xref: /linux/drivers/hv/hyperv_vmbus.h (revision 8a857c55)
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 /*
216  * The CPU that Hyper-V will interrupt for VMBUS messages, such as
217  * CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER.
218  */
219 #define VMBUS_CONNECT_CPU	0
220 
221 struct vmbus_connection {
222 	u32 msg_conn_id;
223 
224 	atomic_t offer_in_progress;
225 
226 	enum vmbus_connect_state conn_state;
227 
228 	atomic_t next_gpadl_handle;
229 
230 	struct completion  unload_event;
231 	/*
232 	 * Represents channel interrupts. Each bit position represents a
233 	 * channel.  When a channel sends an interrupt via VMBUS, it finds its
234 	 * bit in the sendInterruptPage, set it and calls Hv to generate a port
235 	 * event. The other end receives the port event and parse the
236 	 * recvInterruptPage to see which bit is set
237 	 */
238 	void *int_page;
239 	void *send_int_page;
240 	void *recv_int_page;
241 
242 	/*
243 	 * 2 pages - 1st page for parent->child notification and 2nd
244 	 * is child->parent notification
245 	 */
246 	struct hv_monitor_page *monitor_pages[2];
247 	struct list_head chn_msg_list;
248 	spinlock_t channelmsg_lock;
249 
250 	/* List of channels */
251 	struct list_head chn_list;
252 	struct mutex channel_mutex;
253 
254 	/*
255 	 * An offer message is handled first on the work_queue, and then
256 	 * is further handled on handle_primary_chan_wq or
257 	 * handle_sub_chan_wq.
258 	 */
259 	struct workqueue_struct *work_queue;
260 	struct workqueue_struct *handle_primary_chan_wq;
261 	struct workqueue_struct *handle_sub_chan_wq;
262 
263 	/*
264 	 * The number of sub-channels and hv_sock channels that should be
265 	 * cleaned up upon suspend: sub-channels will be re-created upon
266 	 * resume, and hv_sock channels should not survive suspend.
267 	 */
268 	atomic_t nr_chan_close_on_suspend;
269 	/*
270 	 * vmbus_bus_suspend() waits for "nr_chan_close_on_suspend" to
271 	 * drop to zero.
272 	 */
273 	struct completion ready_for_suspend_event;
274 
275 	/*
276 	 * The number of primary channels that should be "fixed up"
277 	 * upon resume: these channels are re-offered upon resume, and some
278 	 * fields of the channel offers (i.e. child_relid and connection_id)
279 	 * can change, so the old offermsg must be fixed up, before the resume
280 	 * callbacks of the VSC drivers start to further touch the channels.
281 	 */
282 	atomic_t nr_chan_fixup_on_resume;
283 	/*
284 	 * vmbus_bus_resume() waits for "nr_chan_fixup_on_resume" to
285 	 * drop to zero.
286 	 */
287 	struct completion ready_for_resume_event;
288 };
289 
290 
291 struct vmbus_msginfo {
292 	/* Bookkeeping stuff */
293 	struct list_head msglist_entry;
294 
295 	/* The message itself */
296 	unsigned char msg[];
297 };
298 
299 
300 extern struct vmbus_connection vmbus_connection;
301 
302 int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version);
303 
304 static inline void vmbus_send_interrupt(u32 relid)
305 {
306 	sync_set_bit(relid, vmbus_connection.send_int_page);
307 }
308 
309 enum vmbus_message_handler_type {
310 	/* The related handler can sleep. */
311 	VMHT_BLOCKING = 0,
312 
313 	/* The related handler must NOT sleep. */
314 	VMHT_NON_BLOCKING = 1,
315 };
316 
317 struct vmbus_channel_message_table_entry {
318 	enum vmbus_channel_message_type message_type;
319 	enum vmbus_message_handler_type handler_type;
320 	void (*message_handler)(struct vmbus_channel_message_header *msg);
321 	u32 min_payload_len;
322 };
323 
324 extern const struct vmbus_channel_message_table_entry
325 	channel_message_table[CHANNELMSG_COUNT];
326 
327 
328 /* General vmbus interface */
329 
330 struct hv_device *vmbus_device_create(const guid_t *type,
331 				      const guid_t *instance,
332 				      struct vmbus_channel *channel);
333 
334 int vmbus_device_register(struct hv_device *child_device_obj);
335 void vmbus_device_unregister(struct hv_device *device_obj);
336 int vmbus_add_channel_kobj(struct hv_device *device_obj,
337 			   struct vmbus_channel *channel);
338 
339 void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
340 
341 struct vmbus_channel *relid2channel(u32 relid);
342 
343 void vmbus_free_channels(void);
344 
345 /* Connection interface */
346 
347 int vmbus_connect(void);
348 void vmbus_disconnect(void);
349 
350 int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
351 
352 void vmbus_on_event(unsigned long data);
353 void vmbus_on_msg_dpc(unsigned long data);
354 
355 int hv_kvp_init(struct hv_util_service *srv);
356 void hv_kvp_deinit(void);
357 int hv_kvp_pre_suspend(void);
358 int hv_kvp_pre_resume(void);
359 void hv_kvp_onchannelcallback(void *context);
360 
361 int hv_vss_init(struct hv_util_service *srv);
362 void hv_vss_deinit(void);
363 int hv_vss_pre_suspend(void);
364 int hv_vss_pre_resume(void);
365 void hv_vss_onchannelcallback(void *context);
366 
367 int hv_fcopy_init(struct hv_util_service *srv);
368 void hv_fcopy_deinit(void);
369 int hv_fcopy_pre_suspend(void);
370 int hv_fcopy_pre_resume(void);
371 void hv_fcopy_onchannelcallback(void *context);
372 void vmbus_initiate_unload(bool crash);
373 
374 static inline void hv_poll_channel(struct vmbus_channel *channel,
375 				   void (*cb)(void *))
376 {
377 	if (!channel)
378 		return;
379 
380 	if (in_interrupt() && (channel->target_cpu == smp_processor_id())) {
381 		cb(channel);
382 		return;
383 	}
384 	smp_call_function_single(channel->target_cpu, cb, channel, true);
385 }
386 
387 enum hvutil_device_state {
388 	HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
389 	HVUTIL_READY,            /* userspace is registered */
390 	HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
391 	HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
392 	HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
393 	HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
394 };
395 
396 enum delay {
397 	INTERRUPT_DELAY = 0,
398 	MESSAGE_DELAY   = 1,
399 };
400 
401 #ifdef CONFIG_HYPERV_TESTING
402 
403 int hv_debug_add_dev_dir(struct hv_device *dev);
404 void hv_debug_rm_dev_dir(struct hv_device *dev);
405 void hv_debug_rm_all_dir(void);
406 int hv_debug_init(void);
407 void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
408 
409 #else /* CONFIG_HYPERV_TESTING */
410 
411 static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {};
412 static inline void hv_debug_rm_all_dir(void) {};
413 static inline void hv_debug_delay_test(struct vmbus_channel *channel,
414 				       enum delay delay_type) {};
415 static inline int hv_debug_init(void)
416 {
417 	return -1;
418 }
419 
420 static inline int hv_debug_add_dev_dir(struct hv_device *dev)
421 {
422 	return -1;
423 }
424 
425 #endif /* CONFIG_HYPERV_TESTING */
426 
427 #endif /* _HYPERV_VMBUS_H */
428