xref: /titanic_41/usr/src/uts/sun4v/io/vdc.c (revision 4bd2082ff2d009263265d7de938de336894b6009)
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/vtoc.h>
79 #include <sys/archsystm.h>
80 #include <sys/sysmacros.h>
81 
82 #include <sys/cdio.h>
83 #include <sys/dktp/fdisk.h>
84 #include <sys/scsi/generic/sense.h>
85 #include <sys/scsi/impl/uscsi.h>	/* Needed for defn of USCSICMD ioctl */
86 
87 #include <sys/ldoms.h>
88 #include <sys/ldc.h>
89 #include <sys/vio_common.h>
90 #include <sys/vio_mailbox.h>
91 #include <sys/vdsk_common.h>
92 #include <sys/vdsk_mailbox.h>
93 #include <sys/vdc.h>
94 
95 /*
96  * function prototypes
97  */
98 
99 /* standard driver functions */
100 static int	vdc_open(dev_t *dev, int flag, int otyp, cred_t *cred);
101 static int	vdc_close(dev_t dev, int flag, int otyp, cred_t *cred);
102 static int	vdc_strategy(struct buf *buf);
103 static int	vdc_print(dev_t dev, char *str);
104 static int	vdc_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk);
105 static int	vdc_read(dev_t dev, struct uio *uio, cred_t *cred);
106 static int	vdc_write(dev_t dev, struct uio *uio, cred_t *cred);
107 static int	vdc_ioctl(dev_t dev, int cmd, intptr_t arg, int mode,
108 			cred_t *credp, int *rvalp);
109 static int	vdc_aread(dev_t dev, struct aio_req *aio, cred_t *cred);
110 static int	vdc_awrite(dev_t dev, struct aio_req *aio, cred_t *cred);
111 
112 static int	vdc_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd,
113 			void *arg, void **resultp);
114 static int	vdc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
115 static int	vdc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);
116 
117 /* setup */
118 static void	vdc_min(struct buf *bufp);
119 static int	vdc_send(vdc_t *vdc, caddr_t pkt, size_t *msglen);
120 static int	vdc_do_ldc_init(vdc_t *vdc);
121 static int	vdc_start_ldc_connection(vdc_t *vdc);
122 static int	vdc_create_device_nodes(vdc_t *vdc);
123 static int	vdc_create_device_nodes_efi(vdc_t *vdc);
124 static int	vdc_create_device_nodes_vtoc(vdc_t *vdc);
125 static int	vdc_create_device_nodes_props(vdc_t *vdc);
126 static int	vdc_get_ldc_id(dev_info_t *dip, uint64_t *ldc_id);
127 static int	vdc_do_ldc_up(vdc_t *vdc);
128 static void	vdc_terminate_ldc(vdc_t *vdc);
129 static int	vdc_init_descriptor_ring(vdc_t *vdc);
130 static void	vdc_destroy_descriptor_ring(vdc_t *vdc);
131 static int	vdc_setup_devid(vdc_t *vdc);
132 static void	vdc_store_efi(vdc_t *vdc, struct dk_gpt *efi);
133 
134 /* handshake with vds */
135 static int		vdc_init_ver_negotiation(vdc_t *vdc, vio_ver_t ver);
136 static int		vdc_ver_negotiation(vdc_t *vdcp);
137 static int		vdc_init_attr_negotiation(vdc_t *vdc);
138 static int		vdc_attr_negotiation(vdc_t *vdcp);
139 static int		vdc_init_dring_negotiate(vdc_t *vdc);
140 static int		vdc_dring_negotiation(vdc_t *vdcp);
141 static int		vdc_send_rdx(vdc_t *vdcp);
142 static int		vdc_rdx_exchange(vdc_t *vdcp);
143 static boolean_t	vdc_is_supported_version(vio_ver_msg_t *ver_msg);
144 
145 /* processing incoming messages from vDisk server */
146 static void	vdc_process_msg_thread(vdc_t *vdc);
147 static int	vdc_recv(vdc_t *vdc, vio_msg_t *msgp, size_t *nbytesp);
148 
149 static uint_t	vdc_handle_cb(uint64_t event, caddr_t arg);
150 static int	vdc_process_data_msg(vdc_t *vdc, vio_msg_t *msg);
151 static int	vdc_process_err_msg(vdc_t *vdc, vio_msg_t msg);
152 static int	vdc_handle_ver_msg(vdc_t *vdc, vio_ver_msg_t *ver_msg);
153 static int	vdc_handle_attr_msg(vdc_t *vdc, vd_attr_msg_t *attr_msg);
154 static int	vdc_handle_dring_reg_msg(vdc_t *vdc, vio_dring_reg_msg_t *msg);
155 static int 	vdc_send_request(vdc_t *vdcp, int operation,
156 		    caddr_t addr, size_t nbytes, int slice, diskaddr_t offset,
157 		    int cb_type, void *cb_arg, vio_desc_direction_t dir);
158 static int	vdc_map_to_shared_dring(vdc_t *vdcp, int idx);
159 static int 	vdc_populate_descriptor(vdc_t *vdcp, int operation,
160 		    caddr_t addr, size_t nbytes, int slice, diskaddr_t offset,
161 		    int cb_type, void *cb_arg, vio_desc_direction_t dir);
162 static int 	vdc_do_sync_op(vdc_t *vdcp, int operation,
163 		    caddr_t addr, size_t nbytes, int slice, diskaddr_t offset,
164 		    int cb_type, void *cb_arg, vio_desc_direction_t dir);
165 
166 static int	vdc_wait_for_response(vdc_t *vdcp, vio_msg_t *msgp);
167 static int	vdc_drain_response(vdc_t *vdcp);
168 static int	vdc_depopulate_descriptor(vdc_t *vdc, uint_t idx);
169 static int	vdc_populate_mem_hdl(vdc_t *vdcp, vdc_local_desc_t *ldep);
170 static int	vdc_verify_seq_num(vdc_t *vdc, vio_dring_msg_t *dring_msg);
171 
172 /* dkio */
173 static int	vd_process_ioctl(dev_t dev, int cmd, caddr_t arg, int mode);
174 static int	vdc_create_fake_geometry(vdc_t *vdc);
175 static int	vdc_setup_disk_layout(vdc_t *vdc);
176 static int	vdc_null_copy_func(vdc_t *vdc, void *from, void *to,
177 		    int mode, int dir);
178 static int	vdc_get_wce_convert(vdc_t *vdc, void *from, void *to,
179 		    int mode, int dir);
180 static int	vdc_set_wce_convert(vdc_t *vdc, void *from, void *to,
181 		    int mode, int dir);
182 static int	vdc_get_vtoc_convert(vdc_t *vdc, void *from, void *to,
183 		    int mode, int dir);
184 static int	vdc_set_vtoc_convert(vdc_t *vdc, void *from, void *to,
185 		    int mode, int dir);
186 static int	vdc_get_geom_convert(vdc_t *vdc, void *from, void *to,
187 		    int mode, int dir);
188 static int	vdc_set_geom_convert(vdc_t *vdc, void *from, void *to,
189 		    int mode, int dir);
190 static int	vdc_uscsicmd_convert(vdc_t *vdc, void *from, void *to,
191 		    int mode, int dir);
192 static int	vdc_get_efi_convert(vdc_t *vdc, void *from, void *to,
193 		    int mode, int dir);
194 static int	vdc_set_efi_convert(vdc_t *vdc, void *from, void *to,
195 		    int mode, int dir);
196 
197 /*
198  * Module variables
199  */
200 
201 /*
202  * Tunable variables to control how long vdc waits before timing out on
203  * various operations
204  */
205 static int	vdc_retries = 10;
206 static int	vdc_hshake_retries = 3;
207 
208 /* calculated from 'vdc_usec_timeout' during attach */
209 static uint64_t	vdc_hz_timeout;				/* units: Hz */
210 static uint64_t	vdc_usec_timeout = 30 * MICROSEC;	/* 30s units: ns */
211 
212 static uint64_t vdc_hz_min_ldc_delay;
213 static uint64_t vdc_min_timeout_ldc = 1 * MILLISEC;
214 static uint64_t vdc_hz_max_ldc_delay;
215 static uint64_t vdc_max_timeout_ldc = 100 * MILLISEC;
216 
217 static uint64_t vdc_ldc_read_init_delay = 1 * MILLISEC;
218 static uint64_t vdc_ldc_read_max_delay = 100 * MILLISEC;
219 
220 /* values for dumping - need to run in a tighter loop */
221 static uint64_t	vdc_usec_timeout_dump = 100 * MILLISEC;	/* 0.1s units: ns */
222 static int	vdc_dump_retries = 100;
223 
224 /* Count of the number of vdc instances attached */
225 static volatile uint32_t	vdc_instance_count = 0;
226 
227 /* Soft state pointer */
228 static void	*vdc_state;
229 
230 /*
231  * Controlling the verbosity of the error/debug messages
232  *
233  * vdc_msglevel - controls level of messages
234  * vdc_matchinst - 64-bit variable where each bit corresponds
235  *                 to the vdc instance the vdc_msglevel applies.
236  */
237 int		vdc_msglevel = 0x0;
238 uint64_t	vdc_matchinst = 0ull;
239 
240 /*
241  * Supported vDisk protocol version pairs.
242  *
243  * The first array entry is the latest and preferred version.
244  */
245 static const vio_ver_t	vdc_version[] = {{1, 0}};
246 
247 static struct cb_ops vdc_cb_ops = {
248 	vdc_open,	/* cb_open */
249 	vdc_close,	/* cb_close */
250 	vdc_strategy,	/* cb_strategy */
251 	vdc_print,	/* cb_print */
252 	vdc_dump,	/* cb_dump */
253 	vdc_read,	/* cb_read */
254 	vdc_write,	/* cb_write */
255 	vdc_ioctl,	/* cb_ioctl */
256 	nodev,		/* cb_devmap */
257 	nodev,		/* cb_mmap */
258 	nodev,		/* cb_segmap */
259 	nochpoll,	/* cb_chpoll */
260 	ddi_prop_op,	/* cb_prop_op */
261 	NULL,		/* cb_str */
262 	D_MP | D_64BIT,	/* cb_flag */
263 	CB_REV,		/* cb_rev */
264 	vdc_aread,	/* cb_aread */
265 	vdc_awrite	/* cb_awrite */
266 };
267 
268 static struct dev_ops vdc_ops = {
269 	DEVO_REV,	/* devo_rev */
270 	0,		/* devo_refcnt */
271 	vdc_getinfo,	/* devo_getinfo */
272 	nulldev,	/* devo_identify */
273 	nulldev,	/* devo_probe */
274 	vdc_attach,	/* devo_attach */
275 	vdc_detach,	/* devo_detach */
276 	nodev,		/* devo_reset */
277 	&vdc_cb_ops,	/* devo_cb_ops */
278 	NULL,		/* devo_bus_ops */
279 	nulldev		/* devo_power */
280 };
281 
282 static struct modldrv modldrv = {
283 	&mod_driverops,
284 	"virtual disk client %I%",
285 	&vdc_ops,
286 };
287 
288 static struct modlinkage modlinkage = {
289 	MODREV_1,
290 	&modldrv,
291 	NULL
292 };
293 
294 /* -------------------------------------------------------------------------- */
295 
296 /*
297  * Device Driver housekeeping and setup
298  */
299 
300 int
301 _init(void)
302 {
303 	int	status;
304 
305 	if ((status = ddi_soft_state_init(&vdc_state, sizeof (vdc_t), 1)) != 0)
306 		return (status);
307 	if ((status = mod_install(&modlinkage)) != 0)
308 		ddi_soft_state_fini(&vdc_state);
309 	vdc_efi_init(vd_process_ioctl);
310 	return (status);
311 }
312 
313 int
314 _info(struct modinfo *modinfop)
315 {
316 	return (mod_info(&modlinkage, modinfop));
317 }
318 
319 int
320 _fini(void)
321 {
322 	int	status;
323 
324 	if ((status = mod_remove(&modlinkage)) != 0)
325 		return (status);
326 	vdc_efi_fini();
327 	ddi_soft_state_fini(&vdc_state);
328 	return (0);
329 }
330 
331 static int
332 vdc_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd,  void *arg, void **resultp)
333 {
334 	_NOTE(ARGUNUSED(dip))
335 
336 	int	instance = VDCUNIT((dev_t)arg);
337 	vdc_t	*vdc = NULL;
338 
339 	switch (cmd) {
340 	case DDI_INFO_DEVT2DEVINFO:
341 		if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
342 			*resultp = NULL;
343 			return (DDI_FAILURE);
344 		}
345 		*resultp = vdc->dip;
346 		return (DDI_SUCCESS);
347 	case DDI_INFO_DEVT2INSTANCE:
348 		*resultp = (void *)(uintptr_t)instance;
349 		return (DDI_SUCCESS);
350 	default:
351 		*resultp = NULL;
352 		return (DDI_FAILURE);
353 	}
354 }
355 
356 static int
357 vdc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
358 {
359 	int	instance;
360 	int	rv;
361 	vdc_t	*vdc = NULL;
362 
363 	switch (cmd) {
364 	case DDI_DETACH:
365 		/* the real work happens below */
366 		break;
367 	case DDI_SUSPEND:
368 		/* nothing to do for this non-device */
369 		return (DDI_SUCCESS);
370 	default:
371 		return (DDI_FAILURE);
372 	}
373 
374 	ASSERT(cmd == DDI_DETACH);
375 	instance = ddi_get_instance(dip);
376 	DMSGX(1, "[%d] Entered\n", instance);
377 
378 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
379 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
380 		return (DDI_FAILURE);
381 	}
382 
383 	if (vdc->open_count) {
384 		DMSG(vdc, 0, "[%d] Cannot detach: device is open", instance);
385 		return (DDI_FAILURE);
386 	}
387 
388 	DMSG(vdc, 0, "[%d] proceeding...\n", instance);
389 
390 	/* mark instance as detaching */
391 	vdc->lifecycle	= VDC_LC_DETACHING;
392 
393 	/*
394 	 * try and disable callbacks to prevent another handshake
395 	 */
396 	rv = ldc_set_cb_mode(vdc->ldc_handle, LDC_CB_DISABLE);
397 	DMSG(vdc, 0, "callback disabled (rv=%d)\n", rv);
398 
399 	if (vdc->initialized & VDC_THREAD) {
400 		mutex_enter(&vdc->read_lock);
401 		if ((vdc->read_state == VDC_READ_WAITING) ||
402 		    (vdc->read_state == VDC_READ_RESET)) {
403 			vdc->read_state = VDC_READ_RESET;
404 			cv_signal(&vdc->read_cv);
405 		}
406 
407 		mutex_exit(&vdc->read_lock);
408 
409 		/* wake up any thread waiting for connection to come online */
410 		mutex_enter(&vdc->lock);
411 		if (vdc->state == VDC_STATE_INIT_WAITING) {
412 			DMSG(vdc, 0,
413 			    "[%d] write reset - move to resetting state...\n",
414 			    instance);
415 			vdc->state = VDC_STATE_RESETTING;
416 			cv_signal(&vdc->initwait_cv);
417 		}
418 		mutex_exit(&vdc->lock);
419 
420 		/* now wait until state transitions to VDC_STATE_DETACH */
421 		thread_join(vdc->msg_proc_thr->t_did);
422 		ASSERT(vdc->state == VDC_STATE_DETACH);
423 		DMSG(vdc, 0, "[%d] Reset thread exit and join ..\n",
424 		    vdc->instance);
425 	}
426 
427 	mutex_enter(&vdc->lock);
428 
429 	if (vdc->initialized & VDC_DRING)
430 		vdc_destroy_descriptor_ring(vdc);
431 
432 	if (vdc->initialized & VDC_LDC)
433 		vdc_terminate_ldc(vdc);
434 
435 	mutex_exit(&vdc->lock);
436 
437 	if (vdc->initialized & VDC_MINOR) {
438 		ddi_prop_remove_all(dip);
439 		ddi_remove_minor_node(dip, NULL);
440 	}
441 
442 	if (vdc->initialized & VDC_LOCKS) {
443 		mutex_destroy(&vdc->lock);
444 		mutex_destroy(&vdc->read_lock);
445 		cv_destroy(&vdc->initwait_cv);
446 		cv_destroy(&vdc->dring_free_cv);
447 		cv_destroy(&vdc->membind_cv);
448 		cv_destroy(&vdc->sync_pending_cv);
449 		cv_destroy(&vdc->sync_blocked_cv);
450 		cv_destroy(&vdc->read_cv);
451 		cv_destroy(&vdc->running_cv);
452 	}
453 
454 	if (vdc->minfo)
455 		kmem_free(vdc->minfo, sizeof (struct dk_minfo));
456 
457 	if (vdc->cinfo)
458 		kmem_free(vdc->cinfo, sizeof (struct dk_cinfo));
459 
460 	if (vdc->vtoc)
461 		kmem_free(vdc->vtoc, sizeof (struct vtoc));
462 
463 	if (vdc->label)
464 		kmem_free(vdc->label, DK_LABEL_SIZE);
465 
466 	if (vdc->devid) {
467 		ddi_devid_unregister(dip);
468 		ddi_devid_free(vdc->devid);
469 	}
470 
471 	if (vdc->initialized & VDC_SOFT_STATE)
472 		ddi_soft_state_free(vdc_state, instance);
473 
474 	DMSG(vdc, 0, "[%d] End %p\n", instance, (void *)vdc);
475 
476 	return (DDI_SUCCESS);
477 }
478 
479 
480 static int
481 vdc_do_attach(dev_info_t *dip)
482 {
483 	int		instance;
484 	vdc_t		*vdc = NULL;
485 	int		status;
486 
487 	ASSERT(dip != NULL);
488 
489 	instance = ddi_get_instance(dip);
490 	if (ddi_soft_state_zalloc(vdc_state, instance) != DDI_SUCCESS) {
491 		cmn_err(CE_NOTE, "[%d] Couldn't alloc state structure",
492 		    instance);
493 		return (DDI_FAILURE);
494 	}
495 
496 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
497 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
498 		return (DDI_FAILURE);
499 	}
500 
501 	/*
502 	 * We assign the value to initialized in this case to zero out the
503 	 * variable and then set bits in it to indicate what has been done
504 	 */
505 	vdc->initialized = VDC_SOFT_STATE;
506 
507 	vdc_hz_timeout = drv_usectohz(vdc_usec_timeout);
508 
509 	vdc_hz_min_ldc_delay = drv_usectohz(vdc_min_timeout_ldc);
510 	vdc_hz_max_ldc_delay = drv_usectohz(vdc_max_timeout_ldc);
511 
512 	vdc->dip	= dip;
513 	vdc->instance	= instance;
514 	vdc->open_count	= 0;
515 	vdc->vdisk_type	= VD_DISK_TYPE_UNK;
516 	vdc->vdisk_label = VD_DISK_LABEL_UNK;
517 	vdc->state	= VDC_STATE_INIT;
518 	vdc->lifecycle	= VDC_LC_ATTACHING;
519 	vdc->ldc_state	= 0;
520 	vdc->session_id = 0;
521 	vdc->block_size = DEV_BSIZE;
522 	vdc->max_xfer_sz = maxphys / DEV_BSIZE;
523 
524 	vdc->vtoc = NULL;
525 	vdc->cinfo = NULL;
526 	vdc->minfo = NULL;
527 
528 	mutex_init(&vdc->lock, NULL, MUTEX_DRIVER, NULL);
529 	cv_init(&vdc->initwait_cv, NULL, CV_DRIVER, NULL);
530 	cv_init(&vdc->dring_free_cv, NULL, CV_DRIVER, NULL);
531 	cv_init(&vdc->membind_cv, NULL, CV_DRIVER, NULL);
532 	cv_init(&vdc->running_cv, NULL, CV_DRIVER, NULL);
533 
534 	vdc->threads_pending = 0;
535 	vdc->sync_op_pending = B_FALSE;
536 	vdc->sync_op_blocked = B_FALSE;
537 	cv_init(&vdc->sync_pending_cv, NULL, CV_DRIVER, NULL);
538 	cv_init(&vdc->sync_blocked_cv, NULL, CV_DRIVER, NULL);
539 
540 	/* init blocking msg read functionality */
541 	mutex_init(&vdc->read_lock, NULL, MUTEX_DRIVER, NULL);
542 	cv_init(&vdc->read_cv, NULL, CV_DRIVER, NULL);
543 	vdc->read_state = VDC_READ_IDLE;
544 
545 	vdc->initialized |= VDC_LOCKS;
546 
547 	/* initialise LDC channel which will be used to communicate with vds */
548 	if ((status = vdc_do_ldc_init(vdc)) != 0) {
549 		cmn_err(CE_NOTE, "[%d] Couldn't initialize LDC", instance);
550 		goto return_status;
551 	}
552 
553 	/* initialize the thread responsible for managing state with server */
554 	vdc->msg_proc_thr = thread_create(NULL, 0, vdc_process_msg_thread,
555 	    vdc, 0, &p0, TS_RUN, minclsyspri);
556 	if (vdc->msg_proc_thr == NULL) {
557 		cmn_err(CE_NOTE, "[%d] Failed to create msg processing thread",
558 		    instance);
559 		return (DDI_FAILURE);
560 	}
561 
562 	vdc->initialized |= VDC_THREAD;
563 
564 	atomic_inc_32(&vdc_instance_count);
565 
566 	/*
567 	 * Once the handshake is complete, we can use the DRing to send
568 	 * requests to the vDisk server to calculate the geometry and
569 	 * VTOC of the "disk"
570 	 */
571 	status = vdc_setup_disk_layout(vdc);
572 	if (status != 0) {
573 		DMSG(vdc, 0, "[%d] Failed to discover disk layout (err%d)",
574 			vdc->instance, status);
575 		goto return_status;
576 	}
577 
578 	/*
579 	 * Now that we have the device info we can create the
580 	 * device nodes and properties
581 	 */
582 	status = vdc_create_device_nodes(vdc);
583 	if (status) {
584 		DMSG(vdc, 0, "[%d] Failed to create device nodes",
585 				instance);
586 		goto return_status;
587 	}
588 	status = vdc_create_device_nodes_props(vdc);
589 	if (status) {
590 		DMSG(vdc, 0, "[%d] Failed to create device nodes"
591 				" properties (%d)", instance, status);
592 		goto return_status;
593 	}
594 
595 	/*
596 	 * Setup devid
597 	 */
598 	if (vdc_setup_devid(vdc)) {
599 		DMSG(vdc, 0, "[%d] No device id available\n", instance);
600 	}
601 
602 	ddi_report_dev(dip);
603 	vdc->lifecycle	= VDC_LC_ONLINE;
604 	DMSG(vdc, 0, "[%d] Attach tasks successful\n", instance);
605 
606 return_status:
607 	DMSG(vdc, 0, "[%d] Attach completed\n", instance);
608 	return (status);
609 }
610 
611 static int
612 vdc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
613 {
614 	int	status;
615 
616 	switch (cmd) {
617 	case DDI_ATTACH:
618 		if ((status = vdc_do_attach(dip)) != 0)
619 			(void) vdc_detach(dip, DDI_DETACH);
620 		return (status);
621 	case DDI_RESUME:
622 		/* nothing to do for this non-device */
623 		return (DDI_SUCCESS);
624 	default:
625 		return (DDI_FAILURE);
626 	}
627 }
628 
629 static int
630 vdc_do_ldc_init(vdc_t *vdc)
631 {
632 	int			status = 0;
633 	ldc_status_t		ldc_state;
634 	ldc_attr_t		ldc_attr;
635 	uint64_t		ldc_id = 0;
636 	dev_info_t		*dip = NULL;
637 
638 	ASSERT(vdc != NULL);
639 
640 	dip = vdc->dip;
641 	vdc->initialized |= VDC_LDC;
642 
643 	if ((status = vdc_get_ldc_id(dip, &ldc_id)) != 0) {
644 		DMSG(vdc, 0, "[%d] Failed to get LDC channel ID property",
645 				vdc->instance);
646 		return (EIO);
647 	}
648 	vdc->ldc_id = ldc_id;
649 
650 	ldc_attr.devclass = LDC_DEV_BLK;
651 	ldc_attr.instance = vdc->instance;
652 	ldc_attr.mode = LDC_MODE_UNRELIABLE;	/* unreliable transport */
653 	ldc_attr.mtu = VD_LDC_MTU;
654 
655 	if ((vdc->initialized & VDC_LDC_INIT) == 0) {
656 		status = ldc_init(ldc_id, &ldc_attr, &vdc->ldc_handle);
657 		if (status != 0) {
658 			DMSG(vdc, 0, "[%d] ldc_init(chan %ld) returned %d",
659 					vdc->instance, ldc_id, status);
660 			return (status);
661 		}
662 		vdc->initialized |= VDC_LDC_INIT;
663 	}
664 	status = ldc_status(vdc->ldc_handle, &ldc_state);
665 	if (status != 0) {
666 		DMSG(vdc, 0, "[%d] Cannot discover LDC status [err=%d]",
667 				vdc->instance, status);
668 		return (status);
669 	}
670 	vdc->ldc_state = ldc_state;
671 
672 	if ((vdc->initialized & VDC_LDC_CB) == 0) {
673 		status = ldc_reg_callback(vdc->ldc_handle, vdc_handle_cb,
674 		    (caddr_t)vdc);
675 		if (status != 0) {
676 			DMSG(vdc, 0, "[%d] LDC callback reg. failed (%d)",
677 					vdc->instance, status);
678 			return (status);
679 		}
680 		vdc->initialized |= VDC_LDC_CB;
681 	}
682 
683 	vdc->initialized |= VDC_LDC;
684 
685 	/*
686 	 * At this stage we have initialised LDC, we will now try and open
687 	 * the connection.
