xref: /linux/drivers/hv/hyperv_vmbus.h (revision 0da908c291070d89482f6211dbe81d4d43c3f7cb)
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 	 * buffer to post messages to the host.
127 	 */
128 	void *post_msg_page;
129 
130 	/*
131 	 * Starting with win8, we can take channel interrupts on any CPU;
132 	 * we will manage the tasklet that handles events messages on a per CPU
133 	 * basis.
134 	 */
135 	struct tasklet_struct msg_dpc;
136 };
137 
138 struct hv_context {
139 	/* We only support running on top of Hyper-V
140 	 * So at this point this really can only contain the Hyper-V ID
141 	 */
142 	u64 guestid;
143 
144 	struct hv_per_cpu_context __percpu *cpu_context;
145 
146 	/*
147 	 * To manage allocations in a NUMA node.
148 	 * Array indexed by numa node ID.
149 	 */
150 	struct cpumask *hv_numa_map;
151 };
152 
153 extern struct hv_context hv_context;
154 
155 /* Hv Interface */
156 
157 extern int hv_init(void);
158 
159 extern int hv_post_message(union hv_connection_id connection_id,
160 			 enum hv_message_type message_type,
161 			 void *payload, size_t payload_size);
162 
163 extern int hv_synic_alloc(void);
164 
165 extern void hv_synic_free(void);
166 
167 extern void hv_synic_enable_regs(unsigned int cpu);
168 extern int hv_synic_init(unsigned int cpu);
169 
170 extern void hv_synic_disable_regs(unsigned int cpu);
171 extern int hv_synic_cleanup(unsigned int cpu);
172 
173 /* Interface */
174 
175 void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
176 
177 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
178 		       struct page *pages, u32 pagecnt, u32 max_pkt_size);
179 
180 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
181 
182 int hv_ringbuffer_write(struct vmbus_channel *channel,
183 			const struct kvec *kv_list, u32 kv_count,
184 			u64 requestid, u64 *trans_id);
185 
186 int hv_ringbuffer_read(struct vmbus_channel *channel,
187 		       void *buffer, u32 buflen, u32 *buffer_actual_len,
188 		       u64 *requestid, bool raw);
189 
190 /*
191  * The Maximum number of channels (16384) is determined by the size of the
192  * interrupt page, which is HV_HYP_PAGE_SIZE. 1/2 of HV_HYP_PAGE_SIZE is to
193  * send endpoint interrupts, and the other is to receive endpoint interrupts.
194  */
195 #define MAX_NUM_CHANNELS	((HV_HYP_PAGE_SIZE >> 1) << 3)
196 
197 /* The value here must be in multiple of 32 */
198 #define MAX_NUM_CHANNELS_SUPPORTED	256
199 
200 #define MAX_CHANNEL_RELIDS					\
201 	max(MAX_NUM_CHANNELS_SUPPORTED, HV_EVENT_FLAGS_COUNT)
202 
203 enum vmbus_connect_state {
204 	DISCONNECTED,
205 	CONNECTING,
206 	CONNECTED,
207 	DISCONNECTING
208 };
209 
210 #define MAX_SIZE_CHANNEL_MESSAGE	HV_MESSAGE_PAYLOAD_BYTE_COUNT
211 
212 /*
213  * The CPU that Hyper-V will interrupt for VMBUS messages, such as
214  * CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER.
215  */
216 #define VMBUS_CONNECT_CPU	0
217 
218 struct vmbus_connection {
219 	u32 msg_conn_id;
220 
221 	atomic_t offer_in_progress;
222 
223 	enum vmbus_connect_state conn_state;
224 
225 	atomic_t next_gpadl_handle;
226 
227 	struct completion  unload_event;
228 	/*
229 	 * Represents channel interrupts. Each bit position represents a
230 	 * channel.  When a channel sends an interrupt via VMBUS, it finds its
231 	 * bit in the sendInterruptPage, set it and calls Hv to generate a port
232 	 * event. The other end receives the port event and parse the
233 	 * recvInterruptPage to see which bit is set
234 	 */
235 	void *int_page;
236 	void *send_int_page;
237 	void *recv_int_page;
238 
239 	/*
240 	 * 2 pages - 1st page for parent->child notification and 2nd
241 	 * is child->parent notification
242 	 */
243 	struct hv_monitor_page *monitor_pages[2];
244 	void *monitor_pages_original[2];
245 	phys_addr_t monitor_pages_pa[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 	/* Array of channels */
254 	struct vmbus_channel **channels;
255 
256 	/*
257 	 * An offer message is handled first on the work_queue, and then
258 	 * is further handled on handle_primary_chan_wq or
259 	 * handle_sub_chan_wq.
