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 #include <xen/page.h> 48 #include <linux/debugfs.h> 49 50 typedef unsigned int pending_ring_idx_t; 51 52 struct pending_tx_info { 53 struct xen_netif_tx_request req; /* tx request */ 54 unsigned int extra_count; 55 /* Callback data for released SKBs. The callback is always 56 * xenvif_zerocopy_callback, desc contains the pending_idx, which is 57 * also an index in pending_tx_info array. It is initialized in 58 * xenvif_alloc and it never changes. 59 * skb_shinfo(skb)->destructor_arg points to the first mapped slot's 60 * callback_struct in this array of struct pending_tx_info's, then ctx 61 * to the next, or NULL if there is no more slot for this skb. 62 * ubuf_to_vif is a helper which finds the struct xenvif from a pointer 63 * to this field. 64 */ 65 struct ubuf_info_msgzc callback_struct; 66 }; 67 68 #define XEN_NETIF_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, XEN_PAGE_SIZE) 69 #define XEN_NETIF_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, XEN_PAGE_SIZE) 70 71 struct xenvif_rx_meta { 72 int id; 73 int size; 74 int gso_type; 75 int gso_size; 76 }; 77 78 #define GSO_BIT(type) \ 79 (1 << XEN_NETIF_GSO_TYPE_ ## type) 80 81 /* Discriminate from any valid pending_idx value. */ 82 #define INVALID_PENDING_IDX 0xFFFF 83 84 #define MAX_PENDING_REQS XEN_NETIF_TX_RING_SIZE 85 86 /* The maximum number of frags is derived from the size of a grant (same 87 * as a Xen page size for now). 88 */ 89 #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1) 90 91 #define NETBACK_INVALID_HANDLE -1 92 93 /* To avoid confusion, we define XEN_NETBK_LEGACY_SLOTS_MAX indicating 94 * the maximum slots a valid packet can use. Now this value is defined 95 * to be XEN_NETIF_NR_SLOTS_MIN, which is supposed to be supported by 96 * all backend. 97 */ 98 #define XEN_NETBK_LEGACY_SLOTS_MAX XEN_NETIF_NR_SLOTS_MIN 99 100 /* Queue name is interface name with "-qNNN" appended */ 101 #define QUEUE_NAME_SIZE (IFNAMSIZ + 5) 102 103 /* IRQ name is queue name with "-tx" or "-rx" appended */ 104 #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3) 105 106 struct xenvif; 107 108 struct xenvif_stats { 109 /* Stats fields to be updated per-queue. 110 * A subset of struct net_device_stats that contains only the 111 * fields that are updated in netback.c for each queue. 112 */ 113 u64 rx_bytes; 114 u64 rx_packets; 115 u64 tx_bytes; 116 u64 tx_packets; 117 118 /* Additional stats used by xenvif */ 119 unsigned long rx_gso_checksum_fixup; 120 unsigned long tx_zerocopy_sent; 121 unsigned long tx_zerocopy_success; 122 unsigned long tx_zerocopy_fail; 123 unsigned long tx_frag_overflow; 124 }; 125 126 #define COPY_BATCH_SIZE 64 127 128 struct xenvif_copy_state { 129 struct gnttab_copy op[COPY_BATCH_SIZE]; 130 RING_IDX idx[COPY_BATCH_SIZE]; 131 unsigned int num; 132 struct sk_buff_head *completed; 133 }; 134 135 struct xenvif_queue { /* Per-queue data for xenvif */ 136 unsigned int id; /* Queue ID, 0-based */ 137 char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */ 138 struct xenvif *vif; /* Parent VIF */ 139 140 /* 141 * TX/RX common EOI handling. 142 * When feature-split-event-channels = 0, interrupt handler sets 143 * NETBK_COMMON_EOI, otherwise NETBK_RX_EOI and NETBK_TX_EOI are set 144 * by the RX and TX interrupt handlers. 145 * RX and TX handler threads will issue an EOI when either 146 * NETBK_COMMON_EOI or their specific bits (NETBK_RX_EOI or 147 * NETBK_TX_EOI) are set and they will reset those bits. 148 */ 149 atomic_t eoi_pending; 150 #define NETBK_RX_EOI 0x01 151 #define NETBK_TX_EOI 0x02 152 #define NETBK_COMMON_EOI 0x04 153 154 /* Use NAPI for guest TX */ 155 struct napi_struct napi; 156 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ 157 unsigned int tx_irq; 158 /* Only used when feature-split-event-channels = 1 */ 159 char tx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-tx */ 160 struct xen_netif_tx_back_ring tx; 161 struct sk_buff_head tx_queue; 162 struct page *mmap_pages[MAX_PENDING_REQS]; 163 pending_ring_idx_t pending_prod; 164 pending_ring_idx_t pending_cons; 165 u16 pending_ring[MAX_PENDING_REQS]; 166 struct pending_tx_info