Return to xfs_inode_item.c CVS log

Up to [Development] / xfs-linux

389343 : AIL lock held for too long.
Split the tasks of IOP_PUSH into IOP_PUSHBUF and IOP_PUSH.
This way we don't have to call into the bufcache holding
the AIL lock, among other good things. Now we delay looking for
the inode buffer in the bufcache until the pushbuf routine.

#ident "$Revision: 1.66 $"

/*
 * This file contains the implementation of the xfs_inode_log_item.
 * It contains the item operations used to manipulate the inode log
 * items as well as utility routines used by the inode specific
 * transaction routines.
 */


#ifdef SIM
#define _KERNEL 1
#endif
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/uuid.h>
#include <sys/grio.h>
#include <sys/debug.h>
#ifdef SIM
#undef _KERNEL
#include <bstring.h>
#else
#include <sys/systm.h>
#endif
#include <sys/kmem.h>
#include <sys/kabi.h>
#include "xfs_macros.h"
#include "xfs_types.h"
#include "xfs_inum.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_buf_item.h"
#include "xfs_sb.h"
#include "xfs_mount.h"
#include "xfs_trans_priv.h"
#include "xfs_ag.h"
#include "xfs_alloc_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_attr_sf.h"
#include "xfs_dir_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode_item.h"
#include "xfs_inode.h"
#ifdef SIM
#include "sim.h"
#endif

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

/*
 * 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 uint
xfs_inode_item_size(
	xfs_inode_log_item_t	*iip)
{
	uint		nvecs;
	xfs_inode_t	*ip;

	ip = iip->ili_inode;
	nvecs = 2;

	/*
	 * Only log the data/extents/b-tree root if there is something
	 * left to log.
	 */
	iip->ili_format.ilf_fields |= XFS_ILOG_CORE;

	switch (ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
			  XFS_ILOG_DEV | XFS_ILOG_UUID);
		if ((iip->ili_format.ilf_fields & XFS_ILOG_DEXT) &&
		    (ip->i_d.di_nextents > 0) &&
		    (ip->i_df.if_bytes > 0)) {
			ASSERT(ip->i_df.if_u1.if_extents != NULL);
			nvecs++;
		} else {
			iip->ili_format.ilf_fields &= ~XFS_ILOG_DEXT;
		}
		break;

	case XFS_DINODE_FMT_BTREE:
		ASSERT(ip->i_df.if_ext_max ==
		       XFS_IFORK_DSIZE(ip) / sizeof(xfs_bmbt_rec_t));
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_DDATA | XFS_ILOG_DEXT |
			  XFS_ILOG_DEV | XFS_ILOG_UUID);
		if ((iip->ili_format.ilf_fields & XFS_ILOG_DBROOT) &&
		    (ip->i_df.if_broot_bytes > 0)) {
			ASSERT(ip->i_df.if_broot != NULL);
			nvecs++;
		} else {
			ASSERT(!(iip->ili_format.ilf_fields &
				 XFS_ILOG_DBROOT));
#ifdef XFS_TRANS_DEBUG
			if (iip->ili_root_size > 0) {
				ASSERT(iip->ili_root_size ==
				       ip->i_df.if_broot_bytes);
				ASSERT(bcmp(iip->ili_orig_root,
					    ip->i_df.if_broot,
					    iip->ili_root_size) == 0);
			} else {
				ASSERT(ip->i_df.if_broot_bytes == 0);
			}
#endif
			iip->ili_format.ilf_fields &= ~XFS_ILOG_DBROOT;
		}
		break;

	case XFS_DINODE_FMT_LOCAL:
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_DEXT | XFS_ILOG_DBROOT |
			  XFS_ILOG_DEV | XFS_ILOG_UUID);
		if ((iip->ili_format.ilf_fields & XFS_ILOG_DDATA) &&
		    (ip->i_df.if_bytes > 0)) {
			ASSERT(ip->i_df.if_u1.if_data != NULL);
			ASSERT(ip->i_d.di_size > 0);
			nvecs++;
		} else {
			iip->ili_format.ilf_fields &= ~XFS_ILOG_DDATA;
		}
		xfs_dir_shortform_validate(ip->i_mount, ip);
		break;

