From: Darrick J. Wong <darrick.wong@oracle.com>
Date: Wed, 10 Aug 2016 04:38:58 +0000 (+1000)
Subject: xfs: teach rmapbt to support interval queries
X-Git-Tag: v4.8.0-rc1~69
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=890e11746925e83ee06fcf27d676cf71b2301380;p=thirdparty%2Fxfsprogs-dev.git

xfs: teach rmapbt to support interval queries

Source kernel commit: c543838a1e00a5f8791e59ae570b1030d70906f2

Now that the generic btree code supports querying all records within a
range of keys, use that functionality to allow us to ask for all the
extents mapped to a range of physical blocks.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
---

diff --git a/libxfs/xfs_rmap.c b/libxfs/xfs_rmap.c
index 008190907..65df88b53 100644
--- a/libxfs/xfs_rmap.c
+++ b/libxfs/xfs_rmap.c
@@ -181,3 +181,46 @@ out_error:
 	trace_xfs_rmap_map_error(mp, agno, error, _RET_IP_);
 	return error;
 }
+
+struct xfs_rmap_query_range_info {
+	xfs_rmap_query_range_fn	fn;
+	void				*priv;
+};
+
+/* Format btree record and pass to our callback. */
+STATIC int
+xfs_rmap_query_range_helper(
+	struct xfs_btree_cur	*cur,
+	union xfs_btree_rec	*rec,
+	void			*priv)
+{
+	struct xfs_rmap_query_range_info	*query = priv;
+	struct xfs_rmap_irec			irec;
+	int					error;
+
+	error = xfs_rmap_btrec_to_irec(rec, &irec);
+	if (error)
+		return error;
+	return query->fn(cur, &irec, query->priv);
+}
+
+/* Find all rmaps between two keys. */
+int
+xfs_rmap_query_range(
+	struct xfs_btree_cur		*cur,
+	struct xfs_rmap_irec		*low_rec,
+	struct xfs_rmap_irec		*high_rec,
+	xfs_rmap_query_range_fn	fn,
+	void				*priv)
+{
+	union xfs_btree_irec		low_brec;
+	union xfs_btree_irec		high_brec;
+	struct xfs_rmap_query_range_info	query;
+
+	low_brec.r = *low_rec;
+	high_brec.r = *high_rec;
+	query.priv = priv;
+	query.fn = fn;
+	return xfs_btree_query_range(cur, &low_brec, &high_brec,
+			xfs_rmap_query_range_helper, &query);
+}
diff --git a/libxfs/xfs_rmap.h b/libxfs/xfs_rmap.h
index aa39a2a82..34c811a2d 100644
--- a/libxfs/xfs_rmap.h
+++ b/libxfs/xfs_rmap.h
@@ -151,4 +151,13 @@ int xfs_rmap_lookup_eq(struct xfs_btree_cur *cur, xfs_agblock_t bno,
 int xfs_rmap_get_rec(struct xfs_btree_cur *cur, struct xfs_rmap_irec *irec,
 		int *stat);
 
+typedef int (*xfs_rmap_query_range_fn)(
+	struct xfs_btree_cur	*cur,
+	struct xfs_rmap_irec	*rec,
+	void			*priv);
+
+int xfs_rmap_query_range(struct xfs_btree_cur *cur,
+		struct xfs_rmap_irec *low_rec, struct xfs_rmap_irec *high_rec,
+		xfs_rmap_query_range_fn fn, void *priv);
+
 #endif	/* __XFS_RMAP_H__ */