On Tue, May 19, 2020 at 06:51:02PM -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>
> ---
> repair/phase5.c | 239 ++++++++++++++++++++++++++++++++++++++++++++++++++-----
> 1 file changed, 218 insertions(+), 21 deletions(-)
>
>
> diff --git a/repair/phase5.c b/repair/phase5.c
> index 84c05a13..8f5e5f59 100644
> --- a/repair/phase5.c
> +++ b/repair/phase5.c
> @@ -18,6 +18,7 @@
> #include "progress.h"
> #include "slab.h"
> #include "rmap.h"
> +#include "bload.h"
>
> /*
> * we maintain the current slice (path from root to leaf)
...
> @@ -306,6 +324,156 @@ _("error - not enough free space in filesystem\n"));
> #endif
> }
>
...
> +static void
> +consume_freespace(
> + xfs_agnumber_t agno,
> + struct extent_tree_node *ext_ptr,
> + uint32_t len)
> +{
> + struct extent_tree_node *bno_ext_ptr;
> + xfs_agblock_t new_start = ext_ptr->ex_startblock + len;
> + xfs_extlen_t 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);
> + release_extent_tree_node(ext_ptr);
> +
Not having looked too deeply at the in-core extent tracking structures,
is there any particular reason we unconditionally remove and reinsert
new records each time around? Is it because we're basically changing the
extent index in the tree? If so, comment please (an update to the
comment below is probably fine). :)
> + /*
> + * If we only used part of this last extent, then we must reinsert the
> + * extent in the extent trees.
> + */
> + if (new_len > 0) {
> + add_bno_extent(agno, new_start, new_len);
> + add_bcnt_extent(agno, new_start, new_len);
> + }
> +}
> +
> +/* 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;
> + uint32_t blocks_allocated = 0;
> + uint32_t len;
> + int error;
> +
> + while (blocks_allocated < nr_blocks) {
> + /*
> + * 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);
Extra whitespace ^
> + 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, nr_blocks - blocks_allocated);
> + error = xrep_newbt_add_blocks(&btr->newbt,
> + XFS_AGB_TO_FSB(mp, agno,
> + ext_ptr->ex_startblock),
> + len);
Alignment.
> + if (error)
> + do_error(_("could not set up btree reservation: %s\n"),
> + strerror(-error));
> +
> + 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));
> +
> + consume_freespace(agno, ext_ptr, len);
> + blocks_allocated += len;
> + }
> +#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_claim_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);
> +}
> +
Seems like an unnecessary helper, unless this grows more code in later
patches..?
> static void
> write_cursor(bt_status_t *curs)
> {
...
> @@ -2287,28 +2483,29 @@ 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, };
I don't see any reason to add sc here when it's still unused. It's not
as if a single variable is saving complexity somewhere else. I guess
I'll defer to Eric on the approach wrt to the other unused warnings.
Also, what's the purpose of the rmap change below? I'm wondering if that
(along with all of the indentation cleanup) should be its own patch with
appropriate explanation.
Brian
> + 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);
> @@ -2516,8 +2713,8 @@ 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;
>
>
