fs/xfs/xfs_inode_item.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
  * All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms 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.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write the Free Software Foundation,
  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 #include "xfs.h"
 #include "xfs_fs.h"
 #include "xfs_format.h"
 #include "xfs_log_format.h"
 #include "xfs_trans_resv.h"
 #include "xfs_mount.h"
 #include "xfs_inode.h"
 #include "xfs_trans.h"
 #include "xfs_inode_item.h"
 #include "xfs_error.h"
 #include "xfs_trace.h"
 #include "xfs_trans_priv.h"
 #include "xfs_log.h"


 kmem_zone_t	*xfs_ili_zone;		/* inode log item zone */

 static inline struct xfs_inode_log_item *INODE_ITEM(struct xfs_log_item *lip)
 {
 	return container_of(lip, struct xfs_inode_log_item, ili_item);
 }

 STATIC void
 xfs_inode_item_data_fork_size(
 	struct xfs_inode_log_item *iip,
 	int			*nvecs,
 	int			*nbytes)
 {
 	struct xfs_inode	*ip = iip->ili_inode;

 	switch (ip->i_d.di_format) {
 	case XFS_DINODE_FMT_EXTENTS:
 		if ((iip->ili_fields & XFS_ILOG_DEXT) &&
 		    ip->i_d.di_nextents > 0 &&
 		    ip->i_df.if_bytes > 0) {
 			/* worst case, doesn't subtract delalloc extents */
 			*nbytes += XFS_IFORK_DSIZE(ip);
 			*nvecs += 1;
 		}
 		break;
 	case XFS_DINODE_FMT_BTREE:
 		if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
 		    ip->i_df.if_broot_bytes > 0) {
 			*nbytes += ip->i_df.if_broot_bytes;
 			*nvecs += 1;
 		}
 		break;
 	case XFS_DINODE_FMT_LOCAL:
 		if ((iip->ili_fields & XFS_ILOG_DDATA) &&
 		    ip->i_df.if_bytes > 0) {
 			*nbytes += roundup(ip->i_df.if_bytes, 4);
 			*nvecs += 1;
 		}
 		break;

 	case XFS_DINODE_FMT_DEV:
 	case XFS_DINODE_FMT_UUID:
 		break;
 	default:
 		ASSERT(0);
 		break;
 	}
 }

 STATIC void
 xfs_inode_item_attr_fork_size(
 	struct xfs_inode_log_item *iip,
 	int			*nvecs,
 	int			*nbytes)
 {
 	struct xfs_inode	*ip = iip->ili_inode;

 	switch (ip->i_d.di_aformat) {
 	case XFS_DINODE_FMT_EXTENTS:
 		if ((iip->ili_fields & XFS_ILOG_AEXT) &&
 		    ip->i_d.di_anextents > 0 &&
 		    ip->i_afp->if_bytes > 0) {
 			/* worst case, doesn't subtract unused space */
 			*nbytes += XFS_IFORK_ASIZE(ip);
 			*nvecs += 1;
 		}
 		break;
 	case XFS_DINODE_FMT_BTREE:
 		if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
 		    ip->i_afp->if_broot_bytes > 0) {
 			*nbytes += ip->i_afp->if_broot_bytes;
 			*nvecs += 1;
 		}
 		break;
 	case XFS_DINODE_FMT_LOCAL:
 		if ((iip->ili_fields & XFS_ILOG_ADATA) &&
 		    ip->i_afp->if_bytes > 0) {
 			*nbytes += roundup(ip->i_afp->if_bytes, 4);
 			*nvecs += 1;
 		}
 		break;
 	default:
 		ASSERT(0);
 		break;
 	}
 }

 /*
  * This returns the number of iovecs needed to log the given inode item.
  *
  * We need one iovec for the inode log format structure, one for the
  * inode core, and possibly one for the inode data/extents/b-tree root
  * and one for the inode attribute data/extents/b-tree root.
  */
 STATIC void
 xfs_inode_item_size(
 	struct xfs_log_item	*lip,
 	int			*nvecs,
 	int			*nbytes)
 {
 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
 	struct xfs_inode	*ip = iip->ili_inode;

 	*nvecs += 2;
 	*nbytes += sizeof(struct xfs_inode_log_format) +
 		   xfs_icdinode_size(ip->i_d.di_version);

 	xfs_inode_item_data_fork_size(iip, nvecs, nbytes);
 	if (XFS_IFORK_Q(ip))
 		xfs_inode_item_attr_fork_size(iip, nvecs, nbytes);
 }

 STATIC void
 xfs_inode_item_format_data_fork(
 	struct xfs_inode_log_item *iip,
 	struct xfs_inode_log_format *ilf,
 	struct xfs_log_vec	*lv,
 	struct xfs_log_iovec	**vecp)
 {
 	struct xfs_inode	*ip = iip->ili_inode;
 	size_t			data_bytes;

 	switch (ip->i_d.di_format) {
 	case XFS_DINODE_FMT_EXTENTS:
 		iip->ili_fields &=
 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
 			  XFS_ILOG_DEV | XFS_ILOG_UUID);

 		if ((iip->ili_fields & XFS_ILOG_DEXT) &&
 		    ip->i_d.di_nextents > 0 &&
 		    ip->i_df.if_bytes > 0) {
 			struct xfs_bmbt_rec *p;

 			ASSERT(ip->i_df.if_u1.if_extents != NULL);
 			ASSERT(ip->i_df.if_bytes / sizeof(xfs_bmbt_rec_t) > 0);

 			p = xlog_prepare_iovec(lv, vecp, XLOG_REG_TYPE_IEXT);
 			data_bytes = xfs_iextents_copy(ip, p, XFS_DATA_FORK);
 			xlog_finish_iovec(lv, *vecp, data_bytes);

 			ASSERT(data_bytes <= ip->i_df.if_bytes);

 			ilf->ilf_dsize = data_bytes;
 			ilf->ilf_size++;
 		} else {
 			iip->ili_fields &= ~XFS_ILOG_DEXT;
 		}
 		break;
 	case XFS_DINODE_FMT_BTREE:
 		iip->ili_fields &=
 			~(XFS_ILOG_DDATA | XFS_ILOG_DEXT |
 			  XFS_ILOG_DEV | XFS_ILOG_UUID);

