xref: /titanic_41/usr/src/uts/sun4v/io/vdc.c (revision 2e1a94749a6ae1ee25de9f4492d4b90a3b408c4c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * LDoms virtual disk client (vdc) device driver
29  *
30  * This driver runs on a guest logical domain and communicates with the virtual
31  * disk server (vds) driver running on the service domain which is exporting
32  * virtualized "disks" to the guest logical domain.
33  *
34  * The driver can be divided into four sections:
35  *
36  * 1) generic device driver housekeeping
37  *	_init, _fini, attach, detach, ops structures, etc.
38  *
39  * 2) communication channel setup
40  *	Setup the communications link over the LDC channel that vdc uses to
41  *	talk to the vDisk server. Initialise the descriptor ring which
42  *	allows the LDC clients to transfer data via memory mappings.
43  *
44  * 3) Support exported to upper layers (filesystems, etc)
45  *	The upper layers call into vdc via strategy(9E) and DKIO(7I)
46  *	ioctl calls. vdc will copy the data to be written to the descriptor
47  *	ring or maps the buffer to store the data read by the vDisk
48  *	server into the descriptor ring. It then sends a message to the
49  *	vDisk server requesting it to complete the operation.
50  *
51  * 4) Handling responses from vDisk server.
52  *	The vDisk server will ACK some or all of the messages vdc sends to it
53  *	(this is configured during the handshake). Upon receipt of an ACK
54  *	vdc will check the descriptor ring and signal to the upper layer
55  *	code waiting on the IO.
56  */
57 
58 #include <sys/atomic.h>
59 #include <sys/conf.h>
60 #include <sys/disp.h>
61 #include <sys/ddi.h>
62 #include <sys/dkio.h>
63 #include <sys/efi_partition.h>
64 #include <sys/fcntl.h>
65 #include <sys/file.h>
66 #include <sys/kstat.h>
67 #include <sys/mach_descrip.h>
68 #include <sys/modctl.h>
69 #include <sys/mdeg.h>
70 #include <sys/note.h>
71 #include <sys/open.h>
72 #include <sys/sdt.h>
73 #include <sys/stat.h>
74 #include <sys/sunddi.h>
75 #include <sys/types.h>
76 #include <sys/promif.h>
77 #include <sys/var.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/dktp/dadkio.h>
85 #include <sys/mhd.h>
86 #include <sys/scsi/generic/sense.h>
87 #include <sys/scsi/impl/uscsi.h>
88 #include <sys/scsi/impl/services.h>
89 #include <sys/scsi/targets/sddef.h>
90 
91 #include <sys/ldoms.h>
92 #include <sys/ldc.h>
93 #include <sys/vio_common.h>
94 #include <sys/vio_mailbox.h>
95 #include <sys/vio_util.h>
96 #include <sys/vdsk_common.h>
97 #include <sys/vdsk_mailbox.h>
98 #include <sys/vdc.h>
99 
100 #define	VD_OLDVTOC_LIMIT	0x7fffffff
101 
102 /*
103  * function prototypes
104  */
105 
106 /* standard driver functions */
107 static int	vdc_open(dev_t *dev, int flag, int otyp, cred_t *cred);
108 static int	vdc_close(dev_t dev, int flag, int otyp, cred_t *cred);
109 static int	vdc_strategy(struct buf *buf);
110 static int	vdc_print(dev_t dev, char *str);
111 static int	vdc_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk);
112 static int	vdc_read(dev_t dev, struct uio *uio, cred_t *cred);
113 static int	vdc_write(dev_t dev, struct uio *uio, cred_t *cred);
114 static int	vdc_ioctl(dev_t dev, int cmd, intptr_t arg, int mode,
115 			cred_t *credp, int *rvalp);
116 static int	vdc_aread(dev_t dev, struct aio_req *aio, cred_t *cred);
117 static int	vdc_awrite(dev_t dev, struct aio_req *aio, cred_t *cred);
118 
119 static int	vdc_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd,
120 			void *arg, void **resultp);
121 static int	vdc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
122 static int	vdc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);
123 static int	vdc_prop_op(dev_t dev, dev_info_t *dip, ddi_prop_op_t prop_op,
124 		    int mod_flags, char *name, caddr_t valuep, int *lengthp);
125 
126 /* setup */
127 static void	vdc_min(struct buf *bufp);
128 static int	vdc_send(vdc_t *vdc, caddr_t pkt, size_t *msglen);
129 static int	vdc_do_ldc_init(vdc_t *vdc, vdc_server_t *srvr);
130 static int	vdc_start_ldc_connection(vdc_t *vdc);
131 static int	vdc_create_device_nodes(vdc_t *vdc);
132 static int	vdc_create_device_nodes_efi(vdc_t *vdc);
133 static int	vdc_create_device_nodes_vtoc(vdc_t *vdc);
134 static void	vdc_create_io_kstats(vdc_t *vdc);
135 static void	vdc_create_err_kstats(vdc_t *vdc);
136 static void	vdc_set_err_kstats(vdc_t *vdc);
137 static int	vdc_get_md_node(dev_info_t *dip, md_t **mdpp,
138 		    mde_cookie_t *vd_nodep);
139 static int	vdc_init_ports(vdc_t *vdc, md_t *mdp, mde_cookie_t vd_nodep);
140 static void	vdc_fini_ports(vdc_t *vdc);
141 static void	vdc_switch_server(vdc_t *vdcp);
142 static int	vdc_do_ldc_up(vdc_t *vdc);
143 static void	vdc_terminate_ldc(vdc_t *vdc, vdc_server_t *srvr);
144 static int	vdc_init_descriptor_ring(vdc_t *vdc);
145 static void	vdc_destroy_descriptor_ring(vdc_t *vdc);
146 static int	vdc_setup_devid(vdc_t *vdc);
147 static void	vdc_store_label_efi(vdc_t *, efi_gpt_t *, efi_gpe_t *);
148 static void	vdc_store_label_vtoc(vdc_t *, struct dk_geom *,
149 		    struct extvtoc *);
150 static void	vdc_store_label_unk(vdc_t *vdc);
151 static boolean_t vdc_is_opened(vdc_t *vdc);
152 static void	vdc_update_size(vdc_t *vdc, size_t, size_t, size_t);
153 
154 /* handshake with vds */
155 static int		vdc_init_ver_negotiation(vdc_t *vdc, vio_ver_t ver);
156 static int		vdc_ver_negotiation(vdc_t *vdcp);
157 static int		vdc_init_attr_negotiation(vdc_t *vdc);
158 static int		vdc_attr_negotiation(vdc_t *vdcp);
159 static int		vdc_init_dring_negotiate(vdc_t *vdc);
160 static int		vdc_dring_negotiation(vdc_t *vdcp);
161 static int		vdc_send_rdx(vdc_t *vdcp);
162 static int		vdc_rdx_exchange(vdc_t *vdcp);
163 static boolean_t	vdc_is_supported_version(vio_ver_msg_t *ver_msg);
164 
165 /* processing incoming messages from vDisk server */
166 static void	vdc_process_msg_thread(vdc_t *vdc);
167 static int	vdc_recv(vdc_t *vdc, vio_msg_t *msgp, size_t *nbytesp);
168 
169 static uint_t	vdc_handle_cb(uint64_t event, caddr_t arg);
170 static int	vdc_process_data_msg(vdc_t *vdc, vio_msg_t *msg);
171 static int	vdc_handle_ver_msg(vdc_t *vdc, vio_ver_msg_t *ver_msg);
172 static int	vdc_handle_attr_msg(vdc_t *vdc, vd_attr_msg_t *attr_msg);
173 static int	vdc_handle_dring_reg_msg(vdc_t *vdc, vio_dring_reg_msg_t *msg);
174 static int 	vdc_send_request(vdc_t *vdcp, int operation,
175 		    caddr_t addr, size_t nbytes, int slice, diskaddr_t offset,
176 		    int cb_type, void *cb_arg, vio_desc_direction_t dir);
177 static int	vdc_map_to_shared_dring(vdc_t *vdcp, int idx);
178 static int 	vdc_populate_descriptor(vdc_t *vdcp, int operation,
179 		    caddr_t addr, size_t nbytes, int slice, diskaddr_t offset,
180 		    int cb_type, void *cb_arg, vio_desc_direction_t dir);
181 static int 	vdc_do_sync_op(vdc_t *vdcp, int operation, caddr_t addr,
182 		    size_t nbytes, int slice, diskaddr_t offset, int cb_type,
183 		    void *cb_arg, vio_desc_direction_t dir, boolean_t);
184 
185 static int	vdc_wait_for_response(vdc_t *vdcp, vio_msg_t *msgp);
186 static int	vdc_drain_response(vdc_t *vdcp, struct buf *buf);
187 static int	vdc_depopulate_descriptor(vdc_t *vdc, uint_t idx);
188 static int	vdc_populate_mem_hdl(vdc_t *vdcp, vdc_local_desc_t *ldep);
189 static int	vdc_verify_seq_num(vdc_t *vdc, vio_dring_msg_t *dring_msg);
190 
191 /* dkio */
192 static int	vd_process_ioctl(dev_t dev, int cmd, caddr_t arg, int mode,
193 		    int *rvalp);
194 static int	vd_process_efi_ioctl(void *vdisk, int cmd, uintptr_t arg);
195 static void	vdc_create_fake_geometry(vdc_t *vdc);
196 static int	vdc_validate_geometry(vdc_t *vdc);
197 static void	vdc_validate(vdc_t *vdc);
198 static void	vdc_validate_task(void *arg);
199 static int	vdc_null_copy_func(vdc_t *vdc, void *from, void *to,
200 		    int mode, int dir);
201 static int	vdc_get_wce_convert(vdc_t *vdc, void *from, void *to,
202 		    int mode, int dir);
203 static int	vdc_set_wce_convert(vdc_t *vdc, void *from, void *to,
204 		    int mode, int dir);
205 static int	vdc_get_vtoc_convert(vdc_t *vdc, void *from, void *to,
206 		    int mode, int dir);
207 static int	vdc_set_vtoc_convert(vdc_t *vdc, void *from, void *to,
208 		    int mode, int dir);
209 static int	vdc_get_extvtoc_convert(vdc_t *vdc, void *from, void *to,
210 		    int mode, int dir);
211 static int	vdc_set_extvtoc_convert(vdc_t *vdc, void *from, void *to,
212 		    int mode, int dir);
213 static int	vdc_get_geom_convert(vdc_t *vdc, void *from, void *to,
214 		    int mode, int dir);
215 static int	vdc_set_geom_convert(vdc_t *vdc, void *from, void *to,
216 		    int mode, int dir);
217 static int	vdc_get_efi_convert(vdc_t *vdc, void *from, void *to,
218 		    int mode, int dir);
219 static int	vdc_set_efi_convert(vdc_t *vdc, void *from, void *to,
220 		    int mode, int dir);
221 
222 static void 	vdc_ownership_update(vdc_t *vdc, int ownership_flags);
223 static int	vdc_access_set(vdc_t *vdc, uint64_t flags, int mode);
224 static vdc_io_t	*vdc_failfast_io_queue(vdc_t *vdc, struct buf *buf);
225 static int	vdc_failfast_check_resv(vdc_t *vdc);
226 
227 /*
228  * Module variables
229  */
230 
231 /*
232  * Tunable variables to control how long vdc waits before timing out on
233  * various operations
234  */
235 static int	vdc_hshake_retries = 3;
236 
237 static int	vdc_timeout = 0; /* units: seconds */
238 static int 	vdc_ldcup_timeout = 1; /* units: seconds */
239 
240 static uint64_t vdc_hz_min_ldc_delay;
241 static uint64_t vdc_min_timeout_ldc = 1 * MILLISEC;
242 static uint64_t vdc_hz_max_ldc_delay;
243 static uint64_t vdc_max_timeout_ldc = 100 * MILLISEC;
244 
245 static uint64_t vdc_ldc_read_init_delay = 1 * MILLISEC;
246 static uint64_t vdc_ldc_read_max_delay = 100 * MILLISEC;
247 
248 /* values for dumping - need to run in a tighter loop */
249 static uint64_t	vdc_usec_timeout_dump = 100 * MILLISEC;	/* 0.1s units: ns */
250 static int	vdc_dump_retries = 100;
251 
252 static uint16_t	vdc_scsi_timeout = 60;	/* 60s units: seconds  */
253 
254 static uint64_t vdc_ownership_delay = 6 * MICROSEC; /* 6s units: usec */
255 
256 /* Count of the number of vdc instances attached */
257 static volatile uint32_t	vdc_instance_count = 0;
258 
259 /* Tunable to log all SCSI errors */
260 static boolean_t vdc_scsi_log_error = B_FALSE;
261 
262 /* Soft state pointer */
263 static void	*vdc_state;
264 
265 /*
266  * Controlling the verbosity of the error/debug messages
267  *
268  * vdc_msglevel - controls level of messages
269  * vdc_matchinst - 64-bit variable where each bit corresponds
270  *                 to the vdc instance the vdc_msglevel applies.
271  */
272 int		vdc_msglevel = 0x0;
273 uint64_t	vdc_matchinst = 0ull;
274 
275 /*
276  * Supported vDisk protocol version pairs.
277  *
278  * The first array entry is the latest and preferred version.
279  */
280 static const vio_ver_t	vdc_version[] = {{1, 1}};
281 
282 static struct cb_ops vdc_cb_ops = {
283 	vdc_open,	/* cb_open */
284 	vdc_close,	/* cb_close */
285 	vdc_strategy,	/* cb_strategy */
286 	vdc_print,	/* cb_print */
287 	vdc_dump,	/* cb_dump */
288 	vdc_read,	/* cb_read */
289 	vdc_write,	/* cb_write */
290 	vdc_ioctl,	/* cb_ioctl */
291 	nodev,		/* cb_devmap */
292 	nodev,		/* cb_mmap */
293 	nodev,		/* cb_segmap */
294 	nochpoll,	/* cb_chpoll */
295 	vdc_prop_op,	/* cb_prop_op */
296 	NULL,		/* cb_str */
297 	D_MP | D_64BIT,	/* cb_flag */
298 	CB_REV,		/* cb_rev */
299 	vdc_aread,	/* cb_aread */
300 	vdc_awrite	/* cb_awrite */
301 };
302 
303 static struct dev_ops vdc_ops = {
304 	DEVO_REV,	/* devo_rev */
305 	0,		/* devo_refcnt */
306 	vdc_getinfo,	/* devo_getinfo */
307 	nulldev,	/* devo_identify */
308 	nulldev,	/* devo_probe */
309 	vdc_attach,	/* devo_attach */
310 	vdc_detach,	/* devo_detach */
311 	nodev,		/* devo_reset */
312 	&vdc_cb_ops,	/* devo_cb_ops */
313 	NULL,		/* devo_bus_ops */
314 	nulldev,	/* devo_power */
315 	ddi_quiesce_not_needed,	/* devo_quiesce */
316 };
317 
318 static struct modldrv modldrv = {
319 	&mod_driverops,
320 	"virtual disk client",
321 	&vdc_ops,
322 };
323 
324 static struct modlinkage modlinkage = {
325 	MODREV_1,
326 	&modldrv,
327 	NULL
328 };
329 
330 /* -------------------------------------------------------------------------- */
331 
332 /*
333  * Device Driver housekeeping and setup
334  */
335 
336 int
337 _init(void)
338 {
339 	int	status;
340 
341 	if ((status = ddi_soft_state_init(&vdc_state, sizeof (vdc_t), 1)) != 0)
342 		return (status);
343 	if ((status = mod_install(&modlinkage)) != 0)
344 		ddi_soft_state_fini(&vdc_state);
345 	return (status);
346 }
347 
348 int
349 _info(struct modinfo *modinfop)
350 {
351 	return (mod_info(&modlinkage, modinfop));
352 }
353 
354 int
355 _fini(void)
356 {
357 	int	status;
358 
359 	if ((status = mod_remove(&modlinkage)) != 0)
360 		return (status);
361 	ddi_soft_state_fini(&vdc_state);
362 	return (0);
363 }
364 
365 static int
366 vdc_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd,  void *arg, void **resultp)
367 {
368 	_NOTE(ARGUNUSED(dip))
369 
370 	int	instance = VDCUNIT((dev_t)arg);
371 	vdc_t	*vdc = NULL;
372 
373 	switch (cmd) {
374 	case DDI_INFO_DEVT2DEVINFO:
375 		if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
376 			*resultp = NULL;
377 			return (DDI_FAILURE);
378 		}
379 		*resultp = vdc->dip;
380 		return (DDI_SUCCESS);
381 	case DDI_INFO_DEVT2INSTANCE:
382 		*resultp = (void *)(uintptr_t)instance;
383 		return (DDI_SUCCESS);
384 	default:
385 		*resultp = NULL;
386 		return (DDI_FAILURE);
387 	}
388 }
389 
390 static int
391 vdc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
392 {
393 	kt_did_t failfast_tid, ownership_tid;
394 	int	instance;
395 	int	rv;
396 	vdc_server_t *srvr;
397 	vdc_t	*vdc = NULL;
398 
399 	switch (cmd) {
400 	case DDI_DETACH:
401 		/* the real work happens below */
402 		break;
403 	case DDI_SUSPEND:
404 		/* nothing to do for this non-device */
405 		return (DDI_SUCCESS);
406 	default:
407 		return (DDI_FAILURE);
408 	}
409 
410 	ASSERT(cmd == DDI_DETACH);
411 	instance = ddi_get_instance(dip);
412 	DMSGX(1, "[%d] Entered\n", instance);
413 
414 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
415 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
416 		return (DDI_FAILURE);
417 	}
418 
419 	/*
420 	 * This function is called when vdc is detached or if it has failed to
421 	 * attach. In that case, the attach may have fail before the vdisk type
422 	 * has been set so we can't call vdc_is_opened(). However as the attach
423 	 * has failed, we know that the vdisk is not opened and we can safely
424 	 * detach.
