1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * 4 * Copyright (c) 2011, Microsoft Corporation. 5 * 6 * Authors: 7 * Haiyang Zhang <haiyangz@microsoft.com> 8 * Hank Janssen <hjanssen@microsoft.com> 9 * K. Y. Srinivasan <kys@microsoft.com> 10 */ 11 12 #ifndef _HYPERV_VMBUS_H 13 #define _HYPERV_VMBUS_H 14 15 #include <linux/list.h> 16 #include <linux/bitops.h> 17 #include <asm/sync_bitops.h> 18 #include <asm/mshyperv.h> 19 #include <linux/atomic.h> 20 #include <linux/hyperv.h> 21 #include <linux/interrupt.h> 22 #include <hyperv/hvhdk.h> 23 24 #include "hv_trace.h" 25 26 /* 27 * Timeout for services such as KVP and fcopy. 28 */ 29 #define HV_UTIL_TIMEOUT 30 30 31 /* 32 * Timeout for guest-host handshake for services. 33 */ 34 #define HV_UTIL_NEGO_TIMEOUT 55 35 36 void vmbus_isr(void); 37 38 /* Definitions for the monitored notification facility */ 39 union hv_monitor_trigger_group { 40 u64 as_uint64; 41 struct { 42 u32 pending; 43 u32 armed; 44 }; 45 }; 46 47 struct hv_monitor_parameter { 48 union hv_connection_id connectionid; 49 u16 flagnumber; 50 u16 rsvdz; 51 }; 52 53 union hv_monitor_trigger_state { 54 u32 asu32; 55 56 struct { 57 u32 group_enable:4; 58 u32 rsvdz:28; 59 }; 60 }; 61 62 /* struct hv_monitor_page Layout */ 63 /* ------------------------------------------------------ */ 64 /* | 0 | TriggerState (4 bytes) | Rsvd1 (4 bytes) | */ 65 /* | 8 | TriggerGroup[0] | */ 66 /* | 10 | TriggerGroup[1] | */ 67 /* | 18 | TriggerGroup[2] | */ 68 /* | 20 | TriggerGroup[3] | */ 69 /* | 28 | Rsvd2[0] | */ 70 /* | 30 | Rsvd2[1] | */ 71 /* | 38 | Rsvd2[2] | */ 72 /* | 40 | NextCheckTime[0][0] | NextCheckTime[0][1] | */ 73 /* | ... | */ 74 /* | 240 | Latency[0][0..3] | */ 75 /* | 340 | Rsvz3[0] | */ 76 /* | 440 | Parameter[0][0] | */ 77 /* | 448 | Parameter[0][1] | */ 78 /* | ... | */ 79 /* | 840 | Rsvd4[0] | */ 80 /* ------------------------------------------------------ */ 81 struct hv_monitor_page { 82 union hv_monitor_trigger_state trigger_state; 83 u32 rsvdz1; 84 85 union hv_monitor_trigger_group trigger_group[4]; 86 u64 rsvdz2[3]; 87 88 s32 next_checktime[4][32]; 89 90 u16 latency[4][32]; 91 u64 rsvdz3[32]; 92 93 struct hv_monitor_parameter parameter[4][32]; 94 95 u8 rsvdz4[1984]; 96 }; 97 98 #define HV_HYPERCALL_PARAM_ALIGN sizeof(u64) 99 100 /* Definition of the hv_post_message hypercall input structure. */ 101 struct hv_input_post_message { 102 union hv_connection_id connectionid; 103 u32 reserved; 104 u32 message_type; 105 u32 payload_size; 106 u64 payload[HV_MESSAGE_PAYLOAD_QWORD_COUNT]; 107 }; 108 109 110 enum { 111 VMBUS_MESSAGE_CONNECTION_ID = 1, 112 VMBUS_MESSAGE_CONNECTION_ID_4 = 4, 113 VMBUS_MESSAGE_PORT_ID = 1, 114 VMBUS_EVENT_CONNECTION_ID = 2, 115 VMBUS_EVENT_PORT_ID = 2, 116 VMBUS_MONITOR_CONNECTION_ID = 3, 117 VMBUS_MONITOR_PORT_ID = 3, 118 VMBUS_MESSAGE_SINT = 2, 119 }; 120 121 /* 122 * Per cpu state for channel handling 123 */ 124 struct hv_per_cpu_context { 125 /* 126 * SynIC pages for communicating with the host. 127 * 128 * These pages are accessible to the host partition and the hypervisor. 129 * They may be used for exchanging data with the host partition and the 130 * hypervisor even when they aren't trusted yet the guest partition 131 * must be prepared to handle the malicious behavior. 