xref: /linux/drivers/hv/hyperv_vmbus.h (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 struct hv_context {
138 	/* We only support running on top of Hyper-V
139 	 * So at this point this really can only contain the Hyper-V ID
140 	 */
141 	u64 guestid;
142 
143 	struct hv_per_cpu_context __percpu *cpu_context;
144 
145 	/*
146 	 * To manage allocations in a NUMA node.
147 	 * Array indexed by numa node ID.
148 	 */
149 	struct cpumask *hv_numa_map;
150 };
151 
152 extern struct hv_context hv_context;
153 
154 /* Hv Interface */
155 
156 extern int hv_init(void);
157 
158 extern int hv_post_message(union hv_connection_id connection_id,
159 			 enum hv_message_type message_type,
160 			 void *payload, size_t payload_size);
161 
162 extern int hv_synic_alloc(void);
163 
164 extern void hv_synic_free(void);
165 
166 extern void hv_synic_enable_regs(unsigned int cpu);
167 extern int hv_synic_init(unsigned int cpu);
168 
169 extern void hv_synic_disable_regs(unsigned int cpu);
170 extern int hv_synic_cleanup(unsigned int cpu);
171 
172 /* Interface */
173 
174 void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
175 
176 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
177 		       struct page *pages, u32 pagecnt);
178 
179 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
180 
181 int hv_ringbuffer_write(struct vmbus_channel *channel,
182 			const struct kvec *kv_list, u32 kv_count,
183 			u64 requestid);
184 
185 int hv_ringbuffer_read(struct vmbus_channel *channel,
186 		       void *buffer, u32 buflen, u32 *buffer_actual_len,
187 		       u64 *requestid, bool raw);
188 
189 /*
190  * The Maximum number of channels (16384) is determined by the size of the
191  * interrupt page, which is HV_HYP_PAGE_SIZE. 1/2 of HV_HYP_PAGE_SIZE is to
192  * send endpoint interrupts, and the other is to receive endpoint interrupts.
193  */
194 #define MAX_NUM_CHANNELS	((HV_HYP_PAGE_SIZE >> 1) << 3)
195 
196 /* The value here must be in multiple of 32 */
197 #define MAX_NUM_CHANNELS_SUPPORTED	256
198 
199 #define MAX_CHANNEL_RELIDS					\
200 	max(MAX_NUM_CHANNELS_SUPPORTED, HV_EVENT_FLAGS_COUNT)
201 
202 enum vmbus_connect_state {
203 	DISCONNECTED,
204 	CONNECTING,
205 	CONNECTED,
206 	DISCONNECTING
207 };
208 
209 #define MAX_SIZE_CHANNEL_MESSAGE	HV_MESSAGE_PAYLOAD_BYTE_COUNT
210 
211 /*
212  * The CPU that Hyper-V will interrupt for VMBUS messages, such as
213  * CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER.
214  */
215 #define VMBUS_CONNECT_CPU	0
216 
217 struct vmbus_connection {
218 	u32 msg_conn_id;
219 
220 	atomic_t offer_in_progress;
221 
222 	enum vmbus_connect_state conn_state;
223 
224 	atomic_t next_gpadl_handle;
225 
226 	struct completion  unload_event;
227 	/*
228 	 * Represents channel interrupts. Each bit position represents a
229 	 * channel.  When a channel sends an interrupt via VMBUS, it finds its
230 	 * bit in the sendInterruptPage, set it and calls Hv to generate a port
231 	 * event. The other end receives the port event and parse the
232 	 * recvInterruptPage to see which bit is set
233 	 */
234 	void *int_page;
235 	void *send_int_page;
236 	void *recv_int_page;
237 
238 	/*
239 	 * 2 pages - 1st page for parent->child notification and 2nd
240 	 * is child->parent notification
241 	 */
242 	struct hv_monitor_page *monitor_pages[2];
243 	struct list_head chn_msg_list;
244 	spinlock_t channelmsg_lock;
245 
246 	/* List of channels */
247 	struct list_head chn_list;
248 	struct mutex channel_mutex;
249 
250 	/* Array of channels */
251 	struct vmbus_channel **channels;
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[];
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 	u32 min_payload_len;
321 };
322 
323 extern const struct vmbus_channel_message_table_entry
324 	channel_message_table[CHANNELMSG_COUNT];
325 
326 
327 /* General vmbus interface */
328 
329 struct hv_device *vmbus_device_create(const guid_t *type,
330 				      const guid_t *instance,
331 				      struct vmbus_channel *channel);
332 
333 int vmbus_device_register(struct hv_device *child_device_obj);
334 void vmbus_device_unregister(struct hv_device *device_obj);
