Start process of removing the use of the deprecated "M_FLOWID" flag

from the FreeBSD network code. The flag is still kept around in the
"sys/mbuf.h" header file, but does no longer have any users. Instead
the "m_pkthdr.rsstype" field in the mbuf structure is now used to
decide the meaning of the "m_pkthdr.flowid" field. To modify the
"m_pkthdr.rsstype" field please use the existing "M_HASHTYPE_XXX"
macros as defined in the "sys/mbuf.h" header file.

This patch introduces new behaviour in the transmit direction.
Previously network drivers checked if "M_FLOWID" was set in "m_flags"
before using the "m_pkthdr.flowid" field. This check has now now been
replaced by checking if "M_HASHTYPE_GET(m)" is different from
"M_HASHTYPE_NONE". In the future more hashtypes will be added, for
example hashtypes for hardware dedicated flows.

"M_HASHTYPE_OPAQUE" indicates that the "m_pkthdr.flowid" value is
valid and has no particular type. This change removes the need for an
"if" statement in TCP transmit code checking for the presence of a
valid flowid value. The "if" statement mentioned above is now a direct
variable assignment which is then later checked by the respective
network drivers like before.

Additional notes:
- The SCTP code changes will be committed as a separate patch.
- Removal of the "M_FLOWID" flag will also be done separately.
- The FreeBSD version has been bumped.

MFC after:	1 month
Sponsored by:	Mellanox Technologies

1 files changed, 2 insertions, 2 deletions

diff --git a/sys/net/if_lagg.h b/sys/net/if_lagg.h
index e86ed06..8d6decd 100644
--- a/sys/net/if_lagg.h
+++ b/sys/net/if_lagg.h
@@ -143,9 +143,9 @@ struct lagg_reqopts {
 
 	int			ro_opts;		/* Option bitmap */
 #define	LAGG_OPT_NONE			0x00
-#define	LAGG_OPT_USE_FLOWID		0x01		/* use M_FLOWID */
+#define	LAGG_OPT_USE_FLOWID		0x01		/* enable use of flowid */
 /* Pseudo flags which are used in ro_opts but not stored into sc_opts. */
-#define	LAGG_OPT_FLOWIDSHIFT		0x02		/* Set flowid */
+#define	LAGG_OPT_FLOWIDSHIFT		0x02		/* set flowid shift */
 #define	LAGG_OPT_FLOWIDSHIFT_MASK	0x1f		/* flowid is uint32_t */
 #define	LAGG_OPT_LACP_STRICT		0x10		/* LACP strict mode */
 #define	LAGG_OPT_LACP_TXTEST		0x20		/* LACP debug: txtest */