 		if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
 		    ip->i_df.if_broot_bytes > 0) {
 			ASSERT(ip->i_df.if_broot != NULL);
 			xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_IBROOT,
 					ip->i_df.if_broot,
 					ip->i_df.if_broot_bytes);
 			ilf->ilf_dsize = ip->i_df.if_broot_bytes;
 			ilf->ilf_size++;
 		} else {
 			ASSERT(!(iip->ili_fields &
 				 XFS_ILOG_DBROOT));
 			iip->ili_fields &= ~XFS_ILOG_DBROOT;
 		}
 		break;
 	case XFS_DINODE_FMT_LOCAL:
 		iip->ili_fields &=
 			~(XFS_ILOG_DEXT | XFS_ILOG_DBROOT |
 			  XFS_ILOG_DEV | XFS_ILOG_UUID);
 		if ((iip->ili_fields & XFS_ILOG_DDATA) &&
 		    ip->i_df.if_bytes > 0) {
 			/*
 			 * Round i_bytes up to a word boundary.
 			 * The underlying memory is guaranteed to
 			 * to be there by xfs_idata_realloc().
 			 */
 			data_bytes = roundup(ip->i_df.if_bytes, 4);
 			ASSERT(ip->i_df.if_real_bytes == 0 ||
 			       ip->i_df.if_real_bytes == data_bytes);
 			ASSERT(ip->i_df.if_u1.if_data != NULL);
 			ASSERT(ip->i_d.di_size > 0);
 			xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_ILOCAL,
 					ip->i_df.if_u1.if_data, data_bytes);
 			ilf->ilf_dsize = (unsigned)data_bytes;
 			ilf->ilf_size++;
 		} else {
 			iip->ili_fields &= ~XFS_ILOG_DDATA;
 		}
 		break;
 	case XFS_DINODE_FMT_DEV:
 		iip->ili_fields &=
 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
 			  XFS_ILOG_DEXT | XFS_ILOG_UUID);
 		if (iip->ili_fields & XFS_ILOG_DEV)
 			ilf->ilf_u.ilfu_rdev = ip->i_df.if_u2.if_rdev;
 		break;
 	case XFS_DINODE_FMT_UUID:
 		iip->ili_fields &=
 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
 			  XFS_ILOG_DEXT | XFS_ILOG_DEV);
 		if (iip->ili_fields & XFS_ILOG_UUID)
 			ilf->ilf_u.ilfu_uuid = ip->i_df.if_u2.if_uuid;
 		break;
 	default:
 		ASSERT(0);
 		break;
 	}
 }

 STATIC void
 xfs_inode_item_format_attr_fork(
 	struct xfs_inode_log_item *iip,
 	struct xfs_inode_log_format *ilf,
 	struct xfs_log_vec	*lv,
 	struct xfs_log_iovec	**vecp)
 {
 	struct xfs_inode	*ip = iip->ili_inode;
 	size_t			data_bytes;

 	switch (ip->i_d.di_aformat) {
 	case XFS_DINODE_FMT_EXTENTS:
 		iip->ili_fields &=
 			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT);

 		if ((iip->ili_fields & XFS_ILOG_AEXT) &&
 		    ip->i_d.di_anextents > 0 &&
 		    ip->i_afp->if_bytes > 0) {
 			struct xfs_bmbt_rec *p;

 			ASSERT(ip->i_afp->if_bytes / sizeof(xfs_bmbt_rec_t) ==
 				ip->i_d.di_anextents);
 			ASSERT(ip->i_afp->if_u1.if_extents != NULL);

 			p = xlog_prepare_iovec(lv, vecp, XLOG_REG_TYPE_IATTR_EXT);
 			data_bytes = xfs_iextents_copy(ip, p, XFS_ATTR_FORK);
 			xlog_finish_iovec(lv, *vecp, data_bytes);

 			ilf->ilf_asize = data_bytes;
 			ilf->ilf_size++;
 		} else {
 			iip->ili_fields &= ~XFS_ILOG_AEXT;
 		}
 		break;
 	case XFS_DINODE_FMT_BTREE:
 		iip->ili_fields &=
 			~(XFS_ILOG_ADATA | XFS_ILOG_AEXT);

 		if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
 		    ip->i_afp->if_broot_bytes > 0) {
 			ASSERT(ip->i_afp->if_broot != NULL);

 			xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_IATTR_BROOT,
 					ip->i_afp->if_broot,
 					ip->i_afp->if_broot_bytes);
 			ilf->ilf_asize = ip->i_afp->if_broot_bytes;
 			ilf->ilf_size++;
 		} else {
 			iip->ili_fields &= ~XFS_ILOG_ABROOT;
 		}
 		break;
 	case XFS_DINODE_FMT_LOCAL:
 		iip->ili_fields &=
 			~(XFS_ILOG_AEXT | XFS_ILOG_ABROOT);

 		if ((iip->ili_fields & XFS_ILOG_ADATA) &&
 		    ip->i_afp->if_bytes > 0) {
 			/*
 			 * Round i_bytes up to a word boundary.
 			 * The underlying memory is guaranteed to
 			 * to be there by xfs_idata_realloc().
 			 */
 			data_bytes = roundup(ip->i_afp->if_bytes, 4);
 			ASSERT(ip->i_afp->if_real_bytes == 0 ||
 			       ip->i_afp->if_real_bytes == data_bytes);
 			ASSERT(ip->i_afp->if_u1.if_data != NULL);
 			xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_IATTR_LOCAL,
 					ip->i_afp->if_u1.if_data,
 					data_bytes);
 			ilf->ilf_asize = (unsigned)data_bytes;
 			ilf->ilf_size++;
 		} else {
 			iip->ili_fields &= ~XFS_ILOG_ADATA;
 		}
 		break;
 	default:
 		ASSERT(0);
 		break;
 	}
 }

 /*
  * This is called to fill in the vector of log iovecs for the given inode
  * log item.  It fills the first item with an inode log format structure,
  * the second with the on-disk inode structure, and a possible third and/or
  * fourth with the inode data/extents/b-tree root and inode attributes
  * data/extents/b-tree root.
  */
 STATIC void
 xfs_inode_item_format(
 	struct xfs_log_item	*lip,
 	struct xfs_log_vec	*lv)
 {
 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
 	struct xfs_inode	*ip = iip->ili_inode;
 	struct xfs_inode_log_format *ilf;
 	struct xfs_log_iovec	*vecp = NULL;

 	ASSERT(ip->i_d.di_version > 1);

 	ilf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_IFORMAT);
 	ilf->ilf_type = XFS_LI_INODE;
 	ilf->ilf_ino = ip->i_ino;
 	ilf->ilf_blkno = ip->i_imap.im_blkno;
 	ilf->ilf_len = ip->i_imap.im_len;
 	ilf->ilf_boffset = ip->i_imap.im_boffset;
 	ilf->ilf_fields = XFS_ILOG_CORE;
 	ilf->ilf_size = 2; /* format + core */
 	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_inode_log_format));

 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_ICORE,
 			&ip->i_d,
 			xfs_icdinode_size(ip->i_d.di_version));

 	xfs_inode_item_format_data_fork(iip, ilf, lv, &vecp);
 	if (XFS_IFORK_Q(ip)) {
 		xfs_inode_item_format_attr_fork(iip, ilf, lv, &vecp);
 	} else {
 		iip->ili_fields &=
 			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT | XFS_ILOG_AEXT);
 	}

 	/* update the format with the exact fields we actually logged */
 	ilf->ilf_fields |= (iip->ili_fields & ~XFS_ILOG_TIMESTAMP);
 }

