Re: [PATCH 2/9] xfs: report ag header corruption errors to the health tracking system

Brian Foster
2019-11-20T14:20:53Z

On Thu, Nov 14, 2019 at 10:19:26AM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
>
> Whenever we encounter a corrupt AG header, we should report that to the
> health monitoring system for later reporting.
>
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---
> fs/xfs/libxfs/xfs_alloc.c | 6 ++++++
> fs/xfs/libxfs/xfs_health.h | 6 ++++++
> fs/xfs/libxfs/xfs_ialloc.c | 3 +++
> fs/xfs/libxfs/xfs_refcount.c | 5 ++++-
> fs/xfs/libxfs/xfs_rmap.c | 5 ++++-
> fs/xfs/libxfs/xfs_sb.c | 2 ++
> fs/xfs/xfs_health.c | 17 +++++++++++++++++
> fs/xfs/xfs_inode.c | 9 +++++++++
> 8 files changed, 51 insertions(+), 2 deletions(-)
>
>
> diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
> index c284e10af491..e75e3ae6c912 100644
> --- a/fs/xfs/libxfs/xfs_alloc.c
> +++ b/fs/xfs/libxfs/xfs_alloc.c
> @@ -26,6 +26,7 @@
> #include "xfs_log.h"
> #include "xfs_ag_resv.h"
> #include "xfs_bmap.h"
> +#include "xfs_health.h"
>
> extern kmem_zone_t *xfs_bmap_free_item_zone;
>
> @@ -699,6 +700,8 @@ xfs_alloc_read_agfl(
> mp, tp, mp->m_ddev_targp,
> XFS_AG_DADDR(mp, agno, XFS_AGFL_DADDR(mp)),
> XFS_FSS_TO_BB(mp, 1), 0, &bp, &xfs_agfl_buf_ops);
> + if (xfs_metadata_is_sick(error))
> + xfs_agno_mark_sick(mp, agno, XFS_SICK_AG_AGFL);

Any reason we couldn't do some of these in verifiers? I'm assuming we'd
still need calls in various external corruption checks, but at least we
wouldn't add a requirement to check all future buffer reads, etc.

> if (error)
> return error;
> xfs_buf_set_ref(bp, XFS_AGFL_REF);
> @@ -722,6 +725,7 @@ xfs_alloc_update_counters(
> if (unlikely(be32_to_cpu(agf->agf_freeblks) >
> be32_to_cpu(agf->agf_length))) {
> xfs_buf_corruption_error(agbp);
> + xfs_ag_mark_sick(pag, XFS_SICK_AG_AGF);
> return -EFSCORRUPTED;
> }
>
> @@ -2952,6 +2956,8 @@ xfs_read_agf(
> mp, tp, mp->m_ddev_targp,
> XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
> XFS_FSS_TO_BB(mp, 1), flags, bpp, &xfs_agf_buf_ops);
> + if (xfs_metadata_is_sick(error))
> + xfs_agno_mark_sick(mp, agno, XFS_SICK_AG_AGF);
> if (error)
> return error;
> if (!*bpp)
> diff --git a/fs/xfs/libxfs/xfs_health.h b/fs/xfs/libxfs/xfs_health.h
> index 3657a9cb8490..ce8954a10c66 100644
> --- a/fs/xfs/libxfs/xfs_health.h
> +++ b/fs/xfs/libxfs/xfs_health.h
> @@ -123,6 +123,8 @@ void xfs_rt_mark_healthy(struct xfs_mount *mp, unsigned int mask);
> void xfs_rt_measure_sickness(struct xfs_mount *mp, unsigned int *sick,
> unsigned int *checked);
>
> +void xfs_agno_mark_sick(struct xfs_mount *mp, xfs_agnumber_t agno,
> + unsigned int mask);
> void xfs_ag_mark_sick(struct xfs_perag *pag, unsigned int mask);
> void xfs_ag_mark_checked(struct xfs_perag *pag, unsigned int mask);
> void xfs_ag_mark_healthy(struct xfs_perag *pag, unsigned int mask);
> @@ -203,4 +205,8 @@ void xfs_fsop_geom_health(struct xfs_mount *mp, struct xfs_fsop_geom *geo);
> void xfs_ag_geom_health(struct xfs_perag *pag, struct xfs_ag_geometry *ageo);
> void xfs_bulkstat_health(struct xfs_inode *ip, struct xfs_bulkstat *bs);
>
> +#define xfs_metadata_is_sick(error) \
> + (unlikely((error) == -EFSCORRUPTED || (error) == -EIO || \
> + (error) == -EFSBADCRC))

Why is -EIO considered sick? My understanding is that once something is
marked sick, scrub is the only way to clear that state. -EIO can be
transient, so afaict that means we could mark a persistent in-core state
based on a transient/resolved issue.