132 */ 133 void *hyp_synic_message_page; 134 void *hyp_synic_event_page; 135 /* 136 * SynIC pages for communicating with the paravisor. 137 * 138 * These pages may be accessed from within the guest partition only in 139 * CoCo VMs. Neither the host partition nor the hypervisor can access 140 * these pages in that case; they are used for exchanging data with the 141 * paravisor. 142 */ 143 void *para_synic_message_page; 144 void *para_synic_event_page; 145 146 /* 147 * The page is only used in hv_post_message() for a TDX VM (with the 148 * paravisor) to post a messages to Hyper-V: when such a VM calls 149 * HVCALL_POST_MESSAGE, it can't use the hyperv_pcpu_input_arg (which 150 * is encrypted in such a VM) as the hypercall input page, because 151 * the input page for HVCALL_POST_MESSAGE must be decrypted in such a 152 * VM, so post_msg_page (which is decrypted in hv_synic_alloc()) is 153 * introduced for this purpose. See hyperv_init() for more comments. 154 */ 155 void *post_msg_page; 156 157 /* 158 * Starting with win8, we can take channel interrupts on any CPU; 159 * we will manage the tasklet that handles events messages on a per CPU 160 * basis. 161 */ 162 struct tasklet_struct msg_dpc; 163 }; 164 165 struct hv_context { 166 /* We only support running on top of Hyper-V 167 * So at this point this really can only contain the Hyper-V ID 168 */ 169 u64 guestid; 170 171 struct hv_per_cpu_context __percpu *cpu_context; 172 173 /* 174 * To manage allocations in a NUMA node. 175 * Array indexed by numa node ID. 176 */ 177 struct cpumask *hv_numa_map; 178 }; 179 180 extern struct hv_context hv_context; 181 182 /* Hv Interface */ 183 184 extern int hv_init(void); 185 186 extern int hv_post_message(union hv_connection_id connection_id, 187 enum hv_message_type message_type, 188 void *payload, size_t payload_size); 189 190 extern int hv_synic_alloc(void); 191 192 extern void hv_synic_free(void); 193 194 extern void hv_hyp_synic_enable_regs(unsigned int cpu); 195 extern int hv_synic_init(unsigned int cpu); 196 197 extern void hv_hyp_synic_disable_regs(unsigned int cpu); 198 extern int hv_synic_cleanup(unsigned int cpu); 199 200 /* Interface */ 201 202 void hv_ringbuffer_pre_init(struct vmbus_channel *channel); 203 204 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, 205 struct page *pages, u32 pagecnt, u32 max_pkt_size, 206 bool confidential); 207 208 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info); 209 210 int hv_ringbuffer_write(struct vmbus_channel *channel, 211 const struct kvec *kv_list, u32 kv_count, 212 u64 requestid, u64 *trans_id); 213 214 int hv_ringbuffer_read(struct vmbus_channel *channel, 215 void *buffer, u32 buflen, u32 *buffer_actual_len, 216 u64 *requestid, bool raw); 217 218 /* 219 * The Maximum number of channels (16384) is determined by the size of the 220 * interrupt page, which is HV_HYP_PAGE_SIZE. 1/2 of HV_HYP_PAGE_SIZE is to 221 * send endpoint interrupts, and the other is to receive endpoint interrupts. 