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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>
48 #include <linux/debugfs.h>
50 typedef unsigned int pending_ring_idx_t;
51 #define INVALID_PENDING_RING_IDX (~0U)
53 struct pending_tx_info {
54 struct xen_netif_tx_request req; /* tx request */
55 unsigned int extra_count;
56 /* Callback data for released SKBs. The callback is always
57 * xenvif_zerocopy_callback, desc contains the pending_idx, which is
58 * also an index in pending_tx_info array. It is initialized in
59 * xenvif_alloc and it never changes.
60 * skb_shinfo(skb)->destructor_arg points to the first mapped slot's
61 * callback_struct in this array of struct pending_tx_info's, then ctx
62 * to the next, or NULL if there is no more slot for this skb.
63 * ubuf_to_vif is a helper which finds the struct xenvif from a pointer
66 struct ubuf_info callback_struct;
69 #define XEN_NETIF_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, XEN_PAGE_SIZE)
70 #define XEN_NETIF_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, XEN_PAGE_SIZE)
72 struct xenvif_rx_meta {
79 #define GSO_BIT(type) \
80 (1 << XEN_NETIF_GSO_TYPE_ ## type)
82 /* Discriminate from any valid pending_idx value. */
83 #define INVALID_PENDING_IDX 0xFFFF
85 #define MAX_BUFFER_OFFSET XEN_PAGE_SIZE
87 #define MAX_PENDING_REQS XEN_NETIF_TX_RING_SIZE
89 /* The maximum number of frags is derived from the size of a grant (same
90 * as a Xen page size for now).
92 #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1)
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.
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 #define COPY_BATCH_SIZE 64
131 struct xenvif_copy_state {
132 struct gnttab_copy op[COPY_BATCH_SIZE];
133 RING_IDX idx[COPY_BATCH_SIZE];
135 struct sk_buff_head *completed;
138 struct xenvif_queue { /* Per-queue data for xenvif */
139 unsigned int id; /* Queue ID, 0-based */
140 char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */
141 struct xenvif *vif; /* Parent VIF */
144 * TX/RX common EOI handling.
145 * When feature-split-event-channels = 0, interrupt handler sets
146 * NETBK_COMMON_EOI, otherwise NETBK_RX_EOI and NETBK_TX_EOI are set
147 * by the RX and TX interrupt handlers.
148 * RX and TX handler threads will issue an EOI when either
149 * NETBK_COMMON_EOI or their specific bits (NETBK_RX_EOI or
150 * NETBK_TX_EOI) are set and they will reset those bits.
152 atomic_t eoi_pending;
153 #define NETBK_RX_EOI 0x01
154 #define NETBK_TX_EOI 0x02
155 #define NETBK_COMMON_EOI 0x04
157 /* Use NAPI for guest TX */
158 struct napi_struct napi;
159 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */
161 /* Only used when feature-split-event-channels = 1 */
162 char tx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-tx */
163 struct xen_netif_tx_back_ring tx;
164 struct sk_buff_head tx_queue;
165 struct page *mmap_pages[MAX_PENDING_REQS];
166 pending_ring_idx_t pending_prod;
167 pending_ring_idx_t pending_cons;
168 u16 pending_ring[MAX_PENDING_REQS];
169 struct pending_tx_info pending_tx_info[MAX_PENDING_REQS];
170 grant_handle_t grant_tx_handle[MAX_PENDING_REQS];
172 struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS];
173 struct gnttab_map_grant_ref tx_map_ops[MAX_PENDING_REQS];
174 struct gnttab_unmap_grant_ref tx_unmap_ops[MAX_PENDING_REQS];
175 /* passed to gnttab_[un]map_refs with pages under (un)mapping */
176 struct page *pages_to_map[MAX_PENDING_REQS];
177 struct page *pages_to_unmap[MAX_PENDING_REQS];
179 /* This prevents zerocopy callbacks to race over dealloc_ring */
180 spinlock_t callback_lock;
181 /* This prevents dealloc thread and NAPI instance to race over response
182 * creation and pending_ring in xenvif_idx_release. In xenvif_tx_err
183 * it only protect response creation
185 spinlock_t response_lock;
186 pending_ring_idx_t dealloc_prod;
187 pending_ring_idx_t dealloc_cons;
188 u16 dealloc_ring[MAX_PENDING_REQS];
189 struct task_struct *dealloc_task;
190 wait_queue_head_t dealloc_wq;
191 atomic_t inflight_packets;
193 /* Use kthread for guest RX */
194 struct task_struct *task;
195 wait_queue_head_t wq;
196 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */
198 /* Only used when feature-split-event-channels = 1 */
199 char rx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */
200 struct xen_netif_rx_back_ring rx;
201 struct sk_buff_head rx_queue;
203 unsigned int rx_queue_max;
204 unsigned int rx_queue_len;
205 unsigned long last_rx_time;
208 struct xenvif_copy_state rx_copy;
210 /* Transmit shaping: allow 'credit_bytes' every 'credit_usec'. */
211 unsigned long credit_bytes;
212 unsigned long credit_usec;
213 unsigned long remaining_credit;
214 struct timer_list credit_timeout;
215 u64 credit_window_start;
219 struct xenvif_stats stats;
222 enum state_bit_shift {
223 /* This bit marks that the vif is connected */
224 VIF_STATUS_CONNECTED,
227 struct xenvif_mcast_addr {
228 struct list_head entry;
233 #define XEN_NETBK_MCAST_MAX 64
235 #define XEN_NETBK_MAX_HASH_KEY_SIZE 40