425 	 */
426 	if (vdc->vdisk_type != VD_DISK_TYPE_UNK && vdc_is_opened(vdc)) {
427 		DMSG(vdc, 0, "[%d] Cannot detach: device is open", instance);
428 		return (DDI_FAILURE);
429 	}
430 
431 	if (vdc->dkio_flush_pending) {
432 		DMSG(vdc, 0,
433 		    "[%d] Cannot detach: %d outstanding DKIO flushes\n",
434 		    instance, vdc->dkio_flush_pending);
435 		return (DDI_FAILURE);
436 	}
437 
438 	if (vdc->validate_pending) {
439 		DMSG(vdc, 0,
440 		    "[%d] Cannot detach: %d outstanding validate request\n",
441 		    instance, vdc->validate_pending);
442 		return (DDI_FAILURE);
443 	}
444 
445 	DMSG(vdc, 0, "[%d] proceeding...\n", instance);
446 
447 	/* If we took ownership, release ownership */
448 	mutex_enter(&vdc->ownership_lock);
449 	if (vdc->ownership & VDC_OWNERSHIP_GRANTED) {
450 		rv = vdc_access_set(vdc, VD_ACCESS_SET_CLEAR, FKIOCTL);
451 		if (rv == 0) {
452 			vdc_ownership_update(vdc, VDC_OWNERSHIP_NONE);
453 		}
454 	}
455 	mutex_exit(&vdc->ownership_lock);
456 
457 	/* mark instance as detaching */
458 	vdc->lifecycle	= VDC_LC_DETACHING;
459 
460 	/*
461 	 * Try and disable callbacks to prevent another handshake. We have to
462 	 * disable callbacks for all servers.
463 	 */
464 	for (srvr = vdc->server_list; srvr != NULL; srvr = srvr->next) {
465 		rv = ldc_set_cb_mode(srvr->ldc_handle, LDC_CB_DISABLE);
466 		DMSG(vdc, 0, "callback disabled (ldc=%lu, rv=%d)\n",
467 		    srvr->ldc_id, rv);
468 	}
469 
470 	if (vdc->initialized & VDC_THREAD) {
471 		mutex_enter(&vdc->read_lock);
472 		if ((vdc->read_state == VDC_READ_WAITING) ||
473 		    (vdc->read_state == VDC_READ_RESET)) {
474 			vdc->read_state = VDC_READ_RESET;
475 			cv_signal(&vdc->read_cv);
476 		}
477 
478 		mutex_exit(&vdc->read_lock);
479 
480 		/* wake up any thread waiting for connection to come online */
481 		mutex_enter(&vdc->lock);
482 		if (vdc->state == VDC_STATE_INIT_WAITING) {
483 			DMSG(vdc, 0,
484 			    "[%d] write reset - move to resetting state...\n",
485 			    instance);
486 			vdc->state = VDC_STATE_RESETTING;
487 			cv_signal(&vdc->initwait_cv);
488 		}
489 		mutex_exit(&vdc->lock);
490 
491 		/* now wait until state transitions to VDC_STATE_DETACH */
492 		thread_join(vdc->msg_proc_thr->t_did);
493 		ASSERT(vdc->state == VDC_STATE_DETACH);
494 		DMSG(vdc, 0, "[%d] Reset thread exit and join ..\n",
495 		    vdc->instance);
496 	}
497 
498 	mutex_enter(&vdc->lock);
499 
500 	if (vdc->initialized & VDC_DRING)
501 		vdc_destroy_descriptor_ring(vdc);
502 
503 	vdc_fini_ports(vdc);
504 
505 	if (vdc->failfast_thread) {
506 		failfast_tid = vdc->failfast_thread->t_did;
507 		vdc->failfast_interval = 0;
508 		cv_signal(&vdc->failfast_cv);
509 	} else {
510 		failfast_tid = 0;
511 	}
512 
513 	if (vdc->ownership & VDC_OWNERSHIP_WANTED) {
514 		ownership_tid = vdc->ownership_thread->t_did;
515 		vdc->ownership = VDC_OWNERSHIP_NONE;
516 		cv_signal(&vdc->ownership_cv);
517 	} else {
518 		ownership_tid = 0;
519 	}
520 
521 	mutex_exit(&vdc->lock);
522 
523 	if (failfast_tid != 0)
524 		thread_join(failfast_tid);
525 
526 	if (ownership_tid != 0)
527 		thread_join(ownership_tid);
528 
529 	if (vdc->initialized & VDC_MINOR)
530 		ddi_remove_minor_node(dip, NULL);
531 
532 	if (vdc->io_stats) {
533 		kstat_delete(vdc->io_stats);
534 		vdc->io_stats = NULL;
535 	}
536 
537 	if (vdc->err_stats) {
538 		kstat_delete(vdc->err_stats);
539 		vdc->err_stats = NULL;
540 	}
541 
542 	if (vdc->initialized & VDC_LOCKS) {
543 		mutex_destroy(&vdc->lock);
544 		mutex_destroy(&vdc->read_lock);
545 		mutex_destroy(&vdc->ownership_lock);
546 		cv_destroy(&vdc->initwait_cv);
547 		cv_destroy(&vdc->dring_free_cv);
548 		cv_destroy(&vdc->membind_cv);
549 		cv_destroy(&vdc->sync_pending_cv);
550 		cv_destroy(&vdc->sync_blocked_cv);
551 		cv_destroy(&vdc->read_cv);
552 		cv_destroy(&vdc->running_cv);
553 		cv_destroy(&vdc->ownership_cv);
554 		cv_destroy(&vdc->failfast_cv);
555 		cv_destroy(&vdc->failfast_io_cv);
556 	}
557 
558 	if (vdc->minfo)
559 		kmem_free(vdc->minfo, sizeof (struct dk_minfo));
560 
561 	if (vdc->cinfo)
562 		kmem_free(vdc->cinfo, sizeof (struct dk_cinfo));
563 
564 	if (vdc->vtoc)
565 		kmem_free(vdc->vtoc, sizeof (struct extvtoc));
566 
567 	if (vdc->geom)
568 		kmem_free(vdc->geom, sizeof (struct dk_geom));
569 
570 	if (vdc->devid) {
571 		ddi_devid_unregister(dip);
572 		ddi_devid_free(vdc->devid);
573 	}
574 
575 	if (vdc->initialized & VDC_SOFT_STATE)
576 		ddi_soft_state_free(vdc_state, instance);
577 
578 	DMSG(vdc, 0, "[%d] End %p\n", instance, (void *)vdc);
579 
580 	return (DDI_SUCCESS);
581 }
582 
583 
584 static int
585 vdc_do_attach(dev_info_t *dip)
586 {
587 	int		instance;
588 	vdc_t		*vdc = NULL;
589 	int		status;
590 	md_t		*mdp;
591 	mde_cookie_t	vd_node;
592 
593 	ASSERT(dip != NULL);
594 
595 	instance = ddi_get_instance(dip);
596 	if (ddi_soft_state_zalloc(vdc_state, instance) != DDI_SUCCESS) {
597 		cmn_err(CE_NOTE, "[%d] Couldn't alloc state structure",
598 		    instance);
599 		return (DDI_FAILURE);
600 	}
601 
602 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
603 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
604 		return (DDI_FAILURE);
605 	}
606 
607 	/*
608 	 * We assign the value to initialized in this case to zero out the
609 	 * variable and then set bits in it to indicate what has been done
610 	 */
611 	vdc->initialized = VDC_SOFT_STATE;
612 
613 	vdc_hz_min_ldc_delay = drv_usectohz(vdc_min_timeout_ldc);
614 	vdc_hz_max_ldc_delay = drv_usectohz(vdc_max_timeout_ldc);
615 
616 	vdc->dip	= dip;
617 	vdc->instance	= instance;
618 	vdc->vdisk_type	= VD_DISK_TYPE_UNK;
619 	vdc->vdisk_label = VD_DISK_LABEL_UNK;
620 	vdc->state	= VDC_STATE_INIT;
621 	vdc->lifecycle	= VDC_LC_ATTACHING;
622 	vdc->session_id = 0;
623 	vdc->block_size = DEV_BSIZE;
624 	vdc->max_xfer_sz = maxphys / DEV_BSIZE;
625 
626 	/*
627 	 * We assume, for now, that the vDisk server will export 'read'
628 	 * operations to us at a minimum (this is needed because of checks
629 	 * in vdc for supported operations early in the handshake process).
630 	 * The vDisk server will return ENOTSUP if this is not the case.
631 	 * The value will be overwritten during the attribute exchange with
632 	 * the bitmask of operations exported by server.
633 	 */
634 	vdc->operations = VD_OP_MASK_READ;
635 
636 	vdc->vtoc = NULL;
637 	vdc->geom = NULL;
638 	vdc->cinfo = NULL;
639 	vdc->minfo = NULL;
640 
641 	mutex_init(&vdc->lock, NULL, MUTEX_DRIVER, NULL);
642 	cv_init(&vdc->initwait_cv, NULL, CV_DRIVER, NULL);
643 	cv_init(&vdc->dring_free_cv, NULL, CV_DRIVER, NULL);
644 	cv_init(&vdc->membind_cv, NULL, CV_DRIVER, NULL);
645 	cv_init(&vdc->running_cv, NULL, CV_DRIVER, NULL);
646 
647 	vdc->threads_pending = 0;
648 	vdc->sync_op_pending = B_FALSE;
649 	vdc->sync_op_blocked = B_FALSE;
650 	cv_init(&vdc->sync_pending_cv, NULL, CV_DRIVER, NULL);
651 	cv_init(&vdc->sync_blocked_cv, NULL, CV_DRIVER, NULL);
652 
653 	mutex_init(&vdc->ownership_lock, NULL, MUTEX_DRIVER, NULL);
654 	cv_init(&vdc->ownership_cv, NULL, CV_DRIVER, NULL);
655 	cv_init(&vdc->failfast_cv, NULL, CV_DRIVER, NULL);
656 	cv_init(&vdc->failfast_io_cv, NULL, CV_DRIVER, NULL);
657 
658 	/* init blocking msg read functionality */
659 	mutex_init(&vdc->read_lock, NULL, MUTEX_DRIVER, NULL);
660 	cv_init(&vdc->read_cv, NULL, CV_DRIVER, NULL);
661 	vdc->read_state = VDC_READ_IDLE;
662 
663 	vdc->initialized |= VDC_LOCKS;
664 
665 	/* get device and port MD node for this disk instance */
666 	if (vdc_get_md_node(dip, &mdp, &vd_node) != 0) {
667 		cmn_err(CE_NOTE, "[%d] Could not get machine description node",
668 		    instance);
669 		return (DDI_FAILURE);
670 	}
671 
672 	if (vdc_init_ports(vdc, mdp, vd_node) != 0) {
673 		cmn_err(CE_NOTE, "[%d] Error initialising ports", instance);
674 		return (DDI_FAILURE);
675 	}
676 
677 	(void) md_fini_handle(mdp);
678 
679 	/* Create the kstats for saving the I/O statistics used by iostat(1M) */
680 	vdc_create_io_kstats(vdc);
681 	vdc_create_err_kstats(vdc);
682 
683 	/* Initialize remaining structures before starting the msg thread */
684 	vdc->vdisk_label = VD_DISK_LABEL_UNK;
685 	vdc->vtoc = kmem_zalloc(sizeof (struct extvtoc), KM_SLEEP);
686 	vdc->geom = kmem_zalloc(sizeof (struct dk_geom), KM_SLEEP);
687 	vdc->minfo = kmem_zalloc(sizeof (struct dk_minfo), KM_SLEEP);
688 
689 	/* initialize the thread responsible for managing state with server */
690 	vdc->msg_proc_thr = thread_create(NULL, 0, vdc_process_msg_thread,
691 	    vdc, 0, &p0, TS_RUN, minclsyspri);
692 	if (vdc->msg_proc_thr == NULL) {
693 		cmn_err(CE_NOTE, "[%d] Failed to create msg processing thread",
694 		    instance);
695 		return (DDI_FAILURE);
696 	}
697 
698 	vdc->initialized |= VDC_THREAD;
699 
700 	atomic_inc_32(&vdc_instance_count);
701 
702 	/*
703 	 * Check the disk label. This will send requests and do the handshake.
704 	 * We don't really care about the disk label now. What we really need is
705 	 * the handshake do be done so that we know the type of the disk (slice
706 	 * or full disk) and the appropriate device nodes can be created.
