--- /dev/null
+/******************************************************************************
+ * arch/xen/drivers/netif/backend/interface.c
+ *
+ * Network-device interface management.
+ *
+ * Copyright (c) 2004-2005, Keir Fraser
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "common.h"
+#include <linux/ethtool.h>
+#include <linux/rtnetlink.h>
+
+/*
+ * Module parameter 'queue_length':
+ *
+ * Enables queuing in the network stack when a client has run out of receive
+ * descriptors. Although this feature can improve receive bandwidth by avoiding
+ * packet loss, it can also result in packets sitting in the 'tx_queue' for
+ * unbounded time. This is bad if those packets hold onto foreign resources.
+ * For example, consider a packet that holds onto resources belonging to the
+ * guest for which it is queued (e.g., packet received on vif1.0, destined for
+ * vif1.1 which is not activated in the guest): in this situation the guest
+ * will never be destroyed, unless vif1.1 is taken down. To avoid this, we
+ * run a timer (tx_queue_timeout) to drain the queue when the interface is
+ * blocked.
+ */
+static unsigned long netbk_queue_length = 32;
+module_param_named(queue_length, netbk_queue_length, ulong, 0);
+
+static void __netif_up(netif_t *netif)
+{
+ enable_irq(netif->irq);
+ netif_schedule_work(netif);
+}
+
+static void __netif_down(netif_t *netif)
+{
+ disable_irq(netif->irq);
+ netif_deschedule_work(netif);
+}
+
+static int net_open(struct net_device *dev)
+{
+ netif_t *netif = netdev_priv(dev);
+ if (netback_carrier_ok(netif)) {
+ __netif_up(netif);
+ netif_start_queue(dev);
+ }
+ return 0;
+}
+
+static int net_close(struct net_device *dev)
+{
+ netif_t *netif = netdev_priv(dev);
+ if (netback_carrier_ok(netif))
+ __netif_down(netif);
+ netif_stop_queue(dev);
+ return 0;
+}
+
+static int netbk_change_mtu(struct net_device *dev, int mtu)
+{
+ int max = netbk_can_sg(dev) ? 65535 - ETH_HLEN : ETH_DATA_LEN;
+
+ if (mtu > max)
+ return -EINVAL;
+ dev->mtu = mtu;
+ return 0;
+}
+
+static int netbk_set_sg(struct net_device *dev, u32 data)
+{
+ if (data) {
+ netif_t *netif = netdev_priv(dev);
+
+ if (!(netif->features & NETIF_F_SG))
+ return -ENOSYS;
+ }
+
+ return ethtool_op_set_sg(dev, data);
+}
+
+static int netbk_set_tso(struct net_device *dev, u32 data)
+{
+ if (data) {
+ netif_t *netif = netdev_priv(dev);
+
+ if (!(netif->features & NETIF_F_TSO))
+ return -ENOSYS;
+ }
+
+ return ethtool_op_set_tso(dev, data);
+}
+
+static struct ethtool_ops network_ethtool_ops =
+{
+ .get_tx_csum = ethtool_op_get_tx_csum,
+ .set_tx_csum = ethtool_op_set_tx_csum,
+ .get_sg = ethtool_op_get_sg,
+ .set_sg = netbk_set_sg,
+ .get_tso = ethtool_op_get_tso,
+ .set_tso = netbk_set_tso,
+ .get_link = ethtool_op_get_link,
+};
+
+netif_t *netif_alloc(domid_t domid, unsigned int handle)
+{
+ int err = 0;
+ struct net_device *dev;
+ netif_t *netif;
+ char name[IFNAMSIZ] = {};
+
+ snprintf(name, IFNAMSIZ - 1, "vif%u.%u", domid, handle);
+ dev = alloc_netdev(sizeof(netif_t), name, ether_setup);
+ if (dev == NULL) {
+ DPRINTK("Could not create netif: out of memory\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ netif = netdev_priv(dev);
+ memset(netif, 0, sizeof(*netif));
+ netif->domid = domid;
+ netif->handle = handle;
+ atomic_set(&netif->refcnt, 1);
+ init_waitqueue_head(&netif->waiting_to_free);
+ netif->dev = dev;
+
+ netback_carrier_off(netif);
+
+ netif->credit_bytes = netif->remaining_credit = ~0UL;
+ netif->credit_usec = 0UL;
+ init_timer(&netif->credit_timeout);
+ /* Initialize 'expires' now: it's used to track the credit window. */
+ netif->credit_timeout.expires = jiffies;
+
+ init_timer(&netif->tx_queue_timeout);
+
+ dev->hard_start_xmit = netif_be_start_xmit;
+ dev->get_stats = netif_be_get_stats;
+ dev->open = net_open;
+ dev->stop = net_close;
+ dev->change_mtu = netbk_change_mtu;
+ dev->features = NETIF_F_IP_CSUM;
+
+ SET_ETHTOOL_OPS(dev, &network_ethtool_ops);
+
+ dev->tx_queue_len = netbk_queue_length;
+
+ /*
+ * Initialise a dummy MAC address. We choose the numerically
+ * largest non-broadcast address to prevent the address getting
+ * stolen by an Ethernet bridge for STP purposes.
+ * (FE:FF:FF:FF:FF:FF)
+ */
+ memset(dev->dev_addr, 0xFF, ETH_ALEN);
+ dev->dev_addr[0] &= ~0x01;
+
+ rtnl_lock();
+ err = register_netdevice(dev);
+ rtnl_unlock();
+ if (err) {
+ DPRINTK("Could not register new net device %s: err=%d\n",
+ dev->name, err);
+ free_netdev(dev);
+ return ERR_PTR(err);
+ }
+
+ DPRINTK("Successfully created netif\n");
+ return netif;
+}
+
+static int map_frontend_pages(
+ netif_t *netif, grant_ref_t tx_ring_ref, grant_ref_t rx_ring_ref)
+{
+ struct gnttab_map_grant_ref op;
+
+ gnttab_set_map_op(&op, (unsigned long)netif->tx_comms_area->addr,
+ GNTMAP_host_map, tx_ring_ref, netif->domid);
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
+ BUG();
+
+ if (op.status) {
+ DPRINTK(" Gnttab failure mapping tx_ring_ref!\n");
+ return op.status;
+ }
+
+ netif->tx_shmem_ref = tx_ring_ref;
+ netif->tx_shmem_handle = op.handle;
+
+ gnttab_set_map_op(&op, (unsigned long)netif->rx_comms_area->addr,
+ GNTMAP_host_map, rx_ring_ref, netif->domid);
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
+ BUG();
+
+ if (op.status) {
+ DPRINTK(" Gnttab failure mapping rx_ring_ref!\n");
+ return op.status;
+ }
+
+ netif->rx_shmem_ref = rx_ring_ref;
+ netif->rx_shmem_handle = op.handle;
+
+ return 0;
+}
+
+static void unmap_frontend_pages(netif_t *netif)
+{
+ struct gnttab_unmap_grant_ref op;
+
+ gnttab_set_unmap_op(&op, (unsigned long)netif->tx_comms_area->addr,
+ GNTMAP_host_map, netif->tx_shmem_handle);
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
+ BUG();
+
+ gnttab_set_unmap_op(&op, (unsigned long)netif->rx_comms_area->addr,
+ GNTMAP_host_map, netif->rx_shmem_handle);
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
+ BUG();
+}
+
+int netif_map(netif_t *netif, unsigned long tx_ring_ref,
+ unsigned long rx_ring_ref, unsigned int evtchn)
+{
+ int err = -ENOMEM;
+ netif_tx_sring_t *txs;
+ netif_rx_sring_t *rxs;
+
+ /* Already connected through? */
+ if (netif->irq)
+ return 0;
+
+ netif->tx_comms_area = alloc_vm_area(PAGE_SIZE);
+ if (netif->tx_comms_area == NULL)
+ return -ENOMEM;
+ netif->rx_comms_area = alloc_vm_area(PAGE_SIZE);
+ if (netif->rx_comms_area == NULL)
+ goto err_rx;
+
+ err = map_frontend_pages(netif, tx_ring_ref, rx_ring_ref);
+ if (err)
+ goto err_map;
+
+ err = bind_interdomain_evtchn_to_irqhandler(
+ netif->domid, evtchn, netif_be_int, 0,
+ netif->dev->name, netif);
+ if (err < 0)
+ goto err_hypervisor;
+ netif->irq = err;
+ disable_irq(netif->irq);
+
+ txs = (netif_tx_sring_t *)netif->tx_comms_area->addr;
+ BACK_RING_INIT(&netif->tx, txs, PAGE_SIZE);
+
+ rxs = (netif_rx_sring_t *)
+ ((char *)netif->rx_comms_area->addr);
+ BACK_RING_INIT(&netif->rx, rxs, PAGE_SIZE);
+
+ netif->rx_req_cons_peek = 0;
+
+ netif_get(netif);
+
+ rtnl_lock();
+ netback_carrier_on(netif);
+ if (netif_running(netif->dev))
+ __netif_up(netif);
+ rtnl_unlock();
+
+ return 0;
+err_hypervisor:
+ unmap_frontend_pages(netif);
+err_map:
+ free_vm_area(netif->rx_comms_area);
+err_rx:
+ free_vm_area(netif->tx_comms_area);
+ return err;
+}
+
+void netif_disconnect(netif_t *netif)
+{
+ if (netback_carrier_ok(netif)) {
+ rtnl_lock();
+ netback_carrier_off(netif);
+ netif_carrier_off(netif->dev); /* discard queued packets */
+ if (netif_running(netif->dev))
+ __netif_down(netif);
+ rtnl_unlock();
+ netif_put(netif);
+ }
+
+ atomic_dec(&netif->refcnt);
+ wait_event(netif->waiting_to_free, atomic_read(&netif->refcnt) == 0);
+
