xfs: test rtalloc alignment and math errors

Add a couple of regression tests for "xfs: make sure the rt allocator
doesn't run off the end" and "xfs: ensure that fpunch, fcollapse, and
finsert operations are aligned to rt extent size".

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

tests/xfs/146

@@ -0,0 +1,102 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (c) 2021 Oracle.  All Rights Reserved.
+#
+# FS QA Test No. 146
+#
+# This is a regression test for commit 2a6ca4baed62 ("xfs: make sure the rt
+# allocator doesn't run off the end") which fixes an overflow error in the
+# _near realtime allocator.  If the rt bitmap ends exactly at the end of a
+# block and the number of rt extents is large enough to allow an allocation
+# request larger than the maximum extent size, it's possible that during a
+# large allocation request, the allocator will fail to constrain maxlen on the
+# second run through the loop, and the rt bitmap range check will run right off
+# the end of the rtbitmap file.  When this happens, xfs triggers a verifier
+# error and returns EFSCORRUPTED.
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1    # failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# real QA test starts here
+_supported_fs xfs
+_require_scratch
+_require_realtime
+_require_test_program "punch-alternating"
+
+rm -f $seqres.full
+
+# Format filesystem to get the block size
+_scratch_mkfs > $seqres.full
+_scratch_mount >> $seqres.full
+
+blksz=$(_get_block_size $SCRATCH_MNT)
+rextsize=$($XFS_INFO_PROG $SCRATCH_MNT | grep realtime.*extsz | sed -e 's/^.*extsz=\([0-9]*\).*$/\1/g')
+rextblks=$((rextsize / blksz))
+
+echo "blksz $blksz rextsize $rextsize rextblks $rextblks" >> $seqres.full
+
+_scratch_unmount
+
+# Format filesystem with a realtime volume whose size fits the following:
+# 1. Longer than (XFS MAXEXTLEN * blocksize) bytes so that a large fallocate
+#    request can create a maximally sized data fork extent mapping and then
+#    ask the allocator for even more blocks.
+# 2. Exactly a multiple of (NBBY * blksz * rextsize) bytes.
+
+rtsize1=$((2097151 * blksz))
+rtsize2=$((8 * blksz * rextsize))
+rtsize=$(( $(blockdev --getsz $SCRATCH_RTDEV) * 512 ))
+
+echo "rtsize1 $rtsize1 rtsize2 $rtsize2 rtsize $rtsize" >> $seqres.full
+
+test $rtsize -gt $rtsize1 || \
+	_notrun "scratch rt device too small, need $rtsize1 bytes"
+test $rtsize -gt $rtsize2 || \
+	_notrun "scratch rt device too small, need $rtsize2 bytes"
+
+rtsize=$((rtsize - (rtsize % rtsize2)))
+
+echo "rt size will be $rtsize" >> $seqres.full
+
+_scratch_mkfs -r size=$rtsize >> $seqres.full
+_scratch_mount >> $seqres.full
+
+# Make sure the root directory has rtinherit set so our test file will too
+$XFS_IO_PROG -c 'chattr +t' $SCRATCH_MNT
+
+# Allocate some stuff at the start, to force the first falloc of the ouch file
+# to happen somewhere in the middle of the rt volume
+$XFS_IO_PROG -f -c 'falloc 0 64m' "$SCRATCH_MNT/b"
+$here/src/punch-alternating -i $((rextblks * 2)) -s $((rextblks)) "$SCRATCH_MNT/b"
+
+avail="$(df -P "$SCRATCH_MNT" | awk 'END {print $4}')"1
+toobig="$((avail * 2))"
+
+# falloc the ouch file in the middle of the rt extent to exercise the near
+# allocator in the last step.
+$XFS_IO_PROG -f -c 'falloc 0 1g' "$SCRATCH_MNT/ouch"
+
+# Try to get the near allocator to overflow on an allocation that matches
+# exactly one of the rtsummary size levels.  This should return ENOSPC and
+# not EFSCORRUPTED.
+$XFS_IO_PROG -f -c "falloc 0 ${toobig}k" "$SCRATCH_MNT/ouch"
+
+# success, all done
+status=0
+exit

tests/xfs/146.out

@@ -0,0 +1,2 @@
+QA output created by 146
+fallocate: No space left on device

tests/xfs/147

@@ -0,0 +1,68 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (c) 2021 Oracle.  All Rights Reserved.
+#
+# FS QA Test No. 147
+#
+# Make sure we validate realtime extent size alignment for fallocate modes.
+# This is a regression test for fe341eb151ec ("xfs: ensure that fpunch,
+# fcollapse, and finsert operations are aligned to rt extent size")
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1    # failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# real QA test starts here
+_supported_fs xfs
+_require_scratch
+_require_realtime
+_require_xfs_io_command "fcollapse"
+_require_xfs_io_command "finsert"
+_require_xfs_io_command "funshare"
+_require_xfs_io_command "fzero"
+_require_xfs_io_command "falloc"
+
+rm -f $seqres.full
+
+# Format filesystem with a 256k realtime extent size
+_scratch_mkfs -r extsize=256k > $seqres.full
+_scratch_mount >> $seqres.full
+
+blksz=$(_get_block_size $SCRATCH_MNT)
+rextsize=$($XFS_INFO_PROG $SCRATCH_MNT | grep realtime.*extsz | sed -e 's/^.*extsz=\([0-9]*\).*$/\1/g')
+rextblks=$((rextsize / blksz))
+
+echo "blksz $blksz rextsize $rextsize rextblks $rextblks" >> $seqres.full
+
+# Make sure the root directory has rtinherit set so our test file will too
+$XFS_IO_PROG -c 'chattr +t' $SCRATCH_MNT
+
+sz=$((rextsize * 100))
+range="$((blksz * 3)) $blksz"
+
+for verb in fpunch finsert fcollapse fzero funshare falloc; do
+	echo "test $verb"
+	$XFS_IO_PROG -f -c "falloc 0 $sz" "$SCRATCH_MNT/b"
+	$XFS_IO_PROG -f -c "$verb $range" "$SCRATCH_MNT/b"
+	rm -f "$SCRATCH_MNT/b"
+	_scratch_cycle_mount
+done
+
+# success, all done
+status=0
+exit

tests/xfs/147.out

@@ -0,0 +1,9 @@
+QA output created by 147
+test fpunch
+test finsert
+fallocate: Invalid argument
+test fcollapse
+fallocate: Invalid argument
+test fzero
+test funshare
+test falloc

tests/xfs/group

@@ -143,6 +143,8 @@
 143 auto quick realtime mount
 144 auto quick quota
 145 auto quick quota
+146 auto quick rw realtime
+147 auto quick rw realtime collapse insert unshare zero prealloc
 148 auto quick fuzzers
 149 auto quick growfs
 164 rw pattern auto prealloc quick