drivers/hv/hyperv_vmbus.h

   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/hyperv-tlfs.h>
  19 #include <linux/atomic.h>
  20 #include <linux/hyperv.h>
  21 #include <linux/interrupt.h>
  22
  23 #include "hv_trace.h"
  24
  25 /*
  26  * Timeout for services such as KVP and fcopy.
  27  */
  28 #define HV_UTIL_TIMEOUT 30
  29
  30 /*
  31  * Timeout for guest-host handshake for services.
  32  */
  33 #define HV_UTIL_NEGO_TIMEOUT 55
  34
  35
  36 /* Definitions for the monitored notification facility */
  37 union hv_monitor_trigger_group {
  38         u64 as_uint64;
  39         struct {
  40                 u32 pending;
  41                 u32 armed;
  42         };
  43 };
  44
  45 struct hv_monitor_parameter {
  46         union hv_connection_id connectionid;
  47         u16 flagnumber;
  48         u16 rsvdz;
  49 };
  50
  51 union hv_monitor_trigger_state {
  52         u32 asu32;
  53
  54         struct {
  55                 u32 group_enable:4;
  56                 u32 rsvdz:28;
  57         };
  58 };
  59
  60 /* struct hv_monitor_page Layout */
  61 /* ------------------------------------------------------ */
  62 /* | 0   | TriggerState (4 bytes) | Rsvd1 (4 bytes)     | */
  63 /* | 8   | TriggerGroup[0]                              | */
  64 /* | 10  | TriggerGroup[1]                              | */
  65 /* | 18  | TriggerGroup[2]                              | */
  66 /* | 20  | TriggerGroup[3]                              | */
  67 /* | 28  | Rsvd2[0]                                     | */
  68 /* | 30  | Rsvd2[1]                                     | */
  69 /* | 38  | Rsvd2[2]                                     | */
  70 /* | 40  | NextCheckTime[0][0]    | NextCheckTime[0][1] | */
  71 /* | ...                                                | */
  72 /* | 240 | Latency[0][0..3]                             | */
  73 /* | 340 | Rsvz3[0]                                     | */
  74 /* | 440 | Parameter[0][0]                              | */
  75 /* | 448 | Parameter[0][1]                              | */
  76 /* | ...                                                | */
  77 /* | 840 | Rsvd4[0]                                     | */
  78 /* ------------------------------------------------------ */
  79 struct hv_monitor_page {
  80         union hv_monitor_trigger_state trigger_state;
  81         u32 rsvdz1;
  82
  83         union hv_monitor_trigger_group trigger_group[4];
  84         u64 rsvdz2[3];
  85
  86         s32 next_checktime[4][32];
  87
  88         u16 latency[4][32];
  89         u64 rsvdz3[32];
  90
  91         struct hv_monitor_parameter parameter[4][32];
  92
  93         u8 rsvdz4[1984];
  94 };
  95
  96 #define HV_HYPERCALL_PARAM_ALIGN        sizeof(u64)
  97
  98 /* Definition of the hv_post_message hypercall input structure. */
  99 struct hv_input_post_message {
 100         union hv_connection_id connectionid;
 101         u32 reserved;
 102         u32 message_type;
 103         u32 payload_size;
 104         u64 payload[HV_MESSAGE_PAYLOAD_QWORD_COUNT];
 105 };
 106
 107
 108 enum {
 109         VMBUS_MESSAGE_CONNECTION_ID     = 1,
 110         VMBUS_MESSAGE_CONNECTION_ID_4   = 4,
 111         VMBUS_MESSAGE_PORT_ID           = 1,
 112         VMBUS_EVENT_CONNECTION_ID       = 2,
 113         VMBUS_EVENT_PORT_ID             = 2,
 114         VMBUS_MONITOR_CONNECTION_ID     = 3,
 115         VMBUS_MONITOR_PORT_ID           = 3,
 116         VMBUS_MESSAGE_SINT              = 2,
 117 };
 118
 119 /*
 120  * Per cpu state for channel handling
 121  */
 122 struct hv_per_cpu_context {
 123         void *synic_message_page;
 124         void *synic_event_page;
 125
 126         /*
 127          * The page is only used in hv_post_message() for a TDX VM (with the
 128          * paravisor) to post a messages to Hyper-V: when such a VM calls
 129          * HVCALL_POST_MESSAGE, it can't use the hyperv_pcpu_input_arg (which
 130          * is encrypted in such a VM) as the hypercall input page, because
 131          * the input page for HVCALL_POST_MESSAGE must be decrypted in such a
 132          * VM, so post_msg_page (which is decrypted in hv_synic_alloc()) is
 133          * introduced for this purpose. See hyperv_init() for more comments.
