xref: /titanic_41/usr/src/uts/sun4v/sys/vdsk_common.h (revision 4bff34e37def8a90f9194d81bc345c52ba20086a)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef	_VDSK_COMMON_H
28 #define	_VDSK_COMMON_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #ifdef __cplusplus
33 extern "C" {
34 #endif
35 
36 /*
37  * This header file contains the private LDoms Virtual Disk (vDisk) definitions
38  * common to both the server (vds) and the client (vdc)
39  */
40 
41 #include <sys/efi_partition.h>
42 #include <sys/machparam.h>
43 #include <sys/vtoc.h>
44 
45 #include <sys/ldc.h>
46 #include <sys/vio_common.h>
47 #include <sys/vio_mailbox.h>
48 
49 /*
50  * vDisk definitions
51  */
52 
53 /*
54  * The number of Descriptor Ring entries
55  *
56  * Constraints:
57  * 	- overall DRing size must be greater than 8K (MMU_PAGESIZE)
58  *	- overall DRing size should be 8K aligned (desirable but not enforced)
59  *	- DRing entry must be 8 byte aligned
60  */
61 #define	VD_DRING_LEN		512
62 
63 /*
64  *
65  */
66 #define	VD_DRING_ENTRY_SZ	(sizeof (vd_dring_entry_t) + 		\
67 		(sizeof (ldc_mem_cookie_t) * (VD_MAX_COOKIES - 1)))
68 
69 /*
70  * The maximum block size we can transmit using one Descriptor Ring entry
71  *
72  * Currently no FS uses more than 128K and it doesn't look like they
73  * will either as there is no perf gain to be had by larger values.
74  * ( see ZFS comment at definition of SPA_MAXBLOCKSIZE ).
75  *
76  * We choose 256K to give us some headroom.
77  */
78 #define	VD_MAX_BLOCK_SIZE	(256 * 1024)
79 
80 #define	VD_MAX_COOKIES		((VD_MAX_BLOCK_SIZE / PAGESIZE) + 1)
81 #define	VD_USEC_TIMEOUT		20000
82 #define	VD_LDC_IDS_PROP		"ldc-ids"
83 #define	VD_LDC_MTU		256
84 
85 /*
86  * Flags used by ioctl routines to indicate if a copyin/copyout is needed
87  */
88 #define	VD_COPYOUT		0x1
89 #define	VD_COPYIN		0x2
90 
91 /*
92  * vDisk operations on physical devices
93  */
94 #define	VD_OP_BREAD		0x01	/* Block Read */
95 #define	VD_OP_BWRITE		0x02	/* Block Write */
96 #define	VD_OP_FLUSH		0x03	/* Flush disk write cache contents */
97 #define	VD_OP_GET_WCE		0x04	/* Get disk W$ status */
98 #define	VD_OP_SET_WCE		0x05	/* Enable/Disable disk W$ */
99 #define	VD_OP_GET_VTOC		0x06	/* Get VTOC */
100 #define	VD_OP_SET_VTOC		0x07	/* Set VTOC */
101 #define	VD_OP_GET_DISKGEOM	0x08	/* Get disk geometry */
102 #define	VD_OP_SET_DISKGEOM	0x09	/* Set disk geometry */
103 #define	VD_OP_SCSICMD		0x0a	/* SCSI control command */
104 #define	VD_OP_GET_DEVID		0x0b	/* Get device id */
105 #define	VD_OP_GET_EFI 		0x0c	/* Get EFI */
106 #define	VD_OP_SET_EFI 		0x0d	/* Set EFI */
107 #define	VD_OP_RESET		0x0e	/* Reset disk */
108 #define	VD_OP_GET_ACCESS	0x0f	/* Get disk access */
109 #define	VD_OP_SET_ACCESS	0x10	/* Set disk access */
110 #define	VD_OP_GET_CAPACITY	0x11	/* Get disk capacity */
111 #define	VD_OP_MASK		0xFF	/* mask of all possible operations */
112 #define	VD_OP_COUNT		0x11	/* Number of operations */
113 
114 /*
115  * Status for the VD_OP_GET_ACCESS operation
116  */
117 #define	VD_ACCESS_DENIED	0x00	/* access is not allowed */
118 #define	VD_ACCESS_ALLOWED	0x01	/* access is allowed */
119 
120 /*
121  * Flags for the VD_OP_SET_ACCESS operation
122  */
123 #define	VD_ACCESS_SET_CLEAR	0x00	/* clear exclusive access rights */
124 #define	VD_ACCESS_SET_EXCLUSIVE	0x01	/* set exclusive access rights */
125 #define	VD_ACCESS_SET_PREEMPT	0x02	/* forcefully set access rights */
126 #define	VD_ACCESS_SET_PRESERVE	0x04	/* preserve access rights */
127 
128 /*
129  * This is a mask of all the basic operations supported by all
130  * disk types (v1.0).