+ del_timer_sync(&netif->credit_timeout);
+ del_timer_sync(&netif->tx_queue_timeout);
+
+ if (netif->irq)
+ unbind_from_irqhandler(netif->irq, netif);
+
+ unregister_netdev(netif->dev);
+
+ if (netif->tx.sring) {
+ unmap_frontend_pages(netif);
+ free_vm_area(netif->tx_comms_area);
+ free_vm_area(netif->rx_comms_area);
+ }
+
+ free_netdev(netif->dev);
+}
--- /dev/null
+/******************************************************************************
+ * drivers/xen/netback/netback.c
+ *
+ * Back-end of the driver for virtual network devices. This portion of the
+ * driver exports a 'unified' network-device interface that can be accessed
+ * by any operating system that implements a compatible front end. A
+ * reference front-end implementation can be found in:
+ * drivers/xen/netfront/netfront.c
+ *
+ * Copyright (c) 2002-2005, K A Fraser
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "common.h"
+#include <xen/balloon.h>
+#include <xen/interface/memory.h>
+
+/*define NETBE_DEBUG_INTERRUPT*/
+
+struct netbk_rx_meta {
+ skb_frag_t frag;
+ int id;
+ u8 copy:1;
+};
+
+struct netbk_tx_pending_inuse {
+ struct list_head list;
+ unsigned long alloc_time;
+};
+
+static void netif_idx_release(u16 pending_idx);
+static void make_tx_response(netif_t *netif,
+ netif_tx_request_t *txp,
+ s8 st);
+static netif_rx_response_t *make_rx_response(netif_t *netif,
+ u16 id,
+ s8 st,
+ u16 offset,
+ u16 size,
+ u16 flags);
+
+static void net_tx_action(unsigned long unused);
+static DECLARE_TASKLET(net_tx_tasklet, net_tx_action, 0);
+
+static void net_rx_action(unsigned long unused);
+static DECLARE_TASKLET(net_rx_tasklet, net_rx_action, 0);
+
+static struct timer_list net_timer;
+static struct timer_list netbk_tx_pending_timer;
+
+#define MAX_PENDING_REQS 256
+
+static struct sk_buff_head rx_queue;
+
+static struct page **mmap_pages;
+static inline unsigned long idx_to_pfn(unsigned int idx)
+{
+ return page_to_pfn(mmap_pages[idx]);
+}
+
+static inline unsigned long idx_to_kaddr(unsigned int idx)
+{
+ return (unsigned long)pfn_to_kaddr(idx_to_pfn(idx));
+}
+
+/* extra field used in struct page */
+static inline void netif_set_page_index(struct page *pg, unsigned int index)
+{
+ *(unsigned long *)&pg->mapping = index;
+}
+
+static inline int netif_page_index(struct page *pg)
+{
+ unsigned long idx = (unsigned long)pg->mapping;
+
+ if (!PageForeign(pg))
+ return -1;
+
+ if ((idx >= MAX_PENDING_REQS) || (mmap_pages[idx] != pg))
+ return -1;
+
+ return idx;
+}
+
+#define PKT_PROT_LEN 64
+
+static struct pending_tx_info {
+ netif_tx_request_t req;
+ netif_t *netif;
+} pending_tx_info[MAX_PENDING_REQS];
+static u16 pending_ring[MAX_PENDING_REQS];
+typedef unsigned int PEND_RING_IDX;
+#define MASK_PEND_IDX(_i) ((_i)&(MAX_PENDING_REQS-1))
+static PEND_RING_IDX pending_prod, pending_cons;
+#define NR_PENDING_REQS (MAX_PENDING_REQS - pending_prod + pending_cons)
+
+/* Freed TX SKBs get batched on this ring before return to pending_ring. */
+static u16 dealloc_ring[MAX_PENDING_REQS];
+static PEND_RING_IDX dealloc_prod, dealloc_cons;
+
+/* Doubly-linked list of in-use pending entries. */
+static struct netbk_tx_pending_inuse pending_inuse[MAX_PENDING_REQS];
+static LIST_HEAD(pending_inuse_head);
+
+static struct sk_buff_head tx_queue;
+
+static grant_handle_t grant_tx_handle[MAX_PENDING_REQS];
+static gnttab_unmap_grant_ref_t tx_unmap_ops[MAX_PENDING_REQS];
+static gnttab_map_grant_ref_t tx_map_ops[MAX_PENDING_REQS];
+
+static struct list_head net_schedule_list;
+static spinlock_t net_schedule_list_lock;
+
+#define MAX_MFN_ALLOC 64
+static unsigned long mfn_list[MAX_MFN_ALLOC];
+static unsigned int alloc_index = 0;
+
+/* Setting this allows the safe use of this driver without netloop. */
+static int MODPARM_copy_skb = 1;
+module_param_named(copy_skb, MODPARM_copy_skb, bool, 0);
+MODULE_PARM_DESC(copy_skb, "Copy data received from netfront without netloop");
+
+int netbk_copy_skb_mode;
+
+static inline unsigned long alloc_mfn(void)
+{
+ BUG_ON(alloc_index == 0);
+ return mfn_list[--alloc_index];
+}
+
+static int check_mfn(int nr)
+{
+ struct xen_memory_reservation reservation = {
+ .extent_order = 0,
+ .domid = DOMID_SELF
+ };
+ int rc;
+
+ if (likely(alloc_index >= nr))
+ return 0;
+
+ set_xen_guest_handle(reservation.extent_start, mfn_list + alloc_index);
+ reservation.nr_extents = MAX_MFN_ALLOC - alloc_index;
+ rc = HYPERVISOR_memory_op(XENMEM_increase_reservation, &reservation);
+ if (likely(rc > 0))
+ alloc_index += rc;
+
+ return alloc_index >= nr ? 0 : -ENOMEM;
+}
+
+static inline void maybe_schedule_tx_action(void)
+{
+ smp_mb();
+ if ((NR_PENDING_REQS < (MAX_PENDING_REQS/2)) &&
+ !list_empty(&net_schedule_list))
+ tasklet_schedule(&net_tx_tasklet);
+}
+
+static struct sk_buff *netbk_copy_skb(struct sk_buff *skb)
+{
+ struct skb_shared_info *ninfo;
+ struct sk_buff *nskb;
+ unsigned long offset;
+ int ret;
+ int len;
+ int headlen;
+
+ BUG_ON(skb_shinfo(skb)->frag_list != NULL);
+
+ nskb = alloc_skb(SKB_MAX_HEAD(0), GFP_ATOMIC | __GFP_NOWARN);
+ if (unlikely(!nskb))
+ goto err;
+
+ skb_reserve(nskb, 16 + NET_IP_ALIGN);
+ headlen = nskb->end - nskb->data;
+ if (headlen > skb_headlen(skb))
+ headlen = skb_headlen(skb);
+ ret = skb_copy_bits(skb, 0, __skb_put(nskb, headlen), headlen);
+ BUG_ON(ret);
+
+ ninfo = skb_shinfo(nskb);
+ ninfo->gso_size = skb_shinfo(skb)->gso_size;
+ ninfo->gso_type = skb_shinfo(skb)->gso_type;
+
+ offset = headlen;
+ len = skb->len - headlen;
+
+ nskb->len = skb->len;
+ nskb->data_len = len;
+ nskb->truesize += len;
+
+ while (len) {
+ struct page *page;
+ int copy;
+ int zero;
+
+ if (unlikely(ninfo->nr_frags >= MAX_SKB_FRAGS)) {
+ dump_stack();
+ goto err_free;
+ }
+
+ copy = len >= PAGE_SIZE ? PAGE_SIZE : len;
+ zero = len >= PAGE_SIZE ? 0 : __GFP_ZERO;
+
+ page = alloc_page(GFP_ATOMIC | __GFP_NOWARN | zero);
+ if (unlikely(!page))
+ goto err_free;
+
+ ret = skb_copy_bits(skb, offset, page_address(page), copy);
+ BUG_ON(ret);
+
+ ninfo->frags[ninfo->nr_frags].page = page;
+ ninfo->frags[ninfo->nr_frags].page_offset = 0;
+ ninfo->frags[ninfo->nr_frags].size = copy;
+ ninfo->nr_frags++;
+
+ offset += copy;
+ len -= copy;
+ }
+
+ offset = nskb->data - skb->data;
+
+ nskb->h.raw = skb->h.raw + offset;
+ nskb->nh.raw = skb->nh.raw + offset;
+ nskb->mac.raw = skb->mac.raw + offset;
+
+ return nskb;
+
+ err_free:
+ kfree_skb(nskb);
+ err:
+ return NULL;
+}
+
+static inline int netbk_max_required_rx_slots(netif_t *netif)
+{
+ if (netif->features & (NETIF_F_SG|NETIF_F_TSO))
+ return MAX_SKB_FRAGS + 2; /* header + extra_info + frags */
+ return 1; /* all in one */
+}
+
+static inline int netbk_queue_full(netif_t *netif)
+{
+ RING_IDX peek = netif->rx_req_cons_peek;
+ RING_IDX needed = netbk_max_required_rx_slots(netif);
+
+ return ((netif->rx.sring->req_prod - peek) < needed) ||
+ ((netif->rx.rsp_prod_pvt + NET_RX_RING_SIZE - peek) < needed);
+}
+
+static void tx_queue_callback(unsigned long data)
+{
+ netif_t *netif = (netif_t *)data;
+ if (netif_schedulable(netif))
+ netif_wake_queue(netif->dev);
+}
+
+int netif_be_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ netif_t *netif = netdev_priv(dev);
+
+ BUG_ON(skb->dev != dev);
+
+ /* Drop the packet if the target domain has no receive buffers. */
+ if (unlikely(!netif_schedulable(netif) || netbk_queue_full(netif)))
+ goto drop;
+
+ /*
+ * Copy the packet here if it's destined for a flipping interface
+ * but isn't flippable (e.g. extra references to data).
+ * XXX For now we also copy skbuffs whose head crosses a page
+ * boundary, because netbk_gop_skb can't handle them.
