[dpdk-dev] [PATCH v2 07/12] mbuf: new flag for LRO

[Olivier Matz]

When receiving coalesced packets in virtio, the original size of the
segments is provided. This is a useful information because it allows to
resegment with the same size.

Add a RX new flag in mbuf, that can be set when packets are coalesced by
a hardware or virtual driver when the m->tso_segsz field is valid and is
set to the segment size of original packets.

This flag is used in next commits in the virtio pmd.

Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
---
 doc/guides/rel_notes/release_16_11.rst | 5 +++++
 lib/librte_mbuf/rte_mbuf.c             | 2 ++
 lib/librte_mbuf/rte_mbuf.h             | 7 +++++++
 3 files changed, 14 insertions(+)

diff --git a/doc/guides/rel_notes/release_16_11.rst b/doc/guides/rel_notes/release_16_11.rst
index 2aff84c..a8ad9ab 100644
--- a/doc/guides/rel_notes/release_16_11.rst
+++ b/doc/guides/rel_notes/release_16_11.rst
@@ -66,6 +66,11 @@ New Features
   good, bad, or not present (useful for virtual drivers). This modification
   was done for IP and L4.
 
+* **Added a LRO mbuf flag.**
+
+  Added a new RX LRO mbuf flag, used when packets are coalesced. This
+  flag indicates that the segment size of original packets is known.
+
 Resolved Issues
 ---------------
 
diff --git a/lib/librte_mbuf/rte_mbuf.c b/lib/librte_mbuf/rte_mbuf.c
index c55cb57..61bcd7e 100644
--- a/lib/librte_mbuf/rte_mbuf.c
+++ b/lib/librte_mbuf/rte_mbuf.c
@@ -317,6 +317,7 @@ const char *rte_get_rx_ol_flag_name(uint64_t mask)
 	case PKT_RX_IEEE1588_PTP: return "PKT_RX_IEEE1588_PTP";
 	case PKT_RX_IEEE1588_TMST: return "PKT_RX_IEEE1588_TMST";
 	case PKT_RX_QINQ_STRIPPED: return "PKT_RX_QINQ_STRIPPED";
+	case PKT_RX_LRO: return "PKT_RX_LRO";
 	default: return NULL;
 	}
 }
@@ -349,6 +350,7 @@ int rte_get_rx_ol_flag_list(uint64_t mask, char *buf, size_t buflen)
 		{ PKT_RX_IEEE1588_PTP, PKT_RX_IEEE1588_PTP, NULL },
 		{ PKT_RX_IEEE1588_TMST, PKT_RX_IEEE1588_TMST, NULL },
 		{ PKT_RX_QINQ_STRIPPED, PKT_RX_QINQ_STRIPPED, NULL },
+		{ PKT_RX_LRO, PKT_RX_LRO, NULL },
 	};
 	const char *name;
 	unsigned int i;
diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index 7061cfc..f9d7bfa 100644
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -170,6 +170,13 @@ extern "C" {
  */
 #define PKT_RX_QINQ_PKT      PKT_RX_QINQ_STRIPPED
 
+/**
+ * When packets are coalesced by a hardware or virtual driver, this flag
+ * can be set in the RX mbuf, meaning that the m->tso_segsz field is
+ * valid and is set to the segment size of original packets.
+ */
+#define PKT_RX_LRO           (1ULL << 16)
+
 /* add new RX flags here */
 
 /* add new TX flags here */
-- 
2.8.1