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 */
37union hv_monitor_trigger_group {
38	u64 as_uint64;
39	struct {
40		u32 pending;
41		u32 armed;
42	};
43};
44
45struct hv_monitor_parameter {
46	union hv_connection_id connectionid;
47	u16 flagnumber;
48	u16 rsvdz;
49};
50
51union 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/* ------------------------------------------------------ */
79struct 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. */
99struct 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
108enum {
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 */
122struct 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
145struct 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
160extern struct hv_context hv_context;
161
162/* Hv Interface */
163
164extern int hv_init(void);
165
166extern 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
170extern int hv_synic_alloc(void);
171
172extern void hv_synic_free(void);
173
174extern void hv_synic_enable_regs(unsigned int cpu);
175extern int hv_synic_init(unsigned int cpu);
176
177extern void hv_synic_disable_regs(unsigned int cpu);
178extern int hv_synic_cleanup(unsigned int cpu);
179
180/* Interface */
181
182void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
183
184int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
185		       struct page *pages, u32 pagecnt, u32 max_pkt_size);
186
187void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
188
189int hv_ringbuffer_write(struct vmbus_channel *channel,
190			const struct kvec *kv_list, u32 kv_count,
191			u64 requestid, u64 *trans_id);
192
193int 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
210enum 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
225struct 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
305struct vmbus_msginfo {
306	/* Bookkeeping stuff */
307	struct list_head msglist_entry;
308
309	/* The message itself */
310	unsigned char msg[];
311};
312
313
314extern struct vmbus_connection vmbus_connection;
315
316int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version);
317
318static inline void vmbus_send_interrupt(u32 relid)
319{
320	sync_set_bit(relid, vmbus_connection.send_int_page);
321}
322
323enum 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
331struct 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
338extern const struct vmbus_channel_message_table_entry
339	channel_message_table[CHANNELMSG_COUNT];
340
341
342/* General vmbus interface */
343
344struct hv_device *vmbus_device_create(const guid_t *type,
345				      const guid_t *instance,
346				      struct vmbus_channel *channel);
347
348int vmbus_device_register(struct hv_device *child_device_obj);
349void vmbus_device_unregister(struct hv_device *device_obj);
350int vmbus_add_channel_kobj(struct hv_device *device_obj,
351			   struct vmbus_channel *channel);
352
353void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
354
355void vmbus_channel_map_relid(struct vmbus_channel *channel);
356void vmbus_channel_unmap_relid(struct vmbus_channel *channel);
357
358struct vmbus_channel *relid2channel(u32 relid);
359
360void vmbus_free_channels(void);
361
362/* Connection interface */
363
364int vmbus_connect(void);
365void vmbus_disconnect(void);
366
367int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
368
369void vmbus_on_event(unsigned long data);
370void vmbus_on_msg_dpc(unsigned long data);
371
372int hv_kvp_init(struct hv_util_service *srv);
373void hv_kvp_deinit(void);
374int hv_kvp_pre_suspend(void);
375int hv_kvp_pre_resume(void);
376void hv_kvp_onchannelcallback(void *context);
377
378int hv_vss_init(struct hv_util_service *srv);
379void hv_vss_deinit(void);
380int hv_vss_pre_suspend(void);
381int hv_vss_pre_resume(void);
382void hv_vss_onchannelcallback(void *context);
383
384int hv_fcopy_init(struct hv_util_service *srv);
385void hv_fcopy_deinit(void);
386int hv_fcopy_pre_suspend(void);
387int hv_fcopy_pre_resume(void);
388void hv_fcopy_onchannelcallback(void *context);
389void vmbus_initiate_unload(bool crash);
390
391static inline void hv_poll_channel(struct vmbus_channel *channel,
392				   void (*cb)(void *))
393{
394	if (!channel)
395		return;
396	cb(channel);
397}
398
399enum 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
408enum delay {
409	INTERRUPT_DELAY = 0,
410	MESSAGE_DELAY   = 1,
411};
412
413extern const struct vmbus_device vmbus_devs[];
414
415static inline bool hv_is_perf_channel(struct vmbus_channel *channel)
416{
417	return vmbus_devs[channel->device_id].perf_device;
418}
419
420static inline bool hv_is_allocated_cpu(unsigned int cpu)
421{
422	struct vmbus_channel *channel, *sc;
423
424	lockdep_assert_held(&vmbus_connection.channel_mutex);
425	/*
426	 * List additions/deletions as well as updates of the target CPUs are
427	 * protected by channel_mutex.
428	 */
429	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
430		if (!hv_is_perf_channel(channel))
431			continue;
432		if (channel->target_cpu == cpu)
433			return true;
434		list_for_each_entry(sc, &channel->sc_list, sc_list) {
435			if (sc->target_cpu == cpu)
436				return true;
437		}
438	}
439	return false;
440}
441
442static inline void hv_set_allocated_cpu(unsigned int cpu)
443{
444	cpumask_set_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
445}
446
447static inline void hv_clear_allocated_cpu(unsigned int cpu)
448{
449	if (hv_is_allocated_cpu(cpu))
450		return;
451	cpumask_clear_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
452}
453
454static inline void hv_update_allocated_cpus(unsigned int old_cpu,
455					  unsigned int new_cpu)
456{
457	hv_set_allocated_cpu(new_cpu);
458	hv_clear_allocated_cpu(old_cpu);
459}
460
461#ifdef CONFIG_HYPERV_TESTING
462
463int hv_debug_add_dev_dir(struct hv_device *dev);
464void hv_debug_rm_dev_dir(struct hv_device *dev);
465void hv_debug_rm_all_dir(void);
466int hv_debug_init(void);
467void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
468
469#else /* CONFIG_HYPERV_TESTING */
470
471static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {};
472static inline void hv_debug_rm_all_dir(void) {};
473static inline void hv_debug_delay_test(struct vmbus_channel *channel,
474				       enum delay delay_type) {};
475static inline int hv_debug_init(void)
476{
477	return -1;
478}
479
480static inline int hv_debug_add_dev_dir(struct hv_device *dev)
481{
482	return -1;
483}
484
485#endif /* CONFIG_HYPERV_TESTING */
486
487#endif /* _HYPERV_VMBUS_H */
488