xfs_sync.c 18.7 KB
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/*
 * Copyright (c) 2000-2005 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_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_inode.h"
#include "xfs_dinode.h"
#include "xfs_error.h"
#include "xfs_mru_cache.h"
#include "xfs_filestream.h"
#include "xfs_vnodeops.h"
#include "xfs_utils.h"
#include "xfs_buf_item.h"
#include "xfs_inode_item.h"
#include "xfs_rw.h"
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#include "xfs_quota.h"
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#include "xfs_trace.h"
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#include <linux/kthread.h>
#include <linux/freezer.h>

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STATIC xfs_inode_t *
xfs_inode_ag_lookup(
	struct xfs_mount	*mp,
	struct xfs_perag	*pag,
	uint32_t		*first_index,
	int			tag)
{
	int			nr_found;
	struct xfs_inode	*ip;

	/*
	 * use a gang lookup to find the next inode in the tree
	 * as the tree is sparse and a gang lookup walks to find
	 * the number of objects requested.
	 */
	if (tag == XFS_ICI_NO_TAG) {
		nr_found = radix_tree_gang_lookup(&pag->pag_ici_root,
				(void **)&ip, *first_index, 1);
	} else {
		nr_found = radix_tree_gang_lookup_tag(&pag->pag_ici_root,
				(void **)&ip, *first_index, 1, tag);
	}
	if (!nr_found)
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		return NULL;
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	/*
	 * Update the index for the next lookup. Catch overflows
	 * into the next AG range which can occur if we have inodes
	 * in the last block of the AG and we are currently
	 * pointing to the last inode.
	 */
	*first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1);
	if (*first_index < XFS_INO_TO_AGINO(mp, ip->i_ino))
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		return NULL;
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	return ip;
}

STATIC int
xfs_inode_ag_walk(
	struct xfs_mount	*mp,
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	struct xfs_perag	*pag,
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	int			(*execute)(struct xfs_inode *ip,
					   struct xfs_perag *pag, int flags),
	int			flags,
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	int			tag,
	int			exclusive)
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{
	uint32_t		first_index;
	int			last_error = 0;
	int			skipped;

restart:
	skipped = 0;
	first_index = 0;
	do {
		int		error = 0;
		xfs_inode_t	*ip;

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		if (exclusive)
			write_lock(&pag->pag_ici_lock);
		else
			read_lock(&pag->pag_ici_lock);
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		ip = xfs_inode_ag_lookup(mp, pag, &first_index, tag);
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		if (!ip) {
			if (exclusive)
				write_unlock(&pag->pag_ici_lock);
			else
				read_unlock(&pag->pag_ici_lock);
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			break;
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		}
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		/* execute releases pag->pag_ici_lock */
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		error = execute(ip, pag, flags);
		if (error == EAGAIN) {
			skipped++;
			continue;
		}
		if (error)
			last_error = error;
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		/* bail out if the filesystem is corrupted.  */
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		if (error == EFSCORRUPTED)
			break;

	} while (1);

	if (skipped) {
		delay(1);
		goto restart;
	}
	return last_error;
}

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int
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xfs_inode_ag_iterator(
	struct xfs_mount	*mp,
	int			(*execute)(struct xfs_inode *ip,
					   struct xfs_perag *pag, int flags),
	int			flags,
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	int			tag,
	int			exclusive)
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{
	int			error = 0;
	int			last_error = 0;
	xfs_agnumber_t		ag;

	for (ag = 0; ag < mp->m_sb.sb_agcount; ag++) {
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		struct xfs_perag	*pag;

		pag = xfs_perag_get(mp, ag);
		if (!pag->pag_ici_init) {
			xfs_perag_put(pag);
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			continue;
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		}
		error = xfs_inode_ag_walk(mp, pag, execute, flags, tag,
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						exclusive);
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		xfs_perag_put(pag);
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		if (error) {
			last_error = error;
			if (error == EFSCORRUPTED)
				break;
		}
	}
	return XFS_ERROR(last_error);
}

