tap: refactor existing flags

Type: refactor

This patch refactor the existing flags and also add a new
flag for packet coalescing.

Change-Id: Ic826e4c81313f26d87c475cdf666b06cbed60a3a
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>

3 files changed, 26 insertions, 12 deletions

diff --git a/src/vnet/devices/tap/cli.c b/src/vnet/devices/tap/cli.c
index 486cd9fda21..34897ea7c5d 100644
--- a/src/vnet/devices/tap/cli.c
+++ b/src/vnet/devices/tap/cli.c
@@ -90,6 +90,8 @@ tap_create_command_fn (vlib_main_t * vm, unformat_input_t * input,
 	    args.tap_flags &= ~TAP_FLAG_GSO;
 	  else if (unformat (line_input, "gso"))
 	    args.tap_flags |= TAP_FLAG_GSO;
+	  else if (unformat (line_input, "gro-coalesce"))
+	    args.tap_flags |= TAP_FLAG_GRO_COALESCE;
 	  else if (unformat (line_input, "csum-offload"))
 	    args.tap_flags |= TAP_FLAG_CSUM_OFFLOAD;
 	  else if (unformat (line_input, "persist"))
@@ -138,7 +140,8 @@ VLIB_CLI_COMMAND (tap_create_command, static) = {
     "[host-ip4-addr <ip4addr/mask>] [host-ip6-addr <ip6-addr>] "
     "[host-ip4-gw <ip4-addr>] [host-ip6-gw <ip6-addr>] "
     "[host-mac-addr <host-mac-address>] [host-if-name <name>] "
-    "[host-mtu-size <size>] [no-gso|gso|csum-offload] [persist] [attach] [tun]",
+    "[host-mtu-size <size>] [no-gso|gso|csum-offload|gro-coalesce] "
+    "[persist] [attach] [tun]",
   .function = tap_create_command_fn,
 };
 /* *INDENT-ON* */
diff --git a/src/vnet/devices/tap/tap.h b/src/vnet/devices/tap/tap.h
index c1ac7a61229..a9cd4766c3c 100644
--- a/src/vnet/devices/tap/tap.h
+++ b/src/vnet/devices/tap/tap.h
@@ -22,6 +22,21 @@
 #define MIN(x,y) (((x)<(y))?(x):(y))
 #endif
 
+#define foreach_tapv2_flags  \
+  _ (GSO, 0)                 \
+  _ (CSUM_OFFLOAD, 1)        \
+  _ (PERSIST, 2)             \
+  _ (ATTACH, 3)              \
+  _ (TUN, 4)                 \
+  _ (GRO_COALESCE, 5)
+
+typedef enum
+{
+#define _(a, b) TAP_FLAG_##a = (1 << b),
+  foreach_tapv2_flags
+#undef _
+} tap_flag_t;
+
 typedef struct
 {
   u32 id;
@@ -31,11 +46,6 @@ typedef struct
   u16 rx_ring_sz;
   u16 tx_ring_sz;
   u32 tap_flags;
-#define TAP_FLAG_GSO (1 << 0)
-#define TAP_FLAG_CSUM_OFFLOAD (1 << 1)
-#define TAP_FLAG_PERSIST (1 << 2)
-#define TAP_FLAG_ATTACH (1 << 3)
-#define TAP_FLAG_TUN (1 << 4)
   u8 *host_namespace;
   u8 *host_if_name;
   mac_address_t host_mac_addr;
diff --git a/src/vnet/devices/tap/tapv2.api b/src/vnet/devices/tap/tapv2.api
index 61b6720a0d3..94e1a7c00c2 100644
--- a/src/vnet/devices/tap/tapv2.api
+++ b/src/vnet/devices/tap/tapv2.api
@@ -19,18 +19,19 @@
     the Linux kernel TAP device driver
 */
 
-option version = "3.0.0";
+option version = "4.0.0";
 
 import "vnet/interface_types.api";
 import "vnet/ethernet/ethernet_types.api";
 import "vnet/ip/ip_types.api";
 
 enum tap_flags {
-        TAP_FLAG_GSO = 1,
-        TAP_FLAG_CSUM_OFFLOAD = 2,
-	TAP_FLAG_PERSIST = 4,
-	TAP_FLAG_ATTACH = 8,
-	TAP_FLAG_TUN = 16,
+        TAP_API_FLAG_GSO = 1, /* enable gso on the interface */
+        TAP_API_FLAG_CSUM_OFFLOAD = 2, /* enable checksum offload without gso on the interface */
+        TAP_API_FLAG_PERSIST = 4, /* make the interface persistence to exist in linux even vpp crash/restart */
+        TAP_API_FLAG_ATTACH = 8,  /* attach to the existing persistence interface after vpp crash/restart */
+        TAP_API_FLAG_TUN = 16,  /* create TUN interface instead of tap */
+        TAP_API_FLAG_GRO_COALESCE = 32, /* enable packet coalescing on tx side, provided gso enabled */
 };
 
 /** \brief Initialize a new tap interface with the given parameters