1 /* Copyright (C) 2010 - 2013 UNISYS CORPORATION
2  * All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or (at
7  * your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
12  * NON INFRINGEMENT.  See the GNU General Public License for more
13  * details.
14  */
15 
16 #ifndef __CONTROLVMCHANNEL_H__
17 #define __CONTROLVMCHANNEL_H__
18 
19 #include <linux/uuid.h>
20 #include "channel.h"
21 #include "controlframework.h"
22 
23 typedef u64 GUEST_PHYSICAL_ADDRESS;
24 
25 enum { INVALID_GUEST_FIRMWARE, SAMPLE_GUEST_FIRMWARE,
26 	    TIANO32_GUEST_FIRMWARE, TIANO64_GUEST_FIRMWARE
27 };
28 
29 /* {2B3C2D10-7EF5-4ad8-B966-3448B7386B3D} */
30 #define SPAR_CONTROLVM_CHANNEL_PROTOCOL_UUID	\
31 		UUID_LE(0x2b3c2d10, 0x7ef5, 0x4ad8, \
32 				0xb9, 0x66, 0x34, 0x48, 0xb7, 0x38, 0x6b, 0x3d)
33 
34 static const uuid_le spar_controlvm_channel_protocol_uuid =
35 	SPAR_CONTROLVM_CHANNEL_PROTOCOL_UUID;
36 
37 #define ULTRA_CONTROLVM_CHANNEL_PROTOCOL_SIGNATURE \
38 	ULTRA_CHANNEL_PROTOCOL_SIGNATURE
39 #define CONTROLVM_MESSAGE_MAX     64
40 
41 /* Must increment this whenever you insert or delete fields within
42 * this channel struct.  Also increment whenever you change the meaning
43 * of fields within this channel struct so as to break pre-existing
44 * software.  Note that you can usually add fields to the END of the
45 * channel struct withOUT needing to increment this. */
46 #define ULTRA_CONTROLVM_CHANNEL_PROTOCOL_VERSIONID  1
47 
48 #define SPAR_CONTROLVM_CHANNEL_OK_CLIENT(ch)           \
49 	spar_check_channel_client(ch, \
50 		spar_controlvm_channel_protocol_uuid, \
51 		"controlvm", \
52 		sizeof(struct spar_controlvm_channel_protocol), \
53 		ULTRA_CONTROLVM_CHANNEL_PROTOCOL_VERSIONID, \
54 		ULTRA_CONTROLVM_CHANNEL_PROTOCOL_SIGNATURE)
55 
56 #define MY_DEVICE_INDEX 0
57 #define MAX_MACDATA_LEN 8 /* number of bytes for MAC address in config packet */
58 #define MAX_SERIAL_NUM	32
59 
60 #define DISK_ZERO_PUN_NUMBER	1  /* Target ID on the SCSI bus for LUN 0 */
61 #define DISK_ZERO_LUN_NUMBER	3  /* Logical Unit Number */
62 
63 /* Defines for various channel queues... */
64 #define CONTROLVM_QUEUE_REQUEST		0
65 #define CONTROLVM_QUEUE_RESPONSE	1
66 #define	CONTROLVM_QUEUE_EVENT		2
67 #define CONTROLVM_QUEUE_ACK		3
68 
69 /* Max number of messages stored during IOVM creation to be reused
70  * after crash */
71 #define CONTROLVM_CRASHMSG_MAX		2
72 
73 /** Ids for commands that may appear in either queue of a ControlVm channel.
