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![Zoltan Kiss](/assets/img/avatar_default.png)
There is a long known problem with the netfront/netback interface: if the guest tries to send a packet which constitues more than MAX_SKB_FRAGS + 1 ring slots, it gets dropped. The reason is that netback maps these slots to a frag in the frags array, which is limited by size. Having so many slots can occur since compound pages were introduced, as the ring protocol slice them up into individual (non-compound) page aligned slots. The theoretical worst case scenario looks like this (note, skbs are limited to 64 Kb here): linear buffer: at most PAGE_SIZE - 17 * 2 bytes, overlapping page boundary, using 2 slots first 15 frags: 1 + PAGE_SIZE + 1 bytes long, first and last bytes are at the end and the beginning of a page, therefore they use 3 * 15 = 45 slots last 2 frags: 1 + 1 bytes, overlapping page boundary, 2 * 2 = 4 slots Although I don't think this 51 slots skb can really happen, we need a solution which can deal with every scenario. In real life there is only a few slots overdue, but usually it causes the TCP stream to be blocked, as the retry will most likely have the same buffer layout. This patch solves this problem by linearizing the packet. This is not the fastest way, and it can fail much easier as it tries to allocate a big linear area for the whole packet, but probably easier by an order of magnitude than anything else. Probably this code path is not touched very frequently anyway. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Paul Durrant <paul.durrant@citrix.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2375 lines
59 KiB
C
2375 lines
59 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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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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 <net/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 <linux/slab.h>
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#include <net/ip.h>
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#include <asm/xen/page.h>
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#include <xen/xen.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/platform_pci.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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/* Module parameters */
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static unsigned int xennet_max_queues;
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module_param_named(max_queues, xennet_max_queues, uint, 0644);
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MODULE_PARM_DESC(max_queues,
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"Maximum number of queues per virtual interface");
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static const struct ethtool_ops xennet_ethtool_ops;
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struct netfront_cb {
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int pull_to;
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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 __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE)
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#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE)
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#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256)
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/* Queue name is interface name with "-qNNN" appended */
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#define QUEUE_NAME_SIZE (IFNAMSIZ + 6)
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/* IRQ name is queue name with "-tx" or "-rx" appended */
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#define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3)
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struct netfront_stats {
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u64 rx_packets;
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u64 tx_packets;
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u64 rx_bytes;
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u64 tx_bytes;
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struct u64_stats_sync syncp;
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};
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struct netfront_info;
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struct netfront_queue {
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unsigned int id; /* Queue ID, 0-based */
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char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */
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struct netfront_info *info;
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struct napi_struct napi;
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/* Split event channels support, tx_* == rx_* when using
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* single event channel.
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*/
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unsigned int tx_evtchn, rx_evtchn;
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unsigned int tx_irq, rx_irq;
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/* Only used when split event channels support is enabled */
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char tx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-tx */
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char rx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */
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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 long 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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struct page *grant_tx_page[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_info {
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struct list_head list;
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struct net_device *netdev;
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struct xenbus_device *xbdev;
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/* Multi-queue support */
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struct netfront_queue *queues;
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/* Statistics */
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struct netfront_stats __percpu *stats;
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atomic_t rx_gso_checksum_fixup;
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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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static void skb_entry_set_link(union skb_entry *list, unsigned short id)
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{
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list->link = id;
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}
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static int skb_entry_is_link(const union skb_entry *list)
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{
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BUILD_BUG_ON(sizeof(list->skb) != sizeof(list->link));
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return (unsigned long)list->skb < PAGE_OFFSET;
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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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skb_entry_set_link(&list[id], *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_queue *queue,
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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 = queue->rx_skbs[i];
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queue->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_queue *queue,
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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 = queue->grant_rx_ref[i];
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queue->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 bool 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 netfront_queue *queue = (struct netfront_queue *)data;
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napi_schedule(&queue->napi);
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}
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static int netfront_tx_slot_available(struct netfront_queue *queue)
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{
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return (queue->tx.req_prod_pvt - queue->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 netfront_queue *queue)
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{
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struct net_device *dev = queue->info->netdev;
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struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, queue->id);
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if (unlikely(netif_tx_queue_stopped(dev_queue)) &&
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netfront_tx_slot_available(queue) &&
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likely(netif_running(dev)))
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netif_tx_wake_queue(netdev_get_tx_queue(dev, queue->id));
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}
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static void xennet_alloc_rx_buffers(struct netfront_queue *queue)
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{
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unsigned short id;
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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 = queue->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(queue->info->netdev)))
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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 = queue->rx_target - (req_prod - queue->rx.rsp_cons);
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for (i = skb_queue_len(&queue->rx_batch); i < batch_target; i++) {
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skb = __netdev_alloc_skb(queue->info->netdev,
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RX_COPY_THRESHOLD + NET_IP_ALIGN,
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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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/* Align ip header to a 16 bytes boundary */
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skb_reserve(skb, NET_IP_ALIGN);
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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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/* Could not allocate any skbuffs. Try again later. */
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mod_timer(&queue->rx_refill_timer,
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jiffies + (HZ/10));
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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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break;
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}
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skb_add_rx_frag(skb, 0, page, 0, 0, PAGE_SIZE);
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__skb_queue_tail(&queue->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 < (queue->rx_target/2)) {
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if (req_prod > queue->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 - queue->rx.sring->rsp_prod) < (queue->rx_target / 4)) &&
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((queue->rx_target *= 2) > queue->rx_max_target))
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queue->rx_target = queue->rx_max_target;
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refill:
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for (i = 0; ; i++) {
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skb = __skb_dequeue(&queue->rx_batch);
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if (skb == NULL)
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break;
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skb->dev = queue->info->netdev;
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id = xennet_rxidx(req_prod + i);
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BUG_ON(queue->rx_skbs[id]);
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queue->rx_skbs[id] = skb;
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ref = gnttab_claim_grant_reference(&queue->gref_rx_head);
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BUG_ON((signed short)ref < 0);
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queue->grant_rx_ref[id] = ref;
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pfn = page_to_pfn(skb_frag_page(&skb_shinfo(skb)->frags[0]));
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vaddr = page_address(skb_frag_page(&skb_shinfo(skb)->frags[0]));
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req = RING_GET_REQUEST(&queue->rx, req_prod + i);
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gnttab_grant_foreign_access_ref(ref,
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queue->info->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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queue->rx.req_prod_pvt = req_prod + i;
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push:
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RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->rx, notify);
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if (notify)
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notify_remote_via_irq(queue->rx_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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unsigned int num_queues = dev->real_num_tx_queues;
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unsigned int i = 0;
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struct netfront_queue *queue = NULL;
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for (i = 0; i < num_queues; ++i) {
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queue = &np->queues[i];
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napi_enable(&queue->napi);
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spin_lock_bh(&queue->rx_lock);
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if (netif_carrier_ok(dev)) {
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xennet_alloc_rx_buffers(queue);
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queue->rx.sring->rsp_event = queue->rx.rsp_cons + 1;
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if (RING_HAS_UNCONSUMED_RESPONSES(&queue->rx))
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napi_schedule(&queue->napi);
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}
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spin_unlock_bh(&queue->rx_lock);
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}
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netif_tx_start_all_queues(dev);
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return 0;
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}
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static void xennet_tx_buf_gc(struct netfront_queue *queue)
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{
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RING_IDX cons, prod;
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unsigned short id;
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struct sk_buff *skb;
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|
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BUG_ON(!netif_carrier_ok(queue->info->netdev));
|
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do {
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prod = queue->tx.sring->rsp_prod;
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rmb(); /* Ensure we see responses up to 'rp'. */
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|
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for (cons = queue->tx.rsp_cons; cons != prod; cons++) {
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struct xen_netif_tx_response *txrsp;
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|
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txrsp = RING_GET_RESPONSE(&queue->tx, cons);
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if (txrsp->status == XEN_NETIF_RSP_NULL)
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continue;
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|
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id = txrsp->id;
|
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skb = queue->tx_skbs[id].skb;
|
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if (unlikely(gnttab_query_foreign_access(
|
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queue->grant_tx_ref[id]) != 0)) {
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pr_alert("%s: warning -- grant still in use by backend domain\n",
|
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__func__);
|
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BUG();
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}
|
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gnttab_end_foreign_access_ref(
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queue->grant_tx_ref[id], GNTMAP_readonly);
|
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gnttab_release_grant_reference(
|
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&queue->gref_tx_head, queue->grant_tx_ref[id]);
|
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queue->grant_tx_ref[id] = GRANT_INVALID_REF;
|
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queue->grant_tx_page[id] = NULL;
|
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add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, id);
|
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dev_kfree_skb_irq(skb);
|
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}
|
|
|
|
queue->tx.rsp_cons = prod;
|
|
|
|
/*
|
|
* Set a new event, then check for race with update of tx_cons.