707 	 */
708 
709 	mutex_enter(&vdc->lock);
710 	(void) vdc_validate_geometry(vdc);
711 	mutex_exit(&vdc->lock);
712 
713 	/*
714 	 * Now that we have the device info we can create the device nodes
715 	 */
716 	status = vdc_create_device_nodes(vdc);
717 	if (status) {
718 		DMSG(vdc, 0, "[%d] Failed to create device nodes",
719 		    instance);
720 		goto return_status;
721 	}
722 
723 	/*
724 	 * Setup devid
725 	 */
726 	if (vdc_setup_devid(vdc)) {
727 		DMSG(vdc, 0, "[%d] No device id available\n", instance);
728 	}
729 
730 	/*
731 	 * Fill in the fields of the error statistics kstat that were not
732 	 * available when creating the kstat
733 	 */
734 	vdc_set_err_kstats(vdc);
735 
736 	ddi_report_dev(dip);
737 	vdc->lifecycle	= VDC_LC_ONLINE;
738 	DMSG(vdc, 0, "[%d] Attach tasks successful\n", instance);
739 
740 return_status:
741 	DMSG(vdc, 0, "[%d] Attach completed\n", instance);
742 	return (status);
743 }
744 
745 static int
746 vdc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
747 {
748 	int	status;
749 
750 	switch (cmd) {
751 	case DDI_ATTACH:
752 		if ((status = vdc_do_attach(dip)) != 0)
753 			(void) vdc_detach(dip, DDI_DETACH);
754 		return (status);
755 	case DDI_RESUME:
756 		/* nothing to do for this non-device */
757 		return (DDI_SUCCESS);
758 	default:
759 		return (DDI_FAILURE);
760 	}
761 }
762 
763 static int
764 vdc_do_ldc_init(vdc_t *vdc, vdc_server_t *srvr)
765 {
766 	int			status = 0;
767 	ldc_status_t		ldc_state;
768 	ldc_attr_t		ldc_attr;
769 
770 	ASSERT(vdc != NULL);
771 	ASSERT(srvr != NULL);
772 
773 	ldc_attr.devclass = LDC_DEV_BLK;
774 	ldc_attr.instance = vdc->instance;
775 	ldc_attr.mode = LDC_MODE_UNRELIABLE;	/* unreliable transport */
776 	ldc_attr.mtu = VD_LDC_MTU;
777 
778 	if ((srvr->state & VDC_LDC_INIT) == 0) {
779 		status = ldc_init(srvr->ldc_id, &ldc_attr,
780 		    &srvr->ldc_handle);
781 		if (status != 0) {
782 			DMSG(vdc, 0, "[%d] ldc_init(chan %ld) returned %d",
783 			    vdc->instance, srvr->ldc_id, status);
784 			return (status);
785 		}
786 		srvr->state |= VDC_LDC_INIT;
787 	}
788 	status = ldc_status(srvr->ldc_handle, &ldc_state);
789 	if (status != 0) {
790 		DMSG(vdc, 0, "[%d] Cannot discover LDC status [err=%d]",
791 		    vdc->instance, status);
792 		goto init_exit;
793 	}
794 	srvr->ldc_state = ldc_state;
795 
796 	if ((srvr->state & VDC_LDC_CB) == 0) {
797 		status = ldc_reg_callback(srvr->ldc_handle, vdc_handle_cb,
798 		    (caddr_t)srvr);
799 		if (status != 0) {
800 			DMSG(vdc, 0, "[%d] LDC callback reg. failed (%d)",
801 			    vdc->instance, status);
802 			goto init_exit;
803 		}
804 		srvr->state |= VDC_LDC_CB;
805 	}
806 
807 	/*
808 	 * At this stage we have initialised LDC, we will now try and open
809 	 * the connection.
810 	 */
811 	if (srvr->ldc_state == LDC_INIT) {
812 		status = ldc_open(srvr->ldc_handle);
813 		if (status != 0) {
814 			DMSG(vdc, 0, "[%d] ldc_open(chan %ld) returned %d",
815 			    vdc->instance, srvr->ldc_id, status);
816 			goto init_exit;
817 		}
818 		srvr->state |= VDC_LDC_OPEN;
819 	}
820 
821 init_exit:
822 	if (status) {
823 		vdc_terminate_ldc(vdc, srvr);
824 	}
825 
826 	return (status);
827 }
828 
829 static int
830 vdc_start_ldc_connection(vdc_t *vdc)
831 {
832 	int		status = 0;
833 
834 	ASSERT(vdc != NULL);
835 
836 	ASSERT(MUTEX_HELD(&vdc->lock));
837 
838 	status = vdc_do_ldc_up(vdc);
839 
840 	DMSG(vdc, 0, "[%d] Finished bringing up LDC\n", vdc->instance);
841 
842 	return (status);
843 }
844 
845 static int
846 vdc_stop_ldc_connection(vdc_t *vdcp)
847 {
848 	int	status;
849 
850 	ASSERT(vdcp != NULL);
851 
852 	ASSERT(MUTEX_HELD(&vdcp->lock));
853 
854 	DMSG(vdcp, 0, ": Resetting connection to vDisk server : state %d\n",
855 	    vdcp->state);
856 
857 	status = ldc_down(vdcp->curr_server->ldc_handle);
858 	DMSG(vdcp, 0, "ldc_down() = %d\n", status);
859 
860 	vdcp->initialized &= ~VDC_HANDSHAKE;
861 	DMSG(vdcp, 0, "initialized=%x\n", vdcp->initialized);
862 
863 	return (status);
864 }
865 
866 static void
867 vdc_create_io_kstats(vdc_t *vdc)
868 {
869 	if (vdc->io_stats != NULL) {
870 		DMSG(vdc, 0, "[%d] I/O kstat already exists\n", vdc->instance);
871 		return;
872 	}
873 
874 	vdc->io_stats = kstat_create(VDC_DRIVER_NAME, vdc->instance, NULL,
875 	    "disk", KSTAT_TYPE_IO, 1, KSTAT_FLAG_PERSISTENT);
876 	if (vdc->io_stats != NULL) {
877 		vdc->io_stats->ks_lock = &vdc->lock;
878 		kstat_install(vdc->io_stats);
879 	} else {
880 		cmn_err(CE_NOTE, "[%d] Failed to create kstat: I/O statistics"
881 		    " will not be gathered", vdc->instance);
882 	}
883 }
884 
885 static void
886 vdc_create_err_kstats(vdc_t *vdc)
887 {
888 	vd_err_stats_t	*stp;
889 	char	kstatmodule_err[KSTAT_STRLEN];
890 	char	kstatname[KSTAT_STRLEN];
891 	int	ndata = (sizeof (vd_err_stats_t) / sizeof (kstat_named_t));
892 	int	instance = vdc->instance;
893 
894 	if (vdc->err_stats != NULL) {
895 		DMSG(vdc, 0, "[%d] ERR kstat already exists\n", vdc->instance);
896 		return;
897 	}
898 
899 	(void) snprintf(kstatmodule_err, sizeof (kstatmodule_err),
900 	    "%serr", VDC_DRIVER_NAME);
901 	(void) snprintf(kstatname, sizeof (kstatname),
902 	    "%s%d,err", VDC_DRIVER_NAME, instance);
903 
904 	vdc->err_stats = kstat_create(kstatmodule_err, instance, kstatname,
905 	    "device_error", KSTAT_TYPE_NAMED, ndata, KSTAT_FLAG_PERSISTENT);
906 
907 	if (vdc->err_stats == NULL) {
908 		cmn_err(CE_NOTE, "[%d] Failed to create kstat: Error statistics"
909 		    " will not be gathered", instance);
910 		return;
911 	}
912 
913 	stp = (vd_err_stats_t *)vdc->err_stats->ks_data;
914 	kstat_named_init(&stp->vd_softerrs,	"Soft Errors",
915 	    KSTAT_DATA_UINT32);
916 	kstat_named_init(&stp->vd_transerrs,	"Transport Errors",
917 	    KSTAT_DATA_UINT32);
918 	kstat_named_init(&stp->vd_protoerrs,	"Protocol Errors",
919 	    KSTAT_DATA_UINT32);
920 	kstat_named_init(&stp->vd_vid,		"Vendor",
921 	    KSTAT_DATA_CHAR);
922 	kstat_named_init(&stp->vd_pid,		"Product",
923 	    KSTAT_DATA_CHAR);
924 	kstat_named_init(&stp->vd_capacity,	"Size",
925 	    KSTAT_DATA_ULONGLONG);
926 
927 	vdc->err_stats->ks_update  = nulldev;
928 
929 	kstat_install(vdc->err_stats);
930 }
931 
932 static void
933 vdc_set_err_kstats(vdc_t *vdc)
934 {
935 	vd_err_stats_t  *stp;
936 
937 	if (vdc->err_stats == NULL)
938 		return;
939 
940 	mutex_enter(&vdc->lock);
941 
942 	stp = (vd_err_stats_t *)vdc->err_stats->ks_data;
943 	ASSERT(stp != NULL);
944 
945 	stp->vd_capacity.value.ui64 = vdc->vdisk_size * vdc->block_size;
946 	(void) strcpy(stp->vd_vid.value.c, "SUN");
947 	(void) strcpy(stp->vd_pid.value.c, "VDSK");
948 
949 	mutex_exit(&vdc->lock);
950 }
951 
952 static int
953 vdc_create_device_nodes_efi(vdc_t *vdc)
954 {
955 	ddi_remove_minor_node(vdc->dip, "h");
956 	ddi_remove_minor_node(vdc->dip, "h,raw");
957 
958 	if (ddi_create_minor_node(vdc->dip, "wd", S_IFBLK,
959 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
960 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
961 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'wd'",
962 		    vdc->instance);
963 		return (EIO);
964 	}
965 
966 	/* if any device node is created we set this flag */
967 	vdc->initialized |= VDC_MINOR;
968 
969 	if (ddi_create_minor_node(vdc->dip, "wd,raw", S_IFCHR,
970 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
971 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
972 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'wd,raw'",
973 		    vdc->instance);
974 		return (EIO);
975 	}
976 
977 	return (0);
978 }
979 
980 static int
981 vdc_create_device_nodes_vtoc(vdc_t *vdc)
982 {
983 	ddi_remove_minor_node(vdc->dip, "wd");
984 	ddi_remove_minor_node(vdc->dip, "wd,raw");
985 
986 	if (ddi_create_minor_node(vdc->dip, "h", S_IFBLK,
987 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
988 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
989 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'h'",
990 		    vdc->instance);
991 		return (EIO);
992 	}
993 
994 	/* if any device node is created we set this flag */
995 	vdc->initialized |= VDC_MINOR;
996 
997 	if (ddi_create_minor_node(vdc->dip, "h,raw", S_IFCHR,
998 	    VD_MAKE_DEV(vdc->instance, VD_EFI_WD_SLICE),
999 	    DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
1000 		cmn_err(CE_NOTE, "[%d] Couldn't add block node 'h,raw'",
1001 		    vdc->instance);
1002 		return (EIO);
1003 	}
1004 
1005 	return (0);
1006 }
1007 
1008 /*
1009  * Function:
1010  *	vdc_create_device_nodes
1011  *
1012  * Description:
1013  *	This function creates the block and character device nodes under
1014  *	/devices. It is called as part of the attach(9E) of the instance
1015  *	during the handshake with vds after vds has sent the attributes
1016  *	to vdc.
1017  *
1018  *	If the device is of type VD_DISK_TYPE_SLICE then the minor node
1019  *	of 2 is used in keeping with the Solaris convention that slice 2
1020  *	refers to a whole disk. Slices start at 'a'
1021  *
1022  * Parameters:
1023  *	vdc 		- soft state pointer
1024  *
1025  * Return Values
1026  *	0		- Success
1027  *	EIO		- Failed to create node
1028  *	EINVAL		- Unknown type of disk exported
1029  */
1030 static int
1031 vdc_create_device_nodes(vdc_t *vdc)
1032 {
1033 	char		name[sizeof ("s,raw")];
1034 	dev_info_t	*dip = NULL;
1035 	int		instance, status;
1036 	int		num_slices = 1;
1037 	int		i;
1038 
1039 	ASSERT(vdc != NULL);
1040 
1041 	instance = vdc->instance;
1042 	dip = vdc->dip;
1043 
1044 	switch (vdc->vdisk_type) {
1045 	case VD_DISK_TYPE_DISK:
1046 		num_slices = V_NUMPAR;
1047 		break;
1048 	case VD_DISK_TYPE_SLICE:
1049 		num_slices = 1;
1050 		break;
1051 	case VD_DISK_TYPE_UNK:
1052 	default:
1053 		return (EINVAL);
1054 	}
1055 
1056 	/*
1057 	 * Minor nodes are different for EFI disks: EFI disks do not have
1058 	 * a minor node 'g' for the minor number corresponding to slice
1059 	 * VD_EFI_WD_SLICE (slice 7) instead they have a minor node 'wd'
1060 	 * representing the whole disk.
1061 	 */
1062 	for (i = 0; i < num_slices; i++) {
1063 
1064 		if (i == VD_EFI_WD_SLICE) {
1065 			if (vdc->vdisk_label == VD_DISK_LABEL_EFI)
1066 				status = vdc_create_device_nodes_efi(vdc);
1067 			else
1068 				status = vdc_create_device_nodes_vtoc(vdc);
1069 			if (status != 0)
1070 				return (status);
1071 			continue;
1072 		}
1073 
1074 		(void) snprintf(name, sizeof (name), "%c", 'a' + i);
1075 		if (ddi_create_minor_node(dip, name, S_IFBLK,
1076 		    VD_MAKE_DEV(instance, i), DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
1077 			cmn_err(CE_NOTE, "[%d] Couldn't add block node '%s'",
1078 			    instance, name);
1079 			return (EIO);
1080 		}
1081 
1082 		/* if any device node is created we set this flag */
1083 		vdc->initialized |= VDC_MINOR;
1084 
1085 		(void) snprintf(name, sizeof (name), "%c%s", 'a' + i, ",raw");
1086 
1087 		if (ddi_create_minor_node(dip, name, S_IFCHR,
1088 		    VD_MAKE_DEV(instance, i), DDI_NT_BLOCK, 0) != DDI_SUCCESS) {
1089 			cmn_err(CE_NOTE, "[%d] Couldn't add raw node '%s'",
1090 			    instance, name);
1091 			return (EIO);
1092 		}
1093 	}
1094 
1095 	return (0);
1096 }
1097 
1098 /*
1099  * Driver prop_op(9e) entry point function. Return the number of blocks for
1100  * the partition in question or forward the request to the property facilities.
1101  */
1102 static int
1103 vdc_prop_op(dev_t dev, dev_info_t *dip, ddi_prop_op_t prop_op, int mod_flags,
1104     char *name, caddr_t valuep, int *lengthp)
1105 {
1106 	int instance = ddi_get_instance(dip);
1107 	vdc_t *vdc;
1108 	uint64_t nblocks;
1109 	uint_t blksize;
1110 
1111 	vdc = ddi_get_soft_state(vdc_state, instance);
1112 
1113 	if (dev == DDI_DEV_T_ANY || vdc == NULL) {
1114 		return (ddi_prop_op(dev, dip, prop_op, mod_flags,
1115 		    name, valuep, lengthp));
1116 	}
1117 
1118 	mutex_enter(&vdc->lock);
1119 	(void) vdc_validate_geometry(vdc);
1120 	if (vdc->vdisk_label == VD_DISK_LABEL_UNK) {
1121 		mutex_exit(&vdc->lock);
1122 		return (ddi_prop_op(dev, dip, prop_op, mod_flags,
1123 		    name, valuep, lengthp));
1124 	}
1125 	nblocks = vdc->slice[VDCPART(dev)].nblocks;
1126 	blksize = vdc->block_size;
1127 	mutex_exit(&vdc->lock);
1128 
1129 	return (ddi_prop_op_nblocks_blksize(dev, dip, prop_op, mod_flags,
1130 	    name, valuep, lengthp, nblocks, blksize));
1131 }
1132 
1133 /*
1134  * Function:
1135  *	vdc_is_opened
1136  *
1137  * Description:
1138  *	This function checks if any slice of a given virtual disk is
1139  *	currently opened.
1140  *
1141  * Parameters:
1142  *	vdc 		- soft state pointer
1143  *
1144  * Return Values
1145  *	B_TRUE		- at least one slice is opened.
1146  *	B_FALSE		- no slice is opened.