	case XFS_DINODE_FMT_DEV:
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
			  XFS_ILOG_DEXT | XFS_ILOG_UUID);
		break;

	case XFS_DINODE_FMT_UUID:
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
			  XFS_ILOG_DEXT | XFS_ILOG_DEV);
		break;

	default:
		ASSERT(0);
		break;
	}

	/*
	 * If there are no attributes associated with this file,
	 * then there cannot be anything more to log.
	 * Clear all attribute-related log flags.
	 */
	if (!XFS_IFORK_Q(ip)) {
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT | XFS_ILOG_AEXT);
		return nvecs;
	}

	/*
	 * Log any necessary attribute data.
	 */
	switch (ip->i_d.di_aformat) {
	case XFS_DINODE_FMT_EXTENTS:
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT);
		if ((iip->ili_format.ilf_fields & XFS_ILOG_AEXT) &&
		    (ip->i_d.di_anextents > 0) &&
		    (ip->i_afp->if_bytes > 0)) {
			ASSERT(ip->i_afp->if_u1.if_extents != NULL);
			nvecs++;
		} else {
			iip->ili_format.ilf_fields &= ~XFS_ILOG_AEXT;
		}
		break;

	case XFS_DINODE_FMT_BTREE:
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_ADATA | XFS_ILOG_AEXT);
		if ((iip->ili_format.ilf_fields & XFS_ILOG_ABROOT) &&
		    (ip->i_afp->if_broot_bytes > 0)) {
			ASSERT(ip->i_afp->if_broot != NULL);
			nvecs++;
		} else {
			iip->ili_format.ilf_fields &= ~XFS_ILOG_ABROOT;
		}
		break;

	case XFS_DINODE_FMT_LOCAL:
		iip->ili_format.ilf_fields &=
			~(XFS_ILOG_AEXT | XFS_ILOG_ABROOT);
		if ((iip->ili_format.ilf_fields & XFS_ILOG_ADATA) &&
		    (ip->i_afp->if_bytes > 0)) {
			ASSERT(ip->i_afp->if_u1.if_data != NULL);
			nvecs++;
		} else {
			iip->ili_format.ilf_fields &= ~XFS_ILOG_ADATA;
		}
		break;

	default:
		ASSERT(0);
		break;
	}

	return nvecs; 
}

/*
 * 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(
	xfs_inode_log_item_t	*iip,
	xfs_log_iovec_t		*log_vector)
{
	uint			nvecs;
	xfs_log_iovec_t		*vecp;
	xfs_inode_t		*ip;
	size_t			data_bytes;
	xfs_bmbt_rec_32_t	*ext_buffer;
	int			nrecs;
	xfs_mount_t		*mp;

	ip = iip->ili_inode;
	vecp = log_vector;

	vecp->i_addr = (caddr_t)&iip->ili_format;
	vecp->i_len  = sizeof(xfs_inode_log_format_t);
	vecp++;
	nvecs	     = 1;

	vecp->i_addr = (caddr_t)&ip->i_d;
	vecp->i_len  = sizeof(xfs_dinode_core_t);
	vecp++;
	nvecs++;
	iip->ili_format.ilf_fields |= XFS_ILOG_CORE;

	/*
	 * If this is really an old format inode, then we need to
	 * log it as such.  This means that we have to copy the link
	 * count from the new field to the old.  We don't have to worry
	 * about the new fields, because nothing trusts them as long as
	 * the old inode version number is there.  If the superblock already
	 * has a new version number, then we don't bother converting back.
	 */
	mp = ip->i_mount;
	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);
			ip->i_d.di_onlink = 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;
			ip->i_d.di_onlink = 0;
			bzero(&(ip->i_d.di_pad[0]), sizeof(ip->i_d.di_pad));
		}
	}