Along similar lines, what's the expected behavior in the event of any of
these errors for a kernel that might not support
CONFIG_XFS_ONLINE_[SCRUB|REPAIR]? Just set the states that are never
used for anything? If so, that seems Ok I suppose.. but it's a little
awkward if we'd see the tracepoints and such associated with the state
changes.

Brian

> +
> #endif /* __XFS_HEALTH_H__ */
> diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
> index 988cde7744e6..c401512a4350 100644
> --- a/fs/xfs/libxfs/xfs_ialloc.c
> +++ b/fs/xfs/libxfs/xfs_ialloc.c
> @@ -27,6 +27,7 @@
> #include "xfs_trace.h"
> #include "xfs_log.h"
> #include "xfs_rmap.h"
> +#include "xfs_health.h"
>
> /*
> * Lookup a record by ino in the btree given by cur.
> @@ -2635,6 +2636,8 @@ xfs_read_agi(
> error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
> XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
> XFS_FSS_TO_BB(mp, 1), 0, bpp, &xfs_agi_buf_ops);
> + if (xfs_metadata_is_sick(error))
> + xfs_agno_mark_sick(mp, agno, XFS_SICK_AG_AGI);
> if (error)
> return error;
> if (tp)
> diff --git a/fs/xfs/libxfs/xfs_refcount.c b/fs/xfs/libxfs/xfs_refcount.c
> index d7d702ee4d1a..25c87834e42a 100644
> --- a/fs/xfs/libxfs/xfs_refcount.c
> +++ b/fs/xfs/libxfs/xfs_refcount.c
> @@ -22,6 +22,7 @@
> #include "xfs_bit.h"
> #include "xfs_refcount.h"
> #include "xfs_rmap.h"
> +#include "xfs_health.h"
>
> /* Allowable refcount adjustment amounts. */
> enum xfs_refc_adjust_op {
> @@ -1177,8 +1178,10 @@ xfs_refcount_finish_one(
> XFS_ALLOC_FLAG_FREEING, &agbp);
> if (error)
> return error;
> - if (XFS_IS_CORRUPT(tp->t_mountp, !agbp))
> + if (XFS_IS_CORRUPT(tp->t_mountp, !agbp)) {
> + xfs_agno_mark_sick(tp->t_mountp, agno, XFS_SICK_AG_AGF);
> return -EFSCORRUPTED;
> + }
>
> rcur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno);
> if (!rcur) {
> diff --git a/fs/xfs/libxfs/xfs_rmap.c b/fs/xfs/libxfs/xfs_rmap.c
> index ff9412f113c4..a54a3c129cce 100644
> --- a/fs/xfs/libxfs/xfs_rmap.c
> +++ b/fs/xfs/libxfs/xfs_rmap.c
> @@ -21,6 +21,7 @@
> #include "xfs_errortag.h"
> #include "xfs_error.h"
> #include "xfs_inode.h"
> +#include "xfs_health.h"
>
> /*
> * Lookup the first record less than or equal to [bno, len, owner, offset]
> @@ -2400,8 +2401,10 @@ xfs_rmap_finish_one(
> error = xfs_free_extent_fix_freelist(tp, agno, &agbp);
> if (error)
> return error;
> - if (XFS_IS_CORRUPT(tp->t_mountp, !agbp))
> + if (XFS_IS_CORRUPT(tp->t_mountp, !agbp)) {
> + xfs_agno_mark_sick(tp->t_mountp, agno, XFS_SICK_AG_AGF);
> return -EFSCORRUPTED;
> + }
>
> rcur = xfs_rmapbt_init_cursor(mp, tp, agbp, agno);
> if (!rcur) {
> diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
> index 0ac69751fe85..4a923545465d 100644
> --- a/fs/xfs/libxfs/xfs_sb.c
> +++ b/fs/xfs/libxfs/xfs_sb.c
> @@ -1169,6 +1169,8 @@ xfs_sb_read_secondary(
> error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
> XFS_AG_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
