As discussed in the devsummit, introduce two fields in the

struct bio to store classification information, and a hook
for classifier functions that can be called by g_io_request().

This code is from Fabio Checconi as part of his GSOC work.

1 files changed, 13 insertions, 0 deletions

diff --git a/sys/geom/geom.h b/sys/geom/geom.h
index a916ec5..c89083f 100644
--- a/sys/geom/geom.h
+++ b/sys/geom/geom.h
@@ -195,6 +195,17 @@ struct g_provider {
 	u_int			index;
 };
 
+/*
+ * Descriptor of a classifier. We can register a function and
+ * an argument, which is called by g_io_request() on bio's
+ * that are not previously classified.
+ */
+struct g_classifier_hook {
+	TAILQ_ENTRY(g_classifier_hook) link;
+	int			(*func)(void *arg, struct bio *bp);
+	void			*arg;
+};
+
 /* geom_dev.c */
 struct cdev;
 void g_dev_print(void);
@@ -272,6 +283,8 @@ void g_destroy_bio(struct bio *);
 void g_io_deliver(struct bio *bp, int error);
 int g_io_getattr(const char *attr, struct g_consumer *cp, int *len, void *ptr);
 int g_io_flush(struct g_consumer *cp);
+int g_register_classifier(struct g_classifier_hook *hook);
+void g_unregister_classifier(struct g_classifier_hook *hook);
 void g_io_request(struct bio *bp, struct g_consumer *cp);
 struct bio *g_new_bio(void);
 struct bio *g_alloc_bio(void);