linux/drivers/net/arcnet/rfc1201.c

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/*
* Linux ARCnet driver - RFC1201 (standard) packet encapsulation
*
* Written 1994-1999 by Avery Pennarun.
* Derived from skeleton.c by Donald Becker.
*
* Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
* for sponsoring the further development of this driver.
*
* **********************
*
* 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 cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/gfp.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/if_arp.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include "arcdevice.h"
MODULE_LICENSE("GPL");
static __be16 type_trans(struct sk_buff *skb, struct net_device *dev);
static void rx(struct net_device *dev, int bufnum,
struct archdr *pkthdr, int length);
static int build_header(struct sk_buff *skb, struct net_device *dev,
unsigned short type, uint8_t daddr);
static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
int bufnum);
static int continue_tx(struct net_device *dev, int bufnum);
static struct ArcProto rfc1201_proto = {
.suffix = 'a',
.mtu = 1500, /* could be more, but some receivers can't handle it... */
.is_ip = 1, /* This is for sending IP and ARP packages */
.rx = rx,
.build_header = build_header,
.prepare_tx = prepare_tx,
.continue_tx = continue_tx,
.ack_tx = NULL
};
static int __init arcnet_rfc1201_init(void)
{
pr_info("%s\n", "RFC1201 \"standard\" (`a') encapsulation support loaded");
arc_proto_map[ARC_P_IP]
= arc_proto_map[ARC_P_IPV6]
= arc_proto_map[ARC_P_ARP]
= arc_proto_map[ARC_P_RARP]
= arc_proto_map[ARC_P_IPX]
= arc_proto_map[ARC_P_NOVELL_EC]
= &rfc1201_proto;
/* if someone else already owns the broadcast, we won't take it */
if (arc_bcast_proto == arc_proto_default)
arc_bcast_proto = &rfc1201_proto;
return 0;
}
static void __exit arcnet_rfc1201_exit(void)
{
arcnet_unregister_proto(&rfc1201_proto);
}
module_init(arcnet_rfc1201_init);
module_exit(arcnet_rfc1201_exit);
/* Determine a packet's protocol ID.
*
* With ARCnet we have to convert everything to Ethernet-style stuff.
*/
static __be16 type_trans(struct sk_buff *skb, struct net_device *dev)
{
struct archdr *pkt = (struct archdr *)skb->data;
struct arc_rfc1201 *soft = &pkt->soft.rfc1201;
int hdr_size = ARC_HDR_SIZE + RFC1201_HDR_SIZE;
/* Pull off the arcnet header. */
skb_reset_mac_header(skb);
skb_pull(skb, hdr_size);
if (pkt->hard.dest == 0) {
skb->pkt_type = PACKET_BROADCAST;
} else if (dev->flags & IFF_PROMISC) {
/* if we're not sending to ourselves :) */
if (pkt->hard.dest != dev->dev_addr[0])
skb->pkt_type = PACKET_OTHERHOST;
}
/* now return the protocol number */
switch (soft->proto) {
case ARC_P_IP:
return htons(ETH_P_IP);
case ARC_P_IPV6:
return htons(ETH_P_IPV6);
case ARC_P_ARP:
return htons(ETH_P_ARP);
case ARC_P_RARP:
return htons(ETH_P_RARP);
case ARC_P_IPX:
case ARC_P_NOVELL_EC:
return htons(ETH_P_802_3);
default:
dev->stats.rx_errors++;
dev->stats.rx_crc_errors++;
return 0;
}
return htons(ETH_P_IP);
}
/* 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;
struct arc_rfc1201 *soft = &pkthdr->soft.rfc1201;
int saddr = pkt->hard.source, ofs;
struct Incoming *in = &lp->rfc1201.incoming[saddr];
arc_printk(D_DURING, dev, "it's an RFC1201 packet (length=%d)\n",
length);
if (length >= MinTU)
ofs = 512 - length;
else
ofs = 256 - length;
if (soft->split_flag == 0xFF) { /* Exception Packet */
if (length >= 4 + RFC1201_HDR_SIZE) {
arc_printk(D_DURING, dev, "compensating for exception packet\n");
} else {
arc_printk(D_EXTRA, dev, "short RFC1201 exception packet from %02Xh",
saddr);
return;
}
/* skip over 4-byte junkola */
length -= 4;
ofs += 4;
lp->hw.copy_from_card(dev, bufnum, 512 - length,
soft, sizeof(pkt->soft));
}
if (!soft->split_flag) { /* not split */
arc_printk(D_RX, dev, "incoming is not split (splitflag=%d)\n",
soft->split_flag);
if (in->skb) { /* already assembling one! */
arc_printk(D_EXTRA, dev, "aborting assembly (seq=%d) for unsplit packet (splitflag=%d, seq=%d)\n",
in->sequence, soft->split_flag,
soft->sequence);
