2021-12-20 20:41:08

by Theodore Ts'o

[permalink] [raw]
Subject: [PATCH] ext4/033: test EXT4_IOC_RESIZE_FS by calling the ioctl directly

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 <[email protected]>
Signed-off-by: Theodore Ts'o <[email protected]>
---
.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
+
+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



2022-01-05 15:57:56

by Zorro Lang

[permalink] [raw]
Subject: Re: [PATCH] ext4/033: test EXT4_IOC_RESIZE_FS by calling the ioctl directly

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 <[email protected]>
> Signed-off-by: Theodore Ts'o <[email protected]>
> ---
> .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
>


2022-01-05 16:06:29

by Zorro Lang

[permalink] [raw]
Subject: Re: [PATCH] ext4/033: test EXT4_IOC_RESIZE_FS by calling the ioctl directly

On Wed, Jan 05, 2022 at 11:57:43PM +0800, Zorro Lang wrote:
> 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 <[email protected]>
> > Signed-off-by: Theodore Ts'o <[email protected]>
> > ---
> > .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 :)

Oh, I just noticed that this patch has been merged. I have no idea why this email become
*unread* status in my mutt, cause I thought it's a new patch. Please ignore this review.

>
> 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
> >


2022-01-05 20:04:22

by Theodore Ts'o

[permalink] [raw]
Subject: Re: [PATCH] ext4/033: test EXT4_IOC_RESIZE_FS by calling the ioctl directly

On Thu, Jan 06, 2022 at 12:06:19AM +0800, Zorro Lang wrote:
> > 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 :)

We're not depending on ext2fs/ext2_fs.h and hence the e2fsprogs-devel
(or libext2fs-dev package if you're using Debian/Ubuntu) anywhere else
in the xfstests-dev. It's not like the code points for
EXT4_IOC_RESIZE_FS are going to change, so we just use constructs
like:

#ifndef EXT4_IOC_RESIZE_FS
#define EXT4_IOC_RESIZE_FS _IOW('f', 16, __u64)
#endif

in xfstests-dev/src/*.c as needed.

There's no real upside in adding a dependency which makes it harder
for developers to compile xfstests. (Trivia note: I created
xfstests-bld several years ago because back then, Debian didn't
include some of the internal header files from xfsprogs which xfstests
needed.)

Cheers,

- Ted

2022-01-06 02:35:18

by Zorro Lang

[permalink] [raw]
Subject: Re: [PATCH] ext4/033: test EXT4_IOC_RESIZE_FS by calling the ioctl directly

On Wed, Jan 05, 2022 at 03:02:58PM -0500, Theodore Ts'o wrote:
> On Thu, Jan 06, 2022 at 12:06:19AM +0800, Zorro Lang wrote:
> > > 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 :)
>
> We're not depending on ext2fs/ext2_fs.h and hence the e2fsprogs-devel
> (or libext2fs-dev package if you're using Debian/Ubuntu) anywhere else
> in the xfstests-dev. It's not like the code points for
> EXT4_IOC_RESIZE_FS are going to change, so we just use constructs
> like:
>
> #ifndef EXT4_IOC_RESIZE_FS
> #define EXT4_IOC_RESIZE_FS _IOW('f', 16, __u64)
> #endif
>
> in xfstests-dev/src/*.c as needed.
>
> There's no real upside in adding a dependency which makes it harder
> for developers to compile xfstests. (Trivia note: I created
> xfstests-bld several years ago because back then, Debian didn't
> include some of the internal header files from xfsprogs which xfstests
> needed.)

Thanks for your kindly explanation.

>
> Cheers,
>
> - Ted
>