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06d381484f
* 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: net: xen-netback: use API provided by xenbus module to map rings block: xen-blkback: use API provided by xenbus module to map rings xen: use generic functions instead of xen_{alloc, free}_vm_area()
1713 lines
42 KiB
C
1713 lines
42 KiB
C
/*
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* Back-end of the driver for virtual network devices. This portion of the
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* driver exports a 'unified' network-device interface that can be accessed
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* by any operating system that implements a compatible front end. A
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* reference front-end implementation can be found in:
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* drivers/net/xen-netfront.c
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*
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* Copyright (c) 2002-2005, K A Fraser
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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 "common.h"
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#include <linux/kthread.h>
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#include <linux/if_vlan.h>
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#include <linux/udp.h>
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#include <net/tcp.h>
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#include <xen/events.h>
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#include <xen/interface/memory.h>
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#include <asm/xen/hypercall.h>
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#include <asm/xen/page.h>
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struct pending_tx_info {
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struct xen_netif_tx_request req;
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struct xenvif *vif;
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};
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typedef unsigned int pending_ring_idx_t;
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struct netbk_rx_meta {
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int id;
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int size;
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int gso_size;
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};
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#define MAX_PENDING_REQS 256
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/* Discriminate from any valid pending_idx value. */
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#define INVALID_PENDING_IDX 0xFFFF
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#define MAX_BUFFER_OFFSET PAGE_SIZE
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/* extra field used in struct page */
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union page_ext {
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struct {
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#if BITS_PER_LONG < 64
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#define IDX_WIDTH 8
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#define GROUP_WIDTH (BITS_PER_LONG - IDX_WIDTH)
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unsigned int group:GROUP_WIDTH;
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unsigned int idx:IDX_WIDTH;
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#else
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unsigned int group, idx;
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#endif
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} e;
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void *mapping;
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};
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struct xen_netbk {
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wait_queue_head_t wq;
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struct task_struct *task;
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struct sk_buff_head rx_queue;
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struct sk_buff_head tx_queue;
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struct timer_list net_timer;
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struct page *mmap_pages[MAX_PENDING_REQS];
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pending_ring_idx_t pending_prod;
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pending_ring_idx_t pending_cons;
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struct list_head net_schedule_list;
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/* Protect the net_schedule_list in netif. */
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spinlock_t net_schedule_list_lock;
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atomic_t netfront_count;
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struct pending_tx_info pending_tx_info[MAX_PENDING_REQS];
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struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS];
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u16 pending_ring[MAX_PENDING_REQS];
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/*
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* Given MAX_BUFFER_OFFSET of 4096 the worst case is that each
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* head/fragment page uses 2 copy operations because it
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* straddles two buffers in the frontend.
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*/
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struct gnttab_copy grant_copy_op[2*XEN_NETIF_RX_RING_SIZE];
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struct netbk_rx_meta meta[2*XEN_NETIF_RX_RING_SIZE];
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};
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static struct xen_netbk *xen_netbk;
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static int xen_netbk_group_nr;
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void xen_netbk_add_xenvif(struct xenvif *vif)
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{
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int i;
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int min_netfront_count;
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int min_group = 0;
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struct xen_netbk *netbk;
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min_netfront_count = atomic_read(&xen_netbk[0].netfront_count);
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for (i = 0; i < xen_netbk_group_nr; i++) {
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int netfront_count = atomic_read(&xen_netbk[i].netfront_count);
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if (netfront_count < min_netfront_count) {
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min_group = i;
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min_netfront_count = netfront_count;
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}
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}
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netbk = &xen_netbk[min_group];
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vif->netbk = netbk;
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atomic_inc(&netbk->netfront_count);
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}
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void xen_netbk_remove_xenvif(struct xenvif *vif)
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{
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struct xen_netbk *netbk = vif->netbk;
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vif->netbk = NULL;
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atomic_dec(&netbk->netfront_count);
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}
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static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx);
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static void make_tx_response(struct xenvif *vif,
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struct xen_netif_tx_request *txp,
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s8 st);
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static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif,
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u16 id,
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s8 st,
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u16 offset,
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u16 size,
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u16 flags);
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static inline unsigned long idx_to_pfn(struct xen_netbk *netbk,
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u16 idx)
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{
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return page_to_pfn(netbk->mmap_pages[idx]);
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}
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static inline unsigned long idx_to_kaddr(struct xen_netbk *netbk,
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u16 idx)
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{
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return (unsigned long)pfn_to_kaddr(idx_to_pfn(netbk, idx));
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}
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/* extra field used in struct page */
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static inline void set_page_ext(struct page *pg, struct xen_netbk *netbk,
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unsigned int idx)
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{
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unsigned int group = netbk - xen_netbk;
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union page_ext ext = { .e = { .group = group + 1, .idx = idx } };
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BUILD_BUG_ON(sizeof(ext) > sizeof(ext.mapping));
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pg->mapping = ext.mapping;
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}
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static int get_page_ext(struct page *pg,
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unsigned int *pgroup, unsigned int *pidx)
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{
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union page_ext ext = { .mapping = pg->mapping };
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struct xen_netbk *netbk;
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unsigned int group, idx;
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group = ext.e.group - 1;
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if (group < 0 || group >= xen_netbk_group_nr)
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return 0;
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netbk = &xen_netbk[group];
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idx = ext.e.idx;
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if ((idx < 0) || (idx >= MAX_PENDING_REQS))
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return 0;
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if (netbk->mmap_pages[idx] != pg)
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return 0;
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*pgroup = group;
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*pidx = idx;
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return 1;
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}
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/*
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* This is the amount of packet we copy rather than map, so that the
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* guest can't fiddle with the contents of the headers while we do
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* packet processing on them (netfilter, routing, etc).
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*/
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#define PKT_PROT_LEN (ETH_HLEN + \
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VLAN_HLEN + \
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sizeof(struct iphdr) + MAX_IPOPTLEN + \
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sizeof(struct tcphdr) + MAX_TCP_OPTION_SPACE)
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static u16 frag_get_pending_idx(skb_frag_t *frag)
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{
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return (u16)frag->page_offset;
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}
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static void frag_set_pending_idx(skb_frag_t *frag, u16 pending_idx)
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{
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frag->page_offset = pending_idx;
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}
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static inline pending_ring_idx_t pending_index(unsigned i)
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{
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return i & (MAX_PENDING_REQS-1);
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}
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static inline pending_ring_idx_t nr_pending_reqs(struct xen_netbk *netbk)
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{
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return MAX_PENDING_REQS -
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netbk->pending_prod + netbk->pending_cons;
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}
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static void xen_netbk_kick_thread(struct xen_netbk *netbk)
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{
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wake_up(&netbk->wq);
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}
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static int max_required_rx_slots(struct xenvif *vif)
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{
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int max = DIV_ROUND_UP(vif->dev->mtu, PAGE_SIZE);
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if (vif->can_sg || vif->gso || vif->gso_prefix)
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max += MAX_SKB_FRAGS + 1; /* extra_info + frags */
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return max;
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}
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int xen_netbk_rx_ring_full(struct xenvif *vif)
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{
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RING_IDX peek = vif->rx_req_cons_peek;
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RING_IDX needed = max_required_rx_slots(vif);
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return ((vif->rx.sring->req_prod - peek) < needed) ||
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((vif->rx.rsp_prod_pvt + XEN_NETIF_RX_RING_SIZE - peek) < needed);
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}
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int xen_netbk_must_stop_queue(struct xenvif *vif)
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{
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if (!xen_netbk_rx_ring_full(vif))
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return 0;
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vif->rx.sring->req_event = vif->rx_req_cons_peek +
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max_required_rx_slots(vif);
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mb(); /* request notification /then/ check the queue */
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return xen_netbk_rx_ring_full(vif);
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}
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/*
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* Returns true if we should start a new receive buffer instead of
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* adding 'size' bytes to a buffer which currently contains 'offset'
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* bytes.