222 */ 223 #define MAX_NUM_CHANNELS ((HV_HYP_PAGE_SIZE >> 1) << 3) 224 225 /* The value here must be in multiple of 32 */ 226 #define MAX_NUM_CHANNELS_SUPPORTED 256 227 228 #define MAX_CHANNEL_RELIDS \ 229 max(MAX_NUM_CHANNELS_SUPPORTED, HV_EVENT_FLAGS_COUNT) 230 231 enum vmbus_connect_state { 232 DISCONNECTED, 233 CONNECTING, 234 CONNECTED, 235 DISCONNECTING 236 }; 237 238 #define MAX_SIZE_CHANNEL_MESSAGE HV_MESSAGE_PAYLOAD_BYTE_COUNT 239 240 /* 241 * The CPU that Hyper-V will interrupt for VMBUS messages, such as 242 * CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER. 243 */ 244 #define VMBUS_CONNECT_CPU 0 245 246 struct vmbus_connection { 247 u32 msg_conn_id; 248 249 atomic_t offer_in_progress; 250 251 enum vmbus_connect_state conn_state; 252 253 atomic_t next_gpadl_handle; 254 255 struct completion unload_event; 256 /* 257 * Represents channel interrupts. Each bit position represents a 258 * channel. When a channel sends an interrupt via VMBUS, it finds its 259 * bit in the sendInterruptPage, set it and calls Hv to generate a port 260 * event. The other end receives the port event and parse the 261 * recvInterruptPage to see which bit is set 262 */ 263 void *int_page; 264 void *send_int_page; 265 void *recv_int_page; 266 267 /* 268 * 2 pages - 1st page for parent->child notification and 2nd 269 * is child->parent notification 270 */ 271 struct hv_monitor_page *monitor_pages[2]; 272 struct list_head chn_msg_list; 273 spinlock_t channelmsg_lock; 274 275 /* List of channels */ 276 struct list_head chn_list; 277 struct mutex channel_mutex; 278 279 /* Array of channel pointers, indexed by relid */ 280 struct vmbus_channel **channels; 281 u32 relid_hiwater; 282 283 /* 284 * An offer message is handled first on the work_queue, and then 285 * is further handled on handle_primary_chan_wq or 286 * handle_sub_chan_wq. 287 */ 288 struct workqueue_struct *work_queue; 289 struct workqueue_struct *handle_primary_chan_wq; 290 struct workqueue_struct *handle_sub_chan_wq; 291 struct workqueue_struct *rescind_work_queue; 292 293 /* 294 * On suspension of the vmbus, the accumulated offer messages 295 * must be dropped. 296 */ 297 bool ignore_any_offer_msg; 298 299 /* 300 * The number of sub-channels and hv_sock channels that should be 301 * cleaned up upon suspend: sub-channels will be re-created upon 302 * resume, and hv_sock channels should not survive suspend. 303 */ 304 atomic_t nr_chan_close_on_suspend; 305 /* 306 * vmbus_bus_suspend() waits for "nr_chan_close_on_suspend" to 307 * drop to zero. 308 */ 309 struct completion ready_for_suspend_event; 310 311 /* 312 * Completed once the host has offered all boot-time channels. 313 * Note that some channels may still be under process on a workqueue. 314 */ 315 struct completion all_offers_delivered_event; 316 }; 317 318 319 struct vmbus_msginfo { 320 /* Bookkeeping stuff */ 321 struct list_head msglist_entry; 322 323 /* The message itself */ 324 unsigned char msg[]; 325 }; 326 327 328 extern struct vmbus_connection vmbus_connection; 329 330 int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version); 331 332 static inline void vmbus_send_interrupt(u32 relid) 333 { 334 sync_set_bit(relid, vmbus_connection.send_int_page); 335 } 336 337 enum vmbus_message_handler_type { 338 /* The related handler can sleep. */ 339 VMHT_BLOCKING = 0, 340 341 /* The related handler must NOT sleep. */ 342 VMHT_NON_BLOCKING = 1, 343 }; 344 345 struct vmbus_channel_message_table_entry { 346 enum vmbus_channel_message_type message_type; 