1147  */
1148 static boolean_t
1149 vdc_is_opened(vdc_t *vdc)
1150 {
1151 	int i, nslices;
1152 
1153 	switch (vdc->vdisk_type) {
1154 	case VD_DISK_TYPE_DISK:
1155 		nslices = V_NUMPAR;
1156 		break;
1157 	case VD_DISK_TYPE_SLICE:
1158 		nslices = 1;
1159 		break;
1160 	case VD_DISK_TYPE_UNK:
1161 	default:
1162 		ASSERT(0);
1163 	}
1164 
1165 	/* check if there's any layered open */
1166 	for (i = 0; i < nslices; i++) {
1167 		if (vdc->open_lyr[i] > 0)
1168 			return (B_TRUE);
1169 	}
1170 
1171 	/* check if there is any other kind of open */
1172 	for (i = 0; i < OTYPCNT; i++) {
1173 		if (vdc->open[i] != 0)
1174 			return (B_TRUE);
1175 	}
1176 
1177 	return (B_FALSE);
1178 }
1179 
1180 static int
1181 vdc_mark_opened(vdc_t *vdc, int slice, int flag, int otyp)
1182 {
1183 	uint8_t slicemask;
1184 	int i;
1185 
1186 	ASSERT(otyp < OTYPCNT);
1187 	ASSERT(slice < V_NUMPAR);
1188 	ASSERT(MUTEX_HELD(&vdc->lock));
1189 
1190 	slicemask = 1 << slice;
1191 
1192 	/* check if slice is already exclusively opened */
1193 	if (vdc->open_excl & slicemask)
1194 		return (EBUSY);
1195 
1196 	/* if open exclusive, check if slice is already opened */
1197 	if (flag & FEXCL) {
1198 		if (vdc->open_lyr[slice] > 0)
1199 			return (EBUSY);
1200 		for (i = 0; i < OTYPCNT; i++) {
1201 			if (vdc->open[i] & slicemask)
1202 				return (EBUSY);
1203 		}
1204 		vdc->open_excl |= slicemask;
1205 	}
1206 
1207 	/* mark slice as opened */
1208 	if (otyp == OTYP_LYR) {
1209 		vdc->open_lyr[slice]++;
1210 	} else {
1211 		vdc->open[otyp] |= slicemask;
1212 	}
1213 
1214 	return (0);
1215 }
1216 
1217 static void
1218 vdc_mark_closed(vdc_t *vdc, int slice, int flag, int otyp)
1219 {
1220 	uint8_t slicemask;
1221 
1222 	ASSERT(otyp < OTYPCNT);
1223 	ASSERT(slice < V_NUMPAR);
1224 	ASSERT(MUTEX_HELD(&vdc->lock));
1225 
1226 	slicemask = 1 << slice;
1227 
1228 	if (otyp == OTYP_LYR) {
1229 		ASSERT(vdc->open_lyr[slice] > 0);
1230 		vdc->open_lyr[slice]--;
1231 	} else {
1232 		vdc->open[otyp] &= ~slicemask;
1233 	}
1234 
1235 	if (flag & FEXCL)
1236 		vdc->open_excl &= ~slicemask;
1237 }
1238 
1239 static int
1240 vdc_open(dev_t *dev, int flag, int otyp, cred_t *cred)
1241 {
1242 	_NOTE(ARGUNUSED(cred))
1243 
1244 	int	instance, nodelay;
1245 	int	slice, status = 0;
1246 	vdc_t	*vdc;
1247 
1248 	ASSERT(dev != NULL);
1249 	instance = VDCUNIT(*dev);
1250 
1251 	if (otyp >= OTYPCNT)
1252 		return (EINVAL);
1253 
1254 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1255 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1256 		return (ENXIO);
1257 	}
1258 
1259 	DMSG(vdc, 0, "minor = %d flag = %x, otyp = %x\n",
1260 	    getminor(*dev), flag, otyp);
1261 
1262 	slice = VDCPART(*dev);
1263 
1264 	nodelay = flag & (FNDELAY | FNONBLOCK);
1265 
1266 	if ((flag & FWRITE) && (!nodelay) &&
1267 	    !(VD_OP_SUPPORTED(vdc->operations, VD_OP_BWRITE))) {
1268 		return (EROFS);
1269 	}
1270 
1271 	mutex_enter(&vdc->lock);
1272 
1273 	status = vdc_mark_opened(vdc, slice, flag, otyp);
1274 
1275 	if (status != 0) {
1276 		mutex_exit(&vdc->lock);
1277 		return (status);
1278 	}
1279 
1280 	if (nodelay) {
1281 
1282 		/* don't resubmit a validate request if there's already one */
1283 		if (vdc->validate_pending > 0) {
1284 			mutex_exit(&vdc->lock);
1285 			return (0);
1286 		}
1287 
1288 		/* call vdc_validate() asynchronously to avoid blocking */
1289 		if (taskq_dispatch(system_taskq, vdc_validate_task,
1290 		    (void *)vdc, TQ_NOSLEEP) == NULL) {
1291 			vdc_mark_closed(vdc, slice, flag, otyp);
1292 			mutex_exit(&vdc->lock);
1293 			return (ENXIO);
1294 		}
1295 
1296 		vdc->validate_pending++;
1297 		mutex_exit(&vdc->lock);
1298 		return (0);
1299 	}
1300 
1301 	mutex_exit(&vdc->lock);
1302 
1303 	vdc_validate(vdc);
1304 
1305 	mutex_enter(&vdc->lock);
1306 
1307 	if (vdc->vdisk_label == VD_DISK_LABEL_UNK ||
1308 	    vdc->slice[slice].nblocks == 0) {
1309 		vdc_mark_closed(vdc, slice, flag, otyp);
1310 		status = EIO;
1311 	}
1312 
1313 	mutex_exit(&vdc->lock);
1314 
1315 	return (status);
1316 }
1317 
1318 static int
1319 vdc_close(dev_t dev, int flag, int otyp, cred_t *cred)
1320 {
1321 	_NOTE(ARGUNUSED(cred))
1322 
1323 	int	instance;
1324 	int	slice;
1325 	int	rv, rval;
1326 	vdc_t	*vdc;
1327 
1328 	instance = VDCUNIT(dev);
1329 
1330 	if (otyp >= OTYPCNT)
1331 		return (EINVAL);
1332 
1333 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1334 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1335 		return (ENXIO);
1336 	}
1337 
1338 	DMSG(vdc, 0, "[%d] flag = %x, otyp = %x\n", instance, flag, otyp);
1339 
1340 	slice = VDCPART(dev);
1341 
1342 	/*
1343 	 * Attempt to flush the W$ on a close operation. If this is
1344 	 * not a supported IOCTL command or the backing device is read-only
1345 	 * do not fail the close operation.
1346 	 */
1347 	rv = vd_process_ioctl(dev, DKIOCFLUSHWRITECACHE, NULL, FKIOCTL, &rval);
1348 
1349 	if (rv != 0 && rv != ENOTSUP && rv != ENOTTY && rv != EROFS) {
1350 		DMSG(vdc, 0, "[%d] flush failed with error %d on close\n",
1351 		    instance, rv);
1352 		return (EIO);
1353 	}
1354 
1355 	mutex_enter(&vdc->lock);
1356 	vdc_mark_closed(vdc, slice, flag, otyp);
1357 	mutex_exit(&vdc->lock);
1358 
1359 	return (0);
1360 }
1361 
1362 static int
1363 vdc_ioctl(dev_t dev, int cmd, intptr_t arg, int mode, cred_t *credp, int *rvalp)
1364 {
1365 	_NOTE(ARGUNUSED(credp))
1366 
1367 	return (vd_process_ioctl(dev, cmd, (caddr_t)arg, mode, rvalp));
1368 }
1369 
1370 static int
1371 vdc_print(dev_t dev, char *str)
1372 {
1373 	cmn_err(CE_NOTE, "vdc%d:  %s", VDCUNIT(dev), str);
1374 	return (0);
1375 }
1376 
1377 static int
1378 vdc_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk)
1379 {
1380 	int	rv;
1381 	size_t	nbytes = nblk * DEV_BSIZE;
1382 	int	instance = VDCUNIT(dev);
1383 	vdc_t	*vdc = NULL;
1384 
1385 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1386 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1387 		return (ENXIO);
1388 	}
1389 
1390 	DMSG(vdc, 2, "[%d] dump %ld bytes at block 0x%lx : addr=0x%p\n",
1391 	    instance, nbytes, blkno, (void *)addr);
1392 	rv = vdc_send_request(vdc, VD_OP_BWRITE, addr, nbytes,
1393 	    VDCPART(dev), blkno, CB_STRATEGY, 0, VIO_write_dir);
1394 	if (rv) {
1395 		DMSG(vdc, 0, "Failed to do a disk dump (err=%d)\n", rv);
1396 		return (rv);
1397 	}
1398 
1399 	if (ddi_in_panic())
1400 		(void) vdc_drain_response(vdc, NULL);
1401 
1402 	DMSG(vdc, 0, "[%d] End\n", instance);
1403 
1404 	return (0);
1405 }
1406 
1407 /* -------------------------------------------------------------------------- */
1408 
1409 /*
1410  * Disk access routines
1411  *
1412  */
1413 
1414 /*
1415  * vdc_strategy()
1416  *
1417  * Return Value:
1418  *	0:	As per strategy(9E), the strategy() function must return 0
1419  *		[ bioerror(9f) sets b_flags to the proper error code ]
1420  */
1421 static int
1422 vdc_strategy(struct buf *buf)
1423 {
1424 	int	rv = -1;
1425 	vdc_t	*vdc = NULL;
1426 	int	instance = VDCUNIT(buf->b_edev);
1427 	int	op = (buf->b_flags & B_READ) ? VD_OP_BREAD : VD_OP_BWRITE;
1428 	int	slice;
1429 
1430 	if ((vdc = ddi_get_soft_state(vdc_state, instance)) == NULL) {
1431 		cmn_err(CE_NOTE, "[%d] Couldn't get state structure", instance);
1432 		bioerror(buf, ENXIO);
1433 		biodone(buf);
1434 		return (0);
1435 	}
1436 
1437 	DMSG(vdc, 2, "[%d] %s %ld bytes at block %llx : b_addr=0x%p\n",
1438 	    instance, (buf->b_flags & B_READ) ? "Read" : "Write",
1439 	    buf->b_bcount, buf->b_lblkno, (void *)buf->b_un.b_addr);
1440 
1441 	bp_mapin(buf);
1442 
1443 	if ((long)buf->b_private == VD_SLICE_NONE) {
1444 		/* I/O using an absolute disk offset */
1445 		slice = VD_SLICE_NONE;
1446 	} else {
1447 		slice = VDCPART(buf->b_edev);
1448 	}
1449 
1450 	rv = vdc_send_request(vdc, op, (caddr_t)buf->b_un.b_addr,
1451 	    buf->b_bcount, slice, buf->b_lblkno,
1452 	    CB_STRATEGY, buf, (op == VD_OP_BREAD) ? VIO_read_dir :
1453 	    VIO_write_dir);
1454 
1455 	/*
1456 	 * If the request was successfully sent, the strategy call returns and
1457 	 * the ACK handler calls the bioxxx functions when the vDisk server is
1458 	 * done otherwise we handle the error here.
1459 	 */
1460 	if (rv) {
1461 		DMSG(vdc, 0, "Failed to read/write (err=%d)\n", rv);
1462 		bioerror(buf, rv);
1463 		biodone(buf);
1464 	} else if (ddi_in_panic()) {
1465 		(void) vdc_drain_response(vdc, buf);
1466 	}
1467 
1468 	return (0);
1469 }
1470 
1471 /*
1472  * Function:
1473  *	vdc_min
1474  *
1475  * Description:
1476  *	Routine to limit the size of a data transfer. Used in
1477  *	conjunction with physio(9F).
1478  *
1479  * Arguments:
1480  *	bp - pointer to the indicated buf(9S) struct.
1481  *
1482  */
1483 static void
1484 vdc_min(struct buf *bufp)
1485 {
1486 	vdc_t	*vdc = NULL;
1487 	int	instance = VDCUNIT(bufp->b_edev);
1488 
1489 	vdc = ddi_get_soft_state(vdc_state, instance);
1490 	VERIFY(vdc != NULL);
1491 
1492 	if (bufp->b_bcount > (vdc->max_xfer_sz * vdc->block_size)) {
1493 		bufp->b_bcount = vdc->max_xfer_sz * vdc->block_size;
1494 	}
1495 }
1496 
1497 static int
1498 vdc_read(dev_t dev, struct uio *uio, cred_t *cred)
1499 {
1500 	_NOTE(ARGUNUSED(cred))
1501 
1502 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1503 	return (physio(vdc_strategy, NULL, dev, B_READ, vdc_min, uio));
1504 }
1505 
1506 static int
1507 vdc_write(dev_t dev, struct uio *uio, cred_t *cred)
1508 {
1509 	_NOTE(ARGUNUSED(cred))
1510 
1511 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1512 	return (physio(vdc_strategy, NULL, dev, B_WRITE, vdc_min, uio));
1513 }
1514 
1515 static int
1516 vdc_aread(dev_t dev, struct aio_req *aio, cred_t *cred)
1517 {
1518 	_NOTE(ARGUNUSED(cred))
1519 
1520 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1521 	return (aphysio(vdc_strategy, anocancel, dev, B_READ, vdc_min, aio));
1522 }
1523 
1524 static int
1525 vdc_awrite(dev_t dev, struct aio_req *aio, cred_t *cred)
1526 {
1527 	_NOTE(ARGUNUSED(cred))
1528 
1529 	DMSGX(1, "[%d] Entered", VDCUNIT(dev));
1530 	return (aphysio(vdc_strategy, anocancel, dev, B_WRITE, vdc_min, aio));
1531 }
1532 
1533 
1534 /* -------------------------------------------------------------------------- */
1535 
1536 /*
1537  * Handshake support
1538  */
1539 
1540 
1541 /*
1542  * Function:
1543  *	vdc_init_ver_negotiation()
1544  *
1545  * Description:
1546  *
1547  * Arguments:
1548  *	vdc	- soft state pointer for this instance of the device driver.
1549  *
1550  * Return Code:
1551  *	0	- Success
1552  */
1553 static int
1554 vdc_init_ver_negotiation(vdc_t *vdc, vio_ver_t ver)
1555 {
1556 	vio_ver_msg_t	pkt;
1557 	size_t		msglen = sizeof (pkt);
1558 	int		status = -1;
1559 
1560 	ASSERT(vdc != NULL);
1561 	ASSERT(mutex_owned(&vdc->lock));
1562 
1563 	DMSG(vdc, 0, "[%d] Entered.\n", vdc->instance);
1564 
1565 	/*
1566 	 * set the Session ID to a unique value
1567 	 * (the lower 32 bits of the clock tick)
1568 	 */
1569 	vdc->session_id = ((uint32_t)gettick() & 0xffffffff);
1570 	DMSG(vdc, 0, "[%d] Set SID to 0x%lx\n", vdc->instance, vdc->session_id);
1571 
1572 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1573 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1574 	pkt.tag.vio_subtype_env = VIO_VER_INFO;
1575 	pkt.tag.vio_sid = vdc->session_id;
1576 	pkt.dev_class = VDEV_DISK;
1577 	pkt.ver_major = ver.major;
1578 	pkt.ver_minor = ver.minor;
1579 
1580 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1581 	DMSG(vdc, 0, "[%d] Ver info sent (status = %d)\n",
1582 	    vdc->instance, status);
1583 	if ((status != 0) || (msglen != sizeof (vio_ver_msg_t))) {
1584 		DMSG(vdc, 0, "[%d] Failed to send Ver negotiation info: "
1585 		    "id(%lx) rv(%d) size(%ld)", vdc->instance,
1586 		    vdc->curr_server->ldc_handle, status, msglen);
1587 		if (msglen != sizeof (vio_ver_msg_t))
1588 			status = ENOMSG;
1589 	}
1590 
1591 	return (status);
1592 }
1593 
1594 /*
1595  * Function:
1596  *	vdc_ver_negotiation()
1597  *
1598  * Description:
1599  *
1600  * Arguments:
1601  *	vdcp	- soft state pointer for this instance of the device driver.
