firewire: net: allow for unordered unit discovery

Decouple the creation and destruction of the net_device from the order
of discovery and removal of nodes with RFC 2734 unit directories since
there is no reliable order.  The net_device is now created when the
first RFC 2734 unit on a card is discovered, and destroyed when the last
RFC 2734 unit on a card went away.  This includes all remote units as
well as the local unit, which is therefore tracked as a peer now too.

Also, locking around the list of peers is slightly extended to guard
against peer removal.  As a side effect, fwnet_peer.pdg_lock has become
superfluous and is deleted.

Peer data (max_rec, speed, node ID, generation) are updated more
carefully.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This commit is contained in:
Stefan Richter 2009-06-14 11:45:27 +02:00
parent f91e3bd842
commit 5a124d382e
3 changed files with 216 additions and 262 deletions

View File

@ -429,8 +429,6 @@ void fw_card_initialize(struct fw_card *card,
card->local_node = NULL;
INIT_DELAYED_WORK(&card->work, fw_card_bm_work);
card->netdev = NULL;
INIT_LIST_HEAD(&card->peer_list);
}
EXPORT_SYMBOL(fw_card_initialize);

View File

@ -18,8 +18,10 @@
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <asm/unaligned.h>
#include <net/arp.h>
@ -135,40 +137,11 @@ struct fwnet_partial_datagram {
u16 datagram_size;
};
/*
* We keep one of these for each IPv4 capable device attached to a fw_card.
* The list of them is stored in the fw_card structure rather than in the
* fwnet_device because the remote IPv4 nodes may be probed before the card is,
* so we need a place to store them before the fwnet_device structure is
* allocated.
*/
struct fwnet_peer {
struct list_head peer_link;
/* guid of the remote peer */
u64 guid;
/* FIFO address to transmit datagrams to, or FWNET_NO_FIFO_ADDR */
u64 fifo;
spinlock_t pdg_lock; /* partial datagram lock */
/* List of partial datagrams received from this peer */
struct list_head pd_list;
/* Number of entries in pd_list at the moment */
unsigned pdg_size;
/* max payload to transmit to this remote peer */
/* This already includes the RFC2374_FRAG_HDR_SIZE overhead */
u16 max_payload;
/* outgoing datagram label */
u16 datagram_label;
/* Current node_id of the remote peer */
u16 node_id;
/* current generation of the remote peer */
u8 generation;
/* max speed that this peer can receive at */
u8 xmt_speed;
};
static DEFINE_MUTEX(fwnet_device_mutex);
static LIST_HEAD(fwnet_device_list);
struct fwnet_device {
struct list_head dev_link;
spinlock_t lock;
enum {
FWNET_BROADCAST_ERROR,
@ -206,7 +179,26 @@ struct fwnet_device {
/* List of packets that have been sent but not yet acked */
struct list_head sent_list;
struct list_head peer_list;
struct fw_card *card;
struct net_device *netdev;
};
struct fwnet_peer {
struct list_head peer_link;
struct fwnet_device *dev;
u64 guid;
u64 fifo;
/* guarded by dev->lock */
struct list_head pd_list; /* received partial datagrams */
unsigned pdg_size; /* pd_list size */
u16 datagram_label; /* outgoing datagram label */
unsigned max_payload; /* includes RFC2374_FRAG_HDR_SIZE overhead */
int node_id;
int generation;
unsigned speed;
};
/* This is our task struct. It's used for the packet complete callback. */
@ -479,102 +471,47 @@ static bool fwnet_pd_is_complete(struct fwnet_partial_datagram *pd)
return fi->len == pd->datagram_size;
}
static int fwnet_peer_new(struct fw_card *card, struct fw_device *device)
{
struct fwnet_peer *peer;
peer = kmalloc(sizeof(*peer), GFP_KERNEL);
if (!peer) {
fw_error("out of memory\n");
return -ENOMEM;
}