 /*
  * This is called to pin the inode associated with the inode log
  * item in memory so it cannot be written out.
  */
 STATIC void
 xfs_inode_item_pin(
 	struct xfs_log_item	*lip)
 {
 	struct xfs_inode	*ip = INODE_ITEM(lip)->ili_inode;

 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));

 	trace_xfs_inode_pin(ip, _RET_IP_);
 	atomic_inc(&ip->i_pincount);
 }


 /*
  * This is called to unpin the inode associated with the inode log
  * item which was previously pinned with a call to xfs_inode_item_pin().
  *
  * Also wake up anyone in xfs_iunpin_wait() if the count goes to 0.
  */
 STATIC void
 xfs_inode_item_unpin(
 	struct xfs_log_item	*lip,
 	int			remove)
 {
 	struct xfs_inode	*ip = INODE_ITEM(lip)->ili_inode;

 	trace_xfs_inode_unpin(ip, _RET_IP_);
 	ASSERT(atomic_read(&ip->i_pincount) > 0);
 	if (atomic_dec_and_test(&ip->i_pincount))
 		wake_up_bit(&ip->i_flags, __XFS_IPINNED_BIT);
 }

 STATIC uint
 xfs_inode_item_push(
 	struct xfs_log_item	*lip,
 	struct list_head	*buffer_list)
 {
 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
 	struct xfs_inode	*ip = iip->ili_inode;
 	struct xfs_buf		*bp = NULL;
 	uint			rval = XFS_ITEM_SUCCESS;
 	int			error;

 	if (xfs_ipincount(ip) > 0)
 		return XFS_ITEM_PINNED;

 	if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED))
 		return XFS_ITEM_LOCKED;

 	/*
 	 * Re-check the pincount now that we stabilized the value by
 	 * taking the ilock.
 	 */
 	if (xfs_ipincount(ip) > 0) {
 		rval = XFS_ITEM_PINNED;
 		goto out_unlock;
 	}

 	/*
 	 * Stale inode items should force out the iclog.
 	 */
 	if (ip->i_flags & XFS_ISTALE) {
 		rval = XFS_ITEM_PINNED;
 		goto out_unlock;
 	}

 	/*
 	 * Someone else is already flushing the inode.  Nothing we can do
 	 * here but wait for the flush to finish and remove the item from
 	 * the AIL.
 	 */
 	if (!xfs_iflock_nowait(ip)) {
 		rval = XFS_ITEM_FLUSHING;
 		goto out_unlock;
 	}

 	ASSERT(iip->ili_fields != 0 || XFS_FORCED_SHUTDOWN(ip->i_mount));
 	ASSERT(iip->ili_logged == 0 || XFS_FORCED_SHUTDOWN(ip->i_mount));

 	spin_unlock(&lip->li_ailp->xa_lock);

 	error = xfs_iflush(ip, &bp);
 	if (!error) {
 		if (!xfs_buf_delwri_queue(bp, buffer_list))
 			rval = XFS_ITEM_FLUSHING;
 		xfs_buf_relse(bp);
 	}

 	spin_lock(&lip->li_ailp->xa_lock);
 out_unlock:
 	xfs_iunlock(ip, XFS_ILOCK_SHARED);
 	return rval;
 }

 /*
  * Unlock the inode associated with the inode log item.
  * Clear the fields of the inode and inode log item that
  * are specific to the current transaction.  If the
  * hold flags is set, do not unlock the inode.
  */
 STATIC void
 xfs_inode_item_unlock(
 	struct xfs_log_item	*lip)
 {
 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
 	struct xfs_inode	*ip = iip->ili_inode;
 	unsigned short		lock_flags;

 	ASSERT(ip->i_itemp != NULL);
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));

 	lock_flags = iip->ili_lock_flags;
 	iip->ili_lock_flags = 0;
 	if (lock_flags)
 		xfs_iunlock(ip, lock_flags);
 }

 /*
  * This is called to find out where the oldest active copy of the inode log
  * item in the on disk log resides now that the last log write of it completed
  * at the given lsn.  Since we always re-log all dirty data in an inode, the
  * latest copy in the on disk log is the only one that matters.  Therefore,
  * simply return the given lsn.
  *
  * If the inode has been marked stale because the cluster is being freed, we
  * don't want to (re-)insert this inode into the AIL. There is a race condition
  * where the cluster buffer may be unpinned before the inode is inserted into
  * the AIL during transaction committed processing. If the buffer is unpinned
  * before the inode item has been committed and inserted, then it is possible
  * for the buffer to be written and IO completes before the inode is inserted
  * into the AIL. In that case, we'd be inserting a clean, stale inode into the
  * AIL which will never get removed. It will, however, get reclaimed which
  * triggers an assert in xfs_inode_free() complaining about freein an inode
  * still in the AIL.
  *
  * To avoid this, just unpin the inode directly and return a LSN of -1 so the
  * transaction committed code knows that it does not need to do any further
  * processing on the item.
  */
 STATIC xfs_lsn_t
 xfs_inode_item_committed(
 	struct xfs_log_item	*lip,
 	xfs_lsn_t		lsn)
 {
 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
 	struct xfs_inode	*ip = iip->ili_inode;

 	if (xfs_iflags_test(ip, XFS_ISTALE)) {
 		xfs_inode_item_unpin(lip, 0);
 		return -1;
 	}
 	return lsn;
 }

 /*
  * XXX rcc - this one really has to do something.  Probably needs
  * to stamp in a new field in the incore inode.
  */
 STATIC void
 xfs_inode_item_committing(
 	struct xfs_log_item	*lip,
 	xfs_lsn_t		lsn)
 {
 	INODE_ITEM(lip)->ili_last_lsn = lsn;
 }

 /*
  * This is the ops vector shared by all buf log items.
  */
 static const struct xfs_item_ops xfs_inode_item_ops = {
 	.iop_size	= xfs_inode_item_size,
 	.iop_format	= xfs_inode_item_format,
 	.iop_pin	= xfs_inode_item_pin,
 	.iop_unpin	= xfs_inode_item_unpin,
 	.iop_unlock	= xfs_inode_item_unlock,
 	.iop_committed	= xfs_inode_item_committed,
 	.iop_push	= xfs_inode_item_push,
 	.iop_committing = xfs_inode_item_committing
 };


 /*
  * Initialize the inode log item for a newly allocated (in-core) inode.
  */
 void
 xfs_inode_item_init(
 	struct xfs_inode	*ip,
 	struct xfs_mount	*mp)
 {
 	struct xfs_inode_log_item *iip;

 	ASSERT(ip->i_itemp == NULL);
 	iip = ip->i_itemp = kmem_zone_zalloc(xfs_ili_zone, KM_SLEEP);

 	iip->ili_inode = ip;
 	xfs_log_item_init(mp, &iip->ili_item, XFS_LI_INODE,
 						&xfs_inode_item_ops);
 }

