(&VFS_I(ip)->i_rwsem,
 184				 XFS_IOLOCK_DEP(lock_flags));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 185	}
 186
 187	if (lock_flags & XFS_MMAPLOCK_EXCL)
 188		mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
 189	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 190		mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
 191
 192	if (lock_flags & XFS_ILOCK_EXCL)
 193		mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 194	else if (lock_flags & XFS_ILOCK_SHARED)
 195		mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
 196}
 197
 198/*
 199 * This is just like xfs_ilock(), except that the caller
 200 * is guaranteed not to sleep.  It returns 1 if it gets
 201 * the requested locks and 0 otherwise.  If the IO lock is
 202 * obtained but the inode lock cannot be, then the IO lock
 203 * is dropped before returning.
 204 *
 205 * ip -- the inode being locked
 206 * lock_flags -- this parameter indicates the inode's locks to be
 207 *       to be locked.  See the comment for xfs_ilock() for a list
 208 *	 of valid values.
 
 209 */
 210int
 211xfs_ilock_nowait(
 212	xfs_inode_t		*ip,
 213	uint			lock_flags)
 
 
 
 
 
 214{
 215	trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
 
 
 216
 217	/*
 218	 * You can't set both SHARED and EXCL for the same lock,
 219	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 220	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 221	 */
 222	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 223	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 224	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 225	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 226	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 227	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 228	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 229
 230	if (lock_flags & XFS_IOLOCK_EXCL) {
 231		if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
 232			goto out;
 233	} else if (lock_flags & XFS_IOLOCK_SHARED) {
 234		if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
 235			goto out;
 236	}
 237
 238	if (lock_flags & XFS_MMAPLOCK_EXCL) {
 239		if (!mrtryupdate(&ip->i_mmaplock))
 240			goto out_undo_iolock;
 241	} else if (lock_flags & XFS_MMAPLOCK_SHARED) {
 242		if (!mrtryaccess(&ip->i_mmaplock))
 243			goto out_undo_iolock;
 244	}
 245
 246	if (lock_flags & XFS_ILOCK_EXCL) {
 247		if (!mrtryupdate(&ip->i_lock))
 248			goto out_undo_mmaplock;
 249	} else if (lock_flags & XFS_ILOCK_SHARED) {
 250		if (!mrtryaccess(&ip->i_lock))
 251			goto out_undo_mmaplock;
 252	}
 253	return 1;
 254
 255out_undo_mmaplock:
 256	if (lock_flags & XFS_MMAPLOCK_EXCL)
 257		mrunlock_excl(&ip->i_mmaplock);
 258	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 259		mrunlock_shared(&ip->i_mmaplock);
 260out_undo_iolock:
 261	if (lock_flags & XFS_IOLOCK_EXCL)
 262		up_write(&VFS_I(ip)->i_rwsem);
 263	else if (lock_flags & XFS_IOLOCK_SHARED)
 264		up_read(&VFS_I(ip)->i_rwsem);
 265out:
 266	return 0;
 267}
 268
 
 269/*
 270 * xfs_iunlock() is used to drop the inode locks acquired with
 271 * xfs_ilock() and xfs_ilock_nowait().  The caller must pass
 272 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
 273 * that we know which locks to drop.
 
 274 *
 275 * ip -- the inode being unlocked
 276 * lock_flags -- this parameter indicates the inode's locks to be
 277 *       to be unlocked.  See the comment for xfs_ilock() for a list
 278 *	 of valid values for this parameter.
 279 *
 
 
 
 
 
 280 */
 281void
 282xfs_iunlock(
 283	xfs_inode_t		*ip,
 284	uint			lock_flags)
 
 
 
 
 285{
 286	/*
 287	 * You can't set both SHARED and EXCL for the same lock,
 288	 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
 289	 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
 290	 */
 291	ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
 292	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 293	ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
 294	       (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
 295	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 296	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
 297	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
 298	ASSERT(lock_flags != 0);
 299
 300	if (lock_flags & XFS_IOLOCK_EXCL)
 301		up_write(&VFS_I(ip)->i_rwsem);
 302	else if (lock_flags & XFS_IOLOCK_SHARED)
 303		up_read(&VFS_I(ip)->i_rwsem);
 304
 305	if (lock_flags & XFS_MMAPLOCK_EXCL)
 306		mrunlock_excl(&ip->i_mmaplock);
 307	else if (lock_flags & XFS_MMAPLOCK_SHARED)
 308		mrunlock_shared(&ip->i_mmaplock);
 309
 310	if (lock_flags & XFS_ILOCK_EXCL)
 311		mrunlock_excl(&ip->i_lock);
 312	else if (lock_flags & XFS_ILOCK_SHARED)
 313		mrunlock_shared(&ip->i_lock);
 
 
 314
 315	trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
 
 
 316}
 317
 318/*
 319 * give up write locks.  the i/o lock cannot be held nested
 320 * if it is being demoted.
 
 
 
 
 
 321 */
 322void
 323xfs_ilock_demote(
 324	xfs_inode_t		*ip,
 325	uint			lock_flags)
 326{
 327	ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
 328	ASSERT((lock_flags &
 329		~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
 
 330
 331	if (lock_flags & XFS_ILOCK_EXCL)
 332		mrdemote(&ip->i_lock);
 333	if (lock_flags & XFS_MMAPLOCK_EXCL)
 334		mrdemote(&ip->i_mmaplock);
 335	if (lock_flags & XFS_IOLOCK_EXCL)
 336		downgrade_write(&VFS_I(ip)->i_rwsem);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 337
 338	trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
 339}
 
 
 
 
 
 
 
 
 
 
 
 340
 341#if defined(DEBUG) || defined(XFS_WARN)
 342int
 343xfs_isilocked(
 344	xfs_inode_t		*ip,
 345	uint			lock_flags)
 346{
 347	if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
 348		if (!(lock_flags & XFS_ILOCK_SHARED))
 349			return !!ip->i_lock.mr_writer;
 350		return rwsem_is_locked(&ip->i_lock.mr_lock);
 351	}
 
 
 
 
 
 
 352
 353	if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
 354		if (!(lock_flags & XFS_MMAPLOCK_SHARED))
 355			return !!ip->i_mmaplock.mr_writer;
 356		return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
 357	}
 
 
 
 
 
 
 358
 359	if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
 360		if (!(lock_flags & XFS_IOLOCK_SHARED))
 361			return !debug_locks ||
 362				lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
 363		return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 364	}
 
 
 365
 366	ASSERT(0);
 367	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 368}
 369#endif
 370
 371/*
 372 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
 373 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
 374 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
 375 * errors and warnings.
 376 */
 377#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
 378static bool
 379xfs_lockdep_subclass_ok(
 380	int subclass)
 381{
 382	return subclass < MAX_LOCKDEP_SUBCLASSES;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 383}
 384#else
 385#define xfs_lockdep_subclass_ok(subclass)	(true)
 386#endif
 387
 388/*
 389 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
 390 * value. This can be called for any type of inode lock combination, including
 391 * parent locking. Care must be taken to ensure we don't overrun the subclass
 392 * storage fields in the class mask we build.
 
 
 
 393 */
 394static inline int
 395xfs_lock_inumorder(int lock_mode, int subclass)
 396{
 397	int	class = 0;
 398
 399	ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
 400			      XFS_ILOCK_RTSUM)));
 401	ASSERT(xfs_lockdep_subclass_ok(subclass));
 402
 403	if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
 404		ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
 405		class += subclass << XFS_IOLOCK_SHIFT;
 406	}
 407
 408	if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
 409		ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
 410		class += subclass << XFS_MMAPLOCK_SHIFT;
 411	}
 412
 413	if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
 414		ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
 415		class += subclass << XFS_ILOCK_SHIFT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 416	}
 417
 418	return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
 419}
 420
 421/*
 422 * The following routine will lock n inodes in exclusive mode.  We assume the
 423 * caller calls us with the inodes in i_ino order.
 424 *
 425 * We need to detect deadlock where an inode that we lock is in the AIL and we
 426 * start waiting for another inode that is locked by a thread in a long running
 427 * transaction (such as truncate). This can result in deadlock since the long
 428 * running trans might need to wait for the inode we just locked in order to
 429 * push the tail and free space in the log.
 430 *
 431 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
 432 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
 433 * lock more than one at a time, lockdep will report false positives saying we
 434 * have violated locking orders.
 435 */
 436static void
 437xfs_lock_inodes(
 438	struct xfs_inode	**ips,
 439	int			inodes,
 440	uint			lock_mode)
 441{
 442	int			attempts = 0, i, j, try_lock;
 443	struct xfs_log_item	*lp;
 444
 445	/*
 446	 * Currently supports between 2 and 5 inodes with exclusive locking.  We
 447	 * support an arbitrary depth of locking here, but absolute limits on
 448	 * inodes depend on the the type of locking and the limits placed by
 449	 * lockdep annotations in xfs_lock_inumorder.  These are all checked by
 450	 * the asserts.
 451	 */
 452	ASSERT(ips && inodes >= 2 && inodes <= 5);
 453	ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
 454			    XFS_ILOCK_EXCL));
 455	ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
 456			      XFS_ILOCK_SHARED)));
 457	ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
 458		inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
 459	ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
 460		inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
 461
 462	if (lock_mode & XFS_IOLOCK_EXCL) {
 463		ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
 464	} else if (lock_mode & XFS_MMAPLOCK_EXCL)
 465		ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
 466
 467	try_lock = 0;
 468	i = 0;
 469again:
 470	for (; i < inodes; i++) {
 471		ASSERT(ips[i]);
 472
 473		if (i && (ips[i] == ips[i - 1]))	/* Already locked */
 474			continue;
 475
 476		/*
 477		 * If try_lock is not set yet, make sure all locked inodes are
 478		 * not in the AIL.  If any are, set try_lock to be used later.
 479		 */
 480		if (!try_lock) {
 481			for (j = (i - 1); j >= 0 && !try_lock; j--) {
 482				lp = &ips[j]->i_itemp->ili_item;
 483				if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags))
 484					try_lock++;
 485			}
 486		}
 487
 488		/*
 489		 * If any of the previous locks we have locked is in the AIL,
 490		 * we must TRY to get the second and subsequent locks. If
 491		 * we can't get any, we must release all we have
 492		 * and try again.
 493		 */
 494		if (!try_lock) {
 495			xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
 496			continue;
 497		}
 498
 499		/* try_lock means we have an inode locked that is in the AIL. */
 500		ASSERT(i != 0);
 501		if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
 502			continue;
 503
 504		/*
 505		 * Unlock all previous guys and try again.  xfs_iunlock will try
 506		 * to push the tail if the inode is in the AIL.
 507		 */
 508		attempts++;
 509		for (j = i - 1; j >= 0; j--) {
 510			/*
 511			 * Check to see if we've already unlocked this one.  Not
 512			 * the first one going back, and the inode ptr is the
 513			 * same.
 514			 */
 515			if (j != (i - 1) && ips[j] == ips[j + 1])
 516				continue;
 517
 518			xfs_iunlock(ips[j], lock_mode);
 519		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 520
 521		if ((attempts % 5) == 0) {
 522			delay(1); /* Don't just spin the CPU */
 523		}
 524		i = 0;
 525		try_lock = 0;
 526		goto again;
 527	}
 528}
 529
 530/*
 531 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
 532 * the mmaplock or the ilock, but not more than one type at a time. If we lock
 533 * more than one at a time, lockdep will report false positives saying we have
 534 * violated locking orders.  The iolock must be double-locked separately since
 535 * we use i_rwsem for that.  We now support taking one lock EXCL and the other
 536 * SHARED.
 537 */
 538void
 539xfs_lock_two_inodes(
 540	struct xfs_inode	*ip0,
 541	uint			ip0_mode,
 542	struct xfs_inode	*ip1,
 543	uint			ip1_mode)
 544{
 545	struct xfs_inode	*temp;
 546	uint			mode_temp;
 547	int			attempts = 0;
 548	struct xfs_log_item	*lp;
 549
 550	ASSERT(hweight32(ip0_mode) == 1);
 551	ASSERT(hweight32(ip1_mode) == 1);
 552	ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
 553	ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
 554	ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 555	       !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 556	ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 557	       !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 558	ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 559	       !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 560	ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
 561	       !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
 562
 563	ASSERT(ip0->i_ino != ip1->i_ino);
 564
 565	if (ip0->i_ino > ip1->i_ino) {
 566		temp = ip0;
 567		ip0 = ip1;
 568		ip1 = temp;
 569		mode_temp = ip0_mode;
 570		ip0_mode = ip1_mode;
 571		ip1_mode = mode_temp;
 572	}
 573
 574 again:
 575	xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
 576
 577	/*
 578	 * If the first lock we have locked is in the AIL, we must TRY to get
 579	 * the second lock. If we can't get it, we must release the first one
 580	 * and try again.
 581	 */
 582	lp = &ip0->i_itemp->ili_item;
 583	if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
 584		if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
 585			xfs_iunlock(ip0, ip0_mode);
 586			if ((++attempts % 5) == 0)
 587				delay(1); /* Don't just spin the CPU */
 588			goto again;
 589		}
 590	} else {
 591		xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
 592	}
 593}
 594
 595void
 596__xfs_iflock(
 597	struct xfs_inode	*ip)
 598{
 599	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
 600	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
 601
 602	do {
 603		prepare_to_wait_exclusive(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
 604		if (xfs_isiflocked(ip))
 605			io_schedule();
 606	} while (!xfs_iflock_nowait(ip));
 607
 608	finish_wait(wq, &wait.wq_entry);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 609}
 610
 611STATIC uint
 612_xfs_dic2xflags(
 613	uint16_t		di_flags,
 614	uint64_t		di_flags2,
 615	bool			has_attr)
 616{
 617	uint			flags = 0;
 618
 619	if (di_flags & XFS_DIFLAG_ANY) {
 620		if (di_flags & XFS_DIFLAG_REALTIME)
 621			flags |= FS_XFLAG_REALTIME;
 622		if (di_flags & XFS_DIFLAG_PREALLOC)
 623			flags |= FS_XFLAG_PREALLOC;
 624		if (di_flags & XFS_DIFLAG_IMMUTABLE)
 625			flags |= FS_XFLAG_IMMUTABLE;
 626		if (di_flags & XFS_DIFLAG_APPEND)
 627			flags |= FS_XFLAG_APPEND;
 628		if (di_flags & XFS_DIFLAG_SYNC)
 629			flags |= FS_XFLAG_SYNC;
 630		if (di_flags & XFS_DIFLAG_NOATIME)
 631			flags |= FS_XFLAG_NOATIME;
 632		if (di_flags & XFS_DIFLAG_NODUMP)
 633			flags |= FS_XFLAG_NODUMP;
 634		if (di_flags & XFS_DIFLAG_RTINHERIT)
 635			flags |= FS_XFLAG_RTINHERIT;
 636		if (di_flags & XFS_DIFLAG_PROJINHERIT)
 637			flags |= FS_XFLAG_PROJINHERIT;
 638		if (di_flags & XFS_DIFLAG_NOSYMLINKS)
 639			flags |= FS_XFLAG_NOSYMLINKS;
 640		if (di_flags & XFS_DIFLAG_EXTSIZE)
 641			flags |= FS_XFLAG_EXTSIZE;
 642		if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
 643			flags |= FS_XFLAG_EXTSZINHERIT;
 644		if (di_flags & XFS_DIFLAG_NODEFRAG)
 645			flags |= FS_XFLAG_NODEFRAG;
 646		if (di_flags & XFS_DIFLAG_FILESTREAM)
 647			flags |= FS_XFLAG_FILESTREAM;
 648	}
 649
 650	if (di_flags2 & XFS_DIFLAG2_ANY) {
 651		if (di_flags2 & XFS_DIFLAG2_DAX)
 652			flags |= FS_XFLAG_DAX;
 653		if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
 654			flags |= FS_XFLAG_COWEXTSIZE;
 655	}
 656
 657	if (has_attr)
 658		flags |= FS_XFLAG_HASATTR;
 659
 660	return flags;
 661}
 662
 663uint
 664xfs_ip2xflags(
 665	struct xfs_inode	*ip)
 666{
 667	struct xfs_icdinode	*dic = &ip->i_d;
 668
 669	return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip));
 
 
 
 
 
 
 
 
 
 670}
 671
 672/*
 673 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
 674 * is allowed, otherwise it has to be an exact match. If a CI match is found,
 675 * ci_name->name will point to a the actual name (caller must free) or
 676 * will be set to NULL if an exact match is found.
 677 */
 678int
 679xfs_lookup(
 680	xfs_inode_t		*dp,
 681	struct xfs_name		*name,
 682	xfs_inode_t		**ipp,
 683	struct xfs_name		*ci_name)
 684{
 685	xfs_ino_t		inum;
 686	int			error;
 687
 688	trace_xfs_lookup(dp, name);
 689
 690	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
 691		return -EIO;
 692
 693	error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
 
 
 
 694	if (error)
 695		goto out_unlock;
 696
 697	error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
 
 
 
 698	if (error)
 699		goto out_free_name;
 
 700
 701	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 702
 703out_free_name:
 704	if (ci_name)
 705		kmem_free(ci_name->name);
 706out_unlock:
 707	*ipp = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 708	return error;
 709}
 710
 711/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 712 * Allocate an inode on disk and return a copy of its in-core version.
 713 * The in-core inode is locked exclusively.  Set mode, nlink, and rdev
 714 * appropriately within the inode.  The uid and gid for the inode are
 715 * set according to the contents of the given cred structure.
 716 *
 717 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
 718 * has a free inode available, call xfs_iget() to obtain the in-core
 719 * version of the allocated inode.  Finally, fill in the inode and
 720 * log its initial contents.  In this case, ialloc_context would be
 721 * set to NULL.
 722 *
 723 * If xfs_dialloc() does not have an available inode, it will replenish
 724 * its supply by doing an allocation. Since we can only do one
 725 * allocation within a transaction without deadlocks, we must commit
 726 * the current transaction before returning the inode itself.
 727 * In this case, therefore, we will set ialloc_context and return.
 728 * The caller should then commit the current transaction, start a new
 729 * transaction, and call xfs_ialloc() again to actually get the inode.
 730 *
 731 * To ensure that some other process does not grab the inode that
 732 * was allocated during the first call to xfs_ialloc(), this routine
 733 * also returns the [locked] bp pointing to the head of the freelist
 734 * as ialloc_context.  The caller should hold this buffer across
 735 * the commit and pass it back into this routine on the second call.
 736 *
 737 * If we are allocating quota inodes, we do not have a parent inode
 738 * to attach to or associate with (i.e. pip == NULL) because they
 739 * are not linked into the directory structure - they are attached
 740 * directly to the superblock - and so have no parent.
 741 */
 742static int
 743xfs_ialloc(
 744	xfs_trans_t	*tp,
 745	xfs_inode_t	*pip,
 746	umode_t		mode,
 747	xfs_nlink_t	nlink,
 748	dev_t		rdev,
 749	prid_t		prid,
 
 750	xfs_buf_t	**ialloc_context,
 
 751	xfs_inode_t	**ipp)
 752{
 753	struct xfs_mount *mp = tp->t_mountp;
 754	xfs_ino_t	ino;
 755	xfs_inode_t	*ip;
 756	uint		flags;
 757	int		error;
 758	struct timespec64 tv;
 759	struct inode	*inode;
 760
 761	/*
 762	 * Call the space management code to pick
 763	 * the on-disk inode to be allocated.
 764	 */
 765	error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode,
 766			    ialloc_context, &ino);
 767	if (error)
 768		return error;
 769	if (*ialloc_context || ino == NULLFSINO) {
 770		*ipp = NULL;
 771		return 0;
 772	}
 773	ASSERT(*ialloc_context == NULL);
 774
 775	/*
 776	 * Protect against obviously corrupt allocation btree records. Later
 777	 * xfs_iget checks will catch re-allocation of other active in-memory
 778	 * and on-disk inodes. If we don't catch reallocating the parent inode
 779	 * here we will deadlock in xfs_iget() so we have to do these checks
 780	 * first.
 781	 */
 782	if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
 783		xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
 784		return -EFSCORRUPTED;
 785	}
 786
 787	/*
 788	 * Get the in-core inode with the lock held exclusively.
 789	 * This is because we're setting fields here we need
 790	 * to prevent others from looking at until we're done.
 791	 */
 792	error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
 793			 XFS_ILOCK_EXCL, &ip);
 794	if (error)
 795		return error;
 796	ASSERT(ip != NULL);
 797	inode = VFS_I(ip);
 
 
 
 
 
 
 
 
 798
 799	/*
 800	 * We always convert v1 inodes to v2 now - we only support filesystems
 801	 * with >= v2 inode capability, so there is no reason for ever leaving
 802	 * an inode in v1 format.
 
 803	 */
 804	if (ip->i_d.di_version == 1)
 
 805		ip->i_d.di_version = 2;
 
 
 
 
 
 806
 807	inode->i_mode = mode;
 808	set_nlink(inode, nlink);
 809	ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
 810	ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
 811	inode->i_rdev = rdev;
 812	xfs_set_projid(ip, prid);
 813
 814	if (pip && XFS_INHERIT_GID(pip)) {
 815		ip->i_d.di_gid = pip->i_d.di_gid;
 816		if ((VFS_I(pip)->i_mode & S_ISGID) && S_ISDIR(mode))
 817			inode->i_mode |= S_ISGID;
 
 818	}
 819
 820	/*
 821	 * If the group ID of the new file does not match the effective group
 822	 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
 823	 * (and only if the irix_sgid_inherit compatibility variable is set).
 824	 */
 825	if ((irix_sgid_inherit) &&
 826	    (inode->i_mode & S_ISGID) &&
 827	    (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid))))
 828		inode->i_mode &= ~S_ISGID;
 
 829
 830	ip->i_d.di_size = 0;
 831	ip->i_d.di_nextents = 0;
 832	ASSERT(ip->i_d.di_nblocks == 0);
 833
 834	tv = current_time(inode);
 835	inode->i_mtime = tv;
 836	inode->i_atime = tv;
 837	inode->i_ctime = tv;
 
 838
 
 
 
 839	ip->i_d.di_extsize = 0;
 840	ip->i_d.di_dmevmask = 0;
 841	ip->i_d.di_dmstate = 0;
 842	ip->i_d.di_flags = 0;
 843
 844	if (ip->i_d.di_version == 3) {
 845		inode_set_iversion(inode, 1);
 846		ip->i_d.di_flags2 = 0;
 847		ip->i_d.di_cowextsize = 0;
 848		ip->i_d.di_crtime.t_sec = (int32_t)tv.tv_sec;
 849		ip->i_d.di_crtime.t_nsec = (int32_t)tv.tv_nsec;
 850	}
 851
 852
 853	flags = XFS_ILOG_CORE;
 854	switch (mode & S_IFMT) {
 855	case S_IFIFO:
 856	case S_IFCHR:
 857	case S_IFBLK:
 858	case S_IFSOCK:
 859		ip->i_d.di_format = XFS_DINODE_FMT_DEV;
 
 860		ip->i_df.if_flags = 0;
 861		flags |= XFS_ILOG_DEV;
 862		break;
 863	case S_IFREG:
 
 
 
 
 
 
 
 864	case S_IFDIR:
 865		if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
 866			uint		di_flags = 0;
 867
 868			if (S_ISDIR(mode)) {
 869				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
 870					di_flags |= XFS_DIFLAG_RTINHERIT;
 871				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
 872					di_flags |= XFS_DIFLAG_EXTSZINHERIT;
 873					ip->i_d.di_extsize = pip->i_d.di_extsize;
 874				}
 875				if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
 876					di_flags |= XFS_DIFLAG_PROJINHERIT;
 877			} else if (S_ISREG(mode)) {
 878				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
 879					di_flags |= XFS_DIFLAG_REALTIME;
 880				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
 881					di_flags |= XFS_DIFLAG_EXTSIZE;
 882					ip->i_d.di_extsize = pip->i_d.di_extsize;
 883				}
 884			}
 885			if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
 886			    xfs_inherit_noatime)
 887				di_flags |= XFS_DIFLAG_NOATIME;
 888			if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
 889			    xfs_inherit_nodump)
 890				di_flags |= XFS_DIFLAG_NODUMP;
 891			if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
 892			    xfs_inherit_sync)
 893				di_flags |= XFS_DIFLAG_SYNC;
 894			if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
 895			    xfs_inherit_nosymlinks)
 896				di_flags |= XFS_DIFLAG_NOSYMLINKS;
 
