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common.h
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1 /*
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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
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13  * the following conditions:
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15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
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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,
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21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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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>
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. */
53  unsigned int handle;
54 
55  /* Reference to netback processing backend. */
56  struct xen_netbk *netbk;
57 
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. */
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. */
72  u8 gso: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  */
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;
91 
92  /* Statistics */
93  unsigned long rx_gso_checksum_fixup;
94 
95  /* Miscellaneous private stuff. */
98  struct net_device *dev;
99 
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 /* Returns number of ring slots required to send an skb to the frontend */
155 unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb);
156 
157 #endif /* __XEN_NETBACK__COMMON_H__ */