* [PATCHv3 net-next 2/4] caif: Add support for CAIF over CDC NCM USB interface
2011-12-04 21:22 [PATCHv3 net-next 1/4] if_ether.h: Add IEEE 802.1 Local Experimental Ethertype 1 Sjur Brændeland
@ 2011-12-04 21:22 ` Sjur Brændeland
2011-12-05 23:46 ` David Miller
2011-12-04 21:22 ` [PATCHv3 net-next 3/4] caif: Add support for flow-control on device's tx-queue Sjur Brændeland
` (2 subsequent siblings)
3 siblings, 1 reply; 8+ messages in thread
From: Sjur Brændeland @ 2011-12-04 21:22 UTC (permalink / raw)
To: netdev, David Miller; +Cc: Alexey Orishko, Eric Dumazet, Sjur Brændeland
NCM 1.0 does not support anything but Ethernet framing, hence
CAIF payload will be put into Ethernet frames.
Discovery is based on fixed USB vendor 0x04cc (ST-Ericsson),
product-id 0x230f (NCM). In this variant only CAIF payload is sent over
the NCM interface.
The CAIF stack (cfusbl.c) will when USB interface register first check if
we got a CDC NCM USB interface with the right VID, PID.
It will then read the device's Ethernet address and create a 'template'
Ethernet TX header, using a broadcast address as the destination address,
and EthType 0x88b5 (802.1 Local Experimental - vendor specific).
A protocol handler for 0x88b5 is setup for reception of CAIF frames from
the CDC NCM USB interface.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
---
Hi Dave,
>Please make this feature a tristate and make the init and exit
>routines executed via the normal modula_init()/module_exit()
>mechanisms.
>That way you don't need that dopey header file to export the
>init and exit routines, and you don't need to ifdef crap up the
>code CAIF code to invoke them.
Done.
Changes from V2:
o As suggested: Killed of header file and ifdefs, and made it tristate
o Renamed module name to caif_usb
o Exported a few functions
o Had to handle refcnt for caif_usb module when USB NCM device registers
and unregisters.
Regards,
Sjur
net/caif/Kconfig | 11 +++
net/caif/Makefile | 1 +
net/caif/caif_dev.c | 1 +
net/caif/caif_usb.c | 208 +++++++++++++++++++++++++++++++++++++++++++++++
net/caif/cfpkt_skbuff.c | 12 +--
5 files changed, 224 insertions(+), 9 deletions(-)
create mode 100644 net/caif/caif_usb.c
diff --git a/net/caif/Kconfig b/net/caif/Kconfig
index 529750d..936361e 100644
--- a/net/caif/Kconfig
+++ b/net/caif/Kconfig
@@ -40,3 +40,14 @@ config CAIF_NETDEV
If you select to build it as a built-in then the main CAIF device must
also be a built-in.
If unsure say Y.
+
+config CAIF_USB
+ tristate "CAIF USB support"
+ depends on CAIF
+ default n
+ ---help---
+ Say Y if you are using CAIF over USB CDC NCM.
+ This can be either built-in or a loadable module,
+ If you select to build it as a built-in then the main CAIF device must
+ also be a built-in.
+ If unsure say N.
