diff options
author | Stephen Rothwell <sfr@canb.auug.org.au> | 2010-07-21 13:25:32 +1000 |
---|---|---|
committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2010-07-21 13:25:32 +1000 |
commit | 44bdd9307bc0d8f26287f2f462c38ebd6745282f (patch) | |
tree | 30bc52222df0e930eaa2405438b87a8ef535986a /drivers/net | |
parent | 68fb5ce326a07062803f9eae6ba309ea387ec326 (diff) | |
parent | 17d1061f5d87eff7d50942399414845d1f7a8a08 (diff) |
Merge remote branch 'alacrity/linux-next'
Diffstat (limited to 'drivers/net')
-rw-r--r-- | drivers/net/Kconfig | 14 | ||||
-rw-r--r-- | drivers/net/Makefile | 1 | ||||
-rw-r--r-- | drivers/net/vbus-enet.c | 1560 |
3 files changed, 1575 insertions, 0 deletions
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 8c13df7fdc16..70b98e742c74 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -3336,4 +3336,18 @@ config VMXNET3 To compile this driver as a module, choose M here: the module will be called vmxnet3. +config VBUS_ENET + tristate "VBUS Ethernet Driver" + default n + depends on VBUS_PROXY + help + A virtualized 802.x network device based on the VBUS + "virtual-ethernet" interface. It can be used with any + hypervisor/kernel that supports the vbus+venet protocol. + +config VBUS_ENET_DEBUG + bool "Enable Debugging" + depends on VBUS_ENET + default n + endif # NETDEVICES diff --git a/drivers/net/Makefile b/drivers/net/Makefile index ce555819c8fc..9c0e68e3355a 100644 --- a/drivers/net/Makefile +++ b/drivers/net/Makefile @@ -290,6 +290,7 @@ obj-$(CONFIG_FS_ENET) += fs_enet/ obj-$(CONFIG_NETXEN_NIC) += netxen/ obj-$(CONFIG_NIU) += niu.o obj-$(CONFIG_VIRTIO_NET) += virtio_net.o +obj-$(CONFIG_VBUS_ENET) += vbus-enet.o obj-$(CONFIG_SFC) += sfc/ obj-$(CONFIG_WIMAX) += wimax/ diff --git a/drivers/net/vbus-enet.c b/drivers/net/vbus-enet.c new file mode 100644 index 000000000000..94b86d482cee --- /dev/null +++ b/drivers/net/vbus-enet.c @@ -0,0 +1,1560 @@ +/* + * vbus_enet - A virtualized 802.x network device based on the VBUS interface + * + * Copyright (C) 2009 Novell, Gregory Haskins <ghaskins@novell.com> + * + * Derived from the SNULL example from the book "Linux Device Drivers" by + * Alessandro Rubini, Jonathan Corbet, and Greg Kroah-Hartman, published + * by O'Reilly & Associates. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/moduleparam.h> + +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/interrupt.h> + +#include <linux/in.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/ethtool.h> +#include <linux/ip.h> +#include <linux/tcp.h> +#include <linux/skbuff.h> +#include <linux/ioq.h> +#include <linux/vbus_driver.h> + +#include <linux/in6.h> +#include <asm/checksum.h> + +#include <linux/venet.h> + +MODULE_AUTHOR("Gregory Haskins"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("virtual-ethernet"); +MODULE_VERSION("1"); + +static int rx_ringlen = 256; +module_param(rx_ringlen, int, 0444); +static int tx_ringlen = 256; +module_param(tx_ringlen, int, 0444); +static int sg_enabled = 1; +module_param(sg_enabled, int, 0444); + +#define PDEBUG(_dev, fmt, args...) dev_dbg(&(_dev)->dev, fmt, ## args) + +#define SG_DESC_SIZE VSG_DESC_SIZE(MAX_SKB_FRAGS) + +struct vbus_enet_queue { + struct ioq *queue; + struct ioq_notifier notifier; + unsigned long count; +}; + +struct vbus_enet_priv { + spinlock_t lock; + struct net_device *dev; + struct vbus_device_proxy *vdev; + struct napi_struct napi; + struct vbus_enet_queue rxq; + struct { + struct vbus_enet_queue veq; + struct tasklet_struct task; + struct sk_buff_head outstanding; + } tx; + bool sg; + struct { + bool enabled; + char *pool; + } pmtd; /* pre-mapped transmit descriptors */ + struct { + bool enabled; + bool linkstate; + bool txc; + unsigned long evsize; + struct vbus_enet_queue veq; + struct tasklet_struct task; + char *pool; + } evq; + struct { + bool available; + char *pool; + struct vbus_enet_queue pageq; + } l4ro; + + struct sk_buff *(*import)(struct vbus_enet_priv *priv, + struct ioq_ring_desc *desc); +}; + +static void vbus_enet_tx_reap(struct vbus_enet_priv *priv); + +static struct vbus_enet_priv * +napi_to_priv(struct napi_struct *napi) +{ + return container_of(napi, struct vbus_enet_priv, napi); +} + +static int +queue_init(struct vbus_enet_priv *priv, + struct vbus_enet_queue *q, + const char *name, + int qid, + size_t ringsize, + void (*func)(struct ioq_notifier *)) +{ + struct vbus_device_proxy *dev = priv->vdev; + int ret; + char _name[64]; + + if (name) + snprintf(_name, sizeof(_name), "%s-%s", priv->dev->name, name); + + ret = vbus_driver_ioq_alloc(dev, name ? _name : NULL, qid, 0, + ringsize, &q->queue); + if (ret < 