root/drivers/hv/hyperv_vmbus.h

INCLUDED FROM

DEFINITIONS

1. vmbus_send_interrupt
2. hv_poll_channel

   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 <asm/sync_bitops.h>
  17 #include <asm/hyperv-tlfs.h>
  18 #include <linux/atomic.h>
  19 #include <linux/hyperv.h>
  20 #include <linux/interrupt.h>
  21 
  22 #include "hv_trace.h"
  23 
  24 /*
  25  * Timeout for services such as KVP and fcopy.
  26  */
  27 #define HV_UTIL_TIMEOUT 30
  28 
  29 /*
  30  * Timeout for guest-host handshake for services.
  31  */
  32 #define HV_UTIL_NEGO_TIMEOUT 55
  33 
  34 
  35 /* Definitions for the monitored notification facility */
  36 union hv_monitor_trigger_group {
  37         u64 as_uint64;
  38         struct {
  39                 u32 pending;
  40                 u32 armed;
  41         };
  42 };
  43 
  44 struct hv_monitor_parameter {
  45         union hv_connection_id connectionid;
  46         u16 flagnumber;
  47         u16 rsvdz;
  48 };
  49 
  50 union hv_monitor_trigger_state {
  51         u32 asu32;
  52 
  53         struct {
  54                 u32 group_enable:4;
  55                 u32 rsvdz:28;
  56         };
  57 };
  58 
  59 /* struct hv_monitor_page Layout */
  60 /* ------------------------------------------------------ */
  61 /* | 0   | TriggerState (4 bytes) | Rsvd1 (4 bytes)     | */
  62 /* | 8   | TriggerGroup[0]                              | */
  63 /* | 10  | TriggerGroup[1]                              | */
  64 /* | 18  | TriggerGroup[2]                              | */
  65 /* | 20  | TriggerGroup[3]                              | */
  66 /* | 28  | Rsvd2[0]                                     | */
  67 /* | 30  | Rsvd2[1]                                     | */
  68 /* | 38  | Rsvd2[2]                                     | */
  69 /* | 40  | NextCheckTime[0][0]    | NextCheckTime[0][1] | */
  70 /* | ...                                                | */
  71 /* | 240 | Latency[0][0..3]                             | */
  72 /* | 340 | Rsvz3[0]                                     | */
  73 /* | 440 | Parameter[0][0]                              | */
  74 /* | 448 | Parameter[0][1]                              | */
  75 /* | ...                                                | */
  76 /* | 840 | Rsvd4[0]                                     | */
  77 /* ------------------------------------------------------ */
  78 struct hv_monitor_page {
  79         union hv_monitor_trigger_state trigger_state;
  80         u32 rsvdz1;
  81 
  82         union hv_monitor_trigger_group trigger_group[4];
  83         u64 rsvdz2[3];
  84 
  85         s32 next_checktime[4][32];
  86 
  87         u16 latency[4][32];
  88         u64 rsvdz3[32];
  89 
  90         struct hv_monitor_parameter parameter[4][32];
  91 
  92         u8 rsvdz4[1984];
  93 };
  94 
  95 #define HV_HYPERCALL_PARAM_ALIGN        sizeof(u64)
  96 
  97 /* Definition of the hv_post_message hypercall input structure. */
  98 struct hv_input_post_message {
  99         union hv_connection_id connectionid;
 100         u32 reserved;
 101         u32 message_type;
 102         u32 payload_size;
 103         u64 payload[HV_MESSAGE_PAYLOAD_QWORD_COUNT];
 104 };
 105 
 106 
 107 enum {
 108         VMBUS_MESSAGE_CONNECTION_ID     = 1,
 109         VMBUS_MESSAGE_CONNECTION_ID_4   = 4,
 110         VMBUS_MESSAGE_PORT_ID           = 1,
 111         VMBUS_EVENT_CONNECTION_ID       = 2,
 112         VMBUS_EVENT_PORT_ID             = 2,
 113         VMBUS_MONITOR_CONNECTION_ID     = 3,
 114         VMBUS_MONITOR_PORT_ID           = 3,
 115         VMBUS_MESSAGE_SINT              = 2,
 116 };
 117 
 118 /*
 119  * Per cpu state for channel handling
 120  */
 121 struct hv_per_cpu_context {
 122         void *synic_message_page;
 123         void *synic_event_page;
 124         /*
 125          * buffer to post messages to the host.
 126          */
 127         void *post_msg_page;
 128 
 129         /*
 130          * Starting with win8, we can take channel interrupts on any CPU;
 131          * we will manage the tasklet that handles events messages on a per CPU
 132          * basis.