688 	 */
689 	if (vdc->ldc_state == LDC_INIT) {
690 		status = ldc_open(vdc->ldc_handle);
691 		if (status != 0) {
692 			DMSG(vdc, 0, "[%d] ldc_open(chan %ld) returned %d",
693 					vdc->instance, vdc->ldc_id, status);
694 			return (status);
695 		}
696 		vdc->initialized |= VDC_LDC_OPEN;
697 	}
698 
699 	return (status);
700 }
701 
702 static int
703 vdc_start_ldc_connection(vdc_t *vdc)
704 {
705 	int		status = 0;
706 
707 	ASSERT(vdc != NULL);
708 
709 	ASSERT(MUTEX_HELD(&vdc->lock));
710 
711 	status = vdc_do_ldc_up(vdc);
712 
713 	DMSG(vdc, 0, "[%d] Finished bringing up LDC\n", vdc->instance);
714 
715 	return (status);
716 }
717 
718 static int
719 vdc_stop_ldc_connection(vdc_t *vdcp)
720 {
721 	int	status;
722 
723 	DMSG(vdcp, 0, ": Resetting connection to vDisk server : state %d\n",
724 		vdcp->state);
725 
726 	status = ldc_down(vdcp->ldc_handle);
727 	DMSG(vdcp, 0, "ldc_down() = %d\n", status);
728 
729 	vdcp->initialized &= ~VDC_HANDSHAKE;
730 	DMSG(vdcp, 0, "initialized=%x\n", vdcp->initialized);
731 
732 	return (status);
733 }
734 
735 static int
736 vdc_create_device_nodes_efi(vdc_t *vdc)
737 {
738 	ddi_remove_minor_node(vdc->dip, "h");
739 	ddi_remove_minor_node(vdc->dip, "h,raw");
740 
741 	if (ddi_create_minor_node(vdc->dip, "wd", S_IFBLK,
742 		VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
743 		DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
744 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'wd'",
745 		    vdc->instance);
746 		return (EIO);
747 	}
748 
749 	/* if any device node is created we set this flag */
750 	vdc->initialized |= VDC_MINOR;
751 
752 	if (ddi_create_minor_node(vdc->dip, "wd,raw", S_IFCHR,
753 		VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
754 		DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
755 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'wd,raw'",
756 		    vdc->instance);
757 		return (EIO);
758 	}
759 
760 	return (0);
761 }
762 
763 static int
764 vdc_create_device_nodes_vtoc(vdc_t *vdc)
765 {
766 	ddi_remove_minor_node(vdc->dip, "wd");
767 	ddi_remove_minor_node(vdc->dip, "wd,raw");
768 
769 	if (ddi_create_minor_node(vdc->dip, "h", S_IFBLK,
770 		VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
771 		DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
772 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'h'",
773 		    vdc->instance);
774 		return (EIO);
775 	}
776 
777 	/* if any device node is created we set this flag */
778 	vdc->initialized |= VDC_MINOR;
779 
780 	if (ddi_create_minor_node(vdc->dip, "h,raw", S_IFCHR,
781 		VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
782 		DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
783 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'h,raw'",
784 		    vdc->instance);
785 		return (EIO);
786 	}
787 
788 	return (0);
789 }
790 
791 /*
792  * Function:
793  *	vdc_create_device_nodes
794  *
795  * Description:
796  *	This function creates the block and character device nodes under
797  *	/devices along with the node properties. It is called as part of
798  *	the attach(9E) of the instance during the handshake with vds after
799  *	vds has sent the attributes to vdc.
800  *
801  *	If the device is of type VD_DISK_TYPE_SLICE then the minor node
802  *	of 2 is used in keeping with the Solaris convention that slice 2
803  *	refers to a whole disk. Slices start at 'a'
804  *
805  * Parameters:
806  *	vdc 		- soft state pointer
807  *
808  * Return Values
809  *	0		- Success
810  *	EIO		- Failed to create node
811  *	EINVAL		- Unknown type of disk exported
812  */
813 static int
814 vdc_create_device_nodes(vdc_t *vdc)
815 {
816 	char		name[sizeof ("s,raw")];
817 	dev_info_t	*dip = NULL;
818 	int		instance, status;
819 	int		num_slices = 1;
820 	int		i;
821 
822 	ASSERT(vdc != NULL);
823 
824 	instance = vdc->instance;
825 	dip = vdc->dip;
826 
827 	switch (vdc->vdisk_type) {
828 	case VD_DISK_TYPE_DISK:
829 		num_slices = V_NUMPAR;
830 		break;
831 	case VD_DISK_TYPE_SLICE:
832 		num_slices = 1;
833 		break;
834 	case VD_DISK_TYPE_UNK:
835 	default:
836 		return (EINVAL);
837 	}
838 
839 	/*
840 	 * Minor nodes are different for EFI disks: EFI disks do not have
841 	 * a minor node 'g' for the minor number corresponding to slice
842 	 * VD_EFI_WD_SLICE (slice 7) instead they have a minor node 'wd'
843 	 * representing the whole disk.
844 	 */
845 	for (i = 0; i < num_slices; i++) {
846 
847 		if (i == VD_EFI_WD_SLICE) {
848 			if (vdc->vdisk_label == VD_DISK_LABEL_EFI)
849 				status = vdc_create_device_nodes_efi(vdc);
850 			else
851 				status = vdc_create_device_nodes_vtoc(vdc);
852 			if (status != 0)
853 				return (status);
854 			continue;
855 		}
856 
857 		(void) snprintf(name, sizeof (name), "%c", 'a' + i);
858 		if (ddi_create_minor_node(dip, name, S_IFBLK,
859 		    VD_MAKE_DEV(instance, i), DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
860 			cmn_err(CE_NOTE, "[%d] Couldn't add block node '%s'",
861 				instance, name);
862 			return (EIO);
863 		}
864 
865 		/* if any device node is created we set this flag */
866 		vdc->initialized |= VDC_MINOR;
867 
868 		(void) snprintf(name, sizeof (name), "%c%s",
869 			'a' + i, ",raw");
870 		if (ddi_create_minor_node(dip, name, S_IFCHR,
871 		    VD_MAKE_DEV(instance, i), DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
872 			cmn_err(CE_NOTE, "[%d] Couldn't add raw node '%s'",
873 				instance, name);
874 			return (EIO);
875 		}
876 	}
877 
878 	return (0);
879 }
880 
881 /*
882  * Function:
883  *	vdc_create_device_nodes_props
884  *
885  * Description:
886  *	This function creates the block and character device nodes under
887  *	/devices along with the node properties. It is called as part of
888  *	the attach(9E) of the instance during the handshake with vds after
889  *	vds has sent the attributes to vdc.
890  *
891  * Parameters:
892  *	vdc 		- soft state pointer
893  *
894  * Return Values
895  *	0		- Success
896  *	EIO		- Failed to create device node property
897  *	EINVAL		- Unknown type of disk exported
898  */
899 static int
900 vdc_create_device_nodes_props(vdc_t *vdc)
901 {
902 	dev_info_t	*dip = NULL;
903 	int		instance;
904 	int		num_slices = 1;
905 	int64_t		size = 0;
906 	dev_t		dev;
907 	int		rv;
908 	int		i;
909 
910 	ASSERT(vdc != NULL);
911 
912 	instance = vdc->instance;
913 	dip = vdc->dip;
914 
915 	if ((vdc->vtoc == NULL) || (vdc->vtoc->v_sanity != VTOC_SANE)) {
916 		DMSG(vdc, 0, "![%d] Could not create device node property."
917 				" No VTOC available", instance);
918 		return (ENXIO);
919 	}
920 
921 	switch (vdc->vdisk_type) {
922 	case VD_DISK_TYPE_DISK:
923 		num_slices = V_NUMPAR;
924 		break;
925 	case VD_DISK_TYPE_SLICE:
926 		num_slices = 1;
927 		break;
928 	case VD_DISK_TYPE_UNK:
929 	default:
930 		return (EINVAL);
931 	}
932 
933 	for (i = 0; i < num_slices; i++) {
934 		dev = makedevice(ddi_driver_major(dip),
935 			VD_MAKE_DEV(instance, i));
936 
937 		size = vdc->vtoc->v_part[i].p_size * vdc->vtoc->v_sectorsz;
938 		DMSG(vdc, 0, "[%d] sz %ld (%ld Mb)  p_size %lx\n",
939 				instance, size, size / (1024 * 1024),
940 				vdc->vtoc->v_part[i].p_size);
941 
942 		rv = ddi_prop_update_int64(dev, dip, VDC_SIZE_PROP_NAME, size);
943 		if (rv != DDI_PROP_SUCCESS) {
944 			cmn_err(CE_NOTE, "[%d] Couldn't add '%s' prop of [%ld]",
945 				instance, VDC_SIZE_PROP_NAME, size);
946 			return (EIO);
947 		}
948 
949 		rv = ddi_prop_update_int64(dev, dip, VDC_NBLOCKS_PROP_NAME,
950 			lbtodb(size));
951 		if (rv != DDI_PROP_SUCCESS) {
952 			cmn_err(CE_NOTE, "[%d] Couldn't add '%s' prop [%llu]",
953 				instance, VDC_NBLOCKS_PROP_NAME, lbtodb(size));
954 			return (EIO);
955 		}
956 	}
957 
958 	return (0);
959 }
960 
961 static int
962 vdc_open(dev_t *dev, int flag, int otyp, cred_t *cred)
963 {
964 	_NOTE(ARGUNUSED(cred))
965 
966 	int		instance;
967 	vdc_t		*vdc;
968 
969 	ASSERT(dev != NULL);
970 	instance = VDCUNIT(*dev);
971 
972 	if ((otyp != OTYP_CHR) && (otyp != OTYP_BLK))
973 		return (EINVAL);
974 
975 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
976 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
977 		return (ENXIO);
978 	}
979 
980 	DMSG(vdc, 0, "minor = %d flag = %x, otyp = %x\n",
981 			getminor(*dev), flag, otyp);
982 
983 	mutex_enter(&vdc->lock);
984 	vdc->open_count++;
985 	mutex_exit(&vdc->lock);
986 
987 	return (0);
988 }
989 
990 static int
991 vdc_close(dev_t dev, int flag, int otyp, cred_t *cred)
992 {
993 	_NOTE(ARGUNUSED(cred))
994 
995 	int	instance;
996 	vdc_t	*vdc;
997 
998 	instance = VDCUNIT(dev);
999 
1000 	if ((otyp != OTYP_CHR) && (otyp != OTYP_BLK))
1001 		return (EINVAL);
1002 
1003 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1004 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1005 		return (ENXIO);
1006 	}
1007 
1008 	DMSG(vdc, 0, "[%d] flag = %x, otyp = %x\n", instance, flag, otyp);
1009 	if (vdc->dkio_flush_pending) {
1010 		DMSG(vdc, 0,
1011 		    "[%d] Cannot detach: %d outstanding DKIO flushes\n",
1012 		    instance, vdc->dkio_flush_pending);
1013 		return (EBUSY);
1014 	}
1015 
1016 	/*
1017 	 * Should not need the mutex here, since the framework should protect
1018 	 * against more opens on this device, but just in case.
1019 	 */
1020 	mutex_enter(&vdc->lock);
1021 	vdc->open_count--;
1022 	mutex_exit(&vdc->lock);
1023 
1024 	return (0);
1025 }
1026 
1027 static int
1028 vdc_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *credp, int *rvalp)
1029 {
1030 	_NOTE(ARGUNUSED(credp))
1031 	_NOTE(ARGUNUSED(rvalp))
1032 
1033 	return (vd_process_ioctl(dev, cmd, (caddr_t)arg, mode));
1034 }
1035 
1036 static int
1037 vdc_print(dev_t dev, char *str)
1038 {
1039 	cmn_err(CE_NOTE, "vdc%d:  %s", VDCUNIT(dev), str);
1040 	return (0);
1041 }
1042 
1043 static int
1044 vdc_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk)
1045 {
1046 	int	rv;
1047 	size_t	nbytes = nblk * DEV_BSIZE;
1048 	int	instance = VDCUNIT(dev);
1049 	vdc_t	*vdc = NULL;
1050 
1051 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1052 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1053 		return (ENXIO);
1054 	}
1055 
1056 	DMSG(vdc, 2, "[%d] dump %ld bytes at block 0x%lx : addr=0x%p\n",
1057 	    instance, nbytes, blkno, (void *)addr);
1058 	rv = vdc_send_request(vdc, VD_OP_BWRITE, addr, nbytes,
1059 	    VDCPART(dev), blkno, CB_STRATEGY, 0, VIO_write_dir);
1060 	if (rv) {
1061 		DMSG(vdc, 0, "Failed to do a disk dump (err=%d)\n", rv);
1062 		return (rv);
1063 	}
1064 
1065 	if (ddi_in_panic())
1066 		(void) vdc_drain_response(vdc);
1067 
1068 	DMSG(vdc, 0, "[%d] End\n", instance);
1069 
1070 	return (0);
1071 }
1072 
1073 /* -------------------------------------------------------------------------- */
1074 
1075 /*
1076  * Disk access routines
1077  *
1078  */
1079 
1080 /*
1081  * vdc_strategy()
1082  *
1083  * Return Value:
1084  *	0:	As per strategy(9E), the strategy() function must return 0
1085  *		[ bioerror(9f) sets b_flags to the proper error code ]
1086  */
1087 static int
1088 vdc_strategy(struct buf *buf)
1089 {
1090 	int	rv = -1;
1091 	vdc_t	*vdc = NULL;
1092 	int	instance = VDCUNIT(buf->b_edev);
1093 	int	op = (buf->b_flags & B_READ) ? VD_OP_BREAD : VD_OP_BWRITE;
1094 
1095 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1096 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1097 		bioerror(buf, ENXIO);
1098 		biodone(buf);
1099 		return (0);
1100 	}
1101 
1102 	DMSG(vdc, 2, "[%d] %s %ld bytes at block %llx : b_addr=0x%p\n",
1103 	    instance, (buf->b_flags & B_READ) ? "Read" : "Write",
1104 	    buf->b_bcount, buf->b_lblkno, (void *)buf->b_un.b_addr);
1105 	DTRACE_IO2(vstart, buf_t *, buf, vdc_t *, vdc);
1106 
1107 	bp_mapin(buf);
1108 
1109 	rv = vdc_send_request(vdc, op, (caddr_t)buf->b_un.b_addr,
1110 	    buf->b_bcount, VDCPART(buf->b_edev), buf->b_lblkno,
1111 	    CB_STRATEGY, buf, (op == VD_OP_BREAD) ? VIO_read_dir :
1112 	    VIO_write_dir);
1113 
1114 	/*
1115 	 * If the request was successfully sent, the strategy call returns and
1116 	 * the ACK handler calls the bioxxx functions when the vDisk server is
1117 	 * done.
1118 	 */
1119 	if (rv) {
1120 		DMSG(vdc, 0, "Failed to read/write (err=%d)\n", rv);
1121 		bioerror(buf, rv);
1122 		biodone(buf);
1123 	}
1124 
1125 	return (0);
1126 }
1127 
1128 /*
1129  * Function:
1130  *	vdc_min
1131  *
1132  * Description:
1133  *	Routine to limit the size of a data transfer. Used in
1134  *	conjunction with physio(9F).
1135  *
1136  * Arguments:
1137  *	bp - pointer to the indicated buf(9S) struct.
1138  *
1139  */
1140 static void
1141 vdc_min(struct buf *bufp)
1142 {
1143 	vdc_t	*vdc = NULL;
1144 	int	instance = VDCUNIT(bufp->b_edev);
1145 
1146 	vdc = ddi_get_soft_state(vdc_state, instance);
1147 	VERIFY(vdc != NULL);
1148 
1149 	if (bufp->b_bcount > (vdc->max_xfer_sz * vdc->block_size)) {
1150 		bufp->b_bcount = vdc->max_xfer_sz * vdc->block_size;
1151 	}
1152 }
1153 
1154 static int
1155 vdc_read(dev_t dev, struct uio *uio, cred_t *cred)
1156 {
1157 	_NOTE(ARGUNUSED(cred))
1158 
1159 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1160 	return (physio(vdc_strategy, NULL, dev, B_READ, vdc_min, uio));
1161 }
1162 
1163 static int
1164 vdc_write(dev_t dev, struct uio *uio, cred_t *cred)
1165 {
1166 	_NOTE(ARGUNUSED(cred))
1167 
1168 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1169 	return (physio(vdc_strategy, NULL, dev, B_WRITE, vdc_min, uio));
1170 }
1171 
1172 static int
1173 vdc_aread(dev_t dev, struct aio_req *aio, cred_t *cred)
1174 {
1175 	_NOTE(ARGUNUSED(cred))
1176 
1177 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1178 	return (aphysio(vdc_strategy, anocancel, dev, B_READ, vdc_min, aio));
1179 }
1180 
1181 static int
1182 vdc_awrite(dev_t dev, struct aio_req *aio, cred_t *cred)
1183 {
1184 	_NOTE(ARGUNUSED(cred))
1185 
1186 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1187 	return (aphysio(vdc_strategy, anocancel, dev, B_WRITE, vdc_min, aio));
1188 }
1189 
1190 
1191 /* -------------------------------------------------------------------------- */
1192 
1193 /*
1194  * Handshake support
1195  */
1196 
1197 
1198 /*
1199  * Function:
1200  *	vdc_init_ver_negotiation()
1201  *
1202  * Description:
1203  *
1204  * Arguments:
1205  *	vdc	- soft state pointer for this instance of the device driver.
1206  *
1207  * Return Code:
1208  *	0	- Success
1209  */
1210 static int
1211 vdc_init_ver_negotiation(vdc_t *vdc, vio_ver_t ver)
1212 {
1213 	vio_ver_msg_t	pkt;
1214 	size_t		msglen = sizeof (pkt);
1215 	int		status = -1;
1216 
1217 	ASSERT(vdc != NULL);
1218 	ASSERT(mutex_owned(&vdc->lock));
1219 
1220 	DMSG(vdc, 0, "[%d] Entered.\n", vdc->instance);
1221 
1222 	/*
1223 	 * set the Session ID to a unique value
1224 	 * (the lower 32 bits of the clock tick)
1225 	 */
1226 	vdc->session_id = ((uint32_t)gettick() & 0xffffffff);
1227 	DMSG(vdc, 0, "[%d] Set SID to 0x%lx\n", vdc->instance, vdc->session_id);
1228 
1229 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1230 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1231 	pkt.tag.vio_subtype_env = VIO_VER_INFO;
1232 	pkt.tag.vio_sid = vdc->session_id;
1233 	pkt.dev_class = VDEV_DISK;
1234 	pkt.ver_major = ver.major;
1235 	pkt.ver_minor = ver.minor;
1236 
1237 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1238 	DMSG(vdc, 0, "[%d] Ver info sent (status = %d)\n",
1239 	    vdc->instance, status);
1240 	if ((status != 0) || (msglen != sizeof (vio_ver_msg_t))) {
1241 		DMSG(vdc, 0, "[%d] Failed to send Ver negotiation info: "
1242 				"id(%lx) rv(%d) size(%ld)",
1243 				vdc->instance, vdc->ldc_handle,
1244 				status, msglen);
1245 		if (msglen != sizeof (vio_ver_msg_t))
1246 			status = ENOMSG;
1247 	}
1248 
1249 	return (status);
1250 }
1251 
1252 /*
1253  * Function:
1254  *	vdc_ver_negotiation()
1255  *
1256  * Description:
1257  *
1258  * Arguments:
1259  *	vdcp	- soft state pointer for this instance of the device driver.
1260  *
1261  * Return Code:
1262  *	0	- Success
1263  */
1264 static int
1265 vdc_ver_negotiation(vdc_t *vdcp)
1266 {
1267 	vio_msg_t vio_msg;
1268 	int status;
1269 
1270 	if (status = vdc_init_ver_negotiation(vdcp, vdc_version[0]))
1271 		return (status);
1272 
1273 	/* release lock and wait for response */
1274 	mutex_exit(&vdcp->lock);
1275 	status = vdc_wait_for_response(vdcp, &vio_msg);
1276 	mutex_enter(&vdcp->lock);
1277 	if (status) {
1278 		DMSG(vdcp, 0,
1279 		    "[%d] Failed waiting for Ver negotiation response, rv(%d)",
1280 		    vdcp->instance, status);
1281 		return (status);
1282 	}
1283 
1284 	/* check type and sub_type ... */
1285 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1286 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1287 		DMSG(vdcp, 0, "[%d] Invalid ver negotiation response\n",
1288 				vdcp->instance);
1289 		return (EPROTO);
1290 	}
1291 
1292 	return (vdc_handle_ver_msg(vdcp, (vio_ver_msg_t *)&vio_msg));
1293 }
1294 
1295 /*
1296  * Function:
1297  *	vdc_init_attr_negotiation()
1298  *
1299  * Description:
1300  *
1301  * Arguments:
1302  *	vdc	- soft state pointer for this instance of the device driver.
1303  *
1304  * Return Code:
1305  *	0	- Success
1306  */
1307 static int
1308 vdc_init_attr_negotiation(vdc_t *vdc)
1309 {
1310 	vd_attr_msg_t	pkt;
1311 	size_t		msglen = sizeof (pkt);
1312 	int		status;
1313 
1314 	ASSERT(vdc != NULL);
1315 	ASSERT(mutex_owned(&vdc->lock));
1316 
1317 	DMSG(vdc, 0, "[%d] entered\n", vdc->instance);
1318 
1319 	/* fill in tag */
1320 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1321 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1322 	pkt.tag.vio_subtype_env = VIO_ATTR_INFO;
1323 	pkt.tag.vio_sid = vdc->session_id;
1324 	/* fill in payload */
1325 	pkt.max_xfer_sz = vdc->max_xfer_sz;
1326 	pkt.vdisk_block_size = vdc->block_size;
1327 	pkt.xfer_mode = VIO_DRING_MODE;
1328 	pkt.operations = 0;	/* server will set bits of valid operations */
1329 	pkt.vdisk_type = 0;	/* server will set to valid device type */
1330 	pkt.vdisk_size = 0;	/* server will set to valid size */
1331 
1332 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1333 	DMSG(vdc, 0, "Attr info sent (status = %d)\n", status);
1334 
1335 	if ((status != 0) || (msglen != sizeof (vio_ver_msg_t))) {
1336 		DMSG(vdc, 0, "[%d] Failed to send Attr negotiation info: "
1337 				"id(%lx) rv(%d) size(%ld)",
1338 				vdc->instance, vdc->ldc_handle,
1339 				status, msglen);
1340 		if (msglen != sizeof (vio_ver_msg_t))
1341 			status = ENOMSG;
1342 	}
1343 
1344 	return (status);
1345 }
1346 
1347 /*
1348  * Function:
1349  *	vdc_attr_negotiation()
1350  *
1351  * Description:
1352  *
1353  * Arguments:
1354  *	vdc	- soft state pointer for this instance of the device driver.