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*/
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static bool start_new_rx_buffer(int offset, unsigned long size, int head)
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{
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/* simple case: we have completely filled the current buffer. */
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if (offset == MAX_BUFFER_OFFSET)
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return true;
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/*
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* complex case: start a fresh buffer if the current frag
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* would overflow the current buffer but only if:
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* (i) this frag would fit completely in the next buffer
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* and (ii) there is already some data in the current buffer
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* and (iii) this is not the head buffer.
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*
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* Where:
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* - (i) stops us splitting a frag into two copies
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* unless the frag is too large for a single buffer.
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* - (ii) stops us from leaving a buffer pointlessly empty.
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* - (iii) stops us leaving the first buffer
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* empty. Strictly speaking this is already covered
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* by (ii) but is explicitly checked because
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* netfront relies on the first buffer being
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* non-empty and can crash otherwise.
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*
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* This means we will effectively linearise small
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* frags but do not needlessly split large buffers
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* into multiple copies tend to give large frags their
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* own buffers as before.
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*/
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if ((offset + size > MAX_BUFFER_OFFSET) &&
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(size <= MAX_BUFFER_OFFSET) && offset && !head)
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return true;
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return false;
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}
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/*
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* Figure out how many ring slots we're going to need to send @skb to
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* the guest. This function is essentially a dry run of
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* netbk_gop_frag_copy.
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*/
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unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb)
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{
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unsigned int count;
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int i, copy_off;
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count = DIV_ROUND_UP(
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offset_in_page(skb->data)+skb_headlen(skb), PAGE_SIZE);
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copy_off = skb_headlen(skb) % PAGE_SIZE;
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if (skb_shinfo(skb)->gso_size)
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count++;
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for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
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unsigned long size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
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unsigned long bytes;
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while (size > 0) {
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BUG_ON(copy_off > MAX_BUFFER_OFFSET);
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if (start_new_rx_buffer(copy_off, size, 0)) {
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count++;
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copy_off = 0;
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}
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bytes = size;
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if (copy_off + bytes > MAX_BUFFER_OFFSET)
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bytes = MAX_BUFFER_OFFSET - copy_off;
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copy_off += bytes;
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size -= bytes;
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}
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}
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return count;
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}
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struct netrx_pending_operations {
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unsigned copy_prod, copy_cons;
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unsigned meta_prod, meta_cons;
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struct gnttab_copy *copy;
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struct netbk_rx_meta *meta;
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int copy_off;
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grant_ref_t copy_gref;
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};
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static struct netbk_rx_meta *get_next_rx_buffer(struct xenvif *vif,
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struct netrx_pending_operations *npo)
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{
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struct netbk_rx_meta *meta;
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struct xen_netif_rx_request *req;
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req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++);
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meta = npo->meta + npo->meta_prod++;
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meta->gso_size = 0;
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meta->size = 0;
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meta->id = req->id;
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npo->copy_off = 0;
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npo->copy_gref = req->gref;
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return meta;
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}
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/*
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* Set up the grant operations for this fragment. If it's a flipping
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* interface, we also set up the unmap request from here.
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*/
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static void netbk_gop_frag_copy(struct xenvif *vif, struct sk_buff *skb,
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struct netrx_pending_operations *npo,
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struct page *page, unsigned long size,
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unsigned long offset, int *head)
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{
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struct gnttab_copy *copy_gop;
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struct netbk_rx_meta *meta;
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/*
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* These variables a used iff get_page_ext returns true,
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* in which case they are guaranteed to be initialized.
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*/
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unsigned int uninitialized_var(group), uninitialized_var(idx);
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int foreign = get_page_ext(page, &group, &idx);
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unsigned long bytes;
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/* Data must not cross a page boundary. */
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BUG_ON(size + offset > PAGE_SIZE);
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meta = npo->meta + npo->meta_prod - 1;
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while (size > 0) {
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BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET);
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if (start_new_rx_buffer(npo->copy_off, size, *head)) {
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/*
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* Netfront requires there to be some data in the head
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* buffer.
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*/
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BUG_ON(*head);
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meta = get_next_rx_buffer(vif, npo);
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}
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bytes = size;
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if (npo->copy_off + bytes > MAX_BUFFER_OFFSET)
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bytes = MAX_BUFFER_OFFSET - npo->copy_off;
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copy_gop = npo->copy + npo->copy_prod++;
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copy_gop->flags = GNTCOPY_dest_gref;
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if (foreign) {
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struct xen_netbk *netbk = &xen_netbk[group];
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struct pending_tx_info *src_pend;
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src_pend = &netbk->pending_tx_info[idx];
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copy_gop->source.domid = src_pend->vif->domid;
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copy_gop->source.u.ref = src_pend->req.gref;
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copy_gop->flags |= GNTCOPY_source_gref;
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} else {
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void *vaddr = page_address(page);
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copy_gop->source.domid = DOMID_SELF;
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copy_gop->source.u.gmfn = virt_to_mfn(vaddr);
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}
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copy_gop->source.offset = offset;
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copy_gop->dest.domid = vif->domid;
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copy_gop->dest.offset = npo->copy_off;
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copy_gop->dest.u.ref = npo->copy_gref;
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copy_gop->len = bytes;
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npo->copy_off += bytes;
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meta->size += bytes;
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offset += bytes;
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size -= bytes;
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/* Leave a gap for the GSO descriptor. */
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if (*head && skb_shinfo(skb)->gso_size && !vif->gso_prefix)
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vif->rx.req_cons++;
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*head = 0; /* There must be something in this buffer now. */
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}
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}
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|
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/*
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* Prepare an SKB to be transmitted to the frontend.
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*
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* This function is responsible for allocating grant operations, meta
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* structures, etc.
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*
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* It returns the number of meta structures consumed. The number of
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* ring slots used is always equal to the number of meta slots used
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* plus the number of GSO descriptors used. Currently, we use either
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* zero GSO descriptors (for non-GSO packets) or one descriptor (for
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* frontend-side LRO).