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/* must be called with pag_ici_lock held and releases it */
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int
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xfs_sync_inode_valid(
	struct xfs_inode	*ip,
	struct xfs_perag	*pag)
{
	struct inode		*inode = VFS_I(ip);
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	int			error = EFSCORRUPTED;
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	/* nothing to sync during shutdown */
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	if (XFS_FORCED_SHUTDOWN(ip->i_mount))
		goto out_unlock;
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	/* avoid new or reclaimable inodes. Leave for reclaim code to flush */
	error = ENOENT;
	if (xfs_iflags_test(ip, XFS_INEW | XFS_IRECLAIMABLE | XFS_IRECLAIM))
		goto out_unlock;
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	/* If we can't grab the inode, it must on it's way to reclaim. */
	if (!igrab(inode))
		goto out_unlock;

	if (is_bad_inode(inode)) {
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		IRELE(ip);
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		goto out_unlock;
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	}

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	/* inode is valid */
	error = 0;
out_unlock:
	read_unlock(&pag->pag_ici_lock);
	return error;
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}

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STATIC int
xfs_sync_inode_data(
	struct xfs_inode	*ip,
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	struct xfs_perag	*pag,
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	int			flags)
{
	struct inode		*inode = VFS_I(ip);
	struct address_space *mapping = inode->i_mapping;
	int			error = 0;

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	error = xfs_sync_inode_valid(ip, pag);
	if (error)
		return error;

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	if (!mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
		goto out_wait;

	if (!xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED)) {
		if (flags & SYNC_TRYLOCK)
			goto out_wait;
		xfs_ilock(ip, XFS_IOLOCK_SHARED);
	}

	error = xfs_flush_pages(ip, 0, -1, (flags & SYNC_WAIT) ?
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				0 : XBF_ASYNC, FI_NONE);
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	xfs_iunlock(ip, XFS_IOLOCK_SHARED);

 out_wait:
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	if (flags & SYNC_WAIT)
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		xfs_ioend_wait(ip);
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	IRELE(ip);
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	return error;
}

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STATIC int
xfs_sync_inode_attr(
	struct xfs_inode	*ip,
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	struct xfs_perag	*pag,
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	int			flags)
{
	int			error = 0;

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	error = xfs_sync_inode_valid(ip, pag);
	if (error)
		return error;

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	xfs_ilock(ip, XFS_ILOCK_SHARED);
	if (xfs_inode_clean(ip))
		goto out_unlock;
	if (!xfs_iflock_nowait(ip)) {
		if (!(flags & SYNC_WAIT))
			goto out_unlock;
		xfs_iflock(ip);
	}

	if (xfs_inode_clean(ip)) {
		xfs_ifunlock(ip);
		goto out_unlock;
	}

	error = xfs_iflush(ip, (flags & SYNC_WAIT) ?
			   XFS_IFLUSH_SYNC : XFS_IFLUSH_DELWRI);

 out_unlock:
	xfs_iunlock(ip, XFS_ILOCK_SHARED);
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	IRELE(ip);
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	return error;
}

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/*
 * Write out pagecache data for the whole filesystem.
 */
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int
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xfs_sync_data(
	struct xfs_mount	*mp,
	int			flags)
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{
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	int			error;
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	ASSERT((flags & ~(SYNC_TRYLOCK|SYNC_WAIT)) == 0);
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	error = xfs_inode_ag_iterator(mp, xfs_sync_inode_data, flags,
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				      XFS_ICI_NO_TAG, 0);
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	if (error)
		return XFS_ERROR(error);
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	xfs_log_force(mp, (flags & SYNC_WAIT) ? XFS_LOG_SYNC : 0);
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	return 0;
}
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/*
 * Write out inode metadata (attributes) for the whole filesystem.
 */
int
xfs_sync_attr(
	struct xfs_mount	*mp,
	int			flags)
{
	ASSERT((flags & ~SYNC_WAIT) == 0);
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	return xfs_inode_ag_iterator(mp, xfs_sync_inode_attr, flags,
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				     XFS_ICI_NO_TAG, 0);
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}

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STATIC int
xfs_commit_dummy_trans(
	struct xfs_mount	*mp,
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	uint			flags)
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{
	struct xfs_inode	*ip = mp->m_rootip;
	struct xfs_trans	*tp;
	int			error;