0) + panic("ioq_alloc failed: %d\n", ret); + + if (func) { + q->notifier.signal = func; + q->queue->notifier = &q->notifier; + } + + q->count = ringsize; + + return 0; +} + +static int +devcall(struct vbus_enet_priv *priv, u32 func, void *data, size_t len) +{ + struct vbus_device_proxy *dev = priv->vdev; + + return dev->ops->call(dev, func, data, len, 0); +} + +/* + * --------------- + * rx descriptors + * --------------- + */ + +static void +rxdesc_alloc(struct vbus_enet_priv *priv, struct ioq_ring_desc *desc, size_t len) +{ + struct net_device *dev = priv->dev; + struct sk_buff *skb; + + len += ETH_HLEN; + + skb = netdev_alloc_skb(dev, len + NET_IP_ALIGN); + BUG_ON(!skb); + + skb_reserve(skb, NET_IP_ALIGN); /* align IP on 16B boundary */ + + if (priv->l4ro.available) { + /* + * We will populate an SG descriptor initially with one + * IOV filled with an MTU SKB. If the packet needs to be + * larger than MTU, the host will grab pages out of the + * page-queue and populate additional IOVs + */ + struct venet_sg *vsg = (struct venet_sg *)(unsigned long)desc->cookie; + struct venet_iov *iov = &vsg->iov[0]; + + memset(vsg, 0, SG_DESC_SIZE); + + vsg->cookie = (u64)(unsigned long)skb; + vsg->count = 1; + + iov->ptr = (u64)__pa(skb->data); + iov->len = len; + } else { + desc->cookie = (u64)(unsigned long)skb; + desc->ptr = cpu_to_le64(__pa(skb->data)); + desc->len = cpu_to_le64(len); /* total length */ + } + + desc->valid = 1; +} + +static void +rx_pageq_refill(struct vbus_enet_priv *priv, gfp_t gfp_mask) +{ + struct ioq *ioq = priv->l4ro.pageq.queue; + struct ioq_iterator iter; + int ret, added = 0; + + if (ioq_full(ioq, ioq_idxtype_inuse)) + /* nothing to do if the pageq is already fully populated */ + return; + + ret = ioq_iter_init(ioq, &iter, ioq_idxtype_inuse, 0); + BUG_ON(ret < 0); /* will never fail unless seriously broken */ + + ret = ioq_iter_seek(&iter, ioq_seek_tail, 0, 0); + BUG_ON(ret < 0); + + /* + * Now populate each descriptor with an empty page + */ + while (!iter.desc->sown) { + struct page *page = NULL; + + page = alloc_page(gfp_mask); + + if (!page) + break; + + added = 1; + iter.desc->cookie = (u64)(unsigned long)page; + iter.desc->ptr = cpu_to_le64(__pa(page_address(page))); + iter.desc->len = cpu_to_le64(PAGE_SIZE); + + ret = ioq_iter_push(&iter, 0); + BUG_ON(ret < 0); + } + + if (added) + ioq_signal(ioq, 0); +} + +static void +rx_setup(struct vbus_enet_priv *priv) +{ + struct ioq *ioq = priv->rxq.queue; + struct ioq_iterator iter; + int ret; + int i = 0; + + /* + * We want to iterate on the "valid" index. By default the iterator + * will not "autoupdate" which means it will not hypercall the host + * with our changes. This is good, because we are really just + * initializing stuff here anyway. Note that you can always manually + * signal the host with ioq_signal() if the autoupdate feature is not + * used. + */ + ret = ioq_iter_init(ioq, &iter, ioq_idxtype_valid, 0); + BUG_ON(ret < 0); /* will never fail unless seriously broken */ + + /* + * Seek to the tail of the valid index (which should be our first + * item, since the queue is brand-new) + */ + ret = ioq_iter_seek(&iter, ioq_seek_tail, 0, 0); + BUG_ON(ret < 0); + + /* + * Now populate each descriptor with an empty buffer and mark it valid + */ + while (!iter.desc->valid) { + if (priv->l4ro.available) { + size_t offset = (i * SG_DESC_SIZE); + void *addr = &priv->l4ro.pool[offset]; + + iter.desc->ptr = cpu_to_le64(offset); + iter.desc->cookie = (u64)(unsigned long)addr; + iter.desc->len = cpu_to_le64(SG_DESC_SIZE); + } + + rxdesc_alloc(priv, iter.desc, priv->dev->mtu); + + /* + * This push operation will simultaneously advance the + * valid-head index and increment our position in the queue + * by one. + */ + ret = ioq_iter_push(&iter, 0); + BUG_ON(ret < 0); + + i++; + } + + if (priv->l4ro.available) + rx_pageq_refill(priv, GFP_KERNEL); +} + +static void +rx_rxq_teardown(struct vbus_enet_priv *priv) +{ + struct ioq *ioq = priv->rxq.queue; + struct ioq_iterator iter; + int ret; + + ret = ioq_iter_init(ioq, &iter, ioq_idxtype_valid, 0); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_head, 0, 0); + BUG_ON(ret < 0); + + /* + * free each valid descriptor + */ + while (iter.desc->valid) { + struct sk_buff *skb; + + if (priv->l4ro.available) { + struct venet_sg *vsg; + int i; + + vsg = (struct venet_sg *)(unsigned long)iter.desc->cookie; + + /* skip i=0, since that is the skb->data IOV */ + for (i = 1; i < vsg->count; i++) { + struct venet_iov *iov = &vsg->iov[i]; + struct page *page = (struct page *)(unsigned long)iov->ptr; + + put_page(page); + } + + skb = (struct sk_buff *)(unsigned long)vsg->cookie; + } else + skb = (struct sk_buff *)(unsigned long)iter.desc->cookie; + + iter.desc->valid = 0; + wmb(); + + iter.desc->ptr = 0; + iter.desc->cookie = 0; + + ret = ioq_iter_pop(&iter, 0); + BUG_ON(ret < 0); + + dev_kfree_skb(skb); + } +} + +static void +rx_l4ro_teardown(struct vbus_enet_priv *priv) +{ + struct ioq *ioq = priv->l4ro.pageq.queue; + struct ioq_iterator iter; + int ret; + + ret = ioq_iter_init(ioq, &iter, ioq_idxtype_inuse, 0); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_head, 0, 0); + BUG_ON(ret < 0); + + /* + * free each valid descriptor + */ + while (iter.desc->sown) { + struct page *page = (struct page *)(unsigned long)iter.desc->cookie; + + iter.desc->valid = 0; + wmb(); + + iter.desc->ptr = 0; + iter.desc->cookie = 0; + + ret = ioq_iter_pop(&iter, 0); + BUG_ON(ret < 0); + + put_page(page); + } + + ioq_put(ioq); + kfree(priv->l4ro.pool); +} + +static void +rx_teardown(struct vbus_enet_priv *priv) +{ + rx_rxq_teardown(priv); + + if (priv->l4ro.available) + rx_l4ro_teardown(priv); +} + +static int +tx_setup(struct vbus_enet_priv *priv) +{ + struct ioq *ioq = priv->tx.veq.queue; + struct ioq_iterator iter; + int i; + int ret; + + if (!priv->sg) + /* + * There is nothing to do for a ring that is not using + * scatter-gather + */ + return 0; + + /* pre-allocate our descriptor pool if pmtd is enabled */ + if (priv->pmtd.enabled) { + struct vbus_device_proxy *dev = priv->vdev; + size_t poollen = SG_DESC_SIZE * priv->tx.veq.count; + char *pool; + int shmid; + + /* pmtdquery will return the shm-id to use for the pool */ + ret = devcall(priv, VENET_FUNC_PMTDQUERY, NULL, 0); + BUG_ON(ret < 0); + + shmid = ret; + + pool = kzalloc(poollen, GFP_KERNEL | GFP_DMA); + if (!pool) + return -ENOMEM; + + priv->pmtd.pool = pool; + + ret = dev->ops->shm(dev, NULL, shmid, 0, pool, poollen, + NULL, NULL, 0); + BUG_ON(ret < 0); + } + + ret = ioq_iter_init(ioq, &iter, ioq_idxtype_valid, 0); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_set, 0, 0); + BUG_ON(ret < 0); + + /* + * Now populate each descriptor with an empty SG descriptor + */ + for (i = 0; i < priv->tx.veq.count; i++) { + struct venet_sg *vsg; + + if (priv->pmtd.enabled) { + size_t offset = (i * SG_DESC_SIZE); + + vsg = (struct venet_sg *)&priv->pmtd.pool[offset]; + iter.desc->ptr = cpu_to_le64(offset); + } else { + vsg = kzalloc(SG_DESC_SIZE, GFP_KERNEL); + if (!vsg) + return -ENOMEM; + + iter.desc->ptr = cpu_to_le64(__pa(vsg)); + } + + iter.desc->cookie = (u64)(unsigned long)vsg; + iter.desc->len = cpu_to_le64(SG_DESC_SIZE); + + ret = ioq_iter_seek(&iter, ioq_seek_next, 0, 0); + BUG_ON(ret < 0); + } + + return 0; +} + +static void +tx_teardown(struct vbus_enet_priv *priv) +{ + struct ioq *ioq = priv->tx.veq.queue; + struct ioq_iterator iter; + struct sk_buff *skb; + int ret; + + /* forcefully free all outstanding transmissions */ + while ((skb = __skb_dequeue(&priv->tx.outstanding))) + dev_kfree_skb(skb); + + if (!priv->sg) + /* + * There is nothing else to do for a ring that is not using + * scatter-gather + */ + return; + + if (priv->pmtd.enabled) { + /* + * PMTD mode means we only need to free the pool + */ + kfree(priv->pmtd.pool); + return; + } + + ret = ioq_iter_init(ioq, &iter, ioq_idxtype_valid, 0); + BUG_ON(ret < 0); + + /* seek to position 0 */ + ret = ioq_iter_seek(&iter, ioq_seek_set, 0, 0); + BUG_ON(ret < 0); + + /* + * free each valid descriptor + */ + while (iter.desc->cookie) { + struct venet_sg *vsg = (struct venet_sg *)(unsigned long)iter.desc->cookie; + + iter.desc->valid = 0; + wmb(); + + iter.desc->ptr = 0; + iter.desc->cookie = 0; + + ret = ioq_iter_seek(&iter, ioq_seek_next, 0, 0); + BUG_ON(ret < 0); + + kfree(vsg); + } +} + +static void +evq_teardown(struct vbus_enet_priv *priv) +{ + if (!priv->evq.enabled) + return; + + ioq_put(priv->evq.veq.queue); + kfree(priv->evq.pool); +} + +/* + * Open and close + */ + +static int +vbus_enet_open(struct net_device *dev) +{ + struct vbus_enet_priv *priv = netdev_priv(dev); + int ret; + + ret = devcall(priv, VENET_FUNC_LINKUP, NULL, 0); + BUG_ON(ret < 0); + + napi_enable(&priv->napi); + + return 0; +} + +static int +vbus_enet_stop(struct net_device *dev) +{ + struct vbus_enet_priv *priv = netdev_priv(dev); + int ret; + + napi_disable(&priv->napi); + + ret = devcall(priv, VENET_FUNC_LINKDOWN, NULL, 0); + BUG_ON(ret < 0); + + return 0; +} + +/* + * Configuration changes (passed on by ifconfig) + */ +static int +vbus_enet_config(struct net_device *dev, struct ifmap *map) +{ + if (dev->flags & IFF_UP) /* can't act on a running interface */ + return -EBUSY; + + /* Don't allow changing the I/O address */ + if (map->base_addr != dev->base_addr) { + dev_warn(&dev->dev, "Can't change I/O address\n"); + return -EOPNOTSUPP; + } + + /* ignore other fields */ + return 0; +} + +static void +vbus_enet_schedule_rx(struct vbus_enet_priv *priv) +{ + unsigned long flags; + + spin_lock_irqsave(&priv->lock, flags); + + if (napi_schedule_prep(&priv->napi)) { + /* Disable further interrupts */ + ioq_notify_disable(priv->rxq.queue, 0); + __napi_schedule(&priv->napi); + } + + spin_unlock_irqrestore(&priv->lock, flags); +} + +static int +vbus_enet_change_mtu(struct net_device *dev, int new_mtu) +{ + struct vbus_enet_priv *priv = netdev_priv(dev); + int ret; + + dev->mtu = new_mtu; + + /* + * FLUSHRX will cause the device to flush any outstanding + * RX buffers. They will appear to come in as 0 length + * packets which we can simply discard and replace with new_mtu + * buffers for the future. + */ + ret = devcall(priv, VENET_FUNC_FLUSHRX, NULL, 0); + BUG_ON(ret < 0); + + vbus_enet_schedule_rx(priv); + + return 0; +} + +static struct sk_buff * +vbus_enet_l4ro_import(struct vbus_enet_priv *priv, struct ioq_ring_desc *desc) +{ + struct venet_sg *vsg = (struct venet_sg *)(unsigned long)desc->cookie; + struct sk_buff *skb = (struct sk_buff *)(unsigned long)vsg->cookie; + struct skb_shared_info *sinfo = skb_shinfo(skb); + int i; + + rx_pageq_refill(priv, GFP_ATOMIC); + + if (!vsg->len) + /* + * the device may send a zero-length packet when its + * flushing references on the ring. We can just drop + * these on the floor + */ + goto fail; + + /* advance only by the linear portion in IOV[0] */ + skb_put(skb, vsg->iov[0].len); + + /* skip i=0, since that is the skb->data IOV */ + for (i = 1; i < vsg->count; i++) { + struct venet_iov *iov = &vsg->iov[i]; + struct page *page = (struct page *)(unsigned long)iov->ptr; + skb_frag_t *f = &sinfo->frags[i-1]; + + f->page = page; + f->page_offset = 0; + f->size = iov->len; + + PDEBUG(priv->dev, "SG: Importing %d byte page[%i]\n", + f->size, i); + + skb->data_len += f->size; + skb->len += f->size; + skb->truesize += f->size; + sinfo->nr_frags++; + } + + if (vsg->flags & VENET_SG_FLAG_NEEDS_CSUM + && !skb_partial_csum_set(skb, vsg->csum.start, + vsg->csum.offset)) { + priv->dev->stats.rx_frame_errors++; + goto fail; + } + + if (vsg->flags & VENET_SG_FLAG_GSO) { + PDEBUG(priv->dev, "L4RO packet detected\n"); + + switch (vsg->gso.type) { + case VENET_GSO_TYPE_TCPV4: + sinfo->gso_type = SKB_GSO_TCPV4; + break; + case VENET_GSO_TYPE_TCPV6: + sinfo->gso_type = SKB_GSO_TCPV6; + break; + case VENET_GSO_TYPE_UDP: + sinfo->gso_type = SKB_GSO_UDP; + break; + default: + PDEBUG(priv->dev, "Illegal L4RO type: %d\n", + vsg->gso.type); + priv->dev->stats.rx_frame_errors++; + goto fail; + } + + if (vsg->flags & VENET_SG_FLAG_ECN) + sinfo->gso_type |= SKB_GSO_TCP_ECN; + + sinfo->gso_size = vsg->gso.size; + if (sinfo->gso_size == 0) { + PDEBUG(priv->dev, "Illegal L4RO size: %d\n", + vsg->gso.size); + priv->dev->stats.rx_frame_errors++; + goto fail; + } + + /* + * Header must be checked, and gso_segs + * computed. + */ + sinfo->gso_type |= SKB_GSO_DODGY; + sinfo->gso_segs = 0; + } + + return skb; + +fail: + dev_kfree_skb(skb); + + return NULL; +} + +static struct sk_buff * +vbus_enet_flat_import(struct vbus_enet_priv *priv, struct ioq_ring_desc *desc) +{ + struct sk_buff *skb = (struct sk_buff *)(unsigned long)desc->cookie; + + if (!desc->len) { + /* + * the device may send a zero-length packet when its + * flushing references on the ring. We can just drop + * these on the floor + */ + dev_kfree_skb(skb); + return NULL; + } + + skb_put(skb, le64_to_cpu(desc->len)); + + return skb; +} + +/* + * The poll implementation. + */ +static int +vbus_enet_poll(struct napi_struct *napi, int budget) +{ + struct vbus_enet_priv *priv = napi_to_priv(napi); + int npackets = 0; + struct ioq_iterator iter; + int ret; + + PDEBUG(priv->dev, "polling...