260 	 */
261 	struct workqueue_struct *work_queue;
262 	struct workqueue_struct *handle_primary_chan_wq;
263 	struct workqueue_struct *handle_sub_chan_wq;
264 	struct workqueue_struct *rescind_work_queue;
265 
266 	/*
267 	 * On suspension of the vmbus, the accumulated offer messages
268 	 * must be dropped.
269 	 */
270 	bool ignore_any_offer_msg;
271 
272 	/*
273 	 * The number of sub-channels and hv_sock channels that should be
274 	 * cleaned up upon suspend: sub-channels will be re-created upon
275 	 * resume, and hv_sock channels should not survive suspend.
276 	 */
277 	atomic_t nr_chan_close_on_suspend;
278 	/*
279 	 * vmbus_bus_suspend() waits for "nr_chan_close_on_suspend" to
280 	 * drop to zero.
281 	 */
282 	struct completion ready_for_suspend_event;
283 
284 	/*
285 	 * The number of primary channels that should be "fixed up"
286 	 * upon resume: these channels are re-offered upon resume, and some
287 	 * fields of the channel offers (i.e. child_relid and connection_id)
288 	 * can change, so the old offermsg must be fixed up, before the resume
289 	 * callbacks of the VSC drivers start to further touch the channels.
290 	 */
291 	atomic_t nr_chan_fixup_on_resume;
292 	/*
293 	 * vmbus_bus_resume() waits for "nr_chan_fixup_on_resume" to
294 	 * drop to zero.
295 	 */
296 	struct completion ready_for_resume_event;
297 };
298 
299 
300 struct vmbus_msginfo {
301 	/* Bookkeeping stuff */
302 	struct list_head msglist_entry;
303 
304 	/* The message itself */
305 	unsigned char msg[];
306 };
307 
308 
309 extern struct vmbus_connection vmbus_connection;
310 
311 int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version);
312 
313 static inline void vmbus_send_interrupt(u32 relid)
314 {
315 	sync_set_bit(relid, vmbus_connection.send_int_page);
316 }
317 
318 enum vmbus_message_handler_type {
319 	/* The related handler can sleep. */
320 	VMHT_BLOCKING = 0,
321 
322 	/* The related handler must NOT sleep. */
323 	VMHT_NON_BLOCKING = 1,
324 };
325 
326 struct vmbus_channel_message_table_entry {
327 	enum vmbus_channel_message_type message_type;
328 	enum vmbus_message_handler_type handler_type;
329 	void (*message_handler)(struct vmbus_channel_message_header *msg);
330 	u32 min_payload_len;
331 };
332 
333 extern const struct vmbus_channel_message_table_entry
334 	channel_message_table[CHANNELMSG_COUNT];
335 
336 
337 /* General vmbus interface */
338 
339 struct hv_device *vmbus_device_create(const guid_t *type,
340 				      const guid_t *instance,
341 				      struct vmbus_channel *channel);
342 
343 int vmbus_device_register(struct hv_device *child_device_obj);
344 void vmbus_device_unregister(struct hv_device *device_obj);
345 int vmbus_add_channel_kobj(struct hv_device *device_obj,
346 			   struct vmbus_channel *channel);
347 
348 void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
349 
350 void vmbus_channel_map_relid(struct vmbus_channel *channel);
351 void vmbus_channel_unmap_relid(struct vmbus_channel *channel);
352 
353 struct vmbus_channel *relid2channel(u32 relid);
354 
355 void vmbus_free_channels(void);
356 
357 /* Connection interface */
358 
359 int vmbus_connect(void);
360 void vmbus_disconnect(void);
361 
362 int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
363 
364 void vmbus_on_event(unsigned long data);
365 void vmbus_on_msg_dpc(unsigned long data);
366 
367 int hv_kvp_init(struct hv_util_service *srv);
368 void hv_kvp_deinit(void);
