From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
The code to check inobt records against inode clusters is a mess of
poorly named variables and unnecessary parameters. Clean the
unnecessary inode number parameters out of _check_cluster_freemask in
favor of computing them inside the function instead of making the caller
do it. In xchk_iallocbt_check_cluster, rename the variables to make it
more obvious just what chunk_ino and cluster_ino represent.
Add a tracepoint to make it easier to track each inode cluster as we
scrub it.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
fs/xfs/scrub/ialloc.c | 162 ++++++++++++++++++++++++++++++++-----------------
fs/xfs/scrub/trace.h | 45 ++++++++++++++
2 files changed, 151 insertions(+), 56 deletions(-)
diff --git a/fs/xfs/scrub/ialloc.c b/fs/xfs/scrub/ialloc.c
index 9af01ea0258d..2f6c2d7fa3fd 100644
--- a/fs/xfs/scrub/ialloc.c
+++ b/fs/xfs/scrub/ialloc.c
@@ -134,41 +134,70 @@ xchk_iallocbt_freecount(
return hweight64(freemask);
}
-/* Check a particular inode with ir_free. */
+/*
+ * Check that an inode's allocation status matches ir_free in the inobt
+ * record. First we try querying the in-core inode state, and if the inode
+ * isn't loaded we examine the on-disk inode directly.
+ *
+ * Since there can be 1:M and M:1 mappings between inobt records and inode
+ * clusters, we pass in the inode location information as an inobt record;
+ * the index of an inode cluster within the inobt record (as well as the
+ * cluster buffer itself); and the index of the inode within the cluster.
+ *
+ * @irec is the inobt record.
+ * @cluster_base is the inode offset of the cluster within the @irec.
+ * @cluster_bp is the cluster buffer.
+ * @cluster_index is the inode offset within the inode cluster.
+ */
STATIC int
-xchk_iallocbt_check_cluster_freemask(
+xchk_iallocbt_check_cluster_ifree(
struct xchk_btree *bs,
- xfs_ino_t fsino,
- xfs_agino_t chunkino,
- xfs_agino_t clusterino,
struct xfs_inobt_rec_incore *irec,
- struct xfs_buf *bp)
+ unsigned int cluster_base,
+ struct xfs_buf *cluster_bp,
+ unsigned int cluster_index)
{
- struct xfs_dinode *dip;
struct xfs_mount *mp = bs->cur->bc_mp;
- bool inode_is_free = false;
+ struct xfs_dinode *dip;
+ xfs_ino_t fsino;
+ xfs_agino_t agino;
+ unsigned int offset;
+ bool irec_free;
+ bool ino_inuse;
bool freemask_ok;
- bool inuse;
- int error = 0;
+ int error;
if (xchk_should_terminate(bs->sc, &error))
return error;
- dip = xfs_buf_offset(bp, clusterino * mp->m_sb.sb_inodesize);
+ /*
+ * Given an inobt record, an offset of a cluster within the record,
+ * and an offset of an inode within a cluster, compute which fs inode
+ * we're talking about and the offset of the inode record within the
+ * inode buffer.
+ */
+ agino = irec->ir_startino + cluster_base + cluster_index;
+ fsino = XFS_AGINO_TO_INO(mp, bs->cur->bc_private.a.agno, agino);
+ offset = cluster_index * mp->m_sb.sb_inodesize;
+ if (offset >= BBTOB(cluster_bp->b_length)) {
+ xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
+ goto out;
+ }
+ dip = xfs_buf_offset(cluster_bp, offset);
+ irec_free = (irec->ir_free & XFS_INOBT_MASK(cluster_base +
+ cluster_index));
+
if (be16_to_cpu(dip->di_magic) != XFS_DINODE_MAGIC ||
- (dip->di_version >= 3 &&
- be64_to_cpu(dip->di_ino) != fsino + clusterino)) {
+ (dip->di_version >= 3 && be64_to_cpu(dip->di_ino) != fsino)) {
xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
goto out;
}
- if (irec->ir_free & XFS_INOBT_MASK(chunkino + clusterino))
- inode_is_free = true;
- error = xfs_icache_inode_is_allocated(mp, bs->cur->bc_tp,
- fsino + clusterino, &inuse);
+ error = xfs_icache_inode_is_allocated(mp, bs->cur->bc_tp, fsino,
+ &ino_inuse);
if (error == -ENODATA) {
/* Not cached, just read the disk buffer */
- freemask_ok = inode_is_free ^ !!(dip->di_mode);
+ freemask_ok = irec_free ^ !!(dip->di_mode);
if (!bs->sc->try_harder && !freemask_ok)
return -EDEADLOCK;
} else if (error < 0) {
@@ -180,7 +209,7 @@ xchk_iallocbt_check_cluster_freemask(
goto out;
} else {
/* Inode is all there. */
- freemask_ok = inode_is_free ^ inuse;
+ freemask_ok = irec_free ^ ino_inuse;
}
if (!freemask_ok)
xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
@@ -188,43 +217,57 @@ xchk_iallocbt_check_cluster_freemask(
return 0;
}
-/* Check an inode cluster. */
+/*
+ * Check that the holemask and freemask of a hypothetical inode cluster match
+ * what's actually on disk. If sparse inodes are enabled, the cluster does
+ * not actually have to map to inodes if the corresponding holemask bit is set.
