/
usbnet.c
2216 lines (1885 loc) · 57.9 KB
/
usbnet.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* USB Network driver infrastructure
* Copyright (C) 2000-2005 by David Brownell
* Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
*/
/*
* This is a generic "USB networking" framework that works with several
* kinds of full and high speed networking devices: host-to-host cables,
* smart usb peripherals, and actual Ethernet adapters.
*
* These devices usually differ in terms of control protocols (if they
* even have one!) and sometimes they define new framing to wrap or batch
* Ethernet packets. Otherwise, they talk to USB pretty much the same,
* so interface (un)binding, endpoint I/O queues, fault handling, and other
* issues can usefully be addressed by this framework.
*/
// #define DEBUG // error path messages, extra info
// #define VERBOSE // more; success messages
#include <linux/module.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ctype.h>
#include <linux/ethtool.h>
#include <linux/workqueue.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/usb/usbnet.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/pm_runtime.h>
/*-------------------------------------------------------------------------*/
/*
* Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
* Several dozen bytes of IPv4 data can fit in two such transactions.
* One maximum size Ethernet packet takes twenty four of them.
* For high speed, each frame comfortably fits almost 36 max size
* Ethernet packets (so queues should be bigger).
*
* The goal is to let the USB host controller be busy for 5msec or
* more before an irq is required, under load. Jumbograms change
* the equation.
*/
#define MAX_QUEUE_MEMORY (60 * 1518)
#define RX_QLEN(dev) ((dev)->rx_qlen)
#define TX_QLEN(dev) ((dev)->tx_qlen)
// reawaken network queue this soon after stopping; else watchdog barks
#define TX_TIMEOUT_JIFFIES (5*HZ)
/* throttle rx/tx briefly after some faults, so hub_wq might disconnect()
* us (it polls at HZ/4 usually) before we report too many false errors.
*/
#define THROTTLE_JIFFIES (HZ/8)
// between wakeups
#define UNLINK_TIMEOUT_MS 3
/*-------------------------------------------------------------------------*/
// randomly generated ethernet address
static u8 node_id [ETH_ALEN];
/* use ethtool to change the level for any given device */
static int msg_level = -1;
module_param (msg_level, int, 0);
MODULE_PARM_DESC (msg_level, "Override default message level");
/*-------------------------------------------------------------------------*/
static const char * const usbnet_event_names[] = {
[EVENT_TX_HALT] = "EVENT_TX_HALT",
[EVENT_RX_HALT] = "EVENT_RX_HALT",
[EVENT_RX_MEMORY] = "EVENT_RX_MEMORY",
[EVENT_STS_SPLIT] = "EVENT_STS_SPLIT",
[EVENT_LINK_RESET] = "EVENT_LINK_RESET",
[EVENT_RX_PAUSED] = "EVENT_RX_PAUSED",
[EVENT_DEV_ASLEEP] = "EVENT_DEV_ASLEEP",
[EVENT_DEV_OPEN] = "EVENT_DEV_OPEN",
[EVENT_DEVICE_REPORT_IDLE] = "EVENT_DEVICE_REPORT_IDLE",
[EVENT_NO_RUNTIME_PM] = "EVENT_NO_RUNTIME_PM",
[EVENT_RX_KILL] = "EVENT_RX_KILL",
[EVENT_LINK_CHANGE] = "EVENT_LINK_CHANGE",
[EVENT_SET_RX_MODE] = "EVENT_SET_RX_MODE",
[EVENT_NO_IP_ALIGN] = "EVENT_NO_IP_ALIGN",
};
/* handles CDC Ethernet and many other network "bulk data" interfaces */
int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
{
int tmp;
struct usb_host_interface *alt = NULL;
struct usb_host_endpoint *in = NULL, *out = NULL;
struct usb_host_endpoint *status = NULL;
for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
unsigned ep;
in = out = status = NULL;
alt = intf->altsetting + tmp;
/* take the first altsetting with in-bulk + out-bulk;
* remember any status endpoint, just in case;
* ignore other endpoints and altsettings.