236 #define XEN_NETBK_MAX_HASH_MAPPING_SIZE 128
237 #define XEN_NETBK_HASH_TAG_SIZE 40
239 struct xenvif_hash_cache_entry {
240 struct list_head link;
242 u8 tag[XEN_NETBK_HASH_TAG_SIZE];
248 struct xenvif_hash_cache {
250 struct list_head list;
258 u8 key[XEN_NETBK_MAX_HASH_KEY_SIZE];
259 u32 mapping[XEN_NETBK_MAX_HASH_MAPPING_SIZE];
261 struct xenvif_hash_cache cache;
265 /* Unique identifier for this interface. */
270 struct list_head fe_mcast_addr;
271 unsigned int fe_mcast_count;
273 /* Frontend feature information. */
279 u8 multicast_control:1;
281 /* Is this interface disabled? True when backend discovers
285 unsigned long status;
286 unsigned long drain_timeout;
287 unsigned long stall_timeout;
290 struct xenvif_queue *queues;
291 unsigned int num_queues; /* active queues, resource allocated */
292 unsigned int stalled_queues;
294 struct xenvif_hash hash;
296 struct xenbus_watch credit_watch;
297 struct xenbus_watch mcast_ctrl_watch;
301 #ifdef CONFIG_DEBUG_FS
302 struct dentry *xenvif_dbg_root;
305 struct xen_netif_ctrl_back_ring ctrl;
306 unsigned int ctrl_irq;
308 /* Miscellaneous private stuff. */
309 struct net_device *dev;
312 struct xenvif_rx_cb {
313 unsigned long expires;
317 #define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb)
319 static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif)
321 return to_xenbus_device(vif->dev->dev.parent);
324 void xenvif_tx_credit_callback(unsigned long data);
326 struct xenvif *xenvif_alloc(struct device *parent,
328 unsigned int handle);
330 int xenvif_init_queue(struct xenvif_queue *queue);
331 void xenvif_deinit_queue(struct xenvif_queue *queue);
333 int xenvif_connect_data(struct xenvif_queue *queue,
334 unsigned long tx_ring_ref,
335 unsigned long rx_ring_ref,
336 unsigned int tx_evtchn,
337 unsigned int rx_evtchn);
338 void xenvif_disconnect_data(struct xenvif *vif);
339 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref,
340 unsigned int evtchn);
341 void xenvif_disconnect_ctrl(struct xenvif *vif);
342 void xenvif_free(struct xenvif *vif);
344 int xenvif_xenbus_init(void);
345 void xenvif_xenbus_fini(void);
347 int xenvif_schedulable(struct xenvif *vif);
349 int xenvif_queue_stopped(struct xenvif_queue *queue);
350 void xenvif_wake_queue(struct xenvif_queue *queue);
352 /* (Un)Map communication rings. */
353 void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue);
354 int xenvif_map_frontend_data_rings(struct xenvif_queue *queue,
355 grant_ref_t tx_ring_ref,
356 grant_ref_t rx_ring_ref);
358 /* Check for SKBs from frontend and schedule backend processing */
359 void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue);
361 /* Prevent the device from generating any further traffic. */
362 void xenvif_carrier_off(struct xenvif *vif);
364 int xenvif_tx_action(struct xenvif_queue *queue, int budget);
366 int xenvif_kthread_guest_rx(void *data);
367 void xenvif_kick_thread(struct xenvif_queue *queue);
369 int xenvif_dealloc_kthread(void *data);
371 irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data);
373 bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread);
374 void xenvif_rx_action(struct xenvif_queue *queue);
375 void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb);
377 void xenvif_carrier_on(struct xenvif *vif);
379 /* Callback from stack when TX packet can be released */
380 void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success);
382 /* Unmap a pending page and release it back to the guest */
383 void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx);
385 static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue)
387 return MAX_PENDING_REQS -
388 queue->pending_prod + queue->pending_cons;
391 irqreturn_t xenvif_interrupt(int irq, void *dev_id);
393 extern bool separate_tx_rx_irq;
395 extern unsigned int rx_drain_timeout_msecs;
396 extern unsigned int rx_stall_timeout_msecs;
397 extern unsigned int xenvif_max_queues;
398 extern unsigned int xenvif_hash_cache_size;
400 #ifdef CONFIG_DEBUG_FS
401 extern struct dentry *xen_netback_dbg_root;
404 void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue,
405 struct sk_buff *skb);
406 void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue);
408 /* Multicast control */
409 bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr);
410 void xenvif_mcast_addr_list_free(struct xenvif *vif);
413 void xenvif_init_hash(struct xenvif *vif);
414 void xenvif_deinit_hash(struct xenvif *vif);
416 u32 xenvif_set_hash_alg(struct xenvif *vif, u32 alg);
417 u32 xenvif_get_hash_flags(struct xenvif *vif, u32 *flags);
418 u32 xenvif_set_hash_flags(struct xenvif *vif, u32 flags);
419 u32 xenvif_set_hash_key(struct xenvif *vif, u32 gref, u32 len);
420 u32 xenvif_set_hash_mapping_size(struct xenvif *vif, u32 size);
421 u32 xenvif_set_hash_mapping(struct xenvif *vif, u32 gref, u32 len,
424 void xenvif_set_skb_hash(struct xenvif *vif, struct sk_buff *skb);
426 #ifdef CONFIG_DEBUG_FS
427 void xenvif_dump_hash_info(struct xenvif *vif, struct seq_file *m);
430 #endif /* __XEN_NETBACK__COMMON_H__ */