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 /* It's possible for an skb to have a maximal number of frags 95 * but still be less than MAX_BUFFER_OFFSET in size. Thus the 96 * worst-case number of copy operations is MAX_XEN_SKB_FRAGS per 97 * ring slot. 98 */ 99 #define MAX_GRANT_COPY_OPS (MAX_XEN_SKB_FRAGS * XEN_NETIF_RX_RING_SIZE) 100 101 #define NETBACK_INVALID_HANDLE -1 102 103 /* To avoid confusion, we define XEN_NETBK_LEGACY_SLOTS_MAX indicating 104 * the maximum slots a valid packet can use. Now this value is defined 105 * to be XEN_NETIF_NR_SLOTS_MIN, which is supposed to be supported by 106 * all backend. 107 */ 108 #define XEN_NETBK_LEGACY_SLOTS_MAX XEN_NETIF_NR_SLOTS_MIN 109 110 /* Queue name is interface name with "-qNNN" appended */ 111 #define QUEUE_NAME_SIZE (IFNAMSIZ + 5) 112 113 /* IRQ name is queue name with "-tx" or "-rx" appended */ 114 #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3) 115 116 struct xenvif; 117 118 struct xenvif_stats { 119 /* Stats fields to be updated per-queue. 120 * A subset of struct net_device_stats that contains only the 121 * fields that are updated in netback.c for each queue. 122 */ 123 unsigned int rx_bytes; 124 unsigned int rx_packets; 125 unsigned int tx_bytes; 126 unsigned int tx_packets; 127 128 /* Additional stats used by xenvif */ 129 unsigned long rx_gso_checksum_fixup; 130 unsigned long tx_zerocopy_sent; 131 unsigned long tx_zerocopy_success; 132 unsigned long tx_zerocopy_fail; 133 unsigned long tx_frag_overflow; 134 }; 135 136 struct xenvif_queue { /* Per-queue data for xenvif */ 137 unsigned int id; /* Queue ID, 0-based */ 138 char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */ 139 struct xenvif *vif; /* Parent VIF */ 140 141 /* Use NAPI for guest TX */ 142 struct napi_struct napi; 143 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ 144 unsigned int tx_irq; 145 /* Only used when feature-split-event-channels = 1 */ 146 char tx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-tx */ 147 struct xen_netif_tx_back_ring tx; 148 struct sk_buff_head tx_queue; 149 struct page *mmap_pages[MAX_PENDING_REQS]; 150 pending_ring_idx_t pending_prod; 151 pending_ring_idx_t pending_cons; 152 u16 pending_ring[MAX_PENDING_REQS]; 153 struct pending_tx_info pending_tx_info[MAX_PENDING_REQS]; 154 grant_handle_t grant_tx_handle[MAX_PENDING_REQS]; 155 156 struct gnttab_copy tx_copy_ops[MAX_PENDING_REQS]; 157 struct gnttab_map_grant_ref tx_map_ops[MAX_PENDING_REQS]; 158 struct gnttab_unmap_grant_ref tx_unmap_ops[MAX_PENDING_REQS]; 159 /* passed to gnttab_[un]map_refs with pages under (un)mapping */ 160 struct page *pages_to_map[MAX_PENDING_REQS]; 161 struct page *pages_to_unmap[MAX_PENDING_REQS]; 162 163 /* This prevents zerocopy callbacks to race over dealloc_ring */ 164 spinlock_t callback_lock; 165 /* This prevents dealloc thread and NAPI instance to race over response 166 * creation and pending_ring in xenvif_idx_release. In xenvif_tx_err 167 * it only protect response creation 168 */ 169 spinlock_t response_lock; 170 pending_ring_idx_t dealloc_prod; 171 pending_ring_idx_t dealloc_cons; 172 u16 dealloc_ring[MAX_PENDING_REQS]; 173 struct task_struct *dealloc_task; 174 wait_queue_head_t dealloc_wq; 175 atomic_t inflight_packets; 176 177 /* Use kthread for guest RX */ 178 struct task_struct *task; 179 wait_queue_head_t wq; 180 /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ 181 unsigned int rx_irq; 182 /* Only