diff --git a/net/caif/Makefile b/net/caif/Makefile
index ebcd4e7..cc2b511 100644
--- a/net/caif/Makefile
+++ b/net/caif/Makefile
@@ -10,5 +10,6 @@ caif-y := caif_dev.o \
obj-$(CONFIG_CAIF) += caif.o
obj-$(CONFIG_CAIF_NETDEV) += chnl_net.o
obj-$(CONFIG_CAIF) += caif_socket.o
+obj-$(CONFIG_CAIF_USB) += caif_usb.o
export-y := caif.o
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index f7e8c70..6acec19 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -262,6 +262,7 @@ void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
if (rcv_func)
*rcv_func = receive;
}
+EXPORT_SYMBOL(caif_enroll_dev);
/* notify Caif of device events */
static int caif_device_notify(struct notifier_block *me, unsigned long what,
diff --git a/net/caif/caif_usb.c b/net/caif/caif_usb.c
new file mode 100644
index 0000000..f5db57c
--- /dev/null
+++ b/net/caif/caif_usb.c
@@ -0,0 +1,208 @@
+/*
+ * CAIF USB handler
+ * Copyright (C) ST-Ericsson AB 2011
+ * Author: Sjur Brendeland/sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/usbnet.h>
+#include <net/netns/generic.h>
+#include <net/caif/caif_dev.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/cfcnfg.h>
+
+MODULE_LICENSE("GPL");
+
+#define CFUSB_PAD_DESCR_SZ 1 /* Alignment descriptor length */
+#define CFUSB_ALIGNMENT 4 /* Number of bytes to align. */
+#define CFUSB_MAX_HEADLEN (CFUSB_PAD_DESCR_SZ + CFUSB_ALIGNMENT-1)
+#define STE_USB_VID 0x04cc /* USB Product ID for ST-Ericsson */
+#define STE_USB_PID_CAIF 0x2306 /* Product id for CAIF Modems */
+
+struct cfusbl {
+ struct cflayer layer;
+ u8 tx_eth_hdr[ETH_HLEN];
+};
+
+static bool pack_added;
+
+static int cfusbl_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+ u8 hpad;
+
+ /* Remove padding. */
+ cfpkt_extr_head(pkt, &hpad, 1);
+ cfpkt_extr_head(pkt, NULL, hpad);
+ return layr->up->receive(layr->up, pkt);
+}
+
+static int cfusbl_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+ struct caif_payload_info *info;
+ u8 hpad;
+ u8 zeros[CFUSB_ALIGNMENT];
+ struct sk_buff *skb;
+ struct cfusbl *usbl = container_of(layr, struct cfusbl, layer);
+
+ skb = cfpkt_tonative(pkt);
+
+ skb_reset_network_header(skb);
+ skb->protocol = htons(ETH_P_IP);
+
+ info = cfpkt_info(pkt);
+ hpad = (info->hdr_len + CFUSB_PAD_DESCR_SZ) & (CFUSB_ALIGNMENT - 1);
+
+ if (skb_headroom(skb) < ETH_HLEN + CFUSB_PAD_DESCR_SZ + hpad) {
+ pr_warn("Headroom to small\n");
+ kfree_skb(skb);
+ return -EIO;
+ }
+ memset(zeros, 0, hpad);
+
+ cfpkt_add_head(pkt, zeros, hpad);
+ cfpkt_add_head(pkt, &hpad, 1);
+ cfpkt_add_head(pkt, usbl->tx_eth_hdr, sizeof(usbl->tx_eth_hdr));
+ return layr->dn->transmit(layr->dn, pkt);
+}
+
+static void cfusbl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+ int phyid)
+{
+ if (layr->up && layr->up->ctrlcmd)
+ layr->up->ctrlcmd(layr->up, ctrl, layr->id);
+}
+
+struct cflayer *cfusbl_create(int phyid, u8 ethaddr[ETH_ALEN],
+ u8 braddr[ETH_ALEN])
+{
+ struct cfusbl *this = kmalloc(sizeof(struct cfusbl), GFP_ATOMIC);
+
+ if (!this) {
+ pr_warn("Out of memory\n");
+ return NULL;
+ }
+ caif_assert(offsetof(struct cfusbl, layer) == 0);
+
+ memset(this, 0, sizeof(struct cflayer));
+ this->layer.receive = cfusbl_receive;
+ this->layer.transmit = cfusbl_transmit;
+ this->layer.ctrlcmd = cfusbl_ctrlcmd;
+ snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "usb%d", phyid);
+ this->layer.id = phyid;
+
+ /*
+ * Construct TX ethernet header:
+ * 0-5 destination address
+ * 5-11 source address
+ * 12-13 protocol type
+ */
+ memcpy(&this->tx_eth_hdr[ETH_ALEN], braddr, ETH_ALEN);
+ memcpy(&this->tx_eth_hdr[ETH_ALEN], ethaddr, ETH_ALEN);
+ this->tx_eth_hdr[12] = cpu_to_be16(ETH_P_802_EX1) & 0xff;
+ this->tx_eth_hdr[13] = (cpu_to_be16(ETH_P_802_EX1) >> 8) & 0xff;
+ pr_debug("caif ethernet TX-header dst:%pM src:%pM type:%02x%02x\n",
+ this->tx_eth_hdr, this->tx_eth_hdr + ETH_ALEN,
+ this->tx_eth_hdr[12], this->tx_eth_hdr[13]);
+
+ return (struct cflayer *) this;
+}
+
+static struct packet_type caif_usb_type __read_mostly = {
+ .type = cpu_to_be16(ETH_P_802_EX1),
+};
+
+static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
+ void *arg)
+{
+ struct net_device *dev = arg;
+ struct caif_dev_common common;
+ struct cflayer *layer, *link_support;
+ struct usbnet *usbnet = netdev_priv(dev);
+ struct usb_device *usbdev = usbnet->udev;
+ struct ethtool_drvinfo drvinfo;
+
+ /*
+ * Quirks: High-jack ethtool to find if we have a NCM device,
+ * and find it's VID/PID.
