On Mon, Dec 20, 2021 at 03:40:59PM -0500, Theodore Ts'o wrote: > E2fsprogs commits 4ea80d031c7e ("resize2fs: adjust new size of the > file system to allow a successful resize") and 50088b1996cc > ("resize2fs: attempt to keep the # of inodes valid by removing the > last bg") will automatically reduce the requested new size of the file > system by up to a single block group to avoid overflowing the 32-bit > inode count. This interferes with ext4/033's test of kernel commit > 4f2f76f75143 ("ext4: Forbid overflowing inode count when # resizing".) > > Address this by creating a new test program, ext4_resize which calls > the EXT4_IOC_RESIZE_FS ioctl directly so we can correctly test the > kernel's online resize code. > > Reported-by: Eric Whitney <enwlinux@xxxxxxxxx> > Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> > --- > .gitignore | 1 + > src/Makefile | 2 +- > src/ext4_resize.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++ > tests/ext4/033 | 16 ++++++++++----- > 4 files changed, 63 insertions(+), 6 deletions(-) > create mode 100644 src/ext4_resize.c > > diff --git a/.gitignore b/.gitignore > index 9e6d2fd5..65b93307 100644 > --- a/.gitignore > +++ b/.gitignore > @@ -77,6 +77,7 @@ tags > /src/dirperf > /src/dirstress > /src/e4compact > +/src/ext4_resize > /src/fault > /src/feature > /src/fiemap-tester > diff --git a/src/Makefile b/src/Makefile > index 25ab061d..1737ed0e 100644 > --- a/src/Makefile > +++ b/src/Makefile > @@ -31,7 +31,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ > dio-invalidate-cache stat_test t_encrypted_d_revalidate \ > attr_replace_test swapon mkswap t_attr_corruption t_open_tmpfiles \ > fscrypt-crypt-util bulkstat_null_ocount splice-test chprojid_fail \ > - detached_mounts_propagation > + detached_mounts_propagation ext4_resize > > EXTRA_EXECS = dmerror fill2attr fill2fs fill2fs_check scaleread.sh \ > btrfs_crc32c_forged_name.py > diff --git a/src/ext4_resize.c b/src/ext4_resize.c > new file mode 100644 > index 00000000..1ac51e6f > --- /dev/null > +++ b/src/ext4_resize.c > @@ -0,0 +1,50 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +/* > + * Test program which uses the raw ext4 resize_fs ioctl directly. > + */ > + > +#include <stdio.h> > +#include <fcntl.h> > +#include <errno.h> > +#include <unistd.h> > +#include <stdint.h> > +#include <stdlib.h> > +#include <sys/ioctl.h> > +#include <sys/mount.h> > + > +typedef unsigned long long __u64; > + > +#ifndef EXT4_IOC_RESIZE_FS > +#define EXT4_IOC_RESIZE_FS _IOW('f', 16, __u64) > +#endif This patch looks good to me, I just want to ask if we'd better to try to include ext2fs/ext2fs.h at here? And of course, check it in configure.ac. The EXT4_IOC_RESIZE_FS looks like defined in ext2fs/ext2_fs.h which comes from e2fsprogs-devel package. I can't find this definition from kernel-hearders package. As you're the expert of this part, please correct me if it's wrong :) Thanks, Zorro > + > +int main(int argc, char **argv) > +{ > + __u64 new_size; > + int error, fd; > + char *tmp = NULL; > + > + if (argc != 3) { > + fputs("insufficient arguments\n", stderr); > + return 1; > + } > + fd = open(argv[1], O_RDONLY); > + if (!fd) { > + perror(argv[1]); > + return 1; > + } > + > + new_size = strtoull(argv[2], &tmp, 10); > + if ((errno) || (*tmp != '\0')) { > + fprintf(stderr, "%s: invalid new size\n", argv[0]); > + return 1; > + } > + > + error = ioctl(fd, EXT4_IOC_RESIZE_FS, &new_size); > + if (error < 0) { > + perror("EXT4_IOC_RESIZE_FS"); > + return 1; > + } > + return 0; > +} > diff --git a/tests/ext4/033 b/tests/ext4/033 > index 1bc14c03..22041a17 100755 > --- a/tests/ext4/033 > +++ b/tests/ext4/033 > @@ -5,7 +5,8 @@ > # FS QA Test 033 > # > # Test s_inodes_count overflow for huge filesystems. This bug was fixed > -# by commit "ext4: Forbid overflowing inode count when resizing". > +# by commit 4f2f76f75143 ("ext4: Forbid overflowing inode count when > +# resizing".) > # > . ./common/preamble > _begin_fstest auto ioctl resize > @@ -28,7 +29,9 @@ _supported_fs ext4 > _require_scratch_nocheck > _require_dmhugedisk > _require_dumpe2fs > -_require_command "$RESIZE2FS_PROG" resize2fs > +_require_test_program ext4_resize > + > +EXT4_RESIZE=$here/src/ext4_resize > > # Figure out whether device is large enough > devsize=$(blockdev --getsize64 $SCRATCH_DEV) > @@ -68,7 +71,8 @@ $DUMPE2FS_PROG -h $DMHUGEDISK_DEV >> $seqres.full 2>&1 > > # This should fail, s_inodes_count would just overflow! > echo "Resizing to inode limit + 1..." > -$RESIZE2FS_PROG $DMHUGEDISK_DEV $((limit_groups*group_blocks)) >> $seqres.full 2>&1 > +echo $EXT4_RESIZE $SCRATCH_MNT $((limit_groups*group_blocks)) >> $seqres.full 2>&1 > +$EXT4_RESIZE $SCRATCH_MNT $((limit_groups*group_blocks)) >> $seqres.full 2>&1 > if [ $? -eq 0 ]; then > echo "Resizing succeeded but it should fail!" > exit > @@ -76,7 +80,8 @@ fi > > # This should succeed, we are maxing out inodes > echo "Resizing to max group count..." > -$RESIZE2FS_PROG $DMHUGEDISK_DEV $(((limit_groups-1)*group_blocks)) >> $seqres.full 2>&1 > +echo $EXT4_RESIZE $SCRATCH_MNT $(((limit_groups-1)*group_blocks)) >> $seqres.full 2>&1 > +$EXT4_RESIZE $SCRATCH_MNT $(((limit_groups-1)*group_blocks)) >> $seqres.full 2>&1 > if [ $? -ne 0 ]; then > echo "Resizing failed!" > exit > @@ -87,7 +92,8 @@ $DUMPE2FS_PROG -h $DMHUGEDISK_DEV >> $seqres.full 2>&1 > > # This should fail, s_inodes_count would overflow by quite a bit! > echo "Resizing to device size..." > -$RESIZE2FS_PROG $DMHUGEDISK_DEV >> $seqres.full 2>&1 > +echo $EXT4_RESIZE $SCRATCH_MNT $(((limit_groups + 16)*group_blocks)) >> $seqres.full 2>&1 > +$EXT4_RESIZE $SCRATCH_MNT $(((limit_groups + 16)*group_blocks)) >> $seqres.full 2>&1 > if [ $? -eq 0 ]; then > echo "Resizing succeeded but it should fail!" > exit > -- > 2.31.0 >