xref: /freebsd-9.3-release/sys/gnu/fs/xfs/xfs_inode.c

/*
 * Copyright (c) 2000-2003 Silicon Graphics, Inc.  All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
 * Mountain View, CA  94043, or:
 *
 * http://www.sgi.com
 *
 * For further information regarding this notice, see:
 *
 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
 */

#include "xfs.h"
#include "xfs_macros.h"
#include "xfs_types.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_alloc_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_imap.h"
#include "xfs_alloc.h"
#include "xfs_ialloc.h"
#include "xfs_attr_sf.h"
#include "xfs_dir_sf.h"
#include "xfs_dir2_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode_item.h"
#include "xfs_inode.h"
#include "xfs_bmap.h"
#include "xfs_buf_item.h"
#include "xfs_rw.h"
#include "xfs_error.h"
#include "xfs_bit.h"
#include "xfs_utils.h"
#include "xfs_dir2_trace.h"
#include "xfs_quota.h"
#include "xfs_mac.h"
#include "xfs_acl.h"


kmem_zone_t *xfs_ifork_zone;
kmem_zone_t *xfs_inode_zone;
kmem_zone_t *xfs_chashlist_zone;

/*
 * Used in xfs_itruncate().  This is the maximum number of extents
 * freed from a file in a single transaction.
 */
#define	XFS_ITRUNC_MAX_EXTENTS	2

STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *);
STATIC int xfs_iformat_local(xfs_inode_t *, xfs_dinode_t *, int, int);
STATIC int xfs_iformat_extents(xfs_inode_t *, xfs_dinode_t *, int);
STATIC int xfs_iformat_btree(xfs_inode_t *, xfs_dinode_t *, int);


#ifdef DEBUG
/*
 * Make sure that the extents in the given memory buffer
 * are valid.
 */
STATIC void
xfs_validate_extents(
	xfs_bmbt_rec_t		*ep,
	int			nrecs,
	int			disk,
	xfs_exntfmt_t		fmt)
{
	xfs_bmbt_irec_t		irec;
	xfs_bmbt_rec_t		rec;
	int			i;

	for (i = 0; i < nrecs; i++) {
		rec.l0 = get_unaligned((__uint64_t*)&ep->l0);
		rec.l1 = get_unaligned((__uint64_t*)&ep->l1);
		if (disk)
			xfs_bmbt_disk_get_all(&rec, &irec);
		else
			xfs_bmbt_get_all(&rec, &irec);
		if (fmt == XFS_EXTFMT_NOSTATE)
			ASSERT(irec.br_state == XFS_EXT_NORM);
		ep++;
	}
}
#else /* DEBUG */
#define xfs_validate_extents(ep, nrecs, disk, fmt)
#endif /* DEBUG */

/*
 * Check that none of the inode's in the buffer have a next
 * unlinked field of 0.
 */
#if defined(DEBUG)
void
xfs_inobp_check(
	xfs_mount_t	*mp,
	xfs_buf_t	*bp)
{
	int		i;
	int		j;
	xfs_dinode_t	*dip;

	j = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;

	for (i = 0; i < j; i++) {
		dip = (xfs_dinode_t *)xfs_buf_offset(bp,
					i * mp->m_sb.sb_inodesize);
		if (INT_ISZERO(dip->di_next_unlinked, ARCH_CONVERT))  {
			xfs_fs_cmn_err(CE_ALERT, mp,
				"Detected a bogus zero next_unlinked field in incore inode buffer 0x%p.  About to pop an ASSERT.",
				bp);
			ASSERT(!INT_ISZERO(dip->di_next_unlinked, ARCH_CONVERT));
		}
	}
}
#endif

/*
 * This routine is called to map an inode number within a file
 * system to the buffer containing the on-disk version of the
 * inode.  It returns a pointer to the buffer containing the
 * on-disk inode in the bpp parameter, and in the dip parameter
 * it returns a pointer to the on-disk inode within that buffer.
 *
 * If a non-zero error is returned, then the contents of bpp and
 * dipp are undefined.
 *
 * Use xfs_imap() to determine the size and location of the
 * buffer to read from disk.
 */
int
xfs_inotobp(
	xfs_mount_t	*mp,
	xfs_trans_t	*tp,
	xfs_ino_t	ino,
	xfs_dinode_t	**dipp,
	xfs_buf_t	**bpp,
	int		*offset)
{
	int		di_ok;
	xfs_imap_t	imap;
	xfs_buf_t	*bp;
	int		error;
	xfs_dinode_t	*dip;

	/*
	 * Call the space managment code to find the location of the
	 * inode on disk.
	 */
	imap.im_blkno = 0;
	error = xfs_imap(mp, tp, ino, &imap, XFS_IMAP_LOOKUP);
	if (error != 0) {
		cmn_err(CE_WARN,
	"xfs_inotobp: xfs_imap()  returned an "
	"error %d on %s.  Returning error.", error, mp->m_fsname);
		return error;
	}

	/*
	 * If the inode number maps to a block outside the bounds of the
	 * file system then return NULL rather than calling read_buf
	 * and panicing when we get an error from the driver.
	 */
	if ((imap.im_blkno + imap.im_len) >
	    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
		cmn_err(CE_WARN,
	"xfs_inotobp: inode number (%d + %d) maps to a block outside the bounds "
	"of the file system %s.  Returning EINVAL.",
			imap.im_blkno, imap.im_len,mp->m_fsname);
		return XFS_ERROR(EINVAL);
	}

	/*
	 * Read in the buffer.  If tp is NULL, xfs_trans_read_buf() will
	 * default to just a read_buf() call.
	 */
	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap.im_blkno,
				   (int)imap.im_len, XFS_BUF_LOCK, &bp);

	if (error) {
		cmn_err(CE_WARN,
	"xfs_inotobp: xfs_trans_read_buf()  returned an "
	"error %d on %s.  Returning error.", error, mp->m_fsname);
		return error;
	}
	dip = (xfs_dinode_t *)xfs_buf_offset(bp, 0);
	di_ok =
		INT_GET(dip->di_core.di_magic, ARCH_CONVERT) == XFS_DINODE_MAGIC &&
		XFS_DINODE_GOOD_VERSION(INT_GET(dip->di_core.di_version, ARCH_CONVERT));
	if (unlikely(XFS_TEST_ERROR(!di_ok, mp, XFS_ERRTAG_ITOBP_INOTOBP,
			XFS_RANDOM_ITOBP_INOTOBP))) {
		XFS_CORRUPTION_ERROR("xfs_inotobp", XFS_ERRLEVEL_LOW, mp, dip);
		xfs_trans_brelse(tp, bp);
		cmn_err(CE_WARN,
	"xfs_inotobp: XFS_TEST_ERROR()  returned an "
	"error on %s.  Returning EFSCORRUPTED.",  mp->m_fsname);
		return XFS_ERROR(EFSCORRUPTED);
	}

	xfs_inobp_check(mp, bp);

	/*
	 * Set *dipp to point to the on-disk inode in the buffer.
	 */
	*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
	*bpp = bp;
	*offset = imap.im_boffset;
	return 0;
}


/*
 * This routine is called to map an inode to the buffer containing
 * the on-disk version of the inode.  It returns a pointer to the
 * buffer containing the on-disk inode in the bpp parameter, and in
 * the dip parameter it returns a pointer to the on-disk inode within
 * that buffer.
 *
 * If a non-zero error is returned, then the contents of bpp and
 * dipp are undefined.
 *
 * If the inode is new and has not yet been initialized, use xfs_imap()
 * to determine the size and location of the buffer to read from disk.
 * If the inode has already been mapped to its buffer and read in once,
 * then use the mapping information stored in the inode rather than
 * calling xfs_imap().  This allows us to avoid the overhead of looking
 * at the inode btree for small block file systems (see xfs_dilocate()).
 * We can tell whether the inode has been mapped in before by comparing
 * its disk block address to 0.  Only uninitialized inodes will have
 * 0 for the disk block address.
 */
int
xfs_itobp(
	xfs_mount_t	*mp,
	xfs_trans_t	*tp,
	xfs_inode_t	*ip,
	xfs_dinode_t	**dipp,
	xfs_buf_t	**bpp,
	xfs_daddr_t	bno)
{
	xfs_buf_t	*bp;
	int		error;
	xfs_imap_t	imap;
#ifdef __KERNEL__
	int		i;
	int		ni;
#endif

	if (ip->i_blkno == (xfs_daddr_t)0) {
		/*
		 * Call the space management code to find the location of the
		 * inode on disk.
		 */
		imap.im_blkno = bno;
		error = xfs_imap(mp, tp, ip->i_ino, &imap, XFS_IMAP_LOOKUP);
		if (error != 0) {
			return error;
		}

		/*
		 * If the inode number maps to a block outside the bounds
		 * of the file system then return NULL rather than calling
		 * read_buf and panicing when we get an error from the
		 * driver.
		 */
		if ((imap.im_blkno + imap.im_len) >
		    XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
#ifdef DEBUG
			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_itobp: "
					"(imap.im_blkno (0x%llx) "
					"+ imap.im_len (0x%llx)) > "
					" XFS_FSB_TO_BB(mp, "
					"mp->m_sb.sb_dblocks) (0x%llx)",
					(unsigned long long) imap.im_blkno,
					(unsigned long long) imap.im_len,
					XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
#endif /* DEBUG */
			return XFS_ERROR(EINVAL);
		}

		/*
		 * Fill in the fields in the inode that will be used to
		 * map the inode to its buffer from now on.
		 */
		ip->i_blkno = imap.im_blkno;
		ip->i_len = imap.im_len;
		ip->i_boffset = imap.im_boffset;
	} else {
		/*
		 * We've already mapped the inode once, so just use the
		 * mapping that we saved the first time.
		 */
		imap.im_blkno = ip->i_blkno;
		imap.im_len = ip->i_len;
		imap.im_boffset = ip->i_boffset;
	}
	ASSERT(bno == 0 || bno == imap.im_blkno);

	/*
	 * Read in the buffer.  If tp is NULL, xfs_trans_read_buf() will
	 * default to just a read_buf() call.
	 */
	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap.im_blkno,
				   (int)imap.im_len, XFS_BUF_LOCK, &bp);

	if (error) {
#ifdef DEBUG
		xfs_fs_cmn_err(CE_ALERT, mp, "xfs_itobp: "
				"xfs_trans_read_buf() returned error %d, "
				"imap.im_blkno 0x%llx, imap.im_len 0x%llx",
				error, (unsigned long long) imap.im_blkno,
				(unsigned long long) imap.im_len);
#endif /* DEBUG */
		return error;
	}
#ifdef __KERNEL__
	/*
	 * Validate the magic number and version of every inode in the buffer
	 * (if DEBUG kernel) or the first inode in the buffer, otherwise.
	 */
#ifdef DEBUG
	ni = BBTOB(imap.im_len) >> mp->m_sb.sb_inodelog;
#else
	ni = 1;
#endif
	for (i = 0; i < ni; i++) {
		int		di_ok;
		xfs_dinode_t	*dip;

		dip = (xfs_dinode_t *)xfs_buf_offset(bp,
					(i << mp->m_sb.sb_inodelog));
		di_ok = INT_GET(dip->di_core.di_magic, ARCH_CONVERT) == XFS_DINODE_MAGIC &&
			    XFS_DINODE_GOOD_VERSION(INT_GET(dip->di_core.di_version, ARCH_CONVERT));
		if (unlikely(XFS_TEST_ERROR(!di_ok, mp, XFS_ERRTAG_ITOBP_INOTOBP,
				 XFS_RANDOM_ITOBP_INOTOBP))) {
#ifdef DEBUG
			prdev("bad inode magic/vsn daddr %lld #%d (magic=%x)",
				mp->m_ddev_targp,
				(unsigned long long)imap.im_blkno, i,
				INT_GET(dip->di_core.di_magic, ARCH_CONVERT));
#endif
			XFS_CORRUPTION_ERROR("xfs_itobp", XFS_ERRLEVEL_HIGH,
					     mp, dip);
			xfs_trans_brelse(tp, bp);
			return XFS_ERROR(EFSCORRUPTED);
		}
	}
#endif	/* __KERNEL__ */

	xfs_inobp_check(mp, bp);

	/*
	 * Mark the buffer as an inode buffer now that it looks good
	 */
	XFS_BUF_SET_VTYPE(bp, B_FS_INO);

	/*
	 * Set *dipp to point to the on-disk inode in the buffer.
	 */
	*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
	*bpp = bp;
	return 0;
}

/*
 * Move inode type and inode format specific information from the
 * on-disk inode to the in-core inode.  For fifos, devs, and sockets
 * this means set if_rdev to the proper value.  For files, directories,
 * and symlinks this means to bring in the in-line data or extent
 * pointers.  For a file in B-tree format, only the root is immediately
 * brought in-core.  The rest will be in-lined in if_extents when it
 * is first referenced (see xfs_iread_extents()).
 */
STATIC int
xfs_iformat(
	xfs_inode_t		*ip,
	xfs_dinode_t		*dip)
{
	xfs_attr_shortform_t	*atp;
	int			size;
	int			error;
	xfs_fsize_t             di_size;
	ip->i_df.if_ext_max =
		XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
	error = 0;

	if (unlikely(
	    INT_GET(dip->di_core.di_nextents, ARCH_CONVERT) +
		INT_GET(dip->di_core.di_anextents, ARCH_CONVERT) >
	    INT_GET(dip->di_core.di_nblocks, ARCH_CONVERT))) {
		xfs_fs_cmn_err(CE_WARN, ip->i_mount,
			"corrupt dinode %Lu, extent total = %d, nblocks = %Lu."
			"  Unmount and run xfs_repair.",
			(unsigned long long)ip->i_ino,
			(int)(INT_GET(dip->di_core.di_nextents, ARCH_CONVERT)
			    + INT_GET(dip->di_core.di_anextents, ARCH_CONVERT)),
			(unsigned long long)
			INT_GET(dip->di_core.di_nblocks, ARCH_CONVERT));
		XFS_CORRUPTION_ERROR("xfs_iformat(1)", XFS_ERRLEVEL_LOW,
				     ip->i_mount, dip);
		return XFS_ERROR(EFSCORRUPTED);
	}

	if (unlikely(INT_GET(dip->di_core.di_forkoff, ARCH_CONVERT) > ip->i_mount->m_sb.sb_inodesize)) {
		xfs_fs_cmn_err(CE_WARN, ip->i_mount,
			"corrupt dinode %Lu, forkoff = 0x%x."
			"  Unmount and run xfs_repair.",
			(unsigned long long)ip->i_ino,
			(int)(INT_GET(dip->di_core.di_forkoff, ARCH_CONVERT)));
		XFS_CORRUPTION_ERROR("xfs_iformat(2)", XFS_ERRLEVEL_LOW,
				     ip->i_mount, dip);
		return XFS_ERROR(EFSCORRUPTED);
	}

	switch (ip->i_d.di_mode & S_IFMT) {
	case S_IFIFO:
	case S_IFCHR:
	case S_IFBLK:
	case S_IFSOCK:
		if (unlikely(INT_GET(dip->di_core.di_format, ARCH_CONVERT) != XFS_DINODE_FMT_DEV)) {
			XFS_CORRUPTION_ERROR("xfs_iformat(3)", XFS_ERRLEVEL_LOW,
					      ip->i_mount, dip);
			return XFS_ERROR(EFSCORRUPTED);
		}
		ip->i_d.di_size = 0;
		ip->i_df.if_u2.if_rdev = INT_GET(dip->di_u.di_dev, ARCH_CONVERT);
		break;

	case S_IFREG:
	case S_IFLNK:
	case S_IFDIR:
		switch (INT_GET(dip->di_core.di_format, ARCH_CONVERT)) {
		case XFS_DINODE_FMT_LOCAL:
			/*
			 * no local regular files yet
			 */
			if (unlikely((INT_GET(dip->di_core.di_mode, ARCH_CONVERT) & S_IFMT) == S_IFREG)) {
				xfs_fs_cmn_err(CE_WARN, ip->i_mount,
					"corrupt inode (local format for regular file) %Lu.  Unmount and run xfs_repair.",
					(unsigned long long) ip->i_ino);
				XFS_CORRUPTION_ERROR("xfs_iformat(4)",
						     XFS_ERRLEVEL_LOW,
						     ip->i_mount, dip);
				return XFS_ERROR(EFSCORRUPTED);
			}

			di_size = INT_GET(dip->di_core.di_size, ARCH_CONVERT);
			if (unlikely(di_size >
			    XFS_DFORK_DSIZE_ARCH(dip, ip->i_mount, ARCH_CONVERT))) {
				xfs_fs_cmn_err(CE_WARN, ip->i_mount,
					"corrupt inode %Lu (bad size %Ld for local inode).  Unmount and run xfs_repair.",
					(unsigned long long) ip->i_ino,
					(long long) di_size);
				XFS_CORRUPTION_ERROR("xfs_iformat(5)",
						     XFS_ERRLEVEL_LOW,
						     ip->i_mount, dip);
				return XFS_ERROR(EFSCORRUPTED);
			}

			size = (int)di_size;
			error = xfs_iformat_local(ip, dip, XFS_DATA_FORK, size);
			break;
		case XFS_DINODE_FMT_EXTENTS:
			error = xfs_iformat_extents(ip, dip, XFS_DATA_FORK);
			break;
		case XFS_DINODE_FMT_BTREE:
			error = xfs_iformat_btree(ip, dip, XFS_DATA_FORK);
			break;
		default:
			XFS_ERROR_REPORT("xfs_iformat(6)", XFS_ERRLEVEL_LOW,
					 ip->i_mount);
			return XFS_ERROR(EFSCORRUPTED);
		}
		break;

	default:
		XFS_ERROR_REPORT("xfs_iformat(7)", XFS_ERRLEVEL_LOW, ip->i_mount);
		return XFS_ERROR(EFSCORRUPTED);
	}
	if (error) {
		return error;
	}
	if (!XFS_DFORK_Q_ARCH(dip, ARCH_CONVERT))
		return 0;
	ASSERT(ip->i_afp == NULL);
	ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP);
	ip->i_afp->if_ext_max =
		XFS_IFORK_ASIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
	switch (INT_GET(dip->di_core.di_aformat, ARCH_CONVERT)) {
	case XFS_DINODE_FMT_LOCAL:
		atp = (xfs_attr_shortform_t *)XFS_DFORK_APTR_ARCH(dip, ARCH_CONVERT);
		size = (int)INT_GET(atp->hdr.totsize, ARCH_CONVERT);
		error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, size);
		break;
	case XFS_DINODE_FMT_EXTENTS:
		error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK);
		break;
	case XFS_DINODE_FMT_BTREE:
		error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK);
		break;
	default:
		error = XFS_ERROR(EFSCORRUPTED);
		break;
	}
	if (error) {
		kmem_zone_free(xfs_ifork_zone, ip->i_afp);
		ip->i_afp = NULL;
		xfs_idestroy_fork(ip, XFS_DATA_FORK);
	}
	return error;
}

