xref: /titanic_41/usr/src/uts/sun4v/io/vdc.c (revision 10569901907c93e3fa20f6ac0b589b9a5b869a80)
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 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * LDoms virtual disk client (vdc) device driver
31  *
32  * This driver runs on a guest logical domain and communicates with the virtual
33  * disk server (vds) driver running on the service domain which is exporting
34  * virtualized "disks" to the guest logical domain.
35  *
36  * The driver can be divided into four sections:
37  *
38  * 1) generic device driver housekeeping
39  *	_init, _fini, attach, detach, ops structures, etc.
40  *
41  * 2) communication channel setup
42  *	Setup the communications link over the LDC channel that vdc uses to
43  *	talk to the vDisk server. Initialise the descriptor ring which
44  *	allows the LDC clients to transfer data via memory mappings.
45  *
46  * 3) Support exported to upper layers (filesystems, etc)
47  *	The upper layers call into vdc via strategy(9E) and DKIO(7I)
48  *	ioctl calls. vdc will copy the data to be written to the descriptor
49  *	ring or maps the buffer to store the data read by the vDisk
50  *	server into the descriptor ring. It then sends a message to the
51  *	vDisk server requesting it to complete the operation.
52  *
53  * 4) Handling responses from vDisk server.
54  *	The vDisk server will ACK some or all of the messages vdc sends to it
55  *	(this is configured during the handshake). Upon receipt of an ACK
56  *	vdc will check the descriptor ring and signal to the upper layer
57  *	code waiting on the IO.
58  */
59 
60 #include <sys/atomic.h>
61 #include <sys/conf.h>
62 #include <sys/disp.h>
63 #include <sys/ddi.h>
64 #include <sys/dkio.h>
65 #include <sys/efi_partition.h>
66 #include <sys/fcntl.h>
67 #include <sys/file.h>
68 #include <sys/mach_descrip.h>
69 #include <sys/modctl.h>
70 #include <sys/mdeg.h>
71 #include <sys/note.h>
72 #include <sys/open.h>
73 #include <sys/sdt.h>
74 #include <sys/stat.h>
75 #include <sys/sunddi.h>
76 #include <sys/types.h>
77 #include <sys/promif.h>
78 #include <sys/var.h>
79 #include <sys/vtoc.h>
80 #include <sys/archsystm.h>
81 #include <sys/sysmacros.h>
82 
83 #include <sys/cdio.h>
84 #include <sys/dktp/fdisk.h>
85 #include <sys/dktp/dadkio.h>
86 #include <sys/mhd.h>
87 #include <sys/scsi/generic/sense.h>
88 #include <sys/scsi/impl/uscsi.h>
89 #include <sys/scsi/impl/services.h>
90 #include <sys/scsi/targets/sddef.h>
91 
92 #include <sys/ldoms.h>
93 #include <sys/ldc.h>
94 #include <sys/vio_common.h>
95 #include <sys/vio_mailbox.h>
96 #include <sys/vio_util.h>
97 #include <sys/vdsk_common.h>
98 #include <sys/vdsk_mailbox.h>
99 #include <sys/vdc.h>
100 
101 /*
102  * function prototypes
103  */
104 
105 /* standard driver functions */
106 static int	vdc_open(dev_t *dev, int flag, int otyp, cred_t *cred);
107 static int	vdc_close(dev_t dev, int flag, int otyp, cred_t *cred);
108 static int	vdc_strategy(struct buf *buf);
109 static int	vdc_print(dev_t dev, char *str);
110 static int	vdc_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk);
111 static int	vdc_read(dev_t dev, struct uio *uio, cred_t *cred);
112 static int	vdc_write(dev_t dev, struct uio *uio, cred_t *cred);
113 static int	vdc_ioctl(dev_t dev, int cmd, intptr_t arg, int mode,
114 			cred_t *credp, int *rvalp);
115 static int	vdc_aread(dev_t dev, struct aio_req *aio, cred_t *cred);
116 static int	vdc_awrite(dev_t dev, struct aio_req *aio, cred_t *cred);
117 
118 static int	vdc_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd,
119 			void *arg, void **resultp);
120 static int	vdc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
121 static int	vdc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);
122 
123 /* setup */
124 static void	vdc_min(struct buf *bufp);
125 static int	vdc_send(vdc_t *vdc, caddr_t pkt, size_t *msglen);
126 static int	vdc_do_ldc_init(vdc_t *vdc, md_t *mdp, mde_cookie_t vd_node);
127 static int	vdc_start_ldc_connection(vdc_t *vdc);
128 static int	vdc_create_device_nodes(vdc_t *vdc);
129 static int	vdc_create_device_nodes_efi(vdc_t *vdc);
130 static int	vdc_create_device_nodes_vtoc(vdc_t *vdc);
131 static int	vdc_create_device_nodes_props(vdc_t *vdc);
132 static int	vdc_get_md_node(dev_info_t *dip, md_t **mdpp,
133 		    mde_cookie_t *vd_nodep, mde_cookie_t *vd_portp);
134 static int	vdc_get_ldc_id(md_t *, mde_cookie_t, uint64_t *);
135 static int	vdc_do_ldc_up(vdc_t *vdc);
136 static void	vdc_terminate_ldc(vdc_t *vdc);
137 static int	vdc_init_descriptor_ring(vdc_t *vdc);
138 static void	vdc_destroy_descriptor_ring(vdc_t *vdc);
139 static int	vdc_setup_devid(vdc_t *vdc);
140 static void	vdc_store_label_efi(vdc_t *vdc, struct dk_gpt *efi);
141 static void	vdc_store_label_vtoc(vdc_t *, struct dk_geom *, struct vtoc *);
142 static void	vdc_store_label_unk(vdc_t *vdc);
143 static boolean_t vdc_is_opened(vdc_t *vdc);
144 
145 /* handshake with vds */
146 static int		vdc_init_ver_negotiation(vdc_t *vdc, vio_ver_t ver);
147 static int		vdc_ver_negotiation(vdc_t *vdcp);
148 static int		vdc_init_attr_negotiation(vdc_t *vdc);
149 static int		vdc_attr_negotiation(vdc_t *vdcp);
150 static int		vdc_init_dring_negotiate(vdc_t *vdc);
151 static int		vdc_dring_negotiation(vdc_t *vdcp);
152 static int		vdc_send_rdx(vdc_t *vdcp);
153 static int		vdc_rdx_exchange(vdc_t *vdcp);
154 static boolean_t	vdc_is_supported_version(vio_ver_msg_t *ver_msg);
155 
156 /* processing incoming messages from vDisk server */
157 static void	vdc_process_msg_thread(vdc_t *vdc);
158 static int	vdc_recv(vdc_t *vdc, vio_msg_t *msgp, size_t *nbytesp);
159 
160 static uint_t	vdc_handle_cb(uint64_t event, caddr_t arg);
161 static int	vdc_process_data_msg(vdc_t *vdc, vio_msg_t *msg);
162 static int	vdc_handle_ver_msg(vdc_t *vdc, vio_ver_msg_t *ver_msg);
163 static int	vdc_handle_attr_msg(vdc_t *vdc, vd_attr_msg_t *attr_msg);
164 static int	vdc_handle_dring_reg_msg(vdc_t *vdc, vio_dring_reg_msg_t *msg);
165 static int 	vdc_send_request(vdc_t *vdcp, int operation,
166 		    caddr_t addr, size_t nbytes, int slice, diskaddr_t offset,
167 		    int cb_type, void *cb_arg, vio_desc_direction_t dir);
168 static int	vdc_map_to_shared_dring(vdc_t *vdcp, int idx);
169 static int 	vdc_populate_descriptor(vdc_t *vdcp, int operation,
170 		    caddr_t addr, size_t nbytes, int slice, diskaddr_t offset,
171 		    int cb_type, void *cb_arg, vio_desc_direction_t dir);
172 static int 	vdc_do_sync_op(vdc_t *vdcp, int operation, caddr_t addr,
173 		    size_t nbytes, int slice, diskaddr_t offset, int cb_type,
174 		    void *cb_arg, vio_desc_direction_t dir, boolean_t);
175 
176 static int	vdc_wait_for_response(vdc_t *vdcp, vio_msg_t *msgp);
177 static int	vdc_drain_response(vdc_t *vdcp);
178 static int	vdc_depopulate_descriptor(vdc_t *vdc, uint_t idx);
179 static int	vdc_populate_mem_hdl(vdc_t *vdcp, vdc_local_desc_t *ldep);
180 static int	vdc_verify_seq_num(vdc_t *vdc, vio_dring_msg_t *dring_msg);
181 
182 /* dkio */
183 static int	vd_process_ioctl(dev_t dev, int cmd, caddr_t arg, int mode,
184 		    int *rvalp);
185 static int	vd_process_efi_ioctl(dev_t dev, int cmd, caddr_t arg, int mode);
186 static void	vdc_create_fake_geometry(vdc_t *vdc);
187 static int	vdc_validate_geometry(vdc_t *vdc);
188 static void	vdc_validate(vdc_t *vdc);
189 static void	vdc_validate_task(void *arg);
190 static int	vdc_null_copy_func(vdc_t *vdc, void *from, void *to,
191 		    int mode, int dir);
192 static int	vdc_get_wce_convert(vdc_t *vdc, void *from, void *to,
193 		    int mode, int dir);
194 static int	vdc_set_wce_convert(vdc_t *vdc, void *from, void *to,
195 		    int mode, int dir);
196 static int	vdc_get_vtoc_convert(vdc_t *vdc, void *from, void *to,
197 		    int mode, int dir);
198 static int	vdc_set_vtoc_convert(vdc_t *vdc, void *from, void *to,
199 		    int mode, int dir);
200 static int	vdc_get_geom_convert(vdc_t *vdc, void *from, void *to,
201 		    int mode, int dir);
202 static int	vdc_set_geom_convert(vdc_t *vdc, void *from, void *to,
203 		    int mode, int dir);
204 static int	vdc_get_efi_convert(vdc_t *vdc, void *from, void *to,
205 		    int mode, int dir);
206 static int	vdc_set_efi_convert(vdc_t *vdc, void *from, void *to,
207 		    int mode, int dir);
208 
209 static void 	vdc_ownership_update(vdc_t *vdc, int ownership_flags);
210 static int	vdc_access_set(vdc_t *vdc, uint64_t flags, int mode);
211 static vdc_io_t	*vdc_failfast_io_queue(vdc_t *vdc, struct buf *buf);
212 static int	vdc_failfast_check_resv(vdc_t *vdc);
213 
214 /*
215  * Module variables
216  */
217 
218 /*
219  * Tunable variables to control how long vdc waits before timing out on
220  * various operations
221  */
222 static int	vdc_hshake_retries = 3;
223 
224 static int	vdc_timeout = 0; /* units: seconds */
225 
226 static uint64_t vdc_hz_min_ldc_delay;
227 static uint64_t vdc_min_timeout_ldc = 1 * MILLISEC;
228 static uint64_t vdc_hz_max_ldc_delay;
229 static uint64_t vdc_max_timeout_ldc = 100 * MILLISEC;
230 
231 static uint64_t vdc_ldc_read_init_delay = 1 * MILLISEC;
232 static uint64_t vdc_ldc_read_max_delay = 100 * MILLISEC;
233 
234 /* values for dumping - need to run in a tighter loop */
235 static uint64_t	vdc_usec_timeout_dump = 100 * MILLISEC;	/* 0.1s units: ns */
236 static int	vdc_dump_retries = 100;
237 
238 static uint16_t	vdc_scsi_timeout = 60;	/* 60s units: seconds  */
239 
240 static uint64_t vdc_ownership_delay = 6 * MICROSEC; /* 6s units: usec */
241 
242 /* Count of the number of vdc instances attached */
243 static volatile uint32_t	vdc_instance_count = 0;
244 
245 /* Tunable to log all SCSI errors */
246 static boolean_t vdc_scsi_log_error = B_FALSE;
247 
248 /* Soft state pointer */
249 static void	*vdc_state;
250 
251 /*
252  * Controlling the verbosity of the error/debug messages
253  *
254  * vdc_msglevel - controls level of messages
255  * vdc_matchinst - 64-bit variable where each bit corresponds
256  *                 to the vdc instance the vdc_msglevel applies.
257  */
258 int		vdc_msglevel = 0x0;
259 uint64_t	vdc_matchinst = 0ull;
260 
261 /*
262  * Supported vDisk protocol version pairs.
263  *
264  * The first array entry is the latest and preferred version.
265  */
266 static const vio_ver_t	vdc_version[] = {{1, 1}};
267 
268 static struct cb_ops vdc_cb_ops = {
269 	vdc_open,	/* cb_open */
270 	vdc_close,	/* cb_close */
271 	vdc_strategy,	/* cb_strategy */
272 	vdc_print,	/* cb_print */
273 	vdc_dump,	/* cb_dump */
274 	vdc_read,	/* cb_read */
275 	vdc_write,	/* cb_write */
276 	vdc_ioctl,	/* cb_ioctl */
277 	nodev,		/* cb_devmap */
278 	nodev,		/* cb_mmap */
279 	nodev,		/* cb_segmap */
280 	nochpoll,	/* cb_chpoll */
281 	ddi_prop_op,	/* cb_prop_op */
282 	NULL,		/* cb_str */
283 	D_MP | D_64BIT,	/* cb_flag */
284 	CB_REV,		/* cb_rev */
285 	vdc_aread,	/* cb_aread */
286 	vdc_awrite	/* cb_awrite */
287 };
288 
289 static struct dev_ops vdc_ops = {
290 	DEVO_REV,	/* devo_rev */
291 	0,		/* devo_refcnt */
292 	vdc_getinfo,	/* devo_getinfo */
293 	nulldev,	/* devo_identify */
294 	nulldev,	/* devo_probe */
295 	vdc_attach,	/* devo_attach */
296 	vdc_detach,	/* devo_detach */
297 	nodev,		/* devo_reset */
298 	&vdc_cb_ops,	/* devo_cb_ops */
299 	NULL,		/* devo_bus_ops */
300 	nulldev		/* devo_power */
301 };
302 
303 static struct modldrv modldrv = {
304 	&mod_driverops,
305 	"virtual disk client",
306 	&vdc_ops,
307 };
308 
309 static struct modlinkage modlinkage = {
310 	MODREV_1,
311 	&modldrv,
312 	NULL
313 };
314 
315 /* -------------------------------------------------------------------------- */
316 
317 /*
318  * Device Driver housekeeping and setup
319  */
320 
321 int
322 _init(void)
323 {
324 	int	status;
325 
326 	if ((status = ddi_soft_state_init(&vdc_state, sizeof (vdc_t), 1)) != 0)
327 		return (status);
328 	if ((status = mod_install(&modlinkage)) != 0)
329 		ddi_soft_state_fini(&vdc_state);
330 	vdc_efi_init(vd_process_efi_ioctl);
331 	return (status);
332 }
333 
334 int
335 _info(struct modinfo *modinfop)
336 {
337 	return (mod_info(&modlinkage, modinfop));
338 }
339 
340 int
341 _fini(void)
342 {
343 	int	status;
344 
345 	if ((status = mod_remove(&modlinkage)) != 0)
346 		return (status);
347 	vdc_efi_fini();
348 	ddi_soft_state_fini(&vdc_state);
349 	return (0);
350 }
351 
352 static int
353 vdc_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd,  void *arg, void **resultp)
354 {
355 	_NOTE(ARGUNUSED(dip))
356 
357 	int	instance = VDCUNIT((dev_t)arg);
358 	vdc_t	*vdc = NULL;
359 
360 	switch (cmd) {
361 	case DDI_INFO_DEVT2DEVINFO:
362 		if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
363 			*resultp = NULL;
364 			return (DDI_FAILURE);
365 		}
366 		*resultp = vdc->dip;
367 		return (DDI_SUCCESS);
368 	case DDI_INFO_DEVT2INSTANCE:
369 		*resultp = (void *)(uintptr_t)instance;
370 		return (DDI_SUCCESS);
371 	default:
372 		*resultp = NULL;
373 		return (DDI_FAILURE);
374 	}
375 }
376 
377 static int
378 vdc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
379 {
380 	kt_did_t failfast_tid, ownership_tid;
381 	int	instance;
382 	int	rv;
383 	vdc_t	*vdc = NULL;
384 
385 	switch (cmd) {
386 	case DDI_DETACH:
387 		/* the real work happens below */
388 		break;
389 	case DDI_SUSPEND:
390 		/* nothing to do for this non-device */
391 		return (DDI_SUCCESS);
392 	default:
393 		return (DDI_FAILURE);
394 	}
395 
396 	ASSERT(cmd == DDI_DETACH);
397 	instance = ddi_get_instance(dip);
398 	DMSGX(1, "[%d] Entered\n", instance);
399 
400 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
401 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
402 		return (DDI_FAILURE);
403 	}
404 
405 	/*
406 	 * This function is called when vdc is detached or if it has failed to
407 	 * attach. In that case, the attach may have fail before the vdisk type
408 	 * has been set so we can't call vdc_is_opened(). However as the attach
409 	 * has failed, we know that the vdisk is not opened and we can safely
410 	 * detach.
411 	 */
412 	if (vdc->vdisk_type != VD_DISK_TYPE_UNK && vdc_is_opened(vdc)) {
413 		DMSG(vdc, 0, "[%d] Cannot detach: device is open", instance);
414 		return (DDI_FAILURE);
415 	}
416 
417 	if (vdc->dkio_flush_pending) {
418 		DMSG(vdc, 0,
419 		    "[%d] Cannot detach: %d outstanding DKIO flushes\n",
420 		    instance, vdc->dkio_flush_pending);
421 		return (DDI_FAILURE);
422 	}
423 
424 	if (vdc->validate_pending) {
425 		DMSG(vdc, 0,
426 		    "[%d] Cannot detach: %d outstanding validate request\n",
427 		    instance, vdc->validate_pending);
428 		return (DDI_FAILURE);
429 	}
430 
431 	DMSG(vdc, 0, "[%d] proceeding...\n", instance);
432 
433 	/* If we took ownership, release ownership */
434 	mutex_enter(&vdc->ownership_lock);
435 	if (vdc->ownership & VDC_OWNERSHIP_GRANTED) {
436 		rv = vdc_access_set(vdc, VD_ACCESS_SET_CLEAR, FKIOCTL);
437 		if (rv == 0) {
438 			vdc_ownership_update(vdc, VDC_OWNERSHIP_NONE);
439 		}
440 	}
441 	mutex_exit(&vdc->ownership_lock);
442 
443 	/* mark instance as detaching */
444 	vdc->lifecycle	= VDC_LC_DETACHING;
445 
446 	/*
447 	 * try and disable callbacks to prevent another handshake
448 	 */
449 	rv = ldc_set_cb_mode(vdc->ldc_handle, LDC_CB_DISABLE);
450 	DMSG(vdc, 0, "callback disabled (rv=%d)\n", rv);
451 
452 	if (vdc->initialized & VDC_THREAD) {
453 		mutex_enter(&vdc->read_lock);
454 		if ((vdc->read_state == VDC_READ_WAITING) ||
455 		    (vdc->read_state == VDC_READ_RESET)) {
456 			vdc->read_state = VDC_READ_RESET;
457 			cv_signal(&vdc->read_cv);
458 		}
459 
460 		mutex_exit(&vdc->read_lock);
461 
462 		/* wake up any thread waiting for connection to come online */
463 		mutex_enter(&vdc->lock);
464 		if (vdc->state == VDC_STATE_INIT_WAITING) {
465 			DMSG(vdc, 0,
466 			    "[%d] write reset - move to resetting state...\n",
467 			    instance);
468 			vdc->state = VDC_STATE_RESETTING;
469 			cv_signal(&vdc->initwait_cv);
470 		}
471 		mutex_exit(&vdc->lock);
472 
473 		/* now wait until state transitions to VDC_STATE_DETACH */
474 		thread_join(vdc->msg_proc_thr->t_did);
475 		ASSERT(vdc->state == VDC_STATE_DETACH);
476 		DMSG(vdc, 0, "[%d] Reset thread exit and join ..\n",
477 		    vdc->instance);
478 	}
479 
480 	mutex_enter(&vdc->lock);
481 
482 	if (vdc->initialized & VDC_DRING)
483 		vdc_destroy_descriptor_ring(vdc);
484 
485 	if (vdc->initialized & VDC_LDC)
486 		vdc_terminate_ldc(vdc);
487 
488 	if (vdc->failfast_thread) {
489 		failfast_tid = vdc->failfast_thread->t_did;
490 		vdc->failfast_interval = 0;
491 		cv_signal(&vdc->failfast_cv);
492 	} else {
493 		failfast_tid = 0;
494 	}
495 
496 	if (vdc->ownership & VDC_OWNERSHIP_WANTED) {
497 		ownership_tid = vdc->ownership_thread->t_did;
498 		vdc->ownership = VDC_OWNERSHIP_NONE;
499 		cv_signal(&vdc->ownership_cv);
500 	} else {
501 		ownership_tid = 0;
502 	}
503 
504 	mutex_exit(&vdc->lock);
505 
506 	if (failfast_tid != 0)
507 		thread_join(failfast_tid);
508 
509 	if (ownership_tid != 0)
510 		thread_join(ownership_tid);
511 
512 	if (vdc->initialized & VDC_MINOR) {
513 		ddi_prop_remove_all(dip);
514 		ddi_remove_minor_node(dip, NULL);
515 	}
516 
517 	if (vdc->initialized & VDC_LOCKS) {
518 		mutex_destroy(&vdc->lock);
519 		mutex_destroy(&vdc->read_lock);
520 		mutex_destroy(&vdc->ownership_lock);
521 		cv_destroy(&vdc->initwait_cv);
522 		cv_destroy(&vdc->dring_free_cv);
523 		cv_destroy(&vdc->membind_cv);
524 		cv_destroy(&vdc->sync_pending_cv);
525 		cv_destroy(&vdc->sync_blocked_cv);
526 		cv_destroy(&vdc->read_cv);
527 		cv_destroy(&vdc->running_cv);
528 		cv_destroy(&vdc->ownership_cv);
529 		cv_destroy(&vdc->failfast_cv);
530 		cv_destroy(&vdc->failfast_io_cv);
531 	}
532 
533 	if (vdc->minfo)
534 		kmem_free(vdc->minfo, sizeof (struct dk_minfo));
535 
536 	if (vdc->cinfo)
537 		kmem_free(vdc->cinfo, sizeof (struct dk_cinfo));
538 
539 	if (vdc->vtoc)
540 		kmem_free(vdc->vtoc, sizeof (struct vtoc));
541 
542 	if (vdc->geom)
543 		kmem_free(vdc->geom, sizeof (struct dk_geom));
544 
545 	if (vdc->devid) {
546 		ddi_devid_unregister(dip);
547 		ddi_devid_free(vdc->devid);
548 	}
549 
550 	if (vdc->initialized & VDC_SOFT_STATE)
551 		ddi_soft_state_free(vdc_state, instance);
552 
553 	DMSG(vdc, 0, "[%d] End %p\n", instance, (void *)vdc);
554 
555 	return (DDI_SUCCESS);
556 }
557 
558 
559 static int
560 vdc_do_attach(dev_info_t *dip)
561 {
562 	int		instance;
563 	vdc_t		*vdc = NULL;
564 	int		status;
565 	md_t		*mdp;
566 	mde_cookie_t	vd_node, vd_port;
567 
568 	ASSERT(dip != NULL);
569 
570 	instance = ddi_get_instance(dip);
571 	if (ddi_soft_state_zalloc(vdc_state, instance) != DDI_SUCCESS) {
572 		cmn_err(CE_NOTE, "[%d] Couldn't alloc state structure",
573 		    instance);
574 		return (DDI_FAILURE);
575 	}
576 
577 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
578 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
579 		return (DDI_FAILURE);
580 	}
581 
582 	/*
583 	 * We assign the value to initialized in this case to zero out the
584 	 * variable and then set bits in it to indicate what has been done
585 	 */
586 	vdc->initialized = VDC_SOFT_STATE;
587 
588 	vdc_hz_min_ldc_delay = drv_usectohz(vdc_min_timeout_ldc);
589 	vdc_hz_max_ldc_delay = drv_usectohz(vdc_max_timeout_ldc);
590 
591 	vdc->dip	= dip;
592 	vdc->instance	= instance;
593 	vdc->vdisk_type	= VD_DISK_TYPE_UNK;
594 	vdc->vdisk_label = VD_DISK_LABEL_UNK;
595 	vdc->state	= VDC_STATE_INIT;
596 	vdc->lifecycle	= VDC_LC_ATTACHING;
597 	vdc->ldc_state	= 0;
598 	vdc->session_id = 0;
599 	vdc->block_size = DEV_BSIZE;
600 	vdc->max_xfer_sz = maxphys / DEV_BSIZE;
601 
602 	/*
603 	 * We assume, for now, that the vDisk server will export 'read'
604 	 * operations to us at a minimum (this is needed because of checks
605 	 * in vdc for supported operations early in the handshake process).
606 	 * The vDisk server will return ENOTSUP if this is not the case.
607 	 * The value will be overwritten during the attribute exchange with
608 	 * the bitmask of operations exported by server.
609 	 */
610 	vdc->operations = VD_OP_MASK_READ;
611 
612 	vdc->vtoc = NULL;
613 	vdc->geom = NULL;
614 	vdc->cinfo = NULL;
615 	vdc->minfo = NULL;
616 
617 	mutex_init(&vdc->lock, NULL, MUTEX_DRIVER, NULL);
618 	cv_init(&vdc->initwait_cv, NULL, CV_DRIVER, NULL);
619 	cv_init(&vdc->dring_free_cv, NULL, CV_DRIVER, NULL);
620 	cv_init(&vdc->membind_cv, NULL, CV_DRIVER, NULL);
621 	cv_init(&vdc->running_cv, NULL, CV_DRIVER, NULL);
622 
623 	vdc->threads_pending = 0;
624 	vdc->sync_op_pending = B_FALSE;
625 	vdc->sync_op_blocked = B_FALSE;
626 	cv_init(&vdc->sync_pending_cv, NULL, CV_DRIVER, NULL);
627 	cv_init(&vdc->sync_blocked_cv, NULL, CV_DRIVER, NULL);
628 
629 	mutex_init(&vdc->ownership_lock, NULL, MUTEX_DRIVER, NULL);
630 	cv_init(&vdc->ownership_cv, NULL, CV_DRIVER, NULL);
631 	cv_init(&vdc->failfast_cv, NULL, CV_DRIVER, NULL);
632 	cv_init(&vdc->failfast_io_cv, NULL, CV_DRIVER, NULL);
633 
634 	/* init blocking msg read functionality */
635 	mutex_init(&vdc->read_lock, NULL, MUTEX_DRIVER, NULL);
636 	cv_init(&vdc->read_cv, NULL, CV_DRIVER, NULL);
637 	vdc->read_state = VDC_READ_IDLE;
638 
639 	vdc->initialized |= VDC_LOCKS;
640 
641 	/* get device and port MD node for this disk instance */
642 	if (vdc_get_md_node(dip, &mdp, &vd_node, &vd_port) != 0) {
643 		cmn_err(CE_NOTE, "[%d] Could not get machine description node",
644 		    instance);
645 		return (DDI_FAILURE);
646 	}
647 
648 	/* set the connection timeout */
649 	if (vd_port == NULL || (md_get_prop_val(mdp, vd_port,
650 	    VDC_MD_TIMEOUT, &vdc->ctimeout) != 0)) {
651 		vdc->ctimeout = 0;
652 	}
653 
654 	/* initialise LDC channel which will be used to communicate with vds */
655 	status = vdc_do_ldc_init(vdc, mdp, vd_node);
656 
657 	(void) md_fini_handle(mdp);
658 
659 	if (status != 0) {
660 		cmn_err(CE_NOTE, "[%d] Couldn't initialize LDC", instance);
661 		goto return_status;
662 	}
663 
664 	/* initialize the thread responsible for managing state with server */
665 	vdc->msg_proc_thr = thread_create(NULL, 0, vdc_process_msg_thread,
666 	    vdc, 0, &p0, TS_RUN, minclsyspri);
667 	if (vdc->msg_proc_thr == NULL) {
668 		cmn_err(CE_NOTE, "[%d] Failed to create msg processing thread",
669 		    instance);
670 		return (DDI_FAILURE);
671 	}
672 
673 	vdc->initialized |= VDC_THREAD;
674 
675 	atomic_inc_32(&vdc_instance_count);
676 
677 	/*
678 	 * Check the disk label. This will send requests and do the handshake.
679 	 * We don't really care about the disk label now. What we really need is
680 	 * the handshake do be done so that we know the type of the disk (slice
681 	 * or full disk) and the appropriate device nodes can be created.
682 	 */
683 	vdc->vdisk_label = VD_DISK_LABEL_UNK;
684 	vdc->vtoc = kmem_zalloc(sizeof (struct vtoc), KM_SLEEP);
685 	vdc->geom = kmem_zalloc(sizeof (struct dk_geom), KM_SLEEP);
686 	vdc->minfo = kmem_zalloc(sizeof (struct dk_minfo), KM_SLEEP);
687 
688 	mutex_enter(&vdc->lock);
689 	(void) vdc_validate_geometry(vdc);
690 	mutex_exit(&vdc->lock);
691 
692 	/*
693 	 * Now that we have the device info we can create the
694 	 * device nodes and properties
695 	 */
696 	status = vdc_create_device_nodes(vdc);
697 	if (status) {
698 		DMSG(vdc, 0, "[%d] Failed to create device nodes",
699 		    instance);
700 		goto return_status;
701 	}
702 	status = vdc_create_device_nodes_props(vdc);
703 	if (status) {
704 		DMSG(vdc, 0, "[%d] Failed to create device nodes"
705 		    " properties (%d)", instance, status);
706 		goto return_status;
707 	}
708 
709 	/*
710 	 * Setup devid
711 	 */
712 	if (vdc_setup_devid(vdc)) {
713 		DMSG(vdc, 0, "[%d] No device id available\n", instance);
714 	}
715 
716 	ddi_report_dev(dip);
717 	vdc->lifecycle	= VDC_LC_ONLINE;
718 	DMSG(vdc, 0, "[%d] Attach tasks successful\n", instance);
719 
720 return_status:
721 	DMSG(vdc, 0, "[%d] Attach completed\n", instance);
722 	return (status);
723 }
724 
725 static int
726 vdc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
727 {
728 	int	status;
729 
730 	switch (cmd) {
731 	case DDI_ATTACH:
732 		if ((status = vdc_do_attach(dip)) != 0)
733 			(void) vdc_detach(dip, DDI_DETACH);
734 		return (status);
735 	case DDI_RESUME:
736 		/* nothing to do for this non-device */
737 		return (DDI_SUCCESS);
738 	default:
739 		return (DDI_FAILURE);
740 	}
741 }
742 
743 static int
744 vdc_do_ldc_init(vdc_t *vdc, md_t *mdp, mde_cookie_t vd_node)
745 {
746 	int			status = 0;
747 	ldc_status_t		ldc_state;
748 	ldc_attr_t		ldc_attr;
749 	uint64_t		ldc_id = 0;
750 
751 	ASSERT(vdc != NULL);
752 
753 	vdc->initialized |= VDC_LDC;
754 
755 	if ((status = vdc_get_ldc_id(mdp, vd_node, &ldc_id)) != 0) {
756 		DMSG(vdc, 0, "[%d] Failed to get LDC channel ID property",
757 		    vdc->instance);
758 		return (EIO);
759 	}
760 
761 	DMSGX(0, "[%d] LDC id is 0x%lx\n", vdc->instance, ldc_id);
762 
763 	vdc->ldc_id = ldc_id;
764 
765 	ldc_attr.devclass = LDC_DEV_BLK;
766 	ldc_attr.instance = vdc->instance;
767 	ldc_attr.mode = LDC_MODE_UNRELIABLE;	/* unreliable transport */
768 	ldc_attr.mtu = VD_LDC_MTU;
769 
770 	if ((vdc->initialized & VDC_LDC_INIT) == 0) {
771 		status = ldc_init(ldc_id, &ldc_attr, &vdc->ldc_handle);
772 		if (status != 0) {
773 			DMSG(vdc, 0, "[%d] ldc_init(chan %ld) returned %d",
774 			    vdc->instance, ldc_id, status);
775 			return (status);
776 		}
777 		vdc->initialized |= VDC_LDC_INIT;
778 	}
779 	status = ldc_status(vdc->ldc_handle, &ldc_state);
780 	if (status != 0) {
781 		DMSG(vdc, 0, "[%d] Cannot discover LDC status [err=%d]",
782 		    vdc->instance, status);
783 		return (status);
784 	}
785 	vdc->ldc_state = ldc_state;
786 
787 	if ((vdc->initialized & VDC_LDC_CB) == 0) {
788 		status = ldc_reg_callback(vdc->ldc_handle, vdc_handle_cb,
789 		    (caddr_t)vdc);
790 		if (status != 0) {
791 			DMSG(vdc, 0, "[%d] LDC callback reg. failed (%d)",
792 			    vdc->instance, status);
793 			return (status);
794 		}
795 		vdc->initialized |= VDC_LDC_CB;
796 	}
797 
798 	vdc->initialized |= VDC_LDC;
799 
800 	/*
801 	 * At this stage we have initialised LDC, we will now try and open
802 	 * the connection.
803 	 */
804 	if (vdc->ldc_state == LDC_INIT) {
805 		status = ldc_open(vdc->ldc_handle);
806 		if (status != 0) {
807 			DMSG(vdc, 0, "[%d] ldc_open(chan %ld) returned %d",
808 			    vdc->instance, vdc->ldc_id, status);
809 			return (status);
810 		}
811 		vdc->initialized |= VDC_LDC_OPEN;
812 	}
813 
814 	return (status);
815 }
816 
817 static int
818 vdc_start_ldc_connection(vdc_t *vdc)
819 {
820 	int		status = 0;
821 
822 	ASSERT(vdc != NULL);
823 
824 	ASSERT(MUTEX_HELD(&vdc->lock));
825 
826 	status = vdc_do_ldc_up(vdc);
827 
828 	DMSG(vdc, 0, "[%d] Finished bringing up LDC\n", vdc->instance);
829 
830 	return (status);
831 }
832 
833 static int
834 vdc_stop_ldc_connection(vdc_t *vdcp)
835 {
836 	int	status;
837 
838 	DMSG(vdcp, 0, ": Resetting connection to vDisk server : state %d\n",
839 	    vdcp->state);
840 
841 	status = ldc_down(vdcp->ldc_handle);
842 	DMSG(vdcp, 0, "ldc_down() = %d\n", status);
843 
844 	vdcp->initialized &= ~VDC_HANDSHAKE;
845 	DMSG(vdcp, 0, "initialized=%x\n", vdcp->initialized);
846 
847 	return (status);
848 }
849 
850 static int
851 vdc_create_device_nodes_efi(vdc_t *vdc)
852 {
853 	ddi_remove_minor_node(vdc->dip, "h");
854 	ddi_remove_minor_node(vdc->dip, "h,raw");
855 
856 	if (ddi_create_minor_node(vdc->dip, "wd", S_IFBLK,
857 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
858 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
859 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'wd'",
860 		    vdc->instance);
861 		return (EIO);
862 	}
863 
864 	/* if any device node is created we set this flag */
865 	vdc->initialized |= VDC_MINOR;
866 
867 	if (ddi_create_minor_node(vdc->dip, "wd,raw", S_IFCHR,
868 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
869 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
870 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'wd,raw'",
871 		    vdc->instance);
872 		return (EIO);
873 	}
874 
875 	return (0);
876 }
877 
878 static int
879 vdc_create_device_nodes_vtoc(vdc_t *vdc)
880 {
881 	ddi_remove_minor_node(vdc->dip, "wd");
882 	ddi_remove_minor_node(vdc->dip, "wd,raw");
883 
884 	if (ddi_create_minor_node(vdc->dip, "h", S_IFBLK,
885 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
886 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
887 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'h'",
888 		    vdc->instance);
889 		return (EIO);
890 	}
891 
892 	/* if any device node is created we set this flag */
893 	vdc->initialized |= VDC_MINOR;
894 
895 	if (ddi_create_minor_node(vdc->dip, "h,raw", S_IFCHR,
896 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
897 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
898 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'h,raw'",
899 		    vdc->instance);
900 		return (EIO);
901 	}
902 
903 	return (0);
904 }
905 
906 /*
907  * Function:
908  *	vdc_create_device_nodes
909  *
910  * Description:
911  *	This function creates the block and character device nodes under
912  *	/devices along with the node properties. It is called as part of
913  *	the attach(9E) of the instance during the handshake with vds after
914  *	vds has sent the attributes to vdc.