	switch (ip->i_d.di_format) {
	case XFS_DINODE_FMT_EXTENTS:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
			  XFS_ILOG_DEV | XFS_ILOG_UUID)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_DEXT) {
			ASSERT(ip->i_df.if_bytes > 0);
			ASSERT(ip->i_df.if_u1.if_extents != NULL);
			ASSERT(ip->i_d.di_nextents > 0);
			ASSERT(iip->ili_extents_buf == NULL);
			nrecs = ip->i_df.if_bytes / sizeof(xfs_bmbt_rec_t);
			ASSERT(nrecs > 0);
			if (nrecs == ip->i_d.di_nextents) {
				/*
				 * There are no delayed allocation
				 * extents, so just point to the
				 * real extents array.
				 */
				vecp->i_addr =
					(char *)(ip->i_df.if_u1.if_extents);
				vecp->i_len = ip->i_df.if_bytes;
			} else {
				/*
				 * There are delayed allocation extents
				 * in the inode.  Use xfs_iextents_copy()
				 * to copy only the real extents into
				 * a separate buffer.  We'll free the
				 * buffer in the unlock routine.
				 */
				ext_buffer = kmem_alloc(ip->i_df.if_bytes,
					KM_SLEEP);
				iip->ili_extents_buf = ext_buffer;
				vecp->i_addr = (caddr_t)ext_buffer;
				vecp->i_len = xfs_iextents_copy(ip, ext_buffer,
					XFS_DATA_FORK);
			}
			ASSERT(vecp->i_len <= ip->i_df.if_bytes);
			iip->ili_format.ilf_dsize = vecp->i_len;
			vecp++;
			nvecs++;
		}
		break;

	case XFS_DINODE_FMT_BTREE:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_DDATA | XFS_ILOG_DEXT |
			  XFS_ILOG_DEV | XFS_ILOG_UUID)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_DBROOT) {
			ASSERT(ip->i_df.if_broot_bytes > 0);
			ASSERT(ip->i_df.if_broot != NULL);
			vecp->i_addr = (caddr_t)ip->i_df.if_broot;
			vecp->i_len = ip->i_df.if_broot_bytes;
			vecp++;
			nvecs++;
			iip->ili_format.ilf_dsize = ip->i_df.if_broot_bytes;
		}
		break;

	case XFS_DINODE_FMT_LOCAL:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
			  XFS_ILOG_DEV | XFS_ILOG_UUID)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_DDATA) {
			ASSERT(ip->i_df.if_bytes > 0);
			ASSERT(ip->i_df.if_u1.if_data != NULL);
			ASSERT(ip->i_d.di_size > 0);

			vecp->i_addr = (caddr_t)ip->i_df.if_u1.if_data;
			/*
			 * 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));
			vecp->i_len = data_bytes;
			vecp++;
			nvecs++;
			iip->ili_format.ilf_dsize = data_bytes;
		}
		xfs_dir_shortform_validate(ip->i_mount, ip);
		break;

	case XFS_DINODE_FMT_DEV:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
			  XFS_ILOG_DDATA | XFS_ILOG_UUID)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_DEV) {
			iip->ili_format.ilf_u.ilfu_rdev =
				ip->i_df.if_u2.if_rdev;
		}
		break;

	case XFS_DINODE_FMT_UUID:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
			  XFS_ILOG_DDATA | XFS_ILOG_DEV)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_UUID) {
			iip->ili_format.ilf_u.ilfu_uuid =
				ip->i_df.if_u2.if_uuid;
		}
		break;

	default:
		ASSERT(0);
		break;
	}

	/*
	 * If there are no attributes associated with the file,
	 * then we're done.
	 * Assert that no attribute-related log flags are set.
	 */
	if (!XFS_IFORK_Q(ip)) {
		ASSERT(nvecs == iip->ili_item.li_desc->lid_size);
		iip->ili_format.ilf_size = nvecs;
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_ADATA | XFS_ILOG_ABROOT | XFS_ILOG_AEXT)));
		return;
	}