+ */
+ if (!netif->copying_receiver ||
+ ((skb_headlen(skb) + offset_in_page(skb->data)) >= PAGE_SIZE)) {
+ struct sk_buff *nskb = netbk_copy_skb(skb);
+ if ( unlikely(nskb == NULL) )
+ goto drop;
+ /* Copy only the header fields we use in this driver. */
+ nskb->dev = skb->dev;
+ nskb->ip_summed = skb->ip_summed;
+ nskb->proto_data_valid = skb->proto_data_valid;
+ dev_kfree_skb(skb);
+ skb = nskb;
+ }
+
+ netif->rx_req_cons_peek += skb_shinfo(skb)->nr_frags + 1 +
+ !!skb_shinfo(skb)->gso_size;
+ netif_get(netif);
+
+ if (netbk_can_queue(dev) && netbk_queue_full(netif)) {
+ netif->rx.sring->req_event = netif->rx_req_cons_peek +
+ netbk_max_required_rx_slots(netif);
+ mb(); /* request notification /then/ check & stop the queue */
+ if (netbk_queue_full(netif)) {
+ netif_stop_queue(dev);
+ /*
+ * Schedule 500ms timeout to restart the queue, thus
+ * ensuring that an inactive queue will be drained.
+ * Packets will be immediately be dropped until more
+ * receive buffers become available (see
+ * netbk_queue_full() check above).
+ */
+ netif->tx_queue_timeout.data = (unsigned long)netif;
+ netif->tx_queue_timeout.function = tx_queue_callback;
+ __mod_timer(&netif->tx_queue_timeout, jiffies + HZ/2);
+ }
+ }
+
+ skb_queue_tail(&rx_queue, skb);
+ tasklet_schedule(&net_rx_tasklet);
+
+ return 0;
+
+ drop:
+ netif->stats.tx_dropped++;
+ dev_kfree_skb(skb);
+ return 0;
+}
+
+#if 0
+static void xen_network_done_notify(void)
+{
+ static struct net_device *eth0_dev = NULL;
+ if (unlikely(eth0_dev == NULL))
+ eth0_dev = __dev_get_by_name("eth0");
+ netif_rx_schedule(eth0_dev);
+}
+/*
+ * Add following to poll() function in NAPI driver (Tigon3 is example):
+ * if ( xen_network_done() )
+ * tg3_enable_ints(tp);
+ */
+int xen_network_done(void)
+{
+ return skb_queue_empty(&rx_queue);
+}
+#endif
+
+struct netrx_pending_operations {
+ unsigned trans_prod, trans_cons;
+ unsigned mmu_prod, mmu_mcl;
+ unsigned mcl_prod, mcl_cons;
+ unsigned copy_prod, copy_cons;
+ unsigned meta_prod, meta_cons;
+ mmu_update_t *mmu;
+ gnttab_transfer_t *trans;
+ gnttab_copy_t *copy;
+ multicall_entry_t *mcl;
+ struct netbk_rx_meta *meta;
+};
+
+/* Set up the grant operations for this fragment. If it's a flipping
+ interface, we also set up the unmap request from here. */
+static u16 netbk_gop_frag(netif_t *netif, struct netbk_rx_meta *meta,
+ int i, struct netrx_pending_operations *npo,
+ struct page *page, unsigned long size,
+ unsigned long offset)
+{
+ mmu_update_t *mmu;
+ gnttab_transfer_t *gop;
+ gnttab_copy_t *copy_gop;
+ multicall_entry_t *mcl;
+ netif_rx_request_t *req;
+ unsigned long old_mfn, new_mfn;
+ int idx = netif_page_index(page);
+
+ old_mfn = virt_to_mfn(page_address(page));
+
+ req = RING_GET_REQUEST(&netif->rx, netif->rx.req_cons + i);
+ if (netif->copying_receiver) {
+ /* The fragment needs to be copied rather than
+ flipped. */
+ meta->copy = 1;
+ copy_gop = npo->copy + npo->copy_prod++;
+ copy_gop->flags = GNTCOPY_dest_gref;
+ if (idx > -1) {
+ struct pending_tx_info *src_pend = &pending_tx_info[idx];
+ copy_gop->source.domid = src_pend->netif->domid;
+ copy_gop->source.u.ref = src_pend->req.gref;
+ copy_gop->flags |= GNTCOPY_source_gref;
+ } else {
+ copy_gop->source.domid = DOMID_SELF;
+ copy_gop->source.u.gmfn = old_mfn;
+ }
+ copy_gop->source.offset = offset;
+ copy_gop->dest.domid = netif->domid;
+ copy_gop->dest.offset = 0;
+ copy_gop->dest.u.ref = req->gref;
+ copy_gop->len = size;
+ } else {
+ meta->copy = 0;
+ if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+ new_mfn = alloc_mfn();
+
+ /*
+ * Set the new P2M table entry before
+ * reassigning the old data page. Heed the
+ * comment in pgtable-2level.h:pte_page(). :-)
+ */
+ set_phys_to_machine(page_to_pfn(page), new_mfn);
+
+ mcl = npo->mcl + npo->mcl_prod++;
+ MULTI_update_va_mapping(mcl,
+ (unsigned long)page_address(page),
+ pfn_pte_ma(new_mfn, PAGE_KERNEL),
+ 0);
+
+ mmu = npo->mmu + npo->mmu_prod++;
+ mmu->ptr = ((maddr_t)new_mfn << PAGE_SHIFT) |
+ MMU_MACHPHYS_UPDATE;
+ mmu->val = page_to_pfn(page);
+ }
+
+ gop = npo->trans + npo->trans_prod++;
+ gop->mfn = old_mfn;
+ gop->domid = netif->domid;
+ gop->ref = req->gref;
+ }
+ return req->id;
+}
+
+static void netbk_gop_skb(struct sk_buff *skb,
+ struct netrx_pending_operations *npo)
+{
+ netif_t *netif = netdev_priv(skb->dev);
+ int nr_frags = skb_shinfo(skb)->nr_frags;
+ int i;
+ int extra;
+ struct netbk_rx_meta *head_meta, *meta;
+
+ head_meta = npo->meta + npo->meta_prod++;
+ head_meta->frag.page_offset = skb_shinfo(skb)->gso_type;
+ head_meta->frag.size = skb_shinfo(skb)->gso_size;
+ extra = !!head_meta->frag.size + 1;
+
+ for (i = 0; i < nr_frags; i++) {
+ meta = npo->meta + npo->meta_prod++;
+ meta->frag = skb_shinfo(skb)->frags[i];
+ meta->id = netbk_gop_frag(netif, meta, i + extra, npo,
+ meta->frag.page,
+ meta->frag.size,
+ meta->frag.page_offset);
+ }
+
+ /*
+ * This must occur at the end to ensure that we don't trash skb_shinfo
+ * until we're done. We know that the head doesn't cross a page
+ * boundary because such packets get copied in netif_be_start_xmit.
+ */
+ head_meta->id = netbk_gop_frag(netif, head_meta, 0, npo,
+ virt_to_page(skb->data),
+ skb_headlen(skb),
+ offset_in_page(skb->data));
+
+ netif->rx.req_cons += nr_frags + extra;
+}
+
+static inline void netbk_free_pages(int nr_frags, struct netbk_rx_meta *meta)
+{
+ int i;
+
+ for (i = 0; i < nr_frags; i++)
+ put_page(meta[i].frag.page);
+}
+
+/* This is a twin to netbk_gop_skb. Assume that netbk_gop_skb was
+ used to set up the operations on the top of
+ netrx_pending_operations, which have since been done. Check that
+ they didn't give any errors and advance over them. */
+static int netbk_check_gop(int nr_frags, domid_t domid,
+ struct netrx_pending_operations *npo)
+{
+ multicall_entry_t *mcl;
+ gnttab_transfer_t *gop;
+ gnttab_copy_t *copy_op;
+ int status = NETIF_RSP_OKAY;
+ int i;
+
+ for (i = 0; i <= nr_frags; i++) {
+ if (npo->meta[npo->meta_cons + i].copy) {
+ copy_op = npo->copy + npo->copy_cons++;
+ if (copy_op->status != GNTST_okay) {
+ DPRINTK("Bad status %d from copy to DOM%d.\n",
+ copy_op->status, domid);
+ status = NETIF_RSP_ERROR;
+ }
+ } else {
+ if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+ mcl = npo->mcl + npo->mcl_cons++;
+ /* The update_va_mapping() must not fail. */
+ BUG_ON(mcl->result != 0);
+ }
+
+ gop = npo->trans + npo->trans_cons++;
+ /* Check the reassignment error code. */
+ if (gop->status != 0) {
+ DPRINTK("Bad status %d from grant transfer to DOM%u\n",
+ gop->status, domid);
+ /*
+ * Page no longer belongs to us unless
+ * GNTST_bad_page, but that should be
+ * a fatal error anyway.
+ */
+ BUG_ON(gop->status == GNTST_bad_page);
+ status = NETIF_RSP_ERROR;
+ }
+ }
+ }
+
+ return status;
+}
+
+static void netbk_add_frag_responses(netif_t *netif, int status,
+ struct netbk_rx_meta *meta, int nr_frags)
+{
+ int i;
+ unsigned long offset;
+
+ for (i = 0; i < nr_frags; i++) {
+ int id = meta[i].id;
+ int flags = (i == nr_frags - 1) ? 0 : NETRXF_more_data;
+
+ if (meta[i].copy)
+ offset = 0;
+ else
+ offset = meta[i].frag.page_offset;
+ make_rx_response(netif, id, status, offset,
+ meta[i].frag.size, flags);
+ }
+}
+
+static void net_rx_action(unsigned long unused)
+{
+ netif_t *netif = NULL;
+ s8 status;
+ u16 id, irq, flags;
+ netif_rx_response_t *resp;
+ multicall_entry_t *mcl;
+ struct sk_buff_head rxq;
+ struct sk_buff *skb;
+ int notify_nr = 0;
+ int ret;
+ int nr_frags;
+ int count;
+ unsigned long offset;
+
+ /*
+ * Putting hundreds of bytes on the stack is considered rude.
+ * Static works because a tasklet can only be on one CPU at any time.