used when feature-split-event-channels = 1 */ 183 char rx_irq_name[IRQ_NAME_SIZE]; /* DEVNAME-qN-rx */ 184 struct xen_netif_rx_back_ring rx; 185 struct sk_buff_head rx_queue; 186 187 unsigned int rx_queue_max; 188 unsigned int rx_queue_len; 189 unsigned long last_rx_time; 190 bool stalled; 191 192 struct gnttab_copy grant_copy_op[MAX_GRANT_COPY_OPS]; 193 194 /* We create one meta structure per ring request we consume, so 195 * the maximum number is the same as the ring size. 196 */ 197 struct xenvif_rx_meta meta[XEN_NETIF_RX_RING_SIZE]; 198 199 /* Transmit shaping: allow 'credit_bytes' every 'credit_usec'. */ 200 unsigned long credit_bytes; 201 unsigned long credit_usec; 202 unsigned long remaining_credit; 203 struct timer_list credit_timeout; 204 u64 credit_window_start; 205 206 /* Statistics */ 207 struct xenvif_stats stats; 208 }; 209 210 enum state_bit_shift { 211 /* This bit marks that the vif is connected */ 212 VIF_STATUS_CONNECTED, 213 }; 214 215 struct xenvif_mcast_addr { 216 struct list_head entry; 217 struct rcu_head rcu; 218 u8 addr[6]; 219 }; 220 221 #define XEN_NETBK_MCAST_MAX 64 222 223 #define XEN_NETBK_MAX_HASH_KEY_SIZE 40 224 #define XEN_NETBK_MAX_HASH_MAPPING_SIZE 128 225 #define XEN_NETBK_HASH_TAG_SIZE 40 226 227 struct xenvif_hash_cache_entry { 228 struct list_head link; 229 struct rcu_head rcu; 230 u8 tag[XEN_NETBK_HASH_TAG_SIZE]; 231 unsigned int len; 232 u32 val; 233 int seq; 234 }; 235 236 struct xenvif_hash_cache { 237 spinlock_t lock; 238 struct list_head list; 239 unsigned int count; 240 atomic_t seq; 241 }; 242 243 struct xenvif_hash { 244 unsigned int alg; 245 u32 flags; 246 u8 key[XEN_NETBK_MAX_HASH_KEY_SIZE]; 247 u32 mapping[XEN_NETBK_MAX_HASH_MAPPING_SIZE]; 248 unsigned int size; 249 struct xenvif_hash_cache cache; 250 }; 251 252 struct xenvif { 253 /* Unique identifier for this interface. */ 254 domid_t domid; 255 unsigned int handle; 256 257 u8 fe_dev_addr[6]; 258 struct list_head fe_mcast_addr; 259 unsigned int fe_mcast_count; 260 261 /* Frontend feature information. */ 262 int gso_mask; 263 int gso_prefix_mask; 264 265 u8 can_sg:1; 266 u8 ip_csum:1; 267 u8 ipv6_csum:1; 268 u8 multicast_control:1; 269 270 /* Is this interface disabled? True when backend discovers 271 * frontend is rogue. 272 */ 273 bool disabled; 274 unsigned long status; 275 unsigned long drain_timeout; 276 unsigned long stall_timeout; 277 278 /* Queues */ 279 struct xenvif_queue *queues; 280 unsigned int num_queues; /* active queues, resource allocated */ 281 unsigned int stalled_queues; 282 283 struct xenvif_hash hash; 284 285 struct xenbus_watch credit_watch; 286 struct xenbus_watch mcast_ctrl_watch; 287 288 spinlock_t lock; 289 290 #ifdef CONFIG_DEBUG_FS 291 struct dentry *xenvif_dbg_root; 292 #endif 293 294 struct xen_netif_ctrl_back_ring ctrl; 295 struct task_struct *ctrl_task; 296 wait_queue_head_t ctrl_wq; 297 unsigned int ctrl_irq; 298 299 /* Miscellaneous private stuff. */ 300 struct net_device *dev; 301 }; 302 303 struct xenvif_rx_cb { 304 unsigned long expires; 305 int meta_slots_used; 306 }; 307 308 #define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb) 309 310 static inline struct xenbus_device *xenvif_to_xenbus_device(struct xenvif *vif) 311 { 312 return to_xenbus_device(vif->dev->dev.parent); 313 } 314 315 void xenvif_tx_credit_callback(unsigned long data); 316 317 struct xenvif *xenvif_alloc(struct device *parent, 318 domid_t domid, 319 unsigned int