74  *
75  *  Commands that are initiated by the command partition (CP), by an IO or
76  *  console service partition (SP), or by a guest partition (GP)are:
77  *  - issued on the RequestQueue queue (q #0) in the ControlVm channel
78  *  - responded to on the ResponseQueue queue (q #1) in the ControlVm channel
79  *
80  *  Events that are initiated by an IO or console service partition (SP) or
81  *  by a guest partition (GP) are:
82  *  - issued on the EventQueue queue (q #2) in the ControlVm channel
83  *  - responded to on the EventAckQueue queue (q #3) in the ControlVm channel
84  */
85 enum controlvm_id {
86 	CONTROLVM_INVALID = 0,
87 	/* SWITCH commands required Parameter: SwitchNumber  */
88 	/* BUS commands required Parameter: BusNumber  */
89 	CONTROLVM_BUS_CREATE = 0x101,	/* CP --> SP, GP */
90 	CONTROLVM_BUS_DESTROY = 0x102,	/* CP --> SP, GP */
91 	CONTROLVM_BUS_CONFIGURE = 0x104,	/* CP --> SP */
92 	CONTROLVM_BUS_CHANGESTATE = 0x105,	/* CP --> SP, GP */
93 	CONTROLVM_BUS_CHANGESTATE_EVENT = 0x106, /* SP, GP --> CP */
94 /* DEVICE commands required Parameter: BusNumber, DeviceNumber  */
95 
96 	CONTROLVM_DEVICE_CREATE = 0x201,	/* CP --> SP, GP */
97 	CONTROLVM_DEVICE_DESTROY = 0x202,	/* CP --> SP, GP */
98 	CONTROLVM_DEVICE_CONFIGURE = 0x203,	/* CP --> SP */
99 	CONTROLVM_DEVICE_CHANGESTATE = 0x204,	/* CP --> SP, GP */
100 	CONTROLVM_DEVICE_CHANGESTATE_EVENT = 0x205, /* SP, GP --> CP */
101 	CONTROLVM_DEVICE_RECONFIGURE = 0x206,	/* CP --> Boot */
102 /* DISK commands required Parameter: BusNumber, DeviceNumber  */
103 	CONTROLVM_DISK_CREATE = 0x221,	/* CP --> SP */
104 	CONTROLVM_DISK_DESTROY = 0x222,	/* CP --> SP */
105 	CONTROLVM_DISK_CONFIGURE = 0x223,	/* CP --> SP */
106 	CONTROLVM_DISK_CHANGESTATE = 0x224,	/* CP --> SP */
107 /* CHIPSET commands */
108 	CONTROLVM_CHIPSET_INIT = 0x301,	/* CP --> SP, GP */
109 	CONTROLVM_CHIPSET_STOP = 0x302,	/* CP --> SP, GP */
110 	CONTROLVM_CHIPSET_SHUTDOWN = 0x303,	/* CP --> SP */
111 	CONTROLVM_CHIPSET_READY = 0x304,	/* CP --> SP */
112 	CONTROLVM_CHIPSET_SELFTEST = 0x305,	/* CP --> SP */
113 
114 };
115 
116 struct irq_info {
117 	 /**< specifies interrupt info. It is used to send interrupts
118 	  *   for this channel. The peer at the end of this channel
119 	  *   who has registered an interrupt (using recv fields
120 	  *   above) will receive the interrupt. Passed as a parameter
121 	  *   to Issue_VMCALL_IO_QUEUE_TRANSITION, which generates the
122 	  *   interrupt.  Currently this is used by IOPart-SP to wake
123 	  *   up GP when Data Channel transitions from empty to
124 	  *   non-empty.*/
125 	u64 send_irq_handle;
126 
127 	 /**< specifies interrupt handle. It is used to retrieve the
128 	  *   corresponding interrupt pin from Monitor; and the
129 	  *   interrupt pin is used to connect to the corresponding
130 	  *   interrupt.  Used by IOPart-GP only. */
131 	u64 recv_irq_handle;
132 
133 	 /**< specifies interrupt vector. It, interrupt pin, and shared are
134 	  *   used to connect to the corresponding interrupt.  Used by
135 	  *   IOPart-GP only. */
136 	u32 recv_irq_vector;
137 
138     /**< specifies if the recvInterrupt is shared.  It, interrupt pin
139      *   and vector are used to connect to 0 = not shared; 1 = shared.
140      *   the corresponding interrupt.  Used by IOPart-GP only. */
141 	u8 recv_irq_shared;
142 	u8 reserved[3];	/* Natural alignment purposes */
143 };
144 
145 struct pci_id {
146 	u16 domain;
147 	u8 bus;
148 	u8 slot;
149 	u8 func;
150 	u8 reserved[3];	/* Natural alignment purposes */
151 };
152 
153 struct efi_spar_indication  {
154 	u64 boot_to_fw_ui:1;	/* Bit 0: Stop in uefi ui */
155 	u64 clear_nvram:1;	/* Bit 1: Clear NVRAM */
156 	u64 clear_cmos:1;	/* Bit 2: Clear CMOS */
157 	u64 boot_to_tool:1;	/* Bit 3: Run install tool */
158 	/* remaining bits are available */
159 };
160 
161 enum ultra_chipset_feature {
162 	ULTRA_CHIPSET_FEATURE_REPLY = 0x00000001,
163 	ULTRA_CHIPSET_FEATURE_PARA_HOTPLUG = 0x00000002,
164 	ULTRA_CHIPSET_FEATURE_PCIVBUS = 0x00000004
165 };
166 
167 /** This is the common structure that is at the beginning of every
168  *  ControlVm message (both commands and responses) in any ControlVm
169  *  queue.  Commands are easily distinguished from responses by
170  *  looking at the flags.response field.
