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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 17:59:32 +00:00
![Johannes Berg](/assets/img/avatar_default.png)
It seems like a historic accident that these return unsigned char *, and in many places that means casts are required, more often than not. Make these functions return void * and remove all the casts across the tree, adding a (u8 *) cast only where the unsigned char pointer was used directly, all done with the following spatch: @@ expression SKB, LEN; typedef u8; identifier fn = { skb_push, __skb_push, skb_push_rcsum }; @@ - *(fn(SKB, LEN)) + *(u8 *)fn(SKB, LEN) @@ expression E, SKB, LEN; identifier fn = { skb_push, __skb_push, skb_push_rcsum }; type T; @@ - E = ((T *)(fn(SKB, LEN))) + E = fn(SKB, LEN) @@ expression SKB, LEN; identifier fn = { skb_push, __skb_push, skb_push_rcsum }; @@ - fn(SKB, LEN)[0] + *(u8 *)fn(SKB, LEN) Note that the last part there converts from push(...)[0] to the more idiomatic *(u8 *)push(...). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
550 lines
14 KiB
C
550 lines
14 KiB
C
/*
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* INET An implementation of the TCP/IP protocol suite for the LINUX
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* operating system. INET is implemented using the BSD Socket
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* interface as the means of communication with the user level.
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*
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* Ethernet-type device handling.
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*
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* Version: @(#)eth.c 1.0.7 05/25/93
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*
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* Authors: Ross Biro
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* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
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* Mark Evans, <evansmp@uhura.aston.ac.uk>
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* Florian La Roche, <rzsfl@rz.uni-sb.de>
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* Alan Cox, <gw4pts@gw4pts.ampr.org>
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*
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* Fixes:
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* Mr Linux : Arp problems
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* Alan Cox : Generic queue tidyup (very tiny here)
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* Alan Cox : eth_header ntohs should be htons
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* Alan Cox : eth_rebuild_header missing an htons and
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* minor other things.
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* Tegge : Arp bug fixes.
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* Florian : Removed many unnecessary functions, code cleanup
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* and changes for new arp and skbuff.
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* Alan Cox : Redid header building to reflect new format.
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* Alan Cox : ARP only when compiled with CONFIG_INET
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* Greg Page : 802.2 and SNAP stuff.
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* Alan Cox : MAC layer pointers/new format.
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* Paul Gortmaker : eth_copy_and_sum shouldn't csum padding.
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* Alan Cox : Protect against forwarding explosions with
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* older network drivers and IFF_ALLMULTI.
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* Christer Weinigel : Better rebuild header message.
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* Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup().
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/mm.h>
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#include <linux/socket.h>
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#include <linux/in.h>
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#include <linux/inet.h>
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#include <linux/ip.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/skbuff.h>
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#include <linux/errno.h>
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#include <linux/init.h>
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#include <linux/if_ether.h>
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#include <linux/of_net.h>
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#include <linux/pci.h>
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#include <net/dst.h>
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#include <net/arp.h>
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#include <net/sock.h>
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#include <net/ipv6.h>
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#include <net/ip.h>
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#include <net/dsa.h>
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#include <net/flow_dissector.h>
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#include <linux/uaccess.h>
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#include <net/pkt_sched.h>
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__setup("ether=", netdev_boot_setup);
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/**
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* eth_header - create the Ethernet header
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* @skb: buffer to alter
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* @dev: source device
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* @type: Ethernet type field
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* @daddr: destination address (NULL leave destination address)
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* @saddr: source address (NULL use device source address)
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* @len: packet length (<= skb->len)
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*
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*
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* Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length
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* in here instead.
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*/
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int eth_header(struct sk_buff *skb, struct net_device *dev,
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unsigned short type,
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const void *daddr, const void *saddr, unsigned int len)
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{
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struct ethhdr *eth = skb_push(skb, ETH_HLEN);
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if (type != ETH_P_802_3 && type != ETH_P_802_2)
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eth->h_proto = htons(type);
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else
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eth->h_proto = htons(len);
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/*
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* Set the source hardware address.
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*/
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if (!saddr)
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saddr = dev->dev_addr;
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memcpy(eth->h_source, saddr, ETH_ALEN);
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if (daddr) {
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memcpy(eth->h_dest, daddr, ETH_ALEN);
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return ETH_HLEN;
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}
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/*
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* Anyway, the loopback-device should never use this function...