|
|
* Note that it is essential to schedule a callback, no matter
|
|
* 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
|
|
* data is outstanding: in such cases notification from Xen is
|
|
* likely to be the only kick that we'll get.
|
|
*/
|
|
queue->tx.sring->rsp_event =
|
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prod + ((queue->tx.sring->req_prod - prod) >> 1) + 1;
|
|
mb(); /* update shared area */
|
|
} while ((cons == prod) && (prod != queue->tx.sring->rsp_prod));
|
|
|
|
xennet_maybe_wake_tx(queue);
|
|
}
|
|
|
|
static void xennet_make_frags(struct sk_buff *skb, struct netfront_queue *queue,
|
|
struct xen_netif_tx_request *tx)
|
|
{
|
|
char *data = skb->data;
|
|
unsigned long mfn;
|
|
RING_IDX prod = queue->tx.req_prod_pvt;
|
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int frags = skb_shinfo(skb)->nr_frags;
|
|
unsigned int offset = offset_in_page(data);
|
|
unsigned int len = skb_headlen(skb);
|
|
unsigned int id;
|
|
grant_ref_t ref;
|
|
int i;
|
|
|
|
/* While the header overlaps a page boundary (including being
|
|
larger than a page), split it it into page-sized chunks. */
|
|
while (len > PAGE_SIZE - offset) {
|
|
tx->size = PAGE_SIZE - offset;
|
|
tx->flags |= XEN_NETTXF_more_data;
|
|
len -= tx->size;
|
|
data += tx->size;
|
|
offset = 0;
|
|
|
|
id = get_id_from_freelist(&queue->tx_skb_freelist, queue->tx_skbs);
|
|
queue->tx_skbs[id].skb = skb_get(skb);
|
|
tx = RING_GET_REQUEST(&queue->tx, prod++);
|
|
tx->id = id;
|
|
ref = gnttab_claim_grant_reference(&queue->gref_tx_head);
|
|
BUG_ON((signed short)ref < 0);
|
|
|
|
mfn = virt_to_mfn(data);
|
|
gnttab_grant_foreign_access_ref(ref, queue->info->xbdev->otherend_id,
|
|
mfn, GNTMAP_readonly);
|
|
|
|
queue->grant_tx_page[id] = virt_to_page(data);
|
|
tx->gref = queue->grant_tx_ref[id] = ref;
|
|
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;
|
|
struct page *page = skb_frag_page(frag);
|
|
|
|
len = skb_frag_size(frag);
|
|
offset = frag->page_offset;
|
|
|
|
/* Data must not cross a page boundary. */
|
|
BUG_ON(len + offset > PAGE_SIZE<<compound_order(page));
|
|
|
|
/* Skip unused frames from start of page */
|
|
page += offset >> PAGE_SHIFT;
|
|
offset &= ~PAGE_MASK;
|
|
|
|
while (len > 0) {
|
|
unsigned long bytes;
|
|
|
|
BUG_ON(offset >= PAGE_SIZE);
|
|
|
|
bytes = PAGE_SIZE - offset;
|
|
if (bytes > len)
|
|
bytes = len;
|
|
|
|
tx->flags |= XEN_NETTXF_more_data;
|
|
|
|
id = get_id_from_freelist(&queue->tx_skb_freelist,
|
|
queue->tx_skbs);
|
|
queue->tx_skbs[id].skb = skb_get(skb);
|
|
tx = RING_GET_REQUEST(&queue->tx, prod++);
|
|
tx->id = id;
|
|
ref = gnttab_claim_grant_reference(&queue->gref_tx_head);
|
|
BUG_ON((signed short)ref < 0);
|
|
|
|
mfn = pfn_to_mfn(page_to_pfn(page));
|
|
gnttab_grant_foreign_access_ref(ref,
|
|
queue->info->xbdev->otherend_id,
|
|
mfn, GNTMAP_readonly);
|
|
|
|
queue->grant_tx_page[id] = page;
|
|
tx->gref = queue->grant_tx_ref[id] = ref;
|
|
tx->offset = offset;
|
|
tx->size = bytes;
|
|
tx->flags = 0;
|
|
|
|
offset += bytes;
|
|
len -= bytes;
|
|
|
|
/* Next frame */
|
|
if (offset == PAGE_SIZE && len) {
|
|
BUG_ON(!PageCompound(page));
|
|
page++;
|
|
offset = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
queue->tx.req_prod_pvt = prod;
|
|
}
|
|
|
|
/*
|
|
* Count how many ring slots are required to send the frags of this
|
|
* skb. Each frag might be a compound page.
|
|
*/
|
|
static int xennet_count_skb_frag_slots(struct sk_buff *skb)
|
|
{
|
|
int i, frags = skb_shinfo(skb)->nr_frags;
|
|
int pages = 0;
|
|
|
|
for (i = 0; i < frags; i++) {
|
|
skb_frag_t *frag = skb_shinfo(skb)->frags + i;
|
|
unsigned long size = skb_frag_size(frag);
|
|
unsigned long offset = frag->page_offset;
|
|
|
|
/* Skip unused frames from start of page */
|
|
offset &= ~PAGE_MASK;
|
|
|
|
pages += PFN_UP(offset + size);
|
|
}
|
|
|
|
return pages;
|
|
}
|
|
|
|
static u16 xennet_select_queue(struct net_device *dev, struct sk_buff *skb,
|
|
void *accel_priv, select_queue_fallback_t fallback)
|
|
{
|
|
unsigned int num_queues = dev->real_num_tx_queues;
|
|
u32 hash;
|
|
u16 queue_idx;
|
|
|
|
/* First, check if there is only one queue */
|
|
if (num_queues == 1) {
|
|
queue_idx = 0;
|
|
} else {
|
|
hash = skb_get_hash(skb);
|
|
queue_idx = hash % num_queues;
|
|
}
|
|
|
|
return queue_idx;
|
|
}
|
|
|
|
static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
unsigned short id;
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
struct netfront_stats *stats = this_cpu_ptr(np->stats);
|
|
struct xen_netif_tx_request *tx;
|
|
char *data = skb->data;
|
|
RING_IDX i;
|
|
grant_ref_t ref;
|
|
unsigned long mfn;
|
|
int notify;
|
|
int slots;
|
|
unsigned int offset = offset_in_page(data);
|
|
unsigned int len = skb_headlen(skb);
|
|
unsigned long flags;
|
|
struct netfront_queue *queue = NULL;
|
|
unsigned int num_queues = dev->real_num_tx_queues;
|
|
u16 queue_index;
|
|
|
|
/* Drop the packet if no queues are set up */
|
|
if (num_queues < 1)
|
|
goto drop;
|
|
/* Determine which queue to transmit this SKB on */
|
|
queue_index = skb_get_queue_mapping(skb);
|
|
queue = &np->queues[queue_index];
|
|
|
|
/* If skb->len is too big for wire format, drop skb and alert
|
|
* user about misconfiguration.
|
|
*/
|
|
if (unlikely(skb->len > XEN_NETIF_MAX_TX_SIZE)) {
|
|
net_alert_ratelimited(
|
|
"xennet: skb->len = %u, too big for wire format\n",
|
|
skb->len);
|
|
goto drop;
|
|
}
|
|
|
|
slots = DIV_ROUND_UP(offset + len, PAGE_SIZE) +
|
|
xennet_count_skb_frag_slots(skb);
|
|
if (unlikely(slots > MAX_SKB_FRAGS + 1)) {
|
|
net_dbg_ratelimited("xennet: skb rides the rocket: %d slots, %d bytes\n",
|
|
slots, skb->len);
|
|
if (skb_linearize(skb))
|
|
goto drop;
|
|
}
|
|
|
|
spin_lock_irqsave(&queue->tx_lock, flags);
|
|
|
|
if (unlikely(!netif_carrier_ok(dev) ||
|
|
(slots > 1 && !xennet_can_sg(dev)) ||
|
|
netif_needs_gso(skb, netif_skb_features(skb)))) {
|
|
spin_unlock_irqrestore(&queue->tx_lock, flags);
|
|
goto drop;
|
|
}
|
|
|
|
i = queue->tx.req_prod_pvt;
|
|
|
|
id = get_id_from_freelist(&queue->tx_skb_freelist, queue->tx_skbs);
|
|
queue->tx_skbs[id].skb = skb;
|
|
|
|
tx = RING_GET_REQUEST(&queue->tx, i);
|
|
|
|
tx->id = id;
|
|
ref = gnttab_claim_grant_reference(&queue->gref_tx_head);
|
|
BUG_ON((signed short)ref < 0);
|
|
mfn = virt_to_mfn(data);
|
|
gnttab_grant_foreign_access_ref(
|
|
ref, queue->info->xbdev->otherend_id, mfn, GNTMAP_readonly);
|
|
queue->grant_tx_page[id] = virt_to_page(data);
|
|
tx->gref = queue->grant_tx_ref[id] = ref;
|
|
tx->offset = offset;
|
|
tx->size = len;
|
|
|
|
tx->flags = 0;
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL)
|
|
/* local packet? */
|
|
tx->flags |= XEN_NETTXF_csum_blank | XEN_NETTXF_data_validated;
|
|
else if (skb->ip_summed == CHECKSUM_UNNECESSARY)
|
|
/* remote but checksummed. */
|
|
tx->flags |= XEN_NETTXF_data_validated;
|
|
|
|
if (skb_shinfo(skb)->gso_size) {
|
|
struct xen_netif_extra_info *gso;
|
|
|
|
gso = (struct xen_netif_extra_info *)
|
|
RING_GET_REQUEST(&queue->tx, ++i);
|
|
|
|
tx->flags |= XEN_NETTXF_extra_info;
|
|
|
|
gso->u.gso.size = skb_shinfo(skb)->gso_size;
|
|
gso->u.gso.type = (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) ?