1355  *
1356  * Return Code:
1357  *	0	- Success
1358  */
1359 static int
1360 vdc_attr_negotiation(vdc_t *vdcp)
1361 {
1362 	int status;
1363 	vio_msg_t vio_msg;
1364 
1365 	if (status = vdc_init_attr_negotiation(vdcp))
1366 		return (status);
1367 
1368 	/* release lock and wait for response */
1369 	mutex_exit(&vdcp->lock);
1370 	status = vdc_wait_for_response(vdcp, &vio_msg);
1371 	mutex_enter(&vdcp->lock);
1372 	if (status) {
1373 		DMSG(vdcp, 0,
1374 		    "[%d] Failed waiting for Attr negotiation response, rv(%d)",
1375 		    vdcp->instance, status);
1376 		return (status);
1377 	}
1378 
1379 	/* check type and sub_type ... */
1380 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1381 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1382 		DMSG(vdcp, 0, "[%d] Invalid attr negotiation response\n",
1383 				vdcp->instance);
1384 		return (EPROTO);
1385 	}
1386 
1387 	return (vdc_handle_attr_msg(vdcp, (vd_attr_msg_t *)&vio_msg));
1388 }
1389 
1390 
1391 /*
1392  * Function:
1393  *	vdc_init_dring_negotiate()
1394  *
1395  * Description:
1396  *
1397  * Arguments:
1398  *	vdc	- soft state pointer for this instance of the device driver.
1399  *
1400  * Return Code:
1401  *	0	- Success
1402  */
1403 static int
1404 vdc_init_dring_negotiate(vdc_t *vdc)
1405 {
1406 	vio_dring_reg_msg_t	pkt;
1407 	size_t			msglen = sizeof (pkt);
1408 	int			status = -1;
1409 	int			retry;
1410 	int			nretries = 10;
1411 
1412 	ASSERT(vdc != NULL);
1413 	ASSERT(mutex_owned(&vdc->lock));
1414 
1415 	for (retry = 0; retry < nretries; retry++) {
1416 		status = vdc_init_descriptor_ring(vdc);
1417 		if (status != EAGAIN)
1418 			break;
1419 		drv_usecwait(vdc_min_timeout_ldc);
1420 	}
1421 
1422 	if (status != 0) {
1423 		DMSG(vdc, 0, "[%d] Failed to init DRing (status = %d)\n",
1424 				vdc->instance, status);
1425 		return (status);
1426 	}
1427 
1428 	DMSG(vdc, 0, "[%d] Init of descriptor ring completed (status = %d)\n",
1429 			vdc->instance, status);
1430 
1431 	/* fill in tag */
1432 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1433 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1434 	pkt.tag.vio_subtype_env = VIO_DRING_REG;
1435 	pkt.tag.vio_sid = vdc->session_id;
1436 	/* fill in payload */
1437 	pkt.dring_ident = 0;
1438 	pkt.num_descriptors = vdc->dring_len;
1439 	pkt.descriptor_size = vdc->dring_entry_size;
1440 	pkt.options = (VIO_TX_DRING | VIO_RX_DRING);
1441 	pkt.ncookies = vdc->dring_cookie_count;
1442 	pkt.cookie[0] = vdc->dring_cookie[0];	/* for now just one cookie */
1443 
1444 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1445 	if (status != 0) {
1446 		DMSG(vdc, 0, "[%d] Failed to register DRing (err = %d)",
1447 				vdc->instance, status);
1448 	}
1449 
1450 	return (status);
1451 }
1452 
1453 
1454 /*
1455  * Function:
1456  *	vdc_dring_negotiation()
1457  *
1458  * Description:
1459  *
1460  * Arguments:
1461  *	vdc	- soft state pointer for this instance of the device driver.
1462  *
1463  * Return Code:
1464  *	0	- Success
1465  */
1466 static int
1467 vdc_dring_negotiation(vdc_t *vdcp)
1468 {
1469 	int status;
1470 	vio_msg_t vio_msg;
1471 
1472 	if (status = vdc_init_dring_negotiate(vdcp))
1473 		return (status);
1474 
1475 	/* release lock and wait for response */
1476 	mutex_exit(&vdcp->lock);
1477 	status = vdc_wait_for_response(vdcp, &vio_msg);
1478 	mutex_enter(&vdcp->lock);
1479 	if (status) {
1480 		DMSG(vdcp, 0,
1481 		    "[%d] Failed waiting for Dring negotiation response,"
1482 		    " rv(%d)", vdcp->instance, status);
1483 		return (status);
1484 	}
1485 
1486 	/* check type and sub_type ... */
1487 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1488 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1489 		DMSG(vdcp, 0, "[%d] Invalid Dring negotiation response\n",
1490 				vdcp->instance);
1491 		return (EPROTO);
1492 	}
1493 
1494 	return (vdc_handle_dring_reg_msg(vdcp,
1495 		    (vio_dring_reg_msg_t *)&vio_msg));
1496 }
1497 
1498 
1499 /*
1500  * Function:
1501  *	vdc_send_rdx()
1502  *
1503  * Description:
1504  *
1505  * Arguments:
1506  *	vdc	- soft state pointer for this instance of the device driver.
1507  *
1508  * Return Code:
1509  *	0	- Success
1510  */
1511 static int
1512 vdc_send_rdx(vdc_t *vdcp)
1513 {
1514 	vio_msg_t	msg;
1515 	size_t		msglen = sizeof (vio_msg_t);
1516 	int		status;
1517 
1518 	/*
1519 	 * Send an RDX message to vds to indicate we are ready
1520 	 * to send data
1521 	 */
1522 	msg.tag.vio_msgtype = VIO_TYPE_CTRL;
1523 	msg.tag.vio_subtype = VIO_SUBTYPE_INFO;
1524 	msg.tag.vio_subtype_env = VIO_RDX;
1525 	msg.tag.vio_sid = vdcp->session_id;
1526 	status = vdc_send(vdcp, (caddr_t)&msg, &msglen);
1527 	if (status != 0) {
1528 		DMSG(vdcp, 0, "[%d] Failed to send RDX message (%d)",
1529 		    vdcp->instance, status);
1530 	}
1531 
1532 	return (status);
1533 }
1534 
1535 /*
1536  * Function:
1537  *	vdc_handle_rdx()
1538  *
1539  * Description:
1540  *
1541  * Arguments:
1542  *	vdc	- soft state pointer for this instance of the device driver.
1543  *	msgp	- received msg
1544  *
1545  * Return Code:
1546  *	0	- Success
1547  */
1548 static int
1549 vdc_handle_rdx(vdc_t *vdcp, vio_rdx_msg_t *msgp)
1550 {
1551 	_NOTE(ARGUNUSED(vdcp))
1552 	_NOTE(ARGUNUSED(msgp))
1553 
1554 	ASSERT(msgp->tag.vio_msgtype == VIO_TYPE_CTRL);
1555 	ASSERT(msgp->tag.vio_subtype == VIO_SUBTYPE_ACK);
1556 	ASSERT(msgp->tag.vio_subtype_env == VIO_RDX);
1557 
1558 	DMSG(vdcp, 1, "[%d] Got an RDX msg", vdcp->instance);
1559 
1560 	return (0);
1561 }
1562 
1563 /*
1564  * Function:
1565  *	vdc_rdx_exchange()
1566  *
1567  * Description:
1568  *
1569  * Arguments:
1570  *	vdc	- soft state pointer for this instance of the device driver.
1571  *
1572  * Return Code:
1573  *	0	- Success
1574  */
1575 static int
1576 vdc_rdx_exchange(vdc_t *vdcp)
1577 {
1578 	int status;
1579 	vio_msg_t vio_msg;
1580 
1581 	if (status = vdc_send_rdx(vdcp))
1582 		return (status);
1583 
1584 	/* release lock and wait for response */
1585 	mutex_exit(&vdcp->lock);
1586 	status = vdc_wait_for_response(vdcp, &vio_msg);
1587 	mutex_enter(&vdcp->lock);
1588 	if (status) {
1589 		DMSG(vdcp, 0,
1590 		    "[%d] Failed waiting for RDX response,"
1591 		    " rv(%d)", vdcp->instance, status);
1592 		return (status);
1593 	}
1594 
1595 	/* check type and sub_type ... */
1596 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1597 	    vio_msg.tag.vio_subtype != VIO_SUBTYPE_ACK) {
1598 		DMSG(vdcp, 0, "[%d] Invalid RDX response\n",
1599 				vdcp->instance);
1600 		return (EPROTO);
1601 	}
1602 
1603 	return (vdc_handle_rdx(vdcp, (vio_rdx_msg_t *)&vio_msg));
1604 }
1605 
1606 
1607 /* -------------------------------------------------------------------------- */
1608 
1609 /*
1610  * LDC helper routines
1611  */
1612 
1613 static int
1614 vdc_recv(vdc_t *vdc, vio_msg_t *msgp, size_t *nbytesp)
1615 {
1616 	int		status;
1617 	boolean_t	q_has_pkts = B_FALSE;
1618 	int		delay_time;
1619 	size_t		len;
1620 
1621 	mutex_enter(&vdc->read_lock);
1622 
1623 	if (vdc->read_state == VDC_READ_IDLE)
1624 		vdc->read_state = VDC_READ_WAITING;
1625 
1626 	while (vdc->read_state != VDC_READ_PENDING) {
1627 
1628 		/* detect if the connection has been reset */
1629 		if (vdc->read_state == VDC_READ_RESET) {
1630 			status = ECONNRESET;
1631 			goto done;
1632 		}
1633 
1634 		cv_wait(&vdc->read_cv, &vdc->read_lock);
1635 	}
1636 
1637 	/*
1638 	 * Until we get a blocking ldc read we have to retry
1639 	 * until the entire LDC message has arrived before
1640 	 * ldc_read() will succeed. Note we also bail out if
1641 	 * the channel is reset or goes away.
1642 	 */
1643 	delay_time = vdc_ldc_read_init_delay;
1644 loop:
1645 	len = *nbytesp;
1646 	status = ldc_read(vdc->ldc_handle, (caddr_t)msgp, &len);
1647 	switch (status) {
1648 	case EAGAIN:
1649 		delay_time *= 2;
1650 		if (delay_time >= vdc_ldc_read_max_delay)
1651 			delay_time = vdc_ldc_read_max_delay;
1652 		delay(delay_time);
1653 		goto loop;
1654 
1655 	case 0:
1656 		if (len == 0) {
1657 			DMSG(vdc, 0, "[%d] ldc_read returned 0 bytes with "
1658 				"no error!\n", vdc->instance);
1659 			goto loop;
1660 		}
1661 
1662 		*nbytesp = len;
1663 
1664 		/*
1665 		 * If there are pending messages, leave the
1666 		 * read state as pending. Otherwise, set the state
1667 		 * back to idle.
1668 		 */
1669 		status = ldc_chkq(vdc->ldc_handle, &q_has_pkts);
1670 		if (status == 0 && !q_has_pkts)
1671 			vdc->read_state = VDC_READ_IDLE;
1672 
1673 		break;
1674 	default:
1675 		DMSG(vdc, 0, "ldc_read returned %d\n", status);
1676 		break;
1677 	}
1678 
1679 done:
1680 	mutex_exit(&vdc->read_lock);
1681 
1682 	return (status);
1683 }
1684 
1685 
1686 
1687 #ifdef DEBUG
1688 void
1689 vdc_decode_tag(vdc_t *vdcp, vio_msg_t *msg)
1690 {
1691 	char *ms, *ss, *ses;
1692 	switch (msg->tag.vio_msgtype) {
1693 #define	Q(_s)	case _s : ms = #_s; break;
1694 	Q(VIO_TYPE_CTRL)
1695 	Q(VIO_TYPE_DATA)
1696 	Q(VIO_TYPE_ERR)
1697 #undef Q
1698 	default: ms = "unknown"; break;
1699 	}
1700 
1701 	switch (msg->tag.vio_subtype) {
1702 #define	Q(_s)	case _s : ss = #_s; break;
1703 	Q(VIO_SUBTYPE_INFO)
1704 	Q(VIO_SUBTYPE_ACK)
1705 	Q(VIO_SUBTYPE_NACK)
1706 #undef Q
1707 	default: ss = "unknown"; break;
1708 	}
1709 
1710 	switch (msg->tag.vio_subtype_env) {
1711 #define	Q(_s)	case _s : ses = #_s; break;
1712 	Q(VIO_VER_INFO)
1713 	Q(VIO_ATTR_INFO)
1714 	Q(VIO_DRING_REG)
1715 	Q(VIO_DRING_UNREG)
1716 	Q(VIO_RDX)
1717 	Q(VIO_PKT_DATA)
1718 	Q(VIO_DESC_DATA)
1719 	Q(VIO_DRING_DATA)
1720 #undef Q
1721 	default: ses = "unknown"; break;
1722 	}
1723 
1724 	DMSG(vdcp, 3, "(%x/%x/%x) message : (%s/%s/%s)\n",
1725 	    msg->tag.vio_msgtype, msg->tag.vio_subtype,
1726 	    msg->tag.vio_subtype_env, ms, ss, ses);
1727 }
1728 #endif
1729 
1730 /*
1731  * Function:
1732  *	vdc_send()
1733  *
1734  * Description:
1735  *	The function encapsulates the call to write a message using LDC.
1736  *	If LDC indicates that the call failed due to the queue being full,
1737  *	we retry the ldc_write() [ up to 'vdc_retries' time ], otherwise
1738  *	we return the error returned by LDC.
1739  *
1740  * Arguments:
1741  *	ldc_handle	- LDC handle for the channel this instance of vdc uses
1742  *	pkt		- address of LDC message to be sent
1743  *	msglen		- the size of the message being sent. When the function
1744  *			  returns, this contains the number of bytes written.
1745  *
1746  * Return Code:
1747  *	0		- Success.
1748  *	EINVAL		- pkt or msglen were NULL
1749  *	ECONNRESET	- The connection was not up.
1750  *	EWOULDBLOCK	- LDC queue is full
1751  *	xxx		- other error codes returned by ldc_write
1752  */
1753 static int
1754 vdc_send(vdc_t *vdc, caddr_t pkt, size_t *msglen)
1755 {
1756 	size_t	size = 0;
1757 	int	status = 0;
1758 	clock_t delay_ticks;
1759 
1760 	ASSERT(vdc != NULL);
1761 	ASSERT(mutex_owned(&vdc->lock));
1762 	ASSERT(msglen != NULL);
1763 	ASSERT(*msglen != 0);
1764 
1765 #ifdef DEBUG
1766 	vdc_decode_tag(vdc, (vio_msg_t *)pkt);
1767 #endif
1768 	/*
1769 	 * Wait indefinitely to send if channel
1770 	 * is busy, but bail out if we succeed or
1771 	 * if the channel closes or is reset.
1772 	 */
1773 	delay_ticks = vdc_hz_min_ldc_delay;
1774 	do {
1775 		size = *msglen;
1776 		status = ldc_write(vdc->ldc_handle, pkt, &size);
1777 		if (status == EWOULDBLOCK) {
1778 			delay(delay_ticks);
1779 			/* geometric backoff */
1780 			delay_ticks *= 2;
1781 			if (delay_ticks > vdc_hz_max_ldc_delay)
1782 				delay_ticks = vdc_hz_max_ldc_delay;
1783 		}
1784 	} while (status == EWOULDBLOCK);
1785 
1786 	/* if LDC had serious issues --- reset vdc state */
1787 	if (status == EIO || status == ECONNRESET) {
1788 		/* LDC had serious issues --- reset vdc state */
1789 		mutex_enter(&vdc->read_lock);
1790 		if ((vdc->read_state == VDC_READ_WAITING) ||
1791 		    (vdc->read_state == VDC_READ_RESET))
1792 			cv_signal(&vdc->read_cv);
1793 		vdc->read_state = VDC_READ_RESET;
1794 		mutex_exit(&vdc->read_lock);
1795 
1796 		/* wake up any waiters in the reset thread */
1797 		if (vdc->state == VDC_STATE_INIT_WAITING) {
1798 			DMSG(vdc, 0, "[%d] write reset - "
1799 			    "vdc is resetting ..\n", vdc->instance);
1800 			vdc->state = VDC_STATE_RESETTING;
1801 			cv_signal(&vdc->initwait_cv);
1802 		}
1803 
1804 		return (ECONNRESET);
1805 	}
1806 
1807 	/* return the last size written */
1808 	*msglen = size;
1809 
1810 	return (status);
1811 }
1812 
1813 /*
1814  * Function:
1815  *	vdc_get_ldc_id()
1816  *
1817  * Description:
1818  *	This function gets the 'ldc-id' for this particular instance of vdc.
1819  *	The id returned is the guest domain channel endpoint LDC uses for
1820  *	communication with vds.
1821  *
1822  * Arguments:
1823  *	dip	- dev info pointer for this instance of the device driver.
1824  *	ldc_id	- pointer to variable used to return the 'ldc-id' found.
1825  *
1826  * Return Code:
1827  *	0	- Success.
1828  *	ENOENT	- Expected node or property did not exist.
1829  *	ENXIO	- Unexpected error communicating with MD framework
1830  */
1831 static int
1832 vdc_get_ldc_id(dev_info_t *dip, uint64_t *ldc_id)
1833 {
1834 	int		status = ENOENT;
1835 	char		*node_name = NULL;
1836 	md_t		*mdp = NULL;
1837 	int		num_nodes;
1838 	int		num_vdevs;
1839 	int		num_chans;
1840 	mde_cookie_t	rootnode;
1841 	mde_cookie_t	*listp = NULL;
1842 	mde_cookie_t	*chanp = NULL;
1843 	boolean_t	found_inst = B_FALSE;
1844 	int		listsz;
1845 	int		idx;
1846 	uint64_t	md_inst;
1847 	int		obp_inst;
1848 	int		instance = ddi_get_instance(dip);
1849 
1850 	ASSERT(ldc_id != NULL);
1851 	*ldc_id = 0;
1852 
1853 	/*
1854 	 * Get the OBP instance number for comparison with the MD instance
1855 	 *
1856 	 * The "cfg-handle" property of a vdc node in an MD contains the MD's
1857 	 * notion of "instance", or unique identifier, for that node; OBP
1858 	 * stores the value of the "cfg-handle" MD property as the value of
1859 	 * the "reg" property on the node in the device tree it builds from
1860 	 * the MD and passes to Solaris.  Thus, we look up the devinfo node's
1861 	 * "reg" property value to uniquely identify this device instance.
1862 	 * If the "reg" property cannot be found, the device tree state is
1863 	 * presumably so broken that there is no point in continuing.
1864 	 */
1865 	if (!ddi_prop_exists(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS, OBP_REG)) {
1866 		cmn_err(CE_WARN, "'%s' property does not exist", OBP_REG);
1867 		return (ENOENT);
1868 	}
1869 	obp_inst = ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
1870 			OBP_REG, -1);
1871 	DMSGX(1, "[%d] OBP inst=%d\n", instance, obp_inst);
1872 
1873 	/*
1874 	 * We now walk the MD nodes and if an instance of a vdc node matches
1875 	 * the instance got from OBP we get the ldc-id property.
1876 	 */
1877 	if ((mdp = md_get_handle()) == NULL) {
1878 		cmn_err(CE_WARN, "unable to init machine description");
1879 		return (ENXIO);
1880 	}
1881 
1882 	num_nodes = md_node_count(mdp);
1883 	ASSERT(num_nodes > 0);
1884 
1885 	listsz = num_nodes * sizeof (mde_cookie_t);
1886 
1887 	/* allocate memory for nodes */
1888 	listp = kmem_zalloc(listsz, KM_SLEEP);
1889 	chanp = kmem_zalloc(listsz, KM_SLEEP);
1890 
1891 	rootnode = md_root_node(mdp);
1892 	ASSERT(rootnode != MDE_INVAL_ELEM_COOKIE);
1893 
1894 	/*
1895 	 * Search for all the virtual devices, we will then check to see which
1896 	 * ones are disk nodes.
1897 	 */
1898 	num_vdevs = md_scan_dag(mdp, rootnode,
1899 			md_find_name(mdp, VDC_MD_VDEV_NAME),
1900 			md_find_name(mdp, "fwd"), listp);
1901 
1902 	if (num_vdevs <= 0) {
1903 		cmn_err(CE_NOTE, "No '%s' node found", VDC_MD_VDEV_NAME);
1904 		status = ENOENT;
1905 		goto done;
1906 	}
1907 
1908 	DMSGX(1, "[%d] num_vdevs=%d\n", instance, num_vdevs);
1909 	for (idx = 0; idx < num_vdevs; idx++) {
1910 		status = md_get_prop_str(mdp, listp[idx], "name", &node_name);
1911 		if ((status != 0) || (node_name == NULL)) {
1912 			cmn_err(CE_NOTE, "Unable to get name of node type '%s'"
1913 					": err %d", VDC_MD_VDEV_NAME, status);
1914 			continue;
1915 		}
1916 
1917 		DMSGX(1, "[%d] Found node '%s'\n", instance, node_name);
1918 		if (strcmp(VDC_MD_DISK_NAME, node_name) == 0) {
1919 			status = md_get_prop_val(mdp, listp[idx],
1920 					VDC_MD_CFG_HDL, &md_inst);
1921 			DMSGX(1, "[%d] vdc inst in MD=%lx\n",
1922 			    instance, md_inst);
1923 			if ((status == 0) && (md_inst == obp_inst)) {
1924 				found_inst = B_TRUE;
1925 				break;
1926 			}
1927 		}
1928 	}
1929 
1930 	if (!found_inst) {
1931 		DMSGX(0, "Unable to find correct '%s' node", VDC_MD_DISK_NAME);
1932 		status = ENOENT;
1933 		goto done;
1934 	}
1935 	DMSGX(0, "[%d] MD inst=%lx\n", instance, md_inst);
1936 
1937 	/* get the channels for this node */
1938 	num_chans = md_scan_dag(mdp, listp[idx],
1939 			md_find_name(mdp, VDC_MD_CHAN_NAME),
1940 			md_find_name(mdp, "fwd"), chanp);
1941 
1942 	/* expecting at least one channel */
1943 	if (num_chans <= 0) {
1944 		cmn_err(CE_NOTE, "No '%s' node for '%s' port",
1945 				VDC_MD_CHAN_NAME, VDC_MD_VDEV_NAME);
1946 		status = ENOENT;
1947 		goto done;
1948 
1949 	} else if (num_chans != 1) {
1950 		DMSGX(0, "[%d] Expected 1 '%s' node for '%s' port, found %d\n",
1951 			instance, VDC_MD_CHAN_NAME, VDC_MD_VDEV_NAME,
1952 			num_chans);
1953 	}
1954 
1955 	/*
1956 	 * We use the first channel found (index 0), irrespective of how
1957 	 * many are there in total.
1958 	 */
1959 	if (md_get_prop_val(mdp, chanp[0], VDC_ID_PROP, ldc_id) != 0) {
1960 		cmn_err(CE_NOTE, "Channel '%s' property not found",
1961 				VDC_ID_PROP);
1962 		status = ENOENT;
1963 	}
1964 
1965 	DMSGX(0, "[%d] LDC id is 0x%lx\n", instance, *ldc_id);
1966 
1967 done:
1968 	if (chanp)
1969 		kmem_free(chanp, listsz);
1970 	if (listp)
1971 		kmem_free(listp, listsz);
1972 
1973 	(void) md_fini_handle(mdp);
1974 
1975 	return (status);
1976 }
1977 
1978 static int
1979 vdc_do_ldc_up(vdc_t *vdc)
1980 {
1981 	int		status;
1982 	ldc_status_t	ldc_state;
1983 
1984 	DMSG(vdc, 0, "[%d] Bringing up channel %lx\n",
1985 	    vdc->instance, vdc->ldc_id);
1986 
1987 	if (vdc->lifecycle == VDC_LC_DETACHING)
1988 		return (EINVAL);
1989 
1990 	if ((status = ldc_up(vdc->ldc_handle)) != 0) {
1991 		switch (status) {
1992 		case ECONNREFUSED:	/* listener not ready at other end */
1993 			DMSG(vdc, 0, "[%d] ldc_up(%lx,...) return %d\n",
1994 					vdc->instance, vdc->ldc_id, status);
1995 			status = 0;
1996 			break;
1997 		default:
1998 			DMSG(vdc, 0, "[%d] Failed to bring up LDC: "
1999 			    "channel=%ld, err=%d", vdc->instance, vdc->ldc_id,
2000 			    status);
2001 			break;
2002 		}
2003 	}
2004 
2005 	if (ldc_status(vdc->ldc_handle, &ldc_state) == 0) {
2006 		vdc->ldc_state = ldc_state;
2007 		if (ldc_state == LDC_UP) {
2008 			DMSG(vdc, 0, "[%d] LDC channel already up\n",
2009 			    vdc->instance);
2010 			vdc->seq_num = 1;
2011 			vdc->seq_num_reply = 0;
2012 		}
2013 	}
2014 
2015 	return (status);
2016 }
2017 
2018 /*
2019  * Function:
2020  *	vdc_terminate_ldc()
2021  *
2022  * Description:
2023  *
2024  * Arguments:
2025  *	vdc	- soft state pointer for this instance of the device driver.