 
 897			if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
 898			    xfs_inherit_nodefrag)
 899				di_flags |= XFS_DIFLAG_NODEFRAG;
 900			if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
 901				di_flags |= XFS_DIFLAG_FILESTREAM;
 902
 903			ip->i_d.di_flags |= di_flags;
 904		}
 905		if (pip &&
 906		    (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY) &&
 907		    pip->i_d.di_version == 3 &&
 908		    ip->i_d.di_version == 3) {
 909			uint64_t	di_flags2 = 0;
 910
 911			if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
 912				di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
 913				ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
 914			}
 915			if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
 916				di_flags2 |= XFS_DIFLAG2_DAX;
 917
 918			ip->i_d.di_flags2 |= di_flags2;
 919		}
 920		/* FALLTHROUGH */
 921	case S_IFLNK:
 922		ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
 923		ip->i_df.if_flags = XFS_IFEXTENTS;
 924		ip->i_df.if_bytes = 0;
 925		ip->i_df.if_u1.if_root = NULL;
 926		break;
 927	default:
 928		ASSERT(0);
 929	}
 930	/*
 931	 * Attribute fork settings for new inode.
 932	 */
 933	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
 934	ip->i_d.di_anextents = 0;
 935
 936	/*
 937	 * Log the new values stuffed into the inode.
 938	 */
 939	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 940	xfs_trans_log_inode(tp, ip, flags);
 941
 942	/* now that we have an i_mode we can setup the inode structure */
 943	xfs_setup_inode(ip);
 944
 945	*ipp = ip;
 946	return 0;
 947}
 948
 949/*
 950 * Allocates a new inode from disk and return a pointer to the
 951 * incore copy. This routine will internally commit the current
 952 * transaction and allocate a new one if the Space Manager needed
 953 * to do an allocation to replenish the inode free-list.
 954 *
 955 * This routine is designed to be called from xfs_create and
 956 * xfs_create_dir.
 957 *
 958 */
 959int
 960xfs_dir_ialloc(
 961	xfs_trans_t	**tpp,		/* input: current transaction;
 962					   output: may be a new transaction. */
 963	xfs_inode_t	*dp,		/* directory within whose allocate
 964					   the inode. */
 965	umode_t		mode,
 966	xfs_nlink_t	nlink,
 967	dev_t		rdev,
 968	prid_t		prid,		/* project id */
 969	xfs_inode_t	**ipp)		/* pointer to inode; it will be
 970					   locked. */
 971{
 972	xfs_trans_t	*tp;
 973	xfs_inode_t	*ip;
 974	xfs_buf_t	*ialloc_context = NULL;
 975	int		code;
 976	void		*dqinfo;
 977	uint		tflags;
 978
 979	tp = *tpp;
 980	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
 981
 982	/*
 983	 * xfs_ialloc will return a pointer to an incore inode if
 984	 * the Space Manager has an available inode on the free
 985	 * list. Otherwise, it will do an allocation and replenish
 986	 * the freelist.  Since we can only do one allocation per
 987	 * transaction without deadlocks, we will need to commit the
 988	 * current transaction and start a new one.  We will then
 989	 * need to call xfs_ialloc again to get the inode.
 990	 *
 991	 * If xfs_ialloc did an allocation to replenish the freelist,
 992	 * it returns the bp containing the head of the freelist as
 993	 * ialloc_context. We will hold a lock on it across the
 994	 * transaction commit so that no other process can steal
 995	 * the inode(s) that we've just allocated.
 996	 */
 997	code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, &ialloc_context,
 998			&ip);
 999
1000	/*
1001	 * Return an error if we were unable to allocate a new inode.
1002	 * This should only happen if we run out of space on disk or
1003	 * encounter a disk error.
1004	 */
1005	if (code) {
1006		*ipp = NULL;
1007		return code;
1008	}
1009	if (!ialloc_context && !ip) {
1010		*ipp = NULL;
1011		return -ENOSPC;
1012	}
1013
1014	/*
1015	 * If the AGI buffer is non-NULL, then we were unable to get an
1016	 * inode in one operation.  We need to commit the current
1017	 * transaction and call xfs_ialloc() again.  It is guaranteed
1018	 * to succeed the second time.
1019	 */
1020	if (ialloc_context) {
1021		/*
1022		 * Normally, xfs_trans_commit releases all the locks.
1023		 * We call bhold to hang on to the ialloc_context across
1024		 * the commit.  Holding this buffer prevents any other
1025		 * processes from doing any allocations in this
1026		 * allocation group.
1027		 */
1028		xfs_trans_bhold(tp, ialloc_context);
1029
1030		/*
1031		 * We want the quota changes to be associated with the next
1032		 * transaction, NOT this one. So, detach the dqinfo from this
1033		 * and attach it to the next transaction.
1034		 */
1035		dqinfo = NULL;
1036		tflags = 0;
1037		if (tp->t_dqinfo) {
1038			dqinfo = (void *)tp->t_dqinfo;
1039			tp->t_dqinfo = NULL;
1040			tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
1041			tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
1042		}
1043
1044		code = xfs_trans_roll(&tp);
1045
1046		/*
1047		 * Re-attach the quota info that we detached from prev trx.
1048		 */
1049		if (dqinfo) {
1050			tp->t_dqinfo = dqinfo;
1051			tp->t_flags |= tflags;
1052		}
1053
1054		if (code) {
1055			xfs_buf_relse(ialloc_context);
1056			*tpp = tp;
1057			*ipp = NULL;
1058			return code;
1059		}
1060		xfs_trans_bjoin(tp, ialloc_context);
1061
1062		/*
1063		 * Call ialloc again. Since we've locked out all
1064		 * other allocations in this allocation group,
1065		 * this call should always succeed.
1066		 */
1067		code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1068				  &ialloc_context, &ip);
1069
1070		/*
1071		 * If we get an error at this point, return to the caller
1072		 * so that the current transaction can be aborted.
1073		 */
1074		if (code) {
1075			*tpp = tp;
1076			*ipp = NULL;
1077			return code;
1078		}
1079		ASSERT(!ialloc_context && ip);
1080
1081	}
1082
1083	*ipp = ip;
1084	*tpp = tp;
1085
1086	return 0;
1087}
1088
1089/*
1090 * Decrement the link count on an inode & log the change.  If this causes the
1091 * link count to go to zero, move the inode to AGI unlinked list so that it can
1092 * be freed when the last active reference goes away via xfs_inactive().
1093 */
1094static int			/* error */
1095xfs_droplink(
1096	xfs_trans_t *tp,
1097	xfs_inode_t *ip)
1098{
1099	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1100
1101	drop_nlink(VFS_I(ip));
1102	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1103
1104	if (VFS_I(ip)->i_nlink)
1105		return 0;
1106
1107	return xfs_iunlink(tp, ip);
1108}
1109
1110/*
1111 * Increment the link count on an inode & log the change.
1112 */
1113static void
1114xfs_bumplink(
1115	xfs_trans_t *tp,
1116	xfs_inode_t *ip)
1117{
1118	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1119
1120	ASSERT(ip->i_d.di_version > 1);
1121	inc_nlink(VFS_I(ip));
1122	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1123}
1124
1125int
1126xfs_create(
1127	xfs_inode_t		*dp,
1128	struct xfs_name		*name,
1129	umode_t			mode,
1130	dev_t			rdev,
1131	xfs_inode_t		**ipp)
1132{
1133	int			is_dir = S_ISDIR(mode);
1134	struct xfs_mount	*mp = dp->i_mount;
1135	struct xfs_inode	*ip = NULL;
1136	struct xfs_trans	*tp = NULL;
1137	int			error;
1138	bool                    unlock_dp_on_error = false;
1139	prid_t			prid;
1140	struct xfs_dquot	*udqp = NULL;
1141	struct xfs_dquot	*gdqp = NULL;
1142	struct xfs_dquot	*pdqp = NULL;
1143	struct xfs_trans_res	*tres;
1144	uint			resblks;
1145
1146	trace_xfs_create(dp, name);
1147
1148	if (XFS_FORCED_SHUTDOWN(mp))
1149		return -EIO;
1150
1151	prid = xfs_get_initial_prid(dp);
1152
1153	/*
1154	 * Make sure that we have allocated dquot(s) on disk.
1155	 */
1156	error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1157					xfs_kgid_to_gid(current_fsgid()), prid,
1158					XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1159					&udqp, &gdqp, &pdqp);
1160	if (error)
1161		return error;
1162
1163	if (is_dir) {
1164		resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1165		tres = &M_RES(mp)->tr_mkdir;
1166	} else {
1167		resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1168		tres = &M_RES(mp)->tr_create;
1169	}
1170
1171	/*
1172	 * Initially assume that the file does not exist and
1173	 * reserve the resources for that case.  If that is not
1174	 * the case we'll drop the one we have and get a more
1175	 * appropriate transaction later.
1176	 */
1177	error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1178	if (error == -ENOSPC) {
1179		/* flush outstanding delalloc blocks and retry */
1180		xfs_flush_inodes(mp);
1181		error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1182	}
1183	if (error)
1184		goto out_release_inode;
1185
1186	xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1187	unlock_dp_on_error = true;
1188
1189	/*
1190	 * Reserve disk quota and the inode.
1191	 */
1192	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1193						pdqp, resblks, 1, 0);
1194	if (error)
1195		goto out_trans_cancel;
1196
1197	/*
1198	 * A newly created regular or special file just has one directory
1199	 * entry pointing to them, but a directory also the "." entry
1200	 * pointing to itself.
1201	 */
1202	error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, &ip);
1203	if (error)
1204		goto out_trans_cancel;
1205
1206	/*
1207	 * Now we join the directory inode to the transaction.  We do not do it
1208	 * earlier because xfs_dir_ialloc might commit the previous transaction
1209	 * (and release all the locks).  An error from here on will result in
1210	 * the transaction cancel unlocking dp so don't do it explicitly in the
1211	 * error path.
1212	 */
1213	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1214	unlock_dp_on_error = false;
1215
1216	error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1217				   resblks ?
1218					resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1219	if (error) {
1220		ASSERT(error != -ENOSPC);
1221		goto out_trans_cancel;
1222	}
1223	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1224	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1225
1226	if (is_dir) {
1227		error = xfs_dir_init(tp, ip, dp);
1228		if (error)
1229			goto out_trans_cancel;
1230
1231		xfs_bumplink(tp, dp);
1232	}
1233
1234	/*
1235	 * If this is a synchronous mount, make sure that the
1236	 * create transaction goes to disk before returning to
1237	 * the user.
1238	 */
1239	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1240		xfs_trans_set_sync(tp);
1241
1242	/*
1243	 * Attach the dquot(s) to the inodes and modify them incore.
1244	 * These ids of the inode couldn't have changed since the new
1245	 * inode has been locked ever since it was created.
1246	 */
1247	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1248
1249	error = xfs_trans_commit(tp);
1250	if (error)
1251		goto out_release_inode;
1252
1253	xfs_qm_dqrele(udqp);
1254	xfs_qm_dqrele(gdqp);
1255	xfs_qm_dqrele(pdqp);
1256
1257	*ipp = ip;
1258	return 0;
1259
1260 out_trans_cancel:
1261	xfs_trans_cancel(tp);
1262 out_release_inode:
1263	/*
1264	 * Wait until after the current transaction is aborted to finish the
1265	 * setup of the inode and release the inode.  This prevents recursive
1266	 * transactions and deadlocks from xfs_inactive.
1267	 */
1268	if (ip) {
1269		xfs_finish_inode_setup(ip);
1270		xfs_irele(ip);
1271	}
1272
1273	xfs_qm_dqrele(udqp);
1274	xfs_qm_dqrele(gdqp);
1275	xfs_qm_dqrele(pdqp);
1276
1277	if (unlock_dp_on_error)
1278		xfs_iunlock(dp, XFS_ILOCK_EXCL);
1279	return error;
1280}
1281
1282int
1283xfs_create_tmpfile(
1284	struct xfs_inode	*dp,
1285	umode_t			mode,
1286	struct xfs_inode	**ipp)
1287{
1288	struct xfs_mount	*mp = dp->i_mount;
1289	struct xfs_inode	*ip = NULL;
1290	struct xfs_trans	*tp = NULL;
1291	int			error;
1292	prid_t                  prid;
1293	struct xfs_dquot	*udqp = NULL;
1294	struct xfs_dquot	*gdqp = NULL;
1295	struct xfs_dquot	*pdqp = NULL;
1296	struct xfs_trans_res	*tres;
1297	uint			resblks;
1298
1299	if (XFS_FORCED_SHUTDOWN(mp))
1300		return -EIO;
1301
1302	prid = xfs_get_initial_prid(dp);
1303
1304	/*
1305	 * Make sure that we have allocated dquot(s) on disk.
1306	 */
1307	error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1308				xfs_kgid_to_gid(current_fsgid()), prid,
1309				XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1310				&udqp, &gdqp, &pdqp);
1311	if (error)
1312		return error;
1313
1314	resblks = XFS_IALLOC_SPACE_RES(mp);
1315	tres = &M_RES(mp)->tr_create_tmpfile;
1316
1317	error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1318	if (error)
1319		goto out_release_inode;
1320
1321	error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1322						pdqp, resblks, 1, 0);
1323	if (error)
1324		goto out_trans_cancel;
1325
1326	error = xfs_dir_ialloc(&tp, dp, mode, 0, 0, prid, &ip);
1327	if (error)
1328		goto out_trans_cancel;
1329
1330	if (mp->m_flags & XFS_MOUNT_WSYNC)
1331		xfs_trans_set_sync(tp);
1332
1333	/*
1334	 * Attach the dquot(s) to the inodes and modify them incore.
1335	 * These ids of the inode couldn't have changed since the new
1336	 * inode has been locked ever since it was created.
1337	 */
1338	xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1339
1340	error = xfs_iunlink(tp, ip);
1341	if (error)
1342		goto out_trans_cancel;
1343
1344	error = xfs_trans_commit(tp);
1345	if (error)
1346		goto out_release_inode;
1347
1348	xfs_qm_dqrele(udqp);
1349	xfs_qm_dqrele(gdqp);
1350	xfs_qm_dqrele(pdqp);
1351
1352	*ipp = ip;
1353	return 0;
1354
1355 out_trans_cancel:
1356	xfs_trans_cancel(tp);
1357 out_release_inode:
1358	/*
1359	 * Wait until after the current transaction is aborted to finish the
1360	 * setup of the inode and release the inode.  This prevents recursive
1361	 * transactions and deadlocks from xfs_inactive.
1362	 */
1363	if (ip) {
1364		xfs_finish_inode_setup(ip);
1365		xfs_irele(ip);
1366	}
1367
1368	xfs_qm_dqrele(udqp);
1369	xfs_qm_dqrele(gdqp);
1370	xfs_qm_dqrele(pdqp);
1371
1372	return error;
1373}
1374
1375int
1376xfs_link(
1377	xfs_inode_t		*tdp,
1378	xfs_inode_t		*sip,
1379	struct xfs_name		*target_name)
1380{
1381	xfs_mount_t		*mp = tdp->i_mount;
1382	xfs_trans_t		*tp;
1383	int			error;
1384	int			resblks;
1385
1386	trace_xfs_link(tdp, target_name);
1387
1388	ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1389
1390	if (XFS_FORCED_SHUTDOWN(mp))
1391		return -EIO;
1392
1393	error = xfs_qm_dqattach(sip);
1394	if (error)
1395		goto std_return;
1396
1397	error = xfs_qm_dqattach(tdp);
1398	if (error)
1399		goto std_return;
1400
1401	resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1402	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1403	if (error == -ENOSPC) {
1404		resblks = 0;
1405		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
1406	}
1407	if (error)
1408		goto std_return;
1409
1410	xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL);
1411
1412	xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1413	xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1414
1415	/*
1416	 * If we are using project inheritance, we only allow hard link
1417	 * creation in our tree when the project IDs are the same; else
1418	 * the tree quota mechanism could be circumvented.
1419	 */
1420	if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1421		     (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1422		error = -EXDEV;
1423		goto error_return;
1424	}
1425
1426	if (!resblks) {
1427		error = xfs_dir_canenter(tp, tdp, target_name);
1428		if (error)
1429			goto error_return;
1430	}
1431
1432	/*
1433	 * Handle initial link state of O_TMPFILE inode
1434	 */
1435	if (VFS_I(sip)->i_nlink == 0) {
1436		error = xfs_iunlink_remove(tp, sip);
1437		if (error)
1438			goto error_return;
1439	}
1440
1441	error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1442				   resblks);
1443	if (error)
1444		goto error_return;
1445	xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1446	xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1447
1448	xfs_bumplink(tp, sip);
1449
1450	/*
1451	 * If this is a synchronous mount, make sure that the
1452	 * link transaction goes to disk before returning to
1453	 * the user.
1454	 */
1455	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1456		xfs_trans_set_sync(tp);
1457
1458	return xfs_trans_commit(tp);
1459
1460 error_return:
1461	xfs_trans_cancel(tp);
1462 std_return:
1463	return error;
1464}
1465
1466/* Clear the reflink flag and the cowblocks tag if possible. */
1467static void
1468xfs_itruncate_clear_reflink_flags(
1469	struct xfs_inode	*ip)
1470{
1471	struct xfs_ifork	*dfork;
1472	struct xfs_ifork	*cfork;
1473
1474	if (!xfs_is_reflink_inode(ip))
1475		return;
1476	dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
1477	cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1478	if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1479		ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1480	if (cfork->if_bytes == 0)
1481		xfs_inode_clear_cowblocks_tag(ip);
1482}
1483
1484/*
1485 * Free up the underlying blocks past new_size.  The new size must be smaller
1486 * than the current size.  This routine can be used both for the attribute and
1487 * data fork, and does not modify the inode size, which is left to the caller.
1488 *
1489 * The transaction passed to this routine must have made a permanent log
1490 * reservation of at least XFS_ITRUNCATE_LOG_RES.  This routine may commit the
1491 * given transaction and start new ones, so make sure everything involved in
1492 * the transaction is tidy before calling here.  Some transaction will be
1493 * returned to the caller to be committed.  The incoming transaction must
1494 * already include the inode, and both inode locks must be held exclusively.
1495 * The inode must also be "held" within the transaction.  On return the inode
1496 * will be "held" within the returned transaction.  This routine does NOT
1497 * require any disk space to be reserved for it within the transaction.
1498 *
1499 * If we get an error, we must return with the inode locked and linked into the
1500 * current transaction. This keeps things simple for the higher level code,
1501 * because it always knows that the inode is locked and held in the transaction
1502 * that returns to it whether errors occur or not.  We don't mark the inode
1503 * dirty on error so that transactions can be easily aborted if possible.
1504 */
1505int
1506xfs_itruncate_extents_flags(
1507	struct xfs_trans	**tpp,
1508	struct xfs_inode	*ip,
1509	int			whichfork,
1510	xfs_fsize_t		new_size,
1511	int			flags)
1512{
1513	struct xfs_mount	*mp = ip->i_mount;
1514	struct xfs_trans	*tp = *tpp;
 
 
 
1515	xfs_fileoff_t		first_unmap_block;
1516	xfs_fileoff_t		last_block;
1517	xfs_filblks_t		unmap_len;
 
1518	int			error = 0;
1519	int			done = 0;
1520
1521	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1522	ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1523	       xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1524	ASSERT(new_size <= XFS_ISIZE(ip));
1525	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1526	ASSERT(ip->i_itemp != NULL);
1527	ASSERT(ip->i_itemp->ili_lock_flags == 0);
1528	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1529
1530	trace_xfs_itruncate_extents_start(ip, new_size);
1531
1532	flags |= xfs_bmapi_aflag(whichfork);
1533
1534	/*
1535	 * Since it is possible for space to become allocated beyond
1536	 * the end of the file (in a crash where the space is allocated
1537	 * but the inode size is not yet updated), simply remove any
1538	 * blocks which show up between the new EOF and the maximum
1539	 * possible file size.  If the first block to be removed is
1540	 * beyond the maximum file size (ie it is the same as last_block),
1541	 * then there is nothing to do.
1542	 */
1543	first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1544	last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1545	if (first_unmap_block == last_block)
1546		return 0;
1547
1548	ASSERT(first_unmap_block < last_block);
1549	unmap_len = last_block - first_unmap_block + 1;
1550	while (!done) {
1551		ASSERT(tp->t_firstblock == NULLFSBLOCK);
1552		error = xfs_bunmapi(tp, ip, first_unmap_block, unmap_len, flags,
1553				    XFS_ITRUNC_MAX_EXTENTS, &done);
 
 
 
 
1554		if (error)
1555			goto out;
1556
1557		/*
1558		 * Duplicate the transaction that has the permanent
1559		 * reservation and commit the old transaction.
1560		 */
1561		error = xfs_defer_finish(&tp);
 
 
1562		if (error)
1563			goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1564
1565		error = xfs_trans_roll_inode(&tp, ip);
1566		if (error)
1567			goto out;
1568	}
1569
1570	if (whichfork == XFS_DATA_FORK) {
1571		/* Remove all pending CoW reservations. */
1572		error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1573				first_unmap_block, last_block, true);
 
 
 
 
 
1574		if (error)
1575			goto out;
1576
1577		xfs_itruncate_clear_reflink_flags(ip);
1578	}
1579
1580	/*
1581	 * Always re-log the inode so that our permanent transaction can keep
1582	 * on rolling it forward in the log.
1583	 */
1584	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1585
1586	trace_xfs_itruncate_extents_end(ip, new_size);
1587
1588out:
1589	*tpp = tp;
1590	return error;
1591}
1592
1593int
1594xfs_release(
1595	xfs_inode_t	*ip)
1596{
1597	xfs_mount_t	*mp = ip->i_mount;
1598	int		error;
1599
1600	if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1601		return 0;
1602
1603	/* If this is a read-only mount, don't do this (would generate I/O) */
1604	if (mp->m_flags & XFS_MOUNT_RDONLY)
1605		return 0;
1606
1607	if (!XFS_FORCED_SHUTDOWN(mp)) {
1608		int truncated;
1609
1610		/*
1611		 * If we previously truncated this file and removed old data
1612		 * in the process, we want to initiate "early" writeout on
1613		 * the last close.  This is an attempt to combat the notorious
1614		 * NULL files problem which is particularly noticeable from a
1615		 * truncate down, buffered (re-)write (delalloc), followed by
1616		 * a crash.  What we are effectively doing here is
1617		 * significantly reducing the time window where we'd otherwise
1618		 * be exposed to that problem.
1619		 */
1620		truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1621		if (truncated) {
1622			xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1623			if (ip->i_delayed_blks > 0) {
1624				error = filemap_flush(VFS_I(ip)->i_mapping);
1625				if (error)
1626					return error;
1627			}
1628		}
1629	}
1630
1631	if (VFS_I(ip)->i_nlink == 0)
1632		return 0;
1633
1634	if (xfs_can_free_eofblocks(ip, false)) {
1635
1636		/*
1637		 * Check if the inode is being opened, written and closed
1638		 * frequently and we have delayed allocation blocks outstanding
1639		 * (e.g. streaming writes from the NFS server), truncating the
1640		 * blocks past EOF will cause fragmentation to occur.
1641		 *
1642		 * In this case don't do the truncation, but we have to be
1643		 * careful how we detect this case. Blocks beyond EOF show up as
1644		 * i_delayed_blks even when the inode is clean, so we need to
1645		 * truncate them away first before checking for a dirty release.
1646		 * Hence on the first dirty close we will still remove the
1647		 * speculative allocation, but after that we will leave it in
1648		 * place.
1649		 */
1650		if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1651			return 0;
1652		/*
1653		 * If we can't get the iolock just skip truncating the blocks
1654		 * past EOF because we could deadlock with the mmap_sem
1655		 * otherwise. We'll get another chance to drop them once the
1656		 * last reference to the inode is dropped, so we'll never leak
1657		 * blocks permanently.
1658		 */
1659		if (xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1660			error = xfs_free_eofblocks(ip);
1661			xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1662			if (error)
1663				return error;
1664		}
1665
1666		/* delalloc blocks after truncation means it really is dirty */
1667		if (ip->i_delayed_blks)
1668			xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1669	}
1670	return 0;
1671}
1672
1673/*
1674 * xfs_inactive_truncate
1675 *
1676 * Called to perform a truncate when an inode becomes unlinked.
1677 */
1678STATIC int
1679xfs_inactive_truncate(
1680	struct xfs_inode *ip)
1681{
1682	struct xfs_mount	*mp = ip->i_mount;
1683	struct xfs_trans	*tp;
1684	int			error;
1685
1686	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1687	if (error) {
1688		ASSERT(XFS_FORCED_SHUTDOWN(mp));
1689		return error;
1690	}
1691	xfs_ilock(ip, XFS_ILOCK_EXCL);
1692	xfs_trans_ijoin(tp, ip, 0);
1693
1694	/*
1695	 * Log the inode size first to prevent stale data exposure in the event
1696	 * of a system crash before the truncate completes. See the related
1697	 * comment in xfs_vn_setattr_size() for details.
1698	 */
1699	ip->i_d.di_size = 0;
1700	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1701
1702	error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1703	if (error)
1704		goto error_trans_cancel;
1705
1706	ASSERT(ip->i_d.di_nextents == 0);
1707
1708	error = xfs_trans_commit(tp);
1709	if (error)
1710		goto error_unlock;
1711
1712	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1713	return 0;
1714
1715error_trans_cancel:
1716	xfs_trans_cancel(tp);
1717error_unlock:
1718	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1719	return error;
1720}
1721
1722/*
1723 * xfs_inactive_ifree()
1724 *
1725 * Perform the inode free when an inode is unlinked.
1726 */
1727STATIC int
1728xfs_inactive_ifree(
1729	struct xfs_inode *ip)
 
1730{
1731	struct xfs_mount	*mp = ip->i_mount;
1732	struct xfs_trans	*tp;
1733	int			error;
1734
1735	/*
1736	 * We try to use a per-AG reservation for any block needed by the finobt
1737	 * tree, but as the finobt feature predates the per-AG reservation
1738	 * support a degraded file system might not have enough space for the
1739	 * reservation at mount time.  In that case try to dip into the reserved
1740	 * pool and pray.
1741	 *
1742	 * Send a warning if the reservation does happen to fail, as the inode
1743	 * now remains allocated and sits on the unlinked list until the fs is
1744	 * repaired.
1745	 */
1746	if (unlikely(mp->m_finobt_nores)) {
1747		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1748				XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1749				&tp);
1750	} else {
1751		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1752	}
1753	if (error) {
1754		if (error == -ENOSPC) {
1755			xfs_warn_ratelimited(mp,
1756			"Failed to remove inode(s) from unlinked list. "
1757			"Please free space, unmount and run xfs_repair.");
1758		} else {
1759			ASSERT(XFS_FORCED_SHUTDOWN(mp));
1760		}
1761		return error;
1762	}
1763
1764	xfs_ilock(ip, XFS_ILOCK_EXCL);
1765	xfs_trans_ijoin(tp, ip, 0);
1766
1767	error = xfs_ifree(tp, ip);
1768	if (error) {
1769		/*
1770		 * If we fail to free the inode, shut down.  The cancel
1771		 * might do that, we need to make sure.  Otherwise the
1772		 * inode might be lost for a long time or forever.
1773		 */
1774		if (!XFS_FORCED_SHUTDOWN(mp)) {
1775			xfs_notice(mp, "%s: xfs_ifree returned error %d",
1776				__func__, error);
1777			xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1778		}
1779		xfs_trans_cancel(tp);
1780		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1781		return error;
1782	}
1783
1784	/*
1785	 * Credit the quota account(s). The inode is gone.
1786	 */
1787	xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1788
1789	/*
1790	 * Just ignore errors at this point.  There is nothing we can do except
1791	 * to try to keep going. Make sure it's not a silent error.
1792	 */
1793	error = xfs_trans_commit(tp);
1794	if (error)
1795		xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1796			__func__, error);
1797
1798	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1799	return 0;
1800}
1801
1802/*
1803 * xfs_inactive
1804 *
1805 * This is called when the vnode reference count for the vnode
1806 * goes to zero.  If the file has been unlinked, then it must
1807 * now be truncated.  Also, we clear all of the read-ahead state
1808 * kept for the inode here since the file is now closed.
1809 */
1810void
1811xfs_inactive(
1812	xfs_inode_t	*ip)
1813{
1814	struct xfs_mount	*mp;
1815	int			error;
1816	int			truncate = 0;
1817
1818	/*
1819	 * If the inode is already free, then there can be nothing
1820	 * to clean up here.
1821	 */
1822	if (VFS_I(ip)->i_mode == 0) {
1823		ASSERT(ip->i_df.if_broot_bytes == 0);
1824		return;
1825	}
1826
1827	mp = ip->i_mount;
1828	ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1829
1830	/* If this is a read-only mount, don't do this (would generate I/O) */
1831	if (mp->m_flags & XFS_MOUNT_RDONLY)
1832		return;
1833
1834	/* Try to clean out the cow blocks if there are any. */
1835	if (xfs_inode_has_cow_data(ip))
1836		xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1837
1838	if (VFS_I(ip)->i_nlink != 0) {
1839		/*
1840		 * force is true because we are evicting an inode from the
1841		 * cache. Post-eof blocks must be freed, lest we end up with
1842		 * broken free space accounting.
1843		 *
1844		 * Note: don't bother with iolock here since lockdep complains
1845		 * about acquiring it in reclaim context. We have the only
1846		 * reference to the inode at this point anyways.
1847		 */
1848		if (xfs_can_free_eofblocks(ip, true))
1849			xfs_free_eofblocks(ip);
1850
1851		return;
1852	}
1853
1854	if (S_ISREG(VFS_I(ip)->i_mode) &&
1855	    (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1856	     ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1857		truncate = 1;
1858
1859	error = xfs_qm_dqattach(ip);
1860	if (error)
1861		return;
1862
1863	if (S_ISLNK(VFS_I(ip)->i_mode))
1864		error = xfs_inactive_symlink(ip);
1865	else if (truncate)
1866		error = xfs_inactive_truncate(ip);
1867	if (error)
1868		return;
1869
1870	/*
1871	 * If there are attributes associated with the file then blow them away
1872	 * now.  The code calls a routine that recursively deconstructs the
1873	 * attribute fork. If also blows away the in-core attribute fork.
1874	 */
1875	if (XFS_IFORK_Q(ip)) {
1876		error = xfs_attr_inactive(ip);
1877		if (error)
1878			return;
1879	}
1880
1881	ASSERT(!ip->i_afp);
1882	ASSERT(ip->i_d.di_anextents == 0);
1883	ASSERT(ip->i_d.di_forkoff == 0);
1884
1885	/*
1886	 * Free the inode.
1887	 */
1888	error = xfs_inactive_ifree(ip);
1889	if (error)
1890		return;
1891
1892	/*
1893	 * Release the dquots held by inode, if any.
1894	 */
1895	xfs_qm_dqdetach(ip);
1896}
1897
1898/*
1899 * In-Core Unlinked List Lookups
1900 * =============================
1901 *
1902 * Every inode is supposed to be reachable from some other piece of metadata
1903 * with the exception of the root directory.  Inodes with a connection to a
1904 * file descriptor but not linked from anywhere in the on-disk directory tree
1905 * are collectively known as unlinked inodes, though the filesystem itself
1906 * maintains links to these inodes so that on-disk metadata are consistent.
1907 *
1908 * XFS implements a per-AG on-disk hash table of unlinked inodes.  The AGI
1909 * header contains a number of buckets that point to an inode, and each inode
1910 * record has a pointer to the next inode in the hash chain.  This
1911 * singly-linked list causes scaling problems in the iunlink remove function
1912 * because we must walk that list to find the inode that points to the inode
1913 * being removed from the unlinked hash bucket list.
1914 *
1915 * What if we modelled the unlinked list as a collection of records capturing
1916 * "X.next_unlinked = Y" relations?  If we indexed those records on Y, we'd
1917 * have a fast way to look up unlinked list predecessors, which avoids the
1918 * slow list walk.  That's exactly what we do here (in-core) with a per-AG
1919 * rhashtable.
1920 *
1921 * Because this is a backref cache, we ignore operational failures since the
1922 * iunlink code can fall back to the slow bucket walk.  The only errors that
1923 * should bubble out are for obviously incorrect situations.
1924 *
1925 * All users of the backref cache MUST hold the AGI buffer lock to serialize
1926 * access or have otherwise provided for concurrency control.
1927 */
1928
1929/* Capture a "X.next_unlinked = Y" relationship. */
1930struct xfs_iunlink {
1931	struct rhash_head	iu_rhash_head;
1932	xfs_agino_t		iu_agino;		/* X */
1933	xfs_agino_t		iu_next_unlinked;	/* Y */
1934};
1935
1936/* Unlinked list predecessor lookup hashtable construction */
1937static int
1938xfs_iunlink_obj_cmpfn(
1939	struct rhashtable_compare_arg	*arg,
1940	const void			*obj)
1941{
1942	const xfs_agino_t		*key = arg->key;
1943	const struct xfs_iunlink	*iu = obj;
1944
1945	if (iu->iu_next_unlinked != *key)
1946		return 1;
1947	return 0;
1948}
1949
1950static const struct rhashtable_params xfs_iunlink_hash_params = {
1951	.min_size		= XFS_AGI_UNLINKED_BUCKETS,
1952	.key_len		= sizeof(xfs_agino_t),
1953	.key_offset		= offsetof(struct xfs_iunlink,
1954					   iu_next_unlinked),
1955	.head_offset		= offsetof(struct xfs_iunlink, iu_rhash_head),
1956	.automatic_shrinking	= true,
1957	.obj_cmpfn		= xfs_iunlink_obj_cmpfn,
1958};
1959
1960/*
1961 * Return X, where X.next_unlinked == @agino.  Returns NULLAGINO if no such
1962 * relation is found.
1963 */
1964static xfs_agino_t
1965xfs_iunlink_lookup_backref(
1966	struct xfs_perag	*pag,
1967	xfs_agino_t		agino)
1968{
1969	struct xfs_iunlink	*iu;
1970
1971	iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
1972			xfs_iunlink_hash_params);
1973	return iu ? iu->iu_agino : NULLAGINO;
1974}
1975
1976/*
1977 * Take ownership of an iunlink cache entry and insert it into the hash table.
1978 * If successful, the entry will be owned by the cache; if not, it is freed.
1979 * Either way, the caller does not own @iu after this call.
1980 */
1981static int
1982xfs_iunlink_insert_backref(
1983	struct xfs_perag	*pag,
1984	struct xfs_iunlink	*iu)
1985{
1986	int			error;
1987
1988	error = rhashtable_insert_fast(&pag->pagi_unlinked_hash,
1989			&iu->iu_rhash_head, xfs_iunlink_hash_params);
1990	/*
1991	 * Fail loudly if there already was an entry because that's a sign of
1992	 * corruption of in-memory data.  Also fail loudly if we see an error
1993	 * code we didn't anticipate from the rhashtable code.  Currently we
1994	 * only anticipate ENOMEM.
1995	 */
1996	if (error) {
1997		WARN(error != -ENOMEM, "iunlink cache insert error %d", error);
1998		kmem_free(iu);
1999	}
2000	/*
2001	 * Absorb any runtime errors that aren't a result of corruption because
2002	 * this is a cache and we can always fall back to bucket list scanning.
2003	 */
2004	if (error != 0 && error != -EEXIST)
2005		error = 0;
2006	return error;
2007}
2008
2009/* Remember that @prev_agino.next_unlinked = @this_agino. */
2010static int
2011xfs_iunlink_add_backref(
2012	struct xfs_perag	*pag,
2013	xfs_agino_t		prev_agino,
2014	xfs_agino_t		this_agino)
2015{
2016	struct xfs_iunlink	*iu;
2017
2018	if (XFS_TEST_ERROR(false, pag->pag_mount, XFS_ERRTAG_IUNLINK_FALLBACK))
2019		return 0;
2020
2021	iu = kmem_zalloc(sizeof(*iu), KM_NOFS);
2022	iu->iu_agino = prev_agino;
2023	iu->iu_next_unlinked = this_agino;
2024
2025	return xfs_iunlink_insert_backref(pag, iu);
2026}
2027
2028/*
2029 * Replace X.next_unlinked = @agino with X.next_unlinked = @next_unlinked.
2030 * If @next_unlinked is NULLAGINO, we drop the backref and exit.  If there
2031 * wasn't any such entry then we don't bother.
2032 */
2033static int
2034xfs_iunlink_change_backref(
2035	struct xfs_perag	*pag,
2036	xfs_agino_t		agino,
2037	xfs_agino_t		next_unlinked)
2038{
2039	struct xfs_iunlink	*iu;
2040	int			error;
2041
2042	/* Look up the old entry; if there wasn't one then exit. */
2043	iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
2044			xfs_iunlink_hash_params);
2045	if (!iu)
2046		return 0;
2047
2048	/*
2049	 * Remove the entry.  This shouldn't ever return an error, but if we
2050	 * couldn't remove the old entry we don't want to add it again to the
2051	 * hash table, and if the entry disappeared on us then someone's
2052	 * violated the locking rules and we need to fail loudly.  Either way
2053	 * we cannot remove the inode because internal state is or would have
2054	 * been corrupt.
2055	 */
2056	error = rhashtable_remove_fast(&pag->pagi_unlinked_hash,
2057			&iu->iu_rhash_head, xfs_iunlink_hash_params);
2058	if (error)
2059		return error;
2060
2061	/* If there is no new next entry just free our item and return. */
2062	if (next_unlinked == NULLAGINO) {
2063		kmem_free(iu);
2064		return 0;
2065	}
2066
2067	/* Update the entry and re-add it to the hash table. */
2068	iu->iu_next_unlinked = next_unlinked;
2069	return xfs_iunlink_insert_backref(pag, iu);
2070}
2071
2072/* Set up the in-core predecessor structures. */
2073int
2074xfs_iunlink_init(
2075	struct xfs_perag	*pag)
2076{
2077	return rhashtable_init(&pag->pagi_unlinked_hash,
2078			&xfs_iunlink_hash_params);
2079}
2080
2081/* Free the in-core predecessor structures. */
2082static void
2083xfs_iunlink_free_item(
2084	void			*ptr,
2085	void			*arg)
2086{
2087	struct xfs_iunlink	*iu = ptr;
2088	bool			*freed_anything = arg;
2089
2090	*freed_anything = true;
2091	kmem_free(iu);
2092}
2093
2094void
2095xfs_iunlink_destroy(
2096	struct xfs_perag	*pag)
2097{
2098	bool			freed_anything = false;
2099
2100	rhashtable_free_and_destroy(&pag->pagi_unlinked_hash,
2101			xfs_iunlink_free_item, &freed_anything);
2102
2103	ASSERT(freed_anything == false || XFS_FORCED_SHUTDOWN(pag->pag_mount));
2104}
2105
2106/*
2107 * Point the AGI unlinked bucket at an inode and log the results.  The caller
2108 * is responsible for validating the old value.
2109 */
2110STATIC int
2111xfs_iunlink_update_bucket(
2112	struct xfs_trans	*tp,
2113	xfs_agnumber_t		agno,
2114	struct xfs_buf		*agibp,
2115	unsigned int		bucket_index,
2116	xfs_agino_t		new_agino)
2117{
2118	struct xfs_agi		*agi = XFS_BUF_TO_AGI(agibp);
2119	xfs_agino_t		old_value;
2120	int			offset;
2121
2122	ASSERT(xfs_verify_agino_or_null(tp->t_mountp, agno, new_agino));
2123
2124	old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2125	trace_xfs_iunlink_update_bucket(tp->t_mountp, agno, bucket_index,
2126			old_value, new_agino);
2127
2128	/*
2129	 * We should never find the head of the list already set to the value
2130	 * passed in because either we're adding or removing ourselves from the
2131	 * head of the list.
2132	 */
2133	if (old_value == new_agino)
2134		return -EFSCORRUPTED;
2135
2136	agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino);
2137	offset = offsetof(struct xfs_agi, agi_unlinked) +
2138			(sizeof(xfs_agino_t) * bucket_index);
2139	xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1);
2140	return 0;
2141}
2142
2143/* Set an on-disk inode's next_unlinked pointer. */
2144STATIC void
2145xfs_iunlink_update_dinode(
2146	struct xfs_trans	*tp,
2147	xfs_agnumber_t		agno,
2148	xfs_agino_t		agino,
2149	struct xfs_buf		*ibp,
2150	struct xfs_dinode	*dip,
2151	struct xfs_imap		*imap,
2152	xfs_agino_t		next_agino)
2153{
2154	struct xfs_mount	*mp = tp->t_mountp;
2155	int			offset;
2156
2157	ASSERT(xfs_verify_agino_or_null(mp, agno, next_agino));
2158
2159	trace_xfs_iunlink_update_dinode(mp, agno, agino,
2160			be32_to_cpu(dip->di_next_unlinked), next_agino);
2161
2162	dip->di_next_unlinked = cpu_to_be32(next_agino);
2163	offset = imap->im_boffset +
2164			offsetof(struct xfs_dinode, di_next_unlinked);
2165
2166	/* need to recalc the inode CRC if appropriate */
2167	xfs_dinode_calc_crc(mp, dip);
2168	xfs_trans_inode_buf(tp, ibp);
2169	xfs_trans_log_buf(tp, ibp, offset, offset + sizeof(xfs_agino_t) - 1);
2170	xfs_inobp_check(mp, ibp);
2171}
2172
2173/* Set an in-core inode's unlinked pointer and return the old value. */
2174STATIC int
2175xfs_iunlink_update_inode(
2176	struct xfs_trans	*tp,
2177	struct xfs_inode	*ip,
2178	xfs_agnumber_t		agno,
2179	xfs_agino_t		next_agino,
2180	xfs_agino_t		*old_next_agino)
2181{
2182	struct xfs_mount	*mp = tp->t_mountp;
2183	struct xfs_dinode	*dip;
2184	struct xfs_buf		*ibp;
2185	xfs_agino_t		old_value;
2186	int			error;
2187
2188	ASSERT(xfs_verify_agino_or_null(mp, agno, next_agino));
2189
2190	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp, 0, 0);
2191	if (error)
2192		return error;
 
 
 