lp->rfc1201.aborted_seq = soft->sequence;
dev_kfree_skb_irq(in->skb);
dev->stats.rx_errors++;
dev->stats.rx_missed_errors++;
in->skb = NULL;
}
in->sequence = soft->sequence;
skb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC);
if (!skb) {
dev->stats.rx_dropped++;
return;
}
skb_put(skb, length + ARC_HDR_SIZE);
skb->dev = dev;
pkt = (struct archdr *)skb->data;
soft = &pkt->soft.rfc1201;
/* up to sizeof(pkt->soft) has already
* been copied from the card
*/
memcpy(pkt, pkthdr, sizeof(struct archdr));
if (length > sizeof(pkt->soft))
lp->hw.copy_from_card(dev, bufnum,
ofs + sizeof(pkt->soft),
pkt->soft.raw + sizeof(pkt->soft),
length - sizeof(pkt->soft));
/* ARP packets have problems when sent from some DOS systems:
* the source address is always 0!
* So we take the hardware source addr (which is impossible
* to fumble) and insert it ourselves.
*/
if (soft->proto == ARC_P_ARP) {
struct arphdr *arp = (struct arphdr *)soft->payload;
/* make sure addresses are the right length */
if (arp->ar_hln == 1 && arp->ar_pln == 4) {
uint8_t *cptr = (uint8_t *)arp + sizeof(struct arphdr);
if (!*cptr) { /* is saddr = 00? */
arc_printk(D_EXTRA, dev,
"ARP source address was 00h, set to %02Xh\n",
saddr);
dev->stats.rx_crc_errors++;
*cptr = saddr;
} else {
arc_printk(D_DURING, dev, "ARP source address (%Xh) is fine.\n",
*cptr);
}
} else {
arc_printk(D_NORMAL, dev, "funny-shaped ARP packet. (%Xh, %Xh)\n",
arp->ar_hln, arp->ar_pln);
dev->stats.rx_errors++;
dev->stats.rx_crc_errors++;
}
}
if (BUGLVL(D_SKB))
arcnet_dump_skb(dev, skb, "rx");
skb->protocol = type_trans(skb, dev);
netif_rx(skb);
} else { /* split packet */
/* NOTE: MSDOS ARP packet correction should only need to
* apply to unsplit packets, since ARP packets are so short.
*
* My interpretation of the RFC1201 document is that if a
* packet is received out of order, the entire assembly
* process should be aborted.
*
* The RFC also mentions "it is possible for successfully
* received packets to be retransmitted." As of 0.40 all
* previously received packets are allowed, not just the
* most recent one.
*
* We allow multiple assembly processes, one for each
* ARCnet card possible on the network.
* Seems rather like a waste of memory, but there's no
* other way to be reliable.
*/
arc_printk(D_RX, dev, "packet is split (splitflag=%d, seq=%d)\n",
soft->split_flag, in->sequence);
if (in->skb && in->sequence != soft->sequence) {
arc_printk(D_EXTRA, dev, "wrong seq number (saddr=%d, expected=%d, seq=%d, splitflag=%d)\n",
saddr, in->sequence, soft->sequence,
soft->split_flag);
dev_kfree_skb_irq(in->skb);
in->skb = NULL;
dev->stats.rx_errors++;
dev->stats.rx_missed_errors++;
in->lastpacket = in->numpackets = 0;
}
if (soft->split_flag & 1) { /* first packet in split */
arc_printk(D_RX, dev, "brand new splitpacket (splitflag=%d)\n",
soft->split_flag);
if (in->skb) { /* already assembling one! */
arc_printk(D_EXTRA, dev, "aborting previous (seq=%d) assembly (splitflag=%d, seq=%d)\n",
in->sequence, soft->split_flag,
soft->sequence);
dev->stats.rx_errors++;
dev->stats.rx_missed_errors++;
dev_kfree_skb_irq(in->skb);
}
in->sequence = soft->sequence;
in->numpackets = ((unsigned)soft->split_flag >> 1) + 2;
in->lastpacket = 1;
if (in->numpackets > 16) {
arc_printk(D_EXTRA, dev, "incoming packet more than 16 segments; dropping. (splitflag=%d)\n",
soft->split_flag);
lp->rfc1201.aborted_seq = soft->sequence;
dev->stats.rx_errors++;
dev->stats.rx_length_errors++;
return;
}
in->skb = skb = alloc_skb(508 * in->numpackets + ARC_HDR_SIZE,
GFP_ATOMIC);
if (!skb) {
arc_printk(D_NORMAL, dev, "(split) memory squeeze, dropping packet.\n");
lp->rfc1201.aborted_seq = soft->sequence;
dev->stats.rx_dropped++;
return;
}
skb->dev = dev;
pkt = (struct archdr *)skb->data;
soft = &pkt->soft.rfc1201;
memcpy(pkt, pkthdr, ARC_HDR_SIZE + RFC1201_HDR_SIZE);
skb_put(skb, ARC_HDR_SIZE + RFC1201_HDR_SIZE);
soft->split_flag = 0; /* end result won't be split */
} else { /* not first packet */
int packetnum = ((unsigned)soft->split_flag >> 1) + 1;
/* if we're not assembling, there's no point trying to
* continue.