+ */
+ static multicall_entry_t rx_mcl[NET_RX_RING_SIZE+3];
+ static mmu_update_t rx_mmu[NET_RX_RING_SIZE];
+ static gnttab_transfer_t grant_trans_op[NET_RX_RING_SIZE];
+ static gnttab_copy_t grant_copy_op[NET_RX_RING_SIZE];
+ static unsigned char rx_notify[NR_IRQS];
+ static u16 notify_list[NET_RX_RING_SIZE];
+ static struct netbk_rx_meta meta[NET_RX_RING_SIZE];
+
+ struct netrx_pending_operations npo = {
+ mmu: rx_mmu,
+ trans: grant_trans_op,
+ copy: grant_copy_op,
+ mcl: rx_mcl,
+ meta: meta};
+
+ skb_queue_head_init(&rxq);
+
+ count = 0;
+
+ while ((skb = skb_dequeue(&rx_queue)) != NULL) {
+ nr_frags = skb_shinfo(skb)->nr_frags;
+ *(int *)skb->cb = nr_frags;
+
+ if (!xen_feature(XENFEAT_auto_translated_physmap) &&
+ !((netif_t *)netdev_priv(skb->dev))->copying_receiver &&
+ check_mfn(nr_frags + 1)) {
+ /* Memory squeeze? Back off for an arbitrary while. */
+ if ( net_ratelimit() )
+ WPRINTK("Memory squeeze in netback "
+ "driver.\n");
+ mod_timer(&net_timer, jiffies + HZ);
+ skb_queue_head(&rx_queue, skb);
+ break;
+ }
+
+ netbk_gop_skb(skb, &npo);
+
+ count += nr_frags + 1;
+
+ __skb_queue_tail(&rxq, skb);
+
+ /* Filled the batch queue? */
+ if (count + MAX_SKB_FRAGS >= NET_RX_RING_SIZE)
+ break;
+ }
+
+ BUG_ON(npo.meta_prod > ARRAY_SIZE(meta));
+
+ npo.mmu_mcl = npo.mcl_prod;
+ if (npo.mcl_prod) {
+ BUG_ON(xen_feature(XENFEAT_auto_translated_physmap));
+ BUG_ON(npo.mmu_prod > ARRAY_SIZE(rx_mmu));
+ mcl = npo.mcl + npo.mcl_prod++;
+
+ BUG_ON(mcl[-1].op != __HYPERVISOR_update_va_mapping);
+ mcl[-1].args[MULTI_UVMFLAGS_INDEX] = UVMF_TLB_FLUSH|UVMF_ALL;
+
+ mcl->op = __HYPERVISOR_mmu_update;
+ mcl->args[0] = (unsigned long)rx_mmu;
+ mcl->args[1] = npo.mmu_prod;
+ mcl->args[2] = 0;
+ mcl->args[3] = DOMID_SELF;
+ }
+
+ if (npo.trans_prod) {
+ BUG_ON(npo.trans_prod > ARRAY_SIZE(grant_trans_op));
+ mcl = npo.mcl + npo.mcl_prod++;
+ mcl->op = __HYPERVISOR_grant_table_op;
+ mcl->args[0] = GNTTABOP_transfer;
+ mcl->args[1] = (unsigned long)grant_trans_op;
+ mcl->args[2] = npo.trans_prod;
+ }
+
+ if (npo.copy_prod) {
+ BUG_ON(npo.copy_prod > ARRAY_SIZE(grant_copy_op));
+ mcl = npo.mcl + npo.mcl_prod++;
+ mcl->op = __HYPERVISOR_grant_table_op;
+ mcl->args[0] = GNTTABOP_copy;
+ mcl->args[1] = (unsigned long)grant_copy_op;
+ mcl->args[2] = npo.copy_prod;
+ }
+
+ /* Nothing to do? */
+ if (!npo.mcl_prod)
+ return;
+
+ BUG_ON(npo.mcl_prod > ARRAY_SIZE(rx_mcl));
+
+ ret = HYPERVISOR_multicall(npo.mcl, npo.mcl_prod);
+ BUG_ON(ret != 0);
+ /* The mmu_machphys_update() must not fail. */
+ BUG_ON(npo.mmu_mcl && npo.mcl[npo.mmu_mcl].result != 0);
+
+ while ((skb = __skb_dequeue(&rxq)) != NULL) {
+ nr_frags = *(int *)skb->cb;
+
+ netif = netdev_priv(skb->dev);
+ /* We can't rely on skb_release_data to release the
+ pages used by fragments for us, since it tries to
+ touch the pages in the fraglist. If we're in
+ flipping mode, that doesn't work. In copying mode,
+ we still have access to all of the pages, and so
+ it's safe to let release_data deal with it. */
+ /* (Freeing the fragments is safe since we copy
+ non-linear skbs destined for flipping interfaces) */
+ if (!netif->copying_receiver) {
+ atomic_set(&(skb_shinfo(skb)->dataref), 1);
+ skb_shinfo(skb)->frag_list = NULL;
+ skb_shinfo(skb)->nr_frags = 0;
+ netbk_free_pages(nr_frags, meta + npo.meta_cons + 1);
+ }
+
+ netif->stats.tx_bytes += skb->len;
+ netif->stats.tx_packets++;
+
+ status = netbk_check_gop(nr_frags, netif->domid, &npo);
+
+ id = meta[npo.meta_cons].id;
+ flags = nr_frags ? NETRXF_more_data : 0;
+
+ if (skb->ip_summed == CHECKSUM_HW) /* local packet? */
+ flags |= NETRXF_csum_blank | NETRXF_data_validated;
+ else if (skb->proto_data_valid) /* remote but checksummed? */
+ flags |= NETRXF_data_validated;
+
+ if (meta[npo.meta_cons].copy)
+ offset = 0;
+ else
+ offset = offset_in_page(skb->data);
+ resp = make_rx_response(netif, id, status, offset,
+ skb_headlen(skb), flags);
+
+ if (meta[npo.meta_cons].frag.size) {
+ struct netif_extra_info *gso =
+ (struct netif_extra_info *)
+ RING_GET_RESPONSE(&netif->rx,
+ netif->rx.rsp_prod_pvt++);
+
+ resp->flags |= NETRXF_extra_info;
+
+ gso->u.gso.size = meta[npo.meta_cons].frag.size;
+ gso->u.gso.type = XEN_NETIF_GSO_TYPE_TCPV4;
+ gso->u.gso.pad = 0;
+ gso->u.gso.features = 0;
+
+ gso->type = XEN_NETIF_EXTRA_TYPE_GSO;
+ gso->flags = 0;
+ }
+
+ netbk_add_frag_responses(netif, status,
+ meta + npo.meta_cons + 1,
+ nr_frags);
+
+ RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netif->rx, ret);
+ irq = netif->irq;
+ if (ret && !rx_notify[irq]) {
+ rx_notify[irq] = 1;
+ notify_list[notify_nr++] = irq;
+ }
+
+ if (netif_queue_stopped(netif->dev) &&
+ netif_schedulable(netif) &&
+ !netbk_queue_full(netif))
+ netif_wake_queue(netif->dev);
+
+ netif_put(netif);
+ dev_kfree_skb(skb);
+ npo.meta_cons += nr_frags + 1;
+ }
+
+ while (notify_nr != 0) {
+ irq = notify_list[--notify_nr];
+ rx_notify[irq] = 0;
+ notify_remote_via_irq(irq);
+ }
+
+ /* More work to do? */
+ if (!skb_queue_empty(&rx_queue) && !timer_pending(&net_timer))
+ tasklet_schedule(&net_rx_tasklet);
+#if 0
+ else
+ xen_network_done_notify();
+#endif
+}
+
+static void net_alarm(unsigned long unused)
+{
+ tasklet_schedule(&net_rx_tasklet);
+}
+
+static void netbk_tx_pending_timeout(unsigned long unused)
+{
+ tasklet_schedule(&net_tx_tasklet);
+}
+
+struct net_device_stats *netif_be_get_stats(struct net_device *dev)
+{
+ netif_t *netif = netdev_priv(dev);
+ return &netif->stats;
+}
+
+static int __on_net_schedule_list(netif_t *netif)
+{
+ return netif->list.next != NULL;
+}
+
+static void remove_from_net_schedule_list(netif_t *netif)
+{
+ spin_lock_irq(&net_schedule_list_lock);
+ if (likely(__on_net_schedule_list(netif))) {
+ list_del(&netif->list);
+ netif->list.next = NULL;
+ netif_put(netif);
+ }
+ spin_unlock_irq(&net_schedule_list_lock);
+}
+
+static void add_to_net_schedule_list_tail(netif_t *netif)
+{
+ if (__on_net_schedule_list(netif))
+ return;
+
+ spin_lock_irq(&net_schedule_list_lock);
+ if (!__on_net_schedule_list(netif) &&
+ likely(netif_schedulable(netif))) {
+ list_add_tail(&netif->list, &net_schedule_list);
+ netif_get(netif);
+ }
+ spin_unlock_irq(&net_schedule_list_lock);
+}
+
+/*
+ * Note on CONFIG_XEN_NETDEV_PIPELINED_TRANSMITTER:
+ * If this driver is pipelining transmit requests then we can be very
+ * aggressive in avoiding new-packet notifications -- frontend only needs to
+ * send a notification if there are no outstanding unreceived responses.
+ * If we may be buffer transmit buffers for any reason then we must be rather
+ * more conservative and treat this as the final check for pending work.
+ */
+void netif_schedule_work(netif_t *netif)
+{
+ int more_to_do;
+
+#ifdef CONFIG_XEN_NETDEV_PIPELINED_TRANSMITTER
+ more_to_do = RING_HAS_UNCONSUMED_REQUESTS(&netif->tx);
+#else
+ RING_FINAL_CHECK_FOR_REQUESTS(&netif->tx, more_to_do);
+#endif
+
+ if (more_to_do) {
+ add_to_net_schedule_list_tail(netif);
+ maybe_schedule_tx_action();
+ }
+}
+
+void netif_deschedule_work(netif_t *netif)
+{
+ remove_from_net_schedule_list(netif);
+}
+
+
+static void tx_add_credit(netif_t *netif)
+{
+ unsigned long max_burst, max_credit;
+
+ /*
+ * Allow a burst big enough to transmit a jumbo packet of up to 128kB.