+ */
+ if (dev->ethtool_ops == NULL || dev->ethtool_ops->get_drvinfo == NULL)
+ return 0;
+
+ dev->ethtool_ops->get_drvinfo(dev, &drvinfo);
+ if (strncmp(drvinfo.driver, "cdc_ncm", 7) != 0)
+ return 0;
+
+ pr_debug("USB CDC NCM device VID:0x%4x PID:0x%4x\n",
+ le16_to_cpu(usbdev->descriptor.idVendor),
+ le16_to_cpu(usbdev->descriptor.idProduct));
+
+ /* Check for VID/PID that supports CAIF */
+ if (!(le16_to_cpu(usbdev->descriptor.idVendor) == STE_USB_VID &&
+ le16_to_cpu(usbdev->descriptor.idProduct) == STE_USB_PID_CAIF))
+ return 0;
+
+ if (what == NETDEV_UNREGISTER)
+ module_put(THIS_MODULE);
+
+ if (what != NETDEV_REGISTER)
+ return 0;
+
+ __module_get(THIS_MODULE);
+
+ memset(&common, 0, sizeof(common));
+ common.use_frag = false;
+ common.use_fcs = false;
+ common.use_stx = false;
+ common.link_select = CAIF_LINK_HIGH_BANDW;
+ common.flowctrl = NULL;
+
+ link_support = cfusbl_create(dev->ifindex, dev->dev_addr,
+ dev->broadcast);
+
+ if (!link_support)
+ return -ENOMEM;
+
+ if (dev->num_tx_queues > 1)
+ pr_warn("USB device uses more than one tx queue\n");
+
+ caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN,
+ &layer, &caif_usb_type.func);
+ if (!pack_added)
+ dev_add_pack(&caif_usb_type);
+ pack_added = 1;
+
+ strncpy(layer->name, dev->name,
+ sizeof(layer->name) - 1);
+ layer->name[sizeof(layer->name) - 1] = 0;
+
+ return 0;
+}
+
+static struct notifier_block caif_device_notifier = {
+ .notifier_call = cfusbl_device_notify,
+ .priority = 0,
+};
+
+static int __init cfusbl_init(void)
+{
+ return register_netdevice_notifier(&caif_device_notifier);
+}
+
+static void __exit cfusbl_exit(void)
+{
+ unregister_netdevice_notifier(&caif_device_notifier);
+ dev_remove_pack(&caif_usb_type);
+}
+
+module_init(cfusbl_init);
+module_exit(cfusbl_exit);
diff --git a/net/caif/cfpkt_skbuff.c b/net/caif/cfpkt_skbuff.c
index de53907..e335ba8 100644
--- a/net/caif/cfpkt_skbuff.c
+++ b/net/caif/cfpkt_skbuff.c
@@ -63,7 +63,6 @@ static inline struct cfpkt *skb_to_pkt(struct sk_buff *skb)
return (struct cfpkt *) skb;
}
-
struct cfpkt *cfpkt_fromnative(enum caif_direction dir, void *nativepkt)
{
struct cfpkt *pkt = skb_to_pkt(nativepkt);
@@ -105,14 +104,12 @@ void cfpkt_destroy(struct cfpkt *pkt)
kfree_skb(skb);
}
-
inline bool cfpkt_more(struct cfpkt *pkt)
{
struct sk_buff *skb = pkt_to_skb(pkt);
return skb->len > 0;
}
-
int cfpkt_peek_head(struct cfpkt *pkt, void *data, u16 len)
{
struct sk_buff *skb = pkt_to_skb(pkt);
@@ -148,6 +145,7 @@ int cfpkt_extr_head(struct cfpkt *pkt, void *data, u16 len)
memcpy(data, from, len);
return 0;
}
+EXPORT_SYMBOL(cfpkt_extr_head);
int cfpkt_extr_trail(struct cfpkt *pkt, void *dta, u16 len)
{
@@ -171,13 +169,11 @@ int cfpkt_extr_trail(struct cfpkt *pkt, void *dta, u16 len)
return 0;
}
-
int cfpkt_pad_trail(struct cfpkt *pkt, u16 len)
{
return cfpkt_add_body(pkt, NULL, len);
}
-
int cfpkt_add_body(struct cfpkt *pkt, const void *data, u16 len)
{