	/*
	 * Put a dummy transaction in the log to tell recovery
	 * that all others are OK.
	 */
	tp = xfs_trans_alloc(mp, XFS_TRANS_DUMMY1);
	error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0);
	if (error) {
		xfs_trans_cancel(tp, 0);
		return error;
	}

	xfs_ilock(ip, XFS_ILOCK_EXCL);

	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
	xfs_trans_ihold(tp, ip);
	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
	error = xfs_trans_commit(tp, 0);
	xfs_iunlock(ip, XFS_ILOCK_EXCL);

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	/* the log force ensures this transaction is pushed to disk */
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	xfs_log_force(mp, (flags & SYNC_WAIT) ? XFS_LOG_SYNC : 0);
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	return error;
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}

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STATIC int
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xfs_sync_fsdata(
	struct xfs_mount	*mp,
	int			flags)
{
	struct xfs_buf		*bp;
	struct xfs_buf_log_item	*bip;
	int			error = 0;

	/*
	 * If this is xfssyncd() then only sync the superblock if we can
	 * lock it without sleeping and it is not pinned.
	 */
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	if (flags & SYNC_TRYLOCK) {
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		ASSERT(!(flags & SYNC_WAIT));

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		bp = xfs_getsb(mp, XBF_TRYLOCK);
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		if (!bp)
			goto out;

		bip = XFS_BUF_FSPRIVATE(bp, struct xfs_buf_log_item *);
		if (!bip || !xfs_buf_item_dirty(bip) || XFS_BUF_ISPINNED(bp))
			goto out_brelse;
	} else {
		bp = xfs_getsb(mp, 0);

		/*
		 * If the buffer is pinned then push on the log so we won't
		 * get stuck waiting in the write for someone, maybe
		 * ourselves, to flush the log.
		 *
		 * Even though we just pushed the log above, we did not have
		 * the superblock buffer locked at that point so it can
		 * become pinned in between there and here.
		 */
		if (XFS_BUF_ISPINNED(bp))
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			xfs_log_force(mp, 0);
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	}


	if (flags & SYNC_WAIT)
		XFS_BUF_UNASYNC(bp);
	else
		XFS_BUF_ASYNC(bp);

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	error = xfs_bwrite(mp, bp);
	if (error)
		return error;

	/*
	 * If this is a data integrity sync make sure all pending buffers
	 * are flushed out for the log coverage check below.
	 */
	if (flags & SYNC_WAIT)
		xfs_flush_buftarg(mp->m_ddev_targp, 1);

	if (xfs_log_need_covered(mp))
		error = xfs_commit_dummy_trans(mp, flags);
	return error;
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 out_brelse:
	xfs_buf_relse(bp);
 out:
	return error;
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}

/*
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 * When remounting a filesystem read-only or freezing the filesystem, we have
 * two phases to execute. This first phase is syncing the data before we
 * quiesce the filesystem, and the second is flushing all the inodes out after
 * we've waited for all the transactions created by the first phase to
 * complete. The second phase ensures that the inodes are written to their
 * location on disk rather than just existing in transactions in the log. This
 * means after a quiesce there is no log replay required to write the inodes to
 * disk (this is the main difference between a sync and a quiesce).
 */
/*
 * First stage of freeze - no writers will make progress now we are here,
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 * so we flush delwri and delalloc buffers here, then wait for all I/O to
 * complete.  Data is frozen at that point. Metadata is not frozen,
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 * transactions can still occur here so don't bother flushing the buftarg
 * because it'll just get dirty again.
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 */
int
xfs_quiesce_data(
	struct xfs_mount	*mp)
{
	int error;