131  */
132 #define	VD_OP_MASK_READ			\
133 	((1 << VD_OP_BREAD) |			\
134 	(1 << VD_OP_GET_WCE) |			\
135 	(1 << VD_OP_GET_VTOC) |			\
136 	(1 << VD_OP_GET_DISKGEOM) |		\
137 	(1 << VD_OP_GET_DEVID) |		\
138 	(1 << VD_OP_GET_EFI))
139 
140 #define	VD_OP_MASK_WRITE			\
141 	((1 << VD_OP_BWRITE) |			\
142 	(1 << VD_OP_FLUSH) |			\
143 	(1 << VD_OP_SET_WCE) |			\
144 	(1 << VD_OP_SET_VTOC) |			\
145 	(1 << VD_OP_SET_DISKGEOM) |		\
146 	(1 << VD_OP_SET_EFI))
147 
148 /*
149  * Mask for additional operations provided for SCSI disks (v1.1)
150  */
151 #define	VD_OP_MASK_SCSI				\
152 	((1 << VD_OP_SCSICMD) |			\
153 	(1 << VD_OP_RESET) |			\
154 	(1 << VD_OP_GET_ACCESS) |		\
155 	(1 << VD_OP_SET_ACCESS) |		\
156 	(1 << VD_OP_GET_CAPACITY))
157 
158 /*
159  * macro to check if the operation 'op' is supported by checking the list
160  * of operations supported which is exported by the vDisk server.
161  */
162 #define	VD_OP_SUPPORTED(ops_bitmask, op)	((ops_bitmask) & (1 << (op)))
163 
164 /*
165  * Slice for absolute disk transaction.
166  */
167 #define	VD_SLICE_NONE		0xFF
168 
169 /*
170  * EFI disks do not have a slice 7. Actually that slice is used to represent
171  * the whole disk.
172  */
173 #define	VD_EFI_WD_SLICE	7
174 
175 /*
176  * Definitions of the various ways vds can export disk support to vdc.
177  */
178 typedef enum vd_disk_type {
179 	VD_DISK_TYPE_UNK = 0,		/* Unknown device type */
180 	VD_DISK_TYPE_SLICE,		/* slice in block device */
181 	VD_DISK_TYPE_DISK		/* entire disk (slice 2) */
182 } vd_disk_type_t;
183 
184 /*
185  * Definitions of the various disk label that vDisk supports.
186  */
187 typedef enum vd_disk_label {
188 	VD_DISK_LABEL_UNK = 0,		/* Unknown disk label */
189 	VD_DISK_LABEL_VTOC,		/* VTOC disk label */
190 	VD_DISK_LABEL_EFI		/* EFI disk label */
191 } vd_disk_label_t;
192 
193 /*
194  * vDisk Descriptor payload
195  */
196 typedef struct vd_dring_payload {
197 	uint64_t	req_id;		/* The request ID being processed */
198 	uint8_t		operation;	/* operation for server to perform */
199 	uint8_t		slice;		/* The disk slice being accessed */
200 	uint16_t	resv1;		/* padding */
201 	uint32_t	status;		/* "errno" of server operation */
202 	uint64_t	addr;		/* LP64	diskaddr_t (block I/O) */
203 	uint64_t	nbytes;		/* LP64 size_t */
204 	uint32_t	ncookies;	/* Number of cookies used */
205 	uint32_t	resv2;		/* padding */
206 
207 	ldc_mem_cookie_t	cookie[1];	/* variable sized array */
208 } vd_dring_payload_t;
209 
210 
211 /*
212  * vDisk Descriptor entry
213  */
214 typedef struct vd_dring_entry {
215 	vio_dring_entry_hdr_t		hdr;		/* common header */
216 	vd_dring_payload_t		payload;	/* disk specific data */
217 } vd_dring_entry_t;
218 
219 /*
220  * vDisk logical partition
221  */
222 typedef struct vd_slice {
223 	daddr_t	start;		/* block number of slice start */
224 	daddr_t nblocks;	/* number of blocks in the slice */
225 } vd_slice_t;
226 
227 
228 /*
229  * vDisk control operation structures
230  */
231 
232 /*
233  * vDisk geometry definition (VD_OP_GET_DISKGEOM and VD_OP_SET_DISKGEOM)
234  */
235 typedef struct vd_geom {
236 	uint16_t	ncyl;		/* number of data cylinders */
237 	uint16_t	acyl;		/* number of alternate cylinders */
238 	uint16_t	bcyl;		/* cyl offset for fixed head area */
239 	uint16_t	nhead;		/* number of heads */
240 	uint16_t	nsect;		/* number of data sectors per track */