\n"); + + /* We want to iterate on the head of the in-use index */ + ret = ioq_iter_init(priv->rxq.queue, &iter, ioq_idxtype_inuse, + IOQ_ITER_AUTOUPDATE); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_head, 0, 0); + BUG_ON(ret < 0); + + /* + * We stop if we have met the quota or there are no more packets. + * The EOM is indicated by finding a packet that is still owned by + * the south side + */ + while ((npackets < budget) && (!iter.desc->sown)) { + struct sk_buff *skb; + + skb = priv->import(priv, iter.desc); + if (skb) { + /* Maintain stats */ + npackets++; + priv->dev->stats.rx_packets++; + priv->dev->stats.rx_bytes += skb->len; + + /* Pass the buffer up to the stack */ + skb->dev = priv->dev; + skb->protocol = eth_type_trans(skb, priv->dev); + netif_receive_skb(skb); + + mb(); + } + + /* Grab a new buffer to put in the ring */ + rxdesc_alloc(priv, iter.desc, priv->dev->mtu); + + /* Advance the in-use tail */ + ret = ioq_iter_pop(&iter, 0); + BUG_ON(ret < 0); + } + + PDEBUG(priv->dev, "%d packets received\n", npackets); + + /* + * If we processed all packets, we're done; tell the kernel and + * reenable ints + */ + if (ioq_empty(priv->rxq.queue, ioq_idxtype_inuse)) { + napi_complete(napi); + ioq_notify_enable(priv->rxq.queue, 0); + ret = 0; + } else + /* We couldn't process everything. */ + ret = 1; + + return ret; +} + +/* + * Transmit a packet (called by the kernel) + */ +static int +vbus_enet_tx_start(struct sk_buff *skb, struct net_device *dev) +{ + struct vbus_enet_priv *priv = netdev_priv(dev); + struct ioq_iterator iter; + int ret; + unsigned long flags; + + PDEBUG(priv->dev, "sending %d bytes\n", skb->len); + + spin_lock_irqsave(&priv->lock, flags); + + if (ioq_full(priv->tx.veq.queue, ioq_idxtype_valid)) { + /* + * We must flow-control the kernel by disabling the + * queue + */ + spin_unlock_irqrestore(&priv->lock, flags); + netif_stop_queue(dev); + dev_err(&priv->dev->dev, "tx on full queue bug\n"); + return 1; + } + + /* + * We want to iterate on the tail of both the "inuse" and "valid" index + * so we specify the "both" index + */ + ret = ioq_iter_init(priv->tx.veq.queue, &iter, ioq_idxtype_both, + IOQ_ITER_AUTOUPDATE); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_tail, 0, 0); + BUG_ON(ret < 0); + BUG_ON(iter.desc->sown); + + if (priv->sg) { + struct venet_sg *vsg = (struct venet_sg *)(unsigned long)iter.desc->cookie; + struct scatterlist sgl[MAX_SKB_FRAGS+1]; + struct scatterlist *sg; + int count, maxcount = ARRAY_SIZE(sgl); + + sg_init_table(sgl, maxcount); + + memset(vsg, 0, sizeof(*vsg)); + + vsg->cookie = (u64)(unsigned long)skb; + vsg->len = skb->len; + + if (skb->ip_summed == CHECKSUM_PARTIAL) { + vsg->flags |= VENET_SG_FLAG_NEEDS_CSUM; + vsg->csum.start = skb->csum_start - skb_headroom(skb); + vsg->csum.offset = skb->csum_offset; + } + + if (skb_is_gso(skb)) { + struct skb_shared_info *sinfo = skb_shinfo(skb); + + vsg->flags |= VENET_SG_FLAG_GSO; + + vsg->gso.hdrlen = skb_headlen(skb); + vsg->gso.size = sinfo->gso_size; + if (sinfo->gso_type & SKB_GSO_TCPV4) + vsg->gso.type = VENET_GSO_TYPE_TCPV4; + else if (sinfo->gso_type & SKB_GSO_TCPV6) + vsg->gso.type = VENET_GSO_TYPE_TCPV6; + else if (sinfo->gso_type & SKB_GSO_UDP) + vsg->gso.type = VENET_GSO_TYPE_UDP; + else + panic("Virtual-Ethernet: unknown GSO type " \ + "0x%x\n", sinfo->gso_type); + + if (sinfo->gso_type & SKB_GSO_TCP_ECN) + vsg->flags |= VENET_SG_FLAG_ECN; + } + + count = skb_to_sgvec(skb, sgl, 0, skb->len); + + BUG_ON(count > maxcount); + + for (sg = &sgl[0]; sg; sg = sg_next(sg)) { + struct venet_iov *iov = &vsg->iov[vsg->count++]; + + iov->len = sg->length; + iov->ptr = (u64)sg_phys(sg); + } + + iter.desc->len = cpu_to_le64(VSG_DESC_SIZE(vsg->count)); + + } else { + /* + * non scatter-gather mode: simply put the skb right onto the + * ring. + */ + iter.desc->cookie = (u64)(unsigned long)skb; + iter.desc->len = cpu_to_le64(skb->len); + iter.desc->ptr = cpu_to_le64(__pa(skb->data)); + } + + iter.desc->valid = 1; + + priv->dev->stats.tx_packets++; + priv->dev->stats.tx_bytes += skb->len; + + skb_queue_tail(&priv->tx.outstanding, skb); + + /* + * This advances both indexes together implicitly, and then + * signals the south side to consume the packet + */ + ret = ioq_iter_push(&iter, 0); + BUG_ON(ret < 0); + + dev->trans_start = jiffies; /* save the timestamp */ + + if (ioq_full(priv->tx.veq.queue, ioq_idxtype_valid)) { + /* + * If the queue is congested, we must flow-control the kernel + */ + PDEBUG(priv->dev, "backpressure tx queue\n"); + netif_stop_queue(dev); + } + + spin_unlock_irqrestore(&priv->lock, flags); + + return 0; +} + +/* assumes priv->lock held */ +static void +vbus_enet_skb_complete(struct vbus_enet_priv *priv, struct sk_buff *skb) +{ + PDEBUG(priv->dev, "completed sending %d bytes\n", + skb->len); + + skb_unlink(skb, &priv->tx.outstanding); + dev_kfree_skb(skb); +} + +/* + * reclaim any outstanding completed tx packets + * + * assumes priv->lock held + */ +static struct sk_buff * +vbus_enet_tx_reap_one(struct vbus_enet_priv *priv) +{ + struct sk_buff *skb = NULL; + struct ioq_iterator iter; + unsigned long flags; + int ret; + + spin_lock_irqsave(&priv->lock, flags); + + /* + * We want to iterate on the head of the valid index, but we + * do not want the iter_pop (below) to flip the ownership, so + * we set the NOFLIPOWNER option + */ + ret = ioq_iter_init(priv->tx.veq.queue, &iter, ioq_idxtype_valid, + IOQ_ITER_NOFLIPOWNER); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_head, 0, 0); + BUG_ON(ret < 0); + + if (iter.desc->valid && !iter.desc->sown) { + + if (priv->sg) { + struct venet_sg *vsg; + + vsg = (struct venet_sg *)(unsigned long)iter.desc->cookie; + skb = (struct sk_buff *)(unsigned long)vsg->cookie; + } else + skb = (struct sk_buff *)(unsigned long)iter.desc->cookie; + + /* Reset the descriptor */ + iter.desc->valid = 0; + + /* Advance the valid-index head */ + ret = ioq_iter_pop(&iter, 0); + BUG_ON(ret < 0); + } + + /* + * If we were previously stopped due to flow control, restart the + * processing + */ + if (netif_queue_stopped(priv->dev) + && !ioq_full(priv->tx.veq.queue, ioq_idxtype_valid)) { + PDEBUG(priv->dev, "re-enabling tx queue\n"); + netif_wake_queue(priv->dev); + } + + spin_unlock_irqrestore(&priv->lock, flags); + + return skb; +} + +static void +vbus_enet_tx_reap(struct vbus_enet_priv *priv) +{ + struct sk_buff *skb; + + while ((skb = vbus_enet_tx_reap_one(priv))) { + if (!priv->evq.txc) + /* + * We are responsible for freeing the packet upon + * reap if TXC is not enabled + */ + vbus_enet_skb_complete(priv, skb); + } +} + +static void +vbus_enet_timeout(struct net_device *dev) +{ + struct vbus_enet_priv *priv = netdev_priv(dev); + + dev_dbg(&dev->dev, "Transmit timeout\n"); + + vbus_enet_tx_reap(priv); +} + +static void +rx_isr(struct ioq_notifier *notifier) +{ + struct vbus_enet_priv *priv; + struct net_device *dev; + + priv = container_of(notifier, struct vbus_enet_priv, rxq.notifier); + dev = priv->dev; + + if (!ioq_empty(priv->rxq.queue, ioq_idxtype_inuse)) + vbus_enet_schedule_rx(priv); +} + +static void +deferred_tx_isr(unsigned long data) +{ + struct vbus_enet_priv *priv = (struct vbus_enet_priv *)data; + + PDEBUG(priv->dev, "deferred_tx_isr\n"); + + vbus_enet_tx_reap(priv); + + ioq_notify_enable(priv->tx.veq.queue, 0); +} + +static void +tx_isr(struct ioq_notifier *notifier) +{ + struct vbus_enet_priv *priv; + + priv = container_of(notifier, struct vbus_enet_priv, tx.veq.notifier); + + PDEBUG(priv->dev, "tx_isr\n"); + + ioq_notify_disable(priv->tx.veq.queue, 0); + tasklet_schedule(&priv->tx.task); +} + +static void +evq_linkstate_event(struct vbus_enet_priv *priv, + struct venet_event_header *header) +{ + struct venet_event_linkstate *event = + (struct venet_event_linkstate *)header; + + switch (event->state) { + case 0: + netif_carrier_off(priv->dev); + break; + case 1: + netif_carrier_on(priv->dev); + break; + default: + break; + } +} + +static void +evq_txc_event(struct vbus_enet_priv *priv, + struct venet_event_header *header) +{ + struct venet_event_txc *event = + (struct venet_event_txc *)header; + + vbus_enet_tx_reap(priv); + + vbus_enet_skb_complete(priv, (struct sk_buff *)(unsigned long)event->cookie); +} + +static void +deferred_evq_isr(unsigned long data) +{ + struct vbus_enet_priv *priv = (struct vbus_enet_priv *)data; + int nevents = 0; + struct ioq_iterator iter; + int ret; + + PDEBUG(priv->dev, "evq: polling...\n"); + + /* We want to iterate on the head of the in-use index */ + ret = ioq_iter_init(priv->evq.veq.queue, &iter, ioq_idxtype_inuse, + IOQ_ITER_AUTOUPDATE); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_head, 0, 0); + BUG_ON(ret < 0); + + /* + * The EOM is indicated by finding a packet that is still owned by + * the south side + */ + while (!iter.desc->sown) { + struct venet_event_header *header; + + header = (struct venet_event_header *)(unsigned long)iter.desc->cookie; + + switch (header->id) { + case VENET_EVENT_LINKSTATE: + evq_linkstate_event(priv, header); + break; + case VENET_EVENT_TXC: + evq_txc_event(priv, header); + break; + default: + panic("venet: unexpected event id:%d of size %d\n", + header->id, header->size); + break; + } + + memset((void *)(unsigned long)iter.desc->cookie, 0, priv->evq.evsize); + + /* Advance the in-use tail */ + ret = ioq_iter_pop(&iter, 0); + BUG_ON(ret < 0); + + nevents++; + } + + PDEBUG(priv->dev, "%d events received\n", nevents); + + ioq_notify_enable(priv->evq.veq.queue, 0); +} + +static void +evq_isr(struct ioq_notifier *notifier) +{ + struct vbus_enet_priv *priv; + + priv = container_of(notifier, struct vbus_enet_priv, evq.veq.notifier); + + PDEBUG(priv->dev, "evq_isr\n"); + + ioq_notify_disable(priv->evq.veq.queue, 0); + tasklet_schedule(&priv->evq.task); +} + +static int +vbus_enet_sg_negcap(struct vbus_enet_priv *priv) +{ + struct net_device *dev = priv->dev; + struct