[PATCH] New testcase to check if fallocate respects RLIMIT_FSIZE or not

["Amit K. Arora" <aarora@linux.vnet.ibm.com>]

On Sat, May 01, 2010 at 06:18:46AM -0400, Christoph Hellwig wrote:
> On Sat, May 01, 2010 at 12:34:26PM +0530, Amit K. Arora wrote:
> > Agreed. How about doing this check in the filesystem specific fallocate
> > inode routines instead ? For example, in ext4 we could do :
> 
> That looks okay - in fact XFS should already have this check because
> it re-uses the setattr implementation to set the size.
> 
> Can you submit an xfstests testcase to verify this behaviour on all
> filesystems?

Here is the new testcase.

I have run this test on a x86_64 box on XFS and ext4 on 2.6.34-rc6. It
passes on XFS, but fails on ext4. Below is the snapshot of results
followed by the testcase itself.

--
Regards,
Amit Arora

Test results:
------------
# ./check 228
FSTYP         -- xfs (non-debug)
PLATFORM      -- Linux/x86_64 elm9m93 2.6.34-rc6

228 0s ...
Ran: 228
Passed all 1 tests
#
# umount /mnt
# mkfs.ext4 /dev/sda4 >/dev/null
mke2fs 1.41.10 (10-Feb-2009)
# ./check 228
FSTYP         -- ext4
PLATFORM      -- Linux/x86_64 elm9m93 2.6.34-rc6

228 0s ... - output mismatch (see 228.out.bad)
--- 228.out	2010-05-03 02:51:24.000000000 -0400
+++ 228.out.bad	2010-05-03 04:27:33.000000000 -0400
@@ -1,2 +1 @@
 QA output created by 228
-File size limit exceeded (core dumped)
Ran: 228
Failures: 228
Failed 1 of 1 tests
#


Here is the test:
----------------
Add a new testcase to the xfstests suite to check if fallocate respects
the limit imposed by RLIMIT_FSIZE (can be set by "ulimit -f XXX") or
not, on a particular filesystem.

Signed-off-by: Amit Arora <aarora@in.ibm.com>

diff -Nuarp xfstests-dev.org/228 xfstests-dev/228
--- xfstests-dev.org/228	1969-12-31 19:00:00.000000000 -0500
+++ xfstests-dev/228	2010-05-03 02:45:10.000000000 -0400
@@ -0,0 +1,79 @@
+#! /bin/bash
+# FS QA Test No. 228
+#
+# Check if fallocate respects RLIMIT_FSIZE 
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2010 IBM Corporation. All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#
+#-----------------------------------------------------------------------
+#
+# creator
+owner=aarora@in.ibm.com
+
+seq=`basename $0`
+echo "QA output created by $seq"
+
+_cleanup()
+{
+	cd /
+	rm -f $tmp.*
+}
+
+here=`pwd`
+tmp=$TEST_DIR/$$
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15 25
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+
+# real QA test starts here
+# generic, but xfs_io's fallocate must work
+_supported_fs generic
+# only Linux supports fallocate
+_supported_os Linux
+
+[ -n "$XFS_IO_PROG" ] || _notrun "xfs_io executable not found"
+
+rm -f $seq.full
+
+# Sanity check to see if fallocate works
+_require_xfs_io_falloc
+
+# Check if we have good enough space available
+avail=`df -P $TEST_DIR | awk 'END {print $4}'`
+[ "$avail" -ge 104000 ] || _notrun "Test device is too small ($avail KiB)"
+
+# Set the FSIZE ulimit to 100MB and check
+ulimit -f 102400
+flim=`ulimit -f`
+[ "$flim" != "unlimited" ] || _notrun "Unable to set FSIZE ulimit"
+[ "$flim" -eq 102400 ] || _notrun "FSIZE ulimit is not correct (100 MB)"
+
+# FSIZE limit is now set to 100 MB.
+# Lets try to preallocate 101 MB. This should fail.
+$XFS_IO_PROG -F -f -c 'falloc 0 101m' $TEST_DIR/ouch
+rm -f $TEST_DIR/ouch
+
+# Lets now try to preallocate 50 MB. This should succeed.
+$XFS_IO_PROG -F -f -c 'falloc 0 50m' $TEST_DIR/ouch
+rm -f $TEST_DIR/ouch
+
+# success, all done
+status=0
+exit
diff -Nuarp xfstests-dev.org/group xfstests-dev/group
--- xfstests-dev.org/group	2010-05-03 02:35:09.000000000 -0400
+++ xfstests-dev/group	2010-05-03 02:45:21.000000000 -0400
@@ -341,3 +341,4 @@ deprecated
 225 auto quick
 226 auto enospc
 227 auto fsr
+228 rw auto prealloc quick