From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- drivers/net/arcnet/capmode.c | 268 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 268 insertions(+) create mode 100644 drivers/net/arcnet/capmode.c (limited to 'drivers/net/arcnet/capmode.c') diff --git a/drivers/net/arcnet/capmode.c b/drivers/net/arcnet/capmode.c new file mode 100644 index 000000000..b780be6f4 --- /dev/null +++ b/drivers/net/arcnet/capmode.c @@ -0,0 +1,268 @@ +/* + * Linux ARCnet driver - "cap mode" packet encapsulation. + * It adds sequence numbers to packets for communicating between a user space + * application and the driver. After a transmit it sends a packet with protocol + * byte 0 back up to the userspace containing the sequence number of the packet + * plus the transmit-status on the ArcNet. + * + * Written 2002-4 by Esben Nielsen, Vestas Wind Systems A/S + * Derived from arc-rawmode.c by Avery Pennarun. + * arc-rawmode was in turned based on skeleton.c, see below. + * + * ********************** + * + * The original copyright of skeleton.c was as follows: + * + * skeleton.c Written 1993 by Donald Becker. + * Copyright 1993 United States Government as represented by the + * Director, National Security Agency. This software may only be used + * and distributed according to the terms of the GNU General Public License as + * modified by SRC, incorporated herein by reference. + * + * ********************** + * + * For more details, see drivers/net/arcnet.c + * + * ********************** + */ + +#define pr_fmt(fmt) "arcnet:" KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include + +#include "arcdevice.h" + +/* packet receiver */ +static void rx(struct net_device *dev, int bufnum, + struct archdr *pkthdr, int length) +{ + struct arcnet_local *lp = netdev_priv(dev); + struct sk_buff *skb; + struct archdr *pkt = pkthdr; + char *pktbuf, *pkthdrbuf; + int ofs; + + arc_printk(D_DURING, dev, "it's a raw(cap) packet (length=%d)\n", + length); + + if (length >= MinTU) + ofs = 512 - length; + else + ofs = 256 - length; + + skb = alloc_skb(length + ARC_HDR_SIZE + sizeof(int), GFP_ATOMIC); + if (!skb) { + dev->stats.rx_dropped++; + return; + } + skb_put(skb, length + ARC_HDR_SIZE + sizeof(int)); + skb->dev = dev; + skb_reset_mac_header(skb); + pkt = (struct archdr *)skb_mac_header(skb); + skb_pull(skb, ARC_HDR_SIZE); + + /* up to sizeof(pkt->soft) has already been copied from the card + * squeeze in an int for the cap encapsulation + * use these variables to be sure we count in bytes, not in + * sizeof(struct archdr) + */ + pktbuf = (char *)pkt; + pkthdrbuf = (char *)pkthdr; + memcpy(pktbuf, pkthdrbuf, ARC_HDR_SIZE + sizeof(pkt->soft.cap.proto)); + memcpy(pktbuf + ARC_HDR_SIZE + sizeof(pkt->soft.cap.proto) + sizeof(int), + pkthdrbuf + ARC_HDR_SIZE + sizeof(pkt->soft.cap.proto), + sizeof(struct archdr) - ARC_HDR_SIZE - sizeof(pkt->soft.cap.proto)); + + if (length > sizeof(pkt->soft)) + lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft), + pkt->soft.raw + sizeof(pkt->soft) + + sizeof(int), + length - sizeof(pkt->soft)); + + if (BUGLVL(D_SKB)) + arcnet_dump_skb(dev, skb, "rx"); + + skb->protocol = cpu_to_be16(ETH_P_ARCNET); + netif_rx(skb); +} + +/* Create the ARCnet hard/soft headers for cap mode. + * There aren't any soft headers in cap mode - not even the protocol id. + */ +static int build_header(struct sk_buff *skb, + struct net_device *dev, + unsigned short type, + uint8_t daddr) +{ + int hdr_size = ARC_HDR_SIZE; + struct archdr *pkt = skb_push(skb, hdr_size); + + arc_printk(D_PROTO, dev, "Preparing header for cap packet %x.