2 files changed, 16 insertions, 0 deletions

diff --git a/sys/kern/subr_sglist.c b/sys/kern/subr_sglist.c
index 71be45b4231d..7c520fda00f5 100644
--- a/sys/kern/subr_sglist.c
+++ b/sys/kern/subr_sglist.c
@@ -467,6 +467,21 @@ sglist_append_mbuf(struct sglist *sg, struct mbuf *m0)
 }
 
 /*
+ * Append the segments that describe a single mbuf to a scatter/gather
+ * list.  If there are insufficient segments, then this fails with
+ * EFBIG.
+ */
+int
+sglist_append_single_mbuf(struct sglist *sg, struct mbuf *m)
+{
+	if ((m->m_flags & M_EXTPG) != 0)
+		return (sglist_append_mbuf_epg(sg, m,
+		    mtod(m, vm_offset_t), m->m_len));
+	else
+		return (sglist_append(sg, m->m_data, m->m_len));
+}
+
+/*
  * Append the segments that describe a buffer spanning an array of VM
  * pages.  The buffer begins at an offset of 'pgoff' in the first
  * page.
diff --git a/sys/sys/sglist.h b/sys/sys/sglist.h
index 82a3ac6ed6ac..bf8aa482e3ce 100644
--- a/sys/sys/sglist.h
+++ b/sys/sys/sglist.h
@@ -94,6 +94,7 @@ int	sglist_append_phys(struct sglist *sg, vm_paddr_t paddr,
 	    size_t len);
 int	sglist_append_sglist(struct sglist *sg, struct sglist *source,
 	    size_t offset, size_t length);
+int	sglist_append_single_mbuf(struct sglist *sg, struct mbuf *m);
 int	sglist_append_uio(struct sglist *sg, struct uio *uio);
 int	sglist_append_user(struct sglist *sg, void *buf, size_t len,
 	    struct thread *td);