Re: [RFC 2/3] xfs_io: Add ext4 support to show FS_IOC_FSGETXATTR details

From: Darrick J. Wong
Date: Wed Dec 11 2024 - 13:17:18 EST


On Wed, Dec 11, 2024 at 01:24:03PM +0530, Ojaswin Mujoo wrote:
> Currently with stat we only show FS_IOC_FSGETXATTR details
> if the filesystem is XFS. With extsize support also coming
> to ext4 make sure to show these details when -c "stat" or "statx"
> is used.
>
> No functional changes for filesystems other than ext4.
>
> Signed-off-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx>
> ---
> io/stat.c | 38 +++++++++++++++++++++-----------------
> 1 file changed, 21 insertions(+), 17 deletions(-)
>
> diff --git a/io/stat.c b/io/stat.c
> index 326f2822e276..d06c2186cde4 100644
> --- a/io/stat.c
> +++ b/io/stat.c
> @@ -97,14 +97,14 @@ print_file_info(void)
> file->flags & IO_TMPFILE ? _(",tmpfile") : "");
> }
>
> -static void
> -print_xfs_info(int verbose)
> +static void print_extended_info(int verbose)
> {
> - struct dioattr dio;
> - struct fsxattr fsx, fsxa;
> + struct dioattr dio;
> + struct fsxattr fsx, fsxa;
> + bool is_xfs_fd = platform_test_xfs_fd(file->fd);
>
> - if ((xfsctl(file->name, file->fd, FS_IOC_FSGETXATTR, &fsx)) < 0 ||
> - (xfsctl(file->name, file->fd, XFS_IOC_FSGETXATTRA, &fsxa)) < 0) {
> + if ((ioctl(file->fd, FS_IOC_FSGETXATTR, &fsx)) < 0 ||
> + (is_xfs_fd && (xfsctl(file->name, file->fd, XFS_IOC_FSGETXATTRA, &fsxa) < 0))) {

Urgh... perhaps we should call FS_IOC_FSGETXATTR and if it returns zero
print whatever is returned, no matter what filesystem we think is
feeding us information?

e.g.

if (ioctl(file->fd, FS_IOC_FSGETXATTR, &fsx)) < 0) {
if (is_xfs_fd || (errno != EOPNOTSUPP &&
errno != ENOTTY))
perror("FS_IOC_GETXATTR");
} else {
printf(_("fsxattr.xflags = 0x%x "), fsx.fsx_xflags);
...
}

if (ioctl(file->fd, XFS_IOC_FSGETXATTRA, &fsxa)) < 0) {
if (is_xfs_fd || (errno != EOPNOTSUPP &&
errno != ENOTTY))
perror("XFS_IOC_FSGETXATTRA");
} else {
printf(_("fsxattr.naextents = %u\n"), fsxa.fsx_nextents);
}

That way we don't have to specialcase platform_test_*_fd() for every
other filesystem that might want to return real fsxattr results?
Same idea for DIOINFO.

--D

> perror("FS_IOC_FSGETXATTR");
> } else {
> printf(_("fsxattr.xflags = 0x%x "), fsx.fsx_xflags);
> @@ -113,14 +113,18 @@ print_xfs_info(int verbose)
> printf(_("fsxattr.extsize = %u\n"), fsx.fsx_extsize);
> printf(_("fsxattr.cowextsize = %u\n"), fsx.fsx_cowextsize);
> printf(_("fsxattr.nextents = %u\n"), fsx.fsx_nextents);
> - printf(_("fsxattr.naextents = %u\n"), fsxa.fsx_nextents);
> + if (is_xfs_fd)
> + printf(_("fsxattr.naextents = %u\n"), fsxa.fsx_nextents);
> }
> - if ((xfsctl(file->name, file->fd, XFS_IOC_DIOINFO, &dio)) < 0) {
> - perror("XFS_IOC_DIOINFO");
> - } else {
> - printf(_("dioattr.mem = 0x%x\n"), dio.d_mem);
> - printf(_("dioattr.miniosz = %u\n"), dio.d_miniosz);
> - printf(_("dioattr.maxiosz = %u\n"), dio.d_maxiosz);
> +
> + if (is_xfs_fd) {
> + if ((xfsctl(file->name, file->fd, XFS_IOC_DIOINFO, &dio)) < 0) {
> + perror("XFS_IOC_DIOINFO");
> + } else {
> + printf(_("dioattr.mem = 0x%x\n"), dio.d_mem);
> + printf(_("dioattr.miniosz = %u\n"), dio.d_miniosz);
> + printf(_("dioattr.maxiosz = %u\n"), dio.d_maxiosz);
> + }
> }
> }
>
> @@ -167,10 +171,10 @@ stat_f(
> printf(_("stat.ctime = %s"), ctime(&st.st_ctime));
> }
>
> - if (file->flags & IO_FOREIGN)
> + if (file->flags & IO_FOREIGN && !platform_test_ext4_fd(file->fd))
> return 0;
>
> - print_xfs_info(verbose);
> + print_extended_info(verbose);
>
> return 0;
> }
> @@ -440,10 +444,10 @@ statx_f(
> ctime((time_t *)&stx.stx_btime.tv_sec));
> }
>
> - if (file->flags & IO_FOREIGN)
> + if (file->flags & IO_FOREIGN && !platform_test_ext4_fd(file->fd))
> return 0;
>
> - print_xfs_info(verbose);
> + print_extended_info(verbose);
>
> return 0;
> }
> --
> 2.43.5
>
>