241 	uint16_t	intrlv;		/* interleave factor */
242 	uint16_t	apc;		/* alternates per cyl (SCSI only) */
243 	uint16_t	rpm;		/* revolutions per minute */
244 	uint16_t	pcyl;		/* number of physical cylinders */
245 	uint16_t	write_reinstruct;	/* # sectors to skip, writes */
246 	uint16_t	read_reinstruct;	/* # sectors to skip, reads */
247 } vd_geom_t;
248 
249 
250 /*
251  * vDisk partition definition
252  */
253 typedef struct vd_partition {
254 	uint16_t	id_tag;		/* ID tag of partition */
255 	uint16_t	perm;		/* permission flags for partition */
256 	uint32_t	reserved;	/* padding */
257 	uint64_t	start;		/* block number of partition start */
258 	uint64_t	nblocks;	/* number of blocks in partition */
259 } vd_partition_t;
260 
261 /*
262  * vDisk VTOC definition (VD_OP_GET_VTOC and VD_OP_SET_VTOC)
263  */
264 #define	VD_VOLNAME_LEN		8	/* length of volume_name field */
265 #define	VD_ASCIILABEL_LEN	128	/* length of ascii_label field */
266 typedef struct vd_vtoc {
267 	char		volume_name[VD_VOLNAME_LEN];	/* volume name */
268 	uint16_t	sector_size;		/* sector size in bytes */
269 	uint16_t	num_partitions;		/* number of partitions */
270 	char		ascii_label[VD_ASCIILABEL_LEN];	/* ASCII label */
271 	vd_partition_t	partition[V_NUMPAR];	/* partition headers */
272 } vd_vtoc_t;
273 
274 
275 /*
276  * vDisk EFI definition (VD_OP_GET_EFI and VD_OP_SET_EFI)
277  */
278 typedef struct vd_efi {
279 	uint64_t	lba;		/* lba of the request */
280 	uint64_t	length;		/* length of data */
281 	char		data[1];	/* data of the request */
282 } vd_efi_t;
283 
284 
285 /*
286  * vDisk DEVID definition (VD_OP_GET_DEVID)
287  */
288 #define	VD_DEVID_SIZE(l)	(sizeof (vd_devid_t) - 1 + l)
289 #define	VD_DEVID_DEFAULT_LEN	128
290 
291 typedef struct vd_devid {
292 	uint16_t	reserved;	/* padding */
293 	uint16_t	type;		/* type of device id */
294 	uint32_t	length;		/* length the device id */
295 	char		id[1];		/* device id */
296 } vd_devid_t;
297 
298 /*
299  * vDisk CAPACITY definition (VD_OP_GET_CAPACITY)
300  */
301 typedef struct vd_capacity {
302 	uint32_t	vdisk_block_size;	/* block size in bytes */
303 	uint32_t	reserved;		/* reserved */
304 	uint64_t	vdisk_size;		/* disk size in blocks */
305 } vd_capacity_t;
306 
307 /* Identifier for unknown disk size */
308 #define	VD_SIZE_UNKNOWN		-1
309 
310 /*
311  * vDisk SCSI definition (VD_OP_SCSICMD)
312  */
313 typedef struct vd_scsi {
314 	uint8_t		cmd_status;	/* command completion status */
315 	uint8_t		sense_status;	/* sense command completion status */
316 	uint8_t		task_attribute;	/* task attribute */
317 	uint8_t		task_priority;	/* task priority */
318 	uint8_t		crn;		/* command reference number */
319 	uint8_t		reserved;	/* reserved */
320 	uint16_t	timeout;	/* command timeout */
321 	uint64_t	options;	/* options */
322 	uint64_t	cdb_len;	/* CDB data length */
323 	uint64_t	sense_len;	/* sense request length */
324 	uint64_t	datain_len;	/* data in buffer length */
325 	uint64_t	dataout_len;	/* data out buffer length */
326 	char		data[1];	/* data (CDB, sense, data in/out */
327 } vd_scsi_t;
328 
329 /* Minimum size of the vd_scsi structure */
330 #define	VD_SCSI_SIZE	(sizeof (vd_scsi_t) - sizeof (uint64_t))
331 
332 /*
333  * Macros to access data buffers in a vd_scsi structure. When using these
334  * macros, the vd_scsi structure needs to be populated with the sizes of
335  * data buffers allocated in the structure.