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*/
|
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static int netbk_gop_skb(struct sk_buff *skb,
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struct netrx_pending_operations *npo)
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{
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struct xenvif *vif = netdev_priv(skb->dev);
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int nr_frags = skb_shinfo(skb)->nr_frags;
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int i;
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struct xen_netif_rx_request *req;
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struct netbk_rx_meta *meta;
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unsigned char *data;
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int head = 1;
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int old_meta_prod;
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old_meta_prod = npo->meta_prod;
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/* Set up a GSO prefix descriptor, if necessary */
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if (skb_shinfo(skb)->gso_size && vif->gso_prefix) {
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req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++);
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meta = npo->meta + npo->meta_prod++;
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meta->gso_size = skb_shinfo(skb)->gso_size;
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meta->size = 0;
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meta->id = req->id;
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}
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req = RING_GET_REQUEST(&vif->rx, vif->rx.req_cons++);
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meta = npo->meta + npo->meta_prod++;
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if (!vif->gso_prefix)
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meta->gso_size = skb_shinfo(skb)->gso_size;
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else
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meta->gso_size = 0;
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|
|
|
meta->size = 0;
|
|
meta->id = req->id;
|
|
npo->copy_off = 0;
|
|
npo->copy_gref = req->gref;
|
|
|
|
data = skb->data;
|
|
while (data < skb_tail_pointer(skb)) {
|
|
unsigned int offset = offset_in_page(data);
|
|
unsigned int len = PAGE_SIZE - offset;
|
|
|
|
if (data + len > skb_tail_pointer(skb))
|
|
len = skb_tail_pointer(skb) - data;
|
|
|
|
netbk_gop_frag_copy(vif, skb, npo,
|
|
virt_to_page(data), len, offset, &head);
|
|
data += len;
|
|
}
|
|
|
|
for (i = 0; i < nr_frags; i++) {
|
|
netbk_gop_frag_copy(vif, skb, npo,
|
|
skb_frag_page(&skb_shinfo(skb)->frags[i]),
|
|
skb_frag_size(&skb_shinfo(skb)->frags[i]),
|
|
skb_shinfo(skb)->frags[i].page_offset,
|
|
&head);
|
|
}
|
|
|
|
return npo->meta_prod - old_meta_prod;
|
|
}
|
|
|
|
/*
|
|
* This is a twin to netbk_gop_skb. Assume that netbk_gop_skb was
|
|
* used to set up the operations on the top of
|
|
* netrx_pending_operations, which have since been done. Check that
|
|
* they didn't give any errors and advance over them.
|
|
*/
|
|
static int netbk_check_gop(struct xenvif *vif, int nr_meta_slots,
|
|
struct netrx_pending_operations *npo)
|
|
{
|
|
struct gnttab_copy *copy_op;
|
|
int status = XEN_NETIF_RSP_OKAY;
|
|
int i;
|
|
|
|
for (i = 0; i < nr_meta_slots; i++) {
|
|
copy_op = npo->copy + npo->copy_cons++;
|
|
if (copy_op->status != GNTST_okay) {
|
|
netdev_dbg(vif->dev,
|
|
"Bad status %d from copy to DOM%d.\n",
|
|
copy_op->status, vif->domid);
|
|
status = XEN_NETIF_RSP_ERROR;
|
|
}
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
static void netbk_add_frag_responses(struct xenvif *vif, int status,
|
|
struct netbk_rx_meta *meta,
|
|
int nr_meta_slots)
|
|
{
|
|
int i;
|
|
unsigned long offset;
|
|
|
|
/* No fragments used */
|
|
if (nr_meta_slots <= 1)
|
|
return;
|
|
|
|
nr_meta_slots--;
|
|
|
|
for (i = 0; i < nr_meta_slots; i++) {
|
|
int flags;
|
|
if (i == nr_meta_slots - 1)
|
|
flags = 0;
|
|
else
|
|
flags = XEN_NETRXF_more_data;
|
|
|
|
offset = 0;
|
|
make_rx_response(vif, meta[i].id, status, offset,
|
|
meta[i].size, flags);
|
|
}
|
|
}
|
|
|
|
struct skb_cb_overlay {
|
|
int meta_slots_used;
|
|
};
|
|
|
|
static void xen_netbk_rx_action(struct xen_netbk *netbk)
|
|
{
|
|
struct xenvif *vif = NULL, *tmp;
|
|
s8 status;
|
|
u16 irq, flags;
|
|
struct xen_netif_rx_response *resp;
|
|
struct sk_buff_head rxq;
|
|
struct sk_buff *skb;
|
|
LIST_HEAD(notify);
|
|
int ret;
|
|
int nr_frags;
|
|
int count;
|
|
unsigned long offset;
|
|
struct skb_cb_overlay *sco;
|
|
|
|
struct netrx_pending_operations npo = {
|
|
.copy = netbk->grant_copy_op,
|
|
.meta = netbk->meta,
|
|
};
|
|
|
|
skb_queue_head_init(&rxq);
|
|
|
|
count = 0;
|
|
|
|
while ((skb = skb_dequeue(&netbk->rx_queue)) != NULL) {
|
|
vif = netdev_priv(skb->dev);
|
|
nr_frags = skb_shinfo(skb)->nr_frags;
|
|
|
|
sco = (struct skb_cb_overlay *)skb->cb;
|
|
sco->meta_slots_used = netbk_gop_skb(skb, &npo);
|
|
|
|
count += nr_frags + 1;
|
|
|
|
__skb_queue_tail(&rxq, skb);
|
|
|
|
/* Filled the batch queue? */
|
|
if (count + MAX_SKB_FRAGS >= XEN_NETIF_RX_RING_SIZE)
|
|
break;
|
|
}
|
|
|
|
BUG_ON(npo.meta_prod > ARRAY_SIZE(netbk->meta));
|
|
|
|
if (!npo.copy_prod)
|
|
return;
|
|
|
|
BUG_ON(npo.copy_prod > ARRAY_SIZE(netbk->grant_copy_op));
|
|
ret = HYPERVISOR_grant_table_op(GNTTABOP_copy, &netbk->grant_copy_op,
|
|
npo.copy_prod);
|
|
BUG_ON(ret != 0);
|
|
|
|
while ((skb = __skb_dequeue(&rxq)) != NULL) {
|
|
sco = (struct skb_cb_overlay *)skb->cb;
|
|
|
|
vif = netdev_priv(skb->dev);
|
|
|
|
if (netbk->meta[npo.meta_cons].gso_size && vif->gso_prefix) {
|
|