*/
for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
struct usb_host_endpoint *e;
int intr = 0;
e = alt->endpoint + ep;
/* ignore endpoints which cannot transfer data */
if (!usb_endpoint_maxp(&e->desc))
continue;
switch (e->desc.bmAttributes) {
case USB_ENDPOINT_XFER_INT:
if (!usb_endpoint_dir_in(&e->desc))
continue;
intr = 1;
fallthrough;
case USB_ENDPOINT_XFER_BULK:
break;
default:
continue;
}
if (usb_endpoint_dir_in(&e->desc)) {
if (!intr && !in)
in = e;
else if (intr && !status)
status = e;
} else {
if (!out)
out = e;
}
}
if (in && out)
break;
}
if (!alt || !in || !out)
return -EINVAL;
if (alt->desc.bAlternateSetting != 0 ||
!(dev->driver_info->flags & FLAG_NO_SETINT)) {
tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
alt->desc.bAlternateSetting);
if (tmp < 0)
return tmp;
}
dev->in = usb_rcvbulkpipe (dev->udev,
in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
dev->out = usb_sndbulkpipe (dev->udev,
out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
dev->status = status;
return 0;
}
EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
{
u8 addr[ETH_ALEN];
int tmp = -1, ret;
unsigned char buf [13];
ret = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
if (ret == 12)
tmp = hex2bin(addr, buf, 6);
if (tmp < 0) {
dev_dbg(&dev->udev->dev,
"bad MAC string %d fetch, %d\n", iMACAddress, tmp);
if (ret >= 0)
ret = -EINVAL;
return ret;
}
eth_hw_addr_set(dev->net, addr);
return 0;
}
EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
static void intr_complete (struct urb *urb)
{
struct usbnet *dev = urb->context;
int status = urb->status;
switch (status) {
/* success */
case 0:
dev->driver_info->status(dev, urb);
break;
/* software-driven interface shutdown */
case -ENOENT: /* urb killed */
case -ESHUTDOWN: /* hardware gone */
netif_dbg(dev, ifdown, dev->net,
"intr shutdown, code %d\n", status);
return;
/* NOTE: not throttling like RX/TX, since this endpoint
* already polls infrequently
*/
default:
netdev_dbg(dev->net, "intr status %d\n", status);
break;
}
status = usb_submit_urb (urb, GFP_ATOMIC);
if (status != 0)
netif_err(dev, timer, dev->net,
"intr resubmit --> %d\n", status);
}
static int init_status (struct usbnet *dev, struct usb_interface *intf)
{
char *buf = NULL;
unsigned pipe = 0;
unsigned maxp;
unsigned period;
if (!dev->driver_info->status)
return 0;
pipe = usb_rcvintpipe (dev->udev,
dev->status->desc.bEndpointAddress
& USB_ENDPOINT_NUMBER_MASK);
maxp = usb_maxpacket (dev->udev, pipe, 0);
/* avoid 1 msec chatter: min 8 msec poll rate */
period = max ((int) dev->status->desc.bInterval,
(dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
buf = kmalloc (maxp, GFP_KERNEL);
if (buf) {
dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
if (!dev->interrupt) {
kfree (buf);
return -ENOMEM;
} else {
usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
buf, maxp, intr_complete, dev, period);
dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
dev_dbg(&intf->dev,
"status ep%din, %d bytes period %d\n",
usb_pipeendpoint(pipe), maxp, period);
}
}
return 0;
}
/* Submit the interrupt URB if not previously submitted, increasing refcount */
int usbnet_status_start(struct usbnet *dev, gfp_t mem_flags)
{
int ret = 0;
WARN_ON_ONCE(dev->interrupt == NULL);
if (dev->interrupt) {
mutex_lock(&dev->interrupt_mutex);
if (++dev->interrupt_count == 1)
ret = usb_submit_urb(dev->interrupt, mem_flags);
dev_dbg(&dev->udev->dev, "incremented interrupt URB count to %d\n",
dev->interrupt_count);
mutex_unlock(&dev->interrupt_mutex);
}
return ret;
}
EXPORT_SYMBOL_GPL(usbnet_status_start);
/* For resume; submit interrupt URB if previously submitted */
static int __usbnet_status_start_force(struct usbnet *dev, gfp_t mem_flags)
{
int ret = 0;
mutex_lock(&dev->interrupt_mutex);
if (dev->interrupt_count) {
ret = usb_submit_urb(dev->interrupt, mem_flags);
dev_dbg(&dev->udev->dev,
"submitted interrupt URB for resume\n");
}
mutex_unlock(&dev->interrupt_mutex);
return ret;
}