347 enum vmbus_message_handler_type handler_type; 348 void (*message_handler)(struct vmbus_channel_message_header *msg); 349 u32 min_payload_len; 350 }; 351 352 extern const struct vmbus_channel_message_table_entry 353 channel_message_table[CHANNELMSG_COUNT]; 354 355 356 /* General vmbus interface */ 357 358 bool vmbus_is_confidential(void); 359 360 #if IS_ENABLED(CONFIG_HYPERV_VMBUS) 361 /* Free the message slot and signal end-of-message if required */ 362 static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) 363 { 364 /* 365 * On crash we're reading some other CPU's message page and we need 366 * to be careful: this other CPU may already had cleared the header 367 * and the host may already had delivered some other message there. 368 * In case we blindly write msg->header.message_type we're going 369 * to lose it. We can still lose a message of the same type but 370 * we count on the fact that there can only be one 371 * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages 372 * on crash. 373 */ 374 if (!try_cmpxchg(&msg->header.message_type, 375 &old_msg_type, HVMSG_NONE)) 376 return; 377 378 /* 379 * The cmpxchg() above does an implicit memory barrier to 380 * ensure the write to MessageType (ie set to 381 * HVMSG_NONE) happens before we read the 382 * MessagePending and EOMing. Otherwise, the EOMing 383 * will not deliver any more messages since there is 384 * no empty slot 385 */ 386 if (msg->header.message_flags.msg_pending) { 387 /* 388 * This will cause message queue rescan to 389 * possibly deliver another msg from the 390 * hypervisor 391 */ 392 if (vmbus_is_confidential()) 393 hv_para_set_synic_register(HV_MSR_EOM, 0); 394 else 395 hv_set_msr(HV_MSR_EOM, 0); 396 } 397 } 398 399 extern int vmbus_interrupt; 400 extern int vmbus_irq; 401 #endif /* CONFIG_HYPERV_VMBUS */ 402 403 struct hv_device *vmbus_device_create(const guid_t *type, 404 const guid_t *instance, 405 struct vmbus_channel *channel); 406 407 int vmbus_device_register(struct hv_device *child_device_obj); 408 void vmbus_device_unregister(struct hv_device *device_obj); 409 int vmbus_add_channel_kobj(struct hv_device *device_obj, 410 struct vmbus_channel *channel); 411 412 void vmbus_remove_channel_attr_group(struct vmbus_channel *channel); 413 414 void vmbus_channel_map_relid(struct vmbus_channel *channel); 415 void vmbus_channel_unmap_relid(struct vmbus_channel *channel); 416 417 struct vmbus_channel *relid2channel(u32 relid); 418 419 void vmbus_free_channels(void); 420 421 /* Connection interface */ 422 423 int vmbus_connect(void); 424 void vmbus_disconnect(void); 425 426 int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep); 427 428 void vmbus_on_event(unsigned long data); 429 void vmbus_on_msg_dpc(unsigned long data); 430 431 int hv_kvp_init(struct hv_util_service *srv); 432 int hv_kvp_init_transport(void); 433 void hv_kvp_deinit(void); 434 int hv_kvp_pre_suspend(void); 435 int hv_kvp_pre_resume(void); 436 void hv_kvp_onchannelcallback(void *context); 437 438 int hv_vss_init(struct hv_util_service *srv); 439 int hv_vss_init_transport(void); 440 void hv_vss_deinit(void); 441 int hv_vss_pre_suspend(void); 442 int hv_vss_pre_resume(void); 443 void hv_vss_onchannelcallback(void *context); 444 void vmbus_initiate_unload(bool