xref: /openbmc/qemu/include/hw/hyperv/dynmem-proto.h (revision 34cc54fb)
1 #ifndef HW_HYPERV_DYNMEM_PROTO_H
2 #define HW_HYPERV_DYNMEM_PROTO_H
3 
4 /*
5  * Hyper-V Dynamic Memory Protocol definitions
6  *
7  * Copyright (C) 2020-2023 Oracle and/or its affiliates.
8  *
9  * Based on drivers/hv/hv_balloon.c from Linux kernel:
10  * Copyright (c) 2012, Microsoft Corporation.
11  *
12  * Author: K. Y. Srinivasan <kys@microsoft.com>
13  *
14  * This work is licensed under the terms of the GNU GPL, version 2.
15  * See the COPYING file in the top-level directory.
16  */
17 
18 /*
19  * Protocol versions. The low word is the minor version, the high word the major
20  * version.
21  *
22  * History:
23  * Initial version 1.0
24  * Changed to 0.1 on 2009/03/25
25  * Changes to 0.2 on 2009/05/14
26  * Changes to 0.3 on 2009/12/03
27  * Changed to 1.0 on 2011/04/05
28  * Changed to 2.0 on 2019/12/10
29  */
30 
31 #define DYNMEM_MAKE_VERSION(Major, Minor) ((uint32_t)(((Major) << 16) | (Minor)))
32 #define DYNMEM_MAJOR_VERSION(Version) ((uint32_t)(Version) >> 16)
33 #define DYNMEM_MINOR_VERSION(Version) ((uint32_t)(Version) & 0xff)
34 
35 enum {
36     DYNMEM_PROTOCOL_VERSION_1 = DYNMEM_MAKE_VERSION(0, 3),
37     DYNMEM_PROTOCOL_VERSION_2 = DYNMEM_MAKE_VERSION(1, 0),
38     DYNMEM_PROTOCOL_VERSION_3 = DYNMEM_MAKE_VERSION(2, 0),
39 
40     DYNMEM_PROTOCOL_VERSION_WIN7 = DYNMEM_PROTOCOL_VERSION_1,
41     DYNMEM_PROTOCOL_VERSION_WIN8 = DYNMEM_PROTOCOL_VERSION_2,
42     DYNMEM_PROTOCOL_VERSION_WIN10 = DYNMEM_PROTOCOL_VERSION_3,
43 
44     DYNMEM_PROTOCOL_VERSION_CURRENT = DYNMEM_PROTOCOL_VERSION_WIN10
45 };
46 
47 
48 
49 /*
50  * Message Types
51  */
52 
53 enum dm_message_type {
54     /*
55      * Version 0.3
56      */
57     DM_ERROR = 0,
58     DM_VERSION_REQUEST = 1,
59     DM_VERSION_RESPONSE = 2,
60     DM_CAPABILITIES_REPORT = 3,
61     DM_CAPABILITIES_RESPONSE = 4,
62     DM_STATUS_REPORT = 5,
63     DM_BALLOON_REQUEST = 6,
64     DM_BALLOON_RESPONSE = 7,
65     DM_UNBALLOON_REQUEST = 8,
66     DM_UNBALLOON_RESPONSE = 9,
67     DM_MEM_HOT_ADD_REQUEST = 10,
68     DM_MEM_HOT_ADD_RESPONSE = 11,
69     DM_VERSION_03_MAX = 11,
70     /*
71      * Version 1.0.
72      */
73     DM_INFO_MESSAGE = 12,
74     DM_VERSION_1_MAX = 12,
75 
76     /*
77      * Version 2.0
78      */
79     DM_MEM_HOT_REMOVE_REQUEST = 13,
80     DM_MEM_HOT_REMOVE_RESPONSE = 14
81 };
82 
83 
84 /*
85  * Structures defining the dynamic memory management
86  * protocol.
87  */
88 
89 union dm_version {
90     struct {
91         uint16_t minor_version;
92         uint16_t major_version;
93     };
94     uint32_t version;
95 } QEMU_PACKED;
96 
97 
98 union dm_caps {
99     struct {
100         uint64_t balloon:1;
101         uint64_t hot_add:1;
102         /*
103          * To support guests that may have alignment
104          * limitations on hot-add, the guest can specify
105          * its alignment requirements; a value of n
106          * represents an alignment of 2^n in mega bytes.
107          */
108         uint64_t hot_add_alignment:4;
109         uint64_t hot_remove:1;
110         uint64_t reservedz:57;
111     } cap_bits;
112     uint64_t caps;
113 } QEMU_PACKED;
114 
115 union dm_mem_page_range {
116     struct  {
117         /*
118          * The PFN number of the first page in the range.