+ * Otherwise the interface can seize up due to insufficient credit.
+ */
+ max_burst = RING_GET_REQUEST(&netif->tx, netif->tx.req_cons)->size;
+ max_burst = min(max_burst, 131072UL);
+ max_burst = max(max_burst, netif->credit_bytes);
+
+ /* Take care that adding a new chunk of credit doesn't wrap to zero. */
+ max_credit = netif->remaining_credit + netif->credit_bytes;
+ if (max_credit < netif->remaining_credit)
+ max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */
+
+ netif->remaining_credit = min(max_credit, max_burst);
+}
+
+static void tx_credit_callback(unsigned long data)
+{
+ netif_t *netif = (netif_t *)data;
+ tx_add_credit(netif);
+ netif_schedule_work(netif);
+}
+
+static inline int copy_pending_req(PEND_RING_IDX pending_idx)
+{
+ return gnttab_copy_grant_page(grant_tx_handle[pending_idx],
+ &mmap_pages[pending_idx]);
+}
+
+inline static void net_tx_action_dealloc(void)
+{
+ struct netbk_tx_pending_inuse *inuse, *n;
+ gnttab_unmap_grant_ref_t *gop;
+ u16 pending_idx;
+ PEND_RING_IDX dc, dp;
+ netif_t *netif;
+ int ret;
+ LIST_HEAD(list);
+
+ dc = dealloc_cons;
+ gop = tx_unmap_ops;
+
+ /*
+ * Free up any grants we have finished using
+ */
+ do {
+ dp = dealloc_prod;
+
+ /* Ensure we see all indices enqueued by netif_idx_release(). */
+ smp_rmb();
+
+ while (dc != dp) {
+ unsigned long pfn;
+
+ pending_idx = dealloc_ring[MASK_PEND_IDX(dc++)];
+ list_move_tail(&pending_inuse[pending_idx].list, &list);
+
+ pfn = idx_to_pfn(pending_idx);
+ /* Already unmapped? */
+ if (!phys_to_machine_mapping_valid(pfn))
+ continue;
+
+ gnttab_set_unmap_op(gop, idx_to_kaddr(pending_idx),
+ GNTMAP_host_map,
+ grant_tx_handle[pending_idx]);
+ gop++;
+ }
+
+ if (netbk_copy_skb_mode != NETBK_DELAYED_COPY_SKB ||
+ list_empty(&pending_inuse_head))
+ break;
+
+ /* Copy any entries that have been pending for too long. */
+ list_for_each_entry_safe(inuse, n, &pending_inuse_head, list) {
+ if (time_after(inuse->alloc_time + HZ / 2, jiffies))
+ break;
+
+ switch (copy_pending_req(inuse - pending_inuse)) {
+ case 0:
+ list_move_tail(&inuse->list, &list);
+ continue;
+ case -EBUSY:
+ list_del_init(&inuse->list);
+ continue;
+ case -ENOENT:
+ continue;
+ }
+
+ break;
+ }
+ } while (dp != dealloc_prod);
+
+ dealloc_cons = dc;
+
+ ret = HYPERVISOR_grant_table_op(
+ GNTTABOP_unmap_grant_ref, tx_unmap_ops, gop - tx_unmap_ops);
+ BUG_ON(ret);
+
+ list_for_each_entry_safe(inuse, n, &list, list) {
+ pending_idx = inuse - pending_inuse;
+
+ netif = pending_tx_info[pending_idx].netif;
+
+ make_tx_response(netif, &pending_tx_info[pending_idx].req,
+ NETIF_RSP_OKAY);
+
+ /* Ready for next use. */
+ gnttab_reset_grant_page(mmap_pages[pending_idx]);
+
+ pending_ring[MASK_PEND_IDX(pending_prod++)] = pending_idx;
+
+ netif_put(netif);
+
+ list_del_init(&inuse->list);
+ }
+}
+
+static void netbk_tx_err(netif_t *netif, netif_tx_request_t *txp, RING_IDX end)
+{
+ RING_IDX cons = netif->tx.req_cons;
+
+ do {
+ make_tx_response(netif, txp, NETIF_RSP_ERROR);
+ if (cons >= end)
+ break;
+ txp = RING_GET_REQUEST(&netif->tx, cons++);
+ } while (1);
+ netif->tx.req_cons = cons;
+ netif_schedule_work(netif);
+ netif_put(netif);
+}
+
+static int netbk_count_requests(netif_t *netif, netif_tx_request_t *first,
+ netif_tx_request_t *txp, int work_to_do)
+{
+ RING_IDX cons = netif->tx.req_cons;
+ int frags = 0;
+
+ if (!(first->flags & NETTXF_more_data))
+ return 0;
+
+ do {
+ if (frags >= work_to_do) {
+ DPRINTK("Need more frags\n");
+ return -frags;
+ }
+
+ if (unlikely(frags >= MAX_SKB_FRAGS)) {
+ DPRINTK("Too many frags\n");
+ return -frags;
+ }
+
+ memcpy(txp, RING_GET_REQUEST(&netif->tx, cons + frags),
+ sizeof(*txp));
+ if (txp->size > first->size) {
+ DPRINTK("Frags galore\n");
+ return -frags;
+ }
+
+ first->size -= txp->size;
+ frags++;
+
+ if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) {
+ DPRINTK("txp->offset: %x, size: %u\n",
+ txp->offset, txp->size);
+ return -frags;
+ }
+ } while ((txp++)->flags & NETTXF_more_data);
+
+ return frags;
+}
+
+static gnttab_map_grant_ref_t *netbk_get_requests(netif_t *netif,
+ struct sk_buff *skb,
+ netif_tx_request_t *txp,
+ gnttab_map_grant_ref_t *mop)
+{
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
+ skb_frag_t *frags = shinfo->frags;
+ unsigned long pending_idx = *((u16 *)skb->data);
+ int i, start;
+
+ /* Skip first skb fragment if it is on same page as header fragment. */
+ start = ((unsigned long)shinfo->frags[0].page == pending_idx);
+
+ for (i = start; i < shinfo->nr_frags; i++, txp++) {
+ pending_idx = pending_ring[MASK_PEND_IDX(pending_cons++)];
+
+ gnttab_set_map_op(mop++, idx_to_kaddr(pending_idx),
+ GNTMAP_host_map | GNTMAP_readonly,
+ txp->gref, netif->domid);
+
+ memcpy(&pending_tx_info[pending_idx].req, txp, sizeof(*txp));
+ netif_get(netif);
+ pending_tx_info[pending_idx].netif = netif;
+ frags[i].page = (void *)pending_idx;
+ }
+
+ return mop;
+}
+
+static int netbk_tx_check_mop(struct sk_buff *skb,
+ gnttab_map_grant_ref_t **mopp)
+{
+ gnttab_map_grant_ref_t *mop = *mopp;
+ int pending_idx = *((u16 *)skb->data);
+ netif_t *netif = pending_tx_info[pending_idx].netif;
+ netif_tx_request_t *txp;
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
+ int nr_frags = shinfo->nr_frags;
+ int i, err, start;
+
+ /* Check status of header. */
+ err = mop->status;
+ if (unlikely(err)) {
+ txp = &pending_tx_info[pending_idx].req;
+ make_tx_response(netif, txp, NETIF_RSP_ERROR);
+ pending_ring[MASK_PEND_IDX(pending_prod++)] = pending_idx;
+ netif_put(netif);
+ } else {
+ set_phys_to_machine(
+ __pa(idx_to_kaddr(pending_idx)) >> PAGE_SHIFT,
+ FOREIGN_FRAME(mop->dev_bus_addr >> PAGE_SHIFT));
+ grant_tx_handle[pending_idx] = mop->handle;
+ }
+
+ /* Skip first skb fragment if it is on same page as header fragment. */
+ start = ((unsigned long)shinfo->frags[0].page == pending_idx);
+
+ for (i = start; i < nr_frags; i++) {
+ int j, newerr;
+
+ pending_idx = (unsigned long)shinfo->frags[i].page;
+
+ /* Check error status: if okay then remember grant handle. */
+ newerr = (++mop)->status;
+ if (likely(!newerr)) {
+ set_phys_to_machine(
+ __pa(idx_to_kaddr(pending_idx))>>PAGE_SHIFT,
+ FOREIGN_FRAME(mop->dev_bus_addr>>PAGE_SHIFT));
+ grant_tx_handle[pending_idx] = mop->handle;
+ /* Had a previous error? Invalidate this fragment. */
+ if (unlikely(err))
+ netif_idx_release(pending_idx);
+ continue;
+ }
+
+ /* Error on this fragment: respond to client with an error. */
+ txp = &pending_tx_info[pending_idx].req;
+ make_tx_response(netif, txp, NETIF_RSP_ERROR);
+ pending_ring[MASK_PEND_IDX(pending_prod++)] = pending_idx;
+ netif_put(netif);
+
+ /* Not the first error? Preceding frags already invalidated. */
+ if (err)
+ continue;
+
+ /* First error: invalidate header and preceding fragments. */
+ pending_idx = *((u16 *)skb->data);
+ netif_idx_release(pending_idx);
+ for (j = start; j < i; j++) {
+ pending_idx = (unsigned long)shinfo->frags[i].page;
+ netif_idx_release(pending_idx);
+ }
+
+ /* Remember the error: invalidate all subsequent fragments. */
+ err = newerr;
+ }
+
+ *mopp = mop + 1;
+ return err;
+}
+
+static void netbk_fill_frags(struct sk_buff *skb)
+{
+ struct skb_shared_info *shinfo = skb_shinfo(skb);
+ int nr_frags = shinfo->nr_frags;
+ int i;
+
+ for (i = 0; i < nr_frags; i++) {
+ skb_frag_t *frag = shinfo->frags + i;
+ netif_tx_request_t *txp;
+ unsigned long pending_idx;