|
|
XEN_NETIF_GSO_TYPE_TCPV6 :
|
|
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;
|
|
}
|
|
|
|
queue->tx.req_prod_pvt = i + 1;
|
|
|
|
xennet_make_frags(skb, queue, tx);
|
|
tx->size = skb->len;
|
|
|
|
RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&queue->tx, notify);
|
|
if (notify)
|
|
notify_remote_via_irq(queue->tx_irq);
|
|
|
|
u64_stats_update_begin(&stats->syncp);
|
|
stats->tx_bytes += skb->len;
|
|
stats->tx_packets++;
|
|
u64_stats_update_end(&stats->syncp);
|
|
|
|
/* Note: It is not safe to access skb after xennet_tx_buf_gc()! */
|
|
xennet_tx_buf_gc(queue);
|
|
|
|
if (!netfront_tx_slot_available(queue))
|
|
netif_tx_stop_queue(netdev_get_tx_queue(dev, queue->id));
|
|
|
|
spin_unlock_irqrestore(&queue->tx_lock, flags);
|
|
|
|
return NETDEV_TX_OK;
|
|
|
|
drop:
|
|
dev->stats.tx_dropped++;
|
|
dev_kfree_skb_any(skb);
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
static int xennet_close(struct net_device *dev)
|
|
{
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
unsigned int num_queues = dev->real_num_tx_queues;
|
|
unsigned int i;
|
|
struct netfront_queue *queue;
|
|
netif_tx_stop_all_queues(np->netdev);
|
|
for (i = 0; i < num_queues; ++i) {
|
|
queue = &np->queues[i];
|
|
napi_disable(&queue->napi);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void xennet_move_rx_slot(struct netfront_queue *queue, struct sk_buff *skb,
|
|
grant_ref_t ref)
|
|
{
|
|
int new = xennet_rxidx(queue->rx.req_prod_pvt);
|
|
|
|
BUG_ON(queue->rx_skbs[new]);
|
|
queue->rx_skbs[new] = skb;
|
|
queue->grant_rx_ref[new] = ref;
|
|
RING_GET_REQUEST(&queue->rx, queue->rx.req_prod_pvt)->id = new;
|
|
RING_GET_REQUEST(&queue->rx, queue->rx.req_prod_pvt)->gref = ref;
|
|
queue->rx.req_prod_pvt++;
|
|
}
|
|
|
|
static int xennet_get_extras(struct netfront_queue *queue,
|
|
struct xen_netif_extra_info *extras,
|
|
RING_IDX rp)
|
|
|
|
{
|
|
struct xen_netif_extra_info *extra;
|
|
struct device *dev = &queue->info->netdev->dev;
|
|
RING_IDX cons = queue->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(&queue->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(queue, cons);
|
|
ref = xennet_get_rx_ref(queue, cons);
|
|
xennet_move_rx_slot(queue, skb, ref);
|
|
} while (extra->flags & XEN_NETIF_EXTRA_FLAG_MORE);
|
|
|
|
queue->rx.rsp_cons = cons;
|
|
return err;
|
|
}
|
|
|
|
static int xennet_get_responses(struct netfront_queue *queue,
|
|
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 = &queue->info->netdev->dev;
|
|
RING_IDX cons = queue->rx.rsp_cons;
|
|
struct sk_buff *skb = xennet_get_rx_skb(queue, cons);
|
|
grant_ref_t ref = xennet_get_rx_ref(queue, cons);
|
|
int max = MAX_SKB_FRAGS + (rx->status <= RX_COPY_THRESHOLD);
|
|
int slots = 1;
|
|
int err = 0;
|
|
unsigned long ret;
|
|
|
|
if (rx->flags & XEN_NETRXF_extra_info) {
|
|
err = xennet_get_extras(queue, extras, rp);
|
|
cons = queue->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(queue, 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 backend.
|
|
*/
|
|
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(&queue->gref_rx_head, ref);
|
|
|
|
__skb_queue_tail(list, skb);
|
|
|
|
next:
|
|
if (!(rx->flags & XEN_NETRXF_more_data))
|
|
break;
|
|
|
|
if (cons + slots == rp) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "Need more slots\n");
|
|
err = -ENOENT;
|
|
break;
|
|
}
|
|
|
|
rx = RING_GET_RESPONSE(&queue->rx, cons + slots);
|
|
skb = xennet_get_rx_skb(queue, cons + slots);
|
|
ref = xennet_get_rx_ref(queue, cons + slots);
|
|
slots++;
|
|
}
|
|
|
|
if (unlikely(slots > max)) {
|
|
if (net_ratelimit())
|
|
dev_warn(dev, "Too many slots\n");
|
|
err = -E2BIG;
|
|
}
|
|
|
|
if (unlikely(err))
|
|
queue->rx.rsp_cons = cons + slots;
|
|
|
|
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())
|
|
pr_warn("GSO size must not be zero\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV4 &&
|
|
gso->u.gso.type != XEN_NETIF_GSO_TYPE_TCPV6) {
|
|
if (net_ratelimit())
|
|
pr_warn("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 =
|
|
(gso->u.gso.type == XEN_NETIF_GSO_TYPE_TCPV4) ?
|
|
SKB_GSO_TCPV4 :
|
|
SKB_GSO_TCPV6;
|
|
|
|
/* 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_queue *queue,
|
|
struct sk_buff *skb,
|
|
struct sk_buff_head *list)
|
|
{
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
RING_IDX cons = queue->rx.rsp_cons;
|
|
struct sk_buff *nskb;
|
|
|
|
while ((nskb = __skb_dequeue(list))) {
|
|
struct xen_netif_rx_response *rx =
|
|
RING_GET_RESPONSE(&queue->rx, ++cons);
|
|
skb_frag_t *nfrag = &skb_shinfo(nskb)->frags[0];
|
|
|
|
if (shinfo->nr_frags == MAX_SKB_FRAGS) {
|
|
unsigned int pull_to = NETFRONT_SKB_CB(skb)->pull_to;
|
|
|
|
BUG_ON(pull_to <= skb_headlen(skb));
|
|
__pskb_pull_tail(skb, pull_to - skb_headlen(skb));
|
|
}
|
|
BUG_ON(shinfo->nr_frags >= MAX_SKB_FRAGS);
|
|
|
|
skb_add_rx_frag(skb, shinfo->nr_frags, skb_frag_page(nfrag),
|
|
rx->offset, rx->status, PAGE_SIZE);
|
|
|
|
skb_shinfo(nskb)->nr_frags = 0;
|
|
kfree_skb(nskb);
|
|
}
|
|
|
|
return cons;
|
|
}
|
|
|
|
static int checksum_setup(struct net_device *dev, struct sk_buff *skb)
|
|
{
|
|
bool recalculate_partial_csum = false;
|
|
|
|
/*
|
|
* A GSO SKB must be CHECKSUM_PARTIAL. However some buggy
|
|
* peers can fail to set NETRXF_csum_blank when sending a GSO
|
|
* frame. In this case force the SKB to CHECKSUM_PARTIAL and
|
|
* recalculate the partial checksum.