915  *
916  *	If the device is of type VD_DISK_TYPE_SLICE then the minor node
917  *	of 2 is used in keeping with the Solaris convention that slice 2
918  *	refers to a whole disk. Slices start at 'a'
919  *
920  * Parameters:
921  *	vdc 		- soft state pointer
922  *
923  * Return Values
924  *	0		- Success
925  *	EIO		- Failed to create node
926  *	EINVAL		- Unknown type of disk exported
927  */
928 static int
929 vdc_create_device_nodes(vdc_t *vdc)
930 {
931 	char		name[sizeof ("s,raw")];
932 	dev_info_t	*dip = NULL;
933 	int		instance, status;
934 	int		num_slices = 1;
935 	int		i;
936 
937 	ASSERT(vdc != NULL);
938 
939 	instance = vdc->instance;
940 	dip = vdc->dip;
941 
942 	switch (vdc->vdisk_type) {
943 	case VD_DISK_TYPE_DISK:
944 		num_slices = V_NUMPAR;
945 		break;
946 	case VD_DISK_TYPE_SLICE:
947 		num_slices = 1;
948 		break;
949 	case VD_DISK_TYPE_UNK:
950 	default:
951 		return (EINVAL);
952 	}
953 
954 	/*
955 	 * Minor nodes are different for EFI disks: EFI disks do not have
956 	 * a minor node 'g' for the minor number corresponding to slice
957 	 * VD_EFI_WD_SLICE (slice 7) instead they have a minor node 'wd'
958 	 * representing the whole disk.
959 	 */
960 	for (i = 0; i < num_slices; i++) {
961 
962 		if (i == VD_EFI_WD_SLICE) {
963 			if (vdc->vdisk_label == VD_DISK_LABEL_EFI)
964 				status = vdc_create_device_nodes_efi(vdc);
965 			else
966 				status = vdc_create_device_nodes_vtoc(vdc);
967 			if (status != 0)
968 				return (status);
969 			continue;
970 		}
971 
972 		(void) snprintf(name, sizeof (name), "%c", 'a' + i);
973 		if (ddi_create_minor_node(dip, name, S_IFBLK,
974 		    VD_MAKE_DEV(instance, i), DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
975 			cmn_err(CE_NOTE, "[%d] Couldn't add block node '%s'",
976 			    instance, name);
977 			return (EIO);
978 		}
979 
980 		/* if any device node is created we set this flag */
981 		vdc->initialized |= VDC_MINOR;
982 
983 		(void) snprintf(name, sizeof (name), "%c%s", 'a' + i, ",raw");
984 
985 		if (ddi_create_minor_node(dip, name, S_IFCHR,
986 		    VD_MAKE_DEV(instance, i), DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
987 			cmn_err(CE_NOTE, "[%d] Couldn't add raw node '%s'",
988 			    instance, name);
989 			return (EIO);
990 		}
991 	}
992 
993 	return (0);
994 }
995 
996 /*
997  * Function:
998  *	vdc_create_device_nodes_props
999  *
1000  * Description:
1001  *	This function creates the block and character device nodes under
1002  *	/devices along with the node properties. It is called as part of
1003  *	the attach(9E) of the instance during the handshake with vds after
1004  *	vds has sent the attributes to vdc.
1005  *
1006  * Parameters:
1007  *	vdc 		- soft state pointer
1008  *
1009  * Return Values
1010  *	0		- Success
1011  *	EIO		- Failed to create device node property
1012  *	EINVAL		- Unknown type of disk exported
1013  */
1014 static int
1015 vdc_create_device_nodes_props(vdc_t *vdc)
1016 {
1017 	dev_info_t	*dip = NULL;
1018 	int		instance;
1019 	int		num_slices = 1;
1020 	int64_t		size = 0;
1021 	dev_t		dev;
1022 	int		rv;
1023 	int		i;
1024 
1025 	ASSERT(vdc != NULL);
1026 	ASSERT(vdc->vtoc != NULL);
1027 
1028 	instance = vdc->instance;
1029 	dip = vdc->dip;
1030 
1031 	switch (vdc->vdisk_type) {
1032 	case VD_DISK_TYPE_DISK:
1033 		num_slices = V_NUMPAR;
1034 		break;
1035 	case VD_DISK_TYPE_SLICE:
1036 		num_slices = 1;
1037 		break;
1038 	case VD_DISK_TYPE_UNK:
1039 	default:
1040 		return (EINVAL);
1041 	}
1042 
1043 	if (vdc->vdisk_label == VD_DISK_LABEL_UNK) {
1044 		/* remove all properties */
1045 		for (i = 0; i < num_slices; i++) {
1046 			dev = makedevice(ddi_driver_major(dip),
1047 			    VD_MAKE_DEV(instance, i));
1048 			(void) ddi_prop_remove(dev, dip, VDC_SIZE_PROP_NAME);
1049 			(void) ddi_prop_remove(dev, dip, VDC_NBLOCKS_PROP_NAME);
1050 		}
1051 		return (0);
1052 	}
1053 
1054 	for (i = 0; i < num_slices; i++) {
1055 		dev = makedevice(ddi_driver_major(dip),
1056 		    VD_MAKE_DEV(instance, i));
1057 
1058 		size = vdc->vtoc->v_part[i].p_size * vdc->vtoc->v_sectorsz;
1059 		DMSG(vdc, 0, "[%d] sz %ld (%ld Mb)  p_size %lx\n",
1060 		    instance, size, size / (1024 * 1024),
1061 		    vdc->vtoc->v_part[i].p_size);
1062 
1063 		rv = ddi_prop_update_int64(dev, dip, VDC_SIZE_PROP_NAME, size);
1064 		if (rv != DDI_PROP_SUCCESS) {
1065 			cmn_err(CE_NOTE, "[%d] Couldn't add '%s' prop of [%ld]",
1066 			    instance, VDC_SIZE_PROP_NAME, size);
1067 			return (EIO);
1068 		}
1069 
1070 		rv = ddi_prop_update_int64(dev, dip, VDC_NBLOCKS_PROP_NAME,
1071 		    lbtodb(size));
1072 		if (rv != DDI_PROP_SUCCESS) {
1073 			cmn_err(CE_NOTE, "[%d] Couldn't add '%s' prop [%llu]",
1074 			    instance, VDC_NBLOCKS_PROP_NAME, lbtodb(size));
1075 			return (EIO);
1076 		}
1077 	}
1078 
1079 	return (0);
1080 }
1081 
1082 /*
1083  * Function:
1084  *	vdc_is_opened
1085  *
1086  * Description:
1087  *	This function checks if any slice of a given virtual disk is
1088  *	currently opened.
1089  *
1090  * Parameters:
1091  *	vdc 		- soft state pointer
1092  *
1093  * Return Values
1094  *	B_TRUE		- at least one slice is opened.
1095  *	B_FALSE		- no slice is opened.
1096  */
1097 static boolean_t
1098 vdc_is_opened(vdc_t *vdc)
1099 {
1100 	int i, nslices;
1101 
1102 	switch (vdc->vdisk_type) {
1103 	case VD_DISK_TYPE_DISK:
1104 		nslices = V_NUMPAR;
1105 		break;
1106 	case VD_DISK_TYPE_SLICE:
1107 		nslices = 1;
1108 		break;
1109 	case VD_DISK_TYPE_UNK:
1110 	default:
1111 		ASSERT(0);
1112 	}
1113 
1114 	/* check if there's any layered open */
1115 	for (i = 0; i < nslices; i++) {
1116 		if (vdc->open_lyr[i] > 0)
1117 			return (B_TRUE);
1118 	}
1119 
1120 	/* check if there is any other kind of open */
1121 	for (i = 0; i < OTYPCNT; i++) {
1122 		if (vdc->open[i] != 0)
1123 			return (B_TRUE);
1124 	}
1125 
1126 	return (B_FALSE);
1127 }
1128 
1129 static int
1130 vdc_mark_opened(vdc_t *vdc, int slice, int flag, int otyp)
1131 {
1132 	uint8_t slicemask;
1133 	int i;
1134 
1135 	ASSERT(otyp < OTYPCNT);
1136 	ASSERT(slice < V_NUMPAR);
1137 	ASSERT(MUTEX_HELD(&vdc->lock));
1138 
1139 	slicemask = 1 << slice;
1140 
1141 	/* check if slice is already exclusively opened */
1142 	if (vdc->open_excl & slicemask)
1143 		return (EBUSY);
1144 
1145 	/* if open exclusive, check if slice is already opened */
1146 	if (flag & FEXCL) {
1147 		if (vdc->open_lyr[slice] > 0)
1148 			return (EBUSY);
1149 		for (i = 0; i < OTYPCNT; i++) {
1150 			if (vdc->open[i] & slicemask)
1151 				return (EBUSY);
1152 		}
1153 		vdc->open_excl |= slicemask;
1154 	}
1155 
1156 	/* mark slice as opened */
1157 	if (otyp == OTYP_LYR) {
1158 		vdc->open_lyr[slice]++;
1159 	} else {
1160 		vdc->open[otyp] |= slicemask;
1161 	}
1162 
1163 	return (0);
1164 }
1165 
1166 static void
1167 vdc_mark_closed(vdc_t *vdc, int slice, int flag, int otyp)
1168 {
1169 	uint8_t slicemask;
1170 
1171 	ASSERT(otyp < OTYPCNT);
1172 	ASSERT(slice < V_NUMPAR);
1173 	ASSERT(MUTEX_HELD(&vdc->lock));
1174 
1175 	slicemask = 1 << slice;
1176 
1177 	if (otyp == OTYP_LYR) {
1178 		ASSERT(vdc->open_lyr[slice] > 0);
1179 		vdc->open_lyr[slice]--;
1180 	} else {
1181 		vdc->open[otyp] &= ~slicemask;
1182 	}
1183 
1184 	if (flag & FEXCL)
1185 		vdc->open_excl &= ~slicemask;
1186 }
1187 
1188 static int
1189 vdc_open(dev_t *dev, int flag, int otyp, cred_t *cred)
1190 {
1191 	_NOTE(ARGUNUSED(cred))
1192 
1193 	int	instance;
1194 	int	slice, status = 0;
1195 	vdc_t	*vdc;
1196 
1197 	ASSERT(dev != NULL);
1198 	instance = VDCUNIT(*dev);
1199 
1200 	if (otyp >= OTYPCNT)
1201 		return (EINVAL);
1202 
1203 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1204 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1205 		return (ENXIO);
1206 	}
1207 
1208 	DMSG(vdc, 0, "minor = %d flag = %x, otyp = %x\n",
1209 	    getminor(*dev), flag, otyp);
1210 
1211 	slice = VDCPART(*dev);
1212 
1213 	mutex_enter(&vdc->lock);
1214 
1215 	status = vdc_mark_opened(vdc, slice, flag, otyp);
1216 
1217 	if (status != 0) {
1218 		mutex_exit(&vdc->lock);
1219 		return (status);
1220 	}
1221 
1222 	if (flag & (FNDELAY | FNONBLOCK)) {
1223 
1224 		/* don't resubmit a validate request if there's already one */
1225 		if (vdc->validate_pending > 0) {
1226 			mutex_exit(&vdc->lock);
1227 			return (0);
1228 		}
1229 
1230 		/* call vdc_validate() asynchronously to avoid blocking */
1231 		if (taskq_dispatch(system_taskq, vdc_validate_task,
1232 		    (void *)vdc, TQ_NOSLEEP) == NULL) {
1233 			vdc_mark_closed(vdc, slice, flag, otyp);
1234 			mutex_exit(&vdc->lock);
1235 			return (ENXIO);
1236 		}
1237 
1238 		vdc->validate_pending++;
1239 		mutex_exit(&vdc->lock);
1240 		return (0);
1241 	}
1242 
1243 	mutex_exit(&vdc->lock);
1244 
1245 	vdc_validate(vdc);
1246 
1247 	mutex_enter(&vdc->lock);
1248 
1249 	if (vdc->vdisk_label == VD_DISK_LABEL_UNK ||
1250 	    vdc->vtoc->v_part[slice].p_size == 0) {
1251 		vdc_mark_closed(vdc, slice, flag, otyp);
1252 		status = EIO;
1253 	}
1254 
1255 	mutex_exit(&vdc->lock);
1256 
1257 	return (status);
1258 }
1259 
1260 static int
1261 vdc_close(dev_t dev, int flag, int otyp, cred_t *cred)
1262 {
1263 	_NOTE(ARGUNUSED(cred))
1264 
1265 	int	instance;
1266 	int	slice;
1267 	int	rv, rval;
1268 	vdc_t	*vdc;
1269 
1270 	instance = VDCUNIT(dev);
1271 
1272 	if (otyp >= OTYPCNT)
1273 		return (EINVAL);
1274 
1275 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1276 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1277 		return (ENXIO);
1278 	}
1279 
1280 	DMSG(vdc, 0, "[%d] flag = %x, otyp = %x\n", instance, flag, otyp);
1281 
1282 	slice = VDCPART(dev);
1283 
1284 	/*
1285 	 * Attempt to flush the W$ on a close operation. If this is
1286 	 * not a supported IOCTL command or the backing device is read-only
1287 	 * do not fail the close operation.
1288 	 */
1289 	rv = vd_process_ioctl(dev, DKIOCFLUSHWRITECACHE, NULL, FKIOCTL, &rval);
1290 
1291 	if (rv != 0 && rv != ENOTSUP && rv != ENOTTY && rv != EROFS) {
1292 		DMSG(vdc, 0, "[%d] flush failed with error %d on close\n",
1293 		    instance, rv);
1294 		return (EIO);
1295 	}
1296 
1297 	mutex_enter(&vdc->lock);
1298 	vdc_mark_closed(vdc, slice, flag, otyp);
1299 	mutex_exit(&vdc->lock);
1300 
1301 	return (0);
1302 }
1303 
1304 static int
1305 vdc_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *credp, int *rvalp)
1306 {
1307 	_NOTE(ARGUNUSED(credp))
1308 
1309 	return (vd_process_ioctl(dev, cmd, (caddr_t)arg, mode, rvalp));
1310 }
1311 
1312 static int
1313 vdc_print(dev_t dev, char *str)
1314 {
1315 	cmn_err(CE_NOTE, "vdc%d:  %s", VDCUNIT(dev), str);
1316 	return (0);
1317 }
1318 
1319 static int
1320 vdc_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk)
1321 {
1322 	int	rv;
1323 	size_t	nbytes = nblk * DEV_BSIZE;
1324 	int	instance = VDCUNIT(dev);
1325 	vdc_t	*vdc = NULL;
1326 
1327 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1328 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1329 		return (ENXIO);
1330 	}
1331 
1332 	DMSG(vdc, 2, "[%d] dump %ld bytes at block 0x%lx : addr=0x%p\n",
1333 	    instance, nbytes, blkno, (void *)addr);
1334 	rv = vdc_send_request(vdc, VD_OP_BWRITE, addr, nbytes,
1335 	    VDCPART(dev), blkno, CB_STRATEGY, 0, VIO_write_dir);
1336 	if (rv) {
1337 		DMSG(vdc, 0, "Failed to do a disk dump (err=%d)\n", rv);
1338 		return (rv);
1339 	}
1340 
1341 	if (ddi_in_panic())
1342 		(void) vdc_drain_response(vdc);
1343 
1344 	DMSG(vdc, 0, "[%d] End\n", instance);
1345 
1346 	return (0);
1347 }
1348 
1349 /* -------------------------------------------------------------------------- */
1350 
1351 /*
1352  * Disk access routines
1353  *
1354  */
1355 
1356 /*
1357  * vdc_strategy()
1358  *
1359  * Return Value:
1360  *	0:	As per strategy(9E), the strategy() function must return 0
1361  *		[ bioerror(9f) sets b_flags to the proper error code ]
1362  */
1363 static int
1364 vdc_strategy(struct buf *buf)
1365 {
1366 	int	rv = -1;
1367 	vdc_t	*vdc = NULL;
1368 	int	instance = VDCUNIT(buf->b_edev);
1369 	int	op = (buf->b_flags & B_READ) ? VD_OP_BREAD : VD_OP_BWRITE;
1370 	int	slice;
1371 
1372 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1373 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1374 		bioerror(buf, ENXIO);
1375 		biodone(buf);
1376 		return (0);
1377 	}
1378 
1379 	DMSG(vdc, 2, "[%d] %s %ld bytes at block %llx : b_addr=0x%p\n",
1380 	    instance, (buf->b_flags & B_READ) ? "Read" : "Write",
1381 	    buf->b_bcount, buf->b_lblkno, (void *)buf->b_un.b_addr);
1382 	DTRACE_IO2(vstart, buf_t *, buf, vdc_t *, vdc);
1383 
1384 	bp_mapin(buf);
1385 
1386 	if ((long)buf->b_private == VD_SLICE_NONE) {
1387 		/* I/O using an absolute disk offset */
1388 		slice = VD_SLICE_NONE;
1389 	} else {
1390 		slice = VDCPART(buf->b_edev);
1391 	}
1392 
1393 	rv = vdc_send_request(vdc, op, (caddr_t)buf->b_un.b_addr,
1394 	    buf->b_bcount, slice, buf->b_lblkno,
1395 	    CB_STRATEGY, buf, (op == VD_OP_BREAD) ? VIO_read_dir :
1396 	    VIO_write_dir);
1397 
1398 	/*
1399 	 * If the request was successfully sent, the strategy call returns and
1400 	 * the ACK handler calls the bioxxx functions when the vDisk server is
1401 	 * done.
1402 	 */
1403 	if (rv) {
1404 		DMSG(vdc, 0, "Failed to read/write (err=%d)\n", rv);
1405 		bioerror(buf, rv);
1406 		biodone(buf);
1407 	}
1408 
1409 	return (0);
1410 }
1411 
1412 /*
1413  * Function:
1414  *	vdc_min
1415  *
1416  * Description:
1417  *	Routine to limit the size of a data transfer. Used in
1418  *	conjunction with physio(9F).
1419  *
1420  * Arguments:
1421  *	bp - pointer to the indicated buf(9S) struct.
1422  *
1423  */
1424 static void
1425 vdc_min(struct buf *bufp)
1426 {
1427 	vdc_t	*vdc = NULL;
1428 	int	instance = VDCUNIT(bufp->b_edev);
1429 
1430 	vdc = ddi_get_soft_state(vdc_state, instance);
1431 	VERIFY(vdc != NULL);
1432 
1433 	if (bufp->b_bcount > (vdc->max_xfer_sz * vdc->block_size)) {
1434 		bufp->b_bcount = vdc->max_xfer_sz * vdc->block_size;
1435 	}
1436 }
1437 
1438 static int
1439 vdc_read(dev_t dev, struct uio *uio, cred_t *cred)
1440 {
1441 	_NOTE(ARGUNUSED(cred))
1442 
1443 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1444 	return (physio(vdc_strategy, NULL, dev, B_READ, vdc_min, uio));
1445 }
1446 
1447 static int
1448 vdc_write(dev_t dev, struct uio *uio, cred_t *cred)
1449 {
1450 	_NOTE(ARGUNUSED(cred))
1451 
1452 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1453 	return (physio(vdc_strategy, NULL, dev, B_WRITE, vdc_min, uio));
1454 }
1455 
1456 static int
1457 vdc_aread(dev_t dev, struct aio_req *aio, cred_t *cred)
1458 {
1459 	_NOTE(ARGUNUSED(cred))
1460 
1461 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1462 	return (aphysio(vdc_strategy, anocancel, dev, B_READ, vdc_min, aio));
1463 }
1464 
1465 static int
1466 vdc_awrite(dev_t dev, struct aio_req *aio, cred_t *cred)
1467 {
1468 	_NOTE(ARGUNUSED(cred))
1469 
1470 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1471 	return (aphysio(vdc_strategy, anocancel, dev, B_WRITE, vdc_min, aio));
1472 }
1473 
1474 
1475 /* -------------------------------------------------------------------------- */
1476 
1477 /*
1478  * Handshake support
1479  */
1480 
1481 
1482 /*
1483  * Function:
1484  *	vdc_init_ver_negotiation()
1485  *
1486  * Description:
1487  *
1488  * Arguments:
1489  *	vdc	- soft state pointer for this instance of the device driver.
1490  *
1491  * Return Code:
1492  *	0	- Success
1493  */
1494 static int
1495 vdc_init_ver_negotiation(vdc_t *vdc, vio_ver_t ver)
1496 {
1497 	vio_ver_msg_t	pkt;
1498 	size_t		msglen = sizeof (pkt);
1499 	int		status = -1;
1500 
1501 	ASSERT(vdc != NULL);
1502 	ASSERT(mutex_owned(&vdc->lock));
1503 
1504 	DMSG(vdc, 0, "[%d] Entered.\n", vdc->instance);
1505 
1506 	/*
1507 	 * set the Session ID to a unique value
1508 	 * (the lower 32 bits of the clock tick)
1509 	 */
1510 	vdc->session_id = ((uint32_t)gettick() & 0xffffffff);
1511 	DMSG(vdc, 0, "[%d] Set SID to 0x%lx\n", vdc->instance, vdc->session_id);
1512 
1513 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1514 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1515 	pkt.tag.vio_subtype_env = VIO_VER_INFO;
1516 	pkt.tag.vio_sid = vdc->session_id;
1517 	pkt.dev_class = VDEV_DISK;
1518 	pkt.ver_major = ver.major;
1519 	pkt.ver_minor = ver.minor;
1520 
1521 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1522 	DMSG(vdc, 0, "[%d] Ver info sent (status = %d)\n",
1523 	    vdc->instance, status);
1524 	if ((status != 0) || (msglen != sizeof (vio_ver_msg_t))) {
1525 		DMSG(vdc, 0, "[%d] Failed to send Ver negotiation info: "
1526 		    "id(%lx) rv(%d) size(%ld)", vdc->instance, vdc->ldc_handle,
1527 		    status, msglen);
1528 		if (msglen != sizeof (vio_ver_msg_t))
1529 			status = ENOMSG;
1530 	}
1531 
1532 	return (status);
1533 }
1534 
1535 /*
1536  * Function:
1537  *	vdc_ver_negotiation()
1538  *
1539  * Description:
1540  *
1541  * Arguments:
1542  *	vdcp	- soft state pointer for this instance of the device driver.
1543  *
1544  * Return Code:
1545  *	0	- Success
1546  */
1547 static int
1548 vdc_ver_negotiation(vdc_t *vdcp)
1549 {
1550 	vio_msg_t vio_msg;
1551 	int status;
1552 
1553 	if (status = vdc_init_ver_negotiation(vdcp, vdc_version[0]))
1554 		return (status);
1555 
1556 	/* release lock and wait for response */
1557 	mutex_exit(&vdcp->lock);
1558 	status = vdc_wait_for_response(vdcp, &vio_msg);
1559 	mutex_enter(&vdcp->lock);
1560 	if (status) {
1561 		DMSG(vdcp, 0,
1562 		    "[%d] Failed waiting for Ver negotiation response, rv(%d)",
1563 		    vdcp->instance, status);
1564 		return (status);
1565 	}
1566 
1567 	/* check type and sub_type ... */
1568 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1569 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1570 		DMSG(vdcp, 0, "[%d] Invalid ver negotiation response\n",
1571 		    vdcp->instance);
1572 		return (EPROTO);
1573 	}
1574 
1575 	return (vdc_handle_ver_msg(vdcp, (vio_ver_msg_t *)&vio_msg));
1576 }
1577 
1578 /*
1579  * Function:
1580  *	vdc_init_attr_negotiation()
1581  *
1582  * Description:
1583  *
1584  * Arguments:
1585  *	vdc	- soft state pointer for this instance of the device driver.
1586  *
1587  * Return Code:
1588  *	0	- Success
1589  */
1590 static int
1591 vdc_init_attr_negotiation(vdc_t *vdc)
1592 {
1593 	vd_attr_msg_t	pkt;
1594 	size_t		msglen = sizeof (pkt);
1595 	int		status;
1596 
1597 	ASSERT(vdc != NULL);
1598 	ASSERT(mutex_owned(&vdc->lock));
1599 
1600 	DMSG(vdc, 0, "[%d] entered\n", vdc->instance);
1601 
1602 	/* fill in tag */
1603 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1604 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1605 	pkt.tag.vio_subtype_env = VIO_ATTR_INFO;
1606 	pkt.tag.vio_sid = vdc->session_id;
1607 	/* fill in payload */
1608 	pkt.max_xfer_sz = vdc->max_xfer_sz;
1609 	pkt.vdisk_block_size = vdc->block_size;
1610 	pkt.xfer_mode = VIO_DRING_MODE;
1611 	pkt.operations = 0;	/* server will set bits of valid operations */
1612 	pkt.vdisk_type = 0;	/* server will set to valid device type */
1613 	pkt.vdisk_media = 0;	/* server will set to valid media type */
1614 	pkt.vdisk_size = 0;	/* server will set to valid size */
1615 
1616 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1617 	DMSG(vdc, 0, "Attr info sent (status = %d)\n", status);
1618 
1619 	if ((status != 0) || (msglen != sizeof (vio_ver_msg_t))) {
1620 		DMSG(vdc, 0, "[%d] Failed to send Attr negotiation info: "
1621 		    "id(%lx) rv(%d) size(%ld)", vdc->instance, vdc->ldc_handle,
1622 		    status, msglen);
1623 		if (msglen != sizeof (vio_ver_msg_t))
1624 			status = ENOMSG;
1625 	}
1626 
1627 	return (status);
1628 }
1629 
1630 /*
1631  * Function:
1632  *	vdc_attr_negotiation()
1633  *
1634  * Description:
1635  *
1636  * Arguments:
1637  *	vdc	- soft state pointer for this instance of the device driver.
1638  *
1639  * Return Code:
1640  *	0	- Success
1641  */
1642 static int
1643 vdc_attr_negotiation(vdc_t *vdcp)
1644 {
1645 	int status;
1646 	vio_msg_t vio_msg;
1647 
1648 	if (status = vdc_init_attr_negotiation(vdcp))
1649 		return (status);
1650 
1651 	/* release lock and wait for response */
1652 	mutex_exit(&vdcp->lock);
1653 	status = vdc_wait_for_response(vdcp, &vio_msg);
1654 	mutex_enter(&vdcp->lock);
1655 	if (status) {
1656 		DMSG(vdcp, 0,
1657 		    "[%d] Failed waiting for Attr negotiation response, rv(%d)",
1658 		    vdcp->instance, status);
1659 		return (status);
1660 	}
1661 
1662 	/* check type and sub_type ... */
1663 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1664 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1665 		DMSG(vdcp, 0, "[%d] Invalid attr negotiation response\n",
1666 		    vdcp->instance);
1667 		return (EPROTO);
1668 	}
1669 
1670 	return (vdc_handle_attr_msg(vdcp, (vd_attr_msg_t *)&vio_msg));
1671 }
1672 
1673 
1674 /*
1675  * Function:
1676  *	vdc_init_dring_negotiate()
1677  *
1678  * Description:
1679  *
1680  * Arguments:
1681  *	vdc	- soft state pointer for this instance of the device driver.
1682  *
1683  * Return Code:
1684  *	0	- Success
1685  */
1686 static int
1687 vdc_init_dring_negotiate(vdc_t *vdc)
1688 {
1689 	vio_dring_reg_msg_t	pkt;
1690 	size_t			msglen = sizeof (pkt);
1691 	int			status = -1;
1692 	int			retry;
1693 	int			nretries = 10;
1694 
1695 	ASSERT(vdc != NULL);
1696 	ASSERT(mutex_owned(&vdc->lock));
1697 
1698 	for (retry = 0; retry < nretries; retry++) {
1699 		status = vdc_init_descriptor_ring(vdc);
1700 		if (status != EAGAIN)
1701 			break;
1702 		drv_usecwait(vdc_min_timeout_ldc);
1703 	}
1704 
1705 	if (status != 0) {
1706 		DMSG(vdc, 0, "[%d] Failed to init DRing (status = %d)\n",
1707 		    vdc->instance, status);
1708 		return (status);
1709 	}
1710 
1711 	DMSG(vdc, 0, "[%d] Init of descriptor ring completed (status = %d)\n",
1712 	    vdc->instance, status);
1713 
1714 	/* fill in tag */
1715 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1716 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1717 	pkt.tag.vio_subtype_env = VIO_DRING_REG;
1718 	pkt.tag.vio_sid = vdc->session_id;
1719 	/* fill in payload */
1720 	pkt.dring_ident = 0;
1721 	pkt.num_descriptors = vdc->dring_len;
1722 	pkt.descriptor_size = vdc->dring_entry_size;
1723 	pkt.options = (VIO_TX_DRING | VIO_RX_DRING);
1724 	pkt.ncookies = vdc->dring_cookie_count;
1725 	pkt.cookie[0] = vdc->dring_cookie[0];	/* for now just one cookie */
1726 
1727 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1728 	if (status != 0) {
1729 		DMSG(vdc, 0, "[%d] Failed to register DRing (err = %d)",
1730 		    vdc->instance, status);
1731 	}
1732 
1733 	return (status);
1734 }
1735 
1736 
1737 /*
1738  * Function:
1739  *	vdc_dring_negotiation()
1740  *
1741  * Description:
1742  *
1743  * Arguments:
1744  *	vdc	- soft state pointer for this instance of the device driver.
1745  *
1746  * Return Code:
1747  *	0	- Success
1748  */
1749 static int
1750 vdc_dring_negotiation(vdc_t *vdcp)
1751 {
1752 	int status;
1753 	vio_msg_t vio_msg;
1754 
1755 	if (status = vdc_init_dring_negotiate(vdcp))
1756 		return (status);
1757 
1758 	/* release lock and wait for response */
1759 	mutex_exit(&vdcp->lock);
1760 	status = vdc_wait_for_response(vdcp, &vio_msg);
1761 	mutex_enter(&vdcp->lock);
1762 	if (status) {
1763 		DMSG(vdcp, 0,
1764 		    "[%d] Failed waiting for Dring negotiation response,"
1765 		    " rv(%d)", vdcp->instance, status);
1766 		return (status);
1767 	}
1768 
1769 	/* check type and sub_type ... */
1770 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1771 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1772 		DMSG(vdcp, 0, "[%d] Invalid Dring negotiation response\n",
1773 		    vdcp->instance);
1774 		return (EPROTO);
1775 	}
1776 
1777 	return (vdc_handle_dring_reg_msg(vdcp,
1778 	    (vio_dring_reg_msg_t *)&vio_msg));
1779 }
1780 
1781 
1782 /*
1783  * Function:
1784  *	vdc_send_rdx()
1785  *
1786  * Description:
1787  *
1788  * Arguments:
1789  *	vdc	- soft state pointer for this instance of the device driver.
1790  *
1791  * Return Code:
1792  *	0	- Success
1793  */
1794 static int
1795 vdc_send_rdx(vdc_t *vdcp)
1796 {
1797 	vio_msg_t	msg;
1798 	size_t		msglen = sizeof (vio_msg_t);
1799 	int		status;
1800 
1801 	/*
1802 	 * Send an RDX message to vds to indicate we are ready
1803 	 * to send data
1804 	 */
1805 	msg.tag.vio_msgtype = VIO_TYPE_CTRL;
1806 	msg.tag.vio_subtype = VIO_SUBTYPE_INFO;
1807 	msg.tag.vio_subtype_env = VIO_RDX;
1808 	msg.tag.vio_sid = vdcp->session_id;
1809 	status = vdc_send(vdcp, (caddr_t)&msg, &msglen);
1810 	if (status != 0) {
1811 		DMSG(vdcp, 0, "[%d] Failed to send RDX message (%d)",
1812 		    vdcp->instance, status);
1813 	}
1814 
1815 	return (status);
1816 }
1817 
1818 /*
1819  * Function:
1820  *	vdc_handle_rdx()
1821  *
1822  * Description:
1823  *
1824  * Arguments:
1825  *	vdc	- soft state pointer for this instance of the device driver.
1826  *	msgp	- received msg
1827  *
1828  * Return Code:
1829  *	0	- Success
1830  */
1831 static int
1832 vdc_handle_rdx(vdc_t *vdcp, vio_rdx_msg_t *msgp)
1833 {
1834 	_NOTE(ARGUNUSED(vdcp))
1835 	_NOTE(ARGUNUSED(msgp))
1836 
1837 	ASSERT(msgp->tag.vio_msgtype == VIO_TYPE_CTRL);
1838 	ASSERT(msgp->tag.vio_subtype == VIO_SUBTYPE_ACK);
1839 	ASSERT(msgp->tag.vio_subtype_env == VIO_RDX);
1840 
1841 	DMSG(vdcp, 1, "[%d] Got an RDX msg", vdcp->instance);
1842 
1843 	return (0);
1844 }
1845 
1846 /*
1847  * Function:
1848  *	vdc_rdx_exchange()
1849  *
1850  * Description:
1851  *
1852  * Arguments:
1853  *	vdc	- soft state pointer for this instance of the device driver.
1854  *
1855  * Return Code:
1856  *	0	- Success
1857  */
1858 static int
1859 vdc_rdx_exchange(vdc_t *vdcp)
1860 {
1861 	int status;
1862 	vio_msg_t vio_msg;
1863 
1864 	if (status = vdc_send_rdx(vdcp))
1865 		return (status);
1866 
1867 	/* release lock and wait for response */
1868 	mutex_exit(&vdcp->lock);
1869 	status = vdc_wait_for_response(vdcp, &vio_msg);
1870 	mutex_enter(&vdcp->lock);
1871 	if (status) {
1872 		DMSG(vdcp, 0, "[%d] Failed waiting for RDX response, rv(%d)",
1873 		    vdcp->instance, status);
1874 		return (status);
1875 	}
1876 
1877 	/* check type and sub_type ... */
1878 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1879 	    vio_msg.tag.vio_subtype != VIO_SUBTYPE_ACK) {
1880 		DMSG(vdcp, 0, "[%d] Invalid RDX response\n", vdcp->instance);
1881 		return (EPROTO);
1882 	}
1883 
1884 	return (vdc_handle_rdx(vdcp, (vio_rdx_msg_t *)&vio_msg));
1885 }
1886 
1887 
1888 /* -------------------------------------------------------------------------- */
1889 
1890 /*
1891  * LDC helper routines
1892  */
1893 
1894 static int
1895 vdc_recv(vdc_t *vdc, vio_msg_t *msgp, size_t *nbytesp)
1896 {
1897 	int		status;
1898 	boolean_t	q_has_pkts = B_FALSE;
1899 	uint64_t	delay_time;
1900 	size_t		len;
1901 
1902 	mutex_enter(&vdc->read_lock);
1903 
1904 	if (vdc->read_state == VDC_READ_IDLE)
1905 		vdc->read_state = VDC_READ_WAITING;
1906 
1907 	while (vdc->read_state != VDC_READ_PENDING) {
1908 
1909 		/* detect if the connection has been reset */
1910 		if (vdc->read_state == VDC_READ_RESET) {
1911 			status = ECONNRESET;
1912 			goto done;
1913 		}
1914 
1915 		cv_wait(&vdc->read_cv, &vdc->read_lock);
1916 	}
1917 
1918 	/*
1919 	 * Until we get a blocking ldc read we have to retry
1920 	 * until the entire LDC message has arrived before
1921 	 * ldc_read() will succeed. Note we also bail out if
1922 	 * the channel is reset or goes away.
1923 	 */
1924 	delay_time = vdc_ldc_read_init_delay;
1925 loop:
1926 	len = *nbytesp;
1927 	status = ldc_read(vdc->ldc_handle, (caddr_t)msgp, &len);
1928 	switch (status) {
1929 	case EAGAIN:
1930 		delay_time *= 2;
1931 		if (delay_time >= vdc_ldc_read_max_delay)
1932 			delay_time = vdc_ldc_read_max_delay;
1933 		delay(delay_time);
1934 		goto loop;
1935 
1936 	case 0:
1937 		if (len == 0) {
1938 			DMSG(vdc, 1, "[%d] ldc_read returned 0 bytes with "
1939 			    "no error!\n", vdc->instance);
1940 			goto loop;
1941 		}
1942 
1943 		*nbytesp = len;
1944 
1945 		/*
1946 		 * If there are pending messages, leave the
1947 		 * read state as pending. Otherwise, set the state
1948 		 * back to idle.