335 int vmbus_add_channel_kobj(struct hv_device *device_obj,
336 			   struct vmbus_channel *channel);
337 
338 void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
339 
340 void vmbus_channel_map_relid(struct vmbus_channel *channel);
341 void vmbus_channel_unmap_relid(struct vmbus_channel *channel);
342 
343 struct vmbus_channel *relid2channel(u32 relid);
344 
345 void vmbus_free_channels(void);
346 
347 /* Connection interface */
348 
349 int vmbus_connect(void);
350 void vmbus_disconnect(void);
351 
352 int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
353 
354 void vmbus_on_event(unsigned long data);
355 void vmbus_on_msg_dpc(unsigned long data);
356 
357 int hv_kvp_init(struct hv_util_service *srv);
358 void hv_kvp_deinit(void);
359 int hv_kvp_pre_suspend(void);
360 int hv_kvp_pre_resume(void);
361 void hv_kvp_onchannelcallback(void *context);
362 
363 int hv_vss_init(struct hv_util_service *srv);
364 void hv_vss_deinit(void);
365 int hv_vss_pre_suspend(void);
366 int hv_vss_pre_resume(void);
367 void hv_vss_onchannelcallback(void *context);
368 
369 int hv_fcopy_init(struct hv_util_service *srv);
370 void hv_fcopy_deinit(void);
371 int hv_fcopy_pre_suspend(void);
372 int hv_fcopy_pre_resume(void);
373 void hv_fcopy_onchannelcallback(void *context);
374 void vmbus_initiate_unload(bool crash);
375 
376 static inline void hv_poll_channel(struct vmbus_channel *channel,
377 				   void (*cb)(void *))
378 {
379 	if (!channel)
380 		return;
381 	cb(channel);
382 }
383 
384 enum hvutil_device_state {
385 	HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
386 	HVUTIL_READY,            /* userspace is registered */
387 	HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
388 	HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
389 	HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
390 	HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
391 };
392 
393 enum delay {
394 	INTERRUPT_DELAY = 0,
395 	MESSAGE_DELAY   = 1,
396 };
397 
398 extern const struct vmbus_device vmbus_devs[];
399 
400 static inline bool hv_is_perf_channel(struct vmbus_channel *channel)
401 {
402 	return vmbus_devs[channel->device_id].perf_device;
403 }
404 
405 static inline bool hv_is_alloced_cpu(unsigned int cpu)
406 {
407 	struct vmbus_channel *channel, *sc;
408 
409 	lockdep_assert_held(&vmbus_connection.channel_mutex);
410 	/*
411 	 * List additions/deletions as well as updates of the target CPUs are
412 	 * protected by channel_mutex.
413 	 */
414 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
415 		if (!hv_is_perf_channel(channel))
416 			continue;
417 		if (channel->target_cpu == cpu)
418 			return true;
419 		list_for_each_entry(sc, &channel->sc_list, sc_list) {
420 			if (sc->target_cpu == cpu)
421 				return true;
422 		}
423 	}
424 	return false;
425 }
426 
427 static inline void hv_set_alloced_cpu(unsigned int cpu)
428 {
429 	cpumask_set_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
430 }
431 
432 static inline void hv_clear_alloced_cpu(unsigned int cpu)
433 {
434 	if (hv_is_alloced_cpu(cpu))
435 		return;
436 	cpumask_clear_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
437 }
438 
439 static inline void hv_update_alloced_cpus(unsigned int old_cpu,
440 					  unsigned int new_cpu)
441 {
442 	hv_set_alloced_cpu(new_cpu);
443 	hv_clear_alloced_cpu(old_cpu);
444 }
445 
446 #ifdef CONFIG_HYPERV_TESTING
447 
448 int hv_debug_add_dev_dir(struct hv_device *dev);
449 void hv_debug_rm_dev_dir(struct hv_device *dev);
450 void hv_debug_rm_all_dir(void);
451 int hv_debug_init(void);
452 void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
453 
454 #else /* CONFIG_HYPERV_TESTING */
455 
456 static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {};
457 static inline void hv_debug_rm_all_dir(void) {};
458 static inline void hv_debug_delay_test(struct vmbus_channel *channel,
459 				       enum delay delay_type) {};
460 static inline int hv_debug_init(void)
461 {
462 	return -1;
463 }
464 
465 static inline int hv_debug_add_dev_dir(struct hv_device *dev)
466 {
467 	return -1;
468 }
469 
470 #endif /* CONFIG_HYPERV_TESTING */
471 
472 #endif /* _HYPERV_VMBUS_H */
473