2193
2194	/* Make sure the old pointer isn't garbage. */
2195	old_value = be32_to_cpu(dip->di_next_unlinked);
2196	if (!xfs_verify_agino_or_null(mp, agno, old_value)) {
2197		error = -EFSCORRUPTED;
2198		goto out;
2199	}
2200
2201	/*
2202	 * Since we're updating a linked list, we should never find that the
2203	 * current pointer is the same as the new value, unless we're
2204	 * terminating the list.
2205	 */
2206	*old_next_agino = old_value;
2207	if (old_value == next_agino) {
2208		if (next_agino != NULLAGINO)
2209			error = -EFSCORRUPTED;
2210		goto out;
2211	}
2212
2213	/* Ok, update the new pointer. */
2214	xfs_iunlink_update_dinode(tp, agno, XFS_INO_TO_AGINO(mp, ip->i_ino),
2215			ibp, dip, &ip->i_imap, next_agino);
2216	return 0;
2217out:
2218	xfs_trans_brelse(tp, ibp);
2219	return error;
2220}
2221
2222/*
2223 * This is called when the inode's link count has gone to 0 or we are creating
2224 * a tmpfile via O_TMPFILE.  The inode @ip must have nlink == 0.
2225 *
2226 * We place the on-disk inode on a list in the AGI.  It will be pulled from this
2227 * list when the inode is freed.
2228 */
2229STATIC int
2230xfs_iunlink(
2231	struct xfs_trans	*tp,
2232	struct xfs_inode	*ip)
2233{
2234	struct xfs_mount	*mp = tp->t_mountp;
2235	struct xfs_agi		*agi;
2236	struct xfs_buf		*agibp;
2237	xfs_agino_t		next_agino;
2238	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2239	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2240	short			bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2241	int			error;
2242
2243	ASSERT(VFS_I(ip)->i_nlink == 0);
2244	ASSERT(VFS_I(ip)->i_mode != 0);
2245	trace_xfs_iunlink(ip);
2246
2247	/* Get the agi buffer first.  It ensures lock ordering on the list. */
2248	error = xfs_read_agi(mp, tp, agno, &agibp);
2249	if (error)
2250		return error;
 
2251	agi = XFS_BUF_TO_AGI(agibp);
2252
2253	/*
2254	 * Get the index into the agi hash table for the list this inode will
2255	 * go on.  Make sure the pointer isn't garbage and that this inode
2256	 * isn't already on the list.
2257	 */
2258	next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2259	if (next_agino == agino ||
2260	    !xfs_verify_agino_or_null(mp, agno, next_agino))
2261		return -EFSCORRUPTED;
2262
2263	if (next_agino != NULLAGINO) {
2264		struct xfs_perag	*pag;
2265		xfs_agino_t		old_agino;
2266
2267		/*
2268		 * There is already another inode in the bucket, so point this
2269		 * inode to the current head of the list.
2270		 */
2271		error = xfs_iunlink_update_inode(tp, ip, agno, next_agino,
2272				&old_agino);
2273		if (error)
 
 
 
2274			return error;
2275		ASSERT(old_agino == NULLAGINO);
2276
 
 
 
 
 
 
 
 
 
 
 
 
2277		/*
2278		 * agino has been unlinked, add a backref from the next inode
2279		 * back to agino.
2280		 */
2281		pag = xfs_perag_get(mp, agno);
2282		error = xfs_iunlink_add_backref(pag, agino, next_agino);
2283		xfs_perag_put(pag);
2284		if (error)
2285			return error;
2286	}
2287
2288	/* Point the head of the list to point to this inode. */
2289	return xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index, agino);
2290}
2291
2292/* Return the imap, dinode pointer, and buffer for an inode. */
2293STATIC int
2294xfs_iunlink_map_ino(
2295	struct xfs_trans	*tp,
2296	xfs_agnumber_t		agno,
2297	xfs_agino_t		agino,
2298	struct xfs_imap		*imap,
2299	struct xfs_dinode	**dipp,
2300	struct xfs_buf		**bpp)
2301{
2302	struct xfs_mount	*mp = tp->t_mountp;
2303	int			error;
2304
2305	imap->im_blkno = 0;
2306	error = xfs_imap(mp, tp, XFS_AGINO_TO_INO(mp, agno, agino), imap, 0);
2307	if (error) {
2308		xfs_warn(mp, "%s: xfs_imap returned error %d.",
2309				__func__, error);
2310		return error;
2311	}
2312
2313	error = xfs_imap_to_bp(mp, tp, imap, dipp, bpp, 0, 0);
2314	if (error) {
2315		xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2316				__func__, error);
2317		return error;
2318	}
2319
2320	return 0;
2321}
2322
2323/*
2324 * Walk the unlinked chain from @head_agino until we find the inode that
2325 * points to @target_agino.  Return the inode number, map, dinode pointer,
2326 * and inode cluster buffer of that inode as @agino, @imap, @dipp, and @bpp.
2327 *
2328 * @tp, @pag, @head_agino, and @target_agino are input parameters.
2329 * @agino, @imap, @dipp, and @bpp are all output parameters.
2330 *
2331 * Do not call this function if @target_agino is the head of the list.
2332 */
2333STATIC int
2334xfs_iunlink_map_prev(
2335	struct xfs_trans	*tp,
2336	xfs_agnumber_t		agno,
2337	xfs_agino_t		head_agino,
2338	xfs_agino_t		target_agino,
2339	xfs_agino_t		*agino,
2340	struct xfs_imap		*imap,
2341	struct xfs_dinode	**dipp,
2342	struct xfs_buf		**bpp,
2343	struct xfs_perag	*pag)
2344{
2345	struct xfs_mount	*mp = tp->t_mountp;
2346	xfs_agino_t		next_agino;
2347	int			error;
2348
2349	ASSERT(head_agino != target_agino);
2350	*bpp = NULL;
2351
2352	/* See if our backref cache can find it faster. */
2353	*agino = xfs_iunlink_lookup_backref(pag, target_agino);
2354	if (*agino != NULLAGINO) {
2355		error = xfs_iunlink_map_ino(tp, agno, *agino, imap, dipp, bpp);
2356		if (error)
2357			return error;
2358
2359		if (be32_to_cpu((*dipp)->di_next_unlinked) == target_agino)
2360			return 0;
2361
2362		/*
2363		 * If we get here the cache contents were corrupt, so drop the
2364		 * buffer and fall back to walking the bucket list.
2365		 */
2366		xfs_trans_brelse(tp, *bpp);
2367		*bpp = NULL;
2368		WARN_ON_ONCE(1);
2369	}
2370
2371	trace_xfs_iunlink_map_prev_fallback(mp, agno);
2372
2373	/* Otherwise, walk the entire bucket until we find it. */
2374	next_agino = head_agino;
2375	while (next_agino != target_agino) {
2376		xfs_agino_t	unlinked_agino;
2377
2378		if (*bpp)
2379			xfs_trans_brelse(tp, *bpp);
2380
2381		*agino = next_agino;
2382		error = xfs_iunlink_map_ino(tp, agno, next_agino, imap, dipp,
2383				bpp);
2384		if (error)
2385			return error;
2386
2387		unlinked_agino = be32_to_cpu((*dipp)->di_next_unlinked);
 
 
2388		/*
2389		 * Make sure this pointer is valid and isn't an obvious
2390		 * infinite loop.
2391		 */
2392		if (!xfs_verify_agino(mp, agno, unlinked_agino) ||
2393		    next_agino == unlinked_agino) {
2394			XFS_CORRUPTION_ERROR(__func__,
2395					XFS_ERRLEVEL_LOW, mp,
2396					*dipp, sizeof(**dipp));
2397			error = -EFSCORRUPTED;
2398			return error;
2399		}
2400		next_agino = unlinked_agino;
2401	}
2402
2403	return 0;
2404}
2405
2406/*
2407 * Pull the on-disk inode from the AGI unlinked list.
2408 */
2409STATIC int
2410xfs_iunlink_remove(
2411	struct xfs_trans	*tp,
2412	struct xfs_inode	*ip)
2413{
2414	struct xfs_mount	*mp = tp->t_mountp;
2415	struct xfs_agi		*agi;
2416	struct xfs_buf		*agibp;
2417	struct xfs_buf		*last_ibp;
2418	struct xfs_dinode	*last_dip = NULL;
2419	struct xfs_perag	*pag = NULL;
2420	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2421	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2422	xfs_agino_t		next_agino;
2423	xfs_agino_t		head_agino;
2424	short			bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2425	int			error;
2426
2427	trace_xfs_iunlink_remove(ip);
2428
2429	/* Get the agi buffer first.  It ensures lock ordering on the list. */
2430	error = xfs_read_agi(mp, tp, agno, &agibp);
2431	if (error)
2432		return error;
2433	agi = XFS_BUF_TO_AGI(agibp);
2434
2435	/*
2436	 * Get the index into the agi hash table for the list this inode will
2437	 * go on.  Make sure the head pointer isn't garbage.
2438	 */
2439	head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2440	if (!xfs_verify_agino(mp, agno, head_agino)) {
2441		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
2442				agi, sizeof(*agi));
2443		return -EFSCORRUPTED;
2444	}
2445
2446	/*
2447	 * Set our inode's next_unlinked pointer to NULL and then return
2448	 * the old pointer value so that we can update whatever was previous
2449	 * to us in the list to point to whatever was next in the list.
2450	 */
2451	error = xfs_iunlink_update_inode(tp, ip, agno, NULLAGINO, &next_agino);
2452	if (error)
2453		return error;
2454
2455	/*
2456	 * If there was a backref pointing from the next inode back to this
2457	 * one, remove it because we've removed this inode from the list.
2458	 *
2459	 * Later, if this inode was in the middle of the list we'll update
2460	 * this inode's backref to point from the next inode.
2461	 */
2462	if (next_agino != NULLAGINO) {
2463		pag = xfs_perag_get(mp, agno);
2464		error = xfs_iunlink_change_backref(pag, next_agino,
2465				NULLAGINO);
2466		if (error)
2467			goto out;
2468	}
2469
2470	if (head_agino == agino) {
2471		/* Point the head of the list to the next unlinked inode. */
2472		error = xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index,
2473				next_agino);
2474		if (error)
2475			goto out;
2476	} else {
2477		struct xfs_imap	imap;
2478		xfs_agino_t	prev_agino;
2479
2480		if (!pag)
2481			pag = xfs_perag_get(mp, agno);
2482
2483		/* We need to search the list for the inode being freed. */
2484		error = xfs_iunlink_map_prev(tp, agno, head_agino, agino,
2485				&prev_agino, &imap, &last_dip, &last_ibp,
2486				pag);
2487		if (error)
2488			goto out;
2489
2490		/* Point the previous inode on the list to the next inode. */
2491		xfs_iunlink_update_dinode(tp, agno, prev_agino, last_ibp,
2492				last_dip, &imap, next_agino);
2493
2494		/*
2495		 * Now we deal with the backref for this inode.  If this inode
2496		 * pointed at a real inode, change the backref that pointed to
2497		 * us to point to our old next.  If this inode was the end of
2498		 * the list, delete the backref that pointed to us.  Note that
2499		 * change_backref takes care of deleting the backref if
2500		 * next_agino is NULLAGINO.
2501		 */
2502		error = xfs_iunlink_change_backref(pag, agino, next_agino);
2503		if (error)
2504			goto out;
 
 
 
 
2505	}
2506
2507out:
2508	if (pag)
2509		xfs_perag_put(pag);
2510	return error;
2511}
2512
2513/*
2514 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2515 * inodes that are in memory - they all must be marked stale and attached to
2516 * the cluster buffer.
2517 */
2518STATIC int
2519xfs_ifree_cluster(
2520	xfs_inode_t		*free_ip,
2521	xfs_trans_t		*tp,
2522	struct xfs_icluster	*xic)
2523{
2524	xfs_mount_t		*mp = free_ip->i_mount;
 
2525	int			nbufs;
 
2526	int			i, j;
2527	int			ioffset;
2528	xfs_daddr_t		blkno;
2529	xfs_buf_t		*bp;
2530	xfs_inode_t		*ip;
2531	xfs_inode_log_item_t	*iip;
2532	struct xfs_log_item	*lip;
2533	struct xfs_perag	*pag;
2534	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
2535	xfs_ino_t		inum;
2536
2537	inum = xic->first_ino;
2538	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2539	nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
2540
2541	for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
2542		/*
2543		 * The allocation bitmap tells us which inodes of the chunk were
2544		 * physically allocated. Skip the cluster if an inode falls into
2545		 * a sparse region.
2546		 */
2547		ioffset = inum - xic->first_ino;
2548		if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2549			ASSERT(ioffset % igeo->inodes_per_cluster == 0);
2550			continue;
2551		}
2552
 
2553		blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2554					 XFS_INO_TO_AGBNO(mp, inum));
2555
2556		/*
2557		 * We obtain and lock the backing buffer first in the process
2558		 * here, as we have to ensure that any dirty inode that we
2559		 * can't get the flush lock on is attached to the buffer.
2560		 * If we scan the in-memory inodes first, then buffer IO can
2561		 * complete before we get a lock on it, and hence we may fail
2562		 * to mark all the active inodes on the buffer stale.
2563		 */
2564		bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2565					mp->m_bsize * igeo->blocks_per_cluster,
2566					XBF_UNMAPPED);
2567
2568		if (!bp)
2569			return -ENOMEM;
2570
2571		/*
2572		 * This buffer may not have been correctly initialised as we
2573		 * didn't read it from disk. That's not important because we are
2574		 * only using to mark the buffer as stale in the log, and to
2575		 * attach stale cached inodes on it. That means it will never be
2576		 * dispatched for IO. If it is, we want to know about it, and we
2577		 * want it to fail. We can acheive this by adding a write
2578		 * verifier to the buffer.
2579		 */
2580		bp->b_ops = &xfs_inode_buf_ops;
2581
2582		/*
2583		 * Walk the inodes already attached to the buffer and mark them
2584		 * stale. These will all have the flush locks held, so an
2585		 * in-memory inode walk can't lock them. By marking them all
2586		 * stale first, we will not attempt to lock them in the loop
2587		 * below as the XFS_ISTALE flag will be set.
2588		 */
2589		list_for_each_entry(lip, &bp->b_li_list, li_bio_list) {
 
2590			if (lip->li_type == XFS_LI_INODE) {
2591				iip = (xfs_inode_log_item_t *)lip;
2592				ASSERT(iip->ili_logged == 1);
2593				lip->li_cb = xfs_istale_done;
2594				xfs_trans_ail_copy_lsn(mp->m_ail,
2595							&iip->ili_flush_lsn,
2596							&iip->ili_item.li_lsn);
2597				xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2598			}
 
2599		}
2600
2601
2602		/*
2603		 * For each inode in memory attempt to add it to the inode
2604		 * buffer and set it up for being staled on buffer IO
2605		 * completion.  This is safe as we've locked out tail pushing
2606		 * and flushing by locking the buffer.
2607		 *
2608		 * We have already marked every inode that was part of a
2609		 * transaction stale above, which means there is no point in
2610		 * even trying to lock them.
2611		 */
2612		for (i = 0; i < igeo->inodes_per_cluster; i++) {
2613retry:
2614			rcu_read_lock();
2615			ip = radix_tree_lookup(&pag->pag_ici_root,
2616					XFS_INO_TO_AGINO(mp, (inum + i)));
2617
2618			/* Inode not in memory, nothing to do */
2619			if (!ip) {
2620				rcu_read_unlock();
2621				continue;
2622			}
2623
2624			/*
2625			 * because this is an RCU protected lookup, we could
2626			 * find a recently freed or even reallocated inode
2627			 * during the lookup. We need to check under the
2628			 * i_flags_lock for a valid inode here. Skip it if it
2629			 * is not valid, the wrong inode or stale.
2630			 */
2631			spin_lock(&ip->i_flags_lock);
2632			if (ip->i_ino != inum + i ||
2633			    __xfs_iflags_test(ip, XFS_ISTALE)) {
2634				spin_unlock(&ip->i_flags_lock);
2635				rcu_read_unlock();
2636				continue;
2637			}
2638			spin_unlock(&ip->i_flags_lock);
2639
2640			/*
2641			 * Don't try to lock/unlock the current inode, but we
2642			 * _cannot_ skip the other inodes that we did not find
2643			 * in the list attached to the buffer and are not
2644			 * already marked stale. If we can't lock it, back off
2645			 * and retry.
2646			 */
2647			if (ip != free_ip) {
2648				if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2649					rcu_read_unlock();
2650					delay(1);
2651					goto retry;
2652				}
2653
2654				/*
2655				 * Check the inode number again in case we're
2656				 * racing with freeing in xfs_reclaim_inode().
2657				 * See the comments in that function for more
2658				 * information as to why the initial check is
2659				 * not sufficient.
2660				 */
2661				if (ip->i_ino != inum + i) {
2662					xfs_iunlock(ip, XFS_ILOCK_EXCL);
2663					rcu_read_unlock();
2664					continue;
2665				}
2666			}
2667			rcu_read_unlock();
2668
2669			xfs_iflock(ip);
2670			xfs_iflags_set(ip, XFS_ISTALE);
2671
2672			/*
2673			 * we don't need to attach clean inodes or those only
2674			 * with unlogged changes (which we throw away, anyway).
2675			 */
2676			iip = ip->i_itemp;
2677			if (!iip || xfs_inode_clean(ip)) {
2678				ASSERT(ip != free_ip);
2679				xfs_ifunlock(ip);
2680				xfs_iunlock(ip, XFS_ILOCK_EXCL);
2681				continue;
2682			}
2683
2684			iip->ili_last_fields = iip->ili_fields;
2685			iip->ili_fields = 0;
2686			iip->ili_fsync_fields = 0;
2687			iip->ili_logged = 1;
2688			xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2689						&iip->ili_item.li_lsn);
2690
2691			xfs_buf_attach_iodone(bp, xfs_istale_done,
2692						  &iip->ili_item);
2693
2694			if (ip != free_ip)
2695				xfs_iunlock(ip, XFS_ILOCK_EXCL);
2696		}
2697
2698		xfs_trans_stale_inode_buf(tp, bp);
2699		xfs_trans_binval(tp, bp);
2700	}
2701
2702	xfs_perag_put(pag);
2703	return 0;
2704}
2705
2706/*
2707 * Free any local-format buffers sitting around before we reset to
2708 * extents format.
2709 */
2710static inline void
2711xfs_ifree_local_data(
2712	struct xfs_inode	*ip,
2713	int			whichfork)
2714{
2715	struct xfs_ifork	*ifp;
2716
2717	if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
2718		return;
2719
2720	ifp = XFS_IFORK_PTR(ip, whichfork);
2721	xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
2722}
2723
2724/*
2725 * This is called to return an inode to the inode free list.
2726 * The inode should already be truncated to 0 length and have
2727 * no pages associated with it.  This routine also assumes that
2728 * the inode is already a part of the transaction.
2729 *
2730 * The on-disk copy of the inode will have been added to the list
2731 * of unlinked inodes in the AGI. We need to remove the inode from
2732 * that list atomically with respect to freeing it here.
2733 */
2734int
2735xfs_ifree(
2736	struct xfs_trans	*tp,
2737	struct xfs_inode	*ip)
 
2738{
2739	int			error;
2740	struct xfs_icluster	xic = { 0 };
 
 
 
2741
2742	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2743	ASSERT(VFS_I(ip)->i_nlink == 0);
2744	ASSERT(ip->i_d.di_nextents == 0);
2745	ASSERT(ip->i_d.di_anextents == 0);
2746	ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2747	ASSERT(ip->i_d.di_nblocks == 0);
2748
2749	/*
2750	 * Pull the on-disk inode from the AGI unlinked list.
2751	 */
2752	error = xfs_iunlink_remove(tp, ip);
2753	if (error)
2754		return error;
 
2755
2756	error = xfs_difree(tp, ip->i_ino, &xic);
2757	if (error)
2758		return error;
2759
2760	xfs_ifree_local_data(ip, XFS_DATA_FORK);
2761	xfs_ifree_local_data(ip, XFS_ATTR_FORK);
2762
2763	VFS_I(ip)->i_mode = 0;		/* mark incore inode as free */
2764	ip->i_d.di_flags = 0;
2765	ip->i_d.di_flags2 = 0;
2766	ip->i_d.di_dmevmask = 0;
2767	ip->i_d.di_forkoff = 0;		/* mark the attr fork not in use */
2768	ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2769	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2770
2771	/* Don't attempt to replay owner changes for a deleted inode */
2772	ip->i_itemp->ili_fields &= ~(XFS_ILOG_AOWNER|XFS_ILOG_DOWNER);
2773
2774	/*
2775	 * Bump the generation count so no one will be confused
2776	 * by reincarnations of this inode.
2777	 */
2778	VFS_I(ip)->i_generation++;
 
2779	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2780
2781	if (xic.deleted)
2782		error = xfs_ifree_cluster(ip, tp, &xic);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2783
2784	return error;
2785}
2786
2787/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2788 * This is called to unpin an inode.  The caller must have the inode locked
2789 * in at least shared mode so that the buffer cannot be subsequently pinned
2790 * once someone is waiting for it to be unpinned.
2791 */
2792static void
2793xfs_iunpin(
2794	struct xfs_inode	*ip)
2795{
2796	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2797
2798	trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2799
2800	/* Give the log a push to start the unpinning I/O */
2801	xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0, NULL);
2802
2803}
2804
2805static void
2806__xfs_iunpin_wait(
2807	struct xfs_inode	*ip)
2808{
2809	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2810	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2811
2812	xfs_iunpin(ip);
2813
2814	do {
2815		prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2816		if (xfs_ipincount(ip))
2817			io_schedule();
2818	} while (xfs_ipincount(ip));
2819	finish_wait(wq, &wait.wq_entry);
2820}
2821
2822void
2823xfs_iunpin_wait(
2824	struct xfs_inode	*ip)
2825{
2826	if (xfs_ipincount(ip))
2827		__xfs_iunpin_wait(ip);
2828}
2829
2830/*
2831 * Removing an inode from the namespace involves removing the directory entry
2832 * and dropping the link count on the inode. Removing the directory entry can
2833 * result in locking an AGF (directory blocks were freed) and removing a link
2834 * count can result in placing the inode on an unlinked list which results in
2835 * locking an AGI.
2836 *
2837 * The big problem here is that we have an ordering constraint on AGF and AGI
2838 * locking - inode allocation locks the AGI, then can allocate a new extent for
2839 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2840 * removes the inode from the unlinked list, requiring that we lock the AGI
2841 * first, and then freeing the inode can result in an inode chunk being freed
2842 * and hence freeing disk space requiring that we lock an AGF.
2843 *
2844 * Hence the ordering that is imposed by other parts of the code is AGI before
2845 * AGF. This means we cannot remove the directory entry before we drop the inode
2846 * reference count and put it on the unlinked list as this results in a lock
2847 * order of AGF then AGI, and this can deadlock against inode allocation and
2848 * freeing. Therefore we must drop the link counts before we remove the
2849 * directory entry.
2850 *
2851 * This is still safe from a transactional point of view - it is not until we
2852 * get to xfs_defer_finish() that we have the possibility of multiple
2853 * transactions in this operation. Hence as long as we remove the directory
2854 * entry and drop the link count in the first transaction of the remove
2855 * operation, there are no transactional constraints on the ordering here.
2856 */
2857int
2858xfs_remove(
2859	xfs_inode_t             *dp,
2860	struct xfs_name		*name,
2861	xfs_inode_t		*ip)
2862{
2863	xfs_mount_t		*mp = dp->i_mount;
2864	xfs_trans_t             *tp = NULL;
2865	int			is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2866	int                     error = 0;
2867	uint			resblks;
2868
2869	trace_xfs_remove(dp, name);
2870
2871	if (XFS_FORCED_SHUTDOWN(mp))
2872		return -EIO;
2873
2874	error = xfs_qm_dqattach(dp);
2875	if (error)
2876		goto std_return;
2877
2878	error = xfs_qm_dqattach(ip);
2879	if (error)
2880		goto std_return;
2881
2882	/*
2883	 * We try to get the real space reservation first,
2884	 * allowing for directory btree deletion(s) implying
2885	 * possible bmap insert(s).  If we can't get the space
2886	 * reservation then we use 0 instead, and avoid the bmap
2887	 * btree insert(s) in the directory code by, if the bmap
2888	 * insert tries to happen, instead trimming the LAST
2889	 * block from the directory.
2890	 */
2891	resblks = XFS_REMOVE_SPACE_RES(mp);
2892	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2893	if (error == -ENOSPC) {
2894		resblks = 0;
2895		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2896				&tp);
2897	}
2898	if (error) {
2899		ASSERT(error != -ENOSPC);
2900		goto std_return;
2901	}
2902
2903	xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
2904
2905	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2906	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 
2907
2908	/*
2909	 * If we're removing a directory perform some additional validation.
2910	 */
2911	if (is_dir) {
2912		ASSERT(VFS_I(ip)->i_nlink >= 2);
2913		if (VFS_I(ip)->i_nlink != 2) {
2914			error = -ENOTEMPTY;
2915			goto out_trans_cancel;
2916		}
2917		if (!xfs_dir_isempty(ip)) {
2918			error = -ENOTEMPTY;
2919			goto out_trans_cancel;
 
 
 
 
 
 
 
2920		}
2921
2922		/* Drop the link from ip's "..".  */
2923		error = xfs_droplink(tp, dp);
2924		if (error)
2925			goto out_trans_cancel;
2926
2927		/* Drop the "." link from ip to self.  */
2928		error = xfs_droplink(tp, ip);
2929		if (error)
2930			goto out_trans_cancel;
2931	} else {
2932		/*
2933		 * When removing a non-directory we need to log the parent
2934		 * inode here.  For a directory this is done implicitly
2935		 * by the xfs_droplink call for the ".." entry.
2936		 */
2937		xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2938	}
2939	xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2940
2941	/* Drop the link from dp to ip. */
2942	error = xfs_droplink(tp, ip);
2943	if (error)
2944		goto out_trans_cancel;
2945
2946	error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
2947	if (error) {
2948		ASSERT(error != -ENOENT);
2949		goto out_trans_cancel;
2950	}
 
 
2951
2952	/*
2953	 * If this is a synchronous mount, make sure that the
2954	 * remove transaction goes to disk before returning to
2955	 * the user.
2956	 */
2957	if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2958		xfs_trans_set_sync(tp);
2959
2960	error = xfs_trans_commit(tp);
2961	if (error)
2962		goto std_return;
2963
2964	if (is_dir && xfs_inode_is_filestream(ip))
2965		xfs_filestream_deassociate(ip);
2966
2967	return 0;
2968
2969 out_trans_cancel:
2970	xfs_trans_cancel(tp);
2971 std_return:
2972	return error;
2973}
2974
2975/*
2976 * Enter all inodes for a rename transaction into a sorted array.
 
 
 
 
 
 
 
2977 */
2978#define __XFS_SORT_INODES	5
2979STATIC void
2980xfs_sort_for_rename(
2981	struct xfs_inode	*dp1,	/* in: old (source) directory inode */
2982	struct xfs_inode	*dp2,	/* in: new (target) directory inode */
2983	struct xfs_inode	*ip1,	/* in: inode of old entry */
2984	struct xfs_inode	*ip2,	/* in: inode of new entry */
2985	struct xfs_inode	*wip,	/* in: whiteout inode */
2986	struct xfs_inode	**i_tab,/* out: sorted array of inodes */
2987	int			*num_inodes)  /* in/out: inodes in array */
2988{
2989	int			i, j;
2990
2991	ASSERT(*num_inodes == __XFS_SORT_INODES);
2992	memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
 
 
 
 
 
 
 
 
2993
 
 
 
2994	/*
2995	 * i_tab contains a list of pointers to inodes.  We initialize
2996	 * the table here & we'll sort it.  We will then use it to
2997	 * order the acquisition of the inode locks.
2998	 *
2999	 * Note that the table may contain duplicates.  e.g., dp1 == dp2.
3000	 */
3001	i = 0;
3002	i_tab[i++] = dp1;
3003	i_tab[i++] = dp2;
3004	i_tab[i++] = ip1;
3005	if (ip2)
3006		i_tab[i++] = ip2;
3007	if (wip)
3008		i_tab[i++] = wip;
3009	*num_inodes = i;
3010
3011	/*
3012	 * Sort the elements via bubble sort.  (Remember, there are at
3013	 * most 5 elements to sort, so this is adequate.)
3014	 */
3015	for (i = 0; i < *num_inodes; i++) {
3016		for (j = 1; j < *num_inodes; j++) {
3017			if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
3018				struct xfs_inode *temp = i_tab[j];
3019				i_tab[j] = i_tab[j-1];
3020				i_tab[j-1] = temp;
3021			}
3022		}
3023	}
3024}
3025
3026static int
3027xfs_finish_rename(
3028	struct xfs_trans	*tp)
3029{
3030	/*
3031	 * If this is a synchronous mount, make sure that the rename transaction
3032	 * goes to disk before returning to the user.
3033	 */
3034	if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
3035		xfs_trans_set_sync(tp);
3036
3037	return xfs_trans_commit(tp);
3038}
3039
3040/*
3041 * xfs_cross_rename()
3042 *
3043 * responsible for handling RENAME_EXCHANGE flag in renameat2() sytemcall
3044 */
3045STATIC int
3046xfs_cross_rename(
3047	struct xfs_trans	*tp,
3048	struct xfs_inode	*dp1,
3049	struct xfs_name		*name1,
3050	struct xfs_inode	*ip1,
3051	struct xfs_inode	*dp2,
3052	struct xfs_name		*name2,
3053	struct xfs_inode	*ip2,
3054	int			spaceres)
3055{
3056	int		error = 0;
3057	int		ip1_flags = 0;
3058	int		ip2_flags = 0;
3059	int		dp2_flags = 0;
3060
3061	/* Swap inode number for dirent in first parent */
3062	error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
3063	if (error)
3064		goto out_trans_abort;
3065
3066	/* Swap inode number for dirent in second parent */
3067	error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
3068	if (error)
3069		goto out_trans_abort;
3070
3071	/*
3072	 * If we're renaming one or more directories across different parents,
3073	 * update the respective ".." entries (and link counts) to match the new
3074	 * parents.
3075	 */
3076	if (dp1 != dp2) {
3077		dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
3078
3079		if (S_ISDIR(VFS_I(ip2)->i_mode)) {
3080			error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
3081						dp1->i_ino, spaceres);
3082			if (error)
3083				goto out_trans_abort;
3084
3085			/* transfer ip2 ".." reference to dp1 */
3086			if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
3087				error = xfs_droplink(tp, dp2);
3088				if (error)
3089					goto out_trans_abort;
3090				xfs_bumplink(tp, dp1);
3091			}
3092
3093			/*
3094			 * Although ip1 isn't changed here, userspace needs
3095			 * to be warned about the change, so that applications
3096			 * relying on it (like backup ones), will properly
3097			 * notify the change
3098			 */
3099			ip1_flags |= XFS_ICHGTIME_CHG;
3100			ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
3101		}
 