 /*
  * Free the inode log item and any memory hanging off of it.
  */
 void
 xfs_inode_item_destroy(
 	xfs_inode_t	*ip)
 {
 	kmem_zone_free(xfs_ili_zone, ip->i_itemp);
 }


 /*
  * This is the inode flushing I/O completion routine.  It is called
  * from interrupt level when the buffer containing the inode is
  * flushed to disk.  It is responsible for removing the inode item
  * from the AIL if it has not been re-logged, and unlocking the inode's
  * flush lock.
  *
  * To reduce AIL lock traffic as much as possible, we scan the buffer log item
  * list for other inodes that will run this function. We remove them from the
  * buffer list so we can process all the inode IO completions in one AIL lock
  * traversal.
  */
 void
 xfs_iflush_done(
 	struct xfs_buf		*bp,
 	struct xfs_log_item	*lip)
 {
 	struct xfs_inode_log_item *iip;
 	struct xfs_log_item	*blip;
 	struct xfs_log_item	*next;
 	struct xfs_log_item	*prev;
 	struct xfs_ail		*ailp = lip->li_ailp;
 	int			need_ail = 0;

 	/*
 	 * Scan the buffer IO completions for other inodes being completed and
 	 * attach them to the current inode log item.
 	 */
 	blip = bp->b_fspriv;
 	prev = NULL;
 	while (blip != NULL) {
 		if (blip->li_cb != xfs_iflush_done) {
 			prev = blip;
 			blip = blip->li_bio_list;
 			continue;
 		}

 		/* remove from list */
 		next = blip->li_bio_list;
 		if (!prev) {
 			bp->b_fspriv = next;
 		} else {
 			prev->li_bio_list = next;
 		}

 		/* add to current list */
 		blip->li_bio_list = lip->li_bio_list;
 		lip->li_bio_list = blip;

 		/*
 		 * while we have the item, do the unlocked check for needing
 		 * the AIL lock.
 		 */
 		iip = INODE_ITEM(blip);
 		if (iip->ili_logged && blip->li_lsn == iip->ili_flush_lsn)
 			need_ail++;

 		blip = next;
 	}

 	/* make sure we capture the state of the initial inode. */
 	iip = INODE_ITEM(lip);
 	if (iip->ili_logged && lip->li_lsn == iip->ili_flush_lsn)
 		need_ail++;

 	/*
 	 * We only want to pull the item from the AIL if it is
 	 * actually there and its location in the log has not
 	 * changed since we started the flush.  Thus, we only bother
 	 * if the ili_logged flag is set and the inode's lsn has not
 	 * changed.  First we check the lsn outside
 	 * the lock since it's cheaper, and then we recheck while
 	 * holding the lock before removing the inode from the AIL.
 	 */
 	if (need_ail) {
 		struct xfs_log_item *log_items[need_ail];
 		int i = 0;
 		spin_lock(&ailp->xa_lock);
 		for (blip = lip; blip; blip = blip->li_bio_list) {
 			iip = INODE_ITEM(blip);
 			if (iip->ili_logged &&
 			    blip->li_lsn == iip->ili_flush_lsn) {
 				log_items[i++] = blip;
 			}
 			ASSERT(i <= need_ail);
 		}
 		/* xfs_trans_ail_delete_bulk() drops the AIL lock. */
 		xfs_trans_ail_delete_bulk(ailp, log_items, i,
 					  SHUTDOWN_CORRUPT_INCORE);
 	}


 	/*
 	 * clean up and unlock the flush lock now we are done. We can clear the
 	 * ili_last_fields bits now that we know that the data corresponding to
 	 * them is safely on disk.
 	 */
 	for (blip = lip; blip; blip = next) {
 		next = blip->li_bio_list;
 		blip->li_bio_list = NULL;

 		iip = INODE_ITEM(blip);
 		iip->ili_logged = 0;
 		iip->ili_last_fields = 0;
 		xfs_ifunlock(iip->ili_inode);
 	}
 }

 /*
  * This is the inode flushing abort routine.  It is called from xfs_iflush when
  * the filesystem is shutting down to clean up the inode state.  It is
  * responsible for removing the inode item from the AIL if it has not been
  * re-logged, and unlocking the inode's flush lock.
  */
 void
 xfs_iflush_abort(
 	xfs_inode_t		*ip,
 	bool			stale)
 {
 	xfs_inode_log_item_t	*iip = ip->i_itemp;

 	if (iip) {
 		if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
 			xfs_trans_ail_remove(&iip->ili_item,
 					     stale ? SHUTDOWN_LOG_IO_ERROR :
 						     SHUTDOWN_CORRUPT_INCORE);
 		}
 		iip->ili_logged = 0;
 		/*
 		 * Clear the ili_last_fields bits now that we know that the
 		 * data corresponding to them is safely on disk.
 		 */
 		iip->ili_last_fields = 0;
 		/*
 		 * Clear the inode logging fields so no more flushes are
 		 * attempted.
 		 */
 		iip->ili_fields = 0;
 	}
 	/*
 	 * Release the inode's flush lock since we're done with it.
 	 */
 	xfs_ifunlock(ip);
 }

 void
 xfs_istale_done(
 	struct xfs_buf		*bp,
 	struct xfs_log_item	*lip)
 {
 	xfs_iflush_abort(INODE_ITEM(lip)->ili_inode, true);
 }

 /*
  * convert an xfs_inode_log_format struct from either 32 or 64 bit versions
  * (which can have different field alignments) to the native version
  */
 int
 xfs_inode_item_format_convert(
 	xfs_log_iovec_t		*buf,
 	xfs_inode_log_format_t	*in_f)
 {
 	if (buf->i_len == sizeof(xfs_inode_log_format_32_t)) {
 		xfs_inode_log_format_32_t *in_f32 = buf->i_addr;

 		in_f->ilf_type = in_f32->ilf_type;
 		in_f->ilf_size = in_f32->ilf_size;
 		in_f->ilf_fields = in_f32->ilf_fields;
 		in_f->ilf_asize = in_f32->ilf_asize;
 		in_f->ilf_dsize = in_f32->ilf_dsize;
 		in_f->ilf_ino = in_f32->ilf_ino;
 		/* copy biggest field of ilf_u */
 		memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
 		       in_f32->ilf_u.ilfu_uuid.__u_bits,
 		       sizeof(uuid_t));
 		in_f->ilf_blkno = in_f32->ilf_blkno;
 		in_f->ilf_len = in_f32->ilf_len;
 		in_f->ilf_boffset = in_f32->ilf_boffset;
 		return 0;
 	} else if (buf->i_len == sizeof(xfs_inode_log_format_64_t)){
 		xfs_inode_log_format_64_t *in_f64 = buf->i_addr;