\n", + *((int *)&pkt->soft.cap.cookie[0])); + + /* Set the source hardware address. + * + * This is pretty pointless for most purposes, but it can help in + * debugging. ARCnet does not allow us to change the source address in + * the actual packet sent) + */ + pkt->hard.source = *dev->dev_addr; + + /* see linux/net/ethernet/eth.c to see where I got the following */ + + if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) { + /* FIXME: fill in the last byte of the dest ipaddr here to + * better comply with RFC1051 in "noarp" mode. + */ + pkt->hard.dest = 0; + return hdr_size; + } + /* otherwise, just fill it in and go! */ + pkt->hard.dest = daddr; + + return hdr_size; /* success */ +} + +static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length, + int bufnum) +{ + struct arcnet_local *lp = netdev_priv(dev); + struct arc_hardware *hard = &pkt->hard; + int ofs; + + /* hard header is not included in packet length */ + length -= ARC_HDR_SIZE; + /* And neither is the cookie field */ + length -= sizeof(int); + + arc_printk(D_DURING, dev, "prepare_tx: txbufs=%d/%d/%d\n", + lp->next_tx, lp->cur_tx, bufnum); + + arc_printk(D_PROTO, dev, "Sending for cap packet %x.\n", + *((int *)&pkt->soft.cap.cookie[0])); + + if (length > XMTU) { + /* should never happen! other people already check for this. */ + arc_printk(D_NORMAL, dev, "Bug! prepare_tx with size %d (> %d)\n", + length, XMTU); + length = XMTU; + } + if (length > MinTU) { + hard->offset[0] = 0; + hard->offset[1] = ofs = 512 - length; + } else if (length > MTU) { + hard->offset[0] = 0; + hard->offset[1] = ofs = 512 - length - 3; + } else { + hard->offset[0] = ofs = 256 - length; + } + + arc_printk(D_DURING, dev, "prepare_tx: length=%d ofs=%d\n", + length, ofs); + + /* Copy the arcnet-header + the protocol byte down: */ + lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE); + lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft.cap.proto, + sizeof(pkt->soft.cap.proto)); + + /* Skip the extra integer we have written into it as a cookie + * but write the rest of the message: + */ + lp->hw.copy_to_card(dev, bufnum, ofs + 1, + ((unsigned char *)&pkt->soft.cap.mes), length - 1); + + lp->lastload_dest = hard->dest; + + return 1; /* done */ +} + +static int ack_tx(struct net_device *dev, int acked) +{ + struct arcnet_local *lp = netdev_priv(dev); + struct sk_buff *ackskb; + struct archdr *ackpkt; + int length = sizeof(struct arc_cap); + + arc_printk(D_DURING, dev, "capmode: ack_tx: protocol: %x: result: %d\n", + lp->outgoing.skb->protocol, acked); + + if (BUGLVL(D_SKB)) + arcnet_dump_skb(dev, lp->outgoing.skb, "ack_tx"); + + /* Now alloc a skb to send back up through the layers: */ + ackskb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC); + if (!ackskb) + goto free_outskb; + + skb_put(ackskb, length + ARC_HDR_SIZE); + ackskb->dev = dev; + + skb_reset_mac_header(ackskb); + ackpkt = (struct archdr *)skb_mac_header(ackskb); + /* skb_pull(ackskb, ARC_HDR_SIZE); */ + + skb_copy_from_linear_data(lp->outgoing.skb, ackpkt, + ARC_HDR_SIZE + sizeof(struct arc_cap)); + ackpkt->soft.cap.proto = 0; /* using protocol 0 for acknowledge */ + ackpkt->soft.cap.mes.ack = acked; + + arc_printk(D_PROTO, dev, "Acknowledge for cap packet %x.\n", + *((int *)&ackpkt->soft.cap.cookie[0])); + + ackskb->protocol = cpu_to_be16(ETH_P_ARCNET); + + if (BUGLVL(D_SKB)) + arcnet_dump_skb(dev, ackskb, "ack_tx_recv"); + netif_rx(ackskb); + +free_outskb: + dev_kfree_skb_irq(lp->outgoing.skb); + lp->outgoing.proto = NULL; + /* We are always finished when in this protocol */ + + return 0; +} + +static struct ArcProto capmode_proto = { + .suffix = 'r', + .mtu = XMTU, + .rx = rx, + .build_header = build_header, + .prepare_tx = prepare_tx, + .ack_tx = ack_tx +}; + +static int __init capmode_module_init(void) +{ + int count; + + pr_info("cap mode (`c') encapsulation support loaded\n"); + + for (count = 1; count <= 8; count++) + if (arc_proto_map[count] == arc_proto_default) + arc_proto_map[count] = &capmode_proto; + + /* for cap mode, we only set the bcast proto if there's no better one */ + if (arc_bcast_proto == arc_proto_default) + arc_bcast_proto = &capmode_proto; + + arc_proto_default = &capmode_proto; + arc_raw_proto = &capmode_proto; + + return 0; +} + +static void __exit capmode_module_exit(void) +{ + arcnet_unregister_proto(&capmode_proto); +} +module_init(capmode_module_init); +module_exit(capmode_module_exit); + +MODULE_LICENSE("GPL"); -- cgit v1.2.3