119          * 40 bits is the architectural limit of a PFN
120          * number for AMD64.
121          */
122         uint64_t start_page:40;
123         /*
124          * The number of pages in the range.
125          */
126         uint64_t page_cnt:24;
127     } finfo;
128     uint64_t  page_range;
129 } QEMU_PACKED;
130 
131 
132 
133 /*
134  * The header for all dynamic memory messages:
135  *
136  * type: Type of the message.
137  * size: Size of the message in bytes; including the header.
138  * trans_id: The guest is responsible for manufacturing this ID.
139  */
140 
141 struct dm_header {
142     uint16_t type;
143     uint16_t size;
144     uint32_t trans_id;
145 } QEMU_PACKED;
146 
147 /*
148  * A generic message format for dynamic memory.
149  * Specific message formats are defined later in the file.
150  */
151 
152 struct dm_message {
153     struct dm_header hdr;
154     uint8_t data[]; /* enclosed message */
155 } QEMU_PACKED;
156 
157 
158 /*
159  * Specific message types supporting the dynamic memory protocol.
160  */
161 
162 /*
163  * Version negotiation message. Sent from the guest to the host.
164  * The guest is free to try different versions until the host
165  * accepts the version.
166  *
167  * dm_version: The protocol version requested.
168  * is_last_attempt: If TRUE, this is the last version guest will request.
169  * reservedz: Reserved field, set to zero.
170  */
171 
172 struct dm_version_request {
173     struct dm_header hdr;
174     union dm_version version;
175     uint32_t is_last_attempt:1;
176     uint32_t reservedz:31;
177 } QEMU_PACKED;
178 
179 /*
180  * Version response message; Host to Guest and indicates
181  * if the host has accepted the version sent by the guest.
182  *
183  * is_accepted: If TRUE, host has accepted the version and the guest
184  * should proceed to the next stage of the protocol. FALSE indicates that
185  * guest should re-try with a different version.
186  *
187  * reservedz: Reserved field, set to zero.
188  */
189 
190 struct dm_version_response {
191     struct dm_header hdr;
192     uint64_t is_accepted:1;
193     uint64_t reservedz:63;
194 } QEMU_PACKED;
195 
196 /*
197  * Message reporting capabilities. This is sent from the guest to the
198  * host.
199  */
200 
201 struct dm_capabilities {
202     struct dm_header hdr;
203     union dm_caps caps;
204     uint64_t min_page_cnt;
205     uint64_t max_page_number;
206 } QEMU_PACKED;
207 
208 /*
209  * Response to the capabilities message. This is sent from the host to the
210  * guest. This message notifies if the host has accepted the guest's
211  * capabilities. If the host has not accepted, the guest must shutdown
212  * the service.
213  *
214  * is_accepted: Indicates if the host has accepted guest's capabilities.
215  * reservedz: Must be 0.
216  */
217 
218 struct dm_capabilities_resp_msg {
219     struct dm_header hdr;
220     uint64_t is_accepted:1;
221     uint64_t hot_remove:1;
222     uint64_t suppress_pressure_reports:1;
223     uint64_t reservedz:61;
224 } QEMU_PACKED;
225 
226 /*
227  * This message is used to report memory pressure from the guest.
228  * This message is not part of any transaction and there is no
229  * response to this message.
230  *
231  * num_avail: Available memory in pages.
232  * num_committed: Committed memory in pages.
233  * page_file_size: The accumulated size of all page files
234  *                 in the system in pages.
235  * zero_free: The number of zero and free pages.
236  * page_file_writes: The writes to the page file in pages.
237  * io_diff: An indicator of file cache efficiency or page file activity,
238  *          calculated as File Cache Page Fault Count - Page Read Count.
239  *          This value is in pages.
240  *
241  * Some of these metrics are Windows specific and fortunately
242  * the algorithm on the host side that computes the guest memory
243  * pressure only uses num_committed value.
244  */
245 
246 struct dm_status {
247     struct dm_header hdr;
248     uint64_t num_avail;
249     uint64_t num_committed;
250     uint64_t page_file_size;
251     uint64_t zero_free;
252     uint32_t page_file_writes;
253     uint32_t io_diff;
254 } QEMU_PACKED;
255 
256 
257 /*
258  * Message to ask the guest to allocate memory - balloon up message.
259  * This message is sent from the host to the guest. The guest may not be
260  * able to allocate as much memory as requested.
261  *
262  * num_pages: number of pages to allocate.
263  */
264 
265 struct dm_balloon {
266     struct dm_header hdr;
267     uint32_t num_pages;
268     uint32_t reservedz;
269 } QEMU_PACKED;
270 
271 
272 /*
273  * Balloon response message; this message is sent from the guest
274  * to the host in response to the balloon message.