 		in_f->ilf_type = in_f64->ilf_type;
 		in_f->ilf_size = in_f64->ilf_size;
 		in_f->ilf_fields = in_f64->ilf_fields;
 		in_f->ilf_asize = in_f64->ilf_asize;
 		in_f->ilf_dsize = in_f64->ilf_dsize;
 		in_f->ilf_ino = in_f64->ilf_ino;
 		/* copy biggest field of ilf_u */
 		memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
 		       in_f64->ilf_u.ilfu_uuid.__u_bits,
 		       sizeof(uuid_t));
 		in_f->ilf_blkno = in_f64->ilf_blkno;
 		in_f->ilf_len = in_f64->ilf_len;
 		in_f->ilf_boffset = in_f64->ilf_boffset;
 		return 0;
 	}
 	return -EFSCORRUPTED;
 }
	/*
	* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
	* All Rights Reserved.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms 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. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*/
	#include "xfs.h"
	#include "xfs_fs.h"
	#include "xfs_format.h"
	#include "xfs_log_format.h"
	#include "xfs_trans_resv.h"
	#include "xfs_mount.h"
	#include "xfs_inode.h"
	#include "xfs_trans.h"
	#include "xfs_inode_item.h"
	#include "xfs_error.h"
	#include "xfs_trace.h"
	#include "xfs_trans_priv.h"
	#include "xfs_log.h"


	kmem_zone_t xfs_ili_zone; / inode log item zone */

	static inline struct xfs_inode_log_item INODE_ITEM(struct xfs_log_item lip)
	{
	return container_of(lip, struct xfs_inode_log_item, ili_item);
	}

	STATIC void
	xfs_inode_item_data_fork_size(
	struct xfs_inode_log_item *iip,
	int *nvecs,
	int *nbytes)
	{
	struct xfs_inode *ip = iip->ili_inode;

	switch (ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
	if ((iip->ili_fields & XFS_ILOG_DEXT) &&
	ip->i_d.di_nextents > 0 &&
	ip->i_df.if_bytes > 0) {
	/* worst case, doesn't subtract delalloc extents */
	*nbytes += XFS_IFORK_DSIZE(ip);
	*nvecs += 1;
	}
	break;
	case XFS_DINODE_FMT_BTREE:
	if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
	ip->i_df.if_broot_bytes > 0) {
	*nbytes += ip->i_df.if_broot_bytes;
	*nvecs += 1;
	}
	break;
	case XFS_DINODE_FMT_LOCAL:
	if ((iip->ili_fields & XFS_ILOG_DDATA) &&
	ip->i_df.if_bytes > 0) {
	*nbytes += roundup(ip->i_df.if_bytes, 4);
	*nvecs += 1;
	}
	break;

	case XFS_DINODE_FMT_DEV:
	case XFS_DINODE_FMT_UUID:
	break;
	default:
	ASSERT(0);
	break;
	}
	}

	STATIC void
	xfs_inode_item_attr_fork_size(
	struct xfs_inode_log_item *iip,
	int *nvecs,
	int *nbytes)
	{
	struct xfs_inode *ip = iip->ili_inode;

	switch (ip->i_d.di_aformat) {
	case XFS_DINODE_FMT_EXTENTS:
	if ((iip->ili_fields & XFS_ILOG_AEXT) &&
	ip->i_d.di_anextents > 0 &&
	ip->i_afp->if_bytes > 0) {
	/* worst case, doesn't subtract unused space */
	*nbytes += XFS_IFORK_ASIZE(ip);
	*nvecs += 1;
	}
	break;
	case XFS_DINODE_FMT_BTREE:
	if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
	ip->i_afp->if_broot_bytes > 0) {
	*nbytes += ip->i_afp->if_broot_bytes;
	*nvecs += 1;
	}
	break;
	case XFS_DINODE_FMT_LOCAL:
	if ((iip->ili_fields & XFS_ILOG_ADATA) &&
	ip->i_afp->if_bytes > 0) {
	*nbytes += roundup(ip->i_afp->if_bytes, 4);
	*nvecs += 1;
	}
	break;
	default:
	ASSERT(0);
	break;
	}
	}

	/*
	* This returns the number of iovecs needed to log the given inode item.
	*
	* We need one iovec for the inode log format structure, one for the
	* inode core, and possibly one for the inode data/extents/b-tree root
	* and one for the inode attribute data/extents/b-tree root.
	*/
	STATIC void
	xfs_inode_item_size(
	struct xfs_log_item *lip,
	int *nvecs,
	int *nbytes)
	{
	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
	struct xfs_inode *ip = iip->ili_inode;

	*nvecs += 2;
	*nbytes += sizeof(struct xfs_inode_log_format) +
	xfs_icdinode_size(ip->i_d.di_version);

	xfs_inode_item_data_fork_size(iip, nvecs, nbytes);
	if (XFS_IFORK_Q(ip))
	xfs_inode_item_attr_fork_size(iip, nvecs, nbytes);
	}

	STATIC void
	xfs_inode_item_format_data_fork(
	struct xfs_inode_log_item *iip,
	struct xfs_inode_log_format *ilf,
	struct xfs_log_vec *lv,
	struct xfs_log_iovec **vecp)
	{
	struct xfs_inode *ip = iip->ili_inode;
	size_t data_bytes;

	switch (ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
	iip->ili_fields &=
	~(XFS_ILOG_DDATA \| XFS_ILOG_DBROOT \|
	XFS_ILOG_DEV \| XFS_ILOG_UUID);

	if ((iip->ili_fields & XFS_ILOG_DEXT) &&
	ip->i_d.di_nextents > 0 &&
	ip->i_df.if_bytes > 0) {
	struct xfs_bmbt_rec *p;

	ASSERT(ip->i_df.if_u1.if_extents != NULL);
	ASSERT(ip->i_df.if_bytes / sizeof(xfs_bmbt_rec_t) > 0);

	p = xlog_prepare_iovec(lv, vecp, XLOG_REG_TYPE_IEXT);
	data_bytes = xfs_iextents_copy(ip, p, XFS_DATA_FORK);
	xlog_finish_iovec(lv, *vecp, data_bytes);

