On Thu, May 14, 2020 at 11:11:07AM -0400, Brian Foster wrote:
> On Sat, May 09, 2020 at 09:31:59AM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> >
> > Create some new support structures and functions to assist phase5 in
> > using the btree bulk loader to reconstruct metadata btrees. This is the
> > first step in removing the open-coded rebuilding code.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> > ---
>
> FYI, unused variable warnings:
>
> phase5.c: In function ‘phase5_func’:
> phase5.c:2491:20: warning: unused variable ‘sc’ [-Wunused-variable]
> 2491 | struct repair_ctx sc = { .mp = mp, };
> | ^~
> At top level:
> phase5.c:509:1: warning: ‘finish_rebuild’ defined but not used [-Wunused-function]
> 509 | finish_rebuild(
> | ^~~~~~~~~~~~~~
> phase5.c:468:1: warning: ‘rebuild_alloc_block’ defined but not used [-Wunused-function]
> 468 | rebuild_alloc_block(
> | ^~~~~~~~~~~~~~~~~~~
> phase5.c:381:1: warning: ‘setup_rebuild’ defined but not used [-Wunused-function]
> 381 | setup_rebuild(
> | ^~~~~~~~~~~~~
> phase5.c:366:1: warning: ‘init_rebuild’ defined but not used [-Wunused-function]
> 366 | init_rebuild(
> | ^~~~~~~~~~~~
Yeah... these aren't used by anything until the next patch, and I was
trying to keep the "infrastructure you need for X" changes separate from
"X". Though every time I do that, people complain about me adding code
that isn't used anywhere...
> > repair/phase5.c | 240 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
> > 1 file changed, 219 insertions(+), 21 deletions(-)
> >
> >
> > diff --git a/repair/phase5.c b/repair/phase5.c
> > index f3be15de..7eb24519 100644
> > --- a/repair/phase5.c
> > +++ b/repair/phase5.c
> ...
> > @@ -306,6 +324,157 @@ _("error - not enough free space in filesystem\n"));
> ...
> > +/* Reserve blocks for the new btree. */
> > +static void
> > +setup_rebuild(
> > + struct xfs_mount *mp,
> > + xfs_agnumber_t agno,
> > + struct bt_rebuild *btr,
> > + uint32_t nr_blocks)
> > +{
> > + struct extent_tree_node *ext_ptr;
> > + struct extent_tree_node *bno_ext_ptr;
> > + uint32_t blocks_allocated = 0;
> > + int error;
> > +
> > + /*
> > + * grab the smallest extent and use it up, then get the
> > + * next smallest. This mimics the init_*_cursor code.
> > + */
> > + ext_ptr = findfirst_bcnt_extent(agno);
> > +
> > + /*
> > + * set up the free block array
> > + */
> > + while (blocks_allocated < nr_blocks) {
> > + uint64_t len;
> > + xfs_agblock_t new_start;
> > + xfs_extlen_t new_len;
> > +
> > + if (!ext_ptr)
> > + do_error(
> > +_("error - not enough free space in filesystem\n"));
> > +
> > + /* Use up the extent we've got. */
> > + len = min(ext_ptr->ex_blockcount,
> > + btr->bload.nr_blocks - blocks_allocated);
>
> What's the difference between the nr_blocks parameter and this one?
I think that's a bug, and should have been:
len = min(ext_ptr->ex_blockcount, nr_blocks - blocks_allocated);
> > + error = xrep_newbt_add_reservation(&btr->newbt,
> > + XFS_AGB_TO_FSB(mp, agno,
> > + ext_ptr->ex_startblock),
> > + len, NULL);
> > + if (error)
> > + do_error(_("could not set up btree reservation: %s\n"),
> > + strerror(-error));
> > + blocks_allocated += len;
> > +
> > + error = rmap_add_ag_rec(mp, agno, ext_ptr->ex_startblock, len,
> > + btr->newbt.oinfo.oi_owner);
> > + if (error)
> > + do_error(_("could not set up btree rmaps: %s\n"),
> > + strerror(-error));
> > +
> > + /* Figure out if we're putting anything back. */
>
> The remaining extent replacement bits of this loop looks like it could
> warrant a little helper and a comment to explain exactly what's
> happening at a high level.
Ok, I'll figure something out.
--D
> Brian
>
> > + new_start = ext_ptr->ex_startblock + len;
> > + new_len = ext_ptr->ex_blockcount - len;
> > +
> > + /* Delete the used-up extent from both extent trees. */
> > +#ifdef XR_BLD_FREE_TRACE
> > + fprintf(stderr, "releasing extent: %u [%u %u]\n",
> > + agno, ext_ptr->ex_startblock, ext_ptr->ex_blockcount);
> > +#endif
> > + bno_ext_ptr = find_bno_extent(agno, ext_ptr->ex_startblock);
> > + ASSERT(bno_ext_ptr != NULL);
> > + get_bno_extent(agno, bno_ext_ptr);
> > + release_extent_tree_node(bno_ext_ptr);
> > +
> > + ext_ptr = get_bcnt_extent(agno, ext_ptr->ex_startblock,
> > + ext_ptr->ex_blockcount);
> > + ASSERT(ext_ptr != NULL);
> > + release_extent_tree_node(ext_ptr);
> > +
> > + /*
> > + * If we only used part of this last extent, then we need only
> > + * to reinsert the extent in the extent trees and we're done.
