dd a 24 bits wide ext_flags field to m_ext by reducing ext_type

to 8 bits.  ext_type is an enumerator and the number of types we
have is a mere dozen.

A couple of ext_types are renumbered to fit within 8 bits.

EXT_VENDOR[1-4] and EXT_EXP[1-4] types for vendor-internal and
experimental local mapping.

The ext_flags field is currently unused but has a couple of flags
already defined for future use.  Again vendor and experimental
flags are provided for local mapping.

EXT_FLAG_BITS is provided for the printf(9) %b identifier.

Initialize and copy ext_flags in the relevant mbuf functions.

Improve alignment and packing of struct m_ext on 32 and 64 archs
by carefully sorting the fields.

1 files changed, 1 insertions, 0 deletions

diff --git a/sys/kern/kern_mbuf.c b/sys/kern/kern_mbuf.c
index c01f432..85d62ea 100644
--- a/sys/kern/kern_mbuf.c
+++ b/sys/kern/kern_mbuf.c
@@ -547,6 +547,7 @@ mb_ctor_clust(void *mem, int size, void *arg, int how)
 		m->m_ext.ext_arg2 = NULL;
 		m->m_ext.ext_size = size;
 		m->m_ext.ext_type = type;
+		m->m_ext.ext_flags = 0;
 		m->m_ext.ref_cnt = refcnt;
 	}