peer->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
peer->fifo = FWNET_NO_FIFO_ADDR;
INIT_LIST_HEAD(&peer->pd_list);
spin_lock_init(&peer->pdg_lock);
peer->pdg_size = 0;
peer->generation = device->generation;
rmb();
peer->node_id = device->node_id;
/* FIXME what should it really be? */
peer->max_payload = IEEE1394_MAX_PAYLOAD_S100 - RFC2374_UNFRAG_HDR_SIZE;
peer->datagram_label = 0U;
peer->xmt_speed = device->max_speed;
list_add_tail(&peer->peer_link, &card->peer_list);
return 0;
}
/* FIXME caller must take the lock, or peer needs to be reference-counted */
/* caller must hold dev->lock */
static struct fwnet_peer *fwnet_peer_find_by_guid(struct fwnet_device *dev,
u64 guid)
{
struct fwnet_peer *p, *peer = NULL;
unsigned long flags;
spin_lock_irqsave(&dev->lock, flags);
list_for_each_entry(p, &dev->card->peer_list, peer_link)
if (p->guid == guid) {
peer = p;
break;
}
spin_unlock_irqrestore(&dev->lock, flags);
return peer;
}
/* FIXME caller must take the lock, or peer needs to be reference-counted */
/* FIXME node_id doesn't mean anything without generation */
static struct fwnet_peer *fwnet_peer_find_by_node_id(struct fwnet_device *dev,
u16 node_id)
{
struct fwnet_peer *p, *peer = NULL;
unsigned long flags;
spin_lock_irqsave(&dev->lock, flags);
list_for_each_entry(p, &dev->card->peer_list, peer_link)
if (p->node_id == node_id) {
peer = p;
break;
}
spin_unlock_irqrestore(&dev->lock, flags);
return peer;
}
/* FIXME */
static void fwnet_peer_delete(struct fw_card *card, struct fw_device *device)
{
struct net_device *net;
struct fwnet_device *dev;
struct fwnet_peer *peer;
u64 guid;
unsigned long flags;
struct fwnet_partial_datagram *pd, *pd_next;
guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
net = card->netdev;
if (net)
dev = netdev_priv(net);
else
dev = NULL;
if (dev)
spin_lock_irqsave(&dev->lock, flags);
list_for_each_entry(peer, &dev->peer_list, peer_link)
if (peer->guid == guid)
return peer;
list_for_each_entry(peer, &card->peer_list, peer_link) {
if (peer->guid == guid) {
list_del(&peer->peer_link);
list_for_each_entry_safe(pd, pd_next, &peer->pd_list,
pd_link)
fwnet_pd_delete(pd);
break;
}
}
if (dev)
spin_unlock_irqrestore(&dev->lock, flags);
return NULL;
}
/* caller must hold dev->lock */
static struct fwnet_peer *fwnet_peer_find_by_node_id(struct fwnet_device *dev,
int node_id, int generation)
{
struct fwnet_peer *peer;
list_for_each_entry(peer, &dev->peer_list, peer_link)
if (peer->node_id == node_id &&
peer->generation == generation)
return peer;
return NULL;
}
/* See IEEE 1394-2008 table 6-4, table 8-8, table 16-18. */
static unsigned fwnet_max_payload(unsigned max_rec, unsigned speed)
{
max_rec = min(max_rec, speed + 8);
max_rec = min(max_rec, 0xbU); /* <= 4096 */
if (max_rec < 8) {
fw_notify("max_rec %x out of range\n", max_rec);
max_rec = 8;
}
return (1 << (max_rec + 1)) - RFC2374_FRAG_HDR_SIZE;
}
static int fwnet_finish_incoming_packet(struct net_device *net,
struct sk_buff *skb, u16 source_node_id,
bool is_broadcast, u16 ether_type)
@ -606,71 +543,44 @@ static int fwnet_finish_incoming_packet(struct net_device *net,
unsigned char *arp_ptr;
u64 fifo_addr;
u64 peer_guid;
u8 max_rec;
u8 sspd;
unsigned sspd;
u16 max_payload;
struct fwnet_peer *peer;
static const u16 fwnet_speed_to_max_payload[] = {
/* S100, S200, S400, S800, S1600, S3200 */
512, 1024, 2048, 4096, 4096, 4096
};
unsigned long flags;
arp1394 = (struct rfc2734_arp *)skb->data;
arp = (struct arphdr *)skb->data;
arp_ptr = (unsigned char *)(arp + 1);
fifo_addr = (u64)ntohs(arp1394->fifo_hi) << 32
| ntohl(arp1394->fifo_lo);
max_rec = dev->card->max_receive;
if (arp1394->max_rec < max_rec)