resp = RING_GET_RESPONSE(&vif->rx,
|
|
vif->rx.rsp_prod_pvt++);
|
|
|
|
resp->flags = XEN_NETRXF_gso_prefix | XEN_NETRXF_more_data;
|
|
|
|
resp->offset = netbk->meta[npo.meta_cons].gso_size;
|
|
resp->id = netbk->meta[npo.meta_cons].id;
|
|
resp->status = sco->meta_slots_used;
|
|
|
|
npo.meta_cons++;
|
|
sco->meta_slots_used--;
|
|
}
|
|
|
|
|
|
vif->dev->stats.tx_bytes += skb->len;
|
|
vif->dev->stats.tx_packets++;
|
|
|
|
status = netbk_check_gop(vif, sco->meta_slots_used, &npo);
|
|
|
|
if (sco->meta_slots_used == 1)
|
|
flags = 0;
|
|
else
|
|
flags = XEN_NETRXF_more_data;
|
|
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL) /* local packet? */
|
|
flags |= XEN_NETRXF_csum_blank | XEN_NETRXF_data_validated;
|
|
else if (skb->ip_summed == CHECKSUM_UNNECESSARY)
|
|
/* remote but checksummed. */
|
|
flags |= XEN_NETRXF_data_validated;
|
|
|
|
offset = 0;
|
|
resp = make_rx_response(vif, netbk->meta[npo.meta_cons].id,
|
|
status, offset,
|
|
netbk->meta[npo.meta_cons].size,
|
|
flags);
|
|
|
|
if (netbk->meta[npo.meta_cons].gso_size && !vif->gso_prefix) {
|
|
struct xen_netif_extra_info *gso =
|
|
(struct xen_netif_extra_info *)
|
|
RING_GET_RESPONSE(&vif->rx,
|
|
vif->rx.rsp_prod_pvt++);
|
|
|
|
resp->flags |= XEN_NETRXF_extra_info;
|
|
|
|
gso->u.gso.size = netbk->meta[npo.meta_cons].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;
|
|
}
|
|
|
|
netbk_add_frag_responses(vif, status,
|
|
netbk->meta + npo.meta_cons + 1,
|
|
sco->meta_slots_used);
|
|
|
|
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->rx, ret);
|
|
irq = vif->irq;
|
|
if (ret && list_empty(&vif->notify_list))
|
|
list_add_tail(&vif->notify_list, ¬ify);
|
|
|
|
xenvif_notify_tx_completion(vif);
|
|
|
|
xenvif_put(vif);
|
|
npo.meta_cons += sco->meta_slots_used;
|
|
dev_kfree_skb(skb);
|
|
}
|
|
|
|
list_for_each_entry_safe(vif, tmp, ¬ify, notify_list) {
|
|
notify_remote_via_irq(vif->irq);
|
|
list_del_init(&vif->notify_list);
|
|
}
|
|
|
|
/* More work to do? */
|
|
if (!skb_queue_empty(&netbk->rx_queue) &&
|
|
!timer_pending(&netbk->net_timer))
|
|
xen_netbk_kick_thread(netbk);
|
|
}
|
|
|
|
void xen_netbk_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb)
|
|
{
|
|
struct xen_netbk *netbk = vif->netbk;
|
|
|
|
skb_queue_tail(&netbk->rx_queue, skb);
|
|
|
|
xen_netbk_kick_thread(netbk);
|
|
}
|
|
|
|
static void xen_netbk_alarm(unsigned long data)
|
|
{
|
|
struct xen_netbk *netbk = (struct xen_netbk *)data;
|
|
xen_netbk_kick_thread(netbk);
|
|
}
|
|
|
|
static int __on_net_schedule_list(struct xenvif *vif)
|
|
{
|
|
return !list_empty(&vif->schedule_list);
|
|
}
|
|
|
|
/* Must be called with net_schedule_list_lock held */
|
|
static void remove_from_net_schedule_list(struct xenvif *vif)
|
|
{
|
|
if (likely(__on_net_schedule_list(vif))) {
|
|
list_del_init(&vif->schedule_list);
|
|
xenvif_put(vif);
|
|
}
|
|
}
|
|
|
|
static struct xenvif *poll_net_schedule_list(struct xen_netbk *netbk)
|
|
{
|
|
struct xenvif *vif = NULL;
|
|
|
|
spin_lock_irq(&netbk->net_schedule_list_lock);
|
|
if (list_empty(&netbk->net_schedule_list))
|
|
goto out;
|
|
|
|
vif = list_first_entry(&netbk->net_schedule_list,
|
|
struct xenvif, schedule_list);
|
|
if (!vif)
|
|
goto out;
|
|
|
|
xenvif_get(vif);
|
|
|
|
remove_from_net_schedule_list(vif);
|
|
out:
|
|
spin_unlock_irq(&netbk->net_schedule_list_lock);
|
|
return vif;
|
|
}
|
|
|
|
void xen_netbk_schedule_xenvif(struct xenvif *vif)
|
|
{
|
|
unsigned long flags;
|
|
struct xen_netbk *netbk = vif->netbk;
|
|
|
|
if (__on_net_schedule_list(vif))
|
|
goto kick;
|
|
|
|
spin_lock_irqsave(&netbk->net_schedule_list_lock, flags);
|
|
if (!__on_net_schedule_list(vif) &&
|
|
likely(xenvif_schedulable(vif))) {
|
|
list_add_tail(&vif->schedule_list, &netbk->net_schedule_list);
|
|
xenvif_get(vif);
|
|
}
|
|
spin_unlock_irqrestore(&netbk->net_schedule_list_lock, flags);
|
|
|
|
kick:
|
|
smp_mb();
|
|
if ((nr_pending_reqs(netbk) < (MAX_PENDING_REQS/2)) &&
|
|
!list_empty(&netbk->net_schedule_list))
|
|
xen_netbk_kick_thread(netbk);
|
|
}
|
|
|
|
void xen_netbk_deschedule_xenvif(struct xenvif *vif)
|
|
{
|
|
struct xen_netbk *netbk = vif->netbk;
|
|
spin_lock_irq(&netbk->net_schedule_list_lock);
|
|
remove_from_net_schedule_list(vif);
|
|
spin_unlock_irq(&netbk->net_schedule_list_lock);
|
|
}
|
|
|
|
void xen_netbk_check_rx_xenvif(struct xenvif *vif)
|
|
{
|
|
int more_to_do;
|
|
|
|
RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, more_to_do);
|
|
|
|
if (more_to_do)
|
|
xen_netbk_schedule_xenvif(vif);
|
|
}
|
|
|
|
static void tx_add_credit(struct xenvif *vif)
|
|
{
|
|
unsigned long max_burst, max_credit;
|
|
|
|
/*
|
|
* Allow a burst big enough to transmit a jumbo packet of up to 128kB.
|
|
* Otherwise the interface can seize up due to insufficient credit.
|
|
*/
|
|
max_burst = RING_GET_REQUEST(&vif->tx, vif->tx.req_cons)->size;
|
|
max_burst = min(max_burst, 131072UL);
|
|
max_burst = max(max_burst, vif->credit_bytes);
|
|
|
|
/* Take care that adding a new chunk of credit doesn't wrap to zero. */
|
|
max_credit = vif->remaining_credit + vif->credit_bytes;
|
|
if (max_credit < vif->remaining_credit)
|
|
max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */
|
|
|
|
vif->remaining_credit = min(max_credit, max_burst);
|
|
}
|
|
|
|
static void tx_credit_callback(unsigned long data)
|
|
{
|
|
struct xenvif *vif = (struct xenvif *)data;
|
|
tx_add_credit(vif);
|
|
xen_netbk_check_rx_xenvif(vif);
|
|
}
|
|
|
|
static void netbk_tx_err(struct xenvif *vif,
|
|
struct xen_netif_tx_request *txp, RING_IDX end)
|
|
{
|
|
RING_IDX cons = vif->tx.req_cons;
|
|
|
|
do {
|
|
make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR);
|
|
if (cons >= end)
|
|
break;
|
|
txp = RING_GET_REQUEST(&vif->tx, cons++);
|
|
} while (1);
|
|
vif->tx.req_cons = cons;
|
|
xen_netbk_check_rx_xenvif(vif);
|
|
xenvif_put(vif);
|
|
}
|
|
|
|
static int netbk_count_requests(struct xenvif *vif,
