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27 #ifndef __XEN_NETBACK__COMMON_H__
28 #define __XEN_NETBACK__COMMON_H__
30 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
32 #include <linux/module.h>
33 #include <linux/interrupt.h>
34 #include <linux/slab.h>
38 #include <linux/netdevice.h>
39 #include <linux/etherdevice.h>
40 #include <linux/wait.h>
41 #include <linux/sched.h>
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 #include <linux/debugfs.h>
49 typedef unsigned int pending_ring_idx_t;
50 #define INVALID_PENDING_RING_IDX (~0U)
52 struct pending_tx_info {
53 struct xen_netif_tx_request req; /* tx request */
54 /* Callback data for released SKBs. The callback is always
55 * xenvif_zerocopy_callback, desc contains the pending_idx, which is
56 * also an index in pending_tx_info array. It is initialized in
57 * xenvif_alloc and it never changes.
58 * skb_shinfo(skb)->destructor_arg points to the first mapped slot's
59 * callback_struct in this array of struct pending_tx_info's, then ctx
60 * to the next, or NULL if there is no more slot for this skb.
61 * ubuf_to_vif is a helper which finds the struct xenvif from a pointer
64 struct ubuf_info callback_struct;
67 #define XEN_NETIF_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE)
68 #define XEN_NETIF_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE)
70 struct xenvif_rx_meta {
77 #define GSO_BIT(type) \
78 (1 << XEN_NETIF_GSO_TYPE_ ## type)
80 /* Discriminate from any valid pending_idx value. */
81 #define INVALID_PENDING_IDX 0xFFFF
83 #define MAX_BUFFER_OFFSET PAGE_SIZE
85 #define MAX_PENDING_REQS XEN_NETIF_TX_RING_SIZE
87 /* It's possible for an skb to have a maximal number of frags
88 * but still be less than MAX_BUFFER_OFFSET in size. Thus the
89 * worst-case number of copy operations is MAX_SKB_FRAGS per
92 #define MAX_GRANT_COPY_OPS (MAX_SKB_FRAGS * XEN_NETIF_RX_RING_SIZE)
94 #define NETBACK_INVALID_HANDLE -1
96 /* To avoid confusion, we define XEN_NETBK_LEGACY_SLOTS_MAX indicating
97 * the maximum slots a valid packet can use. Now this value is defined
98 * to be XEN_NETIF_NR_SLOTS_MIN, which is supposed to be supported by
101 #define XEN_NETBK_LEGACY_SLOTS_MAX XEN_NETIF_NR_SLOTS_MIN
103 /* Queue name is interface name with "-qNNN" appended */
104 #define QUEUE_NAME_SIZE (IFNAMSIZ + 5)
106 /* IRQ name is queue name with "-tx" or "-rx" appended */
107 #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3)
111 struct xenvif_stats {
112 /* Stats fields to be updated per-queue.
113 * A subset of struct net_device_stats that contains only the
114 * fields that are updated in netback.c for each queue.
116 unsigned int rx_bytes;
117 unsigned int rx_packets;
118 unsigned int tx_bytes;
119 unsigned int tx_packets;
121 /* Additional stats used by xenvif */
122 unsigned long rx_gso_checksum_fixup;
123 unsigned long tx_zerocopy_sent;
124 unsigned long tx_zerocopy_success;
125 unsigned long tx_zerocopy_fail;
126 unsigned long tx_frag_overflow;
129 struct xenvif_queue { /* Per-queue data for xenvif */
130 unsigned int id; /* Queue ID, 0-based */
131 char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */
132 struct xenvif *vif; /* Parent VIF */
134 /* Use NAPI for guest TX */
135 struct napi_struct napi;
136 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */
138 /* Only used when feature-split-event-channels = 1 */
139 char tx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-tx */
140 struct xen_netif_tx_back_ring tx;
141 struct sk_buff_head tx_queue;
142 struct page *mmap_pages[MAX_PENDING_REQS];
143 pending_ring_idx_t pending_prod;
144 pending_ring_idx_t pending_cons;
145 u16 pending_ring[MAX_PENDING_REQS];
146 struct pending_tx_info pending_tx_info[MAX_PENDING_REQS];
147 grant_handle_t grant_tx_handle[MAX_PENDING_REQS];
149 struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS];
150 struct gnttab_map_grant_ref tx_map_ops[MAX_PENDING_REQS];
151 struct gnttab_unmap_grant_ref tx_unmap_ops[MAX_PENDING_REQS];
152 /* passed to gnttab_[un]map_refs with pages under (un)mapping */
153 struct page *pages_to_map[MAX_PENDING_REQS];
154 struct page *pages_to_unmap[MAX_PENDING_REQS];
156 /* This prevents zerocopy callbacks to race over dealloc_ring */
157 spinlock_t callback_lock;
158 /* This prevents dealloc thread and NAPI instance to race over response
159 * creation and pending_ring in xenvif_idx_release. In xenvif_tx_err
160 * it only protect response creation
162 spinlock_t response_lock;
163 pending_ring_idx_t dealloc_prod;
164 pending_ring_idx_t dealloc_cons;
165 u16 dealloc_ring[MAX_PENDING_REQS];
166 struct task_struct *dealloc_task;
167 wait_queue_head_t dealloc_wq;
168 atomic_t inflight_packets;
170 /* Use kthread for guest RX */
171 struct task_struct *task;
172 wait_queue_head_t wq;
173 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */
175 /* Only used when feature-split-event-channels = 1 */
176 char rx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */
177 struct xen_netif_rx_back_ring rx;
178 struct sk_buff_head rx_queue;
180 unsigned int rx_queue_max;
181 unsigned int rx_queue_len;
182 unsigned long last_rx_time;
185 struct gnttab_copy grant_copy_op[MAX_GRANT_COPY_OPS];
187 /* We create one meta structure per ring request we consume, so
188 * the maximum number is the same as the ring size.