max_rec = arp1394->max_rec;
peer_guid = get_unaligned_be64(&arp1394->s_uniq_id);
fifo_addr = (u64)get_unaligned_be16(&arp1394->fifo_hi) << 32
| get_unaligned_be32(&arp1394->fifo_lo);
sspd = arp1394->sspd;
/* Sanity check. OS X 10.3 PPC reportedly sends 131. */
if (sspd > SCODE_3200) {
fw_notify("sspd %x out of range\n", sspd);
sspd = 0;
sspd = SCODE_3200;
}
max_payload = fwnet_max_payload(arp1394->max_rec, sspd);
max_payload = min(fwnet_speed_to_max_payload[sspd],
(u16)(1 << (max_rec + 1))) - RFC2374_UNFRAG_HDR_SIZE;
peer_guid = get_unaligned_be64(&arp1394->s_uniq_id);
spin_lock_irqsave(&dev->lock, flags);
peer = fwnet_peer_find_by_guid(dev, peer_guid);
if (peer) {
peer->fifo = fifo_addr;
if (peer->speed > sspd)
peer->speed = sspd;
if (peer->max_payload > max_payload)
peer->max_payload = max_payload;
}
spin_unlock_irqrestore(&dev->lock, flags);
if (!peer) {
fw_notify("No peer for ARP packet from %016llx\n",
(unsigned long long)peer_guid);
goto failed_proto;
}
/* FIXME don't use card->generation */
if (peer->node_id != source_node_id ||
peer->generation != dev->card->generation) {
fw_notify("Internal error: peer->node_id (%x) != "
"source_node_id (%x) or peer->generation (%x)"
" != dev->card->generation(%x)\n",
peer->node_id, source_node_id,
peer->generation, dev->card->generation);
peer->node_id = source_node_id;
peer->generation = dev->card->generation;
}
/* FIXME: for debugging */
if (sspd > SCODE_400)
sspd = SCODE_400;
/* Update our speed/payload/fifo_offset table */
/*
* FIXME: this does not handle cases where two high-speed endpoints must use a slower speed because of
* a lower speed hub between them. We need to look at the actual topology map here.
*/
peer->fifo = fifo_addr;
peer->max_payload = max_payload;
/*
* Only allow speeds to go down from their initial value.
* Otherwise a local peer that can only do S400 or slower may
* be told to transmit at S800 to a faster remote peer.
*/
if (peer->xmt_speed > sspd)
peer->xmt_speed = sspd;
/*
* Now that we're done with the 1394 specific stuff, we'll
* need to alter some of the data. Believe it or not, all
@ -764,10 +674,11 @@ static int fwnet_finish_incoming_packet(struct net_device *net,
}
static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
u16 source_node_id, bool is_broadcast)
int source_node_id, int generation,
bool is_broadcast)
{
struct sk_buff *skb;
struct net_device *net;
struct net_device *net = dev->netdev;
struct rfc2734_header hdr;
unsigned lf;
unsigned long flags;
@ -779,8 +690,6 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
int retval;
u16 ether_type;
net = dev->card->netdev;
hdr.w0 = be32_to_cpu(buf[0]);
lf = fwnet_get_hdr_lf(&hdr);
if (lf == RFC2374_HDR_UNFRAG) {
@ -819,9 +728,12 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
}
datagram_label = fwnet_get_hdr_dgl(&hdr);
dg_size = fwnet_get_hdr_dg_size(&hdr); /* ??? + 1 */
peer = fwnet_peer_find_by_node_id(dev, source_node_id);
spin_lock_irqsave(&peer->pdg_lock, flags);
spin_lock_irqsave(&dev->lock, flags);
peer = fwnet_peer_find_by_node_id(dev, source_node_id, generation);
if (!peer)
goto bad_proto;
pd = fwnet_pd_find(peer, datagram_label);
if (pd == NULL) {
@ -876,7 +788,7 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
skb = skb_get(pd->skb);
fwnet_pd_delete(pd);
spin_unlock_irqrestore(&peer->pdg_lock, flags);
spin_unlock_irqrestore(&dev->lock, flags);
return fwnet_finish_incoming_packet(net, skb, source_node_id,
false, ether_type);
@ -885,12 +797,12 @@ static int fwnet_incoming_packet(struct fwnet_device *dev, __be32 *buf, int len,
* Datagram is not complete, we're done for the
* moment.