3102
3103		if (S_ISDIR(VFS_I(ip1)->i_mode)) {
3104			error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
3105						dp2->i_ino, spaceres);
3106			if (error)
3107				goto out_trans_abort;
3108
3109			/* transfer ip1 ".." reference to dp2 */
3110			if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
3111				error = xfs_droplink(tp, dp1);
3112				if (error)
3113					goto out_trans_abort;
3114				xfs_bumplink(tp, dp2);
3115			}
3116
3117			/*
3118			 * Although ip2 isn't changed here, userspace needs
3119			 * to be warned about the change, so that applications
3120			 * relying on it (like backup ones), will properly
3121			 * notify the change
3122			 */
3123			ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
3124			ip2_flags |= XFS_ICHGTIME_CHG;
3125		}
3126	}
3127
3128	if (ip1_flags) {
3129		xfs_trans_ichgtime(tp, ip1, ip1_flags);
3130		xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
3131	}
3132	if (ip2_flags) {
3133		xfs_trans_ichgtime(tp, ip2, ip2_flags);
3134		xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
3135	}
3136	if (dp2_flags) {
3137		xfs_trans_ichgtime(tp, dp2, dp2_flags);
3138		xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
3139	}
3140	xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3141	xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
3142	return xfs_finish_rename(tp);
3143
3144out_trans_abort:
3145	xfs_trans_cancel(tp);
3146	return error;
3147}
3148
3149/*
3150 * xfs_rename_alloc_whiteout()
3151 *
3152 * Return a referenced, unlinked, unlocked inode that that can be used as a
3153 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
3154 * crash between allocating the inode and linking it into the rename transaction
3155 * recovery will free the inode and we won't leak it.
3156 */
3157static int
3158xfs_rename_alloc_whiteout(
3159	struct xfs_inode	*dp,
3160	struct xfs_inode	**wip)
3161{
3162	struct xfs_inode	*tmpfile;
3163	int			error;
3164
3165	error = xfs_create_tmpfile(dp, S_IFCHR | WHITEOUT_MODE, &tmpfile);
3166	if (error)
3167		return error;
3168
3169	/*
3170	 * Prepare the tmpfile inode as if it were created through the VFS.
3171	 * Complete the inode setup and flag it as linkable.  nlink is already
3172	 * zero, so we can skip the drop_nlink.
3173	 */
3174	xfs_setup_iops(tmpfile);
3175	xfs_finish_inode_setup(tmpfile);
3176	VFS_I(tmpfile)->i_state |= I_LINKABLE;
3177
3178	*wip = tmpfile;
3179	return 0;
3180}
3181
3182/*
3183 * xfs_rename
3184 */
3185int
3186xfs_rename(
3187	struct xfs_inode	*src_dp,
3188	struct xfs_name		*src_name,
3189	struct xfs_inode	*src_ip,
3190	struct xfs_inode	*target_dp,
3191	struct xfs_name		*target_name,
3192	struct xfs_inode	*target_ip,
3193	unsigned int		flags)
3194{
3195	struct xfs_mount	*mp = src_dp->i_mount;
3196	struct xfs_trans	*tp;
3197	struct xfs_inode	*wip = NULL;		/* whiteout inode */
3198	struct xfs_inode	*inodes[__XFS_SORT_INODES];
3199	int			num_inodes = __XFS_SORT_INODES;
3200	bool			new_parent = (src_dp != target_dp);
3201	bool			src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
3202	int			spaceres;
3203	int			error;
3204
3205	trace_xfs_rename(src_dp, target_dp, src_name, target_name);
3206
3207	if ((flags & RENAME_EXCHANGE) && !target_ip)
3208		return -EINVAL;
3209
3210	/*
3211	 * If we are doing a whiteout operation, allocate the whiteout inode
3212	 * we will be placing at the target and ensure the type is set
3213	 * appropriately.
3214	 */
3215	if (flags & RENAME_WHITEOUT) {
3216		ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
3217		error = xfs_rename_alloc_whiteout(target_dp, &wip);
3218		if (error)
3219			return error;
3220
3221		/* setup target dirent info as whiteout */
3222		src_name->type = XFS_DIR3_FT_CHRDEV;
3223	}
3224
3225	xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
3226				inodes, &num_inodes);
3227
3228	spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
3229	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
3230	if (error == -ENOSPC) {
3231		spaceres = 0;
3232		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
3233				&tp);
3234	}
3235	if (error)
3236		goto out_release_wip;
3237
3238	/*
3239	 * Attach the dquots to the inodes
3240	 */
3241	error = xfs_qm_vop_rename_dqattach(inodes);
3242	if (error)
3243		goto out_trans_cancel;
3244
3245	/*
3246	 * Lock all the participating inodes. Depending upon whether
3247	 * the target_name exists in the target directory, and
3248	 * whether the target directory is the same as the source
3249	 * directory, we can lock from 2 to 4 inodes.
3250	 */
3251	xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
3252
3253	/*
3254	 * Join all the inodes to the transaction. From this point on,
3255	 * we can rely on either trans_commit or trans_cancel to unlock
3256	 * them.
3257	 */
3258	xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
3259	if (new_parent)
3260		xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
3261	xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
3262	if (target_ip)
3263		xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
3264	if (wip)
3265		xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
3266
3267	/*
3268	 * If we are using project inheritance, we only allow renames
3269	 * into our tree when the project IDs are the same; else the
3270	 * tree quota mechanism would be circumvented.
3271	 */
3272	if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
3273		     (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
3274		error = -EXDEV;
3275		goto out_trans_cancel;
3276	}
3277
3278	/* RENAME_EXCHANGE is unique from here on. */
3279	if (flags & RENAME_EXCHANGE)
3280		return xfs_cross_rename(tp, src_dp, src_name, src_ip,
3281					target_dp, target_name, target_ip,
3282					spaceres);
3283
3284	/*
3285	 * Check for expected errors before we dirty the transaction
3286	 * so we can return an error without a transaction abort.
3287	 */
3288	if (target_ip == NULL) {
3289		/*
3290		 * If there's no space reservation, check the entry will
3291		 * fit before actually inserting it.
3292		 */
3293		if (!spaceres) {
3294			error = xfs_dir_canenter(tp, target_dp, target_name);
3295			if (error)
3296				goto out_trans_cancel;
3297		}
3298	} else {
3299		/*
3300		 * If target exists and it's a directory, check that whether
3301		 * it can be destroyed.
3302		 */
3303		if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
3304		    (!xfs_dir_isempty(target_ip) ||
3305		     (VFS_I(target_ip)->i_nlink > 2))) {
3306			error = -EEXIST;
3307			goto out_trans_cancel;
3308		}
3309	}
3310
3311	/*
3312	 * Directory entry creation below may acquire the AGF. Remove
3313	 * the whiteout from the unlinked list first to preserve correct
3314	 * AGI/AGF locking order. This dirties the transaction so failures
3315	 * after this point will abort and log recovery will clean up the
3316	 * mess.
3317	 *
3318	 * For whiteouts, we need to bump the link count on the whiteout
3319	 * inode. After this point, we have a real link, clear the tmpfile
3320	 * state flag from the inode so it doesn't accidentally get misused
3321	 * in future.
3322	 */
3323	if (wip) {
3324		ASSERT(VFS_I(wip)->i_nlink == 0);
3325		error = xfs_iunlink_remove(tp, wip);
3326		if (error)
3327			goto out_trans_cancel;
3328
3329		xfs_bumplink(tp, wip);
3330		xfs_trans_log_inode(tp, wip, XFS_ILOG_CORE);
3331		VFS_I(wip)->i_state &= ~I_LINKABLE;
3332	}
3333
3334	/*
3335	 * Set up the target.
3336	 */
3337	if (target_ip == NULL) {
3338		/*
3339		 * If target does not exist and the rename crosses
3340		 * directories, adjust the target directory link count
3341		 * to account for the ".." reference from the new entry.
3342		 */
3343		error = xfs_dir_createname(tp, target_dp, target_name,
3344					   src_ip->i_ino, spaceres);
3345		if (error)
3346			goto out_trans_cancel;
3347
3348		xfs_trans_ichgtime(tp, target_dp,
3349					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3350
3351		if (new_parent && src_is_directory) {
3352			xfs_bumplink(tp, target_dp);
 
 
3353		}
3354	} else { /* target_ip != NULL */
3355		/*
3356		 * Link the source inode under the target name.
3357		 * If the source inode is a directory and we are moving
3358		 * it across directories, its ".." entry will be
3359		 * inconsistent until we replace that down below.
3360		 *
3361		 * In case there is already an entry with the same
3362		 * name at the destination directory, remove it first.
3363		 */
3364		error = xfs_dir_replace(tp, target_dp, target_name,
3365					src_ip->i_ino, spaceres);
3366		if (error)
3367			goto out_trans_cancel;
3368
3369		xfs_trans_ichgtime(tp, target_dp,
3370					XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3371
3372		/*
3373		 * Decrement the link count on the target since the target
3374		 * dir no longer points to it.
3375		 */
3376		error = xfs_droplink(tp, target_ip);
3377		if (error)
3378			goto out_trans_cancel;
3379
3380		if (src_is_directory) {
3381			/*
3382			 * Drop the link from the old "." entry.
3383			 */
3384			error = xfs_droplink(tp, target_ip);
3385			if (error)
3386				goto out_trans_cancel;
3387		}
3388	} /* target_ip != NULL */
3389
3390	/*
3391	 * Remove the source.
3392	 */
3393	if (new_parent && src_is_directory) {
3394		/*
3395		 * Rewrite the ".." entry to point to the new
3396		 * directory.
3397		 */
3398		error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3399					target_dp->i_ino, spaceres);
3400		ASSERT(error != -EEXIST);
3401		if (error)
3402			goto out_trans_cancel;
3403	}
3404
3405	/*
3406	 * We always want to hit the ctime on the source inode.
3407	 *
3408	 * This isn't strictly required by the standards since the source
3409	 * inode isn't really being changed, but old unix file systems did
3410	 * it and some incremental backup programs won't work without it.
3411	 */
3412	xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3413	xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3414
3415	/*
3416	 * Adjust the link count on src_dp.  This is necessary when
3417	 * renaming a directory, either within one parent when
3418	 * the target existed, or across two parent directories.
3419	 */
3420	if (src_is_directory && (new_parent || target_ip != NULL)) {
3421
3422		/*
3423		 * Decrement link count on src_directory since the
3424		 * entry that's moved no longer points to it.
3425		 */
3426		error = xfs_droplink(tp, src_dp);
3427		if (error)
3428			goto out_trans_cancel;
3429	}
3430
3431	/*
3432	 * For whiteouts, we only need to update the source dirent with the
3433	 * inode number of the whiteout inode rather than removing it
3434	 * altogether.
3435	 */
3436	if (wip) {
3437		error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3438					spaceres);
3439	} else
3440		error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3441					   spaceres);
3442	if (error)
3443		goto out_trans_cancel;
3444
3445	xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3446	xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3447	if (new_parent)
3448		xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3449
3450	error = xfs_finish_rename(tp);
3451	if (wip)
3452		xfs_irele(wip);
3453	return error;
3454
3455out_trans_cancel:
3456	xfs_trans_cancel(tp);
3457out_release_wip:
3458	if (wip)
3459		xfs_irele(wip);
3460	return error;
3461}
3462
3463STATIC int
3464xfs_iflush_cluster(
3465	struct xfs_inode	*ip,
3466	struct xfs_buf		*bp)
3467{
3468	struct xfs_mount	*mp = ip->i_mount;
3469	struct xfs_perag	*pag;
3470	unsigned long		first_index, mask;
3471	int			cilist_size;
3472	struct xfs_inode	**cilist;
3473	struct xfs_inode	*cip;
3474	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
3475	int			nr_found;
3476	int			clcount = 0;
 
3477	int			i;
3478
3479	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
3480
3481	cilist_size = igeo->inodes_per_cluster * sizeof(struct xfs_inode *);
3482	cilist = kmem_alloc(cilist_size, KM_MAYFAIL|KM_NOFS);
3483	if (!cilist)
 
3484		goto out_put;
3485
3486	mask = ~(igeo->inodes_per_cluster - 1);
3487	first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
3488	rcu_read_lock();
3489	/* really need a gang lookup range call here */
3490	nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)cilist,
3491					first_index, igeo->inodes_per_cluster);
3492	if (nr_found == 0)
3493		goto out_free;
3494
3495	for (i = 0; i < nr_found; i++) {
3496		cip = cilist[i];
3497		if (cip == ip)
3498			continue;
3499
3500		/*
3501		 * because this is an RCU protected lookup, we could find a
3502		 * recently freed or even reallocated inode during the lookup.
3503		 * We need to check under the i_flags_lock for a valid inode
3504		 * here. Skip it if it is not valid or the wrong inode.
3505		 */
3506		spin_lock(&cip->i_flags_lock);
3507		if (!cip->i_ino ||
3508		    __xfs_iflags_test(cip, XFS_ISTALE)) {
3509			spin_unlock(&cip->i_flags_lock);
3510			continue;
3511		}
3512
3513		/*
3514		 * Once we fall off the end of the cluster, no point checking
3515		 * any more inodes in the list because they will also all be
3516		 * outside the cluster.
3517		 */
3518		if ((XFS_INO_TO_AGINO(mp, cip->i_ino) & mask) != first_index) {
3519			spin_unlock(&cip->i_flags_lock);
3520			break;
3521		}
3522		spin_unlock(&cip->i_flags_lock);
3523
3524		/*
3525		 * Do an un-protected check to see if the inode is dirty and
3526		 * is a candidate for flushing.  These checks will be repeated
3527		 * later after the appropriate locks are acquired.
3528		 */
3529		if (xfs_inode_clean(cip) && xfs_ipincount(cip) == 0)
3530			continue;
3531
3532		/*
3533		 * Try to get locks.  If any are unavailable or it is pinned,
3534		 * then this inode cannot be flushed and is skipped.
3535		 */
3536
3537		if (!xfs_ilock_nowait(cip, XFS_ILOCK_SHARED))
3538			continue;
3539		if (!xfs_iflock_nowait(cip)) {
3540			xfs_iunlock(cip, XFS_ILOCK_SHARED);
3541			continue;
3542		}
3543		if (xfs_ipincount(cip)) {
3544			xfs_ifunlock(cip);
3545			xfs_iunlock(cip, XFS_ILOCK_SHARED);
3546			continue;
3547		}
3548
3549
3550		/*
3551		 * Check the inode number again, just to be certain we are not
3552		 * racing with freeing in xfs_reclaim_inode(). See the comments
3553		 * in that function for more information as to why the initial
3554		 * check is not sufficient.
3555		 */
3556		if (!cip->i_ino) {
3557			xfs_ifunlock(cip);
3558			xfs_iunlock(cip, XFS_ILOCK_SHARED);
3559			continue;
3560		}
3561
3562		/*
3563		 * arriving here means that this inode can be flushed.  First
3564		 * re-check that it's dirty before flushing.
3565		 */
3566		if (!xfs_inode_clean(cip)) {
3567			int	error;
3568			error = xfs_iflush_int(cip, bp);
3569			if (error) {
3570				xfs_iunlock(cip, XFS_ILOCK_SHARED);
3571				goto cluster_corrupt_out;
3572			}
3573			clcount++;
3574		} else {
3575			xfs_ifunlock(cip);
3576		}
3577		xfs_iunlock(cip, XFS_ILOCK_SHARED);
3578	}
3579
3580	if (clcount) {
3581		XFS_STATS_INC(mp, xs_icluster_flushcnt);
3582		XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3583	}
3584
3585out_free:
3586	rcu_read_unlock();
3587	kmem_free(cilist);
3588out_put:
3589	xfs_perag_put(pag);
3590	return 0;
3591
3592
3593cluster_corrupt_out:
3594	/*
3595	 * Corruption detected in the clustering loop.  Invalidate the
3596	 * inode buffer and shut down the filesystem.
3597	 */
3598	rcu_read_unlock();
3599
3600	/*
3601	 * We'll always have an inode attached to the buffer for completion
3602	 * process by the time we are called from xfs_iflush(). Hence we have
3603	 * always need to do IO completion processing to abort the inodes
3604	 * attached to the buffer.  handle them just like the shutdown case in
3605	 * xfs_buf_submit().
3606	 */
3607	ASSERT(bp->b_iodone);
3608	bp->b_flags |= XBF_ASYNC;
3609	bp->b_flags &= ~XBF_DONE;
3610	xfs_buf_stale(bp);
3611	xfs_buf_ioerror(bp, -EIO);
3612	xfs_buf_ioend(bp);
3613
3614	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3615
3616	/* abort the corrupt inode, as it was not attached to the buffer */
3617	xfs_iflush_abort(cip, false);
3618	kmem_free(cilist);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3619	xfs_perag_put(pag);
3620	return -EFSCORRUPTED;
3621}
3622
3623/*
3624 * Flush dirty inode metadata into the backing buffer.
3625 *
3626 * The caller must have the inode lock and the inode flush lock held.  The
3627 * inode lock will still be held upon return to the caller, and the inode
3628 * flush lock will be released after the inode has reached the disk.
3629 *
3630 * The caller must write out the buffer returned in *bpp and release it.
3631 */
3632int
3633xfs_iflush(
3634	struct xfs_inode	*ip,
3635	struct xfs_buf		**bpp)
3636{
3637	struct xfs_mount	*mp = ip->i_mount;
3638	struct xfs_buf		*bp = NULL;
3639	struct xfs_dinode	*dip;
3640	int			error;
3641
3642	XFS_STATS_INC(mp, xs_iflush_count);
3643
3644	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3645	ASSERT(xfs_isiflocked(ip));
3646	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3647	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3648
3649	*bpp = NULL;
3650
3651	xfs_iunpin_wait(ip);
3652
3653	/*
3654	 * For stale inodes we cannot rely on the backing buffer remaining
3655	 * stale in cache for the remaining life of the stale inode and so
3656	 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3657	 * inodes below. We have to check this after ensuring the inode is
3658	 * unpinned so that it is safe to reclaim the stale inode after the
3659	 * flush call.
3660	 */
3661	if (xfs_iflags_test(ip, XFS_ISTALE)) {
3662		xfs_ifunlock(ip);
3663		return 0;
3664	}
3665
3666	/*
3667	 * This may have been unpinned because the filesystem is shutting
3668	 * down forcibly. If that's the case we must not write this inode
3669	 * to disk, because the log record didn't make it to disk.
3670	 *
3671	 * We also have to remove the log item from the AIL in this case,
3672	 * as we wait for an empty AIL as part of the unmount process.
3673	 */
3674	if (XFS_FORCED_SHUTDOWN(mp)) {
3675		error = -EIO;
3676		goto abort_out;
3677	}
3678
3679	/*
3680	 * Get the buffer containing the on-disk inode. We are doing a try-lock
3681	 * operation here, so we may get  an EAGAIN error. In that case, we
3682	 * simply want to return with the inode still dirty.
3683	 *
3684	 * If we get any other error, we effectively have a corruption situation
3685	 * and we cannot flush the inode, so we treat it the same as failing
3686	 * xfs_iflush_int().
3687	 */
3688	error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3689			       0);
3690	if (error == -EAGAIN) {
3691		xfs_ifunlock(ip);
3692		return error;
3693	}
3694	if (error)
3695		goto corrupt_out;
3696
3697	/*
3698	 * First flush out the inode that xfs_iflush was called with.
3699	 */
3700	error = xfs_iflush_int(ip, bp);
3701	if (error)
3702		goto corrupt_out;
3703
3704	/*
3705	 * If the buffer is pinned then push on the log now so we won't
3706	 * get stuck waiting in the write for too long.
3707	 */
3708	if (xfs_buf_ispinned(bp))
3709		xfs_log_force(mp, 0);
3710
3711	/*
3712	 * inode clustering: try to gather other inodes into this write
3713	 *
3714	 * Note: Any error during clustering will result in the filesystem
3715	 * being shut down and completion callbacks run on the cluster buffer.
3716	 * As we have already flushed and attached this inode to the buffer,
3717	 * it has already been aborted and released by xfs_iflush_cluster() and
3718	 * so we have no further error handling to do here.
3719	 */
3720	error = xfs_iflush_cluster(ip, bp);
3721	if (error)
3722		return error;
3723
3724	*bpp = bp;
3725	return 0;
3726
3727corrupt_out:
3728	if (bp)
3729		xfs_buf_relse(bp);
3730	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 
 
3731abort_out:
3732	/* abort the corrupt inode, as it was not attached to the buffer */
 
 
3733	xfs_iflush_abort(ip, false);
3734	return error;
3735}
3736
3737/*
3738 * If there are inline format data / attr forks attached to this inode,
3739 * make sure they're not corrupt.
3740 */
3741bool
3742xfs_inode_verify_forks(
3743	struct xfs_inode	*ip)
3744{
3745	struct xfs_ifork	*ifp;
3746	xfs_failaddr_t		fa;
3747
3748	fa = xfs_ifork_verify_data(ip, &xfs_default_ifork_ops);
3749	if (fa) {
3750		ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
3751		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "data fork",
3752				ifp->if_u1.if_data, ifp->if_bytes, fa);
3753		return false;
3754	}
3755
3756	fa = xfs_ifork_verify_attr(ip, &xfs_default_ifork_ops);
3757	if (fa) {
3758		ifp = XFS_IFORK_PTR(ip, XFS_ATTR_FORK);
3759		xfs_inode_verifier_error(ip, -EFSCORRUPTED, "attr fork",
3760				ifp ? ifp->if_u1.if_data : NULL,
3761				ifp ? ifp->if_bytes : 0, fa);
3762		return false;
3763	}
3764	return true;
3765}
3766
3767STATIC int
3768xfs_iflush_int(
3769	struct xfs_inode	*ip,
3770	struct xfs_buf		*bp)
3771{
3772	struct xfs_inode_log_item *iip = ip->i_itemp;
3773	struct xfs_dinode	*dip;
3774	struct xfs_mount	*mp = ip->i_mount;
 
 
 
3775
3776	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3777	ASSERT(xfs_isiflocked(ip));
3778	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3779	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3780	ASSERT(iip != NULL && iip->ili_fields != 0);
3781	ASSERT(ip->i_d.di_version > 1);
 
3782
3783	/* set *dip = inode's place in the buffer */
3784	dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3785
3786	if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3787			       mp, XFS_ERRTAG_IFLUSH_1)) {
3788		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3789			"%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT,
3790			__func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3791		goto corrupt_out;
3792	}
3793	if (S_ISREG(VFS_I(ip)->i_mode)) {
 
 
 
 
 
 
 
3794		if (XFS_TEST_ERROR(
3795		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3796		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3797		    mp, XFS_ERRTAG_IFLUSH_3)) {
3798			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3799				"%s: Bad regular inode %Lu, ptr "PTR_FMT,
3800				__func__, ip->i_ino, ip);
3801			goto corrupt_out;
3802		}
3803	} else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3804		if (XFS_TEST_ERROR(
3805		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3806		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3807		    (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3808		    mp, XFS_ERRTAG_IFLUSH_4)) {
3809			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3810				"%s: Bad directory inode %Lu, ptr "PTR_FMT,
3811				__func__, ip->i_ino, ip);
3812			goto corrupt_out;
3813		}
3814	}
3815	if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3816				ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
 
3817		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3818			"%s: detected corrupt incore inode %Lu, "
3819			"total extents = %d, nblocks = %Ld, ptr "PTR_FMT,
3820			__func__, ip->i_ino,
3821			ip->i_d.di_nextents + ip->i_d.di_anextents,
3822			ip->i_d.di_nblocks, ip);
3823		goto corrupt_out;
3824	}
3825	if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3826				mp, XFS_ERRTAG_IFLUSH_6)) {
3827		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3828			"%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT,
3829			__func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3830		goto corrupt_out;
3831	}
3832
3833	/*
3834	 * Inode item log recovery for v2 inodes are dependent on the
3835	 * di_flushiter count for correct sequencing. We bump the flush
3836	 * iteration count so we can detect flushes which postdate a log record
3837	 * during recovery. This is redundant as we now log every change and
3838	 * hence this can't happen but we need to still do it to ensure
3839	 * backwards compatibility with old kernels that predate logging all
3840	 * inode changes.
3841	 */
3842	if (ip->i_d.di_version < 3)
3843		ip->i_d.di_flushiter++;
3844
3845	/* Check the inline fork data before we write out. */
3846	if (!xfs_inode_verify_forks(ip))
3847		goto corrupt_out;
3848
3849	/*
3850	 * Copy the dirty parts of the inode into the on-disk inode.  We always
3851	 * copy out the core of the inode, because if the inode is dirty at all
3852	 * the core must be.
 
3853	 */
3854	xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3855
3856	/* Wrap, we never let the log put out DI_MAX_FLUSH */
3857	if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3858		ip->i_d.di_flushiter = 0;
3859
3860	xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3861	if (XFS_IFORK_Q(ip))
3862		xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3863	xfs_inobp_check(mp, bp);
3864
3865	/*
3866	 * We've recorded everything logged in the inode, so we'd like to clear
3867	 * the ili_fields bits so we don't log and flush things unnecessarily.
3868	 * However, we can't stop logging all this information until the data
3869	 * we've copied into the disk buffer is written to disk.  If we did we
3870	 * might overwrite the copy of the inode in the log with all the data
3871	 * after re-logging only part of it, and in the face of a crash we
3872	 * wouldn't have all the data we need to recover.
3873	 *
3874	 * What we do is move the bits to the ili_last_fields field.  When
3875	 * logging the inode, these bits are moved back to the ili_fields field.
3876	 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3877	 * know that the information those bits represent is permanently on
3878	 * disk.  As long as the flush completes before the inode is logged
3879	 * again, then both ili_fields and ili_last_fields will be cleared.
3880	 *
3881	 * We can play with the ili_fields bits here, because the inode lock
3882	 * must be held exclusively in order to set bits there and the flush
3883	 * lock protects the ili_last_fields bits.  Set ili_logged so the flush
3884	 * done routine can tell whether or not to look in the AIL.  Also, store
3885	 * the current LSN of the inode so that we can tell whether the item has
3886	 * moved in the AIL from xfs_iflush_done().  In order to read the lsn we
3887	 * need the AIL lock, because it is a 64 bit value that cannot be read
3888	 * atomically.
3889	 */
3890	iip->ili_last_fields = iip->ili_fields;
3891	iip->ili_fields = 0;
3892	iip->ili_fsync_fields = 0;
3893	iip->ili_logged = 1;
3894
3895	xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3896				&iip->ili_item.li_lsn);
3897
3898	/*
3899	 * Attach the function xfs_iflush_done to the inode's
3900	 * buffer.  This will remove the inode from the AIL
3901	 * and unlock the inode's flush lock when the inode is
3902	 * completely written to disk.
3903	 */
3904	xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3905
3906	/* generate the checksum. */
3907	xfs_dinode_calc_crc(mp, dip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3908
3909	ASSERT(!list_empty(&bp->b_li_list));
3910	ASSERT(bp->b_iodone != NULL);
3911	return 0;
3912
3913corrupt_out:
3914	return -EFSCORRUPTED;
3915}
3916
3917/* Release an inode. */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3918void
3919xfs_irele(
3920	struct xfs_inode	*ip)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3921{
3922	trace_xfs_irele(ip, _RET_IP_);
3923	iput(VFS_I(ip));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3924}
v3.5.6
 
   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_types.h"
  23#include "xfs_log.h"
  24#include "xfs_inum.h"
  25#include "xfs_trans.h"
  26#include "xfs_trans_priv.h"
  27#include "xfs_sb.h"
  28#include "xfs_ag.h"
  29#include "xfs_mount.h"
  30#include "xfs_bmap_btree.h"
  31#include "xfs_alloc_btree.h"
  32#include "xfs_ialloc_btree.h"
  33#include "xfs_attr_sf.h"
  34#include "xfs_dinode.h"
  35#include "xfs_inode.h"
 
 
 
 
  36#include "xfs_buf_item.h"
  37#include "xfs_inode_item.h"
  38#include "xfs_btree.h"
  39#include "xfs_alloc.h"
  40#include "xfs_ialloc.h"
  41#include "xfs_bmap.h"
 
 
  42#include "xfs_error.h"
  43#include "xfs_utils.h"
  44#include "xfs_quota.h"
  45#include "xfs_filestream.h"
  46#include "xfs_vnodeops.h"
  47#include "xfs_trace.h"
 
 
 
 
 
 
  48
  49kmem_zone_t *xfs_ifork_zone;
  50kmem_zone_t *xfs_inode_zone;
  51
  52/*
  53 * Used in xfs_itruncate_extents().  This is the maximum number of extents
  54 * freed from a file in a single transaction.
  55 */
  56#define	XFS_ITRUNC_MAX_EXTENTS	2
  57
  58STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *);
  59STATIC int xfs_iformat_local(xfs_inode_t *, xfs_dinode_t *, int, int);
  60STATIC int xfs_iformat_extents(xfs_inode_t *, xfs_dinode_t *, int);
  61STATIC int xfs_iformat_btree(xfs_inode_t *, xfs_dinode_t *, int);
  62
  63/*
  64 * helper function to extract extent size hint from inode
  65 */
  66xfs_extlen_t
  67xfs_get_extsz_hint(
  68	struct xfs_inode	*ip)
  69{
  70	if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
  71		return ip->i_d.di_extsize;
  72	if (XFS_IS_REALTIME_INODE(ip))
  73		return ip->i_mount->m_sb.sb_rextsize;
  74	return 0;
  75}
  76
  77#ifdef DEBUG
  78/*
  79 * Make sure that the extents in the given memory buffer
  80 * are valid.
 
 
  81 */
  82STATIC void
  83xfs_validate_extents(
  84	xfs_ifork_t		*ifp,
  85	int			nrecs,
  86	xfs_exntfmt_t		fmt)
  87{
  88	xfs_bmbt_irec_t		irec;
  89	xfs_bmbt_rec_host_t	rec;
  90	int			i;
  91
  92	for (i = 0; i < nrecs; i++) {
  93		xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
  94		rec.l0 = get_unaligned(&ep->l0);
  95		rec.l1 = get_unaligned(&ep->l1);
  96		xfs_bmbt_get_all(&rec, &irec);
  97		if (fmt == XFS_EXTFMT_NOSTATE)
  98			ASSERT(irec.br_state == XFS_EXT_NORM);
  99	}
 
 100}
 101#else /* DEBUG */
 102#define xfs_validate_extents(ifp, nrecs, fmt)
 103#endif /* DEBUG */
 104
 105/*
 106 * Check that none of the inode's in the buffer have a next
 107 * unlinked field of 0.
 
 
 
 
 
 
 
 
 
 
 
 108 */
 109#if defined(DEBUG)
 110void
 111xfs_inobp_check(
 112	xfs_mount_t	*mp,
 113	xfs_buf_t	*bp)
 114{
 115	int		i;
 116	int		j;
 117	xfs_dinode_t	*dip;
 118
 119	j = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
 120
 121	for (i = 0; i < j; i++) {
 122		dip = (xfs_dinode_t *)xfs_buf_offset(bp,
 123					i * mp->m_sb.sb_inodesize);
 124		if (!dip->di_next_unlinked)  {
 125			xfs_alert(mp,
 126	"Detected bogus zero next_unlinked field in incore inode buffer 0x%p.",
 127				bp);
 128			ASSERT(dip->di_next_unlinked);
 129		}
 130	}
 
 
 131}
 132#endif
 133
 134/*
 135 * Find the buffer associated with the given inode map
 136 * We do basic validation checks on the buffer once it has been
 137 * retrieved from disk.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 138 */
 139STATIC int
 140xfs_imap_to_bp(
 141	xfs_mount_t	*mp,
 142	xfs_trans_t	*tp,
 143	struct xfs_imap	*imap,
 144	xfs_buf_t	**bpp,
 145	uint		buf_flags,
 146	uint		iget_flags)
 147{
 148	int		error;
 149	int		i;
 150	int		ni;
 151	xfs_buf_t	*bp;
 152
 153	buf_flags |= XBF_UNMAPPED;
 154	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
 155				   (int)imap->im_len, buf_flags, &bp);
 156	if (error) {
 157		if (error != EAGAIN) {
 158			xfs_warn(mp,
 159				"%s: xfs_trans_read_buf() returned error %d.",
 160				__func__, error);
 161		} else {
 162			ASSERT(buf_flags & XBF_TRYLOCK);
 163		}
 164		return error;
 165	}
 166
 167	/*
 168	 * Validate the magic number and version of every inode in the buffer
 169	 * (if DEBUG kernel) or the first inode in the buffer, otherwise.
 
 170	 */
 171#ifdef DEBUG
 172	ni = BBTOB(imap->im_len) >> mp->m_sb.sb_inodelog;
 173#else	/* usual case */
 174	ni = 1;
 175#endif
 
 
 176
 177	for (i = 0; i < ni; i++) {
 178		int		di_ok;
 179		xfs_dinode_t	*dip;
 180
 181		dip = (xfs_dinode_t *)xfs_buf_offset(bp,
 182					(i << mp->m_sb.sb_inodelog));
 183		di_ok = dip->di_magic == cpu_to_be16(XFS_DINODE_MAGIC) &&
 184			    XFS_DINODE_GOOD_VERSION(dip->di_version);
 185		if (unlikely(XFS_TEST_ERROR(!di_ok, mp,
 186						XFS_ERRTAG_ITOBP_INOTOBP,
 187						XFS_RANDOM_ITOBP_INOTOBP))) {
 188			if (iget_flags & XFS_IGET_UNTRUSTED) {
 189				xfs_trans_brelse(tp, bp);
 190				return XFS_ERROR(EINVAL);
 191			}
 192			XFS_CORRUPTION_ERROR("xfs_imap_to_bp",
 193						XFS_ERRLEVEL_HIGH, mp, dip);
 194#ifdef DEBUG
 195			xfs_emerg(mp,
 196				"bad inode magic/vsn daddr %lld #%d (magic=%x)",
 197				(unsigned long long)imap->im_blkno, i,
 198				be16_to_cpu(dip->di_magic));
 199			ASSERT(0);
 200#endif
 201			xfs_trans_brelse(tp, bp);
 202			return XFS_ERROR(EFSCORRUPTED);
 203		}
 204	}
 205
 206	xfs_inobp_check(mp, bp);
 207	*bpp = bp;
 208	return 0;
 
 
 
 
 
 
 209}
 210
 211/*
 212 * This routine is called to map an inode number within a file
 213 * system to the buffer containing the on-disk version of the
 214 * inode.  It returns a pointer to the buffer containing the
 215 * on-disk inode in the bpp parameter, and in the dip parameter
 216 * it returns a pointer to the on-disk inode within that buffer.
 217 *
 218 * If a non-zero error is returned, then the contents of bpp and
 219 * dipp are undefined.
 220 *
 221 * Use xfs_imap() to determine the size and location of the
 222 * buffer to read from disk.
 223 */
 224int
 225xfs_inotobp(
 226	xfs_mount_t	*mp,
 227	xfs_trans_t	*tp,
 228	xfs_ino_t	ino,
 229	xfs_dinode_t	**dipp,
 230	xfs_buf_t	**bpp,
 231	int		*offset,
 232	uint		imap_flags)
 233{
 234	struct xfs_imap	imap;
 235	xfs_buf_t	*bp;
 236	int		error;
 237
 238	imap.im_blkno = 0;
 239	error = xfs_imap(mp, tp, ino, &imap, imap_flags);
 240	if (error)
 241		return error;
 
 
 
 
 
 
 
 
 242
 243	error = xfs_imap_to_bp(mp, tp, &imap, &bp, 0, imap_flags);
 244	if (error)
 245		return error;
 
 
 
 
 246
 247	*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
 248	*bpp = bp;
 249	*offset = imap.im_boffset;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 250	return 0;
 251}
 252
 253
 254/*
 255 * This routine is called to map an inode to the buffer containing
 256 * the on-disk version of the inode.  It returns a pointer to the
 257 * buffer containing the on-disk inode in the bpp parameter, and in
 258 * the dip parameter it returns a pointer to the on-disk inode within
 259 * that buffer.
 260 *
 261 * If a non-zero error is returned, then the contents of bpp and
 262 * dipp are undefined.
 
