linux/drivers/net/cxgb4/l2t.c
stephen hemminger 31b9c19bfe cxgb4: function namespace cleanup (v3)
Make functions only used in one file local.
Remove lots of dead code, relating to unsupported functions
in mainline driver like RSS, IPv6, and TCP offload.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-21 04:25:49 -07:00

598 lines
15 KiB
C

/*
* This file is part of the Chelsio T4 Ethernet driver for Linux.
*
* Copyright (c) 2003-2010 Chelsio Communications, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if.h>
#include <linux/if_vlan.h>
#include <linux/jhash.h>
#include <net/neighbour.h>
#include "cxgb4.h"
#include "l2t.h"
#include "t4_msg.h"
#include "t4fw_api.h"
#define VLAN_NONE 0xfff
/* identifies sync vs async L2T_WRITE_REQs */
#define F_SYNC_WR (1 << 12)
enum {
L2T_STATE_VALID, /* entry is up to date */
L2T_STATE_STALE, /* entry may be used but needs revalidation */
L2T_STATE_RESOLVING, /* entry needs address resolution */
L2T_STATE_SYNC_WRITE, /* synchronous write of entry underway */
/* when state is one of the below the entry is not hashed */
L2T_STATE_SWITCHING, /* entry is being used by a switching filter */
L2T_STATE_UNUSED /* entry not in use */
};
struct l2t_data {
rwlock_t lock;
atomic_t nfree; /* number of free entries */
struct l2t_entry *rover; /* starting point for next allocation */
struct l2t_entry l2tab[L2T_SIZE];
};
static inline unsigned int vlan_prio(const struct l2t_entry *e)
{
return e->vlan >> 13;
}
static inline void l2t_hold(struct l2t_data *d, struct l2t_entry *e)
{
if (atomic_add_return(1, &e->refcnt) == 1) /* 0 -> 1 transition */
atomic_dec(&d->nfree);
}
/*
* To avoid having to check address families we do not allow v4 and v6
* neighbors to be on the same hash chain. We keep v4 entries in the first
* half of available hash buckets and v6 in the second.
*/
enum {
L2T_SZ_HALF = L2T_SIZE / 2,
L2T_HASH_MASK = L2T_SZ_HALF - 1
};
static inline unsigned int arp_hash(const u32 *key, int ifindex)
{
return jhash_2words(*key, ifindex, 0) & L2T_HASH_MASK;
}
static inline unsigned int ipv6_hash(const u32 *key, int ifindex)
{
u32 xor = key[0] ^ key[1] ^ key[2] ^ key[3];
return L2T_SZ_HALF + (jhash_2words(xor, ifindex, 0) & L2T_HASH_MASK);
}
static unsigned int addr_hash(const u32 *addr, int addr_len, int ifindex)
{
return addr_len == 4 ? arp_hash(addr, ifindex) :
ipv6_hash(addr, ifindex);
}
/*
* Checks if an L2T entry is for the given IP/IPv6 address. It does not check
* whether the L2T entry and the address are of the same address family.
* Callers ensure an address is only checked against L2T entries of the same
* family, something made trivial by the separation of IP and IPv6 hash chains
* mentioned above. Returns 0 if there's a match,
*/
static int addreq(const struct l2t_entry *e, const u32 *addr)
{
if (e->v6)
return (e->addr[0] ^ addr[0]) | (e->addr[1] ^ addr[1]) |
(e->addr[2] ^ addr[2]) | (e->addr[3] ^ addr[3]);
return e->addr[0] ^ addr[0];
}
static void neigh_replace(struct l2t_entry *e, struct neighbour *n)
{
neigh_hold(n);
if (e->neigh)
neigh_release(e->neigh);
e->neigh = n;
}
/*
* Write an L2T entry. Must be called with the entry locked.
* The write may be synchronous or asynchronous.
*/
static int write_l2e(struct adapter *adap, struct l2t_entry *e, int sync)
{
struct sk_buff *skb;
struct cpl_l2t_write_req *req;
skb = alloc_skb(sizeof(*req), GFP_ATOMIC);
if (!skb)
return -ENOMEM;
req = (struct cpl_l2t_write_req *)__skb_put(skb, sizeof(*req));
INIT_TP_WR(req, 0);
OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ,
e->idx | (sync ? F_SYNC_WR : 0) |
TID_QID(adap->sge.fw_evtq.abs_id)));
req->params = htons(L2T_W_PORT(e->lport) | L2T_W_NOREPLY(!sync));
req->l2t_idx = htons(e->idx);
req->vlan = htons(e->vlan);
if (e->neigh)
memcpy(e->dmac, e->neigh->ha, sizeof(e->dmac));
memcpy(req->dst_mac, e->dmac, sizeof(req->dst_mac));
set_wr_txq(skb, CPL_PRIORITY_CONTROL, 0);
t4_ofld_send(adap, skb);
if (sync && e->state != L2T_STATE_SWITCHING)
e->state = L2T_STATE_SYNC_WRITE;
return 0;
}
/*
* Send packets waiting in an L2T entry's ARP queue. Must be called with the
* entry locked.
