pNFS: consolidate the different range intersection tests
Both pnfs.c and the flexfiles code have their own versions of the
range intersection testing, and the "end_offset" helper.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 44cad8a..337dad3 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -560,6 +560,38 @@ pnfs_copy_range(struct pnfs_layout_range *dst,
memcpy(dst, src, sizeof(*dst));
}
+static inline u64
+pnfs_end_offset(u64 start, u64 len)
+{
+ if (NFS4_MAX_UINT64 - start <= len)
+ return NFS4_MAX_UINT64;
+ return start + len;
+}
+
+/*
+ * Are 2 ranges intersecting?
+ * start1 end1
+ * [----------------------------------)
+ * start2 end2
+ * [----------------)
+ */
+static inline bool
+pnfs_is_range_intersecting(u64 start1, u64 end1, u64 start2, u64 end2)
+{
+ return (end1 == NFS4_MAX_UINT64 || start2 < end1) &&
+ (end2 == NFS4_MAX_UINT64 || start1 < end2);
+}
+
+static inline bool
+pnfs_lseg_range_intersecting(const struct pnfs_layout_range *l1,
+ const struct pnfs_layout_range *l2)
+{
+ u64 end1 = pnfs_end_offset(l1->offset, l1->length);
+ u64 end2 = pnfs_end_offset(l2->offset, l2->length);
+
+ return pnfs_is_range_intersecting(l1->offset, end1, l2->offset, end2);
+}
+
extern unsigned int layoutstats_timer;
#ifdef NFS_DEBUG