*/
if (!in->skb) {
if (lp->rfc1201.aborted_seq != soft->sequence) {
arc_printk(D_EXTRA, dev, "can't continue split without starting first! (splitflag=%d, seq=%d, aborted=%d)\n",
soft->split_flag,
soft->sequence,
lp->rfc1201.aborted_seq);
dev->stats.rx_errors++;
dev->stats.rx_missed_errors++;
}
return;
}
in->lastpacket++;
/* if not the right flag */
if (packetnum != in->lastpacket) {
/* harmless duplicate? ignore. */
if (packetnum <= in->lastpacket - 1) {
arc_printk(D_EXTRA, dev, "duplicate splitpacket ignored! (splitflag=%d)\n",
soft->split_flag);
dev->stats.rx_errors++;
dev->stats.rx_frame_errors++;
return;
}
/* "bad" duplicate, kill reassembly */
arc_printk(D_EXTRA, dev, "out-of-order splitpacket, reassembly (seq=%d) aborted (splitflag=%d, seq=%d)\n",
in->sequence, soft->split_flag,
soft->sequence);
lp->rfc1201.aborted_seq = soft->sequence;
dev_kfree_skb_irq(in->skb);
in->skb = NULL;
dev->stats.rx_errors++;
dev->stats.rx_missed_errors++;
in->lastpacket = in->numpackets = 0;
return;
}
pkt = (struct archdr *)in->skb->data;
soft = &pkt->soft.rfc1201;
}
skb = in->skb;
lp->hw.copy_from_card(dev, bufnum, ofs + RFC1201_HDR_SIZE,
skb->data + skb->len,
length - RFC1201_HDR_SIZE);
skb_put(skb, length - RFC1201_HDR_SIZE);
/* are we done? */
if (in->lastpacket == in->numpackets) {
in->skb = NULL;
in->lastpacket = in->numpackets = 0;
arc_printk(D_SKB_SIZE, dev, "skb: received %d bytes from %02X (unsplit)\n",
skb->len, pkt->hard.source);
arc_printk(D_SKB_SIZE, dev, "skb: received %d bytes from %02X (split)\n",
skb->len, pkt->hard.source);
if (BUGLVL(D_SKB))
arcnet_dump_skb(dev, skb, "rx");
skb->protocol = type_trans(skb, dev);
netif_rx(skb);
}
}
}
/* Create the ARCnet hard/soft headers for RFC1201. */
static int build_header(struct sk_buff *skb, struct net_device *dev,
unsigned short type, uint8_t daddr)
{
struct arcnet_local *lp = netdev_priv(dev);
int hdr_size = ARC_HDR_SIZE + RFC1201_HDR_SIZE;
struct archdr *pkt = (struct archdr *)skb_push(skb, hdr_size);
struct arc_rfc1201 *soft = &pkt->soft.rfc1201;
/* set the protocol ID according to RFC1201 */
switch (type) {
case ETH_P_IP:
soft->proto = ARC_P_IP;
break;
case ETH_P_IPV6:
soft->proto = ARC_P_IPV6;
break;
case ETH_P_ARP:
soft->proto = ARC_P_ARP;
break;
case ETH_P_RARP:
soft->proto = ARC_P_RARP;
break;
case ETH_P_IPX:
case ETH_P_802_3:
case ETH_P_802_2:
soft->proto = ARC_P_IPX;
break;
case ETH_P_ATALK:
soft->proto = ARC_P_ATALK;
break;
default:
arc_printk(D_NORMAL, dev, "RFC1201: I don't understand protocol %d (%Xh)\n",
type, type);
dev->stats.tx_errors++;
dev->stats.tx_aborted_errors++;
return 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;
soft->sequence = htons(lp->rfc1201.sequence++);
soft->split_flag = 0; /* split packets are done elsewhere */
/* 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.