|
|
struct xen_netif_tx_request *first,
|
|
struct xen_netif_tx_request *txp,
|
|
int work_to_do)
|
|
{
|
|
RING_IDX cons = vif->tx.req_cons;
|
|
int frags = 0;
|
|
|
|
if (!(first->flags & XEN_NETTXF_more_data))
|
|
return 0;
|
|
|
|
do {
|
|
if (frags >= work_to_do) {
|
|
netdev_dbg(vif->dev, "Need more frags\n");
|
|
return -frags;
|
|
}
|
|
|
|
if (unlikely(frags >= MAX_SKB_FRAGS)) {
|
|
netdev_dbg(vif->dev, "Too many frags\n");
|
|
return -frags;
|
|
}
|
|
|
|
memcpy(txp, RING_GET_REQUEST(&vif->tx, cons + frags),
|
|
sizeof(*txp));
|
|
if (txp->size > first->size) {
|
|
netdev_dbg(vif->dev, "Frags galore\n");
|
|
return -frags;
|
|
}
|
|
|
|
first->size -= txp->size;
|
|
frags++;
|
|
|
|
if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) {
|
|
netdev_dbg(vif->dev, "txp->offset: %x, size: %u\n",
|
|
txp->offset, txp->size);
|
|
return -frags;
|
|
}
|
|
} while ((txp++)->flags & XEN_NETTXF_more_data);
|
|
return frags;
|
|
}
|
|
|
|
static struct page *xen_netbk_alloc_page(struct xen_netbk *netbk,
|
|
struct sk_buff *skb,
|
|
u16 pending_idx)
|
|
{
|
|
struct page *page;
|
|
page = alloc_page(GFP_KERNEL|__GFP_COLD);
|
|
if (!page)
|
|
return NULL;
|
|
set_page_ext(page, netbk, pending_idx);
|
|
netbk->mmap_pages[pending_idx] = page;
|
|
return page;
|
|
}
|
|
|
|
static struct gnttab_copy *xen_netbk_get_requests(struct xen_netbk *netbk,
|
|
struct xenvif *vif,
|
|
struct sk_buff *skb,
|
|
struct xen_netif_tx_request *txp,
|
|
struct gnttab_copy *gop)
|
|
{
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
skb_frag_t *frags = shinfo->frags;
|
|
u16 pending_idx = *((u16 *)skb->data);
|
|
int i, start;
|
|
|
|
/* Skip first skb fragment if it is on same page as header fragment. */
|
|
start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
|
|
|
|
for (i = start; i < shinfo->nr_frags; i++, txp++) {
|
|
struct page *page;
|
|
pending_ring_idx_t index;
|
|
struct pending_tx_info *pending_tx_info =
|
|
netbk->pending_tx_info;
|
|
|
|
index = pending_index(netbk->pending_cons++);
|
|
pending_idx = netbk->pending_ring[index];
|
|
page = xen_netbk_alloc_page(netbk, skb, pending_idx);
|
|
if (!page)
|
|
return NULL;
|
|
|
|
netbk->mmap_pages[pending_idx] = page;
|
|
|
|
gop->source.u.ref = txp->gref;
|
|
gop->source.domid = vif->domid;
|
|
gop->source.offset = txp->offset;
|
|
|
|
gop->dest.u.gmfn = virt_to_mfn(page_address(page));
|
|
gop->dest.domid = DOMID_SELF;
|
|
gop->dest.offset = txp->offset;
|
|
|
|
gop->len = txp->size;
|
|
gop->flags = GNTCOPY_source_gref;
|
|
|
|
gop++;
|
|
|
|
memcpy(&pending_tx_info[pending_idx].req, txp, sizeof(*txp));
|
|
xenvif_get(vif);
|
|
pending_tx_info[pending_idx].vif = vif;
|
|
frag_set_pending_idx(&frags[i], pending_idx);
|
|
}
|
|
|
|
return gop;
|
|
}
|
|
|
|
static int xen_netbk_tx_check_gop(struct xen_netbk *netbk,
|
|
struct sk_buff *skb,
|
|
struct gnttab_copy **gopp)
|
|
{
|
|
struct gnttab_copy *gop = *gopp;
|
|
u16 pending_idx = *((u16 *)skb->data);
|
|
struct pending_tx_info *pending_tx_info = netbk->pending_tx_info;
|
|
struct xenvif *vif = pending_tx_info[pending_idx].vif;
|
|
struct xen_netif_tx_request *txp;
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
int nr_frags = shinfo->nr_frags;
|
|
int i, err, start;
|
|
|
|
/* Check status of header. */
|
|
err = gop->status;
|
|
if (unlikely(err)) {
|
|
pending_ring_idx_t index;
|
|
index = pending_index(netbk->pending_prod++);
|
|
txp = &pending_tx_info[pending_idx].req;
|
|
make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR);
|
|
netbk->pending_ring[index] = pending_idx;
|
|
xenvif_put(vif);
|
|
}
|
|
|
|
/* Skip first skb fragment if it is on same page as header fragment. */
|
|
start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
|
|
|
|
for (i = start; i < nr_frags; i++) {
|
|
int j, newerr;
|
|
pending_ring_idx_t index;
|
|
|
|
pending_idx = frag_get_pending_idx(&shinfo->frags[i]);
|
|
|
|
/* Check error status: if okay then remember grant handle. */
|
|
newerr = (++gop)->status;
|
|
if (likely(!newerr)) {
|
|
/* Had a previous error? Invalidate this fragment. */
|
|
if (unlikely(err))
|
|
xen_netbk_idx_release(netbk, pending_idx);
|
|
continue;
|
|
}
|
|
|
|
/* Error on this fragment: respond to client with an error. */
|
|
txp = &netbk->pending_tx_info[pending_idx].req;
|
|
make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR);
|
|
index = pending_index(netbk->pending_prod++);
|
|
netbk->pending_ring[index] = pending_idx;
|
|
xenvif_put(vif);
|
|
|
|
/* Not the first error? Preceding frags already invalidated. */
|
|
if (err)
|
|
continue;
|
|
|
|
/* First error: invalidate header and preceding fragments. */
|
|
pending_idx = *((u16 *)skb->data);
|
|
xen_netbk_idx_release(netbk, pending_idx);
|
|
for (j = start; j < i; j++) {
|
|
pending_idx = frag_get_pending_idx(&shinfo->frags[i]);
|
|
xen_netbk_idx_release(netbk, pending_idx);
|
|
}
|
|
|
|
/* Remember the error: invalidate all subsequent fragments. */
|
|
err = newerr;
|
|
}
|
|
|
|
*gopp = gop + 1;
|
|
return err;
|
|
}
|
|
|
|
static void xen_netbk_fill_frags(struct xen_netbk *netbk, struct sk_buff *skb)
|
|
{
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
int nr_frags = shinfo->nr_frags;
|
|
int i;
|
|
|
|
for (i = 0; i < nr_frags; i++) {
|
|
skb_frag_t *frag = shinfo->frags + i;
|
|
struct xen_netif_tx_request *txp;
|
|
struct page *page;
|
|
u16 pending_idx;
|
|
|
|
pending_idx = frag_get_pending_idx(frag);
|
|
|
|
txp = &netbk->pending_tx_info[pending_idx].req;
|
|
page = virt_to_page(idx_to_kaddr(netbk, pending_idx));
|
|
__skb_fill_page_desc(skb, i, page, txp->offset, txp->size);
|
|
skb->len += txp->size;
|
|
skb->data_len += txp->size;
|
|
skb->truesize += txp->size;
|
|
|
|
/* Take an extra reference to offset xen_netbk_idx_release */
|
|
get_page(netbk->mmap_pages[pending_idx]);
|
|
xen_netbk_idx_release(netbk, pending_idx);