369 int hv_kvp_pre_suspend(void);
370 int hv_kvp_pre_resume(void);
371 void hv_kvp_onchannelcallback(void *context);
372 
373 int hv_vss_init(struct hv_util_service *srv);
374 void hv_vss_deinit(void);
375 int hv_vss_pre_suspend(void);
376 int hv_vss_pre_resume(void);
377 void hv_vss_onchannelcallback(void *context);
378 
379 int hv_fcopy_init(struct hv_util_service *srv);
380 void hv_fcopy_deinit(void);
381 int hv_fcopy_pre_suspend(void);
382 int hv_fcopy_pre_resume(void);
383 void hv_fcopy_onchannelcallback(void *context);
384 void vmbus_initiate_unload(bool crash);
385 
386 static inline void hv_poll_channel(struct vmbus_channel *channel,
387 				   void (*cb)(void *))
388 {
389 	if (!channel)
390 		return;
391 	cb(channel);
392 }
393 
394 enum hvutil_device_state {
395 	HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
396 	HVUTIL_READY,            /* userspace is registered */
397 	HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
398 	HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
399 	HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
400 	HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
401 };
402 
403 enum delay {
404 	INTERRUPT_DELAY = 0,
405 	MESSAGE_DELAY   = 1,
406 };
407 
408 extern const struct vmbus_device vmbus_devs[];
409 
410 static inline bool hv_is_perf_channel(struct vmbus_channel *channel)
411 {
412 	return vmbus_devs[channel->device_id].perf_device;
413 }
414 
415 static inline bool hv_is_allocated_cpu(unsigned int cpu)
416 {
417 	struct vmbus_channel *channel, *sc;
418 
419 	lockdep_assert_held(&vmbus_connection.channel_mutex);
420 	/*
421 	 * List additions/deletions as well as updates of the target CPUs are
422 	 * protected by channel_mutex.
423 	 */
424 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
425 		if (!hv_is_perf_channel(channel))
426 			continue;
427 		if (channel->target_cpu == cpu)
428 			return true;
429 		list_for_each_entry(sc, &channel->sc_list, sc_list) {
430 			if (sc->target_cpu == cpu)
431 				return true;
432 		}
433 	}
434 	return false;
435 }
436 
437 static inline void hv_set_allocated_cpu(unsigned int cpu)
438 {
439 	cpumask_set_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
440 }
441 
442 static inline void hv_clear_allocated_cpu(unsigned int cpu)
443 {
444 	if (hv_is_allocated_cpu(cpu))
445 		return;
446 	cpumask_clear_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
447 }
448 
449 static inline void hv_update_allocated_cpus(unsigned int old_cpu,
450 					  unsigned int new_cpu)
451 {
452 	hv_set_allocated_cpu(new_cpu);
453 	hv_clear_allocated_cpu(old_cpu);
454 }
455 
456 #ifdef CONFIG_HYPERV_TESTING
457 
458 int hv_debug_add_dev_dir(struct hv_device *dev);
459 void hv_debug_rm_dev_dir(struct hv_device *dev);
460 void hv_debug_rm_all_dir(void);
461 int hv_debug_init(void);
462 void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
463 
464 #else /* CONFIG_HYPERV_TESTING */
465 
466 static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {};
467 static inline void hv_debug_rm_all_dir(void) {};
468 static inline void hv_debug_delay_test(struct vmbus_channel *channel,
469 				       enum delay delay_type) {};
470 static inline int hv_debug_init(void)
471 {
472 	return -1;
473 }
474 
475 static inline int hv_debug_add_dev_dir(struct hv_device *dev)
476 {
477 	return -1;
478 }
479 
480 #endif /* CONFIG_HYPERV_TESTING */
481 
482 #endif /* _HYPERV_VMBUS_H */
483