190 struct xenvif_rx_meta meta[XEN_NETIF_RX_RING_SIZE];
192 /* Transmit shaping: allow 'credit_bytes' every 'credit_usec'. */
193 unsigned long credit_bytes;
194 unsigned long credit_usec;
195 unsigned long remaining_credit;
196 struct timer_list credit_timeout;
197 u64 credit_window_start;
200 struct xenvif_stats stats;
203 enum state_bit_shift {
204 /* This bit marks that the vif is connected */
205 VIF_STATUS_CONNECTED,
208 struct xenvif_mcast_addr {
209 struct list_head entry;
214 #define XEN_NETBK_MCAST_MAX 64
217 /* Unique identifier for this interface. */
222 struct list_head fe_mcast_addr;
223 unsigned int fe_mcast_count;
225 /* Frontend feature information. */
232 u8 multicast_control:1;
234 /* Is this interface disabled? True when backend discovers
238 unsigned long status;
239 unsigned long drain_timeout;
240 unsigned long stall_timeout;
243 struct xenvif_queue *queues;
244 unsigned int num_queues; /* active queues, resource allocated */
245 unsigned int stalled_queues;
247 struct xenbus_watch credit_watch;
251 #ifdef CONFIG_DEBUG_FS
252 struct dentry *xenvif_dbg_root;
255 /* Miscellaneous private stuff. */
256 struct net_device *dev;
259 struct xenvif_rx_cb {
260 unsigned long expires;
264 #define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb)
266 static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif)
268 return to_xenbus_device(vif->dev->dev.parent);
271 void xenvif_tx_credit_callback(unsigned long data);
273 struct xenvif *xenvif_alloc(struct device *parent,
275 unsigned int handle);
277 int xenvif_init_queue(struct xenvif_queue *queue);
278 void xenvif_deinit_queue(struct xenvif_queue *queue);
280 int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref,
281 unsigned long rx_ring_ref, unsigned int tx_evtchn,
282 unsigned int rx_evtchn);
283 void xenvif_disconnect(struct xenvif *vif);
284 void xenvif_free(struct xenvif *vif);
286 int xenvif_xenbus_init(void);
287 void xenvif_xenbus_fini(void);
289 int xenvif_schedulable(struct xenvif *vif);
291 int xenvif_queue_stopped(struct xenvif_queue *queue);
292 void xenvif_wake_queue(struct xenvif_queue *queue);
294 /* (Un)Map communication rings. */
295 void xenvif_unmap_frontend_rings(struct xenvif_queue *queue);
296 int xenvif_map_frontend_rings(struct xenvif_queue *queue,
297 grant_ref_t tx_ring_ref,
298 grant_ref_t rx_ring_ref);
300 /* Check for SKBs from frontend and schedule backend processing */
301 void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue);
303 /* Prevent the device from generating any further traffic. */
304 void xenvif_carrier_off(struct xenvif *vif);
306 int xenvif_tx_action(struct xenvif_queue *queue, int budget);
308 int xenvif_kthread_guest_rx(void *data);
309 void xenvif_kick_thread(struct xenvif_queue *queue);
311 int xenvif_dealloc_kthread(void *data);
313 void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb);
315 void xenvif_carrier_on(struct xenvif *vif);
317 /* Callback from stack when TX packet can be released */
318 void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success);
320 /* Unmap a pending page and release it back to the guest */
321 void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx);
323 static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue)
325 return MAX_PENDING_REQS -
326 queue->pending_prod + queue->pending_cons;
329 irqreturn_t xenvif_interrupt(int irq, void *dev_id);
331 extern bool separate_tx_rx_irq;
333 extern unsigned int rx_drain_timeout_msecs;
334 extern unsigned int rx_stall_timeout_msecs;
335 extern unsigned int xenvif_max_queues;
337 #ifdef CONFIG_DEBUG_FS
338 extern struct dentry *xen_netback_dbg_root;
341 void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue,
342 struct sk_buff *skb);
343 void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue);
345 /* Multicast control */
346 bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr);
347 void xenvif_mcast_addr_list_free(struct xenvif *vif);
349 #endif /* __XEN_NETBACK__COMMON_H__ */