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 #define INVALID_PENDING_RING_IDX (~0U) 52 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 64 * to this field. 65 */ 66 struct ubuf_info callback_struct; 67 }; 68 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) 71 72 struct xenvif_rx_meta { 73 int id; 74 int size; 75 int gso_type; 76 int gso_size; 77 }; 78 79 #define GSO_BIT(type) \ 80 (1 << XEN_NETIF_GSO_TYPE_ ## type) 81 82 /* Discriminate from any valid pending_idx value. */ 83 #define INVALID_PENDING_IDX 0xFFFF 84 85 #define MAX_BUFFER_OFFSET XEN_PAGE_SIZE 86 87 #define MAX_PENDING_REQS XEN_NETIF_TX_RING_SIZE 88 89 /* The maximum number of frags is derived from the size of a grant (same 90 * as a Xen page size for now). 91 */ 92 #define MAX_XEN_SKB_FRAGS (65536 / XEN_PAGE_SIZE + 1) 93 94 #define NETBACK_INVALID_HANDLE -1 95 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 99 * all backend. 100 */ 101 #define XEN_NETBK_LEGACY_SLOTS_MAX XEN_NETIF_NR_SLOTS_MIN 102 103 /* Queue name is interface name with "-qNNN" appended */ 104 #define QUEUE_NAME_SIZE (IFNAMSIZ + 5) 105 106 /* IRQ name is queue name with "-tx" or "-rx" appended */ 107 #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3) 108 109 struct xenvif; 110 111 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. 115 */ 116 u64 rx_bytes; 117 u64 rx_packets; 118 u64 tx_bytes; 119 u64 tx_packets; 120 121 /* 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; 127 }; 128 129 #define COPY_BATCH_SIZE 64 130 131 struct xenvif_copy_state { 132 struct gnttab_copy op[COPY_BATCH_SIZE]; 133 RING_IDX idx[COPY_BATCH_SIZE]; 134 unsigned int num; 135 struct sk_buff_head *completed; 136 }; 137 138 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 */ 142 143 /* 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. 151 */ 152 atomic_t eoi_pending; 153 #define NETBK_RX_EOI 0x01 154 #define NETBK_TX_EOI 0x02 155 #define NETBK_COMMON_EOI 0x04 156 157 /* Use NAPI for guest TX */ 158 struct napi_struct napi; 159 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ 160 unsigned int tx_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]; 171 172 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]; 178 179 /* 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 184 */ 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; 192 193 /* 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. */ 197 unsigned int 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; 202 203 unsigned int rx_queue_max; 204 unsigned int rx_queue_len; 205 unsigned long last_rx_time; 206 bool stalled; 207 208 struct xenvif_copy_state rx_copy; 209 210 /* 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; 216 bool rate_limited; 217 218 /* Statistics */ 219 struct xenvif_stats stats; 220 }; 221 222 enum state_bit_shift { 223 /* This bit marks that the vif is connected */ 224 VIF_STATUS_CONNECTED, 225 }; 226 227 struct xenvif_mcast_addr { 228 struct list_head entry; 229 struct rcu_head rcu; 230 u8 addr[6]; 231 }; 232 233 #define XEN_NETBK_MCAST_MAX 64 234 235 #define XEN_NETBK_MAX_HASH_KEY_SIZE 40 236 #define XEN_NETBK_MAX_HASH_MAPPING_SIZE 128 237 #define XEN_NETBK_HASH_TAG_SIZE 40 238 239 struct xenvif_hash_cache_entry { 240 struct list_head link; 241 struct rcu_head rcu; 242 u8 tag[XEN_NETBK_HASH_TAG_SIZE]; 243 unsigned int len; 244 u32 val; 245 int seq; 246 }; 247 248 struct xenvif_hash_cache { 249 spinlock_t lock; 250 struct list_head list; 251 unsigned int count; 252 atomic_t seq; 253 }; 254 255 struct xenvif_hash { 256 unsigned int alg; 257 u32 flags; 258 bool mapping_sel; 259 u8 key[XEN_NETBK_MAX_HASH_KEY_SIZE]; 260 u32 mapping[2][XEN_NETBK_MAX_HASH_MAPPING_SIZE]; 261 unsigned int size; 262 struct xenvif_hash_cache cache; 263 }; 264 265 struct backend_info { 266 struct xenbus_device *dev; 267 struct xenvif *vif; 268 269 /* This is the state that will be reflected in xenstore when any 270 * active hotplug script completes. 271 */ 272 enum xenbus_state state; 273 274 enum xenbus_state frontend_state; 275 struct xenbus_watch hotplug_status_watch; 276 u8 have_hotplug_status_watch:1; 277 278 const char *hotplug_script; 279 }; 280 281 struct xenvif { 282 /* Unique identifier for this interface. */ 283 domid_t domid; 284 unsigned int handle; 285 286 u8 fe_dev_addr[6]; 287 struct list_head fe_mcast_addr; 288 unsigned int fe_mcast_count; 289 290 /* Frontend feature information. */ 291 int gso_mask; 292 293 u8 can_sg:1; 294 u8 ip_csum:1; 295 u8 ipv6_csum:1; 296 u8 multicast_control:1; 297 298 /* headroom requested by xen-netfront */ 299 u16 xdp_headroom; 300 301 /* Is this interface disabled? True when backend discovers 302 * frontend is rogue. 