+ *
+ * @cluster_base is the first inode in the cluster within the @irec.
+ */
STATIC int
xchk_iallocbt_check_cluster(
struct xchk_btree *bs,
struct xfs_inobt_rec_incore *irec,
- xfs_agino_t agino)
+ unsigned int cluster_base)
{
struct xfs_imap imap;
struct xfs_mount *mp = bs->cur->bc_mp;
struct xfs_dinode *dip;
- struct xfs_buf *bp;
- xfs_ino_t fsino;
+ struct xfs_buf *cluster_bp;
unsigned int nr_inodes;
- xfs_agino_t chunkino;
- xfs_agino_t clusterino;
+ xfs_agnumber_t agno = bs->cur->bc_private.a.agno;
xfs_agblock_t agbno;
- uint16_t holemask;
+ unsigned int cluster_index;
+ uint16_t cluster_mask = 0;
uint16_t ir_holemask;
int error = 0;
- /* Make sure the freemask matches the inode records. */
nr_inodes = min_t(unsigned int, XFS_INODES_PER_CHUNK,
mp->m_inodes_per_cluster);
- fsino = XFS_AGINO_TO_INO(mp, bs->cur->bc_private.a.agno, agino);
- chunkino = agino - irec->ir_startino;
- agbno = XFS_AGINO_TO_AGBNO(mp, agino);
+ /* Map this inode cluster */
+ agbno = XFS_AGINO_TO_AGBNO(mp, irec->ir_startino + cluster_base);
- /* Compute the holemask mask for this cluster. */
- for (clusterino = 0, holemask = 0; clusterino < nr_inodes;
- clusterino += XFS_INODES_PER_HOLEMASK_BIT)
- holemask |= XFS_INOBT_MASK((chunkino + clusterino) /
+ /* Compute a bitmask for this cluster that can be used for holemask. */
+ for (cluster_index = 0;
+ cluster_index < nr_inodes;
+ cluster_index += XFS_INODES_PER_HOLEMASK_BIT)
+ cluster_mask |= XFS_INOBT_MASK((cluster_base + cluster_index) /
XFS_INODES_PER_HOLEMASK_BIT);
+ ir_holemask = (irec->ir_holemask & cluster_mask);
+ imap.im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
+ imap.im_len = XFS_FSB_TO_BB(mp, mp->m_blocks_per_cluster);
+ imap.im_boffset = 0;
+
+ trace_xchk_iallocbt_check_cluster(mp, agno, irec->ir_startino,
+ imap.im_blkno, imap.im_len, cluster_base, nr_inodes,
+ cluster_mask, ir_holemask,
+ XFS_INO_TO_OFFSET(mp, irec->ir_startino +
+ cluster_base));
+
/* The whole cluster must be a hole or not a hole. */
- ir_holemask = (irec->ir_holemask & holemask);
- if (ir_holemask != holemask && ir_holemask != 0) {
+ if (ir_holemask != cluster_mask && ir_holemask != 0) {
xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
return 0;
}
@@ -241,40 +284,47 @@ xchk_iallocbt_check_cluster(
&XFS_RMAP_OINFO_INODES);
/* Grab the inode cluster buffer. */
- imap.im_blkno = XFS_AGB_TO_DADDR(mp, bs->cur->bc_private.a.agno, agbno);
- imap.im_len = XFS_FSB_TO_BB(mp, mp->m_blocks_per_cluster);
- imap.im_boffset = 0;
-
- error = xfs_imap_to_bp(mp, bs->cur->bc_tp, &imap, &dip, &bp, 0, 0);
+ error = xfs_imap_to_bp(mp, bs->cur->bc_tp, &imap, &dip, &cluster_bp,
+ 0, 0);
if (!xchk_btree_xref_process_error(bs->sc, bs->cur, 0, &error))
- return 0;
+ return error;
- /* Which inodes are free? */
- for (clusterino = 0; clusterino < nr_inodes; clusterino++) {
- error = xchk_iallocbt_check_cluster_freemask(bs, fsino,
- chunkino, clusterino, irec, bp);
+ /* Check free status of each inode within this cluster. */
+ for (cluster_index = 0; cluster_index < nr_inodes; cluster_index++) {
+ error = xchk_iallocbt_check_cluster_ifree(bs, irec,
+ cluster_base, cluster_bp, cluster_index);
if (error)
break;
}
- xfs_trans_brelse(bs->cur->bc_tp, bp);
+ xfs_trans_brelse(bs->cur->bc_tp, cluster_bp);
return error;
}
-/* Make sure the free mask is consistent with what the inodes think. */
+/*
+ * For all the inode clusters that could map to this inobt record, make sure
+ * that the holemask makes sense and that the allocation status of each inode
+ * matches the freemask.