> XFS_FSS_TO_BB(mp, 1), 0, &bp, &xfs_sb_buf_ops);
> + if (xfs_metadata_is_sick(error))
> + xfs_agno_mark_sick(mp, agno, XFS_SICK_AG_SB);
> if (error)
> return error;
> xfs_buf_set_ref(bp, XFS_SSB_REF);
> diff --git a/fs/xfs/xfs_health.c b/fs/xfs/xfs_health.c
> index 860dc70c99e7..36c32b108b39 100644
> --- a/fs/xfs/xfs_health.c
> +++ b/fs/xfs/xfs_health.c
> @@ -200,6 +200,23 @@ xfs_rt_measure_sickness(
> spin_unlock(&mp->m_sb_lock);
> }
>
> +/* Mark unhealthy per-ag metadata given a raw AG number. */
> +void
> +xfs_agno_mark_sick(
> + struct xfs_mount *mp,
> + xfs_agnumber_t agno,
> + unsigned int mask)
> +{
> + struct xfs_perag *pag = xfs_perag_get(mp, agno);
> +
> + /* per-ag structure not set up yet? */
> + if (!pag)
> + return;
> +
> + xfs_ag_mark_sick(pag, mask);
> + xfs_perag_put(pag);
> +}
> +
> /* Mark unhealthy per-ag metadata. */
> void
> xfs_ag_mark_sick(
> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
> index 401da197f012..a2812cea748d 100644
> --- a/fs/xfs/xfs_inode.c
> +++ b/fs/xfs/xfs_inode.c
> @@ -35,6 +35,7 @@
> #include "xfs_log.h"
> #include "xfs_bmap_btree.h"
> #include "xfs_reflink.h"
> +#include "xfs_health.h"
>
> kmem_zone_t *xfs_inode_zone;
>
> @@ -787,6 +788,8 @@ xfs_ialloc(
> */
> if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
> xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
> + xfs_agno_mark_sick(mp, XFS_INO_TO_AGNO(mp, ino),
> + XFS_SICK_AG_INOBT);
> return -EFSCORRUPTED;
> }
>
> @@ -2137,6 +2140,7 @@ xfs_iunlink_update_bucket(
> */
> if (old_value == new_agino) {
> xfs_buf_corruption_error(agibp);
> + xfs_agno_mark_sick(tp->t_mountp, agno, XFS_SICK_AG_AGI);
> return -EFSCORRUPTED;
> }
>
> @@ -2203,6 +2207,7 @@ xfs_iunlink_update_inode(
> if (!xfs_verify_agino_or_null(mp, agno, old_value)) {
> xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
> sizeof(*dip), __this_address);
> + xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
> error = -EFSCORRUPTED;
> goto out;
> }
> @@ -2217,6 +2222,7 @@ xfs_iunlink_update_inode(
> if (next_agino != NULLAGINO) {
> xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
> dip, sizeof(*dip), __this_address);
> + xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
> error = -EFSCORRUPTED;
> }
> goto out;
> @@ -2271,6 +2277,7 @@ xfs_iunlink(
> if (next_agino == agino ||
> !xfs_verify_agino_or_null(mp, agno, next_agino)) {
> xfs_buf_corruption_error(agibp);
> + xfs_agno_mark_sick(mp, agno, XFS_SICK_AG_AGI);
> return -EFSCORRUPTED;
> }
>
> @@ -2408,6 +2415,7 @@ xfs_iunlink_map_prev(
> XFS_CORRUPTION_ERROR(__func__,
> XFS_ERRLEVEL_LOW, mp,
> *dipp, sizeof(**dipp));
> + xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
> error = -EFSCORRUPTED;
> return error;
> }
> @@ -2454,6 +2462,7 @@ xfs_iunlink_remove(
> if (!xfs_verify_agino(mp, agno, head_agino)) {
> XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
> agi, sizeof(*agi));
> + xfs_agno_mark_sick(mp, agno, XFS_SICK_AG_AGI);
> return -EFSCORRUPTED;
> }
>
>