struct sk_buff *skb = pkt_to_skb(pkt);
@@ -256,21 +252,19 @@ int cfpkt_add_head(struct cfpkt *pkt, const void *data2, u16 len)
memcpy(to, data, len);
return 0;
}
-
+EXPORT_SYMBOL(cfpkt_add_head);
inline int cfpkt_add_trail(struct cfpkt *pkt, const void *data, u16 len)
{
return cfpkt_add_body(pkt, data, len);
}
-
inline u16 cfpkt_getlen(struct cfpkt *pkt)
{
struct sk_buff *skb = pkt_to_skb(pkt);
return skb->len;
}
-
inline u16 cfpkt_iterate(struct cfpkt *pkt,
u16 (*iter_func)(u16, void *, u16),
u16 data)
@@ -288,7 +282,6 @@ inline u16 cfpkt_iterate(struct cfpkt *pkt,
return iter_func(data, pkt->skb.data, cfpkt_getlen(pkt));
}
-
int cfpkt_setlen(struct cfpkt *pkt, u16 len)
{
struct sk_buff *skb = pkt_to_skb(pkt);
@@ -400,3 +393,4 @@ struct caif_payload_info *cfpkt_info(struct cfpkt *pkt)
{
return (struct caif_payload_info *)&pkt_to_skb(pkt)->cb;
}
+EXPORT_SYMBOL(cfpkt_info);
--
1.7.0.4
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCHv3 net-next 3/4] caif: Add support for flow-control on device's tx-queue
2011-12-04 21:22 [PATCHv3 net-next 1/4] if_ether.h: Add IEEE 802.1 Local Experimental Ethertype 1 Sjur Brændeland
2011-12-04 21:22 ` [PATCHv3 net-next 2/4] caif: Add support for CAIF over CDC NCM USB interface Sjur Brændeland
@ 2011-12-04 21:22 ` Sjur Brændeland
2011-12-05 23:46 ` David Miller
2011-12-04 21:22 ` [PATCHv3 net-next 4/4] caif: Stash away hijacked skb destructor and call it later Sjur Brændeland
2011-12-05 23:46 ` [PATCHv3 net-next 1/4] if_ether.h: Add IEEE 802.1 Local Experimental Ethertype 1 David Miller
3 siblings, 1 reply; 8+ messages in thread
From: Sjur Brændeland @ 2011-12-04 21:22 UTC (permalink / raw)
To: netdev, David Miller; +Cc: Alexey Orishko, Eric Dumazet, Sjur Brændeland
Flow control is implemented by inspecting the qdisc queue length
in order to detect potential overflow on the TX queue. When a threshold
is reached flow-off is sent upwards in the CAIF stack. At the same time
the skb->destructor is hi-jacked by orphaning the SKB and the original
destructor is replaced with a "flow-on" callback. When the "hi-jacked"
SKB is consumed the queue should be empty, and the "flow-on" callback
is called and xon is sent upwards in the CAIF stack.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
---
net/caif/caif_dev.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 84 insertions(+), 1 deletions(-)
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index 6acec19..74c1273 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -17,6 +17,7 @@
#include <linux/netdevice.h>
#include <linux/mutex.h>
#include <linux/module.h>
+#include <linux/spinlock.h>
#include <net/netns/generic.h>
#include <net/net_namespace.h>
#include <net/pkt_sched.h>
@@ -34,6 +35,8 @@ struct caif_device_entry {
struct list_head list;
struct net_device *netdev;
int __percpu *pcpu_refcnt;
+ spinlock_t flow_lock;
+ bool xoff;
};
struct caif_device_entry_list {
@@ -48,6 +51,7 @@ struct caif_net {