|
|
*/
|
|
if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) {
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
atomic_inc(&np->rx_gso_checksum_fixup);
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
recalculate_partial_csum = true;
|
|
}
|
|
|
|
/* A non-CHECKSUM_PARTIAL SKB does not require setup. */
|
|
if (skb->ip_summed != CHECKSUM_PARTIAL)
|
|
return 0;
|
|
|
|
return skb_checksum_setup(skb, recalculate_partial_csum);
|
|
}
|
|
|
|
static int handle_incoming_queue(struct netfront_queue *queue,
|
|
struct sk_buff_head *rxq)
|
|
{
|
|
struct netfront_stats *stats = this_cpu_ptr(queue->info->stats);
|
|
int packets_dropped = 0;
|
|
struct sk_buff *skb;
|
|
|
|
while ((skb = __skb_dequeue(rxq)) != NULL) {
|
|
int pull_to = NETFRONT_SKB_CB(skb)->pull_to;
|
|
|
|
if (pull_to > skb_headlen(skb))
|
|
__pskb_pull_tail(skb, pull_to - skb_headlen(skb));
|
|
|
|
/* Ethernet work: Delayed to here as it peeks the header. */
|
|
skb->protocol = eth_type_trans(skb, queue->info->netdev);
|
|
skb_reset_network_header(skb);
|
|
|
|
if (checksum_setup(queue->info->netdev, skb)) {
|
|
kfree_skb(skb);
|
|
packets_dropped++;
|
|
queue->info->netdev->stats.rx_errors++;
|
|
continue;
|
|
}
|
|
|
|
u64_stats_update_begin(&stats->syncp);
|
|
stats->rx_packets++;
|
|
stats->rx_bytes += skb->len;
|
|
u64_stats_update_end(&stats->syncp);
|
|
|
|
/* Pass it up. */
|
|
napi_gro_receive(&queue->napi, skb);
|
|
}
|
|
|
|
return packets_dropped;
|
|
}
|
|
|
|
static int xennet_poll(struct napi_struct *napi, int budget)
|
|
{
|
|
struct netfront_queue *queue = container_of(napi, struct netfront_queue, napi);
|
|
struct net_device *dev = queue->info->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;
|
|
int err;
|
|
|
|
spin_lock(&queue->rx_lock);
|
|
|
|
skb_queue_head_init(&rxq);
|
|
skb_queue_head_init(&errq);
|
|
skb_queue_head_init(&tmpq);
|
|
|
|
rp = queue->rx.sring->rsp_prod;
|
|
rmb(); /* Ensure we see queued responses up to 'rp'. */
|
|
|
|
i = queue->rx.rsp_cons;
|
|
work_done = 0;
|
|
while ((i != rp) && (work_done < budget)) {
|
|
memcpy(rx, RING_GET_RESPONSE(&queue->rx, i), sizeof(*rx));
|
|
memset(extras, 0, sizeof(rinfo.extras));
|
|
|
|
err = xennet_get_responses(queue, &rinfo, rp, &tmpq);
|
|
|
|
if (unlikely(err)) {
|
|
err:
|
|
while ((skb = __skb_dequeue(&tmpq)))
|
|
__skb_queue_tail(&errq, skb);
|
|
dev->stats.rx_errors++;
|
|
i = queue->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);
|
|
queue->rx.rsp_cons += skb_queue_len(&tmpq);
|
|
goto err;
|
|
}
|
|
}
|
|
|
|
NETFRONT_SKB_CB(skb)->pull_to = rx->status;
|
|
if (NETFRONT_SKB_CB(skb)->pull_to > RX_COPY_THRESHOLD)
|
|
NETFRONT_SKB_CB(skb)->pull_to = RX_COPY_THRESHOLD;
|
|
|
|
skb_shinfo(skb)->frags[0].page_offset = rx->offset;
|
|
skb_frag_size_set(&skb_shinfo(skb)->frags[0], rx->status);
|
|
skb->data_len = rx->status;
|
|
skb->len += rx->status;
|
|
|
|
i = xennet_fill_frags(queue, skb, &tmpq);
|
|
|
|
if (rx->flags & XEN_NETRXF_csum_blank)
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
else if (rx->flags & XEN_NETRXF_data_validated)
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
__skb_queue_tail(&rxq, skb);
|
|
|
|
queue->rx.rsp_cons = ++i;
|
|
work_done++;
|
|
}
|
|
|
|
__skb_queue_purge(&errq);
|
|
|
|
work_done -= handle_incoming_queue(queue, &rxq);
|
|
|
|
/* If we get a callback with very few responses, reduce fill target. */
|
|
/* NB. Note exponential increase, linear decrease. */
|
|
if (((queue->rx.req_prod_pvt - queue->rx.sring->rsp_prod) >
|
|
((3*queue->rx_target) / 4)) &&
|
|
(--queue->rx_target < queue->rx_min_target))
|
|
queue->rx_target = queue->rx_min_target;
|
|
|
|
xennet_alloc_rx_buffers(queue);
|
|
|
|
if (work_done < budget) {
|
|
int more_to_do = 0;
|
|
|
|
napi_gro_flush(napi, false);
|
|
|
|
local_irq_save(flags);
|
|
|
|
RING_FINAL_CHECK_FOR_RESPONSES(&queue->rx, more_to_do);
|
|
if (!more_to_do)
|
|
__napi_complete(napi);
|
|
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
spin_unlock(&queue->rx_lock);
|
|
|
|
return work_done;
|
|
}
|
|
|
|
static int xennet_change_mtu(struct net_device *dev, int mtu)
|
|
{
|
|
int max = xennet_can_sg(dev) ?
|
|
XEN_NETIF_MAX_TX_SIZE - MAX_TCP_HEADER : ETH_DATA_LEN;
|
|
|
|
if (mtu > max)
|
|
return -EINVAL;
|
|
dev->mtu = mtu;
|
|
return 0;
|
|
}
|
|
|
|
static struct rtnl_link_stats64 *xennet_get_stats64(struct net_device *dev,
|
|
struct rtnl_link_stats64 *tot)
|
|
{
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct netfront_stats *stats = per_cpu_ptr(np->stats, cpu);
|
|
u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
|
|
unsigned int start;
|
|
|
|
do {
|
|
start = u64_stats_fetch_begin_irq(&stats->syncp);
|
|
|
|
rx_packets = stats->rx_packets;
|
|
tx_packets = stats->tx_packets;
|
|
rx_bytes = stats->rx_bytes;
|
|
tx_bytes = stats->tx_bytes;
|
|
} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
|
|
|
|
tot->rx_packets += rx_packets;
|
|
tot->tx_packets += tx_packets;
|
|
tot->rx_bytes += rx_bytes;
|
|
tot->tx_bytes += tx_bytes;
|
|
}
|
|
|
|
tot->rx_errors = dev->stats.rx_errors;
|
|
tot->tx_dropped = dev->stats.tx_dropped;
|
|
|
|
return tot;
|
|
}
|
|
|
|
static void xennet_release_tx_bufs(struct netfront_queue *queue)
|
|
{
|
|
struct sk_buff *skb;
|
|
int i;
|
|
|
|
for (i = 0; i < NET_TX_RING_SIZE; i++) {
|
|
/* Skip over entries which are actually freelist references */
|
|
if (skb_entry_is_link(&queue->tx_skbs[i]))
|
|
continue;
|
|
|
|
skb = queue->tx_skbs[i].skb;
|
|
get_page(queue->grant_tx_page[i]);
|
|
gnttab_end_foreign_access(queue->grant_tx_ref[i],
|
|
GNTMAP_readonly,
|
|
(unsigned long)page_address(queue->grant_tx_page[i]));
|
|
queue->grant_tx_page[i] = NULL;
|
|
queue->grant_tx_ref[i] = GRANT_INVALID_REF;
|
|
add_id_to_freelist(&queue->tx_skb_freelist, queue->tx_skbs, i);
|
|
dev_kfree_skb_irq(skb);
|
|
}
|
|
}
|
|
|
|
static void xennet_release_rx_bufs(struct netfront_queue *queue)
|
|
{
|
|
int id, ref;
|
|
|
|
spin_lock_bh(&queue->rx_lock);
|
|
|
|
for (id = 0; id < NET_RX_RING_SIZE; id++) {
|
|
struct sk_buff *skb;
|
|
struct page *page;
|
|
|
|
skb = queue->rx_skbs[id];
|
|
if (!skb)
|
|
continue;
|
|
|
|
ref = queue->grant_rx_ref[id];
|
|
if (ref == GRANT_INVALID_REF)
|
|
continue;
|
|
|
|
page = skb_frag_page(&skb_shinfo(skb)->frags[0]);
|
|
|
|
/* gnttab_end_foreign_access() needs a page ref until
|
|
* foreign access is ended (which may be deferred).