1602  *
1603  * Return Code:
1604  *	0	- Success
1605  */
1606 static int
1607 vdc_ver_negotiation(vdc_t *vdcp)
1608 {
1609 	vio_msg_t vio_msg;
1610 	int status;
1611 
1612 	if (status = vdc_init_ver_negotiation(vdcp, vdc_version[0]))
1613 		return (status);
1614 
1615 	/* release lock and wait for response */
1616 	mutex_exit(&vdcp->lock);
1617 	status = vdc_wait_for_response(vdcp, &vio_msg);
1618 	mutex_enter(&vdcp->lock);
1619 	if (status) {
1620 		DMSG(vdcp, 0,
1621 		    "[%d] Failed waiting for Ver negotiation response, rv(%d)",
1622 		    vdcp->instance, status);
1623 		return (status);
1624 	}
1625 
1626 	/* check type and sub_type ... */
1627 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1628 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1629 		DMSG(vdcp, 0, "[%d] Invalid ver negotiation response\n",
1630 		    vdcp->instance);
1631 		return (EPROTO);
1632 	}
1633 
1634 	return (vdc_handle_ver_msg(vdcp, (vio_ver_msg_t *)&vio_msg));
1635 }
1636 
1637 /*
1638  * Function:
1639  *	vdc_init_attr_negotiation()
1640  *
1641  * Description:
1642  *
1643  * Arguments:
1644  *	vdc	- soft state pointer for this instance of the device driver.
1645  *
1646  * Return Code:
1647  *	0	- Success
1648  */
1649 static int
1650 vdc_init_attr_negotiation(vdc_t *vdc)
1651 {
1652 	vd_attr_msg_t	pkt;
1653 	size_t		msglen = sizeof (pkt);
1654 	int		status;
1655 
1656 	ASSERT(vdc != NULL);
1657 	ASSERT(mutex_owned(&vdc->lock));
1658 
1659 	DMSG(vdc, 0, "[%d] entered\n", vdc->instance);
1660 
1661 	/* fill in tag */
1662 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1663 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1664 	pkt.tag.vio_subtype_env = VIO_ATTR_INFO;
1665 	pkt.tag.vio_sid = vdc->session_id;
1666 	/* fill in payload */
1667 	pkt.max_xfer_sz = vdc->max_xfer_sz;
1668 	pkt.vdisk_block_size = vdc->block_size;
1669 	pkt.xfer_mode = VIO_DRING_MODE_V1_0;
1670 	pkt.operations = 0;	/* server will set bits of valid operations */
1671 	pkt.vdisk_type = 0;	/* server will set to valid device type */
1672 	pkt.vdisk_media = 0;	/* server will set to valid media type */
1673 	pkt.vdisk_size = 0;	/* server will set to valid size */
1674 
1675 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1676 	DMSG(vdc, 0, "Attr info sent (status = %d)\n", status);
1677 
1678 	if ((status != 0) || (msglen != sizeof (vd_attr_msg_t))) {
1679 		DMSG(vdc, 0, "[%d] Failed to send Attr negotiation info: "
1680 		    "id(%lx) rv(%d) size(%ld)", vdc->instance,
1681 		    vdc->curr_server->ldc_handle, status, msglen);
1682 		if (msglen != sizeof (vd_attr_msg_t))
1683 			status = ENOMSG;
1684 	}
1685 
1686 	return (status);
1687 }
1688 
1689 /*
1690  * Function:
1691  *	vdc_attr_negotiation()
1692  *
1693  * Description:
1694  *
1695  * Arguments:
1696  *	vdc	- soft state pointer for this instance of the device driver.
1697  *
1698  * Return Code:
1699  *	0	- Success
1700  */
1701 static int
1702 vdc_attr_negotiation(vdc_t *vdcp)
1703 {
1704 	int status;
1705 	vio_msg_t vio_msg;
1706 
1707 	if (status = vdc_init_attr_negotiation(vdcp))
1708 		return (status);
1709 
1710 	/* release lock and wait for response */
1711 	mutex_exit(&vdcp->lock);
1712 	status = vdc_wait_for_response(vdcp, &vio_msg);
1713 	mutex_enter(&vdcp->lock);
1714 	if (status) {
1715 		DMSG(vdcp, 0,
1716 		    "[%d] Failed waiting for Attr negotiation response, rv(%d)",
1717 		    vdcp->instance, status);
1718 		return (status);
1719 	}
1720 
1721 	/* check type and sub_type ... */
1722 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1723 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1724 		DMSG(vdcp, 0, "[%d] Invalid attr negotiation response\n",
1725 		    vdcp->instance);
1726 		return (EPROTO);
1727 	}
1728 
1729 	return (vdc_handle_attr_msg(vdcp, (vd_attr_msg_t *)&vio_msg));
1730 }
1731 
1732 
1733 /*
1734  * Function:
1735  *	vdc_init_dring_negotiate()
1736  *
1737  * Description:
1738  *
1739  * Arguments:
1740  *	vdc	- soft state pointer for this instance of the device driver.
1741  *
1742  * Return Code:
1743  *	0	- Success
1744  */
1745 static int
1746 vdc_init_dring_negotiate(vdc_t *vdc)
1747 {
1748 	vio_dring_reg_msg_t	pkt;
1749 	size_t			msglen = sizeof (pkt);
1750 	int			status = -1;
1751 	int			retry;
1752 	int			nretries = 10;
1753 
1754 	ASSERT(vdc != NULL);
1755 	ASSERT(mutex_owned(&vdc->lock));
1756 
1757 	for (retry = 0; retry < nretries; retry++) {
1758 		status = vdc_init_descriptor_ring(vdc);
1759 		if (status != EAGAIN)
1760 			break;
1761 		drv_usecwait(vdc_min_timeout_ldc);
1762 	}
1763 
1764 	if (status != 0) {
1765 		DMSG(vdc, 0, "[%d] Failed to init DRing (status = %d)\n",
1766 		    vdc->instance, status);
1767 		return (status);
1768 	}
1769 
1770 	DMSG(vdc, 0, "[%d] Init of descriptor ring completed (status = %d)\n",
1771 	    vdc->instance, status);
1772 
1773 	/* fill in tag */
1774 	pkt.tag.vio_msgtype = VIO_TYPE_CTRL;
1775 	pkt.tag.vio_subtype = VIO_SUBTYPE_INFO;
1776 	pkt.tag.vio_subtype_env = VIO_DRING_REG;
1777 	pkt.tag.vio_sid = vdc->session_id;
1778 	/* fill in payload */
1779 	pkt.dring_ident = 0;
1780 	pkt.num_descriptors = vdc->dring_len;
1781 	pkt.descriptor_size = vdc->dring_entry_size;
1782 	pkt.options = (VIO_TX_DRING | VIO_RX_DRING);
1783 	pkt.ncookies = vdc->dring_cookie_count;
1784 	pkt.cookie[0] = vdc->dring_cookie[0];	/* for now just one cookie */
1785 
1786 	status = vdc_send(vdc, (caddr_t)&pkt, &msglen);
1787 	if (status != 0) {
1788 		DMSG(vdc, 0, "[%d] Failed to register DRing (err = %d)",
1789 		    vdc->instance, status);
1790 	}
1791 
1792 	return (status);
1793 }
1794 
1795 
1796 /*
1797  * Function:
1798  *	vdc_dring_negotiation()
1799  *
1800  * Description:
1801  *
1802  * Arguments:
1803  *	vdc	- soft state pointer for this instance of the device driver.
1804  *
1805  * Return Code:
1806  *	0	- Success
1807  */
1808 static int
1809 vdc_dring_negotiation(vdc_t *vdcp)
1810 {
1811 	int status;
1812 	vio_msg_t vio_msg;
1813 
1814 	if (status = vdc_init_dring_negotiate(vdcp))
1815 		return (status);
1816 
1817 	/* release lock and wait for response */
1818 	mutex_exit(&vdcp->lock);
1819 	status = vdc_wait_for_response(vdcp, &vio_msg);
1820 	mutex_enter(&vdcp->lock);
1821 	if (status) {
1822 		DMSG(vdcp, 0,
1823 		    "[%d] Failed waiting for Dring negotiation response,"
1824 		    " rv(%d)", vdcp->instance, status);
1825 		return (status);
1826 	}
1827 
1828 	/* check type and sub_type ... */
1829 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1830 	    vio_msg.tag.vio_subtype == VIO_SUBTYPE_INFO) {
1831 		DMSG(vdcp, 0, "[%d] Invalid Dring negotiation response\n",
1832 		    vdcp->instance);
1833 		return (EPROTO);
1834 	}
1835 
1836 	return (vdc_handle_dring_reg_msg(vdcp,
1837 	    (vio_dring_reg_msg_t *)&vio_msg));
1838 }
1839 
1840 
1841 /*
1842  * Function:
1843  *	vdc_send_rdx()
1844  *
1845  * Description:
1846  *
1847  * Arguments:
1848  *	vdc	- soft state pointer for this instance of the device driver.
1849  *
1850  * Return Code:
1851  *	0	- Success
1852  */
1853 static int
1854 vdc_send_rdx(vdc_t *vdcp)
1855 {
1856 	vio_msg_t	msg;
1857 	size_t		msglen = sizeof (vio_msg_t);
1858 	int		status;
1859 
1860 	/*
1861 	 * Send an RDX message to vds to indicate we are ready
1862 	 * to send data
1863 	 */
1864 	msg.tag.vio_msgtype = VIO_TYPE_CTRL;
1865 	msg.tag.vio_subtype = VIO_SUBTYPE_INFO;
1866 	msg.tag.vio_subtype_env = VIO_RDX;
1867 	msg.tag.vio_sid = vdcp->session_id;
1868 	status = vdc_send(vdcp, (caddr_t)&msg, &msglen);
1869 	if (status != 0) {
1870 		DMSG(vdcp, 0, "[%d] Failed to send RDX message (%d)",
1871 		    vdcp->instance, status);
1872 	}
1873 
1874 	return (status);
1875 }
1876 
1877 /*
1878  * Function:
1879  *	vdc_handle_rdx()
1880  *
1881  * Description:
1882  *
1883  * Arguments:
1884  *	vdc	- soft state pointer for this instance of the device driver.
1885  *	msgp	- received msg
1886  *
1887  * Return Code:
1888  *	0	- Success
1889  */
1890 static int
1891 vdc_handle_rdx(vdc_t *vdcp, vio_rdx_msg_t *msgp)
1892 {
1893 	_NOTE(ARGUNUSED(vdcp))
1894 	_NOTE(ARGUNUSED(msgp))
1895 
1896 	ASSERT(msgp->tag.vio_msgtype == VIO_TYPE_CTRL);
1897 	ASSERT(msgp->tag.vio_subtype == VIO_SUBTYPE_ACK);
1898 	ASSERT(msgp->tag.vio_subtype_env == VIO_RDX);
1899 
1900 	DMSG(vdcp, 1, "[%d] Got an RDX msg", vdcp->instance);
1901 
1902 	return (0);
1903 }
1904 
1905 /*
1906  * Function:
1907  *	vdc_rdx_exchange()
1908  *
1909  * Description:
1910  *
1911  * Arguments:
1912  *	vdc	- soft state pointer for this instance of the device driver.
1913  *
1914  * Return Code:
1915  *	0	- Success
1916  */
1917 static int
1918 vdc_rdx_exchange(vdc_t *vdcp)
1919 {
1920 	int status;
1921 	vio_msg_t vio_msg;
1922 
1923 	if (status = vdc_send_rdx(vdcp))
1924 		return (status);
1925 
1926 	/* release lock and wait for response */
1927 	mutex_exit(&vdcp->lock);
1928 	status = vdc_wait_for_response(vdcp, &vio_msg);
1929 	mutex_enter(&vdcp->lock);
1930 	if (status) {
1931 		DMSG(vdcp, 0, "[%d] Failed waiting for RDX response, rv(%d)",
1932 		    vdcp->instance, status);
1933 		return (status);
1934 	}
1935 
1936 	/* check type and sub_type ... */
1937 	if (vio_msg.tag.vio_msgtype != VIO_TYPE_CTRL ||
1938 	    vio_msg.tag.vio_subtype != VIO_SUBTYPE_ACK) {
1939 		DMSG(vdcp, 0, "[%d] Invalid RDX response\n", vdcp->instance);
1940 		return (EPROTO);
1941 	}
1942 
1943 	return (vdc_handle_rdx(vdcp, (vio_rdx_msg_t *)&vio_msg));
1944 }
1945 
1946 
1947 /* -------------------------------------------------------------------------- */
1948 
1949 /*
1950  * LDC helper routines
1951  */
1952 
1953 static int
1954 vdc_recv(vdc_t *vdc, vio_msg_t *msgp, size_t *nbytesp)
1955 {
1956 	int		status;
1957 	boolean_t	q_has_pkts = B_FALSE;
1958 	uint64_t	delay_time;
1959 	size_t		len;
1960 
1961 	mutex_enter(&vdc->read_lock);
1962 
1963 	if (vdc->read_state == VDC_READ_IDLE)
1964 		vdc->read_state = VDC_READ_WAITING;
1965 
1966 	while (vdc->read_state != VDC_READ_PENDING) {
1967 
1968 		/* detect if the connection has been reset */
1969 		if (vdc->read_state == VDC_READ_RESET) {
1970 			status = ECONNRESET;
1971 			goto done;
1972 		}
1973 
1974 		cv_wait(&vdc->read_cv, &vdc->read_lock);
1975 	}
1976 
1977 	/*
1978 	 * Until we get a blocking ldc read we have to retry
1979 	 * until the entire LDC message has arrived before
1980 	 * ldc_read() will succeed. Note we also bail out if
1981 	 * the channel is reset or goes away.
1982 	 */
1983 	delay_time = vdc_ldc_read_init_delay;
1984 loop:
1985 	len = *nbytesp;
1986 	status = ldc_read(vdc->curr_server->ldc_handle, (caddr_t)msgp, &len);
1987 	switch (status) {
1988 	case EAGAIN:
1989 		delay_time *= 2;
1990 		if (delay_time >= vdc_ldc_read_max_delay)
1991 			delay_time = vdc_ldc_read_max_delay;
1992 		delay(delay_time);
1993 		goto loop;
1994 
1995 	case 0:
1996 		if (len == 0) {
1997 			DMSG(vdc, 1, "[%d] ldc_read returned 0 bytes with "
1998 			    "no error!\n", vdc->instance);
1999 			goto loop;
2000 		}
2001 
2002 		*nbytesp = len;
2003 
2004 		/*
2005 		 * If there are pending messages, leave the
2006 		 * read state as pending. Otherwise, set the state
2007 		 * back to idle.
2008 		 */
2009 		status = ldc_chkq(vdc->curr_server->ldc_handle, &q_has_pkts);
2010 		if (status == 0 && !q_has_pkts)
2011 			vdc->read_state = VDC_READ_IDLE;
2012 
2013 		break;
2014 	default:
2015 		DMSG(vdc, 0, "ldc_read returned %d\n", status);
2016 		break;
2017 	}
2018 
2019 done:
2020 	mutex_exit(&vdc->read_lock);
2021 
2022 	return (status);
2023 }
2024 
2025 
2026 
2027 #ifdef DEBUG
2028 void
2029 vdc_decode_tag(vdc_t *vdcp, vio_msg_t *msg)
2030 {
2031 	char *ms, *ss, *ses;
2032 	switch (msg->tag.vio_msgtype) {
2033 #define	Q(_s)	case _s : ms = #_s; break;
2034 	Q(VIO_TYPE_CTRL)
2035 	Q(VIO_TYPE_DATA)
2036 	Q(VIO_TYPE_ERR)
2037 #undef Q
2038 	default: ms = "unknown"; break;
2039 	}
2040 
2041 	switch (msg->tag.vio_subtype) {
2042 #define	Q(_s)	case _s : ss = #_s; break;
2043 	Q(VIO_SUBTYPE_INFO)
2044 	Q(VIO_SUBTYPE_ACK)
2045 	Q(VIO_SUBTYPE_NACK)
2046 #undef Q
2047 	default: ss = "unknown"; break;
2048 	}
2049 
2050 	switch (msg->tag.vio_subtype_env) {
2051 #define	Q(_s)	case _s : ses = #_s; break;
2052 	Q(VIO_VER_INFO)
2053 	Q(VIO_ATTR_INFO)
2054 	Q(VIO_DRING_REG)
2055 	Q(VIO_DRING_UNREG)
2056 	Q(VIO_RDX)
2057 	Q(VIO_PKT_DATA)
2058 	Q(VIO_DESC_DATA)
2059 	Q(VIO_DRING_DATA)
2060 #undef Q
2061 	default: ses = "unknown"; break;
2062 	}
2063 
2064 	DMSG(vdcp, 3, "(%x/%x/%x) message : (%s/%s/%s)\n",
2065 	    msg->tag.vio_msgtype, msg->tag.vio_subtype,
2066 	    msg->tag.vio_subtype_env, ms, ss, ses);
2067 }
2068 #endif
2069 
2070 /*
2071  * Function:
2072  *	vdc_send()
2073  *
2074  * Description:
2075  *	The function encapsulates the call to write a message using LDC.