|
|
}
|
|
}
|
|
|
|
static int xen_netbk_get_extras(struct xenvif *vif,
|
|
struct xen_netif_extra_info *extras,
|
|
int work_to_do)
|
|
{
|
|
struct xen_netif_extra_info extra;
|
|
RING_IDX cons = vif->tx.req_cons;
|
|
|
|
do {
|
|
if (unlikely(work_to_do-- <= 0)) {
|
|
netdev_dbg(vif->dev, "Missing extra info\n");
|
|
return -EBADR;
|
|
}
|
|
|
|
memcpy(&extra, RING_GET_REQUEST(&vif->tx, cons),
|
|
sizeof(extra));
|
|
if (unlikely(!extra.type ||
|
|
extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
|
|
vif->tx.req_cons = ++cons;
|
|
netdev_dbg(vif->dev,
|
|
"Invalid extra type: %d\n", extra.type);
|
|
return -EINVAL;
|
|
}
|
|
|
|
memcpy(&extras[extra.type - 1], &extra, sizeof(extra));
|
|
vif->tx.req_cons = ++cons;
|
|
} while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE);
|
|
|
|
return work_to_do;
|
|
}
|
|
|
|
static int netbk_set_skb_gso(struct xenvif *vif,
|
|
struct sk_buff *skb,
|
|
struct xen_netif_extra_info *gso)
|
|
{
|
|
if (!gso->u.gso.size) {
|
|
netdev_dbg(vif->dev, "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) {
|
|
netdev_dbg(vif->dev, "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 int checksum_setup(struct xenvif *vif, struct sk_buff *skb)
|
|
{
|
|
struct iphdr *iph;
|
|
unsigned char *th;
|
|
int err = -EPROTO;
|
|
int recalculate_partial_csum = 0;
|
|
|
|
/*
|
|
* 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)) {
|
|
vif->rx_gso_checksum_fixup++;
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
recalculate_partial_csum = 1;
|
|
}
|
|
|
|
/* A non-CHECKSUM_PARTIAL SKB does not require setup. */
|
|
if (skb->ip_summed != CHECKSUM_PARTIAL)
|
|
return 0;
|
|
|
|
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);
|
|
|
|
if (recalculate_partial_csum) {
|
|
struct tcphdr *tcph = (struct tcphdr *)th;
|
|
tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
|
|
skb->len - iph->ihl*4,
|
|
IPPROTO_TCP, 0);
|
|
}
|
|
break;
|
|
case IPPROTO_UDP:
|
|
skb->csum_offset = offsetof(struct udphdr, check);
|
|
|
|
if (recalculate_partial_csum) {
|
|
struct udphdr *udph = (struct udphdr *)th;
|
|
udph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
|
|
skb->len - iph->ihl*4,
|
|
IPPROTO_UDP, 0);
|
|
}
|
|
break;
|
|
default:
|
|
if (net_ratelimit())
|
|
netdev_err(vif->dev,
|
|
"Attempting to checksum a non-TCP/UDP packet, dropping a protocol %d packet\n",
|
|
iph->protocol);
|
|
goto out;
|
|
}
|
|
|
|
if ((th + skb->csum_offset + 2) > skb_tail_pointer(skb))
|
|
goto out;
|
|
|
|
err = 0;
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static bool tx_credit_exceeded(struct xenvif *vif, unsigned size)
|
|
{
|
|
unsigned long now = jiffies;
|
|
unsigned long next_credit =
|
|
vif->credit_timeout.expires +
|
|
msecs_to_jiffies(vif->credit_usec / 1000);
|
|
|
|
/* Timer could already be pending in rare cases. */
|
|
if (timer_pending(&vif->credit_timeout))
|
|
return true;
|
|
|
|
/* Passed the point where we can replenish credit? */
|
|
if (time_after_eq(now, next_credit)) {
|
|
vif->credit_timeout.expires = now;
|
|
tx_add_credit(vif);
|
|
}
|
|
|
|
/* Still too big to send right now? Set a callback. */
|
|
if (size > vif->remaining_credit) {
|
|
vif->credit_timeout.data =
|
|
(unsigned long)vif;
|
|
vif->credit_timeout.function =
|
|
tx_credit_callback;
|
|
mod_timer(&vif->credit_timeout,
|
|
next_credit);
|
|
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static unsigned xen_netbk_tx_build_gops(struct xen_netbk *netbk)
|
|
{
|
|
struct gnttab_copy *gop = netbk->tx_copy_ops, *request_gop;
|
|
struct sk_buff *skb;
|
|
int ret;
|
|
|
|
while (((nr_pending_reqs(netbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) &&
|
|
!list_empty(&netbk->net_schedule_list)) {
|
|
struct xenvif *vif;
|
|
struct xen_netif_tx_request txreq;
|
|
struct xen_netif_tx_request txfrags[MAX_SKB_FRAGS];
|
|
struct page *page;
|
|
struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX-1];
|
|
u16 pending_idx;
|
|
RING_IDX idx;
|
|
int work_to_do;
|
|
unsigned int data_len;
|
|
pending_ring_idx_t index;
|
|
|
|
/* Get a netif from the list with work to do. */
|
|
vif = poll_net_schedule_list(netbk);
|
|
if (!vif)
|
|
continue;
|
|
|
|
RING_FINAL_CHECK_FOR_REQUESTS(&vif->tx, work_to_do);
|
|
if (!work_to_do) {
|
|
xenvif_put(vif);
|
|
continue;
|
|
}
|
|
|
|
idx = vif->tx.req_cons;
|
|
rmb(); /* Ensure that we see the request before we copy it. */
|
|
memcpy(&txreq, RING_GET_REQUEST(&vif->tx, idx), sizeof(txreq));
|
|
|
|
/* Credit-based scheduling. */
|
|
if (txreq.size > vif->remaining_credit &&
|
|
tx_credit_exceeded(vif, txreq.size)) {
|
|
xenvif_put(vif);
|
|
continue;
|
|
}
|
|
|
|
vif->remaining_credit -= txreq.size;
|
|
|
|
work_to_do--;
|
|
vif->tx.req_cons = ++idx;
|
|
|
|
memset(extras, 0, sizeof(extras));
|
|
if (txreq.flags & XEN_NETTXF_extra_info) {
|
|
work_to_do = xen_netbk_get_extras(vif, extras,
|
|
work_to_do);
|
|
idx = vif->tx.req_cons;
|
|
if (unlikely(work_to_do < 0)) {
|
|
netbk_tx_err(vif, &txreq, idx);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
ret = netbk_count_requests(vif, &txreq, txfrags, work_to_do);
|
|
if (unlikely(ret < 0)) {
|
|
netbk_tx_err(vif, &txreq, idx - ret);
|
|
continue;
|
|
}
|
|
idx += ret;
|
|
|
|
if (unlikely(txreq.size < ETH_HLEN)) {
|
|
netdev_dbg(vif->dev,
|
|
"Bad packet size: %d\n", txreq.size);
|
|
netbk_tx_err(vif, &txreq, idx);
|
|
continue;
|
|
}
|
|
|
|
/* No crossing a page as the payload mustn't fragment. */
|
|
if (unlikely((txreq.offset + txreq.size) > PAGE_SIZE)) {
|
|
netdev_dbg(vif->dev,
|
|
"txreq.offset: %x, size: %u, end: %lu\n",
|
|
txreq.offset, txreq.size,
|
|
(txreq.offset&~PAGE_MASK) + txreq.size);
|
|
netbk_tx_err(vif, &txreq, idx);
|
|
continue;
|
|
}
|
|
|
|
index = pending_index(netbk->pending_cons);
|
|
pending_idx = netbk->pending_ring[index];
|
|
|
|
data_len = (txreq.size > PKT_PROT_LEN &&
|
|
ret < MAX_SKB_FRAGS) ?