};
static int caif_net_id;
+static int q_high = 50; /* Percent */
struct cfcnfg *get_cfcnfg(struct net *net)
{
@@ -126,17 +130,94 @@ static struct caif_device_entry *caif_get(struct net_device *dev)
return NULL;
}
+void caif_flow_cb(struct sk_buff *skb)
+{
+ struct caif_device_entry *caifd;
+ bool send_xoff;
+
+ WARN_ON(skb->dev == NULL);
+
+ rcu_read_lock();
+ caifd = caif_get(skb->dev);
+ caifd_hold(caifd);
+ rcu_read_unlock();
+
+ spin_lock_bh(&caifd->flow_lock);
+ send_xoff = caifd->xoff;
+ caifd->xoff = 0;
+ spin_unlock_bh(&caifd->flow_lock);
+
+ if (send_xoff)
+ caifd->layer.up->
+ ctrlcmd(caifd->layer.up,
+ _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND,
+ caifd->layer.id);
+ caifd_put(caifd);
+}
+
static int transmit(struct cflayer *layer, struct cfpkt *pkt)
{
- int err;
+ int err, high = 0, qlen = 0;
+ struct caif_dev_common *caifdev;
struct caif_device_entry *caifd =
container_of(layer, struct caif_device_entry, layer);
struct sk_buff *skb;
+ struct netdev_queue *txq;
+
+ rcu_read_lock_bh();
skb = cfpkt_tonative(pkt);
skb->dev = caifd->netdev;
skb_reset_network_header(skb);
skb->protocol = htons(ETH_P_CAIF);
+ caifdev = netdev_priv(caifd->netdev);
+
+ /* Check if we need to handle xoff */
+ if (likely(caifd->netdev->tx_queue_len == 0))
+ goto noxoff;
+
+ if (unlikely(caifd->xoff))
+ goto noxoff;
+
+ if (likely(!netif_queue_stopped(caifd->netdev))) {
+ /* If we run with a TX queue, check if the queue is too long*/
+ txq = netdev_get_tx_queue(skb->dev, 0);
+ qlen = qdisc_qlen(rcu_dereference_bh(txq->qdisc));
+
+ if (likely(qlen == 0))
+ goto noxoff;
+
+ high = (caifd->netdev->tx_queue_len * q_high) / 100;
+ if (likely(qlen < high))
+ goto noxoff;
+ }
+
+ /* Hold lock while accessing xoff */
+ spin_lock_bh(&caifd->flow_lock);
+ if (caifd->xoff) {
+ spin_unlock_bh(&caifd->flow_lock);
+ goto noxoff;
+ }
+
+ /*
+ * Handle flow off, we do this by temporary hi-jacking this
+ * skb's destructor function, and replace it with our own
+ * flow-on callback. The callback will set flow-on and call
+ * the original destructor.
+ */
+
+ pr_debug("queue has stopped(%d) or is full (%d > %d)\n",
+ netif_queue_stopped(caifd->netdev),
+ qlen, high);
+ caifd->xoff = 1;
+ spin_unlock_bh(&caifd->flow_lock);
+ skb_orphan(skb);
+
+ caifd->layer.up->ctrlcmd(caifd->layer.up,
+ _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND,
+ caifd->layer.id);
+noxoff:
+ rcu_read_unlock_bh();
err = dev_queue_xmit(skb);
if (err > 0)
@@ -232,6 +313,7 @@ void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
if (!caifd)
return;
*layer = &caifd->layer;
+ spin_lock_init(&caifd->flow_lock);
switch (caifdev->link_select) {
case CAIF_LINK_HIGH_BANDW:
@@ -316,6 +398,7 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
break;
}
+ caifd->xoff = 0;
cfcnfg_set_phy_state(cfg, &caifd->layer, true);
rcu_read_unlock();
--
1.7.0.4
^ permalink raw reply related [flat|nested] 8+ messages in thread