	ASSERT(data_bytes <= ip->i_df.if_bytes);

	ilf->ilf_dsize = data_bytes;
	ilf->ilf_size++;
	} else {
	iip->ili_fields &= ~XFS_ILOG_DEXT;
	}
	break;
	case XFS_DINODE_FMT_BTREE:
	iip->ili_fields &=
	~(XFS_ILOG_DDATA \| XFS_ILOG_DEXT \|
	XFS_ILOG_DEV \| XFS_ILOG_UUID);

	if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
	ip->i_df.if_broot_bytes > 0) {
	ASSERT(ip->i_df.if_broot != NULL);
	xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_IBROOT,
	ip->i_df.if_broot,
	ip->i_df.if_broot_bytes);
	ilf->ilf_dsize = ip->i_df.if_broot_bytes;
	ilf->ilf_size++;
	} else {
	ASSERT(!(iip->ili_fields &
	XFS_ILOG_DBROOT));
	iip->ili_fields &= ~XFS_ILOG_DBROOT;
	}
	break;
	case XFS_DINODE_FMT_LOCAL:
	iip->ili_fields &=
	~(XFS_ILOG_DEXT \| XFS_ILOG_DBROOT \|
	XFS_ILOG_DEV \| XFS_ILOG_UUID);
	if ((iip->ili_fields & XFS_ILOG_DDATA) &&
	ip->i_df.if_bytes > 0) {
	/*
	* Round i_bytes up to a word boundary.
	* The underlying memory is guaranteed to
	* to be there by xfs_idata_realloc().
	*/
	data_bytes = roundup(ip->i_df.if_bytes, 4);
	ASSERT(ip->i_df.if_real_bytes == 0 \|\|
	ip->i_df.if_real_bytes == data_bytes);
	ASSERT(ip->i_df.if_u1.if_data != NULL);
	ASSERT(ip->i_d.di_size > 0);
	xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_ILOCAL,
	ip->i_df.if_u1.if_data, data_bytes);
	ilf->ilf_dsize = (unsigned)data_bytes;
	ilf->ilf_size++;
	} else {
	iip->ili_fields &= ~XFS_ILOG_DDATA;
	}
	break;
	case XFS_DINODE_FMT_DEV:
	iip->ili_fields &=
	~(XFS_ILOG_DDATA \| XFS_ILOG_DBROOT \|
	XFS_ILOG_DEXT \| XFS_ILOG_UUID);
	if (iip->ili_fields & XFS_ILOG_DEV)
	ilf->ilf_u.ilfu_rdev = ip->i_df.if_u2.if_rdev;
	break;
	case XFS_DINODE_FMT_UUID:
	iip->ili_fields &=
	~(XFS_ILOG_DDATA \| XFS_ILOG_DBROOT \|
	XFS_ILOG_DEXT \| XFS_ILOG_DEV);
	if (iip->ili_fields & XFS_ILOG_UUID)
	ilf->ilf_u.ilfu_uuid = ip->i_df.if_u2.if_uuid;
	break;
	default:
	ASSERT(0);
	break;
	}
	}

	STATIC void
	xfs_inode_item_format_attr_fork(
	struct xfs_inode_log_item *iip,
	struct xfs_inode_log_format *ilf,
	struct xfs_log_vec *lv,
	struct xfs_log_iovec **vecp)
	{
	struct xfs_inode *ip = iip->ili_inode;
	size_t data_bytes;

	switch (ip->i_d.di_aformat) {
	case XFS_DINODE_FMT_EXTENTS:
	iip->ili_fields &=
	~(XFS_ILOG_ADATA \| XFS_ILOG_ABROOT);

	if ((iip->ili_fields & XFS_ILOG_AEXT) &&
	ip->i_d.di_anextents > 0 &&
	ip->i_afp->if_bytes > 0) {
	struct xfs_bmbt_rec *p;

	ASSERT(ip->i_afp->if_bytes / sizeof(xfs_bmbt_rec_t) ==
	ip->i_d.di_anextents);
	ASSERT(ip->i_afp->if_u1.if_extents != NULL);

	p = xlog_prepare_iovec(lv, vecp, XLOG_REG_TYPE_IATTR_EXT);
	data_bytes = xfs_iextents_copy(ip, p, XFS_ATTR_FORK);
	xlog_finish_iovec(lv, *vecp, data_bytes);

	ilf->ilf_asize = data_bytes;
	ilf->ilf_size++;
	} else {
	iip->ili_fields &= ~XFS_ILOG_AEXT;
	}
	break;
	case XFS_DINODE_FMT_BTREE:
	iip->ili_fields &=
	~(XFS_ILOG_ADATA \| XFS_ILOG_AEXT);

	if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
	ip->i_afp->if_broot_bytes > 0) {
	ASSERT(ip->i_afp->if_broot != NULL);

	xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_IATTR_BROOT,
	ip->i_afp->if_broot,
	ip->i_afp->if_broot_bytes);
	ilf->ilf_asize = ip->i_afp->if_broot_bytes;
	ilf->ilf_size++;
	} else {
	iip->ili_fields &= ~XFS_ILOG_ABROOT;
	}
	break;
	case XFS_DINODE_FMT_LOCAL:
	iip->ili_fields &=
	~(XFS_ILOG_AEXT \| XFS_ILOG_ABROOT);

	if ((iip->ili_fields & XFS_ILOG_ADATA) &&
	ip->i_afp->if_bytes > 0) {
	/*
	* Round i_bytes up to a word boundary.
	* The underlying memory is guaranteed to
	* to be there by xfs_idata_realloc().
	*/
	data_bytes = roundup(ip->i_afp->if_bytes, 4);
	ASSERT(ip->i_afp->if_real_bytes == 0 \|\|
	ip->i_afp->if_real_bytes == data_bytes);
	ASSERT(ip->i_afp->if_u1.if_data != NULL);
	xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_IATTR_LOCAL,
	ip->i_afp->if_u1.if_data,
	data_bytes);
	ilf->ilf_asize = (unsigned)data_bytes;
	ilf->ilf_size++;
	} else {
	iip->ili_fields &= ~XFS_ILOG_ADATA;
	}
	break;
	default:
	ASSERT(0);
	break;
	}
	}

	/*
	* This is called to fill in the vector of log iovecs for the given inode
	* log item. It fills the first item with an inode log format structure,
	* the second with the on-disk inode structure, and a possible third and/or
	* fourth with the inode data/extents/b-tree root and inode attributes
	* data/extents/b-tree root.
	*/
	STATIC void
	xfs_inode_item_format(
	struct xfs_log_item *lip,
	struct xfs_log_vec *lv)
	{
	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
	struct xfs_inode *ip = iip->ili_inode;
	struct xfs_inode_log_format *ilf;
	struct xfs_log_iovec *vecp = NULL;

	ASSERT(ip->i_d.di_version > 1);

	ilf = xlog_prepare_iovec(lv, &vecp, XLOG_REG_TYPE_IFORMAT);
	ilf->ilf_type = XFS_LI_INODE;
	ilf->ilf_ino = ip->i_ino;
	ilf->ilf_blkno = ip->i_imap.im_blkno;
	ilf->ilf_len = ip->i_imap.im_len;
	ilf->ilf_boffset = ip->i_imap.im_boffset;
	ilf->ilf_fields = XFS_ILOG_CORE;
	ilf->ilf_size = 2; /* format + core */
	xlog_finish_iovec(lv, vecp, sizeof(struct xfs_inode_log_format));

	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_ICORE,
	&ip->i_d,
	xfs_icdinode_size(ip->i_d.di_version));

	xfs_inode_item_format_data_fork(iip, ilf, lv, &vecp);
	if (XFS_IFORK_Q(ip)) {
	xfs_inode_item_format_attr_fork(iip, ilf, lv, &vecp);
	} else {
	iip->ili_fields &=
	~(XFS_ILOG_ADATA \| XFS_ILOG_ABROOT \| XFS_ILOG_AEXT);
	}