2026  *
2027  * Return Code:
2028  *	None
2029  */
2030 static void
2031 vdc_terminate_ldc(vdc_t *vdc)
2032 {
2033 	int	instance = ddi_get_instance(vdc->dip);
2034 
2035 	ASSERT(vdc != NULL);
2036 	ASSERT(mutex_owned(&vdc->lock));
2037 
2038 	DMSG(vdc, 0, "[%d] initialized=%x\n", instance, vdc->initialized);
2039 
2040 	if (vdc->initialized & VDC_LDC_OPEN) {
2041 		DMSG(vdc, 0, "[%d] ldc_close()\n", instance);
2042 		(void) ldc_close(vdc->ldc_handle);
2043 	}
2044 	if (vdc->initialized & VDC_LDC_CB) {
2045 		DMSG(vdc, 0, "[%d] ldc_unreg_callback()\n", instance);
2046 		(void) ldc_unreg_callback(vdc->ldc_handle);
2047 	}
2048 	if (vdc->initialized & VDC_LDC) {
2049 		DMSG(vdc, 0, "[%d] ldc_fini()\n", instance);
2050 		(void) ldc_fini(vdc->ldc_handle);
2051 		vdc->ldc_handle = NULL;
2052 	}
2053 
2054 	vdc->initialized &= ~(VDC_LDC | VDC_LDC_CB | VDC_LDC_OPEN);
2055 }
2056 
2057 /* -------------------------------------------------------------------------- */
2058 
2059 /*
2060  * Descriptor Ring helper routines
2061  */
2062 
2063 /*
2064  * Function:
2065  *	vdc_init_descriptor_ring()
2066  *
2067  * Description:
2068  *
2069  * Arguments:
2070  *	vdc	- soft state pointer for this instance of the device driver.
2071  *
2072  * Return Code:
2073  *	0	- Success
2074  */
2075 static int
2076 vdc_init_descriptor_ring(vdc_t *vdc)
2077 {
2078 	vd_dring_entry_t	*dep = NULL;	/* DRing Entry pointer */
2079 	int	status = 0;
2080 	int	i;
2081 
2082 	DMSG(vdc, 0, "[%d] initialized=%x\n", vdc->instance, vdc->initialized);
2083 
2084 	ASSERT(vdc != NULL);
2085 	ASSERT(mutex_owned(&vdc->lock));
2086 	ASSERT(vdc->ldc_handle != NULL);
2087 
2088 	/* ensure we have enough room to store max sized block */
2089 	ASSERT(maxphys <= VD_MAX_BLOCK_SIZE);
2090 
2091 	if ((vdc->initialized & VDC_DRING_INIT) == 0) {
2092 		DMSG(vdc, 0, "[%d] ldc_mem_dring_create\n", vdc->instance);
2093 		/*
2094 		 * Calculate the maximum block size we can transmit using one
2095 		 * Descriptor Ring entry from the attributes returned by the
2096 		 * vDisk server. This is subject to a minimum of 'maxphys'
2097 		 * as we do not have the capability to split requests over
2098 		 * multiple DRing entries.
2099 		 */
2100 		if ((vdc->max_xfer_sz * vdc->block_size) < maxphys) {
2101 			DMSG(vdc, 0, "[%d] using minimum DRing size\n",
2102 					vdc->instance);
2103 			vdc->dring_max_cookies = maxphys / PAGESIZE;
2104 		} else {
2105 			vdc->dring_max_cookies =
2106 				(vdc->max_xfer_sz * vdc->block_size) / PAGESIZE;
2107 		}
2108 		vdc->dring_entry_size = (sizeof (vd_dring_entry_t) +
2109 				(sizeof (ldc_mem_cookie_t) *
2110 					(vdc->dring_max_cookies - 1)));
2111 		vdc->dring_len = VD_DRING_LEN;
2112 
2113 		status = ldc_mem_dring_create(vdc->dring_len,
2114 				vdc->dring_entry_size, &vdc->ldc_dring_hdl);
2115 		if ((vdc->ldc_dring_hdl == NULL) || (status != 0)) {
2116 			DMSG(vdc, 0, "[%d] Descriptor ring creation failed",
2117 					vdc->instance);
2118 			return (status);
2119 		}
2120 		vdc->initialized |= VDC_DRING_INIT;
2121 	}
2122 
2123 	if ((vdc->initialized & VDC_DRING_BOUND) == 0) {
2124 		DMSG(vdc, 0, "[%d] ldc_mem_dring_bind\n", vdc->instance);
2125 		vdc->dring_cookie =
2126 			kmem_zalloc(sizeof (ldc_mem_cookie_t), KM_SLEEP);
2127 
2128 		status = ldc_mem_dring_bind(vdc->ldc_handle, vdc->ldc_dring_hdl,
2129 				LDC_SHADOW_MAP|LDC_DIRECT_MAP, LDC_MEM_RW,
2130 				&vdc->dring_cookie[0],
2131 				&vdc->dring_cookie_count);
2132 		if (status != 0) {
2133 			DMSG(vdc, 0, "[%d] Failed to bind descriptor ring "
2134 				"(%lx) to channel (%lx) status=%d\n",
2135 				vdc->instance, vdc->ldc_dring_hdl,
2136 				vdc->ldc_handle, status);
2137 			return (status);
2138 		}
2139 		ASSERT(vdc->dring_cookie_count == 1);
2140 		vdc->initialized |= VDC_DRING_BOUND;
2141 	}
2142 
2143 	status = ldc_mem_dring_info(vdc->ldc_dring_hdl, &vdc->dring_mem_info);
2144 	if (status != 0) {
2145 		DMSG(vdc, 0,
2146 		    "[%d] Failed to get info for descriptor ring (%lx)\n",
2147 		    vdc->instance, vdc->ldc_dring_hdl);
2148 		return (status);
2149 	}
2150 
2151 	if ((vdc->initialized & VDC_DRING_LOCAL) == 0) {
2152 		DMSG(vdc, 0, "[%d] local dring\n", vdc->instance);
2153 
2154 		/* Allocate the local copy of this dring */
2155 		vdc->local_dring =
2156 			kmem_zalloc(vdc->dring_len * sizeof (vdc_local_desc_t),
2157 						KM_SLEEP);
2158 		vdc->initialized |= VDC_DRING_LOCAL;
2159 	}
2160 
2161 	/*
2162 	 * Mark all DRing entries as free and initialize the private
2163 	 * descriptor's memory handles. If any entry is initialized,
2164 	 * we need to free it later so we set the bit in 'initialized'
2165 	 * at the start.
2166 	 */
2167 	vdc->initialized |= VDC_DRING_ENTRY;
2168 	for (i = 0; i < vdc->dring_len; i++) {
2169 		dep = VDC_GET_DRING_ENTRY_PTR(vdc, i);
2170 		dep->hdr.dstate = VIO_DESC_FREE;
2171 
2172 		status = ldc_mem_alloc_handle(vdc->ldc_handle,
2173 				&vdc->local_dring[i].desc_mhdl);
2174 		if (status != 0) {
2175 			DMSG(vdc, 0, "![%d] Failed to alloc mem handle for"
2176 					" descriptor %d", vdc->instance, i);
2177 			return (status);
2178 		}
2179 		vdc->local_dring[i].is_free = B_TRUE;
2180 		vdc->local_dring[i].dep = dep;
2181 	}
2182 
2183 	/* Initialize the starting index */
2184 	vdc->dring_curr_idx = 0;
2185 
2186 	return (status);
2187 }
2188 
2189 /*
2190  * Function:
2191  *	vdc_destroy_descriptor_ring()
2192  *
2193  * Description:
2194  *
2195  * Arguments:
2196  *	vdc	- soft state pointer for this instance of the device driver.
2197  *
2198  * Return Code:
2199  *	None
2200  */
2201 static void
2202 vdc_destroy_descriptor_ring(vdc_t *vdc)
2203 {
2204 	vdc_local_desc_t	*ldep = NULL;	/* Local Dring Entry Pointer */
2205 	ldc_mem_handle_t	mhdl = NULL;
2206 	ldc_mem_info_t		minfo;
2207 	int			status = -1;
2208 	int			i;	/* loop */
2209 
2210 	ASSERT(vdc != NULL);
2211 	ASSERT(mutex_owned(&vdc->lock));
2212 
2213 	DMSG(vdc, 0, "[%d] Entered\n", vdc->instance);
2214 
2215 	if (vdc->initialized & VDC_DRING_ENTRY) {
2216 		DMSG(vdc, 0,
2217 		    "[%d] Removing Local DRing entries\n", vdc->instance);
2218 		for (i = 0; i < vdc->dring_len; i++) {
2219 			ldep = &vdc->local_dring[i];
2220 			mhdl = ldep->desc_mhdl;
2221 
2222 			if (mhdl == NULL)
2223 				continue;
2224 
2225 			if ((status = ldc_mem_info(mhdl, &minfo)) != 0) {
2226 				DMSG(vdc, 0,
2227 				    "ldc_mem_info returned an error: %d\n",
2228 				    status);
2229 
2230 				/*
2231 				 * This must mean that the mem handle
2232 				 * is not valid. Clear it out so that
2233 				 * no one tries to use it.
2234 				 */
2235 				ldep->desc_mhdl = NULL;
2236 				continue;
2237 			}
2238 
2239 			if (minfo.status == LDC_BOUND) {
2240 				(void) ldc_mem_unbind_handle(mhdl);
2241 			}
2242 
2243 			(void) ldc_mem_free_handle(mhdl);
2244 
2245 			ldep->desc_mhdl = NULL;
2246 		}
2247 		vdc->initialized &= ~VDC_DRING_ENTRY;
2248 	}
2249 
2250 	if (vdc->initialized & VDC_DRING_LOCAL) {
2251 		DMSG(vdc, 0, "[%d] Freeing Local DRing\n", vdc->instance);
2252 		kmem_free(vdc->local_dring,
2253 				vdc->dring_len * sizeof (vdc_local_desc_t));
2254 		vdc->initialized &= ~VDC_DRING_LOCAL;
2255 	}
2256 
2257 	if (vdc->initialized & VDC_DRING_BOUND) {
2258 		DMSG(vdc, 0, "[%d] Unbinding DRing\n", vdc->instance);
2259 		status = ldc_mem_dring_unbind(vdc->ldc_dring_hdl);
2260 		if (status == 0) {
2261 			vdc->initialized &= ~VDC_DRING_BOUND;
2262 		} else {
2263 			DMSG(vdc, 0, "[%d] Error %d unbinding DRing %lx",
2264 				vdc->instance, status, vdc->ldc_dring_hdl);
2265 		}
2266 		kmem_free(vdc->dring_cookie, sizeof (ldc_mem_cookie_t));
2267 	}
2268 
2269 	if (vdc->initialized & VDC_DRING_INIT) {
2270 		DMSG(vdc, 0, "[%d] Destroying DRing\n", vdc->instance);
2271 		status = ldc_mem_dring_destroy(vdc->ldc_dring_hdl);
2272 		if (status == 0) {
2273 			vdc->ldc_dring_hdl = NULL;
2274 			bzero(&vdc->dring_mem_info, sizeof (ldc_mem_info_t));
2275 			vdc->initialized &= ~VDC_DRING_INIT;
2276 		} else {
2277 			DMSG(vdc, 0, "[%d] Error %d destroying DRing (%lx)",
2278 				vdc->instance, status, vdc->ldc_dring_hdl);
2279 		}
2280 	}
2281 }
2282 
2283 /*
2284  * Function:
2285  *	vdc_map_to_shared_ring()
2286  *
2287  * Description:
2288  *	Copy contents of the local descriptor to the shared
2289  *	memory descriptor.
2290  *
2291  * Arguments:
2292  *	vdcp	- soft state pointer for this instance of the device driver.
2293  *	idx	- descriptor ring index
2294  *
2295  * Return Code:
2296  *	None
2297  */
2298 static int
2299 vdc_map_to_shared_dring(vdc_t *vdcp, int idx)
2300 {
2301 	vdc_local_desc_t	*ldep;
2302 	vd_dring_entry_t	*dep;
2303 	int			rv;
2304 
2305 	ldep = &(vdcp->local_dring[idx]);
2306 
2307 	/* for now leave in the old pop_mem_hdl stuff */
2308 	if (ldep->nbytes > 0) {
2309 		rv = vdc_populate_mem_hdl(vdcp, ldep);
2310 		if (rv) {
2311 			DMSG(vdcp, 0, "[%d] Cannot populate mem handle\n",
2312 			    vdcp->instance);
2313 			return (rv);
2314 		}
2315 	}
2316 
2317 	/*
2318 	 * fill in the data details into the DRing
2319 	 */
2320 	dep = ldep->dep;
2321 	ASSERT(dep != NULL);
2322 
2323 	dep->payload.req_id = VDC_GET_NEXT_REQ_ID(vdcp);
2324 	dep->payload.operation = ldep->operation;
2325 	dep->payload.addr = ldep->offset;
2326 	dep->payload.nbytes = ldep->nbytes;
2327 	dep->payload.status = (uint32_t)-1;	/* vds will set valid value */
2328 	dep->payload.slice = ldep->slice;
2329 	dep->hdr.dstate = VIO_DESC_READY;
2330 	dep->hdr.ack = 1;		/* request an ACK for every message */
2331 
2332 	return (0);
2333 }
2334 
2335 /*
2336  * Function:
2337  *	vdc_send_request
2338  *
2339  * Description:
2340  *	This routine writes the data to be transmitted to vds into the
2341  *	descriptor, notifies vds that the ring has been updated and
2342  *	then waits for the request to be processed.
2343  *
2344  * Arguments:
2345  *	vdcp	  - the soft state pointer
2346  *	operation - operation we want vds to perform (VD_OP_XXX)
2347  *	addr	  - address of data buf to be read/written.
2348  *	nbytes	  - number of bytes to read/write
2349  *	slice	  - the disk slice this request is for
2350  *	offset	  - relative disk offset
2351  *	cb_type   - type of call - STRATEGY or SYNC
2352  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2353  *			. mode for ioctl(9e)
2354  *			. LP64 diskaddr_t (block I/O)
2355  *	dir	  - direction of operation (READ/WRITE/BOTH)
2356  *
2357  * Return Codes:
2358  *	0
2359  *	ENXIO
2360  */
2361 static int
2362 vdc_send_request(vdc_t *vdcp, int operation, caddr_t addr,
2363     size_t nbytes, int slice, diskaddr_t offset, int cb_type,
2364     void *cb_arg, vio_desc_direction_t dir)
2365 {
2366 	ASSERT(vdcp != NULL);
2367 	ASSERT(slice < V_NUMPAR);
2368 
2369 	mutex_enter(&vdcp->lock);
2370 
2371 	do {
2372 		while (vdcp->state != VDC_STATE_RUNNING) {
2373 			cv_wait(&vdcp->running_cv, &vdcp->lock);
2374 
2375 			/* return error if detaching */
2376 			if (vdcp->state == VDC_STATE_DETACH) {
2377 				mutex_exit(&vdcp->lock);
2378 				return (ENXIO);
2379 			}
2380 		}
2381 
2382 	} while (vdc_populate_descriptor(vdcp, operation, addr,
2383 	    nbytes, slice, offset, cb_type, cb_arg, dir));
2384 
2385 	mutex_exit(&vdcp->lock);
2386 	return (0);
2387 }
2388 
2389 
2390 /*
2391  * Function:
2392  *	vdc_populate_descriptor
2393  *
2394  * Description:
2395  *	This routine writes the data to be transmitted to vds into the
2396  *	descriptor, notifies vds that the ring has been updated and
2397  *	then waits for the request to be processed.
2398  *
2399  * Arguments:
2400  *	vdcp	  - the soft state pointer
2401  *	operation - operation we want vds to perform (VD_OP_XXX)
2402  *	addr	  - address of data buf to be read/written.
2403  *	nbytes	  - number of bytes to read/write
2404  *	slice	  - the disk slice this request is for
2405  *	offset	  - relative disk offset
2406  *	cb_type   - type of call - STRATEGY or SYNC
2407  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2408  *			. mode for ioctl(9e)
2409  *			. LP64 diskaddr_t (block I/O)
2410  *	dir	  - direction of operation (READ/WRITE/BOTH)
2411  *
2412  * Return Codes:
2413  *	0
2414  *	EAGAIN
2415  *		EFAULT
2416  *		ENXIO
2417  *		EIO
2418  */
2419 static int
2420 vdc_populate_descriptor(vdc_t *vdcp, int operation, caddr_t addr,
2421     size_t nbytes, int slice, diskaddr_t offset, int cb_type,
2422     void *cb_arg, vio_desc_direction_t dir)
2423 {
2424 	vdc_local_desc_t	*local_dep = NULL; /* Local Dring Pointer */
2425 	int			idx;		/* Index of DRing entry used */
2426 	int			next_idx;
2427 	vio_dring_msg_t		dmsg;
2428 	size_t			msglen;
2429 	int			rv;
2430 
2431 	ASSERT(MUTEX_HELD(&vdcp->lock));
2432 	vdcp->threads_pending++;
2433 loop:
2434 	DMSG(vdcp, 2, ": dring_curr_idx = %d\n", vdcp->dring_curr_idx);
2435 
2436 	/* Get next available D-Ring entry */
2437 	idx = vdcp->dring_curr_idx;
2438 	local_dep = &(vdcp->local_dring[idx]);
2439 
2440 	if (!local_dep->is_free) {
2441 		DMSG(vdcp, 2, "[%d]: dring full - waiting for space\n",
2442 		    vdcp->instance);
2443 		cv_wait(&vdcp->dring_free_cv, &vdcp->lock);
2444 		if (vdcp->state == VDC_STATE_RUNNING ||
2445 		    vdcp->state == VDC_STATE_HANDLE_PENDING) {
2446 			goto loop;
2447 		}
2448 		vdcp->threads_pending--;
2449 		return (ECONNRESET);
2450 	}
2451 
2452 	next_idx = idx + 1;
2453 	if (next_idx >= vdcp->dring_len)
2454 		next_idx = 0;
2455 	vdcp->dring_curr_idx = next_idx;
2456 
2457 	ASSERT(local_dep->is_free);
2458 
2459 	local_dep->operation = operation;
2460 	local_dep->addr = addr;
2461 	local_dep->nbytes = nbytes;
2462 	local_dep->slice = slice;
2463 	local_dep->offset = offset;
2464 	local_dep->cb_type = cb_type;
2465 	local_dep->cb_arg = cb_arg;
2466 	local_dep->dir = dir;
2467 
2468 	local_dep->is_free = B_FALSE;
2469 
2470 	rv = vdc_map_to_shared_dring(vdcp, idx);
2471 	if (rv) {
2472 		DMSG(vdcp, 0, "[%d]: cannot bind memory - waiting ..\n",
2473 		    vdcp->instance);
2474 		/* free the descriptor */
2475 		local_dep->is_free = B_TRUE;
2476 		vdcp->dring_curr_idx = idx;
2477 		cv_wait(&vdcp->membind_cv, &vdcp->lock);
2478 		if (vdcp->state == VDC_STATE_RUNNING ||
2479 		    vdcp->state == VDC_STATE_HANDLE_PENDING) {
2480 			goto loop;
2481 		}
2482 		vdcp->threads_pending--;
2483 		return (ECONNRESET);
2484 	}
2485 
2486 	/*
2487 	 * Send a msg with the DRing details to vds
2488 	 */
2489 	VIO_INIT_DRING_DATA_TAG(dmsg);
2490 	VDC_INIT_DRING_DATA_MSG_IDS(dmsg, vdcp);
2491 	dmsg.dring_ident = vdcp->dring_ident;
2492 	dmsg.start_idx = idx;
2493 	dmsg.end_idx = idx;
2494 	vdcp->seq_num++;
2495 
2496 	DTRACE_IO2(send, vio_dring_msg_t *, &dmsg, vdc_t *, vdcp);
2497 
2498 	DMSG(vdcp, 2, "ident=0x%lx, st=%u, end=%u, seq=%ld\n",
2499 	    vdcp->dring_ident, dmsg.start_idx, dmsg.end_idx, dmsg.seq_num);
2500 
2501 	/*
2502 	 * note we're still holding the lock here to
2503 	 * make sure the message goes out in order !!!...
2504 	 */
2505 	msglen = sizeof (dmsg);
2506 	rv = vdc_send(vdcp, (caddr_t)&dmsg, &msglen);
2507 	switch (rv) {
2508 	case ECONNRESET:
2509 		/*
2510 		 * vdc_send initiates the reset on failure.
2511 		 * Since the transaction has already been put
2512 		 * on the local dring, it will automatically get
2513 		 * retried when the channel is reset. Given that,
2514 		 * it is ok to just return success even though the
2515 		 * send failed.
2516 		 */
2517 		rv = 0;
2518 		break;
2519 
2520 	case 0: /* EOK */
2521 		DMSG(vdcp, 1, "sent via LDC: rv=%d\n", rv);
2522 		break;
2523 
2524 	default:
2525 		goto cleanup_and_exit;
2526 	}
2527 
2528 	vdcp->threads_pending--;
2529 	return (rv);
2530 
2531 cleanup_and_exit:
2532 	DMSG(vdcp, 0, "unexpected error, rv=%d\n", rv);
2533 	return (ENXIO);
2534 }
2535 
2536 /*
2537  * Function:
2538  *	vdc_do_sync_op
2539  *
2540  * Description:
2541  * 	Wrapper around vdc_populate_descriptor that blocks until the
2542  * 	response to the message is available.
2543  *
2544  * Arguments:
2545  *	vdcp	  - the soft state pointer
2546  *	operation - operation we want vds to perform (VD_OP_XXX)
2547  *	addr	  - address of data buf to be read/written.
2548  *	nbytes	  - number of bytes to read/write
2549  *	slice	  - the disk slice this request is for
2550  *	offset	  - relative disk offset
2551  *	cb_type   - type of call - STRATEGY or SYNC
2552  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2553  *			. mode for ioctl(9e)
2554  *			. LP64 diskaddr_t (block I/O)
2555  *	dir	  - direction of operation (READ/WRITE/BOTH)
2556  *
2557  * Return Codes:
2558  *	0
2559  *	EAGAIN
2560  *		EFAULT
2561  *		ENXIO
2562  *		EIO
2563  */
2564 static int
2565 vdc_do_sync_op(vdc_t *vdcp, int operation, caddr_t addr, size_t nbytes,
2566     int slice, diskaddr_t offset, int cb_type, void *cb_arg,
2567     vio_desc_direction_t dir)
2568 {
2569 	int status;
2570 
2571 	ASSERT(cb_type == CB_SYNC);
2572 
2573 	/*
2574 	 * Grab the lock, if blocked wait until the server
2575 	 * response causes us to wake up again.
2576 	 */
2577 	mutex_enter(&vdcp->lock);
2578 	vdcp->sync_op_cnt++;
2579 	while (vdcp->sync_op_blocked && vdcp->state != VDC_STATE_DETACH)
2580 		cv_wait(&vdcp->sync_blocked_cv, &vdcp->lock);
2581 
2582 	if (vdcp->state == VDC_STATE_DETACH) {
2583 		cv_broadcast(&vdcp->sync_blocked_cv);
2584 		vdcp->sync_op_cnt--;
2585 		mutex_exit(&vdcp->lock);
2586 		return (ENXIO);
2587 	}
2588 
2589 	/* now block anyone other thread entering after us */
2590 	vdcp->sync_op_blocked = B_TRUE;
2591 	vdcp->sync_op_pending = B_TRUE;
2592 	mutex_exit(&vdcp->lock);
2593 
2594 	/*
2595 	 * No need to check return value - will return error only
2596 	 * in the DETACH case and we can fall through
2597 	 */
2598 	(void) vdc_send_request(vdcp, operation, addr,
2599 	    nbytes, slice, offset, cb_type, cb_arg, dir);
2600 
2601 	/*
2602 	 * block until our transaction completes.
2603 	 * Also anyone else waiting also gets to go next.
2604 	 */
2605 	mutex_enter(&vdcp->lock);
2606 	while (vdcp->sync_op_pending && vdcp->state != VDC_STATE_DETACH)
2607 		cv_wait(&vdcp->sync_pending_cv, &vdcp->lock);
2608 
2609 	DMSG(vdcp, 2, ": operation returned %d\n", vdcp->sync_op_status);
2610 	if (vdcp->state == VDC_STATE_DETACH) {
2611 		vdcp->sync_op_pending = B_FALSE;
2612 		status = ENXIO;
2613 	} else {
2614 		status = vdcp->sync_op_status;
2615 	}
2616 
2617 	vdcp->sync_op_status = 0;
2618 	vdcp->sync_op_blocked = B_FALSE;
2619 	vdcp->sync_op_cnt--;
2620 
2621 	/* signal the next waiting thread */
2622 	cv_signal(&vdcp->sync_blocked_cv);
2623 	mutex_exit(&vdcp->lock);
2624 
2625 	return (status);
2626 }
2627 
2628 
2629 /*
2630  * Function:
2631  *	vdc_drain_response()
2632  *
2633  * Description:
2634  * 	When a guest is panicking, the completion of requests needs to be
2635  * 	handled differently because interrupts are disabled and vdc
2636  * 	will not get messages. We have to poll for the messages instead.