*/
spin_unlock_irqrestore(&peer->pdg_lock, flags);
spin_unlock_irqrestore(&dev->lock, flags);
return 0;
bad_proto:
spin_unlock_irqrestore(&peer->pdg_lock, flags);
spin_unlock_irqrestore(&dev->lock, flags);
if (netif_queue_stopped(net))
netif_wake_queue(net);
@ -916,7 +828,8 @@ static void fwnet_receive_packet(struct fw_card *card, struct fw_request *r,
return;
}
status = fwnet_incoming_packet(dev, payload, length, source, false);
status = fwnet_incoming_packet(dev, payload, length,
source, generation, false);
if (status != 0) {
fw_error("Incoming packet failure\n");
fw_send_response(card, r, RCODE_CONFLICT_ERROR);
@ -966,7 +879,7 @@ static void fwnet_receive_broadcast(struct fw_iso_context *context,
buf_ptr += 2;
length -= IEEE1394_GASP_HDR_SIZE;
fwnet_incoming_packet(dev, buf_ptr, length,
source_node_id, true);
source_node_id, -1, true);
}
packet.payload_length = dev->rcv_buffer_size;
@ -1073,7 +986,6 @@ static int fwnet_send_packet(struct fwnet_packet_task *ptask)
unsigned tx_len;
struct rfc2734_header *bufhdr;
unsigned long flags;
struct net_device *net;
dev = ptask->dev;
tx_len = ptask->max_payload;
@ -1137,8 +1049,7 @@ static int fwnet_send_packet(struct fwnet_packet_task *ptask)
list_add_tail(&ptask->pt_link, &dev->sent_list);
spin_unlock_irqrestore(&dev->lock, flags);
net = dev->card->netdev;
net->trans_start = jiffies;
dev->netdev->trans_start = jiffies;
return 0;
}
@ -1294,7 +1205,8 @@ static int fwnet_tx(struct sk_buff *skb, struct net_device *net)
u16 dg_size;
u16 *datagram_label_ptr;
struct fwnet_packet_task *ptask;
struct fwnet_peer *peer = NULL;
struct fwnet_peer *peer;
unsigned long flags;
ptask = kmem_cache_alloc(fwnet_packet_task_cache, GFP_ATOMIC);
if (ptask == NULL)
@ -1314,6 +1226,9 @@ static int fwnet_tx(struct sk_buff *skb, struct net_device *net)
proto = hdr_buf.h_proto;
dg_size = skb->len;
/* serialize access to peer, including peer->datagram_label */
spin_lock_irqsave(&dev->lock, flags);
/*
* Set the transmission type for the packet. ARP packets and IP
* broadcast packets are sent via GASP.