 134          */
 135         void *post_msg_page;
 136
 137         /*
 138          * Starting with win8, we can take channel interrupts on any CPU;
 139          * we will manage the tasklet that handles events messages on a per CPU
 140          * basis.
 141          */
 142         struct tasklet_struct msg_dpc;
 143 };
 144
 145 struct hv_context {
 146         /* We only support running on top of Hyper-V
 147          * So at this point this really can only contain the Hyper-V ID
 148          */
 149         u64 guestid;
 150
 151         struct hv_per_cpu_context __percpu *cpu_context;
 152
 153         /*
 154          * To manage allocations in a NUMA node.
 155          * Array indexed by numa node ID.
 156          */
 157         struct cpumask *hv_numa_map;
 158 };
 159
 160 extern struct hv_context hv_context;
 161
 162 /* Hv Interface */
 163
 164 extern int hv_init(void);
 165
 166 extern int hv_post_message(union hv_connection_id connection_id,
 167                          enum hv_message_type message_type,
 168                          void *payload, size_t payload_size);
 169
 170 extern int hv_synic_alloc(void);
 171
 172 extern void hv_synic_free(void);
 173
 174 extern void hv_synic_enable_regs(unsigned int cpu);
 175 extern int hv_synic_init(unsigned int cpu);
 176
 177 extern void hv_synic_disable_regs(unsigned int cpu);
 178 extern int hv_synic_cleanup(unsigned int cpu);
 179
 180 /* Interface */
 181
 182 void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
 183
 184 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
 185                        struct page *pages, u32 pagecnt, u32 max_pkt_size);
 186
 187 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
 188
 189 int hv_ringbuffer_write(struct vmbus_channel *channel,
 190                         const struct kvec *kv_list, u32 kv_count,
 191                         u64 requestid, u64 *trans_id);
 192
 193 int hv_ringbuffer_read(struct vmbus_channel *channel,
 194                        void *buffer, u32 buflen, u32 *buffer_actual_len,
 195                        u64 *requestid, bool raw);
 196
 197 /*
 198  * The Maximum number of channels (16384) is determined by the size of the
 199  * interrupt page, which is HV_HYP_PAGE_SIZE. 1/2 of HV_HYP_PAGE_SIZE is to
 200  * send endpoint interrupts, and the other is to receive endpoint interrupts.
 201  */
 202 #define MAX_NUM_CHANNELS        ((HV_HYP_PAGE_SIZE >> 1) << 3)
 203
 204 /* The value here must be in multiple of 32 */
 205 #define MAX_NUM_CHANNELS_SUPPORTED      256
 206
 207 #define MAX_CHANNEL_RELIDS                                      \
 208         max(MAX_NUM_CHANNELS_SUPPORTED, HV_EVENT_FLAGS_COUNT)
 209
 210 enum vmbus_connect_state {
 211         DISCONNECTED,
 212         CONNECTING,
 213         CONNECTED,
 214         DISCONNECTING
 215 };
 216
 217 #define MAX_SIZE_CHANNEL_MESSAGE        HV_MESSAGE_PAYLOAD_BYTE_COUNT
 218
 219 /*
 220  * The CPU that Hyper-V will interrupt for VMBUS messages, such as
 221  * CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER.