/* Kill the interrupt URB if all submitters want it killed */
void usbnet_status_stop(struct usbnet *dev)
{
if (dev->interrupt) {
mutex_lock(&dev->interrupt_mutex);
WARN_ON(dev->interrupt_count == 0);
if (dev->interrupt_count && --dev->interrupt_count == 0)
usb_kill_urb(dev->interrupt);
dev_dbg(&dev->udev->dev,
"decremented interrupt URB count to %d\n",
dev->interrupt_count);
mutex_unlock(&dev->interrupt_mutex);
}
}
EXPORT_SYMBOL_GPL(usbnet_status_stop);
/* For suspend; always kill interrupt URB */
static void __usbnet_status_stop_force(struct usbnet *dev)
{
if (dev->interrupt) {
mutex_lock(&dev->interrupt_mutex);
usb_kill_urb(dev->interrupt);
dev_dbg(&dev->udev->dev, "killed interrupt URB for suspend\n");
mutex_unlock(&dev->interrupt_mutex);
}
}
/* Passes this packet up the stack, updating its accounting.
* Some link protocols batch packets, so their rx_fixup paths
* can return clones as well as just modify the original skb.
*/
void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
{
struct pcpu_sw_netstats *stats64 = this_cpu_ptr(dev->net->tstats);
unsigned long flags;
int status;
if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
skb_queue_tail(&dev->rxq_pause, skb);
return;
}
/* only update if unset to allow minidriver rx_fixup override */
if (skb->protocol == 0)
skb->protocol = eth_type_trans (skb, dev->net);
flags = u64_stats_update_begin_irqsave(&stats64->syncp);
stats64->rx_packets++;
stats64->rx_bytes += skb->len;
u64_stats_update_end_irqrestore(&stats64->syncp, flags);
netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
skb->len + sizeof (struct ethhdr), skb->protocol);
memset (skb->cb, 0, sizeof (struct skb_data));
if (skb_defer_rx_timestamp(skb))
return;
status = netif_rx (skb);
if (status != NET_RX_SUCCESS)
netif_dbg(dev, rx_err, dev->net,
"netif_rx status %d\n", status);
}
EXPORT_SYMBOL_GPL(usbnet_skb_return);
/* must be called if hard_mtu or rx_urb_size changed */
void usbnet_update_max_qlen(struct usbnet *dev)
{
enum usb_device_speed speed = dev->udev->speed;
if (!dev->rx_urb_size || !dev->hard_mtu)
goto insanity;
switch (speed) {
case USB_SPEED_HIGH:
dev->rx_qlen = MAX_QUEUE_MEMORY / dev->rx_urb_size;
dev->tx_qlen = MAX_QUEUE_MEMORY / dev->hard_mtu;
break;
case USB_SPEED_SUPER:
case USB_SPEED_SUPER_PLUS:
/*
* Not take default 5ms qlen for super speed HC to
* save memory, and iperf tests show 2.5ms qlen can
* work well
*/
dev->rx_qlen = 5 * MAX_QUEUE_MEMORY / dev->rx_urb_size;
dev->tx_qlen = 5 * MAX_QUEUE_MEMORY / dev->hard_mtu;
break;
default:
insanity:
dev->rx_qlen = dev->tx_qlen = 4;
}
}
EXPORT_SYMBOL_GPL(usbnet_update_max_qlen);
/*-------------------------------------------------------------------------
*
* Network Device Driver (peer link to "Host Device", from USB host)
*
*-------------------------------------------------------------------------*/
int usbnet_change_mtu (struct net_device *net, int new_mtu)
{
struct usbnet *dev = netdev_priv(net);
int ll_mtu = new_mtu + net->hard_header_len;
int old_hard_mtu = dev->hard_mtu;
int old_rx_urb_size = dev->rx_urb_size;
// no second zero-length packet read wanted after mtu-sized packets
if ((ll_mtu % dev->maxpacket) == 0)
return -EDOM;
net->mtu = new_mtu;
dev->hard_mtu = net->mtu + net->hard_header_len;
if (dev->rx_urb_size == old_hard_mtu) {
dev->rx_urb_size = dev->hard_mtu;
if (dev->rx_urb_size > old_rx_urb_size) {
usbnet_pause_rx(dev);
usbnet_unlink_rx_urbs(dev);
usbnet_resume_rx(dev);
}
}
/* max qlen depend on hard_mtu and rx_urb_size */
usbnet_update_max_qlen(dev);
return 0;
}
EXPORT_SYMBOL_GPL(usbnet_change_mtu);
/* The caller must hold list->lock */
static void __usbnet_queue_skb(struct sk_buff_head *list,
struct sk_buff *newsk, enum skb_state state)
{
struct skb_data *entry = (struct skb_data *) newsk->cb;
__skb_queue_tail(list, newsk);
entry->state = state;
}
/*-------------------------------------------------------------------------*/
/* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
* completion callbacks. 2.5 should have fixed those bugs...
