From 04b21e41be4e04cef16c30ced6d6c5cfb2fec364 Mon Sep 17 00:00:00 2001 From: Brian Foster Date: Fri, 31 Jul 2015 11:03:49 +1000 Subject: [PATCH] metadump: support sparse inode records xfs_metadump currently uses mp->m_ialloc_blks sized buffers to copy inode chunks. If a filesystem supports sparse inodes, some clusters within inode chunks can point to arbitrary data. If the buffer used to read inodes includes these sparse clusters, inode read verification fails and prints filesystem corruption warnings. Update copy_inode_chunks() to support using a cluster sized buffer to read a full inode chunk in multiple iterations if sparse inodes is enabled. For each cluster read, check whether the first inode in the cluster is sparse and skip the cluster if so. This is safe because sparse records are allocated at cluster granularity. Signed-off-by: Brian Foster Reviewed-by: Dave Chinner Signed-off-by: Dave Chinner --- db/metadump.c | 84 ++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 60 insertions(+), 24 deletions(-) diff --git a/db/metadump.c b/db/metadump.c index 0398bfa6f..deb7437dd 100644 --- a/db/metadump.c +++ b/db/metadump.c @@ -2115,13 +2115,43 @@ copy_inode_chunk( xfs_agino_t agino; int off; xfs_agblock_t agbno; + xfs_agblock_t end_agbno; int i; int rval = 0; + int blks_per_buf; + int inodes_per_buf; + int ioff; agino = be32_to_cpu(rp->ir_startino); agbno = XFS_AGINO_TO_AGBNO(mp, agino); + end_agbno = agbno + mp->m_ialloc_blks; off = XFS_INO_TO_OFFSET(mp, agino); + /* + * If the fs supports sparse inode records, we must process inodes a + * cluster at a time because that is the sparse allocation granularity. + * Otherwise, we risk CRC corruption errors on reads of inode chunks. + * + * Also make sure that that we don't process more than the single record + * we've been passed (large block sizes can hold multiple inode chunks). + */ + if (xfs_sb_version_hassparseinodes(&mp->m_sb)) + blks_per_buf = xfs_icluster_size_fsb(mp); + else + blks_per_buf = mp->m_ialloc_blks; + inodes_per_buf = min(blks_per_buf << mp->m_sb.sb_inopblog, + XFS_INODES_PER_CHUNK); + + /* + * Sanity check that we only process a single buffer if ir_startino has + * a buffer offset. A non-zero offset implies that the entire chunk lies + * within a block. + */ + if (off && inodes_per_buf != XFS_INODES_PER_CHUNK) { + print_warning("bad starting inode offset %d", off); + return 0; + } + if (agino == 0 || agino == NULLAGINO || !valid_bno(agno, agbno) || !valid_bno(agno, XFS_AGINO_TO_AGBNO(mp, agino + XFS_INODES_PER_CHUNK - 1))) { @@ -2148,35 +2178,41 @@ copy_inode_chunk( } push_cur(); - set_cur(&typtab[TYP_INODE], XFS_AGB_TO_DADDR(mp, agno, agbno), - XFS_FSB_TO_BB(mp, mp->m_ialloc_blks), - DB_RING_IGN, NULL); - if (iocur_top->data == NULL) { - print_warning("cannot read inode block %u/%u", agno, agbno); - rval = !stop_on_read_error; - goto pop_out; - } + ioff = 0; + while (agbno < end_agbno && ioff < XFS_INODES_PER_CHUNK) { + if (xfs_inobt_is_sparse_disk(rp, ioff)) + goto next_bp; + + set_cur(&typtab[TYP_INODE], XFS_AGB_TO_DADDR(mp, agno, agbno), + XFS_FSB_TO_BB(mp, blks_per_buf), DB_RING_IGN, NULL); + if (iocur_top->data == NULL) { + print_warning("cannot read inode block %u/%u", + agno, agbno); + rval = !stop_on_read_error; + goto pop_out; + } - /* - * scan through inodes and copy any btree extent lists, directory - * contents and extended attributes. - */ - for (i = 0; i < XFS_INODES_PER_CHUNK; i++) { - xfs_dinode_t *dip; + for (i = 0; i < inodes_per_buf; i++) { + xfs_dinode_t *dip; - dip = (xfs_dinode_t *)((char *)iocur_top->data + - ((off + i) << mp->m_sb.sb_inodelog)); + dip = (xfs_dinode_t *)((char *)iocur_top->data + + ((off + i) << mp->m_sb.sb_inodelog)); - /* process_inode handles free inodes, too */ - if (!process_inode(agno, agino + i, dip, - XFS_INOBT_IS_FREE_DISK(rp, i))) - goto pop_out; - } + /* process_inode handles free inodes, too */ + if (!process_inode(agno, agino + ioff + i, dip, + XFS_INOBT_IS_FREE_DISK(rp, i))) + goto pop_out; - if (write_buf(iocur_top)) - goto pop_out; + inodes_copied++; + } - inodes_copied += XFS_INODES_PER_CHUNK; + if (write_buf(iocur_top)) + goto pop_out; + +next_bp: + agbno += blks_per_buf; + ioff += inodes_per_buf; + } if (show_progress) print_progress("Copied %u of %u inodes (%u of %u AGs)", -- 2.47.2