 222  */
 223 #define VMBUS_CONNECT_CPU       0
 224
 225 struct vmbus_connection {
 226         u32 msg_conn_id;
 227
 228         atomic_t offer_in_progress;
 229
 230         enum vmbus_connect_state conn_state;
 231
 232         atomic_t next_gpadl_handle;
 233
 234         struct completion  unload_event;
 235         /*
 236          * Represents channel interrupts. Each bit position represents a
 237          * channel.  When a channel sends an interrupt via VMBUS, it finds its
 238          * bit in the sendInterruptPage, set it and calls Hv to generate a port
 239          * event. The other end receives the port event and parse the
 240          * recvInterruptPage to see which bit is set
 241          */
 242         void *int_page;
 243         void *send_int_page;
 244         void *recv_int_page;
 245
 246         /*
 247          * 2 pages - 1st page for parent->child notification and 2nd
 248          * is child->parent notification
 249          */
 250         struct hv_monitor_page *monitor_pages[2];
 251         struct list_head chn_msg_list;
 252         spinlock_t channelmsg_lock;
 253
 254         /* List of channels */
 255         struct list_head chn_list;
 256         struct mutex channel_mutex;
 257
 258         /* Array of channels */
 259         struct vmbus_channel **channels;
 260
 261         /*
 262          * An offer message is handled first on the work_queue, and then
 263          * is further handled on handle_primary_chan_wq or
 264          * handle_sub_chan_wq.
 265          */
 266         struct workqueue_struct *work_queue;
 267         struct workqueue_struct *handle_primary_chan_wq;
 268         struct workqueue_struct *handle_sub_chan_wq;
 269         struct workqueue_struct *rescind_work_queue;
 270
 271         /*
 272          * On suspension of the vmbus, the accumulated offer messages
 273          * must be dropped.
 274          */
 275         bool ignore_any_offer_msg;
 276
 277         /*
 278          * The number of sub-channels and hv_sock channels that should be
 279          * cleaned up upon suspend: sub-channels will be re-created upon
 280          * resume, and hv_sock channels should not survive suspend.
 281          */
 282         atomic_t nr_chan_close_on_suspend;
 283         /*
 284          * vmbus_bus_suspend() waits for "nr_chan_close_on_suspend" to
 285          * drop to zero.
 286          */
 287         struct completion ready_for_suspend_event;
 288
 289         /*
 290          * The number of primary channels that should be "fixed up"
 291          * upon resume: these channels are re-offered upon resume, and some
 292          * fields of the channel offers (i.e. child_relid and connection_id)
 293          * can change, so the old offermsg must be fixed up, before the resume
 294          * callbacks of the VSC drivers start to further touch the channels.
 295          */
 296         atomic_t nr_chan_fixup_on_resume;
 297         /*
 298          * vmbus_bus_resume() waits for "nr_chan_fixup_on_resume" to
 299          * drop to zero.
 300          */
 301         struct completion ready_for_resume_event;
 302 };
 303
 304
 305 struct vmbus_msginfo {
 306         /* Bookkeeping stuff */
 307         struct list_head msglist_entry;
 308
 309         /* The message itself */
 310         unsigned char msg[];
 311 };
 312
 313
 314 extern struct vmbus_connection vmbus_connection;
 315
 316 int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version);
 317
 318 static inline void vmbus_send_interrupt(u32 relid)
 319 {
 320         sync_set_bit(relid, vmbus_connection.send_int_page);
 321 }
 322
 323 enum vmbus_message_handler_type {
 324         /* The related handler can sleep. */
 325         VMHT_BLOCKING = 0,
 326
 327         /* The related handler must NOT sleep. */
 328         VMHT_NON_BLOCKING = 1,
 329 };
 330
 331 struct vmbus_channel_message_table_entry {
 332         enum vmbus_channel_message_type message_type;
 333         enum vmbus_message_handler_type handler_type;
 334         void (*message_handler)(struct vmbus_channel_message_header *msg);
 335         u32 min_payload_len;
 336 };
 337
 338 extern const struct vmbus_channel_message_table_entry
 339         channel_message_table[CHANNELMSG_COUNT];
 340
 341
 342 /* General vmbus interface */
 343
 344 struct hv_device *vmbus_device_create(const guid_t *type,
 345                                       const guid_t *instance,
 346                                       struct vmbus_channel *channel);
 347
 348 int vmbus_device_register(struct hv_device *child_device_obj);
 349 void vmbus_device_unregister(struct hv_device *device_obj);
