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![Jeremy Fitzhardinge](/assets/img/avatar_default.png)
Keep tx and rx elements separate on different cachelines to prevent bouncing. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Acked-by: Jeff Garzik <jgarzik@pobox.com> Cc: Stephen Hemminger <shemminger@linux-foundation.org> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Jeff Garzik <jeff@garzik.org>
1816 lines
44 KiB
C
1816 lines
44 KiB
C
/*
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* Virtual network driver for conversing with remote driver backends.
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*
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* Copyright (c) 2002-2005, K A Fraser
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* Copyright (c) 2005, XenSource Ltd
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation; or, when distributed
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* separately from the Linux kernel or incorporated into other
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* software packages, subject to the following license:
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this source file (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use, copy, modify,
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* merge, publish, distribute, sublicense, and/or sell copies of the Software,
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* and to permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/skbuff.h>
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#include <linux/ethtool.h>
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#include <linux/if_ether.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/moduleparam.h>
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#include <linux/mm.h>
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#include <net/ip.h>
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#include <xen/xenbus.h>
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#include <xen/events.h>
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#include <xen/page.h>
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#include <xen/grant_table.h>
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#include <xen/interface/io/netif.h>
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#include <xen/interface/memory.h>
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#include <xen/interface/grant_table.h>
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static struct ethtool_ops xennet_ethtool_ops;
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struct netfront_cb {
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struct page *page;
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unsigned offset;
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};
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#define NETFRONT_SKB_CB(skb) ((struct netfront_cb *)((skb)->cb))
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#define RX_COPY_THRESHOLD 256
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#define GRANT_INVALID_REF 0
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#define NET_TX_RING_SIZE __RING_SIZE((struct xen_netif_tx_sring *)0, PAGE_SIZE)
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#define NET_RX_RING_SIZE __RING_SIZE((struct xen_netif_rx_sring *)0, PAGE_SIZE)
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#define TX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256)
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struct netfront_info {
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struct list_head list;
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struct net_device *netdev;
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struct napi_struct napi;
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unsigned int evtchn;
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struct xenbus_device *xbdev;
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spinlock_t tx_lock;
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struct xen_netif_tx_front_ring tx;
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int tx_ring_ref;
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/*
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* {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries
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* are linked from tx_skb_freelist through skb_entry.link.
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*
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* NB. Freelist index entries are always going to be less than
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* PAGE_OFFSET, whereas pointers to skbs will always be equal or
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* greater than PAGE_OFFSET: we use this property to distinguish
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* them.
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*/
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union skb_entry {
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struct sk_buff *skb;
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unsigned link;
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} tx_skbs[NET_TX_RING_SIZE];
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grant_ref_t gref_tx_head;
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grant_ref_t grant_tx_ref[NET_TX_RING_SIZE];
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unsigned tx_skb_freelist;
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spinlock_t rx_lock ____cacheline_aligned_in_smp;
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struct xen_netif_rx_front_ring rx;
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int rx_ring_ref;
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/* Receive-ring batched refills. */
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#define RX_MIN_TARGET 8
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#define RX_DFL_MIN_TARGET 64
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#define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256)
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unsigned rx_min_target, rx_max_target, rx_target;
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struct sk_buff_head rx_batch;
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struct timer_list rx_refill_timer;
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struct sk_buff *rx_skbs[NET_RX_RING_SIZE];
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grant_ref_t gref_rx_head;
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grant_ref_t grant_rx_ref[NET_RX_RING_SIZE];
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unsigned long rx_pfn_array[NET_RX_RING_SIZE];
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struct multicall_entry rx_mcl[NET_RX_RING_SIZE+1];
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struct mmu_update rx_mmu[NET_RX_RING_SIZE];
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};
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struct netfront_rx_info {
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struct xen_netif_rx_response rx;
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struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
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};
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/*
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* Access macros for acquiring freeing slots in tx_skbs[].
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*/
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static void add_id_to_freelist(unsigned *head, union skb_entry *list,
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unsigned short id)
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{
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list[id].link = *head;
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*head = id;
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}
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static unsigned short get_id_from_freelist(unsigned *head,
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union skb_entry *list)
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{
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unsigned int id = *head;
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*head = list[id].link;
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return id;
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}
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static int xennet_rxidx(RING_IDX idx)
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{
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return idx & (NET_RX_RING_SIZE - 1);
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}
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static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np,
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RING_IDX ri)
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{
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int i = xennet_rxidx(ri);
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struct sk_buff *skb = np->rx_skbs[i];
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np->rx_skbs[i] = NULL;
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return skb;
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}
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static grant_ref_t xennet_get_rx_ref(struct netfront_info *np,
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RING_IDX ri)
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{
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int i = xennet_rxidx(ri);
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grant_ref_t ref = np->grant_rx_ref[i];
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np->grant_rx_ref[i] = GRANT_INVALID_REF;
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return ref;
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}
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#ifdef CONFIG_SYSFS
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static int xennet_sysfs_addif(struct net_device *netdev);
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static void xennet_sysfs_delif(struct net_device *netdev);
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#else /* !CONFIG_SYSFS */
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#define xennet_sysfs_addif(dev) (0)
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#define xennet_sysfs_delif(dev) do { } while (0)
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#endif
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static int xennet_can_sg(struct net_device *dev)
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{
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return dev->features & NETIF_F_SG;
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}
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static void rx_refill_timeout(unsigned long data)
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{
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struct net_device *dev = (struct net_device *)data;
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struct netfront_info *np = netdev_priv(dev);
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netif_rx_schedule(dev, &np->napi);
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}
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static int netfront_tx_slot_available(struct netfront_info *np)
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{
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return ((np->tx.req_prod_pvt - np->tx.rsp_cons) <
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(TX_MAX_TARGET - MAX_SKB_FRAGS - 2));
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}
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static void xennet_maybe_wake_tx(struct net_device *dev)
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{
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struct netfront_info *np = netdev_priv(dev);
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if (unlikely(netif_queue_stopped(dev)) &&
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netfront_tx_slot_available(np) &&
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likely(netif_running(dev)))
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netif_wake_queue(dev);
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}
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static void xennet_alloc_rx_buffers(struct net_device *dev)
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{
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unsigned short id;
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struct netfront_info *np = netdev_priv(dev);
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struct sk_buff *skb;
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struct page *page;
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int i, batch_target, notify;
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RING_IDX req_prod = np->rx.req_prod_pvt;
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grant_ref_t ref;
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unsigned long pfn;
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void *vaddr;
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struct xen_netif_rx_request *req;
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if (unlikely(!netif_carrier_ok(dev)))
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return;
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/*
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* Allocate skbuffs greedily, even though we batch updates to the
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* receive ring. This creates a less bursty demand on the memory
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* allocator, so should reduce the chance of failed allocation requests
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* both for ourself and for other kernel subsystems.