 
 263 *
 264 * The inode is expected to already been mapped to its buffer and read
 265 * in once, thus we can use the mapping information stored in the inode
 266 * rather than calling xfs_imap().  This allows us to avoid the overhead
 267 * of looking at the inode btree for small block file systems
 268 * (see xfs_imap()).
 269 */
 270int
 271xfs_itobp(
 272	xfs_mount_t	*mp,
 273	xfs_trans_t	*tp,
 274	xfs_inode_t	*ip,
 275	xfs_dinode_t	**dipp,
 276	xfs_buf_t	**bpp,
 277	uint		buf_flags)
 278{
 279	xfs_buf_t	*bp;
 280	int		error;
 
 
 
 
 
 
 
 
 
 
 
 281
 282	ASSERT(ip->i_imap.im_blkno != 0);
 
 
 
 283
 284	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp, buf_flags, 0);
 285	if (error)
 286		return error;
 
 287
 288	if (!bp) {
 289		ASSERT(buf_flags & XBF_TRYLOCK);
 290		ASSERT(tp == NULL);
 291		*bpp = NULL;
 292		return EAGAIN;
 293	}
 294
 295	*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
 296	*bpp = bp;
 297	return 0;
 298}
 299
 300/*
 301 * Move inode type and inode format specific information from the
 302 * on-disk inode to the in-core inode.  For fifos, devs, and sockets
 303 * this means set if_rdev to the proper value.  For files, directories,
 304 * and symlinks this means to bring in the in-line data or extent
 305 * pointers.  For a file in B-tree format, only the root is immediately
 306 * brought in-core.  The rest will be in-lined in if_extents when it
 307 * is first referenced (see xfs_iread_extents()).
 308 */
 309STATIC int
 310xfs_iformat(
 311	xfs_inode_t		*ip,
 312	xfs_dinode_t		*dip)
 313{
 314	xfs_attr_shortform_t	*atp;
 315	int			size;
 316	int			error = 0;
 317	xfs_fsize_t             di_size;
 318
 319	if (unlikely(be32_to_cpu(dip->di_nextents) +
 320		     be16_to_cpu(dip->di_anextents) >
 321		     be64_to_cpu(dip->di_nblocks))) {
 322		xfs_warn(ip->i_mount,
 323			"corrupt dinode %Lu, extent total = %d, nblocks = %Lu.",
 324			(unsigned long long)ip->i_ino,
 325			(int)(be32_to_cpu(dip->di_nextents) +
 326			      be16_to_cpu(dip->di_anextents)),
 327			(unsigned long long)
 328				be64_to_cpu(dip->di_nblocks));
 329		XFS_CORRUPTION_ERROR("xfs_iformat(1)", XFS_ERRLEVEL_LOW,
 330				     ip->i_mount, dip);
 331		return XFS_ERROR(EFSCORRUPTED);
 332	}
 333
 334	if (unlikely(dip->di_forkoff > ip->i_mount->m_sb.sb_inodesize)) {
 335		xfs_warn(ip->i_mount, "corrupt dinode %Lu, forkoff = 0x%x.",
 336			(unsigned long long)ip->i_ino,
 337			dip->di_forkoff);
 338		XFS_CORRUPTION_ERROR("xfs_iformat(2)", XFS_ERRLEVEL_LOW,
 339				     ip->i_mount, dip);
 340		return XFS_ERROR(EFSCORRUPTED);
 341	}
 342
 343	if (unlikely((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) &&
 344		     !ip->i_mount->m_rtdev_targp)) {
 345		xfs_warn(ip->i_mount,
 346			"corrupt dinode %Lu, has realtime flag set.",
 347			ip->i_ino);
 348		XFS_CORRUPTION_ERROR("xfs_iformat(realtime)",
 349				     XFS_ERRLEVEL_LOW, ip->i_mount, dip);
 350		return XFS_ERROR(EFSCORRUPTED);
 351	}
 352
 353	switch (ip->i_d.di_mode & S_IFMT) {
 354	case S_IFIFO:
 355	case S_IFCHR:
 356	case S_IFBLK:
 357	case S_IFSOCK:
 358		if (unlikely(dip->di_format != XFS_DINODE_FMT_DEV)) {
 359			XFS_CORRUPTION_ERROR("xfs_iformat(3)", XFS_ERRLEVEL_LOW,
 360					      ip->i_mount, dip);
 361			return XFS_ERROR(EFSCORRUPTED);
 362		}
 363		ip->i_d.di_size = 0;
 364		ip->i_df.if_u2.if_rdev = xfs_dinode_get_rdev(dip);
 365		break;
 366
 367	case S_IFREG:
 368	case S_IFLNK:
 369	case S_IFDIR:
 370		switch (dip->di_format) {
 371		case XFS_DINODE_FMT_LOCAL:
 372			/*
 373			 * no local regular files yet
 374			 */
 375			if (unlikely(S_ISREG(be16_to_cpu(dip->di_mode)))) {
 376				xfs_warn(ip->i_mount,
 377			"corrupt inode %Lu (local format for regular file).",
 378					(unsigned long long) ip->i_ino);
 379				XFS_CORRUPTION_ERROR("xfs_iformat(4)",
 380						     XFS_ERRLEVEL_LOW,
 381						     ip->i_mount, dip);
 382				return XFS_ERROR(EFSCORRUPTED);
 383			}
 384
 385			di_size = be64_to_cpu(dip->di_size);
 386			if (unlikely(di_size > XFS_DFORK_DSIZE(dip, ip->i_mount))) {
 387				xfs_warn(ip->i_mount,
 388			"corrupt inode %Lu (bad size %Ld for local inode).",
 389					(unsigned long long) ip->i_ino,
 390					(long long) di_size);
 391				XFS_CORRUPTION_ERROR("xfs_iformat(5)",
 392						     XFS_ERRLEVEL_LOW,
 393						     ip->i_mount, dip);
 394				return XFS_ERROR(EFSCORRUPTED);
 395			}
 396
 397			size = (int)di_size;
 398			error = xfs_iformat_local(ip, dip, XFS_DATA_FORK, size);
 399			break;
 400		case XFS_DINODE_FMT_EXTENTS:
 401			error = xfs_iformat_extents(ip, dip, XFS_DATA_FORK);
 402			break;
 403		case XFS_DINODE_FMT_BTREE:
 404			error = xfs_iformat_btree(ip, dip, XFS_DATA_FORK);
 405			break;
 406		default:
 407			XFS_ERROR_REPORT("xfs_iformat(6)", XFS_ERRLEVEL_LOW,
 408					 ip->i_mount);
 409			return XFS_ERROR(EFSCORRUPTED);
 410		}
 411		break;
 412
 413	default:
 414		XFS_ERROR_REPORT("xfs_iformat(7)", XFS_ERRLEVEL_LOW, ip->i_mount);
 415		return XFS_ERROR(EFSCORRUPTED);
 416	}
 417	if (error) {
 418		return error;
 419	}
 420	if (!XFS_DFORK_Q(dip))
 421		return 0;
 422
 423	ASSERT(ip->i_afp == NULL);
 424	ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP | KM_NOFS);
 425
 426	switch (dip->di_aformat) {
 427	case XFS_DINODE_FMT_LOCAL:
 428		atp = (xfs_attr_shortform_t *)XFS_DFORK_APTR(dip);
 429		size = be16_to_cpu(atp->hdr.totsize);
 430
 431		if (unlikely(size < sizeof(struct xfs_attr_sf_hdr))) {
 432			xfs_warn(ip->i_mount,
 433				"corrupt inode %Lu (bad attr fork size %Ld).",
 434				(unsigned long long) ip->i_ino,
 435				(long long) size);
 436			XFS_CORRUPTION_ERROR("xfs_iformat(8)",
 437					     XFS_ERRLEVEL_LOW,
 438					     ip->i_mount, dip);
 439			return XFS_ERROR(EFSCORRUPTED);
 440		}
 441
 442		error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, size);
 443		break;
 444	case XFS_DINODE_FMT_EXTENTS:
 445		error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK);
 446		break;
 447	case XFS_DINODE_FMT_BTREE:
 448		error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK);
 449		break;
 450	default:
 451		error = XFS_ERROR(EFSCORRUPTED);
 452		break;
 453	}
 454	if (error) {
 455		kmem_zone_free(xfs_ifork_zone, ip->i_afp);
 456		ip->i_afp = NULL;
 457		xfs_idestroy_fork(ip, XFS_DATA_FORK);
 458	}
 459	return error;
 460}
 
 461
 462/*
 463 * The file is in-lined in the on-disk inode.
 464 * If it fits into if_inline_data, then copy
 465 * it there, otherwise allocate a buffer for it
 466 * and copy the data there.  Either way, set
 467 * if_data to point at the data.
 468 * If we allocate a buffer for the data, make
 469 * sure that its size is a multiple of 4 and
 470 * record the real size in i_real_bytes.
 471 */
 472STATIC int
 473xfs_iformat_local(
 474	xfs_inode_t	*ip,
 475	xfs_dinode_t	*dip,
 476	int		whichfork,
 477	int		size)
 478{
 479	xfs_ifork_t	*ifp;
 480	int		real_size;
 481
 482	/*
 483	 * If the size is unreasonable, then something
 484	 * is wrong and we just bail out rather than crash in
 485	 * kmem_alloc() or memcpy() below.
 486	 */
 487	if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
 488		xfs_warn(ip->i_mount,
 489	"corrupt inode %Lu (bad size %d for local fork, size = %d).",
 490			(unsigned long long) ip->i_ino, size,
 491			XFS_DFORK_SIZE(dip, ip->i_mount, whichfork));
 492		XFS_CORRUPTION_ERROR("xfs_iformat_local", XFS_ERRLEVEL_LOW,
 493				     ip->i_mount, dip);
 494		return XFS_ERROR(EFSCORRUPTED);
 495	}
 496	ifp = XFS_IFORK_PTR(ip, whichfork);
 497	real_size = 0;
 498	if (size == 0)
 499		ifp->if_u1.if_data = NULL;
 500	else if (size <= sizeof(ifp->if_u2.if_inline_data))
 501		ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
 502	else {
 503		real_size = roundup(size, 4);
 504		ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP | KM_NOFS);
 505	}
 506	ifp->if_bytes = size;
 507	ifp->if_real_bytes = real_size;
 508	if (size)
 509		memcpy(ifp->if_u1.if_data, XFS_DFORK_PTR(dip, whichfork), size);
 510	ifp->if_flags &= ~XFS_IFEXTENTS;
 511	ifp->if_flags |= XFS_IFINLINE;
 512	return 0;
 513}
 
 
 
 514
 515/*
 516 * The file consists of a set of extents all
 517 * of which fit into the on-disk inode.
 518 * If there are few enough extents to fit into
 519 * the if_inline_ext, then copy them there.
 520 * Otherwise allocate a buffer for them and copy
 521 * them into it.  Either way, set if_extents
 522 * to point at the extents.
 523 */
 524STATIC int
 525xfs_iformat_extents(
 526	xfs_inode_t	*ip,
 527	xfs_dinode_t	*dip,
 528	int		whichfork)
 529{
 530	xfs_bmbt_rec_t	*dp;
 531	xfs_ifork_t	*ifp;
 532	int		nex;
 533	int		size;
 534	int		i;
 
 
 535
 536	ifp = XFS_IFORK_PTR(ip, whichfork);
 537	nex = XFS_DFORK_NEXTENTS(dip, whichfork);
 538	size = nex * (uint)sizeof(xfs_bmbt_rec_t);
 
 539
 540	/*
 541	 * If the number of extents is unreasonable, then something
 542	 * is wrong and we just bail out rather than crash in
 543	 * kmem_alloc() or memcpy() below.
 544	 */
 545	if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
 546		xfs_warn(ip->i_mount, "corrupt inode %Lu ((a)extents = %d).",
 547			(unsigned long long) ip->i_ino, nex);
 548		XFS_CORRUPTION_ERROR("xfs_iformat_extents(1)", XFS_ERRLEVEL_LOW,
 549				     ip->i_mount, dip);
 550		return XFS_ERROR(EFSCORRUPTED);
 551	}
 552
 553	ifp->if_real_bytes = 0;
 554	if (nex == 0)
 555		ifp->if_u1.if_extents = NULL;
 556	else if (nex <= XFS_INLINE_EXTS)
 557		ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
 558	else
 559		xfs_iext_add(ifp, 0, nex);
 560
 561	ifp->if_bytes = size;
 562	if (size) {
 563		dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork);
 564		xfs_validate_extents(ifp, nex, XFS_EXTFMT_INODE(ip));
 565		for (i = 0; i < nex; i++, dp++) {
 566			xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
 567			ep->l0 = get_unaligned_be64(&dp->l0);
 568			ep->l1 = get_unaligned_be64(&dp->l1);
 569		}
 570		XFS_BMAP_TRACE_EXLIST(ip, nex, whichfork);
 571		if (whichfork != XFS_DATA_FORK ||
 572			XFS_EXTFMT_INODE(ip) == XFS_EXTFMT_NOSTATE)
 573				if (unlikely(xfs_check_nostate_extents(
 574				    ifp, 0, nex))) {
 575					XFS_ERROR_REPORT("xfs_iformat_extents(2)",
 576							 XFS_ERRLEVEL_LOW,
 577							 ip->i_mount);
 578					return XFS_ERROR(EFSCORRUPTED);
 579				}
 580	}
 581	ifp->if_flags |= XFS_IFEXTENTS;
 582	return 0;
 583}
 584
 585/*
 586 * The file has too many extents to fit into
 587 * the inode, so they are in B-tree format.
 588 * Allocate a buffer for the root of the B-tree
 589 * and copy the root into it.  The i_extents
 590 * field will remain NULL until all of the
 591 * extents are read in (when they are needed).
 
 
 
 
 
 
 
 592 */
 593STATIC int
 594xfs_iformat_btree(
 595	xfs_inode_t		*ip,
 596	xfs_dinode_t		*dip,
 597	int			whichfork)
 598{
 599	xfs_bmdr_block_t	*dfp;
 600	xfs_ifork_t		*ifp;
 601	/* REFERENCED */
 602	int			nrecs;
 603	int			size;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 604
 605	ifp = XFS_IFORK_PTR(ip, whichfork);
 606	dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork);
 607	size = XFS_BMAP_BROOT_SPACE(dfp);
 608	nrecs = be16_to_cpu(dfp->bb_numrecs);
 609
 610	/*
 611	 * blow out if -- fork has less extents than can fit in
 612	 * fork (fork shouldn't be a btree format), root btree
 613	 * block has more records than can fit into the fork,
 614	 * or the number of extents is greater than the number of
 615	 * blocks.
 616	 */
 617	if (unlikely(XFS_IFORK_NEXTENTS(ip, whichfork) <=
 618			XFS_IFORK_MAXEXT(ip, whichfork) ||
 619		     XFS_BMDR_SPACE_CALC(nrecs) >
 620			XFS_DFORK_SIZE(dip, ip->i_mount, whichfork) ||
 621		     XFS_IFORK_NEXTENTS(ip, whichfork) > ip->i_d.di_nblocks)) {
 622		xfs_warn(ip->i_mount, "corrupt inode %Lu (btree).",
 623			(unsigned long long) ip->i_ino);
 624		XFS_CORRUPTION_ERROR("xfs_iformat_btree", XFS_ERRLEVEL_LOW,
 625				 ip->i_mount, dip);
 626		return XFS_ERROR(EFSCORRUPTED);
 627	}
 628
 629	ifp->if_broot_bytes = size;
 630	ifp->if_broot = kmem_alloc(size, KM_SLEEP | KM_NOFS);
 631	ASSERT(ifp->if_broot != NULL);
 632	/*
 633	 * Copy and convert from the on-disk structure
 634	 * to the in-memory structure.
 635	 */
 636	xfs_bmdr_to_bmbt(ip->i_mount, dfp,
 637			 XFS_DFORK_SIZE(dip, ip->i_mount, whichfork),
 638			 ifp->if_broot, size);
 639	ifp->if_flags &= ~XFS_IFEXTENTS;
 640	ifp->if_flags |= XFS_IFBROOT;
 641
 642	return 0;
 
 
 
 
 
 
 643}
 644
 645STATIC void
 646xfs_dinode_from_disk(
 647	xfs_icdinode_t		*to,
 648	xfs_dinode_t		*from)
 649{
 650	to->di_magic = be16_to_cpu(from->di_magic);
 651	to->di_mode = be16_to_cpu(from->di_mode);
 652	to->di_version = from ->di_version;
 653	to->di_format = from->di_format;
 654	to->di_onlink = be16_to_cpu(from->di_onlink);
 655	to->di_uid = be32_to_cpu(from->di_uid);
 656	to->di_gid = be32_to_cpu(from->di_gid);
 657	to->di_nlink = be32_to_cpu(from->di_nlink);
 658	to->di_projid_lo = be16_to_cpu(from->di_projid_lo);
 659	to->di_projid_hi = be16_to_cpu(from->di_projid_hi);
 660	memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
 661	to->di_flushiter = be16_to_cpu(from->di_flushiter);
 662	to->di_atime.t_sec = be32_to_cpu(from->di_atime.t_sec);
 663	to->di_atime.t_nsec = be32_to_cpu(from->di_atime.t_nsec);
 664	to->di_mtime.t_sec = be32_to_cpu(from->di_mtime.t_sec);
 665	to->di_mtime.t_nsec = be32_to_cpu(from->di_mtime.t_nsec);
 666	to->di_ctime.t_sec = be32_to_cpu(from->di_ctime.t_sec);
 667	to->di_ctime.t_nsec = be32_to_cpu(from->di_ctime.t_nsec);
 668	to->di_size = be64_to_cpu(from->di_size);
 669	to->di_nblocks = be64_to_cpu(from->di_nblocks);
 670	to->di_extsize = be32_to_cpu(from->di_extsize);
 671	to->di_nextents = be32_to_cpu(from->di_nextents);
 672	to->di_anextents = be16_to_cpu(from->di_anextents);
 673	to->di_forkoff = from->di_forkoff;
 674	to->di_aformat	= from->di_aformat;
 675	to->di_dmevmask	= be32_to_cpu(from->di_dmevmask);
 676	to->di_dmstate	= be16_to_cpu(from->di_dmstate);
 677	to->di_flags	= be16_to_cpu(from->di_flags);
 678	to->di_gen	= be32_to_cpu(from->di_gen);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 679}
 680
 681void
 682xfs_dinode_to_disk(
 683	xfs_dinode_t		*to,
 684	xfs_icdinode_t		*from)
 685{
 686	to->di_magic = cpu_to_be16(from->di_magic);
 687	to->di_mode = cpu_to_be16(from->di_mode);
 688	to->di_version = from ->di_version;
 689	to->di_format = from->di_format;
 690	to->di_onlink = cpu_to_be16(from->di_onlink);
 691	to->di_uid = cpu_to_be32(from->di_uid);
 692	to->di_gid = cpu_to_be32(from->di_gid);
 693	to->di_nlink = cpu_to_be32(from->di_nlink);
 694	to->di_projid_lo = cpu_to_be16(from->di_projid_lo);
 695	to->di_projid_hi = cpu_to_be16(from->di_projid_hi);
 696	memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
 697	to->di_flushiter = cpu_to_be16(from->di_flushiter);
 698	to->di_atime.t_sec = cpu_to_be32(from->di_atime.t_sec);
 699	to->di_atime.t_nsec = cpu_to_be32(from->di_atime.t_nsec);
 700	to->di_mtime.t_sec = cpu_to_be32(from->di_mtime.t_sec);
 701	to->di_mtime.t_nsec = cpu_to_be32(from->di_mtime.t_nsec);
 702	to->di_ctime.t_sec = cpu_to_be32(from->di_ctime.t_sec);
 703	to->di_ctime.t_nsec = cpu_to_be32(from->di_ctime.t_nsec);
 704	to->di_size = cpu_to_be64(from->di_size);
 705	to->di_nblocks = cpu_to_be64(from->di_nblocks);
 706	to->di_extsize = cpu_to_be32(from->di_extsize);
 707	to->di_nextents = cpu_to_be32(from->di_nextents);
 708	to->di_anextents = cpu_to_be16(from->di_anextents);
 709	to->di_forkoff = from->di_forkoff;
 710	to->di_aformat = from->di_aformat;
 711	to->di_dmevmask = cpu_to_be32(from->di_dmevmask);
 712	to->di_dmstate = cpu_to_be16(from->di_dmstate);
 713	to->di_flags = cpu_to_be16(from->di_flags);
 714	to->di_gen = cpu_to_be32(from->di_gen);
 715}
 716
 717STATIC uint
 718_xfs_dic2xflags(
 719	__uint16_t		di_flags)
 
 
 720{
 721	uint			flags = 0;
 722
 723	if (di_flags & XFS_DIFLAG_ANY) {
 724		if (di_flags & XFS_DIFLAG_REALTIME)
 725			flags |= XFS_XFLAG_REALTIME;
 726		if (di_flags & XFS_DIFLAG_PREALLOC)
 727			flags |= XFS_XFLAG_PREALLOC;
 728		if (di_flags & XFS_DIFLAG_IMMUTABLE)
 729			flags |= XFS_XFLAG_IMMUTABLE;
 730		if (di_flags & XFS_DIFLAG_APPEND)
 731			flags |= XFS_XFLAG_APPEND;
 732		if (di_flags & XFS_DIFLAG_SYNC)
 733			flags |= XFS_XFLAG_SYNC;
 734		if (di_flags & XFS_DIFLAG_NOATIME)
 735			flags |= XFS_XFLAG_NOATIME;
 736		if (di_flags & XFS_DIFLAG_NODUMP)
 737			flags |= XFS_XFLAG_NODUMP;
 738		if (di_flags & XFS_DIFLAG_RTINHERIT)
 739			flags |= XFS_XFLAG_RTINHERIT;
 740		if (di_flags & XFS_DIFLAG_PROJINHERIT)
 741			flags |= XFS_XFLAG_PROJINHERIT;
 742		if (di_flags & XFS_DIFLAG_NOSYMLINKS)
 743			flags |= XFS_XFLAG_NOSYMLINKS;
 744		if (di_flags & XFS_DIFLAG_EXTSIZE)
 745			flags |= XFS_XFLAG_EXTSIZE;
 746		if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
 747			flags |= XFS_XFLAG_EXTSZINHERIT;
 748		if (di_flags & XFS_DIFLAG_NODEFRAG)
 749			flags |= XFS_XFLAG_NODEFRAG;
 750		if (di_flags & XFS_DIFLAG_FILESTREAM)
 751			flags |= XFS_XFLAG_FILESTREAM;
 
 
 
 
 
 
 
 752	}
 753
 
 
 
 754	return flags;
 755}
 756
 757uint
 758xfs_ip2xflags(
 759	xfs_inode_t		*ip)
 760{
 761	xfs_icdinode_t		*dic = &ip->i_d;
 762
 763	return _xfs_dic2xflags(dic->di_flags) |
 764				(XFS_IFORK_Q(ip) ? XFS_XFLAG_HASATTR : 0);
 765}
 766
 767uint
 768xfs_dic2xflags(
 769	xfs_dinode_t		*dip)
 770{
 771	return _xfs_dic2xflags(be16_to_cpu(dip->di_flags)) |
 772				(XFS_DFORK_Q(dip) ? XFS_XFLAG_HASATTR : 0);
 773}
 774
 775/*
 776 * Read the disk inode attributes into the in-core inode structure.
 
 
 
 777 */
 778int
 779xfs_iread(
 780	xfs_mount_t	*mp,
 781	xfs_trans_t	*tp,
 782	xfs_inode_t	*ip,
 783	uint		iget_flags)
 784{
 785	xfs_buf_t	*bp;
 786	xfs_dinode_t	*dip;
 787	int		error;
 
 
 
 
 788
 789	/*
 790	 * Fill in the location information in the in-core inode.
 791	 */
 792	error = xfs_imap(mp, tp, ip->i_ino, &ip->i_imap, iget_flags);
 793	if (error)
 794		return error;
 795
 796	/*
 797	 * Get pointers to the on-disk inode and the buffer containing it.
 798	 */
 799	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp, 0, iget_flags);
 800	if (error)
 801		return error;
 802	dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
 803
 804	/*
 805	 * If we got something that isn't an inode it means someone
 806	 * (nfs or dmi) has a stale handle.
 807	 */
 808	if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC)) {
 809#ifdef DEBUG
 810		xfs_alert(mp,
 811			"%s: dip->di_magic (0x%x) != XFS_DINODE_MAGIC (0x%x)",
 812			__func__, be16_to_cpu(dip->di_magic), XFS_DINODE_MAGIC);
 813#endif /* DEBUG */
 814		error = XFS_ERROR(EINVAL);
 815		goto out_brelse;
 816	}
 817
 818	/*
 819	 * If the on-disk inode is already linked to a directory
 820	 * entry, copy all of the inode into the in-core inode.
 821	 * xfs_iformat() handles copying in the inode format
 822	 * specific information.
 823	 * Otherwise, just get the truly permanent information.
 824	 */
 825	if (dip->di_mode) {
 826		xfs_dinode_from_disk(&ip->i_d, dip);
 827		error = xfs_iformat(ip, dip);
 828		if (error)  {
 829#ifdef DEBUG
 830			xfs_alert(mp, "%s: xfs_iformat() returned error %d",
 831				__func__, error);
 832#endif /* DEBUG */
 833			goto out_brelse;
 834		}
 835	} else {
 836		ip->i_d.di_magic = be16_to_cpu(dip->di_magic);
 837		ip->i_d.di_version = dip->di_version;
 838		ip->i_d.di_gen = be32_to_cpu(dip->di_gen);
 839		ip->i_d.di_flushiter = be16_to_cpu(dip->di_flushiter);
 840		/*
 841		 * Make sure to pull in the mode here as well in
 842		 * case the inode is released without being used.
 843		 * This ensures that xfs_inactive() will see that
 844		 * the inode is already free and not try to mess
 845		 * with the uninitialized part of it.
 846		 */
 847		ip->i_d.di_mode = 0;
 848	}
 849
 850	/*
 851	 * The inode format changed when we moved the link count and
 852	 * made it 32 bits long.  If this is an old format inode,
 853	 * convert it in memory to look like a new one.  If it gets
 854	 * flushed to disk we will convert back before flushing or
 855	 * logging it.  We zero out the new projid field and the old link
 856	 * count field.  We'll handle clearing the pad field (the remains
 857	 * of the old uuid field) when we actually convert the inode to
 858	 * the new format. We don't change the version number so that we
 859	 * can distinguish this from a real new format inode.
 860	 */
 861	if (ip->i_d.di_version == 1) {
 862		ip->i_d.di_nlink = ip->i_d.di_onlink;
 863		ip->i_d.di_onlink = 0;
 864		xfs_set_projid(ip, 0);
 865	}
 866
 867	ip->i_delayed_blks = 0;
 868
 869	/*
 870	 * Mark the buffer containing the inode as something to keep
 871	 * around for a while.  This helps to keep recently accessed
 872	 * meta-data in-core longer.
 873	 */
 874	xfs_buf_set_ref(bp, XFS_INO_REF);
 875
 876	/*
 877	 * Use xfs_trans_brelse() to release the buffer containing the
 878	 * on-disk inode, because it was acquired with xfs_trans_read_buf()
 879	 * in xfs_itobp() above.  If tp is NULL, this is just a normal
 880	 * brelse().  If we're within a transaction, then xfs_trans_brelse()
 881	 * will only release the buffer if it is not dirty within the
 882	 * transaction.  It will be OK to release the buffer in this case,
 883	 * because inodes on disk are never destroyed and we will be
 884	 * locking the new in-core inode before putting it in the hash
 885	 * table where other processes can find it.  Thus we don't have
 886	 * to worry about the inode being changed just because we released
 887	 * the buffer.
 888	 */
 889 out_brelse:
 890	xfs_trans_brelse(tp, bp);
 891	return error;
 892}
 893
 894/*
 895 * Read in extents from a btree-format inode.
 896 * Allocate and fill in if_extents.  Real work is done in xfs_bmap.c.
 897 */
 898int
 899xfs_iread_extents(
 900	xfs_trans_t	*tp,
 901	xfs_inode_t	*ip,
 902	int		whichfork)
 903{
 904	int		error;
 905	xfs_ifork_t	*ifp;
 906	xfs_extnum_t	nextents;
 907
 908	if (unlikely(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
 909		XFS_ERROR_REPORT("xfs_iread_extents", XFS_ERRLEVEL_LOW,
 910				 ip->i_mount);
 911		return XFS_ERROR(EFSCORRUPTED);
 912	}
 913	nextents = XFS_IFORK_NEXTENTS(ip, whichfork);
 914	ifp = XFS_IFORK_PTR(ip, whichfork);
 915
 916	/*
 917	 * We know that the size is valid (it's checked in iformat_btree)
 918	 */
 919	ifp->if_bytes = ifp->if_real_bytes = 0;
 920	ifp->if_flags |= XFS_IFEXTENTS;
 921	xfs_iext_add(ifp, 0, nextents);
 922	error = xfs_bmap_read_extents(tp, ip, whichfork);
 923	if (error) {
 924		xfs_iext_destroy(ifp);
 925		ifp->if_flags &= ~XFS_IFEXTENTS;
 926		return error;
 927	}
 928	xfs_validate_extents(ifp, nextents, XFS_EXTFMT_INODE(ip));
 929	return 0;
 930}
 931
 932/*
 933 * Allocate an inode on disk and return a copy of its in-core version.
 934 * The in-core inode is locked exclusively.  Set mode, nlink, and rdev
 935 * appropriately within the inode.  The uid and gid for the inode are
 936 * set according to the contents of the given cred structure.
 937 *
 938 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
 939 * has a free inode available, call xfs_iget()
 940 * to obtain the in-core version of the allocated inode.  Finally,
 941 * fill in the inode and log its initial contents.  In this case,
 942 * ialloc_context would be set to NULL and call_again set to false.
 943 *
 944 * If xfs_dialloc() does not have an available inode,
 945 * it will replenish its supply by doing an allocation. Since we can
 946 * only do one allocation within a transaction without deadlocks, we
 947 * must commit the current transaction before returning the inode itself.
 948 * In this case, therefore, we will set call_again to true and return.
 949 * The caller should then commit the current transaction, start a new
 950 * transaction, and call xfs_ialloc() again to actually get the inode.
 951 *
 952 * To ensure that some other process does not grab the inode that
 953 * was allocated during the first call to xfs_ialloc(), this routine
 954 * also returns the [locked] bp pointing to the head of the freelist
 955 * as ialloc_context.  The caller should hold this buffer across
 956 * the commit and pass it back into this routine on the second call.
 957 *
 958 * If we are allocating quota inodes, we do not have a parent inode
 959 * to attach to or associate with (i.e. pip == NULL) because they
 960 * are not linked into the directory structure - they are attached
 961 * directly to the superblock - and so have no parent.
 962 */
 963int
 964xfs_ialloc(
 965	xfs_trans_t	*tp,
 966	xfs_inode_t	*pip,
 967	umode_t		mode,
 968	xfs_nlink_t	nlink,
 969	xfs_dev_t	rdev,
 970	prid_t		prid,
 971	int		okalloc,
 972	xfs_buf_t	**ialloc_context,
 973	boolean_t	*call_again,
 974	xfs_inode_t	**ipp)
 975{
 
 976	xfs_ino_t	ino;
 977	xfs_inode_t	*ip;
 978	uint		flags;
 979	int		error;
 980	timespec_t	tv;
 981	int		filestreams = 0;
 982
 983	/*
 984	 * Call the space management code to pick
 985	 * the on-disk inode to be allocated.
 986	 */
 987	error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
 988			    ialloc_context, call_again, &ino);
 989	if (error)
 990		return error;
 991	if (*call_again || ino == NULLFSINO) {
 992		*ipp = NULL;
 993		return 0;
 994	}
 995	ASSERT(*ialloc_context == NULL);
 996
 997	/*
 
 
 
 
 
 
 
 
 
 
 
 
 998	 * Get the in-core inode with the lock held exclusively.
 999	 * This is because we're setting fields here we need
1000	 * to prevent others from looking at until we're done.
1001	 */
1002	error = xfs_iget(tp->t_mountp, tp, ino, XFS_IGET_CREATE,
1003			 XFS_ILOCK_EXCL, &ip);
1004	if (error)
1005		return error;
1006	ASSERT(ip != NULL);
1007
1008	ip->i_d.di_mode = mode;
1009	ip->i_d.di_onlink = 0;
1010	ip->i_d.di_nlink = nlink;
1011	ASSERT(ip->i_d.di_nlink == nlink);
1012	ip->i_d.di_uid = current_fsuid();
1013	ip->i_d.di_gid = current_fsgid();
1014	xfs_set_projid(ip, prid);
1015	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
1016
1017	/*
1018	 * If the superblock version is up to where we support new format
1019	 * inodes and this is currently an old format inode, then change
1020	 * the inode version number now.  This way we only do the conversion
1021	 * here rather than here and in the flush/logging code.
1022	 */
1023	if (xfs_sb_version_hasnlink(&tp->t_mountp->m_sb) &&
1024	    ip->i_d.di_version == 1) {
1025		ip->i_d.di_version = 2;
1026		/*
1027		 * We've already zeroed the old link count, the projid field,
1028		 * and the pad field.
1029		 */
1030	}
1031
1032	/*
1033	 * Project ids won't be stored on disk if we are using a version 1 inode.
1034	 */
1035	if ((prid != 0) && (ip->i_d.di_version == 1))
1036		xfs_bump_ino_vers2(tp, ip);
 
1037
1038	if (pip && XFS_INHERIT_GID(pip)) {
1039		ip->i_d.di_gid = pip->i_d.di_gid;
1040		if ((pip->i_d.di_mode & S_ISGID) && S_ISDIR(mode)) {
1041			ip->i_d.di_mode |= S_ISGID;
1042		}
1043	}
1044
1045	/*
1046	 * If the group ID of the new file does not match the effective group
1047	 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
1048	 * (and only if the irix_sgid_inherit compatibility variable is set).
1049	 */
1050	if ((irix_sgid_inherit) &&
1051	    (ip->i_d.di_mode & S_ISGID) &&
1052	    (!in_group_p((gid_t)ip->i_d.di_gid))) {
1053		ip->i_d.di_mode &= ~S_ISGID;
1054	}
1055
1056	ip->i_d.di_size = 0;
1057	ip->i_d.di_nextents = 0;
1058	ASSERT(ip->i_d.di_nblocks == 0);
1059
1060	nanotime(&tv);
1061	ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec;
1062	ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec;
1063	ip->i_d.di_atime = ip->i_d.di_mtime;
1064	ip->i_d.di_ctime = ip->i_d.di_mtime;
1065
1066	/*
1067	 * di_gen will have been taken care of in xfs_iread.
1068	 */
1069	ip->i_d.di_extsize = 0;
1070	ip->i_d.di_dmevmask = 0;
1071	ip->i_d.di_dmstate = 0;
1072	ip->i_d.di_flags = 0;
 
