diff options
Diffstat (limited to 'drivers/net/realtek-dsa/dsa_priv.h')
| -rw-r--r-- | drivers/net/realtek-dsa/dsa_priv.h | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/net/realtek-dsa/dsa_priv.h b/drivers/net/realtek-dsa/dsa_priv.h new file mode 100644 index 0000000000..4cda518310 --- /dev/null +++ b/drivers/net/realtek-dsa/dsa_priv.h @@ -0,0 +1,77 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* SPDX-FileCopyrightText: (c) 2008-2009 Marvell Semiconductor */ + +#ifndef __DSA_PRIV_H +#define __DSA_PRIV_H + +#include <net.h> +#include <linux/string.h> + + +/* Helper for removing DSA header tags from packets in the RX path. + * Must not be called before skb_pull(len). + * + * Before: + * packet + * | + * v + * | | | | | | | | | | | | | | | | | | | + * +-----------------------+-----------------------+---------------+-------+ + * | Destination MAC | Source MAC | DSA header | EType | + * +-----------------------+-----------------------+---------------+-------+ + * | | + * <----- len -----> + * After: + * + * <----- len -----> + * | + * >>>>>>> v + * >>>>>>> | | | | | | | | | | | | | | | + * >>>>>>> +-----------------------+-----------------------+-------+ + * >>>>>>> | Destination MAC | Source MAC | EType | + * +-----------------------+-----------------------+-------+ + * + */ +static inline void dsa_strip_etype_header(void *packet, int len) +{ + memmove(packet + len, packet, 2 * ETH_ALEN); +} + +/* Helper for creating space for DSA header tags in TX path packets. + * + * Before: + * + * <<<<<<< | | | | | | | | | | | | | | | + * ^ <<<<<<< +-----------------------+-----------------------+-------+ + * | <<<<<<< | Destination MAC | Source MAC | EType | + * | +-----------------------+-----------------------+-------+ + * <----- len -----> + * | + * | + * packet + * + * After: + * + * | | | | | | | | | | | | | | | | | | | + * +-----------------------+-----------------------+---------------+-------+ + * | Destination MAC | Source MAC | DSA header | EType | + * +-----------------------+-----------------------+---------------+-------+ + * ^ | | + * | <----- len -----> + * packet + */ +static inline void dsa_alloc_etype_header(void *packet, int len) +{ + memmove(packet, packet + len, 2 * ETH_ALEN); +} + +/* On TX, skb->data points to skb_mac_header(skb), which means that EtherType + * header taggers start exactly where the EtherType is (the EtherType is + * treated as part of the DSA header). + */ +static inline void *dsa_etype_header_pos(void *packet) +{ + return packet + 2 * ETH_ALEN; +} + +#endif |