xref: /openbmc/linux/drivers/hv/hyperv_vmbus.h (revision 6355592e)
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 int hv_synic_init(unsigned int cpu);
173 
174 extern int hv_synic_cleanup(unsigned int cpu);
175 
176 /* Interface */
177 
178 void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
179 
180 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
181 		       struct page *pages, u32 pagecnt);
182 
183 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
184 
185 int hv_ringbuffer_write(struct vmbus_channel *channel,
186 			const struct kvec *kv_list, u32 kv_count);
187 
188 int hv_ringbuffer_read(struct vmbus_channel *channel,
189 		       void *buffer, u32 buflen, u32 *buffer_actual_len,
190 		       u64 *requestid, bool raw);
191 
192 /*
193  * The Maximum number of channels (16348) is determined by the size of the
194  * interrupt page, which is HV_HYP_PAGE_SIZE. 1/2 of HV_HYP_PAGE_SIZE is to
195  * send endpoint interrupts, and the other is to receive endpoint interrupts.
196  */
197 #define MAX_NUM_CHANNELS	((HV_HYP_PAGE_SIZE >> 1) << 3)
198 
199 /* The value here must be in multiple of 32 */
200 /* TODO: Need to make this configurable */
201 #define MAX_NUM_CHANNELS_SUPPORTED	256
202 
203 
204 enum vmbus_connect_state {
205 	DISCONNECTED,
206 	CONNECTING,
207 	CONNECTED,
208 	DISCONNECTING
209 };
210 
211 #define MAX_SIZE_CHANNEL_MESSAGE	HV_MESSAGE_PAYLOAD_BYTE_COUNT
212 
213 struct vmbus_connection {
214 	/*
215 	 * CPU on which the initial host contact was made.
216 	 */
217 	int connect_cpu;
218 
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 	struct list_head chn_msg_list;
245 	spinlock_t channelmsg_lock;
246 
247 	/* List of channels */
248 	struct list_head chn_list;
249 	struct mutex channel_mutex;
250 
251 	/*
252 	 * An offer message is handled first on the work_queue, and then
253 	 * is further handled on handle_primary_chan_wq or
254 	 * handle_sub_chan_wq.
255 	 */
256 	struct workqueue_struct *work_queue;
257 	struct workqueue_struct *handle_primary_chan_wq;
258 	struct workqueue_struct *handle_sub_chan_wq;
259 };
260 
261 
262 struct vmbus_msginfo {
263 	/* Bookkeeping stuff */
264 	struct list_head msglist_entry;
265 
266 	/* The message itself */
267 	unsigned char msg[0];
268 };
269 
270 
271 extern struct vmbus_connection vmbus_connection;
272 
273 static inline void vmbus_send_interrupt(u32 relid)
274 {
275 	sync_set_bit(relid, vmbus_connection.send_int_page);
276 }
277 
278 enum vmbus_message_handler_type {
279 	/* The related handler can sleep. */
280 	VMHT_BLOCKING = 0,
281 
282 	/* The related handler must NOT sleep. */
283 	VMHT_NON_BLOCKING = 1,
284 };
285 
286 struct vmbus_channel_message_table_entry {
287 	enum vmbus_channel_message_type message_type;
288 	enum vmbus_message_handler_type handler_type;
289 	void (*message_handler)(struct vmbus_channel_message_header *msg);
290 };
291 
292 extern const struct vmbus_channel_message_table_entry
293 	channel_message_table[CHANNELMSG_COUNT];
294 
295 
296 /* General vmbus interface */
297 
298 struct hv_device *vmbus_device_create(const guid_t *type,
299 				      const guid_t *instance,
300 				      struct vmbus_channel *channel);
301 
302 int vmbus_device_register(struct hv_device *child_device_obj);
303 void vmbus_device_unregister(struct hv_device *device_obj);
304 int vmbus_add_channel_kobj(struct hv_device *device_obj,
305 			   struct vmbus_channel *channel);
306 
307 void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
308 
309 struct vmbus_channel *relid2channel(u32 relid);
310 
311 void vmbus_free_channels(void);
312 
313 /* Connection interface */
314 
315 int vmbus_connect(void);
316 void vmbus_disconnect(void);
317 
318 int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
319 
320 void vmbus_on_event(unsigned long data);
321 void vmbus_on_msg_dpc(unsigned long data);
322 
323 int hv_kvp_init(struct hv_util_service *srv);
324 void hv_kvp_deinit(void);
325 void hv_kvp_onchannelcallback(void *context);
326 
327 int hv_vss_init(struct hv_util_service *srv);
328 void hv_vss_deinit(void);
329 void hv_vss_onchannelcallback(void *context);
330 
331 int hv_fcopy_init(struct hv_util_service *srv);
332 void hv_fcopy_deinit(void);
333 void hv_fcopy_onchannelcallback(void *context);
334 void vmbus_initiate_unload(bool crash);
335 
336 static inline void hv_poll_channel(struct vmbus_channel *channel,
337 				   void (*cb)(void *))
338 {
339 	if (!channel)
340 		return;
341 
342 	if (in_interrupt() && (channel->target_cpu == smp_processor_id())) {
343 		cb(channel);
344 		return;
345 	}
346 	smp_call_function_single(channel->target_cpu, cb, channel, true);
347 }
348 
349 enum hvutil_device_state {
350 	HVUTIL_DEVICE_INIT = 0,  /* driver is loaded, waiting for userspace */
351 	HVUTIL_READY,            /* userspace is registered */
352 	HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
353 	HVUTIL_USERSPACE_REQ,    /* request to userspace was sent */
354 	HVUTIL_USERSPACE_RECV,   /* reply from userspace was received */
355 	HVUTIL_DEVICE_DYING,     /* driver unload is in progress */
356 };
357 
358 #endif /* _HYPERV_VMBUS_H */
359