	switch (ip->i_d.di_aformat) {
	case XFS_DINODE_FMT_EXTENTS:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_ADATA | XFS_ILOG_ABROOT)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_AEXT) {
			ASSERT(ip->i_afp->if_bytes > 0);
			ASSERT(ip->i_afp->if_u1.if_extents != NULL);
			ASSERT(ip->i_d.di_anextents > 0);
#ifdef DEBUG
			nrecs = ip->i_afp->if_bytes / sizeof(xfs_bmbt_rec_t);
#endif
			ASSERT(nrecs > 0);
			ASSERT(nrecs == ip->i_d.di_anextents);
			/*
			 * There are not delayed allocation extents
			 * for attributes, so just point at the array.
			 */
			vecp->i_addr = (char *)(ip->i_afp->if_u1.if_extents);
			vecp->i_len = ip->i_afp->if_bytes;
			iip->ili_format.ilf_asize = vecp->i_len;
			vecp++;
			nvecs++;
		}
		break;

	case XFS_DINODE_FMT_BTREE:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_ADATA | XFS_ILOG_AEXT)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_ABROOT) {
			ASSERT(ip->i_afp->if_broot_bytes > 0);
			ASSERT(ip->i_afp->if_broot != NULL);
			vecp->i_addr = (caddr_t)ip->i_afp->if_broot;
			vecp->i_len = ip->i_afp->if_broot_bytes;
			vecp++;
			nvecs++;
			iip->ili_format.ilf_asize = ip->i_afp->if_broot_bytes;
		}
		break;

	case XFS_DINODE_FMT_LOCAL:
		ASSERT(!(iip->ili_format.ilf_fields &
			 (XFS_ILOG_ABROOT | XFS_ILOG_AEXT)));
		if (iip->ili_format.ilf_fields & XFS_ILOG_ADATA) {
			ASSERT(ip->i_afp->if_bytes > 0);
			ASSERT(ip->i_afp->if_u1.if_data != NULL);

			vecp->i_addr = (caddr_t)ip->i_afp->if_u1.if_data;
			/*
			 * 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));
			vecp->i_len = data_bytes;
			vecp++;
			nvecs++;
			iip->ili_format.ilf_asize = data_bytes;
		}
		break;

	default:
		ASSERT(0);
		break;
	}

	ASSERT(nvecs == iip->ili_item.li_desc->lid_size);
	iip->ili_format.ilf_size = nvecs;
}
	

/*
 * This is called to pin the inode associated with the inode log
 * item in memory so it cannot be written out.  Do this by calling
 * xfs_ipin() to bump the pin count in the inode while holding the
 * inode pin lock.
 */
STATIC void
xfs_inode_item_pin(
	xfs_inode_log_item_t	*iip)
{
	ASSERT(ismrlocked(&(iip->ili_inode->i_lock), MR_UPDATE));
	xfs_ipin(iip->ili_inode);
}


/*
 * 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().
 * Just call xfs_iunpin() on the inode to do this.
 */
STATIC void
xfs_inode_item_unpin(
	xfs_inode_log_item_t	*iip)
{
	xfs_iunpin(iip->ili_inode);
}

/*
 * This is called to attempt to lock the inode associated with this
 * inode log item, in preparation for the push routine which does the actual
 * iflush.  Don't sleep on the inode lock or the flush lock.
 *
 * If the flush lock is already held, indicating that the inode has
 * been or is in the process of being flushed, then (ideally) we'd like to
 * see if the inode's buffer is still incore, and if so give it a nudge.
 * We delay doing so until the pushbuf routine, though, to avoid holding
 * the AIL lock across a call to the blackhole which is the buffercache. 
 * Also we don't want to sleep in any device strategy routines, which can happen
 * if we do the subsequent bawrite in here.
 */
STATIC uint
xfs_inode_item_trylock(
	xfs_inode_log_item_t	*iip)
{
	register xfs_inode_t	*ip;

	ip = iip->ili_inode;