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*/
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if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
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eth_zero_addr(eth->h_dest);
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return ETH_HLEN;
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}
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return -ETH_HLEN;
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}
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EXPORT_SYMBOL(eth_header);
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/**
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* eth_get_headlen - determine the length of header for an ethernet frame
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* @data: pointer to start of frame
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* @len: total length of frame
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*
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* Make a best effort attempt to pull the length for all of the headers for
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* a given frame in a linear buffer.
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*/
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u32 eth_get_headlen(void *data, unsigned int len)
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{
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const unsigned int flags = FLOW_DISSECTOR_F_PARSE_1ST_FRAG;
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const struct ethhdr *eth = (const struct ethhdr *)data;
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struct flow_keys keys;
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/* this should never happen, but better safe than sorry */
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if (unlikely(len < sizeof(*eth)))
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return len;
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/* parse any remaining L2/L3 headers, check for L4 */
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if (!skb_flow_dissect_flow_keys_buf(&keys, data, eth->h_proto,
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sizeof(*eth), len, flags))
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return max_t(u32, keys.control.thoff, sizeof(*eth));
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/* parse for any L4 headers */
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return min_t(u32, __skb_get_poff(NULL, data, &keys, len), len);
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}
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EXPORT_SYMBOL(eth_get_headlen);
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/**
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* eth_type_trans - determine the packet's protocol ID.
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* @skb: received socket data
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* @dev: receiving network device
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*
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* The rule here is that we
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* assume 802.3 if the type field is short enough to be a length.
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* This is normal practice and works for any 'now in use' protocol.
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*/
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__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
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{
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unsigned short _service_access_point;
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const unsigned short *sap;
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const struct ethhdr *eth;
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skb->dev = dev;
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skb_reset_mac_header(skb);
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eth = (struct ethhdr *)skb->data;
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skb_pull_inline(skb, ETH_HLEN);
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if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) {
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if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast))
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skb->pkt_type = PACKET_BROADCAST;
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else
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skb->pkt_type = PACKET_MULTICAST;
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}
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else if (unlikely(!ether_addr_equal_64bits(eth->h_dest,
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dev->dev_addr)))
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skb->pkt_type = PACKET_OTHERHOST;
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/*
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* Some variants of DSA tagging don't have an ethertype field
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* at all, so we check here whether one of those tagging
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* variants has been configured on the receiving interface,
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* and if so, set skb->protocol without looking at the packet.
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*/
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if (unlikely(netdev_uses_dsa(dev)))
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return htons(ETH_P_XDSA);
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if (likely(eth_proto_is_802_3(eth->h_proto)))
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return eth->h_proto;
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/*
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* This is a magic hack to spot IPX packets. Older Novell breaks
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* the protocol design and runs IPX over 802.3 without an 802.2 LLC
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* layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
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* won't work for fault tolerant netware but does for the rest.
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*/
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sap = skb_header_pointer(skb, 0, sizeof(*sap), &_service_access_point);
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if (sap && *sap == 0xFFFF)
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return htons(ETH_P_802_3);
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/*
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* Real 802.2 LLC
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*/
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return htons(ETH_P_802_2);
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}
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EXPORT_SYMBOL(eth_type_trans);
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/**
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* eth_header_parse - extract hardware address from packet
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* @skb: packet to extract header from
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* @haddr: destination buffer
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*/
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int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr)
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{
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const struct ethhdr *eth = eth_hdr(skb);
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memcpy(haddr, eth->h_source, ETH_ALEN);
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return ETH_ALEN;
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}
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EXPORT_SYMBOL(eth_header_parse);
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/**
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* eth_header_cache - fill cache entry from neighbour
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* @neigh: source neighbour
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* @hh: destination cache entry
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* @type: Ethernet type field
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*
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* Create an Ethernet header template from the neighbour.
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*/
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int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type)
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{
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struct ethhdr *eth;
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const struct net_device *dev = neigh->dev;
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eth = (struct ethhdr *)
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(((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth))));
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if (type == htons(ETH_P_802_3))
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return -1;
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eth->h_proto = type;
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memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
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memcpy(eth->h_dest, neigh->ha, ETH_ALEN);
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hh->hh_len = ETH_HLEN;
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return 0;
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}
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EXPORT_SYMBOL(eth_header_cache);
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/**
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* eth_header_cache_update - update cache entry
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* @hh: destination cache entry
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* @dev: network device
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* @haddr: new hardware address
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*
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* Called by Address Resolution module to notify changes in address.