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*/
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batch_target = np->rx_target - (req_prod - np->rx.rsp_cons);
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for (i = skb_queue_len(&np->rx_batch); i < batch_target; i++) {
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skb = __netdev_alloc_skb(dev, RX_COPY_THRESHOLD,
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GFP_ATOMIC | __GFP_NOWARN);
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if (unlikely(!skb))
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goto no_skb;
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page = alloc_page(GFP_ATOMIC | __GFP_NOWARN);
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if (!page) {
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kfree_skb(skb);
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no_skb:
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/* Any skbuffs queued for refill? Force them out. */
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if (i != 0)
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goto refill;
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/* Could not allocate any skbuffs. Try again later. */
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mod_timer(&np->rx_refill_timer,
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jiffies + (HZ/10));
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break;
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}
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skb_shinfo(skb)->frags[0].page = page;
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skb_shinfo(skb)->nr_frags = 1;
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__skb_queue_tail(&np->rx_batch, skb);
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}
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/* Is the batch large enough to be worthwhile? */
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if (i < (np->rx_target/2)) {
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if (req_prod > np->rx.sring->req_prod)
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goto push;
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return;
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}
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/* Adjust our fill target if we risked running out of buffers. */
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if (((req_prod - np->rx.sring->rsp_prod) < (np->rx_target / 4)) &&
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((np->rx_target *= 2) > np->rx_max_target))
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np->rx_target = np->rx_max_target;
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refill:
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for (i = 0; ; i++) {
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skb = __skb_dequeue(&np->rx_batch);
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if (skb == NULL)
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break;
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skb->dev = dev;
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id = xennet_rxidx(req_prod + i);
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BUG_ON(np->rx_skbs[id]);
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np->rx_skbs[id] = skb;
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ref = gnttab_claim_grant_reference(&np->gref_rx_head);
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BUG_ON((signed short)ref < 0);
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np->grant_rx_ref[id] = ref;
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pfn = page_to_pfn(skb_shinfo(skb)->frags[0].page);
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vaddr = page_address(skb_shinfo(skb)->frags[0].page);
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req = RING_GET_REQUEST(&np->rx, req_prod + i);
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gnttab_grant_foreign_access_ref(ref,
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np->xbdev->otherend_id,
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pfn_to_mfn(pfn),
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0);
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req->id = id;
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req->gref = ref;
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}
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wmb(); /* barrier so backend seens requests */
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/* Above is a suitable barrier to ensure backend will see requests. */
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np->rx.req_prod_pvt = req_prod + i;
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push:
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RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->rx, notify);
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if (notify)
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notify_remote_via_irq(np->netdev->irq);
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}
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static int xennet_open(struct net_device *dev)
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{
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struct netfront_info *np = netdev_priv(dev);
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napi_enable(&np->napi);
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spin_lock_bh(&np->rx_lock);
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if (netif_carrier_ok(dev)) {
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xennet_alloc_rx_buffers(dev);
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np->rx.sring->rsp_event = np->rx.rsp_cons + 1;
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if (RING_HAS_UNCONSUMED_RESPONSES(&np->rx))
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netif_rx_schedule(dev, &np->napi);
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}
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spin_unlock_bh(&np->rx_lock);
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xennet_maybe_wake_tx(dev);
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return 0;
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}
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static void xennet_tx_buf_gc(struct net_device *dev)
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{
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RING_IDX cons, prod;
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unsigned short id;
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struct netfront_info *np = netdev_priv(dev);
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struct sk_buff *skb;
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BUG_ON(!netif_carrier_ok(dev));
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do {
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prod = np->tx.sring->rsp_prod;
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rmb(); /* Ensure we see responses up to 'rp'. */
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for (cons = np->tx.rsp_cons; cons != prod; cons++) {
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struct xen_netif_tx_response *txrsp;
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txrsp = RING_GET_RESPONSE(&np->tx, cons);
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if (txrsp->status == NETIF_RSP_NULL)
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continue;
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id = txrsp->id;
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skb = np->tx_skbs[id].skb;
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if (unlikely(gnttab_query_foreign_access(
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np->grant_tx_ref[id]) != 0)) {
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printk(KERN_ALERT "xennet_tx_buf_gc: warning "
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"-- grant still in use by backend "
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"domain.\n");
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BUG();
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}
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gnttab_end_foreign_access_ref(
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np->grant_tx_ref[id], GNTMAP_readonly);
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gnttab_release_grant_reference(
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&np->gref_tx_head, np->grant_tx_ref[id]);
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np->grant_tx_ref[id] = GRANT_INVALID_REF;
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add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs, id);
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dev_kfree_skb_irq(skb);
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}
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|
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np->tx.rsp_cons = prod;
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|
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/*
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* Set a new event, then check for race with update of tx_cons.
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* Note that it is essential to schedule a callback, no matter
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* how few buffers are pending. Even if there is space in the
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* transmit ring, higher layers may be blocked because too much
|
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* data is outstanding: in such cases notification from Xen is