venet_capabilities caps; + int ret; + + memset(&caps, 0, sizeof(caps)); + + if (sg_enabled) { + caps.gid = VENET_CAP_GROUP_SG; + caps.bits |= (VENET_CAP_SG|VENET_CAP_TSO4|VENET_CAP_TSO6 + |VENET_CAP_ECN|VENET_CAP_PMTD); + /* note: exclude UFO for now due to stack bug */ + } + + ret = devcall(priv, VENET_FUNC_NEGCAP, &caps, sizeof(caps)); + if (ret < 0) + return ret; + + if (caps.bits & VENET_CAP_SG) { + priv->sg = true; + + dev->features |= NETIF_F_SG|NETIF_F_HW_CSUM|NETIF_F_FRAGLIST; + + if (caps.bits & VENET_CAP_TSO4) + dev->features |= NETIF_F_TSO; + if (caps.bits & VENET_CAP_UFO) + dev->features |= NETIF_F_UFO; + if (caps.bits & VENET_CAP_TSO6) + dev->features |= NETIF_F_TSO6; + if (caps.bits & VENET_CAP_ECN) + dev->features |= NETIF_F_TSO_ECN; + + if (caps.bits & VENET_CAP_PMTD) + priv->pmtd.enabled = true; + } + + return 0; +} + +static int +vbus_enet_evq_negcap(struct vbus_enet_priv *priv, unsigned long count) +{ + struct venet_capabilities caps; + int ret; + + memset(&caps, 0, sizeof(caps)); + + caps.gid = VENET_CAP_GROUP_EVENTQ; + caps.bits |= VENET_CAP_EVQ_LINKSTATE; + caps.bits |= VENET_CAP_EVQ_TXC; + + ret = devcall(priv, VENET_FUNC_NEGCAP, &caps, sizeof(caps)); + if (ret < 0) + return ret; + + if (caps.bits) { + struct vbus_device_proxy *dev = priv->vdev; + struct venet_eventq_query query; + size_t poollen; + struct ioq_iterator iter; + char *pool; + int i; + + priv->evq.enabled = true; + + if (caps.bits & VENET_CAP_EVQ_LINKSTATE) { + /* + * We will assume there is no carrier until we get + * an event telling us otherwise + */ + netif_carrier_off(priv->dev); + priv->evq.linkstate = true; + } + + if (caps.bits & VENET_CAP_EVQ_TXC) + priv->evq.txc = true; + + memset(&query, 0, sizeof(query)); + + ret = devcall(priv, VENET_FUNC_EVQQUERY, &query, sizeof(query)); + if (ret < 0) + return ret; + + priv->evq.evsize = query.evsize; + poollen = query.evsize * count; + + pool = kzalloc(poollen, GFP_KERNEL | GFP_DMA); + if (!pool) + return -ENOMEM; + + priv->evq.pool = pool; + + ret = dev->ops->shm(dev, NULL, query.dpid, 0, + pool, poollen, NULL, NULL, 0); + if (ret < 0) + return ret; + + queue_init(priv, &priv->evq.veq, "evq", + query.qid, count, evq_isr); + + ret = ioq_iter_init(priv->evq.veq.queue, + &iter, ioq_idxtype_valid, 0); + BUG_ON(ret < 0); + + ret = ioq_iter_seek(&iter, ioq_seek_set, 0, 0); + BUG_ON(ret < 0); + + /* Now populate each descriptor with an empty event */ + for (i = 0; i < count; i++) { + size_t offset = (i * query.evsize); + void *addr = &priv->evq.pool[offset]; + + iter.desc->ptr = cpu_to_le64(offset); + iter.desc->cookie = (u64)(unsigned long)addr; + iter.desc->len = cpu_to_le64(query.evsize); + + ret = ioq_iter_push(&iter, 0); + BUG_ON(ret < 0); + } + + /* Finally, enable interrupts */ + tasklet_init(&priv->evq.task, deferred_evq_isr, + (unsigned long)priv); + ioq_notify_enable(priv->evq.veq.queue, 0); + } + + return 0; +} + +static int +vbus_enet_l4ro_negcap(struct vbus_enet_priv *priv, unsigned long count) +{ + struct venet_capabilities caps; + int ret; + + memset(&caps, 0, sizeof(caps)); + + caps.gid = VENET_CAP_GROUP_L4RO; + caps.bits |= (VENET_CAP_SG|VENET_CAP_TSO4|VENET_CAP_TSO6 + |VENET_CAP_ECN); + + ret = devcall(priv, VENET_FUNC_NEGCAP, &caps, sizeof(caps)); + if (ret < 0) { + printk(KERN_ERR "Error negotiating L4RO: %d\n", ret); + return ret; + } + + if (caps.bits & VENET_CAP_SG) { + struct vbus_device_proxy *dev = priv->vdev; + size_t poollen = SG_DESC_SIZE * count; + struct venet_l4ro_query query; + char *pool; + + memset(&query, 0, sizeof(query)); + + ret = devcall(priv, VENET_FUNC_L4ROQUERY, &query, sizeof(query)); + if (ret < 0) { + printk(KERN_ERR "Error querying L4RO: %d\n", ret); + return ret; + } + + pool = kzalloc(poollen, GFP_KERNEL | GFP_DMA); + if (!pool) + return -ENOMEM; + + /* + * pre-mapped descriptor pool + */ + ret = dev->ops->shm(dev, NULL, query.dpid, 0, + pool, poollen, NULL, NULL, 0); + if (ret < 0) { + printk(KERN_ERR "Error registering L4RO pool: %d\n", + ret); + kfree(pool); + return ret; + } + + /* + * page-queue: contains a ring of arbitrary pages for + * consumption by the host for when the SG::IOV count exceeds + * one MTU frame. All we need to do is keep it populated + * with free pages. + */ + queue_init(priv, &priv->l4ro.pageq, "pageq", query.pqid, + count, NULL); + + priv->l4ro.pool = pool; + priv->l4ro.available = true; + } + + return 0; +} + +static int +vbus_enet_negcap(struct vbus_enet_priv *priv) +{ + int ret; + + ret = vbus_enet_sg_negcap(priv); + if (ret < 0) + return ret; + + ret = vbus_enet_evq_negcap(priv, tx_ringlen); + if (ret < 0) + return ret; + + ret = vbus_enet_l4ro_negcap(priv, rx_ringlen); + if (ret < 0) + return ret; + + return 0; +} + +static int vbus_enet_set_tx_csum(struct net_device *dev, u32 data) +{ + struct vbus_enet_priv *priv = netdev_priv(dev); + + if (data && !priv->sg) + return -ENOSYS; + + return ethtool_op_set_tx_hw_csum(dev, data); +} + +static struct ethtool_ops vbus_enet_ethtool_ops = { + .set_tx_csum = vbus_enet_set_tx_csum, + .set_sg = ethtool_op_set_sg, + .set_tso = ethtool_op_set_tso, + .get_link = ethtool_op_get_link, +}; + +static const struct net_device_ops vbus_enet_netdev_ops = { + .ndo_open = vbus_enet_open, + .ndo_stop = vbus_enet_stop, + .ndo_set_config = vbus_enet_config, + .ndo_start_xmit = vbus_enet_tx_start, + .ndo_change_mtu = vbus_enet_change_mtu, + .ndo_tx_timeout = vbus_enet_timeout, + .ndo_set_mac_address = eth_mac_addr, + .ndo_validate_addr = eth_validate_addr, +}; + +/* + * This is called whenever a new vbus_device_proxy is added to the vbus + * with the matching VENET_ID + */ +static int +vbus_enet_probe(struct vbus_device_proxy *vdev) +{ + struct net_device *dev; + struct vbus_enet_priv *priv; + int ret; + + printk(KERN_INFO "VENET: Found new device at %lld\n", vdev->id); + + ret = vdev->ops->open(vdev, VENET_VERSION, 0); + if (ret < 0) + return ret; + + dev = alloc_etherdev(sizeof(struct vbus_enet_priv)); + if (!dev) + return -ENOMEM; + + /* + * establish our device-name early so we can incorporate it into + * the signal-path names, etc + */ + rtnl_lock(); + + ret = dev_alloc_name(dev, dev->name); + if (ret < 0) + goto out_free; + + priv = netdev_priv(dev); + + spin_lock_init(&priv->lock); + priv->dev = dev; + priv->vdev = vdev; + + ret = vbus_enet_negcap(priv); + if (ret < 0) { + printk(KERN_INFO "VENET: Error negotiating capabilities for " \ + "%lld\n", + priv->vdev->id); + goto out_free; + } + + if (priv->l4ro.available) + priv->import = &vbus_enet_l4ro_import; + else + priv->import = &vbus_enet_flat_import; + + skb_queue_head_init(&priv->tx.outstanding); + + queue_init(priv, &priv->rxq, "rx", VENET_QUEUE_RX, rx_ringlen, + rx_isr); + queue_init(priv, &priv->tx.veq, "tx", VENET_QUEUE_TX, tx_ringlen, + tx_isr); + + rx_setup(priv); + tx_setup(priv); + + ioq_notify_enable(priv->rxq.queue, 0); /* enable rx interrupts */ + + if (!priv->evq.txc) { + /* + * If the TXC feature is present, we will recieve our + * tx-complete notification via the event-channel. Therefore, + * we only enable txq interrupts if the TXC feature is not + * present. + */ + tasklet_init(&priv->tx.task, deferred_tx_isr, + (unsigned long)priv); + ioq_notify_enable(priv->tx.veq.queue, 0); + } + + dev->netdev_ops = &vbus_enet_netdev_ops; + dev->watchdog_timeo = 5 * HZ; + SET_ETHTOOL_OPS(dev, &vbus_enet_ethtool_ops); + SET_NETDEV_DEV(dev, &vdev->dev); + + netif_napi_add(dev, &priv->napi, vbus_enet_poll, 128); + + ret = devcall(priv, VENET_FUNC_MACQUERY, priv->dev->dev_addr, ETH_ALEN); + if (ret < 0) { + printk(KERN_INFO "VENET: Error obtaining MAC address for " \ + "%lld\n", + priv->vdev->id); + goto out_free; + } + + dev->features |= NETIF_F_HIGHDMA; + + ret = register_netdevice(dev); + if (ret < 0) { + printk(KERN_INFO "VENET: error %i registering device \"%s\"\n", + ret, dev->name); + goto out_free; + } + + rtnl_unlock(); + + vdev->priv = priv; + + return 0; + + out_free: + rtnl_unlock(); + + free_netdev(dev); + + return ret; +} + +static int +vbus_enet_remove(struct vbus_device_proxy *vdev) +{ + struct vbus_enet_priv *priv = (struct vbus_enet_priv *)vdev->priv; + struct vbus_device_proxy *dev = priv->vdev; + + unregister_netdev(priv->dev); + napi_disable(&priv->napi); + + rx_teardown(priv); + ioq_put(priv->rxq.queue); + + tx_teardown(priv); + ioq_put(priv->tx.veq.queue); + + if (priv->evq.enabled) + evq_teardown(priv); + + dev->ops->close(dev, 0); + + free_netdev(priv->dev); + + return 0; +} + +/* + * Finally, the module stuff + */ + +static struct vbus_driver_ops vbus_enet_driver_ops = { + .probe = vbus_enet_probe, + .remove = vbus_enet_remove, +}; + +static struct vbus_driver vbus_enet_driver = { + .type = VENET_TYPE, + .owner = THIS_MODULE, + .ops = &vbus_enet_driver_ops, +}; + +static __init int +vbus_enet_init_module(void) +{ + printk(KERN_INFO "Virtual Ethernet: Copyright (C) 2009 Novell, Gregory Haskins\n"); + printk(KERN_DEBUG "VENET: Using %d/%d queue depth\n", + rx_ringlen, tx_ringlen); + return vbus_driver_register(&vbus_enet_driver); +} + +static __exit void +vbus_enet_cleanup(void) +{ + vbus_driver_unregister(&vbus_enet_driver); +} + +module_init(vbus_enet_init_module); +module_exit(vbus_enet_cleanup); + +VBUS_DRIVER_AUTOPROBE(VENET_TYPE); |