2076  *	If LDC indicates that the call failed due to the queue being full,
2077  *	we retry the ldc_write(), otherwise we return the error returned by LDC.
2078  *
2079  * Arguments:
2080  *	ldc_handle	- LDC handle for the channel this instance of vdc uses
2081  *	pkt		- address of LDC message to be sent
2082  *	msglen		- the size of the message being sent. When the function
2083  *			  returns, this contains the number of bytes written.
2084  *
2085  * Return Code:
2086  *	0		- Success.
2087  *	EINVAL		- pkt or msglen were NULL
2088  *	ECONNRESET	- The connection was not up.
2089  *	EWOULDBLOCK	- LDC queue is full
2090  *	xxx		- other error codes returned by ldc_write
2091  */
2092 static int
2093 vdc_send(vdc_t *vdc, caddr_t pkt, size_t *msglen)
2094 {
2095 	size_t	size = 0;
2096 	int	status = 0;
2097 	clock_t delay_ticks;
2098 
2099 	ASSERT(vdc != NULL);
2100 	ASSERT(mutex_owned(&vdc->lock));
2101 	ASSERT(msglen != NULL);
2102 	ASSERT(*msglen != 0);
2103 
2104 #ifdef DEBUG
2105 	vdc_decode_tag(vdc, (vio_msg_t *)(uintptr_t)pkt);
2106 #endif
2107 	/*
2108 	 * Wait indefinitely to send if channel
2109 	 * is busy, but bail out if we succeed or
2110 	 * if the channel closes or is reset.
2111 	 */
2112 	delay_ticks = vdc_hz_min_ldc_delay;
2113 	do {
2114 		size = *msglen;
2115 		status = ldc_write(vdc->curr_server->ldc_handle, pkt, &size);
2116 		if (status == EWOULDBLOCK) {
2117 			delay(delay_ticks);
2118 			/* geometric backoff */
2119 			delay_ticks *= 2;
2120 			if (delay_ticks > vdc_hz_max_ldc_delay)
2121 				delay_ticks = vdc_hz_max_ldc_delay;
2122 		}
2123 	} while (status == EWOULDBLOCK);
2124 
2125 	/* if LDC had serious issues --- reset vdc state */
2126 	if (status == EIO || status == ECONNRESET) {
2127 		/* LDC had serious issues --- reset vdc state */
2128 		mutex_enter(&vdc->read_lock);
2129 		if ((vdc->read_state == VDC_READ_WAITING) ||
2130 		    (vdc->read_state == VDC_READ_RESET))
2131 			cv_signal(&vdc->read_cv);
2132 		vdc->read_state = VDC_READ_RESET;
2133 		mutex_exit(&vdc->read_lock);
2134 
2135 		/* wake up any waiters in the reset thread */
2136 		if (vdc->state == VDC_STATE_INIT_WAITING) {
2137 			DMSG(vdc, 0, "[%d] write reset - "
2138 			    "vdc is resetting ..\n", vdc->instance);
2139 			vdc->state = VDC_STATE_RESETTING;
2140 			cv_signal(&vdc->initwait_cv);
2141 		}
2142 
2143 		return (ECONNRESET);
2144 	}
2145 
2146 	/* return the last size written */
2147 	*msglen = size;
2148 
2149 	return (status);
2150 }
2151 
2152 /*
2153  * Function:
2154  *	vdc_get_md_node
2155  *
2156  * Description:
2157  *	Get the MD, the device node for the given disk instance. The
2158  *	caller is responsible for cleaning up the reference to the
2159  *	returned MD (mdpp) by calling md_fini_handle().
2160  *
2161  * Arguments:
2162  *	dip	- dev info pointer for this instance of the device driver.
2163  *	mdpp	- the returned MD.
2164  *	vd_nodep - the returned device node.
2165  *
2166  * Return Code:
2167  *	0	- Success.
2168  *	ENOENT	- Expected node or property did not exist.
2169  *	ENXIO	- Unexpected error communicating with MD framework
2170  */
2171 static int
2172 vdc_get_md_node(dev_info_t *dip, md_t **mdpp, mde_cookie_t *vd_nodep)
2173 {
2174 	int		status = ENOENT;
2175 	char		*node_name = NULL;
2176 	md_t		*mdp = NULL;
2177 	int		num_nodes;
2178 	int		num_vdevs;
2179 	mde_cookie_t	rootnode;
2180 	mde_cookie_t	*listp = NULL;
2181 	boolean_t	found_inst = B_FALSE;
2182 	int		listsz;
2183 	int		idx;
2184 	uint64_t	md_inst;
2185 	int		obp_inst;
2186 	int		instance = ddi_get_instance(dip);
2187 
2188 	/*
2189 	 * Get the OBP instance number for comparison with the MD instance
2190 	 *
2191 	 * The "cfg-handle" property of a vdc node in an MD contains the MD's
2192 	 * notion of "instance", or unique identifier, for that node; OBP
2193 	 * stores the value of the "cfg-handle" MD property as the value of
2194 	 * the "reg" property on the node in the device tree it builds from
2195 	 * the MD and passes to Solaris.  Thus, we look up the devinfo node's
2196 	 * "reg" property value to uniquely identify this device instance.
2197 	 * If the "reg" property cannot be found, the device tree state is
2198 	 * presumably so broken that there is no point in continuing.
2199 	 */
2200 	if (!ddi_prop_exists(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS, OBP_REG)) {
2201 		cmn_err(CE_WARN, "'%s' property does not exist", OBP_REG);
2202 		return (ENOENT);
2203 	}
2204 	obp_inst = ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
2205 	    OBP_REG, -1);
2206 	DMSGX(1, "[%d] OBP inst=%d\n", instance, obp_inst);
2207 
2208 	/*
2209 	 * We now walk the MD nodes to find the node for this vdisk.
2210 	 */
2211 	if ((mdp = md_get_handle()) == NULL) {
2212 		cmn_err(CE_WARN, "unable to init machine description");
2213 		return (ENXIO);
2214 	}
2215 
2216 	num_nodes = md_node_count(mdp);
2217 	ASSERT(num_nodes > 0);
2218 
2219 	listsz = num_nodes * sizeof (mde_cookie_t);
2220 
2221 	/* allocate memory for nodes */
2222 	listp = kmem_zalloc(listsz, KM_SLEEP);
2223 
2224 	rootnode = md_root_node(mdp);
2225 	ASSERT(rootnode != MDE_INVAL_ELEM_COOKIE);
2226 
2227 	/*
2228 	 * Search for all the virtual devices, we will then check to see which
2229 	 * ones are disk nodes.
2230 	 */
2231 	num_vdevs = md_scan_dag(mdp, rootnode,
2232 	    md_find_name(mdp, VDC_MD_VDEV_NAME),
2233 	    md_find_name(mdp, "fwd"), listp);
2234 
2235 	if (num_vdevs <= 0) {
2236 		cmn_err(CE_NOTE, "No '%s' node found", VDC_MD_VDEV_NAME);
2237 		status = ENOENT;
2238 		goto done;
2239 	}
2240 
2241 	DMSGX(1, "[%d] num_vdevs=%d\n", instance, num_vdevs);
2242 	for (idx = 0; idx < num_vdevs; idx++) {
2243 		status = md_get_prop_str(mdp, listp[idx], "name", &node_name);
2244 		if ((status != 0) || (node_name == NULL)) {
2245 			cmn_err(CE_NOTE, "Unable to get name of node type '%s'"
2246 			    ": err %d", VDC_MD_VDEV_NAME, status);
2247 			continue;
2248 		}
2249 
2250 		DMSGX(1, "[%d] Found node '%s'\n", instance, node_name);
2251 		if (strcmp(VDC_MD_DISK_NAME, node_name) == 0) {
2252 			status = md_get_prop_val(mdp, listp[idx],
2253 			    VDC_MD_CFG_HDL, &md_inst);
2254 			DMSGX(1, "[%d] vdc inst in MD=%lx\n",
2255 			    instance, md_inst);
2256 			if ((status == 0) && (md_inst == obp_inst)) {
2257 				found_inst = B_TRUE;
2258 				break;
2259 			}
2260 		}
2261 	}
2262 
2263 	if (!found_inst) {
2264 		DMSGX(0, "Unable to find correct '%s' node", VDC_MD_DISK_NAME);
2265 		status = ENOENT;
2266 		goto done;
2267 	}
2268 	DMSGX(0, "[%d] MD inst=%lx\n", instance, md_inst);
2269 
2270 	*vd_nodep = listp[idx];
2271 	*mdpp = mdp;
2272 done:
2273 	kmem_free(listp, listsz);
2274 	return (status);
2275 }
2276 
2277 /*
2278  * Function:
2279  *	vdc_init_ports
2280  *
2281  * Description:
2282  *	Initialize all the ports for this vdisk instance.
2283  *
2284  * Arguments:
2285  *	vdc	- soft state pointer for this instance of the device driver.
2286  *	mdp	- md pointer
2287  *	vd_nodep - device md node.
2288  *
2289  * Return Code:
2290  *	0	- Success.
2291  *	ENOENT	- Expected node or property did not exist.
2292  */
2293 static int
2294 vdc_init_ports(vdc_t *vdc, md_t *mdp, mde_cookie_t vd_nodep)
2295 {
2296 	int		status = 0;
2297 	int		idx;
2298 	int		num_nodes;
2299 	int		num_vports;
2300 	int		num_chans;
2301 	int		listsz;
2302 	mde_cookie_t	vd_port;
2303 	mde_cookie_t	*chanp = NULL;
2304 	mde_cookie_t	*portp = NULL;
2305 	vdc_server_t	*srvr;
2306 	vdc_server_t	*prev_srvr = NULL;
2307 
2308 	/*
2309 	 * We now walk the MD nodes to find the port nodes for this vdisk.
2310 	 */
2311 	num_nodes = md_node_count(mdp);
2312 	ASSERT(num_nodes > 0);
2313 
2314 	listsz = num_nodes * sizeof (mde_cookie_t);
2315 
2316 	/* allocate memory for nodes */
2317 	portp = kmem_zalloc(listsz, KM_SLEEP);
2318 	chanp = kmem_zalloc(listsz, KM_SLEEP);
2319 
2320 	num_vports = md_scan_dag(mdp, vd_nodep,
2321 	    md_find_name(mdp, VDC_MD_PORT_NAME),
2322 	    md_find_name(mdp, "fwd"), portp);
2323 	if (num_vports == 0) {
2324 		DMSGX(0, "Found no '%s' node for '%s' port\n",
2325 		    VDC_MD_PORT_NAME, VDC_MD_VDEV_NAME);
2326 		status = ENOENT;
2327 		goto done;
2328 	}
2329 
2330 	DMSGX(1, "Found %d '%s' node(s) for '%s' port\n",
2331 	    num_vports, VDC_MD_PORT_NAME, VDC_MD_VDEV_NAME);
2332 
2333 	vdc->num_servers = 0;
2334 	for (idx = 0; idx < num_vports; idx++) {
2335 
2336 		/* initialize this port */
2337 		vd_port = portp[idx];
2338 		srvr = kmem_zalloc(sizeof (vdc_server_t), KM_SLEEP);
2339 		srvr->vdcp = vdc;
2340 
2341 		/* get port id */
2342 		if (md_get_prop_val(mdp, vd_port, VDC_MD_ID, &srvr->id) != 0) {
2343 			cmn_err(CE_NOTE, "vDisk port '%s' property not found",
2344 			    VDC_MD_ID);
2345 			kmem_free(srvr, sizeof (vdc_server_t));
2346 			continue;
2347 		}
2348 
2349 		/* set the connection timeout */
2350 		if (md_get_prop_val(mdp, vd_port, VDC_MD_TIMEOUT,
2351 		    &srvr->ctimeout) != 0) {
2352 			srvr->ctimeout = 0;
2353 		}
2354 
2355 		/* get the ldc id */
2356 		num_chans = md_scan_dag(mdp, vd_port,
2357 		    md_find_name(mdp, VDC_MD_CHAN_NAME),
2358 		    md_find_name(mdp, "fwd"), chanp);
2359 
2360 		/* expecting at least one channel */
2361 		if (num_chans <= 0) {
2362 			cmn_err(CE_NOTE, "No '%s' node for '%s' port",
2363 			    VDC_MD_CHAN_NAME, VDC_MD_VDEV_NAME);
2364 			kmem_free(srvr, sizeof (vdc_server_t));
2365 			continue;
2366 		} else if (num_chans != 1) {
2367 			DMSGX(0, "Expected 1 '%s' node for '%s' port, "
2368 			    "found %d\n", VDC_MD_CHAN_NAME, VDC_MD_VDEV_NAME,
2369 			    num_chans);
2370 		}
2371 
2372 		/*
2373 		 * We use the first channel found (index 0), irrespective of how
2374 		 * many are there in total.
2375 		 */
2376 		if (md_get_prop_val(mdp, chanp[0], VDC_MD_ID,
2377 		    &srvr->ldc_id) != 0) {
2378 			cmn_err(CE_NOTE, "Channel '%s' property not found",
2379 			    VDC_MD_ID);
2380 			kmem_free(srvr, sizeof (vdc_server_t));
2381 			continue;
2382 		}
2383 
2384 		/*
2385 		 * now initialise LDC channel which will be used to
2386 		 * communicate with this server
2387 		 */
2388 		if (vdc_do_ldc_init(vdc, srvr) != 0) {
2389 			kmem_free(srvr, sizeof (vdc_server_t));
2390 			continue;
2391 		}
2392 
2393 		/* add server to list */
2394 		if (prev_srvr)
2395 			prev_srvr->next = srvr;
2396 		else
2397 			vdc->server_list = srvr;
2398 
2399 		prev_srvr = srvr;
2400 
2401 		/* inc numbers of servers */
2402 		vdc->num_servers++;
2403 	}
2404 
2405 	/*
2406 	 * Adjust the max number of handshake retries to match
2407 	 * the number of vdisk servers.
2408 	 */
2409 	if (vdc_hshake_retries < vdc->num_servers)
2410 		vdc_hshake_retries = vdc->num_servers;
2411 
2412 	/* pick first server as current server */
2413 	if (vdc->server_list != NULL) {
2414 		vdc->curr_server = vdc->server_list;
2415 		status = 0;
2416 	} else {
2417 		status = ENOENT;
2418 	}
2419 
2420 done:
2421 	kmem_free(chanp, listsz);
2422 	kmem_free(portp, listsz);
2423 	return (status);
2424 }
2425 
2426 
2427 /*
2428  * Function:
2429  *	vdc_do_ldc_up
2430  *
2431  * Description:
2432  *	Bring the channel for the current server up.