/*
 * The file is in-lined in the on-disk inode.
 * If it fits into if_inline_data, then copy
 * it there, otherwise allocate a buffer for it
 * and copy the data there.  Either way, set
 * if_data to point at the data.
 * If we allocate a buffer for the data, make
 * sure that its size is a multiple of 4 and
 * record the real size in i_real_bytes.
 */
STATIC int
xfs_iformat_local(
	xfs_inode_t	*ip,
	xfs_dinode_t	*dip,
	int		whichfork,
	int		size)
{
	xfs_ifork_t	*ifp;
	int		real_size;

	/*
	 * If the size is unreasonable, then something
	 * is wrong and we just bail out rather than crash in
	 * kmem_alloc() or memcpy() below.
	 */
	if (unlikely(size > XFS_DFORK_SIZE_ARCH(dip, ip->i_mount, whichfork, ARCH_CONVERT))) {
		xfs_fs_cmn_err(CE_WARN, ip->i_mount,
			"corrupt inode %Lu (bad size %d for local fork, size = %d).  Unmount and run xfs_repair.",
			(unsigned long long) ip->i_ino, size,
			XFS_DFORK_SIZE_ARCH(dip, ip->i_mount, whichfork, ARCH_CONVERT));
		XFS_CORRUPTION_ERROR("xfs_iformat_local", XFS_ERRLEVEL_LOW,
				     ip->i_mount, dip);
		return XFS_ERROR(EFSCORRUPTED);
	}
	ifp = XFS_IFORK_PTR(ip, whichfork);
	real_size = 0;
	if (size == 0)
		ifp->if_u1.if_data = NULL;
	else if (size <= sizeof(ifp->if_u2.if_inline_data))
		ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
	else {
		real_size = roundup(size, 4);
		ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP);
	}
	ifp->if_bytes = size;
	ifp->if_real_bytes = real_size;
	if (size)
		memcpy(ifp->if_u1.if_data,
			XFS_DFORK_PTR_ARCH(dip, whichfork, ARCH_CONVERT), size);
	ifp->if_flags &= ~XFS_IFEXTENTS;
	ifp->if_flags |= XFS_IFINLINE;
	return 0;
}

/*
 * The file consists of a set of extents all
 * of which fit into the on-disk inode.
 * If there are few enough extents to fit into
 * the if_inline_ext, then copy them there.
 * Otherwise allocate a buffer for them and copy
 * them into it.  Either way, set if_extents
 * to point at the extents.
 */
STATIC int
xfs_iformat_extents(
	xfs_inode_t	*ip,
	xfs_dinode_t	*dip,
	int		whichfork)
{
	xfs_bmbt_rec_t	*ep, *dp;
	xfs_ifork_t	*ifp;
	int		nex;
	int		real_size;
	int		size;
	int		i;

	ifp = XFS_IFORK_PTR(ip, whichfork);
	nex = XFS_DFORK_NEXTENTS_ARCH(dip, whichfork, ARCH_CONVERT);
	size = nex * (uint)sizeof(xfs_bmbt_rec_t);

	/*
	 * If the number of extents is unreasonable, then something
	 * is wrong and we just bail out rather than crash in
	 * kmem_alloc() or memcpy() below.
	 */
	if (unlikely(size < 0 || size > XFS_DFORK_SIZE_ARCH(dip, ip->i_mount, whichfork, ARCH_CONVERT))) {
		xfs_fs_cmn_err(CE_WARN, ip->i_mount,
			"corrupt inode %Lu ((a)extents = %d).  Unmount and run xfs_repair.",
			(unsigned long long) ip->i_ino, nex);
		XFS_CORRUPTION_ERROR("xfs_iformat_extents(1)", XFS_ERRLEVEL_LOW,
				     ip->i_mount, dip);
		return XFS_ERROR(EFSCORRUPTED);
	}

	real_size = 0;
	if (nex == 0)
		ifp->if_u1.if_extents = NULL;
	else if (nex <= XFS_INLINE_EXTS)
		ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
	else {
		ifp->if_u1.if_extents = kmem_alloc(size, KM_SLEEP);
		ASSERT(ifp->if_u1.if_extents != NULL);
		real_size = size;
	}
	ifp->if_bytes = size;
	ifp->if_real_bytes = real_size;
	if (size) {
		dp = (xfs_bmbt_rec_t *)
			XFS_DFORK_PTR_ARCH(dip, whichfork, ARCH_CONVERT);
		xfs_validate_extents(dp, nex, 1, XFS_EXTFMT_INODE(ip));
		ep = ifp->if_u1.if_extents;
		for (i = 0; i < nex; i++, ep++, dp++) {
			ep->l0 = INT_GET(get_unaligned((__uint64_t*)&dp->l0),
								ARCH_CONVERT);
			ep->l1 = INT_GET(get_unaligned((__uint64_t*)&dp->l1),
								ARCH_CONVERT);
		}
		xfs_bmap_trace_exlist("xfs_iformat_extents", ip, nex,
			whichfork);
		if (whichfork != XFS_DATA_FORK ||
			XFS_EXTFMT_INODE(ip) == XFS_EXTFMT_NOSTATE)
				if (unlikely(xfs_check_nostate_extents(
				    ifp->if_u1.if_extents, nex))) {
					XFS_ERROR_REPORT("xfs_iformat_extents(2)",
							 XFS_ERRLEVEL_LOW,
							 ip->i_mount);
					return XFS_ERROR(EFSCORRUPTED);
				}
	}
	ifp->if_flags |= XFS_IFEXTENTS;
	return 0;
}

/*
 * The file has too many extents to fit into
 * the inode, so they are in B-tree format.
 * Allocate a buffer for the root of the B-tree
 * and copy the root into it.  The i_extents
 * field will remain NULL until all of the
 * extents are read in (when they are needed).
 */
STATIC int
xfs_iformat_btree(
	xfs_inode_t		*ip,
	xfs_dinode_t		*dip,
	int			whichfork)
{
	xfs_bmdr_block_t	*dfp;
	xfs_ifork_t		*ifp;
	/* REFERENCED */
	int			nrecs;
	int			size;

	ifp = XFS_IFORK_PTR(ip, whichfork);
	dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR_ARCH(dip, whichfork, ARCH_CONVERT);
	size = XFS_BMAP_BROOT_SPACE(dfp);
	nrecs = XFS_BMAP_BROOT_NUMRECS(dfp);

	/*
	 * blow out if -- fork has less extents than can fit in
	 * fork (fork shouldn't be a btree format), root btree
	 * block has more records than can fit into the fork,
	 * or the number of extents is greater than the number of
	 * blocks.
	 */
	if (unlikely(XFS_IFORK_NEXTENTS(ip, whichfork) <= ifp->if_ext_max
	    || XFS_BMDR_SPACE_CALC(nrecs) >
			XFS_DFORK_SIZE_ARCH(dip, ip->i_mount, whichfork, ARCH_CONVERT)
	    || XFS_IFORK_NEXTENTS(ip, whichfork) > ip->i_d.di_nblocks)) {
		xfs_fs_cmn_err(CE_WARN, ip->i_mount,
			"corrupt inode %Lu (btree).  Unmount and run xfs_repair.",
			(unsigned long long) ip->i_ino);
		XFS_ERROR_REPORT("xfs_iformat_btree", XFS_ERRLEVEL_LOW,
				 ip->i_mount);
		return XFS_ERROR(EFSCORRUPTED);
	}

	ifp->if_broot_bytes = size;
	ifp->if_broot = kmem_alloc(size, KM_SLEEP);
	ASSERT(ifp->if_broot != NULL);
	/*
	 * Copy and convert from the on-disk structure
	 * to the in-memory structure.
	 */
	xfs_bmdr_to_bmbt(dfp, XFS_DFORK_SIZE_ARCH(dip, ip->i_mount, whichfork, ARCH_CONVERT),
		ifp->if_broot, size);
	ifp->if_flags &= ~XFS_IFEXTENTS;
	ifp->if_flags |= XFS_IFBROOT;

	return 0;
}

/*
 * xfs_xlate_dinode_core - translate an xfs_inode_core_t between ondisk
 * and native format
 *
 * buf  = on-disk representation
 * dip  = native representation
 * dir  = direction - +ve -> disk to native
 *                    -ve -> native to disk
 * arch = on-disk architecture
 */
void
xfs_xlate_dinode_core(
	xfs_caddr_t		buf,
	xfs_dinode_core_t	*dip,
	int			dir,
	xfs_arch_t		arch)
{
	xfs_dinode_core_t	*buf_core = (xfs_dinode_core_t *)buf;
	xfs_dinode_core_t	*mem_core = (xfs_dinode_core_t *)dip;

	ASSERT(dir);
	if (arch == ARCH_NOCONVERT) {
		if (dir > 0) {
			memcpy((xfs_caddr_t)mem_core, (xfs_caddr_t)buf_core,
				sizeof(xfs_dinode_core_t));
		} else {
			memcpy((xfs_caddr_t)buf_core, (xfs_caddr_t)mem_core,
				sizeof(xfs_dinode_core_t));
		}
		return;
	}

	INT_XLATE(buf_core->di_magic, mem_core->di_magic, dir, arch);
	INT_XLATE(buf_core->di_mode, mem_core->di_mode, dir, arch);
	INT_XLATE(buf_core->di_version,	mem_core->di_version, dir, arch);
	INT_XLATE(buf_core->di_format, mem_core->di_format, dir, arch);
	INT_XLATE(buf_core->di_onlink, mem_core->di_onlink, dir, arch);
	INT_XLATE(buf_core->di_uid, mem_core->di_uid, dir, arch);
	INT_XLATE(buf_core->di_gid, mem_core->di_gid, dir, arch);
	INT_XLATE(buf_core->di_nlink, mem_core->di_nlink, dir, arch);
	INT_XLATE(buf_core->di_projid, mem_core->di_projid, dir, arch);

	if (dir > 0) {
		memcpy(mem_core->di_pad, buf_core->di_pad,
			sizeof(buf_core->di_pad));
	} else {
		memcpy(buf_core->di_pad, mem_core->di_pad,
			sizeof(buf_core->di_pad));
	}

	INT_XLATE(buf_core->di_flushiter, mem_core->di_flushiter, dir, arch);

	INT_XLATE(buf_core->di_atime.t_sec, mem_core->di_atime.t_sec,
			dir, arch);
	INT_XLATE(buf_core->di_atime.t_nsec, mem_core->di_atime.t_nsec,
			dir, arch);
	INT_XLATE(buf_core->di_mtime.t_sec, mem_core->di_mtime.t_sec,
			dir, arch);
	INT_XLATE(buf_core->di_mtime.t_nsec, mem_core->di_mtime.t_nsec,
			dir, arch);
	INT_XLATE(buf_core->di_ctime.t_sec, mem_core->di_ctime.t_sec,
			dir, arch);
	INT_XLATE(buf_core->di_ctime.t_nsec, mem_core->di_ctime.t_nsec,
			dir, arch);
	INT_XLATE(buf_core->di_size, mem_core->di_size, dir, arch);
	INT_XLATE(buf_core->di_nblocks, mem_core->di_nblocks, dir, arch);
	INT_XLATE(buf_core->di_extsize, mem_core->di_extsize, dir, arch);
	INT_XLATE(buf_core->di_nextents, mem_core->di_nextents, dir, arch);
	INT_XLATE(buf_core->di_anextents, mem_core->di_anextents, dir, arch);
	INT_XLATE(buf_core->di_forkoff, mem_core->di_forkoff, dir, arch);
	INT_XLATE(buf_core->di_aformat, mem_core->di_aformat, dir, arch);
	INT_XLATE(buf_core->di_dmevmask, mem_core->di_dmevmask, dir, arch);
	INT_XLATE(buf_core->di_dmstate, mem_core->di_dmstate, dir, arch);
	INT_XLATE(buf_core->di_flags, mem_core->di_flags, dir, arch);
	INT_XLATE(buf_core->di_gen, mem_core->di_gen, dir, arch);
}

/*
 * Given a mount structure and an inode number, return a pointer
 * to a newly allocated in-core inode coresponding to the given
 * inode number.
 *
 * Initialize the inode's attributes and extent pointers if it
 * already has them (it will not if the inode has no links).
 */
int
xfs_iread(
	xfs_mount_t	*mp,
	xfs_trans_t	*tp,
	xfs_ino_t	ino,
	xfs_inode_t	**ipp,
	xfs_daddr_t	bno)
{
	xfs_buf_t	*bp;
	xfs_dinode_t	*dip;
	xfs_inode_t	*ip;
	int		error;

	ASSERT(xfs_inode_zone != NULL);

	ip = kmem_zone_zalloc(xfs_inode_zone, KM_SLEEP);
	ip->i_ino = ino;
	ip->i_mount = mp;

	/*
	 * Get pointer's to the on-disk inode and the buffer containing it.
	 * If the inode number refers to a block outside the file system
	 * then xfs_itobp() will return NULL.  In this case we should
	 * return NULL as well.  Set i_blkno to 0 so that xfs_itobp() will
	 * know that this is a new incore inode.
	 */
	error = xfs_itobp(mp, tp, ip, &dip, &bp, bno);

	if (error != 0) {
		kmem_zone_free(xfs_inode_zone, ip);
		return error;
	}

	/*
	 * Initialize inode's trace buffers.
	 * Do this before xfs_iformat in case it adds entries.
	 */
#ifdef XFS_BMAP_TRACE
	ip->i_xtrace = ktrace_alloc(XFS_BMAP_KTRACE_SIZE, KM_SLEEP);
#endif
#ifdef XFS_BMBT_TRACE
	ip->i_btrace = ktrace_alloc(XFS_BMBT_KTRACE_SIZE, KM_SLEEP);
#endif
#ifdef XFS_RW_TRACE
	ip->i_rwtrace = ktrace_alloc(XFS_RW_KTRACE_SIZE, KM_SLEEP);
#endif
#ifdef XFS_ILOCK_TRACE
	ip->i_lock_trace = ktrace_alloc(XFS_ILOCK_KTRACE_SIZE, KM_SLEEP);
#endif
#ifdef XFS_DIR2_TRACE
	ip->i_dir_trace = ktrace_alloc(XFS_DIR2_KTRACE_SIZE, KM_SLEEP);
#endif

	/*
	 * If we got something that isn't an inode it means someone
	 * (nfs or dmi) has a stale handle.
	 */
	if (INT_GET(dip->di_core.di_magic, ARCH_CONVERT) != XFS_DINODE_MAGIC) {
		kmem_zone_free(xfs_inode_zone, ip);
		xfs_trans_brelse(tp, bp);
#ifdef DEBUG
		xfs_fs_cmn_err(CE_ALERT, mp, "xfs_iread: "
				"dip->di_core.di_magic (0x%x) != "
				"XFS_DINODE_MAGIC (0x%x)",
				INT_GET(dip->di_core.di_magic, ARCH_CONVERT),
				XFS_DINODE_MAGIC);
#endif /* DEBUG */
		return XFS_ERROR(EINVAL);
	}