 133          */
 134         struct tasklet_struct msg_dpc;
 135 
 136         /*
 137          * To optimize the mapping of relid to channel, maintain
 138          * per-cpu list of the channels based on their CPU affinity.
 139          */
 140         struct list_head chan_list;
 141 };
 142 
 143 struct hv_context {
 144         /* We only support running on top of Hyper-V
 145          * So at this point this really can only contain the Hyper-V ID
 146          */
 147         u64 guestid;
 148 
 149         struct hv_per_cpu_context __percpu *cpu_context;
 150 
 151         /*
 152          * To manage allocations in a NUMA node.
 153          * Array indexed by numa node ID.
 154          */
 155         struct cpumask *hv_numa_map;
 156 };
 157 
 158 extern struct hv_context hv_context;
 159 
 160 /* Hv Interface */
 161 
 162 extern int hv_init(void);
 163 
 164 extern int hv_post_message(union hv_connection_id connection_id,
 165                          enum hv_message_type message_type,
 166                          void *payload, size_t payload_size);
 167 
 168 extern int hv_synic_alloc(void);
 169 
 170 extern void hv_synic_free(void);
 171 
 172 extern void hv_synic_enable_regs(unsigned int cpu);
 173 extern int hv_synic_init(unsigned int cpu);
 174 
 175 extern void hv_synic_disable_regs(unsigned int cpu);
 176 extern int hv_synic_cleanup(unsigned int cpu);
 177 
 178 /* Interface */
 179 
 180 void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
 181 
 182 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
 183                        struct page *pages, u32 pagecnt);
 184 
 185 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
 186 
 187 int hv_ringbuffer_write(struct vmbus_channel *channel,
 188                         const struct kvec *kv_list, u32 kv_count);
 189 
 190 int hv_ringbuffer_read(struct vmbus_channel *channel,
 191                        void *buffer, u32 buflen, u32 *buffer_actual_len,
 192                        u64 *requestid, bool raw);
 193 
 194 /*
 195  * The Maximum number of channels (16348) is determined by the size of the
 196  * interrupt page, which is HV_HYP_PAGE_SIZE. 1/2 of HV_HYP_PAGE_SIZE is to
 197  * send endpoint interrupts, and the other is to receive endpoint interrupts.
 198  */
 199 #define MAX_NUM_CHANNELS        ((HV_HYP_PAGE_SIZE >> 1) << 3)
 200 
 201 /* The value here must be in multiple of 32 */
 202 /* TODO: Need to make this configurable */
 203 #define MAX_NUM_CHANNELS_SUPPORTED      256
 204 
 205 
 206 enum vmbus_connect_state {
 207         DISCONNECTED,
 208         CONNECTING,
 209         CONNECTED,
 210         DISCONNECTING
 211 };
 212 
 213 #define MAX_SIZE_CHANNEL_MESSAGE        HV_MESSAGE_PAYLOAD_BYTE_COUNT
 214 
 215 struct vmbus_connection {
 216         /*
 217          * CPU on which the initial host contact was made.
 218          */
 219         int connect_cpu;
 220 
 221         u32 msg_conn_id;
 222 
 223         atomic_t offer_in_progress;
 224 
 225         enum vmbus_connect_state conn_state;
 226 
 227         atomic_t next_gpadl_handle;
 228 
 229         struct completion  unload_event;
 230         /*
 231          * Represents channel interrupts. Each bit position represents a
 232          * channel.  When a channel sends an interrupt via VMBUS, it finds its
 233          * bit in the sendInterruptPage, set it and calls Hv to generate a port
 234          * event. The other end receives the port event and parse the
 235          * recvInterruptPage to see which bit is set
 236          */
 237         void *int_page;
 238         void *send_int_page;
 239         void *recv_int_page;
 240 
 241         /*
 242          * 2 pages - 1st page for parent->child notification and 2nd
 243          * is child->parent notification
 244          */
 245         struct hv_monitor_page *monitor_pages[2];
 246         struct list_head chn_msg_list;
 247         spinlock_t channelmsg_lock;
 248 
 249         /* List of channels */
 250         struct list_head chn_list;
 251         struct mutex channel_mutex;
 252 
 253         /*
 254          * An offer message is handled first on the work_queue, and then
 255          * is further handled on handle_primary_chan_wq or
 256          * handle_sub_chan_wq.