	/* push non-blocking */
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	xfs_sync_data(mp, 0);
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	xfs_qm_sync(mp, SYNC_TRYLOCK);
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	/* push and block till complete */
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	xfs_sync_data(mp, SYNC_WAIT);
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	xfs_qm_sync(mp, SYNC_WAIT);
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	/* write superblock and hoover up shutdown errors */
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	error = xfs_sync_fsdata(mp, SYNC_WAIT);
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	/* flush data-only devices */
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	if (mp->m_rtdev_targp)
		XFS_bflush(mp->m_rtdev_targp);

	return error;
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}

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STATIC void
xfs_quiesce_fs(
	struct xfs_mount	*mp)
{
	int	count = 0, pincount;

	xfs_flush_buftarg(mp->m_ddev_targp, 0);
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	xfs_reclaim_inodes(mp, XFS_IFLUSH_DELWRI_ELSE_ASYNC);
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	/*
	 * This loop must run at least twice.  The first instance of the loop
	 * will flush most meta data but that will generate more meta data
	 * (typically directory updates).  Which then must be flushed and
	 * logged before we can write the unmount record.
	 */
	do {
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		xfs_sync_attr(mp, SYNC_WAIT);
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		pincount = xfs_flush_buftarg(mp->m_ddev_targp, 1);
		if (!pincount) {
			delay(50);
			count++;
		}
	} while (count < 2);
}

/*
 * Second stage of a quiesce. The data is already synced, now we have to take
 * care of the metadata. New transactions are already blocked, so we need to
 * wait for any remaining transactions to drain out before proceding.
 */
void
xfs_quiesce_attr(
	struct xfs_mount	*mp)
{
	int	error = 0;

	/* wait for all modifications to complete */
	while (atomic_read(&mp->m_active_trans) > 0)
		delay(100);

	/* flush inodes and push all remaining buffers out to disk */
	xfs_quiesce_fs(mp);

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	/*
	 * Just warn here till VFS can correctly support
	 * read-only remount without racing.
	 */
	WARN_ON(atomic_read(&mp->m_active_trans) != 0);
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	/* Push the superblock and write an unmount record */
	error = xfs_log_sbcount(mp, 1);
	if (error)
		xfs_fs_cmn_err(CE_WARN, mp,
				"xfs_attr_quiesce: failed to log sb changes. "
				"Frozen image may not be consistent.");
	xfs_log_unmount_write(mp);
	xfs_unmountfs_writesb(mp);
}

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/*
 * Enqueue a work item to be picked up by the vfs xfssyncd thread.
 * Doing this has two advantages:
 * - It saves on stack space, which is tight in certain situations
 * - It can be used (with care) as a mechanism to avoid deadlocks.
 * Flushing while allocating in a full filesystem requires both.
 */
STATIC void
xfs_syncd_queue_work(
	struct xfs_mount *mp,
	void		*data,
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	void		(*syncer)(struct xfs_mount *, void *),
	struct completion *completion)
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{
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	struct xfs_sync_work *work;
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	work = kmem_alloc(sizeof(struct xfs_sync_work), KM_SLEEP);
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	INIT_LIST_HEAD(&work->w_list);
	work->w_syncer = syncer;
	work->w_data = data;
	work->w_mount = mp;
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	work->w_completion = completion;
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	spin_lock(&mp->m_sync_lock);
	list_add_tail(&work->w_list, &mp->m_sync_list);
	spin_unlock(&mp->m_sync_lock);
	wake_up_process(mp->m_sync_task);
}

/*
 * Flush delayed allocate data, attempting to free up reserved space
 * from existing allocations.  At this point a new allocation attempt
 * has failed with ENOSPC and we are in the process of scratching our
 * heads, looking about for more room...
 */
STATIC void
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xfs_flush_inodes_work(
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	struct xfs_mount *mp,
	void		*arg)
{
	struct inode	*inode = arg;
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	xfs_sync_data(mp, SYNC_TRYLOCK);
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	xfs_sync_data(mp, SYNC_TRYLOCK | SYNC_WAIT);
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	iput(inode);
}

void
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xfs_flush_inodes(
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	xfs_inode_t	*ip)
{
	struct inode	*inode = VFS_I(ip);
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	DECLARE_COMPLETION_ONSTACK(completion);
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	igrab(inode);
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	xfs_syncd_queue_work(ip->i_mount, inode, xfs_flush_inodes_work, &completion);
	wait_for_completion(&completion);
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	xfs_log_force(ip->i_mount, XFS_LOG_SYNC);
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}

