On Sat, Aug 11, 2018 at 08:35:15AM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
>
> Check the values we read in from the AG headers when calculating the
> block reservations for a repair transaction. If they're obviously
> wrong, substitute worst case assumptions (rather than ENOSPC on a bogus
> reservatoin request).
reservation ^
Other than that:
Reviewed-by: Carlos Maiolino <cmaiolino@xxxxxxxxxx>
>
> Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> ---
> fs/xfs/scrub/repair.c | 46 +++++++++++++++++++++++++++-------------------
> 1 file changed, 27 insertions(+), 19 deletions(-)
>
>
> diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
> index 42d8c798ce7d..97c3077fb005 100644
> --- a/fs/xfs/scrub/repair.c
> +++ b/fs/xfs/scrub/repair.c
> @@ -195,8 +195,8 @@ xrep_calc_ag_resblks(
> struct xfs_scrub_metadata *sm = sc->sm;
> struct xfs_perag *pag;
> struct xfs_buf *bp;
> - xfs_agino_t icount = 0;
> - xfs_extlen_t aglen = 0;
> + xfs_agino_t icount = NULLAGINO;
> + xfs_extlen_t aglen = NULLAGBLOCK;
> xfs_extlen_t usedlen;
> xfs_extlen_t freelen;
> xfs_extlen_t bnobt_sz;
> @@ -208,20 +208,14 @@ xrep_calc_ag_resblks(
> if (!(sm->sm_flags & XFS_SCRUB_IFLAG_REPAIR))
> return 0;
>
> - /* Use in-core counters if possible. */
> pag = xfs_perag_get(mp, sm->sm_agno);
> - if (pag->pagi_init)
> + if (pag->pagi_init) {
> + /* Use in-core icount if possible. */
> icount = pag->pagi_count;
> -
> - /*
> - * Otherwise try to get the actual counters from disk; if not, make
> - * some worst case assumptions.
> - */
> - if (icount == 0) {
> + } else {
> + /* Try to get the actual counters from disk. */
> error = xfs_ialloc_read_agi(mp, NULL, sm->sm_agno, &bp);
> - if (error) {
> - icount = mp->m_sb.sb_agblocks / mp->m_sb.sb_inopblock;
> - } else {
> + if (!error) {
> icount = pag->pagi_count;
> xfs_buf_relse(bp);
> }
> @@ -229,18 +223,32 @@ xrep_calc_ag_resblks(
>
> /* Now grab the block counters from the AGF. */
> error = xfs_alloc_read_agf(mp, NULL, sm->sm_agno, 0, &bp);
> - if (error) {
> - aglen = mp->m_sb.sb_agblocks;
> - freelen = aglen;
> - usedlen = aglen;
> - } else {
> + if (!error) {
> aglen = be32_to_cpu(XFS_BUF_TO_AGF(bp)->agf_length);
> - freelen = pag->pagf_freeblks;
> + freelen = be32_to_cpu(XFS_BUF_TO_AGF(bp)->agf_freeblks);
> usedlen = aglen - freelen;
> xfs_buf_relse(bp);
> }
> xfs_perag_put(pag);
>
> + /* If the icount is impossible, make some worst-case assumptions. */
> + if (icount == NULLAGINO ||
> + !xfs_verify_agino(mp, sm->sm_agno, icount)) {
> + xfs_agino_t first, last;
> +
> + xfs_agino_range(mp, sm->sm_agno, &first, &last);
> + icount = last - first + 1;
> + }
> +
> + /* If the block counts are impossible, make worst-case assumptions. */
> + if (aglen == NULLAGBLOCK ||
> + aglen != xfs_ag_block_count(mp, sm->sm_agno) ||
> + freelen >= aglen) {
> + aglen = xfs_ag_block_count(mp, sm->sm_agno);
> + freelen = aglen;
> + usedlen = aglen;
> + }
> +
> trace_xrep_calc_ag_resblks(mp, sm->sm_agno, icount, aglen,
> freelen, usedlen);
>
>
--
Carlos