|
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* likely to be the only kick that we'll get.
|
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*/
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np->tx.sring->rsp_event =
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prod + ((np->tx.sring->req_prod - prod) >> 1) + 1;
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mb(); /* update shared area */
|
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} while ((cons == prod) && (prod != np->tx.sring->rsp_prod));
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|
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xennet_maybe_wake_tx(dev);
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}
|
|
|
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static void xennet_make_frags(struct sk_buff *skb, struct net_device *dev,
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struct xen_netif_tx_request *tx)
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{
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struct netfront_info *np = netdev_priv(dev);
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char *data = skb->data;
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unsigned long mfn;
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RING_IDX prod = np->tx.req_prod_pvt;
|
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int frags = skb_shinfo(skb)->nr_frags;
|
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unsigned int offset = offset_in_page(data);
|
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unsigned int len = skb_headlen(skb);
|
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unsigned int id;
|
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grant_ref_t ref;
|
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int i;
|
|
|
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/* While the header overlaps a page boundary (including being
|
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larger than a page), split it it into page-sized chunks. */
|
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while (len > PAGE_SIZE - offset) {
|
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tx->size = PAGE_SIZE - offset;
|
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tx->flags |= NETTXF_more_data;
|
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len -= tx->size;
|
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data += tx->size;
|
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offset = 0;
|
|
|
|
id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs);
|
|
np->tx_skbs[id].skb = skb_get(skb);
|
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tx = RING_GET_REQUEST(&np->tx, prod++);
|
|
tx->id = id;
|
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ref = gnttab_claim_grant_reference(&np->gref_tx_head);
|
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BUG_ON((signed short)ref < 0);
|
|
|
|
mfn = virt_to_mfn(data);
|
|
gnttab_grant_foreign_access_ref(ref, np->xbdev->otherend_id,
|
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mfn, GNTMAP_readonly);
|
|
|
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tx->gref = np->grant_tx_ref[id] = ref;
|
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tx->offset = offset;
|
|
tx->size = len;
|
|
tx->flags = 0;
|
|
}
|
|
|
|
/* Grant backend access to each skb fragment page. */
|
|
for (i = 0; i < frags; i++) {
|
|
skb_frag_t *frag = skb_shinfo(skb)->frags + i;
|
|
|
|
tx->flags |= NETTXF_more_data;
|
|
|
|
id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs);
|
|
np->tx_skbs[id].skb = skb_get(skb);
|
|
tx = RING_GET_REQUEST(&np->tx, prod++);
|
|
tx->id = id;
|
|
ref = gnttab_claim_grant_reference(&np->gref_tx_head);
|
|
BUG_ON((signed short)ref < 0);
|
|
|
|
mfn = pfn_to_mfn(page_to_pfn(frag->page));
|
|
gnttab_grant_foreign_access_ref(ref, np->xbdev->otherend_id,
|
|
mfn, GNTMAP_readonly);
|
|
|
|
tx->gref = np->grant_tx_ref[id] = ref;
|
|
tx->offset = frag->page_offset;
|
|
tx->size = frag->size;
|
|
tx->flags = 0;
|
|
}
|
|
|
|
np->tx.req_prod_pvt = prod;
|
|
}
|
|
|
|
static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
unsigned short id;
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
struct xen_netif_tx_request *tx;
|
|
struct xen_netif_extra_info *extra;
|
|
char *data = skb->data;
|
|
RING_IDX i;
|
|
grant_ref_t ref;
|
|
unsigned long mfn;
|
|
int notify;
|
|
int frags = skb_shinfo(skb)->nr_frags;
|
|
unsigned int offset = offset_in_page(data);
|
|
unsigned int len = skb_headlen(skb);
|
|
|
|
frags += (offset + len + PAGE_SIZE - 1) / PAGE_SIZE;
|
|
if (unlikely(frags > MAX_SKB_FRAGS + 1)) {
|
|
printk(KERN_ALERT "xennet: skb rides the rocket: %d frags\n",
|
|
frags);
|
|
dump_stack();
|
|
goto drop;
|
|
}
|
|
|
|
spin_lock_irq(&np->tx_lock);
|
|
|
|
if (unlikely(!netif_carrier_ok(dev) ||
|
|
(frags > 1 && !xennet_can_sg(dev)) ||
|
|
netif_needs_gso(dev, skb))) {
|
|
spin_unlock_irq(&np->tx_lock);
|
|
goto drop;
|
|
}
|
|
|
|
i = np->tx.req_prod_pvt;
|
|
|
|
id = get_id_from_freelist(&np->tx_skb_freelist, np->tx_skbs);
|
|
np->tx_skbs[id].skb = skb;
|
|
|
|
tx = RING_GET_REQUEST(&np->tx, i);
|
|
|
|
tx->id = id;
|
|
ref = gnttab_claim_grant_reference(&np->gref_tx_head);
|
|
BUG_ON((signed short)ref < 0);
|
|
mfn = virt_to_mfn(data);
|
|
gnttab_grant_foreign_access_ref(
|
|
ref, np->xbdev->otherend_id, mfn, GNTMAP_readonly);
|
|
tx->gref = np->grant_tx_ref[id] = ref;
|
|
tx->offset = offset;
|
|
tx->size = len;
|
|
extra = NULL;
|
|
|
|
tx->flags = 0;
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL)
|
|
/* local packet? */
|
|
tx->flags |= NETTXF_csum_blank | NETTXF_data_validated;
|
|
else if (skb->ip_summed == CHECKSUM_UNNECESSARY)
|
|
/* remote but checksummed. */
|
|
tx->flags |= NETTXF_data_validated;
|
|
|
|
if (skb_shinfo(skb)->gso_size) {
|
|
struct xen_netif_extra_info *gso;
|
|
|
|
gso = (struct xen_netif_extra_info *)
|
|
RING_GET_REQUEST(&np->tx, ++i);
|
|
|
|
if (extra)
|
|
extra->flags |= XEN_NETIF_EXTRA_FLAG_MORE;
|
|
else
|
|
tx->flags |= NETTXF_extra_info;
|
|
|
|
gso->u.gso.size = skb_shinfo(skb)->gso_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;
|
|
extra = gso;
|
|
}
|
|
|
|
np->tx.req_prod_pvt = i + 1;
|
|
|
|
xennet_make_frags(skb, dev, tx);
|
|
tx->size = skb->len;
|
|
|
|
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&np->tx, notify);
|
|
if (notify)
|
|
notify_remote_via_irq(np->netdev->irq);
|
|
|
|
dev->stats.tx_bytes += skb->len;
|
|
dev->stats.tx_packets++;
|
|
|
|
/* Note: It is not safe to access skb after xennet_tx_buf_gc()! */
|
|
xennet_tx_buf_gc(dev);
|
|
|
|
if (!netfront_tx_slot_available(np))
|
|
netif_stop_queue(dev);
|
|
|
|
spin_unlock_irq(&np->tx_lock);
|
|
|
|
return 0;
|
|
|
|
drop:
|
|
dev->stats.tx_dropped++;
|
|
dev_kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
static int xennet_close(struct net_device *dev)
|
|
{
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
netif_stop_queue(np->netdev);
|
|
napi_disable(&np->napi);
|
|
return 0;
|
|
}
|
|
|
|
static void xennet_move_rx_slot(struct netfront_info *np, struct sk_buff *skb,
|
|
grant_ref_t ref)
|
|
{
|
|
int new = xennet_rxidx(np->rx.req_prod_pvt);
|
|
|
|
BUG_ON(np->rx_skbs[new]);
|
|
np->rx_skbs[new] = skb;
|
|
np->grant_rx_ref[new] = ref;
|
|
RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->id = new;
|
|
RING_GET_REQUEST(&np->rx, np->rx.req_prod_pvt)->gref = ref;
|
|
np->rx.req_prod_pvt++;
|
|
}
|
|
|
|
static int xennet_get_extras(struct netfront_info *np,
|
|
struct xen_netif_extra_info *extras,
|
|
RING_IDX rp)
|
|
|
|
{
|
|
struct xen_netif_extra_info *extra;
|
|
struct device *dev = &np->netdev->dev;
|
|
RING_IDX cons = np->rx.rsp_cons;
|
|
int err = 0;
|
|
|
|
do {
|
|
struct sk_buff *skb;
|
|
grant_ref_t ref;
|
|
|
|
if (unlikely(cons + 1 == rp)) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "Missing extra info\n");
|
|
err = -EBADR;
|
|
break;
|
|
}
|
|
|
|
extra = (struct xen_netif_extra_info *)
|
|
RING_GET_RESPONSE(&np->rx, ++cons);
|
|
|
|
if (unlikely(!extra->type ||
|
|
extra->type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "Invalid extra type: %d\n",
|
|
extra->type);
|
|
err = -EINVAL;
|
|
} else {
|
|
memcpy(&extras[extra->type - 1], extra,
|
|
sizeof(*extra));
|
|
}
|
|
|
|
skb = xennet_get_rx_skb(np, cons);
|
|
ref = xennet_get_rx_ref(np, cons);
|
|
xennet_move_rx_slot(np, skb, ref);
|
|
} while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE);
|
|
|
|
np->rx.rsp_cons = cons;
|
|
return err;
|
|
}
|
|
|
|
static int xennet_get_responses(struct netfront_info *np,
|
|
struct netfront_rx_info *rinfo, RING_IDX rp,
|
|
struct sk_buff_head *list)
|
|
{
|
|
struct xen_netif_rx_response *rx = &rinfo->rx;
|
|
struct xen_netif_extra_info *extras = rinfo->extras;
|
|
struct device *dev = &np->netdev->dev;
|
|
RING_IDX cons = np->rx.rsp_cons;
|
|
struct sk_buff *skb = xennet_get_rx_skb(np, cons);
|
|
grant_ref_t ref = xennet_get_rx_ref(np, cons);
|
|
int max = MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD);
|
|
int frags = 1;
|
|
int err = 0;
|
|
unsigned long ret;
|
|
|
|
if (rx->flags & NETRXF_extra_info) {
|
|
err = xennet_get_extras(np, extras, rp);
|
|
cons = np->rx.rsp_cons;
|
|
}
|
|
|
|
for (;;) {
|
|
if (unlikely(rx->status < 0 ||
|
|
rx->offset + rx->status > PAGE_SIZE)) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "rx->offset: %x, size: %u\n",
|
|
rx->offset, rx->status);
|
|
xennet_move_rx_slot(np, skb, ref);
|
|
err = -EINVAL;
|
|
goto next;
|
|
}
|
|
|
|
/*
|
|
* This definitely indicates a bug, either in this driver or in
|
|
* the backend driver. In future this should flag the bad
|
|
* situation to the system controller to reboot the backed.