*/
static void send_pending(struct adapter *adap, struct l2t_entry *e)
{
while (e->arpq_head) {
struct sk_buff *skb = e->arpq_head;
e->arpq_head = skb->next;
skb->next = NULL;
t4_ofld_send(adap, skb);
}
e->arpq_tail = NULL;
}
/*
* Process a CPL_L2T_WRITE_RPL. Wake up the ARP queue if it completes a
* synchronous L2T_WRITE. Note that the TID in the reply is really the L2T
* index it refers to.
*/
void do_l2t_write_rpl(struct adapter *adap, const struct cpl_l2t_write_rpl *rpl)
{
unsigned int tid = GET_TID(rpl);
unsigned int idx = tid & (L2T_SIZE - 1);
if (unlikely(rpl->status != CPL_ERR_NONE)) {
dev_err(adap->pdev_dev,
"Unexpected L2T_WRITE_RPL status %u for entry %u\n",
rpl->status, idx);
return;
}
if (tid & F_SYNC_WR) {
struct l2t_entry *e = &adap->l2t->l2tab[idx];
spin_lock(&e->lock);
if (e->state != L2T_STATE_SWITCHING) {
send_pending(adap, e);
e->state = (e->neigh->nud_state & NUD_STALE) ?
L2T_STATE_STALE : L2T_STATE_VALID;
}
spin_unlock(&e->lock);
}
}
/*
* Add a packet to an L2T entry's queue of packets awaiting resolution.
* Must be called with the entry's lock held.
*/
static inline void arpq_enqueue(struct l2t_entry *e, struct sk_buff *skb)
{
skb->next = NULL;
if (e->arpq_head)
e->arpq_tail->next = skb;
else
e->arpq_head = skb;
e->arpq_tail = skb;
}
int cxgb4_l2t_send(struct net_device *dev, struct sk_buff *skb,
struct l2t_entry *e)
{
struct adapter *adap = netdev2adap(dev);
again:
switch (e->state) {
case L2T_STATE_STALE: /* entry is stale, kick off revalidation */
neigh_event_send(e->neigh, NULL);
spin_lock_bh(&e->lock);
if (e->state == L2T_STATE_STALE)
e->state = L2T_STATE_VALID;
spin_unlock_bh(&e->lock);
case L2T_STATE_VALID: /* fast-path, send the packet on */
return t4_ofld_send(adap, skb);
case L2T_STATE_RESOLVING:
case L2T_STATE_SYNC_WRITE:
spin_lock_bh(&e->lock);
if (e->state != L2T_STATE_SYNC_WRITE &&
e->state != L2T_STATE_RESOLVING) {
spin_unlock_bh(&e->lock);
goto again;
}
arpq_enqueue(e, skb);
spin_unlock_bh(&e->lock);
if (e->state == L2T_STATE_RESOLVING &&
!neigh_event_send(e->neigh, NULL)) {
spin_lock_bh(&e->lock);
if (e->state == L2T_STATE_RESOLVING && e->arpq_head)
write_l2e(adap, e, 1);
spin_unlock_bh(&e->lock);
}
}
return 0;
}
EXPORT_SYMBOL(cxgb4_l2t_send);
/*
* Allocate a free L2T entry. Must be called with l2t_data.lock held.
*/
static struct l2t_entry *alloc_l2e(struct l2t_data *d)
{
struct l2t_entry *end, *e, **p;
if (!atomic_read(&d->nfree))
return NULL;
/* there's definitely a free entry */
for (e = d->rover, end = &d->l2tab[L2T_SIZE]; e != end; ++e)
if (atomic_read(&e->refcnt) == 0)
goto found;
for (e = d->l2tab; atomic_read(&e->refcnt); ++e)
;
found:
d->rover = e + 1;
atomic_dec(&d->nfree);
/*
* The entry we found may be an inactive entry that is
* presently in the hash table. We need to remove it.