2433  *
2434  * Arguments:
2435  *	vdc	- soft state pointer for this instance of the device driver.
2436  *
2437  * Return Code:
2438  *	0		- Success.
2439  *	EINVAL		- Driver is detaching / LDC error
2440  *	ECONNREFUSED	- Other end is not listening
2441  */
2442 static int
2443 vdc_do_ldc_up(vdc_t *vdc)
2444 {
2445 	int		status;
2446 	ldc_status_t	ldc_state;
2447 
2448 	ASSERT(MUTEX_HELD(&vdc->lock));
2449 
2450 	DMSG(vdc, 0, "[%d] Bringing up channel %lx\n",
2451 	    vdc->instance, vdc->curr_server->ldc_id);
2452 
2453 	if (vdc->lifecycle == VDC_LC_DETACHING)
2454 		return (EINVAL);
2455 
2456 	if ((status = ldc_up(vdc->curr_server->ldc_handle)) != 0) {
2457 		switch (status) {
2458 		case ECONNREFUSED:	/* listener not ready at other end */
2459 			DMSG(vdc, 0, "[%d] ldc_up(%lx,...) return %d\n",
2460 			    vdc->instance, vdc->curr_server->ldc_id, status);
2461 			status = 0;
2462 			break;
2463 		default:
2464 			DMSG(vdc, 0, "[%d] Failed to bring up LDC: "
2465 			    "channel=%ld, err=%d", vdc->instance,
2466 			    vdc->curr_server->ldc_id, status);
2467 			break;
2468 		}
2469 	}
2470 
2471 	if (ldc_status(vdc->curr_server->ldc_handle, &ldc_state) == 0) {
2472 		vdc->curr_server->ldc_state = ldc_state;
2473 		if (ldc_state == LDC_UP) {
2474 			DMSG(vdc, 0, "[%d] LDC channel already up\n",
2475 			    vdc->instance);
2476 			vdc->seq_num = 1;
2477 			vdc->seq_num_reply = 0;
2478 		}
2479 	}
2480 
2481 	return (status);
2482 }
2483 
2484 /*
2485  * Function:
2486  *	vdc_terminate_ldc()
2487  *
2488  * Description:
2489  *
2490  * Arguments:
2491  *	vdc	- soft state pointer for this instance of the device driver.
2492  *	srvr	- vdc per-server info structure
2493  *
2494  * Return Code:
2495  *	None
2496  */
2497 static void
2498 vdc_terminate_ldc(vdc_t *vdc, vdc_server_t *srvr)
2499 {
2500 	int	instance = ddi_get_instance(vdc->dip);
2501 
2502 	if (srvr->state & VDC_LDC_OPEN) {
2503 		DMSG(vdc, 0, "[%d] ldc_close()\n", instance);
2504 		(void) ldc_close(srvr->ldc_handle);
2505 	}
2506 	if (srvr->state & VDC_LDC_CB) {
2507 		DMSG(vdc, 0, "[%d] ldc_unreg_callback()\n", instance);
2508 		(void) ldc_unreg_callback(srvr->ldc_handle);
2509 	}
2510 	if (srvr->state & VDC_LDC_INIT) {
2511 		DMSG(vdc, 0, "[%d] ldc_fini()\n", instance);
2512 		(void) ldc_fini(srvr->ldc_handle);
2513 		srvr->ldc_handle = NULL;
2514 	}
2515 
2516 	srvr->state &= ~(VDC_LDC_INIT | VDC_LDC_CB | VDC_LDC_OPEN);
2517 }
2518 
2519 /*
2520  * Function:
2521  *	vdc_fini_ports()
2522  *
2523  * Description:
2524  *	Finalize all ports by closing the channel associated with each
2525  *	port and also freeing the server structure.
2526  *
2527  * Arguments:
2528  *	vdc	- soft state pointer for this instance of the device driver.
2529  *
2530  * Return Code:
2531  *	None
2532  */
2533 static void
2534 vdc_fini_ports(vdc_t *vdc)
2535 {
2536 	int		instance = ddi_get_instance(vdc->dip);
2537 	vdc_server_t	*srvr, *prev_srvr;
2538 
2539 	ASSERT(vdc != NULL);
2540 	ASSERT(mutex_owned(&vdc->lock));
2541 
2542 	DMSG(vdc, 0, "[%d] initialized=%x\n", instance, vdc->initialized);
2543 
2544 	srvr = vdc->server_list;
2545 
2546 	while (srvr) {
2547 
2548 		vdc_terminate_ldc(vdc, srvr);
2549 
2550 		/* next server */
2551 		prev_srvr = srvr;
2552 		srvr = srvr->next;
2553 
2554 		/* free server */
2555 		kmem_free(prev_srvr, sizeof (vdc_server_t));
2556 	}
2557 
2558 	vdc->server_list = NULL;
2559 }
2560 
2561 /* -------------------------------------------------------------------------- */
2562 
2563 /*
2564  * Descriptor Ring helper routines
2565  */
2566 
2567 /*
2568  * Function:
2569  *	vdc_init_descriptor_ring()
2570  *
2571  * Description:
2572  *
2573  * Arguments:
2574  *	vdc	- soft state pointer for this instance of the device driver.
2575  *
2576  * Return Code:
2577  *	0	- Success
2578  */
2579 static int
2580 vdc_init_descriptor_ring(vdc_t *vdc)
2581 {
2582 	vd_dring_entry_t	*dep = NULL;	/* DRing Entry pointer */
2583 	int	status = 0;
2584 	int	i;
2585 
2586 	DMSG(vdc, 0, "[%d] initialized=%x\n", vdc->instance, vdc->initialized);
2587 
2588 	ASSERT(vdc != NULL);
2589 	ASSERT(mutex_owned(&vdc->lock));
2590 
2591 	/* ensure we have enough room to store max sized block */
2592 	ASSERT(maxphys <= VD_MAX_BLOCK_SIZE);
2593 
2594 	if ((vdc->initialized & VDC_DRING_INIT) == 0) {
2595 		DMSG(vdc, 0, "[%d] ldc_mem_dring_create\n", vdc->instance);
2596 		/*
2597 		 * Calculate the maximum block size we can transmit using one
2598 		 * Descriptor Ring entry from the attributes returned by the
2599 		 * vDisk server. This is subject to a minimum of 'maxphys'
2600 		 * as we do not have the capability to split requests over
2601 		 * multiple DRing entries.
2602 		 */
2603 		if ((vdc->max_xfer_sz * vdc->block_size) < maxphys) {
2604 			DMSG(vdc, 0, "[%d] using minimum DRing size\n",
2605 			    vdc->instance);
2606 			vdc->dring_max_cookies = maxphys / PAGESIZE;
2607 		} else {
2608 			vdc->dring_max_cookies =
2609 			    (vdc->max_xfer_sz * vdc->block_size) / PAGESIZE;
2610 		}
2611 		vdc->dring_entry_size = (sizeof (vd_dring_entry_t) +
2612 		    (sizeof (ldc_mem_cookie_t) *
2613 		    (vdc->dring_max_cookies - 1)));
2614 		vdc->dring_len = VD_DRING_LEN;
2615 
2616 		status = ldc_mem_dring_create(vdc->dring_len,
2617 		    vdc->dring_entry_size, &vdc->dring_hdl);
2618 		if ((vdc->dring_hdl == NULL) || (status != 0)) {
2619 			DMSG(vdc, 0, "[%d] Descriptor ring creation failed",
2620 			    vdc->instance);
2621 			return (status);
2622 		}
2623 		vdc->initialized |= VDC_DRING_INIT;
2624 	}
2625 
2626 	if ((vdc->initialized & VDC_DRING_BOUND) == 0) {
2627 		DMSG(vdc, 0, "[%d] ldc_mem_dring_bind\n", vdc->instance);
2628 		vdc->dring_cookie =
2629 		    kmem_zalloc(sizeof (ldc_mem_cookie_t), KM_SLEEP);
2630 
2631 		status = ldc_mem_dring_bind(vdc->curr_server->ldc_handle,
2632 		    vdc->dring_hdl,
2633 		    LDC_SHADOW_MAP|LDC_DIRECT_MAP, LDC_MEM_RW,
2634 		    &vdc->dring_cookie[0],
2635 		    &vdc->dring_cookie_count);
2636 		if (status != 0) {
2637 			DMSG(vdc, 0, "[%d] Failed to bind descriptor ring "
2638 			    "(%lx) to channel (%lx) status=%d\n",
2639 			    vdc->instance, vdc->dring_hdl,
2640 			    vdc->curr_server->ldc_handle, status);
2641 			return (status);
2642 		}
2643 		ASSERT(vdc->dring_cookie_count == 1);
2644 		vdc->initialized |= VDC_DRING_BOUND;
2645 	}
2646 
2647 	status = ldc_mem_dring_info(vdc->dring_hdl, &vdc->dring_mem_info);
2648 	if (status != 0) {
2649 		DMSG(vdc, 0,
2650 		    "[%d] Failed to get info for descriptor ring (%lx)\n",
2651 		    vdc->instance, vdc->dring_hdl);
2652 		return (status);
2653 	}
2654 
2655 	if ((vdc->initialized & VDC_DRING_LOCAL) == 0) {
2656 		DMSG(vdc, 0, "[%d] local dring\n", vdc->instance);
2657 
2658 		/* Allocate the local copy of this dring */
2659 		vdc->local_dring =
2660 		    kmem_zalloc(vdc->dring_len * sizeof (vdc_local_desc_t),
2661 		    KM_SLEEP);
2662 		vdc->initialized |= VDC_DRING_LOCAL;
2663 	}
2664 
2665 	/*
2666 	 * Mark all DRing entries as free and initialize the private
2667 	 * descriptor's memory handles. If any entry is initialized,
2668 	 * we need to free it later so we set the bit in 'initialized'
2669 	 * at the start.
2670 	 */
2671 	vdc->initialized |= VDC_DRING_ENTRY;
2672 	for (i = 0; i < vdc->dring_len; i++) {
2673 		dep = VDC_GET_DRING_ENTRY_PTR(vdc, i);
2674 		dep->hdr.dstate = VIO_DESC_FREE;
2675 
2676 		status = ldc_mem_alloc_handle(vdc->curr_server->ldc_handle,
2677 		    &vdc->local_dring[i].desc_mhdl);
2678 		if (status != 0) {
2679 			DMSG(vdc, 0, "![%d] Failed to alloc mem handle for"
2680 			    " descriptor %d", vdc->instance, i);
2681 			return (status);
2682 		}
2683 		vdc->local_dring[i].is_free = B_TRUE;
2684 		vdc->local_dring[i].dep = dep;
2685 	}
2686 
2687 	/* Initialize the starting index */
2688 	vdc->dring_curr_idx = 0;
2689 
2690 	return (status);
2691 }
2692 
2693 /*
2694  * Function:
2695  *	vdc_destroy_descriptor_ring()
2696  *
2697  * Description:
2698  *
2699  * Arguments:
2700  *	vdc	- soft state pointer for this instance of the device driver.
2701  *
2702  * Return Code:
2703  *	None
2704  */
2705 static void
2706 vdc_destroy_descriptor_ring(vdc_t *vdc)
2707 {
2708 	vdc_local_desc_t	*ldep = NULL;	/* Local Dring Entry Pointer */
2709 	ldc_mem_handle_t	mhdl = NULL;
2710 	ldc_mem_info_t		minfo;
2711 	int			status = -1;
2712 	int			i;	/* loop */
2713 
2714 	ASSERT(vdc != NULL);
2715 	ASSERT(mutex_owned(&vdc->lock));
2716 
2717 	DMSG(vdc, 0, "[%d] Entered\n", vdc->instance);
2718 
2719 	if (vdc->initialized & VDC_DRING_ENTRY) {
2720 		DMSG(vdc, 0,
2721 		    "[%d] Removing Local DRing entries\n", vdc->instance);
2722 		for (i = 0; i < vdc->dring_len; i++) {
2723 			ldep = &vdc->local_dring[i];
2724 			mhdl = ldep->desc_mhdl;
2725 
2726 			if (mhdl == NULL)
2727 				continue;
2728 
2729 			if ((status = ldc_mem_info(mhdl, &minfo)) != 0) {
2730 				DMSG(vdc, 0,
2731 				    "ldc_mem_info returned an error: %d\n",
2732 				    status);
2733 
2734 				/*
2735 				 * This must mean that the mem handle
2736 				 * is not valid. Clear it out so that
2737 				 * no one tries to use it.
2738 				 */
2739 				ldep->desc_mhdl = NULL;
2740 				continue;
2741 			}
2742 
2743 			if (minfo.status == LDC_BOUND) {
2744 				(void) ldc_mem_unbind_handle(mhdl);
2745 			}
2746 
2747 			(void) ldc_mem_free_handle(mhdl);
2748 
2749 			ldep->desc_mhdl = NULL;
2750 		}
2751 		vdc->initialized &= ~VDC_DRING_ENTRY;
2752 	}
2753 
2754 	if (vdc->initialized & VDC_DRING_LOCAL) {
2755 		DMSG(vdc, 0, "[%d] Freeing Local DRing\n", vdc->instance);
2756 		kmem_free(vdc->local_dring,
2757 		    vdc->dring_len * sizeof (vdc_local_desc_t));
2758 		vdc->initialized &= ~VDC_DRING_LOCAL;
2759 	}
2760 
2761 	if (vdc->initialized & VDC_DRING_BOUND) {
2762 		DMSG(vdc, 0, "[%d] Unbinding DRing\n", vdc->instance);
2763 		status = ldc_mem_dring_unbind(vdc->dring_hdl);
2764 		if (status == 0) {
2765 			vdc->initialized &= ~VDC_DRING_BOUND;
2766 		} else {
2767 			DMSG(vdc, 0, "[%d] Error %d unbinding DRing %lx",
2768 			    vdc->instance, status, vdc->dring_hdl);
2769 		}
2770 		kmem_free(vdc->dring_cookie, sizeof (ldc_mem_cookie_t));
2771 	}
2772 
2773 	if (vdc->initialized & VDC_DRING_INIT) {
2774 		DMSG(vdc, 0, "[%d] Destroying DRing\n", vdc->instance);
2775 		status = ldc_mem_dring_destroy(vdc->dring_hdl);
2776 		if (status == 0) {
2777 			vdc->dring_hdl = NULL;
2778 			bzero(&vdc->dring_mem_info, sizeof (ldc_mem_info_t));
2779 			vdc->initialized &= ~VDC_DRING_INIT;
2780 		} else {
2781 			DMSG(vdc, 0, "[%d] Error %d destroying DRing (%lx)",
2782 			    vdc->instance, status, vdc->dring_hdl);
2783 		}
2784 	}
2785 }
2786 
2787 /*
2788  * Function:
2789  *	vdc_map_to_shared_dring()
2790  *
2791  * Description:
2792  *	Copy contents of the local descriptor to the shared
2793  *	memory descriptor.
2794  *
2795  * Arguments:
2796  *	vdcp	- soft state pointer for this instance of the device driver.