	if (ip->i_pincount > 0) {
		return XFS_ITEM_PINNED;
	}

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

	if (!xfs_iflock_nowait(ip)) {
		/*
		 * If someone else isn't already trying to push the inode
		 * buffer, we get to do it.
		 */
		if (iip->ili_pushbuf_flag == 0) {
			iip->ili_pushbuf_flag = 1;
#ifdef DEBUG
			iip->ili_push_owner = get_thread_id();
#endif
			/*
			 * Inode is left locked in shared mode.
			 * Pushbuf routine gets to unlock it.
			 */
			return XFS_ITEM_PUSHBUF;
		} else {
			/*
			 * We hold the AIL_LOCK, so we must specify the
			 * NONOTIFY flag so that we won't double trip.
			 */
			xfs_iunlock(ip, XFS_ILOCK_SHARED|XFS_IUNLOCK_NONOTIFY);
			return XFS_ITEM_FLUSHING;
		}
		/* NOTREACHED */
	}
	ASSERT(iip->ili_format.ilf_fields != 0);
	ASSERT(iip->ili_logged == 0);
	ASSERT(iip->ili_item.li_flags & XFS_LI_IN_AIL);
	
	return XFS_ITEM_SUCCESS;
}

/*
 * 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(
	xfs_inode_log_item_t	*iip)
{
	uint		hold;
	uint		iolocked;
	uint		lock_flags;
	xfs_inode_t	*ip;

	ASSERT(iip != NULL);
	ASSERT(iip->ili_inode->i_itemp != NULL);
	ASSERT(ismrlocked(&(iip->ili_inode->i_lock), MR_UPDATE));
	ASSERT((!(iip->ili_inode->i_itemp->ili_flags &
		  XFS_ILI_IOLOCKED_EXCL)) ||
	       ismrlocked(&(iip->ili_inode->i_iolock), MR_UPDATE));
	ASSERT((!(iip->ili_inode->i_itemp->ili_flags &
		  XFS_ILI_IOLOCKED_SHARED)) ||
	       ismrlocked(&(iip->ili_inode->i_iolock), MR_ACCESS));
	/*
	 * Clear the transaction pointer in the inode.
	 */
	ip = iip->ili_inode;
	ip->i_transp = NULL;

	/*
	 * If the inode needed a separate buffer with which to log
	 * its extents, then free it now.
	 */
	/* FIXME */
	if (iip->ili_extents_buf != NULL) {
		ASSERT(ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS);
		ASSERT(ip->i_d.di_nextents > 0);
		ASSERT(iip->ili_format.ilf_fields & XFS_ILOG_DEXT);
		ASSERT(ip->i_df.if_bytes > 0);
		kmem_free(iip->ili_extents_buf, ip->i_df.if_bytes);
		iip->ili_extents_buf = NULL;
	}

	/*
	 * Figure out if we should unlock the inode or not.
	 */
	hold = iip->ili_flags & XFS_ILI_HOLD;

	/*
	 * Before clearing out the flags, remember whether we
	 * are holding the inode's IO lock.
	 */
	iolocked = iip->ili_flags & XFS_ILI_IOLOCKED_ANY;

	/*
	 * Clear out the fields of the inode log item particular
	 * to the current transaction.
	 */
	iip->ili_ilock_recur = 0;
	iip->ili_iolock_recur = 0;
	iip->ili_flags = 0;

	/*
	 * Unlock the inode if XFS_ILI_HOLD was not set.
	 */
	if (!hold) {
		lock_flags = XFS_ILOCK_EXCL;
		if (iolocked & XFS_ILI_IOLOCKED_EXCL) {
			lock_flags |= XFS_IOLOCK_EXCL;
		} else if (iolocked & XFS_ILI_IOLOCKED_SHARED) {
			lock_flags |= XFS_IOLOCK_SHARED;
		}
		xfs_iput(iip->ili_inode, 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.
 */
/*ARGSUSED*/
STATIC xfs_lsn_t
xfs_inode_item_committed(
	xfs_inode_log_item_t	*iip,
	xfs_lsn_t		lsn)
{
	return (lsn);
}

/*
 * The transaction with the inode locked has aborted.  The inode
 * must not be dirty within the transaction.  We simply unlock just
 * as if the transaction had been cancelled.
 */
STATIC void
xfs_inode_item_abort(
	xfs_inode_log_item_t	*iip)
{
	xfs_inode_item_unlock(iip);
	return;
}


