summaryrefslogtreecommitdiffstats
path: root/net/core/tso.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/core/tso.c')
-rw-r--r--net/core/tso.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/net/core/tso.c b/net/core/tso.c
new file mode 100644
index 000000000000..8c3203c585b0
--- /dev/null
+++ b/net/core/tso.c
@@ -0,0 +1,77 @@
+#include <linux/export.h>
+#include <net/ip.h>
+#include <net/tso.h>
+
+/* Calculate expected number of TX descriptors */
+int tso_count_descs(struct sk_buff *skb)
+{
+ /* The Marvell Way */
+ return skb_shinfo(skb)->gso_segs * 2 + skb_shinfo(skb)->nr_frags;
+}
+EXPORT_SYMBOL(tso_count_descs);
+
+void tso_build_hdr(struct sk_buff *skb, char *hdr, struct tso_t *tso,
+ int size, bool is_last)
+{
+ struct iphdr *iph;
+ struct tcphdr *tcph;
+ int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
+ int mac_hdr_len = skb_network_offset(skb);
+
+ memcpy(hdr, skb->data, hdr_len);
+ iph = (struct iphdr *)(hdr + mac_hdr_len);
+ iph->id = htons(tso->ip_id);
+ iph->tot_len = htons(size + hdr_len - mac_hdr_len);
+ tcph = (struct tcphdr *)(hdr + skb_transport_offset(skb));
+ tcph->seq = htonl(tso->tcp_seq);
+ tso->ip_id++;
+
+ if (!is_last) {
+ /* Clear all special flags for not last packet */
+ tcph->psh = 0;
+ tcph->fin = 0;
+ tcph->rst = 0;
+ }
+}
+EXPORT_SYMBOL(tso_build_hdr);
+
+void tso_build_data(struct sk_buff *skb, struct tso_t *tso, int size)
+{
+ tso->tcp_seq += size;
+ tso->size -= size;
+ tso->data += size;
+
+ if ((tso->size == 0) &&
+ (tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
+
+ /* Move to next segment */
+ tso->size = frag->size;
+ tso->data = page_address(frag->page.p) + frag->page_offset;
+ tso->next_frag_idx++;
+ }
+}
+EXPORT_SYMBOL(tso_build_data);
+
+void tso_start(struct sk_buff *skb, struct tso_t *tso)
+{
+ int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
+
+ tso->ip_id = ntohs(ip_hdr(skb)->id);
+ tso->tcp_seq = ntohl(tcp_hdr(skb)->seq);
+ tso->next_frag_idx = 0;
+
+ /* Build first data */
+ tso->size = skb_headlen(skb) - hdr_len;
+ tso->data = skb->data + hdr_len;
+ if ((tso->size == 0) &&
+ (tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];
+
+ /* Move to next segment */
+ tso->size = frag->size;
+ tso->data = page_address(frag->page.p) + frag->page_offset;
+ tso->next_frag_idx++;
+ }
+}
+EXPORT_SYMBOL(tso_start);