Mcast rewrite no memcpy
use a 32bit mask in the adjacency to AND with the IP address and OR into the rewrite.
Change-Id: I80b0f246c18fd74f3e43c5d49e25833412f34665
Signed-off-by: Neale Ranns <nranns@cisco.com>
diff --git a/src/vnet/rewrite.h b/src/vnet/rewrite.h
index 8435a72..1dea72f 100644
--- a/src/vnet/rewrite.h
+++ b/src/vnet/rewrite.h
@@ -72,20 +72,18 @@
Used for MTU check after packet rewrite. */
u16 max_l3_packet_bytes;
- u16 unused1;
- u8 unused2;
-
+ /* Data-plane flags on the adjacency/rewrite */
vnet_rewrite_flags_t flags;
/* When dynamically writing a multicast destination L2 addresss
- * this is the offset within the address to start writing n
- * bytes of the IP mcast address */
+ * this is the offset from the IP address at which to write in the
+ * IP->MAC address translation.
+ */
u8 dst_mcast_offset;
- /* When dynamically writing a multicast destination L2 addresss
- * this is the number of bytes of the dest IP address to write into
- * the MAC rewrite */
- u8 dst_mcast_n_bytes;
+ /* The mask to apply to the lower 4 bytes of the IP address before ORing
+ * into the destinaiton MAC address */
+ u32 dst_mcast_mask;
/* Rewrite string starting at end and going backwards. */
u8 data[0];
@@ -293,24 +291,24 @@
always_inline void
_vnet_fixup_one_header (vnet_rewrite_header_t * h0,
- u8 * addr, u32 addr_len,
- u8 * packet0, int clear_first_bit)
+ u8 * addr, u32 addr_len, u8 * packet0)
{
- /* location to write to in the packet */
- u8 *p0 = packet0 - h0->dst_mcast_offset;
- u8 *p1 = p0;
- /* location to write from in the L3 dest address */
- u8 *a0 = addr + addr_len - h0->dst_mcast_n_bytes;
+ if (PREDICT_TRUE (h0->dst_mcast_mask))
+ {
+ /* location to write to in the packet */
+ u8 *p0 = packet0 - h0->dst_mcast_offset;
+ u32 *p1 = (u32 *) p0;
+ /* location to copy from in the L3 dest address */
+ u32 *a0 = (u32 *) (addr + addr_len - sizeof (h0->dst_mcast_mask));
- clib_memcpy (p0, a0, h0->dst_mcast_n_bytes);
- if (clear_first_bit)
- *p1 &= 0x7f;
+ *p1 |= (*a0 & h0->dst_mcast_mask);
+ }
}
-#define vnet_fixup_one_header(rw0,addr,p0,clear_first_bit) \
+#define vnet_fixup_one_header(rw0,addr,p0) \
_vnet_fixup_one_header (&((rw0).rewrite_header), \
(u8*)(addr), sizeof((*addr)), \
- (u8*)(p0), (clear_first_bit))
+ (u8*)(p0))
#define VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST ((void *) 0)
/** Deprecated */