> > + */
> > + if (new_len > 0) {
> > + add_bno_extent(agno, new_start, new_len);
> > + add_bcnt_extent(agno, new_start, new_len);
> > + break;
> > + }
> > +
> > + /* Otherwise, find the next biggest extent. */
> > + ext_ptr = findfirst_bcnt_extent(agno);
> > + }
> > +#ifdef XR_BLD_FREE_TRACE
> > + fprintf(stderr, "blocks_allocated = %d\n",
> > + blocks_allocated);
> > +#endif
> > +}
> > +
> > +/* Feed one of the new btree blocks to the bulk loader. */
> > +static int
> > +rebuild_alloc_block(
> > + struct xfs_btree_cur *cur,
> > + union xfs_btree_ptr *ptr,
> > + void *priv)
> > +{
> > + struct bt_rebuild *btr = priv;
> > +
> > + return xrep_newbt_claim_block(cur, &btr->newbt, ptr);
> > +}
> > +
> > static void
> > write_cursor(bt_status_t *curs)
> > {
> > @@ -336,6 +505,34 @@ finish_cursor(bt_status_t *curs)
> > free(curs->btree_blocks);
> > }
> >
> > +static void
> > +finish_rebuild(
> > + struct xfs_mount *mp,
> > + struct bt_rebuild *btr)
> > +{
> > + struct xrep_newbt_resv *resv, *n;
> > +
> > + for_each_xrep_newbt_reservation(&btr->newbt, resv, n) {
> > + xfs_agnumber_t agno;
> > + xfs_agblock_t bno;
> > + xfs_extlen_t len;
> > +
> > + if (resv->used >= resv->len)
> > + continue;
> > +
> > + /* XXX: Shouldn't this go on the AGFL? */
> > + /* Put back everything we didn't use. */
> > + bno = XFS_FSB_TO_AGBNO(mp, resv->fsbno + resv->used);
> > + agno = XFS_FSB_TO_AGNO(mp, resv->fsbno + resv->used);
> > + len = resv->len - resv->used;
> > +
> > + add_bno_extent(agno, bno, len);
> > + add_bcnt_extent(agno, bno, len);
> > + }
> > +
> > + xrep_newbt_destroy(&btr->newbt, 0);
> > +}
> > +
> > /*
> > * We need to leave some free records in the tree for the corner case of
> > * setting up the AGFL. This may require allocation of blocks, and as
> > @@ -2290,28 +2487,29 @@ keep_fsinos(xfs_mount_t *mp)
> >
> > static void
> > phase5_func(
> > - xfs_mount_t *mp,
> > - xfs_agnumber_t agno,
> > - struct xfs_slab *lost_fsb)
> > + struct xfs_mount *mp,
> > + xfs_agnumber_t agno,
> > + struct xfs_slab *lost_fsb)
> > {
> > - uint64_t num_inos;
> > - uint64_t num_free_inos;
> > - uint64_t finobt_num_inos;
> > - uint64_t finobt_num_free_inos;
> > - bt_status_t bno_btree_curs;
> > - bt_status_t bcnt_btree_curs;
> > - bt_status_t ino_btree_curs;
> > - bt_status_t fino_btree_curs;
> > - bt_status_t rmap_btree_curs;
> > - bt_status_t refcnt_btree_curs;
> > - int extra_blocks = 0;
> > - uint num_freeblocks;
> > - xfs_extlen_t freeblks1;
> > + struct repair_ctx sc = { .mp = mp, };
> > + struct agi_stat agi_stat = {0,};
> > + uint64_t num_inos;
> > + uint64_t num_free_inos;
> > + uint64_t finobt_num_inos;
> > + uint64_t finobt_num_free_inos;
> > + bt_status_t bno_btree_curs;
> > + bt_status_t bcnt_btree_curs;
> > + bt_status_t ino_btree_curs;
> > + bt_status_t fino_btree_curs;
> > + bt_status_t rmap_btree_curs;
> > + bt_status_t refcnt_btree_curs;
> > + int extra_blocks = 0;
> > + uint num_freeblocks;
> > + xfs_extlen_t freeblks1;
> > #ifdef DEBUG
> > - xfs_extlen_t freeblks2;
> > + xfs_extlen_t freeblks2;
> > #endif
> > - xfs_agblock_t num_extents;
> > - struct agi_stat agi_stat = {0,};
> > + xfs_agblock_t num_extents;
> >
> > if (verbose)
> > do_log(_(" - agno = %d\n"), agno);
> > @@ -2533,8 +2731,8 @@ inject_lost_blocks(
> > if (error)
> > goto out_cancel;
> >
> > - error = -libxfs_free_extent(tp, *fsb, 1, &XFS_RMAP_OINFO_AG,
> > - XFS_AG_RESV_NONE);
> > + error = -libxfs_free_extent(tp, *fsb, 1,
> > + &XFS_RMAP_OINFO_ANY_OWNER, XFS_AG_RESV_NONE);
> > if (error)
> > goto out_cancel;
> >
> >
>
