[PATCH 3/5] generic/xxx: Add MMAP CoW test for 'hole' case

[Shiyang Ruan <ruansy.fnst@fujitsu.com>]

Check what happens if we MMAP CoW blocks 2-4 of a page's worth of blocks when
the second block is a hole.  (MMAP version of generic/218,220)

Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
---
 tests/generic/902     | 70 +++++++++++++++++++++++++++++++++++++++++++
 tests/generic/902.out |  6 ++++
 2 files changed, 76 insertions(+)
 create mode 100755 tests/generic/902
 create mode 100644 tests/generic/902.out

diff --git a/tests/generic/902 b/tests/generic/902
new file mode 100755
index 00000000..3fbf6143
--- /dev/null
+++ b/tests/generic/902
@@ -0,0 +1,70 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# FS QA Test No. xxx
+#
+# See what happens if we MMAP CoW blocks 2-4 of a page's worth of blocks when
+# the second block is a hole.  (MMAP version of generic/218,220)
+#
+# This test is dependent on the system page size, so we cannot use md5 in
+# the golden output; we can only compare to a check file.
+#
+. ./common/preamble
+_begin_fstest auto quick clone
+
+# Override the default cleanup function.
+_cleanup()
+{
+    cd /
+    rm -rf $tmp.* $testdir
+}
+
+# Import common functions.
+. ./common/filter
+. ./common/reflink
+
+# real QA test starts here
+_require_scratch_reflink
+_require_xfs_io_command "falloc"
+
+pagesz=$(getconf PAGE_SIZE)
+blksz=$((pagesz / 4))
+
+echo "Format and mount"
+_scratch_mkfs_blocksized $blksz > $seqres.full 2>&1
+_scratch_mount >> $seqres.full 2>&1
+
+testdir=$SCRATCH_MNT/test-$seq
+mkdir $testdir
+
+real_blksz=$(_get_file_block_size $testdir)
+test $real_blksz != $blksz && _notrun "Failed to format with small blocksize."
+
+echo "Create the original files"
+_pwrite_byte 0x61 0 $pagesz $testdir/file1 >> $seqres.full
+
+$XFS_IO_PROG -f -c "truncate $pagesz" $testdir/file2 >> $seqres.full
+$XFS_IO_PROG -f -c "truncate $pagesz" $testdir/file2.chk >> $seqres.full
+
+_reflink_range $testdir/file1 $blksz $testdir/file2 $((blksz * 2)) $blksz >> $seqres.full
+_pwrite_byte 0x61 $((blksz * 2)) $blksz $testdir/file2.chk >> $seqres.full
+_scratch_cycle_mount
+
+echo "Compare files"
+! cmp -s $testdir/file1 $testdir/file2 || _fail "file1 and file2 don't match."
+cmp -s $testdir/file2 $testdir/file2.chk || _fail "file2 and file2.chk don't match."
+
+echo "CoW and unmount"
+$XFS_IO_PROG -f -c "mmap 0 $pagesz" \
+    -c "mwrite -S 0x63 $((blksz + 17)) $((blksz * 3 - 34))" $testdir/file2 >> $seqres.full
+$XFS_IO_PROG -f -c "mmap 0 $pagesz" \
+    -c "mwrite -S 0x63 $((blksz + 17)) $((blksz * 3 - 34))" $testdir/file2.chk >> $seqres.full
+_scratch_cycle_mount
+
+echo "Compare files"
+! cmp -s $testdir/file1 $testdir/file2 || _fail "file1 and file2 don't match."
+cmp -s $testdir/file2 $testdir/file2.chk || _fail "file2 and file2.chk don't match."
+
+# success, all done
+status=0
+exit
diff --git a/tests/generic/902.out b/tests/generic/902.out
new file mode 100644
index 00000000..4fb8b6cb
--- /dev/null
+++ b/tests/generic/902.out
@@ -0,0 +1,6 @@
+QA output created by 902
+Format and mount
+Create the original files
+Compare files
+CoW and unmount
+Compare files
-- 
2.33.0