171  */
172 struct controlvm_message_header  {
173 	u32 id;		/* See CONTROLVM_ID. */
174 	/* For requests, indicates the message type. */
175 	/* For responses, indicates the type of message we are responding to. */
176 
177 	u32 message_size;	/* Includes size of this struct + size
178 				 * of message */
179 	u32 segment_index;	/* Index of segment containing Vm
180 				 * message/information */
181 	u32 completion_status;	/* Error status code or result of
182 				 * message completion */
183 	struct  {
184 		u32 failed:1;		   /**< =1 in a response to * signify
185 					    * failure */
186 		u32 response_expected:1;   /**< =1 in all messages that expect a
187 					   * response (Control ignores this
188 					   * bit) */
189 		u32 server:1;		   /**< =1 in all bus & device-related
190 					    * messages where the message
191 					    * receiver is to act as the bus or
192 					    * device server */
193 		u32 test_message:1;	   /**< =1 for testing use only
194 					    * (Control and Command ignore this
195 					    * bit) */
196 		u32 partial_completion:1;  /**< =1 if there are forthcoming
197 					   * responses/acks associated
198 					   * with this message */
199 		u32 preserve:1;	       /**< =1 this is to let us know to
200 					* preserve channel contents
201 					* (for running guests)*/
202 		u32 writer_in_diag:1;	/**< =1 the DiagWriter is active in the
203 					 * Diagnostic Partition*/
204 	} flags;
205 	u32 reserved;		/* Natural alignment */
206 	u64 message_handle;	/* Identifies the particular message instance,
207 				 * and is used to match particular */
208 	/* request instances with the corresponding response instance. */
209 	u64 payload_vm_offset;	/* Offset of payload area from start of this
210 				 * instance of ControlVm segment */
211 	u32 payload_max_bytes;	/* Maximum bytes allocated in payload
212 				 * area of ControlVm segment */
213 	u32 payload_bytes;	/* Actual number of bytes of payload
214 				 * area to copy between IO/Command; */
215 	/* if non-zero, there is a payload to copy. */
216 };
217 
218 struct controlvm_packet_device_create  {
219 	u32 bus_no;	/* bus # (0..n-1) from the msg receiver's end */
220 	u32 dev_no;	/* bus-relative (0..n-1) device number */
221 	u64 channel_addr;	/* Guest physical address of the channel, which
222 				 * can be dereferenced by the receiver of this
223 				 * ControlVm command */
224 	u64 channel_bytes;	/* specifies size of the channel in bytes */
225 	uuid_le data_type_uuid;	/* specifies format of data in channel */
226 	uuid_le dev_inst_uuid;	/* instance guid for the device */
227 	struct irq_info intr;	/* specifies interrupt information */
228 };	/* for CONTROLVM_DEVICE_CREATE */
229 
230 struct controlvm_packet_device_configure  {
231 	u32 bus_no;	      /**< bus # (0..n-1) from the msg
232 			       * receiver's perspective */
233 
234 	    /* Control uses header SegmentIndex field to access bus number... */
235 	u32 dev_no;	      /**< bus-relative (0..n-1) device number */
236 } ;	/* for CONTROLVM_DEVICE_CONFIGURE */
237 
238 struct controlvm_message_device_create {
239 	struct controlvm_message_header header;
240 	struct controlvm_packet_device_create packet;
241 };	/* total 128 bytes */
242 
243 struct controlvm_message_device_configure  {
244 	struct controlvm_message_header header;
245 	struct controlvm_packet_device_configure packet;
246 };	/* total 56 bytes */
247 
248 /* This is the format for a message in any ControlVm queue. */
249 struct controlvm_message_packet  {
250 	union  {
251 		struct  {
252 			u32 bus_no;	/* bus # (0..n-1) from the msg
253 					 * receiver's perspective */
254 			u32 dev_count;	/* indicates the max number of
255 					 * devices on this bus */