|
|
*/
|
|
if (ref == GRANT_INVALID_REF) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "Bad rx response id %d.\n",
|
|
rx->id);
|
|
err = -EINVAL;
|
|
goto next;
|
|
}
|
|
|
|
ret = gnttab_end_foreign_access_ref(ref, 0);
|
|
BUG_ON(!ret);
|
|
|
|
gnttab_release_grant_reference(&np->gref_rx_head, ref);
|
|
|
|
__skb_queue_tail(list, skb);
|
|
|
|
next:
|
|
if (!(rx->flags & NETRXF_more_data))
|
|
break;
|
|
|
|
if (cons + frags == rp) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "Need more frags\n");
|
|
err = -ENOENT;
|
|
break;
|
|
}
|
|
|
|
rx = RING_GET_RESPONSE(&np->rx, cons + frags);
|
|
skb = xennet_get_rx_skb(np, cons + frags);
|
|
ref = xennet_get_rx_ref(np, cons + frags);
|
|
frags++;
|
|
}
|
|
|
|
if (unlikely(frags > max)) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "Too many frags\n");
|
|
err = -E2BIG;
|
|
}
|
|
|
|
if (unlikely(err))
|
|
np->rx.rsp_cons = cons + frags;
|
|
|
|
return err;
|
|
}
|
|
|
|
static int xennet_set_skb_gso(struct sk_buff *skb,
|
|
struct xen_netif_extra_info *gso)
|
|
{
|
|
if (!gso->u.gso.size) {
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING "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) {
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING "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;
|
|
}
|
|
|
|
static RING_IDX xennet_fill_frags(struct netfront_info *np,
|
|
struct sk_buff *skb,
|
|
struct sk_buff_head *list)
|
|
{
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
int nr_frags = shinfo->nr_frags;
|
|
RING_IDX cons = np->rx.rsp_cons;
|
|
skb_frag_t *frag = shinfo->frags + nr_frags;
|
|
struct sk_buff *nskb;
|
|
|
|
while ((nskb = __skb_dequeue(list))) {
|
|
struct xen_netif_rx_response *rx =
|
|
RING_GET_RESPONSE(&np->rx, ++cons);
|
|
|
|
frag->page = skb_shinfo(nskb)->frags[0].page;
|
|
frag->page_offset = rx->offset;
|
|
frag->size = rx->status;
|
|
|
|
skb->data_len += rx->status;
|
|
|
|
skb_shinfo(nskb)->nr_frags = 0;
|
|
kfree_skb(nskb);
|
|
|
|
frag++;
|
|
nr_frags++;
|
|
}
|
|
|
|
shinfo->nr_frags = nr_frags;
|
|
return cons;
|
|
}
|
|
|
|
static int skb_checksum_setup(struct sk_buff *skb)
|
|
{
|
|
struct iphdr *iph;
|
|
unsigned char *th;
|
|
int err = -EPROTO;
|
|
|
|
if (skb->protocol != htons(ETH_P_IP))
|
|
goto out;
|
|
|
|
iph = (void *)skb->data;
|
|
th = skb->data + 4 * iph->ihl;
|
|
if (th >= skb_tail_pointer(skb))
|
|
goto out;
|
|
|
|
skb->csum_start = th - skb->head;
|
|
switch (iph->protocol) {
|
|
case IPPROTO_TCP:
|
|
skb->csum_offset = offsetof(struct tcphdr, check);
|
|
break;
|
|
case IPPROTO_UDP:
|
|
skb->csum_offset = offsetof(struct udphdr, check);
|
|
break;
|
|
default:
|
|
if (net_ratelimit())
|
|
printk(KERN_ERR "Attempting to checksum a non-"
|
|
"TCP/UDP packet, dropping a protocol"
|
|
" %d packet", iph->protocol);
|
|
goto out;
|
|
}
|
|
|
|
if ((th + skb->csum_offset + 2) > skb_tail_pointer(skb))
|
|
goto out;
|
|
|
|
err = 0;
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static int handle_incoming_queue(struct net_device *dev,
|
|
struct sk_buff_head *rxq)
|
|
{
|
|
int packets_dropped = 0;
|
|
struct sk_buff *skb;
|
|
|
|
while ((skb = __skb_dequeue(rxq)) != NULL) {
|
|
struct page *page = NETFRONT_SKB_CB(skb)->page;
|
|
void *vaddr = page_address(page);
|
|
unsigned offset = NETFRONT_SKB_CB(skb)->offset;
|
|
|
|
memcpy(skb->data, vaddr + offset,
|
|
skb_headlen(skb));
|
|
|
|
if (page != skb_shinfo(skb)->frags[0].page)
|
|
__free_page(page);
|
|
|
|
/* Ethernet work: Delayed to here as it peeks the header. */
|
|
skb->protocol = eth_type_trans(skb, dev);
|
|
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL) {
|
|
if (skb_checksum_setup(skb)) {
|
|
kfree_skb(skb);
|
|
packets_dropped++;
|
|
dev->stats.rx_errors++;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
dev->stats.rx_packets++;
|
|
dev->stats.rx_bytes += skb->len;
|
|
|
|
/* Pass it up. */
|
|
netif_receive_skb(skb);
|
|
dev->last_rx = jiffies;
|
|
}
|
|
|
|
return packets_dropped;
|
|
}
|
|
|
|
static int xennet_poll(struct napi_struct *napi, int budget)
|
|
{
|
|
struct netfront_info *np = container_of(napi, struct netfront_info, napi);
|
|
struct net_device *dev = np->netdev;
|
|
struct sk_buff *skb;
|
|
struct netfront_rx_info rinfo;
|
|
struct xen_netif_rx_response *rx = &rinfo.rx;
|
|
struct xen_netif_extra_info *extras = rinfo.extras;
|
|
RING_IDX i, rp;
|
|
int work_done;
|
|
struct sk_buff_head rxq;
|
|
struct sk_buff_head errq;
|
|
struct sk_buff_head tmpq;
|
|
unsigned long flags;
|
|
unsigned int len;
|
|
int err;
|
|
|
|
spin_lock(&np->rx_lock);
|
|
|
|
if (unlikely(!netif_carrier_ok(dev))) {
|
|
spin_unlock(&np->rx_lock);
|
|
return 0;
|
|
}
|
|
|
|
skb_queue_head_init(&rxq);
|
|
skb_queue_head_init(&errq);
|
|
skb_queue_head_init(&tmpq);
|
|
|
|
rp = np->rx.sring->rsp_prod;
|
|
rmb(); /* Ensure we see queued responses up to 'rp'. */
|
|
|
|
i = np->rx.rsp_cons;
|
|
work_done = 0;
|
|
while ((i != rp) && (work_done < budget)) {
|
|
memcpy(rx, RING_GET_RESPONSE(&np->rx, i), sizeof(*rx));
|
|
memset(extras, 0, sizeof(rinfo.extras));
|
|
|
|
err = xennet_get_responses(np, &rinfo, rp, &tmpq);
|
|
|
|
if (unlikely(err)) {
|
|
err:
|
|
while ((skb = __skb_dequeue(&tmpq)))
|
|
__skb_queue_tail(&errq, skb);
|
|
dev->stats.rx_errors++;
|
|
i = np->rx.rsp_cons;
|
|
continue;
|
|
}
|
|
|
|
skb = __skb_dequeue(&tmpq);
|
|
|
|
if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) {
|
|
struct xen_netif_extra_info *gso;
|
|
gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1];
|
|
|
|
if (unlikely(xennet_set_skb_gso(skb, gso))) {
|
|
__skb_queue_head(&tmpq, skb);
|
|
np->rx.rsp_cons += skb_queue_len(&tmpq);
|
|
goto err;
|
|
}
|
|
}
|
|
|
|
NETFRONT_SKB_CB(skb)->page = skb_shinfo(skb)->frags[0].page;
|
|
NETFRONT_SKB_CB(skb)->offset = rx->offset;
|
|
|
|
len = rx->status;
|
|
if (len > RX_COPY_THRESHOLD)
|
|
len = RX_COPY_THRESHOLD;
|
|
skb_put(skb, len);
|
|
|
|
if (rx->status > len) {
|
|
skb_shinfo(skb)->frags[0].page_offset =
|
|
rx->offset + len;
|
|
skb_shinfo(skb)->frags[0].size = rx->status - len;
|
|
skb->data_len = rx->status - len;
|
|
} else {
|
|
skb_shinfo(skb)->frags[0].page = NULL;
|
|
skb_shinfo(skb)->nr_frags = 0;
|
|
}
|
|
|
|
i = xennet_fill_frags(np, skb, &tmpq);
|
|
|
|
/*
|
|
* Truesize approximates the size of true data plus
|
|
* any supervisor overheads. Adding hypervisor
|
|
* overheads has been shown to significantly reduce
|
|
* achievable bandwidth with the default receive
|
|
* buffer size. It is therefore not wise to account
|
|
* for it here.