	/*
	 * If the on-disk inode is already linked to a directory
	 * entry, copy all of the inode into the in-core inode.
	 * xfs_iformat() handles copying in the inode format
	 * specific information.
	 * Otherwise, just get the truly permanent information.
	 */
	if (!INT_ISZERO(dip->di_core.di_mode, ARCH_CONVERT)) {
		xfs_xlate_dinode_core((xfs_caddr_t)&dip->di_core,
		     &(ip->i_d), 1, ARCH_CONVERT);
		error = xfs_iformat(ip, dip);
		if (error)  {
			kmem_zone_free(xfs_inode_zone, ip);
			xfs_trans_brelse(tp, bp);
#ifdef DEBUG
			xfs_fs_cmn_err(CE_ALERT, mp, "xfs_iread: "
					"xfs_iformat() returned error %d",
					error);
#endif /* DEBUG */
			return error;
		}
	} else {
		ip->i_d.di_magic = INT_GET(dip->di_core.di_magic, ARCH_CONVERT);
		ip->i_d.di_version = INT_GET(dip->di_core.di_version, ARCH_CONVERT);
		ip->i_d.di_gen = INT_GET(dip->di_core.di_gen, ARCH_CONVERT);
		ip->i_d.di_flushiter = INT_GET(dip->di_core.di_flushiter, ARCH_CONVERT);
		/*
		 * Make sure to pull in the mode here as well in
		 * case the inode is released without being used.
		 * This ensures that xfs_inactive() will see that
		 * the inode is already free and not try to mess
		 * with the uninitialized part of it.
		 */
		ip->i_d.di_mode = 0;
		/*
		 * Initialize the per-fork minima and maxima for a new
		 * inode here.  xfs_iformat will do it for old inodes.
		 */
		ip->i_df.if_ext_max =
			XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
	}

	/* XXXKAN: initialize i_reclaim */
	bzero(&ip->i_reclaim, sizeof(&ip->i_reclaim));

	/*
	 * The inode format changed when we moved the link count and
	 * made it 32 bits long.  If this is an old format inode,
	 * convert it in memory to look like a new one.  If it gets
	 * flushed to disk we will convert back before flushing or
	 * logging it.  We zero out the new projid field and the old link
	 * count field.  We'll handle clearing the pad field (the remains
	 * of the old uuid field) when we actually convert the inode to
	 * the new format. We don't change the version number so that we
	 * can distinguish this from a real new format inode.
	 */
	if (ip->i_d.di_version == XFS_DINODE_VERSION_1) {
		ip->i_d.di_nlink = ip->i_d.di_onlink;
		ip->i_d.di_onlink = 0;
		ip->i_d.di_projid = 0;
	}

	ip->i_delayed_blks = 0;

	/*
	 * Mark the buffer containing the inode as something to keep
	 * around for a while.  This helps to keep recently accessed
	 * meta-data in-core longer.
	 */
	 XFS_BUF_SET_REF(bp, XFS_INO_REF);

	/*
	 * Use xfs_trans_brelse() to release the buffer containing the
	 * on-disk inode, because it was acquired with xfs_trans_read_buf()
	 * in xfs_itobp() above.  If tp is NULL, this is just a normal
	 * brelse().  If we're within a transaction, then xfs_trans_brelse()
	 * will only release the buffer if it is not dirty within the
	 * transaction.  It will be OK to release the buffer in this case,
	 * because inodes on disk are never destroyed and we will be
	 * locking the new in-core inode before putting it in the hash
	 * table where other processes can find it.  Thus we don't have
	 * to worry about the inode being changed just because we released
	 * the buffer.
	 */
	xfs_trans_brelse(tp, bp);
	*ipp = ip;
	return 0;
}

/*
 * Read in extents from a btree-format inode.
 * Allocate and fill in if_extents.  Real work is done in xfs_bmap.c.
 */
int
xfs_iread_extents(
	xfs_trans_t	*tp,
	xfs_inode_t	*ip,
	int		whichfork)
{
	int		error;
	xfs_ifork_t	*ifp;
	size_t		size;

	if (unlikely(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
		XFS_ERROR_REPORT("xfs_iread_extents", XFS_ERRLEVEL_LOW,
				 ip->i_mount);
		return XFS_ERROR(EFSCORRUPTED);
	}
	size = XFS_IFORK_NEXTENTS(ip, whichfork) * (uint)sizeof(xfs_bmbt_rec_t);
	ifp = XFS_IFORK_PTR(ip, whichfork);
	/*
	 * We know that the size is valid (it's checked in iformat_btree)
	 */
	ifp->if_u1.if_extents = kmem_alloc(size, KM_SLEEP);
	ASSERT(ifp->if_u1.if_extents != NULL);
	ifp->if_lastex = NULLEXTNUM;
	ifp->if_bytes = ifp->if_real_bytes = (int)size;
	ifp->if_flags |= XFS_IFEXTENTS;
	error = xfs_bmap_read_extents(tp, ip, whichfork);
	if (error) {
		kmem_free(ifp->if_u1.if_extents, size);
		ifp->if_u1.if_extents = NULL;
		ifp->if_bytes = ifp->if_real_bytes = 0;
		ifp->if_flags &= ~XFS_IFEXTENTS;
		return error;
	}
	xfs_validate_extents((xfs_bmbt_rec_t *)ifp->if_u1.if_extents,
		XFS_IFORK_NEXTENTS(ip, whichfork), 0, XFS_EXTFMT_INODE(ip));
	return 0;
}

/*
 * Allocate an inode on disk and return a copy of its in-core version.
 * The in-core inode is locked exclusively.  Set mode, nlink, and rdev
 * appropriately within the inode.  The uid and gid for the inode are
 * set according to the contents of the given cred structure.
 *
 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
 * has a free inode available, call xfs_iget()
 * to obtain the in-core version of the allocated inode.  Finally,
 * fill in the inode and log its initial contents.  In this case,
 * ialloc_context would be set to NULL and call_again set to false.
 *
 * If xfs_dialloc() does not have an available inode,
 * it will replenish its supply by doing an allocation. Since we can
 * only do one allocation within a transaction without deadlocks, we
 * must commit the current transaction before returning the inode itself.
 * In this case, therefore, we will set call_again to true and return.
 * The caller should then commit the current transaction, start a new
 * transaction, and call xfs_ialloc() again to actually get the inode.
 *
 * To ensure that some other process does not grab the inode that
 * was allocated during the first call to xfs_ialloc(), this routine
 * also returns the [locked] bp pointing to the head of the freelist
 * as ialloc_context.  The caller should hold this buffer across
 * the commit and pass it back into this routine on the second call.
 */
int
xfs_ialloc(
	xfs_trans_t	*tp,
	xfs_inode_t	*pip,
	mode_t		mode,
	nlink_t		nlink,
	xfs_dev_t	rdev,
	cred_t		*cr,
	xfs_prid_t	prid,
	int		okalloc,
	xfs_buf_t	**ialloc_context,
	boolean_t	*call_again,
	xfs_inode_t	**ipp)
{
	xfs_ino_t	ino;
	xfs_inode_t	*ip;
	xfs_vnode_t	*vp;
	uint		flags;
	int		error;

	/*
	 * Call the space management code to pick
	 * the on-disk inode to be allocated.
	 */
	ASSERT(pip != NULL);
	error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
			    ialloc_context, call_again, &ino);
	if (error != 0) {
		return error;
	}
	if (*call_again || ino == NULLFSINO) {
		*ipp = NULL;
		return 0;
	}
	ASSERT(*ialloc_context == NULL);

	/*
	 * Get the in-core inode with the lock held exclusively.
	 * This is because we're setting fields here we need
	 * to prevent others from looking at until we're done.
	 */
	error = xfs_trans_iget(tp->t_mountp, tp, ino, XFS_ILOCK_EXCL, &ip);
	if (error != 0) {
		return error;
	}
	ASSERT(ip != NULL);
	vp = XFS_ITOV(ip);
	ASSERT(vp != NULL);
	vp->v_type = IFTOVT(mode);
	ip->i_d.di_mode = (__uint16_t)mode;
	ip->i_d.di_onlink = 0;
	ip->i_d.di_nlink = nlink;
	ASSERT(ip->i_d.di_nlink == nlink);
	ip->i_d.di_uid = curthread->td_ucred->cr_uid;
	ip->i_d.di_gid = curthread->td_ucred->cr_groups[0];
	ip->i_d.di_projid = prid;
	memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));

	/*
	 * If the superblock version is up to where we support new format
	 * inodes and this is currently an old format inode, then change
	 * the inode version number now.  This way we only do the conversion
	 * here rather than here and in the flush/logging code.
	 */
	if (XFS_SB_VERSION_HASNLINK(&tp->t_mountp->m_sb) &&
	    ip->i_d.di_version == XFS_DINODE_VERSION_1) {
		ip->i_d.di_version = XFS_DINODE_VERSION_2;
		/*
		 * We've already zeroed the old link count, the projid field,
		 * and the pad field.
		 */
	}

	/*
	 * Project ids won't be stored on disk if we are using a version 1 inode.
	 */
	if ( (prid != 0) && (ip->i_d.di_version == XFS_DINODE_VERSION_1))
		xfs_bump_ino_vers2(tp, ip);

	if (XFS_INHERIT_GID(pip, vp->v_vfsp)) {
		ip->i_d.di_gid = pip->i_d.di_gid;
		if ((pip->i_d.di_mode & S_ISGID) && (mode & S_IFMT) == S_IFDIR) {
			ip->i_d.di_mode |= S_ISGID;
		}
	}

	/*
	 * If the group ID of the new file does not match the effective group
	 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
	 * (and only if the irix_sgid_inherit compatibility variable is set).
	 */
	if ((irix_sgid_inherit) &&
	    (ip->i_d.di_mode & S_ISGID) &&
	    (!groupmember((gid_t)ip->i_d.di_gid, curthread->td_ucred))) {
		ip->i_d.di_mode &= ~S_ISGID;
	}

	ip->i_d.di_size = 0;
	ip->i_d.di_nextents = 0;
	ASSERT(ip->i_d.di_nblocks == 0);
	xfs_ichgtime(ip, XFS_ICHGTIME_CHG|XFS_ICHGTIME_ACC|XFS_ICHGTIME_MOD);
	/*
	 * di_gen will have been taken care of in xfs_iread.
	 */
	ip->i_d.di_extsize = 0;
	ip->i_d.di_dmevmask = 0;
	ip->i_d.di_dmstate = 0;
	ip->i_d.di_flags = 0;
	flags = XFS_ILOG_CORE;
	switch (mode & S_IFMT) {
	case S_IFIFO:
	case S_IFCHR:
	case S_IFBLK:
	case S_IFSOCK:
		ip->i_d.di_format = XFS_DINODE_FMT_DEV;
		ip->i_df.if_u2.if_rdev = rdev;
		ip->i_df.if_flags = 0;
		flags |= XFS_ILOG_DEV;
		break;
	case S_IFREG:
	case S_IFDIR:
		if (pip->i_d.di_flags &
		    (XFS_DIFLAG_NOATIME|XFS_DIFLAG_NODUMP|XFS_DIFLAG_SYNC)) {
			if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
			    xfs_inherit_noatime)
				ip->i_d.di_flags |= XFS_DIFLAG_NOATIME;
			if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
			    xfs_inherit_nodump)
				ip->i_d.di_flags |= XFS_DIFLAG_NODUMP;
			if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
			    xfs_inherit_sync)
				ip->i_d.di_flags |= XFS_DIFLAG_SYNC;
		}
	case S_IFLNK:
		ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
		ip->i_df.if_flags = XFS_IFEXTENTS;
		ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
		ip->i_df.if_u1.if_extents = NULL;
		break;
	default:
		ASSERT(0);
	}
	/*
	 * Attribute fork settings for new inode.
	 */
	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
	ip->i_d.di_anextents = 0;

	/*
	 * Log the new values stuffed into the inode.
	 */
	xfs_trans_log_inode(tp, ip, flags);

	/* now that we have a v_type we can set Linux inode ops (& unlock) */
	XVFS_INIT_VNODE(XFS_MTOVFS(tp->t_mountp), vp, XFS_ITOBHV(ip), 1);

	*ipp = ip;
	return 0;
}

/*
 * Check to make sure that there are no blocks allocated to the
 * file beyond the size of the file.  We don't check this for
 * files with fixed size extents or real time extents, but we
 * at least do it for regular files.
 */
#ifdef DEBUG
void
xfs_isize_check(
	xfs_mount_t	*mp,
	xfs_inode_t	*ip,
	xfs_fsize_t	isize)
{
	xfs_fileoff_t	map_first;
	int		nimaps;
	xfs_bmbt_irec_t	imaps[2];

	if ((ip->i_d.di_mode & S_IFMT) != S_IFREG)
		return;

	if ( ip->i_d.di_flags & XFS_DIFLAG_REALTIME )
		return;

	nimaps = 2;
	map_first = XFS_B_TO_FSB(mp, (xfs_ufsize_t)isize);
	/*
	 * The filesystem could be shutting down, so bmapi may return
	 * an error.
	 */
	if (xfs_bmapi(NULL, ip, map_first,
			 (XFS_B_TO_FSB(mp,
				       (xfs_ufsize_t)XFS_MAXIOFFSET(mp)) -
			  map_first),
			 XFS_BMAPI_ENTIRE, NULL, 0, imaps, &nimaps,
			 NULL))
	    return;
	ASSERT(nimaps == 1);
	ASSERT(imaps[0].br_startblock == HOLESTARTBLOCK);
}
#endif	/* DEBUG */

/*
 * Calculate the last possible buffered byte in a file.  This must
 * include data that was buffered beyond the EOF by the write code.
 * This also needs to deal with overflowing the xfs_fsize_t type
 * which can happen for sizes near the limit.
 *
 * We also need to take into account any blocks beyond the EOF.  It
 * may be the case that they were buffered by a write which failed.
 * In that case the pages will still be in memory, but the inode size
 * will never have been updated.
 */
xfs_fsize_t
xfs_file_last_byte(
	xfs_inode_t	*ip)
{
	xfs_mount_t	*mp;
	xfs_fsize_t	last_byte;
	xfs_fileoff_t	last_block;
	xfs_fileoff_t	size_last_block;
	int		error;

	ASSERT(ismrlocked(&(ip->i_iolock), MR_UPDATE | MR_ACCESS));

	mp = ip->i_mount;
	/*
	 * Only check for blocks beyond the EOF if the extents have
	 * been read in.  This eliminates the need for the inode lock,
	 * and it also saves us from looking when it really isn't
	 * necessary.
	 */
	if (ip->i_df.if_flags & XFS_IFEXTENTS) {
		error = xfs_bmap_last_offset(NULL, ip, &last_block,
			XFS_DATA_FORK);
		if (error) {
			last_block = 0;
		}
	} else {
		last_block = 0;
	}
	size_last_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)ip->i_d.di_size);
	last_block = XFS_FILEOFF_MAX(last_block, size_last_block);

	last_byte = XFS_FSB_TO_B(mp, last_block);
	if (last_byte < 0) {
		return XFS_MAXIOFFSET(mp);
	}
	last_byte += (1 << mp->m_writeio_log);
	if (last_byte < 0) {
		return XFS_MAXIOFFSET(mp);
	}
	return last_byte;
}

#if defined(XFS_RW_TRACE)
STATIC void
xfs_itrunc_trace(
	int		tag,
	xfs_inode_t	*ip,
	int		flag,
	xfs_fsize_t	new_size,
	xfs_off_t	toss_start,
	xfs_off_t	toss_finish)
{
	if (ip->i_rwtrace == NULL) {
		return;
	}

	ktrace_enter(ip->i_rwtrace,
		     (void*)((long)tag),
		     (void*)ip,
		     (void*)(unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff),
		     (void*)(unsigned long)(ip->i_d.di_size & 0xffffffff),
		     (void*)((long)flag),
		     (void*)(unsigned long)((new_size >> 32) & 0xffffffff),
		     (void*)(unsigned long)(new_size & 0xffffffff),
		     (void*)(unsigned long)((toss_start >> 32) & 0xffffffff),
		     (void*)(unsigned long)(toss_start & 0xffffffff),
		     (void*)(unsigned long)((toss_finish >> 32) & 0xffffffff),
		     (void*)(unsigned long)(toss_finish & 0xffffffff),
		     (void*)(unsigned long)current_cpu(),
		     (void*)0,
		     (void*)0,
		     (void*)0,
		     (void*)0);
}
#else
#define	xfs_itrunc_trace(tag, ip, flag, new_size, toss_start, toss_finish)
#endif