+
+ pending_idx = (unsigned long)frag->page;
+
+ pending_inuse[pending_idx].alloc_time = jiffies;
+ list_add_tail(&pending_inuse[pending_idx].list,
+ &pending_inuse_head);
+
+ txp = &pending_tx_info[pending_idx].req;
+ frag->page = virt_to_page(idx_to_kaddr(pending_idx));
+ frag->size = txp->size;
+ frag->page_offset = txp->offset;
+
+ skb->len += txp->size;
+ skb->data_len += txp->size;
+ skb->truesize += txp->size;
+ }
+}
+
+int netbk_get_extras(netif_t *netif, struct netif_extra_info *extras,
+ int work_to_do)
+{
+ struct netif_extra_info extra;
+ RING_IDX cons = netif->tx.req_cons;
+
+ do {
+ if (unlikely(work_to_do-- <= 0)) {
+ DPRINTK("Missing extra info\n");
+ return -EBADR;
+ }
+
+ memcpy(&extra, RING_GET_REQUEST(&netif->tx, cons),
+ sizeof(extra));
+ if (unlikely(!extra.type ||
+ extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
+ netif->tx.req_cons = ++cons;
+ DPRINTK("Invalid extra type: %d\n", extra.type);
+ return -EINVAL;
+ }
+
+ memcpy(&extras[extra.type - 1], &extra, sizeof(extra));
+ netif->tx.req_cons = ++cons;
+ } while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE);
+
+ return work_to_do;
+}
+
+static int netbk_set_skb_gso(struct sk_buff *skb, struct netif_extra_info *gso)
+{
+ if (!gso->u.gso.size) {
+ DPRINTK("GSO size must not be zero.\n");
+ return -EINVAL;
+ }
+
+ /* Currently only TCPv4 S.O. is supported. */
+ if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4) {
+ DPRINTK("Bad GSO type %d.\n", gso->u.gso.type);
+ return -EINVAL;
+ }
+
+ skb_shinfo(skb)->gso_size = gso->u.gso.size;
+ skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
+
+ /* Header must be checked, and gso_segs computed. */
+ skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
+ skb_shinfo(skb)->gso_segs = 0;
+
+ return 0;
+}
+
+/* Called after netfront has transmitted */
+static void net_tx_action(unsigned long unused)
+{
+ struct list_head *ent;
+ struct sk_buff *skb;
+ netif_t *netif;
+ netif_tx_request_t txreq;
+ netif_tx_request_t txfrags[MAX_SKB_FRAGS];
+ struct netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
+ u16 pending_idx;
+ RING_IDX i;
+ gnttab_map_grant_ref_t *mop;
+ unsigned int data_len;
+ int ret, work_to_do;
+
+ if (dealloc_cons != dealloc_prod)
+ net_tx_action_dealloc();
+
+ mop = tx_map_ops;
+ while (((NR_PENDING_REQS + MAX_SKB_FRAGS) < MAX_PENDING_REQS) &&
+ !list_empty(&net_schedule_list)) {
+ /* Get a netif from the list with work to do. */
+ ent = net_schedule_list.next;
+ netif = list_entry(ent, netif_t, list);
+ netif_get(netif);
+ remove_from_net_schedule_list(netif);
+
+ RING_FINAL_CHECK_FOR_REQUESTS(&netif->tx, work_to_do);
+ if (!work_to_do) {
+ netif_put(netif);
+ continue;
+ }
+
+ i = netif->tx.req_cons;
+ rmb(); /* Ensure that we see the request before we copy it. */
+ memcpy(&txreq, RING_GET_REQUEST(&netif->tx, i), sizeof(txreq));
+
+ /* Credit-based scheduling. */
+ if (txreq.size > netif->remaining_credit) {
+ unsigned long now = jiffies;
+ unsigned long next_credit =
+ netif->credit_timeout.expires +
+ msecs_to_jiffies(netif->credit_usec / 1000);
+
+ /* Timer could already be pending in rare cases. */
+ if (timer_pending(&netif->credit_timeout)) {
+ netif_put(netif);
+ continue;
+ }
+
+ /* Passed the point where we can replenish credit? */
+ if (time_after_eq(now, next_credit)) {
+ netif->credit_timeout.expires = now;
+ tx_add_credit(netif);
+ }
+
+ /* Still too big to send right now? Set a callback. */
+ if (txreq.size > netif->remaining_credit) {
+ netif->credit_timeout.data =
+ (unsigned long)netif;
+ netif->credit_timeout.function =
+ tx_credit_callback;
+ __mod_timer(&netif->credit_timeout,
+ next_credit);
+ netif_put(netif);
+ continue;
+ }
+ }
+ netif->remaining_credit -= txreq.size;
+
+ work_to_do--;
+ netif->tx.req_cons = ++i;
+
+ memset(extras, 0, sizeof(extras));
+ if (txreq.flags & NETTXF_extra_info) {
+ work_to_do = netbk_get_extras(netif, extras,
+ work_to_do);
+ i = netif->tx.req_cons;
+ if (unlikely(work_to_do < 0)) {
+ netbk_tx_err(netif, &txreq, i);
+ continue;
+ }
+ }
+
+ ret = netbk_count_requests(netif, &txreq, txfrags, work_to_do);
+ if (unlikely(ret < 0)) {
+ netbk_tx_err(netif, &txreq, i - ret);
+ continue;
+ }
+ i += ret;
+
+ if (unlikely(txreq.size < ETH_HLEN)) {
+ DPRINTK("Bad packet size: %d\n", txreq.size);
+ netbk_tx_err(netif, &txreq, i);
+ continue;
+ }
+
+ /* No crossing a page as the payload mustn't fragment. */
+ if (unlikely((txreq.offset + txreq.size) > PAGE_SIZE)) {
+ DPRINTK("txreq.offset: %x, size: %u, end: %lu\n",
+ txreq.offset, txreq.size,
+ (txreq.offset &~PAGE_MASK) + txreq.size);
+ netbk_tx_err(netif, &txreq, i);
+ continue;
+ }
+
+ pending_idx = pending_ring[MASK_PEND_IDX(pending_cons)];
+
+ data_len = (txreq.size > PKT_PROT_LEN &&
+ ret < MAX_SKB_FRAGS) ?
+ PKT_PROT_LEN : txreq.size;
+
+ skb = alloc_skb(data_len + 16 + NET_IP_ALIGN,
+ GFP_ATOMIC | __GFP_NOWARN);
+ if (unlikely(skb == NULL)) {
+ DPRINTK("Can't allocate a skb in start_xmit.\n");
+ netbk_tx_err(netif, &txreq, i);
+ break;
+ }
+
+ /* Packets passed to netif_rx() must have some headroom. */
+ skb_reserve(skb, 16 + NET_IP_ALIGN);
+
+ if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) {
+ struct netif_extra_info *gso;
+ gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1];
+
+ if (netbk_set_skb_gso(skb, gso)) {
+ kfree_skb(skb);
+ netbk_tx_err(netif, &txreq, i);
+ continue;
+ }
+ }
+
+ gnttab_set_map_op(mop, idx_to_kaddr(pending_idx),
+ GNTMAP_host_map | GNTMAP_readonly,
+ txreq.gref, netif->domid);
+ mop++;
+
+ memcpy(&pending_tx_info[pending_idx].req,
+ &txreq, sizeof(txreq));
+ pending_tx_info[pending_idx].netif = netif;
+ *((u16 *)skb->data) = pending_idx;
+
+ __skb_put(skb, data_len);
+
+ skb_shinfo(skb)->nr_frags = ret;
+ if (data_len < txreq.size) {
+ skb_shinfo(skb)->nr_frags++;
+ skb_shinfo(skb)->frags[0].page =
+ (void *)(unsigned long)pending_idx;
+ } else {
+ /* Discriminate from any valid pending_idx value. */
+ skb_shinfo(skb)->frags[0].page = (void *)~0UL;
+ }
+
+ if (skb->data_len < skb_shinfo(skb)->gso_size) {
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
+ }
+
+ __skb_queue_tail(&tx_queue, skb);
+
+ pending_cons++;
+
+ mop = netbk_get_requests(netif, skb, txfrags, mop);
+
+ netif->tx.req_cons = i;
+ netif_schedule_work(netif);
+
+ if ((mop - tx_map_ops) >= ARRAY_SIZE(tx_map_ops))
+ break;
+ }
+
+ if (mop == tx_map_ops)
+ return;
+
+ ret = HYPERVISOR_grant_table_op(
+ GNTTABOP_map_grant_ref, tx_map_ops, mop - tx_map_ops);
+ BUG_ON(ret);
+
+ mop = tx_map_ops;
+ while ((skb = __skb_dequeue(&tx_queue)) != NULL) {
+ netif_tx_request_t *txp;
+
+ pending_idx = *((u16 *)skb->data);
+ netif = pending_tx_info[pending_idx].netif;
+ txp = &pending_tx_info[pending_idx].req;
+
+ /* Check the remap error code. */
+ if (unlikely(netbk_tx_check_mop(skb, &mop))) {
+ DPRINTK("netback grant failed.\n");
+ skb_shinfo(skb)->nr_frags = 0;
+ kfree_skb(skb);
+ continue;
+ }
+
+ data_len = skb->len;
+ memcpy(skb->data,
+ (void *)(idx_to_kaddr(pending_idx)|txp->offset),
+ data_len);
+ if (data_len < txp->size) {
+ /* Append the packet payload as a fragment. */
+ txp->offset += data_len;
+ txp->size -= data_len;
+ } else {
+ /* Schedule a response immediately. */
+ netif_idx_release(pending_idx);
+ }
+
+ /*
+ * Old frontends do not assert data_validated but we
+ * can infer it from csum_blank so test both flags.