*/
static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
struct sk_buff_head *list, enum skb_state state)
{
unsigned long flags;
enum skb_state old_state;
struct skb_data *entry = (struct skb_data *) skb->cb;
spin_lock_irqsave(&list->lock, flags);
old_state = entry->state;
entry->state = state;
__skb_unlink(skb, list);
/* defer_bh() is never called with list == &dev->done.
* spin_lock_nested() tells lockdep that it is OK to take
* dev->done.lock here with list->lock held.
*/
spin_lock_nested(&dev->done.lock, SINGLE_DEPTH_NESTING);
__skb_queue_tail(&dev->done, skb);
if (dev->done.qlen == 1)
tasklet_schedule(&dev->bh);
spin_unlock(&dev->done.lock);
spin_unlock_irqrestore(&list->lock, flags);
return old_state;
}
/* some work can't be done in tasklets, so we use keventd
*
* NOTE: annoying asymmetry: if it's active, schedule_work() fails,
* but tasklet_schedule() doesn't. hope the failure is rare.
*/
void usbnet_defer_kevent (struct usbnet *dev, int work)
{
set_bit (work, &dev->flags);
if (!schedule_work (&dev->kevent))
netdev_dbg(dev->net, "kevent %s may have been dropped\n", usbnet_event_names[work]);
else
netdev_dbg(dev->net, "kevent %s scheduled\n", usbnet_event_names[work]);
}
EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
/*-------------------------------------------------------------------------*/
static void rx_complete (struct urb *urb);
static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
{
struct sk_buff *skb;
struct skb_data *entry;
int retval = 0;
unsigned long lockflags;
size_t size = dev->rx_urb_size;
/* prevent rx skb allocation when error ratio is high */
if (test_bit(EVENT_RX_KILL, &dev->flags)) {
usb_free_urb(urb);
return -ENOLINK;
}
if (test_bit(EVENT_NO_IP_ALIGN, &dev->flags))
skb = __netdev_alloc_skb(dev->net, size, flags);
else
skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
if (!skb) {
netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
usb_free_urb (urb);
return -ENOMEM;
}
entry = (struct skb_data *) skb->cb;
entry->urb = urb;
entry->dev = dev;
entry->length = 0;
usb_fill_bulk_urb (urb, dev->udev, dev->in,
skb->data, size, rx_complete, skb);
spin_lock_irqsave (&dev->rxq.lock, lockflags);
if (netif_running (dev->net) &&
netif_device_present (dev->net) &&
test_bit(EVENT_DEV_OPEN, &dev->flags) &&
!test_bit (EVENT_RX_HALT, &dev->flags) &&
!test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
case -EPIPE:
usbnet_defer_kevent (dev, EVENT_RX_HALT);
break;
case -ENOMEM:
usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
break;
case -ENODEV:
netif_dbg(dev, ifdown, dev->net, "device gone\n");
netif_device_detach (dev->net);
break;
case -EHOSTUNREACH:
retval = -ENOLINK;
break;
default:
netif_dbg(dev, rx_err, dev->net,
"rx submit, %d\n", retval);
tasklet_schedule (&dev->bh);
break;
case 0:
__usbnet_queue_skb(&dev->rxq, skb, rx_start);
}
} else {
netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
retval = -ENOLINK;
}
spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
if (retval) {
dev_kfree_skb_any (skb);
usb_free_urb (urb);
}
return retval;
}
/*-------------------------------------------------------------------------*/
static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
{
if (dev->driver_info->rx_fixup &&
!dev->driver_info->rx_fixup (dev, skb)) {
/* With RX_ASSEMBLE, rx_fixup() must update counters */
if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
dev->net->stats.rx_errors++;
goto done;
}
// else network stack removes extra byte if we forced a short packet
/* all data was already cloned from skb inside the driver */
if (dev->driver_info->flags & FLAG_MULTI_PACKET)
goto done;
if (skb->len < ETH_HLEN) {
dev->net->stats.rx_errors++;
dev->net->stats.rx_length_errors++;
netif_dbg(dev, rx_err, dev->net, "rx length %d\n", skb->len);
} else {
usbnet_skb_return(dev, skb);