/*
 * Start the truncation of the file to new_size.  The new size
 * must be smaller than the current size.  This routine will
 * clear the buffer and page caches of file data in the removed
 * range, and xfs_itruncate_finish() will remove the underlying
 * disk blocks.
 *
 * The inode must have its I/O lock locked EXCLUSIVELY, and it
 * must NOT have the inode lock held at all.  This is because we're
 * calling into the buffer/page cache code and we can't hold the
 * inode lock when we do so.
 *
 * The flags parameter can have either the value XFS_ITRUNC_DEFINITE
 * or XFS_ITRUNC_MAYBE.  The XFS_ITRUNC_MAYBE value should be used
 * in the case that the caller is locking things out of order and
 * may not be able to call xfs_itruncate_finish() with the inode lock
 * held without dropping the I/O lock.  If the caller must drop the
 * I/O lock before calling xfs_itruncate_finish(), then xfs_itruncate_start()
 * must be called again with all the same restrictions as the initial
 * call.
 */
void
xfs_itruncate_start(
	xfs_inode_t	*ip,
	uint		flags,
	xfs_fsize_t	new_size)
{
	xfs_fsize_t	last_byte;
	xfs_off_t	toss_start;
	xfs_mount_t	*mp;
	xfs_vnode_t	*vp;

	ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE) != 0);
	ASSERT((new_size == 0) || (new_size <= ip->i_d.di_size));
	ASSERT((flags == XFS_ITRUNC_DEFINITE) ||
	       (flags == XFS_ITRUNC_MAYBE));

	mp = ip->i_mount;
	vp = XFS_ITOV(ip);
	/*
	 * Call VOP_TOSS_PAGES() or VOP_FLUSHINVAL_PAGES() to get rid of pages and buffers
	 * overlapping the region being removed.  We have to use
	 * the less efficient VOP_FLUSHINVAL_PAGES() in the case that the
	 * caller may not be able to finish the truncate without
	 * dropping the inode's I/O lock.  Make sure
	 * to catch any pages brought in by buffers overlapping
	 * the EOF by searching out beyond the isize by our
	 * block size. We round new_size up to a block boundary
	 * so that we don't toss things on the same block as
	 * new_size but before it.
	 *
	 * Before calling VOP_TOSS_PAGES() or VOP_FLUSHINVAL_PAGES(), make sure to
	 * call remapf() over the same region if the file is mapped.
	 * This frees up mapped file references to the pages in the
	 * given range and for the VOP_FLUSHINVAL_PAGES() case it ensures
	 * that we get the latest mapped changes flushed out.
	 */
	toss_start = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
	toss_start = XFS_FSB_TO_B(mp, toss_start);
	if (toss_start < 0) {
		/*
		 * The place to start tossing is beyond our maximum
		 * file size, so there is no way that the data extended
		 * out there.
		 */
		return;
	}
	last_byte = xfs_file_last_byte(ip);
	xfs_itrunc_trace(XFS_ITRUNC_START, ip, flags, new_size, toss_start,
			 last_byte);
	if (last_byte > toss_start) {
		if (flags & XFS_ITRUNC_DEFINITE) {
			XVOP_TOSS_PAGES(vp, toss_start, -1, FI_REMAPF_LOCKED);
		} else {
			XVOP_FLUSHINVAL_PAGES(vp, toss_start, -1, FI_REMAPF_LOCKED);
		}
	}

#ifdef DEBUG
	if (new_size == 0) {
		ASSERT(VN_CACHED(vp) == 0);
	}
#endif
}

/*
 * Shrink the file to the given new_size.  The new
 * size must be smaller than the current size.
 * This will free up the underlying blocks
 * in the removed range after a call to xfs_itruncate_start()
 * or xfs_atruncate_start().
 *
 * The transaction passed to this routine must have made
 * a permanent log reservation of at least XFS_ITRUNCATE_LOG_RES.
 * This routine may commit the given transaction and
 * start new ones, so make sure everything involved in
 * the transaction is tidy before calling here.
 * Some transaction will be returned to the caller to be
 * committed.  The incoming transaction must already include
 * the inode, and both inode locks must be held exclusively.
 * The inode must also be "held" within the transaction.  On
 * return the inode will be "held" within the returned transaction.
 * This routine does NOT require any disk space to be reserved
 * for it within the transaction.
 *
 * The fork parameter must be either xfs_attr_fork or xfs_data_fork,
 * and it indicates the fork which is to be truncated.  For the
 * attribute fork we only support truncation to size 0.
 *
 * We use the sync parameter to indicate whether or not the first
 * transaction we perform might have to be synchronous.  For the attr fork,
 * it needs to be so if the unlink of the inode is not yet known to be
 * permanent in the log.  This keeps us from freeing and reusing the
 * blocks of the attribute fork before the unlink of the inode becomes
 * permanent.
 *
 * For the data fork, we normally have to run synchronously if we're
 * being called out of the inactive path or we're being called
 * out of the create path where we're truncating an existing file.
 * Either way, the truncate needs to be sync so blocks don't reappear
 * in the file with altered data in case of a crash.  wsync filesystems
 * can run the first case async because anything that shrinks the inode
 * has to run sync so by the time we're called here from inactive, the
 * inode size is permanently set to 0.
 *
 * Calls from the truncate path always need to be sync unless we're
 * in a wsync filesystem and the file has already been unlinked.
 *
 * The caller is responsible for correctly setting the sync parameter.
 * It gets too hard for us to guess here which path we're being called
 * out of just based on inode state.
 */
int
xfs_itruncate_finish(
	xfs_trans_t	**tp,
	xfs_inode_t	*ip,
	xfs_fsize_t	new_size,
	int		fork,
	int		sync)
{
	xfs_fsblock_t	first_block;
	xfs_fileoff_t	first_unmap_block;
	xfs_fileoff_t	last_block;
	xfs_filblks_t	unmap_len=0;
	xfs_mount_t	*mp;
	xfs_trans_t	*ntp;
	int		done;
	int		committed;
	xfs_bmap_free_t	free_list;
	int		error;

	ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE) != 0);
	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE) != 0);
	ASSERT((new_size == 0) || (new_size <= ip->i_d.di_size));
	ASSERT(*tp != NULL);
	ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES);
	ASSERT(ip->i_transp == *tp);
	ASSERT(ip->i_itemp != NULL);
	ASSERT(ip->i_itemp->ili_flags & XFS_ILI_HOLD);


	ntp = *tp;
	mp = (ntp)->t_mountp;
	ASSERT(! XFS_NOT_DQATTACHED(mp, ip));

	/*
	 * We only support truncating the entire attribute fork.
	 */
	if (fork == XFS_ATTR_FORK) {
		new_size = 0LL;
	}
	first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
	xfs_itrunc_trace(XFS_ITRUNC_FINISH1, ip, 0, new_size, 0, 0);
	/*
	 * The first thing we do is set the size to new_size permanently
	 * on disk.  This way we don't have to worry about anyone ever
	 * being able to look at the data being freed even in the face
	 * of a crash.  What we're getting around here is the case where
	 * we free a block, it is allocated to another file, it is written
	 * to, and then we crash.  If the new data gets written to the
	 * file but the log buffers containing the free and reallocation
	 * don't, then we'd end up with garbage in the blocks being freed.
	 * As long as we make the new_size permanent before actually
	 * freeing any blocks it doesn't matter if they get writtten to.
	 *
	 * The callers must signal into us whether or not the size
	 * setting here must be synchronous.  There are a few cases
	 * where it doesn't have to be synchronous.  Those cases
	 * occur if the file is unlinked and we know the unlink is
	 * permanent or if the blocks being truncated are guaranteed
	 * to be beyond the inode eof (regardless of the link count)
	 * and the eof value is permanent.  Both of these cases occur
	 * only on wsync-mounted filesystems.  In those cases, we're
	 * guaranteed that no user will ever see the data in the blocks
	 * that are being truncated so the truncate can run async.
	 * In the free beyond eof case, the file may wind up with
	 * more blocks allocated to it than it needs if we crash
	 * and that won't get fixed until the next time the file
	 * is re-opened and closed but that's ok as that shouldn't
	 * be too many blocks.
	 *
	 * However, we can't just make all wsync xactions run async
	 * because there's one call out of the create path that needs
	 * to run sync where it's truncating an existing file to size
	 * 0 whose size is > 0.
	 *
	 * It's probably possible to come up with a test in this
	 * routine that would correctly distinguish all the above
	 * cases from the values of the function parameters and the
	 * inode state but for sanity's sake, I've decided to let the
	 * layers above just tell us.  It's simpler to correctly figure
	 * out in the layer above exactly under what conditions we
	 * can run async and I think it's easier for others read and
	 * follow the logic in case something has to be changed.
	 * cscope is your friend -- rcc.
	 *
	 * The attribute fork is much simpler.
	 *
	 * For the attribute fork we allow the caller to tell us whether
	 * the unlink of the inode that led to this call is yet permanent
	 * in the on disk log.  If it is not and we will be freeing extents
	 * in this inode then we make the first transaction synchronous
	 * to make sure that the unlink is permanent by the time we free
	 * the blocks.
	 */
	if (fork == XFS_DATA_FORK) {
		if (ip->i_d.di_nextents > 0) {
			ip->i_d.di_size = new_size;
			xfs_trans_log_inode(ntp, ip, XFS_ILOG_CORE);
		}
	} else if (sync) {
		ASSERT(!(mp->m_flags & XFS_MOUNT_WSYNC));
		if (ip->i_d.di_anextents > 0)
			xfs_trans_set_sync(ntp);
	}
	ASSERT(fork == XFS_DATA_FORK ||
		(fork == XFS_ATTR_FORK &&
			((sync && !(mp->m_flags & XFS_MOUNT_WSYNC)) ||
			 (sync == 0 && (mp->m_flags & XFS_MOUNT_WSYNC)))));

	/*
	 * Since it is possible for space to become allocated beyond
	 * the end of the file (in a crash where the space is allocated
	 * but the inode size is not yet updated), simply remove any
	 * blocks which show up between the new EOF and the maximum
	 * possible file size.  If the first block to be removed is
	 * beyond the maximum file size (ie it is the same as last_block),
	 * then there is nothing to do.
	 */
	last_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
	ASSERT(first_unmap_block <= last_block);
	done = 0;
	if (last_block == first_unmap_block) {
		done = 1;
	} else {
		unmap_len = last_block - first_unmap_block + 1;
	}
	while (!done) {
		/*
		 * Free up up to XFS_ITRUNC_MAX_EXTENTS.  xfs_bunmapi()
		 * will tell us whether it freed the entire range or
		 * not.  If this is a synchronous mount (wsync),
		 * then we can tell bunmapi to keep all the
		 * transactions asynchronous since the unlink
		 * transaction that made this inode inactive has
		 * already hit the disk.  There's no danger of
		 * the freed blocks being reused, there being a
		 * crash, and the reused blocks suddenly reappearing
		 * in this file with garbage in them once recovery
		 * runs.
		 */
		XFS_BMAP_INIT(&free_list, &first_block);
		error = xfs_bunmapi(ntp, ip, first_unmap_block,
				    unmap_len,
				    XFS_BMAPI_AFLAG(fork) |
				      (sync ? 0 : XFS_BMAPI_ASYNC),
				    XFS_ITRUNC_MAX_EXTENTS,
				    &first_block, &free_list, &done);
		if (error) {
			/*
			 * If the bunmapi call encounters an error,
			 * return to the caller where the transaction
			 * can be properly aborted.  We just need to
			 * make sure we're not holding any resources
			 * that we were not when we came in.
			 */
			xfs_bmap_cancel(&free_list);
			return error;
		}

		/*
		 * Duplicate the transaction that has the permanent
		 * reservation and commit the old transaction.
		 */
		error = xfs_bmap_finish(tp, &free_list, first_block,
					&committed);
		ntp = *tp;
		if (error) {
			/*
			 * If the bmap finish call encounters an error,
			 * return to the caller where the transaction
			 * can be properly aborted.  We just need to
			 * make sure we're not holding any resources
			 * that we were not when we came in.
			 *
			 * Aborting from this point might lose some
			 * blocks in the file system, but oh well.
			 */
			xfs_bmap_cancel(&free_list);
			if (committed) {
				/*
				 * If the passed in transaction committed
				 * in xfs_bmap_finish(), then we want to
				 * add the inode to this one before returning.
				 * This keeps things simple for the higher
				 * level code, because it always knows that
				 * the inode is locked and held in the
				 * transaction that returns to it whether
				 * errors occur or not.  We don't mark the
				 * inode dirty so that this transaction can
				 * be easily aborted if possible.
				 */
				xfs_trans_ijoin(ntp, ip,
					XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
				xfs_trans_ihold(ntp, ip);
			}
			return error;
		}

		if (committed) {
			/*
			 * The first xact was committed,
			 * so add the inode to the new one.
			 * Mark it dirty so it will be logged
			 * and moved forward in the log as
			 * part of every commit.
			 */
			xfs_trans_ijoin(ntp, ip,
					XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
			xfs_trans_ihold(ntp, ip);
			xfs_trans_log_inode(ntp, ip, XFS_ILOG_CORE);
		}
		ntp = xfs_trans_dup(ntp);
		(void) xfs_trans_commit(*tp, 0, NULL);
		*tp = ntp;
		error = xfs_trans_reserve(ntp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0,
					  XFS_TRANS_PERM_LOG_RES,
					  XFS_ITRUNCATE_LOG_COUNT);
		/*
		 * Add the inode being truncated to the next chained
		 * transaction.
		 */
		xfs_trans_ijoin(ntp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL);
		xfs_trans_ihold(ntp, ip);
		if (error)
			return (error);
	}
	/*
	 * Only update the size in the case of the data fork, but
	 * always re-log the inode so that our permanent transaction
	 * can keep on rolling it forward in the log.
	 */
	if (fork == XFS_DATA_FORK) {
		xfs_isize_check(mp, ip, new_size);
		ip->i_d.di_size = new_size;
	}
	xfs_trans_log_inode(ntp, ip, XFS_ILOG_CORE);
	ASSERT((new_size != 0) ||
	       (fork == XFS_ATTR_FORK) ||
	       (ip->i_delayed_blks == 0));
	ASSERT((new_size != 0) ||
	       (fork == XFS_ATTR_FORK) ||
	       (ip->i_d.di_nextents == 0));
	xfs_itrunc_trace(XFS_ITRUNC_FINISH2, ip, 0, new_size, 0, 0);
	return 0;
}


/*
 * xfs_igrow_start
 *
 * Do the first part of growing a file: zero any data in the last
 * block that is beyond the old EOF.  We need to do this before
 * the inode is joined to the transaction to modify the i_size.
 * That way we can drop the inode lock and call into the buffer
 * cache to get the buffer mapping the EOF.
 */
int
xfs_igrow_start(
	xfs_inode_t	*ip,
	xfs_fsize_t	new_size,
	cred_t		*credp)
{
	xfs_fsize_t	isize;
	int		error;

	ASSERT(ismrlocked(&(ip->i_lock), MR_UPDATE) != 0);
	ASSERT(ismrlocked(&(ip->i_iolock), MR_UPDATE) != 0);
	ASSERT(new_size > ip->i_d.di_size);

	error = 0;
	isize = ip->i_d.di_size;
	/*
	 * Zero any pages that may have been created by
	 * xfs_write_file() beyond the end of the file
	 * and any blocks between the old and new file sizes.
	 */
	error = xfs_zero_eof(XFS_ITOV(ip), &ip->i_iocore, new_size, isize,
				new_size);
	return error;
}

/*
 * xfs_igrow_finish
 *
 * This routine is called to extend the size of a file.
 * The inode must have both the iolock and the ilock locked
 * for update and it must be a part of the current transaction.
 * The xfs_igrow_start() function must have been called previously.
 * If the change_flag is not zero, the inode change timestamp will
 * be updated.
 */
void
xfs_igrow_finish(
	xfs_trans_t	*tp,
	xfs_inode_t	*ip,
	xfs_fsize_t	new_size,
	int		change_flag)
{
	ASSERT(ismrlocked(&(ip->i_lock), MR_UPDATE) != 0);
	ASSERT(ismrlocked(&(ip->i_iolock), MR_UPDATE) != 0);
	ASSERT(ip->i_transp == tp);
	ASSERT(new_size > ip->i_d.di_size);

	/*
	 * Update the file size.  Update the inode change timestamp
	 * if change_flag set.
	 */
	ip->i_d.di_size = new_size;
	if (change_flag)
		xfs_ichgtime(ip, XFS_ICHGTIME_CHG);
	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);