pending_tx_info[MAX_PENDING_REQS]; 167 grant_handle_t grant_tx_handle[MAX_PENDING_REQS]; 168 169 struct gnttab_copy tx_copy_ops[2 * MAX_PENDING_REQS]; 170 struct gnttab_map_grant_ref tx_map_ops[MAX_PENDING_REQS]; 171 struct gnttab_unmap_grant_ref tx_unmap_ops[MAX_PENDING_REQS]; 172 /* passed to gnttab_[un]map_refs with pages under (un)mapping */ 173 struct page *pages_to_map[MAX_PENDING_REQS]; 174 struct page *pages_to_unmap[MAX_PENDING_REQS]; 175 176 /* This prevents zerocopy callbacks to race over dealloc_ring */ 177 spinlock_t callback_lock; 178 /* This prevents dealloc thread and NAPI instance to race over response 179 * creation and pending_ring in xenvif_idx_release. In xenvif_tx_err 180 * it only protect response creation 181 */ 182 spinlock_t response_lock; 183 pending_ring_idx_t dealloc_prod; 184 pending_ring_idx_t dealloc_cons; 185 u16 dealloc_ring[MAX_PENDING_REQS]; 186 struct task_struct *dealloc_task; 187 wait_queue_head_t dealloc_wq; 188 atomic_t inflight_packets; 189 190 /* Use kthread for guest RX */ 191 struct task_struct *task; 192 wait_queue_head_t wq; 193 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ 194 unsigned int rx_irq; 195 /* Only used when feature-split-event-channels = 1 */ 196 char rx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */ 197 struct xen_netif_rx_back_ring rx; 198 struct sk_buff_head rx_queue; 199 200 unsigned int rx_queue_max; 201 unsigned int rx_queue_len; 202 unsigned long last_rx_time; 203 unsigned int rx_slots_needed; 204 bool stalled; 205 206 struct xenvif_copy_state rx_copy; 207 208 /* Transmit shaping: allow 'credit_bytes' every 'credit_usec'. */ 209 unsigned long credit_bytes; 210 unsigned long credit_usec; 211 unsigned long remaining_credit; 212 struct timer_list credit_timeout; 213 u64 credit_window_start; 214 bool rate_limited; 215 216 /* Statistics */ 217 struct xenvif_stats stats; 218 }; 219 220 enum state_bit_shift { 221 /* This bit marks that the vif is connected */ 222 VIF_STATUS_CONNECTED, 223 }; 224 225 struct xenvif_mcast_addr { 226 struct list_head entry; 227 struct rcu_head rcu; 228 u8 addr[6]; 229 }; 230 231 #define XEN_NETBK_MCAST_MAX 64 232 233 #define XEN_NETBK_MAX_HASH_KEY_SIZE 40 234 #define XEN_NETBK_MAX_HASH_MAPPING_SIZE 128 235 #define XEN_NETBK_HASH_TAG_SIZE 40 236 237 struct xenvif_hash_cache_entry { 238 struct list_head link; 239 struct rcu_head rcu; 240 u8 tag[XEN_NETBK_HASH_TAG_SIZE]; 241 unsigned int len; 242 u32 val; 243 int seq; 244 }; 245 246 struct xenvif_hash_cache { 247 spinlock_t lock; 248 struct list_head list; 249 unsigned int count; 250 atomic_t seq; 251 }; 252 253 struct xenvif_hash { 254 unsigned int alg; 255 u32 flags; 256 bool mapping_sel; 257 u8 key[XEN_NETBK_MAX_HASH_KEY_SIZE]; 258 u32 mapping[2][XEN_NETBK_MAX_HASH_MAPPING_SIZE]; 259 unsigned int size; 260 struct xenvif_hash_cache cache; 261 }; 262 263 struct backend_info { 264 struct xenbus_device *dev; 265 struct xenvif *vif; 266 267 /* This is the state that will be reflected in xenstore when any 268 * active hotplug script completes. 269 */ 270 enum xenbus_state state; 271 272 enum xenbus_state frontend_state; 273 struct xenbus_watch hotplug_status_watch; 274 u8 have_hotplug_status_watch:1; 275 276 const char *hotplug_script; 277 }; 278 279 struct xenvif { 280 /* Unique identifier for this interface. */ 281 domid_t domid; 282 unsigned int handle; 283 284 u8 fe_dev_addr[6]; 285 struct list_head fe_mcast_addr; 286 unsigned int fe_mcast_count; 287 288 /* Frontend feature information. */ 289 int gso_mask; 290 291 u8 can_sg:1; 292 u8 ip_csum:1; 293 u8 ipv6_csum:1; 294 u8 multicast_control:1; 295 296 /* headroom requested by xen-netfront */ 297 u16 xdp_headroom; 298 299 /* Is this interface disabled? True when backend discovers 300 * frontend is rogue. 