linux/drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2013-2018, 2021, The Linux Foundation. All rights reserved.
 *
 * RMNET Data MAP protocol
 */

#include <linux/netdevice.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <net/ip6_checksum.h>
#include <linux/bitfield.h>
#include "rmnet_config.h"
#include "rmnet_map.h"
#include "rmnet_private.h"
#include "rmnet_vnd.h"

#define RMNET_MAP_DEAGGR_SPACING …
#define RMNET_MAP_DEAGGR_HEADROOM …

static __sum16 *rmnet_map_get_csum_field(unsigned char protocol,
					 const void *txporthdr)
{ … }

static int
rmnet_map_ipv4_dl_csum_trailer(struct sk_buff *skb,
			       struct rmnet_map_dl_csum_trailer *csum_trailer,
			       struct rmnet_priv *priv)
{ … }

#if IS_ENABLED(CONFIG_IPV6)
static int
rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
			       struct rmnet_map_dl_csum_trailer *csum_trailer,
			       struct rmnet_priv *priv)
{ … }
#else
static int
rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
			       struct rmnet_map_dl_csum_trailer *csum_trailer,
			       struct rmnet_priv *priv)
{
	return 0;
}
#endif

static void rmnet_map_complement_ipv4_txporthdr_csum_field(struct iphdr *ip4h)
{ … }

static void
rmnet_map_ipv4_ul_csum_header(struct iphdr *iphdr,
			      struct rmnet_map_ul_csum_header *ul_header,
			      struct sk_buff *skb)
{ … }

#if IS_ENABLED(CONFIG_IPV6)
static void
rmnet_map_complement_ipv6_txporthdr_csum_field(struct ipv6hdr *ip6h)
{ … }

static void
rmnet_map_ipv6_ul_csum_header(struct ipv6hdr *ipv6hdr,
			      struct rmnet_map_ul_csum_header *ul_header,
			      struct sk_buff *skb)
{ … }
#else
static void
rmnet_map_ipv6_ul_csum_header(void *ip6hdr,
			      struct rmnet_map_ul_csum_header *ul_header,
			      struct sk_buff *skb)
{
}
#endif

static void rmnet_map_v5_checksum_uplink_packet(struct sk_buff *skb,
						struct rmnet_port *port,
						struct net_device *orig_dev)
{ … }

/* Adds MAP header to front of skb->data
 * Padding is calculated and set appropriately in MAP header. Mux ID is
 * initialized to 0.
 */
struct rmnet_map_header *rmnet_map_add_map_header(struct sk_buff *skb,
						  int hdrlen,
						  struct rmnet_port *port,
						  int pad)
{ … }

/* Deaggregates a single packet
 * A whole new buffer is allocated for each portion of an aggregated frame.
 * Caller should keep calling deaggregate() on the source skb until 0 is
 * returned, indicating that there are no more packets to deaggregate. Caller
 * is responsible for freeing the original skb.
 */
struct sk_buff *rmnet_map_deaggregate(struct sk_buff *skb,
				      struct rmnet_port *port)
{ … }

/* Validates packet checksums. Function takes a pointer to
 * the beginning of a buffer which contains the IP payload +
 * padding + checksum trailer.
 * Only IPv4 and IPv6 are supported along with TCP & UDP.
 * Fragmented or tunneled packets are not supported.
 */
int rmnet_map_checksum_downlink_packet(struct sk_buff *skb, u16 len)
{ … }

static void rmnet_map_v4_checksum_uplink_packet(struct sk_buff *skb,
						struct net_device *orig_dev)
{ … }

/* Generates UL checksum meta info header for IPv4 and IPv6 over TCP and UDP
 * packets that are supported for UL checksum offload.
 */
void rmnet_map_checksum_uplink_packet(struct sk_buff *skb,
				      struct rmnet_port *port,
				      struct net_device *orig_dev,
				      int csum_type)
{ … }

/* Process a MAPv5 packet header */
int rmnet_map_process_next_hdr_packet(struct sk_buff *skb,
				      u16 len)
{ … }

#define RMNET_AGG_BYPASS_TIME_NSEC …

static void reset_aggr_params(struct rmnet_port *port)
{ … }

static void rmnet_send_skb(struct rmnet_port *port, struct sk_buff *skb)
{ … }

static void rmnet_map_flush_tx_packet_work(struct work_struct *work)
{ … }

static enum hrtimer_restart rmnet_map_flush_tx_packet_queue(struct hrtimer *t)
{ … }

unsigned int rmnet_map_tx_aggregate(struct sk_buff *skb, struct rmnet_port *port,
				    struct net_device *orig_dev)
{ … }

void rmnet_map_update_ul_agg_config(struct rmnet_port *port, u32 size,
				    u32 count, u32 time)
{ … }

void rmnet_map_tx_aggregate_init(struct rmnet_port *port)
{ … }

void rmnet_map_tx_aggregate_exit(struct rmnet_port *port)
{ … }