Commit 27b52867 authored by Brian Foster's avatar Brian Foster Committed by Ben Myers
Browse files

xfs: add EOFBLOCKS inode tagging/untagging 



Add the XFS_ICI_EOFBLOCKS_TAG inode tag to identify inodes with
speculatively preallocated blocks beyond EOF. An inode is tagged
when speculative preallocation occurs and untagged either via
truncate down or when post-EOF blocks are freed via release or
reclaim.

The tag management is intentionally not aggressive to prefer
simplicity over the complexity of handling all the corner cases
under which post-EOF blocks could be freed (i.e., forward
truncation, fallocate, write error conditions, etc.). This means
that a tagged inode may or may not have post-EOF blocks after a
period of time. The tag is eventually cleared when the inode is
released or reclaimed.

Signed-off-by: default avatarBrian Foster <bfoster@redhat.com>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarMark Tinguely <tinguely@sgi.com>
Signed-off-by: default avatarBen Myers <bpm@sgi.com>
parent 69a58a43

fs/xfs/xfs_ag.h

+1 −0
Original line number Diff line number Diff line
@@ -233,6 +233,7 @@ typedef struct xfs_perag { 
#define XFS_ICI_NO_TAG		(-1)	/* special flag for an untagged lookup

					   in xfs_inode_ag_iterator */

#define XFS_ICI_RECLAIM_TAG	0	/* inode is to be reclaimed */

#define XFS_ICI_EOFBLOCKS_TAG	1	/* inode has blocks beyond EOF */



#define	XFS_AG_MAXLEVELS(mp)		((mp)->m_ag_maxlevels)

#define	XFS_MIN_FREELIST_RAW(bl,cl,mp)	\

fs/xfs/xfs_icache.c

+62 −0
Original line number Diff line number Diff line
@@ -1128,3 +1128,65 @@ xfs_reclaim_inodes_count( 
	return reclaimable;

}



void

xfs_inode_set_eofblocks_tag(

	xfs_inode_t	*ip)

{

	struct xfs_mount *mp = ip->i_mount;

	struct xfs_perag *pag;

	int tagged;



	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));

	spin_lock(&pag->pag_ici_lock);

	trace_xfs_inode_set_eofblocks_tag(ip);



	tagged = radix_tree_tagged(&pag->pag_ici_root,

				   XFS_ICI_EOFBLOCKS_TAG);

	radix_tree_tag_set(&pag->pag_ici_root,

			   XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino),

			   XFS_ICI_EOFBLOCKS_TAG);

	if (!tagged) {

		/* propagate the eofblocks tag up into the perag radix tree */

		spin_lock(&ip->i_mount->m_perag_lock);

		radix_tree_tag_set(&ip->i_mount->m_perag_tree,

				   XFS_INO_TO_AGNO(ip->i_mount, ip->i_ino),

				   XFS_ICI_EOFBLOCKS_TAG);

		spin_unlock(&ip->i_mount->m_perag_lock);



		trace_xfs_perag_set_eofblocks(ip->i_mount, pag->pag_agno,

					      -1, _RET_IP_);

	}



	spin_unlock(&pag->pag_ici_lock);

	xfs_perag_put(pag);

}



void

xfs_inode_clear_eofblocks_tag(

	xfs_inode_t	*ip)

{

	struct xfs_mount *mp = ip->i_mount;

	struct xfs_perag *pag;



	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));

	spin_lock(&pag->pag_ici_lock);

	trace_xfs_inode_clear_eofblocks_tag(ip);



	radix_tree_tag_clear(&pag->pag_ici_root,

			     XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino),

			     XFS_ICI_EOFBLOCKS_TAG);

	if (!radix_tree_tagged(&pag->pag_ici_root, XFS_ICI_EOFBLOCKS_TAG)) {

		/* clear the eofblocks tag from the perag radix tree */

		spin_lock(&ip->i_mount->m_perag_lock);

		radix_tree_tag_clear(&ip->i_mount->m_perag_tree,

				     XFS_INO_TO_AGNO(ip->i_mount, ip->i_ino),

				     XFS_ICI_EOFBLOCKS_TAG);

		spin_unlock(&ip->i_mount->m_perag_lock);

		trace_xfs_perag_clear_eofblocks(ip->i_mount, pag->pag_agno,

					       -1, _RET_IP_);

	}



	spin_unlock(&pag->pag_ici_lock);

	xfs_perag_put(pag);

}

fs/xfs/xfs_icache.h

+3 −0
Original line number Diff line number Diff line
@@ -35,6 +35,9 @@ void xfs_reclaim_inodes_nr(struct xfs_mount *mp, int nr_to_scan); 


void xfs_inode_set_reclaim_tag(struct xfs_inode *ip);



void xfs_inode_set_eofblocks_tag(struct xfs_inode *ip);

void xfs_inode_clear_eofblocks_tag(struct xfs_inode *ip);



int xfs_sync_inode_grab(struct xfs_inode *ip);

int xfs_inode_ag_iterator(struct xfs_mount *mp,

	int (*execute)(struct xfs_inode *ip, struct xfs_perag *pag, int flags),

fs/xfs/xfs_iomap.c

+8 −0
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ 
#include "xfs_utils.h"

#include "xfs_iomap.h"

#include "xfs_trace.h"

#include "xfs_icache.h"





#define XFS_WRITEIO_ALIGN(mp,off)	(((off) >> mp->m_writeio_log) \
@@ -450,6 +451,13 @@ retry: 
	if (!(imap[0].br_startblock || XFS_IS_REALTIME_INODE(ip)))

		return xfs_alert_fsblock_zero(ip, &imap[0]);



	/*

	 * Tag the inode as speculatively preallocated so we can reclaim this

	 * space on demand, if necessary.

	 */

	if (prealloc)

		xfs_inode_set_eofblocks_tag(ip);



	*ret_imap = imap[0];

	return 0;

}

fs/xfs/xfs_iops.c

+4 −0
Original line number Diff line number Diff line
@@ -38,6 +38,7 @@ 
#include "xfs_vnodeops.h"

#include "xfs_inode_item.h"

#include "xfs_trace.h"

#include "xfs_icache.h"



#include <linux/capability.h>

#include <linux/xattr.h>
@@ -854,6 +855,9 @@ xfs_setattr_size( 
		 * and do not wait the usual (long) time for writeout.

		 */

		xfs_iflags_set(ip, XFS_ITRUNCATED);



		/* A truncate down always removes post-EOF blocks. */

		xfs_inode_clear_eofblocks_tag(ip);

	}



	if (mask & ATTR_CTIME) {

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