xref: /linux/drivers/hv/hyperv_vmbus.h (revision f898c16a0624e7f2dcb0b1cda6916c9be6489197)
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 
384 int hv_fcopy_init(struct hv_util_service *srv);
385 void hv_fcopy_deinit(void);
386 int hv_fcopy_pre_suspend(void);
387 int hv_fcopy_pre_resume(void);
388 void hv_fcopy_onchannelcallback(void *context);
389 void vmbus_initiate_unload(bool crash);
390 
391 static inline void hv_poll_channel(struct vmbus_channel *channel,
392 				   void (*cb)(void *))
393 {
394 	if (!channel)
395 		return;
396 	cb(channel);
397 }
398 
399 enum hvutil_device_state {
400 	HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
401 	HVUTIL_READY,            /* userspace is registered */
402 	HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
403 	HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
404 	HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
405 	HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
406 };
407 
408 enum delay {
409 	INTERRUPT_DELAY = 0,
410 	MESSAGE_DELAY   = 1,
411 };
412 
413 extern const struct vmbus_device vmbus_devs[];
414 
415 static inline bool hv_is_perf_channel(struct vmbus_channel *channel)
416 {
417 	return vmbus_devs[channel->device_id].perf_device;
418 }
419 
420 static inline size_t hv_dev_ring_size(struct vmbus_channel *channel)
421 {
422 	return vmbus_devs[channel->device_id].pref_ring_size;
423 }
424 
425 static inline bool hv_is_allocated_cpu(unsigned int cpu)
426 {
427 	struct vmbus_channel *channel, *sc;
428 
429 	lockdep_assert_held(&vmbus_connection.channel_mutex);
430 	/*
431 	 * List additions/deletions as well as updates of the target CPUs are
432 	 * protected by channel_mutex.
433 	 */
434 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
435 		if (!hv_is_perf_channel(channel))
436 			continue;
437 		if (channel->target_cpu == cpu)
438 			return true;
439 		list_for_each_entry(sc, &channel->sc_list, sc_list) {
440 			if (sc->target_cpu == cpu)
441 				return true;
442 		}
443 	}
444 	return false;
445 }
446 
447 static inline void hv_set_allocated_cpu(unsigned int cpu)
448 {
449 	cpumask_set_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
450 }
451 
452 static inline void hv_clear_allocated_cpu(unsigned int cpu)
453 {
454 	if (hv_is_allocated_cpu(cpu))
455 		return;
456 	cpumask_clear_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
457 }
458 
459 static inline void hv_update_allocated_cpus(unsigned int old_cpu,
460 					  unsigned int new_cpu)
461 {
462 	hv_set_allocated_cpu(new_cpu);
463 	hv_clear_allocated_cpu(old_cpu);
464 }
465 
466 #ifdef CONFIG_HYPERV_TESTING
467 
468 int hv_debug_add_dev_dir(struct hv_device *dev);
469 void hv_debug_rm_dev_dir(struct hv_device *dev);
470 void hv_debug_rm_all_dir(void);
471 int hv_debug_init(void);
472 void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
473 
474 #else /* CONFIG_HYPERV_TESTING */
475 
476 static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {};
477 static inline void hv_debug_rm_all_dir(void) {};
478 static inline void hv_debug_delay_test(struct vmbus_channel *channel,
479 				       enum delay delay_type) {};
480 static inline int hv_debug_init(void)
481 {
482 	return -1;
483 }
484 
485 static inline int hv_debug_add_dev_dir(struct hv_device *dev)
486 {
487 	return -1;
488 }
489 
490 #endif /* CONFIG_HYPERV_TESTING */
491 
492 #endif /* _HYPERV_VMBUS_H */
493