+ */
+ if (txp->flags & (NETTXF_data_validated|NETTXF_csum_blank)) {
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ skb->proto_data_valid = 1;
+ } else {
+ skb->ip_summed = CHECKSUM_NONE;
+ skb->proto_data_valid = 0;
+ }
+ skb->proto_csum_blank = !!(txp->flags & NETTXF_csum_blank);
+
+ netbk_fill_frags(skb);
+
+ skb->dev = netif->dev;
+ skb->protocol = eth_type_trans(skb, skb->dev);
+
+ netif->stats.rx_bytes += skb->len;
+ netif->stats.rx_packets++;
+
+ if (unlikely(netbk_copy_skb_mode == NETBK_ALWAYS_COPY_SKB) &&
+ unlikely(skb_linearize(skb))) {
+ DPRINTK("Can't linearize skb in net_tx_action.\n");
+ kfree_skb(skb);
+ continue;
+ }
+
+ netif_rx(skb);
+ netif->dev->last_rx = jiffies;
+ }
+
+ if (netbk_copy_skb_mode == NETBK_DELAYED_COPY_SKB &&
+ !list_empty(&pending_inuse_head)) {
+ struct netbk_tx_pending_inuse *oldest;
+
+ oldest = list_entry(pending_inuse_head.next,
+ struct netbk_tx_pending_inuse, list);
+ mod_timer(&netbk_tx_pending_timer, oldest->alloc_time + HZ);
+ }
+}
+
+static void netif_idx_release(u16 pending_idx)
+{
+ static DEFINE_SPINLOCK(_lock);
+ unsigned long flags;
+
+ spin_lock_irqsave(&_lock, flags);
+ dealloc_ring[MASK_PEND_IDX(dealloc_prod)] = pending_idx;
+ /* Sync with net_tx_action_dealloc: insert idx /then/ incr producer. */
+ smp_wmb();
+ dealloc_prod++;
+ spin_unlock_irqrestore(&_lock, flags);
+
+ tasklet_schedule(&net_tx_tasklet);
+}
+
+static void netif_page_release(struct page *page, unsigned int order)
+{
+ int idx = netif_page_index(page);
+ BUG_ON(order);
+ BUG_ON(idx < 0);
+ netif_idx_release(idx);
+}
+
+irqreturn_t netif_be_int(int irq, void *dev_id, struct pt_regs *regs)
+{
+ netif_t *netif = dev_id;
+
+ add_to_net_schedule_list_tail(netif);
+ maybe_schedule_tx_action();
+
+ if (netif_schedulable(netif) && !netbk_queue_full(netif))
+ netif_wake_queue(netif->dev);
+
+ return IRQ_HANDLED;
+}
+
+static void make_tx_response(netif_t *netif,
+ netif_tx_request_t *txp,
+ s8 st)
+{
+ RING_IDX i = netif->tx.rsp_prod_pvt;
+ netif_tx_response_t *resp;
+ int notify;
+
+ resp = RING_GET_RESPONSE(&netif->tx, i);
+ resp->id = txp->id;
+ resp->status = st;
+
+ if (txp->flags & NETTXF_extra_info)
+ RING_GET_RESPONSE(&netif->tx, ++i)->status = NETIF_RSP_NULL;
+
+ netif->tx.rsp_prod_pvt = ++i;
+ RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&netif->tx, notify);
+ if (notify)
+ notify_remote_via_irq(netif->irq);
+
+#ifdef CONFIG_XEN_NETDEV_PIPELINED_TRANSMITTER
+ if (i == netif->tx.req_cons) {
+ int more_to_do;
+ RING_FINAL_CHECK_FOR_REQUESTS(&netif->tx, more_to_do);
+ if (more_to_do)
+ add_to_net_schedule_list_tail(netif);
+ }
+#endif
+}
+
+static netif_rx_response_t *make_rx_response(netif_t *netif,
+ u16 id,
+ s8 st,
+ u16 offset,
+ u16 size,
+ u16 flags)
+{
+ RING_IDX i = netif->rx.rsp_prod_pvt;
+ netif_rx_response_t *resp;
+
+ resp = RING_GET_RESPONSE(&netif->rx, i);
+ resp->offset = offset;
+ resp->flags = flags;
+ resp->id = id;
+ resp->status = (s16)size;
+ if (st < 0)
+ resp->status = (s16)st;
+
+ netif->rx.rsp_prod_pvt = ++i;
+
+ return resp;
+}
+
+#ifdef NETBE_DEBUG_INTERRUPT
+static irqreturn_t netif_be_dbg(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct list_head *ent;
+ netif_t *netif;
+ int i = 0;
+
+ printk(KERN_ALERT "netif_schedule_list:\n");
+ spin_lock_irq(&net_schedule_list_lock);
+
+ list_for_each (ent, &net_schedule_list) {
+ netif = list_entry(ent, netif_t, list);
+ printk(KERN_ALERT " %d: private(rx_req_cons=%08x "
+ "rx_resp_prod=%08x\n",
+ i, netif->rx.req_cons, netif->rx.rsp_prod_pvt);
+ printk(KERN_ALERT " tx_req_cons=%08x tx_resp_prod=%08x)\n",
+ netif->tx.req_cons, netif->tx.rsp_prod_pvt);
+ printk(KERN_ALERT " shared(rx_req_prod=%08x "
+ "rx_resp_prod=%08x\n",
+ netif->rx.sring->req_prod, netif->rx.sring->rsp_prod);
+ printk(KERN_ALERT " rx_event=%08x tx_req_prod=%08x\n",
+ netif->rx.sring->rsp_event, netif->tx.sring->req_prod);
+ printk(KERN_ALERT " tx_resp_prod=%08x, tx_event=%08x)\n",
+ netif->tx.sring->rsp_prod, netif->tx.sring->rsp_event);
+ i++;
+ }
+
+ spin_unlock_irq(&net_schedule_list_lock);
+ printk(KERN_ALERT " ** End of netif_schedule_list **\n");
+
+ return IRQ_HANDLED;
+}
+#endif
+
+static int __init netback_init(void)
+{
+ int i;
+ struct page *page;
+
+ if (!is_running_on_xen())
+ return -ENODEV;
+
+ /* We can increase reservation by this much in net_rx_action(). */
+ balloon_update_driver_allowance(NET_RX_RING_SIZE);
+
+ skb_queue_head_init(&rx_queue);
+ skb_queue_head_init(&tx_queue);
+
+ init_timer(&net_timer);
+ net_timer.data = 0;
+ net_timer.function = net_alarm;
+
+ init_timer(&netbk_tx_pending_timer);
+ netbk_tx_pending_timer.data = 0;
+ netbk_tx_pending_timer.function = netbk_tx_pending_timeout;
+
+ mmap_pages = alloc_empty_pages_and_pagevec(MAX_PENDING_REQS);
+ if (mmap_pages == NULL) {
+ printk("%s: out of memory\n", __FUNCTION__);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < MAX_PENDING_REQS; i++) {
+ page = mmap_pages[i];
+ SetPageForeign(page, netif_page_release);
+ netif_set_page_index(page, i);
+ INIT_LIST_HEAD(&pending_inuse[i].list);
+ }
+
+ pending_cons = 0;
+ pending_prod = MAX_PENDING_REQS;
+ for (i = 0; i < MAX_PENDING_REQS; i++)
+ pending_ring[i] = i;
+
+ spin_lock_init(&net_schedule_list_lock);
+ INIT_LIST_HEAD(&net_schedule_list);
+
+ netbk_copy_skb_mode = NETBK_DONT_COPY_SKB;
+ if (MODPARM_copy_skb) {
+ if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_and_replace,
+ NULL, 0))
+ netbk_copy_skb_mode = NETBK_ALWAYS_COPY_SKB;
+ else
+ netbk_copy_skb_mode = NETBK_DELAYED_COPY_SKB;
+ }
+
+ netif_accel_init();
+
+ netif_xenbus_init();
+
+#ifdef NETBE_DEBUG_INTERRUPT
+ (void)bind_virq_to_irqhandler(VIRQ_DEBUG,
+ 0,
+ netif_be_dbg,
+ SA_SHIRQ,
+ "net-be-dbg",
+ &netif_be_dbg);
+#endif
+
+ return 0;
+}
+
+module_init(netback_init);
+
+MODULE_LICENSE("Dual BSD/GPL");
--- /dev/null
+/* Xenbus code for netif backend
+ Copyright (C) 2005 Rusty Russell <rusty@rustcorp.com.au>
+ Copyright (C) 2005 XenSource Ltd
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include <stdarg.h>
+#include <linux/module.h>
+#include <xen/xenbus.h>
+#include "common.h"
+
+#if 0
+#undef DPRINTK
+#define DPRINTK(fmt, args...) \
+ printk("netback/xenbus (%s:%d) " fmt ".\n", __FUNCTION__, __LINE__, ##args)
+#endif
+
+
+static int connect_rings(struct backend_info *);
+static void connect(struct backend_info *);
+static void backend_create_netif(struct backend_info *be);
+
+static int netback_remove(struct xenbus_device *dev)
+{
+ struct backend_info *be = dev->dev.driver_data;
+
+ netback_remove_accelerators(be, dev);
+
+ if (be->netif) {
+ kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
+ netif_disconnect(be->netif);
+ be->netif = NULL;
+ }
+ kfree(be);
+ dev->dev.driver_data = NULL;
+ return 0;
+}
+
+
+/**
+ * Entry point to this code when a new device is created. Allocate the basic
+ * structures and switch to InitWait.