 
 
 
 
 
 
 
 
 
1073	flags = XFS_ILOG_CORE;
1074	switch (mode & S_IFMT) {
1075	case S_IFIFO:
1076	case S_IFCHR:
1077	case S_IFBLK:
1078	case S_IFSOCK:
1079		ip->i_d.di_format = XFS_DINODE_FMT_DEV;
1080		ip->i_df.if_u2.if_rdev = rdev;
1081		ip->i_df.if_flags = 0;
1082		flags |= XFS_ILOG_DEV;
1083		break;
1084	case S_IFREG:
1085		/*
1086		 * we can't set up filestreams until after the VFS inode
1087		 * is set up properly.
1088		 */
1089		if (pip && xfs_inode_is_filestream(pip))
1090			filestreams = 1;
1091		/* fall through */
1092	case S_IFDIR:
1093		if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
1094			uint	di_flags = 0;
1095
1096			if (S_ISDIR(mode)) {
1097				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
1098					di_flags |= XFS_DIFLAG_RTINHERIT;
1099				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
1100					di_flags |= XFS_DIFLAG_EXTSZINHERIT;
1101					ip->i_d.di_extsize = pip->i_d.di_extsize;
1102				}
 
 
1103			} else if (S_ISREG(mode)) {
1104				if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
1105					di_flags |= XFS_DIFLAG_REALTIME;
1106				if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
1107					di_flags |= XFS_DIFLAG_EXTSIZE;
1108					ip->i_d.di_extsize = pip->i_d.di_extsize;
1109				}
1110			}
1111			if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
1112			    xfs_inherit_noatime)
1113				di_flags |= XFS_DIFLAG_NOATIME;
1114			if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
1115			    xfs_inherit_nodump)
1116				di_flags |= XFS_DIFLAG_NODUMP;
1117			if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
1118			    xfs_inherit_sync)
1119				di_flags |= XFS_DIFLAG_SYNC;
1120			if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
1121			    xfs_inherit_nosymlinks)
1122				di_flags |= XFS_DIFLAG_NOSYMLINKS;
1123			if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
1124				di_flags |= XFS_DIFLAG_PROJINHERIT;
1125			if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
1126			    xfs_inherit_nodefrag)
1127				di_flags |= XFS_DIFLAG_NODEFRAG;
1128			if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
1129				di_flags |= XFS_DIFLAG_FILESTREAM;
 
1130			ip->i_d.di_flags |= di_flags;
1131		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1132		/* FALLTHROUGH */
1133	case S_IFLNK:
1134		ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
1135		ip->i_df.if_flags = XFS_IFEXTENTS;
1136		ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
1137		ip->i_df.if_u1.if_extents = NULL;
1138		break;
1139	default:
1140		ASSERT(0);
1141	}
1142	/*
1143	 * Attribute fork settings for new inode.
1144	 */
1145	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
1146	ip->i_d.di_anextents = 0;
1147
1148	/*
1149	 * Log the new values stuffed into the inode.
1150	 */
1151	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1152	xfs_trans_log_inode(tp, ip, flags);
1153
1154	/* now that we have an i_mode we can setup inode ops and unlock */
1155	xfs_setup_inode(ip);
1156
1157	/* now we have set up the vfs inode we can associate the filestream */
1158	if (filestreams) {
1159		error = xfs_filestream_associate(pip, ip);
1160		if (error < 0)
1161			return -error;
1162		if (!error)
1163			xfs_iflags_set(ip, XFS_IFILESTREAM);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1164	}
1165
1166	*ipp = ip;
 
 
1167	return 0;
1168}
1169
1170/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1171 * Free up the underlying blocks past new_size.  The new size must be smaller
1172 * than the current size.  This routine can be used both for the attribute and
1173 * data fork, and does not modify the inode size, which is left to the caller.
1174 *
1175 * The transaction passed to this routine must have made a permanent log
1176 * reservation of at least XFS_ITRUNCATE_LOG_RES.  This routine may commit the
1177 * given transaction and start new ones, so make sure everything involved in
1178 * the transaction is tidy before calling here.  Some transaction will be
1179 * returned to the caller to be committed.  The incoming transaction must
1180 * already include the inode, and both inode locks must be held exclusively.
1181 * The inode must also be "held" within the transaction.  On return the inode
1182 * will be "held" within the returned transaction.  This routine does NOT
1183 * require any disk space to be reserved for it within the transaction.
1184 *
1185 * If we get an error, we must return with the inode locked and linked into the
1186 * current transaction. This keeps things simple for the higher level code,
1187 * because it always knows that the inode is locked and held in the transaction
1188 * that returns to it whether errors occur or not.  We don't mark the inode
1189 * dirty on error so that transactions can be easily aborted if possible.
1190 */
1191int
1192xfs_itruncate_extents(
1193	struct xfs_trans	**tpp,
1194	struct xfs_inode	*ip,
1195	int			whichfork,
1196	xfs_fsize_t		new_size)
 
1197{
1198	struct xfs_mount	*mp = ip->i_mount;
1199	struct xfs_trans	*tp = *tpp;
1200	struct xfs_trans	*ntp;
1201	xfs_bmap_free_t		free_list;
1202	xfs_fsblock_t		first_block;
1203	xfs_fileoff_t		first_unmap_block;
1204	xfs_fileoff_t		last_block;
1205	xfs_filblks_t		unmap_len;
1206	int			committed;
1207	int			error = 0;
1208	int			done = 0;
1209
1210	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
 
 
1211	ASSERT(new_size <= XFS_ISIZE(ip));
1212	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1213	ASSERT(ip->i_itemp != NULL);
1214	ASSERT(ip->i_itemp->ili_lock_flags == 0);
1215	ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1216
1217	trace_xfs_itruncate_extents_start(ip, new_size);
1218
 
 
1219	/*
1220	 * Since it is possible for space to become allocated beyond
1221	 * the end of the file (in a crash where the space is allocated
1222	 * but the inode size is not yet updated), simply remove any
1223	 * blocks which show up between the new EOF and the maximum
1224	 * possible file size.  If the first block to be removed is
1225	 * beyond the maximum file size (ie it is the same as last_block),
1226	 * then there is nothing to do.
1227	 */
1228	first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1229	last_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
1230	if (first_unmap_block == last_block)
1231		return 0;
1232
1233	ASSERT(first_unmap_block < last_block);
1234	unmap_len = last_block - first_unmap_block + 1;
1235	while (!done) {
1236		xfs_bmap_init(&free_list, &first_block);
1237		error = xfs_bunmapi(tp, ip,
1238				    first_unmap_block, unmap_len,
1239				    xfs_bmapi_aflag(whichfork),
1240				    XFS_ITRUNC_MAX_EXTENTS,
1241				    &first_block, &free_list,
1242				    &done);
1243		if (error)
1244			goto out_bmap_cancel;
1245
1246		/*
1247		 * Duplicate the transaction that has the permanent
1248		 * reservation and commit the old transaction.
1249		 */
1250		error = xfs_bmap_finish(&tp, &free_list, &committed);
1251		if (committed)
1252			xfs_trans_ijoin(tp, ip, 0);
1253		if (error)
1254			goto out_bmap_cancel;
1255
1256		if (committed) {
1257			/*
1258			 * Mark the inode dirty so it will be logged and
1259			 * moved forward in the log as part of every commit.
1260			 */
1261			xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1262		}
1263
1264		ntp = xfs_trans_dup(tp);
1265		error = xfs_trans_commit(tp, 0);
1266		tp = ntp;
1267
1268		xfs_trans_ijoin(tp, ip, 0);
1269
 
1270		if (error)
1271			goto out;
 
1272
1273		/*
1274		 * Transaction commit worked ok so we can drop the extra ticket
1275		 * reference that we gained in xfs_trans_dup()
1276		 */
1277		xfs_log_ticket_put(tp->t_ticket);
1278		error = xfs_trans_reserve(tp, 0,
1279					XFS_ITRUNCATE_LOG_RES(mp), 0,
1280					XFS_TRANS_PERM_LOG_RES,
1281					XFS_ITRUNCATE_LOG_COUNT);
1282		if (error)
1283			goto out;
 
 
1284	}
1285
1286	/*
1287	 * Always re-log the inode so that our permanent transaction can keep
1288	 * on rolling it forward in the log.
1289	 */
1290	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1291
1292	trace_xfs_itruncate_extents_end(ip, new_size);
1293
1294out:
1295	*tpp = tp;
1296	return error;
1297out_bmap_cancel:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1298	/*
1299	 * If the bunmapi call encounters an error, return to the caller where
1300	 * the transaction can be properly aborted.  We just need to make sure
1301	 * we're not holding any resources that we were not when we came in.
1302	 */
1303	xfs_bmap_cancel(&free_list);
1304	goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1305}
1306
1307/*
1308 * This is called when the inode's link count goes to 0.
1309 * We place the on-disk inode on a list in the AGI.  It
1310 * will be pulled from this list when the inode is freed.
1311 */
1312int
1313xfs_iunlink(
1314	xfs_trans_t	*tp,
1315	xfs_inode_t	*ip)
1316{
1317	xfs_mount_t	*mp;
1318	xfs_agi_t	*agi;
1319	xfs_dinode_t	*dip;
1320	xfs_buf_t	*agibp;
1321	xfs_buf_t	*ibp;
1322	xfs_agino_t	agino;
1323	short		bucket_index;
1324	int		offset;
1325	int		error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1326
1327	ASSERT(ip->i_d.di_nlink == 0);
1328	ASSERT(ip->i_d.di_mode != 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1329
1330	mp = tp->t_mountp;
 
 
 
1331
1332	/*
1333	 * Get the agi buffer first.  It ensures lock ordering
1334	 * on the list.
1335	 */
1336	error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
1337	if (error)
1338		return error;
1339	agi = XFS_BUF_TO_AGI(agibp);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1340
1341	/*
1342	 * Get the index into the agi hash table for the
1343	 * list this inode will go on.
1344	 */
1345	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
1346	ASSERT(agino != 0);
1347	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
1348	ASSERT(agi->agi_unlinked[bucket_index]);
1349	ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
1350
1351	if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
1352		/*
1353		 * There is already another inode in the bucket we need
1354		 * to add ourselves to.  Add us at the front of the list.
1355		 * Here we put the head pointer into our next pointer,
1356		 * and then we fall through to point the head at us.
 
 
 
 
 
 
 
 
 
 
 
 
 
1357		 */
1358		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1359		if (error)
1360			return error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1361
1362		ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
1363		dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
1364		offset = ip->i_imap.im_boffset +
1365			offsetof(xfs_dinode_t, di_next_unlinked);
1366		xfs_trans_inode_buf(tp, ibp);
1367		xfs_trans_log_buf(tp, ibp, offset,
1368				  (offset + sizeof(xfs_agino_t) - 1));
1369		xfs_inobp_check(mp, ibp);
 
 
 
1370	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1371
1372	/*
1373	 * Point the bucket head pointer at the inode being inserted.
1374	 */
1375	ASSERT(agino != 0);
1376	agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
1377	offset = offsetof(xfs_agi_t, agi_unlinked) +
1378		(sizeof(xfs_agino_t) * bucket_index);
1379	xfs_trans_log_buf(tp, agibp, offset,
1380			  (offset + sizeof(xfs_agino_t) - 1));
1381	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1382}
1383
1384/*
1385 * Pull the on-disk inode from the AGI unlinked list.
 
1386 */
1387STATIC int
1388xfs_iunlink_remove(
1389	xfs_trans_t	*tp,
1390	xfs_inode_t	*ip)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1391{
1392	xfs_ino_t	next_ino;
1393	xfs_mount_t	*mp;
1394	xfs_agi_t	*agi;
1395	xfs_dinode_t	*dip;
1396	xfs_buf_t	*agibp;
1397	xfs_buf_t	*ibp;
1398	xfs_agnumber_t	agno;
1399	xfs_agino_t	agino;
1400	xfs_agino_t	next_agino;
1401	xfs_buf_t	*last_ibp;
1402	xfs_dinode_t	*last_dip = NULL;
1403	short		bucket_index;
1404	int		offset, last_offset = 0;
1405	int		error;
1406
1407	mp = tp->t_mountp;
1408	agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
 
 
 
 
1409
1410	/*
1411	 * Get the agi buffer first.  It ensures lock ordering
1412	 * on the list.
 
1413	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1414	error = xfs_read_agi(mp, tp, agno, &agibp);
1415	if (error)
1416		return error;
1417
1418	agi = XFS_BUF_TO_AGI(agibp);
1419
1420	/*
1421	 * Get the index into the agi hash table for the
1422	 * list this inode will go on.
 
1423	 */
1424	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
1425	ASSERT(agino != 0);
1426	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
1427	ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
1428	ASSERT(agi->agi_unlinked[bucket_index]);
1429
1430	if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
1431		/*
1432		 * We're at the head of the list.  Get the inode's
1433		 * on-disk buffer to see if there is anyone after us
1434		 * on the list.  Only modify our next pointer if it
1435		 * is not already NULLAGINO.  This saves us the overhead
1436		 * of dealing with the buffer when there is no need to
1437		 * change it.
1438		 */
1439		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
1440		if (error) {
1441			xfs_warn(mp, "%s: xfs_itobp() returned error %d.",
1442				__func__, error);
1443			return error;
1444		}
1445		next_agino = be32_to_cpu(dip->di_next_unlinked);
1446		ASSERT(next_agino != 0);
1447		if (next_agino != NULLAGINO) {
1448			dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
1449			offset = ip->i_imap.im_boffset +
1450				offsetof(xfs_dinode_t, di_next_unlinked);
1451			xfs_trans_inode_buf(tp, ibp);
1452			xfs_trans_log_buf(tp, ibp, offset,
1453					  (offset + sizeof(xfs_agino_t) - 1));
1454			xfs_inobp_check(mp, ibp);
1455		} else {
1456			xfs_trans_brelse(tp, ibp);
1457		}
1458		/*
1459		 * Point the bucket head pointer at the next inode.
 
1460		 */
1461		ASSERT(next_agino != 0);
1462		ASSERT(next_agino != agino);
1463		agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
1464		offset = offsetof(xfs_agi_t, agi_unlinked) +
1465			(sizeof(xfs_agino_t) * bucket_index);
1466		xfs_trans_log_buf(tp, agibp, offset,
1467				  (offset + sizeof(xfs_agino_t) - 1));
1468	} else {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1469		/*
1470		 * We need to search the list for the inode being freed.
 
1471		 */
1472		next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
1473		last_ibp = NULL;
1474		while (next_agino != agino) {
1475			/*
1476			 * If the last inode wasn't the one pointing to
1477			 * us, then release its buffer since we're not
1478			 * going to do anything with it.
1479			 */
1480			if (last_ibp != NULL) {
1481				xfs_trans_brelse(tp, last_ibp);
1482			}
1483			next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
1484			error = xfs_inotobp(mp, tp, next_ino, &last_dip,
1485					    &last_ibp, &last_offset, 0);
1486			if (error) {
1487				xfs_warn(mp,
1488					"%s: xfs_inotobp() returned error %d.",
1489					__func__, error);
1490				return error;
1491			}
1492			next_agino = be32_to_cpu(last_dip->di_next_unlinked);
1493			ASSERT(next_agino != NULLAGINO);
1494			ASSERT(next_agino != 0);
1495		}
1496		/*
1497		 * Now last_ibp points to the buffer previous to us on
1498		 * the unlinked list.  Pull us from the list.
1499		 */
1500		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
1501		if (error) {
1502			xfs_warn(mp, "%s: xfs_itobp(2) returned error %d.",
1503				__func__, error);
 
 
1504			return error;
1505		}
1506		next_agino = be32_to_cpu(dip->di_next_unlinked);
1507		ASSERT(next_agino != 0);
1508		ASSERT(next_agino != agino);
1509		if (next_agino != NULLAGINO) {
1510			dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
1511			offset = ip->i_imap.im_boffset +
1512				offsetof(xfs_dinode_t, di_next_unlinked);
1513			xfs_trans_inode_buf(tp, ibp);
1514			xfs_trans_log_buf(tp, ibp, offset,
1515					  (offset + sizeof(xfs_agino_t) - 1));
1516			xfs_inobp_check(mp, ibp);
1517		} else {
1518			xfs_trans_brelse(tp, ibp);
1519		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1520		/*
1521		 * Point the previous inode on the list to the next inode.
 
 
 
 
 
1522		 */
1523		last_dip->di_next_unlinked = cpu_to_be32(next_agino);
1524		ASSERT(next_agino != 0);
1525		offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
1526		xfs_trans_inode_buf(tp, last_ibp);
1527		xfs_trans_log_buf(tp, last_ibp, offset,
1528				  (offset + sizeof(xfs_agino_t) - 1));
1529		xfs_inobp_check(mp, last_ibp);
1530	}
1531	return 0;
 
 
 
 
1532}
1533
1534/*
1535 * A big issue when freeing the inode cluster is is that we _cannot_ skip any
1536 * inodes that are in memory - they all must be marked stale and attached to
1537 * the cluster buffer.
1538 */
1539STATIC int
1540xfs_ifree_cluster(
1541	xfs_inode_t	*free_ip,
1542	xfs_trans_t	*tp,
1543	xfs_ino_t	inum)
1544{
1545	xfs_mount_t		*mp = free_ip->i_mount;
1546	int			blks_per_cluster;
1547	int			nbufs;
1548	int			ninodes;
1549	int			i, j;
 
1550	xfs_daddr_t		blkno;
1551	xfs_buf_t		*bp;
1552	xfs_inode_t		*ip;
1553	xfs_inode_log_item_t	*iip;
1554	xfs_log_item_t		*lip;
1555	struct xfs_perag	*pag;
 
 
1556
 
1557	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
1558	if (mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) {
1559		blks_per_cluster = 1;
1560		ninodes = mp->m_sb.sb_inopblock;
1561		nbufs = XFS_IALLOC_BLOCKS(mp);
1562	} else {
1563		blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) /
1564					mp->m_sb.sb_blocksize;
1565		ninodes = blks_per_cluster * mp->m_sb.sb_inopblock;
1566		nbufs = XFS_IALLOC_BLOCKS(mp) / blks_per_cluster;
1567	}
 
 
 
1568
1569	for (j = 0; j < nbufs; j++, inum += ninodes) {
1570		blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
1571					 XFS_INO_TO_AGBNO(mp, inum));
1572
1573		/*
1574		 * We obtain and lock the backing buffer first in the process
1575		 * here, as we have to ensure that any dirty inode that we
1576		 * can't get the flush lock on is attached to the buffer.
1577		 * If we scan the in-memory inodes first, then buffer IO can
1578		 * complete before we get a lock on it, and hence we may fail
1579		 * to mark all the active inodes on the buffer stale.
1580		 */
1581		bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
1582					mp->m_bsize * blks_per_cluster, 0);
 
1583
1584		if (!bp)
1585			return ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
1586		/*
1587		 * Walk the inodes already attached to the buffer and mark them
1588		 * stale. These will all have the flush locks held, so an
1589		 * in-memory inode walk can't lock them. By marking them all
1590		 * stale first, we will not attempt to lock them in the loop
1591		 * below as the XFS_ISTALE flag will be set.
1592		 */
1593		lip = bp->b_fspriv;
1594		while (lip) {
1595			if (lip->li_type == XFS_LI_INODE) {
1596				iip = (xfs_inode_log_item_t *)lip;
1597				ASSERT(iip->ili_logged == 1);
1598				lip->li_cb = xfs_istale_done;
1599				xfs_trans_ail_copy_lsn(mp->m_ail,
1600							&iip->ili_flush_lsn,
1601							&iip->ili_item.li_lsn);
1602				xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
1603			}
1604			lip = lip->li_bio_list;
1605		}
1606
1607
1608		/*
1609		 * For each inode in memory attempt to add it to the inode
1610		 * buffer and set it up for being staled on buffer IO
1611		 * completion.  This is safe as we've locked out tail pushing
1612		 * and flushing by locking the buffer.
1613		 *
1614		 * We have already marked every inode that was part of a
1615		 * transaction stale above, which means there is no point in
1616		 * even trying to lock them.
1617		 */
1618		for (i = 0; i < ninodes; i++) {
1619retry:
1620			rcu_read_lock();
1621			ip = radix_tree_lookup(&pag->pag_ici_root,
1622					XFS_INO_TO_AGINO(mp, (inum + i)));
1623
1624			/* Inode not in memory, nothing to do */
1625			if (!ip) {
1626				rcu_read_unlock();
1627				continue;
1628			}
1629
1630			/*
1631			 * because this is an RCU protected lookup, we could
1632			 * find a recently freed or even reallocated inode
1633			 * during the lookup. We need to check under the
1634			 * i_flags_lock for a valid inode here. Skip it if it
1635			 * is not valid, the wrong inode or stale.
1636			 */
1637			spin_lock(&ip->i_flags_lock);
1638			if (ip->i_ino != inum + i ||
1639			    __xfs_iflags_test(ip, XFS_ISTALE)) {
1640				spin_unlock(&ip->i_flags_lock);
1641				rcu_read_unlock();
1642				continue;
1643			}
1644			spin_unlock(&ip->i_flags_lock);
1645
1646			/*
1647			 * Don't try to lock/unlock the current inode, but we
1648			 * _cannot_ skip the other inodes that we did not find
1649			 * in the list attached to the buffer and are not
1650			 * already marked stale. If we can't lock it, back off
1651			 * and retry.
1652			 */
1653			if (ip != free_ip &&
1654			    !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
1655				rcu_read_unlock();
1656				delay(1);
1657				goto retry;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1658			}
1659			rcu_read_unlock();
1660
1661			xfs_iflock(ip);
1662			xfs_iflags_set(ip, XFS_ISTALE);
1663
1664			/*
1665			 * we don't need to attach clean inodes or those only
1666			 * with unlogged changes (which we throw away, anyway).
1667			 */
1668			iip = ip->i_itemp;
1669			if (!iip || xfs_inode_clean(ip)) {
1670				ASSERT(ip != free_ip);
1671				xfs_ifunlock(ip);
1672				xfs_iunlock(ip, XFS_ILOCK_EXCL);
1673				continue;
1674			}
1675
1676			iip->ili_last_fields = iip->ili_fields;
1677			iip->ili_fields = 0;
 
1678			iip->ili_logged = 1;
1679			xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
1680						&iip->ili_item.li_lsn);
1681
1682			xfs_buf_attach_iodone(bp, xfs_istale_done,
1683						  &iip->ili_item);
1684
1685			if (ip != free_ip)
1686				xfs_iunlock(ip, XFS_ILOCK_EXCL);
1687		}
1688
1689		xfs_trans_stale_inode_buf(tp, bp);
1690		xfs_trans_binval(tp, bp);
1691	}
1692
1693	xfs_perag_put(pag);
1694	return 0;
1695}
1696
1697/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1698 * This is called to return an inode to the inode free list.
1699 * The inode should already be truncated to 0 length and have
1700 * no pages associated with it.  This routine also assumes that
1701 * the inode is already a part of the transaction.
1702 *
1703 * The on-disk copy of the inode will have been added to the list
1704 * of unlinked inodes in the AGI. We need to remove the inode from
1705 * that list atomically with respect to freeing it here.
1706 */
1707int
1708xfs_ifree(
1709	xfs_trans_t	*tp,
1710	xfs_inode_t	*ip,
1711	xfs_bmap_free_t	*flist)
1712{
1713	int			error;
1714	int			delete;
1715	xfs_ino_t		first_ino;
1716	xfs_dinode_t    	*dip;
1717	xfs_buf_t       	*ibp;
1718
1719	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1720	ASSERT(ip->i_d.di_nlink == 0);
1721	ASSERT(ip->i_d.di_nextents == 0);
1722	ASSERT(ip->i_d.di_anextents == 0);
1723	ASSERT(ip->i_d.di_size == 0 || !S_ISREG(ip->i_d.di_mode));
1724	ASSERT(ip->i_d.di_nblocks == 0);
1725
1726	/*
1727	 * Pull the on-disk inode from the AGI unlinked list.
1728	 */
1729	error = xfs_iunlink_remove(tp, ip);
1730	if (error != 0) {
1731		return error;
1732	}
1733
1734	error = xfs_difree(tp, ip->i_ino, flist, &delete, &first_ino);
1735	if (error != 0) {
1736		return error;
1737	}
1738	ip->i_d.di_mode = 0;		/* mark incore inode as free */
 
 
 
1739	ip->i_d.di_flags = 0;
 
1740	ip->i_d.di_dmevmask = 0;
1741	ip->i_d.di_forkoff = 0;		/* mark the attr fork not in use */
1742	ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
1743	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
 
 
 
 
1744	/*
1745	 * Bump the generation count so no one will be confused
1746	 * by reincarnations of this inode.
1747	 */
1748	ip->i_d.di_gen++;
1749
1750	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1751
1752	error = xfs_itobp(ip->i_mount, tp, ip, &dip, &ibp, 0);
1753	if (error)
1754		return error;
1755
1756        /*
1757	* Clear the on-disk di_mode. This is to prevent xfs_bulkstat
1758	* from picking up this inode when it is reclaimed (its incore state
1759	* initialzed but not flushed to disk yet). The in-core di_mode is
1760	* already cleared  and a corresponding transaction logged.
1761	* The hack here just synchronizes the in-core to on-disk
1762	* di_mode value in advance before the actual inode sync to disk.
1763	* This is OK because the inode is already unlinked and would never
1764	* change its di_mode again for this inode generation.
1765	* This is a temporary hack that would require a proper fix
1766	* in the future.
1767	*/
1768	dip->di_mode = 0;
1769
1770	if (delete) {
1771		error = xfs_ifree_cluster(ip, tp, first_ino);
1772	}
1773
1774	return error;
1775}
1776
1777/*
1778 * Reallocate the space for if_broot based on the number of records
1779 * being added or deleted as indicated in rec_diff.  Move the records
1780 * and pointers in if_broot to fit the new size.  When shrinking this
1781 * will eliminate holes between the records and pointers created by
1782 * the caller.  When growing this will create holes to be filled in
1783 * by the caller.
1784 *
1785 * The caller must not request to add more records than would fit in
1786 * the on-disk inode root.  If the if_broot is currently NULL, then
1787 * if we adding records one will be allocated.  The caller must also
1788 * not request that the number of records go below zero, although
1789 * it can go to zero.
1790 *
1791 * ip -- the inode whose if_broot area is changing
1792 * ext_diff -- the change in the number of records, positive or negative,
1793 *	 requested for the if_broot array.
1794 */
1795void
1796xfs_iroot_realloc(
1797	xfs_inode_t		*ip,
1798	int			rec_diff,
1799	int			whichfork)
1800{
1801	struct xfs_mount	*mp = ip->i_mount;
1802	int			cur_max;
1803	xfs_ifork_t		*ifp;
1804	struct xfs_btree_block	*new_broot;
1805	int			new_max;
1806	size_t			new_size;
1807	char			*np;
1808	char			*op;
1809
1810	/*
1811	 * Handle the degenerate case quietly.
1812	 */
1813	if (rec_diff == 0) {
1814		return;
1815	}
1816
1817	ifp = XFS_IFORK_PTR(ip, whichfork);
1818	if (rec_diff > 0) {
1819		/*
1820		 * If there wasn't any memory allocated before, just
1821		 * allocate it now and get out.
1822		 */
1823		if (ifp->if_broot_bytes == 0) {
1824			new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(rec_diff);
1825			ifp->if_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS);
1826			ifp->if_broot_bytes = (int)new_size;
1827			return;
1828		}
1829
1830		/*
1831		 * If there is already an existing if_broot, then we need
1832		 * to realloc() it and shift the pointers to their new
1833		 * location.  The records don't change location because
1834		 * they are kept butted up against the btree block header.
1835		 */
1836		cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
1837		new_max = cur_max + rec_diff;
1838		new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(new_max);
1839		ifp->if_broot = kmem_realloc(ifp->if_broot, new_size,
1840				(size_t)XFS_BMAP_BROOT_SPACE_CALC(cur_max), /* old size */
1841				KM_SLEEP | KM_NOFS);
1842		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
1843						     ifp->if_broot_bytes);
1844		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
1845						     (int)new_size);
1846		ifp->if_broot_bytes = (int)new_size;
1847		ASSERT(ifp->if_broot_bytes <=
1848			XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ);
1849		memmove(np, op, cur_max * (uint)sizeof(xfs_dfsbno_t));
1850		return;
1851	}
1852
1853	/*
1854	 * rec_diff is less than 0.  In this case, we are shrinking the
1855	 * if_broot buffer.  It must already exist.  If we go to zero
1856	 * records, just get rid of the root and clear the status bit.
1857	 */
1858	ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0));
1859	cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
1860	new_max = cur_max + rec_diff;
1861	ASSERT(new_max >= 0);
1862	if (new_max > 0)
1863		new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(new_max);
1864	else
1865		new_size = 0;
1866	if (new_size > 0) {
1867		new_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS);
1868		/*
1869		 * First copy over the btree block header.
1870		 */
1871		memcpy(new_broot, ifp->if_broot, XFS_BTREE_LBLOCK_LEN);
1872	} else {
1873		new_broot = NULL;
1874		ifp->if_flags &= ~XFS_IFBROOT;
1875	}
1876
1877	/*
1878	 * Only copy the records and pointers if there are any.
1879	 */
1880	if (new_max > 0) {
1881		/*
1882		 * First copy the records.
1883		 */
1884		op = (char *)XFS_BMBT_REC_ADDR(mp, ifp->if_broot, 1);
1885		np = (char *)XFS_BMBT_REC_ADDR(mp, new_broot, 1);
1886		memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t));
1887
1888		/*
1889		 * Then copy the pointers.
1890		 */
1891		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
1892						     ifp->if_broot_bytes);
1893		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, new_broot, 1,
1894						     (int)new_size);
1895		memcpy(np, op, new_max * (uint)sizeof(xfs_dfsbno_t));
1896	}
1897	kmem_free(ifp->if_broot);
1898	ifp->if_broot = new_broot;
1899	ifp->if_broot_bytes = (int)new_size;
1900	ASSERT(ifp->if_broot_bytes <=
1901		XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ);
1902	return;
1903}
1904
1905
1906/*
1907 * This is called when the amount of space needed for if_data
1908 * is increased or decreased.  The change in size is indicated by
1909 * the number of bytes that need to be added or deleted in the
1910 * byte_diff parameter.
1911 *
1912 * If the amount of space needed has decreased below the size of the
1913 * inline buffer, then switch to using the inline buffer.  Otherwise,
1914 * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
1915 * to what is needed.
1916 *
1917 * ip -- the inode whose if_data area is changing
1918 * byte_diff -- the change in the number of bytes, positive or negative,
1919 *	 requested for the if_data array.
1920 */
1921void
1922xfs_idata_realloc(
1923	xfs_inode_t	*ip,
1924	int		byte_diff,
1925	int		whichfork)
1926{
1927	xfs_ifork_t	*ifp;
1928	int		new_size;
1929	int		real_size;
1930
1931	if (byte_diff == 0) {
1932		return;
1933	}
1934
1935	ifp = XFS_IFORK_PTR(ip, whichfork);
1936	new_size = (int)ifp->if_bytes + byte_diff;
1937	ASSERT(new_size >= 0);
1938
1939	if (new_size == 0) {
1940		if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
1941			kmem_free(ifp->if_u1.if_data);
1942		}
1943		ifp->if_u1.if_data = NULL;
1944		real_size = 0;
1945	} else if (new_size <= sizeof(ifp->if_u2.if_inline_data)) {
1946		/*
1947		 * If the valid extents/data can fit in if_inline_ext/data,
1948		 * copy them from the malloc'd vector and free it.
1949		 */
1950		if (ifp->if_u1.if_data == NULL) {
1951			ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
1952		} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
1953			ASSERT(ifp->if_real_bytes != 0);
1954			memcpy(ifp->if_u2.if_inline_data, ifp->if_u1.if_data,
1955			      new_size);
1956			kmem_free(ifp->if_u1.if_data);
1957			ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
1958		}
1959		real_size = 0;
1960	} else {
1961		/*
1962		 * Stuck with malloc/realloc.
1963		 * For inline data, the underlying buffer must be
1964		 * a multiple of 4 bytes in size so that it can be
1965		 * logged and stay on word boundaries.  We enforce
1966		 * that here.
1967		 */
1968		real_size = roundup(new_size, 4);
1969		if (ifp->if_u1.if_data == NULL) {
1970			ASSERT(ifp->if_real_bytes == 0);
1971			ifp->if_u1.if_data = kmem_alloc(real_size,
1972							KM_SLEEP | KM_NOFS);
1973		} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
1974			/*
1975			 * Only do the realloc if the underlying size
1976			 * is really changing.
1977			 */
1978			if (ifp->if_real_bytes != real_size) {
1979				ifp->if_u1.if_data =
1980					kmem_realloc(ifp->if_u1.if_data,
1981							real_size,
1982							ifp->if_real_bytes,
1983							KM_SLEEP | KM_NOFS);
1984			}
1985		} else {
1986			ASSERT(ifp->if_real_bytes == 0);
1987			ifp->if_u1.if_data = kmem_alloc(real_size,
1988							KM_SLEEP | KM_NOFS);
1989			memcpy(ifp->if_u1.if_data, ifp->if_u2.if_inline_data,
1990				ifp->if_bytes);
1991		}
1992	}
1993	ifp->if_real_bytes = real_size;
1994	ifp->if_bytes = new_size;
1995	ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
1996}
1997
1998void
1999xfs_idestroy_fork(
2000	xfs_inode_t	*ip,
2001	int		whichfork)
2002{
2003	xfs_ifork_t	*ifp;
2004
2005	ifp = XFS_IFORK_PTR(ip, whichfork);
2006	if (ifp->if_broot != NULL) {
2007		kmem_free(ifp->if_broot);
2008		ifp->if_broot = NULL;
2009	}
2010
2011	/*
2012	 * If the format is local, then we can't have an extents
2013	 * array so just look for an inline data array.  If we're
2014	 * not local then we may or may not have an extents list,
2015	 * so check and free it up if we do.
2016	 */
2017	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
2018		if ((ifp->if_u1.if_data != ifp->if_u2.if_inline_data) &&
2019		    (ifp->if_u1.if_data != NULL)) {
2020			ASSERT(ifp->if_real_bytes != 0);
2021			kmem_free(ifp->if_u1.if_data);
2022			ifp->if_u1.if_data = NULL;
2023			ifp->if_real_bytes = 0;
2024		}
2025	} else if ((ifp->if_flags & XFS_IFEXTENTS) &&
2026		   ((ifp->if_flags & XFS_IFEXTIREC) ||
2027		    ((ifp->if_u1.if_extents != NULL) &&
2028		     (ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext)))) {
2029		ASSERT(ifp->if_real_bytes != 0);
2030		xfs_iext_destroy(ifp);
2031	}
2032	ASSERT(ifp->if_u1.if_extents == NULL ||
2033	       ifp->if_u1.if_extents == ifp->if_u2.if_inline_ext);
2034	ASSERT(ifp->if_real_bytes == 0);
2035	if (whichfork == XFS_ATTR_FORK) {
2036		kmem_zone_free(xfs_ifork_zone, ip->i_afp);
2037		ip->i_afp = NULL;
2038	}
2039}
2040
2041/*
2042 * This is called to unpin an inode.  The caller must have the inode locked
2043 * in at least shared mode so that the buffer cannot be subsequently pinned
2044 * once someone is waiting for it to be unpinned.
2045 */
2046static void
2047xfs_iunpin(
2048	struct xfs_inode	*ip)
2049{
2050	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2051
2052	trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2053
2054	/* Give the log a push to start the unpinning I/O */
2055	xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0);
2056
2057}
2058
2059static void
2060__xfs_iunpin_wait(
2061	struct xfs_inode	*ip)
2062{
2063	wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2064	DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2065
2066	xfs_iunpin(ip);
2067
2068	do {
2069		prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
2070		if (xfs_ipincount(ip))
2071			io_schedule();
2072	} while (xfs_ipincount(ip));
2073	finish_wait(wq, &wait.wait);
2074}
2075
2076void
2077xfs_iunpin_wait(
2078	struct xfs_inode	*ip)
2079{
2080	if (xfs_ipincount(ip))
2081		__xfs_iunpin_wait(ip);
2082}
2083
2084/*
2085 * xfs_iextents_copy()
2086 *
2087 * This is called to copy the REAL extents (as opposed to the delayed
2088 * allocation extents) from the inode into the given buffer.  It
2089 * returns the number of bytes copied into the buffer.
2090 *
2091 * If there are no delayed allocation extents, then we can just
2092 * memcpy() the extents into the buffer.  Otherwise, we need to
2093 * examine each extent in turn and skip those which are delayed.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2094 */
2095int
2096xfs_iextents_copy(
2097	xfs_inode_t		*ip,
2098	xfs_bmbt_rec_t		*dp,
2099	int			whichfork)
2100{
2101	int			copied;
2102	int			i;
2103	xfs_ifork_t		*ifp;
2104	int			nrecs;
2105	xfs_fsblock_t		start_block;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2106
2107	ifp = XFS_IFORK_PTR(ip, whichfork);
2108	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2109	ASSERT(ifp->if_bytes > 0);
2110
2111	nrecs = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
2112	XFS_BMAP_TRACE_EXLIST(ip, nrecs, whichfork);
2113	ASSERT(nrecs > 0);
2114
2115	/*
2116	 * There are some delayed allocation extents in the
2117	 * inode, so copy the extents one at a time and skip
2118	 * the delayed ones.  There must be at least one
2119	 * non-delayed extent.
2120	 */
2121	copied = 0;
2122	for (i = 0; i < nrecs; i++) {
2123		xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
2124		start_block = xfs_bmbt_get_startblock(ep);
2125		if (isnullstartblock(start_block)) {
2126			/*
2127			 * It's a delayed allocation extent, so skip it.
2128			 */
2129			continue;
2130		}
2131
2132		/* Translate to on disk format */
2133		put_unaligned(cpu_to_be64(ep->l0), &dp->l0);
2134		put_unaligned(cpu_to_be64(ep->l1), &dp->l1);
2135		dp++;
2136		copied++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2137	}
2138	ASSERT(copied != 0);
2139	xfs_validate_extents(ifp, copied, XFS_EXTFMT_INODE(ip));
2140
2141	return (copied * (uint)sizeof(xfs_bmbt_rec_t));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2142}
2143
2144/*
2145 * Each of the following cases stores data into the same region
2146 * of the on-disk inode, so only one of them can be valid at
2147 * any given time. While it is possible to have conflicting formats
2148 * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
2149 * in EXTENTS format, this can only happen when the fork has
2150 * changed formats after being modified but before being flushed.
2151 * In these cases, the format always takes precedence, because the
2152 * format indicates the current state of the fork.
2153 */
2154/*ARGSUSED*/
2155STATIC void
2156xfs_iflush_fork(
2157	xfs_inode_t		*ip,
2158	xfs_dinode_t		*dip,
2159	xfs_inode_log_item_t	*iip,
2160	int			whichfork,
2161	xfs_buf_t		*bp)
 
