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
48struct xen_netbk;
49
50struct 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
103static 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
111struct xenvif *xenvif_alloc(struct device *parent,
112			    domid_t domid,
113			    unsigned int handle);
114
115int xenvif_connect(struct xenvif *vif, unsigned long tx_ring_ref,
116		   unsigned long rx_ring_ref, unsigned int evtchn);
117void xenvif_disconnect(struct xenvif *vif);
118
119void xenvif_get(struct xenvif *vif);
120void xenvif_put(struct xenvif *vif);
121
122int xenvif_xenbus_init(void);
123
124int xenvif_schedulable(struct xenvif *vif);
125
126int xen_netbk_rx_ring_full(struct xenvif *vif);
127
128int xen_netbk_must_stop_queue(struct xenvif *vif);
129
130/* (Un)Map communication rings. */
131void xen_netbk_unmap_frontend_rings(struct xenvif *vif);
132int 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. */
137void xen_netbk_add_xenvif(struct xenvif *vif);
138void xen_netbk_remove_xenvif(struct xenvif *vif);
139
140/* (De)Schedule backend processing for a xenvif */
141void xen_netbk_schedule_xenvif(struct xenvif *vif);
142void xen_netbk_deschedule_xenvif(struct xenvif *vif);
143
144/* Check for SKBs from frontend and schedule backend processing */
145void xen_netbk_check_rx_xenvif(struct xenvif *vif);
146/* Receive an SKB from the frontend */
147void xenvif_receive_skb(struct xenvif *vif, struct sk_buff *skb);
148
149/* Queue an SKB for transmission to the frontend */
150void 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 */
152void xenvif_notify_tx_completion(struct xenvif *vif);
153
154/* Returns number of ring slots required to send an skb to the frontend */
155unsigned int xen_netbk_count_skb_slots(struct xenvif *vif, struct sk_buff *skb);
156
157#endif /* __XEN_NETBACK__COMMON_H__ */
158