* For now, always broadcasting will probably at least get
* packets sent out :)
*/
pkt->hard.dest = 0;
return hdr_size;
}
/* otherwise, drop in the dest address */
pkt->hard.dest = daddr;
return hdr_size;
}
static void load_pkt(struct net_device *dev, struct arc_hardware *hard,
struct arc_rfc1201 *soft, int softlen, int bufnum)
{
struct arcnet_local *lp = netdev_priv(dev);
int ofs;
/* assume length <= XMTU: someone should have handled that by now. */
if (softlen > MinTU) {
hard->offset[0] = 0;
hard->offset[1] = ofs = 512 - softlen;
} else if (softlen > MTU) { /* exception packet - add an extra header */
struct arc_rfc1201 excsoft;
excsoft.proto = soft->proto;
excsoft.split_flag = 0xff;
excsoft.sequence = htons(0xffff);
hard->offset[0] = 0;
ofs = 512 - softlen;
hard->offset[1] = ofs - RFC1201_HDR_SIZE;
lp->hw.copy_to_card(dev, bufnum, ofs - RFC1201_HDR_SIZE,
&excsoft, RFC1201_HDR_SIZE);
} else {
hard->offset[0] = ofs = 256 - softlen;
}
lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
lp->hw.copy_to_card(dev, bufnum, ofs, soft, softlen);
lp->lastload_dest = hard->dest;
}
static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
int bufnum)
{
struct arcnet_local *lp = netdev_priv(dev);
const int maxsegsize = XMTU - RFC1201_HDR_SIZE;
struct Outgoing *out;
arc_printk(D_DURING, dev, "prepare_tx: txbufs=%d/%d/%d\n",
lp->next_tx, lp->cur_tx, bufnum);
/* hard header is not included in packet length */
length -= ARC_HDR_SIZE;
pkt->soft.rfc1201.split_flag = 0;
/* need to do a split packet? */
if (length > XMTU) {
out = &lp->outgoing;
out->length = length - RFC1201_HDR_SIZE;
out->dataleft = lp->outgoing.length;
out->numsegs = (out->dataleft + maxsegsize - 1) / maxsegsize;
out->segnum = 0;
arc_printk(D_DURING, dev, "rfc1201 prep_tx: ready for %d-segment split (%d bytes, seq=%d)\n",
out->numsegs, out->length,
pkt->soft.rfc1201.sequence);
return 0; /* not done */
}
/* just load the packet into the buffers and send it off */
load_pkt(dev, &pkt->hard, &pkt->soft.rfc1201, length, bufnum);
return 1; /* done */
}
static int continue_tx(struct net_device *dev, int bufnum)
{
struct arcnet_local *lp = netdev_priv(dev);
struct Outgoing *out = &lp->outgoing;
struct arc_hardware *hard = &out->pkt->hard;
struct arc_rfc1201 *soft = &out->pkt->soft.rfc1201, *newsoft;
int maxsegsize = XMTU - RFC1201_HDR_SIZE;
int seglen;
arc_printk(D_DURING, dev,
"rfc1201 continue_tx: loading segment %d(+1) of %d (seq=%d)\n",
out->segnum, out->numsegs, soft->sequence);
/* the "new" soft header comes right before the data chunk */
newsoft = (struct arc_rfc1201 *)
(out->pkt->soft.raw + out->length - out->dataleft);
if (!out->segnum) /* first packet; newsoft == soft */
newsoft->split_flag = ((out->numsegs - 2) << 1) | 1;
else {
newsoft->split_flag = out->segnum << 1;
newsoft->proto = soft->proto;
newsoft->sequence = soft->sequence;
}
seglen = maxsegsize;
if (seglen > out->dataleft)
seglen = out->dataleft;
out->dataleft -= seglen;
load_pkt(dev, hard, newsoft, seglen + RFC1201_HDR_SIZE, bufnum);
out->segnum++;
if (out->segnum >= out->numsegs)
return 1;
else
return 0;
}