2 files changed, 19 insertions, 0 deletions

diff --git a/sys/geom/geom.h b/sys/geom/geom.h
index 493221b9784e..36acaf55dd45 100644
--- a/sys/geom/geom.h
+++ b/sys/geom/geom.h
@@ -222,6 +222,7 @@ void g_io_request(struct bio *bp, struct g_consumer *cp);
 int g_io_setattr(const char *attr, struct g_consumer *cp, int len, void *ptr);
 struct bio *g_new_bio(void);
 void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error);
+int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length);
 
 /* geom_kern.c / geom_kernsim.c */
 
diff --git a/sys/geom/geom_io.c b/sys/geom/geom_io.c
index 7d7eed1fc638..f86c5e262882 100644
--- a/sys/geom/geom_io.c
+++ b/sys/geom/geom_io.c
@@ -387,3 +387,21 @@ g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error)
         } while (errorc == EBUSY);
 	return (ptr);
 }
+
+int
+g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length)
+{
+	struct bio *bp;
+	int error;
+
+	bp = g_new_bio();
+	bp->bio_cmd = BIO_WRITE;
+	bp->bio_done = NULL;
+	bp->bio_offset = offset;
+	bp->bio_length = length;
+	bp->bio_data = ptr;
+	g_io_request(bp, cp);
+	error = biowait(bp, "gwrite");
+	g_destroy_bio(bp);
+	return (error);
+}