factor out xfs_read_agf helper From: Christoph Hellwig 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: Christoph Hellwig Reviewed-by: Dave Chinner Index: linux-2.6-xfs/fs/xfs/xfs_ag.h =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_ag.h 2008-10-01 13:46:50.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_ag.h 2008-10-01 13:48:23.000000000 +0200 @@ -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. Index: linux-2.6-xfs/fs/xfs/xfs_alloc.c =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_alloc.c 2008-10-01 13:47:56.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_alloc.c 2008-10-01 13:49:12.000000000 +0200 @@ -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_agnumber_t agno, /* allocation group number */ - int flags, /* XFS_ALLOC_FLAG_... */ - xfs_buf_t **bpp) /* buffer for the ag freelist header */ +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_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; } Index: linux-2.6-xfs/fs/xfs/xfs_log_recover.c =================================================================== --- linux-2.6-xfs.orig/fs/xfs/xfs_log_recover.c 2008-10-01 13:46:50.000000000 +0200 +++ linux-2.6-xfs/fs/xfs/xfs_log_recover.c 2008-10-01 13:48:23.000000000 +0200 @@ -3998,7 +3998,6 @@ xlog_recover_check_summary( xfs_agi_t *agip; xfs_buf_t *agfbp; xfs_buf_t *agibp; - xfs_daddr_t agfdaddr; xfs_buf_t *sbbp; #ifdef XFS_LOUD_RECOVERY xfs_sb_t *sbp; @@ -4015,21 +4014,18 @@ 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); + freeblks += be32_to_cpu(agfp->agf_freeblks) + + be32_to_cpu(agfp->agf_flcount); + xfs_buf_relse(agfbp); } - 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) {