handle); 320 321 int xenvif_init_queue(struct xenvif_queue *queue); 322 void xenvif_deinit_queue(struct xenvif_queue *queue); 323 324 int xenvif_connect_data(struct xenvif_queue *queue, 325 unsigned long tx_ring_ref, 326 unsigned long rx_ring_ref, 327 unsigned int tx_evtchn, 328 unsigned int rx_evtchn); 329 void xenvif_disconnect_data(struct xenvif *vif); 330 int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 331 unsigned int evtchn); 332 void xenvif_disconnect_ctrl(struct xenvif *vif); 333 void xenvif_free(struct xenvif *vif); 334 335 int xenvif_xenbus_init(void); 336 void xenvif_xenbus_fini(void); 337 338 int xenvif_schedulable(struct xenvif *vif); 339 340 int xenvif_queue_stopped(struct xenvif_queue *queue); 341 void xenvif_wake_queue(struct xenvif_queue *queue); 342 343 /* (Un)Map communication rings. */ 344 void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue); 345 int xenvif_map_frontend_data_rings(struct xenvif_queue *queue, 346 grant_ref_t tx_ring_ref, 347 grant_ref_t rx_ring_ref); 348 349 /* Check for SKBs from frontend and schedule backend processing */ 350 void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue); 351 352 /* Prevent the device from generating any further traffic. */ 353 void xenvif_carrier_off(struct xenvif *vif); 354 355 int xenvif_tx_action(struct xenvif_queue *queue, int budget); 356 357 int xenvif_kthread_guest_rx(void *data); 358 void xenvif_kick_thread(struct xenvif_queue *queue); 359 360 int xenvif_dealloc_kthread(void *data); 361 362 int xenvif_ctrl_kthread(void *data); 363 364 void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb); 365 366 void xenvif_carrier_on(struct xenvif *vif); 367 368 /* Callback from stack when TX packet can be released */ 369 void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success); 370 371 /* Unmap a pending page and release it back to the guest */ 372 void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx); 373 374 static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue) 375 { 376 return MAX_PENDING_REQS - 377 queue->pending_prod + queue->pending_cons; 378 } 379 380 irqreturn_t xenvif_interrupt(int irq, void *dev_id); 381 382 extern bool separate_tx_rx_irq; 383 384 extern unsigned int rx_drain_timeout_msecs; 385 extern unsigned int rx_stall_timeout_msecs; 386 extern unsigned int xenvif_max_queues; 387 extern unsigned int xenvif_hash_cache_size; 388 389 #ifdef CONFIG_DEBUG_FS 390 extern struct dentry *xen_netback_dbg_root; 391 #endif 392 393 void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue, 394 struct sk_buff *skb); 395 void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue); 396 397 /* Multicast control */ 398 bool xenvif_mcast_match(struct xenvif *vif, const u8 *addr); 399 void xenvif_mcast_addr_list_free(struct xenvif *vif); 400 401 /* Hash */ 402 void xenvif_init_hash(struct xenvif *vif); 403 void xenvif_deinit_hash(struct xenvif *vif); 404 405 u32 xenvif_set_hash_alg(struct xenvif *vif, u32 alg); 406 u32 xenvif_get_hash_flags(struct xenvif *vif, u32 *flags); 407 u32 xenvif_set_hash_flags(struct xenvif *vif, u32 flags); 408 u32 xenvif_set_hash_key(struct xenvif *vif, u32 gref, u32 len); 409 u32 xenvif_set_hash_mapping_size(struct xenvif *vif, u32 size); 410 u32 xenvif_set_hash_mapping(struct xenvif *vif, u32 gref, u32 len, 411 u32 off); 412 413 void xenvif_set_skb_hash(struct xenvif *vif, struct sk_buff *skb); 414 415 #endif /* __XEN_NETBACK__COMMON_H__ */ 416