1949 		 */
1950 		status = ldc_chkq(vdc->ldc_handle, &q_has_pkts);
1951 		if (status == 0 && !q_has_pkts)
1952 			vdc->read_state = VDC_READ_IDLE;
1953 
1954 		break;
1955 	default:
1956 		DMSG(vdc, 0, "ldc_read returned %d\n", status);
1957 		break;
1958 	}
1959 
1960 done:
1961 	mutex_exit(&vdc->read_lock);
1962 
1963 	return (status);
1964 }
1965 
1966 
1967 
1968 #ifdef DEBUG
1969 void
1970 vdc_decode_tag(vdc_t *vdcp, vio_msg_t *msg)
1971 {
1972 	char *ms, *ss, *ses;
1973 	switch (msg->tag.vio_msgtype) {
1974 #define	Q(_s)	case _s : ms = #_s; break;
1975 	Q(VIO_TYPE_CTRL)
1976 	Q(VIO_TYPE_DATA)
1977 	Q(VIO_TYPE_ERR)
1978 #undef Q
1979 	default: ms = "unknown"; break;
1980 	}
1981 
1982 	switch (msg->tag.vio_subtype) {
1983 #define	Q(_s)	case _s : ss = #_s; break;
1984 	Q(VIO_SUBTYPE_INFO)
1985 	Q(VIO_SUBTYPE_ACK)
1986 	Q(VIO_SUBTYPE_NACK)
1987 #undef Q
1988 	default: ss = "unknown"; break;
1989 	}
1990 
1991 	switch (msg->tag.vio_subtype_env) {
1992 #define	Q(_s)	case _s : ses = #_s; break;
1993 	Q(VIO_VER_INFO)
1994 	Q(VIO_ATTR_INFO)
1995 	Q(VIO_DRING_REG)
1996 	Q(VIO_DRING_UNREG)
1997 	Q(VIO_RDX)
1998 	Q(VIO_PKT_DATA)
1999 	Q(VIO_DESC_DATA)
2000 	Q(VIO_DRING_DATA)
2001 #undef Q
2002 	default: ses = "unknown"; break;
2003 	}
2004 
2005 	DMSG(vdcp, 3, "(%x/%x/%x) message : (%s/%s/%s)\n",
2006 	    msg->tag.vio_msgtype, msg->tag.vio_subtype,
2007 	    msg->tag.vio_subtype_env, ms, ss, ses);
2008 }
2009 #endif
2010 
2011 /*
2012  * Function:
2013  *	vdc_send()
2014  *
2015  * Description:
2016  *	The function encapsulates the call to write a message using LDC.
2017  *	If LDC indicates that the call failed due to the queue being full,
2018  *	we retry the ldc_write(), otherwise we return the error returned by LDC.
2019  *
2020  * Arguments:
2021  *	ldc_handle	- LDC handle for the channel this instance of vdc uses
2022  *	pkt		- address of LDC message to be sent
2023  *	msglen		- the size of the message being sent. When the function
2024  *			  returns, this contains the number of bytes written.
2025  *
2026  * Return Code:
2027  *	0		- Success.
2028  *	EINVAL		- pkt or msglen were NULL
2029  *	ECONNRESET	- The connection was not up.
2030  *	EWOULDBLOCK	- LDC queue is full
2031  *	xxx		- other error codes returned by ldc_write
2032  */
2033 static int
2034 vdc_send(vdc_t *vdc, caddr_t pkt, size_t *msglen)
2035 {
2036 	size_t	size = 0;
2037 	int	status = 0;
2038 	clock_t delay_ticks;
2039 
2040 	ASSERT(vdc != NULL);
2041 	ASSERT(mutex_owned(&vdc->lock));
2042 	ASSERT(msglen != NULL);
2043 	ASSERT(*msglen != 0);
2044 
2045 #ifdef DEBUG
2046 	vdc_decode_tag(vdc, (vio_msg_t *)(uintptr_t)pkt);
2047 #endif
2048 	/*
2049 	 * Wait indefinitely to send if channel
2050 	 * is busy, but bail out if we succeed or
2051 	 * if the channel closes or is reset.
2052 	 */
2053 	delay_ticks = vdc_hz_min_ldc_delay;
2054 	do {
2055 		size = *msglen;
2056 		status = ldc_write(vdc->ldc_handle, pkt, &size);
2057 		if (status == EWOULDBLOCK) {
2058 			delay(delay_ticks);
2059 			/* geometric backoff */
2060 			delay_ticks *= 2;
2061 			if (delay_ticks > vdc_hz_max_ldc_delay)
2062 				delay_ticks = vdc_hz_max_ldc_delay;
2063 		}
2064 	} while (status == EWOULDBLOCK);
2065 
2066 	/* if LDC had serious issues --- reset vdc state */
2067 	if (status == EIO || status == ECONNRESET) {
2068 		/* LDC had serious issues --- reset vdc state */
2069 		mutex_enter(&vdc->read_lock);
2070 		if ((vdc->read_state == VDC_READ_WAITING) ||
2071 		    (vdc->read_state == VDC_READ_RESET))
2072 			cv_signal(&vdc->read_cv);
2073 		vdc->read_state = VDC_READ_RESET;
2074 		mutex_exit(&vdc->read_lock);
2075 
2076 		/* wake up any waiters in the reset thread */
2077 		if (vdc->state == VDC_STATE_INIT_WAITING) {
2078 			DMSG(vdc, 0, "[%d] write reset - "
2079 			    "vdc is resetting ..\n", vdc->instance);
2080 			vdc->state = VDC_STATE_RESETTING;
2081 			cv_signal(&vdc->initwait_cv);
2082 		}
2083 
2084 		return (ECONNRESET);
2085 	}
2086 
2087 	/* return the last size written */
2088 	*msglen = size;
2089 
2090 	return (status);
2091 }
2092 
2093 /*
2094  * Function:
2095  *	vdc_get_md_node
2096  *
2097  * Description:
2098  *	Get the MD, the device node and the port node for the given
2099  *	disk instance. The caller is responsible for cleaning up the
2100  *	reference to the returned MD (mdpp) by calling md_fini_handle().
2101  *
2102  * Arguments:
2103  *	dip	- dev info pointer for this instance of the device driver.
2104  *	mdpp	- the returned MD.
2105  *	vd_nodep - the returned device node.
2106  *	vd_portp - the returned port node. The returned port node is NULL
2107  *		   if no port node is found.
2108  *
2109  * Return Code:
2110  *	0	- Success.
2111  *	ENOENT	- Expected node or property did not exist.
2112  *	ENXIO	- Unexpected error communicating with MD framework
2113  */
2114 static int
2115 vdc_get_md_node(dev_info_t *dip, md_t **mdpp, mde_cookie_t *vd_nodep,
2116     mde_cookie_t *vd_portp)
2117 {
2118 	int		status = ENOENT;
2119 	char		*node_name = NULL;
2120 	md_t		*mdp = NULL;
2121 	int		num_nodes;
2122 	int		num_vdevs;
2123 	int		num_vports;
2124 	mde_cookie_t	rootnode;
2125 	mde_cookie_t	*listp = NULL;
2126 	boolean_t	found_inst = B_FALSE;
2127 	int		listsz;
2128 	int		idx;
2129 	uint64_t	md_inst;
2130 	int		obp_inst;
2131 	int		instance = ddi_get_instance(dip);
2132 
2133 	/*
2134 	 * Get the OBP instance number for comparison with the MD instance
2135 	 *
2136 	 * The "cfg-handle" property of a vdc node in an MD contains the MD's
2137 	 * notion of "instance", or unique identifier, for that node; OBP
2138 	 * stores the value of the "cfg-handle" MD property as the value of
2139 	 * the "reg" property on the node in the device tree it builds from
2140 	 * the MD and passes to Solaris.  Thus, we look up the devinfo node's
2141 	 * "reg" property value to uniquely identify this device instance.
2142 	 * If the "reg" property cannot be found, the device tree state is
2143 	 * presumably so broken that there is no point in continuing.
2144 	 */
2145 	if (!ddi_prop_exists(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS, OBP_REG)) {
2146 		cmn_err(CE_WARN, "'%s' property does not exist", OBP_REG);
2147 		return (ENOENT);
2148 	}
2149 	obp_inst = ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
2150 	    OBP_REG, -1);
2151 	DMSGX(1, "[%d] OBP inst=%d\n", instance, obp_inst);
2152 
2153 	/*
2154 	 * We now walk the MD nodes to find the node for this vdisk.
2155 	 */
2156 	if ((mdp = md_get_handle()) == NULL) {
2157 		cmn_err(CE_WARN, "unable to init machine description");
2158 		return (ENXIO);
2159 	}
2160 
2161 	num_nodes = md_node_count(mdp);
2162 	ASSERT(num_nodes > 0);
2163 
2164 	listsz = num_nodes * sizeof (mde_cookie_t);
2165 
2166 	/* allocate memory for nodes */
2167 	listp = kmem_zalloc(listsz, KM_SLEEP);
2168 
2169 	rootnode = md_root_node(mdp);
2170 	ASSERT(rootnode != MDE_INVAL_ELEM_COOKIE);
2171 
2172 	/*
2173 	 * Search for all the virtual devices, we will then check to see which
2174 	 * ones are disk nodes.
2175 	 */
2176 	num_vdevs = md_scan_dag(mdp, rootnode,
2177 	    md_find_name(mdp, VDC_MD_VDEV_NAME),
2178 	    md_find_name(mdp, "fwd"), listp);
2179 
2180 	if (num_vdevs <= 0) {
2181 		cmn_err(CE_NOTE, "No '%s' node found", VDC_MD_VDEV_NAME);
2182 		status = ENOENT;
2183 		goto done;
2184 	}
2185 
2186 	DMSGX(1, "[%d] num_vdevs=%d\n", instance, num_vdevs);
2187 	for (idx = 0; idx < num_vdevs; idx++) {
2188 		status = md_get_prop_str(mdp, listp[idx], "name", &node_name);
2189 		if ((status != 0) || (node_name == NULL)) {
2190 			cmn_err(CE_NOTE, "Unable to get name of node type '%s'"
2191 			    ": err %d", VDC_MD_VDEV_NAME, status);
2192 			continue;
2193 		}
2194 
2195 		DMSGX(1, "[%d] Found node '%s'\n", instance, node_name);
2196 		if (strcmp(VDC_MD_DISK_NAME, node_name) == 0) {
2197 			status = md_get_prop_val(mdp, listp[idx],
2198 			    VDC_MD_CFG_HDL, &md_inst);
2199 			DMSGX(1, "[%d] vdc inst in MD=%lx\n",
2200 			    instance, md_inst);
2201 			if ((status == 0) && (md_inst == obp_inst)) {
2202 				found_inst = B_TRUE;
2203 				break;
2204 			}
2205 		}
2206 	}
2207 
2208 	if (!found_inst) {
2209 		DMSGX(0, "Unable to find correct '%s' node", VDC_MD_DISK_NAME);
2210 		status = ENOENT;
2211 		goto done;
2212 	}
2213 	DMSGX(0, "[%d] MD inst=%lx\n", instance, md_inst);
2214 
2215 	*vd_nodep = listp[idx];
2216 	*mdpp = mdp;
2217 
2218 	num_vports = md_scan_dag(mdp, *vd_nodep,
2219 	    md_find_name(mdp, VDC_MD_PORT_NAME),
2220 	    md_find_name(mdp, "fwd"), listp);
2221 
2222 	if (num_vports != 1) {
2223 		DMSGX(0, "Expected 1 '%s' node for '%s' port, found %d\n",
2224 		    VDC_MD_PORT_NAME, VDC_MD_VDEV_NAME, num_vports);
2225 	}
2226 
2227 	*vd_portp = (num_vports == 0)? NULL: listp[0];
2228 
2229 done:
2230 	kmem_free(listp, listsz);
2231 	return (status);
2232 }
2233 
2234 /*
2235  * Function:
2236  *	vdc_get_ldc_id()
2237  *
2238  * Description:
2239  *	This function gets the 'ldc-id' for this particular instance of vdc.
2240  *	The id returned is the guest domain channel endpoint LDC uses for
2241  *	communication with vds.
2242  *
2243  * Arguments:
2244  *	mdp	- pointer to the machine description.
2245  *	vd_node	- the vdisk element from the MD.
2246  *	ldc_id	- pointer to variable used to return the 'ldc-id' found.
2247  *
2248  * Return Code:
2249  *	0	- Success.
2250  *	ENOENT	- Expected node or property did not exist.
2251  */
2252 static int
2253 vdc_get_ldc_id(md_t *mdp, mde_cookie_t vd_node, uint64_t *ldc_id)
2254 {
2255 	mde_cookie_t	*chanp = NULL;
2256 	int		listsz;
2257 	int		num_chans;
2258 	int		num_nodes;
2259 	int		status = 0;
2260 
2261 	num_nodes = md_node_count(mdp);
2262 	ASSERT(num_nodes > 0);
2263 
2264 	listsz = num_nodes * sizeof (mde_cookie_t);
2265 
2266 	/* allocate memory for nodes */
2267 	chanp = kmem_zalloc(listsz, KM_SLEEP);
2268 
2269 	/* get the channels for this node */
2270 	num_chans = md_scan_dag(mdp, vd_node,
2271 	    md_find_name(mdp, VDC_MD_CHAN_NAME),
2272 	    md_find_name(mdp, "fwd"), chanp);
2273 
2274 	/* expecting at least one channel */
2275 	if (num_chans <= 0) {
2276 		cmn_err(CE_NOTE, "No '%s' node for '%s' port",
2277 		    VDC_MD_CHAN_NAME, VDC_MD_VDEV_NAME);
2278 		status = ENOENT;
2279 		goto done;
2280 
2281 	} else if (num_chans != 1) {
2282 		DMSGX(0, "Expected 1 '%s' node for '%s' port, found %d\n",
2283 		    VDC_MD_CHAN_NAME, VDC_MD_VDEV_NAME, num_chans);
2284 	}
2285 
2286 	/*
2287 	 * We use the first channel found (index 0), irrespective of how
2288 	 * many are there in total.
2289 	 */
2290 	if (md_get_prop_val(mdp, chanp[0], VDC_MD_ID, ldc_id) != 0) {
2291 		cmn_err(CE_NOTE, "Channel '%s' property not found", VDC_MD_ID);
2292 		status = ENOENT;
2293 	}
2294 
2295 done:
2296 	kmem_free(chanp, listsz);
2297 	return (status);
2298 }
2299 
2300 static int
2301 vdc_do_ldc_up(vdc_t *vdc)
2302 {
2303 	int		status;
2304 	ldc_status_t	ldc_state;
2305 
2306 	DMSG(vdc, 0, "[%d] Bringing up channel %lx\n",
2307 	    vdc->instance, vdc->ldc_id);
2308 
2309 	if (vdc->lifecycle == VDC_LC_DETACHING)
2310 		return (EINVAL);
2311 
2312 	if ((status = ldc_up(vdc->ldc_handle)) != 0) {
2313 		switch (status) {
2314 		case ECONNREFUSED:	/* listener not ready at other end */
2315 			DMSG(vdc, 0, "[%d] ldc_up(%lx,...) return %d\n",
2316 			    vdc->instance, vdc->ldc_id, status);
2317 			status = 0;
2318 			break;
2319 		default:
2320 			DMSG(vdc, 0, "[%d] Failed to bring up LDC: "
2321 			    "channel=%ld, err=%d", vdc->instance, vdc->ldc_id,
2322 			    status);
2323 			break;
2324 		}
2325 	}
2326 
2327 	if (ldc_status(vdc->ldc_handle, &ldc_state) == 0) {
2328 		vdc->ldc_state = ldc_state;
2329 		if (ldc_state == LDC_UP) {
2330 			DMSG(vdc, 0, "[%d] LDC channel already up\n",
2331 			    vdc->instance);
2332 			vdc->seq_num = 1;
2333 			vdc->seq_num_reply = 0;
2334 		}
2335 	}
2336 
2337 	return (status);
2338 }
2339 
2340 /*
2341  * Function:
2342  *	vdc_terminate_ldc()
2343  *
2344  * Description:
2345  *
2346  * Arguments:
2347  *	vdc	- soft state pointer for this instance of the device driver.
2348  *
2349  * Return Code:
2350  *	None
2351  */
2352 static void
2353 vdc_terminate_ldc(vdc_t *vdc)
2354 {
2355 	int	instance = ddi_get_instance(vdc->dip);
2356 
2357 	ASSERT(vdc != NULL);
2358 	ASSERT(mutex_owned(&vdc->lock));
2359 
2360 	DMSG(vdc, 0, "[%d] initialized=%x\n", instance, vdc->initialized);
2361 
2362 	if (vdc->initialized & VDC_LDC_OPEN) {
2363 		DMSG(vdc, 0, "[%d] ldc_close()\n", instance);
2364 		(void) ldc_close(vdc->ldc_handle);
2365 	}
2366 	if (vdc->initialized & VDC_LDC_CB) {
2367 		DMSG(vdc, 0, "[%d] ldc_unreg_callback()\n", instance);
2368 		(void) ldc_unreg_callback(vdc->ldc_handle);
2369 	}
2370 	if (vdc->initialized & VDC_LDC) {
2371 		DMSG(vdc, 0, "[%d] ldc_fini()\n", instance);
2372 		(void) ldc_fini(vdc->ldc_handle);
2373 		vdc->ldc_handle = NULL;
2374 	}
2375 
2376 	vdc->initialized &= ~(VDC_LDC | VDC_LDC_CB | VDC_LDC_OPEN);
2377 }
2378 
2379 /* -------------------------------------------------------------------------- */
2380 
2381 /*
2382  * Descriptor Ring helper routines
2383  */
2384 
2385 /*
2386  * Function:
2387  *	vdc_init_descriptor_ring()
2388  *
2389  * Description:
2390  *
2391  * Arguments:
2392  *	vdc	- soft state pointer for this instance of the device driver.
2393  *
2394  * Return Code:
2395  *	0	- Success
2396  */
2397 static int
2398 vdc_init_descriptor_ring(vdc_t *vdc)
2399 {
2400 	vd_dring_entry_t	*dep = NULL;	/* DRing Entry pointer */
2401 	int	status = 0;
2402 	int	i;
2403 
2404 	DMSG(vdc, 0, "[%d] initialized=%x\n", vdc->instance, vdc->initialized);
2405 
2406 	ASSERT(vdc != NULL);
2407 	ASSERT(mutex_owned(&vdc->lock));
2408 	ASSERT(vdc->ldc_handle != NULL);
2409 
2410 	/* ensure we have enough room to store max sized block */
2411 	ASSERT(maxphys <= VD_MAX_BLOCK_SIZE);
2412 
2413 	if ((vdc->initialized & VDC_DRING_INIT) == 0) {
2414 		DMSG(vdc, 0, "[%d] ldc_mem_dring_create\n", vdc->instance);
2415 		/*
2416 		 * Calculate the maximum block size we can transmit using one
2417 		 * Descriptor Ring entry from the attributes returned by the
2418 		 * vDisk server. This is subject to a minimum of 'maxphys'
2419 		 * as we do not have the capability to split requests over
2420 		 * multiple DRing entries.
2421 		 */
2422 		if ((vdc->max_xfer_sz * vdc->block_size) < maxphys) {
2423 			DMSG(vdc, 0, "[%d] using minimum DRing size\n",
2424 			    vdc->instance);
2425 			vdc->dring_max_cookies = maxphys / PAGESIZE;
2426 		} else {
2427 			vdc->dring_max_cookies =
2428 			    (vdc->max_xfer_sz * vdc->block_size) / PAGESIZE;
2429 		}
2430 		vdc->dring_entry_size = (sizeof (vd_dring_entry_t) +
2431 		    (sizeof (ldc_mem_cookie_t) *
2432 		    (vdc->dring_max_cookies - 1)));
2433 		vdc->dring_len = VD_DRING_LEN;
2434 
2435 		status = ldc_mem_dring_create(vdc->dring_len,
2436 		    vdc->dring_entry_size, &vdc->ldc_dring_hdl);
2437 		if ((vdc->ldc_dring_hdl == NULL) || (status != 0)) {
2438 			DMSG(vdc, 0, "[%d] Descriptor ring creation failed",
2439 			    vdc->instance);
2440 			return (status);
2441 		}
2442 		vdc->initialized |= VDC_DRING_INIT;
2443 	}
2444 
2445 	if ((vdc->initialized & VDC_DRING_BOUND) == 0) {
2446 		DMSG(vdc, 0, "[%d] ldc_mem_dring_bind\n", vdc->instance);
2447 		vdc->dring_cookie =
2448 		    kmem_zalloc(sizeof (ldc_mem_cookie_t), KM_SLEEP);
2449 
2450 		status = ldc_mem_dring_bind(vdc->ldc_handle, vdc->ldc_dring_hdl,
2451 		    LDC_SHADOW_MAP|LDC_DIRECT_MAP, LDC_MEM_RW,
2452 		    &vdc->dring_cookie[0],
2453 		    &vdc->dring_cookie_count);
2454 		if (status != 0) {
2455 			DMSG(vdc, 0, "[%d] Failed to bind descriptor ring "
2456 			    "(%lx) to channel (%lx) status=%d\n",
2457 			    vdc->instance, vdc->ldc_dring_hdl,
2458 			    vdc->ldc_handle, status);
2459 			return (status);
2460 		}
2461 		ASSERT(vdc->dring_cookie_count == 1);
2462 		vdc->initialized |= VDC_DRING_BOUND;
2463 	}
2464 
2465 	status = ldc_mem_dring_info(vdc->ldc_dring_hdl, &vdc->dring_mem_info);
2466 	if (status != 0) {
2467 		DMSG(vdc, 0,
2468 		    "[%d] Failed to get info for descriptor ring (%lx)\n",
2469 		    vdc->instance, vdc->ldc_dring_hdl);
2470 		return (status);
2471 	}
2472 
2473 	if ((vdc->initialized & VDC_DRING_LOCAL) == 0) {
2474 		DMSG(vdc, 0, "[%d] local dring\n", vdc->instance);
2475 
2476 		/* Allocate the local copy of this dring */
2477 		vdc->local_dring =
2478 		    kmem_zalloc(vdc->dring_len * sizeof (vdc_local_desc_t),
2479 		    KM_SLEEP);
2480 		vdc->initialized |= VDC_DRING_LOCAL;
2481 	}
2482 
2483 	/*
2484 	 * Mark all DRing entries as free and initialize the private
2485 	 * descriptor's memory handles. If any entry is initialized,
2486 	 * we need to free it later so we set the bit in 'initialized'
2487 	 * at the start.
2488 	 */
2489 	vdc->initialized |= VDC_DRING_ENTRY;
2490 	for (i = 0; i < vdc->dring_len; i++) {
2491 		dep = VDC_GET_DRING_ENTRY_PTR(vdc, i);
2492 		dep->hdr.dstate = VIO_DESC_FREE;
2493 
2494 		status = ldc_mem_alloc_handle(vdc->ldc_handle,
2495 		    &vdc->local_dring[i].desc_mhdl);
2496 		if (status != 0) {
2497 			DMSG(vdc, 0, "![%d] Failed to alloc mem handle for"
2498 			    " descriptor %d", vdc->instance, i);
2499 			return (status);
2500 		}
2501 		vdc->local_dring[i].is_free = B_TRUE;
2502 		vdc->local_dring[i].dep = dep;
2503 	}
2504 
2505 	/* Initialize the starting index */
2506 	vdc->dring_curr_idx = 0;
2507 
2508 	return (status);
2509 }
2510 
2511 /*
2512  * Function:
2513  *	vdc_destroy_descriptor_ring()
2514  *
2515  * Description:
2516  *
2517  * Arguments:
2518  *	vdc	- soft state pointer for this instance of the device driver.
2519  *
2520  * Return Code:
2521  *	None
2522  */
2523 static void
2524 vdc_destroy_descriptor_ring(vdc_t *vdc)
2525 {
2526 	vdc_local_desc_t	*ldep = NULL;	/* Local Dring Entry Pointer */
2527 	ldc_mem_handle_t	mhdl = NULL;
2528 	ldc_mem_info_t		minfo;
2529 	int			status = -1;
2530 	int			i;	/* loop */
2531 
2532 	ASSERT(vdc != NULL);
2533 	ASSERT(mutex_owned(&vdc->lock));
2534 
2535 	DMSG(vdc, 0, "[%d] Entered\n", vdc->instance);
2536 
2537 	if (vdc->initialized & VDC_DRING_ENTRY) {
2538 		DMSG(vdc, 0,
2539 		    "[%d] Removing Local DRing entries\n", vdc->instance);
2540 		for (i = 0; i < vdc->dring_len; i++) {
2541 			ldep = &vdc->local_dring[i];
2542 			mhdl = ldep->desc_mhdl;
2543 
2544 			if (mhdl == NULL)
2545 				continue;
2546 
2547 			if ((status = ldc_mem_info(mhdl, &minfo)) != 0) {
2548 				DMSG(vdc, 0,
2549 				    "ldc_mem_info returned an error: %d\n",
2550 				    status);
2551 
2552 				/*
2553 				 * This must mean that the mem handle
2554 				 * is not valid. Clear it out so that
2555 				 * no one tries to use it.
2556 				 */
2557 				ldep->desc_mhdl = NULL;
2558 				continue;
2559 			}
2560 
2561 			if (minfo.status == LDC_BOUND) {
2562 				(void) ldc_mem_unbind_handle(mhdl);
2563 			}
2564 
2565 			(void) ldc_mem_free_handle(mhdl);
2566 
2567 			ldep->desc_mhdl = NULL;
2568 		}
2569 		vdc->initialized &= ~VDC_DRING_ENTRY;
2570 	}
2571 
2572 	if (vdc->initialized & VDC_DRING_LOCAL) {
2573 		DMSG(vdc, 0, "[%d] Freeing Local DRing\n", vdc->instance);
2574 		kmem_free(vdc->local_dring,
2575 		    vdc->dring_len * sizeof (vdc_local_desc_t));
2576 		vdc->initialized &= ~VDC_DRING_LOCAL;
2577 	}
2578 
2579 	if (vdc->initialized & VDC_DRING_BOUND) {
2580 		DMSG(vdc, 0, "[%d] Unbinding DRing\n", vdc->instance);
2581 		status = ldc_mem_dring_unbind(vdc->ldc_dring_hdl);
2582 		if (status == 0) {
2583 			vdc->initialized &= ~VDC_DRING_BOUND;
2584 		} else {
2585 			DMSG(vdc, 0, "[%d] Error %d unbinding DRing %lx",
2586 			    vdc->instance, status, vdc->ldc_dring_hdl);
2587 		}
2588 		kmem_free(vdc->dring_cookie, sizeof (ldc_mem_cookie_t));
2589 	}
2590 
2591 	if (vdc->initialized & VDC_DRING_INIT) {
2592 		DMSG(vdc, 0, "[%d] Destroying DRing\n", vdc->instance);
2593 		status = ldc_mem_dring_destroy(vdc->ldc_dring_hdl);
2594 		if (status == 0) {
2595 			vdc->ldc_dring_hdl = NULL;
2596 			bzero(&vdc->dring_mem_info, sizeof (ldc_mem_info_t));
2597 			vdc->initialized &= ~VDC_DRING_INIT;
2598 		} else {
2599 			DMSG(vdc, 0, "[%d] Error %d destroying DRing (%lx)",
2600 			    vdc->instance, status, vdc->ldc_dring_hdl);
2601 		}
2602 	}
2603 }
2604 
2605 /*
2606  * Function:
2607  *	vdc_map_to_shared_ring()
2608  *
2609  * Description:
2610  *	Copy contents of the local descriptor to the shared
2611  *	memory descriptor.
2612  *
2613  * Arguments:
2614  *	vdcp	- soft state pointer for this instance of the device driver.
2615  *	idx	- descriptor ring index
2616  *
2617  * Return Code:
2618  *	None
2619  */
2620 static int
2621 vdc_map_to_shared_dring(vdc_t *vdcp, int idx)
2622 {
2623 	vdc_local_desc_t	*ldep;
2624 	vd_dring_entry_t	*dep;
2625 	int			rv;
2626 
2627 	ldep = &(vdcp->local_dring[idx]);
2628 
2629 	/* for now leave in the old pop_mem_hdl stuff */
2630 	if (ldep->nbytes > 0) {
2631 		rv = vdc_populate_mem_hdl(vdcp, ldep);
2632 		if (rv) {
2633 			DMSG(vdcp, 0, "[%d] Cannot populate mem handle\n",
2634 			    vdcp->instance);
2635 			return (rv);
2636 		}
2637 	}
2638 
2639 	/*
2640 	 * fill in the data details into the DRing
2641 	 */
2642 	dep = ldep->dep;
2643 	ASSERT(dep != NULL);
2644 
2645 	dep->payload.req_id = VDC_GET_NEXT_REQ_ID(vdcp);
2646 	dep->payload.operation = ldep->operation;
2647 	dep->payload.addr = ldep->offset;
2648 	dep->payload.nbytes = ldep->nbytes;
2649 	dep->payload.status = (uint32_t)-1;	/* vds will set valid value */
2650 	dep->payload.slice = ldep->slice;
2651 	dep->hdr.dstate = VIO_DESC_READY;
2652 	dep->hdr.ack = 1;		/* request an ACK for every message */
2653 
2654 	return (0);
2655 }
2656 
2657 /*
2658  * Function:
2659  *	vdc_send_request
2660  *
2661  * Description:
2662  *	This routine writes the data to be transmitted to vds into the
2663  *	descriptor, notifies vds that the ring has been updated and
2664  *	then waits for the request to be processed.
2665  *
2666  * Arguments:
2667  *	vdcp	  - the soft state pointer
2668  *	operation - operation we want vds to perform (VD_OP_XXX)
2669  *	addr	  - address of data buf to be read/written.
2670  *	nbytes	  - number of bytes to read/write
2671  *	slice	  - the disk slice this request is for
2672  *	offset	  - relative disk offset
2673  *	cb_type   - type of call - STRATEGY or SYNC
2674  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2675  *			. mode for ioctl(9e)
2676  *			. LP64 diskaddr_t (block I/O)
2677  *	dir	  - direction of operation (READ/WRITE/BOTH)
2678  *
2679  * Return Codes:
2680  *	0
2681  *	ENXIO
2682  */
2683 static int
2684 vdc_send_request(vdc_t *vdcp, int operation, caddr_t addr,
2685     size_t nbytes, int slice, diskaddr_t offset, int cb_type,
2686     void *cb_arg, vio_desc_direction_t dir)
2687 {
2688 	ASSERT(vdcp != NULL);
2689 	ASSERT(slice == VD_SLICE_NONE || slice < V_NUMPAR);
2690 
2691 	mutex_enter(&vdcp->lock);
2692 
2693 	do {
2694 		while (vdcp->state != VDC_STATE_RUNNING) {
2695 
2696 			/* return error if detaching */
2697 			if (vdcp->state == VDC_STATE_DETACH) {
2698 				mutex_exit(&vdcp->lock);
2699 				return (ENXIO);
2700 			}
2701 
2702 			/* fail request if connection timeout is reached */
2703 			if (vdcp->ctimeout_reached) {
2704 				mutex_exit(&vdcp->lock);
2705 				return (EIO);
2706 			}
2707 
2708 			/*
2709 			 * If we are panicking and the disk is not ready then
2710 			 * we can't send any request because we can't complete
2711 			 * the handshake now.
2712 			 */
2713 			if (ddi_in_panic()) {
2714 				mutex_exit(&vdcp->lock);
2715 				return (EIO);
2716 			}
2717 
2718 			cv_wait(&vdcp->running_cv, &vdcp->lock);
2719 		}
2720 
2721 	} while (vdc_populate_descriptor(vdcp, operation, addr,
2722 	    nbytes, slice, offset, cb_type, cb_arg, dir));
2723 
2724 	mutex_exit(&vdcp->lock);
2725 	return (0);
2726 }
2727 
2728 
2729 /*
2730  * Function:
2731  *	vdc_populate_descriptor
2732  *
2733  * Description:
2734  *	This routine writes the data to be transmitted to vds into the
2735  *	descriptor, notifies vds that the ring has been updated and
2736  *	then waits for the request to be processed.
2737  *
2738  * Arguments:
2739  *	vdcp	  - the soft state pointer
2740  *	operation - operation we want vds to perform (VD_OP_XXX)
2741  *	addr	  - address of data buf to be read/written.
2742  *	nbytes	  - number of bytes to read/write
2743  *	slice	  - the disk slice this request is for
2744  *	offset	  - relative disk offset
2745  *	cb_type   - type of call - STRATEGY or SYNC
2746  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2747  *			. mode for ioctl(9e)
2748  *			. LP64 diskaddr_t (block I/O)
2749  *	dir	  - direction of operation (READ/WRITE/BOTH)
2750  *
2751  * Return Codes:
2752  *	0
2753  *	EAGAIN
2754  *	ECONNRESET
2755  *	ENXIO
2756  */
2757 static int
2758 vdc_populate_descriptor(vdc_t *vdcp, int operation, caddr_t addr,
2759     size_t nbytes, int slice, diskaddr_t offset, int cb_type,
2760     void *cb_arg, vio_desc_direction_t dir)
2761 {
2762 	vdc_local_desc_t	*local_dep = NULL; /* Local Dring Pointer */
2763 	int			idx;		/* Index of DRing entry used */
2764 	int			next_idx;
2765 	vio_dring_msg_t		dmsg;
2766 	size_t			msglen;
2767 	int			rv;
2768 
2769 	ASSERT(MUTEX_HELD(&vdcp->lock));
2770 	vdcp->threads_pending++;
2771 loop:
2772 	DMSG(vdcp, 2, ": dring_curr_idx = %d\n", vdcp->dring_curr_idx);
2773 
2774 	/* Get next available D-Ring entry */
2775 	idx = vdcp->dring_curr_idx;
2776 	local_dep = &(vdcp->local_dring[idx]);
2777 
2778 	if (!local_dep->is_free) {
2779 		DMSG(vdcp, 2, "[%d]: dring full - waiting for space\n",
2780 		    vdcp->instance);
2781 		cv_wait(&vdcp->dring_free_cv, &vdcp->lock);
2782 		if (vdcp->state == VDC_STATE_RUNNING ||
2783 		    vdcp->state == VDC_STATE_HANDLE_PENDING) {
2784 			goto loop;
2785 		}
2786 		vdcp->threads_pending--;
2787 		return (ECONNRESET);
2788 	}
2789 
2790 	next_idx = idx + 1;
2791 	if (next_idx >= vdcp->dring_len)
2792 		next_idx = 0;
2793 	vdcp->dring_curr_idx = next_idx;
2794 
2795 	ASSERT(local_dep->is_free);
2796 
2797 	local_dep->operation = operation;
2798 	local_dep->addr = addr;
2799 	local_dep->nbytes = nbytes;
2800 	local_dep->slice = slice;
2801 	local_dep->offset = offset;
2802 	local_dep->cb_type = cb_type;
2803 	local_dep->cb_arg = cb_arg;
2804 	local_dep->dir = dir;
2805 
2806 	local_dep->is_free = B_FALSE;
2807 
2808 	rv = vdc_map_to_shared_dring(vdcp, idx);
2809 	if (rv) {
2810 		DMSG(vdcp, 0, "[%d]: cannot bind memory - waiting ..\n",
2811 		    vdcp->instance);
2812 		/* free the descriptor */
2813 		local_dep->is_free = B_TRUE;
2814 		vdcp->dring_curr_idx = idx;
2815 		cv_wait(&vdcp->membind_cv, &vdcp->lock);
2816 		if (vdcp->state == VDC_STATE_RUNNING ||
2817 		    vdcp->state == VDC_STATE_HANDLE_PENDING) {
2818 			goto loop;
2819 		}
2820 		vdcp->threads_pending--;
2821 		return (ECONNRESET);
2822 	}
2823 
2824 	/*
2825 	 * Send a msg with the DRing details to vds
2826 	 */
2827 	VIO_INIT_DRING_DATA_TAG(dmsg);
2828 	VDC_INIT_DRING_DATA_MSG_IDS(dmsg, vdcp);
2829 	dmsg.dring_ident = vdcp->dring_ident;
2830 	dmsg.start_idx = idx;
2831 	dmsg.end_idx = idx;
2832 	vdcp->seq_num++;
2833 
2834 	DTRACE_IO2(send, vio_dring_msg_t *, &dmsg, vdc_t *, vdcp);
2835 
2836 	DMSG(vdcp, 2, "ident=0x%lx, st=%u, end=%u, seq=%ld\n",
2837 	    vdcp->dring_ident, dmsg.start_idx, dmsg.end_idx, dmsg.seq_num);
2838 
2839 	/*
2840 	 * note we're still holding the lock here to
2841 	 * make sure the message goes out in order !!!...
2842 	 */
2843 	msglen = sizeof (dmsg);
2844 	rv = vdc_send(vdcp, (caddr_t)&dmsg, &msglen);
2845 	switch (rv) {
2846 	case ECONNRESET:
2847 		/*
2848 		 * vdc_send initiates the reset on failure.