2637  *
2638  * Arguments:
2639  *	vdc	- soft state pointer for this instance of the device driver.
2640  *
2641  * Return Code:
2642  *	0	- Success
2643  */
2644 static int
2645 vdc_drain_response(vdc_t *vdc)
2646 {
2647 	int 			rv, idx, retries;
2648 	size_t			msglen;
2649 	vdc_local_desc_t 	*ldep = NULL;	/* Local Dring Entry Pointer */
2650 	vio_dring_msg_t		dmsg;
2651 
2652 	mutex_enter(&vdc->lock);
2653 
2654 	retries = 0;
2655 	for (;;) {
2656 		msglen = sizeof (dmsg);
2657 		rv = ldc_read(vdc->ldc_handle, (caddr_t)&dmsg, &msglen);
2658 		if (rv) {
2659 			rv = EINVAL;
2660 			break;
2661 		}
2662 
2663 		/*
2664 		 * if there are no packets wait and check again
2665 		 */
2666 		if ((rv == 0) && (msglen == 0)) {
2667 			if (retries++ > vdc_dump_retries) {
2668 				rv = EAGAIN;
2669 				break;
2670 			}
2671 
2672 			drv_usecwait(vdc_usec_timeout_dump);
2673 			continue;
2674 		}
2675 
2676 		/*
2677 		 * Ignore all messages that are not ACKs/NACKs to
2678 		 * DRing requests.
2679 		 */
2680 		if ((dmsg.tag.vio_msgtype != VIO_TYPE_DATA) ||
2681 		    (dmsg.tag.vio_subtype_env != VIO_DRING_DATA)) {
2682 			DMSG(vdc, 0, "discard pkt: type=%d sub=%d env=%d\n",
2683 			    dmsg.tag.vio_msgtype,
2684 			    dmsg.tag.vio_subtype,
2685 			    dmsg.tag.vio_subtype_env);
2686 			continue;
2687 		}
2688 
2689 		/*
2690 		 * set the appropriate return value for the current request.
2691 		 */
2692 		switch (dmsg.tag.vio_subtype) {
2693 		case VIO_SUBTYPE_ACK:
2694 			rv = 0;
2695 			break;
2696 		case VIO_SUBTYPE_NACK:
2697 			rv = EAGAIN;
2698 			break;
2699 		default:
2700 			continue;
2701 		}
2702 
2703 		idx = dmsg.start_idx;
2704 		if (idx >= vdc->dring_len) {
2705 			DMSG(vdc, 0, "[%d] Bogus ack data : start %d\n",
2706 			    vdc->instance, idx);
2707 			continue;
2708 		}
2709 		ldep = &vdc->local_dring[idx];
2710 		if (ldep->dep->hdr.dstate != VIO_DESC_DONE) {
2711 			DMSG(vdc, 0, "[%d] Entry @ %d - state !DONE %d\n",
2712 			    vdc->instance, idx, ldep->dep->hdr.dstate);
2713 			continue;
2714 		}
2715 
2716 		DMSG(vdc, 1, "[%d] Depopulating idx=%d state=%d\n",
2717 		    vdc->instance, idx, ldep->dep->hdr.dstate);
2718 		rv = vdc_depopulate_descriptor(vdc, idx);
2719 		if (rv) {
2720 			DMSG(vdc, 0,
2721 			    "[%d] Entry @ %d - depopulate failed ..\n",
2722 			    vdc->instance, idx);
2723 		}
2724 
2725 		/* if this is the last descriptor - break out of loop */
2726 		if ((idx + 1) % vdc->dring_len == vdc->dring_curr_idx)
2727 			break;
2728 	}
2729 
2730 	mutex_exit(&vdc->lock);
2731 	DMSG(vdc, 0, "End idx=%d\n", idx);
2732 
2733 	return (rv);
2734 }
2735 
2736 
2737 /*
2738  * Function:
2739  *	vdc_depopulate_descriptor()
2740  *
2741  * Description:
2742  *
2743  * Arguments:
2744  *	vdc	- soft state pointer for this instance of the device driver.
2745  *	idx	- Index of the Descriptor Ring entry being modified
2746  *
2747  * Return Code:
2748  *	0	- Success
2749  */
2750 static int
2751 vdc_depopulate_descriptor(vdc_t *vdc, uint_t idx)
2752 {
2753 	vd_dring_entry_t *dep = NULL;		/* Dring Entry Pointer */
2754 	vdc_local_desc_t *ldep = NULL;		/* Local Dring Entry Pointer */
2755 	int		status = ENXIO;
2756 	int		rv = 0;
2757 
2758 	ASSERT(vdc != NULL);
2759 	ASSERT(idx < vdc->dring_len);
2760 	ldep = &vdc->local_dring[idx];
2761 	ASSERT(ldep != NULL);
2762 	ASSERT(MUTEX_HELD(&vdc->lock));
2763 
2764 	DMSG(vdc, 2, ": idx = %d\n", idx);
2765 	dep = ldep->dep;
2766 	ASSERT(dep != NULL);
2767 	ASSERT((dep->hdr.dstate == VIO_DESC_DONE) ||
2768 			(dep->payload.status == ECANCELED));
2769 
2770 	VDC_MARK_DRING_ENTRY_FREE(vdc, idx);
2771 
2772 	ldep->is_free = B_TRUE;
2773 	DMSG(vdc, 2, ": is_free = %d\n", ldep->is_free);
2774 	status = dep->payload.status;
2775 
2776 	/*
2777 	 * If no buffers were used to transfer information to the server when
2778 	 * populating the descriptor then no memory handles need to be unbound
2779 	 * and we can return now.
2780 	 */
2781 	if (ldep->nbytes == 0) {
2782 		cv_signal(&vdc->dring_free_cv);
2783 		return (status);
2784 	}
2785 
2786 	/*
2787 	 * If the upper layer passed in a misaligned address we copied the
2788 	 * data into an aligned buffer before sending it to LDC - we now
2789 	 * copy it back to the original buffer.
2790 	 */
2791 	if (ldep->align_addr) {
2792 		ASSERT(ldep->addr != NULL);
2793 
2794 		if (dep->payload.nbytes > 0)
2795 			bcopy(ldep->align_addr, ldep->addr,
2796 			    dep->payload.nbytes);
2797 		kmem_free(ldep->align_addr,
2798 			sizeof (caddr_t) * P2ROUNDUP(ldep->nbytes, 8));
2799 		ldep->align_addr = NULL;
2800 	}
2801 
2802 	rv = ldc_mem_unbind_handle(ldep->desc_mhdl);
2803 	if (rv != 0) {
2804 		DMSG(vdc, 0, "?[%d] unbind mhdl 0x%lx @ idx %d failed (%d)",
2805 				vdc->instance, ldep->desc_mhdl, idx, rv);
2806 		/*
2807 		 * The error returned by the vDisk server is more informative
2808 		 * and thus has a higher priority but if it isn't set we ensure
2809 		 * that this function returns an error.
2810 		 */
2811 		if (status == 0)
2812 			status = EINVAL;
2813 	}
2814 
2815 	cv_signal(&vdc->membind_cv);
2816 	cv_signal(&vdc->dring_free_cv);
2817 
2818 	return (status);
2819 }
2820 
2821 /*
2822  * Function:
2823  *	vdc_populate_mem_hdl()
2824  *
2825  * Description:
2826  *
2827  * Arguments:
2828  *	vdc	- soft state pointer for this instance of the device driver.
2829  *	idx	- Index of the Descriptor Ring entry being modified
2830  *	addr	- virtual address being mapped in
2831  *	nybtes	- number of bytes in 'addr'
2832  *	operation - the vDisk operation being performed (VD_OP_xxx)
2833  *
2834  * Return Code:
2835  *	0	- Success
2836  */
2837 static int
2838 vdc_populate_mem_hdl(vdc_t *vdcp, vdc_local_desc_t *ldep)
2839 {
2840 	vd_dring_entry_t	*dep = NULL;
2841 	ldc_mem_handle_t	mhdl;
2842 	caddr_t			vaddr;
2843 	size_t			nbytes;
2844 	uint8_t			perm = LDC_MEM_RW;
2845 	uint8_t			maptype;
2846 	int			rv = 0;
2847 	int			i;
2848 
2849 	ASSERT(vdcp != NULL);
2850 
2851 	dep = ldep->dep;
2852 	mhdl = ldep->desc_mhdl;
2853 
2854 	switch (ldep->dir) {
2855 	case VIO_read_dir:
2856 		perm = LDC_MEM_W;
2857 		break;
2858 
2859 	case VIO_write_dir:
2860 		perm = LDC_MEM_R;
2861 		break;
2862 
2863 	case VIO_both_dir:
2864 		perm = LDC_MEM_RW;
2865 		break;
2866 
2867 	default:
2868 		ASSERT(0);	/* catch bad programming in vdc */
2869 	}
2870 
2871 	/*
2872 	 * LDC expects any addresses passed in to be 8-byte aligned. We need
2873 	 * to copy the contents of any misaligned buffers to a newly allocated
2874 	 * buffer and bind it instead (and copy the the contents back to the
2875 	 * original buffer passed in when depopulating the descriptor)
2876 	 */
2877 	vaddr = ldep->addr;
2878 	nbytes = ldep->nbytes;
2879 	if (((uint64_t)vaddr & 0x7) != 0) {
2880 		ASSERT(ldep->align_addr == NULL);
2881 		ldep->align_addr =
2882 			kmem_alloc(sizeof (caddr_t) *
2883 				P2ROUNDUP(nbytes, 8), KM_SLEEP);
2884 		DMSG(vdcp, 0, "[%d] Misaligned address %p reallocating "
2885 		    "(buf=%p nb=%ld op=%d)\n",
2886 		    vdcp->instance, (void *)vaddr, (void *)ldep->align_addr,
2887 		    nbytes, ldep->operation);
2888 		if (perm != LDC_MEM_W)
2889 			bcopy(vaddr, ldep->align_addr, nbytes);
2890 		vaddr = ldep->align_addr;
2891 	}
2892 
2893 	maptype = LDC_IO_MAP|LDC_SHADOW_MAP|LDC_DIRECT_MAP;
2894 	rv = ldc_mem_bind_handle(mhdl, vaddr, P2ROUNDUP(nbytes, 8),
2895 		maptype, perm, &dep->payload.cookie[0],
2896 		&dep->payload.ncookies);
2897 	DMSG(vdcp, 2, "[%d] bound mem handle; ncookies=%d\n",
2898 			vdcp->instance, dep->payload.ncookies);
2899 	if (rv != 0) {
2900 		DMSG(vdcp, 0, "[%d] Failed to bind LDC memory handle "
2901 		    "(mhdl=%p, buf=%p, err=%d)\n",
2902 		    vdcp->instance, (void *)mhdl, (void *)vaddr, rv);
2903 		if (ldep->align_addr) {
2904 			kmem_free(ldep->align_addr,
2905 				sizeof (caddr_t) * P2ROUNDUP(nbytes, 8));
2906 			ldep->align_addr = NULL;
2907 		}
2908 		return (EAGAIN);
2909 	}
2910 
2911 	/*
2912 	 * Get the other cookies (if any).
2913 	 */
2914 	for (i = 1; i < dep->payload.ncookies; i++) {
2915 		rv = ldc_mem_nextcookie(mhdl, &dep->payload.cookie[i]);
2916 		if (rv != 0) {
2917 			(void) ldc_mem_unbind_handle(mhdl);
2918 			DMSG(vdcp, 0, "?[%d] Failed to get next cookie "
2919 					"(mhdl=%lx cnum=%d), err=%d",
2920 					vdcp->instance, mhdl, i, rv);
2921 			if (ldep->align_addr) {
2922 				kmem_free(ldep->align_addr,
2923 					sizeof (caddr_t) * ldep->nbytes);
2924 				ldep->align_addr = NULL;
2925 			}
2926 			return (EAGAIN);
2927 		}
2928 	}
2929 
2930 	return (rv);
2931 }
2932 
2933 /*
2934  * Interrupt handlers for messages from LDC
2935  */
2936 
2937 /*
2938  * Function:
2939  *	vdc_handle_cb()
2940  *
2941  * Description:
2942  *
2943  * Arguments:
2944  *	event	- Type of event (LDC_EVT_xxx) that triggered the callback
2945  *	arg	- soft state pointer for this instance of the device driver.
2946  *
2947  * Return Code:
2948  *	0	- Success
2949  */
2950 static uint_t
2951 vdc_handle_cb(uint64_t event, caddr_t arg)
2952 {
2953 	ldc_status_t	ldc_state;
2954 	int		rv = 0;
2955 
2956 	vdc_t	*vdc = (vdc_t *)(void *)arg;
2957 
2958 	ASSERT(vdc != NULL);
2959 
2960 	DMSG(vdc, 1, "evt=%lx seqID=%ld\n", event, vdc->seq_num);
2961 
2962 	/*
2963 	 * Depending on the type of event that triggered this callback,
2964 	 * we modify the handshake state or read the data.
2965 	 *
2966 	 * NOTE: not done as a switch() as event could be triggered by
2967 	 * a state change and a read request. Also the ordering	of the
2968 	 * check for the event types is deliberate.
2969 	 */
2970 	if (event & LDC_EVT_UP) {
2971 		DMSG(vdc, 0, "[%d] Received LDC_EVT_UP\n", vdc->instance);
2972 
2973 		mutex_enter(&vdc->lock);
2974 
2975 		/* get LDC state */
2976 		rv = ldc_status(vdc->ldc_handle, &ldc_state);
2977 		if (rv != 0) {
2978 			DMSG(vdc, 0, "[%d] Couldn't get LDC status %d",
2979 			    vdc->instance, rv);
2980 			return (LDC_SUCCESS);
2981 		}
2982 		if (vdc->ldc_state != LDC_UP && ldc_state == LDC_UP) {
2983 			/*
2984 			 * Reset the transaction sequence numbers when
2985 			 * LDC comes up. We then kick off the handshake
2986 			 * negotiation with the vDisk server.
2987 			 */
2988 			vdc->seq_num = 1;
2989 			vdc->seq_num_reply = 0;
2990 			vdc->ldc_state = ldc_state;
2991 			cv_signal(&vdc->initwait_cv);
2992 		}
2993 
2994 		mutex_exit(&vdc->lock);
2995 	}
2996 
2997 	if (event & LDC_EVT_READ) {
2998 		DMSG(vdc, 0, "[%d] Received LDC_EVT_READ\n", vdc->instance);
2999 		mutex_enter(&vdc->read_lock);
3000 		cv_signal(&vdc->read_cv);
3001 		vdc->read_state = VDC_READ_PENDING;
3002 		mutex_exit(&vdc->read_lock);
3003 
3004 		/* that's all we have to do - no need to handle DOWN/RESET */
3005 		return (LDC_SUCCESS);
3006 	}
3007 
3008 	if (event & (LDC_EVT_RESET|LDC_EVT_DOWN)) {
3009 
3010 		DMSG(vdc, 0, "[%d] Received LDC RESET event\n", vdc->instance);
3011 
3012 		mutex_enter(&vdc->lock);
3013 		/*
3014 		 * Need to wake up any readers so they will
3015 		 * detect that a reset has occurred.
3016 		 */
3017 		mutex_enter(&vdc->read_lock);
3018 		if ((vdc->read_state == VDC_READ_WAITING) ||
3019 		    (vdc->read_state == VDC_READ_RESET))
3020 			cv_signal(&vdc->read_cv);
3021 		vdc->read_state = VDC_READ_RESET;
3022 		mutex_exit(&vdc->read_lock);
3023 
3024 		/* wake up any threads waiting for connection to come up */
3025 		if (vdc->state == VDC_STATE_INIT_WAITING) {
3026 			vdc->state = VDC_STATE_RESETTING;
3027 			cv_signal(&vdc->initwait_cv);
3028 		}
3029 
3030 		mutex_exit(&vdc->lock);
3031 	}
3032 
3033 	if (event & ~(LDC_EVT_UP | LDC_EVT_RESET | LDC_EVT_DOWN | LDC_EVT_READ))
3034 		DMSG(vdc, 0, "![%d] Unexpected LDC event (%lx) received",
3035 				vdc->instance, event);
3036 
3037 	return (LDC_SUCCESS);
3038 }
3039 
3040 /*
3041  * Function:
3042  *	vdc_wait_for_response()
3043  *
3044  * Description:
3045  *	Block waiting for a response from the server. If there is
3046  *	no data the thread block on the read_cv that is signalled
3047  *	by the callback when an EVT_READ occurs.
3048  *
3049  * Arguments:
3050  *	vdcp	- soft state pointer for this instance of the device driver.
3051  *
3052  * Return Code:
3053  *	0	- Success
3054  */
3055 static int
3056 vdc_wait_for_response(vdc_t *vdcp, vio_msg_t *msgp)
3057 {
3058 	size_t		nbytes = sizeof (*msgp);
3059 	int		status;
3060 
3061 	ASSERT(vdcp != NULL);
3062 
3063 	DMSG(vdcp, 1, "[%d] Entered\n", vdcp->instance);
3064 
3065 	status = vdc_recv(vdcp, msgp, &nbytes);
3066 	DMSG(vdcp, 3, "vdc_read() done.. status=0x%x size=0x%x\n",
3067 		status, (int)nbytes);
3068 	if (status) {
3069 		DMSG(vdcp, 0, "?[%d] Error %d reading LDC msg\n",
3070 				vdcp->instance, status);
3071 		return (status);
3072 	}
3073 
3074 	if (nbytes < sizeof (vio_msg_tag_t)) {
3075 		DMSG(vdcp, 0, "?[%d] Expect %lu bytes; recv'd %lu\n",
3076 			vdcp->instance, sizeof (vio_msg_tag_t), nbytes);
3077 		return (ENOMSG);
3078 	}
3079 
3080 	DMSG(vdcp, 2, "[%d] (%x/%x/%x)\n", vdcp->instance,
3081 	    msgp->tag.vio_msgtype,
3082 	    msgp->tag.vio_subtype,
3083 	    msgp->tag.vio_subtype_env);
3084 
3085 	/*
3086 	 * Verify the Session ID of the message
3087 	 *
3088 	 * Every message after the Version has been negotiated should
3089 	 * have the correct session ID set.
3090 	 */
3091 	if ((msgp->tag.vio_sid != vdcp->session_id) &&
3092 	    (msgp->tag.vio_subtype_env != VIO_VER_INFO)) {
3093 		DMSG(vdcp, 0, "[%d] Invalid SID: received 0x%x, "
3094 				"expected 0x%lx [seq num %lx @ %d]",
3095 			vdcp->instance, msgp->tag.vio_sid,
3096 			vdcp->session_id,
3097 			((vio_dring_msg_t *)msgp)->seq_num,
3098 			((vio_dring_msg_t *)msgp)->start_idx);
3099 		return (ENOMSG);
3100 	}
3101 	return (0);
3102 }
3103 
3104 
3105 /*
3106  * Function:
3107  *	vdc_resubmit_backup_dring()
3108  *
3109  * Description:
3110  *	Resubmit each descriptor in the backed up dring to
3111  * 	vDisk server. The Dring was backed up during connection
3112  *	reset.
3113  *
3114  * Arguments:
3115  *	vdcp	- soft state pointer for this instance of the device driver.
3116  *
3117  * Return Code:
3118  *	0	- Success
3119  */
3120 static int
3121 vdc_resubmit_backup_dring(vdc_t *vdcp)
3122 {
3123 	int		count;
3124 	int		b_idx;
3125 	int		rv;
3126 	int		dring_size;
3127 	int		status;
3128 	vio_msg_t	vio_msg;
3129 	vdc_local_desc_t	*curr_ldep;
3130 
3131 	ASSERT(MUTEX_NOT_HELD(&vdcp->lock));
3132 	ASSERT(vdcp->state == VDC_STATE_HANDLE_PENDING);
3133 
3134 	DMSG(vdcp, 1, "restoring pending dring entries (len=%d, tail=%d)\n",
3135 	    vdcp->local_dring_backup_len, vdcp->local_dring_backup_tail);
3136 
3137 	/*
3138 	 * Walk the backup copy of the local descriptor ring and
3139 	 * resubmit all the outstanding transactions.
3140 	 */
3141 	b_idx = vdcp->local_dring_backup_tail;
3142 	for (count = 0; count < vdcp->local_dring_backup_len; count++) {
3143 
3144 		curr_ldep = &(vdcp->local_dring_backup[b_idx]);
3145 
3146 		/* only resubmit outstanding transactions */
3147 		if (!curr_ldep->is_free) {
3148 
3149 			DMSG(vdcp, 1, "resubmitting entry idx=%x\n", b_idx);
3150 			mutex_enter(&vdcp->lock);
3151 			rv = vdc_populate_descriptor(vdcp, curr_ldep->operation,
3152 			    curr_ldep->addr, curr_ldep->nbytes,
3153 			    curr_ldep->slice, curr_ldep->offset,
3154 			    curr_ldep->cb_type, curr_ldep->cb_arg,
3155 			    curr_ldep->dir);
3156 			mutex_exit(&vdcp->lock);
3157 			if (rv) {
3158 				DMSG(vdcp, 1, "[%d] cannot resubmit entry %d\n",
3159 				    vdcp->instance, b_idx);
3160 				return (rv);
3161 			}
3162 
3163 			/* Wait for the response message. */
3164 			DMSG(vdcp, 1, "waiting for response to idx=%x\n",
3165 			    b_idx);
3166 			status = vdc_wait_for_response(vdcp, &vio_msg);
3167 			if (status) {
3168 				DMSG(vdcp, 1, "[%d] wait_for_response "
3169 				    "returned err=%d\n", vdcp->instance,
3170 				    status);
3171 				return (status);
3172 			}
3173 
3174 			DMSG(vdcp, 1, "processing msg for idx=%x\n", b_idx);
3175 			status = vdc_process_data_msg(vdcp, &vio_msg);
3176 			if (status) {
3177 				DMSG(vdcp, 1, "[%d] process_data_msg "
3178 				    "returned err=%d\n", vdcp->instance,
3179 				    status);
3180 				return (status);
3181 			}
3182 		}
3183 
3184 		/* get the next element to submit */
3185 		if (++b_idx >= vdcp->local_dring_backup_len)
3186 			b_idx = 0;
3187 	}
3188 
3189 	/* all done - now clear up pending dring copy */
3190 	dring_size = vdcp->local_dring_backup_len *
3191 		sizeof (vdcp->local_dring_backup[0]);
3192 
3193 	(void) kmem_free(vdcp->local_dring_backup, dring_size);
3194 
3195 	vdcp->local_dring_backup = NULL;
3196 
3197 	return (0);
3198 }
3199 
3200 /*
3201  * Function:
3202  *	vdc_backup_local_dring()
3203  *
3204  * Description:
3205  *	Backup the current dring in the event of a reset. The Dring
3206  *	transactions will be resubmitted to the server when the
3207  *	connection is restored.
3208  *
3209  * Arguments:
3210  *	vdcp	- soft state pointer for this instance of the device driver.
3211  *
3212  * Return Code:
3213  *	NONE
3214  */
3215 static void
3216 vdc_backup_local_dring(vdc_t *vdcp)
3217 {
3218 	int dring_size;
3219 
3220 	ASSERT(vdcp->state == VDC_STATE_RESETTING);
3221 
3222 	/*
3223 	 * If the backup dring is stil around, it means
3224 	 * that the last restore did not complete. However,
3225 	 * since we never got back into the running state,
3226 	 * the backup copy we have is still valid.