crash); 445 446 static inline void hv_poll_channel(struct vmbus_channel *channel, 447 void (*cb)(void *)) 448 { 449 if (!channel) 450 return; 451 cb(channel); 452 } 453 454 enum hvutil_device_state { 455 HVUTIL_DEVICE_INIT = 0, /* driver is loaded, waiting for userspace */ 456 HVUTIL_READY, /* userspace is registered */ 457 HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */ 458 HVUTIL_USERSPACE_REQ, /* request to userspace was sent */ 459 HVUTIL_USERSPACE_RECV, /* reply from userspace was received */ 460 HVUTIL_DEVICE_DYING, /* driver unload is in progress */ 461 }; 462 463 enum delay { 464 INTERRUPT_DELAY = 0, 465 MESSAGE_DELAY = 1, 466 }; 467 468 extern const struct vmbus_device vmbus_devs[]; 469 470 static inline bool hv_is_perf_channel(struct vmbus_channel *channel) 471 { 472 return vmbus_devs[channel->device_id].perf_device; 473 } 474 475 static inline size_t hv_dev_ring_size(struct vmbus_channel *channel) 476 { 477 return vmbus_devs[channel->device_id].pref_ring_size; 478 } 479 480 static inline bool hv_is_allocated_cpu(unsigned int cpu) 481 { 482 struct vmbus_channel *channel, *sc; 483 484 lockdep_assert_held(&vmbus_connection.channel_mutex); 485 /* 486 * List additions/deletions as well as updates of the target CPUs are 487 * protected by channel_mutex. 488 */ 489 list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { 490 if (!hv_is_perf_channel(channel)) 491 continue; 492 if (channel->target_cpu == cpu) 493 return true; 494 list_for_each_entry(sc, &channel->sc_list, sc_list) { 495 if (sc->target_cpu == cpu) 496 return true; 497 } 498 } 499 return false; 500 } 501 502 static inline void hv_set_allocated_cpu(unsigned int cpu) 503 { 504 cpumask_set_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]); 505 } 506 507 static inline void hv_clear_allocated_cpu(unsigned int cpu) 508 { 509 if (hv_is_allocated_cpu(cpu)) 510 return; 511 cpumask_clear_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]); 512 } 513 514 static inline void hv_update_allocated_cpus(unsigned int old_cpu, 515 unsigned int new_cpu) 516 { 517 hv_set_allocated_cpu(new_cpu); 518 hv_clear_allocated_cpu(old_cpu); 519 } 520 521 #ifdef CONFIG_HYPERV_TESTING 522 523 int hv_debug_add_dev_dir(struct hv_device *dev); 524 void hv_debug_rm_dev_dir(struct hv_device *dev); 525 void hv_debug_rm_all_dir(void); 526 int hv_debug_init(void); 527 void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type); 528 529 #else /* CONFIG_HYPERV_TESTING */ 530 531 static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {}; 532 static inline void hv_debug_rm_all_dir(void) {}; 533 static inline void hv_debug_delay_test(struct vmbus_channel *channel, 534 enum delay delay_type) {}; 535 static inline int hv_debug_init(void) 536 { 537 return -1; 538 } 539 540 static inline int hv_debug_add_dev_dir(struct hv_device *dev) 541 { 542 return -1; 543 } 544 545 #endif /* CONFIG_HYPERV_TESTING */ 546 547 /* Create and remove sysfs entry for memory mapped ring buffers for a channel */ 548 int hv_create_ring_sysfs(struct vmbus_channel *channel, 549 int (*hv_mmap_prepare_ring_buffer)(struct vmbus_channel *channel, 550 struct vm_area_desc *desc)); 551 int hv_remove_ring_sysfs(struct vmbus_channel *channel); 552 553 #endif /* _HYPERV_VMBUS_H */ 554