#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2014 Red Hat, Inc.  All Rights Reserved.
#
# FS QA Test No. generic/030
#
# Test mapped writes against remap+truncate down/up to ensure we get the data
# correctly written. This can expose data corruption bugs on filesystems where
# the block size is smaller than the page size.
#
. ./common/preamble
_begin_fstest auto quick rw

# Import common functions.
. ./common/filter


# Modify as appropriate.
_require_scratch
_require_xfs_io_command "mremap"

testfile=$SCRATCH_MNT/testfile

_scratch_mkfs > /dev/null 2>&1
_scratch_mount

# first case is just truncate down/truncate up to check that the mapped
# write after the truncate up is correctly handled.
$XFS_IO_PROG -t -f \
-c "truncate 5017k"             `# truncate     |       |` \
-c "pwrite -S 0x58 0 5017k"     `# write        |X...XXX|` \
-c "mmap -rw 0 5017k"           `# mmap         |       |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x57 5017k 3k"    `# mwrite       |        WWWWWWWWWWWWWWWW|` \
-c "mremap 5017k "              `# mremap dn    |       |` \
-c "truncate 5017k"             `# mremap dn    |       |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x59 5017k 3k"    `# mwrite       |        YYYYYYYYYYYYYYYY|` \
-c "close"      \
$testfile | _filter_xfs_io

echo "==== Pre-Remount ==="
_hexdump $testfile
_scratch_cycle_mount
echo "==== Post-Remount =="
_hexdump $testfile

rm -f $testfile
_scratch_sync

# second case is to do a mwrite between the truncate to a block on the
# same page we are truncating within the EOF. This checks that a mapped
# write between truncate down and truncate up a further mapped
# write to the same page into the new space doesn't result in data being lost.
$XFS_IO_PROG -t -f \
-c "truncate 5017k"             `# truncate     |       |` \
-c "pwrite -S 0x58 0 5017k"     `# write        |X...XXX|` \
-c "mmap -rw 0 5017k"           `# mmap         |       |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x57 5017k 3k"    `# mwrite       |        WWWWWWWWWWWWWWWW|` \
-c "mremap 5017k "              `# mremap dn    |       |` \
-c "truncate 5017k"             `# mremap dn    |       |` \
-c "mwrite -S 0x5a 5016k 1k"    `# mwrite       |    ZZZ                 |` \
-c "truncate 5020k"             `# truncate up  |                        |` \
-c "mremap -m 5020k"            `# mremap up    |                        |` \
-c "mwrite -S 0x59 5017k 3k"    `# mwrite       |        YYYYYYYYYYYYYYYY|` \
-c "close"      \
$testfile | _filter_xfs_io

echo "==== Pre-Remount ==="
_hexdump $testfile
_scratch_cycle_mount
echo "==== Post-Remount =="
_hexdump $testfile

# third case is the same as the first, but this time on unaligned byte
# boundaries rather than block boundaries. This mimics the exact mmap write
# patterns of the application that exposed the bug in the first place, and
# so is somewhat more complex and has repeated operations in it. 
$XFS_IO_PROG -t -f \
-c "truncate 5136912" \
-c "pwrite -S 0x58 0 5136912" \
-c "mmap -rw 0 5136912" \
-c "mremap 5136912" \
-c "truncate 5136912" \
-c "truncate 5139720" \
-c "mremap -m 5139720" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0 5136912 2808" \
-c "mremap 5136912 " \
-c "truncate 5136912" \
-c "truncate 5139720" \
-c "mremap -m 5139720" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0 5136912 2808" \
-c "mwrite -S 0x59 5136912 2808" \
-c "truncate 5140480" \
-c "mremap 5140480" \
-c "msync -s 0 5140480" \
-c "mremap 5139720" \
-c "munmap" \
-c "close" \
$testfile | _filter_xfs_io

echo "==== Pre-Remount ==="
_hexdump $testfile
_scratch_cycle_mount
echo "==== Post-Remount =="
_hexdump $testfile

status=0
exit