301 */ 302 bool disabled; 303 unsigned long status; 304 unsigned long drain_timeout; 305 unsigned long stall_timeout; 306 307 /* Queues */ 308 struct xenvif_queue *queues; 309 unsigned int num_queues; /* active queues, resource allocated */ 310 unsigned int stalled_queues; 311 312 struct xenvif_hash hash; 313 314 struct xenbus_watch credit_watch; 315 struct xenbus_watch mcast_ctrl_watch; 316 317 struct backend_info *be; 318 319 spinlock_t lock; 320 321 #ifdef CONFIG_DEBUG_FS 322 struct dentry *xenvif_dbg_root; 323 #endif 324 325 struct xen_netif_ctrl_back_ring ctrl; 326 unsigned int ctrl_irq; 327 328 /* Miscellaneous private stuff. */ 329 struct net_device *dev; 330 }; 331 332 struct xenvif_rx_cb { 333 unsigned long expires; 334 int meta_slots_used; 335 }; 336 337 #define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb) 338 xenvif_to_xenbus_device(struct xenvif * vif)339 static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif) 340 { 341 return to_xenbus_device(vif->dev->dev.parent); 342 } 343 344 void xenvif_tx_credit_callback(struct timer_list *t); 345 346 struct xenvif *xenvif_alloc(struct device *parent, 347 domid_t domid, 348 unsigned int handle); 349 350 int xenvif_init_queue(struct xenvif_queue *queue); 351 void xenvif_deinit_queue(struct xenvif_queue *queue); 352 353 int xenvif_connect_data(struct xenvif_queue *queue, 354 unsigned long tx_ring_ref, 355 unsigned long rx_ring_ref, 356 unsigned int tx_evtchn, 357 unsigned int rx_evtchn); 358 void xenvif_disconnect_data(struct xenvif *vif); 359 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 360 unsigned int evtchn); 361 void xenvif_disconnect_ctrl(struct xenvif *vif); 362 void xenvif_free(struct xenvif *vif); 363 364 int xenvif_xenbus_init(void); 365 void xenvif_xenbus_fini(void); 366 367 /* (Un)Map communication rings. */ 368 void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue); 369 int xenvif_map_frontend_data_rings(struct xenvif_queue *queue, 370 grant_ref_t tx_ring_ref, 371 grant_ref_t rx_ring_ref); 372 373 /* Check for SKBs from frontend and schedule backend processing */ 374 void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue); 375 376 /* Prevent the device from generating any further traffic. */ 377 void xenvif_carrier_off(struct xenvif *vif); 378 379 int xenvif_tx_action(struct xenvif_queue *queue, int budget); 380 381 int xenvif_kthread_guest_rx(void *data); 382 void xenvif_kick_thread(struct xenvif_queue *queue); 383 384 int xenvif_dealloc_kthread(void *data); 385 386 irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data); 387 388 bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread); 389 bool xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb); 390 391 void xenvif_carrier_on(struct xenvif *vif); 392 393 /* Callbacks from stack when TX packet can be released */ 394 extern const struct ubuf_info_ops xenvif_ubuf_ops; 395 nr_pending_reqs(struct xenvif_queue * queue)396 static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue) 397 { 398 return MAX_PENDING_REQS - 399 queue->pending_prod + queue->pending_cons; 400 } 401 402 irqreturn_t xenvif_interrupt(int irq, void *dev_id); 403 404 extern bool separate_tx_rx_irq; 405 extern bool provides_xdp_headroom; 406 407 extern unsigned int rx_drain_timeout_msecs; 408 extern unsigned int rx_stall_timeout_msecs; 409 extern unsigned int xenvif_max_queues; 410 extern unsigned int xenvif_hash_cache_size; 411 412 #ifdef CONFIG_DEBUG_FS 413 extern struct dentry *xen_netback_dbg_root; 414 #endif 415 416 void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue, 417 struct sk_buff *skb); 418 void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue); 419 420 /* Multicast control */ 421 bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr); 422 void xenvif_mcast_addr_list_free(struct xenvif *vif); 423 424 /* Hash */ 425 void xenvif_init_hash(struct xenvif *vif); 426 void xenvif_deinit_hash(struct xenvif *vif); 427 428 u32 xenvif_set_hash_alg(struct xenvif *vif, u32 alg); 429 u32 xenvif_get_hash_flags(struct xenvif *vif, u32 *flags); 430 u32 xenvif_set_hash_flags(struct xenvif *vif, u32 flags); 431 u32 xenvif_set_hash_key(struct xenvif *vif, u32 gref, u32 len); 432 u32 xenvif_set_hash_mapping_size(struct xenvif *vif, u32 size); 433 u32 xenvif_set_hash_mapping(struct xenvif *vif, u32 gref, u32 len, 434 u32 off); 435 436 void xenvif_set_skb_hash(struct xenvif *vif, struct sk_buff *skb); 437 438 #ifdef CONFIG_DEBUG_FS 439 void xenvif_dump_hash_info(struct xenvif *vif, struct seq_file *m); 440 #endif 441 442 #endif /* __XEN_NETBACK__COMMON_H__ */ 443