/*
 * This gets called by xfs_trans_push_ail(), when IOP_TRYLOCK
 * failed to get the inode flush lock but did get the inode locked SHARED.
 * Here we're trying to see if the inode buffer is incore, and if so whether it's
 * marked delayed write. If that's the case, we'll initiate a bawrite on that
 * buffer to expedite the process.
 *
 * We aren't holding the AIL_LOCK (or the flush lock) when this gets called,
 * so it is inherently race-y.
 */
STATIC void
xfs_inode_item_pushbuf(
	xfs_inode_log_item_t	*iip)
{
	xfs_inode_t	*ip;
	xfs_mount_t 	*mp;
	buf_t		*bp;
	uint		dopush;

	ip = iip->ili_inode;
	
	ASSERT(ismrlocked(&(ip->i_lock), MR_ACCESS));

	/*
	 * The ili_pushbuf_flag keeps others from
	 * trying to duplicate our effort.
	 */
	ASSERT(iip->ili_pushbuf_flag != 0);
	ASSERT(iip->ili_push_owner == get_thread_id());

	/*
	 * If flushlock isn't locked anymore, chances are that the
	 * inode flush completed and the inode was taken off the AIL.
	 * So, just get out.
	 */
	if ((valusema(&(ip->i_flock)) > 0)  ||
	    ((iip->ili_item.li_flags & XFS_LI_IN_AIL) == 0)) {
		iip->ili_pushbuf_flag = 0;
		xfs_iunlock(ip, XFS_ILOCK_SHARED);
	    	return;
	}
	
	mp = ip->i_mount;
	bp = incore(mp->m_dev, iip->ili_format.ilf_blkno,
		    iip->ili_format.ilf_len, INCORE_TRYLOCK);

	if (bp != NULL) {
		if (bp->b_flags & B_DELWRI) {
			/*
			 * We were racing with iflush because we don't hold
			 * the AIL_LOCK or the flush lock. However, at this point,
			 * we have the buffer, and we know that it's dirty.
			 * So, it's possible that iflush raced with us, and
			 * this item is already taken off the AIL.
			 * If not, we can flush it async.
			 */
			dopush = ((iip->ili_item.li_flags & XFS_LI_IN_AIL) && 
				  (valusema(&(ip->i_flock)) <= 0));
			iip->ili_pushbuf_flag = 0;
			xfs_iunlock(ip, XFS_ILOCK_SHARED);
#ifndef SIM
			buftrace("INODE ITEM PUSH", bp);
#endif
			if (bp->b_pincount > 0) {
				xfs_log_force(mp, (xfs_lsn_t)0,
					      XFS_LOG_FORCE);
			}
			if (dopush) {
#ifdef XFSRACEDEBUG
				delay_for_intr();
				delay(300);
#endif						
				bawrite(bp);
			} else {
				brelse(bp);
			}
		} else {
			iip->ili_pushbuf_flag = 0;
			xfs_iunlock(ip, XFS_ILOCK_SHARED); 
			brelse(bp);
		}
		return;
	}
	/*
	 * We have to be careful about resetting pushbuf flag too early (above).
	 * Eventhough in theory we can do it as soon as we have the buflock,
	 * we don't want others to be doing work needlessly. They'll come to
	 * this function thinking that pushing the buffer is there responsibility
	 * only to find that the buffer is still locked by another doing the
	 * same thing.XXX
	 */
	iip->ili_pushbuf_flag = 0;
	xfs_iunlock(ip, XFS_ILOCK_SHARED); 
	return;
}


/*
 * This is called to asynchronously write the inode associated with this
 * inode log item out to disk. The inode will already have been locked by
 * a successful call to xfs_inode_item_trylock().
 */
STATIC void
xfs_inode_item_push(
	xfs_inode_log_item_t	*iip)
{
	xfs_inode_t	*ip;

	ip = iip->ili_inode;

