1 files changed, 260 insertions, 0 deletions

diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
index 588bc054db5c..beebd484c5f3 100644
--- a/fs/xfs/scrub/repair.c
+++ b/fs/xfs/scrub/repair.c
@@ -359,6 +359,266 @@ xrep_init_btblock(
 	return 0;
 }
 
+/* Initialize accounting resources for staging a new AG btree. */
+void
+xrep_newbt_init_ag(
+	struct xrep_newbt		*xnr,
+	struct xfs_scrub		*sc,
+	const struct xfs_owner_info	*oinfo,
+	xfs_fsblock_t			alloc_hint,
+	enum xfs_ag_resv_type		resv)
+{
+	memset(xnr, 0, sizeof(struct xrep_newbt));
+	xnr->sc = sc;
+	xnr->oinfo = *oinfo; /* structure copy */
+	xnr->alloc_hint = alloc_hint;
+	xnr->resv = resv;
+	INIT_LIST_HEAD(&xnr->reservations);
+}
+
+/* Initialize accounting resources for staging a new inode fork btree. */
+void
+xrep_newbt_init_inode(
+	struct xrep_newbt		*xnr,
+	struct xfs_scrub		*sc,
+	int				whichfork,
+	const struct xfs_owner_info	*oinfo)
+{
+	memset(xnr, 0, sizeof(struct xrep_newbt));
+	xnr->sc = sc;
+	xnr->oinfo = *oinfo; /* structure copy */
+	xnr->alloc_hint = XFS_INO_TO_FSB(sc->mp, sc->ip->i_ino);
+	xnr->resv = XFS_AG_RESV_NONE;
+	xnr->ifake.if_fork = kmem_zone_zalloc(xfs_ifork_zone, 0);
+	xnr->ifake.if_fork_size = XFS_IFORK_SIZE(sc->ip, whichfork);
+	INIT_LIST_HEAD(&xnr->reservations);
+}
+
+/*
+ * Initialize accounting resources for staging a new btree.  Callers are
+ * expected to add their own reservations (and clean them up) manually.
+ */
+void
+xrep_newbt_init_bare(
+	struct xrep_newbt		*xnr,
+	struct xfs_scrub		*sc)
+{
+	xrep_newbt_init_ag(xnr, sc, &XFS_RMAP_OINFO_ANY_OWNER, NULLFSBLOCK,
+			XFS_AG_RESV_NONE);
+}
+
+/* Add a space reservation manually. */
+int
+xrep_newbt_add_reservation(
+	struct xrep_newbt		*xnr,
+	xfs_fsblock_t			fsbno,
+	xfs_extlen_t			len)
+{
+	struct xrep_newbt_resv	*resv;
+
+	resv = kmem_alloc(sizeof(struct xrep_newbt_resv), KM_MAYFAIL);
+	if (!resv)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&resv->list);
+	resv->fsbno = fsbno;
+	resv->len = len;
+	resv->used = 0;
+	list_add_tail(&resv->list, &xnr->reservations);
+	return 0;
+}
+
+/* Reserve disk space for our new btree. */
+int
+xrep_newbt_reserve_space(
+	struct xrep_newbt	*xnr,
+	uint64_t		nr_blocks)
+{
+	struct xfs_scrub	*sc = xnr->sc;
+	xfs_alloctype_t		type;
+	xfs_fsblock_t		alloc_hint = xnr->alloc_hint;
+	int			error = 0;
+
+	type = sc->ip ? XFS_ALLOCTYPE_START_BNO : XFS_ALLOCTYPE_NEAR_BNO;
+
+	while (nr_blocks > 0 && !error) {
+		struct xfs_alloc_arg	args = {
+			.tp		= sc->tp,
+			.mp		= sc->mp,
+			.type		= type,
+			.fsbno		= alloc_hint,
+			.oinfo		= xnr->oinfo,
+			.minlen		= 1,
+			.maxlen		= nr_blocks,
+			.prod		= nr_blocks,
+			.resv		= xnr->resv,
+		};
+
+		error = xfs_alloc_vextent(&args);
+		if (error)
+			return error;
+		if (args.fsbno == NULLFSBLOCK)
+			return -ENOSPC;
+
+		trace_xrep_newbt_reserve_space(sc->mp,
+				XFS_FSB_TO_AGNO(sc->mp, args.fsbno),
+				XFS_FSB_TO_AGBNO(sc->mp, args.fsbno),
+				args.len, xnr->oinfo.oi_owner);
+
+		error = xrep_newbt_add_reservation(xnr, args.fsbno, args.len);
+		if (error)
+			break;
+
+		nr_blocks -= args.len;
+		alloc_hint = args.fsbno + args.len - 1;
+
+		if (sc->ip)
+			error = xfs_trans_roll_inode(&sc->tp, sc->ip);
+		else
+			error = xrep_roll_ag_trans(sc);
+	}
+
+	return error;
+}
+
+/* Free all the accounting info and disk space we reserved for a new btree. */
+void
+xrep_newbt_destroy(
+	struct xrep_newbt	*xnr,
+	int			error)
+{
+	struct xfs_scrub	*sc = xnr->sc;
+	struct xrep_newbt_resv	*resv, *n;
+
+	if (error)
+		goto junkit;