	/* update the format with the exact fields we actually logged */
	ilf->ilf_fields \|= (iip->ili_fields & ~XFS_ILOG_TIMESTAMP);
	}

	/*
	* This is called to pin the inode associated with the inode log
	* item in memory so it cannot be written out.
	*/
	STATIC void
	xfs_inode_item_pin(
	struct xfs_log_item *lip)
	{
	struct xfs_inode *ip = INODE_ITEM(lip)->ili_inode;

	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));

	trace_xfs_inode_pin(ip, _RET_IP_);
	atomic_inc(&ip->i_pincount);
	}


	/*
	* This is called to unpin the inode associated with the inode log
	* item which was previously pinned with a call to xfs_inode_item_pin().
	*
	* Also wake up anyone in xfs_iunpin_wait() if the count goes to 0.
	*/
	STATIC void
	xfs_inode_item_unpin(
	struct xfs_log_item *lip,
	int remove)
	{
	struct xfs_inode *ip = INODE_ITEM(lip)->ili_inode;

	trace_xfs_inode_unpin(ip, _RET_IP_);
	ASSERT(atomic_read(&ip->i_pincount) > 0);
	if (atomic_dec_and_test(&ip->i_pincount))
	wake_up_bit(&ip->i_flags, __XFS_IPINNED_BIT);
	}

	STATIC uint
	xfs_inode_item_push(
	struct xfs_log_item *lip,
	struct list_head *buffer_list)
	{
	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
	struct xfs_inode *ip = iip->ili_inode;
	struct xfs_buf *bp = NULL;
	uint rval = XFS_ITEM_SUCCESS;
	int error;

	if (xfs_ipincount(ip) > 0)
	return XFS_ITEM_PINNED;

	if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED))
	return XFS_ITEM_LOCKED;

	/*
	* Re-check the pincount now that we stabilized the value by
	* taking the ilock.
	*/
	if (xfs_ipincount(ip) > 0) {
	rval = XFS_ITEM_PINNED;
	goto out_unlock;
	}

	/*
	* Stale inode items should force out the iclog.
	*/
	if (ip->i_flags & XFS_ISTALE) {
	rval = XFS_ITEM_PINNED;
	goto out_unlock;
	}

	/*
	* Someone else is already flushing the inode. Nothing we can do
	* here but wait for the flush to finish and remove the item from
	* the AIL.
	*/
	if (!xfs_iflock_nowait(ip)) {
	rval = XFS_ITEM_FLUSHING;
	goto out_unlock;
	}

	ASSERT(iip->ili_fields != 0 \|\| XFS_FORCED_SHUTDOWN(ip->i_mount));
	ASSERT(iip->ili_logged == 0 \|\| XFS_FORCED_SHUTDOWN(ip->i_mount));

	spin_unlock(&lip->li_ailp->xa_lock);

	error = xfs_iflush(ip, &bp);
	if (!error) {
	if (!xfs_buf_delwri_queue(bp, buffer_list))
	rval = XFS_ITEM_FLUSHING;
	xfs_buf_relse(bp);
	}

	spin_lock(&lip->li_ailp->xa_lock);
	out_unlock:
	xfs_iunlock(ip, XFS_ILOCK_SHARED);
	return rval;
	}

	/*
	* Unlock the inode associated with the inode log item.
	* Clear the fields of the inode and inode log item that
	* are specific to the current transaction. If the
	* hold flags is set, do not unlock the inode.
	*/
	STATIC void
	xfs_inode_item_unlock(
	struct xfs_log_item *lip)
	{
	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
	struct xfs_inode *ip = iip->ili_inode;
	unsigned short lock_flags;

	ASSERT(ip->i_itemp != NULL);
	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));

	lock_flags = iip->ili_lock_flags;
	iip->ili_lock_flags = 0;
	if (lock_flags)
	xfs_iunlock(ip, lock_flags);
	}

	/*
	* This is called to find out where the oldest active copy of the inode log
	* item in the on disk log resides now that the last log write of it completed
	* at the given lsn. Since we always re-log all dirty data in an inode, the
	* latest copy in the on disk log is the only one that matters. Therefore,
	* simply return the given lsn.
	*
	* If the inode has been marked stale because the cluster is being freed, we
	* don't want to (re-)insert this inode into the AIL. There is a race condition
	* where the cluster buffer may be unpinned before the inode is inserted into
	* the AIL during transaction committed processing. If the buffer is unpinned
	* before the inode item has been committed and inserted, then it is possible
	* for the buffer to be written and IO completes before the inode is inserted
	* into the AIL. In that case, we'd be inserting a clean, stale inode into the
	* AIL which will never get removed. It will, however, get reclaimed which
	* triggers an assert in xfs_inode_free() complaining about freein an inode
	* still in the AIL.
	*
	* To avoid this, just unpin the inode directly and return a LSN of -1 so the
	* transaction committed code knows that it does not need to do any further
	* processing on the item.
	*/
	STATIC xfs_lsn_t
	xfs_inode_item_committed(
	struct xfs_log_item *lip,
	xfs_lsn_t lsn)
	{
	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
	struct xfs_inode *ip = iip->ili_inode;

	if (xfs_iflags_test(ip, XFS_ISTALE)) {
	xfs_inode_item_unpin(lip, 0);
	return -1;
	}
	return lsn;
	}

	/*
	* XXX rcc - this one really has to do something. Probably needs
	* to stamp in a new field in the incore inode.
	*/
	STATIC void
	xfs_inode_item_committing(
	struct xfs_log_item *lip,
	xfs_lsn_t lsn)
	{
	INODE_ITEM(lip)->ili_last_lsn = lsn;
	}

	/*
	* This is the ops vector shared by all buf log items.
	*/
	static const struct xfs_item_ops xfs_inode_item_ops = {
	.iop_size = xfs_inode_item_size,
	.iop_format = xfs_inode_item_format,
	.iop_pin = xfs_inode_item_pin,
	.iop_unpin = xfs_inode_item_unpin,
	.iop_unlock = xfs_inode_item_unlock,
	.iop_committed = xfs_inode_item_committed,
	.iop_push = xfs_inode_item_push,
	.iop_committing = xfs_inode_item_committing
	};


	/*
	* Initialize the inode log item for a newly allocated (in-core) inode.
	*/
	void
	xfs_inode_item_init(
	struct xfs_inode *ip,
	struct xfs_mount *mp)
	{
	struct xfs_inode_log_item *iip;

	ASSERT(ip->i_itemp == NULL);
	iip = ip->i_itemp = kmem_zone_zalloc(xfs_ili_zone, KM_SLEEP);

	iip->ili_inode = ip;
	xfs_log_item_init(mp, &iip->ili_item, XFS_LI_INODE,
	&xfs_inode_item_ops);
	}

	/*
	* Free the inode log item and any memory hanging off of it.
	*/
	void
	xfs_inode_item_destroy(
	xfs_inode_t *ip)
	{
	kmem_zone_free(xfs_ili_zone, ip->i_itemp);
	}