}


/*
 * This is called when the inode's link count goes to 0.
 * We place the on-disk inode on a list in the AGI.  It
 * will be pulled from this list when the inode is freed.
 */
int
xfs_iunlink(
	xfs_trans_t	*tp,
	xfs_inode_t	*ip)
{
	xfs_mount_t	*mp;
	xfs_agi_t	*agi;
	xfs_dinode_t	*dip;
	xfs_buf_t	*agibp;
	xfs_buf_t	*ibp;
	xfs_agnumber_t	agno;
	xfs_daddr_t	agdaddr;
	xfs_agino_t	agino;
	short		bucket_index;
	int		offset;
	int		error;
	int		agi_ok;

	ASSERT(ip->i_d.di_nlink == 0);
	ASSERT(ip->i_d.di_mode != 0);
	ASSERT(ip->i_transp == tp);

	mp = tp->t_mountp;

	agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
	agdaddr = XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp));

	/*
	 * Get the agi buffer first.  It ensures lock ordering
	 * on the list.
	 */
	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, agdaddr,
				   XFS_FSS_TO_BB(mp, 1), 0, &agibp);
	if (error) {
		return error;
	}
	/*
	 * Validate the magic number of the agi block.
	 */
	agi = XFS_BUF_TO_AGI(agibp);
	agi_ok =
		INT_GET(agi->agi_magicnum, ARCH_CONVERT) == XFS_AGI_MAGIC &&
		XFS_AGI_GOOD_VERSION(INT_GET(agi->agi_versionnum, ARCH_CONVERT));
	if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IUNLINK,
			XFS_RANDOM_IUNLINK))) {
		XFS_CORRUPTION_ERROR("xfs_iunlink", XFS_ERRLEVEL_LOW, mp, agi);
		xfs_trans_brelse(tp, agibp);
		return XFS_ERROR(EFSCORRUPTED);
	}
	/*
	 * Get the index into the agi hash table for the
	 * list this inode will go on.
	 */
	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
	ASSERT(agino != 0);
	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
	ASSERT(!INT_ISZERO(agi->agi_unlinked[bucket_index], ARCH_CONVERT));
	ASSERT(INT_GET(agi->agi_unlinked[bucket_index], ARCH_CONVERT) != agino);

	if (INT_GET(agi->agi_unlinked[bucket_index], ARCH_CONVERT) != NULLAGINO) {
		/*
		 * There is already another inode in the bucket we need
		 * to add ourselves to.  Add us at the front of the list.
		 * Here we put the head pointer into our next pointer,
		 * and then we fall through to point the head at us.
		 */
		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
		if (error) {
			return error;
		}
		ASSERT(INT_GET(dip->di_next_unlinked, ARCH_CONVERT) == NULLAGINO);
		ASSERT(!INT_ISZERO(dip->di_next_unlinked, ARCH_CONVERT));
		/* both on-disk, don't endian flip twice */
		dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
		offset = ip->i_boffset +
			offsetof(xfs_dinode_t, di_next_unlinked);
		xfs_trans_inode_buf(tp, ibp);
		xfs_trans_log_buf(tp, ibp, offset,
				  (offset + sizeof(xfs_agino_t) - 1));
		xfs_inobp_check(mp, ibp);
	}

	/*
	 * Point the bucket head pointer at the inode being inserted.
	 */
	ASSERT(agino != 0);
	INT_SET(agi->agi_unlinked[bucket_index], ARCH_CONVERT, agino);
	offset = offsetof(xfs_agi_t, agi_unlinked) +
		(sizeof(xfs_agino_t) * bucket_index);
	xfs_trans_log_buf(tp, agibp, offset,
			  (offset + sizeof(xfs_agino_t) - 1));
	return 0;
}

/*
 * Pull the on-disk inode from the AGI unlinked list.
 */
STATIC int
xfs_iunlink_remove(
	xfs_trans_t	*tp,
	xfs_inode_t	*ip)
{
	xfs_ino_t	next_ino;
	xfs_mount_t	*mp;
	xfs_agi_t	*agi;
	xfs_dinode_t	*dip;
	xfs_buf_t	*agibp;
	xfs_buf_t	*ibp;
	xfs_agnumber_t	agno;
	xfs_daddr_t	agdaddr;
	xfs_agino_t	agino;
	xfs_agino_t	next_agino;
	xfs_buf_t	*last_ibp;
	xfs_dinode_t	*last_dip;
	short		bucket_index;
	int		offset, last_offset;
	int		error;
	int		agi_ok;

	/*
	 * First pull the on-disk inode from the AGI unlinked list.
	 */
	mp = tp->t_mountp;

	agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
	agdaddr = XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp));

	/*
	 * Get the agi buffer first.  It ensures lock ordering
	 * on the list.
	 */
	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, agdaddr,
				   XFS_FSS_TO_BB(mp, 1), 0, &agibp);
	if (error) {
		cmn_err(CE_WARN,
			"xfs_iunlink_remove: xfs_trans_read_buf()  returned an error %d on %s.  Returning error.",
			error, mp->m_fsname);
		return error;
	}
	/*
	 * Validate the magic number of the agi block.
	 */
	agi = XFS_BUF_TO_AGI(agibp);
	agi_ok =
		INT_GET(agi->agi_magicnum, ARCH_CONVERT) == XFS_AGI_MAGIC &&
		XFS_AGI_GOOD_VERSION(INT_GET(agi->agi_versionnum, ARCH_CONVERT));
	if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IUNLINK_REMOVE,
			XFS_RANDOM_IUNLINK_REMOVE))) {
		XFS_CORRUPTION_ERROR("xfs_iunlink_remove", XFS_ERRLEVEL_LOW,
				     mp, agi);
		xfs_trans_brelse(tp, agibp);
		cmn_err(CE_WARN,
			"xfs_iunlink_remove: XFS_TEST_ERROR()  returned an error on %s.  Returning EFSCORRUPTED.",
			 mp->m_fsname);
		return XFS_ERROR(EFSCORRUPTED);
	}
	/*
	 * Get the index into the agi hash table for the
	 * list this inode will go on.
	 */
	agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
	ASSERT(agino != 0);
	bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
	ASSERT(INT_GET(agi->agi_unlinked[bucket_index], ARCH_CONVERT) != NULLAGINO);
	ASSERT(!INT_ISZERO(agi->agi_unlinked[bucket_index], ARCH_CONVERT));

	if (INT_GET(agi->agi_unlinked[bucket_index], ARCH_CONVERT) == agino) {
		/*
		 * We're at the head of the list.  Get the inode's
		 * on-disk buffer to see if there is anyone after us
		 * on the list.  Only modify our next pointer if it
		 * is not already NULLAGINO.  This saves us the overhead
		 * of dealing with the buffer when there is no need to
		 * change it.
		 */
		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
		if (error) {
			cmn_err(CE_WARN,
				"xfs_iunlink_remove: xfs_itobp()  returned an error %d on %s.  Returning error.",
				error, mp->m_fsname);
			return error;
		}
		next_agino = INT_GET(dip->di_next_unlinked, ARCH_CONVERT);
		ASSERT(next_agino != 0);
		if (next_agino != NULLAGINO) {
			INT_SET(dip->di_next_unlinked, ARCH_CONVERT, NULLAGINO);
			offset = ip->i_boffset +
				offsetof(xfs_dinode_t, di_next_unlinked);
			xfs_trans_inode_buf(tp, ibp);
			xfs_trans_log_buf(tp, ibp, offset,
					  (offset + sizeof(xfs_agino_t) - 1));
			xfs_inobp_check(mp, ibp);
		} else {
			xfs_trans_brelse(tp, ibp);
		}
		/*
		 * Point the bucket head pointer at the next inode.
		 */
		ASSERT(next_agino != 0);
		ASSERT(next_agino != agino);
		INT_SET(agi->agi_unlinked[bucket_index], ARCH_CONVERT, next_agino);
		offset = offsetof(xfs_agi_t, agi_unlinked) +
			(sizeof(xfs_agino_t) * bucket_index);
		xfs_trans_log_buf(tp, agibp, offset,
				  (offset + sizeof(xfs_agino_t) - 1));
	} else {
		/*
		 * We need to search the list for the inode being freed.
		 */
		next_agino = INT_GET(agi->agi_unlinked[bucket_index], ARCH_CONVERT);
		last_ibp = NULL;
		while (next_agino != agino) {
			/*
			 * If the last inode wasn't the one pointing to
			 * us, then release its buffer since we're not
			 * going to do anything with it.
			 */
			if (last_ibp != NULL) {
				xfs_trans_brelse(tp, last_ibp);
			}
			next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
			error = xfs_inotobp(mp, tp, next_ino, &last_dip,
					    &last_ibp, &last_offset);
			if (error) {
				cmn_err(CE_WARN,
			"xfs_iunlink_remove: xfs_inotobp()  returned an error %d on %s.  Returning error.",
					error, mp->m_fsname);
				return error;
			}
			next_agino = INT_GET(last_dip->di_next_unlinked, ARCH_CONVERT);
			ASSERT(next_agino != NULLAGINO);
			ASSERT(next_agino != 0);
		}
		/*
		 * Now last_ibp points to the buffer previous to us on
		 * the unlinked list.  Pull us from the list.
		 */
		error = xfs_itobp(mp, tp, ip, &dip, &ibp, 0);
		if (error) {
			cmn_err(CE_WARN,
				"xfs_iunlink_remove: xfs_itobp()  returned an error %d on %s.  Returning error.",
				error, mp->m_fsname);
			return error;
		}
		next_agino = INT_GET(dip->di_next_unlinked, ARCH_CONVERT);
		ASSERT(next_agino != 0);
		ASSERT(next_agino != agino);
		if (next_agino != NULLAGINO) {
			INT_SET(dip->di_next_unlinked, ARCH_CONVERT, NULLAGINO);
			offset = ip->i_boffset +
				offsetof(xfs_dinode_t, di_next_unlinked);
			xfs_trans_inode_buf(tp, ibp);
			xfs_trans_log_buf(tp, ibp, offset,
					  (offset + sizeof(xfs_agino_t) - 1));
			xfs_inobp_check(mp, ibp);
		} else {
			xfs_trans_brelse(tp, ibp);
		}
		/*
		 * Point the previous inode on the list to the next inode.
		 */
		INT_SET(last_dip->di_next_unlinked, ARCH_CONVERT, next_agino);
		ASSERT(next_agino != 0);
		offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
		xfs_trans_inode_buf(tp, last_ibp);
		xfs_trans_log_buf(tp, last_ibp, offset,
				  (offset + sizeof(xfs_agino_t) - 1));
		xfs_inobp_check(mp, last_ibp);
	}
	return 0;
}

static __inline__ int xfs_inode_clean(xfs_inode_t *ip)
{
	return (((ip->i_itemp == NULL) ||
		!(ip->i_itemp->ili_format.ilf_fields & XFS_ILOG_ALL)) &&
		(ip->i_update_core == 0));
}

STATIC void
xfs_ifree_cluster(
	xfs_inode_t	*free_ip,
	xfs_trans_t	*tp,
	xfs_ino_t	inum)
{
	xfs_mount_t		*mp = free_ip->i_mount;
	int			blks_per_cluster;
	int			nbufs;
	int			ninodes;
	int			i, j, found, pre_flushed;
	xfs_daddr_t		blkno;
	xfs_buf_t		*bp;
	xfs_ihash_t		*ih;
	xfs_inode_t		*ip, **ip_found;
	xfs_inode_log_item_t	*iip;
	xfs_log_item_t		*lip;
	SPLDECL(s);

	if (mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) {
		blks_per_cluster = 1;
		ninodes = mp->m_sb.sb_inopblock;
		nbufs = XFS_IALLOC_BLOCKS(mp);
	} else {
		blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) /
					mp->m_sb.sb_blocksize;
		ninodes = blks_per_cluster * mp->m_sb.sb_inopblock;
		nbufs = XFS_IALLOC_BLOCKS(mp) / blks_per_cluster;
	}

	ip_found = kmem_alloc(ninodes * sizeof(xfs_inode_t *), KM_NOFS);

	for (j = 0; j < nbufs; j++, inum += ninodes) {
		blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
					 XFS_INO_TO_AGBNO(mp, inum));


		/*
		 * Look for each inode in memory and attempt to lock it,
		 * we can be racing with flush and tail pushing here.
		 * any inode we get the locks on, add to an array of
		 * inode items to process later.
		 *
		 * The get the buffer lock, we could beat a flush
		 * or tail pushing thread to the lock here, in which
		 * case they will go looking for the inode buffer
		 * and fail, we need some other form of interlock
		 * here.
		 */
		found = 0;
		for (i = 0; i < ninodes; i++) {
			ih = XFS_IHASH(mp, inum + i);
			read_lock(&ih->ih_lock);
			for (ip = ih->ih_next; ip != NULL; ip = ip->i_next) {
				if (ip->i_ino == inum + i)
					break;
			}

			/* Inode not in memory or we found it already,
			 * nothing to do
			 */
			if (!ip || (ip->i_flags & XFS_ISTALE)) {
				read_unlock(&ih->ih_lock);
				continue;
			}

			if (xfs_inode_clean(ip)) {
				read_unlock(&ih->ih_lock);
				continue;
			}

			/* If we can get the locks then add it to the
			 * list, otherwise by the time we get the bp lock
			 * below it will already be attached to the
			 * inode buffer.
			 */

			/* This inode will already be locked - by us, lets
			 * keep it that way.
			 */

			if (ip == free_ip) {
				if (xfs_iflock_nowait(ip)) {
					ip->i_flags |= XFS_ISTALE;

					if (xfs_inode_clean(ip)) {
						xfs_ifunlock(ip);
					} else {
						ip_found[found++] = ip;
					}
				}
				read_unlock(&ih->ih_lock);
				continue;
			}

			if (xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
				if (xfs_iflock_nowait(ip)) {
					ip->i_flags |= XFS_ISTALE;

					if (xfs_inode_clean(ip)) {
						xfs_ifunlock(ip);
						xfs_iunlock(ip, XFS_ILOCK_EXCL);
					} else {
						ip_found[found++] = ip;
					}
				} else {
					xfs_iunlock(ip, XFS_ILOCK_EXCL);
				}
			}

			read_unlock(&ih->ih_lock);
		}

		bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
					mp->m_bsize * blks_per_cluster,
					XFS_BUF_LOCK);

		pre_flushed = 0;
		lip = XFS_BUF_FSPRIVATE(bp, xfs_log_item_t *);
		while (lip) {
			if (lip->li_type == XFS_LI_INODE) {
				iip = (xfs_inode_log_item_t *)lip;
				ASSERT(iip->ili_logged == 1);
				lip->li_cb = (void(*)(xfs_buf_t*,xfs_log_item_t*)) xfs_istale_done;
				AIL_LOCK(mp,s);
				iip->ili_flush_lsn = iip->ili_item.li_lsn;
				AIL_UNLOCK(mp, s);
				iip->ili_inode->i_flags |= XFS_ISTALE;
				pre_flushed++;
			}
			lip = lip->li_bio_list;
		}

		for (i = 0; i < found; i++) {
			ip = ip_found[i];
			iip = ip->i_itemp;

			if (!iip) {
				ip->i_update_core = 0;
				xfs_ifunlock(ip);
				xfs_iunlock(ip, XFS_ILOCK_EXCL);
				continue;
			}

			iip->ili_last_fields = iip->ili_format.ilf_fields;
			iip->ili_format.ilf_fields = 0;
			iip->ili_logged = 1;
			AIL_LOCK(mp,s);
			iip->ili_flush_lsn = iip->ili_item.li_lsn;
			AIL_UNLOCK(mp, s);

			xfs_buf_attach_iodone(bp,
				(void(*)(xfs_buf_t*,xfs_log_item_t*))
				xfs_istale_done, (xfs_log_item_t *)iip);
			if (ip != free_ip) {
				xfs_iunlock(ip, XFS_ILOCK_EXCL);
			}
		}

		if (found || pre_flushed)
			xfs_trans_stale_inode_buf(tp, bp);
		xfs_trans_binval(tp, bp);
	}

	kmem_free(ip_found, ninodes * sizeof(xfs_inode_t *));
}

/*
 * This is called to return an inode to the inode free list.
 * The inode should already be truncated to 0 length and have
 * no pages associated with it.  This routine also assumes that
 * the inode is already a part of the transaction.
 *
 * The on-disk copy of the inode will have been added to the list
 * of unlinked inodes in the AGI. We need to remove the inode from
 * that list atomically with respect to freeing it here.
 */
int
xfs_ifree(
	xfs_trans_t	*tp,
	xfs_inode_t	*ip,
	xfs_bmap_free_t	*flist)
{
	int			error;
	int			delete;
	xfs_ino_t		first_ino;

	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));
	ASSERT(ip->i_transp == tp);
	ASSERT(ip->i_d.di_nlink == 0);
	ASSERT(ip->i_d.di_nextents == 0);
	ASSERT(ip->i_d.di_anextents == 0);
	ASSERT((ip->i_d.di_size == 0) ||
	       ((ip->i_d.di_mode & S_IFMT) != S_IFREG));
	ASSERT(ip->i_d.di_nblocks == 0);