3227 	 */
3228 	if (vdcp->local_dring_backup != NULL) {
3229 		DMSG(vdcp, 1, "reusing local descriptor ring backup "
3230 		    "(len=%d, tail=%d)\n", vdcp->local_dring_backup_len,
3231 		    vdcp->local_dring_backup_tail);
3232 		return;
3233 	}
3234 
3235 	DMSG(vdcp, 1, "backing up the local descriptor ring (len=%d, "
3236 	    "tail=%d)\n", vdcp->dring_len, vdcp->dring_curr_idx);
3237 
3238 	dring_size = vdcp->dring_len * sizeof (vdcp->local_dring[0]);
3239 
3240 	vdcp->local_dring_backup = kmem_alloc(dring_size, KM_SLEEP);
3241 	bcopy(vdcp->local_dring, vdcp->local_dring_backup, dring_size);
3242 
3243 	vdcp->local_dring_backup_tail = vdcp->dring_curr_idx;
3244 	vdcp->local_dring_backup_len = vdcp->dring_len;
3245 }
3246 
3247 /* -------------------------------------------------------------------------- */
3248 
3249 /*
3250  * The following functions process the incoming messages from vds
3251  */
3252 
3253 /*
3254  * Function:
3255  *      vdc_process_msg_thread()
3256  *
3257  * Description:
3258  *
3259  *	Main VDC message processing thread. Each vDisk instance
3260  * 	consists of a copy of this thread. This thread triggers
3261  * 	all the handshakes and data exchange with the server. It
3262  * 	also handles all channel resets
3263  *
3264  * Arguments:
3265  *      vdc     - soft state pointer for this instance of the device driver.
3266  *
3267  * Return Code:
3268  *      None
3269  */
3270 static void
3271 vdc_process_msg_thread(vdc_t *vdcp)
3272 {
3273 	int	status;
3274 
3275 	mutex_enter(&vdcp->lock);
3276 
3277 	for (;;) {
3278 
3279 #define	Q(_s)	(vdcp->state == _s) ? #_s :
3280 		DMSG(vdcp, 3, "state = %d (%s)\n", vdcp->state,
3281 		Q(VDC_STATE_INIT)
3282 		Q(VDC_STATE_INIT_WAITING)
3283 		Q(VDC_STATE_NEGOTIATE)
3284 		Q(VDC_STATE_HANDLE_PENDING)
3285 		Q(VDC_STATE_RUNNING)
3286 		Q(VDC_STATE_RESETTING)
3287 		Q(VDC_STATE_DETACH)
3288 		"UNKNOWN");
3289 
3290 		switch (vdcp->state) {
3291 		case VDC_STATE_INIT:
3292 
3293 			/* Check if have re-initializing repeatedly */
3294 			if (vdcp->hshake_cnt++ > vdc_hshake_retries) {
3295 				cmn_err(CE_NOTE, "[%d] disk access failed.\n",
3296 				    vdcp->instance);
3297 				vdcp->state = VDC_STATE_DETACH;
3298 				break;
3299 			}
3300 
3301 			/* Bring up connection with vds via LDC */
3302 			status = vdc_start_ldc_connection(vdcp);
3303 			switch (status) {
3304 			case EINVAL:
3305 				DMSG(vdcp, 0, "[%d] Could not start LDC",
3306 				    vdcp->instance);
3307 				vdcp->state = VDC_STATE_DETACH;
3308 				break;
3309 			case 0:
3310 				vdcp->state = VDC_STATE_INIT_WAITING;
3311 				break;
3312 			default:
3313 				vdcp->state = VDC_STATE_INIT_WAITING;
3314 				break;
3315 			}
3316 			break;
3317 
3318 		case VDC_STATE_INIT_WAITING:
3319 
3320 			/*
3321 			 * Let the callback event move us on
3322 			 * when channel is open to server
3323 			 */
3324 			while (vdcp->ldc_state != LDC_UP) {
3325 				cv_wait(&vdcp->initwait_cv, &vdcp->lock);
3326 				if (vdcp->state != VDC_STATE_INIT_WAITING) {
3327 					DMSG(vdcp, 0,
3328 				"state moved to %d out from under us...\n",
3329 					    vdcp->state);
3330 
3331 					break;
3332 				}
3333 			}
3334 			if (vdcp->state == VDC_STATE_INIT_WAITING &&
3335 			    vdcp->ldc_state == LDC_UP) {
3336 				vdcp->state = VDC_STATE_NEGOTIATE;
3337 			}
3338 			break;
3339 
3340 		case VDC_STATE_NEGOTIATE:
3341 			switch (status = vdc_ver_negotiation(vdcp)) {
3342 			case 0:
3343 				break;
3344 			default:
3345 				DMSG(vdcp, 0, "ver negotiate failed (%d)..\n",
3346 				    status);
3347 				goto reset;
3348 			}
3349 
3350 			switch (status = vdc_attr_negotiation(vdcp)) {
3351 			case 0:
3352 				break;
3353 			default:
3354 				DMSG(vdcp, 0, "attr negotiate failed (%d)..\n",
3355 				    status);
3356 				goto reset;
3357 			}
3358 
3359 			switch (status = vdc_dring_negotiation(vdcp)) {
3360 			case 0:
3361 				break;
3362 			default:
3363 				DMSG(vdcp, 0, "dring negotiate failed (%d)..\n",
3364 				    status);
3365 				goto reset;
3366 			}
3367 
3368 			switch (status = vdc_rdx_exchange(vdcp)) {
3369 			case 0:
3370 				vdcp->state = VDC_STATE_HANDLE_PENDING;
3371 				goto done;
3372 			default:
3373 				DMSG(vdcp, 0, "RDX xchg failed ..(%d)\n",
3374 				    status);
3375 				goto reset;
3376 			}
3377 reset:
3378 			DMSG(vdcp, 0, "negotiation failed: resetting (%d)\n",
3379 			    status);
3380 			vdcp->state = VDC_STATE_RESETTING;
3381 done:
3382 			DMSG(vdcp, 0, "negotiation complete (state=0x%x)...\n",
3383 			    vdcp->state);
3384 			break;
3385 
3386 		case VDC_STATE_HANDLE_PENDING:
3387 
3388 			mutex_exit(&vdcp->lock);
3389 			status = vdc_resubmit_backup_dring(vdcp);
3390 			mutex_enter(&vdcp->lock);
3391 
3392 			if (status)
3393 				vdcp->state = VDC_STATE_RESETTING;
3394 			else
3395 				vdcp->state = VDC_STATE_RUNNING;
3396 
3397 			break;
3398 
3399 		/* enter running state */
3400 		case VDC_STATE_RUNNING:
3401 			/*
3402 			 * Signal anyone waiting for the connection
3403 			 * to come on line.
3404 			 */
3405 			vdcp->hshake_cnt = 0;
3406 			cv_broadcast(&vdcp->running_cv);
3407 			mutex_exit(&vdcp->lock);
3408 
3409 			for (;;) {
3410 				vio_msg_t msg;
3411 				status = vdc_wait_for_response(vdcp, &msg);
3412 				if (status) break;
3413 
3414 				DMSG(vdcp, 1, "[%d] new pkt(s) available\n",
3415 					vdcp->instance);
3416 				status = vdc_process_data_msg(vdcp, &msg);
3417 				if (status) {
3418 					DMSG(vdcp, 1, "[%d] process_data_msg "
3419 					    "returned err=%d\n", vdcp->instance,
3420 					    status);
3421 					break;
3422 				}
3423 
3424 			}
3425 
3426 			mutex_enter(&vdcp->lock);
3427 
3428 			vdcp->state = VDC_STATE_RESETTING;
3429 			vdcp->self_reset = B_TRUE;
3430 			break;
3431 
3432 		case VDC_STATE_RESETTING:
3433 			DMSG(vdcp, 0, "Initiating channel reset "
3434 			    "(pending = %d)\n", (int)vdcp->threads_pending);
3435 
3436 			if (vdcp->self_reset) {
3437 				DMSG(vdcp, 0,
3438 				    "[%d] calling stop_ldc_connection.\n",
3439 				    vdcp->instance);
3440 				status = vdc_stop_ldc_connection(vdcp);
3441 				vdcp->self_reset = B_FALSE;
3442 			}
3443 
3444 			/*
3445 			 * Wait for all threads currently waiting
3446 			 * for a free dring entry to use.
3447 			 */
3448 			while (vdcp->threads_pending) {
3449 				cv_broadcast(&vdcp->membind_cv);
3450 				cv_broadcast(&vdcp->dring_free_cv);
3451 				mutex_exit(&vdcp->lock);
3452 				/* let them wake up */
3453 				drv_usecwait(vdc_min_timeout_ldc);
3454 				mutex_enter(&vdcp->lock);
3455 			}
3456 
3457 			ASSERT(vdcp->threads_pending == 0);
3458 
3459 			/* Sanity check that no thread is receiving */
3460 			ASSERT(vdcp->read_state != VDC_READ_WAITING);
3461 
3462 			vdcp->read_state = VDC_READ_IDLE;
3463 
3464 			vdc_backup_local_dring(vdcp);
3465 
3466 			/* cleanup the old d-ring */
3467 			vdc_destroy_descriptor_ring(vdcp);
3468 
3469 			/* go and start again */
3470 			vdcp->state = VDC_STATE_INIT;
3471 
3472 			break;
3473 
3474 		case VDC_STATE_DETACH:
3475 			DMSG(vdcp, 0, "[%d] Reset thread exit cleanup ..\n",
3476 			    vdcp->instance);
3477 
3478 			/*
3479 			 * Signal anyone waiting for connection
3480 			 * to come online
3481 			 */
3482 			cv_broadcast(&vdcp->running_cv);
3483 
3484 			while (vdcp->sync_op_pending) {
3485 				cv_signal(&vdcp->sync_pending_cv);
3486 				cv_signal(&vdcp->sync_blocked_cv);
3487 				mutex_exit(&vdcp->lock);
3488 				drv_usecwait(vdc_min_timeout_ldc);
3489 				mutex_enter(&vdcp->lock);
3490 			}
3491 
3492 			mutex_exit(&vdcp->lock);
3493 
3494 			DMSG(vdcp, 0, "[%d] Msg processing thread exiting ..\n",
3495 				vdcp->instance);
3496 			thread_exit();
3497 			break;
3498 		}
3499 	}
3500 }
3501 
3502 
3503 /*
3504  * Function:
3505  *	vdc_process_data_msg()
3506  *
3507  * Description:
3508  *	This function is called by the message processing thread each time
3509  *	a message with a msgtype of VIO_TYPE_DATA is received. It will either
3510  *	be an ACK or NACK from vds[1] which vdc handles as follows.
3511  *		ACK	- wake up the waiting thread
3512  *		NACK	- resend any messages necessary
3513  *
3514  *	[1] Although the message format allows it, vds should not send a
3515  *	    VIO_SUBTYPE_INFO message to vdc asking it to read data; if for
3516  *	    some bizarre reason it does, vdc will reset the connection.
3517  *
3518  * Arguments:
3519  *	vdc	- soft state pointer for this instance of the device driver.
3520  *	msg	- the LDC message sent by vds
3521  *
3522  * Return Code:
3523  *	0	- Success.
3524  *	> 0	- error value returned by LDC
3525  */
3526 static int
3527 vdc_process_data_msg(vdc_t *vdcp, vio_msg_t *msg)
3528 {
3529 	int			status = 0;
3530 	vio_dring_msg_t		*dring_msg;
3531 	vdc_local_desc_t	*ldep = NULL;
3532 	int			start, end;
3533 	int			idx;
3534 
3535 	dring_msg = (vio_dring_msg_t *)msg;
3536 
3537 	ASSERT(msg->tag.vio_msgtype == VIO_TYPE_DATA);
3538 	ASSERT(vdcp != NULL);
3539 
3540 	mutex_enter(&vdcp->lock);
3541 
3542 	/*
3543 	 * Check to see if the message has bogus data
3544 	 */
3545 	idx = start = dring_msg->start_idx;
3546 	end = dring_msg->end_idx;
3547 	if ((start >= vdcp->dring_len) ||
3548 	    (end >= vdcp->dring_len) || (end < -1)) {
3549 		DMSG(vdcp, 0, "[%d] Bogus ACK data : start %d, end %d\n",
3550 			vdcp->instance, start, end);
3551 		mutex_exit(&vdcp->lock);
3552 		return (EINVAL);
3553 	}
3554 
3555 	/*
3556 	 * Verify that the sequence number is what vdc expects.
3557 	 */
3558 	switch (vdc_verify_seq_num(vdcp, dring_msg)) {
3559 	case VDC_SEQ_NUM_TODO:
3560 		break;	/* keep processing this message */
3561 	case VDC_SEQ_NUM_SKIP:
3562 		mutex_exit(&vdcp->lock);
3563 		return (0);
3564 	case VDC_SEQ_NUM_INVALID:
3565 		mutex_exit(&vdcp->lock);
3566 		DMSG(vdcp, 0, "[%d] invalid seqno\n", vdcp->instance);
3567 		return (ENXIO);
3568 	}
3569 
3570 	if (msg->tag.vio_subtype == VIO_SUBTYPE_NACK) {
3571 		DMSG(vdcp, 0, "[%d] DATA NACK\n", vdcp->instance);
3572 		VDC_DUMP_DRING_MSG(dring_msg);
3573 		mutex_exit(&vdcp->lock);
3574 		return (EIO);
3575 
3576 	} else if (msg->tag.vio_subtype == VIO_SUBTYPE_INFO) {
3577 		mutex_exit(&vdcp->lock);
3578 		return (EPROTO);
3579 	}
3580 
3581 	DTRACE_IO2(recv, vio_dring_msg_t, dring_msg, vdc_t *, vdcp);
3582 	DMSG(vdcp, 1, ": start %d end %d\n", start, end);
3583 	ASSERT(start == end);
3584 
3585 	ldep = &vdcp->local_dring[idx];
3586 
3587 	DMSG(vdcp, 1, ": state 0x%x - cb_type 0x%x\n",
3588 		ldep->dep->hdr.dstate, ldep->cb_type);
3589 
3590 	if (ldep->dep->hdr.dstate == VIO_DESC_DONE) {
3591 		struct buf *bufp;
3592 
3593 		switch (ldep->cb_type) {
3594 		case CB_SYNC:
3595 			ASSERT(vdcp->sync_op_pending);
3596 
3597 			status = vdc_depopulate_descriptor(vdcp, idx);
3598 			vdcp->sync_op_status = status;
3599 			vdcp->sync_op_pending = B_FALSE;
3600 			cv_signal(&vdcp->sync_pending_cv);
3601 			break;
3602 
3603 		case CB_STRATEGY:
3604 			bufp = ldep->cb_arg;
3605 			ASSERT(bufp != NULL);
3606 			bufp->b_resid =
3607 				bufp->b_bcount - ldep->dep->payload.nbytes;
3608 			status = ldep->dep->payload.status; /* Future:ntoh */
3609 			if (status != 0) {
3610 				DMSG(vdcp, 1, "strategy status=%d\n", status);
3611 				bioerror(bufp, status);
3612 			}
3613 			status = vdc_depopulate_descriptor(vdcp, idx);
3614 			biodone(bufp);
3615 
3616 			DMSG(vdcp, 1,
3617 			    "strategy complete req=%ld bytes resp=%ld bytes\n",
3618 			    bufp->b_bcount, ldep->dep->payload.nbytes);
3619 			break;
3620 
3621 		default:
3622 			ASSERT(0);
3623 		}
3624 	}
3625 
3626 	/* let the arrival signal propogate */
3627 	mutex_exit(&vdcp->lock);
3628 
3629 	/* probe gives the count of how many entries were processed */
3630 	DTRACE_IO2(processed, int, 1, vdc_t *, vdcp);
3631 
3632 	return (0);
3633 }
3634 
3635 /*
3636  * Function:
3637  *	vdc_process_err_msg()
3638  *
3639  * NOTE: No error messages are used as part of the vDisk protocol
3640  */
3641 static int
3642 vdc_process_err_msg(vdc_t *vdc, vio_msg_t msg)
3643 {
3644 	_NOTE(ARGUNUSED(vdc))
3645 	_NOTE(ARGUNUSED(msg))
3646 
3647 	ASSERT(msg.tag.vio_msgtype == VIO_TYPE_ERR);
3648 	DMSG(vdc, 1, "[%d] Got an ERR msg", vdc->instance);
3649 
3650 	return (ENOTSUP);
3651 }
3652 
3653 /*
3654  * Function:
3655  *	vdc_handle_ver_msg()
3656  *
3657  * Description:
3658  *
3659  * Arguments:
3660  *	vdc	- soft state pointer for this instance of the device driver.
3661  *	ver_msg	- LDC message sent by vDisk server
3662  *
3663  * Return Code:
3664  *	0	- Success
3665  */
3666 static int
3667 vdc_handle_ver_msg(vdc_t *vdc, vio_ver_msg_t *ver_msg)
3668 {
3669 	int status = 0;
3670 
3671 	ASSERT(vdc != NULL);
3672 	ASSERT(mutex_owned(&vdc->lock));
3673 
3674 	if (ver_msg->tag.vio_subtype_env != VIO_VER_INFO) {
3675 		return (EPROTO);
3676 	}
3677 
3678 	if (ver_msg->dev_class != VDEV_DISK_SERVER) {
3679 		return (EINVAL);
3680 	}
3681 
3682 	switch (ver_msg->tag.vio_subtype) {
3683 	case VIO_SUBTYPE_ACK:
3684 		/*
3685 		 * We check to see if the version returned is indeed supported
3686 		 * (The server may have also adjusted the minor number downwards
3687 		 * and if so 'ver_msg' will contain the actual version agreed)
3688 		 */
3689 		if (vdc_is_supported_version(ver_msg)) {
3690 			vdc->ver.major = ver_msg->ver_major;
3691 			vdc->ver.minor = ver_msg->ver_minor;
3692 			ASSERT(vdc->ver.major > 0);
3693 		} else {
3694 			status = EPROTO;
3695 		}
3696 		break;
3697 
3698 	case VIO_SUBTYPE_NACK:
3699 		/*
3700 		 * call vdc_is_supported_version() which will return the next
3701 		 * supported version (if any) in 'ver_msg'
3702 		 */
3703 		(void) vdc_is_supported_version(ver_msg);
3704 		if (ver_msg->ver_major > 0) {
3705 			size_t len = sizeof (*ver_msg);
3706 
3707 			ASSERT(vdc->ver.major > 0);
3708 
3709 			/* reset the necessary fields and resend */
3710 			ver_msg->tag.vio_subtype = VIO_SUBTYPE_INFO;
3711 			ver_msg->dev_class = VDEV_DISK;
3712 
3713 			status = vdc_send(vdc, (caddr_t)ver_msg, &len);
3714 			DMSG(vdc, 0, "[%d] Resend VER info (LDC status = %d)\n",
3715 					vdc->instance, status);
3716 			if (len != sizeof (*ver_msg))
3717 				status = EBADMSG;
3718 		} else {
3719 			DMSG(vdc, 0, "[%d] No common version with "
3720 					"vDisk server", vdc->instance);
3721 			status = ENOTSUP;
3722 		}
3723 
3724 		break;
3725 	case VIO_SUBTYPE_INFO:
3726 		/*
3727 		 * Handle the case where vds starts handshake
3728 		 * (for now only vdc is the instigator)
3729 		 */
3730 		status = ENOTSUP;
3731 		break;
3732 
3733 	default:
3734 		status = EINVAL;
3735 		break;
3736 	}
3737 
3738 	return (status);
3739 }
3740 
3741 /*
3742  * Function:
3743  *	vdc_handle_attr_msg()
3744  *
3745  * Description:
3746  *
3747  * Arguments:
3748  *	vdc	- soft state pointer for this instance of the device driver.
3749  *	attr_msg	- LDC message sent by vDisk server
3750  *
3751  * Return Code:
3752  *	0	- Success
3753  */
3754 static int
3755 vdc_handle_attr_msg(vdc_t *vdc, vd_attr_msg_t *attr_msg)
3756 {
3757 	int status = 0;
3758 
3759 	ASSERT(vdc != NULL);
3760 	ASSERT(mutex_owned(&vdc->lock));
3761 
3762 	if (attr_msg->tag.vio_subtype_env != VIO_ATTR_INFO) {
3763 		return (EPROTO);
3764 	}
3765 
3766 	switch (attr_msg->tag.vio_subtype) {
3767 	case VIO_SUBTYPE_ACK:
3768 		/*
3769 		 * We now verify the attributes sent by vds.
3770 		 */
3771 		vdc->vdisk_size = attr_msg->vdisk_size;
3772 		vdc->vdisk_type = attr_msg->vdisk_type;
3773 
3774 		DMSG(vdc, 0, "[%d] max_xfer_sz: sent %lx acked %lx\n",
3775 			vdc->instance, vdc->max_xfer_sz, attr_msg->max_xfer_sz);
3776 		DMSG(vdc, 0, "[%d] vdisk_block_size: sent %lx acked %x\n",
3777 			vdc->instance, vdc->block_size,
3778 			attr_msg->vdisk_block_size);
3779 
3780 		/*
3781 		 * We don't know at compile time what the vDisk server will
3782 		 * think are good values but we apply an large (arbitrary)
3783 		 * upper bound to prevent memory exhaustion in vdc if it was
3784 		 * allocating a DRing based of huge values sent by the server.
3785 		 * We probably will never exceed this except if the message
3786 		 * was garbage.
3787 		 */
3788 		if ((attr_msg->max_xfer_sz * attr_msg->vdisk_block_size) <=
3789 				(PAGESIZE * DEV_BSIZE)) {
3790 			vdc->max_xfer_sz = attr_msg->max_xfer_sz;
3791 			vdc->block_size = attr_msg->vdisk_block_size;
3792 		} else {
3793 			DMSG(vdc, 0, "[%d] vds block transfer size too big;"
3794 				" using max supported by vdc", vdc->instance);
3795 		}
3796 
3797 		if ((attr_msg->xfer_mode != VIO_DRING_MODE) ||
3798 		    (attr_msg->vdisk_size > INT64_MAX) ||
3799 		    (attr_msg->vdisk_type > VD_DISK_TYPE_DISK)) {
3800 			DMSG(vdc, 0, "[%d] Invalid attributes from vds",
3801 					vdc->instance);
3802 			status = EINVAL;
3803 			break;
3804 		}
3805 
3806 		break;
3807 
3808 	case VIO_SUBTYPE_NACK:
3809 		/*
3810 		 * vds could not handle the attributes we sent so we
3811 		 * stop negotiating.
3812 		 */
3813 		status = EPROTO;
3814 		break;
3815 
3816 	case VIO_SUBTYPE_INFO:
3817 		/*
3818 		 * Handle the case where vds starts the handshake
3819 		 * (for now; vdc is the only supported instigatior)
3820 		 */
3821 		status = ENOTSUP;
3822 		break;
3823 
3824 	default:
3825 		status = ENOTSUP;
3826 		break;
3827 	}
3828 
3829 	return (status);
3830 }
3831 
3832 /*
3833  * Function:
3834  *	vdc_handle_dring_reg_msg()
3835  *
3836  * Description:
3837  *
3838  * Arguments:
3839  *	vdc		- soft state pointer for this instance of the driver.
3840  *	dring_msg	- LDC message sent by vDisk server
3841  *
3842  * Return Code:
3843  *	0	- Success
3844  */
3845 static int
3846 vdc_handle_dring_reg_msg(vdc_t *vdc, vio_dring_reg_msg_t *dring_msg)
3847 {
3848 	int		status = 0;
3849 
3850 	ASSERT(vdc != NULL);
3851 	ASSERT(mutex_owned(&vdc->lock));
3852 
3853 	if (dring_msg->tag.vio_subtype_env != VIO_DRING_REG) {
3854 		return (EPROTO);
3855 	}
3856 
3857 	switch (dring_msg->tag.vio_subtype) {
3858 	case VIO_SUBTYPE_ACK:
3859 		/* save the received dring_ident */
3860 		vdc->dring_ident = dring_msg->dring_ident;
3861 		DMSG(vdc, 0, "[%d] Received dring ident=0x%lx\n",
3862 			vdc->instance, vdc->dring_ident);
3863 		break;
3864 
3865 	case VIO_SUBTYPE_NACK:
3866 		/*
3867 		 * vds could not handle the DRing info we sent so we
3868 		 * stop negotiating.
3869 		 */
3870 		DMSG(vdc, 0, "[%d] server could not register DRing\n",
3871 		    vdc->instance);
3872 		status = EPROTO;
3873 		break;
3874 
3875 	case VIO_SUBTYPE_INFO:
3876 		/*
3877 		 * Handle the case where vds starts handshake
3878 		 * (for now only vdc is the instigatior)
3879 		 */
3880 		status = ENOTSUP;
3881 		break;
3882 	default:
3883 		status = ENOTSUP;
3884 	}
3885 
3886 	return (status);
3887 }
3888 
3889 /*
3890  * Function:
3891  *	vdc_verify_seq_num()
3892  *
3893  * Description:
3894  *	This functions verifies that the sequence number sent back by the vDisk
3895  *	server with the latest message is what is expected (i.e. it is greater
3896  *	than the last seq num sent by the vDisk server and less than or equal
3897  *	to the last seq num generated by vdc).