 350 int vmbus_add_channel_kobj(struct hv_device *device_obj,
 351                            struct vmbus_channel *channel);
 352
 353 void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
 354
 355 void vmbus_channel_map_relid(struct vmbus_channel *channel);
 356 void vmbus_channel_unmap_relid(struct vmbus_channel *channel);
 357
 358 struct vmbus_channel *relid2channel(u32 relid);
 359
 360 void vmbus_free_channels(void);
 361
 362 /* Connection interface */
 363
 364 int vmbus_connect(void);
 365 void vmbus_disconnect(void);
 366
 367 int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
 368
 369 void vmbus_on_event(unsigned long data);
 370 void vmbus_on_msg_dpc(unsigned long data);
 371
 372 int hv_kvp_init(struct hv_util_service *srv);
 373 void hv_kvp_deinit(void);
 374 int hv_kvp_pre_suspend(void);
 375 int hv_kvp_pre_resume(void);
 376 void hv_kvp_onchannelcallback(void *context);
 377
 378 int hv_vss_init(struct hv_util_service *srv);
 379 void hv_vss_deinit(void);
 380 int hv_vss_pre_suspend(void);
 381 int hv_vss_pre_resume(void);
 382 void hv_vss_onchannelcallback(void *context);
 383 void vmbus_initiate_unload(bool crash);
 384
 385 static inline void hv_poll_channel(struct vmbus_channel *channel,
 386                                    void (*cb)(void *))
 387 {
 388         if (!channel)
 389                 return;
 390         cb(channel);
 391 }
 392
 393 enum hvutil_device_state {
 394         HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
 395         HVUTIL_READY,            /* userspace is registered */
 396         HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
 397         HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
 398         HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
 399         HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
 400 };
 401
 402 enum delay {
 403         INTERRUPT_DELAY = 0,
 404         MESSAGE_DELAY   = 1,
 405 };
 406
 407 extern const struct vmbus_device vmbus_devs[];
 408
 409 static inline bool hv_is_perf_channel(struct vmbus_channel *channel)
 410 {
 411         return vmbus_devs[channel->device_id].perf_device;
 412 }
 413
 414 static inline size_t hv_dev_ring_size(struct vmbus_channel *channel)
 415 {
 416         return vmbus_devs[channel->device_id].pref_ring_size;
 417 }
 418
 419 static inline bool hv_is_allocated_cpu(unsigned int cpu)
 420 {
 421         struct vmbus_channel *channel, *sc;
 422
 423         lockdep_assert_held(&vmbus_connection.channel_mutex);
 424         /*
 425          * List additions/deletions as well as updates of the target CPUs are
 426          * protected by channel_mutex.
 427          */
 428         list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 429                 if (!hv_is_perf_channel(channel))
 430                         continue;
 431                 if (channel->target_cpu == cpu)
 432                         return true;
 433                 list_for_each_entry(sc, &channel->sc_list, sc_list) {
 434                         if (sc->target_cpu == cpu)
 435                                 return true;
 436                 }
 437         }
 438         return false;
 439 }
 440
 441 static inline void hv_set_allocated_cpu(unsigned int cpu)
 442 {
 443         cpumask_set_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
 444 }
 445
 446 static inline void hv_clear_allocated_cpu(unsigned int cpu)
 447 {
 448         if (hv_is_allocated_cpu(cpu))
 449                 return;
 450         cpumask_clear_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
 451 }
 452
 453 static inline void hv_update_allocated_cpus(unsigned int old_cpu,
 454                                           unsigned int new_cpu)
 455 {
 456         hv_set_allocated_cpu(new_cpu);
 457         hv_clear_allocated_cpu(old_cpu);
 458 }
 459
 460 #ifdef CONFIG_HYPERV_TESTING
 461
 462 int hv_debug_add_dev_dir(struct hv_device *dev);
 463 void hv_debug_rm_dev_dir(struct hv_device *dev);
 464 void hv_debug_rm_all_dir(void);
 465 int hv_debug_init(void);
 466 void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
 467
 468 #else /* CONFIG_HYPERV_TESTING */
 469
 470 static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {};
 471 static inline void hv_debug_rm_all_dir(void) {};
 472 static inline void hv_debug_delay_test(struct vmbus_channel *channel,
 473                                        enum delay delay_type) {};
 474 static inline int hv_debug_init(void)
 475 {
 476         return -1;
 477 }
 478
 479 static inline int hv_debug_add_dev_dir(struct hv_device *dev)
 480 {
 481         return -1;
 482 }
 483
 484 #endif /* CONFIG_HYPERV_TESTING */
 485
 486 #endif /* _HYPERV_VMBUS_H */