On 1/23/20 6:17 PM, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>
> Make sure the root inode gets created where repair thinks it should be
> created.
Actual mkfs-time location calculation is still completely separate from
the code in xfs_ialloc_calc_rootino though, right? Maybe there's nothing
to do about that.
I mostly find myself wondering what a user will do next if this check fails.
Assuming we trust xfs_ialloc_calc_rootino though, this seems fine.
Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxx>
-Eric
> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> ---
> libxfs/libxfs_api_defs.h | 1 +
> mkfs/xfs_mkfs.c | 39 +++++++++++++++++++++++++++++++++------
> 2 files changed, 34 insertions(+), 6 deletions(-)
>
>
> diff --git a/libxfs/libxfs_api_defs.h b/libxfs/libxfs_api_defs.h
> index cc7304ad..9ede0125 100644
> --- a/libxfs/libxfs_api_defs.h
> +++ b/libxfs/libxfs_api_defs.h
> @@ -172,6 +172,7 @@
>
> #define xfs_ag_init_headers libxfs_ag_init_headers
> #define xfs_buf_delwri_submit libxfs_buf_delwri_submit
> +#define xfs_ialloc_calc_rootino libxfs_ialloc_calc_rootino
>
> #define xfs_refcountbt_calc_reserves libxfs_refcountbt_calc_reserves
> #define xfs_finobt_calc_reserves libxfs_finobt_calc_reserves
> diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
> index 784fe6a9..91a25bf5 100644
> --- a/mkfs/xfs_mkfs.c
> +++ b/mkfs/xfs_mkfs.c
> @@ -3549,6 +3549,38 @@ rewrite_secondary_superblocks(
> libxfs_writebuf(buf, LIBXFS_EXIT_ON_FAILURE);
> }
>
> +static void
> +check_root_ino(
> + struct xfs_mount *mp)
> +{
> + xfs_ino_t ino;
> +
> + if (XFS_INO_TO_AGNO(mp, mp->m_sb.sb_rootino) != 0) {
> + fprintf(stderr,
> + _("%s: root inode created in AG %u, not AG 0\n"),
> + progname, XFS_INO_TO_AGNO(mp, mp->m_sb.sb_rootino));
> + exit(1);
> + }
> +
> + /*
> + * The superblock points to the root directory inode, but xfs_repair
> + * expects to find the root inode in a very specific location computed
> + * from the filesystem geometry for an extra level of verification.
> + *
> + * Fail the format immediately if those assumptions ever break, because
> + * repair will toss the root directory.
> + */
> + ino = libxfs_ialloc_calc_rootino(mp, mp->m_sb.sb_unit);
> + if (mp->m_sb.sb_rootino != ino) {
> + fprintf(stderr,
> + _("%s: root inode (%llu) not allocated in expected location (%llu)\n"),
> + progname,
> + (unsigned long long)mp->m_sb.sb_rootino,
> + (unsigned long long)ino);
> + exit(1);
> + }
> +}
> +
> int
> main(
> int argc,
> @@ -3835,12 +3867,7 @@ main(
> /*
> * Protect ourselves against possible stupidity
> */
> - if (XFS_INO_TO_AGNO(mp, mp->m_sb.sb_rootino) != 0) {
> - fprintf(stderr,
> - _("%s: root inode created in AG %u, not AG 0\n"),
> - progname, XFS_INO_TO_AGNO(mp, mp->m_sb.sb_rootino));
> - exit(1);
> - }
> + check_root_ino(mp);
>
> /*
> * Re-write multiple secondary superblocks with rootinode field set
>