3898  *
3899  *	It then checks the request ID to see if any requests need processing
3900  *	in the DRing.
3901  *
3902  * Arguments:
3903  *	vdc		- soft state pointer for this instance of the driver.
3904  *	dring_msg	- pointer to the LDC message sent by vds
3905  *
3906  * Return Code:
3907  *	VDC_SEQ_NUM_TODO	- Message needs to be processed
3908  *	VDC_SEQ_NUM_SKIP	- Message has already been processed
3909  *	VDC_SEQ_NUM_INVALID	- The seq numbers are so out of sync,
3910  *				  vdc cannot deal with them
3911  */
3912 static int
3913 vdc_verify_seq_num(vdc_t *vdc, vio_dring_msg_t *dring_msg)
3914 {
3915 	ASSERT(vdc != NULL);
3916 	ASSERT(dring_msg != NULL);
3917 	ASSERT(mutex_owned(&vdc->lock));
3918 
3919 	/*
3920 	 * Check to see if the messages were responded to in the correct
3921 	 * order by vds.
3922 	 */
3923 	if ((dring_msg->seq_num <= vdc->seq_num_reply) ||
3924 	    (dring_msg->seq_num > vdc->seq_num)) {
3925 		DMSG(vdc, 0, "?[%d] Bogus sequence_number %lu: "
3926 			"%lu > expected <= %lu (last proc req %lu sent %lu)\n",
3927 				vdc->instance, dring_msg->seq_num,
3928 				vdc->seq_num_reply, vdc->seq_num,
3929 				vdc->req_id_proc, vdc->req_id);
3930 		return (VDC_SEQ_NUM_INVALID);
3931 	}
3932 	vdc->seq_num_reply = dring_msg->seq_num;
3933 
3934 	if (vdc->req_id_proc < vdc->req_id)
3935 		return (VDC_SEQ_NUM_TODO);
3936 	else
3937 		return (VDC_SEQ_NUM_SKIP);
3938 }
3939 
3940 
3941 /*
3942  * Function:
3943  *	vdc_is_supported_version()
3944  *
3945  * Description:
3946  *	This routine checks if the major/minor version numbers specified in
3947  *	'ver_msg' are supported. If not it finds the next version that is
3948  *	in the supported version list 'vdc_version[]' and sets the fields in
3949  *	'ver_msg' to those values
3950  *
3951  * Arguments:
3952  *	ver_msg	- LDC message sent by vDisk server
3953  *
3954  * Return Code:
3955  *	B_TRUE	- Success
3956  *	B_FALSE	- Version not supported
3957  */
3958 static boolean_t
3959 vdc_is_supported_version(vio_ver_msg_t *ver_msg)
3960 {
3961 	int vdc_num_versions = sizeof (vdc_version) / sizeof (vdc_version[0]);
3962 
3963 	for (int i = 0; i < vdc_num_versions; i++) {
3964 		ASSERT(vdc_version[i].major > 0);
3965 		ASSERT((i == 0) ||
3966 		    (vdc_version[i].major < vdc_version[i-1].major));
3967 
3968 		/*
3969 		 * If the major versions match, adjust the minor version, if
3970 		 * necessary, down to the highest value supported by this
3971 		 * client. The server should support all minor versions lower
3972 		 * than the value it sent
3973 		 */
3974 		if (ver_msg->ver_major == vdc_version[i].major) {
3975 			if (ver_msg->ver_minor > vdc_version[i].minor) {
3976 				DMSGX(0,
3977 				    "Adjusting minor version from %u to %u",
3978 				    ver_msg->ver_minor, vdc_version[i].minor);
3979 				ver_msg->ver_minor = vdc_version[i].minor;
3980 			}
3981 			return (B_TRUE);
3982 		}
3983 
3984 		/*
3985 		 * If the message contains a higher major version number, set
3986 		 * the message's major/minor versions to the current values
3987 		 * and return false, so this message will get resent with
3988 		 * these values, and the server will potentially try again
3989 		 * with the same or a lower version
3990 		 */
3991 		if (ver_msg->ver_major > vdc_version[i].major) {
3992 			ver_msg->ver_major = vdc_version[i].major;
3993 			ver_msg->ver_minor = vdc_version[i].minor;
3994 			DMSGX(0, "Suggesting major/minor (0x%x/0x%x)\n",
3995 				ver_msg->ver_major, ver_msg->ver_minor);
3996 
3997 			return (B_FALSE);
3998 		}
3999 
4000 		/*
4001 		 * Otherwise, the message's major version is less than the
4002 		 * current major version, so continue the loop to the next
4003 		 * (lower) supported version
4004 		 */
4005 	}
4006 
4007 	/*
4008 	 * No common version was found; "ground" the version pair in the
4009 	 * message to terminate negotiation
4010 	 */
4011 	ver_msg->ver_major = 0;
4012 	ver_msg->ver_minor = 0;
4013 
4014 	return (B_FALSE);
4015 }
4016 /* -------------------------------------------------------------------------- */
4017 
4018 /*
4019  * DKIO(7) support
4020  */
4021 
4022 typedef struct vdc_dk_arg {
4023 	struct dk_callback	dkc;
4024 	int			mode;
4025 	dev_t			dev;
4026 	vdc_t			*vdc;
4027 } vdc_dk_arg_t;
4028 
4029 /*
4030  * Function:
4031  * 	vdc_dkio_flush_cb()
4032  *
4033  * Description:
4034  *	This routine is a callback for DKIOCFLUSHWRITECACHE which can be called
4035  *	by kernel code.
4036  *
4037  * Arguments:
4038  *	arg	- a pointer to a vdc_dk_arg_t structure.
4039  */
4040 void
4041 vdc_dkio_flush_cb(void *arg)
4042 {
4043 	struct vdc_dk_arg	*dk_arg = (struct vdc_dk_arg *)arg;
4044 	struct dk_callback	*dkc = NULL;
4045 	vdc_t			*vdc = NULL;
4046 	int			rv;
4047 
4048 	if (dk_arg == NULL) {
4049 		cmn_err(CE_NOTE, "?[Unk] DKIOCFLUSHWRITECACHE arg is NULL\n");
4050 		return;
4051 	}
4052 	dkc = &dk_arg->dkc;
4053 	vdc = dk_arg->vdc;
4054 	ASSERT(vdc != NULL);
4055 
4056 	rv = vdc_do_sync_op(vdc, VD_OP_FLUSH, NULL, 0,
4057 	    VDCPART(dk_arg->dev), 0, CB_SYNC, 0, VIO_both_dir);
4058 	if (rv != 0) {
4059 		DMSG(vdc, 0, "[%d] DKIOCFLUSHWRITECACHE failed %d : model %x\n",
4060 			vdc->instance, rv,
4061 			ddi_model_convert_from(dk_arg->mode & FMODELS));
4062 	}
4063 
4064 	/*
4065 	 * Trigger the call back to notify the caller the the ioctl call has
4066 	 * been completed.
4067 	 */
4068 	if ((dk_arg->mode & FKIOCTL) &&
4069 	    (dkc != NULL) &&
4070 	    (dkc->dkc_callback != NULL)) {
4071 		ASSERT(dkc->dkc_cookie != NULL);
4072 		(*dkc->dkc_callback)(dkc->dkc_cookie, rv);
4073 	}
4074 
4075 	/* Indicate that one less DKIO write flush is outstanding */
4076 	mutex_enter(&vdc->lock);
4077 	vdc->dkio_flush_pending--;
4078 	ASSERT(vdc->dkio_flush_pending >= 0);
4079 	mutex_exit(&vdc->lock);
4080 
4081 	/* free the mem that was allocated when the callback was dispatched */
4082 	kmem_free(arg, sizeof (vdc_dk_arg_t));
4083 }
4084 
4085 /*
4086  * This structure is used in the DKIO(7I) array below.
4087  */
4088 typedef struct vdc_dk_ioctl {
4089 	uint8_t		op;		/* VD_OP_XXX value */
4090 	int		cmd;		/* Solaris ioctl operation number */
4091 	size_t		nbytes;		/* size of structure to be copied */
4092 
4093 	/* function to convert between vDisk and Solaris structure formats */
4094 	int	(*convert)(vdc_t *vdc, void *vd_buf, void *ioctl_arg,
4095 	    int mode, int dir);
4096 } vdc_dk_ioctl_t;
4097 
4098 /*
4099  * Subset of DKIO(7I) operations currently supported
4100  */
4101 static vdc_dk_ioctl_t	dk_ioctl[] = {
4102 	{VD_OP_FLUSH,		DKIOCFLUSHWRITECACHE,	0,
4103 		vdc_null_copy_func},
4104 	{VD_OP_GET_WCE,		DKIOCGETWCE,		sizeof (int),
4105 		vdc_get_wce_convert},
4106 	{VD_OP_SET_WCE,		DKIOCSETWCE,		sizeof (int),
4107 		vdc_set_wce_convert},
4108 	{VD_OP_GET_VTOC,	DKIOCGVTOC,		sizeof (vd_vtoc_t),
4109 		vdc_get_vtoc_convert},
4110 	{VD_OP_SET_VTOC,	DKIOCSVTOC,		sizeof (vd_vtoc_t),
4111 		vdc_set_vtoc_convert},
4112 	{VD_OP_GET_DISKGEOM,	DKIOCGGEOM,		sizeof (vd_geom_t),
4113 		vdc_get_geom_convert},
4114 	{VD_OP_GET_DISKGEOM,	DKIOCG_PHYGEOM,		sizeof (vd_geom_t),
4115 		vdc_get_geom_convert},
4116 	{VD_OP_GET_DISKGEOM, 	DKIOCG_VIRTGEOM,	sizeof (vd_geom_t),
4117 		vdc_get_geom_convert},
4118 	{VD_OP_SET_DISKGEOM,	DKIOCSGEOM,		sizeof (vd_geom_t),
4119 		vdc_set_geom_convert},
4120 	{VD_OP_GET_EFI,		DKIOCGETEFI,		0,
4121 		vdc_get_efi_convert},
4122 	{VD_OP_SET_EFI,		DKIOCSETEFI,		0,
4123 		vdc_set_efi_convert},
4124 
4125 	/*
4126 	 * These particular ioctls are not sent to the server - vdc fakes up
4127 	 * the necessary info.
4128 	 */
4129 	{0, DKIOCINFO, sizeof (struct dk_cinfo), vdc_null_copy_func},
4130 	{0, DKIOCGMEDIAINFO, sizeof (struct dk_minfo), vdc_null_copy_func},
4131 	{0, USCSICMD,	sizeof (struct uscsi_cmd), vdc_null_copy_func},
4132 	{0, DKIOCREMOVABLE, 0, vdc_null_copy_func},
4133 	{0, CDROMREADOFFSET, 0, vdc_null_copy_func}
4134 };
4135 
4136 /*
4137  * Function:
4138  *	vd_process_ioctl()
4139  *
4140  * Description:
4141  *	This routine processes disk specific ioctl calls
4142  *
4143  * Arguments:
4144  *	dev	- the device number
4145  *	cmd	- the operation [dkio(7I)] to be processed
4146  *	arg	- pointer to user provided structure
4147  *		  (contains data to be set or reference parameter for get)
4148  *	mode	- bit flag, indicating open settings, 32/64 bit type, etc
4149  *
4150  * Return Code:
4151  *	0
4152  *	EFAULT
4153  *	ENXIO
4154  *	EIO
4155  *	ENOTSUP
4156  */
4157 static int
4158 vd_process_ioctl(dev_t dev, int cmd, caddr_t arg, int mode)
4159 {
4160 	int		instance = VDCUNIT(dev);
4161 	vdc_t		*vdc = NULL;
4162 	int		rv = -1;
4163 	int		idx = 0;		/* index into dk_ioctl[] */
4164 	size_t		len = 0;		/* #bytes to send to vds */
4165 	size_t		alloc_len = 0;		/* #bytes to allocate mem for */
4166 	caddr_t		mem_p = NULL;
4167 	size_t		nioctls = (sizeof (dk_ioctl)) / (sizeof (dk_ioctl[0]));
4168 	struct vtoc	vtoc_saved;
4169 	vdc_dk_ioctl_t	*iop;
4170 
4171 	vdc = ddi_get_soft_state(vdc_state, instance);
4172 	if (vdc == NULL) {
4173 		cmn_err(CE_NOTE, "![%d] Could not get soft state structure",
4174 		    instance);
4175 		return (ENXIO);
4176 	}
4177 
4178 	DMSG(vdc, 0, "[%d] Processing ioctl(%x) for dev %lx : model %x\n",
4179 		instance, cmd, dev, ddi_model_convert_from(mode & FMODELS));
4180 
4181 	/*
4182 	 * Validate the ioctl operation to be performed.
4183 	 *
4184 	 * If we have looped through the array without finding a match then we
4185 	 * don't support this ioctl.
4186 	 */
4187 	for (idx = 0; idx < nioctls; idx++) {
4188 		if (cmd == dk_ioctl[idx].cmd)
4189 			break;
4190 	}
4191 
4192 	if (idx >= nioctls) {
4193 		DMSG(vdc, 0, "[%d] Unsupported ioctl (0x%x)\n",
4194 		    vdc->instance, cmd);
4195 		return (ENOTSUP);
4196 	}
4197 
4198 	iop = &(dk_ioctl[idx]);
4199 
4200 	if (cmd == DKIOCGETEFI || cmd == DKIOCSETEFI) {
4201 		/* size is not fixed for EFI ioctls, it depends on ioctl arg */
4202 		dk_efi_t	dk_efi;
4203 
4204 		rv = ddi_copyin(arg, &dk_efi, sizeof (dk_efi_t), mode);
4205 		if (rv != 0)
4206 			return (EFAULT);
4207 
4208 		len = sizeof (vd_efi_t) - 1 + dk_efi.dki_length;
4209 	} else {
4210 		len = iop->nbytes;
4211 	}
4212 
4213 	/*
4214 	 * Deal with the ioctls which the server does not provide. vdc can
4215 	 * fake these up and return immediately
4216 	 */
4217 	switch (cmd) {
4218 	case CDROMREADOFFSET:
4219 	case DKIOCREMOVABLE:
4220 	case USCSICMD:
4221 		return (ENOTTY);
4222 
4223 	case DKIOCINFO:
4224 		{
4225 			struct dk_cinfo	cinfo;
4226 			if (vdc->cinfo == NULL)
4227 				return (ENXIO);
4228 
4229 			bcopy(vdc->cinfo, &cinfo, sizeof (struct dk_cinfo));
4230 			cinfo.dki_partition = VDCPART(dev);
4231 
4232 			rv = ddi_copyout(&cinfo, (void *)arg,
4233 					sizeof (struct dk_cinfo), mode);
4234 			if (rv != 0)
4235 				return (EFAULT);
4236 
4237 			return (0);
4238 		}
4239 
4240 	case DKIOCGMEDIAINFO:
4241 		{
4242 			if (vdc->minfo == NULL)
4243 				return (ENXIO);
4244 
4245 			rv = ddi_copyout(vdc->minfo, (void *)arg,
4246 					sizeof (struct dk_minfo), mode);
4247 			if (rv != 0)
4248 				return (EFAULT);
4249 
4250 			return (0);
4251 		}
4252 
4253 	case DKIOCFLUSHWRITECACHE:
4254 		{
4255 			struct dk_callback *dkc = (struct dk_callback *)arg;
4256 			vdc_dk_arg_t	*dkarg = NULL;
4257 
4258 			DMSG(vdc, 1, "[%d] Flush W$: mode %x\n",
4259 			    instance, mode);
4260 
4261 			/*
4262 			 * If the backing device is not a 'real' disk then the
4263 			 * W$ operation request to the vDisk server will fail
4264 			 * so we might as well save the cycles and return now.
4265 			 */
4266 			if (vdc->vdisk_type != VD_DISK_TYPE_DISK)
4267 				return (ENOTTY);
4268 
4269 			/*
4270 			 * If arg is NULL, then there is no callback function
4271 			 * registered and the call operates synchronously; we
4272 			 * break and continue with the rest of the function and
4273 			 * wait for vds to return (i.e. after the request to
4274 			 * vds returns successfully, all writes completed prior
4275 			 * to the ioctl will have been flushed from the disk
4276 			 * write cache to persistent media.
4277 			 *
4278 			 * If a callback function is registered, we dispatch
4279 			 * the request on a task queue and return immediately.
4280 			 * The callback will deal with informing the calling
4281 			 * thread that the flush request is completed.
4282 			 */
4283 			if (dkc == NULL)
4284 				break;
4285 
4286 			/*
4287 			 * the asynchronous callback is only supported if
4288 			 * invoked from within the kernel
4289 			 */
4290 			if ((mode & FKIOCTL) == 0)
4291 				return (ENOTSUP);
4292 
4293 			dkarg = kmem_zalloc(sizeof (vdc_dk_arg_t), KM_SLEEP);
4294 
4295 			dkarg->mode = mode;
4296 			dkarg->dev = dev;
4297 			bcopy(dkc, &dkarg->dkc, sizeof (*dkc));
4298 
4299 			mutex_enter(&vdc->lock);
4300 			vdc->dkio_flush_pending++;
4301 			dkarg->vdc = vdc;
4302 			mutex_exit(&vdc->lock);
4303 
4304 			/* put the request on a task queue */
4305 			rv = taskq_dispatch(system_taskq, vdc_dkio_flush_cb,
4306 				(void *)dkarg, DDI_SLEEP);
4307 			if (rv == NULL) {
4308 				/* clean up if dispatch fails */
4309 				mutex_enter(&vdc->lock);
4310 				vdc->dkio_flush_pending--;
4311 				kmem_free(dkarg, sizeof (vdc_dk_arg_t));
4312 			}
4313 
4314 			return (rv == NULL ? ENOMEM : 0);
4315 		}
4316 	}
4317 
4318 	/* catch programming error in vdc - should be a VD_OP_XXX ioctl */
4319 	ASSERT(iop->op != 0);
4320 
4321 	/* LDC requires that the memory being mapped is 8-byte aligned */
4322 	alloc_len = P2ROUNDUP(len, sizeof (uint64_t));
4323 	DMSG(vdc, 1, "[%d] struct size %ld alloc %ld\n",
4324 	    instance, len, alloc_len);
4325 
4326 	ASSERT(alloc_len >= 0); /* sanity check */
4327 	if (alloc_len > 0)
4328 		mem_p = kmem_zalloc(alloc_len, KM_SLEEP);
4329 
4330 	if (cmd == DKIOCSVTOC) {
4331 		/*
4332 		 * Save a copy of the current VTOC so that we can roll back
4333 		 * if the setting of the new VTOC fails.
4334 		 */
4335 		bcopy(vdc->vtoc, &vtoc_saved, sizeof (struct vtoc));
4336 	}
4337 
4338 	/*
4339 	 * Call the conversion function for this ioctl which, if necessary,
4340 	 * converts from the Solaris format to the format ARC'ed
4341 	 * as part of the vDisk protocol (FWARC 2006/195)
4342 	 */
4343 	ASSERT(iop->convert != NULL);
4344 	rv = (iop->convert)(vdc, arg, mem_p, mode, VD_COPYIN);
4345 	if (rv != 0) {
4346 		DMSG(vdc, 0, "[%d] convert func returned %d for ioctl 0x%x\n",
4347 				instance, rv, cmd);
4348 		if (mem_p != NULL)
4349 			kmem_free(mem_p, alloc_len);
4350 		return (rv);
4351 	}
4352 
4353 	/*
4354 	 * send request to vds to service the ioctl.
4355 	 */
4356 	rv = vdc_do_sync_op(vdc, iop->op, mem_p, alloc_len,
4357 	    VDCPART(dev), 0, CB_SYNC, (void *)(uint64_t)mode,
4358 	    VIO_both_dir);
4359 
4360 	if (rv != 0) {
4361 		/*
4362 		 * This is not necessarily an error. The ioctl could
4363 		 * be returning a value such as ENOTTY to indicate
4364 		 * that the ioctl is not applicable.
4365 		 */
4366 		DMSG(vdc, 0, "[%d] vds returned %d for ioctl 0x%x\n",
4367 			instance, rv, cmd);
4368 		if (mem_p != NULL)
4369 			kmem_free(mem_p, alloc_len);
4370 
4371 		if (cmd == DKIOCSVTOC) {
4372 			/* update of the VTOC has failed, roll back */
4373 			bcopy(&vtoc_saved, vdc->vtoc, sizeof (struct vtoc));
4374 		}
4375 
4376 		return (rv);
4377 	}
4378 
4379 	if (cmd == DKIOCSVTOC) {
4380 		/*
4381 		 * The VTOC has been changed. We need to update the device
4382 		 * nodes to handle the case where an EFI label has been
4383 		 * changed to a VTOC label. We also try and update the device
4384 		 * node properties. Failing to set the properties should
4385 		 * not cause an error to be return the caller though.
4386 		 */
4387 		vdc->vdisk_label = VD_DISK_LABEL_VTOC;
4388 		(void) vdc_create_device_nodes_vtoc(vdc);
4389 
4390 		if (vdc_create_device_nodes_props(vdc)) {
4391 			DMSG(vdc, 0, "![%d] Failed to update device nodes"
4392 			    " properties", vdc->instance);
4393 		}
4394 
4395 	} else if (cmd == DKIOCSETEFI) {
4396 		/*
4397 		 * The EFI has been changed. We need to update the device
4398 		 * nodes to handle the case where a VTOC label has been
4399 		 * changed to an EFI label. We also try and update the device
4400 		 * node properties. Failing to set the properties should
4401 		 * not cause an error to be return the caller though.
4402 		 */
4403 		struct dk_gpt *efi;
4404 		size_t efi_len;
4405 
4406 		vdc->vdisk_label = VD_DISK_LABEL_EFI;
4407 		(void) vdc_create_device_nodes_efi(vdc);
4408 
4409 		rv = vdc_efi_alloc_and_read(dev, &efi, &efi_len);
4410 
4411 		if (rv == 0) {
4412 			vdc_store_efi(vdc, efi);
4413 			rv = vdc_create_device_nodes_props(vdc);
4414 			vd_efi_free(efi, efi_len);
4415 		}
4416 
4417 		if (rv) {
4418 			DMSG(vdc, 0, "![%d] Failed to update device nodes"
4419 			    " properties", vdc->instance);
4420 		}
4421 	}
4422 
4423 	/*
4424 	 * Call the conversion function (if it exists) for this ioctl
4425 	 * which converts from the format ARC'ed as part of the vDisk
4426 	 * protocol (FWARC 2006/195) back to a format understood by
4427 	 * the rest of Solaris.
4428 	 */
4429 	rv = (iop->convert)(vdc, mem_p, arg, mode, VD_COPYOUT);
4430 	if (rv != 0) {
4431 		DMSG(vdc, 0, "[%d] convert func returned %d for ioctl 0x%x\n",
4432 				instance, rv, cmd);
4433 		if (mem_p != NULL)
4434 			kmem_free(mem_p, alloc_len);
4435 		return (rv);
4436 	}
4437 
4438 	if (mem_p != NULL)
4439 		kmem_free(mem_p, alloc_len);
4440 
4441 	return (rv);
4442 }
4443 
4444 /*
4445  * Function:
4446  *
4447  * Description:
4448  *	This is an empty conversion function used by ioctl calls which
4449  *	do not need to convert the data being passed in/out to userland
4450  */
4451 static int
4452 vdc_null_copy_func(vdc_t *vdc, void *from, void *to, int mode, int dir)
4453 {
4454 	_NOTE(ARGUNUSED(vdc))
4455 	_NOTE(ARGUNUSED(from))
4456 	_NOTE(ARGUNUSED(to))
4457 	_NOTE(ARGUNUSED(mode))
4458 	_NOTE(ARGUNUSED(dir))
4459 
4460 	return (0);
4461 }
4462 
4463 static int
4464 vdc_get_wce_convert(vdc_t *vdc, void *from, void *to,
4465     int mode, int dir)
4466 {
4467 	_NOTE(ARGUNUSED(vdc))
4468 
4469 	if (dir == VD_COPYIN)
4470 		return (0);		/* nothing to do */
4471 
4472 	if (ddi_copyout(from, to, sizeof (int), mode) != 0)
4473 		return (EFAULT);
4474 
4475 	return (0);
4476 }
4477 
4478 static int
4479 vdc_set_wce_convert(vdc_t *vdc, void *from, void *to,
4480     int mode, int dir)
4481 {
4482 	_NOTE(ARGUNUSED(vdc))
4483 
4484 	if (dir == VD_COPYOUT)
4485 		return (0);		/* nothing to do */
4486 
4487 	if (ddi_copyin(from, to, sizeof (int), mode) != 0)
4488 		return (EFAULT);
4489 
4490 	return (0);
4491 }
4492 
4493 /*
4494  * Function:
4495  *	vdc_get_vtoc_convert()
4496  *
4497  * Description:
4498  *	This routine performs the necessary convertions from the DKIOCGVTOC
4499  *	Solaris structure to the format defined in FWARC 2006/195.
