From 5e1be0fb1a3950597aeda448698e85b0595a2e92 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 28 Nov 2008 14:23:37 +1100 Subject: [XFS] factor out xfs_read_agi helper Add a helper to read the AGI header and perform basic verification. Based on hunks from a larger patch from Dave Chinner. (First sent on Juli 23rd) Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Signed-off-by: Niv Sardi --- fs/xfs/xfs_ialloc.c | 101 ++++++++++++++++++++++++++++++++-------------------- 1 file changed, 63 insertions(+), 38 deletions(-) (limited to 'fs/xfs/xfs_ialloc.c') diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c index c8a56c529642..efb65fea203c 100644 --- a/fs/xfs/xfs_ialloc.c +++ b/fs/xfs/xfs_ialloc.c @@ -1462,70 +1462,95 @@ xfs_ialloc_log_agi( xfs_trans_log_buf(tp, bp, first, last); } +#ifdef DEBUG +STATIC void +xfs_check_agi_unlinked( + struct xfs_agi *agi) +{ + int i; + + for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) + ASSERT(agi->agi_unlinked[i]); +} +#else +#define xfs_check_agi_unlinked(agi) +#endif + /* * Read in the allocation group header (inode allocation section) */ int -xfs_ialloc_read_agi( - xfs_mount_t *mp, /* file system mount structure */ - xfs_trans_t *tp, /* transaction pointer */ - xfs_agnumber_t agno, /* allocation group number */ - xfs_buf_t **bpp) /* allocation group hdr buf */ +xfs_read_agi( + struct xfs_mount *mp, /* file system mount structure */ + struct xfs_trans *tp, /* transaction pointer */ + xfs_agnumber_t agno, /* allocation group number */ + struct xfs_buf **bpp) /* allocation group hdr buf */ { - xfs_agi_t *agi; /* allocation group header */ - int agi_ok; /* agi is consistent */ - xfs_buf_t *bp; /* allocation group hdr buf */ - xfs_perag_t *pag; /* per allocation group data */ - int error; + struct xfs_agi *agi; /* allocation group header */ + int agi_ok; /* agi is consistent */ + int error; ASSERT(agno != NULLAGNUMBER); - error = xfs_trans_read_buf( - mp, tp, mp->m_ddev_targp, + + error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)), - XFS_FSS_TO_BB(mp, 1), 0, &bp); + XFS_FSS_TO_BB(mp, 1), 0, bpp); if (error) return error; - ASSERT(bp && !XFS_BUF_GETERROR(bp)); + + ASSERT(*bpp && !XFS_BUF_GETERROR(*bpp)); + agi = XFS_BUF_TO_AGI(*bpp); /* * Validate the magic number of the agi block. */ - agi = XFS_BUF_TO_AGI(bp); - agi_ok = - be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC && - XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)); + agi_ok = be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC && + XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) && + be32_to_cpu(agi->agi_seqno) == agno; if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI, XFS_RANDOM_IALLOC_READ_AGI))) { - XFS_CORRUPTION_ERROR("xfs_ialloc_read_agi", XFS_ERRLEVEL_LOW, + XFS_CORRUPTION_ERROR("xfs_read_agi", XFS_ERRLEVEL_LOW, mp, agi); - xfs_trans_brelse(tp, bp); + xfs_trans_brelse(tp, *bpp); return XFS_ERROR(EFSCORRUPTED); } + + XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_AGI, XFS_AGI_REF); + + xfs_check_agi_unlinked(agi); + return 0; +} + +int +xfs_ialloc_read_agi( + struct xfs_mount *mp, /* file system mount structure */ + struct xfs_trans *tp, /* transaction pointer */ + xfs_agnumber_t agno, /* allocation group number */ + struct xfs_buf **bpp) /* allocation group hdr buf */ +{ + struct xfs_agi *agi; /* allocation group header */ + struct xfs_perag *pag; /* per allocation group data */ + int error; + + error = xfs_read_agi(mp, tp, agno, bpp); + if (error) + return error; + + agi = XFS_BUF_TO_AGI(*bpp); pag = &mp->m_perag[agno]; + if (!pag->pagi_init) { pag->pagi_freecount = be32_to_cpu(agi->agi_freecount); pag->pagi_count = be32_to_cpu(agi->agi_count); pag->pagi_init = 1; - } else { - /* - * It's possible for these to be out of sync if - * we are in the middle of a forced shutdown. - */ - ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) || - XFS_FORCED_SHUTDOWN(mp)); - } - -#ifdef DEBUG - { - int i; - - for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++) - ASSERT(agi->agi_unlinked[i]); } -#endif - XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGI, XFS_AGI_REF); - *bpp = bp; + /* + * It's possible for these to be out of sync if + * we are in the middle of a forced shutdown. + */ + ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) || + XFS_FORCED_SHUTDOWN(mp)); return 0; } -- cgit v1.2.3-59-g8ed1b