|
|
*/
|
|
get_page(page);
|
|
gnttab_end_foreign_access(ref, 0,
|
|
(unsigned long)page_address(page));
|
|
queue->grant_rx_ref[id] = GRANT_INVALID_REF;
|
|
|
|
kfree_skb(skb);
|
|
}
|
|
|
|
spin_unlock_bh(&queue->rx_lock);
|
|
}
|
|
|
|
static netdev_features_t xennet_fix_features(struct net_device *dev,
|
|
netdev_features_t features)
|
|
{
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
int val;
|
|
|
|
if (features & NETIF_F_SG) {
|
|
if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, "feature-sg",
|
|
"%d", &val) < 0)
|
|
val = 0;
|
|
|
|
if (!val)
|
|
features &= ~NETIF_F_SG;
|
|
}
|
|
|
|
if (features & NETIF_F_IPV6_CSUM) {
|
|
if (xenbus_scanf(XBT_NIL, np->xbdev->otherend,
|
|
"feature-ipv6-csum-offload", "%d", &val) < 0)
|
|
val = 0;
|
|
|
|
if (!val)
|
|
features &= ~NETIF_F_IPV6_CSUM;
|
|
}
|
|
|
|
if (features & NETIF_F_TSO) {
|
|
if (xenbus_scanf(XBT_NIL, np->xbdev->otherend,
|
|
"feature-gso-tcpv4", "%d", &val) < 0)
|
|
val = 0;
|
|
|
|
if (!val)
|
|
features &= ~NETIF_F_TSO;
|
|
}
|
|
|
|
if (features & NETIF_F_TSO6) {
|
|
if (xenbus_scanf(XBT_NIL, np->xbdev->otherend,
|
|
"feature-gso-tcpv6", "%d", &val) < 0)
|
|
val = 0;
|
|
|
|
if (!val)
|
|
features &= ~NETIF_F_TSO6;
|
|
}
|
|
|
|
return features;
|
|
}
|
|
|
|
static int xennet_set_features(struct net_device *dev,
|
|
netdev_features_t features)
|
|
{
|
|
if (!(features & NETIF_F_SG) && dev->mtu > ETH_DATA_LEN) {
|
|
netdev_info(dev, "Reducing MTU because no SG offload");
|
|
dev->mtu = ETH_DATA_LEN;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static irqreturn_t xennet_tx_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct netfront_queue *queue = dev_id;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&queue->tx_lock, flags);
|
|
xennet_tx_buf_gc(queue);
|
|
spin_unlock_irqrestore(&queue->tx_lock, flags);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static irqreturn_t xennet_rx_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct netfront_queue *queue = dev_id;
|
|
struct net_device *dev = queue->info->netdev;
|
|
|
|
if (likely(netif_carrier_ok(dev) &&
|
|
RING_HAS_UNCONSUMED_RESPONSES(&queue->rx)))
|
|
napi_schedule(&queue->napi);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static irqreturn_t xennet_interrupt(int irq, void *dev_id)
|
|
{
|
|
xennet_tx_interrupt(irq, dev_id);
|
|
xennet_rx_interrupt(irq, dev_id);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
static void xennet_poll_controller(struct net_device *dev)
|
|
{
|
|
/* Poll each queue */
|
|
struct netfront_info *info = netdev_priv(dev);
|
|
unsigned int num_queues = dev->real_num_tx_queues;
|
|
unsigned int i;
|
|
for (i = 0; i < num_queues; ++i)
|
|
xennet_interrupt(0, &info->queues[i]);
|
|
}
|
|
#endif
|
|
|
|
static const struct net_device_ops xennet_netdev_ops = {
|
|
.ndo_open = xennet_open,
|
|
.ndo_stop = xennet_close,
|
|
.ndo_start_xmit = xennet_start_xmit,
|
|
.ndo_change_mtu = xennet_change_mtu,
|
|
.ndo_get_stats64 = xennet_get_stats64,
|
|
.ndo_set_mac_address = eth_mac_addr,
|
|
.ndo_validate_addr = eth_validate_addr,
|
|
.ndo_fix_features = xennet_fix_features,
|
|
.ndo_set_features = xennet_set_features,
|
|
.ndo_select_queue = xennet_select_queue,
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
.ndo_poll_controller = xennet_poll_controller,
|
|
#endif
|
|
};
|
|
|
|
static struct net_device *xennet_create_dev(struct xenbus_device *dev)
|
|
{
|
|
int err;
|
|
struct net_device *netdev;
|
|
struct netfront_info *np;
|
|
|
|
netdev = alloc_etherdev_mq(sizeof(struct netfront_info), xennet_max_queues);
|
|
if (!netdev)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
np = netdev_priv(netdev);
|
|
np->xbdev = dev;
|
|
|
|
/* No need to use rtnl_lock() before the call below as it
|
|
* happens before register_netdev().
|
|
*/
|
|
netif_set_real_num_tx_queues(netdev, 0);
|
|
np->queues = NULL;
|
|
|
|
err = -ENOMEM;
|
|
np->stats = netdev_alloc_pcpu_stats(struct netfront_stats);
|
|
if (np->stats == NULL)
|
|
goto exit;
|
|
|
|
netdev->netdev_ops = &xennet_netdev_ops;
|
|
|
|
netdev->features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM |
|
|
NETIF_F_GSO_ROBUST;
|
|
netdev->hw_features = NETIF_F_SG |
|
|
NETIF_F_IPV6_CSUM |
|
|
NETIF_F_TSO | NETIF_F_TSO6;
|
|
|
|
/*
|
|
* Assume that all hw features are available for now. This set
|
|
* will be adjusted by the call to netdev_update_features() in
|
|
* xennet_connect() which is the earliest point where we can
|
|
* negotiate with the backend regarding supported features.
|
|
*/
|
|
netdev->features |= netdev->hw_features;
|
|
|
|
netdev->ethtool_ops = &xennet_ethtool_ops;
|
|
SET_NETDEV_DEV(netdev, &dev->dev);
|
|
|
|
netif_set_gso_max_size(netdev, XEN_NETIF_MAX_TX_SIZE - MAX_TCP_HEADER);
|
|
|
|
np->netdev = netdev;
|
|
|
|
netif_carrier_off(netdev);
|
|
|
|
return netdev;
|
|
|
|
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 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_set_drvdata(&dev->dev, info);
|
|
|
|
err = register_netdev(info->netdev);
|
|
if (err) {
|
|
pr_warn("%s: register_netdev err=%d\n", __func__, err);
|
|
goto fail;
|
|
}
|
|
|
|
err = xennet_sysfs_addif(info->netdev);
|
|
if (err) {
|
|
unregister_netdev(info->netdev);
|
|
pr_warn("%s: add sysfs failed err=%d\n", __func__, err);
|
|
goto fail;
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
free_netdev(netdev);
|
|
dev_set_drvdata(&dev->dev, 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)
|
|
{
|
|
unsigned int i = 0;
|
|
unsigned int num_queues = info->netdev->real_num_tx_queues;
|
|
|
|
netif_carrier_off(info->netdev);
|
|
|
|
for (i = 0; i < num_queues; ++i) {
|
|
struct netfront_queue *queue = &info->queues[i];
|
|
|
|
if (queue->tx_irq && (queue->tx_irq == queue->rx_irq))
|
|
unbind_from_irqhandler(queue->tx_irq, queue);
|
|
if (queue->tx_irq && (queue->tx_irq != queue->rx_irq)) {
|
|
unbind_from_irqhandler(queue->tx_irq, queue);
|
|
unbind_from_irqhandler(queue->rx_irq, queue);
|
|
}
|
|
queue->tx_evtchn = queue->rx_evtchn = 0;
|
|
queue->tx_irq = queue->rx_irq = 0;
|
|
|
|
napi_synchronize(&queue->napi);
|
|
|
|
xennet_release_tx_bufs(queue);
|
|
xennet_release_rx_bufs(queue);
|
|
gnttab_free_grant_references(queue->gref_tx_head);
|
|
gnttab_free_grant_references(queue->gref_rx_head);
