Re: [PATCH 2/8] xfs: don't continue scrub if already corrupt

Brian Foster
2018-05-11T15:19:26Z

On Thu, May 10, 2018 at 12:18:13PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
>
> If we've already decided that something is corrupt, we might as well
> abort all the loops and exit as quickly as possible.
>
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---

Reviewed-by: Brian Foster <bfoster@redhat.com>

> fs/xfs/scrub/attr.c | 3 ++-
> fs/xfs/scrub/bmap.c | 3 ++-
> fs/xfs/scrub/dir.c | 35 +++++++++++++++++++++++++++--------
> fs/xfs/scrub/parent.c | 3 +++
> 4 files changed, 34 insertions(+), 10 deletions(-)
>
>
> diff --git a/fs/xfs/scrub/attr.c b/fs/xfs/scrub/attr.c
> index 127575f0abfb..84b6d6b66578 100644
> --- a/fs/xfs/scrub/attr.c
> +++ b/fs/xfs/scrub/attr.c
> @@ -126,8 +126,9 @@ xfs_scrub_xattr_listent(
> if (args.valuelen != valuelen)
> xfs_scrub_fblock_set_corrupt(sx->sc, XFS_ATTR_FORK,
> args.blkno);
> -
> fail_xref:
> + if (sx->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + context->seen_enough = 1;
> return;
> }
>
> diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
> index e5a4611abf86..42a115e83739 100644
> --- a/fs/xfs/scrub/bmap.c
> +++ b/fs/xfs/scrub/bmap.c
> @@ -683,7 +683,8 @@ xfs_scrub_bmap(
> info.lastoff = 0;
> ifp = XFS_IFORK_PTR(ip, whichfork);
> for_each_xfs_iext(ifp, &icur, &irec) {
> - if (xfs_scrub_should_terminate(sc, &error))
> + if (xfs_scrub_should_terminate(sc, &error) ||
> + (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT))
> break;
> if (isnullstartblock(irec.br_startblock))
> continue;
> diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c
> index 38f29806eb54..1a4309b3e786 100644
> --- a/fs/xfs/scrub/dir.c
> +++ b/fs/xfs/scrub/dir.c
> @@ -172,7 +172,7 @@ xfs_scrub_dir_actor(
> error = xfs_dir_lookup(sdc->sc->tp, ip, &xname, &lookup_ino, NULL);
> if (!xfs_scrub_fblock_process_error(sdc->sc, XFS_DATA_FORK, offset,
> &error))
> - goto fail_xref;
> + goto out;
> if (lookup_ino != ino) {
> xfs_scrub_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset);
> goto out;
> @@ -183,8 +183,13 @@ xfs_scrub_dir_actor(
> if (error)
> goto out;
> out:
> - return error;
> -fail_xref:
> + /*
> + * A negative error code returned here is supposed to cause the
> + * dir_emit caller (xfs_readdir) to abort the directory iteration
> + * and return zero to xfs_scrub_directory.
> + */
> + if (error == 0 && sdc->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + return -EFSCORRUPTED;
> return error;
> }
>
> @@ -240,6 +245,9 @@ xfs_scrub_dir_rec(
> }
> xfs_scrub_buffer_recheck(ds->sc, bp);
>
> + if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + goto out_relse;
> +
> dent = (struct xfs_dir2_data_entry *)(((char *)bp->b_addr) + off);
>
> /* Make sure we got a real directory entry. */
> @@ -357,6 +365,9 @@ xfs_scrub_directory_data_bestfree(
>
> /* XXX: Check xfs_dir3_data_hdr.pad is zero once we start setting it. */
>
> + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + goto out_buf;
> +
> /* Do the bestfrees correspond to actual free space? */
> bf = d_ops->data_bestfree_p(bp->b_addr);
> smallest_bestfree = UINT_MAX;
> @@ -413,14 +424,18 @@ xfs_scrub_directory_data_bestfree(
>
> /* Spot check this free entry */
> tag = be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup));
> - if (tag != ((char *)dup - (char *)bp->b_addr))
> + if (tag != ((char *)dup - (char *)bp->b_addr)) {
> xfs_scrub_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
> + goto out_buf;
> + }
>
> /*
> * Either this entry is a bestfree or it's smaller than
> * any of the bestfrees.
> */
> xfs_scrub_directory_check_free_entry(sc, lblk, bf, dup);
> + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + goto out_buf;
>
> /* Move on. */
> newlen = be16_to_cpu(dup->length);
> @@ -546,6 +561,8 @@ xfs_scrub_directory_leaf1_bestfree(
> }
> if (leafhdr.stale != stale)
> xfs_scrub_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
> + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + goto out;
>
> /* Check all the bestfree entries. */
> for (i = 0; i < bestcount; i++, bestp++) {
> @@ -556,9 +573,11 @@ xfs_scrub_directory_leaf1_bestfree(
> i * args->geo->fsbcount, -1, &dbp);
> if (!xfs_scrub_fblock_process_error(sc, XFS_DATA_FORK, lblk,
> &error))
> - continue;
> + break;
> xfs_scrub_directory_check_freesp(sc, lblk, dbp, best);
> xfs_trans_brelse(sc->tp, dbp);
> + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + goto out;
> }
> out:
> return error;
> @@ -607,7 +626,7 @@ xfs_scrub_directory_free_bestfree(
> -1, &dbp);
> if (!xfs_scrub_fblock_process_error(sc, XFS_DATA_FORK, lblk,
> &error))
> - continue;
> + break;
> xfs_scrub_directory_check_freesp(sc, lblk, dbp, best);
> xfs_trans_brelse(sc->tp, dbp);
> }
> @@ -656,7 +675,7 @@ xfs_scrub_directory_blocks(
>
> /* Iterate all the data extents in the directory... */
> found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
> - while (found) {
> + while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
> /* Block directories only have a single block at offset 0. */
> if (is_block &&
> (got.br_startoff > 0 ||
> @@ -719,7 +738,7 @@ xfs_scrub_directory_blocks(
> /* Scan for free blocks */
> lblk = free_lblk;
> found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
> - while (found) {
> + while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
> /*
> * Dirs can't have blocks mapped above 2^32.
> * Single-block dirs shouldn't even be here.
> diff --git a/fs/xfs/scrub/parent.c b/fs/xfs/scrub/parent.c
> index 1fb88c18d455..fc336807e156 100644
> --- a/fs/xfs/scrub/parent.c
> +++ b/fs/xfs/scrub/parent.c
> @@ -147,6 +147,9 @@ xfs_scrub_parent_validate(
>
> *try_again = false;
>
> + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
> + goto out;
> +
> /* '..' must not point to ourselves. */
> if (sc->ip->i_ino == dnum) {
> xfs_scrub_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);