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*/
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void eth_header_cache_update(struct hh_cache *hh,
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const struct net_device *dev,
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const unsigned char *haddr)
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{
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memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)),
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haddr, ETH_ALEN);
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}
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EXPORT_SYMBOL(eth_header_cache_update);
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/**
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* eth_prepare_mac_addr_change - prepare for mac change
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* @dev: network device
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* @p: socket address
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*/
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int eth_prepare_mac_addr_change(struct net_device *dev, void *p)
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{
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struct sockaddr *addr = p;
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if (!(dev->priv_flags & IFF_LIVE_ADDR_CHANGE) && netif_running(dev))
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return -EBUSY;
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if (!is_valid_ether_addr(addr->sa_data))
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return -EADDRNOTAVAIL;
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return 0;
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}
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EXPORT_SYMBOL(eth_prepare_mac_addr_change);
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/**
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* eth_commit_mac_addr_change - commit mac change
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* @dev: network device
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* @p: socket address
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*/
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void eth_commit_mac_addr_change(struct net_device *dev, void *p)
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{
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struct sockaddr *addr = p;
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memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
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}
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EXPORT_SYMBOL(eth_commit_mac_addr_change);
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/**
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* eth_mac_addr - set new Ethernet hardware address
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* @dev: network device
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* @p: socket address
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*
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* Change hardware address of device.
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*
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* This doesn't change hardware matching, so needs to be overridden
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* for most real devices.
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*/
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int eth_mac_addr(struct net_device *dev, void *p)
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{
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int ret;
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ret = eth_prepare_mac_addr_change(dev, p);
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if (ret < 0)
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return ret;
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eth_commit_mac_addr_change(dev, p);
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return 0;
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}
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EXPORT_SYMBOL(eth_mac_addr);
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/**
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* eth_change_mtu - set new MTU size
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* @dev: network device
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* @new_mtu: new Maximum Transfer Unit
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*
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* Allow changing MTU size. Needs to be overridden for devices
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* supporting jumbo frames.
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*/
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int eth_change_mtu(struct net_device *dev, int new_mtu)
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{
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netdev_warn(dev, "%s is deprecated\n", __func__);
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dev->mtu = new_mtu;
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return 0;
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}
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EXPORT_SYMBOL(eth_change_mtu);
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int eth_validate_addr(struct net_device *dev)
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{
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if (!is_valid_ether_addr(dev->dev_addr))
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return -EADDRNOTAVAIL;
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return 0;
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}
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EXPORT_SYMBOL(eth_validate_addr);
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const struct header_ops eth_header_ops ____cacheline_aligned = {
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.create = eth_header,
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.parse = eth_header_parse,
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.cache = eth_header_cache,
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.cache_update = eth_header_cache_update,
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};
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/**
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* ether_setup - setup Ethernet network device
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* @dev: network device
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*
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* Fill in the fields of the device structure with Ethernet-generic values.
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*/
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void ether_setup(struct net_device *dev)
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{
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dev->header_ops = ð_header_ops;
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dev->type = ARPHRD_ETHER;
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dev->hard_header_len = ETH_HLEN;
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dev->min_header_len = ETH_HLEN;
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dev->mtu = ETH_DATA_LEN;
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dev->min_mtu = ETH_MIN_MTU;
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dev->max_mtu = ETH_DATA_LEN;
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dev->addr_len = ETH_ALEN;
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dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
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dev->flags = IFF_BROADCAST|IFF_MULTICAST;
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dev->priv_flags |= IFF_TX_SKB_SHARING;
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eth_broadcast_addr(dev->broadcast);
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}
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EXPORT_SYMBOL(ether_setup);
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/**
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* alloc_etherdev_mqs - Allocates and sets up an Ethernet device
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* @sizeof_priv: Size of additional driver-private structure to be allocated
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* for this Ethernet device
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* @txqs: The number of TX queues this device has.
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* @rxqs: The number of RX queues this device has.
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*
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* Fill in the fields of the device structure with Ethernet-generic
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* values. Basically does everything except registering the device.
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*
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* Constructs a new net device, complete with a private data area of
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* size (sizeof_priv). A 32-byte (not bit) alignment is enforced for
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* this private data area.