+ */
STATIC int
-xchk_iallocbt_check_freemask(
+xchk_iallocbt_check_clusters(
struct xchk_btree *bs,
struct xfs_inobt_rec_incore *irec)
{
- struct xfs_mount *mp = bs->cur->bc_mp;
- xfs_agino_t agino;
+ unsigned int cluster_base;
int error = 0;
- for (agino = irec->ir_startino;
- agino < irec->ir_startino + XFS_INODES_PER_CHUNK;
- agino += mp->m_blocks_per_cluster * mp->m_sb.sb_inopblock) {
- error = xchk_iallocbt_check_cluster(bs, irec, agino);
+ /*
+ * For the common case where this inobt record maps to multiple inode
+ * clusters this will call _check_cluster for each cluster.
+ *
+ * For the case that multiple inobt records map to a single cluster,
+ * this will call _check_cluster once.
+ */
+ for (cluster_base = 0;
+ cluster_base < XFS_INODES_PER_CHUNK;
+ cluster_base += bs->sc->mp->m_inodes_per_cluster) {
+ error = xchk_iallocbt_check_cluster(bs, irec, cluster_base);
if (error)
break;
}
@@ -431,7 +481,7 @@ xchk_iallocbt_rec(
xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
check_freemask:
- error = xchk_iallocbt_check_freemask(bs, &irec);
+ error = xchk_iallocbt_check_clusters(bs, &irec);
if (error)
goto out;
diff --git a/fs/xfs/scrub/trace.h b/fs/xfs/scrub/trace.h
index 8344b14031ef..3c83e8b3b39c 100644
--- a/fs/xfs/scrub/trace.h
+++ b/fs/xfs/scrub/trace.h
@@ -545,6 +545,51 @@ TRACE_EVENT(xchk_xref_error,
__entry->ret_ip)
);
+TRACE_EVENT(xchk_iallocbt_check_cluster,
+ TP_PROTO(struct xfs_mount *mp, xfs_agnumber_t agno,
+ xfs_agino_t startino, xfs_daddr_t map_daddr,
+ unsigned short map_len, unsigned int chunk_ino,
+ unsigned int nr_inodes, uint16_t cluster_mask,
+ uint16_t holemask, unsigned int cluster_ino),
+ TP_ARGS(mp, agno, startino, map_daddr, map_len, chunk_ino, nr_inodes,
+ cluster_mask, holemask, cluster_ino),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(xfs_agnumber_t, agno)
+ __field(xfs_agino_t, startino)
+ __field(xfs_daddr_t, map_daddr)
+ __field(unsigned short, map_len)
+ __field(unsigned int, chunk_ino)
+ __field(unsigned int, nr_inodes)
+ __field(unsigned int, cluster_ino)
+ __field(uint16_t, cluster_mask)
+ __field(uint16_t, holemask)
+ ),
+ TP_fast_assign(
+ __entry->dev = mp->m_super->s_dev;
+ __entry->agno = agno;
+ __entry->startino = startino;
+ __entry->map_daddr = map_daddr;
+ __entry->map_len = map_len;
+ __entry->chunk_ino = chunk_ino;
+ __entry->nr_inodes = nr_inodes;
+ __entry->cluster_mask = cluster_mask;
+ __entry->holemask = holemask;
+ __entry->cluster_ino = cluster_ino;
+ ),
+ TP_printk("dev %d:%d agno %d startino %u daddr 0x%llx len %d chunkino %u nr_inodes %u cluster_mask 0x%x holemask 0x%x cluster_ino %u",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->agno,
+ __entry->startino,
+ __entry->map_daddr,
+ __entry->map_len,
+ __entry->chunk_ino,
+ __entry->nr_inodes,
+ __entry->cluster_mask,
+ __entry->holemask,
+ __entry->cluster_ino)
+)
+
/* repair tracepoints */
#if IS_ENABLED(CONFIG_XFS_ONLINE_REPAIR)