 257          */
 258         struct workqueue_struct *work_queue;
 259         struct workqueue_struct *handle_primary_chan_wq;
 260         struct workqueue_struct *handle_sub_chan_wq;
 261 
 262         /*
 263          * The number of sub-channels and hv_sock channels that should be
 264          * cleaned up upon suspend: sub-channels will be re-created upon
 265          * resume, and hv_sock channels should not survive suspend.
 266          */
 267         atomic_t nr_chan_close_on_suspend;
 268         /*
 269          * vmbus_bus_suspend() waits for "nr_chan_close_on_suspend" to
 270          * drop to zero.
 271          */
 272         struct completion ready_for_suspend_event;
 273 
 274         /*
 275          * The number of primary channels that should be "fixed up"
 276          * upon resume: these channels are re-offered upon resume, and some
 277          * fields of the channel offers (i.e. child_relid and connection_id)
 278          * can change, so the old offermsg must be fixed up, before the resume
 279          * callbacks of the VSC drivers start to further touch the channels.
 280          */
 281         atomic_t nr_chan_fixup_on_resume;
 282         /*
 283          * vmbus_bus_resume() waits for "nr_chan_fixup_on_resume" to
 284          * drop to zero.
 285          */
 286         struct completion ready_for_resume_event;
 287 };
 288 
 289 
 290 struct vmbus_msginfo {
 291         /* Bookkeeping stuff */
 292         struct list_head msglist_entry;
 293 
 294         /* The message itself */
 295         unsigned char msg[0];
 296 };
 297 
 298 
 299 extern struct vmbus_connection vmbus_connection;
 300 
 301 int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version);
 302 
 303 static inline void vmbus_send_interrupt(u32 relid)
 304 {
 305         sync_set_bit(relid, vmbus_connection.send_int_page);
 306 }
 307 
 308 enum vmbus_message_handler_type {
 309         /* The related handler can sleep. */
 310         VMHT_BLOCKING = 0,
 311 
 312         /* The related handler must NOT sleep. */
 313         VMHT_NON_BLOCKING = 1,
 314 };
 315 
 316 struct vmbus_channel_message_table_entry {
 317         enum vmbus_channel_message_type message_type;
 318         enum vmbus_message_handler_type handler_type;
 319         void (*message_handler)(struct vmbus_channel_message_header *msg);
 320 };
 321 
 322 extern const struct vmbus_channel_message_table_entry
 323         channel_message_table[CHANNELMSG_COUNT];
 324 
 325 
 326 /* General vmbus interface */
 327 
 328 struct hv_device *vmbus_device_create(const guid_t *type,
 329                                       const guid_t *instance,
 330                                       struct vmbus_channel *channel);
 331 
 332 int vmbus_device_register(struct hv_device *child_device_obj);
 333 void vmbus_device_unregister(struct hv_device *device_obj);
 334 int vmbus_add_channel_kobj(struct hv_device *device_obj,
 335                            struct vmbus_channel *channel);
 336 
 337 void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
 338 
 339 struct vmbus_channel *relid2channel(u32 relid);
 340 
 341 void vmbus_free_channels(void);
 342 
 343 /* Connection interface */
 344 
 345 int vmbus_connect(void);
 346 void vmbus_disconnect(void);
 347 
 348 int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
 349 
 350 void vmbus_on_event(unsigned long data);
 351 void vmbus_on_msg_dpc(unsigned long data);
 352 
 353 int hv_kvp_init(struct hv_util_service *srv);
 354 void hv_kvp_deinit(void);
 355 void hv_kvp_onchannelcallback(void *context);
 356 
 357 int hv_vss_init(struct hv_util_service *srv);
 358 void hv_vss_deinit(void);
 359 void hv_vss_onchannelcallback(void *context);
 360 
 361 int hv_fcopy_init(struct hv_util_service *srv);
 362 void hv_fcopy_deinit(void);
 363 void hv_fcopy_onchannelcallback(void *context);
 364 void vmbus_initiate_unload(bool crash);
 365 
 366 static inline void hv_poll_channel(struct vmbus_channel *channel,
 367                                    void (*cb)(void *))
 368 {
 369         if (!channel)
 370                 return;
 371 
 372         if (in_interrupt() && (channel->target_cpu == smp_processor_id())) {
 373                 cb(channel);
 374                 return;
 375         }
 376         smp_call_function_single(channel->target_cpu, cb, channel, true);
 377 }
 378 
 379 enum hvutil_device_state {
 380         HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
 381         HVUTIL_READY,            /* userspace is registered */
 382         HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
 383         HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
 384         HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
 385         HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
 386 };
 387 
 388 #endif /* _HYPERV_VMBUS_H */