336  */
337 #define	VD_SCSI_DATA_CDB(vscsi)		\
338 	((union scsi_cdb *)(uintptr_t)((vscsi)->data))
339 
340 #define	VD_SCSI_DATA_SENSE(vscsi) 	\
341 	((struct scsi_extended_sense *)(uintptr_t)((vscsi)->data + \
342 	    P2ROUNDUP((vscsi)->cdb_len, sizeof (uint64_t))))
343 
344 #define	VD_SCSI_DATA_IN(vscsi)		\
345 	((uintptr_t)((vscsi)->data +	\
346 	    P2ROUNDUP((vscsi)->cdb_len, sizeof (uint64_t)) + 	\
347 	    P2ROUNDUP((vscsi)->sense_len, sizeof (uint64_t))))
348 
349 #define	VD_SCSI_DATA_OUT(vscsi)		\
350 	((uintptr_t)((vscsi)->data +	\
351 	    P2ROUNDUP((vscsi)->cdb_len, sizeof (uint64_t)) + 	\
352 	    P2ROUNDUP((vscsi)->sense_len, sizeof (uint64_t)) + 	\
353 	    P2ROUNDUP((vscsi)->datain_len, sizeof (uint64_t))))
354 
355 /* vDisk SCSI task attribute */
356 #define	VD_SCSI_TASK_SIMPLE	0x01	/* simple task */
357 #define	VD_SCSI_TASK_ORDERED	0x02	/* ordered task */
358 #define	VD_SCSI_TASK_HQUEUE	0x03	/* head of queue task */
359 #define	VD_SCSI_TASK_ACA	0x04	/* ACA task */
360 
361 /* vDisk SCSI options */
362 #define	VD_SCSI_OPT_CRN		0x01	/* request has a CRN */
363 #define	VD_SCSI_OPT_NORETRY	0x02	/* do not attempt any retry */
364 
365 /*
366  * Copy the contents of a vd_geom_t to the contents of a dk_geom struct
367  */
368 #define	VD_GEOM2DK_GEOM(vd_geom, dk_geom)				\
369 {									\
370 	bzero((dk_geom), sizeof (*(dk_geom)));				\
371 	(dk_geom)->dkg_ncyl		= (vd_geom)->ncyl;		\
372 	(dk_geom)->dkg_acyl		= (vd_geom)->acyl;		\
373 	(dk_geom)->dkg_bcyl		= (vd_geom)->bcyl;		\
374 	(dk_geom)->dkg_nhead		= (vd_geom)->nhead;		\
375 	(dk_geom)->dkg_nsect		= (vd_geom)->nsect;		\
376 	(dk_geom)->dkg_intrlv		= (vd_geom)->intrlv;		\
377 	(dk_geom)->dkg_apc		= (vd_geom)->apc;		\
378 	(dk_geom)->dkg_rpm		= (vd_geom)->rpm;		\
379 	(dk_geom)->dkg_pcyl		= (vd_geom)->pcyl;		\
380 	(dk_geom)->dkg_write_reinstruct	= (vd_geom)->write_reinstruct;	\
381 	(dk_geom)->dkg_read_reinstruct	= (vd_geom)->read_reinstruct;	\
382 }
383 
384 /*
385  * Copy the contents of a vd_vtoc_t to the contents of a vtoc struct
386  */
387 #define	VD_VTOC2VTOC(vd_vtoc, vtoc)					\
388 {									\
389 	bzero((vtoc), sizeof (*(vtoc)));				\
390 	bcopy((vd_vtoc)->volume_name, (vtoc)->v_volume,			\
391 	    MIN(sizeof ((vd_vtoc)->volume_name),			\
392 		sizeof ((vtoc)->v_volume)));				\
393 	bcopy((vd_vtoc)->ascii_label, (vtoc)->v_asciilabel,		\
394 	    MIN(sizeof ((vd_vtoc)->ascii_label),			\
395 		sizeof ((vtoc)->v_asciilabel)));			\
396 	(vtoc)->v_sanity	= VTOC_SANE;				\