2849 		 * Since the transaction has already been put
2850 		 * on the local dring, it will automatically get
2851 		 * retried when the channel is reset. Given that,
2852 		 * it is ok to just return success even though the
2853 		 * send failed.
2854 		 */
2855 		rv = 0;
2856 		break;
2857 
2858 	case 0: /* EOK */
2859 		DMSG(vdcp, 1, "sent via LDC: rv=%d\n", rv);
2860 		break;
2861 
2862 	default:
2863 		goto cleanup_and_exit;
2864 	}
2865 
2866 	vdcp->threads_pending--;
2867 	return (rv);
2868 
2869 cleanup_and_exit:
2870 	DMSG(vdcp, 0, "unexpected error, rv=%d\n", rv);
2871 	return (ENXIO);
2872 }
2873 
2874 /*
2875  * Function:
2876  *	vdc_do_sync_op
2877  *
2878  * Description:
2879  * 	Wrapper around vdc_populate_descriptor that blocks until the
2880  * 	response to the message is available.
2881  *
2882  * Arguments:
2883  *	vdcp	  - the soft state pointer
2884  *	operation - operation we want vds to perform (VD_OP_XXX)
2885  *	addr	  - address of data buf to be read/written.
2886  *	nbytes	  - number of bytes to read/write
2887  *	slice	  - the disk slice this request is for
2888  *	offset	  - relative disk offset
2889  *	cb_type   - type of call - STRATEGY or SYNC
2890  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2891  *			. mode for ioctl(9e)
2892  *			. LP64 diskaddr_t (block I/O)
2893  *	dir	  - direction of operation (READ/WRITE/BOTH)
2894  *	rconflict - check for reservation conflict in case of failure
2895  *
2896  * rconflict should be set to B_TRUE by most callers. Callers invoking the
2897  * VD_OP_SCSICMD operation can set rconflict to B_FALSE if they check the
2898  * result of a successful operation with vd_scsi_status().
2899  *
2900  * Return Codes:
2901  *	0
2902  *	EAGAIN
2903  *	EFAULT
2904  *	ENXIO
2905  *	EIO
2906  */
2907 static int
2908 vdc_do_sync_op(vdc_t *vdcp, int operation, caddr_t addr, size_t nbytes,
2909     int slice, diskaddr_t offset, int cb_type, void *cb_arg,
2910     vio_desc_direction_t dir, boolean_t rconflict)
2911 {
2912 	int status;
2913 	vdc_io_t *vio;
2914 	boolean_t check_resv_conflict = B_FALSE;
2915 
2916 	ASSERT(cb_type == CB_SYNC);
2917 
2918 	/*
2919 	 * Grab the lock, if blocked wait until the server
2920 	 * response causes us to wake up again.
2921 	 */
2922 	mutex_enter(&vdcp->lock);
2923 	vdcp->sync_op_cnt++;
2924 	while (vdcp->sync_op_blocked && vdcp->state != VDC_STATE_DETACH)
2925 		cv_wait(&vdcp->sync_blocked_cv, &vdcp->lock);
2926 
2927 	if (vdcp->state == VDC_STATE_DETACH) {
2928 		cv_broadcast(&vdcp->sync_blocked_cv);
2929 		vdcp->sync_op_cnt--;
2930 		mutex_exit(&vdcp->lock);
2931 		return (ENXIO);
2932 	}
2933 
2934 	/* now block anyone other thread entering after us */
2935 	vdcp->sync_op_blocked = B_TRUE;
2936 	vdcp->sync_op_pending = B_TRUE;
2937 	mutex_exit(&vdcp->lock);
2938 
2939 	status = vdc_send_request(vdcp, operation, addr,
2940 	    nbytes, slice, offset, cb_type, cb_arg, dir);
2941 
2942 	mutex_enter(&vdcp->lock);
2943 
2944 	if (status != 0) {
2945 		vdcp->sync_op_pending = B_FALSE;
2946 	} else {
2947 		/*
2948 		 * block until our transaction completes.
2949 		 * Also anyone else waiting also gets to go next.
2950 		 */
2951 		while (vdcp->sync_op_pending && vdcp->state != VDC_STATE_DETACH)
2952 			cv_wait(&vdcp->sync_pending_cv, &vdcp->lock);
2953 
2954 		DMSG(vdcp, 2, ": operation returned %d\n",
2955 		    vdcp->sync_op_status);
2956 		if (vdcp->state == VDC_STATE_DETACH) {
2957 			vdcp->sync_op_pending = B_FALSE;
2958 			status = ENXIO;
2959 		} else {
2960 			status = vdcp->sync_op_status;
2961 			if (status != 0 && vdcp->failfast_interval != 0) {
2962 				/*
2963 				 * Operation has failed and failfast is enabled.
2964 				 * We need to check if the failure is due to a
2965 				 * reservation conflict if this was requested.
2966 				 */
2967 				check_resv_conflict = rconflict;
2968 			}
2969 
2970 		}
2971 	}
2972 
2973 	vdcp->sync_op_status = 0;
2974 	vdcp->sync_op_blocked = B_FALSE;
2975 	vdcp->sync_op_cnt--;
2976 
2977 	/* signal the next waiting thread */
2978 	cv_signal(&vdcp->sync_blocked_cv);
2979 
2980 	/*
2981 	 * We have to check for reservation conflict after unblocking sync
2982 	 * operations because some sync operations will be used to do this
2983 	 * check.
2984 	 */
2985 	if (check_resv_conflict) {
2986 		vio = vdc_failfast_io_queue(vdcp, NULL);
2987 		while (vio->vio_qtime != 0)
2988 			cv_wait(&vdcp->failfast_io_cv, &vdcp->lock);
2989 		kmem_free(vio, sizeof (vdc_io_t));
2990 	}
2991 
2992 	mutex_exit(&vdcp->lock);
2993 
2994 	return (status);
2995 }
2996 
2997 
2998 /*
2999  * Function:
3000  *	vdc_drain_response()
3001  *
3002  * Description:
3003  * 	When a guest is panicking, the completion of requests needs to be
3004  * 	handled differently because interrupts are disabled and vdc
3005  * 	will not get messages. We have to poll for the messages instead.
3006  *
3007  * Arguments:
3008  *	vdc	- soft state pointer for this instance of the device driver.
3009  *
3010  * Return Code:
3011  *	0	- Success
3012  */
3013 static int
3014 vdc_drain_response(vdc_t *vdc)
3015 {
3016 	int 			rv, idx, retries;
3017 	size_t			msglen;
3018 	vdc_local_desc_t 	*ldep = NULL;	/* Local Dring Entry Pointer */
3019 	vio_dring_msg_t		dmsg;
3020 
3021 	mutex_enter(&vdc->lock);
3022 
3023 	retries = 0;
3024 	for (;;) {
3025 		msglen = sizeof (dmsg);
3026 		rv = ldc_read(vdc->ldc_handle, (caddr_t)&dmsg, &msglen);
3027 		if (rv) {
3028 			rv = EINVAL;
3029 			break;
3030 		}
3031 
3032 		/*
3033 		 * if there are no packets wait and check again
3034 		 */
3035 		if ((rv == 0) && (msglen == 0)) {
3036 			if (retries++ > vdc_dump_retries) {
3037 				rv = EAGAIN;
3038 				break;
3039 			}
3040 
3041 			drv_usecwait(vdc_usec_timeout_dump);
3042 			continue;
3043 		}
3044 
3045 		/*
3046 		 * Ignore all messages that are not ACKs/NACKs to
3047 		 * DRing requests.
3048 		 */
3049 		if ((dmsg.tag.vio_msgtype != VIO_TYPE_DATA) ||
3050 		    (dmsg.tag.vio_subtype_env != VIO_DRING_DATA)) {
3051 			DMSG(vdc, 0, "discard pkt: type=%d sub=%d env=%d\n",
3052 			    dmsg.tag.vio_msgtype,
3053 			    dmsg.tag.vio_subtype,
3054 			    dmsg.tag.vio_subtype_env);
3055 			continue;
3056 		}
3057 
3058 		/*
3059 		 * set the appropriate return value for the current request.
3060 		 */
3061 		switch (dmsg.tag.vio_subtype) {
3062 		case VIO_SUBTYPE_ACK:
3063 			rv = 0;
3064 			break;
3065 		case VIO_SUBTYPE_NACK:
3066 			rv = EAGAIN;
3067 			break;
3068 		default:
3069 			continue;
3070 		}
3071 
3072 		idx = dmsg.start_idx;
3073 		if (idx >= vdc->dring_len) {
3074 			DMSG(vdc, 0, "[%d] Bogus ack data : start %d\n",
3075 			    vdc->instance, idx);
3076 			continue;
3077 		}
3078 		ldep = &vdc->local_dring[idx];
3079 		if (ldep->dep->hdr.dstate != VIO_DESC_DONE) {
3080 			DMSG(vdc, 0, "[%d] Entry @ %d - state !DONE %d\n",
3081 			    vdc->instance, idx, ldep->dep->hdr.dstate);
3082 			continue;
3083 		}
3084 
3085 		DMSG(vdc, 1, "[%d] Depopulating idx=%d state=%d\n",
3086 		    vdc->instance, idx, ldep->dep->hdr.dstate);
3087 		rv = vdc_depopulate_descriptor(vdc, idx);
3088 		if (rv) {
3089 			DMSG(vdc, 0,
3090 			    "[%d] Entry @ %d - depopulate failed ..\n",
3091 			    vdc->instance, idx);
3092 		}
3093 
3094 		/* if this is the last descriptor - break out of loop */
3095 		if ((idx + 1) % vdc->dring_len == vdc->dring_curr_idx)
3096 			break;
3097 	}
3098 
3099 	mutex_exit(&vdc->lock);
3100 	DMSG(vdc, 0, "End idx=%d\n", idx);
3101 
3102 	return (rv);
3103 }
3104 
3105 
3106 /*
3107  * Function:
3108  *	vdc_depopulate_descriptor()
3109  *
3110  * Description:
3111  *
3112  * Arguments:
3113  *	vdc	- soft state pointer for this instance of the device driver.
3114  *	idx	- Index of the Descriptor Ring entry being modified
3115  *
3116  * Return Code:
3117  *	0	- Success
3118  */
3119 static int
3120 vdc_depopulate_descriptor(vdc_t *vdc, uint_t idx)
3121 {
3122 	vd_dring_entry_t *dep = NULL;		/* Dring Entry Pointer */
3123 	vdc_local_desc_t *ldep = NULL;		/* Local Dring Entry Pointer */
3124 	int		status = ENXIO;
3125 	int		rv = 0;
3126 
3127 	ASSERT(vdc != NULL);
3128 	ASSERT(idx < vdc->dring_len);
3129 	ldep = &vdc->local_dring[idx];
3130 	ASSERT(ldep != NULL);
3131 	ASSERT(MUTEX_HELD(&vdc->lock));
3132 
3133 	DMSG(vdc, 2, ": idx = %d\n", idx);
3134 	dep = ldep->dep;
3135 	ASSERT(dep != NULL);
3136 	ASSERT((dep->hdr.dstate == VIO_DESC_DONE) ||
3137 	    (dep->payload.status == ECANCELED));
3138 
3139 	VDC_MARK_DRING_ENTRY_FREE(vdc, idx);
3140 
3141 	ldep->is_free = B_TRUE;
3142 	status = dep->payload.status;
3143 	DMSG(vdc, 2, ": is_free = %d : status = %d\n", ldep->is_free, status);
3144 
3145 	/*
3146 	 * If no buffers were used to transfer information to the server when
3147 	 * populating the descriptor then no memory handles need to be unbound
3148 	 * and we can return now.
3149 	 */
3150 	if (ldep->nbytes == 0) {
3151 		cv_signal(&vdc->dring_free_cv);
3152 		return (status);
3153 	}
3154 
3155 	/*
3156 	 * If the upper layer passed in a misaligned address we copied the
3157 	 * data into an aligned buffer before sending it to LDC - we now
3158 	 * copy it back to the original buffer.
3159 	 */
3160 	if (ldep->align_addr) {
3161 		ASSERT(ldep->addr != NULL);
3162 
3163 		if (dep->payload.nbytes > 0)
3164 			bcopy(ldep->align_addr, ldep->addr,
3165 			    dep->payload.nbytes);
3166 		kmem_free(ldep->align_addr,
3167 		    sizeof (caddr_t) * P2ROUNDUP(ldep->nbytes, 8));
3168 		ldep->align_addr = NULL;
3169 	}
3170 
3171 	rv = ldc_mem_unbind_handle(ldep->desc_mhdl);
3172 	if (rv != 0) {
3173 		DMSG(vdc, 0, "?[%d] unbind mhdl 0x%lx @ idx %d failed (%d)",
3174 		    vdc->instance, ldep->desc_mhdl, idx, rv);
3175 		/*
3176 		 * The error returned by the vDisk server is more informative
3177 		 * and thus has a higher priority but if it isn't set we ensure
3178 		 * that this function returns an error.
3179 		 */
3180 		if (status == 0)
3181 			status = EINVAL;
3182 	}
3183 
3184 	cv_signal(&vdc->membind_cv);
3185 	cv_signal(&vdc->dring_free_cv);
3186 
3187 	return (status);
3188 }
3189 
3190 /*
3191  * Function:
3192  *	vdc_populate_mem_hdl()
3193  *
3194  * Description:
3195  *
3196  * Arguments:
3197  *	vdc	- soft state pointer for this instance of the device driver.
3198  *	idx	- Index of the Descriptor Ring entry being modified
3199  *	addr	- virtual address being mapped in
3200  *	nybtes	- number of bytes in 'addr'
3201  *	operation - the vDisk operation being performed (VD_OP_xxx)
3202  *
3203  * Return Code:
3204  *	0	- Success
3205  */
3206 static int
3207 vdc_populate_mem_hdl(vdc_t *vdcp, vdc_local_desc_t *ldep)
3208 {
3209 	vd_dring_entry_t	*dep = NULL;
3210 	ldc_mem_handle_t	mhdl;
3211 	caddr_t			vaddr;
3212 	size_t			nbytes;
3213 	uint8_t			perm = LDC_MEM_RW;
3214 	uint8_t			maptype;
3215 	int			rv = 0;
3216 	int			i;
3217 
3218 	ASSERT(vdcp != NULL);
3219 
3220 	dep = ldep->dep;
3221 	mhdl = ldep->desc_mhdl;
3222 
3223 	switch (ldep->dir) {
3224 	case VIO_read_dir:
3225 		perm = LDC_MEM_W;
3226 		break;
3227 
3228 	case VIO_write_dir:
3229 		perm = LDC_MEM_R;
3230 		break;
3231 
3232 	case VIO_both_dir:
3233 		perm = LDC_MEM_RW;
3234 		break;
3235 
3236 	default:
3237 		ASSERT(0);	/* catch bad programming in vdc */
3238 	}
3239 
3240 	/*
3241 	 * LDC expects any addresses passed in to be 8-byte aligned. We need
3242 	 * to copy the contents of any misaligned buffers to a newly allocated
3243 	 * buffer and bind it instead (and copy the the contents back to the
3244 	 * original buffer passed in when depopulating the descriptor)
3245 	 */
3246 	vaddr = ldep->addr;
3247 	nbytes = ldep->nbytes;
3248 	if (((uint64_t)vaddr & 0x7) != 0) {
3249 		ASSERT(ldep->align_addr == NULL);
3250 		ldep->align_addr =
3251 		    kmem_alloc(sizeof (caddr_t) *
3252 		    P2ROUNDUP(nbytes, 8), KM_SLEEP);
3253 		DMSG(vdcp, 0, "[%d] Misaligned address %p reallocating "
3254 		    "(buf=%p nb=%ld op=%d)\n",
3255 		    vdcp->instance, (void *)vaddr, (void *)ldep->align_addr,
3256 		    nbytes, ldep->operation);
3257 		if (perm != LDC_MEM_W)
3258 			bcopy(vaddr, ldep->align_addr, nbytes);
3259 		vaddr = ldep->align_addr;
3260 	}
3261 
3262 	maptype = LDC_IO_MAP|LDC_SHADOW_MAP|LDC_DIRECT_MAP;
3263 	rv = ldc_mem_bind_handle(mhdl, vaddr, P2ROUNDUP(nbytes, 8),
3264 	    maptype, perm, &dep->payload.cookie[0], &dep->payload.ncookies);
3265 	DMSG(vdcp, 2, "[%d] bound mem handle; ncookies=%d\n",
3266 	    vdcp->instance, dep->payload.ncookies);
3267 	if (rv != 0) {
3268 		DMSG(vdcp, 0, "[%d] Failed to bind LDC memory handle "
3269 		    "(mhdl=%p, buf=%p, err=%d)\n",
3270 		    vdcp->instance, (void *)mhdl, (void *)vaddr, rv);
3271 		if (ldep->align_addr) {
3272 			kmem_free(ldep->align_addr,
3273 			    sizeof (caddr_t) * P2ROUNDUP(nbytes, 8));
3274 			ldep->align_addr = NULL;
3275 		}
3276 		return (EAGAIN);
3277 	}
3278 
3279 	/*
3280 	 * Get the other cookies (if any).
3281 	 */
3282 	for (i = 1; i < dep->payload.ncookies; i++) {
3283 		rv = ldc_mem_nextcookie(mhdl, &dep->payload.cookie[i]);
3284 		if (rv != 0) {
3285 			(void) ldc_mem_unbind_handle(mhdl);
3286 			DMSG(vdcp, 0, "?[%d] Failed to get next cookie "
3287 			    "(mhdl=%lx cnum=%d), err=%d",
3288 			    vdcp->instance, mhdl, i, rv);
3289 			if (ldep->align_addr) {
3290 				kmem_free(ldep->align_addr,
3291 				    sizeof (caddr_t) * ldep->nbytes);
3292 				ldep->align_addr = NULL;
3293 			}
3294 			return (EAGAIN);
3295 		}
3296 	}
3297 
3298 	return (rv);
3299 }
3300 
3301 /*
3302  * Interrupt handlers for messages from LDC
3303  */
3304 
3305 /*
3306  * Function:
3307  *	vdc_handle_cb()
3308  *
3309  * Description:
3310  *
3311  * Arguments:
3312  *	event	- Type of event (LDC_EVT_xxx) that triggered the callback
3313  *	arg	- soft state pointer for this instance of the device driver.
3314  *
3315  * Return Code:
3316  *	0	- Success
3317  */
3318 static uint_t
3319 vdc_handle_cb(uint64_t event, caddr_t arg)
3320 {
3321 	ldc_status_t	ldc_state;
3322 	int		rv = 0;
3323 
3324 	vdc_t	*vdc = (vdc_t *)(void *)arg;
3325 
3326 	ASSERT(vdc != NULL);
3327 
3328 	DMSG(vdc, 1, "evt=%lx seqID=%ld\n", event, vdc->seq_num);
3329 
3330 	/*
3331 	 * Depending on the type of event that triggered this callback,
3332 	 * we modify the handshake state or read the data.
3333 	 *
3334 	 * NOTE: not done as a switch() as event could be triggered by
3335 	 * a state change and a read request. Also the ordering	of the
3336 	 * check for the event types is deliberate.
3337 	 */
3338 	if (event & LDC_EVT_UP) {
3339 		DMSG(vdc, 0, "[%d] Received LDC_EVT_UP\n", vdc->instance);
3340 
3341 		mutex_enter(&vdc->lock);
3342 
3343 		/* get LDC state */
3344 		rv = ldc_status(vdc->ldc_handle, &ldc_state);
3345 		if (rv != 0) {
3346 			DMSG(vdc, 0, "[%d] Couldn't get LDC status %d",
3347 			    vdc->instance, rv);
3348 			return (LDC_SUCCESS);
3349 		}
3350 		if (vdc->ldc_state != LDC_UP && ldc_state == LDC_UP) {
3351 			/*
3352 			 * Reset the transaction sequence numbers when
3353 			 * LDC comes up. We then kick off the handshake
3354 			 * negotiation with the vDisk server.
3355 			 */
3356 			vdc->seq_num = 1;
3357 			vdc->seq_num_reply = 0;
3358 			vdc->ldc_state = ldc_state;
3359 			cv_signal(&vdc->initwait_cv);
3360 		}
3361 
3362 		mutex_exit(&vdc->lock);
3363 	}
3364 
3365 	if (event & LDC_EVT_READ) {
3366 		DMSG(vdc, 1, "[%d] Received LDC_EVT_READ\n", vdc->instance);
3367 		mutex_enter(&vdc->read_lock);
3368 		cv_signal(&vdc->read_cv);
3369 		vdc->read_state = VDC_READ_PENDING;
3370 		mutex_exit(&vdc->read_lock);
3371 
3372 		/* that's all we have to do - no need to handle DOWN/RESET */
3373 		return (LDC_SUCCESS);
3374 	}
3375 
3376 	if (event & (LDC_EVT_RESET|LDC_EVT_DOWN)) {
3377 
3378 		DMSG(vdc, 0, "[%d] Received LDC RESET event\n", vdc->instance);
3379 
3380 		mutex_enter(&vdc->lock);
3381 		/*
3382 		 * Need to wake up any readers so they will
3383 		 * detect that a reset has occurred.
3384 		 */
3385 		mutex_enter(&vdc->read_lock);
3386 		if ((vdc->read_state == VDC_READ_WAITING) ||
3387 		    (vdc->read_state == VDC_READ_RESET))
3388 			cv_signal(&vdc->read_cv);
3389 		vdc->read_state = VDC_READ_RESET;
3390 		mutex_exit(&vdc->read_lock);
3391 
3392 		/* wake up any threads waiting for connection to come up */
3393 		if (vdc->state == VDC_STATE_INIT_WAITING) {
3394 			vdc->state = VDC_STATE_RESETTING;
3395 			cv_signal(&vdc->initwait_cv);
3396 		}
3397 
3398 		mutex_exit(&vdc->lock);
3399 	}
3400 
3401 	if (event & ~(LDC_EVT_UP | LDC_EVT_RESET | LDC_EVT_DOWN | LDC_EVT_READ))
3402 		DMSG(vdc, 0, "![%d] Unexpected LDC event (%lx) received",
3403 		    vdc->instance, event);
3404 
3405 	return (LDC_SUCCESS);
3406 }
3407 
3408 /*
3409  * Function:
3410  *	vdc_wait_for_response()
3411  *
3412  * Description:
3413  *	Block waiting for a response from the server. If there is
3414  *	no data the thread block on the read_cv that is signalled
3415  *	by the callback when an EVT_READ occurs.
3416  *
3417  * Arguments:
3418  *	vdcp	- soft state pointer for this instance of the device driver.
3419  *
3420  * Return Code:
3421  *	0	- Success
3422  */
3423 static int
3424 vdc_wait_for_response(vdc_t *vdcp, vio_msg_t *msgp)
3425 {
3426 	size_t		nbytes = sizeof (*msgp);
3427 	int		status;
3428 
3429 	ASSERT(vdcp != NULL);
3430 
3431 	DMSG(vdcp, 1, "[%d] Entered\n", vdcp->instance);
3432 
3433 	status = vdc_recv(vdcp, msgp, &nbytes);
3434 	DMSG(vdcp, 3, "vdc_read() done.. status=0x%x size=0x%x\n",
3435 	    status, (int)nbytes);
3436 	if (status) {
3437 		DMSG(vdcp, 0, "?[%d] Error %d reading LDC msg\n",
3438 		    vdcp->instance, status);
3439 		return (status);
3440 	}
3441 
3442 	if (nbytes < sizeof (vio_msg_tag_t)) {
3443 		DMSG(vdcp, 0, "?[%d] Expect %lu bytes; recv'd %lu\n",
3444 		    vdcp->instance, sizeof (vio_msg_tag_t), nbytes);
3445 		return (ENOMSG);
3446 	}
3447 
3448 	DMSG(vdcp, 2, "[%d] (%x/%x/%x)\n", vdcp->instance,
3449 	    msgp->tag.vio_msgtype,
3450 	    msgp->tag.vio_subtype,
3451 	    msgp->tag.vio_subtype_env);
3452 
3453 	/*
3454 	 * Verify the Session ID of the message
3455 	 *
3456 	 * Every message after the Version has been negotiated should
3457 	 * have the correct session ID set.
3458 	 */
3459 	if ((msgp->tag.vio_sid != vdcp->session_id) &&
3460 	    (msgp->tag.vio_subtype_env != VIO_VER_INFO)) {
3461 		DMSG(vdcp, 0, "[%d] Invalid SID: received 0x%x, "
3462 		    "expected 0x%lx [seq num %lx @ %d]",
3463 		    vdcp->instance, msgp->tag.vio_sid,
3464 		    vdcp->session_id,
3465 		    ((vio_dring_msg_t *)msgp)->seq_num,
3466 		    ((vio_dring_msg_t *)msgp)->start_idx);
3467 		return (ENOMSG);
3468 	}
3469 	return (0);
3470 }
3471 
3472 
3473 /*
3474  * Function:
3475  *	vdc_resubmit_backup_dring()
3476  *
3477  * Description:
3478  *	Resubmit each descriptor in the backed up dring to
3479  * 	vDisk server. The Dring was backed up during connection
3480  *	reset.
3481  *
3482  * Arguments:
3483  *	vdcp	- soft state pointer for this instance of the device driver.
3484  *
3485  * Return Code:
3486  *	0	- Success
3487  */
3488 static int
3489 vdc_resubmit_backup_dring(vdc_t *vdcp)
3490 {
3491 	int		count;
3492 	int		b_idx;
3493 	int		rv;
3494 	int		dring_size;
3495 	int		status;
3496 	vio_msg_t	vio_msg;
3497 	vdc_local_desc_t	*curr_ldep;
3498 
3499 	ASSERT(MUTEX_NOT_HELD(&vdcp->lock));
3500 	ASSERT(vdcp->state == VDC_STATE_HANDLE_PENDING);
3501 
3502 	if (vdcp->local_dring_backup == NULL) {
3503 		/* the pending requests have already been processed */
3504 		return (0);
3505 	}
3506 
3507 	DMSG(vdcp, 1, "restoring pending dring entries (len=%d, tail=%d)\n",
3508 	    vdcp->local_dring_backup_len, vdcp->local_dring_backup_tail);
3509 
3510 	/*
3511 	 * Walk the backup copy of the local descriptor ring and
3512 	 * resubmit all the outstanding transactions.
3513 	 */
3514 	b_idx = vdcp->local_dring_backup_tail;
3515 	for (count = 0; count < vdcp->local_dring_backup_len; count++) {
3516 
3517 		curr_ldep = &(vdcp->local_dring_backup[b_idx]);
3518 
3519 		/* only resubmit outstanding transactions */
3520 		if (!curr_ldep->is_free) {
3521 
3522 			DMSG(vdcp, 1, "resubmitting entry idx=%x\n", b_idx);
3523 			mutex_enter(&vdcp->lock);
3524 			rv = vdc_populate_descriptor(vdcp, curr_ldep->operation,
3525 			    curr_ldep->addr, curr_ldep->nbytes,
3526 			    curr_ldep->slice, curr_ldep->offset,
3527 			    curr_ldep->cb_type, curr_ldep->cb_arg,
3528 			    curr_ldep->dir);
3529 			mutex_exit(&vdcp->lock);
3530 			if (rv) {
3531 				DMSG(vdcp, 1, "[%d] cannot resubmit entry %d\n",
3532 				    vdcp->instance, b_idx);
3533 				return (rv);
3534 			}
3535 
3536 			/* Wait for the response message. */
3537 			DMSG(vdcp, 1, "waiting for response to idx=%x\n",
3538 			    b_idx);
3539 			status = vdc_wait_for_response(vdcp, &vio_msg);
3540 			if (status) {
3541 				DMSG(vdcp, 1, "[%d] wait_for_response "
3542 				    "returned err=%d\n", vdcp->instance,
3543 				    status);
3544 				return (status);
3545 			}
3546 
3547 			DMSG(vdcp, 1, "processing msg for idx=%x\n", b_idx);
3548 			status = vdc_process_data_msg(vdcp, &vio_msg);
3549 			if (status) {
3550 				DMSG(vdcp, 1, "[%d] process_data_msg "
3551 				    "returned err=%d\n", vdcp->instance,
3552 				    status);
3553 				return (status);
3554 			}
3555 		}
3556 
3557 		/* get the next element to submit */
3558 		if (++b_idx >= vdcp->local_dring_backup_len)
3559 			b_idx = 0;
3560 	}
3561 
3562 	/* all done - now clear up pending dring copy */
3563 	dring_size = vdcp->local_dring_backup_len *
3564 	    sizeof (vdcp->local_dring_backup[0]);
3565 
3566 	(void) kmem_free(vdcp->local_dring_backup, dring_size);
3567 
3568 	vdcp->local_dring_backup = NULL;
3569 
3570 	return (0);
3571 }
3572 
3573 /*
3574  * Function:
3575  *	vdc_cancel_backup_dring
3576  *
3577  * Description:
3578  *	Cancel each descriptor in the backed up dring to vDisk server.
3579  *	The Dring was backed up during connection reset.
3580  *
3581  * Arguments:
3582  *	vdcp	- soft state pointer for this instance of the device driver.
3583  *
3584  * Return Code:
3585  *	None
3586  */
3587 void
3588 vdc_cancel_backup_ring(vdc_t *vdcp)
3589 {
3590 	vdc_local_desc_t *ldep;
3591 	struct buf 	*bufp;
3592 	int		count;
3593 	int		b_idx;
3594 	int		dring_size;
3595 
3596 	ASSERT(MUTEX_HELD(&vdcp->lock));
3597 	ASSERT(vdcp->state == VDC_STATE_INIT ||
3598 	    vdcp->state == VDC_STATE_INIT_WAITING ||
3599 	    vdcp->state == VDC_STATE_NEGOTIATE ||
3600 	    vdcp->state == VDC_STATE_RESETTING);
3601 
3602 	if (vdcp->local_dring_backup == NULL) {
3603 		/* the pending requests have already been processed */
3604 		return;
3605 	}
3606 
3607 	DMSG(vdcp, 1, "cancelling pending dring entries (len=%d, tail=%d)\n",
3608 	    vdcp->local_dring_backup_len, vdcp->local_dring_backup_tail);
3609 
3610 	/*
3611 	 * Walk the backup copy of the local descriptor ring and
3612 	 * cancel all the outstanding transactions.
3613 	 */
3614 	b_idx = vdcp->local_dring_backup_tail;
3615 	for (count = 0; count < vdcp->local_dring_backup_len; count++) {
3616 
3617 		ldep = &(vdcp->local_dring_backup[b_idx]);
3618 
3619 		/* only cancel outstanding transactions */
3620 		if (!ldep->is_free) {
3621 
3622 			DMSG(vdcp, 1, "cancelling entry idx=%x\n", b_idx);
3623 
3624 			/*
3625 			 * All requests have already been cleared from the
3626 			 * local descriptor ring and the LDC channel has been
3627 			 * reset so we will never get any reply for these
3628 			 * requests. Now we just have to notify threads waiting
3629 			 * for replies that the request has failed.
3630 			 */
3631 			switch (ldep->cb_type) {
3632 			case CB_SYNC:
3633 				ASSERT(vdcp->sync_op_pending);
3634 				vdcp->sync_op_status = EIO;
3635 				vdcp->sync_op_pending = B_FALSE;
3636 				cv_signal(&vdcp->sync_pending_cv);
3637 				break;
3638 
3639 			case CB_STRATEGY:
3640 				bufp = ldep->cb_arg;
3641 				ASSERT(bufp != NULL);
3642 				bufp->b_resid = bufp->b_bcount;
3643 				bioerror(bufp, EIO);
3644 				biodone(bufp);
3645 				break;
3646 
3647 			default:
3648 				ASSERT(0);
3649 			}
3650 
3651 		}
3652 
3653 		/* get the next element to cancel */
3654 		if (++b_idx >= vdcp->local_dring_backup_len)
3655 			b_idx = 0;
3656 	}
3657 
3658 	/* all done - now clear up pending dring copy */
3659 	dring_size = vdcp->local_dring_backup_len *
3660 	    sizeof (vdcp->local_dring_backup[0]);
3661 
3662 	(void) kmem_free(vdcp->local_dring_backup, dring_size);
3663 
3664 	vdcp->local_dring_backup = NULL;
3665 
3666 	DTRACE_IO2(processed, int, count, vdc_t *, vdcp);
3667 }
3668 
3669 /*
3670  * Function:
3671  *	vdc_connection_timeout
3672  *
3673  * Description:
3674  *	This function is invoked if the timeout set to establish the connection
3675  *	with vds expires. This will happen if we spend too much time in the
3676  *	VDC_STATE_INIT_WAITING or VDC_STATE_NEGOTIATE states. Then we will
3677  *	cancel any pending request and mark them as failed.
3678  *
3679  *	If the timeout does not expire, it will be cancelled when we reach the
3680  *	VDC_STATE_HANDLE_PENDING or VDC_STATE_RESETTING state. This function can
3681  *	be invoked while we are in the VDC_STATE_HANDLE_PENDING or
3682  *	VDC_STATE_RESETTING state in which case we do nothing because the
3683  *	timeout is being cancelled.
3684  *
3685  * Arguments:
3686  *	arg	- argument of the timeout function actually a soft state
3687  *		  pointer for the instance of the device driver.
3688  *
3689  * Return Code:
3690  *	None
3691  */
3692 void
3693 vdc_connection_timeout(void *arg)
3694 {
3695 	vdc_t 		*vdcp = (vdc_t *)arg;
3696 
3697 	mutex_enter(&vdcp->lock);
3698 
3699 	if (vdcp->state == VDC_STATE_HANDLE_PENDING ||
3700 	    vdcp->state == VDC_STATE_DETACH) {
3701 		/*
3702 		 * The connection has just been re-established or
3703 		 * we are detaching.
3704 		 */
3705 		vdcp->ctimeout_reached = B_FALSE;
3706 		mutex_exit(&vdcp->lock);
3707 		return;
3708 	}
3709 
3710 	vdcp->ctimeout_reached = B_TRUE;
3711 
3712 	/* notify requests waiting for sending */
3713 	cv_broadcast(&vdcp->running_cv);
3714 
3715 	/* cancel requests waiting for a result */
3716 	vdc_cancel_backup_ring(vdcp);
3717 
3718 	mutex_exit(&vdcp->lock);
3719 
3720 	cmn_err(CE_NOTE, "[%d] connection to service domain timeout",
3721 	    vdcp->instance);
3722 }
3723 
3724 /*
3725  * Function:
3726  *	vdc_backup_local_dring()
3727  *
3728  * Description:
3729  *	Backup the current dring in the event of a reset. The Dring
3730  *	transactions will be resubmitted to the server when the
3731  *	connection is restored.
3732  *
3733  * Arguments:
3734  *	vdcp	- soft state pointer for this instance of the device driver.
3735  *
3736  * Return Code:
3737  *	NONE
3738  */
3739 static void
3740 vdc_backup_local_dring(vdc_t *vdcp)
3741 {
3742 	int dring_size;
3743 
3744 	ASSERT(MUTEX_HELD(&vdcp->lock));
3745 	ASSERT(vdcp->state == VDC_STATE_RESETTING);
3746 
3747 	/*
3748 	 * If the backup dring is stil around, it means
3749 	 * that the last restore did not complete. However,
3750 	 * since we never got back into the running state,
3751 	 * the backup copy we have is still valid.
3752 	 */
3753 	if (vdcp->local_dring_backup != NULL) {
3754 		DMSG(vdcp, 1, "reusing local descriptor ring backup "
3755 		    "(len=%d, tail=%d)\n", vdcp->local_dring_backup_len,
3756 		    vdcp->local_dring_backup_tail);
3757 		return;
3758 	}
3759 
3760 	/*
3761 	 * The backup dring can be NULL and the local dring may not be
3762 	 * initialized. This can happen if we had a reset while establishing
3763 	 * a new connection but after the connection has timed out. In that
3764 	 * case the backup dring is NULL because the requests have been
3765 	 * cancelled and the request occured before the local dring is
3766 	 * initialized.
3767 	 */
3768 	if (!(vdcp->initialized & VDC_DRING_LOCAL))
3769 		return;
3770 
3771 	DMSG(vdcp, 1, "backing up the local descriptor ring (len=%d, "
3772 	    "tail=%d)\n", vdcp->dring_len, vdcp->dring_curr_idx);
3773 
3774 	dring_size = vdcp->dring_len * sizeof (vdcp->local_dring[0]);
3775 
3776 	vdcp->local_dring_backup = kmem_alloc(dring_size, KM_SLEEP);
3777 	bcopy(vdcp->local_dring, vdcp->local_dring_backup, dring_size);
3778 
3779 	vdcp->local_dring_backup_tail = vdcp->dring_curr_idx;
3780 	vdcp->local_dring_backup_len = vdcp->dring_len;
3781 }
3782 
3783 /* -------------------------------------------------------------------------- */
3784 
3785 /*
3786  * The following functions process the incoming messages from vds
3787  */
3788 
3789 /*
3790  * Function:
3791  *      vdc_process_msg_thread()
3792  *
3793  * Description:
3794  *
3795  *	Main VDC message processing thread. Each vDisk instance
3796  * 	consists of a copy of this thread. This thread triggers
3797  * 	all the handshakes and data exchange with the server. It
3798  * 	also handles all channel resets
3799  *
3800  * Arguments:
3801  *      vdc     - soft state pointer for this instance of the device driver.