@ -1334,23 +1249,18 @@ static int fwnet_tx(struct sk_buff *skb, struct net_device *net)
u8 generation;
peer = fwnet_peer_find_by_guid(dev, be64_to_cpu(guid));
if (!peer)
goto fail;
if (peer->fifo == FWNET_NO_FIFO_ADDR)
goto fail;
if (!peer || peer->fifo == FWNET_NO_FIFO_ADDR)
goto fail_unlock;
generation = peer->generation;
smp_rmb();
dest_node = peer->node_id;
max_payload = peer->max_payload;
datagram_label_ptr = &peer->datagram_label;
ptask->fifo_addr = peer->fifo;
ptask->generation = generation;
ptask->dest_node = dest_node;
ptask->speed = peer->xmt_speed;
ptask->speed = peer->speed;
}
/* If this is an ARP packet, convert it */
@ -1393,11 +1303,16 @@ static int fwnet_tx(struct sk_buff *skb, struct net_device *net)
ptask->outstanding_pkts = DIV_ROUND_UP(dg_size, max_payload);
max_payload += RFC2374_FRAG_HDR_SIZE;
}
spin_unlock_irqrestore(&dev->lock, flags);
ptask->max_payload = max_payload;
fwnet_send_packet(ptask);
return NETDEV_TX_OK;
fail_unlock:
spin_unlock_irqrestore(&dev->lock, flags);
fail:
if (ptask)
kmem_cache_free(fwnet_packet_task_cache, ptask);
@ -1467,7 +1382,48 @@ static void fwnet_init_dev(struct net_device *net)
SET_ETHTOOL_OPS(net, &fwnet_ethtool_ops);
}
/* FIXME create netdev upon first fw_unit of a card, not upon local fw_unit */
/* caller must hold fwnet_device_mutex */
static struct fwnet_device *fwnet_dev_find(struct fw_card *card)
{
struct fwnet_device *dev;
list_for_each_entry(dev, &fwnet_device_list, dev_link)
if (dev->card == card)
return dev;
return NULL;
}
static int fwnet_add_peer(struct fwnet_device *dev,
struct fw_unit *unit, struct fw_device *device)
{
struct fwnet_peer *peer;
peer = kmalloc(sizeof(*peer), GFP_KERNEL);
if (!peer)
return -ENOMEM;
unit->device.driver_data = peer;
peer->dev = dev;
peer->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
peer->fifo = FWNET_NO_FIFO_ADDR;
INIT_LIST_HEAD(&peer->pd_list);
peer->pdg_size = 0;
peer->datagram_label = 0;
peer->speed = device->max_speed;
peer->max_payload = fwnet_max_payload(device->max_rec, peer->speed);
peer->generation = device->generation;
smp_rmb();
peer->node_id = device->node_id;
spin_lock_irq(&dev->lock);
list_add_tail(&peer->peer_link, &dev->peer_list);
spin_unlock_irq(&dev->lock);
return 0;
}
static int fwnet_probe(struct device *_dev)
{
struct fw_unit *unit = fw_unit(_dev);
@ -1476,16 +1432,22 @@ static int fwnet_probe(struct device *_dev)
struct net_device *net;
struct fwnet_device *dev;
unsigned max_mtu;
bool new_netdev;
int ret;
if (!device->is_local) {
int added;
mutex_lock(&fwnet_device_mutex);
added = fwnet_peer_new(card, device);
return added;
dev = fwnet_dev_find(card);
if (dev) {
new_netdev = false;
net = dev->netdev;
goto have_dev;
}
new_netdev = true;
net = alloc_netdev(sizeof(*dev), "firewire%d", fwnet_init_dev);
if (net == NULL) {
fw_error("out of memory\n");
ret = -ENOMEM;
goto out;
}
@ -1500,12 +1462,13 @@ static int fwnet_probe(struct device *_dev)
dev->local_fifo = FWNET_NO_FIFO_ADDR;
/* INIT_WORK(&dev->wake, fwnet_handle_queue);*/
INIT_LIST_HEAD(&dev->packet_list);
INIT_LIST_HEAD(&dev->broadcasted_list);
INIT_LIST_HEAD(&dev->sent_list);
INIT_LIST_HEAD(&dev->peer_list);
dev->card = card;
dev->netdev = net;
/*
* Use the RFC 2734 default 1500 octets or the maximum payload
@ -1518,43 +1481,57 @@ static int fwnet_probe(struct device *_dev)