*/
if (e->state < L2T_STATE_SWITCHING)
for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next)
if (*p == e) {
*p = e->next;
e->next = NULL;
break;
}
e->state = L2T_STATE_UNUSED;
return e;
}
/*
* Called when an L2T entry has no more users.
*/
static void t4_l2e_free(struct l2t_entry *e)
{
struct l2t_data *d;
spin_lock_bh(&e->lock);
if (atomic_read(&e->refcnt) == 0) { /* hasn't been recycled */
if (e->neigh) {
neigh_release(e->neigh);
e->neigh = NULL;
}
while (e->arpq_head) {
struct sk_buff *skb = e->arpq_head;
e->arpq_head = skb->next;
kfree_skb(skb);
}
e->arpq_tail = NULL;
}
spin_unlock_bh(&e->lock);
d = container_of(e, struct l2t_data, l2tab[e->idx]);
atomic_inc(&d->nfree);
}
void cxgb4_l2t_release(struct l2t_entry *e)
{
if (atomic_dec_and_test(&e->refcnt))
t4_l2e_free(e);
}
EXPORT_SYMBOL(cxgb4_l2t_release);
/*
* Update an L2T entry that was previously used for the same next hop as neigh.
* Must be called with softirqs disabled.
*/
static void reuse_entry(struct l2t_entry *e, struct neighbour *neigh)
{
unsigned int nud_state;
spin_lock(&e->lock); /* avoid race with t4_l2t_free */
if (neigh != e->neigh)
neigh_replace(e, neigh);
nud_state = neigh->nud_state;
if (memcmp(e->dmac, neigh->ha, sizeof(e->dmac)) ||
!(nud_state & NUD_VALID))
e->state = L2T_STATE_RESOLVING;
else if (nud_state & NUD_CONNECTED)
e->state = L2T_STATE_VALID;
else
e->state = L2T_STATE_STALE;
spin_unlock(&e->lock);
}
struct l2t_entry *cxgb4_l2t_get(struct l2t_data *d, struct neighbour *neigh,
const struct net_device *physdev,
unsigned int priority)
{
u8 lport;
u16 vlan;
struct l2t_entry *e;
int addr_len = neigh->tbl->key_len;
u32 *addr = (u32 *)neigh->primary_key;
int ifidx = neigh->dev->ifindex;
int hash = addr_hash(addr, addr_len, ifidx);
if (neigh->dev->flags & IFF_LOOPBACK)
lport = netdev2pinfo(physdev)->tx_chan + 4;
else
lport = netdev2pinfo(physdev)->lport;
if (neigh->dev->priv_flags & IFF_802_1Q_VLAN)
vlan = vlan_dev_vlan_id(neigh->dev);
else
vlan = VLAN_NONE;
write_lock_bh(&d->lock);
for (e = d->l2tab[hash].first; e; e = e->next)
if (!addreq(e, addr) && e->ifindex == ifidx &&
e->vlan == vlan && e->lport == lport) {
l2t_hold(d, e);
if (atomic_read(&e->refcnt) == 1)
reuse_entry(e, neigh);
goto done;
}
/* Need to allocate a new entry */
e = alloc_l2e(d);
if (e) {
spin_lock(&e->lock); /* avoid race with t4_l2t_free */
e->state = L2T_STATE_RESOLVING;
memcpy(e->addr, addr, addr_len);
e->ifindex = ifidx;
e->hash = hash;
e->lport = lport;
e->v6 = addr_len == 16;
atomic_set(&e->refcnt, 1);
neigh_replace(e, neigh);
e->vlan = vlan;
e->next = d->l2tab[hash].first;
d->l2tab[hash].first = e;
spin_unlock(&e->lock);
}
done:
write_unlock_bh(&d->lock);
return e;
}
EXPORT_SYMBOL(cxgb4_l2t_get);
/*
* Called when address resolution fails for an L2T entry to handle packets
* on the arpq head. If a packet specifies a failure handler it is invoked,
* otherwise the packet is sent to the device.
*/
static void handle_failed_resolution(struct adapter *adap, struct sk_buff *arpq)
{
while (arpq) {
struct sk_buff *skb = arpq;
const struct l2t_skb_cb *cb = L2T_SKB_CB(skb);
arpq = skb->next;
skb->next = NULL;
if (cb->arp_err_handler)
cb->arp_err_handler(cb->handle, skb);
else
t4_ofld_send(adap, skb);
}
}
/*
* Called when the host's neighbor layer makes a change to some entry that is
* loaded into the HW L2 table.