|
|
*
|
|
* After alloc_skb(RX_COPY_THRESHOLD), truesize is set
|
|
* to RX_COPY_THRESHOLD + the supervisor
|
|
* overheads. Here, we add the size of the data pulled
|
|
* in xennet_fill_frags().
|
|
*
|
|
* We also adjust for any unused space in the main
|
|
* data area by subtracting (RX_COPY_THRESHOLD -
|
|
* len). This is especially important with drivers
|
|
* which split incoming packets into header and data,
|
|
* using only 66 bytes of the main data area (see the
|
|
* e1000 driver for example.) On such systems,
|
|
* without this last adjustement, our achievable
|
|
* receive throughout using the standard receive
|
|
* buffer size was cut by 25%(!!!).
|
|
*/
|
|
skb->truesize += skb->data_len - (RX_COPY_THRESHOLD - len);
|
|
skb->len += skb->data_len;
|
|
|
|
if (rx->flags & NETRXF_csum_blank)
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
else if (rx->flags & NETRXF_data_validated)
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
__skb_queue_tail(&rxq, skb);
|
|
|
|
np->rx.rsp_cons = ++i;
|
|
work_done++;
|
|
}
|
|
|
|
while ((skb = __skb_dequeue(&errq)))
|
|
kfree_skb(skb);
|
|
|
|
work_done -= handle_incoming_queue(dev, &rxq);
|
|
|
|
/* If we get a callback with very few responses, reduce fill target. */
|
|
/* NB. Note exponential increase, linear decrease. */
|
|
if (((np->rx.req_prod_pvt - np->rx.sring->rsp_prod) >
|
|
((3*np->rx_target) / 4)) &&
|
|
(--np->rx_target < np->rx_min_target))
|
|
np->rx_target = np->rx_min_target;
|
|
|
|
xennet_alloc_rx_buffers(dev);
|
|
|
|
if (work_done < budget) {
|
|
int more_to_do = 0;
|
|
|
|
local_irq_save(flags);
|
|
|
|
RING_FINAL_CHECK_FOR_RESPONSES(&np->rx, more_to_do);
|
|
if (!more_to_do)
|
|
__netif_rx_complete(dev, napi);
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
spin_unlock(&np->rx_lock);
|
|
|
|
return work_done;
|
|
}
|
|
|
|
static int xennet_change_mtu(struct net_device *dev, int mtu)
|
|
{
|
|
int max = xennet_can_sg(dev) ? 65535 - ETH_HLEN : ETH_DATA_LEN;
|
|
|
|
if (mtu > max)
|
|
return -EINVAL;
|
|
dev->mtu = mtu;
|
|
return 0;
|
|
}
|
|
|
|
static void xennet_release_tx_bufs(struct netfront_info *np)
|
|
{
|
|
struct sk_buff *skb;
|
|
int i;
|
|
|
|
for (i = 0; i < NET_TX_RING_SIZE; i++) {
|
|
/* Skip over entries which are actually freelist references */
|
|
if ((unsigned long)np->tx_skbs[i].skb < PAGE_OFFSET)
|
|
continue;
|
|
|
|
skb = np->tx_skbs[i].skb;
|
|
gnttab_end_foreign_access_ref(np->grant_tx_ref[i],
|
|
GNTMAP_readonly);
|
|
gnttab_release_grant_reference(&np->gref_tx_head,
|
|
np->grant_tx_ref[i]);
|
|
np->grant_tx_ref[i] = GRANT_INVALID_REF;
|
|
add_id_to_freelist(&np->tx_skb_freelist, np->tx_skbs, i);
|
|
dev_kfree_skb_irq(skb);
|
|
}
|
|
}
|
|
|
|
static void xennet_release_rx_bufs(struct netfront_info *np)
|
|
{
|
|
struct mmu_update *mmu = np->rx_mmu;
|
|
struct multicall_entry *mcl = np->rx_mcl;
|
|
struct sk_buff_head free_list;
|
|
struct sk_buff *skb;
|
|
unsigned long mfn;
|
|
int xfer = 0, noxfer = 0, unused = 0;
|
|
int id, ref;
|
|
|
|
dev_warn(&np->netdev->dev, "%s: fix me for copying receiver.\n",
|
|
__func__);
|
|
return;
|
|
|
|
skb_queue_head_init(&free_list);
|
|
|
|
spin_lock_bh(&np->rx_lock);
|
|
|
|
for (id = 0; id < NET_RX_RING_SIZE; id++) {
|
|
ref = np->grant_rx_ref[id];
|
|
if (ref == GRANT_INVALID_REF) {
|
|
unused++;
|
|
continue;
|
|
}
|
|
|
|
skb = np->rx_skbs[id];
|
|
mfn = gnttab_end_foreign_transfer_ref(ref);
|
|
gnttab_release_grant_reference(&np->gref_rx_head, ref);
|
|
np->grant_rx_ref[id] = GRANT_INVALID_REF;
|
|
|
|
if (0 == mfn) {
|
|
skb_shinfo(skb)->nr_frags = 0;
|
|
dev_kfree_skb(skb);
|
|
noxfer++;
|
|
continue;
|
|
}
|
|
|
|
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
|
|
/* Remap the page. */
|
|
struct page *page = skb_shinfo(skb)->frags[0].page;
|
|
unsigned long pfn = page_to_pfn(page);
|
|
void *vaddr = page_address(page);
|
|
|
|
MULTI_update_va_mapping(mcl, (unsigned long)vaddr,
|
|
mfn_pte(mfn, PAGE_KERNEL),
|
|
0);
|
|
mcl++;
|
|
mmu->ptr = ((u64)mfn << PAGE_SHIFT)
|
|
| MMU_MACHPHYS_UPDATE;
|
|
mmu->val = pfn;
|
|
mmu++;
|
|
|
|
set_phys_to_machine(pfn, mfn);
|
|
}
|
|
__skb_queue_tail(&free_list, skb);
|
|
xfer++;
|
|
}
|
|
|
|
dev_info(&np->netdev->dev, "%s: %d xfer, %d noxfer, %d unused\n",
|
|
__func__, xfer, noxfer, unused);
|
|
|
|
if (xfer) {
|
|
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
|
|
/* Do all the remapping work and M2P updates. */
|
|
MULTI_mmu_update(mcl, np->rx_mmu, mmu - np->rx_mmu,
|
|
0, DOMID_SELF);
|
|
mcl++;
|
|
HYPERVISOR_multicall(np->rx_mcl, mcl - np->rx_mcl);
|
|
}
|
|
}
|
|
|
|
while ((skb = __skb_dequeue(&free_list)) != NULL)
|
|
dev_kfree_skb(skb);
|
|
|
|
spin_unlock_bh(&np->rx_lock);
|
|
}
|
|
|
|
static void xennet_uninit(struct net_device *dev)
|
|
{
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
xennet_release_tx_bufs(np);
|
|