3802  *
3803  * Return Code:
3804  *      None
3805  */
3806 static void
3807 vdc_process_msg_thread(vdc_t *vdcp)
3808 {
3809 	int	status;
3810 	int	ctimeout;
3811 	timeout_id_t tmid = 0;
3812 
3813 	mutex_enter(&vdcp->lock);
3814 
3815 	for (;;) {
3816 
3817 #define	Q(_s)	(vdcp->state == _s) ? #_s :
3818 		DMSG(vdcp, 3, "state = %d (%s)\n", vdcp->state,
3819 		    Q(VDC_STATE_INIT)
3820 		    Q(VDC_STATE_INIT_WAITING)
3821 		    Q(VDC_STATE_NEGOTIATE)
3822 		    Q(VDC_STATE_HANDLE_PENDING)
3823 		    Q(VDC_STATE_RUNNING)
3824 		    Q(VDC_STATE_RESETTING)
3825 		    Q(VDC_STATE_DETACH)
3826 		    "UNKNOWN");
3827 
3828 		switch (vdcp->state) {
3829 		case VDC_STATE_INIT:
3830 
3831 			/*
3832 			 * If requested, start a timeout to check if the
3833 			 * connection with vds is established in the
3834 			 * specified delay. If the timeout expires, we
3835 			 * will cancel any pending request.
3836 			 *
3837 			 * If some reset have occurred while establishing
3838 			 * the connection, we already have a timeout armed
3839 			 * and in that case we don't need to arm a new one.
3840 			 */
3841 			ctimeout = (vdc_timeout != 0)?
3842 			    vdc_timeout : vdcp->ctimeout;
3843 
3844 			if (ctimeout != 0 && tmid == 0) {
3845 				tmid = timeout(vdc_connection_timeout, vdcp,
3846 				    ctimeout * drv_usectohz(1000000));
3847 			}
3848 
3849 			/* Check if have re-initializing repeatedly */
3850 			if (vdcp->hshake_cnt++ > vdc_hshake_retries &&
3851 			    vdcp->lifecycle != VDC_LC_ONLINE) {
3852 				cmn_err(CE_NOTE, "[%d] disk access failed.\n",
3853 				    vdcp->instance);
3854 				vdcp->state = VDC_STATE_DETACH;
3855 				break;
3856 			}
3857 
3858 			/* Bring up connection with vds via LDC */
3859 			status = vdc_start_ldc_connection(vdcp);
3860 			if (status == EINVAL) {
3861 				DMSG(vdcp, 0, "[%d] Could not start LDC",
3862 				    vdcp->instance);
3863 				vdcp->state = VDC_STATE_DETACH;
3864 			} else {
3865 				vdcp->state = VDC_STATE_INIT_WAITING;
3866 			}
3867 			break;
3868 
3869 		case VDC_STATE_INIT_WAITING:
3870 
3871 			/*
3872 			 * Let the callback event move us on
3873 			 * when channel is open to server
3874 			 */
3875 			while (vdcp->ldc_state != LDC_UP) {
3876 				cv_wait(&vdcp->initwait_cv, &vdcp->lock);
3877 				if (vdcp->state != VDC_STATE_INIT_WAITING) {
3878 					DMSG(vdcp, 0,
3879 				"state moved to %d out from under us...\n",
3880 					    vdcp->state);
3881 
3882 					break;
3883 				}
3884 			}
3885 			if (vdcp->state == VDC_STATE_INIT_WAITING &&
3886 			    vdcp->ldc_state == LDC_UP) {
3887 				vdcp->state = VDC_STATE_NEGOTIATE;
3888 			}
3889 			break;
3890 
3891 		case VDC_STATE_NEGOTIATE:
3892 			switch (status = vdc_ver_negotiation(vdcp)) {
3893 			case 0:
3894 				break;
3895 			default:
3896 				DMSG(vdcp, 0, "ver negotiate failed (%d)..\n",
3897 				    status);
3898 				goto reset;
3899 			}
3900 
3901 			switch (status = vdc_attr_negotiation(vdcp)) {
3902 			case 0:
3903 				break;
3904 			default:
3905 				DMSG(vdcp, 0, "attr negotiate failed (%d)..\n",
3906 				    status);
3907 				goto reset;
3908 			}
3909 
3910 			switch (status = vdc_dring_negotiation(vdcp)) {
3911 			case 0:
3912 				break;
3913 			default:
3914 				DMSG(vdcp, 0, "dring negotiate failed (%d)..\n",
3915 				    status);
3916 				goto reset;
3917 			}
3918 
3919 			switch (status = vdc_rdx_exchange(vdcp)) {
3920 			case 0:
3921 				vdcp->state = VDC_STATE_HANDLE_PENDING;
3922 				goto done;
3923 			default:
3924 				DMSG(vdcp, 0, "RDX xchg failed ..(%d)\n",
3925 				    status);
3926 				goto reset;
3927 			}
3928 reset:
3929 			DMSG(vdcp, 0, "negotiation failed: resetting (%d)\n",
3930 			    status);
3931 			vdcp->state = VDC_STATE_RESETTING;
3932 			vdcp->self_reset = B_TRUE;
3933 done:
3934 			DMSG(vdcp, 0, "negotiation complete (state=0x%x)...\n",
3935 			    vdcp->state);
3936 			break;
3937 
3938 		case VDC_STATE_HANDLE_PENDING:
3939 
3940 			if (vdcp->ctimeout_reached) {
3941 				/*
3942 				 * The connection timeout had been reached so
3943 				 * pending requests have been cancelled. Now
3944 				 * that the connection is back we can reset
3945 				 * the timeout.
3946 				 */
3947 				ASSERT(vdcp->local_dring_backup == NULL);
3948 				ASSERT(tmid != 0);
3949 				tmid = 0;
3950 				vdcp->ctimeout_reached = B_FALSE;
3951 				vdcp->state = VDC_STATE_RUNNING;
3952 				DMSG(vdcp, 0, "[%d] connection to service "
3953 				    "domain is up", vdcp->instance);
3954 				break;
3955 			}
3956 
3957 			mutex_exit(&vdcp->lock);
3958 			if (tmid != 0) {
3959 				(void) untimeout(tmid);
3960 				tmid = 0;
3961 			}
3962 			status = vdc_resubmit_backup_dring(vdcp);
3963 			mutex_enter(&vdcp->lock);
3964 
3965 			if (status)
3966 				vdcp->state = VDC_STATE_RESETTING;
3967 			else
3968 				vdcp->state = VDC_STATE_RUNNING;
3969 
3970 			break;
3971 
3972 		/* enter running state */
3973 		case VDC_STATE_RUNNING:
3974 			/*
3975 			 * Signal anyone waiting for the connection
3976 			 * to come on line.
3977 			 */
3978 			vdcp->hshake_cnt = 0;
3979 			cv_broadcast(&vdcp->running_cv);
3980 
3981 			/* failfast has to been checked after reset */
3982 			cv_signal(&vdcp->failfast_cv);
3983 
3984 			/* ownership is lost during reset */
3985 			if (vdcp->ownership & VDC_OWNERSHIP_WANTED)
3986 				vdcp->ownership |= VDC_OWNERSHIP_RESET;
3987 			cv_signal(&vdcp->ownership_cv);
3988 
3989 			mutex_exit(&vdcp->lock);
3990 
3991 			for (;;) {
3992 				vio_msg_t msg;
3993 				status = vdc_wait_for_response(vdcp, &msg);
3994 				if (status) break;
3995 
3996 				DMSG(vdcp, 1, "[%d] new pkt(s) available\n",
3997 				    vdcp->instance);
3998 				status = vdc_process_data_msg(vdcp, &msg);
3999 				if (status) {
4000 					DMSG(vdcp, 1, "[%d] process_data_msg "
4001 					    "returned err=%d\n", vdcp->instance,
4002 					    status);
4003 					break;
4004 				}
4005 
4006 			}
4007 
4008 			mutex_enter(&vdcp->lock);
4009 
4010 			vdcp->state = VDC_STATE_RESETTING;
4011 			vdcp->self_reset = B_TRUE;
4012 			break;
4013 
4014 		case VDC_STATE_RESETTING:
4015 			/*
4016 			 * When we reach this state, we either come from the
4017 			 * VDC_STATE_RUNNING state and we can have pending
4018 			 * request but no timeout is armed; or we come from
4019 			 * the VDC_STATE_INIT_WAITING, VDC_NEGOTIATE or
4020 			 * VDC_HANDLE_PENDING state and there is no pending
4021 			 * request or pending requests have already been copied
4022 			 * into the backup dring. So we can safely keep the
4023 			 * connection timeout armed while we are in this state.
4024 			 */
4025 
4026 			DMSG(vdcp, 0, "Initiating channel reset "
4027 			    "(pending = %d)\n", (int)vdcp->threads_pending);
4028 
4029 			if (vdcp->self_reset) {
4030 				DMSG(vdcp, 0,
4031 				    "[%d] calling stop_ldc_connection.\n",
4032 				    vdcp->instance);
4033 				status = vdc_stop_ldc_connection(vdcp);
4034 				vdcp->self_reset = B_FALSE;
4035 			}
4036 
4037 			/*
4038 			 * Wait for all threads currently waiting
4039 			 * for a free dring entry to use.
4040 			 */
4041 			while (vdcp->threads_pending) {
4042 				cv_broadcast(&vdcp->membind_cv);
4043 				cv_broadcast(&vdcp->dring_free_cv);
4044 				mutex_exit(&vdcp->lock);
4045 				/* give the waiters enough time to wake up */
4046 				delay(vdc_hz_min_ldc_delay);
4047 				mutex_enter(&vdcp->lock);
4048 			}
4049 
4050 			ASSERT(vdcp->threads_pending == 0);
4051 
4052 			/* Sanity check that no thread is receiving */
4053 			ASSERT(vdcp->read_state != VDC_READ_WAITING);
4054 
4055 			vdcp->read_state = VDC_READ_IDLE;
4056 
4057 			vdc_backup_local_dring(vdcp);
4058 
4059 			/* cleanup the old d-ring */
4060 			vdc_destroy_descriptor_ring(vdcp);
4061 
4062 			/* go and start again */
4063 			vdcp->state = VDC_STATE_INIT;
4064 
4065 			break;
4066 
4067 		case VDC_STATE_DETACH:
4068 			DMSG(vdcp, 0, "[%d] Reset thread exit cleanup ..\n",
4069 			    vdcp->instance);
4070 
4071 			/* cancel any pending timeout */
4072 			mutex_exit(&vdcp->lock);
4073 			if (tmid != 0) {
4074 				(void) untimeout(tmid);
4075 				tmid = 0;
4076 			}
4077 			mutex_enter(&vdcp->lock);
4078 
4079 			/*
4080 			 * Signal anyone waiting for connection
4081 			 * to come online
4082 			 */
4083 			cv_broadcast(&vdcp->running_cv);
4084 
4085 			while (vdcp->sync_op_pending) {
4086 				cv_signal(&vdcp->sync_pending_cv);
4087 				cv_signal(&vdcp->sync_blocked_cv);
4088 				mutex_exit(&vdcp->lock);
4089 				/* give the waiters enough time to wake up */
4090 				delay(vdc_hz_min_ldc_delay);
4091 				mutex_enter(&vdcp->lock);
4092 			}
4093 
4094 			mutex_exit(&vdcp->lock);
4095 
4096 			DMSG(vdcp, 0, "[%d] Msg processing thread exiting ..\n",
4097 			    vdcp->instance);
4098 			thread_exit();
4099 			break;
4100 		}
4101 	}
4102 }
4103 
4104 
4105 /*
4106  * Function:
4107  *	vdc_process_data_msg()
4108  *
4109  * Description:
4110  *	This function is called by the message processing thread each time
4111  *	a message with a msgtype of VIO_TYPE_DATA is received. It will either
4112  *	be an ACK or NACK from vds[1] which vdc handles as follows.
4113  *		ACK	- wake up the waiting thread
4114  *		NACK	- resend any messages necessary
4115  *
4116  *	[1] Although the message format allows it, vds should not send a
4117  *	    VIO_SUBTYPE_INFO message to vdc asking it to read data; if for
4118  *	    some bizarre reason it does, vdc will reset the connection.
4119  *
4120  * Arguments:
4121  *	vdc	- soft state pointer for this instance of the device driver.
4122  *	msg	- the LDC message sent by vds
4123  *
4124  * Return Code:
4125  *	0	- Success.
4126  *	> 0	- error value returned by LDC
4127  */
4128 static int
4129 vdc_process_data_msg(vdc_t *vdcp, vio_msg_t *msg)
4130 {
4131 	int			status = 0;
4132 	vio_dring_msg_t		*dring_msg;
4133 	vdc_local_desc_t	*ldep = NULL;
4134 	int			start, end;
4135 	int			idx;
4136 
4137 	dring_msg = (vio_dring_msg_t *)msg;
4138 
4139 	ASSERT(msg->tag.vio_msgtype == VIO_TYPE_DATA);
4140 	ASSERT(vdcp != NULL);
4141 
4142 	mutex_enter(&vdcp->lock);
4143 
4144 	/*
4145 	 * Check to see if the message has bogus data
4146 	 */
4147 	idx = start = dring_msg->start_idx;
4148 	end = dring_msg->end_idx;
4149 	if ((start >= vdcp->dring_len) ||
4150 	    (end >= vdcp->dring_len) || (end < -1)) {
4151 		DMSG(vdcp, 0, "[%d] Bogus ACK data : start %d, end %d\n",
4152 		    vdcp->instance, start, end);
4153 		mutex_exit(&vdcp->lock);
4154 		return (EINVAL);
4155 	}
4156 
4157 	/*
4158 	 * Verify that the sequence number is what vdc expects.
4159 	 */
4160 	switch (vdc_verify_seq_num(vdcp, dring_msg)) {
4161 	case VDC_SEQ_NUM_TODO:
4162 		break;	/* keep processing this message */
4163 	case VDC_SEQ_NUM_SKIP:
4164 		mutex_exit(&vdcp->lock);
4165 		return (0);
4166 	case VDC_SEQ_NUM_INVALID:
4167 		mutex_exit(&vdcp->lock);
4168 		DMSG(vdcp, 0, "[%d] invalid seqno\n", vdcp->instance);
4169 		return (ENXIO);
4170 	}
4171 
4172 	if (msg->tag.vio_subtype == VIO_SUBTYPE_NACK) {
4173 		DMSG(vdcp, 0, "[%d] DATA NACK\n", vdcp->instance);
4174 		VDC_DUMP_DRING_MSG(dring_msg);
4175 		mutex_exit(&vdcp->lock);
4176 		return (EIO);
4177 
4178 	} else if (msg->tag.vio_subtype == VIO_SUBTYPE_INFO) {
4179 		mutex_exit(&vdcp->lock);
4180 		return (EPROTO);
4181 	}
4182 
4183 	DTRACE_IO2(recv, vio_dring_msg_t, dring_msg, vdc_t *, vdcp);
4184 	DMSG(vdcp, 1, ": start %d end %d\n", start, end);
4185 	ASSERT(start == end);
4186 
4187 	ldep = &vdcp->local_dring[idx];
4188 
4189 	DMSG(vdcp, 1, ": state 0x%x - cb_type 0x%x\n",
4190 	    ldep->dep->hdr.dstate, ldep->cb_type);
4191 
4192 	if (ldep->dep->hdr.dstate == VIO_DESC_DONE) {
4193 		struct buf *bufp;
4194 
4195 		switch (ldep->cb_type) {
4196 		case CB_SYNC:
4197 			ASSERT(vdcp->sync_op_pending);
4198 
4199 			status = vdc_depopulate_descriptor(vdcp, idx);
4200 			vdcp->sync_op_status = status;
4201 			vdcp->sync_op_pending = B_FALSE;
4202 			cv_signal(&vdcp->sync_pending_cv);
4203 			break;
4204 
4205 		case CB_STRATEGY:
4206 			bufp = ldep->cb_arg;
4207 			ASSERT(bufp != NULL);
4208 			bufp->b_resid =
4209 			    bufp->b_bcount - ldep->dep->payload.nbytes;
4210 			status = ldep->dep->payload.status; /* Future:ntoh */
4211 			if (status != 0) {
4212 				DMSG(vdcp, 1, "strategy status=%d\n", status);
4213 				bioerror(bufp, status);
4214 			}
4215 
4216 			(void) vdc_depopulate_descriptor(vdcp, idx);
4217 
4218 			DMSG(vdcp, 1,
4219 			    "strategy complete req=%ld bytes resp=%ld bytes\n",
4220 			    bufp->b_bcount, ldep->dep->payload.nbytes);
4221 
4222 			if (status != 0 && vdcp->failfast_interval != 0) {
4223 				/*
4224 				 * The I/O has failed and failfast is enabled.
4225 				 * We need the failfast thread to check if the
4226 				 * failure is due to a reservation conflict.
4227 				 */
4228 				(void) vdc_failfast_io_queue(vdcp, bufp);
4229 			} else {
4230 				biodone(bufp);
4231 			}
4232 			break;
4233 
4234 		default:
4235 			ASSERT(0);
4236 		}
4237 	}
4238 
4239 	/* let the arrival signal propogate */
4240 	mutex_exit(&vdcp->lock);
4241 
4242 	/* probe gives the count of how many entries were processed */
4243 	DTRACE_IO2(processed, int, 1, vdc_t *, vdcp);
4244 
4245 	return (0);
4246 }
4247 
4248 
4249 /*
4250  * Function:
4251  *	vdc_handle_ver_msg()
4252  *
4253  * Description:
4254  *
4255  * Arguments:
4256  *	vdc	- soft state pointer for this instance of the device driver.
4257  *	ver_msg	- LDC message sent by vDisk server
4258  *
4259  * Return Code:
4260  *	0	- Success
4261  */
4262 static int
4263 vdc_handle_ver_msg(vdc_t *vdc, vio_ver_msg_t *ver_msg)
4264 {
4265 	int status = 0;
4266 
4267 	ASSERT(vdc != NULL);
4268 	ASSERT(mutex_owned(&vdc->lock));
4269 
4270 	if (ver_msg->tag.vio_subtype_env != VIO_VER_INFO) {
4271 		return (EPROTO);
4272 	}
4273 
4274 	if (ver_msg->dev_class != VDEV_DISK_SERVER) {
4275 		return (EINVAL);
4276 	}
4277 
4278 	switch (ver_msg->tag.vio_subtype) {
4279 	case VIO_SUBTYPE_ACK:
4280 		/*
4281 		 * We check to see if the version returned is indeed supported
4282 		 * (The server may have also adjusted the minor number downwards
4283 		 * and if so 'ver_msg' will contain the actual version agreed)
4284 		 */
4285 		if (vdc_is_supported_version(ver_msg)) {
4286 			vdc->ver.major = ver_msg->ver_major;
4287 			vdc->ver.minor = ver_msg->ver_minor;
4288 			ASSERT(vdc->ver.major > 0);
4289 		} else {
4290 			status = EPROTO;
4291 		}
4292 		break;
4293 
4294 	case VIO_SUBTYPE_NACK:
4295 		/*
4296 		 * call vdc_is_supported_version() which will return the next
4297 		 * supported version (if any) in 'ver_msg'
4298 		 */
4299 		(void) vdc_is_supported_version(ver_msg);
4300 		if (ver_msg->ver_major > 0) {
4301 			size_t len = sizeof (*ver_msg);
4302 
4303 			ASSERT(vdc->ver.major > 0);
4304 
4305 			/* reset the necessary fields and resend */
4306 			ver_msg->tag.vio_subtype = VIO_SUBTYPE_INFO;
4307 			ver_msg->dev_class = VDEV_DISK;
4308 
4309 			status = vdc_send(vdc, (caddr_t)ver_msg, &len);
4310 			DMSG(vdc, 0, "[%d] Resend VER info (LDC status = %d)\n",
4311 			    vdc->instance, status);
4312 			if (len != sizeof (*ver_msg))
4313 				status = EBADMSG;
4314 		} else {
4315 			DMSG(vdc, 0, "[%d] No common version with vDisk server",
4316 			    vdc->instance);
4317 			status = ENOTSUP;
4318 		}
4319 
4320 		break;
4321 	case VIO_SUBTYPE_INFO:
4322 		/*
4323 		 * Handle the case where vds starts handshake
4324 		 * (for now only vdc is the instigator)
4325 		 */
4326 		status = ENOTSUP;
4327 		break;
4328 
4329 	default:
4330 		status = EINVAL;
4331 		break;
4332 	}
4333 
4334 	return (status);
4335 }
4336 
4337 /*
4338  * Function:
4339  *	vdc_handle_attr_msg()
4340  *
4341  * Description:
4342  *
4343  * Arguments:
4344  *	vdc	- soft state pointer for this instance of the device driver.
4345  *	attr_msg	- LDC message sent by vDisk server
4346  *
4347  * Return Code:
4348  *	0	- Success
4349  */
4350 static int
4351 vdc_handle_attr_msg(vdc_t *vdc, vd_attr_msg_t *attr_msg)
4352 {
4353 	int status = 0;
4354 
4355 	ASSERT(vdc != NULL);
4356 	ASSERT(mutex_owned(&vdc->lock));
4357 
4358 	if (attr_msg->tag.vio_subtype_env != VIO_ATTR_INFO) {
4359 		return (EPROTO);
4360 	}
4361 
4362 	switch (attr_msg->tag.vio_subtype) {
4363 	case VIO_SUBTYPE_ACK:
4364 		/*
4365 		 * We now verify the attributes sent by vds.
4366 		 */
4367 		if (attr_msg->vdisk_size == 0) {
4368 			DMSG(vdc, 0, "[%d] Invalid disk size from vds",
4369 			    vdc->instance);
4370 			status = EINVAL;
4371 			break;
4372 		}
4373 
4374 		if (attr_msg->max_xfer_sz == 0) {
4375 			DMSG(vdc, 0, "[%d] Invalid transfer size from vds",
4376 			    vdc->instance);
4377 			status = EINVAL;
4378 			break;
4379 		}
4380 
4381 		if (attr_msg->vdisk_size == VD_SIZE_UNKNOWN) {
4382 			DMSG(vdc, 0, "[%d] Unknown disk size from vds",
4383 			    vdc->instance);
4384 			attr_msg->vdisk_size = 0;
4385 		}
4386 
4387 		/*
4388 		 * If the disk size is already set check that it hasn't changed.
4389 		 */
4390 		if ((vdc->vdisk_size != 0) && (attr_msg->vdisk_size != 0) &&
4391 		    (vdc->vdisk_size != attr_msg->vdisk_size)) {
4392 			DMSG(vdc, 0, "[%d] Different disk size from vds "
4393 			    "(old=0x%lx - new=0x%lx", vdc->instance,
4394 			    vdc->vdisk_size, attr_msg->vdisk_size)
4395 			status = EINVAL;
4396 			break;
4397 		}
4398 
4399 		vdc->vdisk_size = attr_msg->vdisk_size;
4400 		vdc->vdisk_type = attr_msg->vdisk_type;
4401 		vdc->operations = attr_msg->operations;
4402 		if (vio_ver_is_supported(vdc->ver, 1, 1))
4403 			vdc->vdisk_media = attr_msg->vdisk_media;
4404 		else
4405 			vdc->vdisk_media = 0;
4406 
4407 		DMSG(vdc, 0, "[%d] max_xfer_sz: sent %lx acked %lx\n",
4408 		    vdc->instance, vdc->max_xfer_sz, attr_msg->max_xfer_sz);
4409 		DMSG(vdc, 0, "[%d] vdisk_block_size: sent %lx acked %x\n",
4410 		    vdc->instance, vdc->block_size,
4411 		    attr_msg->vdisk_block_size);
4412 
4413 		/*
4414 		 * We don't know at compile time what the vDisk server will
4415 		 * think are good values but we apply a large (arbitrary)
4416 		 * upper bound to prevent memory exhaustion in vdc if it was
4417 		 * allocating a DRing based of huge values sent by the server.
4418 		 * We probably will never exceed this except if the message
4419 		 * was garbage.
4420 		 */
4421 		if ((attr_msg->max_xfer_sz * attr_msg->vdisk_block_size) <=
4422 		    (PAGESIZE * DEV_BSIZE)) {
4423 			vdc->max_xfer_sz = attr_msg->max_xfer_sz;
4424 			vdc->block_size = attr_msg->vdisk_block_size;
4425 		} else {
4426 			DMSG(vdc, 0, "[%d] vds block transfer size too big;"
4427 			    " using max supported by vdc", vdc->instance);
4428 		}
4429 
4430 		if ((attr_msg->xfer_mode != VIO_DRING_MODE) ||
4431 		    (attr_msg->vdisk_size > INT64_MAX) ||
4432 		    (attr_msg->operations == 0) ||
4433 		    (attr_msg->vdisk_type > VD_DISK_TYPE_DISK)) {
4434 			DMSG(vdc, 0, "[%d] Invalid attributes from vds",
4435 			    vdc->instance);
4436 			status = EINVAL;
4437 			break;
4438 		}
4439 
4440 		/*
4441 		 * Now that we have received all attributes we can create a
4442 		 * fake geometry for the disk.
4443 		 */
4444 		vdc_create_fake_geometry(vdc);
4445 		break;
4446 
4447 	case VIO_SUBTYPE_NACK:
4448 		/*
4449 		 * vds could not handle the attributes we sent so we
4450 		 * stop negotiating.
4451 		 */
4452 		status = EPROTO;
4453 		break;
4454 
4455 	case VIO_SUBTYPE_INFO:
4456 		/*
4457 		 * Handle the case where vds starts the handshake
4458 		 * (for now; vdc is the only supported instigatior)
4459 		 */
4460 		status = ENOTSUP;
4461 		break;
4462 
4463 	default:
4464 		status = ENOTSUP;
4465 		break;
4466 	}
4467 
4468 	return (status);
4469 }
4470 
4471 /*
4472  * Function:
4473  *	vdc_handle_dring_reg_msg()
4474  *
4475  * Description:
4476  *
4477  * Arguments:
4478  *	vdc		- soft state pointer for this instance of the driver.
4479  *	dring_msg	- LDC message sent by vDisk server
4480  *
4481  * Return Code:
4482  *	0	- Success
4483  */
4484 static int
4485 vdc_handle_dring_reg_msg(vdc_t *vdc, vio_dring_reg_msg_t *dring_msg)
4486 {
4487 	int		status = 0;
4488 
4489 	ASSERT(vdc != NULL);
4490 	ASSERT(mutex_owned(&vdc->lock));
4491 
4492 	if (dring_msg->tag.vio_subtype_env != VIO_DRING_REG) {
4493 		return (EPROTO);
4494 	}
4495 
4496 	switch (dring_msg->tag.vio_subtype) {
4497 	case VIO_SUBTYPE_ACK:
4498 		/* save the received dring_ident */
4499 		vdc->dring_ident = dring_msg->dring_ident;
4500 		DMSG(vdc, 0, "[%d] Received dring ident=0x%lx\n",
4501 		    vdc->instance, vdc->dring_ident);
4502 		break;
4503 
4504 	case VIO_SUBTYPE_NACK:
4505 		/*
4506 		 * vds could not handle the DRing info we sent so we
4507 		 * stop negotiating.
4508 		 */
4509 		DMSG(vdc, 0, "[%d] server could not register DRing\n",
4510 		    vdc->instance);
4511 		status = EPROTO;
4512 		break;
4513 
4514 	case VIO_SUBTYPE_INFO:
4515 		/*
4516 		 * Handle the case where vds starts handshake
4517 		 * (for now only vdc is the instigatior)
4518 		 */
4519 		status = ENOTSUP;
4520 		break;
4521 	default:
4522 		status = ENOTSUP;
4523 	}
4524 
4525 	return (status);
4526 }
4527 
4528 /*
4529  * Function:
4530  *	vdc_verify_seq_num()
4531  *
4532  * Description:
4533  *	This functions verifies that the sequence number sent back by the vDisk
4534  *	server with the latest message is what is expected (i.e. it is greater
4535  *	than the last seq num sent by the vDisk server and less than or equal
4536  *	to the last seq num generated by vdc).
4537  *
4538  *	It then checks the request ID to see if any requests need processing
4539  *	in the DRing.
4540  *
4541  * Arguments:
4542  *	vdc		- soft state pointer for this instance of the driver.
4543  *	dring_msg	- pointer to the LDC message sent by vds
4544  *
4545  * Return Code:
4546  *	VDC_SEQ_NUM_TODO	- Message needs to be processed
4547  *	VDC_SEQ_NUM_SKIP	- Message has already been processed
4548  *	VDC_SEQ_NUM_INVALID	- The seq numbers are so out of sync,
4549  *				  vdc cannot deal with them
4550  */
4551 static int
4552 vdc_verify_seq_num(vdc_t *vdc, vio_dring_msg_t *dring_msg)
4553 {
4554 	ASSERT(vdc != NULL);
4555 	ASSERT(dring_msg != NULL);
4556 	ASSERT(mutex_owned(&vdc->lock));
4557 
4558 	/*
4559 	 * Check to see if the messages were responded to in the correct
4560 	 * order by vds.
4561 	 */
4562 	if ((dring_msg->seq_num <= vdc->seq_num_reply) ||
4563 	    (dring_msg->seq_num > vdc->seq_num)) {
4564 		DMSG(vdc, 0, "?[%d] Bogus sequence_number %lu: "
4565 		    "%lu > expected <= %lu (last proc req %lu sent %lu)\n",
4566 		    vdc->instance, dring_msg->seq_num,
4567 		    vdc->seq_num_reply, vdc->seq_num,
4568 		    vdc->req_id_proc, vdc->req_id);
4569 		return (VDC_SEQ_NUM_INVALID);
4570 	}
4571 	vdc->seq_num_reply = dring_msg->seq_num;
4572 
4573 	if (vdc->req_id_proc < vdc->req_id)
4574 		return (VDC_SEQ_NUM_TODO);
4575 	else
4576 		return (VDC_SEQ_NUM_SKIP);
4577 }
4578 
4579 
4580 /*
4581  * Function:
4582  *	vdc_is_supported_version()
4583  *
4584  * Description:
4585  *	This routine checks if the major/minor version numbers specified in
4586  *	'ver_msg' are supported. If not it finds the next version that is
4587  *	in the supported version list 'vdc_version[]' and sets the fields in
4588  *	'ver_msg' to those values
4589  *
4590  * Arguments:
4591  *	ver_msg	- LDC message sent by vDisk server
4592  *
4593  * Return Code:
4594  *	B_TRUE	- Success
4595  *	B_FALSE	- Version not supported
4596  */
4597 static boolean_t
4598 vdc_is_supported_version(vio_ver_msg_t *ver_msg)
4599 {
4600 	int vdc_num_versions = sizeof (vdc_version) / sizeof (vdc_version[0]);
4601 
4602 	for (int i = 0; i < vdc_num_versions; i++) {
4603 		ASSERT(vdc_version[i].major > 0);
4604 		ASSERT((i == 0) ||
4605 		    (vdc_version[i].major < vdc_version[i-1].major));
4606 
4607 		/*
4608 		 * If the major versions match, adjust the minor version, if
4609 		 * necessary, down to the highest value supported by this
4610 		 * client. The server should support all minor versions lower
4611 		 * than the value it sent
4612 		 */
4613 		if (ver_msg->ver_major == vdc_version[i].major) {
4614 			if (ver_msg->ver_minor > vdc_version[i].minor) {
4615 				DMSGX(0,
4616 				    "Adjusting minor version from %u to %u",
4617 				    ver_msg->ver_minor, vdc_version[i].minor);
4618 				ver_msg->ver_minor = vdc_version[i].minor;
4619 			}
4620 			return (B_TRUE);
4621 		}
4622 
4623 		/*
4624 		 * If the message contains a higher major version number, set
4625 		 * the message's major/minor versions to the current values
4626 		 * and return false, so this message will get resent with
4627 		 * these values, and the server will potentially try again
4628 		 * with the same or a lower version
4629 		 */
4630 		if (ver_msg->ver_major > vdc_version[i].major) {
4631 			ver_msg->ver_major = vdc_version[i].major;
4632 			ver_msg->ver_minor = vdc_version[i].minor;
4633 			DMSGX(0, "Suggesting major/minor (0x%x/0x%x)\n",
4634 			    ver_msg->ver_major, ver_msg->ver_minor);
4635 
4636 			return (B_FALSE);
4637 		}
4638 
4639 		/*
4640 		 * Otherwise, the message's major version is less than the
4641 		 * current major version, so continue the loop to the next
4642 		 * (lower) supported version
4643 		 */
4644 	}
4645 
4646 	/*
4647 	 * No common version was found; "ground" the version pair in the
4648 	 * message to terminate negotiation
4649 	 */
4650 	ver_msg->ver_major = 0;
4651 	ver_msg->ver_minor = 0;
4652 
4653 	return (B_FALSE);
4654 }
4655 /* -------------------------------------------------------------------------- */
4656 
4657 /*
4658  * DKIO(7) support
4659  */
4660 
4661 typedef struct vdc_dk_arg {
4662 	struct dk_callback	dkc;
4663 	int			mode;
4664 	dev_t			dev;
4665 	vdc_t			*vdc;
4666 } vdc_dk_arg_t;
4667 
4668 /*
4669  * Function:
4670  * 	vdc_dkio_flush_cb()
4671  *
4672  * Description:
4673  *	This routine is a callback for DKIOCFLUSHWRITECACHE which can be called
4674  *	by kernel code.
4675  *
4676  * Arguments:
4677  *	arg	- a pointer to a vdc_dk_arg_t structure.
4678  */
4679 void
4680 vdc_dkio_flush_cb(void *arg)
4681 {
4682 	struct vdc_dk_arg	*dk_arg = (struct vdc_dk_arg *)arg;
4683 	struct dk_callback	*dkc = NULL;
4684 	vdc_t			*vdc = NULL;
4685 	int			rv;
4686 
4687 	if (dk_arg == NULL) {
4688 		cmn_err(CE_NOTE, "?[Unk] DKIOCFLUSHWRITECACHE arg is NULL\n");
4689 		return;
4690 	}
4691 	dkc = &dk_arg->dkc;
4692 	vdc = dk_arg->vdc;
4693 	ASSERT(vdc != NULL);
4694 
4695 	rv = vdc_do_sync_op(vdc, VD_OP_FLUSH, NULL, 0,
4696 	    VDCPART(dk_arg->dev), 0, CB_SYNC, 0, VIO_both_dir, B_TRUE);
4697 	if (rv != 0) {
4698 		DMSG(vdc, 0, "[%d] DKIOCFLUSHWRITECACHE failed %d : model %x\n",
4699 		    vdc->instance, rv,
4700 		    ddi_model_convert_from(dk_arg->mode & FMODELS));
4701 	}
4702 
4703 	/*
4704 	 * Trigger the call back to notify the caller the the ioctl call has
4705 	 * been completed.
4706 	 */
4707 	if ((dk_arg->mode & FKIOCTL) &&
4708 	    (dkc != NULL) &&
4709 	    (dkc->dkc_callback != NULL)) {
4710 		ASSERT(dkc->dkc_cookie != NULL);
4711 		(*dkc->dkc_callback)(dkc->dkc_cookie, rv);
4712 	}
4713 
4714 	/* Indicate that one less DKIO write flush is outstanding */
4715 	mutex_enter(&vdc->lock);
4716 	vdc->dkio_flush_pending--;
4717 	ASSERT(vdc->dkio_flush_pending >= 0);
4718 	mutex_exit(&vdc->lock);
4719 
4720 	/* free the mem that was allocated when the callback was dispatched */
4721 	kmem_free(arg, sizeof (vdc_dk_arg_t));
4722 }
4723 
4724 /*
4725  * Function:
4726  * 	vdc_dkio_get_partition()
4727  *
4728  * Description:
4729  *	This function implements the DKIOCGAPART ioctl.