397 	(vtoc)->v_version	= V_VERSION;				\
398 	(vtoc)->v_sectorsz	= (vd_vtoc)->sector_size;		\
399 	(vtoc)->v_nparts	= (vd_vtoc)->num_partitions;		\
400 	for (int i = 0; i < (vd_vtoc)->num_partitions; i++) {		\
401 		(vtoc)->v_part[i].p_tag	= (vd_vtoc)->partition[i].id_tag; \
402 		(vtoc)->v_part[i].p_flag = (vd_vtoc)->partition[i].perm; \
403 		(vtoc)->v_part[i].p_start = (vd_vtoc)->partition[i].start; \
404 		(vtoc)->v_part[i].p_size = (vd_vtoc)->partition[i].nblocks; \
405 	}								\
406 }
407 
408 /*
409  * Copy the contents of a dk_geom struct to the contents of a vd_geom_t
410  */
411 #define	DK_GEOM2VD_GEOM(dk_geom, vd_geom)				\
412 {									\
413 	bzero((vd_geom), sizeof (*(vd_geom)));				\
414 	(vd_geom)->ncyl			= (dk_geom)->dkg_ncyl;		\
415 	(vd_geom)->acyl			= (dk_geom)->dkg_acyl;		\
416 	(vd_geom)->bcyl			= (dk_geom)->dkg_bcyl;		\
417 	(vd_geom)->nhead		= (dk_geom)->dkg_nhead;		\
418 	(vd_geom)->nsect		= (dk_geom)->dkg_nsect;		\
419 	(vd_geom)->intrlv		= (dk_geom)->dkg_intrlv;	\
420 	(vd_geom)->apc			= (dk_geom)->dkg_apc;		\
421 	(vd_geom)->rpm			= (dk_geom)->dkg_rpm;		\
422 	(vd_geom)->pcyl			= (dk_geom)->dkg_pcyl;		\
423 	(vd_geom)->write_reinstruct	= (dk_geom)->dkg_write_reinstruct; \
424 	(vd_geom)->read_reinstruct	= (dk_geom)->dkg_read_reinstruct; \
425 }
426 
427 /*
428  * Copy the contents of a vtoc struct to the contents of a vd_vtoc_t
429  */
430 #define	VTOC2VD_VTOC(vtoc, vd_vtoc)					\
431 {									\
432 	bzero((vd_vtoc), sizeof (*(vd_vtoc)));				\
433 	bcopy((vtoc)->v_volume, (vd_vtoc)->volume_name,			\
434 	    MIN(sizeof ((vtoc)->v_volume),				\
435 		sizeof ((vd_vtoc)->volume_name)));			\
436 	bcopy((vtoc)->v_asciilabel, (vd_vtoc)->ascii_label,		\
437 	    MIN(sizeof ((vtoc)->v_asciilabel),				\
438 		sizeof ((vd_vtoc)->ascii_label)));			\
439 	(vd_vtoc)->sector_size			= (vtoc)->v_sectorsz;	\
440 	(vd_vtoc)->num_partitions		= (vtoc)->v_nparts;	\
441 	for (int i = 0; i < (vtoc)->v_nparts; i++) {			\
442 		(vd_vtoc)->partition[i].id_tag	= (vtoc)->v_part[i].p_tag; \
443 		(vd_vtoc)->partition[i].perm	= (vtoc)->v_part[i].p_flag; \
444 		(vd_vtoc)->partition[i].start	= (vtoc)->v_part[i].p_start; \
445 		(vd_vtoc)->partition[i].nblocks	= (vtoc)->v_part[i].p_size; \
446 	}								\
447 }
448 
449 /*
450  * Copy the contents of a vd_efi_t to the contents of a dk_efi_t.
451  * Note that (dk_efi)->dki_data and (vd_efi)->data should be correctly
452  * initialized prior to using this macro.