return;
}
done:
skb_queue_tail(&dev->done, skb);
}
/*-------------------------------------------------------------------------*/
static void rx_complete (struct urb *urb)
{
struct sk_buff *skb = (struct sk_buff *) urb->context;
struct skb_data *entry = (struct skb_data *) skb->cb;
struct usbnet *dev = entry->dev;
int urb_status = urb->status;
enum skb_state state;
skb_put (skb, urb->actual_length);
state = rx_done;
entry->urb = NULL;
switch (urb_status) {
/* success */
case 0:
break;
/* stalls need manual reset. this is rare ... except that
* when going through USB 2.0 TTs, unplug appears this way.
* we avoid the highspeed version of the ETIMEDOUT/EILSEQ
* storm, recovering as needed.
*/
case -EPIPE:
dev->net->stats.rx_errors++;
usbnet_defer_kevent (dev, EVENT_RX_HALT);
fallthrough;
/* software-driven interface shutdown */
case -ECONNRESET: /* async unlink */
case -ESHUTDOWN: /* hardware gone */
netif_dbg(dev, ifdown, dev->net,
"rx shutdown, code %d\n", urb_status);
goto block;
/* we get controller i/o faults during hub_wq disconnect() delays.
* throttle down resubmits, to avoid log floods; just temporarily,
* so we still recover when the fault isn't a hub_wq delay.
*/
case -EPROTO:
case -ETIME:
case -EILSEQ:
dev->net->stats.rx_errors++;
if (!timer_pending (&dev->delay)) {
mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
netif_dbg(dev, link, dev->net,
"rx throttle %d\n", urb_status);
}
block:
state = rx_cleanup;
entry->urb = urb;
urb = NULL;
break;
/* data overrun ... flush fifo? */
case -EOVERFLOW:
dev->net->stats.rx_over_errors++;
fallthrough;
default:
state = rx_cleanup;
dev->net->stats.rx_errors++;
netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
break;
}
/* stop rx if packet error rate is high */
if (++dev->pkt_cnt > 30) {
dev->pkt_cnt = 0;
dev->pkt_err = 0;
} else {
if (state == rx_cleanup)
dev->pkt_err++;
if (dev->pkt_err > 20)
set_bit(EVENT_RX_KILL, &dev->flags);
}
state = defer_bh(dev, skb, &dev->rxq, state);
if (urb) {
if (netif_running (dev->net) &&
!test_bit (EVENT_RX_HALT, &dev->flags) &&
state != unlink_start) {
rx_submit (dev, urb, GFP_ATOMIC);
usb_mark_last_busy(dev->udev);
return;
}
usb_free_urb (urb);
}
netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
}
/*-------------------------------------------------------------------------*/
void usbnet_pause_rx(struct usbnet *dev)
{
set_bit(EVENT_RX_PAUSED, &dev->flags);
netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
}
EXPORT_SYMBOL_GPL(usbnet_pause_rx);
void usbnet_resume_rx(struct usbnet *dev)
{
struct sk_buff *skb;
int num = 0;
clear_bit(EVENT_RX_PAUSED, &dev->flags);
while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
usbnet_skb_return(dev, skb);
num++;
}
tasklet_schedule(&dev->bh);
netif_dbg(dev, rx_status, dev->net,
"paused rx queue disabled, %d skbs requeued\n", num);
}
EXPORT_SYMBOL_GPL(usbnet_resume_rx);
void usbnet_purge_paused_rxq(struct usbnet *dev)
{
skb_queue_purge(&dev->rxq_pause);
}
EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
/*-------------------------------------------------------------------------*/
// unlink pending rx/tx; completion handlers do all other cleanup
static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
{
unsigned long flags;
struct sk_buff *skb;
int count = 0;
spin_lock_irqsave (&q->lock, flags);
while (!skb_queue_empty(q)) {
struct skb_data *entry;
struct urb *urb;
int retval;
skb_queue_walk(q, skb) {
entry = (struct skb_data *) skb->cb;
if (entry->state != unlink_start)
goto found;
}
break;
found:
entry->state = unlink_start;
urb = entry->urb;
/*
* Get reference count of the URB to avoid it to be
* freed during usb_unlink_urb, which may trigger
* use-after-free problem inside usb_unlink_urb since
* usb_unlink_urb is always racing with .complete
* handler(include defer_bh).