4730  *
4731  * Arguments:
4732  *	vdc	- soft state pointer
4733  *	arg	- a pointer to a dk_map[NDKMAP] or dk_map32[NDKMAP] structure
4734  *	flag	- ioctl flags
4735  */
4736 static int
4737 vdc_dkio_get_partition(vdc_t *vdc, caddr_t arg, int flag)
4738 {
4739 	struct dk_geom *geom;
4740 	struct vtoc *vtoc;
4741 	union {
4742 		struct dk_map map[NDKMAP];
4743 		struct dk_map32 map32[NDKMAP];
4744 	} data;
4745 	int i, rv, size;
4746 
4747 	mutex_enter(&vdc->lock);
4748 
4749 	if ((rv = vdc_validate_geometry(vdc)) != 0) {
4750 		mutex_exit(&vdc->lock);
4751 		return (rv);
4752 	}
4753 
4754 	vtoc = vdc->vtoc;
4755 	geom = vdc->geom;
4756 
4757 	if (ddi_model_convert_from(flag & FMODELS) == DDI_MODEL_ILP32) {
4758 
4759 		for (i = 0; i < vtoc->v_nparts; i++) {
4760 			data.map32[i].dkl_cylno = vtoc->v_part[i].p_start /
4761 			    (geom->dkg_nhead * geom->dkg_nsect);
4762 			data.map32[i].dkl_nblk = vtoc->v_part[i].p_size;
4763 		}
4764 		size = NDKMAP * sizeof (struct dk_map32);
4765 
4766 	} else {
4767 
4768 		for (i = 0; i < vtoc->v_nparts; i++) {
4769 			data.map[i].dkl_cylno = vtoc->v_part[i].p_start /
4770 			    (geom->dkg_nhead * geom->dkg_nsect);
4771 			data.map[i].dkl_nblk = vtoc->v_part[i].p_size;
4772 		}
4773 		size = NDKMAP * sizeof (struct dk_map);
4774 
4775 	}
4776 
4777 	mutex_exit(&vdc->lock);
4778 
4779 	if (ddi_copyout(&data, arg, size, flag) != 0)
4780 		return (EFAULT);
4781 
4782 	return (0);
4783 }
4784 
4785 /*
4786  * Function:
4787  * 	vdc_dioctl_rwcmd()
4788  *
4789  * Description:
4790  *	This function implements the DIOCTL_RWCMD ioctl. This ioctl is used
4791  *	for DKC_DIRECT disks to read or write at an absolute disk offset.
4792  *
4793  * Arguments:
4794  *	dev	- device
4795  *	arg	- a pointer to a dadkio_rwcmd or dadkio_rwcmd32 structure
4796  *	flag	- ioctl flags
4797  */
4798 static int
4799 vdc_dioctl_rwcmd(dev_t dev, caddr_t arg, int flag)
4800 {
4801 	struct dadkio_rwcmd32 rwcmd32;
4802 	struct dadkio_rwcmd rwcmd;
4803 	struct iovec aiov;
4804 	struct uio auio;
4805 	int rw, status;
4806 	struct buf *buf;
4807 
4808 	if (ddi_model_convert_from(flag & FMODELS) == DDI_MODEL_ILP32) {
4809 		if (ddi_copyin((caddr_t)arg, (caddr_t)&rwcmd32,
4810 		    sizeof (struct dadkio_rwcmd32), flag)) {
4811 			return (EFAULT);
4812 		}
4813 		rwcmd.cmd = rwcmd32.cmd;
4814 		rwcmd.flags = rwcmd32.flags;
4815 		rwcmd.blkaddr = (daddr_t)rwcmd32.blkaddr;
4816 		rwcmd.buflen = rwcmd32.buflen;
4817 		rwcmd.bufaddr = (caddr_t)(uintptr_t)rwcmd32.bufaddr;
4818 	} else {
4819 		if (ddi_copyin((caddr_t)arg, (caddr_t)&rwcmd,
4820 		    sizeof (struct dadkio_rwcmd), flag)) {
4821 			return (EFAULT);
4822 		}
4823 	}
4824 
4825 	switch (rwcmd.cmd) {
4826 	case DADKIO_RWCMD_READ:
4827 		rw = B_READ;
4828 		break;
4829 	case DADKIO_RWCMD_WRITE:
4830 		rw = B_WRITE;
4831 		break;
4832 	default:
4833 		return (EINVAL);
4834 	}
4835 
4836 	bzero((caddr_t)&aiov, sizeof (struct iovec));
4837 	aiov.iov_base   = rwcmd.bufaddr;
4838 	aiov.iov_len    = rwcmd.buflen;
4839 
4840 	bzero((caddr_t)&auio, sizeof (struct uio));
4841 	auio.uio_iov    = &aiov;
4842 	auio.uio_iovcnt = 1;
4843 	auio.uio_loffset = rwcmd.blkaddr * DEV_BSIZE;
4844 	auio.uio_resid  = rwcmd.buflen;
4845 	auio.uio_segflg = flag & FKIOCTL ? UIO_SYSSPACE : UIO_USERSPACE;
4846 
4847 	buf = kmem_alloc(sizeof (buf_t), KM_SLEEP);
4848 	bioinit(buf);
4849 	/*
4850 	 * We use the private field of buf to specify that this is an
4851 	 * I/O using an absolute offset.
4852 	 */
4853 	buf->b_private = (void *)VD_SLICE_NONE;
4854 
4855 	status = physio(vdc_strategy, buf, dev, rw, vdc_min, &auio);
4856 
4857 	biofini(buf);
4858 	kmem_free(buf, sizeof (buf_t));
4859 
4860 	return (status);
4861 }
4862 
4863 /*
4864  * Allocate a buffer for a VD_OP_SCSICMD operation. The size of the allocated
4865  * buffer is returned in alloc_len.
4866  */
4867 static vd_scsi_t *
4868 vdc_scsi_alloc(int cdb_len, int sense_len, int datain_len, int dataout_len,
4869     int *alloc_len)
4870 {
4871 	vd_scsi_t *vd_scsi;
4872 	int vd_scsi_len = VD_SCSI_SIZE;
4873 
4874 	vd_scsi_len += P2ROUNDUP(cdb_len, sizeof (uint64_t));
4875 	vd_scsi_len += P2ROUNDUP(sense_len, sizeof (uint64_t));
4876 	vd_scsi_len += P2ROUNDUP(datain_len, sizeof (uint64_t));
4877 	vd_scsi_len += P2ROUNDUP(dataout_len, sizeof (uint64_t));
4878 
4879 	ASSERT(vd_scsi_len % sizeof (uint64_t) == 0);
4880 
4881 	vd_scsi = kmem_zalloc(vd_scsi_len, KM_SLEEP);
4882 
4883 	vd_scsi->cdb_len = cdb_len;
4884 	vd_scsi->sense_len = sense_len;
4885 	vd_scsi->datain_len = datain_len;
4886 	vd_scsi->dataout_len = dataout_len;
4887 
4888 	*alloc_len = vd_scsi_len;
4889 
4890 	return (vd_scsi);
4891 }
4892 
4893 /*
4894  * Convert the status of a SCSI command to a Solaris return code.
4895  *
4896  * Arguments:
4897  *	vd_scsi		- The SCSI operation buffer.
4898  *	log_error	- indicate if an error message should be logged.
4899  *
4900  * Note that our SCSI error messages are rather primitive for the moment
4901  * and could be improved by decoding some data like the SCSI command and
4902  * the sense key.
4903  *
4904  * Return value:
4905  *	0		- Status is good.
4906  *	EACCES		- Status reports a reservation conflict.
4907  *	ENOTSUP		- Status reports a check condition and sense key
4908  *			  reports an illegal request.
4909  *	EIO		- Any other status.
4910  */
4911 static int
4912 vdc_scsi_status(vdc_t *vdc, vd_scsi_t *vd_scsi, boolean_t log_error)
4913 {
4914 	int rv;
4915 	char path_str[MAXPATHLEN];
4916 	char panic_str[VDC_RESV_CONFLICT_FMT_LEN + MAXPATHLEN];
4917 	union scsi_cdb *cdb;
4918 	struct scsi_extended_sense *sense;
4919 
4920 	if (vd_scsi->cmd_status == STATUS_GOOD)
4921 		/* no error */
4922 		return (0);
4923 
4924 	/* when the tunable vdc_scsi_log_error is true we log all errors */
4925 	if (vdc_scsi_log_error)
4926 		log_error = B_TRUE;
4927 
4928 	if (log_error) {
4929 		cmn_err(CE_WARN, "%s (vdc%d):\tError for Command: 0x%x)\n",
4930 		    ddi_pathname(vdc->dip, path_str), vdc->instance,
4931 		    GETCMD(VD_SCSI_DATA_CDB(vd_scsi)));
4932 	}
4933 
4934 	/* default returned value */
4935 	rv = EIO;
4936 
4937 	switch (vd_scsi->cmd_status) {
4938 
4939 	case STATUS_CHECK:
4940 	case STATUS_TERMINATED:
4941 		if (log_error)
4942 			cmn_err(CE_CONT, "\tCheck Condition Error\n");
4943 
4944 		/* check sense buffer */
4945 		if (vd_scsi->sense_len == 0 ||
4946 		    vd_scsi->sense_status != STATUS_GOOD) {
4947 			if (log_error)
4948 				cmn_err(CE_CONT, "\tNo Sense Data Available\n");
4949 			break;
4950 		}
4951 
4952 		sense = VD_SCSI_DATA_SENSE(vd_scsi);
4953 
4954 		if (log_error) {
4955 			cmn_err(CE_CONT, "\tSense Key:  0x%x\n"
4956 			    "\tASC: 0x%x, ASCQ: 0x%x\n",
4957 			    scsi_sense_key((uint8_t *)sense),
4958 			    scsi_sense_asc((uint8_t *)sense),
4959 			    scsi_sense_ascq((uint8_t *)sense));
4960 		}
4961 
4962 		if (scsi_sense_key((uint8_t *)sense) == KEY_ILLEGAL_REQUEST)
4963 			rv = ENOTSUP;
4964 		break;
4965 
4966 	case STATUS_BUSY:
4967 		if (log_error)
4968 			cmn_err(CE_NOTE, "\tDevice Busy\n");
4969 		break;
4970 
4971 	case STATUS_RESERVATION_CONFLICT:
4972 		/*
4973 		 * If the command was PERSISTENT_RESERVATION_[IN|OUT] then
4974 		 * reservation conflict could be due to various reasons like
4975 		 * incorrect keys, not registered or not reserved etc. So,
4976 		 * we should not panic in that case.
4977 		 */
4978 		cdb = VD_SCSI_DATA_CDB(vd_scsi);
4979 		if (vdc->failfast_interval != 0 &&
4980 		    cdb->scc_cmd != SCMD_PERSISTENT_RESERVE_IN &&
4981 		    cdb->scc_cmd != SCMD_PERSISTENT_RESERVE_OUT) {
4982 			/* failfast is enabled so we have to panic */
4983 			(void) snprintf(panic_str, sizeof (panic_str),
4984 			    VDC_RESV_CONFLICT_FMT_STR "%s",
4985 			    ddi_pathname(vdc->dip, path_str));
4986 			panic(panic_str);
4987 		}
4988 		if (log_error)
4989 			cmn_err(CE_NOTE, "\tReservation Conflict\n");
4990 		rv = EACCES;
4991 		break;
4992 
4993 	case STATUS_QFULL:
4994 		if (log_error)
4995 			cmn_err(CE_NOTE, "\tQueue Full\n");
4996 		break;
4997 
4998 	case STATUS_MET:
4999 	case STATUS_INTERMEDIATE:
5000 	case STATUS_SCSI2:
5001 	case STATUS_INTERMEDIATE_MET:
5002 	case STATUS_ACA_ACTIVE:
5003 		if (log_error)
5004 			cmn_err(CE_CONT,
5005 			    "\tUnexpected SCSI status received: 0x%x\n",
5006 			    vd_scsi->cmd_status);
5007 		break;
5008 
5009 	default:
5010 		if (log_error)
5011 			cmn_err(CE_CONT,
5012 			    "\tInvalid SCSI status received: 0x%x\n",
5013 			    vd_scsi->cmd_status);
5014 		break;
5015 	}
5016 
5017 	return (rv);
5018 }
5019 
5020 /*
5021  * Implemented the USCSICMD uscsi(7I) ioctl. This ioctl is converted to
5022  * a VD_OP_SCSICMD operation which is sent to the vdisk server. If a SCSI
5023  * reset is requested (i.e. a flag USCSI_RESET* is set) then the ioctl is
5024  * converted to a VD_OP_RESET operation.
5025  */
5026 static int
5027 vdc_uscsi_cmd(vdc_t *vdc, caddr_t arg, int mode)
5028 {
5029 	struct uscsi_cmd 	uscsi;
5030 	struct uscsi_cmd32	uscsi32;
5031 	vd_scsi_t 		*vd_scsi;
5032 	int 			vd_scsi_len;
5033 	union scsi_cdb		*cdb;
5034 	struct scsi_extended_sense *sense;
5035 	char 			*datain, *dataout;
5036 	size_t			cdb_len, datain_len, dataout_len, sense_len;
5037 	int 			rv;
5038 
5039 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5040 		if (ddi_copyin(arg, &uscsi32, sizeof (struct uscsi_cmd32),
5041 		    mode) != 0)
5042 			return (EFAULT);
5043 		uscsi_cmd32touscsi_cmd((&uscsi32), (&uscsi));
5044 	} else {
5045 		if (ddi_copyin(arg, &uscsi, sizeof (struct uscsi_cmd),
5046 		    mode) != 0)
5047 			return (EFAULT);
5048 	}
5049 
5050 	/* a uscsi reset is converted to a VD_OP_RESET operation */
5051 	if (uscsi.uscsi_flags & (USCSI_RESET | USCSI_RESET_LUN |
5052 	    USCSI_RESET_ALL)) {
5053 		rv = vdc_do_sync_op(vdc, VD_OP_RESET, NULL, 0, 0, 0, CB_SYNC,
5054 		    (void *)(uint64_t)mode, VIO_both_dir, B_TRUE);
5055 		return (rv);
5056 	}
5057 
5058 	/* cdb buffer length */
5059 	cdb_len = uscsi.uscsi_cdblen;
5060 
5061 	/* data in and out buffers length */
5062 	if (uscsi.uscsi_flags & USCSI_READ) {
5063 		datain_len = uscsi.uscsi_buflen;
5064 		dataout_len = 0;
5065 	} else {
5066 		datain_len = 0;
5067 		dataout_len = uscsi.uscsi_buflen;
5068 	}
5069 
5070 	/* sense buffer length */
5071 	if (uscsi.uscsi_flags & USCSI_RQENABLE)
5072 		sense_len = uscsi.uscsi_rqlen;
5073 	else
5074 		sense_len = 0;
5075 
5076 	/* allocate buffer for the VD_SCSICMD_OP operation */
5077 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, datain_len, dataout_len,
5078 	    &vd_scsi_len);
5079 
5080 	/*
5081 	 * The documentation of USCSI_ISOLATE and USCSI_DIAGNOSE is very vague,
5082 	 * but basically they prevent a SCSI command from being retried in case
5083 	 * of an error.
5084 	 */
5085 	if ((uscsi.uscsi_flags & USCSI_ISOLATE) ||
5086 	    (uscsi.uscsi_flags & USCSI_DIAGNOSE))
5087 		vd_scsi->options |= VD_SCSI_OPT_NORETRY;
5088 
5089 	/* set task attribute */
5090 	if (uscsi.uscsi_flags & USCSI_NOTAG) {
5091 		vd_scsi->task_attribute = 0;
5092 	} else {
5093 		if (uscsi.uscsi_flags & USCSI_HEAD)
5094 			vd_scsi->task_attribute = VD_SCSI_TASK_ACA;
5095 		else if (uscsi.uscsi_flags & USCSI_HTAG)
5096 			vd_scsi->task_attribute = VD_SCSI_TASK_HQUEUE;
5097 		else if (uscsi.uscsi_flags & USCSI_OTAG)
5098 			vd_scsi->task_attribute = VD_SCSI_TASK_ORDERED;
5099 		else
5100 			vd_scsi->task_attribute = 0;
5101 	}
5102 
5103 	/* set timeout */
5104 	vd_scsi->timeout = uscsi.uscsi_timeout;
5105 
5106 	/* copy-in cdb data */
5107 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5108 	if (ddi_copyin(uscsi.uscsi_cdb, cdb, cdb_len, mode) != 0) {
5109 		rv = EFAULT;
5110 		goto done;
5111 	}
5112 
5113 	/* keep a pointer to the sense buffer */
5114 	sense = VD_SCSI_DATA_SENSE(vd_scsi);
5115 
5116 	/* keep a pointer to the data-in buffer */
5117 	datain = (char *)VD_SCSI_DATA_IN(vd_scsi);
5118 
5119 	/* copy-in request data to the data-out buffer */
5120 	dataout = (char *)VD_SCSI_DATA_OUT(vd_scsi);
5121 	if (!(uscsi.uscsi_flags & USCSI_READ)) {
5122 		if (ddi_copyin(uscsi.uscsi_bufaddr, dataout, dataout_len,
5123 		    mode)) {
5124 			rv = EFAULT;
5125 			goto done;
5126 		}
5127 	}
5128 
5129 	/* submit the request */
5130 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5131 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5132 
5133 	if (rv != 0)
5134 		goto done;
5135 
5136 	/* update scsi status */
5137 	uscsi.uscsi_status = vd_scsi->cmd_status;
5138 
5139 	/* update sense data */
5140 	if ((uscsi.uscsi_flags & USCSI_RQENABLE) &&
5141 	    (uscsi.uscsi_status == STATUS_CHECK ||
5142 	    uscsi.uscsi_status == STATUS_TERMINATED)) {
5143 
5144 		uscsi.uscsi_rqstatus = vd_scsi->sense_status;
5145 
5146 		if (uscsi.uscsi_rqstatus == STATUS_GOOD) {
5147 			uscsi.uscsi_rqresid = uscsi.uscsi_rqlen -
5148 			    vd_scsi->sense_len;
5149 			if (ddi_copyout(sense, uscsi.uscsi_rqbuf,
5150 			    vd_scsi->sense_len, mode) != 0) {
5151 				rv = EFAULT;
5152 				goto done;
5153 			}
5154 		}
5155 	}
5156 
5157 	/* update request data */
5158 	if (uscsi.uscsi_status == STATUS_GOOD) {
5159 		if (uscsi.uscsi_flags & USCSI_READ) {
5160 			uscsi.uscsi_resid = uscsi.uscsi_buflen -
5161 			    vd_scsi->datain_len;
5162 			if (ddi_copyout(datain, uscsi.uscsi_bufaddr,
5163 			    vd_scsi->datain_len, mode) != 0) {
5164 				rv = EFAULT;
5165 				goto done;
5166 			}
5167 		} else {
5168 			uscsi.uscsi_resid = uscsi.uscsi_buflen -
5169 			    vd_scsi->dataout_len;
5170 		}
5171 	}
5172 
5173 	/* copy-out result */
5174 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5175 		uscsi_cmdtouscsi_cmd32((&uscsi), (&uscsi32));
5176 		if (ddi_copyout(&uscsi32, arg, sizeof (struct uscsi_cmd32),
5177 		    mode) != 0) {
5178 			rv = EFAULT;
5179 			goto done;
5180 		}
5181 	} else {
5182 		if (ddi_copyout(&uscsi, arg, sizeof (struct uscsi_cmd),
5183 		    mode) != 0) {
5184 			rv = EFAULT;
5185 			goto done;
5186 		}
5187 	}
5188 
5189 	/* get the return code from the SCSI command status */
5190 	rv = vdc_scsi_status(vdc, vd_scsi,
5191 	    !(uscsi.uscsi_flags & USCSI_SILENT));
5192 
5193 done:
5194 	kmem_free(vd_scsi, vd_scsi_len);
5195 	return (rv);
5196 }
5197 
5198 /*
5199  * Create a VD_OP_SCSICMD buffer for a SCSI PERSISTENT IN command.
5200  *
5201  * Arguments:
5202  *	cmd		- SCSI PERSISTENT IN command
5203  *	len		- length of the SCSI input buffer
5204  *	vd_scsi_len	- return the length of the allocated buffer
5205  *
5206  * Returned Value:
5207  *	a pointer to the allocated VD_OP_SCSICMD buffer.
5208  */
5209 static vd_scsi_t *
5210 vdc_scsi_alloc_persistent_in(uchar_t cmd, int len, int *vd_scsi_len)
5211 {
5212 	int cdb_len, sense_len, datain_len, dataout_len;
5213 	vd_scsi_t *vd_scsi;
5214 	union scsi_cdb *cdb;
5215 
5216 	cdb_len = CDB_GROUP1;
5217 	sense_len = sizeof (struct scsi_extended_sense);
5218 	datain_len = len;
5219 	dataout_len = 0;
5220 
5221 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, datain_len, dataout_len,
5222 	    vd_scsi_len);
5223 
5224 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5225 
5226 	/* set cdb */
5227 	cdb->scc_cmd = SCMD_PERSISTENT_RESERVE_IN;
5228 	cdb->cdb_opaque[1] = cmd;
5229 	FORMG1COUNT(cdb, datain_len);
5230 
5231 	vd_scsi->timeout = vdc_scsi_timeout;
5232 
5233 	return (vd_scsi);
5234 }
5235 
5236 /*
5237  * Create a VD_OP_SCSICMD buffer for a SCSI PERSISTENT OUT command.
5238  *
5239  * Arguments:
5240  *	cmd		- SCSI PERSISTENT OUT command
5241  *	len		- length of the SCSI output buffer
5242  *	vd_scsi_len	- return the length of the allocated buffer
5243  *
5244  * Returned Code:
5245  *	a pointer to the allocated VD_OP_SCSICMD buffer.
5246  */
5247 static vd_scsi_t *
5248 vdc_scsi_alloc_persistent_out(uchar_t cmd, int len, int *vd_scsi_len)
5249 {
5250 	int cdb_len, sense_len, datain_len, dataout_len;
5251 	vd_scsi_t *vd_scsi;
5252 	union scsi_cdb *cdb;
5253 
5254 	cdb_len = CDB_GROUP1;
5255 	sense_len = sizeof (struct scsi_extended_sense);
5256 	datain_len = 0;
5257 	dataout_len = len;
5258 
5259 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, datain_len, dataout_len,
5260 	    vd_scsi_len);
5261 
5262 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5263 
5264 	/* set cdb */
5265 	cdb->scc_cmd = SCMD_PERSISTENT_RESERVE_OUT;
5266 	cdb->cdb_opaque[1] = cmd;
5267 	FORMG1COUNT(cdb, dataout_len);
5268 
5269 	vd_scsi->timeout = vdc_scsi_timeout;
5270 
5271 	return (vd_scsi);
5272 }
5273 
5274 /*
5275  * Implement the MHIOCGRP_INKEYS mhd(7i) ioctl. The ioctl is converted
5276  * to a SCSI PERSISTENT IN READ KEYS command which is sent to the vdisk
5277  * server with a VD_OP_SCSICMD operation.
5278  */
5279 static int
5280 vdc_mhd_inkeys(vdc_t *vdc, caddr_t arg, int mode)
5281 {
5282 	vd_scsi_t *vd_scsi;
5283 	mhioc_inkeys_t inkeys;
5284 	mhioc_key_list_t klist;
5285 	struct mhioc_inkeys32 inkeys32;
5286 	struct mhioc_key_list32 klist32;
5287 	sd_prin_readkeys_t *scsi_keys;
5288 	void *user_keys;
5289 	int vd_scsi_len;
5290 	int listsize, listlen, rv;
5291 
5292 	/* copyin arguments */
5293 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5294 		rv = ddi_copyin(arg, &inkeys32, sizeof (inkeys32), mode);
5295 		if (rv != 0)
5296 			return (EFAULT);
5297 
5298 		rv = ddi_copyin((caddr_t)(uintptr_t)inkeys32.li, &klist32,
5299 		    sizeof (klist32), mode);
5300 		if (rv != 0)
5301 			return (EFAULT);
5302 
5303 		listsize = klist32.listsize;
5304 	} else {
5305 		rv = ddi_copyin(arg, &inkeys, sizeof (inkeys), mode);
5306 		if (rv != 0)
5307 			return (EFAULT);
5308 
5309 		rv = ddi_copyin(inkeys.li, &klist, sizeof (klist), mode);
5310 		if (rv != 0)
5311 			return (EFAULT);
5312 
5313 		listsize = klist.listsize;
5314 	}
5315 
5316 	/* build SCSI VD_OP request */
5317 	vd_scsi = vdc_scsi_alloc_persistent_in(SD_READ_KEYS,
5318 	    sizeof (sd_prin_readkeys_t) - sizeof (caddr_t) +
5319 	    (sizeof (mhioc_resv_key_t) * listsize), &vd_scsi_len);
5320 
5321 	scsi_keys = (sd_prin_readkeys_t *)VD_SCSI_DATA_IN(vd_scsi);
5322 
5323 	/* submit the request */
5324 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5325 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5326 
5327 	if (rv != 0)
5328 		goto done;
5329 
5330 	listlen = scsi_keys->len / MHIOC_RESV_KEY_SIZE;
5331 
5332 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5333 		inkeys32.generation = scsi_keys->generation;
5334 		rv = ddi_copyout(&inkeys32, arg, sizeof (inkeys32), mode);
5335 		if (rv != 0) {
5336 			rv = EFAULT;
5337 			goto done;
5338 		}
5339 
5340 		klist32.listlen = listlen;
5341 		rv = ddi_copyout(&klist32, (caddr_t)(uintptr_t)inkeys32.li,
5342 		    sizeof (klist32), mode);
5343 		if (rv != 0) {
5344 			rv = EFAULT;
5345 			goto done;
5346 		}
5347 
5348 		user_keys = (caddr_t)(uintptr_t)klist32.list;
5349 	} else {
5350 		inkeys.generation = scsi_keys->generation;
5351 		rv = ddi_copyout(&inkeys, arg, sizeof (inkeys), mode);
5352 		if (rv != 0) {
5353 			rv = EFAULT;
5354 			goto done;
5355 		}
5356 
5357 		klist.listlen = listlen;
5358 		rv = ddi_copyout(&klist, inkeys.li, sizeof (klist), mode);
5359 		if (rv != 0) {
5360 			rv = EFAULT;
5361 			goto done;
5362 		}
5363 
5364 		user_keys = klist.list;
5365 	}
5366 
5367 	/* copy out keys */
5368 	if (listlen > 0 && listsize > 0) {
5369 		if (listsize < listlen)
5370 			listlen = listsize;
5371 		rv = ddi_copyout(&scsi_keys->keylist, user_keys,
5372 		    listlen * MHIOC_RESV_KEY_SIZE, mode);
5373 		if (rv != 0)
5374 			rv = EFAULT;
5375 	}
5376 
5377 	if (rv == 0)
5378 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5379 
5380 done:
5381 	kmem_free(vd_scsi, vd_scsi_len);
5382 
5383 	return (rv);
5384 }
5385 
5386 /*
5387  * Implement the MHIOCGRP_INRESV mhd(7i) ioctl. The ioctl is converted
5388  * to a SCSI PERSISTENT IN READ RESERVATION command which is sent to
5389  * the vdisk server with a VD_OP_SCSICMD operation.
5390  */
5391 static int
5392 vdc_mhd_inresv(vdc_t *vdc, caddr_t arg, int mode)
5393 {
5394 	vd_scsi_t *vd_scsi;
5395 	mhioc_inresvs_t inresv;
5396 	mhioc_resv_desc_list_t rlist;
5397 	struct mhioc_inresvs32 inresv32;
5398 	struct mhioc_resv_desc_list32 rlist32;
5399 	mhioc_resv_desc_t mhd_resv;
5400 	sd_prin_readresv_t *scsi_resv;
5401 	sd_readresv_desc_t *resv;
5402 	mhioc_resv_desc_t *user_resv;
5403 	int vd_scsi_len;
5404 	int listsize, listlen, i, rv;
5405 
5406 	/* copyin arguments */
5407 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5408 		rv = ddi_copyin(arg, &inresv32, sizeof (inresv32), mode);
5409 		if (rv != 0)
5410 			return (EFAULT);
5411 
5412 		rv = ddi_copyin((caddr_t)(uintptr_t)inresv32.li, &rlist32,
5413 		    sizeof (rlist32), mode);
5414 		if (rv != 0)
5415 			return (EFAULT);
5416 
5417 		listsize = rlist32.listsize;
5418 	} else {
5419 		rv = ddi_copyin(arg, &inresv, sizeof (inresv), mode);
5420 		if (rv != 0)
5421 			return (EFAULT);
5422 
5423 		rv = ddi_copyin(inresv.li, &rlist, sizeof (rlist), mode);
5424 		if (rv != 0)
5425 			return (EFAULT);
5426 
5427 		listsize = rlist.listsize;
5428 	}
5429 
5430 	/* build SCSI VD_OP request */
5431 	vd_scsi = vdc_scsi_alloc_persistent_in(SD_READ_RESV,
5432 	    sizeof (sd_prin_readresv_t) - sizeof (caddr_t) +
5433 	    (SCSI3_RESV_DESC_LEN * listsize), &vd_scsi_len);
5434 
5435 	scsi_resv = (sd_prin_readresv_t *)VD_SCSI_DATA_IN(vd_scsi);
5436 
5437 	/* submit the request */
5438 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5439 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5440 
5441 	if (rv != 0)
5442 		goto done;
5443 
5444 	listlen = scsi_resv->len / SCSI3_RESV_DESC_LEN;
5445 
5446 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5447 		inresv32.generation = scsi_resv->generation;
5448 		rv = ddi_copyout(&inresv32, arg, sizeof (inresv32), mode);
5449 		if (rv != 0) {
5450 			rv = EFAULT;
5451 			goto done;
5452 		}
5453 
5454 		rlist32.listlen = listlen;
5455 		rv = ddi_copyout(&rlist32, (caddr_t)(uintptr_t)inresv32.li,
5456 		    sizeof (rlist32), mode);
5457 		if (rv != 0) {
5458 			rv = EFAULT;
5459 			goto done;
5460 		}
5461 
5462 		user_resv = (mhioc_resv_desc_t *)(uintptr_t)rlist32.list;
5463 	} else {
5464 		inresv.generation = scsi_resv->generation;
5465 		rv = ddi_copyout(&inresv, arg, sizeof (inresv), mode);
5466 		if (rv != 0) {
5467 			rv = EFAULT;
5468 			goto done;
5469 		}
5470 
5471 		rlist.listlen = listlen;
5472 		rv = ddi_copyout(&rlist, inresv.li, sizeof (rlist), mode);
5473 		if (rv != 0) {
5474 			rv = EFAULT;
5475 			goto done;
5476 		}
5477 
5478 		user_resv = rlist.list;
5479 	}
5480 
5481 	/* copy out reservations */
5482 	if (listsize > 0 && listlen > 0) {
5483 		if (listsize < listlen)
5484 			listlen = listsize;
5485 		resv = (sd_readresv_desc_t *)&scsi_resv->readresv_desc;
5486 
5487 		for (i = 0; i < listlen; i++) {
5488 			mhd_resv.type = resv->type;
5489 			mhd_resv.scope = resv->scope;
5490 			mhd_resv.scope_specific_addr =
5491 			    BE_32(resv->scope_specific_addr);
5492 			bcopy(&resv->resvkey, &mhd_resv.key,
5493 			    MHIOC_RESV_KEY_SIZE);
5494 
5495 			rv = ddi_copyout(&mhd_resv, user_resv,
5496 			    sizeof (mhd_resv), mode);
5497 			if (rv != 0) {
5498 				rv = EFAULT;
5499 				goto done;
5500 			}
5501 			resv++;
5502 			user_resv++;
5503 		}
5504 	}
5505 
5506 	if (rv == 0)
5507 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5508 
5509 done:
5510 	kmem_free(vd_scsi, vd_scsi_len);
5511 	return (rv);
5512 }
5513 
5514 /*
5515  * Implement the MHIOCGRP_REGISTER mhd(7i) ioctl. The ioctl is converted
5516  * to a SCSI PERSISTENT OUT REGISTER command which is sent to the vdisk
5517  * server with a VD_OP_SCSICMD operation.
5518  */
5519 static int
5520 vdc_mhd_register(vdc_t *vdc, caddr_t arg, int mode)
5521 {
5522 	vd_scsi_t *vd_scsi;
5523 	sd_prout_t *scsi_prout;
5524 	mhioc_register_t mhd_reg;
5525 	int vd_scsi_len, rv;
5526 
5527 	/* copyin arguments */
5528 	rv = ddi_copyin(arg, &mhd_reg, sizeof (mhd_reg), mode);
5529 	if (rv != 0)
5530 		return (EFAULT);
5531 
5532 	/* build SCSI VD_OP request */
5533 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_REGISTER,
5534 	    sizeof (sd_prout_t), &vd_scsi_len);
5535 
5536 	/* set parameters */
5537 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
5538 	bcopy(mhd_reg.oldkey.key, scsi_prout->res_key, MHIOC_RESV_KEY_SIZE);
5539 	bcopy(mhd_reg.newkey.key, scsi_prout->service_key, MHIOC_RESV_KEY_SIZE);
5540 	scsi_prout->aptpl = (uchar_t)mhd_reg.aptpl;
5541 
5542 	/* submit the request */
5543 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5544 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5545 
5546 	if (rv == 0)
5547 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5548 
5549 	kmem_free(vd_scsi, vd_scsi_len);
5550 	return (rv);
5551 }
5552 
5553 /*
5554  * Implement the MHIOCGRP_RESERVE mhd(7i) ioctl. The ioctl is converted
5555  * to a SCSI PERSISTENT OUT RESERVE command which is sent to the vdisk
5556  * server with a VD_OP_SCSICMD operation.
5557  */
5558 static int
5559 vdc_mhd_reserve(vdc_t *vdc, caddr_t arg, int mode)
5560 {
5561 	union scsi_cdb *cdb;
5562 	vd_scsi_t *vd_scsi;
5563 	sd_prout_t *scsi_prout;
5564 	mhioc_resv_desc_t mhd_resv;
5565 	int vd_scsi_len, rv;
5566 
5567 	/* copyin arguments */
5568 	rv = ddi_copyin(arg, &mhd_resv, sizeof (mhd_resv), mode);
5569 	if (rv != 0)
5570 		return (EFAULT);
5571 
5572 	/* build SCSI VD_OP request */
5573 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_RESERVE,
5574 	    sizeof (sd_prout_t), &vd_scsi_len);
5575 
5576 	/* set parameters */
5577 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5578 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
5579 	bcopy(mhd_resv.key.key, scsi_prout->res_key, MHIOC_RESV_KEY_SIZE);
5580 	scsi_prout->scope_address = mhd_resv.scope_specific_addr;
5581 	cdb->cdb_opaque[2] = mhd_resv.type;
5582 
5583 	/* submit the request */
5584 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5585 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5586 
5587 	if (rv == 0)
5588 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5589 
5590 	kmem_free(vd_scsi, vd_scsi_len);
5591 	return (rv);
5592 }
5593 
5594 /*
5595  * Implement the MHIOCGRP_PREEMPTANDABORT mhd(7i) ioctl. The ioctl is
5596  * converted to a SCSI PERSISTENT OUT PREEMPT AND ABORT command which
5597  * is sent to the vdisk server with a VD_OP_SCSICMD operation.
5598  */
5599 static int
5600 vdc_mhd_preemptabort(vdc_t *vdc, caddr_t arg, int mode)
5601 {
5602 	union scsi_cdb *cdb;
5603 	vd_scsi_t *vd_scsi;
5604 	sd_prout_t *scsi_prout;
5605 	mhioc_preemptandabort_t mhd_preempt;
5606 	int vd_scsi_len, rv;
5607 
5608 	/* copyin arguments */
5609 	rv = ddi_copyin(arg, &mhd_preempt, sizeof (mhd_preempt), mode);
5610 	if (rv != 0)
5611 		return (EFAULT);
5612 
5613 	/* build SCSI VD_OP request */
5614 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_PREEMPTANDABORT,
5615 	    sizeof (sd_prout_t), &vd_scsi_len);
5616 
5617 	/* set parameters */
5618 	vd_scsi->task_attribute = VD_SCSI_TASK_ACA;
5619 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5620 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
5621 	bcopy(mhd_preempt.resvdesc.key.key, scsi_prout->res_key,
5622 	    MHIOC_RESV_KEY_SIZE);
5623 	bcopy(mhd_preempt.victim_key.key, scsi_prout->service_key,
5624 	    MHIOC_RESV_KEY_SIZE);
5625 	scsi_prout->scope_address = mhd_preempt.resvdesc.scope_specific_addr;
5626 	cdb->cdb_opaque[2] = mhd_preempt.resvdesc.type;
5627 
5628 	/* submit the request */
5629 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5630 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5631 
5632 	if (rv == 0)
5633 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5634 
5635 	kmem_free(vd_scsi, vd_scsi_len);
5636 	return (rv);
5637 }
5638 
5639 /*
5640  * Implement the MHIOCGRP_REGISTERANDIGNOREKEY mhd(7i) ioctl. The ioctl
5641  * is converted to a SCSI PERSISTENT OUT REGISTER AND IGNORE EXISTING KEY
5642  * command which is sent to the vdisk server with a VD_OP_SCSICMD operation.