	/*
	 * Pull the on-disk inode from the AGI unlinked list.
	 */
	error = xfs_iunlink_remove(tp, ip);
	if (error != 0) {
		return error;
	}

	error = xfs_difree(tp, ip->i_ino, flist, &delete, &first_ino);
	if (error != 0) {
		return error;
	}
	ip->i_d.di_mode = 0;		/* mark incore inode as free */
	ip->i_d.di_flags = 0;
	ip->i_d.di_dmevmask = 0;
	ip->i_d.di_forkoff = 0;		/* mark the attr fork not in use */
	ip->i_df.if_ext_max =
		XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
	ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
	ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
	/*
	 * Bump the generation count so no one will be confused
	 * by reincarnations of this inode.
	 */
	ip->i_d.di_gen++;
	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);

	if (delete) {
		xfs_ifree_cluster(ip, tp, first_ino);
	}

	return 0;
}

/*
 * Reallocate the space for if_broot based on the number of records
 * being added or deleted as indicated in rec_diff.  Move the records
 * and pointers in if_broot to fit the new size.  When shrinking this
 * will eliminate holes between the records and pointers created by
 * the caller.  When growing this will create holes to be filled in
 * by the caller.
 *
 * The caller must not request to add more records than would fit in
 * the on-disk inode root.  If the if_broot is currently NULL, then
 * if we adding records one will be allocated.  The caller must also
 * not request that the number of records go below zero, although
 * it can go to zero.
 *
 * ip -- the inode whose if_broot area is changing
 * ext_diff -- the change in the number of records, positive or negative,
 *	 requested for the if_broot array.
 */
void
xfs_iroot_realloc(
	xfs_inode_t		*ip,
	int			rec_diff,
	int			whichfork)
{
	int			cur_max;
	xfs_ifork_t		*ifp;
	xfs_bmbt_block_t	*new_broot;
	int			new_max;
	size_t			new_size;
	char			*np;
	char			*op;

	/*
	 * Handle the degenerate case quietly.
	 */
	if (rec_diff == 0) {
		return;
	}

	ifp = XFS_IFORK_PTR(ip, whichfork);
	if (rec_diff > 0) {
		/*
		 * If there wasn't any memory allocated before, just
		 * allocate it now and get out.
		 */
		if (ifp->if_broot_bytes == 0) {
			new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(rec_diff);
			ifp->if_broot = (xfs_bmbt_block_t*)kmem_alloc(new_size,
								     KM_SLEEP);
			ifp->if_broot_bytes = (int)new_size;
			return;
		}

		/*
		 * If there is already an existing if_broot, then we need
		 * to realloc() it and shift the pointers to their new
		 * location.  The records don't change location because
		 * they are kept butted up against the btree block header.
		 */
		cur_max = XFS_BMAP_BROOT_MAXRECS(ifp->if_broot_bytes);
		new_max = cur_max + rec_diff;
		new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(new_max);
		ifp->if_broot = (xfs_bmbt_block_t *)
		  kmem_realloc(ifp->if_broot,
				new_size,
				(size_t)XFS_BMAP_BROOT_SPACE_CALC(cur_max), /* old size */
				KM_SLEEP);
		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(ifp->if_broot, 1,
						      ifp->if_broot_bytes);
		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(ifp->if_broot, 1,
						      (int)new_size);
		ifp->if_broot_bytes = (int)new_size;
		ASSERT(ifp->if_broot_bytes <=
			XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ);
		memmove(np, op, cur_max * (uint)sizeof(xfs_dfsbno_t));
		return;
	}

	/*
	 * rec_diff is less than 0.  In this case, we are shrinking the
	 * if_broot buffer.  It must already exist.  If we go to zero
	 * records, just get rid of the root and clear the status bit.
	 */
	ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0));
	cur_max = XFS_BMAP_BROOT_MAXRECS(ifp->if_broot_bytes);
	new_max = cur_max + rec_diff;
	ASSERT(new_max >= 0);
	if (new_max > 0)
		new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(new_max);
	else
		new_size = 0;
	if (new_size > 0) {
		new_broot = (xfs_bmbt_block_t *)kmem_alloc(new_size, KM_SLEEP);
		/*
		 * First copy over the btree block header.
		 */
		memcpy(new_broot, ifp->if_broot, sizeof(xfs_bmbt_block_t));
	} else {
		new_broot = NULL;
		ifp->if_flags &= ~XFS_IFBROOT;
	}

	/*
	 * Only copy the records and pointers if there are any.
	 */
	if (new_max > 0) {
		/*
		 * First copy the records.
		 */
		op = (char *)XFS_BMAP_BROOT_REC_ADDR(ifp->if_broot, 1,
						     ifp->if_broot_bytes);
		np = (char *)XFS_BMAP_BROOT_REC_ADDR(new_broot, 1,
						     (int)new_size);
		memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t));

		/*
		 * Then copy the pointers.
		 */
		op = (char *)XFS_BMAP_BROOT_PTR_ADDR(ifp->if_broot, 1,
						     ifp->if_broot_bytes);
		np = (char *)XFS_BMAP_BROOT_PTR_ADDR(new_broot, 1,
						     (int)new_size);
		memcpy(np, op, new_max * (uint)sizeof(xfs_dfsbno_t));
	}
	kmem_free(ifp->if_broot, ifp->if_broot_bytes);
	ifp->if_broot = new_broot;
	ifp->if_broot_bytes = (int)new_size;
	ASSERT(ifp->if_broot_bytes <=
		XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ);
	return;
}


/*
 * This is called when the amount of space needed for if_extents
 * is increased or decreased.  The change in size is indicated by
 * the number of extents that need to be added or deleted in the
 * ext_diff parameter.
 *
 * If the amount of space needed has decreased below the size of the
 * inline buffer, then switch to using the inline buffer.  Otherwise,
 * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
 * to what is needed.
 *
 * ip -- the inode whose if_extents area is changing
 * ext_diff -- the change in the number of extents, positive or negative,
 *	 requested for the if_extents array.
 */
void
xfs_iext_realloc(
	xfs_inode_t	*ip,
	int		ext_diff,
	int		whichfork)
{
	int		byte_diff;
	xfs_ifork_t	*ifp;
	int		new_size;
	uint		rnew_size;

	if (ext_diff == 0) {
		return;
	}

	ifp = XFS_IFORK_PTR(ip, whichfork);
	byte_diff = ext_diff * (uint)sizeof(xfs_bmbt_rec_t);
	new_size = (int)ifp->if_bytes + byte_diff;
	ASSERT(new_size >= 0);

	if (new_size == 0) {
		if (ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext) {
			ASSERT(ifp->if_real_bytes != 0);
			kmem_free(ifp->if_u1.if_extents, ifp->if_real_bytes);
		}
		ifp->if_u1.if_extents = NULL;
		rnew_size = 0;
	} else if (new_size <= sizeof(ifp->if_u2.if_inline_ext)) {
		/*
		 * If the valid extents can fit in if_inline_ext,
		 * copy them from the malloc'd vector and free it.
		 */
		if (ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext) {
			/*
			 * For now, empty files are format EXTENTS,
			 * so the if_extents pointer is null.
			 */
			if (ifp->if_u1.if_extents) {
				memcpy(ifp->if_u2.if_inline_ext,
					ifp->if_u1.if_extents, new_size);
				kmem_free(ifp->if_u1.if_extents,
					  ifp->if_real_bytes);
			}
			ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
		}
		rnew_size = 0;
	} else {
		rnew_size = new_size;
		if ((rnew_size & (rnew_size - 1)) != 0)
			rnew_size = xfs_iroundup(rnew_size);
		/*
		 * Stuck with malloc/realloc.
		 */
		if (ifp->if_u1.if_extents == ifp->if_u2.if_inline_ext) {
			ifp->if_u1.if_extents = (xfs_bmbt_rec_t *)
				kmem_alloc(rnew_size, KM_SLEEP);
			memcpy(ifp->if_u1.if_extents, ifp->if_u2.if_inline_ext,
			      sizeof(ifp->if_u2.if_inline_ext));
		} else if (rnew_size != ifp->if_real_bytes) {
			ifp->if_u1.if_extents = (xfs_bmbt_rec_t *)
			  kmem_realloc(ifp->if_u1.if_extents,
					rnew_size,
					ifp->if_real_bytes,
					KM_NOFS);
		}
	}
	ifp->if_real_bytes = rnew_size;
	ifp->if_bytes = new_size;
}


/*
 * This is called when the amount of space needed for if_data
 * is increased or decreased.  The change in size is indicated by
 * the number of bytes that need to be added or deleted in the
 * byte_diff parameter.
 *
 * If the amount of space needed has decreased below the size of the
 * inline buffer, then switch to using the inline buffer.  Otherwise,
 * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
 * to what is needed.
 *
 * ip -- the inode whose if_data area is changing
 * byte_diff -- the change in the number of bytes, positive or negative,
 *	 requested for the if_data array.
 */
void
xfs_idata_realloc(
	xfs_inode_t	*ip,
	int		byte_diff,
	int		whichfork)
{
	xfs_ifork_t	*ifp;
	int		new_size;
	int		real_size;

	if (byte_diff == 0) {
		return;
	}

	ifp = XFS_IFORK_PTR(ip, whichfork);
	new_size = (int)ifp->if_bytes + byte_diff;
	ASSERT(new_size >= 0);

	if (new_size == 0) {
		if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
			kmem_free(ifp->if_u1.if_data, ifp->if_real_bytes);
		}
		ifp->if_u1.if_data = NULL;
		real_size = 0;
	} else if (new_size <= sizeof(ifp->if_u2.if_inline_data)) {
		/*
		 * If the valid extents/data can fit in if_inline_ext/data,
		 * copy them from the malloc'd vector and free it.
		 */
		if (ifp->if_u1.if_data == NULL) {
			ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
		} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
			ASSERT(ifp->if_real_bytes != 0);
			memcpy(ifp->if_u2.if_inline_data, ifp->if_u1.if_data,
			      new_size);
			kmem_free(ifp->if_u1.if_data, ifp->if_real_bytes);
			ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
		}
		real_size = 0;
	} else {
		/*
		 * Stuck with malloc/realloc.
		 * For inline data, the underlying buffer must be
		 * a multiple of 4 bytes in size so that it can be
		 * logged and stay on word boundaries.  We enforce
		 * that here.
		 */
		real_size = roundup(new_size, 4);
		if (ifp->if_u1.if_data == NULL) {
			ASSERT(ifp->if_real_bytes == 0);
			ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP);
		} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
			/*
			 * Only do the realloc if the underlying size
			 * is really changing.
			 */
			if (ifp->if_real_bytes != real_size) {
				ifp->if_u1.if_data =
					kmem_realloc(ifp->if_u1.if_data,
							real_size,
							ifp->if_real_bytes,
							KM_SLEEP);
			}
		} else {
			ASSERT(ifp->if_real_bytes == 0);
			ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP);
			memcpy(ifp->if_u1.if_data, ifp->if_u2.if_inline_data,
				ifp->if_bytes);
		}
	}
	ifp->if_real_bytes = real_size;
	ifp->if_bytes = new_size;
	ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
}




/*
 * Map inode to disk block and offset.
 *
 * mp -- the mount point structure for the current file system
 * tp -- the current transaction
 * ino -- the inode number of the inode to be located
 * imap -- this structure is filled in with the information necessary
 *	 to retrieve the given inode from disk
 * flags -- flags to pass to xfs_dilocate indicating whether or not
 *	 lookups in the inode btree were OK or not
 */
int
xfs_imap(
	xfs_mount_t	*mp,
	xfs_trans_t	*tp,
	xfs_ino_t	ino,
	xfs_imap_t	*imap,
	uint		flags)
{
	xfs_fsblock_t	fsbno;
	int		len;
	int		off;
	int		error;

	fsbno = imap->im_blkno ?
		XFS_DADDR_TO_FSB(mp, imap->im_blkno) : NULLFSBLOCK;
	error = xfs_dilocate(mp, tp, ino, &fsbno, &len, &off, flags);
	if (error != 0) {
		return error;
	}
	imap->im_blkno = XFS_FSB_TO_DADDR(mp, fsbno);
	imap->im_len = XFS_FSB_TO_BB(mp, len);
	imap->im_agblkno = XFS_FSB_TO_AGBNO(mp, fsbno);
	imap->im_ioffset = (ushort)off;
	imap->im_boffset = (ushort)(off << mp->m_sb.sb_inodelog);
	return 0;
}

void
xfs_idestroy_fork(
	xfs_inode_t	*ip,
	int		whichfork)
{
	xfs_ifork_t	*ifp;

	ifp = XFS_IFORK_PTR(ip, whichfork);
	if (ifp->if_broot != NULL) {
		kmem_free(ifp->if_broot, ifp->if_broot_bytes);
		ifp->if_broot = NULL;
	}

	/*
	 * If the format is local, then we can't have an extents
	 * array so just look for an inline data array.  If we're
	 * not local then we may or may not have an extents list,
	 * so check and free it up if we do.
	 */
	if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
		if ((ifp->if_u1.if_data != ifp->if_u2.if_inline_data) &&
		    (ifp->if_u1.if_data != NULL)) {
			ASSERT(ifp->if_real_bytes != 0);
			kmem_free(ifp->if_u1.if_data, ifp->if_real_bytes);
			ifp->if_u1.if_data = NULL;
			ifp->if_real_bytes = 0;
		}
	} else if ((ifp->if_flags & XFS_IFEXTENTS) &&
		   (ifp->if_u1.if_extents != NULL) &&
		   (ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext)) {
		ASSERT(ifp->if_real_bytes != 0);
		kmem_free(ifp->if_u1.if_extents, ifp->if_real_bytes);
		ifp->if_u1.if_extents = NULL;
		ifp->if_real_bytes = 0;
	}
	ASSERT(ifp->if_u1.if_extents == NULL ||
	       ifp->if_u1.if_extents == ifp->if_u2.if_inline_ext);
	ASSERT(ifp->if_real_bytes == 0);
	if (whichfork == XFS_ATTR_FORK) {
		kmem_zone_free(xfs_ifork_zone, ip->i_afp);
		ip->i_afp = NULL;
	}
}

/*
 * This is called free all the memory associated with an inode.
 * It must free the inode itself and any buffers allocated for
 * if_extents/if_data and if_broot.  It must also free the lock
 * associated with the inode.
 */
void
xfs_idestroy(
	xfs_inode_t	*ip)
{

	switch (ip->i_d.di_mode & S_IFMT) {
	case S_IFREG:
	case S_IFDIR:
	case S_IFLNK:
		xfs_idestroy_fork(ip, XFS_DATA_FORK);
		break;
	}
	if (ip->i_afp)
		xfs_idestroy_fork(ip, XFS_ATTR_FORK);
	mrfree(&ip->i_lock);
	mrfree(&ip->i_iolock);
	freesema(&ip->i_flock);
#ifdef XFS_BMAP_TRACE
	ktrace_free(ip->i_xtrace);
#endif
#ifdef XFS_BMBT_TRACE
	ktrace_free(ip->i_btrace);
#endif
#ifdef XFS_RW_TRACE
	ktrace_free(ip->i_rwtrace);
#endif
#ifdef XFS_ILOCK_TRACE
	ktrace_free(ip->i_lock_trace);
#endif
#ifdef XFS_DIR2_TRACE
	ktrace_free(ip->i_dir_trace);
#endif
	if (ip->i_itemp) {
		/* XXXdpd should be able to assert this but shutdown
		 * is leaving the AIL behind. */
		ASSERT(((ip->i_itemp->ili_item.li_flags & XFS_LI_IN_AIL) == 0) ||
		       XFS_FORCED_SHUTDOWN(ip->i_mount));
		xfs_inode_item_destroy(ip);
	}
	kmem_zone_free(xfs_inode_zone, ip);
}


/*
 * Increment the pin count of the given buffer.
 * This value is protected by ipinlock spinlock in the mount structure.
 */
void
xfs_ipin(
	xfs_inode_t	*ip)
{
	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE));

	atomic_inc(&ip->i_pincount);
}

/*
 * Decrement the pin count of the given inode, and wake up
 * anyone in xfs_iwait_unpin() if the count goes to 0.  The
 * inode must have been previoulsy pinned with a call to xfs_ipin().
 */
void
xfs_iunpin(
	xfs_inode_t	*ip)
{
	ASSERT(atomic_read(&ip->i_pincount) > 0);

	if (atomic_dec_and_test(&ip->i_pincount)) {
#if XXXKAN
		/*
		 * Should I mark FreeBSD vnode as dirty here?
		 */
		printf("%s:%d: Should I mark FreeBSD vnode as dirty here?\n",
		    __FILE__, __LINE__);
		xfs_vnode_t	*vp = XFS_ITOV_NULL(ip);