256 			u64 channel_addr;	/* Guest physical address of
257 						 * the channel, which can be
258 						 * dereferenced by the receiver
259 						 * of this ControlVm command */
260 			u64 channel_bytes;	/* size of the channel */
261 			uuid_le bus_data_type_uuid;	/* indicates format of
262 							 * data in bus channel*/
263 			uuid_le bus_inst_uuid;	/* instance uuid for the bus */
264 		} create_bus;	/* for CONTROLVM_BUS_CREATE */
265 		struct  {
266 			u32 bus_no;	/* bus # (0..n-1) from the msg
267 					 * receiver's perspective */
268 			u32 reserved;	/* Natural alignment purposes */
269 		} destroy_bus;	/* for CONTROLVM_BUS_DESTROY */
270 		struct  {
271 			u32 bus_no;	/* bus # (0..n-1) from the receiver's
272 					 * perspective */
273 			u32 reserved1;	/* for alignment purposes */
274 			u64 guest_handle;	/* This is used to convert
275 						 * guest physical address to
276 						 * physical address */
277 			u64 recv_bus_irq_handle;
278 				/* specifies interrupt info. It is used by SP
279 				 * to register to receive interrupts from the
280 				 * CP. This interrupt is used for bus level
281 				 * notifications.  The corresponding
282 				 * sendBusInterruptHandle is kept in CP. */
283 		} configure_bus;	/* for CONTROLVM_BUS_CONFIGURE */
284 		/* for CONTROLVM_DEVICE_CREATE */
285 		struct controlvm_packet_device_create create_device;
286 		struct  {
287 			u32 bus_no;	/* bus # (0..n-1) from the msg
288 					 * receiver's perspective */
289 			u32 dev_no;	/* bus-relative (0..n-1) device # */
290 		} destroy_device;	/* for CONTROLVM_DEVICE_DESTROY */
291 		/* for CONTROLVM_DEVICE_CONFIGURE */
292 		struct controlvm_packet_device_configure configure_device;
293 		struct  {
294 			u32 bus_no;	/* bus # (0..n-1) from the msg
295 					 * receiver's perspective */
296 			u32 dev_no;	/* bus-relative (0..n-1) device # */
297 		} reconfigure_device;	/* for CONTROLVM_DEVICE_RECONFIGURE */
298 		struct  {
299 			u32 bus_no;
300 			struct spar_segment_state state;
301 			u8 reserved[2];	/* Natural alignment purposes */
302 		} bus_change_state;	/* for CONTROLVM_BUS_CHANGESTATE */
303 		struct  {
304 			u32 bus_no;
305 			u32 dev_no;
306 			struct spar_segment_state state;
307 			struct  {
308 				u32 phys_device:1;	/* =1 if message is for
309 							 * a physical device */
310 			} flags;
311 			u8 reserved[2];	/* Natural alignment purposes */
312 		} device_change_state;	/* for CONTROLVM_DEVICE_CHANGESTATE */
313 		struct  {
314 			u32 bus_no;
315 			u32 dev_no;
316 			struct spar_segment_state state;
317 			u8 reserved[6];	/* Natural alignment purposes */
318 		} device_change_state_event;
319 			/* for CONTROLVM_DEVICE_CHANGESTATE_EVENT */
320 		struct  {
321 			u32 bus_count;	/* indicates the max number of busses */
322 			u32 switch_count; /* indicates the max number of
323 					   * switches if a service partition */
324 			enum ultra_chipset_feature features;
325 			u32 platform_number;	/* Platform Number */
326 		} init_chipset;	/* for CONTROLVM_CHIPSET_INIT */
327 		struct  {
328 			u32 options;	/* reserved */
329 			u32 test;	/* bit 0 set to run embedded selftest */
330 		} chipset_selftest;	/* for CONTROLVM_CHIPSET_SELFTEST */
331 		u64 addr;	/* a physical address of something, that can be
332 				 * dereferenced by the receiver of this
333 				 * ControlVm command (depends on command id) */
334 		u64 handle;	/* a handle of something (depends on command
335 				 * id) */
336 	};
337 };
338 
339 /* All messages in any ControlVm queue have this layout. */
340 struct controlvm_message {
341 	struct controlvm_message_header hdr;
342 	struct controlvm_message_packet cmd;
343 };
344 
345 struct device_map {