 
2162{
2163	char			*cp;
2164	xfs_ifork_t		*ifp;
2165	xfs_mount_t		*mp;
2166#ifdef XFS_TRANS_DEBUG
2167	int			first;
2168#endif
2169	static const short	brootflag[2] =
2170		{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
2171	static const short	dataflag[2] =
2172		{ XFS_ILOG_DDATA, XFS_ILOG_ADATA };
2173	static const short	extflag[2] =
2174		{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };
2175
2176	if (!iip)
2177		return;
2178	ifp = XFS_IFORK_PTR(ip, whichfork);
2179	/*
2180	 * This can happen if we gave up in iformat in an error path,
2181	 * for the attribute fork.
 
 
 
2182	 */
2183	if (!ifp) {
2184		ASSERT(whichfork == XFS_ATTR_FORK);
2185		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2186	}
2187	cp = XFS_DFORK_PTR(dip, whichfork);
2188	mp = ip->i_mount;
2189	switch (XFS_IFORK_FORMAT(ip, whichfork)) {
2190	case XFS_DINODE_FMT_LOCAL:
2191		if ((iip->ili_fields & dataflag[whichfork]) &&
2192		    (ifp->if_bytes > 0)) {
2193			ASSERT(ifp->if_u1.if_data != NULL);
2194			ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
2195			memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2196		}
2197		break;
2198
2199	case XFS_DINODE_FMT_EXTENTS:
2200		ASSERT((ifp->if_flags & XFS_IFEXTENTS) ||
2201		       !(iip->ili_fields & extflag[whichfork]));
2202		if ((iip->ili_fields & extflag[whichfork]) &&
2203		    (ifp->if_bytes > 0)) {
2204			ASSERT(xfs_iext_get_ext(ifp, 0));
2205			ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) > 0);
2206			(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
2207				whichfork);
 
 
 
 
 
 
 
 
 
 
 
 
 
2208		}
2209		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2210
2211	case XFS_DINODE_FMT_BTREE:
2212		if ((iip->ili_fields & brootflag[whichfork]) &&
2213		    (ifp->if_broot_bytes > 0)) {
2214			ASSERT(ifp->if_broot != NULL);
2215			ASSERT(ifp->if_broot_bytes <=
2216			       (XFS_IFORK_SIZE(ip, whichfork) +
2217				XFS_BROOT_SIZE_ADJ));
2218			xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes,
2219				(xfs_bmdr_block_t *)cp,
2220				XFS_DFORK_SIZE(dip, mp, whichfork));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2221		}
2222		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2223
2224	case XFS_DINODE_FMT_DEV:
2225		if (iip->ili_fields & XFS_ILOG_DEV) {
2226			ASSERT(whichfork == XFS_DATA_FORK);
2227			xfs_dinode_put_rdev(dip, ip->i_df.if_u2.if_rdev);
2228		}
2229		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2230
2231	case XFS_DINODE_FMT_UUID:
2232		if (iip->ili_fields & XFS_ILOG_UUID) {
2233			ASSERT(whichfork == XFS_DATA_FORK);
2234			memcpy(XFS_DFORK_DPTR(dip),
2235			       &ip->i_df.if_u2.if_uuid,
2236			       sizeof(uuid_t));
 
2237		}
2238		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2239
2240	default:
2241		ASSERT(0);
2242		break;
 
 
 
 
2243	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2244}
2245
2246STATIC int
2247xfs_iflush_cluster(
2248	xfs_inode_t	*ip,
2249	xfs_buf_t	*bp)
2250{
2251	xfs_mount_t		*mp = ip->i_mount;
2252	struct xfs_perag	*pag;
2253	unsigned long		first_index, mask;
2254	unsigned long		inodes_per_cluster;
2255	int			ilist_size;
2256	xfs_inode_t		**ilist;
2257	xfs_inode_t		*iq;
2258	int			nr_found;
2259	int			clcount = 0;
2260	int			bufwasdelwri;
2261	int			i;
2262
2263	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2264
2265	inodes_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog;
2266	ilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
2267	ilist = kmem_alloc(ilist_size, KM_MAYFAIL|KM_NOFS);
2268	if (!ilist)
2269		goto out_put;
2270
2271	mask = ~(((XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog)) - 1);
2272	first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
2273	rcu_read_lock();
2274	/* really need a gang lookup range call here */
2275	nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)ilist,
2276					first_index, inodes_per_cluster);
2277	if (nr_found == 0)
2278		goto out_free;
2279
2280	for (i = 0; i < nr_found; i++) {
2281		iq = ilist[i];
2282		if (iq == ip)
2283			continue;
2284
2285		/*
2286		 * because this is an RCU protected lookup, we could find a
2287		 * recently freed or even reallocated inode during the lookup.
2288		 * We need to check under the i_flags_lock for a valid inode
2289		 * here. Skip it if it is not valid or the wrong inode.
2290		 */
2291		spin_lock(&ip->i_flags_lock);
2292		if (!ip->i_ino ||
2293		    (XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) != first_index) {
2294			spin_unlock(&ip->i_flags_lock);
2295			continue;
2296		}
2297		spin_unlock(&ip->i_flags_lock);
 
 
 
 
 
 
 
 
 
 
2298
2299		/*
2300		 * Do an un-protected check to see if the inode is dirty and
2301		 * is a candidate for flushing.  These checks will be repeated
2302		 * later after the appropriate locks are acquired.
2303		 */
2304		if (xfs_inode_clean(iq) && xfs_ipincount(iq) == 0)
2305			continue;
2306
2307		/*
2308		 * Try to get locks.  If any are unavailable or it is pinned,
2309		 * then this inode cannot be flushed and is skipped.
2310		 */
2311
2312		if (!xfs_ilock_nowait(iq, XFS_ILOCK_SHARED))
 
 
 
2313			continue;
2314		if (!xfs_iflock_nowait(iq)) {
2315			xfs_iunlock(iq, XFS_ILOCK_SHARED);
 
 
2316			continue;
2317		}
2318		if (xfs_ipincount(iq)) {
2319			xfs_ifunlock(iq);
2320			xfs_iunlock(iq, XFS_ILOCK_SHARED);
 
 
 
 
 
 
 
 
2321			continue;
2322		}
2323
2324		/*
2325		 * arriving here means that this inode can be flushed.  First
2326		 * re-check that it's dirty before flushing.
2327		 */
2328		if (!xfs_inode_clean(iq)) {
2329			int	error;
2330			error = xfs_iflush_int(iq, bp);
2331			if (error) {
2332				xfs_iunlock(iq, XFS_ILOCK_SHARED);
2333				goto cluster_corrupt_out;
2334			}
2335			clcount++;
2336		} else {
2337			xfs_ifunlock(iq);
2338		}
2339		xfs_iunlock(iq, XFS_ILOCK_SHARED);
2340	}
2341
2342	if (clcount) {
2343		XFS_STATS_INC(xs_icluster_flushcnt);
2344		XFS_STATS_ADD(xs_icluster_flushinode, clcount);
2345	}
2346
2347out_free:
2348	rcu_read_unlock();
2349	kmem_free(ilist);
2350out_put:
2351	xfs_perag_put(pag);
2352	return 0;
2353
2354
2355cluster_corrupt_out:
2356	/*
2357	 * Corruption detected in the clustering loop.  Invalidate the
2358	 * inode buffer and shut down the filesystem.
2359	 */
2360	rcu_read_unlock();
 
2361	/*
2362	 * Clean up the buffer.  If it was delwri, just release it --
2363	 * brelse can handle it with no problems.  If not, shut down the
2364	 * filesystem before releasing the buffer.
2365	 */
2366	bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
2367	if (bufwasdelwri)
2368		xfs_buf_relse(bp);
 
 
 
 
 
2369
2370	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
2371
2372	if (!bufwasdelwri) {
2373		/*
2374		 * Just like incore_relse: if we have b_iodone functions,
2375		 * mark the buffer as an error and call them.  Otherwise
2376		 * mark it as stale and brelse.
2377		 */
2378		if (bp->b_iodone) {
2379			XFS_BUF_UNDONE(bp);
2380			xfs_buf_stale(bp);
2381			xfs_buf_ioerror(bp, EIO);
2382			xfs_buf_ioend(bp, 0);
2383		} else {
2384			xfs_buf_stale(bp);
2385			xfs_buf_relse(bp);
2386		}
2387	}
2388
2389	/*
2390	 * Unlocks the flush lock
2391	 */
2392	xfs_iflush_abort(iq, false);
2393	kmem_free(ilist);
2394	xfs_perag_put(pag);
2395	return XFS_ERROR(EFSCORRUPTED);
2396}
2397
2398/*
2399 * Flush dirty inode metadata into the backing buffer.
2400 *
2401 * The caller must have the inode lock and the inode flush lock held.  The
2402 * inode lock will still be held upon return to the caller, and the inode
2403 * flush lock will be released after the inode has reached the disk.
2404 *
2405 * The caller must write out the buffer returned in *bpp and release it.
2406 */
2407int
2408xfs_iflush(
2409	struct xfs_inode	*ip,
2410	struct xfs_buf		**bpp)
2411{
2412	struct xfs_mount	*mp = ip->i_mount;
2413	struct xfs_buf		*bp;
2414	struct xfs_dinode	*dip;
2415	int			error;
2416
2417	XFS_STATS_INC(xs_iflush_count);
2418
2419	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2420	ASSERT(xfs_isiflocked(ip));
2421	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
2422	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
2423
2424	*bpp = NULL;
2425
2426	xfs_iunpin_wait(ip);
2427
2428	/*
2429	 * For stale inodes we cannot rely on the backing buffer remaining
2430	 * stale in cache for the remaining life of the stale inode and so
2431	 * xfs_itobp() below may give us a buffer that no longer contains
2432	 * inodes below. We have to check this after ensuring the inode is
2433	 * unpinned so that it is safe to reclaim the stale inode after the
2434	 * flush call.
2435	 */
2436	if (xfs_iflags_test(ip, XFS_ISTALE)) {
2437		xfs_ifunlock(ip);
2438		return 0;
2439	}
2440
2441	/*
2442	 * This may have been unpinned because the filesystem is shutting
2443	 * down forcibly. If that's the case we must not write this inode
2444	 * to disk, because the log record didn't make it to disk.
2445	 *
2446	 * We also have to remove the log item from the AIL in this case,
2447	 * as we wait for an empty AIL as part of the unmount process.
2448	 */
2449	if (XFS_FORCED_SHUTDOWN(mp)) {
2450		error = XFS_ERROR(EIO);
2451		goto abort_out;
2452	}
2453
2454	/*
2455	 * Get the buffer containing the on-disk inode.
2456	 */
2457	error = xfs_itobp(mp, NULL, ip, &dip, &bp, XBF_TRYLOCK);
2458	if (error || !bp) {
 
 
 
 
 
 
 
2459		xfs_ifunlock(ip);
2460		return error;
2461	}
 
 
2462
2463	/*
2464	 * First flush out the inode that xfs_iflush was called with.
2465	 */
2466	error = xfs_iflush_int(ip, bp);
2467	if (error)
2468		goto corrupt_out;
2469
2470	/*
2471	 * If the buffer is pinned then push on the log now so we won't
2472	 * get stuck waiting in the write for too long.
2473	 */
2474	if (xfs_buf_ispinned(bp))
2475		xfs_log_force(mp, 0);
2476
2477	/*
2478	 * inode clustering:
2479	 * see if other inodes can be gathered into this write
 
 
 
 
 
2480	 */
2481	error = xfs_iflush_cluster(ip, bp);
2482	if (error)
2483		goto cluster_corrupt_out;
2484
2485	*bpp = bp;
2486	return 0;
2487
2488corrupt_out:
2489	xfs_buf_relse(bp);
 
2490	xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
2491cluster_corrupt_out:
2492	error = XFS_ERROR(EFSCORRUPTED);
2493abort_out:
2494	/*
2495	 * Unlocks the flush lock
2496	 */
2497	xfs_iflush_abort(ip, false);
2498	return error;
2499}
2500
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2501
2502STATIC int
2503xfs_iflush_int(
2504	xfs_inode_t		*ip,
2505	xfs_buf_t		*bp)
2506{
2507	xfs_inode_log_item_t	*iip;
2508	xfs_dinode_t		*dip;
2509	xfs_mount_t		*mp;
2510#ifdef XFS_TRANS_DEBUG
2511	int			first;
2512#endif
2513
2514	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2515	ASSERT(xfs_isiflocked(ip));
2516	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
2517	       ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
2518
2519	iip = ip->i_itemp;
2520	mp = ip->i_mount;
2521
2522	/* set *dip = inode's place in the buffer */
2523	dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
2524
2525	if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
2526			       mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
2527		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
2528			"%s: Bad inode %Lu magic number 0x%x, ptr 0x%p",
2529			__func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
2530		goto corrupt_out;
2531	}
2532	if (XFS_TEST_ERROR(ip->i_d.di_magic != XFS_DINODE_MAGIC,
2533				mp, XFS_ERRTAG_IFLUSH_2, XFS_RANDOM_IFLUSH_2)) {
2534		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
2535			"%s: Bad inode %Lu, ptr 0x%p, magic number 0x%x",
2536			__func__, ip->i_ino, ip, ip->i_d.di_magic);
2537		goto corrupt_out;
2538	}
2539	if (S_ISREG(ip->i_d.di_mode)) {
2540		if (XFS_TEST_ERROR(
2541		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
2542		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
2543		    mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
2544			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
2545				"%s: Bad regular inode %Lu, ptr 0x%p",
2546				__func__, ip->i_ino, ip);
2547			goto corrupt_out;
2548		}
2549	} else if (S_ISDIR(ip->i_d.di_mode)) {
2550		if (XFS_TEST_ERROR(
2551		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
2552		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
2553		    (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
2554		    mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
2555			xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
2556				"%s: Bad directory inode %Lu, ptr 0x%p",
2557				__func__, ip->i_ino, ip);
2558			goto corrupt_out;
2559		}
2560	}
2561	if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
2562				ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
2563				XFS_RANDOM_IFLUSH_5)) {
2564		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
2565			"%s: detected corrupt incore inode %Lu, "
2566			"total extents = %d, nblocks = %Ld, ptr 0x%p",
2567			__func__, ip->i_ino,
2568			ip->i_d.di_nextents + ip->i_d.di_anextents,
2569			ip->i_d.di_nblocks, ip);
2570		goto corrupt_out;
2571	}
2572	if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
2573				mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
2574		xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
2575			"%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
2576			__func__, ip->i_ino, ip->i_d.di_forkoff, ip);
2577		goto corrupt_out;
2578	}
 
2579	/*
2580	 * bump the flush iteration count, used to detect flushes which
2581	 * postdate a log record during recovery.
 
 
 
 
 
2582	 */
 
 
2583
2584	ip->i_d.di_flushiter++;
 
 
2585
2586	/*
2587	 * Copy the dirty parts of the inode into the on-disk
2588	 * inode.  We always copy out the core of the inode,
2589	 * because if the inode is dirty at all the core must
2590	 * be.
2591	 */
2592	xfs_dinode_to_disk(dip, &ip->i_d);
2593
2594	/* Wrap, we never let the log put out DI_MAX_FLUSH */
2595	if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
2596		ip->i_d.di_flushiter = 0;
2597
2598	/*
2599	 * If this is really an old format inode and the superblock version
2600	 * has not been updated to support only new format inodes, then
2601	 * convert back to the old inode format.  If the superblock version
2602	 * has been updated, then make the conversion permanent.
2603	 */
2604	ASSERT(ip->i_d.di_version == 1 || xfs_sb_version_hasnlink(&mp->m_sb));
2605	if (ip->i_d.di_version == 1) {
2606		if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
2607			/*
2608			 * Convert it back.
2609			 */
2610			ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
2611			dip->di_onlink = cpu_to_be16(ip->i_d.di_nlink);
2612		} else {
2613			/*
2614			 * The superblock version has already been bumped,
2615			 * so just make the conversion to the new inode
2616			 * format permanent.
2617			 */
2618			ip->i_d.di_version = 2;
2619			dip->di_version = 2;
2620			ip->i_d.di_onlink = 0;
2621			dip->di_onlink = 0;
2622			memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
2623			memset(&(dip->di_pad[0]), 0,
2624			      sizeof(dip->di_pad));
2625			ASSERT(xfs_get_projid(ip) == 0);
2626		}
2627	}
2628
2629	xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK, bp);
2630	if (XFS_IFORK_Q(ip))
2631		xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK, bp);
2632	xfs_inobp_check(mp, bp);
2633
2634	/*
2635	 * We've recorded everything logged in the inode, so we'd like to clear
2636	 * the ili_fields bits so we don't log and flush things unnecessarily.
2637	 * However, we can't stop logging all this information until the data
2638	 * we've copied into the disk buffer is written to disk.  If we did we
2639	 * might overwrite the copy of the inode in the log with all the data
2640	 * after re-logging only part of it, and in the face of a crash we
2641	 * wouldn't have all the data we need to recover.
2642	 *
2643	 * What we do is move the bits to the ili_last_fields field.  When
2644	 * logging the inode, these bits are moved back to the ili_fields field.
2645	 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
2646	 * know that the information those bits represent is permanently on
2647	 * disk.  As long as the flush completes before the inode is logged
2648	 * again, then both ili_fields and ili_last_fields will be cleared.
2649	 *
2650	 * We can play with the ili_fields bits here, because the inode lock
2651	 * must be held exclusively in order to set bits there and the flush
2652	 * lock protects the ili_last_fields bits.  Set ili_logged so the flush
2653	 * done routine can tell whether or not to look in the AIL.  Also, store
2654	 * the current LSN of the inode so that we can tell whether the item has
2655	 * moved in the AIL from xfs_iflush_done().  In order to read the lsn we
2656	 * need the AIL lock, because it is a 64 bit value that cannot be read
2657	 * atomically.
2658	 */
2659	if (iip != NULL && iip->ili_fields != 0) {
2660		iip->ili_last_fields = iip->ili_fields;
2661		iip->ili_fields = 0;
2662		iip->ili_logged = 1;
2663
2664		xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2665					&iip->ili_item.li_lsn);
2666
2667		/*
2668		 * Attach the function xfs_iflush_done to the inode's
2669		 * buffer.  This will remove the inode from the AIL
2670		 * and unlock the inode's flush lock when the inode is
2671		 * completely written to disk.
2672		 */
2673		xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
2674
2675		ASSERT(bp->b_fspriv != NULL);
2676		ASSERT(bp->b_iodone != NULL);
2677	} else {
2678		/*
2679		 * We're flushing an inode which is not in the AIL and has
2680		 * not been logged.  For this case we can immediately drop
2681		 * the inode flush lock because we can avoid the whole
2682		 * AIL state thing.  It's OK to drop the flush lock now,
2683		 * because we've already locked the buffer and to do anything
2684		 * you really need both.
2685		 */
2686		if (iip != NULL) {
2687			ASSERT(iip->ili_logged == 0);
2688			ASSERT(iip->ili_last_fields == 0);
2689			ASSERT((iip->ili_item.li_flags & XFS_LI_IN_AIL) == 0);
2690		}
2691		xfs_ifunlock(ip);
2692	}
2693
 