275  *
276  * reservedz: Reserved; must be set to zero.
277  * more_pages: If FALSE, this is the last message of the transaction.
278  * if TRUE there will be at least one more message from the guest.
279  *
280  * range_count: The number of ranges in the range array.
281  *
282  * range_array: An array of page ranges returned to the host.
283  *
284  */
285 
286 struct dm_balloon_response {
287     struct dm_header hdr;
288     uint32_t reservedz;
289     uint32_t more_pages:1;
290     uint32_t range_count:31;
291     union dm_mem_page_range range_array[];
292 } QEMU_PACKED;
293 
294 /*
295  * Un-balloon message; this message is sent from the host
296  * to the guest to give guest more memory.
297  *
298  * more_pages: If FALSE, this is the last message of the transaction.
299  * if TRUE there will be at least one more message from the guest.
300  *
301  * reservedz: Reserved; must be set to zero.
302  *
303  * range_count: The number of ranges in the range array.
304  *
305  * range_array: An array of page ranges returned to the host.
306  *
307  */
308 
309 struct dm_unballoon_request {
310     struct dm_header hdr;
311     uint32_t more_pages:1;
312     uint32_t reservedz:31;
313     uint32_t range_count;
314     union dm_mem_page_range range_array[];
315 } QEMU_PACKED;
316 
317 /*
318  * Un-balloon response message; this message is sent from the guest
319  * to the host in response to an unballoon request.
320  *
321  */
322 
323 struct dm_unballoon_response {
324     struct dm_header hdr;
325 } QEMU_PACKED;
326 
327 
328 /*
329  * Hot add request message. Message sent from the host to the guest.
330  *
331  * range: Memory range to hot add.
332  * region: Explicit hot add memory region for guest to use. Optional.
333  *
334  */
335 
336 struct dm_hot_add {
337     struct dm_header hdr;
338     union dm_mem_page_range range;
339 } QEMU_PACKED;
340 
341 struct dm_hot_add_with_region {
342     struct dm_header hdr;
343     union dm_mem_page_range range;
344     union dm_mem_page_range region;
345 } QEMU_PACKED;
346 
347 /*
348  * Hot add response message.
349  * This message is sent by the guest to report the status of a hot add request.
350  * If page_count is less than the requested page count, then the host should
351  * assume all further hot add requests will fail, since this indicates that
352  * the guest has hit an upper physical memory barrier.
353  *
354  * Hot adds may also fail due to low resources; in this case, the guest must
355  * not complete this message until the hot add can succeed, and the host must
356  * not send a new hot add request until the response is sent.
357  * If VSC fails to hot add memory DYNMEM_NUMBER_OF_UNSUCCESSFUL_HOTADD_ATTEMPTS
358  * times it fails the request.
359  *
360  *
361  * page_count: number of pages that were successfully hot added.
362  *
363  * result: result of the operation 1: success, 0: failure.
364  *
365  */
366 
367 struct dm_hot_add_response {
368     struct dm_header hdr;
369     uint32_t page_count;
370     uint32_t result;
371 } QEMU_PACKED;
372 
373 struct dm_hot_remove {
374     struct dm_header hdr;
375     uint32_t virtual_node;
376     uint32_t page_count;
377     uint32_t qos_flags;
378     uint32_t reservedZ;
379 } QEMU_PACKED;
380 
381 struct dm_hot_remove_response {
382     struct dm_header hdr;
383     uint32_t result;
384     uint32_t range_count;
385     uint64_t more_pages:1;
386     uint64_t reservedz:63;
387     union dm_mem_page_range range_array[];
388 } QEMU_PACKED;
389 
390 #define DM_REMOVE_QOS_LARGE (1 << 0)
391 #define DM_REMOVE_QOS_LOCAL (1 << 1)
392 #define DM_REMOVE_QOS_MASK (0x3)
393 
394 /*
395  * Types of information sent from host to the guest.
396  */
397 
398 enum dm_info_type {
399     INFO_TYPE_MAX_PAGE_CNT = 0,
400     MAX_INFO_TYPE
401 };
402 
403 
404 /*
405  * Header for the information message.
406  */
407 
408 struct dm_info_header {
409     enum dm_info_type type;
410     uint32_t data_size;
411     uint8_t  data[];
412 } QEMU_PACKED;
413 
414 /*
415  * This message is sent from the host to the guest to pass
416  * some relevant information (win8 addition).
417  *
418  * reserved: no used.
419  * info_size: size of the information blob.
420  * info: information blob.
421  */
422 
423 struct dm_info_msg {
424     struct dm_header hdr;
425     uint32_t reserved;
426     uint32_t info_size;
427     uint8_t  info[];
428 };
429 
430 #endif
431