xen-balloon: Move core balloon functionality out of module

The basic functionality of ballooning pages is useful for Xen drivers in
general. Rather than require a dependency on the balloon module, split
the functionality that is reused into the core. The balloon module is
still required to follow ballooning requests from xenstore or to view
balloon statistics in sysfs.

Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/include/xen/balloon.h b/include/xen/balloon.h
new file mode 100644
index 000000000000..f72e4794ec77
--- /dev/null
+++ b/include/xen/balloon.h
@@ -0,0 +1,22 @@
+/******************************************************************************
+ * Xen balloon functionality
+ */
+
+#define RETRY_UNLIMITED 0
+
+struct balloon_stats {
+        /* We aim for 'current allocation' == 'target allocation'. */
+        unsigned long current_pages;
+        unsigned long target_pages;
+        /* Number of pages in high- and low-memory balloons. */
+        unsigned long balloon_low;
+        unsigned long balloon_high;
+        unsigned long schedule_delay;
+        unsigned long max_schedule_delay;
+        unsigned long retry_count;
+        unsigned long max_retry_count;
+};
+
+extern struct balloon_stats balloon_stats;
+
+void balloon_set_new_target(unsigned long target);