*/
usb_get_urb(urb);
spin_unlock_irqrestore(&q->lock, flags);
// during some PM-driven resume scenarios,
// these (async) unlinks complete immediately
retval = usb_unlink_urb (urb);
if (retval != -EINPROGRESS && retval != 0)
netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
else
count++;
usb_put_urb(urb);
spin_lock_irqsave(&q->lock, flags);
}
spin_unlock_irqrestore (&q->lock, flags);
return count;
}
// Flush all pending rx urbs
// minidrivers may need to do this when the MTU changes
void usbnet_unlink_rx_urbs(struct usbnet *dev)
{
if (netif_running(dev->net)) {
(void) unlink_urbs (dev, &dev->rxq);
tasklet_schedule(&dev->bh);
}
}
EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
/*-------------------------------------------------------------------------*/
static void wait_skb_queue_empty(struct sk_buff_head *q)
{
unsigned long flags;
spin_lock_irqsave(&q->lock, flags);
while (!skb_queue_empty(q)) {
spin_unlock_irqrestore(&q->lock, flags);
schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
set_current_state(TASK_UNINTERRUPTIBLE);
spin_lock_irqsave(&q->lock, flags);
}
spin_unlock_irqrestore(&q->lock, flags);
}
// precondition: never called in_interrupt
static void usbnet_terminate_urbs(struct usbnet *dev)
{
DECLARE_WAITQUEUE(wait, current);
int temp;
/* ensure there are no more active urbs */
add_wait_queue(&dev->wait, &wait);
set_current_state(TASK_UNINTERRUPTIBLE);
temp = unlink_urbs(dev, &dev->txq) +
unlink_urbs(dev, &dev->rxq);
/* maybe wait for deletions to finish. */
wait_skb_queue_empty(&dev->rxq);
wait_skb_queue_empty(&dev->txq);
wait_skb_queue_empty(&dev->done);
netif_dbg(dev, ifdown, dev->net,
"waited for %d urb completions\n", temp);
set_current_state(TASK_RUNNING);
remove_wait_queue(&dev->wait, &wait);
}
int usbnet_stop (struct net_device *net)
{
struct usbnet *dev = netdev_priv(net);
const struct driver_info *info = dev->driver_info;
int retval, pm, mpn;
clear_bit(EVENT_DEV_OPEN, &dev->flags);
netif_stop_queue (net);
netif_info(dev, ifdown, dev->net,
"stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
net->stats.rx_packets, net->stats.tx_packets,
net->stats.rx_errors, net->stats.tx_errors);
/* to not race resume */
pm = usb_autopm_get_interface(dev->intf);
/* allow minidriver to stop correctly (wireless devices to turn off
* radio etc) */
if (info->stop) {
retval = info->stop(dev);
if (retval < 0)
netif_info(dev, ifdown, dev->net,
"stop fail (%d) usbnet usb-%s-%s, %s\n",
retval,
dev->udev->bus->bus_name, dev->udev->devpath,
info->description);
}
if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
usbnet_terminate_urbs(dev);
usbnet_status_stop(dev);
usbnet_purge_paused_rxq(dev);
mpn = !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
/* deferred work (task, timer, softirq) must also stop.