303 */ 304 bool disabled; 305 unsigned long status; 306 unsigned long drain_timeout; 307 unsigned long stall_timeout; 308 309 /* Queues */ 310 struct xenvif_queue *queues; 311 unsigned int num_queues; /* active queues, resource allocated */ 312 unsigned int stalled_queues; 313 314 struct xenvif_hash hash; 315 316 struct xenbus_watch credit_watch; 317 struct xenbus_watch mcast_ctrl_watch; 318 319 struct backend_info *be; 320 321 spinlock_t lock; 322 323 #ifdef CONFIG_DEBUG_FS 324 struct dentry *xenvif_dbg_root; 325 #endif 326 327 struct xen_netif_ctrl_back_ring ctrl; 328 unsigned int ctrl_irq; 329 330 /* Miscellaneous private stuff. */ 331 struct net_device *dev; 332 }; 333 334 struct xenvif_rx_cb { 335 unsigned long expires; 336 int meta_slots_used; 337 }; 338 339 #define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb) 340 341 static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif) 342 { 343 return to_xenbus_device(vif->dev->dev.parent); 344 } 345 346 void xenvif_tx_credit_callback(struct timer_list *t); 347 348 struct xenvif *xenvif_alloc(struct device *parent, 349 domid_t domid, 350 unsigned int handle); 351 352 int xenvif_init_queue(struct xenvif_queue *queue); 353 void xenvif_deinit_queue(struct xenvif_queue *queue); 354 355 int xenvif_connect_data(struct xenvif_queue *queue, 356 unsigned long tx_ring_ref, 357 unsigned long rx_ring_ref, 358 unsigned int tx_evtchn, 359 unsigned int rx_evtchn); 360 void xenvif_disconnect_data(struct xenvif *vif); 361 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 362 unsigned int evtchn); 363 void xenvif_disconnect_ctrl(struct xenvif *vif); 364 void xenvif_free(struct xenvif *vif); 365 366 int xenvif_xenbus_init(void); 367 void xenvif_xenbus_fini(void); 368 369 int xenvif_schedulable(struct xenvif *vif); 370 371 int xenvif_queue_stopped(struct xenvif_queue *queue); 372 void xenvif_wake_queue(struct xenvif_queue *queue); 373 374 /* (Un)Map communication rings. */ 375 void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue); 376 int xenvif_map_frontend_data_rings(struct xenvif_queue *queue, 377 grant_ref_t tx_ring_ref, 378 grant_ref_t rx_ring_ref); 379 380 /* Check for SKBs from frontend and schedule backend processing */ 381 void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue); 382 383 /* Prevent the device from generating any further traffic. */ 384 void xenvif_carrier_off(struct xenvif *vif); 385 386 int xenvif_tx_action(struct xenvif_queue *queue, int budget); 387 388 int xenvif_kthread_guest_rx(void *data); 389 void xenvif_kick_thread(struct xenvif_queue *queue); 390 391 int xenvif_dealloc_kthread(void *data); 392 393 irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data); 394 395 bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread); 396 void xenvif_rx_action(struct xenvif_queue *queue); 397 void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb); 398 399 void xenvif_carrier_on(struct xenvif *vif); 400 401 /* Callback from stack when TX packet can be released */ 402 void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success); 403 404 /* Unmap a pending page and release it back to the guest */ 405 void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx); 406 407 static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue) 408 { 409 return MAX_PENDING_REQS - 410 queue->pending_prod + queue->pending_cons; 411 } 412 413 irqreturn_t xenvif_interrupt(int irq, void *dev_id); 414 415 extern bool separate_tx_rx_irq; 416 extern bool provides_xdp_headroom; 417 418 extern unsigned int rx_drain_timeout_msecs; 419 extern unsigned int rx_stall_timeout_msecs; 420 extern unsigned int xenvif_max_queues; 421 extern unsigned int xenvif_hash_cache_size; 422 423 #ifdef CONFIG_DEBUG_FS 424 extern struct dentry *xen_netback_dbg_root; 425 #endif 426 427 void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue, 428 struct sk_buff *skb); 429 void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue); 430 431 /* Multicast control */ 432 bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr); 433 void xenvif_mcast_addr_list_free(struct xenvif *vif); 434 435 /* Hash */ 436 void xenvif_init_hash(struct xenvif *vif); 437 void xenvif_deinit_hash(struct xenvif *vif); 438 439 u32 xenvif_set_hash_alg(struct xenvif *vif, u32 alg); 440 u32 xenvif_get_hash_flags(struct xenvif *vif, u32 *flags); 441 u32 xenvif_set_hash_flags(struct xenvif *vif, u32 flags); 442 u32 xenvif_set_hash_key(struct xenvif *vif, u32 gref, u32 len); 443 u32 xenvif_set_hash_mapping_size(struct xenvif *vif, u32 size); 444 u32 xenvif_set_hash_mapping(struct xenvif *vif, u32 gref, u32 len, 445 u32 off); 446 447 void xenvif_set_skb_hash(struct xenvif *vif, struct sk_buff *skb); 448 449 #ifdef CONFIG_DEBUG_FS 450 void xenvif_dump_hash_info(struct xenvif *vif, struct seq_file *m); 451 #endif 452 453 #endif /* __XEN_NETBACK__COMMON_H__ */ 454