xennet_release_rx_bufs(np);
|
|
gnttab_free_grant_references(np->gref_tx_head);
|
|
gnttab_free_grant_references(np->gref_rx_head);
|
|
}
|
|
|
|
static struct net_device * __devinit xennet_create_dev(struct xenbus_device *dev)
|
|
{
|
|
int i, err;
|
|
struct net_device *netdev;
|
|
struct netfront_info *np;
|
|
|
|
netdev = alloc_etherdev(sizeof(struct netfront_info));
|
|
if (!netdev) {
|
|
printk(KERN_WARNING "%s> alloc_etherdev failed.\n",
|
|
__func__);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
np = netdev_priv(netdev);
|
|
np->xbdev = dev;
|
|
|
|
spin_lock_init(&np->tx_lock);
|
|
spin_lock_init(&np->rx_lock);
|
|
|
|
skb_queue_head_init(&np->rx_batch);
|
|
np->rx_target = RX_DFL_MIN_TARGET;
|
|
np->rx_min_target = RX_DFL_MIN_TARGET;
|
|
np->rx_max_target = RX_MAX_TARGET;
|
|
|
|
init_timer(&np->rx_refill_timer);
|
|
np->rx_refill_timer.data = (unsigned long)netdev;
|
|
np->rx_refill_timer.function = rx_refill_timeout;
|
|
|
|
/* Initialise tx_skbs as a free chain containing every entry. */
|
|
np->tx_skb_freelist = 0;
|
|
for (i = 0; i < NET_TX_RING_SIZE; i++) {
|
|
np->tx_skbs[i].link = i+1;
|
|
np->grant_tx_ref[i] = GRANT_INVALID_REF;
|
|
}
|
|
|
|
/* Clear out rx_skbs */
|
|
for (i = 0; i < NET_RX_RING_SIZE; i++) {
|
|
np->rx_skbs[i] = NULL;
|
|
np->grant_rx_ref[i] = GRANT_INVALID_REF;
|
|
}
|
|
|
|
/* A grant for every tx ring slot */
|
|
if (gnttab_alloc_grant_references(TX_MAX_TARGET,
|
|
&np->gref_tx_head) < 0) {
|
|
printk(KERN_ALERT "#### netfront can't alloc tx grant refs\n");
|
|
err = -ENOMEM;
|
|
goto exit;
|
|
}
|
|
/* A grant for every rx ring slot */
|
|
if (gnttab_alloc_grant_references(RX_MAX_TARGET,
|
|
&np->gref_rx_head) < 0) {
|
|
printk(KERN_ALERT "#### netfront can't alloc rx grant refs\n");
|
|
err = -ENOMEM;
|
|
goto exit_free_tx;
|
|
}
|
|
|
|
netdev->open = xennet_open;
|
|
netdev->hard_start_xmit = xennet_start_xmit;
|
|
netdev->stop = xennet_close;
|
|
netif_napi_add(netdev, &np->napi, xennet_poll, 64);
|
|
netdev->uninit = xennet_uninit;
|
|
netdev->change_mtu = xennet_change_mtu;
|
|
netdev->features = NETIF_F_IP_CSUM;
|
|
|
|
SET_ETHTOOL_OPS(netdev, &xennet_ethtool_ops);
|
|
SET_NETDEV_DEV(netdev, &dev->dev);
|
|
|
|
np->netdev = netdev;
|
|
|
|
netif_carrier_off(netdev);
|
|
|
|
return netdev;
|
|
|
|
exit_free_tx:
|
|
gnttab_free_grant_references(np->gref_tx_head);
|
|
exit:
|
|
free_netdev(netdev);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
/**
|
|
* Entry point to this code when a new device is created. Allocate the basic
|
|
* structures and the ring buffers for communication with the backend, and
|
|
* inform the backend of the appropriate details for those.
|
|
*/
|
|
static int __devinit netfront_probe(struct xenbus_device *dev,
|
|
const struct xenbus_device_id *id)
|
|
{
|
|
int err;
|
|
struct net_device *netdev;
|
|
struct netfront_info *info;
|
|
|
|
netdev = xennet_create_dev(dev);
|
|
if (IS_ERR(netdev)) {
|
|
err = PTR_ERR(netdev);
|
|
xenbus_dev_fatal(dev, err, "creating netdev");
|
|
return err;
|
|
}
|
|
|
|
info = netdev_priv(netdev);
|
|
dev->dev.driver_data = info;
|
|
|
|
err = register_netdev(info->netdev);
|
|
if (err) {
|
|
printk(KERN_WARNING "%s: register_netdev err=%d\n",
|
|
__func__, err);
|
|
goto fail;
|
|
}
|
|
|
|
err = xennet_sysfs_addif(info->netdev);
|
|
if (err) {
|
|
unregister_netdev(info->netdev);
|
|
printk(KERN_WARNING "%s: add sysfs failed err=%d\n",
|
|
__func__, err);
|
|
goto fail;
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
free_netdev(netdev);
|
|
dev->dev.driver_data = NULL;
|
|
return err;
|
|
}
|
|
|
|
static void xennet_end_access(int ref, void *page)
|
|
{
|
|
/* This frees the page as a side-effect */
|
|
if (ref != GRANT_INVALID_REF)
|
|
gnttab_end_foreign_access(ref, 0, (unsigned long)page);
|
|
}
|
|
|
|
static void xennet_disconnect_backend(struct netfront_info *info)
|
|
{
|
|
/* Stop old i/f to prevent errors whilst we rebuild the state. */
|
|
spin_lock_bh(&info->rx_lock);
|
|
spin_lock_irq(&info->tx_lock);
|
|
netif_carrier_off(info->netdev);
|
|
spin_unlock_irq(&info->tx_lock);
|
|
spin_unlock_bh(&info->rx_lock);
|
|
|
|
if (info->netdev->irq)
|
|
unbind_from_irqhandler(info->netdev->irq, info->netdev);
|
|
info->evtchn = info->netdev->irq = 0;
|
|
|
|
/* End access and free the pages */
|
|
xennet_end_access(info->tx_ring_ref, info->tx.sring);
|
|
xennet_end_access(info->rx_ring_ref, info->rx.sring);
|
|
|
|
info->tx_ring_ref = GRANT_INVALID_REF;
|
|
info->rx_ring_ref = GRANT_INVALID_REF;
|
|
info->tx.sring = NULL;
|
|
info->rx.sring = NULL;
|
|
}
|
|
|
|
/**
|
|
* We are reconnecting to the backend, due to a suspend/resume, or a backend
|
|
* driver restart. We tear down our netif structure and recreate it, but
|
|
* leave the device-layer structures intact so that this is transparent to the
|
|
* rest of the kernel.