346 	GUEST_PHYSICAL_ADDRESS device_channel_address;
347 	u64 device_channel_size;
348 	u32 ca_index;
349 	u32 reserved;		/* natural alignment */
350 	u64 reserved2;		/* Align structure on 32-byte boundary */
351 };
352 
353 struct guest_devices  {
354 	struct device_map video_channel;
355 	struct device_map keyboard_channel;
356 	struct device_map network_channel;
357 	struct device_map storage_channel;
358 	struct device_map console_channel;
359 	u32 partition_index;
360 	u32 pad;
361 };
362 
363 struct spar_controlvm_channel_protocol {
364 	 struct channel_header header;
365 	 GUEST_PHYSICAL_ADDRESS gp_controlvm;	/* guest physical address of
366 						 * this channel */
367 	 GUEST_PHYSICAL_ADDRESS gp_partition_tables;/* guest physical address of
368 						     * partition tables */
369 	 GUEST_PHYSICAL_ADDRESS gp_diag_guest;	/* guest physical address of
370 						 * diagnostic channel */
371 	 GUEST_PHYSICAL_ADDRESS gp_boot_romdisk;/* guest phys addr of (read
372 						 * only) Boot ROM disk */
373 	 GUEST_PHYSICAL_ADDRESS gp_boot_ramdisk;/* guest phys addr of writable
374 						 * Boot RAM disk */
375 	 GUEST_PHYSICAL_ADDRESS gp_acpi_table;	/* guest phys addr of acpi
376 						 * table */
377 	 GUEST_PHYSICAL_ADDRESS gp_control_channel;/* guest phys addr of control
378 						    * channel */
379 	 GUEST_PHYSICAL_ADDRESS gp_diag_romdisk;/* guest phys addr of diagnostic
380 						 * ROM disk */
381 	 GUEST_PHYSICAL_ADDRESS gp_nvram;	/* guest phys addr of NVRAM
382 						 * channel */
383 	 u64 request_payload_offset;	/* Offset to request payload area */
384 	 u64 event_payload_offset;	/* Offset to event payload area */
385 	 u32 request_payload_bytes;	/* Bytes available in request payload
386 					 * area */
387 	 u32 event_payload_bytes;/* Bytes available in event payload area */
388 	 u32 control_channel_bytes;
389 	 u32 nvram_channel_bytes;	/* Bytes in PartitionNvram segment */
390 	 u32 message_bytes;	/* sizeof(CONTROLVM_MESSAGE) */
391 	 u32 message_count;	/* CONTROLVM_MESSAGE_MAX */
392 	 GUEST_PHYSICAL_ADDRESS gp_smbios_table;/* guest phys addr of SMBIOS
393 						 * tables */
394 	 GUEST_PHYSICAL_ADDRESS gp_physical_smbios_table;/* guest phys addr of
395 							  * SMBIOS table  */
396 	 /* ULTRA_MAX_GUESTS_PER_SERVICE */
397 	 struct guest_devices gp_obsolete_guest_devices[16];
398 
399 	 /* guest physical address of EFI firmware image base  */
400 	 GUEST_PHYSICAL_ADDRESS virtual_guest_firmware_image_base;
401 
402 	 /* guest physical address of EFI firmware entry point  */
403 	 GUEST_PHYSICAL_ADDRESS virtual_guest_firmware_entry_point;
404 
405 	 /* guest EFI firmware image size  */
406 	 u64 virtual_guest_firmware_image_size;
407 
408 	 /* GPA = 1MB where EFI firmware image is copied to  */
409 	 GUEST_PHYSICAL_ADDRESS virtual_guest_firmware_boot_base;
410 	 GUEST_PHYSICAL_ADDRESS virtual_guest_image_base;
411 	 GUEST_PHYSICAL_ADDRESS virtual_guest_image_size;
412 	 u64 prototype_control_channel_offset;
413 	 GUEST_PHYSICAL_ADDRESS virtual_guest_partition_handle;
414 
415 	 u16 restore_action;	/* Restore Action field to restore the guest
416 				 * partition */
417 	u16 dump_action;	/* For Windows guests it shows if the visordisk
418 				 * is running in dump mode */
419 	u16 nvram_fail_count;
420 	u16 saved_crash_message_count;	/* = CONTROLVM_CRASHMSG_MAX */
421 	u32 saved_crash_message_offset;	/* Offset to request payload area needed
422 					 * for crash dump */
423 	u32 installation_error;	/* Type of error encountered during
424 				 * installation */
425 	u32 installation_text_id;	/* Id of string to display */
426 	u16 installation_remaining_steps;/* Number of remaining installation
427 					  * steps (for progress bars) */