 
2694	return 0;
2695
2696corrupt_out:
2697	return XFS_ERROR(EFSCORRUPTED);
2698}
2699
2700/*
2701 * Return a pointer to the extent record at file index idx.
2702 */
2703xfs_bmbt_rec_host_t *
2704xfs_iext_get_ext(
2705	xfs_ifork_t	*ifp,		/* inode fork pointer */
2706	xfs_extnum_t	idx)		/* index of target extent */
2707{
2708	ASSERT(idx >= 0);
2709	ASSERT(idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t));
2710
2711	if ((ifp->if_flags & XFS_IFEXTIREC) && (idx == 0)) {
2712		return ifp->if_u1.if_ext_irec->er_extbuf;
2713	} else if (ifp->if_flags & XFS_IFEXTIREC) {
2714		xfs_ext_irec_t	*erp;		/* irec pointer */
2715		int		erp_idx = 0;	/* irec index */
2716		xfs_extnum_t	page_idx = idx;	/* ext index in target list */
2717
2718		erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 0);
2719		return &erp->er_extbuf[page_idx];
2720	} else if (ifp->if_bytes) {
2721		return &ifp->if_u1.if_extents[idx];
2722	} else {
2723		return NULL;
2724	}
2725}
2726
2727/*
2728 * Insert new item(s) into the extent records for incore inode
2729 * fork 'ifp'.  'count' new items are inserted at index 'idx'.
2730 */
2731void
2732xfs_iext_insert(
2733	xfs_inode_t	*ip,		/* incore inode pointer */
2734	xfs_extnum_t	idx,		/* starting index of new items */
2735	xfs_extnum_t	count,		/* number of inserted items */
2736	xfs_bmbt_irec_t	*new,		/* items to insert */
2737	int		state)		/* type of extent conversion */
2738{
2739	xfs_ifork_t	*ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df;
2740	xfs_extnum_t	i;		/* extent record index */
2741
2742	trace_xfs_iext_insert(ip, idx, new, state, _RET_IP_);
2743
2744	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
2745	xfs_iext_add(ifp, idx, count);
2746	for (i = idx; i < idx + count; i++, new++)
2747		xfs_bmbt_set_all(xfs_iext_get_ext(ifp, i), new);
2748}
2749
2750/*
2751 * This is called when the amount of space required for incore file
2752 * extents needs to be increased. The ext_diff parameter stores the
2753 * number of new extents being added and the idx parameter contains
2754 * the extent index where the new extents will be added. If the new
2755 * extents are being appended, then we just need to (re)allocate and
2756 * initialize the space. Otherwise, if the new extents are being
2757 * inserted into the middle of the existing entries, a bit more work
2758 * is required to make room for the new extents to be inserted. The
2759 * caller is responsible for filling in the new extent entries upon
2760 * return.
2761 */
2762void
2763xfs_iext_add(
2764	xfs_ifork_t	*ifp,		/* inode fork pointer */
2765	xfs_extnum_t	idx,		/* index to begin adding exts */
2766	int		ext_diff)	/* number of extents to add */
2767{
2768	int		byte_diff;	/* new bytes being added */
2769	int		new_size;	/* size of extents after adding */
2770	xfs_extnum_t	nextents;	/* number of extents in file */
2771
2772	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
2773	ASSERT((idx >= 0) && (idx <= nextents));
2774	byte_diff = ext_diff * sizeof(xfs_bmbt_rec_t);
2775	new_size = ifp->if_bytes + byte_diff;
2776	/*
2777	 * If the new number of extents (nextents + ext_diff)
2778	 * fits inside the inode, then continue to use the inline
2779	 * extent buffer.
2780	 */
2781	if (nextents + ext_diff <= XFS_INLINE_EXTS) {
2782		if (idx < nextents) {
2783			memmove(&ifp->if_u2.if_inline_ext[idx + ext_diff],
2784				&ifp->if_u2.if_inline_ext[idx],
2785				(nextents - idx) * sizeof(xfs_bmbt_rec_t));
2786			memset(&ifp->if_u2.if_inline_ext[idx], 0, byte_diff);
2787		}
2788		ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
2789		ifp->if_real_bytes = 0;
2790	}
2791	/*
2792	 * Otherwise use a linear (direct) extent list.
2793	 * If the extents are currently inside the inode,
2794	 * xfs_iext_realloc_direct will switch us from
2795	 * inline to direct extent allocation mode.
2796	 */
2797	else if (nextents + ext_diff <= XFS_LINEAR_EXTS) {
2798		xfs_iext_realloc_direct(ifp, new_size);
2799		if (idx < nextents) {
2800			memmove(&ifp->if_u1.if_extents[idx + ext_diff],
2801				&ifp->if_u1.if_extents[idx],
2802				(nextents - idx) * sizeof(xfs_bmbt_rec_t));
2803			memset(&ifp->if_u1.if_extents[idx], 0, byte_diff);
2804		}
2805	}
2806	/* Indirection array */
2807	else {
2808		xfs_ext_irec_t	*erp;
2809		int		erp_idx = 0;
2810		int		page_idx = idx;
2811
2812		ASSERT(nextents + ext_diff > XFS_LINEAR_EXTS);
2813		if (ifp->if_flags & XFS_IFEXTIREC) {
2814			erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 1);
2815		} else {
2816			xfs_iext_irec_init(ifp);
2817			ASSERT(ifp->if_flags & XFS_IFEXTIREC);
2818			erp = ifp->if_u1.if_ext_irec;
2819		}
2820		/* Extents fit in target extent page */
2821		if (erp && erp->er_extcount + ext_diff <= XFS_LINEAR_EXTS) {
2822			if (page_idx < erp->er_extcount) {
2823				memmove(&erp->er_extbuf[page_idx + ext_diff],
2824					&erp->er_extbuf[page_idx],
2825					(erp->er_extcount - page_idx) *
2826					sizeof(xfs_bmbt_rec_t));
2827				memset(&erp->er_extbuf[page_idx], 0, byte_diff);
2828			}
2829			erp->er_extcount += ext_diff;
2830			xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
2831		}
2832		/* Insert a new extent page */
2833		else if (erp) {
2834			xfs_iext_add_indirect_multi(ifp,
2835				erp_idx, page_idx, ext_diff);
2836		}
2837		/*
2838		 * If extent(s) are being appended to the last page in
2839		 * the indirection array and the new extent(s) don't fit
2840		 * in the page, then erp is NULL and erp_idx is set to
2841		 * the next index needed in the indirection array.
2842		 */
2843		else {
2844			int	count = ext_diff;
2845
2846			while (count) {
2847				erp = xfs_iext_irec_new(ifp, erp_idx);
2848				erp->er_extcount = count;
2849				count -= MIN(count, (int)XFS_LINEAR_EXTS);
2850				if (count) {
2851					erp_idx++;
2852				}
2853			}
2854		}
2855	}
2856	ifp->if_bytes = new_size;
2857}
2858
2859/*
2860 * This is called when incore extents are being added to the indirection
2861 * array and the new extents do not fit in the target extent list. The
2862 * erp_idx parameter contains the irec index for the target extent list
2863 * in the indirection array, and the idx parameter contains the extent
2864 * index within the list. The number of extents being added is stored
2865 * in the count parameter.
2866 *
2867 *    |-------|   |-------|
2868 *    |       |   |       |    idx - number of extents before idx
2869 *    |  idx  |   | count |
2870 *    |       |   |       |    count - number of extents being inserted at idx
2871 *    |-------|   |-------|
2872 *    | count |   | nex2  |    nex2 - number of extents after idx + count
2873 *    |-------|   |-------|
2874 */
2875void
2876xfs_iext_add_indirect_multi(
2877	xfs_ifork_t	*ifp,			/* inode fork pointer */
2878	int		erp_idx,		/* target extent irec index */
2879	xfs_extnum_t	idx,			/* index within target list */
2880	int		count)			/* new extents being added */
2881{
2882	int		byte_diff;		/* new bytes being added */
2883	xfs_ext_irec_t	*erp;			/* pointer to irec entry */
2884	xfs_extnum_t	ext_diff;		/* number of extents to add */
2885	xfs_extnum_t	ext_cnt;		/* new extents still needed */
2886	xfs_extnum_t	nex2;			/* extents after idx + count */
2887	xfs_bmbt_rec_t	*nex2_ep = NULL;	/* temp list for nex2 extents */
2888	int		nlists;			/* number of irec's (lists) */
2889
2890	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
2891	erp = &ifp->if_u1.if_ext_irec[erp_idx];
2892	nex2 = erp->er_extcount - idx;
2893	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
2894
2895	/*
2896	 * Save second part of target extent list
2897	 * (all extents past */
2898	if (nex2) {
2899		byte_diff = nex2 * sizeof(xfs_bmbt_rec_t);
2900		nex2_ep = (xfs_bmbt_rec_t *) kmem_alloc(byte_diff, KM_NOFS);
2901		memmove(nex2_ep, &erp->er_extbuf[idx], byte_diff);
2902		erp->er_extcount -= nex2;
2903		xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -nex2);
2904		memset(&erp->er_extbuf[idx], 0, byte_diff);
2905	}
2906
2907	/*
2908	 * Add the new extents to the end of the target
2909	 * list, then allocate new irec record(s) and
2910	 * extent buffer(s) as needed to store the rest
2911	 * of the new extents.
2912	 */
2913	ext_cnt = count;
2914	ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS - erp->er_extcount);
2915	if (ext_diff) {
2916		erp->er_extcount += ext_diff;
2917		xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
2918		ext_cnt -= ext_diff;
2919	}
2920	while (ext_cnt) {
2921		erp_idx++;
2922		erp = xfs_iext_irec_new(ifp, erp_idx);
2923		ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS);
2924		erp->er_extcount = ext_diff;
2925		xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
2926		ext_cnt -= ext_diff;
2927	}
2928
2929	/* Add nex2 extents back to indirection array */
2930	if (nex2) {
2931		xfs_extnum_t	ext_avail;
2932		int		i;
2933
2934		byte_diff = nex2 * sizeof(xfs_bmbt_rec_t);
2935		ext_avail = XFS_LINEAR_EXTS - erp->er_extcount;
2936		i = 0;
2937		/*
2938		 * If nex2 extents fit in the current page, append
2939		 * nex2_ep after the new extents.
2940		 */
2941		if (nex2 <= ext_avail) {
2942			i = erp->er_extcount;
2943		}
2944		/*
2945		 * Otherwise, check if space is available in the
2946		 * next page.
2947		 */
2948		else if ((erp_idx < nlists - 1) &&
2949			 (nex2 <= (ext_avail = XFS_LINEAR_EXTS -
2950			  ifp->if_u1.if_ext_irec[erp_idx+1].er_extcount))) {
2951			erp_idx++;
2952			erp++;
2953			/* Create a hole for nex2 extents */
2954			memmove(&erp->er_extbuf[nex2], erp->er_extbuf,
2955				erp->er_extcount * sizeof(xfs_bmbt_rec_t));
2956		}
2957		/*
2958		 * Final choice, create a new extent page for
2959		 * nex2 extents.
2960		 */
2961		else {
2962			erp_idx++;
2963			erp = xfs_iext_irec_new(ifp, erp_idx);
2964		}
2965		memmove(&erp->er_extbuf[i], nex2_ep, byte_diff);
2966		kmem_free(nex2_ep);
2967		erp->er_extcount += nex2;
2968		xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, nex2);
2969	}
2970}
2971
2972/*
2973 * This is called when the amount of space required for incore file
2974 * extents needs to be decreased. The ext_diff parameter stores the
2975 * number of extents to be removed and the idx parameter contains
2976 * the extent index where the extents will be removed from.
2977 *
2978 * If the amount of space needed has decreased below the linear
2979 * limit, XFS_IEXT_BUFSZ, then switch to using the contiguous
2980 * extent array.  Otherwise, use kmem_realloc() to adjust the
2981 * size to what is needed.
2982 */
2983void
2984xfs_iext_remove(
2985	xfs_inode_t	*ip,		/* incore inode pointer */
2986	xfs_extnum_t	idx,		/* index to begin removing exts */
2987	int		ext_diff,	/* number of extents to remove */
2988	int		state)		/* type of extent conversion */
2989{
2990	xfs_ifork_t	*ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df;
2991	xfs_extnum_t	nextents;	/* number of extents in file */
2992	int		new_size;	/* size of extents after removal */
2993
2994	trace_xfs_iext_remove(ip, idx, state, _RET_IP_);
2995
2996	ASSERT(ext_diff > 0);
2997	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
2998	new_size = (nextents - ext_diff) * sizeof(xfs_bmbt_rec_t);
2999
3000	if (new_size == 0) {
3001		xfs_iext_destroy(ifp);
3002	} else if (ifp->if_flags & XFS_IFEXTIREC) {
3003		xfs_iext_remove_indirect(ifp, idx, ext_diff);
3004	} else if (ifp->if_real_bytes) {
3005		xfs_iext_remove_direct(ifp, idx, ext_diff);
3006	} else {
3007		xfs_iext_remove_inline(ifp, idx, ext_diff);
3008	}
3009	ifp->if_bytes = new_size;
3010}
3011
3012/*
3013 * This removes ext_diff extents from the inline buffer, beginning
3014 * at extent index idx.
3015 */
3016void
3017xfs_iext_remove_inline(
3018	xfs_ifork_t	*ifp,		/* inode fork pointer */
3019	xfs_extnum_t	idx,		/* index to begin removing exts */
3020	int		ext_diff)	/* number of extents to remove */
3021{
3022	int		nextents;	/* number of extents in file */
3023
3024	ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
3025	ASSERT(idx < XFS_INLINE_EXTS);
3026	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
3027	ASSERT(((nextents - ext_diff) > 0) &&
3028		(nextents - ext_diff) < XFS_INLINE_EXTS);
3029
3030	if (idx + ext_diff < nextents) {
3031		memmove(&ifp->if_u2.if_inline_ext[idx],
3032			&ifp->if_u2.if_inline_ext[idx + ext_diff],
3033			(nextents - (idx + ext_diff)) *
3034			 sizeof(xfs_bmbt_rec_t));
3035		memset(&ifp->if_u2.if_inline_ext[nextents - ext_diff],
3036			0, ext_diff * sizeof(xfs_bmbt_rec_t));
3037	} else {
3038		memset(&ifp->if_u2.if_inline_ext[idx], 0,
3039			ext_diff * sizeof(xfs_bmbt_rec_t));
3040	}
3041}
3042
3043/*
3044 * This removes ext_diff extents from a linear (direct) extent list,
3045 * beginning at extent index idx. If the extents are being removed
3046 * from the end of the list (ie. truncate) then we just need to re-
3047 * allocate the list to remove the extra space. Otherwise, if the
3048 * extents are being removed from the middle of the existing extent
3049 * entries, then we first need to move the extent records beginning
3050 * at idx + ext_diff up in the list to overwrite the records being
3051 * removed, then remove the extra space via kmem_realloc.
3052 */
3053void
3054xfs_iext_remove_direct(
3055	xfs_ifork_t	*ifp,		/* inode fork pointer */
3056	xfs_extnum_t	idx,		/* index to begin removing exts */
3057	int		ext_diff)	/* number of extents to remove */
3058{
3059	xfs_extnum_t	nextents;	/* number of extents in file */
3060	int		new_size;	/* size of extents after removal */
3061
3062	ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
3063	new_size = ifp->if_bytes -
3064		(ext_diff * sizeof(xfs_bmbt_rec_t));
3065	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
3066
3067	if (new_size == 0) {
3068		xfs_iext_destroy(ifp);
3069		return;
3070	}
3071	/* Move extents up in the list (if needed) */
3072	if (idx + ext_diff < nextents) {
3073		memmove(&ifp->if_u1.if_extents[idx],
3074			&ifp->if_u1.if_extents[idx + ext_diff],
3075			(nextents - (idx + ext_diff)) *
3076			 sizeof(xfs_bmbt_rec_t));
3077	}
3078	memset(&ifp->if_u1.if_extents[nextents - ext_diff],
3079		0, ext_diff * sizeof(xfs_bmbt_rec_t));
3080	/*
3081	 * Reallocate the direct extent list. If the extents
3082	 * will fit inside the inode then xfs_iext_realloc_direct
3083	 * will switch from direct to inline extent allocation
3084	 * mode for us.
3085	 */
3086	xfs_iext_realloc_direct(ifp, new_size);
3087	ifp->if_bytes = new_size;
3088}
3089
3090/*
3091 * This is called when incore extents are being removed from the
3092 * indirection array and the extents being removed span multiple extent
3093 * buffers. The idx parameter contains the file extent index where we
3094 * want to begin removing extents, and the count parameter contains
3095 * how many extents need to be removed.
3096 *
3097 *    |-------|   |-------|
3098 *    | nex1  |   |       |    nex1 - number of extents before idx
3099 *    |-------|   | count |
3100 *    |       |   |       |    count - number of extents being removed at idx
3101 *    | count |   |-------|
3102 *    |       |   | nex2  |    nex2 - number of extents after idx + count
3103 *    |-------|   |-------|
3104 */
3105void
3106xfs_iext_remove_indirect(
3107	xfs_ifork_t	*ifp,		/* inode fork pointer */
3108	xfs_extnum_t	idx,		/* index to begin removing extents */
3109	int		count)		/* number of extents to remove */
3110{
3111	xfs_ext_irec_t	*erp;		/* indirection array pointer */
3112	int		erp_idx = 0;	/* indirection array index */
3113	xfs_extnum_t	ext_cnt;	/* extents left to remove */
3114	xfs_extnum_t	ext_diff;	/* extents to remove in current list */
3115	xfs_extnum_t	nex1;		/* number of extents before idx */
3116	xfs_extnum_t	nex2;		/* extents after idx + count */
3117	int		page_idx = idx;	/* index in target extent list */
3118
3119	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3120	erp = xfs_iext_idx_to_irec(ifp,  &page_idx, &erp_idx, 0);
3121	ASSERT(erp != NULL);
3122	nex1 = page_idx;
3123	ext_cnt = count;
3124	while (ext_cnt) {
3125		nex2 = MAX((erp->er_extcount - (nex1 + ext_cnt)), 0);
3126		ext_diff = MIN(ext_cnt, (erp->er_extcount - nex1));
3127		/*
3128		 * Check for deletion of entire list;
3129		 * xfs_iext_irec_remove() updates extent offsets.
3130		 */
3131		if (ext_diff == erp->er_extcount) {
3132			xfs_iext_irec_remove(ifp, erp_idx);
3133			ext_cnt -= ext_diff;
3134			nex1 = 0;
3135			if (ext_cnt) {
3136				ASSERT(erp_idx < ifp->if_real_bytes /
3137					XFS_IEXT_BUFSZ);
3138				erp = &ifp->if_u1.if_ext_irec[erp_idx];
3139				nex1 = 0;
3140				continue;
3141			} else {
3142				break;
3143			}
3144		}
3145		/* Move extents up (if needed) */
3146		if (nex2) {
3147			memmove(&erp->er_extbuf[nex1],
3148				&erp->er_extbuf[nex1 + ext_diff],
3149				nex2 * sizeof(xfs_bmbt_rec_t));
3150		}
3151		/* Zero out rest of page */
3152		memset(&erp->er_extbuf[nex1 + nex2], 0, (XFS_IEXT_BUFSZ -
3153			((nex1 + nex2) * sizeof(xfs_bmbt_rec_t))));
3154		/* Update remaining counters */
3155		erp->er_extcount -= ext_diff;
3156		xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -ext_diff);
3157		ext_cnt -= ext_diff;
3158		nex1 = 0;
3159		erp_idx++;
3160		erp++;
3161	}
3162	ifp->if_bytes -= count * sizeof(xfs_bmbt_rec_t);
3163	xfs_iext_irec_compact(ifp);
3164}
3165
3166/*
3167 * Create, destroy, or resize a linear (direct) block of extents.
3168 */
3169void
3170xfs_iext_realloc_direct(
3171	xfs_ifork_t	*ifp,		/* inode fork pointer */
3172	int		new_size)	/* new size of extents */
3173{
3174	int		rnew_size;	/* real new size of extents */
3175
3176	rnew_size = new_size;
3177
3178	ASSERT(!(ifp->if_flags & XFS_IFEXTIREC) ||
3179		((new_size >= 0) && (new_size <= XFS_IEXT_BUFSZ) &&
3180		 (new_size != ifp->if_real_bytes)));
3181
3182	/* Free extent records */
3183	if (new_size == 0) {
3184		xfs_iext_destroy(ifp);
3185	}
3186	/* Resize direct extent list and zero any new bytes */
3187	else if (ifp->if_real_bytes) {
3188		/* Check if extents will fit inside the inode */
3189		if (new_size <= XFS_INLINE_EXTS * sizeof(xfs_bmbt_rec_t)) {
3190			xfs_iext_direct_to_inline(ifp, new_size /
3191				(uint)sizeof(xfs_bmbt_rec_t));
3192			ifp->if_bytes = new_size;
3193			return;
3194		}
3195		if (!is_power_of_2(new_size)){
3196			rnew_size = roundup_pow_of_two(new_size);
3197		}
3198		if (rnew_size != ifp->if_real_bytes) {
3199			ifp->if_u1.if_extents =
3200				kmem_realloc(ifp->if_u1.if_extents,
3201						rnew_size,
3202						ifp->if_real_bytes, KM_NOFS);
3203		}
3204		if (rnew_size > ifp->if_real_bytes) {
3205			memset(&ifp->if_u1.if_extents[ifp->if_bytes /
3206				(uint)sizeof(xfs_bmbt_rec_t)], 0,
3207				rnew_size - ifp->if_real_bytes);
3208		}
3209	}
3210	/*
3211	 * Switch from the inline extent buffer to a direct
3212	 * extent list. Be sure to include the inline extent
3213	 * bytes in new_size.
3214	 */
3215	else {
3216		new_size += ifp->if_bytes;
3217		if (!is_power_of_2(new_size)) {
3218			rnew_size = roundup_pow_of_two(new_size);
3219		}
3220		xfs_iext_inline_to_direct(ifp, rnew_size);
3221	}
3222	ifp->if_real_bytes = rnew_size;
3223	ifp->if_bytes = new_size;
3224}
3225
3226/*
3227 * Switch from linear (direct) extent records to inline buffer.
3228 */
3229void
3230xfs_iext_direct_to_inline(
3231	xfs_ifork_t	*ifp,		/* inode fork pointer */
3232	xfs_extnum_t	nextents)	/* number of extents in file */
3233{
3234	ASSERT(ifp->if_flags & XFS_IFEXTENTS);
3235	ASSERT(nextents <= XFS_INLINE_EXTS);
3236	/*
3237	 * The inline buffer was zeroed when we switched
3238	 * from inline to direct extent allocation mode,
3239	 * so we don't need to clear it here.
3240	 */
3241	memcpy(ifp->if_u2.if_inline_ext, ifp->if_u1.if_extents,
3242		nextents * sizeof(xfs_bmbt_rec_t));
3243	kmem_free(ifp->if_u1.if_extents);
3244	ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
3245	ifp->if_real_bytes = 0;
3246}
3247
3248/*
3249 * Switch from inline buffer to linear (direct) extent records.
3250 * new_size should already be rounded up to the next power of 2
3251 * by the caller (when appropriate), so use new_size as it is.
3252 * However, since new_size may be rounded up, we can't update
3253 * if_bytes here. It is the caller's responsibility to update
3254 * if_bytes upon return.
3255 */
3256void
3257xfs_iext_inline_to_direct(
3258	xfs_ifork_t	*ifp,		/* inode fork pointer */
3259	int		new_size)	/* number of extents in file */
3260{
3261	ifp->if_u1.if_extents = kmem_alloc(new_size, KM_NOFS);
3262	memset(ifp->if_u1.if_extents, 0, new_size);
3263	if (ifp->if_bytes) {
3264		memcpy(ifp->if_u1.if_extents, ifp->if_u2.if_inline_ext,
3265			ifp->if_bytes);
3266		memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS *
3267			sizeof(xfs_bmbt_rec_t));
3268	}
3269	ifp->if_real_bytes = new_size;
3270}
3271
3272/*
3273 * Resize an extent indirection array to new_size bytes.
3274 */
3275STATIC void
3276xfs_iext_realloc_indirect(
3277	xfs_ifork_t	*ifp,		/* inode fork pointer */
3278	int		new_size)	/* new indirection array size */
3279{
3280	int		nlists;		/* number of irec's (ex lists) */
3281	int		size;		/* current indirection array size */
3282
3283	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3284	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3285	size = nlists * sizeof(xfs_ext_irec_t);
3286	ASSERT(ifp->if_real_bytes);
3287	ASSERT((new_size >= 0) && (new_size != size));
3288	if (new_size == 0) {
3289		xfs_iext_destroy(ifp);
3290	} else {
3291		ifp->if_u1.if_ext_irec = (xfs_ext_irec_t *)
3292			kmem_realloc(ifp->if_u1.if_ext_irec,
3293				new_size, size, KM_NOFS);
3294	}
3295}
3296
3297/*
3298 * Switch from indirection array to linear (direct) extent allocations.
3299 */
3300STATIC void
3301xfs_iext_indirect_to_direct(
3302	 xfs_ifork_t	*ifp)		/* inode fork pointer */
3303{
3304	xfs_bmbt_rec_host_t *ep;	/* extent record pointer */
3305	xfs_extnum_t	nextents;	/* number of extents in file */
3306	int		size;		/* size of file extents */
3307
3308	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3309	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
3310	ASSERT(nextents <= XFS_LINEAR_EXTS);
3311	size = nextents * sizeof(xfs_bmbt_rec_t);
3312
3313	xfs_iext_irec_compact_pages(ifp);
3314	ASSERT(ifp->if_real_bytes == XFS_IEXT_BUFSZ);
3315
3316	ep = ifp->if_u1.if_ext_irec->er_extbuf;
3317	kmem_free(ifp->if_u1.if_ext_irec);
3318	ifp->if_flags &= ~XFS_IFEXTIREC;
3319	ifp->if_u1.if_extents = ep;
3320	ifp->if_bytes = size;
3321	if (nextents < XFS_LINEAR_EXTS) {
3322		xfs_iext_realloc_direct(ifp, size);
3323	}
3324}
3325
3326/*
3327 * Free incore file extents.
3328 */
3329void
3330xfs_iext_destroy(
3331	xfs_ifork_t	*ifp)		/* inode fork pointer */
3332{
3333	if (ifp->if_flags & XFS_IFEXTIREC) {
3334		int	erp_idx;
3335		int	nlists;
3336
3337		nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3338		for (erp_idx = nlists - 1; erp_idx >= 0 ; erp_idx--) {
3339			xfs_iext_irec_remove(ifp, erp_idx);
3340		}
3341		ifp->if_flags &= ~XFS_IFEXTIREC;
3342	} else if (ifp->if_real_bytes) {
3343		kmem_free(ifp->if_u1.if_extents);
3344	} else if (ifp->if_bytes) {
3345		memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS *
3346			sizeof(xfs_bmbt_rec_t));
3347	}
3348	ifp->if_u1.if_extents = NULL;
3349	ifp->if_real_bytes = 0;
3350	ifp->if_bytes = 0;
3351}
3352
3353/*
3354 * Return a pointer to the extent record for file system block bno.
3355 */
3356xfs_bmbt_rec_host_t *			/* pointer to found extent record */
3357xfs_iext_bno_to_ext(
3358	xfs_ifork_t	*ifp,		/* inode fork pointer */
3359	xfs_fileoff_t	bno,		/* block number to search for */
3360	xfs_extnum_t	*idxp)		/* index of target extent */
3361{
3362	xfs_bmbt_rec_host_t *base;	/* pointer to first extent */
3363	xfs_filblks_t	blockcount = 0;	/* number of blocks in extent */
3364	xfs_bmbt_rec_host_t *ep = NULL;	/* pointer to target extent */
3365	xfs_ext_irec_t	*erp = NULL;	/* indirection array pointer */
3366	int		high;		/* upper boundary in search */
3367	xfs_extnum_t	idx = 0;	/* index of target extent */
3368	int		low;		/* lower boundary in search */
3369	xfs_extnum_t	nextents;	/* number of file extents */
3370	xfs_fileoff_t	startoff = 0;	/* start offset of extent */
3371
3372	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
3373	if (nextents == 0) {
3374		*idxp = 0;
3375		return NULL;
3376	}
3377	low = 0;
3378	if (ifp->if_flags & XFS_IFEXTIREC) {
3379		/* Find target extent list */
3380		int	erp_idx = 0;
3381		erp = xfs_iext_bno_to_irec(ifp, bno, &erp_idx);
3382		base = erp->er_extbuf;
3383		high = erp->er_extcount - 1;
3384	} else {
3385		base = ifp->if_u1.if_extents;
3386		high = nextents - 1;
3387	}
3388	/* Binary search extent records */
3389	while (low <= high) {
3390		idx = (low + high) >> 1;
3391		ep = base + idx;
3392		startoff = xfs_bmbt_get_startoff(ep);
3393		blockcount = xfs_bmbt_get_blockcount(ep);
3394		if (bno < startoff) {
3395			high = idx - 1;
3396		} else if (bno >= startoff + blockcount) {
3397			low = idx + 1;
3398		} else {
3399			/* Convert back to file-based extent index */
3400			if (ifp->if_flags & XFS_IFEXTIREC) {
3401				idx += erp->er_extoff;
3402			}
3403			*idxp = idx;
3404			return ep;
3405		}
3406	}
3407	/* Convert back to file-based extent index */
3408	if (ifp->if_flags & XFS_IFEXTIREC) {
3409		idx += erp->er_extoff;
3410	}
3411	if (bno >= startoff + blockcount) {
3412		if (++idx == nextents) {
3413			ep = NULL;
3414		} else {
3415			ep = xfs_iext_get_ext(ifp, idx);
3416		}
3417	}
3418	*idxp = idx;
3419	return ep;
3420}
3421
3422/*
3423 * Return a pointer to the indirection array entry containing the
3424 * extent record for filesystem block bno. Store the index of the
3425 * target irec in *erp_idxp.
3426 */
3427xfs_ext_irec_t *			/* pointer to found extent record */
3428xfs_iext_bno_to_irec(
3429	xfs_ifork_t	*ifp,		/* inode fork pointer */
3430	xfs_fileoff_t	bno,		/* block number to search for */
3431	int		*erp_idxp)	/* irec index of target ext list */
3432{
3433	xfs_ext_irec_t	*erp = NULL;	/* indirection array pointer */
3434	xfs_ext_irec_t	*erp_next;	/* next indirection array entry */
3435	int		erp_idx;	/* indirection array index */
3436	int		nlists;		/* number of extent irec's (lists) */
3437	int		high;		/* binary search upper limit */
3438	int		low;		/* binary search lower limit */
3439
3440	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3441	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3442	erp_idx = 0;
3443	low = 0;
3444	high = nlists - 1;
3445	while (low <= high) {
3446		erp_idx = (low + high) >> 1;
3447		erp = &ifp->if_u1.if_ext_irec[erp_idx];
3448		erp_next = erp_idx < nlists - 1 ? erp + 1 : NULL;
3449		if (bno < xfs_bmbt_get_startoff(erp->er_extbuf)) {
3450			high = erp_idx - 1;
3451		} else if (erp_next && bno >=
3452			   xfs_bmbt_get_startoff(erp_next->er_extbuf)) {
3453			low = erp_idx + 1;
3454		} else {
3455			break;
3456		}
3457	}
3458	*erp_idxp = erp_idx;
3459	return erp;
3460}
3461
3462/*
3463 * Return a pointer to the indirection array entry containing the
3464 * extent record at file extent index *idxp. Store the index of the
3465 * target irec in *erp_idxp and store the page index of the target
3466 * extent record in *idxp.
3467 */
3468xfs_ext_irec_t *
3469xfs_iext_idx_to_irec(
3470	xfs_ifork_t	*ifp,		/* inode fork pointer */
3471	xfs_extnum_t	*idxp,		/* extent index (file -> page) */
3472	int		*erp_idxp,	/* pointer to target irec */
3473	int		realloc)	/* new bytes were just added */
3474{
3475	xfs_ext_irec_t	*prev;		/* pointer to previous irec */
3476	xfs_ext_irec_t	*erp = NULL;	/* pointer to current irec */
3477	int		erp_idx;	/* indirection array index */
3478	int		nlists;		/* number of irec's (ex lists) */
3479	int		high;		/* binary search upper limit */
3480	int		low;		/* binary search lower limit */
3481	xfs_extnum_t	page_idx = *idxp; /* extent index in target list */
3482
3483	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3484	ASSERT(page_idx >= 0);
3485	ASSERT(page_idx <= ifp->if_bytes / sizeof(xfs_bmbt_rec_t));
3486	ASSERT(page_idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t) || realloc);
3487
3488	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3489	erp_idx = 0;
3490	low = 0;
3491	high = nlists - 1;
3492
3493	/* Binary search extent irec's */
3494	while (low <= high) {
3495		erp_idx = (low + high) >> 1;
3496		erp = &ifp->if_u1.if_ext_irec[erp_idx];
3497		prev = erp_idx > 0 ? erp - 1 : NULL;
3498		if (page_idx < erp->er_extoff || (page_idx == erp->er_extoff &&
3499		     realloc && prev && prev->er_extcount < XFS_LINEAR_EXTS)) {
3500			high = erp_idx - 1;
3501		} else if (page_idx > erp->er_extoff + erp->er_extcount ||
3502			   (page_idx == erp->er_extoff + erp->er_extcount &&
3503			    !realloc)) {
3504			low = erp_idx + 1;
3505		} else if (page_idx == erp->er_extoff + erp->er_extcount &&
3506			   erp->er_extcount == XFS_LINEAR_EXTS) {
3507			ASSERT(realloc);
3508			page_idx = 0;
3509			erp_idx++;
3510			erp = erp_idx < nlists ? erp + 1 : NULL;
3511			break;
3512		} else {
3513			page_idx -= erp->er_extoff;
3514			break;
3515		}
3516	}
3517	*idxp = page_idx;
3518	*erp_idxp = erp_idx;
3519	return(erp);
3520}
3521
3522/*
3523 * Allocate and initialize an indirection array once the space needed
3524 * for incore extents increases above XFS_IEXT_BUFSZ.
3525 */
3526void
3527xfs_iext_irec_init(
3528	xfs_ifork_t	*ifp)		/* inode fork pointer */
3529{
3530	xfs_ext_irec_t	*erp;		/* indirection array pointer */
3531	xfs_extnum_t	nextents;	/* number of extents in file */
3532
3533	ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
3534	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
3535	ASSERT(nextents <= XFS_LINEAR_EXTS);
3536
3537	erp = kmem_alloc(sizeof(xfs_ext_irec_t), KM_NOFS);
3538
3539	if (nextents == 0) {
3540		ifp->if_u1.if_extents = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS);
3541	} else if (!ifp->if_real_bytes) {
3542		xfs_iext_inline_to_direct(ifp, XFS_IEXT_BUFSZ);
3543	} else if (ifp->if_real_bytes < XFS_IEXT_BUFSZ) {
3544		xfs_iext_realloc_direct(ifp, XFS_IEXT_BUFSZ);
3545	}
3546	erp->er_extbuf = ifp->if_u1.if_extents;
3547	erp->er_extcount = nextents;
3548	erp->er_extoff = 0;
3549
3550	ifp->if_flags |= XFS_IFEXTIREC;
3551	ifp->if_real_bytes = XFS_IEXT_BUFSZ;
3552	ifp->if_bytes = nextents * sizeof(xfs_bmbt_rec_t);
3553	ifp->if_u1.if_ext_irec = erp;
3554
3555	return;
3556}
3557
3558/*
3559 * Allocate and initialize a new entry in the indirection array.
3560 */
3561xfs_ext_irec_t *
3562xfs_iext_irec_new(
3563	xfs_ifork_t	*ifp,		/* inode fork pointer */
3564	int		erp_idx)	/* index for new irec */
3565{
3566	xfs_ext_irec_t	*erp;		/* indirection array pointer */
3567	int		i;		/* loop counter */
3568	int		nlists;		/* number of irec's (ex lists) */
3569
3570	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3571	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3572
3573	/* Resize indirection array */
3574	xfs_iext_realloc_indirect(ifp, ++nlists *
3575				  sizeof(xfs_ext_irec_t));
3576	/*
3577	 * Move records down in the array so the
3578	 * new page can use erp_idx.
3579	 */
3580	erp = ifp->if_u1.if_ext_irec;
3581	for (i = nlists - 1; i > erp_idx; i--) {
3582		memmove(&erp[i], &erp[i-1], sizeof(xfs_ext_irec_t));
3583	}
3584	ASSERT(i == erp_idx);
3585
3586	/* Initialize new extent record */
3587	erp = ifp->if_u1.if_ext_irec;
3588	erp[erp_idx].er_extbuf = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS);
3589	ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ;
3590	memset(erp[erp_idx].er_extbuf, 0, XFS_IEXT_BUFSZ);
3591	erp[erp_idx].er_extcount = 0;
3592	erp[erp_idx].er_extoff = erp_idx > 0 ?
3593		erp[erp_idx-1].er_extoff + erp[erp_idx-1].er_extcount : 0;
3594	return (&erp[erp_idx]);
3595}
3596
3597/*
3598 * Remove a record from the indirection array.
3599 */
3600void
3601xfs_iext_irec_remove(
3602	xfs_ifork_t	*ifp,		/* inode fork pointer */
3603	int		erp_idx)	/* irec index to remove */
3604{
3605	xfs_ext_irec_t	*erp;		/* indirection array pointer */
3606	int		i;		/* loop counter */
3607	int		nlists;		/* number of irec's (ex lists) */
3608
3609	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3610	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3611	erp = &ifp->if_u1.if_ext_irec[erp_idx];
3612	if (erp->er_extbuf) {
3613		xfs_iext_irec_update_extoffs(ifp, erp_idx + 1,
3614			-erp->er_extcount);
3615		kmem_free(erp->er_extbuf);
3616	}
3617	/* Compact extent records */
3618	erp = ifp->if_u1.if_ext_irec;
3619	for (i = erp_idx; i < nlists - 1; i++) {
3620		memmove(&erp[i], &erp[i+1], sizeof(xfs_ext_irec_t));
3621	}
3622	/*
3623	 * Manually free the last extent record from the indirection
3624	 * array.  A call to xfs_iext_realloc_indirect() with a size
3625	 * of zero would result in a call to xfs_iext_destroy() which
3626	 * would in turn call this function again, creating a nasty
3627	 * infinite loop.
3628	 */
3629	if (--nlists) {
3630		xfs_iext_realloc_indirect(ifp,
3631			nlists * sizeof(xfs_ext_irec_t));
3632	} else {
3633		kmem_free(ifp->if_u1.if_ext_irec);
3634	}
3635	ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ;
3636}
3637
3638/*
3639 * This is called to clean up large amounts of unused memory allocated
3640 * by the indirection array.  Before compacting anything though, verify
3641 * that the indirection array is still needed and switch back to the
3642 * linear extent list (or even the inline buffer) if possible.  The
3643 * compaction policy is as follows:
3644 *
3645 *    Full Compaction: Extents fit into a single page (or inline buffer)
3646 * Partial Compaction: Extents occupy less than 50% of allocated space
3647 *      No Compaction: Extents occupy at least 50% of allocated space
3648 */
3649void
3650xfs_iext_irec_compact(
3651	xfs_ifork_t	*ifp)		/* inode fork pointer */
3652{
3653	xfs_extnum_t	nextents;	/* number of extents in file */
3654	int		nlists;		/* number of irec's (ex lists) */
3655
3656	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3657	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3658	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
3659
3660	if (nextents == 0) {
3661		xfs_iext_destroy(ifp);
3662	} else if (nextents <= XFS_INLINE_EXTS) {
3663		xfs_iext_indirect_to_direct(ifp);
3664		xfs_iext_direct_to_inline(ifp, nextents);
3665	} else if (nextents <= XFS_LINEAR_EXTS) {
3666		xfs_iext_indirect_to_direct(ifp);
3667	} else if (nextents < (nlists * XFS_LINEAR_EXTS) >> 1) {
3668		xfs_iext_irec_compact_pages(ifp);
3669	}
3670}
3671
3672/*
3673 * Combine extents from neighboring extent pages.
3674 */
3675void
3676xfs_iext_irec_compact_pages(
3677	xfs_ifork_t	*ifp)		/* inode fork pointer */
3678{
3679	xfs_ext_irec_t	*erp, *erp_next;/* pointers to irec entries */
3680	int		erp_idx = 0;	/* indirection array index */
3681	int		nlists;		/* number of irec's (ex lists) */
3682
3683	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3684	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3685	while (erp_idx < nlists - 1) {
3686		erp = &ifp->if_u1.if_ext_irec[erp_idx];
3687		erp_next = erp + 1;
3688		if (erp_next->er_extcount <=
3689		    (XFS_LINEAR_EXTS - erp->er_extcount)) {
3690			memcpy(&erp->er_extbuf[erp->er_extcount],
3691				erp_next->er_extbuf, erp_next->er_extcount *
3692				sizeof(xfs_bmbt_rec_t));
3693			erp->er_extcount += erp_next->er_extcount;
3694			/*
3695			 * Free page before removing extent record
3696			 * so er_extoffs don't get modified in
3697			 * xfs_iext_irec_remove.
3698			 */
3699			kmem_free(erp_next->er_extbuf);
3700			erp_next->er_extbuf = NULL;
3701			xfs_iext_irec_remove(ifp, erp_idx + 1);
3702			nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3703		} else {
3704			erp_idx++;
3705		}
3706	}
3707}
3708
3709/*
3710 * This is called to update the er_extoff field in the indirection
3711 * array when extents have been added or removed from one of the
3712 * extent lists. erp_idx contains the irec index to begin updating
3713 * at and ext_diff contains the number of extents that were added
3714 * or removed.
3715 */
3716void
3717xfs_iext_irec_update_extoffs(
3718	xfs_ifork_t	*ifp,		/* inode fork pointer */
3719	int		erp_idx,	/* irec index to update */
3720	int		ext_diff)	/* number of new extents */
3721{
3722	int		i;		/* loop counter */
3723	int		nlists;		/* number of irec's (ex lists */
3724
3725	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
3726	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
3727	for (i = erp_idx; i < nlists; i++) {
3728		ifp->if_u1.if_ext_irec[i].er_extoff += ext_diff;
3729	}
3730}