5643  */
5644 static int
5645 vdc_mhd_registerignore(vdc_t *vdc, caddr_t arg, int mode)
5646 {
5647 	vd_scsi_t *vd_scsi;
5648 	sd_prout_t *scsi_prout;
5649 	mhioc_registerandignorekey_t mhd_regi;
5650 	int vd_scsi_len, rv;
5651 
5652 	/* copyin arguments */
5653 	rv = ddi_copyin(arg, &mhd_regi, sizeof (mhd_regi), mode);
5654 	if (rv != 0)
5655 		return (EFAULT);
5656 
5657 	/* build SCSI VD_OP request */
5658 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_REGISTERANDIGNOREKEY,
5659 	    sizeof (sd_prout_t), &vd_scsi_len);
5660 
5661 	/* set parameters */
5662 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
5663 	bcopy(mhd_regi.newkey.key, scsi_prout->service_key,
5664 	    MHIOC_RESV_KEY_SIZE);
5665 	scsi_prout->aptpl = (uchar_t)mhd_regi.aptpl;
5666 
5667 	/* submit the request */
5668 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5669 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5670 
5671 	if (rv == 0)
5672 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5673 
5674 	kmem_free(vd_scsi, vd_scsi_len);
5675 	return (rv);
5676 }
5677 
5678 /*
5679  * This function is used by the failfast mechanism to send a SCSI command
5680  * to check for reservation conflict.
5681  */
5682 static int
5683 vdc_failfast_scsi_cmd(vdc_t *vdc, uchar_t scmd)
5684 {
5685 	int cdb_len, sense_len, vd_scsi_len;
5686 	vd_scsi_t *vd_scsi;
5687 	union scsi_cdb *cdb;
5688 	int rv;
5689 
5690 	ASSERT(scmd == SCMD_TEST_UNIT_READY || scmd == SCMD_WRITE_G1);
5691 
5692 	if (scmd == SCMD_WRITE_G1)
5693 		cdb_len = CDB_GROUP1;
5694 	else
5695 		cdb_len = CDB_GROUP0;
5696 
5697 	sense_len = sizeof (struct scsi_extended_sense);
5698 
5699 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, 0, 0, &vd_scsi_len);
5700 
5701 	/* set cdb */
5702 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5703 	cdb->scc_cmd = scmd;
5704 
5705 	vd_scsi->timeout = vdc_scsi_timeout;
5706 
5707 	/*
5708 	 * Submit the request. The last argument has to be B_FALSE so that
5709 	 * vdc_do_sync_op does not loop checking for reservation conflict if
5710 	 * the operation returns an error.
5711 	 */
5712 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5713 	    0, 0, CB_SYNC, (void *)(uint64_t)FKIOCTL, VIO_both_dir, B_FALSE);
5714 
5715 	if (rv == 0)
5716 		(void) vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5717 
5718 	kmem_free(vd_scsi, vd_scsi_len);
5719 	return (rv);
5720 }
5721 
5722 /*
5723  * This function is used by the failfast mechanism to check for reservation
5724  * conflict. It sends some SCSI commands which will fail with a reservation
5725  * conflict error if the system does not have access to the disk and this
5726  * will panic the system.
5727  *
5728  * Returned Code:
5729  *	0	- disk is accessible without reservation conflict error
5730  *	!= 0	- unable to check if disk is accessible
5731  */
5732 int
5733 vdc_failfast_check_resv(vdc_t *vdc)
5734 {
5735 	int failure = 0;
5736 
5737 	/*
5738 	 * Send a TEST UNIT READY command. The command will panic
5739 	 * the system if it fails with a reservation conflict.
5740 	 */
5741 	if (vdc_failfast_scsi_cmd(vdc, SCMD_TEST_UNIT_READY) != 0)
5742 		failure++;
5743 
5744 	/*
5745 	 * With SPC-3 compliant devices TEST UNIT READY will succeed on
5746 	 * a reserved device, so we also do a WRITE(10) of zero byte in
5747 	 * order to provoke a Reservation Conflict status on those newer
5748 	 * devices.
5749 	 */
5750 	if (vdc_failfast_scsi_cmd(vdc, SCMD_WRITE_G1) != 0)
5751 		failure++;
5752 
5753 	return (failure);
5754 }
5755 
5756 /*
5757  * Add a pending I/O to the failfast I/O queue. An I/O is added to this
5758  * queue when it has failed and failfast is enabled. Then we have to check
5759  * if it has failed because of a reservation conflict in which case we have
5760  * to panic the system.
5761  *
5762  * Async I/O should be queued with their block I/O data transfer structure
5763  * (buf). Sync I/O should be queued with buf = NULL.
5764  */
5765 static vdc_io_t *
5766 vdc_failfast_io_queue(vdc_t *vdc, struct buf *buf)
5767 {
5768 	vdc_io_t *vio;
5769 
5770 	ASSERT(MUTEX_HELD(&vdc->lock));
5771 
5772 	vio = kmem_alloc(sizeof (vdc_io_t), KM_SLEEP);
5773 	vio->vio_next = vdc->failfast_io_queue;
5774 	vio->vio_buf = buf;
5775 	vio->vio_qtime = ddi_get_lbolt();
5776 
5777 	vdc->failfast_io_queue = vio;
5778 
5779 	/* notify the failfast thread that a new I/O is queued */
5780 	cv_signal(&vdc->failfast_cv);
5781 
5782 	return (vio);
5783 }
5784 
5785 /*
5786  * Remove and complete I/O in the failfast I/O queue which have been
5787  * added after the indicated deadline. A deadline of 0 means that all
5788  * I/O have to be unqueued and marked as completed.
5789  */
5790 static void
5791 vdc_failfast_io_unqueue(vdc_t *vdc, clock_t deadline)
5792 {
5793 	vdc_io_t *vio, *vio_tmp;
5794 
5795 	ASSERT(MUTEX_HELD(&vdc->lock));
5796 
5797 	vio_tmp = NULL;
5798 	vio = vdc->failfast_io_queue;
5799 
5800 	if (deadline != 0) {
5801 		/*
5802 		 * Skip any io queued after the deadline. The failfast
5803 		 * I/O queue is ordered starting with the last I/O added
5804 		 * to the queue.
5805 		 */
5806 		while (vio != NULL && vio->vio_qtime > deadline) {
5807 			vio_tmp = vio;
5808 			vio = vio->vio_next;
5809 		}
5810 	}
5811 
5812 	if (vio == NULL)
5813 		/* nothing to unqueue */
5814 		return;
5815 
5816 	/* update the queue */
5817 	if (vio_tmp == NULL)
5818 		vdc->failfast_io_queue = NULL;
5819 	else
5820 		vio_tmp->vio_next = NULL;
5821 
5822 	/*
5823 	 * Complete unqueued I/O. Async I/O have a block I/O data transfer
5824 	 * structure (buf) and they are completed by calling biodone(). Sync
5825 	 * I/O do not have a buf and they are completed by setting the
5826 	 * vio_qtime to zero and signaling failfast_io_cv. In that case, the
5827 	 * thread waiting for the I/O to complete is responsible for freeing
5828 	 * the vio structure.
5829 	 */
5830 	while (vio != NULL) {
5831 		vio_tmp = vio->vio_next;
5832 		if (vio->vio_buf != NULL) {
5833 			biodone(vio->vio_buf);
5834 			kmem_free(vio, sizeof (vdc_io_t));
5835 		} else {
5836 			vio->vio_qtime = 0;
5837 		}
5838 		vio = vio_tmp;
5839 	}
5840 
5841 	cv_broadcast(&vdc->failfast_io_cv);
5842 }
5843 
5844 /*
5845  * Failfast Thread.
5846  *
5847  * While failfast is enabled, the failfast thread sends a TEST UNIT READY
5848  * and a zero size WRITE(10) SCSI commands on a regular basis to check that
5849  * we still have access to the disk. If a command fails with a RESERVATION
5850  * CONFLICT error then the system will immediatly panic.
5851  *
5852  * The failfast thread is also woken up when an I/O has failed. It then check
5853  * the access to the disk to ensure that the I/O failure was not due to a
5854  * reservation conflict.
5855  *
5856  * There is one failfast thread for each virtual disk for which failfast is
5857  * enabled. We could have only one thread sending requests for all disks but
5858  * this would need vdc to send asynchronous requests and to have callbacks to
5859  * process replies.
5860  */
5861 static void
5862 vdc_failfast_thread(void *arg)
5863 {
5864 	int status;
5865 	vdc_t *vdc = (vdc_t *)arg;
5866 	clock_t timeout, starttime;
5867 
5868 	mutex_enter(&vdc->lock);
5869 
5870 	while (vdc->failfast_interval != 0) {
5871 
5872 		starttime = ddi_get_lbolt();
5873 
5874 		mutex_exit(&vdc->lock);
5875 
5876 		/* check for reservation conflict */
5877 		status = vdc_failfast_check_resv(vdc);
5878 
5879 		mutex_enter(&vdc->lock);
5880 		/*
5881 		 * We have dropped the lock to send the SCSI command so we have
5882 		 * to check that failfast is still enabled.
5883 		 */
5884 		if (vdc->failfast_interval == 0)
5885 			break;
5886 
5887 		/*
5888 		 * If we have successfully check the disk access and there was
5889 		 * no reservation conflict then we can complete any I/O queued
5890 		 * before the last check.
5891 		 */
5892 		if (status == 0)
5893 			vdc_failfast_io_unqueue(vdc, starttime);
5894 
5895 		/* proceed again if some I/O are still in the queue */
5896 		if (vdc->failfast_io_queue != NULL)
5897 			continue;
5898 
5899 		timeout = ddi_get_lbolt() +
5900 		    drv_usectohz(vdc->failfast_interval);
5901 		(void) cv_timedwait(&vdc->failfast_cv, &vdc->lock, timeout);
5902 	}
5903 
5904 	/*
5905 	 * Failfast is being stop so we can complete any queued I/O.
5906 	 */
5907 	vdc_failfast_io_unqueue(vdc, 0);
5908 	vdc->failfast_thread = NULL;
5909 	mutex_exit(&vdc->lock);
5910 	thread_exit();
5911 }
5912 
5913 /*
5914  * Implement the MHIOCENFAILFAST mhd(7i) ioctl.
5915  */
5916 static int
5917 vdc_failfast(vdc_t *vdc, caddr_t arg, int mode)
5918 {
5919 	unsigned int mh_time;
5920 
5921 	if (ddi_copyin((void *)arg, &mh_time, sizeof (int), mode))
5922 		return (EFAULT);
5923 
5924 	mutex_enter(&vdc->lock);
5925 	if (mh_time != 0 && vdc->failfast_thread == NULL) {
5926 		vdc->failfast_thread = thread_create(NULL, 0,
5927 		    vdc_failfast_thread, vdc, 0, &p0, TS_RUN,
5928 		    v.v_maxsyspri - 2);
5929 	}
5930 
5931 	vdc->failfast_interval = mh_time * 1000;
5932 	cv_signal(&vdc->failfast_cv);
5933 	mutex_exit(&vdc->lock);
5934 
5935 	return (0);
5936 }
5937 
5938 /*
5939  * Implement the MHIOCTKOWN and MHIOCRELEASE mhd(7i) ioctls. These ioctls are
5940  * converted to VD_OP_SET_ACCESS operations.
5941  */
5942 static int
5943 vdc_access_set(vdc_t *vdc, uint64_t flags, int mode)
5944 {
5945 	int rv;
5946 
5947 	/* submit owership command request */
5948 	rv = vdc_do_sync_op(vdc, VD_OP_SET_ACCESS, (caddr_t)&flags,
5949 	    sizeof (uint64_t), 0, 0, CB_SYNC, (void *)(uint64_t)mode,
5950 	    VIO_both_dir, B_TRUE);
5951 
5952 	return (rv);
5953 }
5954 
5955 /*
5956  * Implement the MHIOCSTATUS mhd(7i) ioctl. This ioctl is converted to a
5957  * VD_OP_GET_ACCESS operation.
5958  */
5959 static int
5960 vdc_access_get(vdc_t *vdc, uint64_t *status, int mode)
5961 {
5962 	int rv;
5963 
5964 	/* submit owership command request */
5965 	rv = vdc_do_sync_op(vdc, VD_OP_GET_ACCESS, (caddr_t)status,
5966 	    sizeof (uint64_t), 0, 0, CB_SYNC, (void *)(uint64_t)mode,
5967 	    VIO_both_dir, B_TRUE);
5968 
5969 	return (rv);
5970 }
5971 
5972 /*
5973  * Disk Ownership Thread.
5974  *
5975  * When we have taken the ownership of a disk, this thread waits to be
5976  * notified when the LDC channel is reset so that it can recover the
5977  * ownership.
5978  *
5979  * Note that the thread handling the LDC reset (vdc_process_msg_thread())
5980  * can not be used to do the ownership recovery because it has to be
5981  * running to handle the reply message to the ownership operation.
5982  */
5983 static void
5984 vdc_ownership_thread(void *arg)
5985 {
5986 	vdc_t *vdc = (vdc_t *)arg;
5987 	clock_t timeout;
5988 	uint64_t status;
5989 
5990 	mutex_enter(&vdc->ownership_lock);
5991 	mutex_enter(&vdc->lock);
5992 
5993 	while (vdc->ownership & VDC_OWNERSHIP_WANTED) {
5994 
5995 		if ((vdc->ownership & VDC_OWNERSHIP_RESET) ||
5996 		    !(vdc->ownership & VDC_OWNERSHIP_GRANTED)) {
5997 			/*
5998 			 * There was a reset so the ownership has been lost,
5999 			 * try to recover. We do this without using the preempt
6000 			 * option so that we don't steal the ownership from
6001 			 * someone who has preempted us.
6002 			 */
6003 			DMSG(vdc, 0, "[%d] Ownership lost, recovering",
6004 			    vdc->instance);
6005 
6006 			vdc->ownership &= ~(VDC_OWNERSHIP_RESET |
6007 			    VDC_OWNERSHIP_GRANTED);
6008 
6009 			mutex_exit(&vdc->lock);
6010 
6011 			status = vdc_access_set(vdc, VD_ACCESS_SET_EXCLUSIVE |
6012 			    VD_ACCESS_SET_PRESERVE, FKIOCTL);
6013 
6014 			mutex_enter(&vdc->lock);
6015 
6016 			if (status == 0) {
6017 				DMSG(vdc, 0, "[%d] Ownership recovered",
6018 				    vdc->instance);
6019 				vdc->ownership |= VDC_OWNERSHIP_GRANTED;
6020 			} else {
6021 				DMSG(vdc, 0, "[%d] Fail to recover ownership",
6022 				    vdc->instance);
6023 			}
6024 
6025 		}
6026 
6027 		/*
6028 		 * If we have the ownership then we just wait for an event
6029 		 * to happen (LDC reset), otherwise we will retry to recover
6030 		 * after a delay.
6031 		 */
6032 		if (vdc->ownership & VDC_OWNERSHIP_GRANTED)
6033 			timeout = 0;
6034 		else
6035 			timeout = ddi_get_lbolt() +
6036 			    drv_usectohz(vdc_ownership_delay);
6037 
6038 		/* Release the ownership_lock and wait on the vdc lock */
6039 		mutex_exit(&vdc->ownership_lock);
6040 
6041 		if (timeout == 0)
6042 			(void) cv_wait(&vdc->ownership_cv, &vdc->lock);
6043 		else
6044 			(void) cv_timedwait(&vdc->ownership_cv,
6045 			    &vdc->lock, timeout);
6046 
6047 		mutex_exit(&vdc->lock);
6048 
6049 		mutex_enter(&vdc->ownership_lock);
6050 		mutex_enter(&vdc->lock);
6051 	}
6052 
6053 	vdc->ownership_thread = NULL;
6054 	mutex_exit(&vdc->lock);
6055 	mutex_exit(&vdc->ownership_lock);
6056 
6057 	thread_exit();
6058 }
6059 
6060 static void
6061 vdc_ownership_update(vdc_t *vdc, int ownership_flags)
6062 {
6063 	ASSERT(MUTEX_HELD(&vdc->ownership_lock));
6064 
6065 	mutex_enter(&vdc->lock);
6066 	vdc->ownership = ownership_flags;
6067 	if ((vdc->ownership & VDC_OWNERSHIP_WANTED) &&
6068 	    vdc->ownership_thread == NULL) {
6069 		/* start ownership thread */
6070 		vdc->ownership_thread = thread_create(NULL, 0,
6071 		    vdc_ownership_thread, vdc, 0, &p0, TS_RUN,
6072 		    v.v_maxsyspri - 2);
6073 	} else {
6074 		/* notify the ownership thread */
6075 		cv_signal(&vdc->ownership_cv);
6076 	}
6077 	mutex_exit(&vdc->lock);
6078 }
6079 
6080 /*
6081  * Get the size and the block size of a virtual disk from the vdisk server.
6082  * We need to use this operation when the vdisk_size attribute was not
6083  * available during the handshake with the vdisk server.
6084  */
6085 static int
6086 vdc_check_capacity(vdc_t *vdc)
6087 {
6088 	int rv = 0;
6089 	size_t alloc_len;
6090 	vd_capacity_t *vd_cap;
6091 
6092 	if (vdc->vdisk_size != 0)
6093 		return (0);
6094 
6095 	alloc_len = P2ROUNDUP(sizeof (vd_capacity_t), sizeof (uint64_t));
6096 
6097 	vd_cap = kmem_zalloc(alloc_len, KM_SLEEP);
6098 
6099 	rv = vdc_do_sync_op(vdc, VD_OP_GET_CAPACITY, (caddr_t)vd_cap, alloc_len,
6100 	    0, 0, CB_SYNC, (void *)(uint64_t)FKIOCTL, VIO_both_dir, B_TRUE);
6101 
6102 	if (rv == 0) {
6103 		if (vd_cap->vdisk_block_size != vdc->block_size ||
6104 		    vd_cap->vdisk_size == VD_SIZE_UNKNOWN ||
6105 		    vd_cap->vdisk_size == 0)
6106 			rv = EINVAL;
6107 		else
6108 			vdc->vdisk_size = vd_cap->vdisk_size;
6109 	}
6110 
6111 	kmem_free(vd_cap, alloc_len);
6112 	return (rv);
6113 }
6114 
6115 /*
6116  * This structure is used in the DKIO(7I) array below.
6117  */
6118 typedef struct vdc_dk_ioctl {
6119 	uint8_t		op;		/* VD_OP_XXX value */
6120 	int		cmd;		/* Solaris ioctl operation number */
6121 	size_t		nbytes;		/* size of structure to be copied */
6122 
6123 	/* function to convert between vDisk and Solaris structure formats */
6124 	int	(*convert)(vdc_t *vdc, void *vd_buf, void *ioctl_arg,
6125 	    int mode, int dir);
6126 } vdc_dk_ioctl_t;
6127 
6128 /*
6129  * Subset of DKIO(7I) operations currently supported
6130  */
6131 static vdc_dk_ioctl_t	dk_ioctl[] = {
6132 	{VD_OP_FLUSH,		DKIOCFLUSHWRITECACHE,	0,
6133 		vdc_null_copy_func},
6134 	{VD_OP_GET_WCE,		DKIOCGETWCE,		sizeof (int),
6135 		vdc_get_wce_convert},
6136 	{VD_OP_SET_WCE,		DKIOCSETWCE,		sizeof (int),
6137 		vdc_set_wce_convert},
6138 	{VD_OP_GET_VTOC,	DKIOCGVTOC,		sizeof (vd_vtoc_t),
6139 		vdc_get_vtoc_convert},
6140 	{VD_OP_SET_VTOC,	DKIOCSVTOC,		sizeof (vd_vtoc_t),
6141 		vdc_set_vtoc_convert},
6142 	{VD_OP_GET_DISKGEOM,	DKIOCGGEOM,		sizeof (vd_geom_t),
6143 		vdc_get_geom_convert},
6144 	{VD_OP_GET_DISKGEOM,	DKIOCG_PHYGEOM,		sizeof (vd_geom_t),
6145 		vdc_get_geom_convert},
6146 	{VD_OP_GET_DISKGEOM, 	DKIOCG_VIRTGEOM,	sizeof (vd_geom_t),
6147 		vdc_get_geom_convert},
6148 	{VD_OP_SET_DISKGEOM,	DKIOCSGEOM,		sizeof (vd_geom_t),
6149 		vdc_set_geom_convert},
6150 	{VD_OP_GET_EFI,		DKIOCGETEFI,		0,
6151 		vdc_get_efi_convert},
6152 	{VD_OP_SET_EFI,		DKIOCSETEFI,		0,
6153 		vdc_set_efi_convert},
6154 
6155 	/* DIOCTL_RWCMD is converted to a read or a write */
6156 	{0, DIOCTL_RWCMD,  sizeof (struct dadkio_rwcmd), NULL},
6157 
6158 	/* mhd(7I) non-shared multihost disks ioctls */
6159 	{0, MHIOCTKOWN,				0, vdc_null_copy_func},
6160 	{0, MHIOCRELEASE,			0, vdc_null_copy_func},
6161 	{0, MHIOCSTATUS,			0, vdc_null_copy_func},
6162 	{0, MHIOCQRESERVE,			0, vdc_null_copy_func},
6163 
6164 	/* mhd(7I) shared multihost disks ioctls */
6165 	{0, MHIOCGRP_INKEYS,			0, vdc_null_copy_func},
6166 	{0, MHIOCGRP_INRESV,			0, vdc_null_copy_func},
6167 	{0, MHIOCGRP_REGISTER,			0, vdc_null_copy_func},
6168 	{0, MHIOCGRP_RESERVE, 			0, vdc_null_copy_func},
6169 	{0, MHIOCGRP_PREEMPTANDABORT,		0, vdc_null_copy_func},
6170 	{0, MHIOCGRP_REGISTERANDIGNOREKEY,	0, vdc_null_copy_func},
6171 
6172 	/* mhd(7I) failfast ioctl */
6173 	{0, MHIOCENFAILFAST,			0, vdc_null_copy_func},
6174 
6175 	/*
6176 	 * These particular ioctls are not sent to the server - vdc fakes up
6177 	 * the necessary info.
6178 	 */
6179 	{0, DKIOCINFO, sizeof (struct dk_cinfo), vdc_null_copy_func},
6180 	{0, DKIOCGMEDIAINFO, sizeof (struct dk_minfo), vdc_null_copy_func},
6181 	{0, USCSICMD,	sizeof (struct uscsi_cmd), vdc_null_copy_func},
6182 	{0, DKIOCGAPART, 0, vdc_null_copy_func },
6183 	{0, DKIOCREMOVABLE, 0, vdc_null_copy_func},
6184 	{0, CDROMREADOFFSET, 0, vdc_null_copy_func}
6185 };
6186 
6187 /*
6188  * The signature of vd_process_ioctl() has changed to include the return value
6189  * pointer. However we don't want to change vd_efi_* functions now so we add
6190  * this wrapper function so that we can use it with vdc_efi_init().
6191  *
6192  * vd_efi_* functions need some changes to fix 6528974 and so we will eventually
6193  * remove this function when fixing that bug.
6194  */
6195 static int
6196 vd_process_efi_ioctl(dev_t dev, int cmd, caddr_t arg, int mode)
6197 {
6198 	int rval;
6199 	return (vd_process_ioctl(dev, cmd, arg, mode, &rval));
6200 }
6201 
6202 /*
6203  * Function:
6204  *	vd_process_ioctl()
6205  *
6206  * Description:
6207  *	This routine processes disk specific ioctl calls
6208  *
6209  * Arguments:
6210  *	dev	- the device number
6211  *	cmd	- the operation [dkio(7I)] to be processed
6212  *	arg	- pointer to user provided structure
6213  *		  (contains data to be set or reference parameter for get)
6214  *	mode	- bit flag, indicating open settings, 32/64 bit type, etc
6215  *	rvalp	- pointer to return value for calling process.
6216  *
6217  * Return Code:
6218  *	0
6219  *	EFAULT
6220  *	ENXIO
6221  *	EIO
6222  *	ENOTSUP
6223  */
6224 static int
6225 vd_process_ioctl(dev_t dev, int cmd, caddr_t arg, int mode, int *rvalp)
6226 {
6227 	int		instance = VDCUNIT(dev);
6228 	vdc_t		*vdc = NULL;
6229 	int		rv = -1;
6230 	int		idx = 0;		/* index into dk_ioctl[] */
6231 	size_t		len = 0;		/* #bytes to send to vds */
6232 	size_t		alloc_len = 0;		/* #bytes to allocate mem for */
6233 	caddr_t		mem_p = NULL;
6234 	size_t		nioctls = (sizeof (dk_ioctl)) / (sizeof (dk_ioctl[0]));
6235 	vdc_dk_ioctl_t	*iop;
6236 
6237 	vdc = ddi_get_soft_state(vdc_state, instance);
6238 	if (vdc == NULL) {
6239 		cmn_err(CE_NOTE, "![%d] Could not get soft state structure",
6240 		    instance);
6241 		return (ENXIO);
6242 	}
6243 
6244 	DMSG(vdc, 0, "[%d] Processing ioctl(%x) for dev %lx : model %x\n",
6245 	    instance, cmd, dev, ddi_model_convert_from(mode & FMODELS));
6246 
6247 	if (rvalp != NULL) {
6248 		/* the return value of the ioctl is 0 by default */
6249 		*rvalp = 0;
6250 	}
6251 
6252 	/*
6253 	 * Validate the ioctl operation to be performed.
6254 	 *
6255 	 * If we have looped through the array without finding a match then we
6256 	 * don't support this ioctl.
6257 	 */
6258 	for (idx = 0; idx < nioctls; idx++) {
6259 		if (cmd == dk_ioctl[idx].cmd)
6260 			break;
6261 	}
6262 
6263 	if (idx >= nioctls) {
6264 		DMSG(vdc, 0, "[%d] Unsupported ioctl (0x%x)\n",
6265 		    vdc->instance, cmd);
6266 		return (ENOTSUP);
6267 	}
6268 
6269 	iop = &(dk_ioctl[idx]);
6270 
6271 	if (cmd == DKIOCGETEFI || cmd == DKIOCSETEFI) {
6272 		/* size is not fixed for EFI ioctls, it depends on ioctl arg */
6273 		dk_efi_t	dk_efi;
6274 
6275 		rv = ddi_copyin(arg, &dk_efi, sizeof (dk_efi_t), mode);
6276 		if (rv != 0)
6277 			return (EFAULT);
6278 
6279 		len = sizeof (vd_efi_t) - 1 + dk_efi.dki_length;
6280 	} else {
6281 		len = iop->nbytes;
6282 	}
6283 
6284 	/* check if the ioctl is applicable */
6285 	switch (cmd) {
6286 	case CDROMREADOFFSET:
6287 	case DKIOCREMOVABLE:
6288 		return (ENOTTY);
6289 
6290 	case USCSICMD:
6291 	case MHIOCTKOWN:
6292 	case MHIOCSTATUS:
6293 	case MHIOCQRESERVE:
6294 	case MHIOCRELEASE:
6295 	case MHIOCGRP_INKEYS:
6296 	case MHIOCGRP_INRESV:
6297 	case MHIOCGRP_REGISTER:
6298 	case MHIOCGRP_RESERVE:
6299 	case MHIOCGRP_PREEMPTANDABORT:
6300 	case MHIOCGRP_REGISTERANDIGNOREKEY:
6301 	case MHIOCENFAILFAST:
6302 		if (vdc->cinfo == NULL)
6303 			return (ENXIO);
6304 		if (vdc->cinfo->dki_ctype != DKC_SCSI_CCS)
6305 			return (ENOTTY);
6306 		break;
6307 
6308 	case DIOCTL_RWCMD:
6309 		if (vdc->cinfo == NULL)
6310 			return (ENXIO);
6311 		if (vdc->cinfo->dki_ctype != DKC_DIRECT)
6312 			return (ENOTTY);
6313 		break;
6314 
6315 	case DKIOCINFO:
6316 		if (vdc->cinfo == NULL)
6317 			return (ENXIO);
6318 		break;
6319 
6320 	case DKIOCGMEDIAINFO:
6321 		if (vdc->minfo == NULL)
6322 			return (ENXIO);
6323 		if (vdc_check_capacity(vdc) != 0)
6324 			/* disk capacity is not available */
6325 			return (EIO);
6326 		break;
6327 	}
6328 
6329 	/*
6330 	 * Deal with ioctls which require a processing different than
6331 	 * converting ioctl arguments and sending a corresponding
6332 	 * VD operation.
6333 	 */
6334 	switch (cmd) {
6335 
6336 	case USCSICMD:
6337 	{
6338 		return (vdc_uscsi_cmd(vdc, arg, mode));
6339 	}
6340 
6341 	case MHIOCTKOWN:
6342 	{
6343 		mutex_enter(&vdc->ownership_lock);
6344 		/*
6345 		 * We have to set VDC_OWNERSHIP_WANTED now so that the ownership
6346 		 * can be flagged with VDC_OWNERSHIP_RESET if the LDC is reset
6347 		 * while we are processing the ioctl.
6348 		 */
6349 		vdc_ownership_update(vdc, VDC_OWNERSHIP_WANTED);
6350 
6351 		rv = vdc_access_set(vdc, VD_ACCESS_SET_EXCLUSIVE |
6352 		    VD_ACCESS_SET_PREEMPT | VD_ACCESS_SET_PRESERVE, mode);
6353 		if (rv == 0) {
6354 			vdc_ownership_update(vdc, VDC_OWNERSHIP_WANTED |
6355 			    VDC_OWNERSHIP_GRANTED);
6356 		} else {
6357 			vdc_ownership_update(vdc, VDC_OWNERSHIP_NONE);
6358 		}
6359 		mutex_exit(&vdc->ownership_lock);
6360 		return (rv);
6361 	}
6362 
6363 	case MHIOCRELEASE:
6364 	{
6365 		mutex_enter(&vdc->ownership_lock);
6366 		rv = vdc_access_set(vdc, VD_ACCESS_SET_CLEAR, mode);
6367 		if (rv == 0) {
6368 			vdc_ownership_update(vdc, VDC_OWNERSHIP_NONE);
6369 		}
6370 		mutex_exit(&vdc->ownership_lock);
6371 		return (rv);
6372 	}
6373 
6374 	case MHIOCSTATUS:
6375 	{
6376 		uint64_t status;
6377 
6378 		rv = vdc_access_get(vdc, &status, mode);
6379 		if (rv == 0 && rvalp != NULL)
6380 			*rvalp = (status & VD_ACCESS_ALLOWED)? 0 : 1;
6381 		return (rv);
6382 	}
6383 
6384 	case MHIOCQRESERVE:
6385 	{
6386 		rv = vdc_access_set(vdc, VD_ACCESS_SET_EXCLUSIVE, mode);
6387 		return (rv);
6388 	}
6389 
6390 	case MHIOCGRP_INKEYS:
6391 	{
6392 		return (vdc_mhd_inkeys(vdc, arg, mode));
6393 	}
6394 
6395 	case MHIOCGRP_INRESV:
6396 	{
6397 		return (vdc_mhd_inresv(vdc, arg, mode));
6398 	}
6399 
6400 	case MHIOCGRP_REGISTER:
6401 	{
6402 		return (vdc_mhd_register(vdc, arg, mode));
6403 	}
6404 
6405 	case MHIOCGRP_RESERVE:
6406 	{
6407 		return (vdc_mhd_reserve(vdc, arg, mode));
6408 	}
6409 
6410 	case MHIOCGRP_PREEMPTANDABORT:
6411 	{
6412 		return (vdc_mhd_preemptabort(vdc, arg, mode));
6413 	}
6414 
6415 	case MHIOCGRP_REGISTERANDIGNOREKEY:
6416 	{
6417 		return (vdc_mhd_registerignore(vdc, arg, mode));
6418 	}
6419 
6420 	case MHIOCENFAILFAST:
6421 	{
6422 		rv = vdc_failfast(vdc, arg, mode);
6423 		return (rv);
6424 	}
6425 
6426 	case DIOCTL_RWCMD:
6427 	{
6428 		return (vdc_dioctl_rwcmd(dev, arg, mode));
6429 	}
6430 
6431 	case DKIOCGAPART:
6432 	{
6433 		return (vdc_dkio_get_partition(vdc, arg, mode));
6434 	}
6435 
6436 	case DKIOCINFO:
6437 	{
6438 		struct dk_cinfo	cinfo;
6439 
6440 		bcopy(vdc->cinfo, &cinfo, sizeof (struct dk_cinfo));
6441 		cinfo.dki_partition = VDCPART(dev);
6442 
6443 		rv = ddi_copyout(&cinfo, (void *)arg,
6444 		    sizeof (struct dk_cinfo), mode);
6445 		if (rv != 0)
6446 			return (EFAULT);
6447 
6448 		return (0);
6449 	}
6450 
6451 	case DKIOCGMEDIAINFO:
6452 	{
6453 		ASSERT(vdc->vdisk_size != 0);
6454 		if (vdc->minfo->dki_capacity == 0)
6455 			vdc->minfo->dki_capacity = vdc->vdisk_size;
6456 		rv = ddi_copyout(vdc->minfo, (void *)arg,
6457 		    sizeof (struct dk_minfo), mode);
6458 		if (rv != 0)
6459 			return (EFAULT);
6460 
6461 		return (0);
6462 	}
6463 
6464 	case DKIOCFLUSHWRITECACHE:
6465 		{
6466 			struct dk_callback *dkc =
6467 			    (struct dk_callback *)(uintptr_t)arg;
6468 			vdc_dk_arg_t	*dkarg = NULL;
6469 
6470 			DMSG(vdc, 1, "[%d] Flush W$: mode %x\n",
6471 			    instance, mode);
6472 
6473 			/*
6474 			 * If arg is NULL, then there is no callback function
6475 			 * registered and the call operates synchronously; we
6476 			 * break and continue with the rest of the function and
6477 			 * wait for vds to return (i.e. after the request to
6478 			 * vds returns successfully, all writes completed prior
6479 			 * to the ioctl will have been flushed from the disk
6480 			 * write cache to persistent media.
6481 			 *
6482 			 * If a callback function is registered, we dispatch
6483 			 * the request on a task queue and return immediately.
6484 			 * The callback will deal with informing the calling
6485 			 * thread that the flush request is completed.
6486 			 */
6487 			if (dkc == NULL)
6488 				break;
6489 
6490 			/*
6491 			 * the asynchronous callback is only supported if
6492 			 * invoked from within the kernel
6493 			 */
6494 			if ((mode & FKIOCTL) == 0)
6495 				return (ENOTSUP);
6496 
6497 			dkarg = kmem_zalloc(sizeof (vdc_dk_arg_t), KM_SLEEP);
6498 
6499 			dkarg->mode = mode;
6500 			dkarg->dev = dev;
6501 			bcopy(dkc, &dkarg->dkc, sizeof (*dkc));
6502 
6503 			mutex_enter(&vdc->lock);
6504 			vdc->dkio_flush_pending++;
6505 			dkarg->vdc = vdc;
6506 			mutex_exit(&vdc->lock);
6507 
6508 			/* put the request on a task queue */
6509 			rv = taskq_dispatch(system_taskq, vdc_dkio_flush_cb,
6510 			    (void *)dkarg, DDI_SLEEP);
6511 			if (rv == NULL) {
6512 				/* clean up if dispatch fails */
6513 				mutex_enter(&vdc->lock);
6514 				vdc->dkio_flush_pending--;
6515 				mutex_exit(&vdc->lock);
6516 				kmem_free(dkarg, sizeof (vdc_dk_arg_t));
6517 			}
6518 
6519 			return (rv == NULL ? ENOMEM : 0);
6520 		}
6521 	}
6522 
6523 	/* catch programming error in vdc - should be a VD_OP_XXX ioctl */
6524 	ASSERT(iop->op != 0);
6525 
6526 	/* check if the vDisk server handles the operation for this vDisk */
6527 	if (VD_OP_SUPPORTED(vdc->operations, iop->op) == B_FALSE) {
6528 		DMSG(vdc, 0, "[%d] Unsupported VD_OP operation (0x%x)\n",
6529 		    vdc->instance, iop->op);
6530 		return (ENOTSUP);
6531 	}
6532 
6533 	/* LDC requires that the memory being mapped is 8-byte aligned */
6534 	alloc_len = P2ROUNDUP(len, sizeof (uint64_t));
6535 	DMSG(vdc, 1, "[%d] struct size %ld alloc %ld\n",
6536 	    instance, len, alloc_len);
6537 
6538 	if (alloc_len > 0)
6539 		mem_p = kmem_zalloc(alloc_len, KM_SLEEP);
6540 
6541 	/*
6542 	 * Call the conversion function for this ioctl which, if necessary,
6543 	 * converts from the Solaris format to the format ARC'ed
6544 	 * as part of the vDisk protocol (FWARC 2006/195)
6545 	 */
6546 	ASSERT(iop->convert != NULL);
6547 	rv = (iop->convert)(vdc, arg, mem_p, mode, VD_COPYIN);
6548 	if (rv != 0) {
6549 		DMSG(vdc, 0, "[%d] convert func returned %d for ioctl 0x%x\n",
6550 		    instance, rv, cmd);
6551 		if (mem_p != NULL)
6552 			kmem_free(mem_p, alloc_len);
6553 		return (rv);
6554 	}
6555 
6556 	/*
6557 	 * send request to vds to service the ioctl.