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/*
 * Every sync period we need to unpin all items, reclaim inodes, sync
 * quota and write out the superblock. We might need to cover the log
 * to indicate it is idle.
 */
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STATIC void
xfs_sync_worker(
	struct xfs_mount *mp,
	void		*unused)
{
	int		error;

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	if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
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		xfs_log_force(mp, 0);
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		xfs_reclaim_inodes(mp, XFS_IFLUSH_DELWRI_ELSE_ASYNC);
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		/* dgc: errors ignored here */
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		error = xfs_qm_sync(mp, SYNC_TRYLOCK);
		error = xfs_sync_fsdata(mp, SYNC_TRYLOCK);
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	}
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	mp->m_sync_seq++;
	wake_up(&mp->m_wait_single_sync_task);
}

STATIC int
xfssyncd(
	void			*arg)
{
	struct xfs_mount	*mp = arg;
	long			timeleft;
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	xfs_sync_work_t		*work, *n;
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	LIST_HEAD		(tmp);

	set_freezable();
	timeleft = xfs_syncd_centisecs * msecs_to_jiffies(10);
	for (;;) {
		timeleft = schedule_timeout_interruptible(timeleft);
		/* swsusp */
		try_to_freeze();
		if (kthread_should_stop() && list_empty(&mp->m_sync_list))
			break;

		spin_lock(&mp->m_sync_lock);
		/*
		 * We can get woken by laptop mode, to do a sync -
		 * that's the (only!) case where the list would be
		 * empty with time remaining.
		 */
		if (!timeleft || list_empty(&mp->m_sync_list)) {
			if (!timeleft)
				timeleft = xfs_syncd_centisecs *
							msecs_to_jiffies(10);
			INIT_LIST_HEAD(&mp->m_sync_work.w_list);
			list_add_tail(&mp->m_sync_work.w_list,
					&mp->m_sync_list);
		}
		list_for_each_entry_safe(work, n, &mp->m_sync_list, w_list)
			list_move(&work->w_list, &tmp);
		spin_unlock(&mp->m_sync_lock);

		list_for_each_entry_safe(work, n, &tmp, w_list) {
			(*work->w_syncer)(mp, work->w_data);
			list_del(&work->w_list);
			if (work == &mp->m_sync_work)
				continue;
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			if (work->w_completion)
				complete(work->w_completion);
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			kmem_free(work);
		}
	}

	return 0;
}

int
xfs_syncd_init(
	struct xfs_mount	*mp)
{
	mp->m_sync_work.w_syncer = xfs_sync_worker;
	mp->m_sync_work.w_mount = mp;
653
	mp->m_sync_work.w_completion = NULL;
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	mp->m_sync_task = kthread_run(xfssyncd, mp, "xfssyncd");
	if (IS_ERR(mp->m_sync_task))
		return -PTR_ERR(mp->m_sync_task);
	return 0;
}

void
xfs_syncd_stop(
	struct xfs_mount	*mp)
{
	kthread_stop(mp->m_sync_task);
}

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void
__xfs_inode_set_reclaim_tag(
	struct xfs_perag	*pag,
	struct xfs_inode	*ip)
{
	radix_tree_tag_set(&pag->pag_ici_root,
			   XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino),
			   XFS_ICI_RECLAIM_TAG);
}

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/*
 * We set the inode flag atomically with the radix tree tag.
 * Once we get tag lookups on the radix tree, this inode flag
 * can go away.
 */
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void
xfs_inode_set_reclaim_tag(
	xfs_inode_t	*ip)
{
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	struct xfs_mount *mp = ip->i_mount;
	struct xfs_perag *pag;
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	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
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	read_lock(&pag->pag_ici_lock);
	spin_lock(&ip->i_flags_lock);
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	__xfs_inode_set_reclaim_tag(pag, ip);
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	__xfs_iflags_set(ip, XFS_IRECLAIMABLE);
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	spin_unlock(&ip->i_flags_lock);
	read_unlock(&pag->pag_ici_lock);
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	xfs_perag_put(pag);
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}

void
__xfs_inode_clear_reclaim_tag(
	xfs_mount_t	*mp,
	xfs_perag_t	*pag,
	xfs_inode_t	*ip)
{
	radix_tree_tag_clear(&pag->pag_ici_root,
			XFS_INO_TO_AGINO(mp, ip->i_ino), XFS_ICI_RECLAIM_TAG);
}