+ */
+static int netback_probe(struct xenbus_device *dev,
+ const struct xenbus_device_id *id)
+{
+ const char *message;
+ struct xenbus_transaction xbt;
+ int err;
+ int sg;
+ struct backend_info *be = kzalloc(sizeof(struct backend_info),
+ GFP_KERNEL);
+ if (!be) {
+ xenbus_dev_fatal(dev, -ENOMEM,
+ "allocating backend structure");
+ return -ENOMEM;
+ }
+
+ be->dev = dev;
+ dev->dev.driver_data = be;
+
+ sg = 1;
+ if (netbk_copy_skb_mode == NETBK_ALWAYS_COPY_SKB)
+ sg = 0;
+
+ do {
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ xenbus_dev_fatal(dev, err, "starting transaction");
+ goto fail;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg);
+ if (err) {
+ message = "writing feature-sg";
+ goto abort_transaction;
+ }
+
+ err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4",
+ "%d", sg);
+ if (err) {
+ message = "writing feature-gso-tcpv4";
+ goto abort_transaction;
+ }
+
+ /* We support rx-copy path. */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-rx-copy", "%d", 1);
+ if (err) {
+ message = "writing feature-rx-copy";
+ goto abort_transaction;
+ }
+
+ /*
+ * We don't support rx-flip path (except old guests who don't
+ * grok this feature flag).
+ */
+ err = xenbus_printf(xbt, dev->nodename,
+ "feature-rx-flip", "%d", 0);
+ if (err) {
+ message = "writing feature-rx-flip";
+ goto abort_transaction;
+ }
+
+ err = xenbus_transaction_end(xbt, 0);
+ } while (err == -EAGAIN);
+
+ if (err) {
+ xenbus_dev_fatal(dev, err, "completing transaction");
+ goto fail;
+ }
+
+ netback_probe_accelerators(be, dev);
+
+ err = xenbus_switch_state(dev, XenbusStateInitWait);
+ if (err)
+ goto fail;
+
+ /* This kicks hotplug scripts, so do it immediately. */
+ backend_create_netif(be);
+
+ return 0;
+
+abort_transaction:
+ xenbus_transaction_end(xbt, 1);
+ xenbus_dev_fatal(dev, err, "%s", message);
+fail:
+ DPRINTK("failed");
+ netback_remove(dev);
+ return err;
+}
+
+
+/**
+ * Handle the creation of the hotplug script environment. We add the script
+ * and vif variables to the environment, for the benefit of the vif-* hotplug
+ * scripts.
+ */
+static int netback_uevent(struct xenbus_device *xdev, char **envp,
+ int num_envp, char *buffer, int buffer_size)
+{
+ struct backend_info *be = xdev->dev.driver_data;
+ netif_t *netif = be->netif;
+ int i = 0, length = 0;
+ char *val;
+
+ DPRINTK("netback_uevent");
+
+ val = xenbus_read(XBT_NIL, xdev->nodename, "script", NULL);
+ if (IS_ERR(val)) {
+ int err = PTR_ERR(val);
+ xenbus_dev_fatal(xdev, err, "reading script");
+ return err;
+ }
+ else {
+ add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
+ &length, "script=%s", val);
+ kfree(val);
+ }
+
+ add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
+ "vif=%s", netif->dev->name);
+
+ envp[i] = NULL;
+
+ return 0;
+}
+
+
+static void backend_create_netif(struct backend_info *be)
+{
+ int err;
+ long handle;
+ struct xenbus_device *dev = be->dev;
+
+ if (be->netif != NULL)
+ return;
+
+ err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
+ if (err != 1) {
+ xenbus_dev_fatal(dev, err, "reading handle");
+ return;
+ }
+
+ be->netif = netif_alloc(dev->otherend_id, handle);
+ if (IS_ERR(be->netif)) {
+ err = PTR_ERR(be->netif);
+ be->netif = NULL;
+ xenbus_dev_fatal(dev, err, "creating interface");
+ return;
+ }
+
+ kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
+}
+
+
+/**
+ * Callback received when the frontend's state changes.
+ */
+static void frontend_changed(struct xenbus_device *dev,
+ enum xenbus_state frontend_state)
+{
+ struct backend_info *be = dev->dev.driver_data;
+
+ DPRINTK("%s", xenbus_strstate(frontend_state));
+
+ be->frontend_state = frontend_state;
+
+ switch (frontend_state) {
+ case XenbusStateInitialising:
+ if (dev->state == XenbusStateClosed) {
+ printk(KERN_INFO "%s: %s: prepare for reconnect\n",
+ __FUNCTION__, dev->nodename);
+ xenbus_switch_state(dev, XenbusStateInitWait);
+ }
+ break;
+
+ case XenbusStateInitialised:
+ break;
+
+ case XenbusStateConnected:
+ if (dev->state == XenbusStateConnected)
+ break;
+ backend_create_netif(be);
+ if (be->netif)
+ connect(be);
+ break;
+
+ case XenbusStateClosing:
+ if (be->netif) {
+ kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
+ netif_disconnect(be->netif);
+ be->netif = NULL;
+ }
+ xenbus_switch_state(dev, XenbusStateClosing);
+ break;
+
+ case XenbusStateClosed:
+ xenbus_switch_state(dev, XenbusStateClosed);
+ if (xenbus_dev_is_online(dev))
+ break;
+ /* fall through if not online */
+ case XenbusStateUnknown:
+ device_unregister(&dev->dev);
+ break;
+
+ default:
+ xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
+ frontend_state);
+ break;
+ }
+}
+
+
+static void xen_net_read_rate(struct xenbus_device *dev,
+ unsigned long *bytes, unsigned long *usec)
+{
+ char *s, *e;
+ unsigned long b, u;
+ char *ratestr;
+
+ /* Default to unlimited bandwidth. */
+ *bytes = ~0UL;
+ *usec = 0;
+
+ ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
+ if (IS_ERR(ratestr))
+ return;
+
+ s = ratestr;
+ b = simple_strtoul(s, &e, 10);
+ if ((s == e) || (*e != ','))
+ goto fail;
+
+ s = e + 1;
+ u = simple_strtoul(s, &e, 10);
+ if ((s == e) || (*e != '\0'))
+ goto fail;
+
+ *bytes = b;
+ *usec = u;
+
+ kfree(ratestr);
+ return;
+
+ fail:
+ WPRINTK("Failed to parse network rate limit. Traffic unlimited.\n");
+ kfree(ratestr);
+}
+
+static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[])
+{
+ char *s, *e, *macstr;
+ int i;
+
+ macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
+ if (IS_ERR(macstr))
+ return PTR_ERR(macstr);
+
+ for (i = 0; i < ETH_ALEN; i++) {
+ mac[i] = simple_strtoul(s, &e, 16);
+ if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) {
+ kfree(macstr);
+ return -ENOENT;
+ }
+ s = e+1;
+ }
+
+ kfree(macstr);
+ return 0;
+}
+
+static void connect(struct backend_info *be)
+{
+ int err;
+ struct xenbus_device *dev = be->dev;
+
+ err = connect_rings(be);
+ if (err)
+ return;
+
+ err = xen_net_read_mac(dev, be->netif->fe_dev_addr);
+ if (err) {
+ xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
+ return;
+ }
+
+ xen_net_read_rate(dev, &be->netif->credit_bytes,
+ &be->netif->credit_usec);
+ be->netif->remaining_credit = be->netif->credit_bytes;
+
+ xenbus_switch_state(dev, XenbusStateConnected);
+
+ netif_wake_queue(be->netif->dev);
+}
+
+
+static int connect_rings(struct backend_info *be)
+{
+ struct xenbus_device *dev = be->dev;
+ unsigned long tx_ring_ref, rx_ring_ref;
+ unsigned int evtchn, rx_copy;
+ int err;
+ int val;
+
+ DPRINTK("");
+
+ err = xenbus_gather(XBT_NIL, dev->otherend,
+ "tx-ring-ref", "%lu", &tx_ring_ref,
+ "rx-ring-ref", "%lu", &rx_ring_ref,
+ "event-channel", "%u", &evtchn, NULL);
+ if (err) {
+ xenbus_dev_fatal(dev, err,
+ "reading %s/ring-ref and event-channel",
+ dev->otherend);
+ return err;
+ }
+
+ err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u",
+ &rx_copy);
+ if (err == -ENOENT) {
+ err = 0;
+ rx_copy = 0;
+ }
+ if (err < 0) {
+ xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy",
+ dev->otherend);
+ return err;
+ }
+ be->netif->copying_receiver = !!rx_copy;
+
+ if (be->netif->dev->tx_queue_len != 0) {
+ if (xenbus_scanf(XBT_NIL, dev->otherend,
+ "feature-rx-notify", "%d", &val) < 0)
+ val = 0;
+ if (val)
+ be->netif->can_queue = 1;
+ else
+ /* Must be non-zero for pfifo_fast to work. */
+ be->netif->dev->tx_queue_len = 1;
+ }
+
+ if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg", "%d", &val) < 0)
+ val = 0;
+ if (val) {
+ be->netif->features |= NETIF_F_SG;
+ be->netif->dev->features |= NETIF_F_SG;
+ }
+
+ if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4", "%d",
+ &val) < 0)
+ val = 0;
+ if (val) {
+ be->netif->features |= NETIF_F_TSO;
+ be->netif->dev->features |= NETIF_F_TSO;
+ }
+
+ if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-no-csum-offload",
+ "%d", &val) < 0)
+ val = 0;
+ if (val) {
+ be->netif->features &= ~NETIF_F_IP_CSUM;
+ be->netif->dev->features &= ~NETIF_F_IP_CSUM;
+ }
+
+ /* Map the shared frame, irq etc. */
+ err = netif_map(be->netif, tx_ring_ref, rx_ring_ref, evtchn);
+ if (err) {
+ xenbus_dev_fatal(dev, err,
+ "mapping shared-frames %lu/%lu port %u",
+ tx_ring_ref, rx_ring_ref, evtchn);
+ return err;
+ }
+ return 0;
+}
+
+
+/* ** Driver Registration ** */
+
+
+static const struct xenbus_device_id netback_ids[] = {
+ { "vif" },
+ { "" }
+};
+
+
+static struct xenbus_driver netback = {
+ .name = "vif",
+ .owner = THIS_MODULE,
+ .ids = netback_ids,
+ .probe = netback_probe,
+ .remove = netback_remove,
+ .uevent = netback_uevent,
+ .otherend_changed = frontend_changed,
+};
+
+
+void netif_xenbus_init(void)
+{
+ xenbus_register_backend(&netback);
+}
projects / people / ssmith / netchannel2-pvops.git / commitdiff