|
|
|
|
/* End access and free the pages */
|
|
xennet_end_access(queue->tx_ring_ref, queue->tx.sring);
|
|
xennet_end_access(queue->rx_ring_ref, queue->rx.sring);
|
|
|
|
queue->tx_ring_ref = GRANT_INVALID_REF;
|
|
queue->rx_ring_ref = GRANT_INVALID_REF;
|
|
queue->tx.sring = NULL;
|
|
queue->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_get_drvdata(&dev->dev);
|
|
|
|
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 int setup_netfront_single(struct netfront_queue *queue)
|
|
{
|
|
int err;
|
|
|
|
err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->tx_evtchn);
|
|
if (err < 0)
|
|
goto fail;
|
|
|
|
err = bind_evtchn_to_irqhandler(queue->tx_evtchn,
|
|
xennet_interrupt,
|
|
0, queue->info->netdev->name, queue);
|
|
if (err < 0)
|
|
goto bind_fail;
|
|
queue->rx_evtchn = queue->tx_evtchn;
|
|
queue->rx_irq = queue->tx_irq = err;
|
|
|
|
return 0;
|
|
|
|
bind_fail:
|
|
xenbus_free_evtchn(queue->info->xbdev, queue->tx_evtchn);
|
|
queue->tx_evtchn = 0;
|
|
fail:
|
|
return err;
|
|
}
|
|
|
|
static int setup_netfront_split(struct netfront_queue *queue)
|
|
{
|
|
int err;
|
|
|
|
err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->tx_evtchn);
|
|
if (err < 0)
|
|
goto fail;
|
|
err = xenbus_alloc_evtchn(queue->info->xbdev, &queue->rx_evtchn);
|
|
if (err < 0)
|
|
goto alloc_rx_evtchn_fail;
|
|
|
|
snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name),
|
|
"%s-tx", queue->name);
|
|
err = bind_evtchn_to_irqhandler(queue->tx_evtchn,
|
|
xennet_tx_interrupt,
|
|
0, queue->tx_irq_name, queue);
|
|
if (err < 0)
|
|
goto bind_tx_fail;
|
|
queue->tx_irq = err;
|
|
|
|
snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name),
|
|
"%s-rx", queue->name);
|
|
err = bind_evtchn_to_irqhandler(queue->rx_evtchn,
|
|
xennet_rx_interrupt,
|
|
0, queue->rx_irq_name, queue);
|
|
if (err < 0)
|
|
goto bind_rx_fail;
|
|
queue->rx_irq = err;
|
|
|
|
return 0;
|
|
|
|
bind_rx_fail:
|
|
unbind_from_irqhandler(queue->tx_irq, queue);
|
|
queue->tx_irq = 0;
|
|
bind_tx_fail:
|
|
xenbus_free_evtchn(queue->info->xbdev, queue->rx_evtchn);
|
|
queue->rx_evtchn = 0;
|
|
alloc_rx_evtchn_fail:
|
|
xenbus_free_evtchn(queue->info->xbdev, queue->tx_evtchn);
|
|
queue->tx_evtchn = 0;
|
|
fail:
|
|
return err;
|
|
}
|
|
|
|
static int setup_netfront(struct xenbus_device *dev,
|
|
struct netfront_queue *queue, unsigned int feature_split_evtchn)
|
|
{
|
|
struct xen_netif_tx_sring *txs;
|
|
struct xen_netif_rx_sring *rxs;
|
|
int err;
|
|
|
|
queue->tx_ring_ref = GRANT_INVALID_REF;
|
|
queue->rx_ring_ref = GRANT_INVALID_REF;
|
|
queue->rx.sring = NULL;
|
|
queue->tx.sring = NULL;
|
|
|
|
txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
|
|
if (!txs) {
|
|
err = -ENOMEM;
|
|
xenbus_dev_fatal(dev, err, "allocating tx ring page");
|
|
goto fail;
|
|
}
|
|
SHARED_RING_INIT(txs);
|
|
FRONT_RING_INIT(&queue->tx, txs, PAGE_SIZE);
|
|
|
|
err = xenbus_grant_ring(dev, virt_to_mfn(txs));
|
|
if (err < 0)
|
|
goto grant_tx_ring_fail;
|
|
queue->tx_ring_ref = err;
|
|
|
|
rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
|
|
if (!rxs) {
|
|
err = -ENOMEM;
|
|
xenbus_dev_fatal(dev, err, "allocating rx ring page");
|
|
goto alloc_rx_ring_fail;
|
|
}
|
|
SHARED_RING_INIT(rxs);
|
|
FRONT_RING_INIT(&queue->rx, rxs, PAGE_SIZE);
|
|
|
|
err = xenbus_grant_ring(dev, virt_to_mfn(rxs));
|
|
if (err < 0)
|
|
goto grant_rx_ring_fail;
|
|
queue->rx_ring_ref = err;
|
|
|
|
if (feature_split_evtchn)
|
|
err = setup_netfront_split(queue);
|
|
/* setup single event channel if
|
|
* a) feature-split-event-channels == 0
|
|
* b) feature-split-event-channels == 1 but failed to setup
|
|
*/
|
|
if (!feature_split_evtchn || (feature_split_evtchn && err))
|
|
err = setup_netfront_single(queue);
|
|
|
|
if (err)
|
|
goto alloc_evtchn_fail;
|
|
|
|
return 0;
|
|
|
|
/* If we fail to setup netfront, it is safe to just revoke access to
|
|
* granted pages because backend is not accessing it at this point.
|
|
*/
|
|
alloc_evtchn_fail:
|
|
gnttab_end_foreign_access_ref(queue->rx_ring_ref, 0);
|
|
grant_rx_ring_fail:
|
|
free_page((unsigned long)rxs);
|
|
alloc_rx_ring_fail:
|
|
gnttab_end_foreign_access_ref(queue->tx_ring_ref, 0);
|
|
grant_tx_ring_fail:
|
|
free_page((unsigned long)txs);
|
|
fail:
|
|
return err;
|
|
}
|
|
|
|
/* Queue-specific initialisation
|
|
* This used to be done in xennet_create_dev() but must now
|
|
* be run per-queue.
|
|
*/
|
|
static int xennet_init_queue(struct netfront_queue *queue)
|
|
{
|
|
unsigned short i;
|
|
int err = 0;
|
|
|
|
spin_lock_init(&queue->tx_lock);
|
|
spin_lock_init(&queue->rx_lock);
|
|
|
|
skb_queue_head_init(&queue->rx_batch);
|
|
queue->rx_target = RX_DFL_MIN_TARGET;
|
|
queue->rx_min_target = RX_DFL_MIN_TARGET;
|
|
queue->rx_max_target = RX_MAX_TARGET;
|
|
|
|
init_timer(&queue->rx_refill_timer);
|
|
queue->rx_refill_timer.data = (unsigned long)queue;
|
|
queue->rx_refill_timer.function = rx_refill_timeout;
|
|
|
|
snprintf(queue->name, sizeof(queue->name), "%s-q%u",
|
|
queue->info->netdev->name, queue->id);
|
|
|
|
/* Initialise tx_skbs as a free chain containing every entry. */
|
|
queue->tx_skb_freelist = 0;
|
|
for (i = 0; i < NET_TX_RING_SIZE; i++) {
|
|
skb_entry_set_link(&queue->tx_skbs[i], i+1);
|
|
queue->grant_tx_ref[i] = GRANT_INVALID_REF;
|
|
queue->grant_tx_page[i] = NULL;
|
|
}
|
|
|
|
/* Clear out rx_skbs */
|
|
for (i = 0; i < NET_RX_RING_SIZE; i++) {
|
|
queue->rx_skbs[i] = NULL;
|
|
queue->grant_rx_ref[i] = GRANT_INVALID_REF;
|
|
}
|
|
|
|
/* A grant for every tx ring slot */
|
|
if (gnttab_alloc_grant_references(TX_MAX_TARGET,
|
|
&queue->gref_tx_head) < 0) {
|
|
pr_alert("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,
|
|
&queue->gref_rx_head) < 0) {
|
|
pr_alert("can't alloc rx grant refs\n");
|
|
err = -ENOMEM;
|
|
goto exit_free_tx;
|
|
}
|
|
|
|
return 0;
|
|
|
|
exit_free_tx:
|
|
gnttab_free_grant_references(queue->gref_tx_head);
|
|
exit:
|
|
return err;
|
|
}
|
|
|
|
static int write_queue_xenstore_keys(struct netfront_queue *queue,
|
|
struct xenbus_transaction *xbt, int write_hierarchical)
|
|
{
|
|
/* Write the queue-specific keys into XenStore in the traditional
|
|
* way for a single queue, or in a queue subkeys for multiple
|
|
* queues.