|
|
PKT_PROT_LEN : txreq.size;
|
|
|
|
skb = alloc_skb(data_len + NET_SKB_PAD + NET_IP_ALIGN,
|
|
GFP_ATOMIC | __GFP_NOWARN);
|
|
if (unlikely(skb == NULL)) {
|
|
netdev_dbg(vif->dev,
|
|
"Can't allocate a skb in start_xmit.\n");
|
|
netbk_tx_err(vif, &txreq, idx);
|
|
break;
|
|
}
|
|
|
|
/* Packets passed to netif_rx() must have some headroom. */
|
|
skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
|
|
|
|
if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) {
|
|
struct xen_netif_extra_info *gso;
|
|
gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1];
|
|
|
|
if (netbk_set_skb_gso(vif, skb, gso)) {
|
|
kfree_skb(skb);
|
|
netbk_tx_err(vif, &txreq, idx);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
/* XXX could copy straight to head */
|
|
page = xen_netbk_alloc_page(netbk, skb, pending_idx);
|
|
if (!page) {
|
|
kfree_skb(skb);
|
|
netbk_tx_err(vif, &txreq, idx);
|
|
continue;
|
|
}
|
|
|
|
netbk->mmap_pages[pending_idx] = page;
|
|
|
|
gop->source.u.ref = txreq.gref;
|
|
gop->source.domid = vif->domid;
|
|
gop->source.offset = txreq.offset;
|
|
|
|
gop->dest.u.gmfn = virt_to_mfn(page_address(page));
|
|
gop->dest.domid = DOMID_SELF;
|
|
gop->dest.offset = txreq.offset;
|
|
|
|
gop->len = txreq.size;
|
|
gop->flags = GNTCOPY_source_gref;
|
|
|
|
gop++;
|
|
|
|
memcpy(&netbk->pending_tx_info[pending_idx].req,
|
|
&txreq, sizeof(txreq));
|
|
netbk->pending_tx_info[pending_idx].vif = vif;
|
|
*((u16 *)skb->data) = pending_idx;
|
|
|
|
__skb_put(skb, data_len);
|
|
|
|
skb_shinfo(skb)->nr_frags = ret;
|
|
if (data_len < txreq.size) {
|
|
skb_shinfo(skb)->nr_frags++;
|
|
frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
|
|
pending_idx);
|
|
} else {
|
|
frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
|
|
INVALID_PENDING_IDX);
|
|
}
|
|
|
|
__skb_queue_tail(&netbk->tx_queue, skb);
|
|
|
|
netbk->pending_cons++;
|
|
|
|
request_gop = xen_netbk_get_requests(netbk, vif,
|
|
skb, txfrags, gop);
|
|
if (request_gop == NULL) {
|
|
kfree_skb(skb);
|
|
netbk_tx_err(vif, &txreq, idx);
|
|
continue;
|
|
}
|
|
gop = request_gop;
|
|
|
|
vif->tx.req_cons = idx;
|
|
xen_netbk_check_rx_xenvif(vif);
|
|
|
|
if ((gop-netbk->tx_copy_ops) >= ARRAY_SIZE(netbk->tx_copy_ops))
|
|
break;
|
|
}
|
|
|
|
return gop - netbk->tx_copy_ops;
|
|
}
|
|
|
|
static void xen_netbk_tx_submit(struct xen_netbk *netbk)
|
|
{
|
|
struct gnttab_copy *gop = netbk->tx_copy_ops;
|
|
struct sk_buff *skb;
|
|
|
|
while ((skb = __skb_dequeue(&netbk->tx_queue)) != NULL) {
|
|
struct xen_netif_tx_request *txp;
|
|
struct xenvif *vif;
|
|
u16 pending_idx;
|
|
unsigned data_len;
|
|
|
|
pending_idx = *((u16 *)skb->data);
|
|
vif = netbk->pending_tx_info[pending_idx].vif;
|
|
txp = &netbk->pending_tx_info[pending_idx].req;
|
|
|
|
/* Check the remap error code. */
|
|
if (unlikely(xen_netbk_tx_check_gop(netbk, skb, &gop))) {
|
|
netdev_dbg(vif->dev, "netback grant failed.\n");
|
|
skb_shinfo(skb)->nr_frags = 0;
|
|
kfree_skb(skb);
|
|
continue;
|
|
}
|
|
|
|
data_len = skb->len;
|
|
memcpy(skb->data,
|
|
(void *)(idx_to_kaddr(netbk, pending_idx)|txp->offset),
|
|
data_len);
|
|
if (data_len < txp->size) {
|
|
/* Append the packet payload as a fragment. */
|
|
txp->offset += data_len;
|
|
txp->size -= data_len;
|
|
} else {
|
|
/* Schedule a response immediately. */
|
|
xen_netbk_idx_release(netbk, pending_idx);
|
|
}
|
|
|
|
if (txp->flags & XEN_NETTXF_csum_blank)
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
else if (txp->flags & XEN_NETTXF_data_validated)
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
xen_netbk_fill_frags(netbk, skb);
|
|
|
|
/*
|
|
* If the initial fragment was < PKT_PROT_LEN then
|
|
* pull through some bytes from the other fragments to
|
|
* increase the linear region to PKT_PROT_LEN bytes.
|
|
*/
|
|
if (skb_headlen(skb) < PKT_PROT_LEN && skb_is_nonlinear(skb)) {
|
|
int target = min_t(int, skb->len, PKT_PROT_LEN);
|
|
__pskb_pull_tail(skb, target - skb_headlen(skb));
|
|
}
|
|
|
|
skb->dev = vif->dev;
|
|
skb->protocol = eth_type_trans(skb, skb->dev);
|
|
|
|
if (checksum_setup(vif, skb)) {
|
|
netdev_dbg(vif->dev,
|
|
"Can't setup checksum in net_tx_action\n");
|
|
kfree_skb(skb);
|
|
continue;
|
|
}
|
|
|
|
vif->dev->stats.rx_bytes += skb->len;
|
|
vif->dev->stats.rx_packets++;
|
|
|
|
xenvif_receive_skb(vif, skb);
|
|
}
|
|
}
|
|
|
|
/* Called after netfront has transmitted */
|
|
static void xen_netbk_tx_action(struct xen_netbk *netbk)
|
|
{
|
|
unsigned nr_gops;
|
|
int ret;
|
|
|
|
nr_gops = xen_netbk_tx_build_gops(netbk);
|
|
|
|
if (nr_gops == 0)
|
|
return;
|
|
ret = HYPERVISOR_grant_table_op(GNTTABOP_copy,
|
|
netbk->tx_copy_ops, nr_gops);
|
|
BUG_ON(ret);
|
|
|
|
xen_netbk_tx_submit(netbk);
|
|
|
|
}
|
|
|
|
static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx)
|
|
{
|
|
struct xenvif *vif;
|
|
struct pending_tx_info *pending_tx_info;
|
|
pending_ring_idx_t index;
|
|
|
|
/* Already complete? */
|
|
if (netbk->mmap_pages[pending_idx] == NULL)
|
|
return;
|
|
|
|
pending_tx_info = &netbk->pending_tx_info[pending_idx];
|
|
|
|
vif = pending_tx_info->vif;
|
|
|
|
make_tx_response(vif, &pending_tx_info->req, XEN_NETIF_RSP_OKAY);
|
|
|
|
index = pending_index(netbk->pending_prod++);