709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737
/*
 * Inodes in different states need to be treated differently, and the return
 * value of xfs_iflush is not sufficient to get this right. The following table
 * lists the inode states and the reclaim actions necessary for non-blocking
 * reclaim:
 *
 *
 *	inode state	     iflush ret		required action
 *      ---------------      ----------         ---------------
 *	bad			-		reclaim
 *	shutdown		EIO		unpin and reclaim
 *	clean, unpinned		0		reclaim
 *	stale, unpinned		0		reclaim
 *	clean, pinned(*)	0		unpin and reclaim
 *	stale, pinned		0		unpin and reclaim
 *	dirty, async		0		block on flush lock, reclaim
 *	dirty, sync flush	0		block on flush lock, reclaim
 *
 * (*) dgc: I don't think the clean, pinned state is possible but it gets
 * handled anyway given the order of checks implemented.
 *
 * Hence the order of actions after gaining the locks should be:
 *	bad		=> reclaim
 *	shutdown	=> unpin and reclaim
 *	pinned		=> unpin
 *	stale		=> reclaim
 *	clean		=> reclaim
 *	dirty		=> flush, wait and reclaim
 */
738
STATIC int
739
xfs_reclaim_inode(
740 741
	struct xfs_inode	*ip,
	struct xfs_perag	*pag,
742
	int			sync_mode)
743
{
744 745
	int	error;

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	/*
	 * The radix tree lock here protects a thread in xfs_iget from racing
	 * with us starting reclaim on the inode.  Once we have the
	 * XFS_IRECLAIM flag set it will not touch us.
	 */
	spin_lock(&ip->i_flags_lock);
	ASSERT_ALWAYS(__xfs_iflags_test(ip, XFS_IRECLAIMABLE));
	if (__xfs_iflags_test(ip, XFS_IRECLAIM)) {
		/* ignore as it is already under reclaim */
		spin_unlock(&ip->i_flags_lock);
		write_unlock(&pag->pag_ici_lock);
757
		return 0;
758
	}
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	__xfs_iflags_set(ip, XFS_IRECLAIM);
	spin_unlock(&ip->i_flags_lock);
	write_unlock(&pag->pag_ici_lock);

	xfs_ilock(ip, XFS_ILOCK_EXCL);
	xfs_iflock(ip);
765

766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794
	if (is_bad_inode(VFS_I(ip)))
		goto reclaim;
	if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
		xfs_iunpin_wait(ip);
		goto reclaim;
	}
	if (xfs_ipincount(ip))
		xfs_iunpin_wait(ip);
	if (xfs_iflags_test(ip, XFS_ISTALE))
		goto reclaim;
	if (xfs_inode_clean(ip))
		goto reclaim;

	/* Now we have an inode that needs flushing */
	error = xfs_iflush(ip, sync_mode);
	if (!error) {
		switch(sync_mode) {
		case XFS_IFLUSH_DELWRI_ELSE_ASYNC:
		case XFS_IFLUSH_DELWRI:
		case XFS_IFLUSH_ASYNC:
		case XFS_IFLUSH_DELWRI_ELSE_SYNC:
		case XFS_IFLUSH_SYNC:
			/* IO issued, synchronise with IO completion */
			xfs_iflock(ip);
			break;
		default:
			ASSERT(0);
			break;
		}
795 796
	}

797 798
reclaim:
	xfs_ifunlock(ip);
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	xfs_iunlock(ip, XFS_ILOCK_EXCL);
	xfs_ireclaim(ip);
	return 0;
802 803 804 805 806 807 808
}

int
xfs_reclaim_inodes(
	xfs_mount_t	*mp,
	int		mode)
{
809 810
	return xfs_inode_ag_iterator(mp, xfs_reclaim_inode, mode,
					XFS_ICI_RECLAIM_TAG, 1);
811
}