6558 	 */
6559 	rv = vdc_do_sync_op(vdc, iop->op, mem_p, alloc_len,
6560 	    VDCPART(dev), 0, CB_SYNC, (void *)(uint64_t)mode,
6561 	    VIO_both_dir, B_TRUE);
6562 
6563 	if (rv != 0) {
6564 		/*
6565 		 * This is not necessarily an error. The ioctl could
6566 		 * be returning a value such as ENOTTY to indicate
6567 		 * that the ioctl is not applicable.
6568 		 */
6569 		DMSG(vdc, 0, "[%d] vds returned %d for ioctl 0x%x\n",
6570 		    instance, rv, cmd);
6571 		if (mem_p != NULL)
6572 			kmem_free(mem_p, alloc_len);
6573 
6574 		return (rv);
6575 	}
6576 
6577 	/*
6578 	 * Call the conversion function (if it exists) for this ioctl
6579 	 * which converts from the format ARC'ed as part of the vDisk
6580 	 * protocol (FWARC 2006/195) back to a format understood by
6581 	 * the rest of Solaris.
6582 	 */
6583 	rv = (iop->convert)(vdc, mem_p, arg, mode, VD_COPYOUT);
6584 	if (rv != 0) {
6585 		DMSG(vdc, 0, "[%d] convert func returned %d for ioctl 0x%x\n",
6586 		    instance, rv, cmd);
6587 		if (mem_p != NULL)
6588 			kmem_free(mem_p, alloc_len);
6589 		return (rv);
6590 	}
6591 
6592 	if (mem_p != NULL)
6593 		kmem_free(mem_p, alloc_len);
6594 
6595 	return (rv);
6596 }
6597 
6598 /*
6599  * Function:
6600  *
6601  * Description:
6602  *	This is an empty conversion function used by ioctl calls which
6603  *	do not need to convert the data being passed in/out to userland
6604  */
6605 static int
6606 vdc_null_copy_func(vdc_t *vdc, void *from, void *to, int mode, int dir)
6607 {
6608 	_NOTE(ARGUNUSED(vdc))
6609 	_NOTE(ARGUNUSED(from))
6610 	_NOTE(ARGUNUSED(to))
6611 	_NOTE(ARGUNUSED(mode))
6612 	_NOTE(ARGUNUSED(dir))
6613 
6614 	return (0);
6615 }
6616 
6617 static int
6618 vdc_get_wce_convert(vdc_t *vdc, void *from, void *to,
6619     int mode, int dir)
6620 {
6621 	_NOTE(ARGUNUSED(vdc))
6622 
6623 	if (dir == VD_COPYIN)
6624 		return (0);		/* nothing to do */
6625 
6626 	if (ddi_copyout(from, to, sizeof (int), mode) != 0)
6627 		return (EFAULT);
6628 
6629 	return (0);
6630 }
6631 
6632 static int
6633 vdc_set_wce_convert(vdc_t *vdc, void *from, void *to,
6634     int mode, int dir)
6635 {
6636 	_NOTE(ARGUNUSED(vdc))
6637 
6638 	if (dir == VD_COPYOUT)
6639 		return (0);		/* nothing to do */
6640 
6641 	if (ddi_copyin(from, to, sizeof (int), mode) != 0)
6642 		return (EFAULT);
6643 
6644 	return (0);
6645 }
6646 
6647 /*
6648  * Function:
6649  *	vdc_get_vtoc_convert()
6650  *
6651  * Description:
6652  *	This routine performs the necessary convertions from the DKIOCGVTOC
6653  *	Solaris structure to the format defined in FWARC 2006/195.
6654  *
6655  *	In the struct vtoc definition, the timestamp field is marked as not
6656  *	supported so it is not part of vDisk protocol (FWARC 2006/195).
6657  *	However SVM uses that field to check it can write into the VTOC,
6658  *	so we fake up the info of that field.
6659  *
6660  * Arguments:
6661  *	vdc	- the vDisk client
6662  *	from	- the buffer containing the data to be copied from
6663  *	to	- the buffer to be copied to
6664  *	mode	- flags passed to ioctl() call
6665  *	dir	- the "direction" of the copy - VD_COPYIN or VD_COPYOUT
6666  *
6667  * Return Code:
6668  *	0	- Success
6669  *	ENXIO	- incorrect buffer passed in.
6670  *	EFAULT	- ddi_copyout routine encountered an error.
6671  */
6672 static int
6673 vdc_get_vtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
6674 {
6675 	int		i;
6676 	void		*tmp_mem = NULL;
6677 	void		*tmp_memp;
6678 	struct vtoc	vt;
6679 	struct vtoc32	vt32;
6680 	int		copy_len = 0;
6681 	int		rv = 0;
6682 
6683 	if (dir != VD_COPYOUT)
6684 		return (0);	/* nothing to do */
6685 
6686 	if ((from == NULL) || (to == NULL))
6687 		return (ENXIO);
6688 
6689 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32)
6690 		copy_len = sizeof (struct vtoc32);
6691 	else
6692 		copy_len = sizeof (struct vtoc);
6693 
6694 	tmp_mem = kmem_alloc(copy_len, KM_SLEEP);
6695 
6696 	VD_VTOC2VTOC((vd_vtoc_t *)from, &vt);
6697 
6698 	/* fake the VTOC timestamp field */
6699 	for (i = 0; i < V_NUMPAR; i++) {
6700 		vt.timestamp[i] = vdc->vtoc->timestamp[i];
6701 	}
6702 
6703 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
6704 		/* LINTED E_ASSIGN_NARROW_CONV */
6705 		vtoctovtoc32(vt, vt32);
6706 		tmp_memp = &vt32;
6707 	} else {
6708 		tmp_memp = &vt;
6709 	}
6710 	rv = ddi_copyout(tmp_memp, to, copy_len, mode);
6711 	if (rv != 0)
6712 		rv = EFAULT;
6713 
6714 	kmem_free(tmp_mem, copy_len);
6715 	return (rv);
6716 }
6717 
6718 /*
6719  * Function:
6720  *	vdc_set_vtoc_convert()
6721  *
6722  * Description:
6723  *	This routine performs the necessary convertions from the DKIOCSVTOC
6724  *	Solaris structure to the format defined in FWARC 2006/195.
6725  *
6726  * Arguments:
6727  *	vdc	- the vDisk client
6728  *	from	- Buffer with data
6729  *	to	- Buffer where data is to be copied to
6730  *	mode	- flags passed to ioctl
6731  *	dir	- direction of copy (in or out)
6732  *
6733  * Return Code:
6734  *	0	- Success
6735  *	ENXIO	- Invalid buffer passed in
6736  *	EFAULT	- ddi_copyin of data failed
6737  */
6738 static int
6739 vdc_set_vtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
6740 {
6741 	_NOTE(ARGUNUSED(vdc))
6742 
6743 	void		*tmp_mem = NULL, *uvtoc;
6744 	struct vtoc	vt;
6745 	struct vtoc	*vtp = &vt;
6746 	vd_vtoc_t	vtvd;
6747 	int		copy_len = 0;
6748 	int		i, rv = 0;
6749 
6750 	if ((from == NULL) || (to == NULL))
6751 		return (ENXIO);
6752 
6753 	if (dir == VD_COPYIN)
6754 		uvtoc = from;
6755 	else
6756 		uvtoc = to;
6757 
6758 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32)
6759 		copy_len = sizeof (struct vtoc32);
6760 	else
6761 		copy_len = sizeof (struct vtoc);
6762 
6763 	tmp_mem = kmem_alloc(copy_len, KM_SLEEP);
6764 
6765 	rv = ddi_copyin(uvtoc, tmp_mem, copy_len, mode);
6766 	if (rv != 0) {
6767 		kmem_free(tmp_mem, copy_len);
6768 		return (EFAULT);
6769 	}
6770 
6771 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
6772 		vtoc32tovtoc((*(struct vtoc32 *)tmp_mem), vt);
6773 	} else {
6774 		vtp = tmp_mem;
6775 	}
6776 
6777 	if (dir == VD_COPYOUT) {
6778 		/*
6779 		 * The disk label may have changed. Revalidate the disk
6780 		 * geometry. This will also update the device nodes and
6781 		 * properties.
6782 		 */
6783 		vdc_validate(vdc);
6784 
6785 		/*
6786 		 * We also need to keep track of the timestamp fields.
6787 		 */
6788 		for (i = 0; i < V_NUMPAR; i++) {
6789 			vdc->vtoc->timestamp[i] = vtp->timestamp[i];
6790 		}
6791 
6792 		return (0);
6793 	}
6794 
6795 	VTOC2VD_VTOC(vtp, &vtvd);
6796 	bcopy(&vtvd, to, sizeof (vd_vtoc_t));
6797 	kmem_free(tmp_mem, copy_len);
6798 
6799 	return (0);
6800 }
6801 
6802 /*
6803  * Function:
6804  *	vdc_get_geom_convert()
6805  *
6806  * Description:
6807  *	This routine performs the necessary convertions from the DKIOCGGEOM,
6808  *	DKIOCG_PHYSGEOM and DKIOG_VIRTGEOM Solaris structures to the format
6809  *	defined in FWARC 2006/195
6810  *
6811  * Arguments:
6812  *	vdc	- the vDisk client
6813  *	from	- Buffer with data
6814  *	to	- Buffer where data is to be copied to
6815  *	mode	- flags passed to ioctl
6816  *	dir	- direction of copy (in or out)
6817  *
6818  * Return Code:
6819  *	0	- Success
6820  *	ENXIO	- Invalid buffer passed in
6821  *	EFAULT	- ddi_copyout of data failed
6822  */
6823 static int
6824 vdc_get_geom_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
6825 {
6826 	_NOTE(ARGUNUSED(vdc))
6827 
6828 	struct dk_geom	geom;
6829 	int	copy_len = sizeof (struct dk_geom);
6830 	int	rv = 0;
6831 
6832 	if (dir != VD_COPYOUT)
6833 		return (0);	/* nothing to do */
6834 
6835 	if ((from == NULL) || (to == NULL))
6836 		return (ENXIO);
6837 
6838 	VD_GEOM2DK_GEOM((vd_geom_t *)from, &geom);
6839 	rv = ddi_copyout(&geom, to, copy_len, mode);
6840 	if (rv != 0)
6841 		rv = EFAULT;
6842 
6843 	return (rv);
6844 }
6845 
6846 /*
6847  * Function:
6848  *	vdc_set_geom_convert()
6849  *
6850  * Description:
6851  *	This routine performs the necessary convertions from the DKIOCSGEOM
6852  *	Solaris structure to the format defined in FWARC 2006/195.
6853  *
6854  * Arguments:
6855  *	vdc	- the vDisk client
6856  *	from	- Buffer with data
6857  *	to	- Buffer where data is to be copied to
6858  *	mode	- flags passed to ioctl
6859  *	dir	- direction of copy (in or out)
6860  *
6861  * Return Code:
6862  *	0	- Success
6863  *	ENXIO	- Invalid buffer passed in
6864  *	EFAULT	- ddi_copyin of data failed
6865  */
6866 static int
6867 vdc_set_geom_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
6868 {
6869 	_NOTE(ARGUNUSED(vdc))
6870 
6871 	vd_geom_t	vdgeom;
6872 	void		*tmp_mem = NULL;
6873 	int		copy_len = sizeof (struct dk_geom);
6874 	int		rv = 0;
6875 
6876 	if (dir != VD_COPYIN)
6877 		return (0);	/* nothing to do */
6878 
6879 	if ((from == NULL) || (to == NULL))
6880 		return (ENXIO);
6881 
6882 	tmp_mem = kmem_alloc(copy_len, KM_SLEEP);
6883 
6884 	rv = ddi_copyin(from, tmp_mem, copy_len, mode);
6885 	if (rv != 0) {
6886 		kmem_free(tmp_mem, copy_len);
6887 		return (EFAULT);
6888 	}
6889 	DK_GEOM2VD_GEOM((struct dk_geom *)tmp_mem, &vdgeom);
6890 	bcopy(&vdgeom, to, sizeof (vdgeom));
6891 	kmem_free(tmp_mem, copy_len);
6892 
6893 	return (0);
6894 }
6895 
6896 static int
6897 vdc_get_efi_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
6898 {
6899 	_NOTE(ARGUNUSED(vdc))
6900 
6901 	vd_efi_t	*vd_efi;
6902 	dk_efi_t	dk_efi;
6903 	int		rv = 0;
6904 	void		*uaddr;
6905 
6906 	if ((from == NULL) || (to == NULL))
6907 		return (ENXIO);
6908 
6909 	if (dir == VD_COPYIN) {
6910 
6911 		vd_efi = (vd_efi_t *)to;
6912 
6913 		rv = ddi_copyin(from, &dk_efi, sizeof (dk_efi_t), mode);
6914 		if (rv != 0)
6915 			return (EFAULT);
6916 
6917 		vd_efi->lba = dk_efi.dki_lba;
6918 		vd_efi->length = dk_efi.dki_length;
6919 		bzero(vd_efi->data, vd_efi->length);
6920 
6921 	} else {
6922 
6923 		rv = ddi_copyin(to, &dk_efi, sizeof (dk_efi_t), mode);
6924 		if (rv != 0)
6925 			return (EFAULT);
6926 
6927 		uaddr = dk_efi.dki_data;
6928 
6929 		dk_efi.dki_data = kmem_alloc(dk_efi.dki_length, KM_SLEEP);
6930 
6931 		VD_EFI2DK_EFI((vd_efi_t *)from, &dk_efi);
6932 
6933 		rv = ddi_copyout(dk_efi.dki_data, uaddr, dk_efi.dki_length,
6934 		    mode);
6935 		if (rv != 0)
6936 			return (EFAULT);
6937 
6938 		kmem_free(dk_efi.dki_data, dk_efi.dki_length);
6939 	}
6940 
6941 	return (0);
6942 }
6943 
6944 static int
6945 vdc_set_efi_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
6946 {
6947 	_NOTE(ARGUNUSED(vdc))
6948 
6949 	dk_efi_t	dk_efi;
6950 	void		*uaddr;
6951 
6952 	if (dir == VD_COPYOUT) {
6953 		/*
6954 		 * The disk label may have changed. Revalidate the disk
6955 		 * geometry. This will also update the device nodes and
6956 		 * properties.
6957 		 */
6958 		vdc_validate(vdc);
6959 		return (0);
6960 	}
6961 
6962 	if ((from == NULL) || (to == NULL))
6963 		return (ENXIO);
6964 
6965 	if (ddi_copyin(from, &dk_efi, sizeof (dk_efi_t), mode) != 0)
6966 		return (EFAULT);
6967 
6968 	uaddr = dk_efi.dki_data;
6969 
6970 	dk_efi.dki_data = kmem_alloc(dk_efi.dki_length, KM_SLEEP);
6971 
6972 	if (ddi_copyin(uaddr, dk_efi.dki_data, dk_efi.dki_length, mode) != 0)
6973 		return (EFAULT);
6974 
6975 	DK_EFI2VD_EFI(&dk_efi, (vd_efi_t *)to);
6976 
6977 	kmem_free(dk_efi.dki_data, dk_efi.dki_length);
6978 
6979 	return (0);
6980 }
6981 
6982 
6983 /* -------------------------------------------------------------------------- */
6984 
6985 /*
6986  * Function:
6987  *	vdc_create_fake_geometry()
6988  *
6989  * Description:
6990  *	This routine fakes up the disk info needed for some DKIO ioctls such
6991  *	as DKIOCINFO and DKIOCGMEDIAINFO [just like lofi(7D) and ramdisk(7D) do]
6992  *
6993  *	Note: This function must not be called until the vDisk attributes have
6994  *	been exchanged as part of the handshake with the vDisk server.
6995  *
6996  * Arguments:
6997  *	vdc	- soft state pointer for this instance of the device driver.
6998  *
6999  * Return Code:
7000  *	none.
7001  */
7002 static void
7003 vdc_create_fake_geometry(vdc_t *vdc)
7004 {
7005 	ASSERT(vdc != NULL);
7006 	ASSERT(vdc->max_xfer_sz != 0);
7007 
7008 	/*
7009 	 * DKIOCINFO support
7010 	 */
7011 	if (vdc->cinfo == NULL)
7012 		vdc->cinfo = kmem_zalloc(sizeof (struct dk_cinfo), KM_SLEEP);
7013 
7014 	(void) strcpy(vdc->cinfo->dki_cname, VDC_DRIVER_NAME);
7015 	(void) strcpy(vdc->cinfo->dki_dname, VDC_DRIVER_NAME);
7016 	/* max_xfer_sz is #blocks so we don't need to divide by DEV_BSIZE */
7017 	vdc->cinfo->dki_maxtransfer = vdc->max_xfer_sz;
7018 
7019 	/*
7020 	 * We set the controller type to DKC_SCSI_CCS only if the VD_OP_SCSICMD
7021 	 * operation is supported, otherwise the controller type is DKC_DIRECT.
7022 	 * Version 1.0 does not support the VD_OP_SCSICMD operation, so the
7023 	 * controller type is always DKC_DIRECT in that case.
7024 	 *
7025 	 * If the virtual disk is backed by a physical CD/DVD device or
7026 	 * an ISO image, modify the controller type to indicate this
7027 	 */
7028 	switch (vdc->vdisk_media) {
7029 	case VD_MEDIA_CD:
7030 	case VD_MEDIA_DVD:
7031 		vdc->cinfo->dki_ctype = DKC_CDROM;
7032 		break;
7033 	case VD_MEDIA_FIXED:
7034 		if (VD_OP_SUPPORTED(vdc->operations, VD_OP_SCSICMD))
7035 			vdc->cinfo->dki_ctype = DKC_SCSI_CCS;
7036 		else
7037 			vdc->cinfo->dki_ctype = DKC_DIRECT;
7038 		break;
7039 	default:
7040 		/* in the case of v1.0 we default to a fixed disk */
7041 		vdc->cinfo->dki_ctype = DKC_DIRECT;
7042 		break;
7043 	}
7044 	vdc->cinfo->dki_flags = DKI_FMTVOL;
7045 	vdc->cinfo->dki_cnum = 0;
7046 	vdc->cinfo->dki_addr = 0;
7047 	vdc->cinfo->dki_space = 0;
7048 	vdc->cinfo->dki_prio = 0;
7049 	vdc->cinfo->dki_vec = 0;
7050 	vdc->cinfo->dki_unit = vdc->instance;
7051 	vdc->cinfo->dki_slave = 0;
7052 	/*
7053 	 * The partition number will be created on the fly depending on the
7054 	 * actual slice (i.e. minor node) that is used to request the data.
7055 	 */
7056 	vdc->cinfo->dki_partition = 0;
7057 
7058 	/*
7059 	 * DKIOCGMEDIAINFO support
7060 	 */
7061 	if (vdc->minfo == NULL)
7062 		vdc->minfo = kmem_zalloc(sizeof (struct dk_minfo), KM_SLEEP);
7063 
7064 	if (vio_ver_is_supported(vdc->ver, 1, 1)) {
7065 		vdc->minfo->dki_media_type =
7066 		    VD_MEDIATYPE2DK_MEDIATYPE(vdc->vdisk_media);
7067 	} else {
7068 		vdc->minfo->dki_media_type = DK_FIXED_DISK;
7069 	}
7070 
7071 	vdc->minfo->dki_capacity = vdc->vdisk_size;
7072 	vdc->minfo->dki_lbsize = vdc->block_size;
7073 }
7074 
7075 static ushort_t
7076 vdc_lbl2cksum(struct dk_label *label)
7077 {
7078 	int	count;
7079 	ushort_t sum, *sp;
7080 
7081 	count =	(sizeof (struct dk_label)) / (sizeof (short)) - 1;
7082 	sp = (ushort_t *)label;
7083 	sum = 0;
7084 	while (count--) {
7085 		sum ^= *sp++;
7086 	}
7087 
7088 	return (sum);
7089 }
7090 
7091 /*
7092  * Function:
7093  *	vdc_validate_geometry
7094  *
7095  * Description:
7096  *	This routine discovers the label and geometry of the disk. It stores
7097  *	the disk label and related information in the vdc structure. If it
7098  *	fails to validate the geometry or to discover the disk label then
7099  *	the label is marked as unknown (VD_DISK_LABEL_UNK).
7100  *
7101  * Arguments:
7102  *	vdc	- soft state pointer for this instance of the device driver.
7103  *
7104  * Return Code:
7105  *	0	- success.
7106  *	EINVAL	- unknown disk label.
7107  *	ENOTSUP	- geometry not applicable (EFI label).
7108  *	EIO	- error accessing the disk.
7109  */
7110 static int
7111 vdc_validate_geometry(vdc_t *vdc)
7112 {
7113 	buf_t	*buf;	/* BREAD requests need to be in a buf_t structure */
7114 	dev_t	dev;
7115 	int	rv, rval;
7116 	struct dk_label label;
7117 	struct dk_geom geom;
7118 	struct vtoc vtoc;
7119 
7120 	ASSERT(vdc != NULL);
7121 	ASSERT(vdc->vtoc != NULL && vdc->geom != NULL);
7122 	ASSERT(MUTEX_HELD(&vdc->lock));
7123 
7124 	mutex_exit(&vdc->lock);
7125 
7126 	dev = makedevice(ddi_driver_major(vdc->dip),
7127 	    VD_MAKE_DEV(vdc->instance, 0));
7128 
7129 	rv = vd_process_ioctl(dev, DKIOCGGEOM, (caddr_t)&geom, FKIOCTL, &rval);
7130 	if (rv == 0)
7131 		rv = vd_process_ioctl(dev, DKIOCGVTOC, (caddr_t)&vtoc,
7132 		    FKIOCTL, &rval);
7133 
7134 	if (rv == ENOTSUP) {
7135 		/*
7136 		 * If the device does not support VTOC then we try
7137 		 * to read an EFI label.
7138 		 */
7139 		struct dk_gpt *efi;
7140 		size_t efi_len;
7141 
7142 		rv = vdc_efi_alloc_and_read(dev, &efi, &efi_len);
7143 
7144 		if (rv) {
7145 			DMSG(vdc, 0, "[%d] Failed to get EFI (err=%d)",
7146 			    vdc->instance, rv);
7147 			mutex_enter(&vdc->lock);
7148 			vdc_store_label_unk(vdc);
7149 			return (EIO);
7150 		}
7151 
7152 		mutex_enter(&vdc->lock);
7153 		vdc_store_label_efi(vdc, efi);
7154 		vd_efi_free(efi, efi_len);
7155 		return (ENOTSUP);
7156 	}
7157 
7158 	if (rv != 0) {
7159 		DMSG(vdc, 0, "[%d] Failed to get VTOC (err=%d)",
7160 		    vdc->instance, rv);
7161 		mutex_enter(&vdc->lock);
7162 		vdc_store_label_unk(vdc);
7163 		if (rv != EINVAL)
7164 			rv = EIO;
7165 		return (rv);
7166 	}
7167 
7168 	/* check that geometry and vtoc are valid */
7169 	if (geom.dkg_nhead == 0 || geom.dkg_nsect == 0 ||
7170 	    vtoc.v_sanity != VTOC_SANE) {
7171 		mutex_enter(&vdc->lock);
7172 		vdc_store_label_unk(vdc);
7173 		return (EINVAL);
7174 	}
7175 
7176 	/*
7177 	 * We have a disk and a valid VTOC. However this does not mean
7178 	 * that the disk currently have a VTOC label. The returned VTOC may
7179 	 * be a default VTOC to be used for configuring the disk (this is
7180 	 * what is done for disk image). So we read the label from the
7181 	 * beginning of the disk to ensure we really have a VTOC label.
7182 	 *
7183 	 * FUTURE: This could be the default way for reading the VTOC
7184 	 * from the disk as opposed to sending the VD_OP_GET_VTOC
7185 	 * to the server. This will be the default if vdc is implemented
7186 	 * ontop of cmlb.
7187 	 */
7188 
7189 	/*
7190 	 * Single slice disk does not support read using an absolute disk
7191 	 * offset so we just rely on the DKIOCGVTOC ioctl in that case.
7192 	 */
7193 	if (vdc->vdisk_type == VD_DISK_TYPE_SLICE) {
7194 		mutex_enter(&vdc->lock);
7195 		if (vtoc.v_nparts != 1) {
7196 			vdc_store_label_unk(vdc);
7197 			return (EINVAL);
7198 		}
7199 		vdc_store_label_vtoc(vdc, &geom, &vtoc);
7200 		return (0);
7201 	}
7202 
7203 	if (vtoc.v_nparts != V_NUMPAR) {
7204 		mutex_enter(&vdc->lock);
7205 		vdc_store_label_unk(vdc);
7206 		return (EINVAL);
7207 	}
7208 
7209 	/*
7210 	 * Read disk label from start of disk
7211 	 */
7212 	buf = kmem_alloc(sizeof (buf_t), KM_SLEEP);
7213 	bioinit(buf);
7214 	buf->b_un.b_addr = (caddr_t)&label;
7215 	buf->b_bcount = DK_LABEL_SIZE;
7216 	buf->b_flags = B_BUSY | B_READ;
7217 	buf->b_dev = cmpdev(dev);
7218 	rv = vdc_send_request(vdc, VD_OP_BREAD, (caddr_t)&label,
7219 	    DK_LABEL_SIZE, VD_SLICE_NONE, 0, CB_STRATEGY, buf, VIO_read_dir);
7220 	if (rv) {
7221 		DMSG(vdc, 1, "[%d] Failed to read disk block 0\n",
7222 		    vdc->instance);
7223 	} else {
7224 		rv = biowait(buf);
7225 		biofini(buf);
7226 	}
7227 	kmem_free(buf, sizeof (buf_t));
7228 
7229 	if (rv != 0 || label.dkl_magic != DKL_MAGIC ||
7230 	    label.dkl_cksum != vdc_lbl2cksum(&label)) {
7231 		DMSG(vdc, 1, "[%d] Got VTOC with invalid label\n",
7232 		    vdc->instance);
7233 		mutex_enter(&vdc->lock);
7234 		vdc_store_label_unk(vdc);
7235 		return (EINVAL);
7236 	}
7237 
7238 	mutex_enter(&vdc->lock);
7239 	vdc_store_label_vtoc(vdc, &geom, &vtoc);
7240 	return (0);
7241 }
7242 
7243 /*
7244  * Function:
7245  *	vdc_validate
7246  *
7247  * Description:
7248  *	This routine discovers the label of the disk and create the
7249  *	appropriate device nodes if the label has changed.
7250  *
7251  * Arguments:
7252  *	vdc	- soft state pointer for this instance of the device driver.
7253  *
7254  * Return Code:
7255  *	none.
7256  */
7257 static void
7258 vdc_validate(vdc_t *vdc)
7259 {
7260 	vd_disk_label_t old_label;
7261 	struct vtoc old_vtoc;
7262 	int rv;
7263 
7264 	ASSERT(!MUTEX_HELD(&vdc->lock));
7265 
7266 	mutex_enter(&vdc->lock);
7267 
7268 	/* save the current label and vtoc */
7269 	old_label = vdc->vdisk_label;
7270 	bcopy(vdc->vtoc, &old_vtoc, sizeof (struct vtoc));
7271 
7272 	/* check the geometry */
7273 	(void) vdc_validate_geometry(vdc);
7274 
7275 	/* if the disk label has changed, update device nodes */
7276 	if (vdc->vdisk_label != old_label) {
7277 
7278 		if (vdc->vdisk_label == VD_DISK_LABEL_EFI)
7279 			rv = vdc_create_device_nodes_efi(vdc);
7280 		else
7281 			rv = vdc_create_device_nodes_vtoc(vdc);
7282 
7283 		if (rv != 0) {
7284 			DMSG(vdc, 0, "![%d] Failed to update device nodes",
7285 			    vdc->instance);
7286 		}
7287 	}
7288 
7289 	/* if the vtoc has changed, update device nodes properties */
7290 	if (bcmp(vdc->vtoc, &old_vtoc, sizeof (struct vtoc)) != 0) {
7291 
7292 		if (vdc_create_device_nodes_props(vdc) != 0) {
7293 			DMSG(vdc, 0, "![%d] Failed to update device nodes"
7294 			    " properties", vdc->instance);
7295 		}
7296 	}
7297 
7298 	mutex_exit(&vdc->lock);
7299 }
7300 
7301 static void
7302 vdc_validate_task(void *arg)
7303 {
7304 	vdc_t *vdc = (vdc_t *)arg;
7305 
7306 	vdc_validate(vdc);
7307 
7308 	mutex_enter(&vdc->lock);
7309 	ASSERT(vdc->validate_pending > 0);
7310 	vdc->validate_pending--;
7311 	mutex_exit(&vdc->lock);
7312 }
7313 
7314 /*
7315  * Function:
7316  *	vdc_setup_devid()
7317  *
7318  * Description:
7319  *	This routine discovers the devid of a vDisk. It requests the devid of
7320  *	the underlying device from the vDisk server, builds an encapsulated
7321  *	devid based on the retrieved devid and registers that new devid to
7322  *	the vDisk.
7323  *
7324  * Arguments:
7325  *	vdc	- soft state pointer for this instance of the device driver.
7326  *
7327  * Return Code:
7328  *	0	- A devid was succesfully registered for the vDisk
7329  */
7330 static int
7331 vdc_setup_devid(vdc_t *vdc)
7332 {
7333 	int rv;
7334 	vd_devid_t *vd_devid;
7335 	size_t bufsize, bufid_len;
7336 
7337 	/*
7338 	 * At first sight, we don't know the size of the devid that the
7339 	 * server will return but this size will be encoded into the
7340 	 * reply. So we do a first request using a default size then we
7341 	 * check if this size was large enough. If not then we do a second
7342 	 * request with the correct size returned by the server. Note that
7343 	 * ldc requires size to be 8-byte aligned.
7344 	 */
7345 	bufsize = P2ROUNDUP(VD_DEVID_SIZE(VD_DEVID_DEFAULT_LEN),
7346 	    sizeof (uint64_t));
7347 	vd_devid = kmem_zalloc(bufsize, KM_SLEEP);
7348 	bufid_len = bufsize - sizeof (vd_efi_t) - 1;
7349 
7350 	rv = vdc_do_sync_op(vdc, VD_OP_GET_DEVID, (caddr_t)vd_devid,
7351 	    bufsize, 0, 0, CB_SYNC, 0, VIO_both_dir, B_TRUE);
7352 
7353 	DMSG(vdc, 2, "sync_op returned %d\n", rv);
7354 
7355 	if (rv) {
7356 		kmem_free(vd_devid, bufsize);
7357 		return (rv);
7358 	}
7359 
7360 	if (vd_devid->length > bufid_len) {
7361 		/*
7362 		 * The returned devid is larger than the buffer used. Try again
7363 		 * with a buffer with the right size.
7364 		 */
7365 		kmem_free(vd_devid, bufsize);
7366 		bufsize = P2ROUNDUP(VD_DEVID_SIZE(vd_devid->length),
7367 		    sizeof (uint64_t));
7368 		vd_devid = kmem_zalloc(bufsize, KM_SLEEP);
7369 		bufid_len = bufsize - sizeof (vd_efi_t) - 1;
7370 
7371 		rv = vdc_do_sync_op(vdc, VD_OP_GET_DEVID,
7372 		    (caddr_t)vd_devid, bufsize, 0, 0, CB_SYNC, 0,
7373 		    VIO_both_dir, B_TRUE);
7374 
7375 		if (rv) {
7376 			kmem_free(vd_devid, bufsize);
7377 			return (rv);
7378 		}
7379 	}
7380 
7381 	/*
7382 	 * The virtual disk should have the same device id as the one associated
7383 	 * with the physical disk it is mapped on, otherwise sharing a disk
7384 	 * between a LDom and a non-LDom may not work (for example for a shared
7385 	 * SVM disk set).
7386 	 *
7387 	 * The DDI framework does not allow creating a device id with any
7388 	 * type so we first create a device id of type DEVID_ENCAP and then
7389 	 * we restore the orignal type of the physical device.
7390 	 */
7391 
7392 	DMSG(vdc, 2, ": devid length = %d\n", vd_devid->length);
7393 
7394 	/* build an encapsulated devid based on the returned devid */
7395 	if (ddi_devid_init(vdc->dip, DEVID_ENCAP, vd_devid->length,
7396 	    vd_devid->id, &vdc->devid) != DDI_SUCCESS) {
7397 		DMSG(vdc, 1, "[%d] Fail to created devid\n", vdc->instance);
7398 		kmem_free(vd_devid, bufsize);
7399 		return (1);
7400 	}
7401 
7402 	DEVID_FORMTYPE((impl_devid_t *)vdc->devid, vd_devid->type);
7403 
7404 	ASSERT(ddi_devid_valid(vdc->devid) == DDI_SUCCESS);
7405 
7406 	kmem_free(vd_devid, bufsize);
7407 
7408 	if (ddi_devid_register(vdc->dip, vdc->devid) != DDI_SUCCESS) {
7409 		DMSG(vdc, 1, "[%d] Fail to register devid\n", vdc->instance);
7410 		return (1);
7411 	}
7412 
7413 	return (0);
7414 }
7415 
7416 static void
7417 vdc_store_label_efi(vdc_t *vdc, struct dk_gpt *efi)
7418 {
7419 	struct vtoc *vtoc = vdc->vtoc;
7420 
7421 	ASSERT(MUTEX_HELD(&vdc->lock));
7422 
7423 	vdc->vdisk_label = VD_DISK_LABEL_EFI;
7424 	bzero(vdc->geom, sizeof (struct dk_geom));
7425 	vd_efi_to_vtoc(efi, vtoc);
7426 	if (vdc->vdisk_type == VD_DISK_TYPE_SLICE) {
7427 		/*
7428 		 * vd_efi_to_vtoc() will store information about the EFI Sun
7429 		 * reserved partition (representing the entire disk) into
7430 		 * partition 7. However single-slice device will only have
7431 		 * that single partition and the vdc driver expects to find
7432 		 * information about that partition in slice 0. So we need
7433 		 * to copy information from slice 7 to slice 0.
7434 		 */
7435 		vtoc->v_part[0].p_tag = vtoc->v_part[VD_EFI_WD_SLICE].p_tag;
7436 		vtoc->v_part[0].p_flag = vtoc->v_part[VD_EFI_WD_SLICE].p_flag;
7437 		vtoc->v_part[0].p_start = vtoc->v_part[VD_EFI_WD_SLICE].p_start;
7438 		vtoc->v_part[0].p_size =  vtoc->v_part[VD_EFI_WD_SLICE].p_size;
7439 	}
7440 }
7441 
7442 static void
7443 vdc_store_label_vtoc(vdc_t *vdc, struct dk_geom *geom, struct vtoc *vtoc)
7444 {
7445 	ASSERT(MUTEX_HELD(&vdc->lock));
7446 
7447 	vdc->vdisk_label = VD_DISK_LABEL_VTOC;
7448 	bcopy(vtoc, vdc->vtoc, sizeof (struct vtoc));
7449 	bcopy(geom, vdc->geom, sizeof (struct dk_geom));
7450 }
7451 
7452 static void
7453 vdc_store_label_unk(vdc_t *vdc)
7454 {
7455 	ASSERT(MUTEX_HELD(&vdc->lock));
7456 
7457 	vdc->vdisk_label = VD_DISK_LABEL_UNK;
7458 	bzero(vdc->vtoc, sizeof (struct vtoc));
7459 	bzero(vdc->geom, sizeof (struct dk_geom));
7460 }
7461