|
|
*/
|
|
struct xenbus_device *dev = queue->info->xbdev;
|
|
int err;
|
|
const char *message;
|
|
char *path;
|
|
size_t pathsize;
|
|
|
|
/* Choose the correct place to write the keys */
|
|
if (write_hierarchical) {
|
|
pathsize = strlen(dev->nodename) + 10;
|
|
path = kzalloc(pathsize, GFP_KERNEL);
|
|
if (!path) {
|
|
err = -ENOMEM;
|
|
message = "out of memory while writing ring references";
|
|
goto error;
|
|
}
|
|
snprintf(path, pathsize, "%s/queue-%u",
|
|
dev->nodename, queue->id);
|
|
} else {
|
|
path = (char *)dev->nodename;
|
|
}
|
|
|
|
/* Write ring references */
|
|
err = xenbus_printf(*xbt, path, "tx-ring-ref", "%u",
|
|
queue->tx_ring_ref);
|
|
if (err) {
|
|
message = "writing tx-ring-ref";
|
|
goto error;
|
|
}
|
|
|
|
err = xenbus_printf(*xbt, path, "rx-ring-ref", "%u",
|
|
queue->rx_ring_ref);
|
|
if (err) {
|
|
message = "writing rx-ring-ref";
|
|
goto error;
|
|
}
|
|
|
|
/* Write event channels; taking into account both shared
|
|
* and split event channel scenarios.
|
|
*/
|
|
if (queue->tx_evtchn == queue->rx_evtchn) {
|
|
/* Shared event channel */
|
|
err = xenbus_printf(*xbt, path,
|
|
"event-channel", "%u", queue->tx_evtchn);
|
|
if (err) {
|
|
message = "writing event-channel";
|
|
goto error;
|
|
}
|
|
} else {
|
|
/* Split event channels */
|
|
err = xenbus_printf(*xbt, path,
|
|
"event-channel-tx", "%u", queue->tx_evtchn);
|
|
if (err) {
|
|
message = "writing event-channel-tx";
|
|
goto error;
|
|
}
|
|
|
|
err = xenbus_printf(*xbt, path,
|
|
"event-channel-rx", "%u", queue->rx_evtchn);
|
|
if (err) {
|
|
message = "writing event-channel-rx";
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
if (write_hierarchical)
|
|
kfree(path);
|
|
return 0;
|
|
|
|
error:
|
|
if (write_hierarchical)
|
|
kfree(path);
|
|
xenbus_dev_fatal(dev, err, "%s", message);
|
|
return err;
|
|
}
|
|
|
|
static void xennet_destroy_queues(struct netfront_info *info)
|
|
{
|
|
unsigned int i;
|
|
|
|
rtnl_lock();
|
|
|
|
for (i = 0; i < info->netdev->real_num_tx_queues; i++) {
|
|
struct netfront_queue *queue = &info->queues[i];
|
|
|
|
if (netif_running(info->netdev))
|
|
napi_disable(&queue->napi);
|
|
netif_napi_del(&queue->napi);
|
|
}
|
|
|
|
rtnl_unlock();
|
|
|
|
kfree(info->queues);
|
|
info->queues = NULL;
|
|
}
|
|
|
|
static int xennet_create_queues(struct netfront_info *info,
|
|
unsigned int num_queues)
|
|
{
|
|
unsigned int i;
|
|
int ret;
|
|
|
|
info->queues = kcalloc(num_queues, sizeof(struct netfront_queue),
|
|
GFP_KERNEL);
|
|
if (!info->queues)
|
|
return -ENOMEM;
|
|
|
|
rtnl_lock();
|
|
|
|
for (i = 0; i < num_queues; i++) {
|
|
struct netfront_queue *queue = &info->queues[i];
|
|
|
|
queue->id = i;
|
|
queue->info = info;
|
|
|
|
ret = xennet_init_queue(queue);
|
|
if (ret < 0) {
|
|
dev_warn(&info->netdev->dev,
|
|
"only created %d queues\n", i);
|
|
num_queues = i;
|
|
break;
|
|
}
|
|
|
|
netif_napi_add(queue->info->netdev, &queue->napi,
|
|
xennet_poll, 64);
|
|
if (netif_running(info->netdev))
|
|
napi_enable(&queue->napi);
|
|
}
|
|
|
|
netif_set_real_num_tx_queues(info->netdev, num_queues);
|
|
|
|
rtnl_unlock();
|
|
|
|
if (num_queues == 0) {
|
|
dev_err(&info->netdev->dev, "no queues\n");
|
|
return -EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Common code used when first setting up, and when resuming. */
|
|
static int talk_to_netback(struct xenbus_device *dev,
|
|
struct netfront_info *info)
|
|
{
|
|
const char *message;
|
|
struct xenbus_transaction xbt;
|
|
int err;
|
|
unsigned int feature_split_evtchn;
|
|
unsigned int i = 0;
|
|
unsigned int max_queues = 0;
|
|
struct netfront_queue *queue = NULL;
|
|
unsigned int num_queues = 1;
|
|
|
|
info->netdev->irq = 0;
|
|
|
|
/* Check if backend supports multiple queues */
|
|
err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
|
|
"multi-queue-max-queues", "%u", &max_queues);
|
|
if (err < 0)
|
|
max_queues = 1;
|
|
num_queues = min(max_queues, xennet_max_queues);
|
|
|
|
/* Check feature-split-event-channels */
|
|
err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
|
|
"feature-split-event-channels", "%u",
|
|
&feature_split_evtchn);
|
|
if (err < 0)
|
|
feature_split_evtchn = 0;
|
|
|
|
/* Read mac addr. */
|
|
err = xen_net_read_mac(dev, info->netdev->dev_addr);
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
|
|
goto out;
|
|
}
|
|
|
|
if (info->queues)
|
|
xennet_destroy_queues(info);
|
|
|
|
err = xennet_create_queues(info, num_queues);
|
|
if (err < 0)
|
|
goto destroy_ring;
|
|
|
|
/* Create shared ring, alloc event channel -- for each queue */
|
|
for (i = 0; i < num_queues; ++i) {
|
|
queue = &info->queues[i];
|
|
err = setup_netfront(dev, queue, feature_split_evtchn);
|
|
if (err) {
|
|
/* setup_netfront() will tidy up the current
|
|
* queue on error, but we need to clean up
|
|
* those already allocated.
|
|
*/
|
|
if (i > 0) {
|
|
rtnl_lock();
|
|
netif_set_real_num_tx_queues(info->netdev, i);
|
|
rtnl_unlock();
|
|
goto destroy_ring;
|
|
} else {
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
|
|
again:
|
|
err = xenbus_transaction_start(&xbt);
|
|
if (err) {
|
|
xenbus_dev_fatal(dev, err, "starting transaction");
|
|
goto destroy_ring;
|
|
}
|
|
|
|
if (num_queues == 1) {
|
|
err = write_queue_xenstore_keys(&info->queues[0], &xbt, 0); /* flat */
|
|
if (err)
|
|
goto abort_transaction_no_dev_fatal;
|
|
} else {
|
|
/* Write the number of queues */
|
|
err = xenbus_printf(xbt, dev->nodename, "multi-queue-num-queues",
|
|
"%u", num_queues);
|
|
if (err) {
|
|
message = "writing multi-queue-num-queues";
|
|
goto abort_transaction_no_dev_fatal;
|
|
}
|
|
|
|
/* Write the keys for each queue */
|
|
for (i = 0; i < num_queues; ++i) {
|
|
queue = &info->queues[i];
|
|
err = write_queue_xenstore_keys(queue, &xbt, 1); /* hierarchical */
|
|
if (err)
|
|
goto abort_transaction_no_dev_fatal;
|
|
}
|
|
}
|
|
|
|
/* The remaining keys are not queue-specific */
|
|
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_write(xbt, dev->nodename, "feature-gso-tcpv6", "1");
|
|
if (err) {
|
|
message = "writing feature-gso-tcpv6";
|
|
goto abort_transaction;
|
|
}
|
|
|
|
err = xenbus_write(xbt, dev->nodename, "feature-ipv6-csum-offload",
|
|
"1");
|
|
if (err) {
|
|
message = "writing feature-ipv6-csum-offload";
|
|
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_dev_fatal(dev, err, "%s", message);
|
|
abort_transaction_no_dev_fatal:
|
|
xenbus_transaction_end(xbt, 1);
|
|
destroy_ring:
|
|
xennet_disconnect_backend(info);
|
|
kfree(info->queues);
|
|
info->queues = NULL;
|
|
rtnl_lock();
|
|
netif_set_real_num_tx_queues(info->netdev, 0);
|
|
rtnl_unlock();
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static int xennet_connect(struct net_device *dev)
|
|
{
|
|
struct netfront_info *np = netdev_priv(dev);
|
|
unsigned int num_queues = 0;
|
|
int err;
|
|
unsigned int feature_rx_copy;
|
|
unsigned int j = 0;
|
|
struct netfront_queue *queue = NULL;
|
|
|
|
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 receive path\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
err = talk_to_netback(np->xbdev, np);
|
|
if (err)
|
|
return err;
|
|
|
|
/* talk_to_netback() sets the correct number of queues */
|
|
num_queues = dev->real_num_tx_queues;
|
|
|
|
rtnl_lock();
|
|
netdev_update_features(dev);
|
|
rtnl_unlock();
|
|
|
|
/*
|
|
* 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);
|
|
for (j = 0; j < num_queues; ++j) {
|
|
queue = &np->queues[j];
|
|
|
|
notify_remote_via_irq(queue->tx_irq);
|
|
if (queue->tx_irq != queue->rx_irq)
|
|
notify_remote_via_irq(queue->rx_irq);
|
|
|
|
spin_lock_irq(&queue->tx_lock);
|
|
xennet_tx_buf_gc(queue);
|
|
spin_unlock_irq(&queue->tx_lock);
|
|
|
|
spin_lock_bh(&queue->rx_lock);
|
|
xennet_alloc_rx_buffers(queue);
|
|
spin_unlock_bh(&queue->rx_lock);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Callback received when the backend's state changes.
