xenstore: Add brief notice regarding xenstore protocol limits to xs.h.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>

diff --git a/tools/xenstore/xs.h b/tools/xenstore/xs.h
index 629395291ac7d7b871257b15a87e2aba1fb9d21f..bd36a0b3502134d56a1c15be0459c70d2440d3d0 100644 (file)
--- a/tools/xenstore/xs.h
+++ b/tools/xenstore/xs.h
@@ -27,6 +27,11 @@
 struct xs_handle;
 typedef uint32_t xs_transaction_t;
 
+/* IMPORTANT: For details on xenstore protocol limits, see
+ * docs/misc/xenstore.txt in the Xen public source repository, and use the
+ * XENSTORE_*_MAX limit macros defined in xen/io/xs_wire.h.
+ */
+
 /* On failure, these routines set errno. */
 
 /* Connect to the xs daemon.