drivers/net/xen-netback/common.h

   1 /*
   2  * This program is free software; you can redistribute it and/or
   3  * modify it under the terms of the GNU General Public License version 2
   4  * as published by the Free Software Foundation; or, when distributed
   5  * separately from the Linux kernel or incorporated into other
   6  * software packages, subject to the following license:
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this source file (the "Software"), to deal in the Software without
  10  * restriction, including without limitation the rights to use, copy, modify,
  11  * merge, publish, distribute, sublicense, and/or sell copies of the Software,
  12  * and to permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  24  * IN THE SOFTWARE.
  25  */
  26
  27 #ifndef __XEN_NETBACK__COMMON_H__
  28 #define __XEN_NETBACK__COMMON_H__
  29
  30 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
  31
  32 #include <linux/module.h>
  33 #include <linux/interrupt.h>
  34 #include <linux/slab.h>
  35 #include <linux/ip.h>
  36 #include <linux/in.h>
  37 #include <linux/io.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/etherdevice.h>
  40 #include <linux/wait.h>
  41 #include <linux/sched.h>
  42
  43 #include <xen/interface/io/netif.h>
  44 #include <xen/interface/grant_table.h>
  45 #include <xen/grant_table.h>
  46 #include <xen/xenbus.h>
  47
  48 struct xen_netbk;
  49
  50 struct xenvif {
  51         /* Unique identifier for this interface. */
  52         domid_t          domid;
  53         unsigned int     handle;
  54
  55         /* Reference to netback processing backend. */
  56         struct xen_netbk *netbk;
  57
  58         u8               fe_dev_addr[6];
  59
  60         /* Physical parameters of the comms window. */
  61         unsigned int     irq;
  62
  63         /* List of frontends to notify after a batch of frames sent. */
  64         struct list_head notify_list;
  65
  66         /* The shared rings and indexes. */
  67         struct xen_netif_tx_back_ring tx;
  68         struct xen_netif_rx_back_ring rx;
  69
  70         /* Frontend feature information. */
  71         u8 can_sg:1;
  72         u8 gso:1;
  73         u8 gso_prefix:1;
  74         u8 csum:1;
  75
  76         /* Internal feature information. */
  77         u8 can_queue:1;     /* can queue packets for receiver? */
  78
  79         /*
  80          * Allow xenvif_start_xmit() to peek ahead in the rx request
  81          * ring.  This is a prediction of what rx_req_cons will be
  82          * once all queued skbs are put on the ring.
  83          */
  84         RING_IDX rx_req_cons_peek;
  85
  86         /* Transmit shaping: allow 'credit_bytes' every 'credit_usec'. */
  87         unsigned long   credit_bytes;
  88         unsigned long   credit_usec;
  89         unsigned long   remaining_credit;
  90         struct timer_list credit_timeout;
  91
  92         /* Statistics */
  93         unsigned long rx_gso_checksum_fixup;
  94
  95         /* Miscellaneous private stuff. */
  96         struct list_head schedule_list;
  97         atomic_t         refcnt;
  98         struct net_device *dev;
  99
 100         wait_queue_head_t waiting_to_free;
 101 };
 102
 103 static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif)
 104 {
 105         return to_xenbus_device(vif->dev->dev.parent);
 106 }
 107
 108 #define XEN_NETIF_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE)
 109 #define XEN_NETIF_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE)
 110
 111 struct xenvif *xenvif_alloc(struct device *parent,
 112                             domid_t domid,
 113                             unsigned int handle);
 114
 115 int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
 116                    unsigned long rx_ring_ref, unsigned int evtchn);
 117 void xenvif_disconnect(struct xenvif *vif);
 118
 119 void xenvif_get(struct xenvif *vif);
 120 void xenvif_put(struct xenvif *vif);
 121
 122 int xenvif_xenbus_init(void);
 123
 124 int xenvif_schedulable(struct xenvif *vif);
 125
 126 int xen_netbk_rx_ring_full(struct xenvif *vif);
 127
 128 int xen_netbk_must_stop_queue(struct xenvif *vif);
 129
 130 /* (Un)Map communication rings. */
 131 void xen_netbk_unmap_frontend_rings(struct xenvif *vif);
 132 int xen_netbk_map_frontend_rings(struct xenvif *vif,
 133                                  grant_ref_t tx_ring_ref,
 134                                  grant_ref_t rx_ring_ref);
 135
 136 /* (De)Register a xenvif with the netback backend. */
 137 void xen_netbk_add_xenvif(struct xenvif *vif);
 138 void xen_netbk_remove_xenvif(struct xenvif *vif);
 139
 140 /* (De)Schedule backend processing for a xenvif */
 141 void xen_netbk_schedule_xenvif(struct xenvif *vif);
 142 void xen_netbk_deschedule_xenvif(struct xenvif *vif);
 143
 144 /* Check for SKBs from frontend and schedule backend processing */
 145 void xen_netbk_check_rx_xenvif(struct xenvif *vif);
 146 /* Receive an SKB from the frontend */
 147 void xenvif_receive_skb(struct xenvif *vif, struct sk_buff *skb);
 148
 149 /* Queue an SKB for transmission to the frontend */
 150 void xen_netbk_queue_tx_skb(struct xenvif *vif, struct sk_buff *skb);
 151 /* Notify xenvif that ring now has space to send an skb to the frontend */
 152 void xenvif_notify_tx_completion(struct xenvif *vif);
 153
 154 /* Prevent the device from generating any further traffic. */
 155 void xenvif_carrier_off(struct xenvif *vif);
 156
 157 /* Returns number of ring slots required to send an skb to the frontend */
 158 unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb);
 159
 160 #endif /* __XEN_NETBACK__COMMON_H__ */