xfs: test metapath repairs

Functional testing for metadir path checking and repairs.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zorro Lang <zlang@kernel.org>

diff --git a/tests/xfs/817 b/tests/xfs/817
new file mode 100755 (executable)
index 0000000..2cba5d4
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+++ b/tests/xfs/817
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+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2023-2025 Oracle.  All Rights Reserved.
+#
+# FS QA Test No. 817
+#
+# Functional test of using online repair to fix metadir paths.
+#
+. ./common/preamble
+_begin_fstest auto online_repair
+
+. ./common/filter
+. ./common/inject
+. ./common/fuzzy
+. ./common/quota
+
+_require_xfs_db_command "link"
+_require_xfs_db_command "unlink"
+_require_scratch
+_require_xfs_stress_online_repair
+
+prepare_fs() {
+       # Format filesystem
+       _scratch_mkfs | _filter_mkfs 2> $tmp.mkfs >> $seqres.full
+       _scratch_mount
+
+       _require_xfs_has_feature "$SCRATCH_MNT" rmapbt
+       _require_xfs_has_feature "$SCRATCH_MNT" realtime
+       _require_xfs_has_feature "$SCRATCH_MNT" metadir
+       _require_xfs_has_feature "$SCRATCH_MNT" parent
+
+       root_inum="$(stat -c '%i' $SCRATCH_MNT)"
+       __stress_scrub_check_commands "%dir%" '' '' 'scrub metapath'
+       _scratch_unmount
+
+       # Stash the /rtgroups inode number and gen
+       rt_metadir_inum=$(_scratch_xfs_get_metadata_field v3.inumber 'path -m /rtgroups')
+       rt_metadir_gen=$(_scratch_xfs_get_metadata_field core.gen 'path -m /rtgroups')
+
+       # Stash the /rtgroups/0.rmap inode number and gen
+       rbm_inum=$(_scratch_xfs_get_metadata_field v3.inumber 'path -m /rtgroups/0.rmap')
+       rbm_gen=$(_scratch_xfs_get_metadata_field core.gen 'path -m /rtgroups/0.rmap')
+
+       # Fuzz parent pointer in rtgroup 0 rmap file
+       _scratch_xfs_db -x \
+               -c 'path -m /rtgroups/0.rmap' \
+               -c "write -d a.sfattr.list[0].parent_dir.inumber $root_inum" >> $seqres.full
+}
+
+simple_online_repair() {
+       echo "check /rtgroups dir" | _tee_kernlog
+       $XFS_IO_PROG -c "scrub directory $rt_metadir_inum $rt_metadir_gen" $SCRATCH_MNT
+
+       echo "check /rtgroups/0.rmap pptr" | _tee_kernlog
+       $XFS_IO_PROG -c "scrub parent $rbm_inum $rbm_gen" $SCRATCH_MNT
+
+       echo "check /rtgroups/0.rmap metapath" | _tee_kernlog
+       $XFS_IO_PROG -c "scrub metapath rtrmapbt 0" $SCRATCH_MNT
+
+       echo "check nlinks" | _tee_kernlog
+       $XFS_IO_PROG -c "scrub nlinks" $SCRATCH_MNT
+
+       # Destroying a metadir path (e.g. /rtgroups/0.rmap) cannot be done
+       # offline because then the mount will fail.  Hence we must use a
+       # specific sequence of online repairs to remove the metadir path link.
+       # Only then can we use the metapath scrubber to restore the link.
+
+       # Force repair the parent directory.  Since /rtgroups/0.rmap has a bad
+       # parent pointer, the "0.rmap" entry in /rtgroups will not be created.
+       echo "fix /rtgroups dir" | _tee_kernlog
+       $XFS_IO_PROG -x -c "repair -R directory $rt_metadir_inum $rt_metadir_gen" $SCRATCH_MNT
+
+       # Force repair the parent pointer.  Since the "0.rmap" entry in
+       # /rtgroups no longer exists and no other directories count the
+       # rtgroup 0 rmap as a parent, this will fail cross-referencing after
+       # the repair.
+       echo "fix /rtgroups/0.rmap pptr" | _tee_kernlog
+       $XFS_IO_PROG -x -c "repair -R parent $rbm_inum $rbm_gen" $SCRATCH_MNT
+
+       # Now that we've completely erased the /rtgroups/0.rmap path, check
+       # that the link is indeed lost, and restore the link.
+       echo "fix /rtgroups/0.rmap metapath" | _tee_kernlog
+       $XFS_IO_PROG -x -c "repair metapath rtrmapbt 0" $SCRATCH_MNT
+
+       # Make sure we're not missing any link count
+       echo "fix nlinks" | _tee_kernlog
+       $XFS_IO_PROG -x -c "repair nlinks" $SCRATCH_MNT
+}
+
+echo Part 1: Use raw ioctls to detect the error and fix it.
+prepare_fs
+_scratch_mount
+simple_online_repair
+_check_scratch_fs
+_scratch_unmount
+
+echo Part 2: Use xfs_scrub to detect the error and fix it.
+prepare_fs
+_scratch_mount
+echo "fix with xfs_scrub" | _tee_kernlog
+_scratch_scrub &>> $seqres.full
+echo "xfs_scrub returned $?" >> $seqres.full
+_check_scratch_fs
+_scratch_unmount
+
+echo Part 3: Use xfs_repair to detect the error and fix it.
+prepare_fs
+echo "fix with xfs_repair" | _tee_kernlog
+echo repair?? >> $seqres.full
+_scratch_xfs_repair &>> $seqres.full
+echo "xfs_repair returned $?" >> $seqres.full
+_scratch_mount
+_check_scratch_fs
+_scratch_unmount
+
+echo "done with test" | _tee_kernlog
+# success, all done
+status=0
+exit

diff --git a/tests/xfs/817.out b/tests/xfs/817.out
new file mode 100644 (file)
index 0000000..4437d68
--- /dev/null
+++ b/tests/xfs/817.out
@@ -0,0 +1,19 @@
+QA output created by 817
+Part 1: Use raw ioctls to detect the error and fix it.
+check /rtgroups dir
+Corruption detected during cross-referencing.
+check /rtgroups/0.rmap pptr
+Corruption detected during cross-referencing.
+check /rtgroups/0.rmap metapath
+check nlinks
+fix /rtgroups dir
+fix /rtgroups/0.rmap pptr
+Corruption remains.
+Corruption still detected during cross-referencing.
+fix /rtgroups/0.rmap metapath
+fix nlinks
+Part 2: Use xfs_scrub to detect the error and fix it.
+fix with xfs_scrub
+Part 3: Use xfs_repair to detect the error and fix it.
+fix with xfs_repair
+done with test