		/* make sync come back and flush this inode */
		if (vp) {
			struct inode	*inode = LINVFS_GET_IP(vp);

			if (!(inode->i_state & I_NEW))
				mark_inode_dirty_sync(inode);
		}
#endif

		wakeup(&ip->i_ipin_wait);
	}
}

/*
 * This is called to wait for the given inode to be unpinned.
 * It will sleep until this happens.  The caller must have the
 * inode locked in at least shared mode so that the buffer cannot
 * be subsequently pinned once someone is waiting for it to be
 * unpinned.
 */
STATIC void
xfs_iunpin_wait(
	xfs_inode_t	*ip)
{
	xfs_inode_log_item_t	*iip;
	xfs_lsn_t	lsn;

	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE | MR_ACCESS));

	if (atomic_read(&ip->i_pincount) == 0) {
		return;
	}

	iip = ip->i_itemp;
	if (iip && iip->ili_last_lsn) {
		lsn = iip->ili_last_lsn;
	} else {
		lsn = (xfs_lsn_t)0;
	}

	/*
	 * Give the log a push so we don't wait here too long.
	 */
	xfs_log_force(ip->i_mount, lsn, XFS_LOG_FORCE);

	/*
	 * XXXKAN: xfs_iunpin is not locking inode
	 * at all?
	 */
	while(atomic_read(&ip->i_pincount) != 0)
		tsleep(&ip->i_ipin_wait, PRIBIO, "iunpin", 0);
}


/*
 * xfs_iextents_copy()
 *
 * This is called to copy the REAL extents (as opposed to the delayed
 * allocation extents) from the inode into the given buffer.  It
 * returns the number of bytes copied into the buffer.
 *
 * If there are no delayed allocation extents, then we can just
 * memcpy() the extents into the buffer.  Otherwise, we need to
 * examine each extent in turn and skip those which are delayed.
 */
int
xfs_iextents_copy(
	xfs_inode_t		*ip,
	xfs_bmbt_rec_t		*buffer,
	int			whichfork)
{
	int			copied;
	xfs_bmbt_rec_t		*dest_ep;
	xfs_bmbt_rec_t		*ep;
#ifdef XFS_BMAP_TRACE
	static char		fname[] = "xfs_iextents_copy";
#endif
	int			i;
	xfs_ifork_t		*ifp;
	int			nrecs;
	xfs_fsblock_t		start_block;

	ifp = XFS_IFORK_PTR(ip, whichfork);
	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE|MR_ACCESS));
	ASSERT(ifp->if_bytes > 0);

	nrecs = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
	xfs_bmap_trace_exlist(fname, ip, nrecs, whichfork);
	ASSERT(nrecs > 0);

	/*
	 * There are some delayed allocation extents in the
	 * inode, so copy the extents one at a time and skip
	 * the delayed ones.  There must be at least one
	 * non-delayed extent.
	 */
	ep = ifp->if_u1.if_extents;
	dest_ep = buffer;
	copied = 0;
	for (i = 0; i < nrecs; i++) {
		start_block = xfs_bmbt_get_startblock(ep);
		if (ISNULLSTARTBLOCK(start_block)) {
			/*
			 * It's a delayed allocation extent, so skip it.
			 */
			ep++;
			continue;
		}

		/* Translate to on disk format */
		put_unaligned(INT_GET(ep->l0, ARCH_CONVERT),
			      (__uint64_t*)&dest_ep->l0);
		put_unaligned(INT_GET(ep->l1, ARCH_CONVERT),
			      (__uint64_t*)&dest_ep->l1);
		dest_ep++;
		ep++;
		copied++;
	}
	ASSERT(copied != 0);
	xfs_validate_extents(buffer, copied, 1, XFS_EXTFMT_INODE(ip));

	return (copied * (uint)sizeof(xfs_bmbt_rec_t));
}

/*
 * Each of the following cases stores data into the same region
 * of the on-disk inode, so only one of them can be valid at
 * any given time. While it is possible to have conflicting formats
 * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
 * in EXTENTS format, this can only happen when the fork has
 * changed formats after being modified but before being flushed.
 * In these cases, the format always takes precedence, because the
 * format indicates the current state of the fork.
 */
/*ARGSUSED*/
STATIC int
xfs_iflush_fork(
	xfs_inode_t		*ip,
	xfs_dinode_t		*dip,
	xfs_inode_log_item_t	*iip,
	int			whichfork,
	xfs_buf_t		*bp)
{
	char			*cp;
	xfs_ifork_t		*ifp;
	xfs_mount_t		*mp;
#ifdef XFS_TRANS_DEBUG
	int			first;
#endif
	static const short	brootflag[2] =
		{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
	static const short	dataflag[2] =
		{ XFS_ILOG_DDATA, XFS_ILOG_ADATA };
	static const short	extflag[2] =
		{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };

	if (iip == NULL)
		return 0;
	ifp = XFS_IFORK_PTR(ip, whichfork);
	/*
	 * This can happen if we gave up in iformat in an error path,
	 * for the attribute fork.
	 */
	if (ifp == NULL) {
		ASSERT(whichfork == XFS_ATTR_FORK);
		return 0;
	}
	cp = XFS_DFORK_PTR_ARCH(dip, whichfork, ARCH_CONVERT);
	mp = ip->i_mount;
	switch (XFS_IFORK_FORMAT(ip, whichfork)) {
	case XFS_DINODE_FMT_LOCAL:
		if ((iip->ili_format.ilf_fields & dataflag[whichfork]) &&
		    (ifp->if_bytes > 0)) {
			ASSERT(ifp->if_u1.if_data != NULL);
			ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
			memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes);
		}
		if (whichfork == XFS_DATA_FORK) {
			if (unlikely(XFS_DIR_SHORTFORM_VALIDATE_ONDISK(mp, dip))) {
				XFS_ERROR_REPORT("xfs_iflush_fork",
						 XFS_ERRLEVEL_LOW, mp);
				return XFS_ERROR(EFSCORRUPTED);
			}
		}
		break;

	case XFS_DINODE_FMT_EXTENTS:
		ASSERT((ifp->if_flags & XFS_IFEXTENTS) ||
		       !(iip->ili_format.ilf_fields & extflag[whichfork]));
		ASSERT((ifp->if_u1.if_extents != NULL) || (ifp->if_bytes == 0));
		ASSERT((ifp->if_u1.if_extents == NULL) || (ifp->if_bytes > 0));
		if ((iip->ili_format.ilf_fields & extflag[whichfork]) &&
		    (ifp->if_bytes > 0)) {
			ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) > 0);
			(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
				whichfork);
		}
		break;

	case XFS_DINODE_FMT_BTREE:
		if ((iip->ili_format.ilf_fields & brootflag[whichfork]) &&
		    (ifp->if_broot_bytes > 0)) {
			ASSERT(ifp->if_broot != NULL);
			ASSERT(ifp->if_broot_bytes <=
			       (XFS_IFORK_SIZE(ip, whichfork) +
				XFS_BROOT_SIZE_ADJ));
			xfs_bmbt_to_bmdr(ifp->if_broot, ifp->if_broot_bytes,
				(xfs_bmdr_block_t *)cp,
				XFS_DFORK_SIZE_ARCH(dip, mp, whichfork, ARCH_CONVERT));
		}
		break;

	case XFS_DINODE_FMT_DEV:
		if (iip->ili_format.ilf_fields & XFS_ILOG_DEV) {
			ASSERT(whichfork == XFS_DATA_FORK);
			INT_SET(dip->di_u.di_dev, ARCH_CONVERT, ip->i_df.if_u2.if_rdev);
		}
		break;

	case XFS_DINODE_FMT_UUID:
		if (iip->ili_format.ilf_fields & XFS_ILOG_UUID) {
			ASSERT(whichfork == XFS_DATA_FORK);
			memcpy(&dip->di_u.di_muuid, &ip->i_df.if_u2.if_uuid,
				sizeof(uuid_t));
		}
		break;

	default:
		ASSERT(0);
		break;
	}

	return 0;
}

/*
 * xfs_iflush() will write a modified inode's changes out to the
 * inode's on disk home.  The caller must have the inode lock held
 * in at least shared mode and the inode flush semaphore must be
 * held as well.  The inode lock will still be held upon return from
 * the call and the caller is free to unlock it.
 * The inode flush lock will be unlocked when the inode reaches the disk.
 * The flags indicate how the inode's buffer should be written out.
 */
int
xfs_iflush(
	xfs_inode_t		*ip,
	uint			flags)
{
	xfs_inode_log_item_t	*iip;
	xfs_buf_t		*bp;
	xfs_dinode_t		*dip;
	xfs_mount_t		*mp;
	int			error;
	/* REFERENCED */
	xfs_chash_t		*ch;
	xfs_inode_t		*iq;
	int			clcount;	/* count of inodes clustered */
	int			bufwasdelwri;
	enum { INT_DELWRI = (1 << 0), INT_ASYNC = (1 << 1) };
	SPLDECL(s);

	XFS_STATS_INC(xs_iflush_count);

	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE|MR_ACCESS));
	ASSERT(valusema(&ip->i_flock) <= 0);
	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
	       ip->i_d.di_nextents > ip->i_df.if_ext_max);

	iip = ip->i_itemp;
	mp = ip->i_mount;

	/*
	 * If the inode isn't dirty, then just release the inode
	 * flush lock and do nothing.
	 */
	if ((ip->i_update_core == 0) &&
	    ((iip == NULL) || !(iip->ili_format.ilf_fields & XFS_ILOG_ALL))) {
		ASSERT((iip != NULL) ?
			 !(iip->ili_item.li_flags & XFS_LI_IN_AIL) : 1);
		xfs_ifunlock(ip);
		return 0;
	}

	/*
	 * We can't flush the inode until it is unpinned, so
	 * wait for it.  We know noone new can pin it, because
	 * we are holding the inode lock shared and you need
	 * to hold it exclusively to pin the inode.
	 */
	xfs_iunpin_wait(ip);

	/*
	 * This may have been unpinned because the filesystem is shutting
	 * down forcibly. If that's the case we must not write this inode
	 * to disk, because the log record didn't make it to disk!
	 */
	if (XFS_FORCED_SHUTDOWN(mp)) {
		ip->i_update_core = 0;
		if (iip)
			iip->ili_format.ilf_fields = 0;
		xfs_ifunlock(ip);
		return XFS_ERROR(EIO);
	}

	/*
	 * Get the buffer containing the on-disk inode.
	 */
	error = xfs_itobp(mp, NULL, ip, &dip, &bp, 0);
	if (error != 0) {
		xfs_ifunlock(ip);
		return error;
	}

	/*
	 * Decide how buffer will be flushed out.  This is done before
	 * the call to xfs_iflush_int because this field is zeroed by it.
	 */
	if (iip != NULL && iip->ili_format.ilf_fields != 0) {
		/*
		 * Flush out the inode buffer according to the directions
		 * of the caller.  In the cases where the caller has given
		 * us a choice choose the non-delwri case.  This is because
		 * the inode is in the AIL and we need to get it out soon.
		 */
		switch (flags) {
		case XFS_IFLUSH_SYNC:
		case XFS_IFLUSH_DELWRI_ELSE_SYNC:
			flags = 0;
			break;
		case XFS_IFLUSH_ASYNC:
		case XFS_IFLUSH_DELWRI_ELSE_ASYNC:
			flags = INT_ASYNC;
			break;
		case XFS_IFLUSH_DELWRI:
			flags = INT_DELWRI;
			break;
		default:
			ASSERT(0);
			flags = 0;
			break;
		}
	} else {
		switch (flags) {
		case XFS_IFLUSH_DELWRI_ELSE_SYNC:
		case XFS_IFLUSH_DELWRI_ELSE_ASYNC:
		case XFS_IFLUSH_DELWRI:
			flags = INT_DELWRI;
			break;
		case XFS_IFLUSH_ASYNC:
			flags = INT_ASYNC;
			break;
		case XFS_IFLUSH_SYNC:
			flags = 0;
			break;
		default:
			ASSERT(0);
			flags = 0;
			break;
		}
	}

	/*
	 * First flush out the inode that xfs_iflush was called with.
	 */
	error = xfs_iflush_int(ip, bp);
	if (error) {
		goto corrupt_out;
	}

	/*
	 * inode clustering:
	 * see if other inodes can be gathered into this write
	 */

	ip->i_chash->chl_buf = bp;

	ch = XFS_CHASH(mp, ip->i_blkno);
	s = mutex_spinlock(&ch->ch_lock);

	clcount = 0;
	for (iq = ip->i_cnext; iq != ip; iq = iq->i_cnext) {
		/*
		 * Do an un-protected check to see if the inode is dirty and
		 * is a candidate for flushing.  These checks will be repeated
		 * later after the appropriate locks are acquired.
		 */
		iip = iq->i_itemp;
		if ((iq->i_update_core == 0) &&
		    ((iip == NULL) ||
		     !(iip->ili_format.ilf_fields & XFS_ILOG_ALL)) &&
		      xfs_ipincount(iq) == 0) {
			continue;
		}

		/*
		 * Try to get locks.  If any are unavailable,
		 * then this inode cannot be flushed and is skipped.
		 */

		/* get inode locks (just i_lock) */
		if (xfs_ilock_nowait(iq, XFS_ILOCK_SHARED)) {
			/* get inode flush lock */
			if (xfs_iflock_nowait(iq)) {
				/* check if pinned */
				if (xfs_ipincount(iq) == 0) {
					/* arriving here means that
					 * this inode can be flushed.
					 * first re-check that it's
					 * dirty
					 */
					iip = iq->i_itemp;
					if ((iq->i_update_core != 0)||
					    ((iip != NULL) &&
					     (iip->ili_format.ilf_fields & XFS_ILOG_ALL))) {
						clcount++;
						error = xfs_iflush_int(iq, bp);
						if (error) {
							xfs_iunlock(iq,
								    XFS_ILOCK_SHARED);
							goto cluster_corrupt_out;
						}
					} else {
						xfs_ifunlock(iq);
					}
				} else {
					xfs_ifunlock(iq);
				}
			}
			xfs_iunlock(iq, XFS_ILOCK_SHARED);
		}
	}
	mutex_spinunlock(&ch->ch_lock, s);

	if (clcount) {
		XFS_STATS_INC(xs_icluster_flushcnt);
		XFS_STATS_ADD(xs_icluster_flushinode, clcount);
	}

	/*
	 * If the buffer is pinned then push on the log so we won't
	 * get stuck waiting in the write for too long.
	 */
	if (XFS_BUF_ISPINNED(bp)){
		xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE);
	}

	if (flags & INT_DELWRI) {
		xfs_bdwrite(mp, bp);
	} else if (flags & INT_ASYNC) {
		xfs_bawrite(mp, bp);
	} else {
		error = xfs_bwrite(mp, bp);
	}
	return error;

corrupt_out:
	xfs_buf_relse(bp);
	xfs_force_shutdown(mp, XFS_CORRUPT_INCORE);
	xfs_iflush_abort(ip);
	/*
	 * Unlocks the flush lock
	 */
	return XFS_ERROR(EFSCORRUPTED);

cluster_corrupt_out:
	/* Corruption detected in the clustering loop.  Invalidate the
	 * inode buffer and shut down the filesystem.
	 */
	mutex_spinunlock(&ch->ch_lock, s);

	/*
	 * Clean up the buffer.  If it was B_DELWRI, just release it --
	 * brelse can handle it with no problems.  If not, shut down the
	 * filesystem before releasing the buffer.
	 */
	if ((bufwasdelwri= XFS_BUF_ISDELAYWRITE(bp))) {
		xfs_buf_relse(bp);
	}

	xfs_force_shutdown(mp, XFS_CORRUPT_INCORE);

	if(!bufwasdelwri)  {
		/*
		 * Just like incore_relse: if we have b_iodone functions,
		 * mark the buffer as an error and call them.  Otherwise
		 * mark it as stale and brelse.
		 */
		if (XFS_BUF_IODONE_FUNC(bp)) {
			XFS_BUF_CLR_BDSTRAT_FUNC(bp);
			XFS_BUF_UNDONE(bp);
			XFS_BUF_STALE(bp);
			XFS_BUF_SHUT(bp);
			XFS_BUF_ERROR(bp,EIO);
			xfs_biodone(bp);
		} else {
			XFS_BUF_STALE(bp);
			xfs_buf_relse(bp);
		}
	}

	xfs_iflush_abort(iq);
	/*
	 * Unlocks the flush lock
	 */
	return XFS_ERROR(EFSCORRUPTED);
}


STATIC int
xfs_iflush_int(
	xfs_inode_t		*ip,
	xfs_buf_t		*bp)
{
	xfs_inode_log_item_t	*iip;
	xfs_dinode_t		*dip;
	xfs_mount_t		*mp;
#ifdef XFS_TRANS_DEBUG
	int			first;
#endif
	SPLDECL(s);

	ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE|MR_ACCESS));
	ASSERT(valusema(&ip->i_flock) <= 0);
	ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
	       ip->i_d.di_nextents > ip->i_df.if_ext_max);

	iip = ip->i_itemp;
	mp = ip->i_mount;