|
|
*/
|
|
static void netback_changed(struct xenbus_device *dev,
|
|
enum xenbus_state backend_state)
|
|
{
|
|
struct netfront_info *np = dev_get_drvdata(&dev->dev);
|
|
struct net_device *netdev = np->netdev;
|
|
|
|
dev_dbg(&dev->dev, "%s\n", xenbus_strstate(backend_state));
|
|
|
|
switch (backend_state) {
|
|
case XenbusStateInitialising:
|
|
case XenbusStateInitialised:
|
|
case XenbusStateReconfiguring:
|
|
case XenbusStateReconfigured:
|
|
case XenbusStateUnknown:
|
|
break;
|
|
|
|
case XenbusStateInitWait:
|
|
if (dev->state != XenbusStateInitialising)
|
|
break;
|
|
if (xennet_connect(netdev) != 0)
|
|
break;
|
|
xenbus_switch_state(dev, XenbusStateConnected);
|
|
break;
|
|
|
|
case XenbusStateConnected:
|
|
netdev_notify_peers(netdev);
|
|
break;
|
|
|
|
case XenbusStateClosed:
|
|
if (dev->state == XenbusStateClosed)
|
|
break;
|
|
/* Missed the backend's CLOSING state -- fallthrough */
|
|
case XenbusStateClosing:
|
|
xenbus_frontend_closed(dev);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static const struct xennet_stat {
|
|
char name[ETH_GSTRING_LEN];
|
|
u16 offset;
|
|
} xennet_stats[] = {
|
|
{
|
|
"rx_gso_checksum_fixup",
|
|
offsetof(struct netfront_info, rx_gso_checksum_fixup)
|
|
},
|
|
};
|
|
|
|
static int xennet_get_sset_count(struct net_device *dev, int string_set)
|
|
{
|
|
switch (string_set) {
|
|
case ETH_SS_STATS:
|
|
return ARRAY_SIZE(xennet_stats);
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static void xennet_get_ethtool_stats(struct net_device *dev,
|
|
struct ethtool_stats *stats, u64 * data)
|
|
{
|
|
void *np = netdev_priv(dev);
|
|
int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(xennet_stats); i++)
|
|
data[i] = atomic_read((atomic_t *)(np + xennet_stats[i].offset));
|
|
}
|
|
|
|
static void xennet_get_strings(struct net_device *dev, u32 stringset, u8 * data)
|
|
{
|
|
int i;
|
|
|
|
switch (stringset) {
|
|
case ETH_SS_STATS:
|
|
for (i = 0; i < ARRAY_SIZE(xennet_stats); i++)
|
|
memcpy(data + i * ETH_GSTRING_LEN,
|
|
xennet_stats[i].name, ETH_GSTRING_LEN);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static const struct ethtool_ops xennet_ethtool_ops =
|
|
{
|
|
.get_link = ethtool_op_get_link,
|
|
|
|
.get_sset_count = xennet_get_sset_count,
|
|
.get_ethtool_stats = xennet_get_ethtool_stats,
|
|
.get_strings = xennet_get_strings,
|
|
};
|
|
|
|
#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);
|
|
unsigned int num_queues = netdev->real_num_tx_queues;
|
|
|
|
if (num_queues)
|
|
return sprintf(buf, "%u\n", info->queues[0].rx_min_target);
|
|
else
|
|
return sprintf(buf, "%u\n", 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);
|
|
unsigned int num_queues = netdev->real_num_tx_queues;
|
|
char *endp;
|
|
unsigned long target;
|
|
unsigned int i;
|
|
struct netfront_queue *queue;
|
|
|
|
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;
|
|
|
|
for (i = 0; i < num_queues; ++i) {
|
|
queue = &np->queues[i];
|
|
spin_lock_bh(&queue->rx_lock);
|
|
if (target > queue->rx_max_target)
|
|
queue->rx_max_target = target;
|
|
queue->rx_min_target = target;
|
|
if (target > queue->rx_target)
|
|
queue->rx_target = target;
|
|
|
|
xennet_alloc_rx_buffers(queue);
|
|
|
|
spin_unlock_bh(&queue->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);
|
|
unsigned int num_queues = netdev->real_num_tx_queues;
|
|
|
|
if (num_queues)
|
|
return sprintf(buf, "%u\n", info->queues[0].rx_max_target);
|
|
else
|
|
return sprintf(buf, "%u\n", 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);
|
|
unsigned int num_queues = netdev->real_num_tx_queues;
|
|
char *endp;
|
|
unsigned long target;
|
|
unsigned int i = 0;
|
|
struct netfront_queue *queue = NULL;
|
|
|
|
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;
|
|
|
|
for (i = 0; i < num_queues; ++i) {
|
|
queue = &np->queues[i];
|
|
spin_lock_bh(&queue->rx_lock);
|
|
if (target < queue->rx_min_target)
|
|
queue->rx_min_target = target;
|
|
queue->rx_max_target = target;
|
|
if (target < queue->rx_target)
|
|
queue->rx_target = target;
|
|
|
|
xennet_alloc_rx_buffers(queue);
|
|
|
|
spin_unlock_bh(&queue->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);
|
|
unsigned int num_queues = netdev->real_num_tx_queues;
|
|
|
|
if (num_queues)
|
|
return sprintf(buf, "%u\n", info->queues[0].rx_target);
|
|
else
|
|
return sprintf(buf, "0\n");
|
|
}
|
|
|
|
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 const struct xenbus_device_id netfront_ids[] = {
|
|
{ "vif" },
|
|
{ "" }
|
|
};
|
|
|
|
|
|
static int xennet_remove(struct xenbus_device *dev)
|
|
{
|
|
struct netfront_info *info = dev_get_drvdata(&dev->dev);
|
|
unsigned int num_queues = info->netdev->real_num_tx_queues;
|
|
struct netfront_queue *queue = NULL;
|
|
unsigned int i = 0;
|
|
|
|
dev_dbg(&dev->dev, "%s\n", dev->nodename);
|
|
|
|
xennet_disconnect_backend(info);
|
|
|
|
xennet_sysfs_delif(info->netdev);
|
|
|
|
unregister_netdev(info->netdev);
|
|
|
|
for (i = 0; i < num_queues; ++i) {
|
|
queue = &info->queues[i];
|
|
del_timer_sync(&queue->rx_refill_timer);
|
|
}
|
|
|
|
if (num_queues) {
|
|
kfree(info->queues);
|
|
info->queues = NULL;
|
|
}
|
|
|
|
free_percpu(info->stats);
|
|
|
|
free_netdev(info->netdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static DEFINE_XENBUS_DRIVER(netfront, ,
|
|
.probe = netfront_probe,
|
|
.remove = xennet_remove,
|
|
.resume = netfront_resume,
|
|
.otherend_changed = netback_changed,
|
|
);
|
|
|
|
static int __init netif_init(void)
|
|
{
|
|
if (!xen_domain())
|
|
return -ENODEV;
|
|
|
|
if (!xen_has_pv_nic_devices())
|
|
return -ENODEV;
|
|
|
|
pr_info("Initialising Xen virtual ethernet driver\n");
|
|
|
|
/* Allow as many queues as there are CPUs, by default */
|
|
xennet_max_queues = num_online_cpus();
|
|
|
|
return xenbus_register_frontend(&netfront_driver);
|
|
}
|
|
module_init(netif_init);
|
|
|
|
|
|
static void __exit netif_exit(void)
|
|
{
|
|
xenbus_unregister_driver(&netfront_driver);
|
|
}
|
|
module_exit(netif_exit);
|
|
|
|
MODULE_DESCRIPTION("Xen virtual network device frontend");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("xen:vif");
|
|
MODULE_ALIAS("xennet");
|