|
|
netbk->pending_ring[index] = pending_idx;
|
|
|
|
xenvif_put(vif);
|
|
|
|
netbk->mmap_pages[pending_idx]->mapping = 0;
|
|
put_page(netbk->mmap_pages[pending_idx]);
|
|
netbk->mmap_pages[pending_idx] = NULL;
|
|
}
|
|
|
|
static void make_tx_response(struct xenvif *vif,
|
|
struct xen_netif_tx_request *txp,
|
|
s8 st)
|
|
{
|
|
RING_IDX i = vif->tx.rsp_prod_pvt;
|
|
struct xen_netif_tx_response *resp;
|
|
int notify;
|
|
|
|
resp = RING_GET_RESPONSE(&vif->tx, i);
|
|
resp->id = txp->id;
|
|
resp->status = st;
|
|
|
|
if (txp->flags & XEN_NETTXF_extra_info)
|
|
RING_GET_RESPONSE(&vif->tx, ++i)->status = XEN_NETIF_RSP_NULL;
|
|
|
|
vif->tx.rsp_prod_pvt = ++i;
|
|
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&vif->tx, notify);
|
|
if (notify)
|
|
notify_remote_via_irq(vif->irq);
|
|
}
|
|
|
|
static struct xen_netif_rx_response *make_rx_response(struct xenvif *vif,
|
|
u16 id,
|
|
s8 st,
|
|
u16 offset,
|
|
u16 size,
|
|
u16 flags)
|
|
{
|
|
RING_IDX i = vif->rx.rsp_prod_pvt;
|
|
struct xen_netif_rx_response *resp;
|
|
|
|
resp = RING_GET_RESPONSE(&vif->rx, i);
|
|
resp->offset = offset;
|
|
resp->flags = flags;
|
|
resp->id = id;
|
|
resp->status = (s16)size;
|
|
if (st < 0)
|
|
resp->status = (s16)st;
|
|
|
|
vif->rx.rsp_prod_pvt = ++i;
|
|
|
|
return resp;
|
|
}
|
|
|
|
static inline int rx_work_todo(struct xen_netbk *netbk)
|
|
{
|
|
return !skb_queue_empty(&netbk->rx_queue);
|
|
}
|
|
|
|
static inline int tx_work_todo(struct xen_netbk *netbk)
|
|
{
|
|
|
|
if (((nr_pending_reqs(netbk) + MAX_SKB_FRAGS) < MAX_PENDING_REQS) &&
|
|
!list_empty(&netbk->net_schedule_list))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int xen_netbk_kthread(void *data)
|
|
{
|
|
struct xen_netbk *netbk = data;
|
|
while (!kthread_should_stop()) {
|
|
wait_event_interruptible(netbk->wq,
|
|
rx_work_todo(netbk) ||
|
|
tx_work_todo(netbk) ||
|
|
kthread_should_stop());
|
|
cond_resched();
|
|
|
|
if (kthread_should_stop())
|
|
break;
|
|
|
|
if (rx_work_todo(netbk))
|
|
xen_netbk_rx_action(netbk);
|
|
|
|
if (tx_work_todo(netbk))
|
|
xen_netbk_tx_action(netbk);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void xen_netbk_unmap_frontend_rings(struct xenvif *vif)
|
|
{
|
|
if (vif->tx.sring)
|
|
xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif),
|
|
vif->tx.sring);
|
|
if (vif->rx.sring)
|
|
xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(vif),
|
|
vif->rx.sring);
|
|
}
|
|
|
|
int xen_netbk_map_frontend_rings(struct xenvif *vif,
|
|
grant_ref_t tx_ring_ref,
|
|
grant_ref_t rx_ring_ref)
|
|
{
|
|
void *addr;
|
|
struct xen_netif_tx_sring *txs;
|
|
struct xen_netif_rx_sring *rxs;
|
|
|
|
int err = -ENOMEM;
|
|
|
|
err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif),
|
|
tx_ring_ref, &addr);
|
|
if (err)
|
|
goto err;
|
|
|
|
txs = (struct xen_netif_tx_sring *)addr;
|
|
BACK_RING_INIT(&vif->tx, txs, PAGE_SIZE);
|
|
|
|
err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(vif),
|
|
rx_ring_ref, &addr);
|
|
if (err)
|
|
goto err;
|
|
|
|
rxs = (struct xen_netif_rx_sring *)addr;
|
|
BACK_RING_INIT(&vif->rx, rxs, PAGE_SIZE);
|
|
|
|
vif->rx_req_cons_peek = 0;
|
|
|
|
return 0;
|
|
|
|
err:
|
|
xen_netbk_unmap_frontend_rings(vif);
|
|
return err;
|
|
}
|
|
|
|
static int __init netback_init(void)
|
|
{
|
|
int i;
|
|
int rc = 0;
|
|
int group;
|
|
|
|
if (!xen_pv_domain())
|
|
return -ENODEV;
|
|
|
|
xen_netbk_group_nr = num_online_cpus();
|
|
xen_netbk = vzalloc(sizeof(struct xen_netbk) * xen_netbk_group_nr);
|
|
if (!xen_netbk) {
|
|
printk(KERN_ALERT "%s: out of memory\n", __func__);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
for (group = 0; group < xen_netbk_group_nr; group++) {
|
|
struct xen_netbk *netbk = &xen_netbk[group];
|
|
skb_queue_head_init(&netbk->rx_queue);
|
|
skb_queue_head_init(&netbk->tx_queue);
|
|
|
|
init_timer(&netbk->net_timer);
|
|
netbk->net_timer.data = (unsigned long)netbk;
|
|
netbk->net_timer.function = xen_netbk_alarm;
|
|
|
|
netbk->pending_cons = 0;
|
|
netbk->pending_prod = MAX_PENDING_REQS;
|
|
for (i = 0; i < MAX_PENDING_REQS; i++)
|
|
netbk->pending_ring[i] = i;
|
|
|
|
init_waitqueue_head(&netbk->wq);
|
|
netbk->task = kthread_create(xen_netbk_kthread,
|
|
(void *)netbk,
|
|
"netback/%u", group);
|
|
|
|
if (IS_ERR(netbk->task)) {
|
|
printk(KERN_ALERT "kthread_run() fails at netback\n");
|
|
del_timer(&netbk->net_timer);
|
|
rc = PTR_ERR(netbk->task);
|
|
goto failed_init;
|
|
}
|
|
|
|
kthread_bind(netbk->task, group);
|
|
|
|
INIT_LIST_HEAD(&netbk->net_schedule_list);
|
|
|
|
spin_lock_init(&netbk->net_schedule_list_lock);
|
|
|
|
atomic_set(&netbk->netfront_count, 0);
|
|
|
|
wake_up_process(netbk->task);
|
|
}
|
|
|
|
rc = xenvif_xenbus_init();
|
|
if (rc)
|
|
goto failed_init;
|
|
|
|
return 0;
|
|
|
|
failed_init:
|
|
while (--group >= 0) {
|
|
struct xen_netbk *netbk = &xen_netbk[group];
|
|
for (i = 0; i < MAX_PENDING_REQS; i++) {
|
|
if (netbk->mmap_pages[i])
|
|
__free_page(netbk->mmap_pages[i]);
|
|
}
|
|
del_timer(&netbk->net_timer);
|
|
kthread_stop(netbk->task);
|
|
}
|
|
vfree(xen_netbk);
|
|
return rc;
|
|
|
|
}
|
|
|
|
module_init(netback_init);
|
|
|
|
MODULE_LICENSE("Dual BSD/GPL");
|
|
MODULE_ALIAS("xen-backend:vif");
|