428 	u8 tool_action;		/* ULTRA_TOOL_ACTIONS Installation Action
429 				 * field */
430 	u8 reserved;		/* alignment */
431 	struct efi_spar_indication efi_spar_ind;
432 	struct efi_spar_indication efi_spar_ind_supported;
433 	u32 sp_reserved;
434 	u8 reserved2[28];	/* Force signals to begin on 128-byte cache
435 				 * line */
436 	struct signal_queue_header request_queue;/* Service or guest partition
437 						  * uses this queue to send
438 						  * requests to Control */
439 	struct signal_queue_header response_queue;/* Control uses this queue to
440 						   * respond to service or guest
441 						   * partition requests */
442 	struct signal_queue_header event_queue;	/* Control uses this queue to
443 						 * send events to service or
444 						 * guest partition */
445 	struct signal_queue_header event_ack_queue;/* Service or guest partition
446 						    * uses this queue to ack
447 						    * Control events */
448 
449 	 /* Request fixed-size message pool - does not include payload */
450 	 struct controlvm_message request_msg[CONTROLVM_MESSAGE_MAX];
451 
452 	 /* Response fixed-size message pool - does not include payload */
453 	 struct controlvm_message response_msg[CONTROLVM_MESSAGE_MAX];
454 
455 	 /* Event fixed-size message pool - does not include payload */
456 	 struct controlvm_message event_msg[CONTROLVM_MESSAGE_MAX];
457 
458 	 /* Ack fixed-size message pool - does not include payload */
459 	 struct controlvm_message event_ack_msg[CONTROLVM_MESSAGE_MAX];
460 
461 	 /* Message stored during IOVM creation to be reused after crash */
462 	 struct controlvm_message saved_crash_msg[CONTROLVM_CRASHMSG_MAX];
463 };
464 
465 /* Offsets for VM channel attributes... */
466 #define VM_CH_REQ_QUEUE_OFFSET \
467 	offsetof(struct spar_controlvm_channel_protocol, request_queue)
468 #define VM_CH_RESP_QUEUE_OFFSET \
469 	offsetof(struct spar_controlvm_channel_protocol, response_queue)
470 #define VM_CH_EVENT_QUEUE_OFFSET \
471 	offsetof(struct spar_controlvm_channel_protocol, event_queue)
472 #define VM_CH_ACK_QUEUE_OFFSET \
473 	offsetof(struct spar_controlvm_channel_protocol, event_ack_queue)
474 #define VM_CH_REQ_MSG_OFFSET \
475 	offsetof(struct spar_controlvm_channel_protocol, request_msg)
476 #define VM_CH_RESP_MSG_OFFSET \
477 	offsetof(struct spar_controlvm_channel_protocol, response_msg)
478 #define VM_CH_EVENT_MSG_OFFSET \
479 	offsetof(struct spar_controlvm_channel_protocol, event_msg)
480 #define VM_CH_ACK_MSG_OFFSET \
481 	offsetof(struct spar_controlvm_channel_protocol, event_ack_msg)
482 #define VM_CH_CRASH_MSG_OFFSET \
483 	offsetof(struct spar_controlvm_channel_protocol, saved_crash_msg)
484 
485 /* The following header will be located at the beginning of PayloadVmOffset for
486  * various ControlVm commands. The receiver of a ControlVm command with a
487  * PayloadVmOffset will dereference this address and then use connection_offset,
488  * initiator_offset, and target_offset to get the location of UTF-8 formatted
489  * strings that can be parsed to obtain command-specific information. The value
490  * of total_length should equal PayloadBytes. The format of the strings at
491  * PayloadVmOffset will take different forms depending on the message.
492  */
493 struct spar_controlvm_parameters_header {
494 	u32 total_length;
495 	u32 header_length;
496 	u32 connection_offset;
497 	u32 connection_length;
498 	u32 initiator_offset;
499 	u32 initiator_length;
500 	u32 target_offset;
501 	u32 target_length;
502 	u32 client_offset;
503 	u32 client_length;
504 	u32 name_offset;
505 	u32 name_length;
506 	uuid_le id;
507 	u32 revision;
508 	u32 reserved;		/* Natural alignment */
509 };
510 
511 #endif				/* __CONTROLVMCHANNEL_H__ */
512