* can't flush_scheduled_work() until we drop rtnl (later),
* else workers could deadlock; so make workers a NOP.
*/
dev->flags = 0;
del_timer_sync (&dev->delay);
tasklet_kill (&dev->bh);
if (!pm)
usb_autopm_put_interface(dev->intf);
if (info->manage_power && mpn)
info->manage_power(dev, 0);
else
usb_autopm_put_interface(dev->intf);
return 0;
}
EXPORT_SYMBOL_GPL(usbnet_stop);
/*-------------------------------------------------------------------------*/
// posts reads, and enables write queuing
// precondition: never called in_interrupt
int usbnet_open (struct net_device *net)
{
struct usbnet *dev = netdev_priv(net);
int retval;
const struct driver_info *info = dev->driver_info;
if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
netif_info(dev, ifup, dev->net,
"resumption fail (%d) usbnet usb-%s-%s, %s\n",
retval,
dev->udev->bus->bus_name,
dev->udev->devpath,
info->description);
goto done_nopm;
}
// put into "known safe" state
if (info->reset && (retval = info->reset (dev)) < 0) {
netif_info(dev, ifup, dev->net,
"open reset fail (%d) usbnet usb-%s-%s, %s\n",
retval,
dev->udev->bus->bus_name,
dev->udev->devpath,
info->description);
goto done;
}
/* hard_mtu or rx_urb_size may change in reset() */
usbnet_update_max_qlen(dev);
// insist peer be connected
if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
netif_err(dev, ifup, dev->net, "can't open; %d\n", retval);
goto done;
}
/* start any status interrupt transfer */
if (dev->interrupt) {
retval = usbnet_status_start(dev, GFP_KERNEL);
if (retval < 0) {
netif_err(dev, ifup, dev->net,
"intr submit %d\n", retval);
goto done;
}
}
set_bit(EVENT_DEV_OPEN, &dev->flags);
netif_start_queue (net);
netif_info(dev, ifup, dev->net,
"open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
(int)RX_QLEN(dev), (int)TX_QLEN(dev),
dev->net->mtu,
(dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
(dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
(dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
(dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
(dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
"simple");
/* reset rx error state */
dev->pkt_cnt = 0;
dev->pkt_err = 0;
clear_bit(EVENT_RX_KILL, &dev->flags);
// delay posting reads until we're fully open
tasklet_schedule (&dev->bh);
if (info->manage_power) {
retval = info->manage_power(dev, 1);
if (retval < 0) {
retval = 0;
set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
} else {
usb_autopm_put_interface(dev->intf);
}
}
return retval;
done:
usb_autopm_put_interface(dev->intf);
done_nopm:
return retval;
}
EXPORT_SYMBOL_GPL(usbnet_open);
/*-------------------------------------------------------------------------*/
/* ethtool methods; minidrivers may need to add some more, but
* they'll probably want to use this base set.
*/
/* These methods are written on the assumption that the device
* uses MII
*/
int usbnet_get_link_ksettings_mii(struct net_device *net,
struct ethtool_link_ksettings *cmd)
{
struct usbnet *dev = netdev_priv(net);
if (!dev->mii.mdio_read)
return -EOPNOTSUPP;
mii_ethtool_get_link_ksettings(&dev->mii, cmd);
return 0;
}
EXPORT_SYMBOL_GPL(usbnet_get_link_ksettings_mii);
int usbnet_get_link_ksettings_internal(struct net_device *net,
struct ethtool_link_ksettings *cmd)
{
struct usbnet *dev = netdev_priv(net);
/* the assumption that speed is equal on tx and rx
* is deeply engrained into the networking layer.
* For wireless stuff it is not true.
* We assume that rx_speed matters more.
*/
if (dev->rx_speed != SPEED_UNSET)
cmd->base.speed = dev->rx_speed / 1000000;
else if (dev->tx_speed != SPEED_UNSET)
cmd->base.speed = dev->tx_speed / 1000000;
else
cmd->base.speed = SPEED_UNKNOWN;
return 0;