Commit 4805621a authored by From: Christoph Hellwig's avatar From: Christoph Hellwig Committed by Niv Sardi
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[XFS] factor out xfs_read_agf helper 



Add a helper to read the AGF header and perform basic verification.
Based on hunks from a larger patch from Dave Chinner.

(First sent on Juli 23rd)

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDave Chinner <david@fromorbit.com>
Signed-off-by: default avatarNiv Sardi <xaiki@sgi.com>
parent 5e1be0fb

fs/xfs/xfs_ag.h

+2 −0
Original line number Diff line number Diff line
@@ -91,6 +91,8 @@ typedef struct xfs_agf { 
#define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))

#define	XFS_BUF_TO_AGF(bp)	((xfs_agf_t *)XFS_BUF_PTR(bp))



extern int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,

			xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);



/*

 * Size of the unlinked inode hash table in the agi.

fs/xfs/xfs_alloc.c

+48 −21
Original line number Diff line number Diff line
@@ -2233,44 +2233,41 @@ xfs_alloc_put_freelist( 
 * Read in the allocation group header (free/alloc section).

 */

int					/* error */

xfs_alloc_read_agf(

	xfs_mount_t	*mp,		/* mount point structure */

	xfs_trans_t	*tp,		/* transaction pointer */

xfs_read_agf(

	struct xfs_mount	*mp,	/* mount point structure */

	struct xfs_trans	*tp,	/* transaction pointer */

	xfs_agnumber_t		agno,	/* allocation group number */

	int		flags,		/* XFS_ALLOC_FLAG_... */

	xfs_buf_t	**bpp)		/* buffer for the ag freelist header */

	int			flags,	/* XFS_BUF_ */

	struct xfs_buf		**bpp)	/* buffer for the ag freelist header */

{

	xfs_agf_t	*agf;		/* ag freelist header */

	struct xfs_agf	*agf;		/* ag freelist header */

	int		agf_ok;		/* set if agf is consistent */

	xfs_buf_t	*bp;		/* return value */

	xfs_perag_t	*pag;		/* per allocation group data */

	int		error;



	ASSERT(agno != NULLAGNUMBER);

	error = xfs_trans_read_buf(

			mp, tp, mp->m_ddev_targp,

			XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),

			XFS_FSS_TO_BB(mp, 1),

			(flags & XFS_ALLOC_FLAG_TRYLOCK) ? XFS_BUF_TRYLOCK : 0U,

			&bp);

			XFS_FSS_TO_BB(mp, 1), flags, bpp);

	if (error)

		return error;

	ASSERT(!bp || !XFS_BUF_GETERROR(bp));

	if (!bp) {

		*bpp = NULL;

	if (!*bpp)

		return 0;

	}



	ASSERT(!XFS_BUF_GETERROR(*bpp));

	agf = XFS_BUF_TO_AGF(*bpp);



	/*

	 * Validate the magic number of the agf block.

	 */

	agf = XFS_BUF_TO_AGF(bp);

	agf_ok =

		be32_to_cpu(agf->agf_magicnum) == XFS_AGF_MAGIC &&

		XFS_AGF_GOOD_VERSION(be32_to_cpu(agf->agf_versionnum)) &&

		be32_to_cpu(agf->agf_freeblks) <= be32_to_cpu(agf->agf_length) &&

		be32_to_cpu(agf->agf_flfirst) < XFS_AGFL_SIZE(mp) &&

		be32_to_cpu(agf->agf_fllast) < XFS_AGFL_SIZE(mp) &&

		be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp);

		be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp) &&

		be32_to_cpu(agf->agf_seqno) == agno;

	if (xfs_sb_version_haslazysbcount(&mp->m_sb))

		agf_ok = agf_ok && be32_to_cpu(agf->agf_btreeblks) <=

						be32_to_cpu(agf->agf_length);
@@ -2278,9 +2275,41 @@ xfs_alloc_read_agf( 
			XFS_RANDOM_ALLOC_READ_AGF))) {

		XFS_CORRUPTION_ERROR("xfs_alloc_read_agf",

				     XFS_ERRLEVEL_LOW, mp, agf);

		xfs_trans_brelse(tp, bp);

		xfs_trans_brelse(tp, *bpp);

		return XFS_ERROR(EFSCORRUPTED);

	}



	XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_AGF, XFS_AGF_REF);

	return 0;

}



/*

 * Read in the allocation group header (free/alloc section).

 */

int					/* error */

xfs_alloc_read_agf(

	struct xfs_mount	*mp,	/* mount point structure */

	struct xfs_trans	*tp,	/* transaction pointer */

	xfs_agnumber_t		agno,	/* allocation group number */

	int			flags,	/* XFS_ALLOC_FLAG_... */

	struct xfs_buf		**bpp)	/* buffer for the ag freelist header */

{

	struct xfs_agf		*agf;		/* ag freelist header */

	struct xfs_perag	*pag;		/* per allocation group data */

	int			error;



	ASSERT(agno != NULLAGNUMBER);



	error = xfs_read_agf(mp, tp, agno,

			(flags & XFS_ALLOC_FLAG_TRYLOCK) ? XFS_BUF_TRYLOCK : 0,

			bpp);

	if (error)

		return error;

	if (!*bpp)

		return 0;

	ASSERT(!XFS_BUF_GETERROR(*bpp));



	agf = XFS_BUF_TO_AGF(*bpp);

	pag = &mp->m_perag[agno];

	if (!pag->pagf_init) {

		pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks);
@@ -2308,8 +2337,6 @@ xfs_alloc_read_agf( 
		       be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]));

	}

#endif

	XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGF, XFS_AGF_REF);

	*bpp = bp;

	return 0;

}

fs/xfs/xfs_log_recover.c

+11 −15
Original line number Diff line number Diff line
@@ -3970,7 +3970,6 @@ xlog_recover_check_summary( 
	xfs_agf_t	*agfp;

	xfs_buf_t	*agfbp;

	xfs_buf_t	*agibp;

	xfs_daddr_t	agfdaddr;

	xfs_buf_t	*sbbp;

#ifdef XFS_LOUD_RECOVERY

	xfs_sb_t	*sbp;
@@ -3987,21 +3986,18 @@ xlog_recover_check_summary( 
	itotal = 0LL;

	ifree = 0LL;

	for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {

		agfdaddr = XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp));

		agfbp = xfs_buf_read(mp->m_ddev_targp, agfdaddr,

				XFS_FSS_TO_BB(mp, 1), 0);

		if (XFS_BUF_ISERROR(agfbp)) {

			xfs_ioerror_alert("xlog_recover_check_summary(agf)",

						mp, agfbp, agfdaddr);

		}

		error = xfs_read_agf(mp, NULL, agno, 0, &agfbp);

		if (error) {

			xfs_fs_cmn_err(CE_ALERT, mp,

					"xlog_recover_check_summary(agf)"

					"agf read failed agno %d error %d",

							agno, error);

		} else {

			agfp = XFS_BUF_TO_AGF(agfbp);

		ASSERT(XFS_AGF_MAGIC == be32_to_cpu(agfp->agf_magicnum));

		ASSERT(XFS_AGF_GOOD_VERSION(be32_to_cpu(agfp->agf_versionnum)));

		ASSERT(be32_to_cpu(agfp->agf_seqno) == agno);



			freeblks += be32_to_cpu(agfp->agf_freeblks) +

				    be32_to_cpu(agfp->agf_flcount);

			xfs_buf_relse(agfbp);

		}



		error = xfs_read_agi(mp, NULL, agno, &agibp);

		if (!error) {

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