1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /****************************************************************************
3  * Driver for Solarflare network controllers and boards
4  * Copyright 2005-2006 Fen Systems Ltd.
5  * Copyright 2006-2015 Solarflare Communications Inc.
6  */
7 
8 #ifndef EFX_TX_H
9 #define EFX_TX_H
10 
11 #include <linux/types.h>
12 
13 /* Driver internal tx-path related declarations. */
14 
15 unsigned int efx_tx_limit_len(struct efx_tx_queue *tx_queue,
16 			      dma_addr_t dma_addr, unsigned int len);
17 
18 u8 *efx_tx_get_copy_buffer_limited(struct efx_tx_queue *tx_queue,
19 				   struct efx_tx_buffer *buffer, size_t len);
20 
21 /* What TXQ type will satisfy the checksum offloads required for this skb? */
efx_tx_csum_type_skb(struct sk_buff * skb)22 static inline unsigned int efx_tx_csum_type_skb(struct sk_buff *skb)
23 {
24 	if (skb->ip_summed != CHECKSUM_PARTIAL)
25 		return 0; /* no checksum offload */
26 
27 	if (skb->encapsulation &&
28 	    skb_checksum_start_offset(skb) == skb_inner_transport_offset(skb)) {
29 		/* we only advertise features for IPv4 and IPv6 checksums on
30 		 * encapsulated packets, so if the checksum is for the inner
31 		 * packet, it must be one of them; no further checking required.
32 		 */
33 
34 		/* Do we also need to offload the outer header checksum? */
35 		if (skb_shinfo(skb)->gso_segs > 1 &&
36 		    !(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
37 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
38 			return EFX_TXQ_TYPE_OUTER_CSUM | EFX_TXQ_TYPE_INNER_CSUM;
39 		return EFX_TXQ_TYPE_INNER_CSUM;
40 	}
41 
42 	/* similarly, we only advertise features for IPv4 and IPv6 checksums,
43 	 * so it must be one of them. No need for further checks.
44 	 */
45 	return EFX_TXQ_TYPE_OUTER_CSUM;
46 }
47 #endif /* EFX_TX_H */
48