|
|
*/
|
|
static int netfront_resume(struct xenbus_device *dev)
|
|
{
|
|
struct netfront_info *info = dev->dev.driver_data;
|
|
|
|
dev_dbg(&dev->dev, "%s\n", dev->nodename);
|
|
|
|
xennet_disconnect_backend(info);
|
|
return 0;
|
|
}
|
|
|
|
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 irqreturn_t xennet_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct net_device *dev = dev_id;
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&np->tx_lock, flags);
|
|
|
|
if (likely(netif_carrier_ok(dev))) {
|
|
xennet_tx_buf_gc(dev);
|
|
/* Under tx_lock: protects access to rx shared-ring indexes. */
|
|
if (RING_HAS_UNCONSUMED_RESPONSES(&np->rx))
|
|
netif_rx_schedule(dev, &np->napi);
|
|
}
|
|
|
|
spin_unlock_irqrestore(&np->tx_lock, flags);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info)
|
|
{
|
|
struct xen_netif_tx_sring *txs;
|
|
struct xen_netif_rx_sring *rxs;
|
|
int err;
|
|
struct net_device *netdev = info->netdev;
|
|
|
|
info->tx_ring_ref = GRANT_INVALID_REF;
|
|
info->rx_ring_ref = GRANT_INVALID_REF;
|
|
info->rx.sring = NULL;
|
|
info->tx.sring = NULL;
|
|
netdev->irq = 0;
|
|
|
|
err = xen_net_read_mac(dev, netdev->dev_addr);
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
|
|
goto fail;
|
|
}
|
|
|
|
txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_KERNEL);
|
|
if (!txs) {
|
|
err = -ENOMEM;
|
|
xenbus_dev_fatal(dev, err, "allocating tx ring page");
|
|
goto fail;
|
|
}
|
|
SHARED_RING_INIT(txs);
|
|
FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE);
|
|
|
|
err = xenbus_grant_ring(dev, virt_to_mfn(txs));
|
|
if (err < 0) {
|
|
free_page((unsigned long)txs);
|
|
goto fail;
|
|
}
|
|
|
|
info->tx_ring_ref = err;
|
|
rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_KERNEL);
|
|
if (!rxs) {
|
|
err = -ENOMEM;
|
|
xenbus_dev_fatal(dev, err, "allocating rx ring page");
|
|
goto fail;
|
|
}
|
|
SHARED_RING_INIT(rxs);
|
|
FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE);
|
|
|
|
err = xenbus_grant_ring(dev, virt_to_mfn(rxs));
|
|
if (err < 0) {
|
|
free_page((unsigned long)rxs);
|
|
goto fail;
|
|
}
|
|
info->rx_ring_ref = err;
|
|
|
|
err = xenbus_alloc_evtchn(dev, &info->evtchn);
|
|
if (err)
|
|
goto fail;
|
|
|
|
err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt,
|
|
IRQF_SAMPLE_RANDOM, netdev->name,
|
|
netdev);
|
|
if (err < 0)
|
|
goto fail;
|
|
netdev->irq = err;
|
|
return 0;
|
|
|
|
fail:
|
|
return err;
|
|
}
|
|
|
|
/* Common code used when first setting up, and when resuming. */
|
|
static int talk_to_backend(struct xenbus_device *dev,
|
|
struct netfront_info *info)
|
|
{
|
|
const char *message;
|
|
struct xenbus_transaction xbt;
|
|
int err;
|
|
|
|
/* Create shared ring, alloc event channel. */
|
|
err = setup_netfront(dev, info);
|
|
if (err)
|
|
goto out;
|
|
|
|
again:
|
|
err = xenbus_transaction_start(&xbt);
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "starting transaction");
|
|
goto destroy_ring;
|
|
}
|
|
|
|
err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u",
|
|
info->tx_ring_ref);
|
|
if (err) {
|
|
message = "writing tx ring-ref";
|
|
goto abort_transaction;
|
|
}
|
|
err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u",
|
|
info->rx_ring_ref);
|
|
if (err) {
|
|
message = "writing rx ring-ref";
|
|
goto abort_transaction;
|
|
}
|
|
err = xenbus_printf(xbt, dev->nodename,
|
|
"event-channel", "%u", info->evtchn);
|
|
if (err) {
|
|
message = "writing event-channel";
|
|
goto abort_transaction;
|
|
}
|
|
|
|
err = xenbus_printf(xbt, dev->nodename, "request-rx-copy", "%u",
|
|
1);
|
|
if (err) {
|
|
message = "writing request-rx-copy";
|
|
goto abort_transaction;
|
|
}
|
|
|
|
err = xenbus_printf(xbt, dev->nodename, "feature-rx-notify", "%d", 1);
|
|
if (err) {
|
|
message = "writing feature-rx-notify";
|
|
goto abort_transaction;
|
|
}
|
|
|
|
err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", 1);
|
|
if (err) {
|
|
message = "writing feature-sg";
|
|
goto abort_transaction;
|
|
}
|
|
|
|
err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4", "%d", 1);
|
|
if (err) {
|
|
message = "writing feature-gso-tcpv4";
|
|
goto abort_transaction;
|
|
}
|
|
|
|
err = xenbus_transaction_end(xbt, 0);
|
|
if (err) {
|
|
if (err == -EAGAIN)
|
|
goto again;
|
|
xenbus_dev_fatal(dev, err, "completing transaction");
|
|
goto destroy_ring;
|
|
}
|
|
|
|
return 0;
|
|
|
|
abort_transaction:
|
|
xenbus_transaction_end(xbt, 1);
|
|
xenbus_dev_fatal(dev, err, "%s", message);
|
|
destroy_ring:
|
|
xennet_disconnect_backend(info);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static int xennet_set_sg(struct net_device *dev, u32 data)
|
|
{
|
|
if (data) {
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
int val;
|
|
|
|
if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, "feature-sg",
|
|
"%d", &val) < 0)
|
|
val = 0;
|
|
if (!val)
|
|
return -ENOSYS;
|
|
} else if (dev->mtu > ETH_DATA_LEN)
|
|
dev->mtu = ETH_DATA_LEN;
|
|
|
|
return ethtool_op_set_sg(dev, data);
|
|
}
|
|
|
|
static int xennet_set_tso(struct net_device *dev, u32 data)
|
|
{
|
|
if (data) {
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
int val;
|
|
|
|
if (xenbus_scanf(XBT_NIL, np->xbdev->otherend,
|
|
"feature-gso-tcpv4", "%d", &val) < 0)
|
|
val = 0;
|
|
if (!val)
|
|
return -ENOSYS;
|
|
}
|
|
|
|
return ethtool_op_set_tso(dev, data);
|
|
}
|
|
|
|
static void xennet_set_features(struct net_device *dev)
|
|
{
|
|
/* Turn off all GSO bits except ROBUST. */
|
|
dev->features &= (1 << NETIF_F_GSO_SHIFT) - 1;
|
|
dev->features |= NETIF_F_GSO_ROBUST;
|
|
xennet_set_sg(dev, 0);
|
|
|
|
/* We need checksum offload to enable scatter/gather and TSO. */
|
|
if (!(dev->features & NETIF_F_IP_CSUM))
|
|
return;
|
|
|
|
if (!xennet_set_sg(dev, 1))
|
|
xennet_set_tso(dev, 1);
|
|
}
|
|
|
|
static int xennet_connect(struct net_device *dev)
|
|
{
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
int i, requeue_idx, err;
|
|
struct sk_buff *skb;
|
|
grant_ref_t ref;
|
|
struct xen_netif_rx_request *req;
|
|
unsigned int feature_rx_copy;
|
|
|
|
err = xenbus_scanf(XBT_NIL, np->xbdev->otherend,
|
|
"feature-rx-copy", "%u", &feature_rx_copy);
|
|
if (err != 1)
|
|
feature_rx_copy = 0;
|
|
|
|
if (!feature_rx_copy) {
|
|
dev_info(&dev->dev,
|
|
"backend does not support copying recieve path");
|
|
return -ENODEV;
|
|
}
|
|
|
|
err = talk_to_backend(np->xbdev, np);
|
|
if (err)
|
|
return err;
|
|
|
|
xennet_set_features(dev);
|
|
|
|
spin_lock_bh(&np->rx_lock);
|
|
spin_lock_irq(&np->tx_lock);
|
|
|
|
/* Step 1: Discard all pending TX packet fragments. */
|
|
xennet_release_tx_bufs(np);
|
|
|
|
/* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */
|
|
for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) {
|
|
if (!np->rx_skbs[i])
|
|
continue;
|
|
|
|
skb = np->rx_skbs[requeue_idx] = xennet_get_rx_skb(np, i);
|
|
ref = np->grant_rx_ref[requeue_idx] = xennet_get_rx_ref(np, i);
|
|
req = RING_GET_REQUEST(&np->rx, requeue_idx);
|
|
|
|
gnttab_grant_foreign_access_ref(
|
|
ref, np->xbdev->otherend_id,
|
|
pfn_to_mfn(page_to_pfn(skb_shinfo(skb)->
|
|
frags->page)),
|
|
0);
|
|
req->gref = ref;
|
|
req->id = requeue_idx;
|
|
|
|
requeue_idx++;
|
|
}
|
|
|
|
np->rx.req_prod_pvt = requeue_idx;
|
|
|
|
/*
|
|
* Step 3: All public and private state should now be sane. Get
|
|
* ready to start sending and receiving packets and give the driver
|
|
* domain a kick because we've probably just requeued some
|
|
* packets.