	/*
	* This is the inode flushing I/O completion routine. It is called
	* from interrupt level when the buffer containing the inode is
	* flushed to disk. It is responsible for removing the inode item
	* from the AIL if it has not been re-logged, and unlocking the inode's
	* flush lock.
	*
	* To reduce AIL lock traffic as much as possible, we scan the buffer log item
	* list for other inodes that will run this function. We remove them from the
	* buffer list so we can process all the inode IO completions in one AIL lock
	* traversal.
	*/
	void
	xfs_iflush_done(
	struct xfs_buf *bp,
	struct xfs_log_item *lip)
	{
	struct xfs_inode_log_item *iip;
	struct xfs_log_item *blip;
	struct xfs_log_item *next;
	struct xfs_log_item *prev;
	struct xfs_ail *ailp = lip->li_ailp;
	int need_ail = 0;

	/*
	* Scan the buffer IO completions for other inodes being completed and
	* attach them to the current inode log item.
	*/
	blip = bp->b_fspriv;
	prev = NULL;
	while (blip != NULL) {
	if (blip->li_cb != xfs_iflush_done) {
	prev = blip;
	blip = blip->li_bio_list;
	continue;
	}

	/* remove from list */
	next = blip->li_bio_list;
	if (!prev) {
	bp->b_fspriv = next;
	} else {
	prev->li_bio_list = next;
	}

	/* add to current list */
	blip->li_bio_list = lip->li_bio_list;
	lip->li_bio_list = blip;

	/*
	* while we have the item, do the unlocked check for needing
	* the AIL lock.
	*/
	iip = INODE_ITEM(blip);
	if (iip->ili_logged && blip->li_lsn == iip->ili_flush_lsn)
	need_ail++;

	blip = next;
	}

	/* make sure we capture the state of the initial inode. */
	iip = INODE_ITEM(lip);
	if (iip->ili_logged && lip->li_lsn == iip->ili_flush_lsn)
	need_ail++;

	/*
	* We only want to pull the item from the AIL if it is
	* actually there and its location in the log has not
	* changed since we started the flush. Thus, we only bother
	* if the ili_logged flag is set and the inode's lsn has not
	* changed. First we check the lsn outside
	* the lock since it's cheaper, and then we recheck while
	* holding the lock before removing the inode from the AIL.
	*/
	if (need_ail) {
	struct xfs_log_item *log_items[need_ail];
	int i = 0;
	spin_lock(&ailp->xa_lock);
	for (blip = lip; blip; blip = blip->li_bio_list) {
	iip = INODE_ITEM(blip);
	if (iip->ili_logged &&
	blip->li_lsn == iip->ili_flush_lsn) {
	log_items[i++] = blip;
	}
	ASSERT(i <= need_ail);
	}
	/* xfs_trans_ail_delete_bulk() drops the AIL lock. */
	xfs_trans_ail_delete_bulk(ailp, log_items, i,
	SHUTDOWN_CORRUPT_INCORE);
	}


	/*
	* clean up and unlock the flush lock now we are done. We can clear the
	* ili_last_fields bits now that we know that the data corresponding to
	* them is safely on disk.
	*/
	for (blip = lip; blip; blip = next) {
	next = blip->li_bio_list;
	blip->li_bio_list = NULL;

	iip = INODE_ITEM(blip);
	iip->ili_logged = 0;
	iip->ili_last_fields = 0;
	xfs_ifunlock(iip->ili_inode);
	}
	}

	/*
	* This is the inode flushing abort routine. It is called from xfs_iflush when
	* the filesystem is shutting down to clean up the inode state. It is
	* responsible for removing the inode item from the AIL if it has not been
	* re-logged, and unlocking the inode's flush lock.
	*/
	void
	xfs_iflush_abort(
	xfs_inode_t *ip,
	bool stale)
	{
	xfs_inode_log_item_t *iip = ip->i_itemp;

	if (iip) {
	if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
	xfs_trans_ail_remove(&iip->ili_item,
	stale ? SHUTDOWN_LOG_IO_ERROR :
	SHUTDOWN_CORRUPT_INCORE);
	}
	iip->ili_logged = 0;
	/*
	* Clear the ili_last_fields bits now that we know that the
	* data corresponding to them is safely on disk.
	*/
	iip->ili_last_fields = 0;
	/*
	* Clear the inode logging fields so no more flushes are
	* attempted.
	*/
	iip->ili_fields = 0;
	}
	/*
	* Release the inode's flush lock since we're done with it.
	*/
	xfs_ifunlock(ip);
	}

	void
	xfs_istale_done(
	struct xfs_buf *bp,
	struct xfs_log_item *lip)
	{
	xfs_iflush_abort(INODE_ITEM(lip)->ili_inode, true);
	}

	/*
	* convert an xfs_inode_log_format struct from either 32 or 64 bit versions
	* (which can have different field alignments) to the native version
	*/
	int
	xfs_inode_item_format_convert(
	xfs_log_iovec_t *buf,
	xfs_inode_log_format_t *in_f)
	{
	if (buf->i_len == sizeof(xfs_inode_log_format_32_t)) {
	xfs_inode_log_format_32_t *in_f32 = buf->i_addr;

	in_f->ilf_type = in_f32->ilf_type;
	in_f->ilf_size = in_f32->ilf_size;
	in_f->ilf_fields = in_f32->ilf_fields;
	in_f->ilf_asize = in_f32->ilf_asize;
	in_f->ilf_dsize = in_f32->ilf_dsize;
	in_f->ilf_ino = in_f32->ilf_ino;
	/* copy biggest field of ilf_u */
	memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
	in_f32->ilf_u.ilfu_uuid.__u_bits,
	sizeof(uuid_t));
	in_f->ilf_blkno = in_f32->ilf_blkno;
	in_f->ilf_len = in_f32->ilf_len;
	in_f->ilf_boffset = in_f32->ilf_boffset;
	return 0;
	} else if (buf->i_len == sizeof(xfs_inode_log_format_64_t)){
	xfs_inode_log_format_64_t *in_f64 = buf->i_addr;

	in_f->ilf_type = in_f64->ilf_type;
	in_f->ilf_size = in_f64->ilf_size;
	in_f->ilf_fields = in_f64->ilf_fields;
	in_f->ilf_asize = in_f64->ilf_asize;
	in_f->ilf_dsize = in_f64->ilf_dsize;
	in_f->ilf_ino = in_f64->ilf_ino;
	/* copy biggest field of ilf_u */
	memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
	in_f64->ilf_u.ilfu_uuid.__u_bits,
	sizeof(uuid_t));
	in_f->ilf_blkno = in_f64->ilf_blkno;
	in_f->ilf_len = in_f64->ilf_len;
	in_f->ilf_boffset = in_f64->ilf_boffset;
	return 0;
	}
	return -EFSCORRUPTED;
	}