/* Set our hardware address while we're at it */
put_unaligned_be64(card->guid, net->dev_addr);
put_unaligned_be64(~0ULL, net->broadcast);
if (register_netdev(net)) {
ret = register_netdev(net);
if (ret) {
fw_error("Cannot register the driver\n");
goto out;
}
list_add_tail(&dev->dev_link, &fwnet_device_list);
fw_notify("%s: IPv4 over FireWire on device %016llx\n",
net->name, (unsigned long long)card->guid);
card->netdev = net;
return 0;
have_dev:
ret = fwnet_add_peer(dev, unit, device);
if (ret && new_netdev) {
unregister_netdev(net);
list_del(&dev->dev_link);
}
out:
if (net)
if (ret && new_netdev)
free_netdev(net);
return -ENOENT;
mutex_unlock(&fwnet_device_mutex);
return ret;
}
static void fwnet_remove_peer(struct fwnet_peer *peer)
{
struct fwnet_partial_datagram *pd, *pd_next;
spin_lock_irq(&peer->dev->lock);
list_del(&peer->peer_link);
spin_unlock_irq(&peer->dev->lock);
list_for_each_entry_safe(pd, pd_next, &peer->pd_list, pd_link)
fwnet_pd_delete(pd);
kfree(peer);
}
static int fwnet_remove(struct device *_dev)
{
struct fw_unit *unit = fw_unit(_dev);
struct fw_device *device = fw_parent_device(unit);
struct fw_card *card = device->card;
struct fwnet_peer *peer = _dev->driver_data;
struct fwnet_device *dev = peer->dev;
struct net_device *net;
struct fwnet_device *dev;
struct fwnet_peer *peer;
struct fwnet_partial_datagram *pd, *pd_next;
struct fwnet_packet_task *ptask, *pt_next;
if (!device->is_local) {
fwnet_peer_delete(card, device);
mutex_lock(&fwnet_device_mutex);
return 0;
}
fwnet_remove_peer(peer);
net = card->netdev;
if (net) {
dev = netdev_priv(net);
if (list_empty(&dev->peer_list)) {
net = dev->netdev;
unregister_netdev(net);
if (dev->local_fifo != FWNET_NO_FIFO_ADDR)
@ -1580,19 +1557,11 @@ static int fwnet_remove(struct device *_dev)
dev_kfree_skb_any(ptask->skb);
kmem_cache_free(fwnet_packet_task_cache, ptask);
}
list_for_each_entry(peer, &card->peer_list, peer_link) {
if (peer->pdg_size) {
list_for_each_entry_safe(pd, pd_next,
&peer->pd_list, pd_link)
fwnet_pd_delete(pd);
peer->pdg_size = 0;
}
peer->fifo = FWNET_NO_FIFO_ADDR;
}
free_netdev(net);
card->netdev = NULL;
}
mutex_unlock(&fwnet_device_mutex);
return 0;
}
@ -1603,24 +1572,15 @@ static int fwnet_remove(struct device *_dev)
static void fwnet_update(struct fw_unit *unit)
{
struct fw_device *device = fw_parent_device(unit);
struct net_device *net = device->card->netdev;
struct fwnet_device *dev;
struct fwnet_peer *peer;
u64 guid;
struct fwnet_peer *peer = unit->device.driver_data;
int generation;
if (net && !device->is_local) {
dev = netdev_priv(net);
guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
peer = fwnet_peer_find_by_guid(dev, guid);
if (!peer) {
fw_error("fwnet_update: no peer for device %016llx\n",
(unsigned long long)guid);
return;
}
peer->generation = device->generation;
rmb();
generation = device->generation;
spin_lock_irq(&peer->dev->lock);
peer->node_id = device->node_id;
}
peer->generation = generation;
spin_unlock_irq(&peer->dev->lock);
}
static const struct ieee1394_device_id fwnet_id_table[] = {

View File

@ -131,10 +131,6 @@ struct fw_card {
bool broadcast_channel_allocated;
u32 broadcast_channel;
u32 topology_map[(CSR_TOPOLOGY_MAP_END - CSR_TOPOLOGY_MAP) / 4];
/* firewire-net driver data */
void *netdev;
struct list_head peer_list;
};
static inline struct fw_card *fw_card_get(struct fw_card *card)