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*/
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struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
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unsigned int rxqs)
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{
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return alloc_netdev_mqs(sizeof_priv, "eth%d", NET_NAME_UNKNOWN,
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ether_setup, txqs, rxqs);
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}
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EXPORT_SYMBOL(alloc_etherdev_mqs);
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static void devm_free_netdev(struct device *dev, void *res)
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{
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free_netdev(*(struct net_device **)res);
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}
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struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv,
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unsigned int txqs, unsigned int rxqs)
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{
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struct net_device **dr;
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struct net_device *netdev;
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dr = devres_alloc(devm_free_netdev, sizeof(*dr), GFP_KERNEL);
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if (!dr)
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return NULL;
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netdev = alloc_etherdev_mqs(sizeof_priv, txqs, rxqs);
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if (!netdev) {
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devres_free(dr);
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return NULL;
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}
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*dr = netdev;
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devres_add(dev, dr);
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return netdev;
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}
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EXPORT_SYMBOL(devm_alloc_etherdev_mqs);
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ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len)
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{
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return scnprintf(buf, PAGE_SIZE, "%*phC\n", len, addr);
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}
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EXPORT_SYMBOL(sysfs_format_mac);
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struct sk_buff **eth_gro_receive(struct sk_buff **head,
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struct sk_buff *skb)
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{
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struct sk_buff *p, **pp = NULL;
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struct ethhdr *eh, *eh2;
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unsigned int hlen, off_eth;
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const struct packet_offload *ptype;
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__be16 type;
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int flush = 1;
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off_eth = skb_gro_offset(skb);
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hlen = off_eth + sizeof(*eh);
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eh = skb_gro_header_fast(skb, off_eth);
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if (skb_gro_header_hard(skb, hlen)) {
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eh = skb_gro_header_slow(skb, hlen, off_eth);
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if (unlikely(!eh))
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goto out;
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}
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flush = 0;
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for (p = *head; p; p = p->next) {
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if (!NAPI_GRO_CB(p)->same_flow)
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continue;
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eh2 = (struct ethhdr *)(p->data + off_eth);
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if (compare_ether_header(eh, eh2)) {
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NAPI_GRO_CB(p)->same_flow = 0;
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continue;
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}
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}
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type = eh->h_proto;
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rcu_read_lock();
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ptype = gro_find_receive_by_type(type);
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if (ptype == NULL) {
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flush = 1;
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goto out_unlock;
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}
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skb_gro_pull(skb, sizeof(*eh));
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skb_gro_postpull_rcsum(skb, eh, sizeof(*eh));
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pp = call_gro_receive(ptype->callbacks.gro_receive, head, skb);
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out_unlock:
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rcu_read_unlock();
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out:
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skb_gro_flush_final(skb, pp, flush);
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return pp;
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}
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EXPORT_SYMBOL(eth_gro_receive);
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int eth_gro_complete(struct sk_buff *skb, int nhoff)
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{
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struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff);
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__be16 type = eh->h_proto;
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struct packet_offload *ptype;
|
|
int err = -ENOSYS;
|
|
|
|
if (skb->encapsulation)
|
|
skb_set_inner_mac_header(skb, nhoff);
|
|
|
|
rcu_read_lock();
|
|
ptype = gro_find_complete_by_type(type);
|
|
if (ptype != NULL)
|
|
err = ptype->callbacks.gro_complete(skb, nhoff +
|
|
sizeof(struct ethhdr));
|
|
|
|
rcu_read_unlock();
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(eth_gro_complete);
|
|
|
|
static struct packet_offload eth_packet_offload __read_mostly = {
|
|
.type = cpu_to_be16(ETH_P_TEB),
|
|
.priority = 10,
|
|
.callbacks = {
|
|
.gro_receive = eth_gro_receive,
|
|
.gro_complete = eth_gro_complete,
|
|
},
|
|
};
|
|
|
|
static int __init eth_offload_init(void)
|
|
{
|
|
dev_add_offload(ð_packet_offload);
|
|
|
|
return 0;
|
|
}
|
|
|
|
fs_initcall(eth_offload_init);
|
|
|
|
unsigned char * __weak arch_get_platform_mac_address(void)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr)
|
|
{
|
|
const unsigned char *addr;
|
|
struct device_node *dp;
|
|
|
|
if (dev_is_pci(dev))
|
|
dp = pci_device_to_OF_node(to_pci_dev(dev));
|
|
else
|
|
dp = dev->of_node;
|
|
|
|
addr = NULL;
|
|
if (dp)
|
|
addr = of_get_mac_address(dp);
|
|
if (!addr)
|
|
addr = arch_get_platform_mac_address();
|
|
|
|
if (!addr)
|
|
return -ENODEV;
|
|
|
|
ether_addr_copy(mac_addr, addr);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(eth_platform_get_mac_address);
|