453  */
454 #define	VD_EFI2DK_EFI(vd_efi, dk_efi)					\
455 {									\
456 	(dk_efi)->dki_lba	= (vd_efi)->lba;			\
457 	(dk_efi)->dki_length	= (vd_efi)->length;			\
458 	bcopy((vd_efi)->data, (dk_efi)->dki_data, (dk_efi)->dki_length); \
459 }
460 
461 /*
462  * Copy the contents of dk_efi_t to the contents of vd_efi_t.
463  * Note that (dk_efi)->dki_data and (vd_efi)->data should be correctly
464  * initialized prior to using this macro.
465  */
466 #define	DK_EFI2VD_EFI(dk_efi, vd_efi)					\
467 {									\
468 	(vd_efi)->lba		= (dk_efi)->dki_lba;			\
469 	(vd_efi)->length	= (dk_efi)->dki_length;			\
470 	bcopy((dk_efi)->dki_data, (vd_efi)->data, (vd_efi)->length);	\
471 }
472 
473 #define	VD_MEDIATYPE2DK_MEDIATYPE(mt)					\
474 	((mt) == VD_MEDIA_FIXED ? DK_FIXED_DISK :			\
475 	    (mt) == VD_MEDIA_CD ? DK_CDROM :				\
476 	    (mt) == VD_MEDIA_DVD ? DK_DVDROM :				\
477 	    DK_UNKNOWN)
478 
479 #define	DK_MEDIATYPE2VD_MEDIATYPE(mt)					\
480 	((mt) == DK_REMOVABLE_DISK ? VD_MEDIA_FIXED :			\
481 	    (mt) == DK_MO_ERASABLE ? VD_MEDIA_FIXED :			\
482 	    (mt) == DK_MO_WRITEONCE ? VD_MEDIA_FIXED :			\
483 	    (mt) == DK_AS_MO ? VD_MEDIA_FIXED :				\
484 	    (mt) == DK_CDROM ? VD_MEDIA_CD :				\
485 	    (mt) == DK_CDR ? VD_MEDIA_CD :				\
486 	    (mt) == DK_CDRW ? VD_MEDIA_CD :				\
487 	    (mt) == DK_DVDROM ? VD_MEDIA_DVD :				\
488 	    (mt) == DK_DVDR ? VD_MEDIA_DVD :				\
489 	    (mt) == DK_DVDRAM ? VD_MEDIA_DVD :				\
490 	    (mt) == DK_FIXED_DISK ? VD_MEDIA_FIXED :			\
491 	    (mt) == DK_FLOPPY ? VD_MEDIA_FIXED :			\
492 	    (mt) == DK_ZIP ? VD_MEDIA_FIXED :				\
493 	    (mt) == DK_JAZ ? VD_MEDIA_FIXED :				\
494 	    VD_MEDIA_FIXED)
495 
496 /*
497  * Hooks for EFI support
498  */
499 
500 /*
501  * The EFI alloc_and_read() function will use some ioctls to get EFI data
502  * but the device reference we will use is different depending if the command
503  * is issued from the vDisk server side (vds) or from the vDisk client side
504  * (vdc). The vd_efi_dev structure is filled by vdc/vds to indicate the ioctl
505  * function to call back and to provide information about the virtual disk.
506  */
507 typedef int (*vd_efi_ioctl_func)(void *, int, uintptr_t);
508 
509 typedef	struct vd_efi_dev {
510 	void *vdisk;			/* opaque pointer to the vdisk */
511 	size_t block_size;		/* vdisk block size */
512 	size_t disk_size;		/* vdisk size in blocks */
513 	vd_efi_ioctl_func vdisk_ioctl;	/* vdisk ioctl function */
514 } vd_efi_dev_t;
515 
516 #define	VD_EFI_DEV_SET(efi_dev, vdsk, ioctl)		\
517 	(efi_dev).vdisk = vdsk;				\
518 	(efi_dev).vdisk_ioctl = ioctl;			\
519 	(efi_dev).block_size = (vdsk)->block_size;	\
520 	(efi_dev).disk_size = (vdsk)->vdisk_size;
521 
522 
523 int vd_efi_alloc_and_read(vd_efi_dev_t *dev, efi_gpt_t **gpt, efi_gpe_t **gpe);
524 void vd_efi_free(vd_efi_dev_t *dev, efi_gpt_t *gpt, efi_gpe_t *gpe);
525 
526 
527 #ifdef	__cplusplus
528 }
529 #endif
530 
531 #endif	/* _VDSK_COMMON_H */
532