	ASSERT(ismrlocked(&(ip->i_lock), MR_ACCESS));
	ASSERT(valusema(&(ip->i_flock)) <= 0);
	/*
	 * Since we were able to lock the inode's flush lock and
	 * we found it on the AIL, the inode must be dirty.  This
	 * is because the inode is removed from the AIL while still
	 * holding the flush lock in xfs_iflush_done().  Thus, if
	 * we found it in the AIL and were able to obtain the flush
	 * lock without sleeping, then there must not have been
	 * anyone in the process of flushing the inode.
	 */
	ASSERT(iip->ili_format.ilf_fields != 0);

	/*
	 * Write out the inode.  The completion routine ('iflush_done') will
	 * pull it from the AIL, mark it clean, unlock the flush lock.
	 */
	xfs_iflush(ip, XFS_IFLUSH_DELWRI);
	xfs_iunlock(ip, XFS_ILOCK_SHARED);
}

/*
 * This is the ops vector shared by all buf log items.
 */
struct xfs_item_ops xfs_inode_item_ops = {
	(uint(*)(xfs_log_item_t*))xfs_inode_item_size,
	(void(*)(xfs_log_item_t*, xfs_log_iovec_t*))xfs_inode_item_format,
	(void(*)(xfs_log_item_t*))xfs_inode_item_pin,
	(void(*)(xfs_log_item_t*))xfs_inode_item_unpin,
	(uint(*)(xfs_log_item_t*))xfs_inode_item_trylock,
	(void(*)(xfs_log_item_t*))xfs_inode_item_unlock,
	(xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))xfs_inode_item_committed,
	(void(*)(xfs_log_item_t*))xfs_inode_item_push,
	(void(*)(xfs_log_item_t*))xfs_inode_item_abort,
	(void(*)(xfs_log_item_t*))xfs_inode_item_pushbuf
};


/*
 * Initialize the inode log item for a newly allocated (in-core) inode.
 */
void
xfs_inode_item_init(
	xfs_inode_t	*ip,
	xfs_mount_t	*mp)
{
	xfs_inode_log_item_t	*iip;

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

	iip->ili_item.li_type = XFS_LI_INODE;
	iip->ili_item.li_ops = &xfs_inode_item_ops;
	iip->ili_item.li_mountp = mp;
	iip->ili_inode = ip;

	/*
	   We have bzeroed memory. No need ...
	   iip->ili_extents_buf = NULL;
	   iip->ili_pushbuf_flag = 0;
	 */

	iip->ili_format.ilf_type = XFS_LI_INODE;
	iip->ili_format.ilf_ino = ip->i_ino;
	iip->ili_format.ilf_blkno = ip->i_blkno;
	iip->ili_format.ilf_len = ip->i_len;
	iip->ili_format.ilf_boffset = ip->i_boffset;
}

/*
 * Free the inode log item and any memory hanging off of it.
 */
void
xfs_inode_item_destroy(
	xfs_inode_t	*ip)
{
#ifdef XFS_TRANS_DEBUG
	if (ip->i_itemp->ili_root_size != 0) {
		kmem_free(ip->i_itemp->ili_orig_root,
			  ip->i_itemp->ili_root_size);
	}
#endif
	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.
 */
/*ARGSUSED*/
void
xfs_iflush_done(
	buf_t			*bp,
	xfs_inode_log_item_t	*iip)
{
	xfs_inode_t	*ip;
	SPLDECL(s);

	ip = iip->ili_inode;

	/*
	 * 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 (iip->ili_logged &&
	    (iip->ili_item.li_lsn == iip->ili_flush_lsn)) {
		AIL_LOCK(ip->i_mount, s);
		if (iip->ili_item.li_lsn == iip->ili_flush_lsn) {
			/*
			 * xfs_trans_delete_ail() drops the AIL lock.
			 */
			xfs_trans_delete_ail(ip->i_mount,
					     (xfs_log_item_t*)iip, s);
		} else {
			AIL_UNLOCK(ip->i_mount, s);
		}
	}
	
	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;

	/*
	 * Release the inode's flush lock since we're done with it.
	 */
	xfs_ifunlock(ip);

	return;
}