|
|
*/
|
|
netif_carrier_on(np->netdev);
|
|
notify_remote_via_irq(np->netdev->irq);
|
|
xennet_tx_buf_gc(dev);
|
|
xennet_alloc_rx_buffers(dev);
|
|
|
|
spin_unlock_irq(&np->tx_lock);
|
|
spin_unlock_bh(&np->rx_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Callback received when the backend's state changes.
|
|
*/
|
|
static void backend_changed(struct xenbus_device *dev,
|
|
enum xenbus_state backend_state)
|
|
{
|
|
struct netfront_info *np = dev->dev.driver_data;
|
|
struct net_device *netdev = np->netdev;
|
|
|
|
dev_dbg(&dev->dev, "%s\n", xenbus_strstate(backend_state));
|
|
|
|
switch (backend_state) {
|
|
case XenbusStateInitialising:
|
|
case XenbusStateInitialised:
|
|
case XenbusStateConnected:
|
|
case XenbusStateUnknown:
|
|
case XenbusStateClosed:
|
|
break;
|
|
|
|
case XenbusStateInitWait:
|
|
if (dev->state != XenbusStateInitialising)
|
|
break;
|
|
if (xennet_connect(netdev) != 0)
|
|
break;
|
|
xenbus_switch_state(dev, XenbusStateConnected);
|
|
break;
|
|
|
|
case XenbusStateClosing:
|
|
xenbus_frontend_closed(dev);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static struct ethtool_ops xennet_ethtool_ops =
|
|
{
|
|
.set_tx_csum = ethtool_op_set_tx_csum,
|
|
.set_sg = xennet_set_sg,
|
|
.set_tso = xennet_set_tso,
|
|
.get_link = ethtool_op_get_link,
|
|
};
|
|
|
|
#ifdef CONFIG_SYSFS
|
|
static ssize_t show_rxbuf_min(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct net_device *netdev = to_net_dev(dev);
|
|
struct netfront_info *info = netdev_priv(netdev);
|
|
|
|
return sprintf(buf, "%u\n", info->rx_min_target);
|
|
}
|
|
|
|
static ssize_t store_rxbuf_min(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t len)
|
|
{
|
|
struct net_device *netdev = to_net_dev(dev);
|
|
struct netfront_info *np = netdev_priv(netdev);
|
|
char *endp;
|
|
unsigned long target;
|
|
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
target = simple_strtoul(buf, &endp, 0);
|
|
if (endp == buf)
|
|
return -EBADMSG;
|
|
|
|
if (target < RX_MIN_TARGET)
|
|
target = RX_MIN_TARGET;
|
|
if (target > RX_MAX_TARGET)
|
|
target = RX_MAX_TARGET;
|
|
|
|
spin_lock_bh(&np->rx_lock);
|
|
if (target > np->rx_max_target)
|
|
np->rx_max_target = target;
|
|
np->rx_min_target = target;
|
|
if (target > np->rx_target)
|
|
np->rx_target = target;
|
|
|
|
xennet_alloc_rx_buffers(netdev);
|
|
|
|
spin_unlock_bh(&np->rx_lock);
|
|
return len;
|
|
}
|
|
|
|
static ssize_t show_rxbuf_max(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct net_device *netdev = to_net_dev(dev);
|
|
struct netfront_info *info = netdev_priv(netdev);
|
|
|
|
return sprintf(buf, "%u\n", info->rx_max_target);
|
|
}
|
|
|
|
static ssize_t store_rxbuf_max(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t len)
|
|
{
|
|
struct net_device *netdev = to_net_dev(dev);
|
|
struct netfront_info *np = netdev_priv(netdev);
|
|
char *endp;
|
|
unsigned long target;
|
|
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
target = simple_strtoul(buf, &endp, 0);
|
|
if (endp == buf)
|
|
return -EBADMSG;
|
|
|
|
if (target < RX_MIN_TARGET)
|
|
target = RX_MIN_TARGET;
|
|
if (target > RX_MAX_TARGET)
|
|
target = RX_MAX_TARGET;
|
|
|
|
spin_lock_bh(&np->rx_lock);
|
|
if (target < np->rx_min_target)
|
|
np->rx_min_target = target;
|
|
np->rx_max_target = target;
|
|
if (target < np->rx_target)
|
|
np->rx_target = target;
|
|
|
|
xennet_alloc_rx_buffers(netdev);
|
|
|
|
spin_unlock_bh(&np->rx_lock);
|
|
return len;
|
|
}
|
|
|
|
static ssize_t show_rxbuf_cur(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct net_device *netdev = to_net_dev(dev);
|
|
struct netfront_info *info = netdev_priv(netdev);
|
|
|
|
return sprintf(buf, "%u\n", info->rx_target);
|
|
}
|
|
|
|
static struct device_attribute xennet_attrs[] = {
|
|
__ATTR(rxbuf_min, S_IRUGO|S_IWUSR, show_rxbuf_min, store_rxbuf_min),
|
|
__ATTR(rxbuf_max, S_IRUGO|S_IWUSR, show_rxbuf_max, store_rxbuf_max),
|
|
__ATTR(rxbuf_cur, S_IRUGO, show_rxbuf_cur, NULL),
|
|
};
|
|
|
|
static int xennet_sysfs_addif(struct net_device *netdev)
|
|
{
|
|
int i;
|
|
int err;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(xennet_attrs); i++) {
|
|
err = device_create_file(&netdev->dev,
|
|
&xennet_attrs[i]);
|
|
if (err)
|
|
goto fail;
|
|
}
|
|
return 0;
|
|
|
|
fail:
|
|
while (--i >= 0)
|
|
device_remove_file(&netdev->dev, &xennet_attrs[i]);
|
|
return err;
|
|
}
|
|
|
|
static void xennet_sysfs_delif(struct net_device *netdev)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(xennet_attrs); i++)
|
|
device_remove_file(&netdev->dev, &xennet_attrs[i]);
|
|
}
|
|
|
|
#endif /* CONFIG_SYSFS */
|
|
|
|
static struct xenbus_device_id netfront_ids[] = {
|
|
{ "vif" },
|
|
{ "" }
|
|
};
|
|
|
|
|
|
static int __devexit xennet_remove(struct xenbus_device *dev)
|
|
{
|
|
struct netfront_info *info = dev->dev.driver_data;
|
|
|
|
dev_dbg(&dev->dev, "%s\n", dev->nodename);
|
|
|
|
unregister_netdev(info->netdev);
|
|
|
|
xennet_disconnect_backend(info);
|
|
|
|
del_timer_sync(&info->rx_refill_timer);
|
|
|
|
xennet_sysfs_delif(info->netdev);
|
|
|
|
free_netdev(info->netdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct xenbus_driver netfront = {
|
|
.name = "vif",
|
|
.owner = THIS_MODULE,
|
|
.ids = netfront_ids,
|
|
.probe = netfront_probe,
|
|
.remove = __devexit_p(xennet_remove),
|
|
.resume = netfront_resume,
|
|
.otherend_changed = backend_changed,
|
|
};
|
|
|
|
static int __init netif_init(void)
|
|
{
|
|
if (!is_running_on_xen())
|
|
return -ENODEV;
|
|
|
|
if (is_initial_xendomain())
|
|
return 0;
|
|
|
|
printk(KERN_INFO "Initialising Xen virtual ethernet driver.\n");
|
|
|
|
return xenbus_register_frontend(&netfront);
|
|
}
|
|
module_init(netif_init);
|
|
|
|
|
|
static void __exit netif_exit(void)
|
|
{
|
|
if (is_initial_xendomain())
|
|
return;
|
|
|
|
return xenbus_unregister_driver(&netfront);
|
|
}
|
|
module_exit(netif_exit);
|
|
|
|
MODULE_DESCRIPTION("Xen virtual network device frontend");
|
|
MODULE_LICENSE("GPL");
|