+
+	list_for_each_entry_safe(resv, n, &xnr->reservations, list) {
+		/* Free every block we didn't use. */
+		resv->fsbno += resv->used;
+		resv->len -= resv->used;
+		resv->used = 0;
+
+		if (resv->len > 0) {
+			trace_xrep_newbt_unreserve_space(sc->mp,
+					XFS_FSB_TO_AGNO(sc->mp, resv->fsbno),
+					XFS_FSB_TO_AGBNO(sc->mp, resv->fsbno),
+					resv->len, xnr->oinfo.oi_owner);
+
+			__xfs_bmap_add_free(sc->tp, resv->fsbno, resv->len,
+					&xnr->oinfo, true);
+		}
+
+		list_del(&resv->list);
+		kmem_free(resv);
+	}
+
+junkit:
+	list_for_each_entry_safe(resv, n, &xnr->reservations, list) {
+		list_del(&resv->list);
+		kmem_free(resv);
+	}
+
+	if (sc->ip) {
+		kmem_zone_free(xfs_ifork_zone, xnr->ifake.if_fork);
+		xnr->ifake.if_fork = NULL;
+	}
+}
+
+/* Feed one of the reserved btree blocks to the bulk loader. */
+int
+xrep_newbt_alloc_block(
+	struct xfs_btree_cur	*cur,
+	struct xrep_newbt	*xnr,
+	union xfs_btree_ptr	*ptr)
+{
+	struct xrep_newbt_resv	*resv;
+	xfs_fsblock_t		fsb;
+
+	/*
+	 * If last_resv doesn't have a block for us, move forward until we find
+	 * one that does (or run out of reservations).
+	 */
+	if (xnr->last_resv == NULL) {
+		list_for_each_entry(resv, &xnr->reservations, list) {
+			if (resv->used < resv->len) {
+				xnr->last_resv = resv;
+				break;
+			}
+		}
+		if (xnr->last_resv == NULL)
+			return -ENOSPC;
+	} else if (xnr->last_resv->used == xnr->last_resv->len) {
+		if (xnr->last_resv->list.next == &xnr->reservations)
+			return -ENOSPC;
+		xnr->last_resv = list_entry(xnr->last_resv->list.next,
+				struct xrep_newbt_resv, list);
+	}
+
+	/* Nab the block. */
+	fsb = xnr->last_resv->fsbno + xnr->last_resv->used;
+	xnr->last_resv->used++;
+
+	trace_xrep_newbt_alloc_block(cur->bc_mp,
+			XFS_FSB_TO_AGNO(cur->bc_mp, fsb),
+			XFS_FSB_TO_AGBNO(cur->bc_mp, fsb),
+			xnr->oinfo.oi_owner);
+
+	if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+		ptr->l = cpu_to_be64(fsb);
+	else
+		ptr->s = cpu_to_be32(XFS_FSB_TO_AGBNO(cur->bc_mp, fsb));
+	return 0;
+}
+
+/*
+ * Estimate proper slack values for a btree that's being reloaded.
+ *
+ * Under most circumstances, we'll take whatever default loading value the
+ * btree bulk loading code calculates for us.  However, there are some
+ * exceptions to this rule:
+ *
+ * (1) If someone turned one of the debug knobs.
+ * (2) If this is a per-AG btree and the AG has less than ~9% space free.
+ * (3) If this is an inode btree and the FS has less than ~9% space free.
+ *
+ * Note that we actually use 3/32 for the comparison to avoid division.
+ */
+void
+xrep_bload_estimate_slack(
+	struct xfs_scrub	*sc,
+	struct xfs_btree_bload	*bload)
+{
+	uint64_t		free;
+	uint64_t		sz;
+
+	/*
+	 * The xfs_globals values are set to -1 (i.e. take the bload defaults)
+	 * unless someone has set them otherwise, so we just pull the values
+	 * here.
+	 */
+	bload->leaf_slack = xfs_globals.bload_leaf_slack;
+	bload->node_slack = xfs_globals.bload_node_slack;
+
+	if (sc->ops->type == ST_PERAG) {
+		free = sc->sa.pag->pagf_freeblks;
+		sz = xfs_ag_block_count(sc->mp, sc->sa.agno);
+	} else {
+		free = percpu_counter_sum(&sc->mp->m_fdblocks);
+		sz = sc->mp->m_sb.sb_dblocks;
+	}
+
+	/* No further changes if there's more than 3/32ths space left. */
+	if (free >= ((sz * 3) >> 5))
+		return;
+
+	/* We're low on space; load the btrees as tightly as possible. */
+	if (bload->leaf_slack < 0)
+		bload->leaf_slack = 0;
+	if (bload->node_slack < 0)
+		bload->node_slack = 0;
+}
+
 /*
  * Reconstructing per-AG Btrees
  *