*/
void t4_l2t_update(struct adapter *adap, struct neighbour *neigh)
{
struct l2t_entry *e;
struct sk_buff *arpq = NULL;
struct l2t_data *d = adap->l2t;
int addr_len = neigh->tbl->key_len;
u32 *addr = (u32 *) neigh->primary_key;
int ifidx = neigh->dev->ifindex;
int hash = addr_hash(addr, addr_len, ifidx);
read_lock_bh(&d->lock);
for (e = d->l2tab[hash].first; e; e = e->next)
if (!addreq(e, addr) && e->ifindex == ifidx) {
spin_lock(&e->lock);
if (atomic_read(&e->refcnt))
goto found;
spin_unlock(&e->lock);
break;
}
read_unlock_bh(&d->lock);
return;
found:
read_unlock(&d->lock);
if (neigh != e->neigh)
neigh_replace(e, neigh);
if (e->state == L2T_STATE_RESOLVING) {
if (neigh->nud_state & NUD_FAILED) {
arpq = e->arpq_head;
e->arpq_head = e->arpq_tail = NULL;
} else if ((neigh->nud_state & (NUD_CONNECTED | NUD_STALE)) &&
e->arpq_head) {
write_l2e(adap, e, 1);
}
} else {
e->state = neigh->nud_state & NUD_CONNECTED ?
L2T_STATE_VALID : L2T_STATE_STALE;
if (memcmp(e->dmac, neigh->ha, sizeof(e->dmac)))
write_l2e(adap, e, 0);
}
spin_unlock_bh(&e->lock);
if (arpq)
handle_failed_resolution(adap, arpq);
}
struct l2t_data *t4_init_l2t(void)
{
int i;
struct l2t_data *d;
d = t4_alloc_mem(sizeof(*d));
if (!d)
return NULL;
d->rover = d->l2tab;
atomic_set(&d->nfree, L2T_SIZE);
rwlock_init(&d->lock);
for (i = 0; i < L2T_SIZE; ++i) {
d->l2tab[i].idx = i;
d->l2tab[i].state = L2T_STATE_UNUSED;
spin_lock_init(&d->l2tab[i].lock);
atomic_set(&d->l2tab[i].refcnt, 0);
}
return d;
}
#include <linux/module.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
static inline void *l2t_get_idx(struct seq_file *seq, loff_t pos)
{
struct l2t_entry *l2tab = seq->private;
return pos >= L2T_SIZE ? NULL : &l2tab[pos];
}
static void *l2t_seq_start(struct seq_file *seq, loff_t *pos)
{
return *pos ? l2t_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
}
static void *l2t_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
v = l2t_get_idx(seq, *pos);
if (v)
++*pos;
return v;
}
static void l2t_seq_stop(struct seq_file *seq, void *v)
{
}
static char l2e_state(const struct l2t_entry *e)
{
switch (e->state) {
case L2T_STATE_VALID: return 'V';
case L2T_STATE_STALE: return 'S';
case L2T_STATE_SYNC_WRITE: return 'W';
case L2T_STATE_RESOLVING: return e->arpq_head ? 'A' : 'R';
case L2T_STATE_SWITCHING: return 'X';
default:
return 'U';
}
}
static int l2t_seq_show(struct seq_file *seq, void *v)
{
if (v == SEQ_START_TOKEN)
seq_puts(seq, " Idx IP address "
"Ethernet address VLAN/P LP State Users Port\n");
else {
char ip[60];
struct l2t_entry *e = v;
spin_lock_bh(&e->lock);
if (e->state == L2T_STATE_SWITCHING)
ip[0] = '\0';
else
sprintf(ip, e->v6 ? "%pI6c" : "%pI4", e->addr);
seq_printf(seq, "%4u %-25s %17pM %4d %u %2u %c %5u %s\n",
e->idx, ip, e->dmac,
e->vlan & VLAN_VID_MASK, vlan_prio(e), e->lport,
l2e_state(e), atomic_read(&e->refcnt),
e->neigh ? e->neigh->dev->name : "");
spin_unlock_bh(&e->lock);
}
return 0;
}
static const struct seq_operations l2t_seq_ops = {
.start = l2t_seq_start,
.next = l2t_seq_next,
.stop = l2t_seq_stop,
.show = l2t_seq_show
};
static int l2t_seq_open(struct inode *inode, struct file *file)
{
int rc = seq_open(file, &l2t_seq_ops);
if (!rc) {
struct adapter *adap = inode->i_private;
struct seq_file *seq = file->private_data;
seq->private = adap->l2t->l2tab;
}
return rc;
}
const struct file_operations t4_l2t_fops = {
.owner = THIS_MODULE,
.open = l2t_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};