	/*
	 * If the inode isn't dirty, then just release the inode
	 * flush lock and do nothing.
	 */
	if ((ip->i_update_core == 0) &&
	    ((iip == NULL) || !(iip->ili_format.ilf_fields & XFS_ILOG_ALL))) {
		xfs_ifunlock(ip);
		return 0;
	}

	/* set *dip = inode's place in the buffer */
	dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_boffset);

	/*
	 * Clear i_update_core before copying out the data.
	 * This is for coordination with our timestamp updates
	 * that don't hold the inode lock. They will always
	 * update the timestamps BEFORE setting i_update_core,
	 * so if we clear i_update_core after they set it we
	 * are guaranteed to see their updates to the timestamps.
	 * I believe that this depends on strongly ordered memory
	 * semantics, but we have that.  We use the SYNCHRONIZE
	 * macro to make sure that the compiler does not reorder
	 * the i_update_core access below the data copy below.
	 */
	ip->i_update_core = 0;
	SYNCHRONIZE();

	if (XFS_TEST_ERROR(INT_GET(dip->di_core.di_magic,ARCH_CONVERT) != XFS_DINODE_MAGIC,
			       mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
		xfs_cmn_err(XFS_PTAG_IFLUSH, CE_ALERT, mp,
		    "xfs_iflush: Bad inode %Lu magic number 0x%x, ptr 0x%p",
			ip->i_ino, (int) INT_GET(dip->di_core.di_magic, ARCH_CONVERT), dip);
		goto corrupt_out;
	}
	if (XFS_TEST_ERROR(ip->i_d.di_magic != XFS_DINODE_MAGIC,
				mp, XFS_ERRTAG_IFLUSH_2, XFS_RANDOM_IFLUSH_2)) {
		xfs_cmn_err(XFS_PTAG_IFLUSH, CE_ALERT, mp,
			"xfs_iflush: Bad inode %Lu, ptr 0x%p, magic number 0x%x",
			ip->i_ino, ip, ip->i_d.di_magic);
		goto corrupt_out;
	}
	if ((ip->i_d.di_mode & S_IFMT) == S_IFREG) {
		if (XFS_TEST_ERROR(
		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
		    mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
			xfs_cmn_err(XFS_PTAG_IFLUSH, CE_ALERT, mp,
				"xfs_iflush: Bad regular inode %Lu, ptr 0x%p",
				ip->i_ino, ip);
			goto corrupt_out;
		}
	} else if ((ip->i_d.di_mode & S_IFMT) == S_IFDIR) {
		if (XFS_TEST_ERROR(
		    (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
		    (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
		    (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
		    mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
			xfs_cmn_err(XFS_PTAG_IFLUSH, CE_ALERT, mp,
				"xfs_iflush: Bad directory inode %Lu, ptr 0x%p",
				ip->i_ino, ip);
			goto corrupt_out;
		}
	}
	if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
				ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
				XFS_RANDOM_IFLUSH_5)) {
		xfs_cmn_err(XFS_PTAG_IFLUSH, CE_ALERT, mp,
			"xfs_iflush: detected corrupt incore inode %Lu, total extents = %d, nblocks = %Ld, ptr 0x%p",
			ip->i_ino,
			ip->i_d.di_nextents + ip->i_d.di_anextents,
			ip->i_d.di_nblocks,
			ip);
		goto corrupt_out;
	}
	if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
				mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
		xfs_cmn_err(XFS_PTAG_IFLUSH, CE_ALERT, mp,
			"xfs_iflush: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
			ip->i_ino, ip->i_d.di_forkoff, ip);
		goto corrupt_out;
	}
	/*
	 * bump the flush iteration count, used to detect flushes which
	 * postdate a log record during recovery.
	 */

	ip->i_d.di_flushiter++;

	/*
	 * Copy the dirty parts of the inode into the on-disk
	 * inode.  We always copy out the core of the inode,
	 * because if the inode is dirty at all the core must
	 * be.
	 */
	xfs_xlate_dinode_core((xfs_caddr_t)&(dip->di_core), &(ip->i_d),
		-1, ARCH_CONVERT);

	/* Wrap, we never let the log put out DI_MAX_FLUSH */
	if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
		ip->i_d.di_flushiter = 0;

	/*
	 * If this is really an old format inode and the superblock version
	 * has not been updated to support only new format inodes, then
	 * convert back to the old inode format.  If the superblock version
	 * has been updated, then make the conversion permanent.
	 */
	ASSERT(ip->i_d.di_version == XFS_DINODE_VERSION_1 ||
	       XFS_SB_VERSION_HASNLINK(&mp->m_sb));
	if (ip->i_d.di_version == XFS_DINODE_VERSION_1) {
		if (!XFS_SB_VERSION_HASNLINK(&mp->m_sb)) {
			/*
			 * Convert it back.
			 */
			ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
			INT_SET(dip->di_core.di_onlink, ARCH_CONVERT, ip->i_d.di_nlink);
		} else {
			/*
			 * The superblock version has already been bumped,
			 * so just make the conversion to the new inode
			 * format permanent.
			 */
			ip->i_d.di_version = XFS_DINODE_VERSION_2;
			INT_SET(dip->di_core.di_version, ARCH_CONVERT, XFS_DINODE_VERSION_2);
			ip->i_d.di_onlink = 0;
			INT_ZERO(dip->di_core.di_onlink, ARCH_CONVERT);
			memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
			memset(&(dip->di_core.di_pad[0]), 0,
			      sizeof(dip->di_core.di_pad));
			ASSERT(ip->i_d.di_projid == 0);
		}
	}

	if (xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK, bp) == EFSCORRUPTED) {
		goto corrupt_out;
	}

	if (XFS_IFORK_Q(ip)) {
		/*
		 * The only error from xfs_iflush_fork is on the data fork.
		 */
		(void) xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK, bp);
	}
	xfs_inobp_check(mp, bp);

	/*
	 * We've recorded everything logged in the inode, so we'd
	 * like to clear the ilf_fields bits so we don't log and
	 * flush things unnecessarily.  However, we can't stop
	 * logging all this information until the data we've copied
	 * into the disk buffer is written to disk.  If we did we might
	 * overwrite the copy of the inode in the log with all the
	 * data after re-logging only part of it, and in the face of
	 * a crash we wouldn't have all the data we need to recover.
	 *
	 * What we do is move the bits to the ili_last_fields field.
	 * When logging the inode, these bits are moved back to the
	 * ilf_fields field.  In the xfs_iflush_done() routine we
	 * clear ili_last_fields, since we know that the information
	 * those bits represent is permanently on disk.  As long as
	 * the flush completes before the inode is logged again, then
	 * both ilf_fields and ili_last_fields will be cleared.
	 *
	 * We can play with the ilf_fields bits here, because the inode
	 * lock must be held exclusively in order to set bits there
	 * and the flush lock protects the ili_last_fields bits.
	 * Set ili_logged so the flush done
	 * routine can tell whether or not to look in the AIL.
	 * Also, store the current LSN of the inode so that we can tell
	 * whether the item has moved in the AIL from xfs_iflush_done().
	 * In order to read the lsn we need the AIL lock, because
	 * it is a 64 bit value that cannot be read atomically.
	 */
	if (iip != NULL && iip->ili_format.ilf_fields != 0) {
		iip->ili_last_fields = iip->ili_format.ilf_fields;
		iip->ili_format.ilf_fields = 0;
		iip->ili_logged = 1;

		ASSERT(sizeof(xfs_lsn_t) == 8);	/* don't lock if it shrinks */
		AIL_LOCK(mp,s);
		iip->ili_flush_lsn = iip->ili_item.li_lsn;
		AIL_UNLOCK(mp, s);

		/*
		 * Attach the function xfs_iflush_done to the inode's
		 * buffer.  This will remove the inode from the AIL
		 * and unlock the inode's flush lock when the inode is
		 * completely written to disk.
		 */
		xfs_buf_attach_iodone(bp, (void(*)(xfs_buf_t*,xfs_log_item_t*))
				      xfs_iflush_done, (xfs_log_item_t *)iip);

		ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
		ASSERT(XFS_BUF_IODONE_FUNC(bp) != NULL);
	} else {
		/*
		 * We're flushing an inode which is not in the AIL and has
		 * not been logged but has i_update_core set.  For this
		 * case we can use a B_DELWRI flush and immediately drop
		 * the inode flush lock because we can avoid the whole
		 * AIL state thing.  It's OK to drop the flush lock now,
		 * because we've already locked the buffer and to do anything
		 * you really need both.
		 */
		if (iip != NULL) {
			ASSERT(iip->ili_logged == 0);
			ASSERT(iip->ili_last_fields == 0);
			ASSERT((iip->ili_item.li_flags & XFS_LI_IN_AIL) == 0);
		}
		xfs_ifunlock(ip);
	}

	return 0;

corrupt_out:
	return XFS_ERROR(EFSCORRUPTED);
}

/*
 * Flush all inactive inodes in mp.  Return true if no user references
 * were found, false otherwise.
 */
int
xfs_iflush_all(
	xfs_mount_t	*mp,
	int		flag)
{
	int		busy;
	int		done;
	int		purged;
	xfs_inode_t	*ip;
	vmap_t		vmap;
	xfs_vnode_t	*vp;

	busy = done = 0;
	while (!done) {
		purged = 0;
		XFS_MOUNT_ILOCK(mp);
		ip = mp->m_inodes;
		if (ip == NULL) {
			break;
		}
		do {
			/* Make sure we skip markers inserted by sync */
			if (ip->i_mount == NULL) {
				ip = ip->i_mnext;
				continue;
			}

			/*
			 * It's up to our caller to purge the root
			 * and quota vnodes later.
			 */
			vp = XFS_ITOV_NULL(ip);

			if (!vp) {
				XFS_MOUNT_IUNLOCK(mp);
				xfs_finish_reclaim(ip, 0, XFS_IFLUSH_ASYNC);
				purged = 1;
				break;
			}

			if (vn_count(vp) != 0) {
				if (vn_count(vp) == 1 &&
				    (ip == mp->m_rootip ||
				     (mp->m_quotainfo &&
				      (ip->i_ino == mp->m_sb.sb_uquotino ||
				       ip->i_ino == mp->m_sb.sb_gquotino)))) {

					ip = ip->i_mnext;
					continue;
				}
				if (!(flag & XFS_FLUSH_ALL)) {
					busy = 1;
					done = 1;
					break;
				}
				/*
				 * Ignore busy inodes but continue flushing
				 * others.
				 */
				ip = ip->i_mnext;
				continue;
			}
			/*
			 * Sample vp mapping while holding mp locked on MP
			 * systems, so we don't purge a reclaimed or
			 * nonexistent vnode.  We break from the loop
			 * since we know that we modify
			 * it by pulling ourselves from it in xfs_reclaim()
			 * called via vn_purge() below.  Set ip to the next
			 * entry in the list anyway so we'll know below
			 * whether we reached the end or not.
			 */
			VMAP(vp, vmap);
			XFS_MOUNT_IUNLOCK(mp);

			vn_purge(vp, &vmap);

			purged = 1;
			break;
		} while (ip != mp->m_inodes);
		/*
		 * We need to distinguish between when we exit the loop
		 * after a purge and when we simply hit the end of the
		 * list.  We can't use the (ip == mp->m_inodes) test,
		 * because when we purge an inode at the start of the list
		 * the next inode on the list becomes mp->m_inodes.  That
		 * would cause such a test to bail out early.  The purged
		 * variable tells us how we got out of the loop.
		 */
		if (!purged) {
			done = 1;
		}
	}
	XFS_MOUNT_IUNLOCK(mp);
	return !busy;
}


/*
 * xfs_iaccess: check accessibility of inode for mode.
 */
int
xfs_iaccess(
	xfs_inode_t	*ip,
	mode_t		mode,
	cred_t		*cr)
{
	xfs_vnode_t	*vp;
	int		error;
	mode_t		imode;

	vp = XFS_ITOV(ip);
	imode = (ip->i_d.di_mode & MODEMASK) | VTTOIF(vp->v_type);

	if (mode & S_IWUSR) {
		xfs_mount_t	*mp = ip->i_mount;

		if ((XVFSTOMNT(XFS_MTOVFS(mp))->mnt_flag & MNT_RDONLY) &&
		    (S_ISREG(imode) || S_ISDIR(imode) || S_ISLNK(imode)))
			return XFS_ERROR(EROFS);

#if XXXKAN
		if (IS_IMMUTABLE(inode))
			return XFS_ERROR(EACCES);
#endif
	}

	/*
	 * If there's an Access Control List it's used instead of
	 * the mode bits.
	 */
	if ((error = _ACL_XFS_IACCESS(ip, mode, cr)) != -1)
		return error ? XFS_ERROR(error) : 0;


	error = vaccess(vp->v_type, imode, ip->i_d.di_uid, ip->i_d.di_gid,
	    mode, cr, NULL);

	return (error);
}

/*
 * xfs_iroundup: round up argument to next power of two
 */
uint
xfs_iroundup(
	uint	v)
{
	int i;
	uint m;

	if ((v & (v - 1)) == 0)
		return v;
	ASSERT((v & 0x80000000) == 0);
	if ((v & (v + 1)) == 0)
		return v + 1;
	for (i = 0, m = 1; i < 31; i++, m <<= 1) {
		if (v & m)
			continue;
		v |= m;
		if ((v & (v + 1)) == 0)
			return v + 1;
	}
	ASSERT(0);
	return( 0 );
}

/*
 * Change the requested timestamp in the given inode.
 * We don't lock across timestamp updates, and we don't log them but
 * we do record the fact that there is dirty information in core.
 *
 * NOTE -- callers MUST combine XFS_ICHGTIME_MOD or XFS_ICHGTIME_CHG
 *		with XFS_ICHGTIME_ACC to be sure that access time
 *		update will take.  Calling first with XFS_ICHGTIME_ACC
 *		and then XFS_ICHGTIME_MOD may fail to modify the access
 *		timestamp if the filesystem is mounted noacctm.
 */
void
xfs_ichgtime(xfs_inode_t *ip,
	     int flags)
{
	timespec_t	tv;
	xfs_vnode_t	*vp = XFS_ITOV(ip);
	/*
	 * We're not supposed to change timestamps in readonly-mounted
	 * filesystems.  Throw it away if anyone asks us.
	 */
	if (unlikely(vp->v_vfsp->vfs_flag & VFS_RDONLY))
		return;

	/*
	 * Don't update access timestamps on reads if mounted "noatime"
	 * Throw it away if anyone asks us.
	 */
	if ((ip->i_mount->m_flags & XFS_MOUNT_NOATIME ||
	    (ip->i_d.di_flags & XFS_DIFLAG_NOATIME)) &&
	    ((flags & (XFS_ICHGTIME_ACC|XFS_ICHGTIME_MOD|XFS_ICHGTIME_CHG))
			== XFS_ICHGTIME_ACC))
		return;

	nanotime(&tv);
	if (flags & XFS_ICHGTIME_MOD) {
		VN_MTIMESET(vp, &tv);
		ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec;
	}
	if (flags & XFS_ICHGTIME_ACC) {
		VN_ATIMESET(vp, &tv);
		ip->i_d.di_atime.t_sec = (__int32_t)tv.tv_sec;
	}
	if (flags & XFS_ICHGTIME_CHG) {
		VN_CTIMESET(vp, &tv);
		ip->i_d.di_ctime.t_sec = (__int32_t)tv.tv_sec;
	}

	/*
	 * We update the i_update_core field _after_ changing
	 * the timestamps in order to coordinate properly with
	 * xfs_iflush() so that we don't lose timestamp updates.
	 * This keeps us from having to hold the inode lock
	 * while doing this.  We use the SYNCHRONIZE macro to
	 * ensure that the compiler does not reorder the update
	 * of i_update_core above the timestamp updates above.
	 */
	SYNCHRONIZE();
	ip->i_update_core = 1;
#if XXXKAN
	if (!(inode->i_state & I_LOCK))
		mark_inode_dirty_sync(inode);

	printf("xfs_ichgtime mark vnode dirty\n");
#endif
}

#ifdef XFS_ILOCK_TRACE
ktrace_t	*xfs_ilock_trace_buf;

void
xfs_ilock_trace(xfs_inode_t *ip, int lock, unsigned int lockflags, inst_t *ra)
{
	ktrace_enter(ip->i_lock_trace,
		     (void *)ip,
		     (void *)(unsigned long)lock, /* 1 = LOCK, 3=UNLOCK, etc */
		     (void *)(unsigned long)lockflags, /* XFS_ILOCK_EXCL etc */
		     (void *)ra,		/* caller of ilock */
		     (void *)(unsigned long)current_cpu(),
		     (void *)(unsigned long)current_pid(),
		     0,0,0,0,0,0,0,0,0,0);
}
#endif