4500  *
4501  *	In the struct vtoc definition, the timestamp field is marked as not
4502  *	supported so it is not part of vDisk protocol (FWARC 2006/195).
4503  *	However SVM uses that field to check it can write into the VTOC,
4504  *	so we fake up the info of that field.
4505  *
4506  * Arguments:
4507  *	vdc	- the vDisk client
4508  *	from	- the buffer containing the data to be copied from
4509  *	to	- the buffer to be copied to
4510  *	mode	- flags passed to ioctl() call
4511  *	dir	- the "direction" of the copy - VD_COPYIN or VD_COPYOUT
4512  *
4513  * Return Code:
4514  *	0	- Success
4515  *	ENXIO	- incorrect buffer passed in.
4516  *	EFAULT	- ddi_copyout routine encountered an error.
4517  */
4518 static int
4519 vdc_get_vtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
4520 {
4521 	int		i;
4522 	void		*tmp_mem = NULL;
4523 	void		*tmp_memp;
4524 	struct vtoc	vt;
4525 	struct vtoc32	vt32;
4526 	int		copy_len = 0;
4527 	int		rv = 0;
4528 
4529 	if (dir != VD_COPYOUT)
4530 		return (0);	/* nothing to do */
4531 
4532 	if ((from == NULL) || (to == NULL))
4533 		return (ENXIO);
4534 
4535 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32)
4536 		copy_len = sizeof (struct vtoc32);
4537 	else
4538 		copy_len = sizeof (struct vtoc);
4539 
4540 	tmp_mem = kmem_alloc(copy_len, KM_SLEEP);
4541 
4542 	VD_VTOC2VTOC((vd_vtoc_t *)from, &vt);
4543 
4544 	/* fake the VTOC timestamp field */
4545 	for (i = 0; i < V_NUMPAR; i++) {
4546 		vt.timestamp[i] = vdc->vtoc->timestamp[i];
4547 	}
4548 
4549 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
4550 		vtoctovtoc32(vt, vt32);
4551 		tmp_memp = &vt32;
4552 	} else {
4553 		tmp_memp = &vt;
4554 	}
4555 	rv = ddi_copyout(tmp_memp, to, copy_len, mode);
4556 	if (rv != 0)
4557 		rv = EFAULT;
4558 
4559 	kmem_free(tmp_mem, copy_len);
4560 	return (rv);
4561 }
4562 
4563 /*
4564  * Function:
4565  *	vdc_set_vtoc_convert()
4566  *
4567  * Description:
4568  *	This routine performs the necessary convertions from the DKIOCSVTOC
4569  *	Solaris structure to the format defined in FWARC 2006/195.
4570  *
4571  * Arguments:
4572  *	vdc	- the vDisk client
4573  *	from	- Buffer with data
4574  *	to	- Buffer where data is to be copied to
4575  *	mode	- flags passed to ioctl
4576  *	dir	- direction of copy (in or out)
4577  *
4578  * Return Code:
4579  *	0	- Success
4580  *	ENXIO	- Invalid buffer passed in
4581  *	EFAULT	- ddi_copyin of data failed
4582  */
4583 static int
4584 vdc_set_vtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
4585 {
4586 	void		*tmp_mem = NULL;
4587 	struct vtoc	vt;
4588 	struct vtoc	*vtp = &vt;
4589 	vd_vtoc_t	vtvd;
4590 	int		copy_len = 0;
4591 	int		rv = 0;
4592 
4593 	if (dir != VD_COPYIN)
4594 		return (0);	/* nothing to do */
4595 
4596 	if ((from == NULL) || (to == NULL))
4597 		return (ENXIO);
4598 
4599 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32)
4600 		copy_len = sizeof (struct vtoc32);
4601 	else
4602 		copy_len = sizeof (struct vtoc);
4603 
4604 	tmp_mem = kmem_alloc(copy_len, KM_SLEEP);
4605 
4606 	rv = ddi_copyin(from, tmp_mem, copy_len, mode);
4607 	if (rv != 0) {
4608 		kmem_free(tmp_mem, copy_len);
4609 		return (EFAULT);
4610 	}
4611 
4612 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
4613 		vtoc32tovtoc((*(struct vtoc32 *)tmp_mem), vt);
4614 	} else {
4615 		vtp = tmp_mem;
4616 	}
4617 
4618 	/*
4619 	 * The VTOC is being changed, then vdc needs to update the copy
4620 	 * it saved in the soft state structure.
4621 	 */
4622 	bcopy(vtp, vdc->vtoc, sizeof (struct vtoc));
4623 
4624 	VTOC2VD_VTOC(vtp, &vtvd);
4625 	bcopy(&vtvd, to, sizeof (vd_vtoc_t));
4626 	kmem_free(tmp_mem, copy_len);
4627 
4628 	return (0);
4629 }
4630 
4631 /*
4632  * Function:
4633  *	vdc_get_geom_convert()
4634  *
4635  * Description:
4636  *	This routine performs the necessary convertions from the DKIOCGGEOM,
4637  *	DKIOCG_PHYSGEOM and DKIOG_VIRTGEOM Solaris structures to the format
4638  *	defined in FWARC 2006/195
4639  *
4640  * Arguments:
4641  *	vdc	- the vDisk client
4642  *	from	- Buffer with data
4643  *	to	- Buffer where data is to be copied to
4644  *	mode	- flags passed to ioctl
4645  *	dir	- direction of copy (in or out)
4646  *
4647  * Return Code:
4648  *	0	- Success
4649  *	ENXIO	- Invalid buffer passed in
4650  *	EFAULT	- ddi_copyout of data failed
4651  */
4652 static int
4653 vdc_get_geom_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
4654 {
4655 	_NOTE(ARGUNUSED(vdc))
4656 
4657 	struct dk_geom	geom;
4658 	int	copy_len = sizeof (struct dk_geom);
4659 	int	rv = 0;
4660 
4661 	if (dir != VD_COPYOUT)
4662 		return (0);	/* nothing to do */
4663 
4664 	if ((from == NULL) || (to == NULL))
4665 		return (ENXIO);
4666 
4667 	VD_GEOM2DK_GEOM((vd_geom_t *)from, &geom);
4668 	rv = ddi_copyout(&geom, to, copy_len, mode);
4669 	if (rv != 0)
4670 		rv = EFAULT;
4671 
4672 	return (rv);
4673 }
4674 
4675 /*
4676  * Function:
4677  *	vdc_set_geom_convert()
4678  *
4679  * Description:
4680  *	This routine performs the necessary convertions from the DKIOCSGEOM
4681  *	Solaris structure to the format defined in FWARC 2006/195.
4682  *
4683  * Arguments:
4684  *	vdc	- the vDisk client
4685  *	from	- Buffer with data
4686  *	to	- Buffer where data is to be copied to
4687  *	mode	- flags passed to ioctl
4688  *	dir	- direction of copy (in or out)
4689  *
4690  * Return Code:
4691  *	0	- Success
4692  *	ENXIO	- Invalid buffer passed in
4693  *	EFAULT	- ddi_copyin of data failed
4694  */
4695 static int
4696 vdc_set_geom_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
4697 {
4698 	_NOTE(ARGUNUSED(vdc))
4699 
4700 	vd_geom_t	vdgeom;
4701 	void		*tmp_mem = NULL;
4702 	int		copy_len = sizeof (struct dk_geom);
4703 	int		rv = 0;
4704 
4705 	if (dir != VD_COPYIN)
4706 		return (0);	/* nothing to do */
4707 
4708 	if ((from == NULL) || (to == NULL))
4709 		return (ENXIO);
4710 
4711 	tmp_mem = kmem_alloc(copy_len, KM_SLEEP);
4712 
4713 	rv = ddi_copyin(from, tmp_mem, copy_len, mode);
4714 	if (rv != 0) {
4715 		kmem_free(tmp_mem, copy_len);
4716 		return (EFAULT);
4717 	}
4718 	DK_GEOM2VD_GEOM((struct dk_geom *)tmp_mem, &vdgeom);
4719 	bcopy(&vdgeom, to, sizeof (vdgeom));
4720 	kmem_free(tmp_mem, copy_len);
4721 
4722 	return (0);
4723 }
4724 
4725 static int
4726 vdc_get_efi_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
4727 {
4728 	_NOTE(ARGUNUSED(vdc))
4729 
4730 	vd_efi_t	*vd_efi;
4731 	dk_efi_t	dk_efi;
4732 	int		rv = 0;
4733 	void		*uaddr;
4734 
4735 	if ((from == NULL) || (to == NULL))
4736 		return (ENXIO);
4737 
4738 	if (dir == VD_COPYIN) {
4739 
4740 		vd_efi = (vd_efi_t *)to;
4741 
4742 		rv = ddi_copyin(from, &dk_efi, sizeof (dk_efi_t), mode);
4743 		if (rv != 0)
4744 			return (EFAULT);
4745 
4746 		vd_efi->lba = dk_efi.dki_lba;
4747 		vd_efi->length = dk_efi.dki_length;
4748 		bzero(vd_efi->data, vd_efi->length);
4749 
4750 	} else {
4751 
4752 		rv = ddi_copyin(to, &dk_efi, sizeof (dk_efi_t), mode);
4753 		if (rv != 0)
4754 			return (EFAULT);
4755 
4756 		uaddr = dk_efi.dki_data;
4757 
4758 		dk_efi.dki_data = kmem_alloc(dk_efi.dki_length, KM_SLEEP);
4759 
4760 		VD_EFI2DK_EFI((vd_efi_t *)from, &dk_efi);
4761 
4762 		rv = ddi_copyout(dk_efi.dki_data, uaddr, dk_efi.dki_length,
4763 		    mode);
4764 		if (rv != 0)
4765 			return (EFAULT);
4766 
4767 		kmem_free(dk_efi.dki_data, dk_efi.dki_length);
4768 	}
4769 
4770 	return (0);
4771 }
4772 
4773 static int
4774 vdc_set_efi_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
4775 {
4776 	_NOTE(ARGUNUSED(vdc))
4777 
4778 	dk_efi_t	dk_efi;
4779 	void		*uaddr;
4780 
4781 	if (dir == VD_COPYOUT)
4782 		return (0);	/* nothing to do */
4783 
4784 	if ((from == NULL) || (to == NULL))
4785 		return (ENXIO);
4786 
4787 	if (ddi_copyin(from, &dk_efi, sizeof (dk_efi_t), mode) != 0)
4788 		return (EFAULT);
4789 
4790 	uaddr = dk_efi.dki_data;
4791 
4792 	dk_efi.dki_data = kmem_alloc(dk_efi.dki_length, KM_SLEEP);
4793 
4794 	if (ddi_copyin(uaddr, dk_efi.dki_data, dk_efi.dki_length, mode) != 0)
4795 		return (EFAULT);
4796 
4797 	DK_EFI2VD_EFI(&dk_efi, (vd_efi_t *)to);
4798 
4799 	kmem_free(dk_efi.dki_data, dk_efi.dki_length);
4800 
4801 	return (0);
4802 }
4803 
4804 /*
4805  * Function:
4806  *	vdc_create_fake_geometry()
4807  *
4808  * Description:
4809  *	This routine fakes up the disk info needed for some DKIO ioctls.
4810  *		- DKIOCINFO
4811  *		- DKIOCGMEDIAINFO
4812  *
4813  *	[ just like lofi(7D) and ramdisk(7D) ]
4814  *
4815  * Arguments:
4816  *	vdc	- soft state pointer for this instance of the device driver.
4817  *
4818  * Return Code:
4819  *	0	- Success
4820  */
4821 static int
4822 vdc_create_fake_geometry(vdc_t *vdc)
4823 {
4824 	ASSERT(vdc != NULL);
4825 
4826 	/*
4827 	 * Check if max_xfer_sz and vdisk_size are valid
4828 	 */
4829 	if (vdc->vdisk_size == 0 || vdc->max_xfer_sz == 0)
4830 		return (EIO);
4831 
4832 	/*
4833 	 * DKIOCINFO support
4834 	 */
4835 	vdc->cinfo = kmem_zalloc(sizeof (struct dk_cinfo), KM_SLEEP);
4836 
4837 	(void) strcpy(vdc->cinfo->dki_cname, VDC_DRIVER_NAME);
4838 	(void) strcpy(vdc->cinfo->dki_dname, VDC_DRIVER_NAME);
4839 	/* max_xfer_sz is #blocks so we don't need to divide by DEV_BSIZE */
4840 	vdc->cinfo->dki_maxtransfer = vdc->max_xfer_sz;
4841 	vdc->cinfo->dki_ctype = DKC_SCSI_CCS;
4842 	vdc->cinfo->dki_flags = DKI_FMTVOL;
4843 	vdc->cinfo->dki_cnum = 0;
4844 	vdc->cinfo->dki_addr = 0;
4845 	vdc->cinfo->dki_space = 0;
4846 	vdc->cinfo->dki_prio = 0;
4847 	vdc->cinfo->dki_vec = 0;
4848 	vdc->cinfo->dki_unit = vdc->instance;
4849 	vdc->cinfo->dki_slave = 0;
4850 	/*
4851 	 * The partition number will be created on the fly depending on the
4852 	 * actual slice (i.e. minor node) that is used to request the data.
4853 	 */
4854 	vdc->cinfo->dki_partition = 0;
4855 
4856 	/*
4857 	 * DKIOCGMEDIAINFO support
4858 	 */
4859 	if (vdc->minfo == NULL)
4860 		vdc->minfo = kmem_zalloc(sizeof (struct dk_minfo), KM_SLEEP);
4861 	vdc->minfo->dki_media_type = DK_FIXED_DISK;
4862 	vdc->minfo->dki_capacity = vdc->vdisk_size;
4863 	vdc->minfo->dki_lbsize = DEV_BSIZE;
4864 
4865 	return (0);
4866 }
4867 
4868 /*
4869  * Function:
4870  *	vdc_setup_disk_layout()
4871  *
4872  * Description:
4873  *	This routine discovers all the necessary details about the "disk"
4874  *	by requesting the data that is available from the vDisk server and by
4875  *	faking up the rest of the data.
4876  *
4877  * Arguments:
4878  *	vdc	- soft state pointer for this instance of the device driver.
4879  *
4880  * Return Code:
4881  *	0	- Success
4882  */
4883 static int
4884 vdc_setup_disk_layout(vdc_t *vdc)
4885 {
4886 	buf_t	*buf;	/* BREAD requests need to be in a buf_t structure */
4887 	dev_t	dev;
4888 	int	slice = 0;
4889 	int	rv, error;
4890 
4891 	ASSERT(vdc != NULL);
4892 
4893 	if (vdc->vtoc == NULL)
4894 		vdc->vtoc = kmem_zalloc(sizeof (struct vtoc), KM_SLEEP);
4895 
4896 	dev = makedevice(ddi_driver_major(vdc->dip),
4897 				VD_MAKE_DEV(vdc->instance, 0));
4898 	rv = vd_process_ioctl(dev, DKIOCGVTOC, (caddr_t)vdc->vtoc, FKIOCTL);
4899 
4900 	if (rv && rv != ENOTSUP) {
4901 		DMSG(vdc, 0, "[%d] Failed to get VTOC (err=%d)",
4902 				vdc->instance, rv);
4903 		return (rv);
4904 	}
4905 
4906 	/*
4907 	 * The process of attempting to read VTOC will initiate
4908 	 * the handshake and establish a connection. Following
4909 	 * handshake, go ahead and create geometry.
4910 	 */
4911 	error = vdc_create_fake_geometry(vdc);
4912 	if (error != 0) {
4913 		DMSG(vdc, 0, "[%d] Failed to create disk geometry (err%d)",
4914 		    vdc->instance, error);
4915 		return (error);
4916 	}
4917 
4918 	if (rv == ENOTSUP) {
4919 		/*
4920 		 * If the device does not support VTOC then we try
4921 		 * to read an EFI label.
4922 		 */
4923 		struct dk_gpt *efi;
4924 		size_t efi_len;
4925 
4926 		rv = vdc_efi_alloc_and_read(dev, &efi, &efi_len);
4927 
4928 		if (rv) {
4929 			DMSG(vdc, 0, "[%d] Failed to get EFI (err=%d)",
4930 			    vdc->instance, rv);
4931 			return (rv);
4932 		}
4933 
4934 		vdc->vdisk_label = VD_DISK_LABEL_EFI;
4935 		vdc_store_efi(vdc, efi);
4936 		vd_efi_free(efi, efi_len);
4937 
4938 		return (0);
4939 	}
4940 
4941 	vdc->vdisk_label = VD_DISK_LABEL_VTOC;
4942 
4943 	/*
4944 	 * FUTURE: This could be default way for reading the VTOC
4945 	 * from the disk as supposed to sending the VD_OP_GET_VTOC
4946 	 * to the server. Currently this is a sanity check.
4947 	 *
4948 	 * find the slice that represents the entire "disk" and use that to
4949 	 * read the disk label. The convention in Solaris is that slice 2
4950 	 * represents the whole disk so we check that it is, otherwise we
4951 	 * default to slice 0
4952 	 */
4953 	if ((vdc->vdisk_type == VD_DISK_TYPE_DISK) &&
4954 	    (vdc->vtoc->v_part[2].p_tag == V_BACKUP)) {
4955 		slice = 2;
4956 	} else {
4957 		slice = 0;
4958 	}
4959 
4960 	/*
4961 	 * Read disk label from start of disk
4962 	 */
4963 	vdc->label = kmem_zalloc(DK_LABEL_SIZE, KM_SLEEP);
4964 	buf = kmem_alloc(sizeof (buf_t), KM_SLEEP);
4965 	bioinit(buf);
4966 	buf->b_un.b_addr = (caddr_t)vdc->label;
4967 	buf->b_bcount = DK_LABEL_SIZE;
4968 	buf->b_flags = B_BUSY | B_READ;
4969 	buf->b_dev = dev;
4970 	rv = vdc_send_request(vdc, VD_OP_BREAD, (caddr_t)vdc->label,
4971 	    DK_LABEL_SIZE, slice, 0, CB_STRATEGY, buf, VIO_read_dir);
4972 	if (rv) {
4973 		DMSG(vdc, 1, "[%d] Failed to read disk block 0\n",
4974 		    vdc->instance);
4975 		kmem_free(buf, sizeof (buf_t));
4976 		return (rv);
4977 	}
4978 	rv = biowait(buf);
4979 	biofini(buf);
4980 	kmem_free(buf, sizeof (buf_t));
4981 
4982 	return (rv);
4983 }
4984 
4985 /*
4986  * Function:
4987  *	vdc_setup_devid()
4988  *
4989  * Description:
4990  *	This routine discovers the devid of a vDisk. It requests the devid of
4991  *	the underlying device from the vDisk server, builds an encapsulated
4992  *	devid based on the retrieved devid and registers that new devid to
4993  *	the vDisk.
4994  *
4995  * Arguments:
4996  *	vdc	- soft state pointer for this instance of the device driver.
4997  *
4998  * Return Code:
4999  *	0	- A devid was succesfully registered for the vDisk
5000  */
5001 static int
5002 vdc_setup_devid(vdc_t *vdc)
5003 {
5004 	int rv;
5005 	vd_devid_t *vd_devid;
5006 	size_t bufsize, bufid_len;
5007 
5008 	/*
5009 	 * At first sight, we don't know the size of the devid that the
5010 	 * server will return but this size will be encoded into the
5011 	 * reply. So we do a first request using a default size then we
5012 	 * check if this size was large enough. If not then we do a second
5013 	 * request with the correct size returned by the server. Note that
5014 	 * ldc requires size to be 8-byte aligned.
5015 	 */
5016 	bufsize = P2ROUNDUP(VD_DEVID_SIZE(VD_DEVID_DEFAULT_LEN),
5017 	    sizeof (uint64_t));
5018 	vd_devid = kmem_zalloc(bufsize, KM_SLEEP);
5019 	bufid_len = bufsize - sizeof (vd_efi_t) - 1;
5020 
5021 	rv = vdc_do_sync_op(vdc, VD_OP_GET_DEVID, (caddr_t)vd_devid,
5022 	    bufsize, 0, 0, CB_SYNC, 0, VIO_both_dir);
5023 
5024 	DMSG(vdc, 2, "sync_op returned %d\n", rv);
5025 
5026 	if (rv) {
5027 		kmem_free(vd_devid, bufsize);
5028 		return (rv);
5029 	}
5030 
5031 	if (vd_devid->length > bufid_len) {
5032 		/*
5033 		 * The returned devid is larger than the buffer used. Try again
5034 		 * with a buffer with the right size.
5035 		 */
5036 		kmem_free(vd_devid, bufsize);
5037 		bufsize = P2ROUNDUP(VD_DEVID_SIZE(vd_devid->length),
5038 		    sizeof (uint64_t));
5039 		vd_devid = kmem_zalloc(bufsize, KM_SLEEP);
5040 		bufid_len = bufsize - sizeof (vd_efi_t) - 1;
5041 
5042 		rv = vdc_do_sync_op(vdc, VD_OP_GET_DEVID,
5043 		    (caddr_t)vd_devid, bufsize, 0, 0, CB_SYNC, 0,
5044 		    VIO_both_dir);
5045 
5046 		if (rv) {
5047 			kmem_free(vd_devid, bufsize);
5048 			return (rv);
5049 		}
5050 	}
5051 
5052 	/*
5053 	 * The virtual disk should have the same device id as the one associated
5054 	 * with the physical disk it is mapped on, otherwise sharing a disk
5055 	 * between a LDom and a non-LDom may not work (for example for a shared
5056 	 * SVM disk set).
5057 	 *
5058 	 * The DDI framework does not allow creating a device id with any
5059 	 * type so we first create a device id of type DEVID_ENCAP and then
5060 	 * we restore the orignal type of the physical device.
5061 	 */
5062 
5063 	DMSG(vdc, 2, ": devid length = %d\n", vd_devid->length);
5064 
5065 	/* build an encapsulated devid based on the returned devid */
5066 	if (ddi_devid_init(vdc->dip, DEVID_ENCAP, vd_devid->length,
5067 		vd_devid->id, &vdc->devid) != DDI_SUCCESS) {
5068 		DMSG(vdc, 1, "[%d] Fail to created devid\n", vdc->instance);
5069 		kmem_free(vd_devid, bufsize);
5070 		return (1);
5071 	}
5072 
5073 	DEVID_FORMTYPE((impl_devid_t *)vdc->devid, vd_devid->type);
5074 
5075 	ASSERT(ddi_devid_valid(vdc->devid) == DDI_SUCCESS);
5076 
5077 	kmem_free(vd_devid, bufsize);
5078 
5079 	if (ddi_devid_register(vdc->dip, vdc->devid) != DDI_SUCCESS) {
5080 		DMSG(vdc, 1, "[%d] Fail to register devid\n", vdc->instance);
5081 		return (1);
5082 	}
5083 
5084 	return (0);
5085 }
5086 
5087 static void
5088 vdc_store_efi(vdc_t *vdc, struct dk_gpt *efi)
5089 {
5090 	struct vtoc *vtoc = vdc->vtoc;
5091 
5092 	vd_efi_to_vtoc(efi, vtoc);
5093 	if (vdc->vdisk_type == VD_DISK_TYPE_SLICE) {
5094 		/*
5095 		 * vd_efi_to_vtoc() will store information about the EFI Sun
5096 		 * reserved partition (representing the entire disk) into
5097 		 * partition 7. However single-slice device will only have
5098 		 * that single partition and the vdc driver expects to find
5099 		 * information about that partition in slice 0. So we need
5100 		 * to copy information from slice 7 to slice 0.
5101 		 */
5102 		vtoc->v_part[0].p_tag = vtoc->v_part[VD_EFI_WD_SLICE].p_tag;
5103 		vtoc->v_part[0].p_flag = vtoc->v_part[VD_EFI_WD_SLICE].p_flag;
5104 		vtoc->v_part[0].p_start = vtoc->v_part[VD_EFI_WD_SLICE].p_start;
5105 		vtoc->v_part[0].p_size =  vtoc->v_part[VD_EFI_WD_SLICE].p_size;
5106 	}
5107 }
5108