xfs: create inode pointer verifiers

Create some helper functions to check that inode pointers point to
somewhere within the filesystem and not at the static AG metadata.
Move xfs_internal_inum and create a directory inode check function.
We will use these functions in scrub and elsewhere.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
This commit is contained in:
Darrick J. Wong 2017-10-17 21:37:34 -07:00
parent 52c732eee7
commit 91fb9afc08
5 changed files with 99 additions and 27 deletions

View file

@ -2664,3 +2664,93 @@ xfs_ialloc_pagi_init(
xfs_trans_brelse(tp, bp);
return 0;
}
/* Calculate the first and last possible inode number in an AG. */
void
xfs_ialloc_agino_range(
struct xfs_mount *mp,
xfs_agnumber_t agno,
xfs_agino_t *first,
xfs_agino_t *last)
{
xfs_agblock_t bno;
xfs_agblock_t eoag;
eoag = xfs_ag_block_count(mp, agno);
/*
* Calculate the first inode, which will be in the first
* cluster-aligned block after the AGFL.
*/
bno = round_up(XFS_AGFL_BLOCK(mp) + 1,
xfs_ialloc_cluster_alignment(mp));
*first = XFS_OFFBNO_TO_AGINO(mp, bno, 0);
/*
* Calculate the last inode, which will be at the end of the
* last (aligned) cluster that can be allocated in the AG.
*/
bno = round_down(eoag, xfs_ialloc_cluster_alignment(mp));
*last = XFS_OFFBNO_TO_AGINO(mp, bno, 0) - 1;
}
/*
* Verify that an AG inode number pointer neither points outside the AG
* nor points at static metadata.
*/
bool
xfs_verify_agino(
struct xfs_mount *mp,
xfs_agnumber_t agno,
xfs_agino_t agino)
{
xfs_agino_t first;
xfs_agino_t last;
xfs_ialloc_agino_range(mp, agno, &first, &last);
return agino >= first && agino <= last;
}
/*
* Verify that an FS inode number pointer neither points outside the
* filesystem nor points at static AG metadata.
*/
bool
xfs_verify_ino(
struct xfs_mount *mp,
xfs_ino_t ino)
{
xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ino);
xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ino);
if (agno >= mp->m_sb.sb_agcount)
return false;
if (XFS_AGINO_TO_INO(mp, agno, agino) != ino)
return false;
return xfs_verify_agino(mp, agno, agino);
}
/* Is this an internal inode number? */
bool
xfs_internal_inum(
struct xfs_mount *mp,
xfs_ino_t ino)
{
return ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
(xfs_sb_version_hasquota(&mp->m_sb) &&
xfs_is_quota_inode(&mp->m_sb, ino));
}
/*
* Verify that a directory entry's inode number doesn't point at an internal
* inode, empty space, or static AG metadata.
*/
bool
xfs_verify_dir_ino(
struct xfs_mount *mp,
xfs_ino_t ino)
{
if (xfs_internal_inum(mp, ino))
return false;
return xfs_verify_ino(mp, ino);
}