2797  *	idx	- descriptor ring index
2798  *
2799  * Return Code:
2800  *	None
2801  */
2802 static int
2803 vdc_map_to_shared_dring(vdc_t *vdcp, int idx)
2804 {
2805 	vdc_local_desc_t	*ldep;
2806 	vd_dring_entry_t	*dep;
2807 	int			rv;
2808 
2809 	ldep = &(vdcp->local_dring[idx]);
2810 
2811 	/* for now leave in the old pop_mem_hdl stuff */
2812 	if (ldep->nbytes > 0) {
2813 		rv = vdc_populate_mem_hdl(vdcp, ldep);
2814 		if (rv) {
2815 			DMSG(vdcp, 0, "[%d] Cannot populate mem handle\n",
2816 			    vdcp->instance);
2817 			return (rv);
2818 		}
2819 	}
2820 
2821 	/*
2822 	 * fill in the data details into the DRing
2823 	 */
2824 	dep = ldep->dep;
2825 	ASSERT(dep != NULL);
2826 
2827 	dep->payload.req_id = VDC_GET_NEXT_REQ_ID(vdcp);
2828 	dep->payload.operation = ldep->operation;
2829 	dep->payload.addr = ldep->offset;
2830 	dep->payload.nbytes = ldep->nbytes;
2831 	dep->payload.status = (uint32_t)-1;	/* vds will set valid value */
2832 	dep->payload.slice = ldep->slice;
2833 	dep->hdr.dstate = VIO_DESC_READY;
2834 	dep->hdr.ack = 1;		/* request an ACK for every message */
2835 
2836 	return (0);
2837 }
2838 
2839 /*
2840  * Function:
2841  *	vdc_send_request
2842  *
2843  * Description:
2844  *	This routine writes the data to be transmitted to vds into the
2845  *	descriptor, notifies vds that the ring has been updated and
2846  *	then waits for the request to be processed.
2847  *
2848  * Arguments:
2849  *	vdcp	  - the soft state pointer
2850  *	operation - operation we want vds to perform (VD_OP_XXX)
2851  *	addr	  - address of data buf to be read/written.
2852  *	nbytes	  - number of bytes to read/write
2853  *	slice	  - the disk slice this request is for
2854  *	offset	  - relative disk offset
2855  *	cb_type   - type of call - STRATEGY or SYNC
2856  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2857  *			. mode for ioctl(9e)
2858  *			. LP64 diskaddr_t (block I/O)
2859  *	dir	  - direction of operation (READ/WRITE/BOTH)
2860  *
2861  * Return Codes:
2862  *	0
2863  *	ENXIO
2864  */
2865 static int
2866 vdc_send_request(vdc_t *vdcp, int operation, caddr_t addr,
2867     size_t nbytes, int slice, diskaddr_t offset, int cb_type,
2868     void *cb_arg, vio_desc_direction_t dir)
2869 {
2870 	int	rv = 0;
2871 
2872 	ASSERT(vdcp != NULL);
2873 	ASSERT(slice == VD_SLICE_NONE || slice < V_NUMPAR);
2874 
2875 	mutex_enter(&vdcp->lock);
2876 
2877 	/*
2878 	 * If this is a block read/write operation we update the I/O statistics
2879 	 * to indicate that the request is being put on the waitq to be
2880 	 * serviced.
2881 	 *
2882 	 * We do it here (a common routine for both synchronous and strategy
2883 	 * calls) for performance reasons - we are already holding vdc->lock
2884 	 * so there is no extra locking overhead. We would have to explicitly
2885 	 * grab the 'lock' mutex to update the stats if we were to do this
2886 	 * higher up the stack in vdc_strategy() et. al.
2887 	 */
2888 	if ((operation == VD_OP_BREAD) || (operation == VD_OP_BWRITE)) {
2889 		DTRACE_IO1(start, buf_t *, cb_arg);
2890 		VD_KSTAT_WAITQ_ENTER(vdcp);
2891 	}
2892 
2893 	do {
2894 		while (vdcp->state != VDC_STATE_RUNNING) {
2895 
2896 			/* return error if detaching */
2897 			if (vdcp->state == VDC_STATE_DETACH) {
2898 				rv = ENXIO;
2899 				goto done;
2900 			}
2901 
2902 			/* fail request if connection timeout is reached */
2903 			if (vdcp->ctimeout_reached) {
2904 				rv = EIO;
2905 				goto done;
2906 			}
2907 
2908 			/*
2909 			 * If we are panicking and the disk is not ready then
2910 			 * we can't send any request because we can't complete
2911 			 * the handshake now.
2912 			 */
2913 			if (ddi_in_panic()) {
2914 				rv = EIO;
2915 				goto done;
2916 			}
2917 
2918 			cv_wait(&vdcp->running_cv, &vdcp->lock);
2919 		}
2920 
2921 	} while (vdc_populate_descriptor(vdcp, operation, addr,
2922 	    nbytes, slice, offset, cb_type, cb_arg, dir));
2923 
2924 done:
2925 	/*
2926 	 * If this is a block read/write we update the I/O statistics kstat
2927 	 * to indicate that this request has been placed on the queue for
2928 	 * processing (i.e sent to the vDisk server) - iostat(1M) will
2929 	 * report the time waiting for the vDisk server under the %b column
2930 	 * In the case of an error we simply take it off the wait queue.
2931 	 */
2932 	if ((operation == VD_OP_BREAD) || (operation == VD_OP_BWRITE)) {
2933 		if (rv == 0) {
2934 			VD_KSTAT_WAITQ_TO_RUNQ(vdcp);
2935 			DTRACE_PROBE1(send, buf_t *, cb_arg);
2936 		} else {
2937 			VD_UPDATE_ERR_STATS(vdcp, vd_transerrs);
2938 			VD_KSTAT_WAITQ_EXIT(vdcp);
2939 			DTRACE_IO1(done, buf_t *, cb_arg);
2940 		}
2941 	}
2942 
2943 	mutex_exit(&vdcp->lock);
2944 
2945 	return (rv);
2946 }
2947 
2948 
2949 /*
2950  * Function:
2951  *	vdc_populate_descriptor
2952  *
2953  * Description:
2954  *	This routine writes the data to be transmitted to vds into the
2955  *	descriptor, notifies vds that the ring has been updated and
2956  *	then waits for the request to be processed.
2957  *
2958  * Arguments:
2959  *	vdcp	  - the soft state pointer
2960  *	operation - operation we want vds to perform (VD_OP_XXX)
2961  *	addr	  - address of data buf to be read/written.
2962  *	nbytes	  - number of bytes to read/write
2963  *	slice	  - the disk slice this request is for
2964  *	offset	  - relative disk offset
2965  *	cb_type   - type of call - STRATEGY or SYNC
2966  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
2967  *			. mode for ioctl(9e)
2968  *			. LP64 diskaddr_t (block I/O)
2969  *	dir	  - direction of operation (READ/WRITE/BOTH)
2970  *
2971  * Return Codes:
2972  *	0
2973  *	EAGAIN
2974  *	ECONNRESET
2975  *	ENXIO
2976  */
2977 static int
2978 vdc_populate_descriptor(vdc_t *vdcp, int operation, caddr_t addr,
2979     size_t nbytes, int slice, diskaddr_t offset, int cb_type,
2980     void *cb_arg, vio_desc_direction_t dir)
2981 {
2982 	vdc_local_desc_t	*local_dep = NULL; /* Local Dring Pointer */
2983 	int			idx;		/* Index of DRing entry used */
2984 	int			next_idx;
2985 	vio_dring_msg_t		dmsg;
2986 	size_t			msglen;
2987 	int			rv;
2988 
2989 	ASSERT(MUTEX_HELD(&vdcp->lock));
2990 	vdcp->threads_pending++;
2991 loop:
2992 	DMSG(vdcp, 2, ": dring_curr_idx = %d\n", vdcp->dring_curr_idx);
2993 
2994 	/* Get next available D-Ring entry */
2995 	idx = vdcp->dring_curr_idx;
2996 	local_dep = &(vdcp->local_dring[idx]);
2997 
2998 	if (!local_dep->is_free) {
2999 		DMSG(vdcp, 2, "[%d]: dring full - waiting for space\n",
3000 		    vdcp->instance);
3001 		cv_wait(&vdcp->dring_free_cv, &vdcp->lock);
3002 		if (vdcp->state == VDC_STATE_RUNNING ||
3003 		    vdcp->state == VDC_STATE_HANDLE_PENDING) {
3004 			goto loop;
3005 		}
3006 		vdcp->threads_pending--;
3007 		return (ECONNRESET);
3008 	}
3009 
3010 	next_idx = idx + 1;
3011 	if (next_idx >= vdcp->dring_len)
3012 		next_idx = 0;
3013 	vdcp->dring_curr_idx = next_idx;
3014 
3015 	ASSERT(local_dep->is_free);
3016 
3017 	local_dep->operation = operation;
3018 	local_dep->addr = addr;
3019 	local_dep->nbytes = nbytes;
3020 	local_dep->slice = slice;
3021 	local_dep->offset = offset;
3022 	local_dep->cb_type = cb_type;
3023 	local_dep->cb_arg = cb_arg;
3024 	local_dep->dir = dir;
3025 
3026 	local_dep->is_free = B_FALSE;
3027 
3028 	rv = vdc_map_to_shared_dring(vdcp, idx);
3029 	if (rv) {
3030 		DMSG(vdcp, 0, "[%d]: cannot bind memory - waiting ..\n",
3031 		    vdcp->instance);
3032 		/* free the descriptor */
3033 		local_dep->is_free = B_TRUE;
3034 		vdcp->dring_curr_idx = idx;
3035 		cv_wait(&vdcp->membind_cv, &vdcp->lock);
3036 		if (vdcp->state == VDC_STATE_RUNNING ||
3037 		    vdcp->state == VDC_STATE_HANDLE_PENDING) {
3038 			goto loop;
3039 		}
3040 		vdcp->threads_pending--;
3041 		return (ECONNRESET);
3042 	}
3043 
3044 	/*
3045 	 * Send a msg with the DRing details to vds
3046 	 */
3047 	VIO_INIT_DRING_DATA_TAG(dmsg);
3048 	VDC_INIT_DRING_DATA_MSG_IDS(dmsg, vdcp);
3049 	dmsg.dring_ident = vdcp->dring_ident;
3050 	dmsg.start_idx = idx;
3051 	dmsg.end_idx = idx;
3052 	vdcp->seq_num++;
3053 
3054 	DTRACE_PROBE2(populate, int, vdcp->instance,
3055 	    vdc_local_desc_t *, local_dep);
3056 	DMSG(vdcp, 2, "ident=0x%lx, st=%u, end=%u, seq=%ld\n",
3057 	    vdcp->dring_ident, dmsg.start_idx, dmsg.end_idx, dmsg.seq_num);
3058 
3059 	/*
3060 	 * note we're still holding the lock here to
3061 	 * make sure the message goes out in order !!!...
3062 	 */
3063 	msglen = sizeof (dmsg);
3064 	rv = vdc_send(vdcp, (caddr_t)&dmsg, &msglen);
3065 	switch (rv) {
3066 	case ECONNRESET:
3067 		/*
3068 		 * vdc_send initiates the reset on failure.
3069 		 * Since the transaction has already been put
3070 		 * on the local dring, it will automatically get
3071 		 * retried when the channel is reset. Given that,
3072 		 * it is ok to just return success even though the
3073 		 * send failed.
3074 		 */
3075 		rv = 0;
3076 		break;
3077 
3078 	case 0: /* EOK */
3079 		DMSG(vdcp, 1, "sent via LDC: rv=%d\n", rv);
3080 		break;
3081 
3082 	default:
3083 		goto cleanup_and_exit;
3084 	}
3085 
3086 	vdcp->threads_pending--;
3087 	return (rv);
3088 
3089 cleanup_and_exit:
3090 	DMSG(vdcp, 0, "unexpected error, rv=%d\n", rv);
3091 	return (ENXIO);
3092 }
3093 
3094 /*
3095  * Function:
3096  *	vdc_do_sync_op
3097  *
3098  * Description:
3099  * 	Wrapper around vdc_populate_descriptor that blocks until the
3100  * 	response to the message is available.
3101  *
3102  * Arguments:
3103  *	vdcp	  - the soft state pointer
3104  *	operation - operation we want vds to perform (VD_OP_XXX)
3105  *	addr	  - address of data buf to be read/written.
3106  *	nbytes	  - number of bytes to read/write
3107  *	slice	  - the disk slice this request is for
3108  *	offset	  - relative disk offset
3109  *	cb_type   - type of call - STRATEGY or SYNC
3110  *	cb_arg	  - parameter to be sent to server (depends on VD_OP_XXX type)
3111  *			. mode for ioctl(9e)
3112  *			. LP64 diskaddr_t (block I/O)
3113  *	dir	  - direction of operation (READ/WRITE/BOTH)
3114  *	rconflict - check for reservation conflict in case of failure
3115  *
3116  * rconflict should be set to B_TRUE by most callers. Callers invoking the
3117  * VD_OP_SCSICMD operation can set rconflict to B_FALSE if they check the
3118  * result of a successful operation with vd_scsi_status().
3119  *
3120  * Return Codes:
3121  *	0
3122  *	EAGAIN
3123  *	EFAULT
3124  *	ENXIO
3125  *	EIO
3126  */
3127 static int
3128 vdc_do_sync_op(vdc_t *vdcp, int operation, caddr_t addr, size_t nbytes,
3129     int slice, diskaddr_t offset, int cb_type, void *cb_arg,
3130     vio_desc_direction_t dir, boolean_t rconflict)
3131 {
3132 	int status;
3133 	vdc_io_t *vio;
3134 	boolean_t check_resv_conflict = B_FALSE;
3135 
3136 	ASSERT(cb_type == CB_SYNC);
3137 
3138 	/*
3139 	 * Grab the lock, if blocked wait until the server
3140 	 * response causes us to wake up again.
3141 	 */
3142 	mutex_enter(&vdcp->lock);
3143 	vdcp->sync_op_cnt++;
3144 	while (vdcp->sync_op_blocked && vdcp->state != VDC_STATE_DETACH)
3145 		cv_wait(&vdcp->sync_blocked_cv, &vdcp->lock);
3146 
3147 	if (vdcp->state == VDC_STATE_DETACH) {
3148 		cv_broadcast(&vdcp->sync_blocked_cv);
3149 		vdcp->sync_op_cnt--;
3150 		mutex_exit(&vdcp->lock);
3151 		return (ENXIO);
3152 	}
3153 
3154 	/* now block anyone other thread entering after us */
3155 	vdcp->sync_op_blocked = B_TRUE;
3156 	vdcp->sync_op_pending = B_TRUE;
3157 	mutex_exit(&vdcp->lock);
3158 
3159 	status = vdc_send_request(vdcp, operation, addr,
3160 	    nbytes, slice, offset, cb_type, cb_arg, dir);
3161 
3162 	mutex_enter(&vdcp->lock);
3163 
3164 	if (status != 0) {
3165 		vdcp->sync_op_pending = B_FALSE;
3166 	} else {
3167 		/*
3168 		 * block until our transaction completes.
3169 		 * Also anyone else waiting also gets to go next.
3170 		 */
3171 		while (vdcp->sync_op_pending && vdcp->state != VDC_STATE_DETACH)
3172 			cv_wait(&vdcp->sync_pending_cv, &vdcp->lock);
3173 
3174 		DMSG(vdcp, 2, ": operation returned %d\n",
3175 		    vdcp->sync_op_status);
3176 		if (vdcp->state == VDC_STATE_DETACH) {
3177 			vdcp->sync_op_pending = B_FALSE;
3178 			status = ENXIO;
3179 		} else {
3180 			status = vdcp->sync_op_status;
3181 			if (status != 0 && vdcp->failfast_interval != 0) {
3182 				/*
3183 				 * Operation has failed and failfast is enabled.
3184 				 * We need to check if the failure is due to a
3185 				 * reservation conflict if this was requested.
3186 				 */
3187 				check_resv_conflict = rconflict;
3188 			}
3189 
3190 		}
3191 	}
3192 
3193 	vdcp->sync_op_status = 0;
3194 	vdcp->sync_op_blocked = B_FALSE;
3195 	vdcp->sync_op_cnt--;
3196 
3197 	/* signal the next waiting thread */
3198 	cv_signal(&vdcp->sync_blocked_cv);
3199 
3200 	/*
3201 	 * We have to check for reservation conflict after unblocking sync
3202 	 * operations because some sync operations will be used to do this
3203 	 * check.
3204 	 */
3205 	if (check_resv_conflict) {
3206 		vio = vdc_failfast_io_queue(vdcp, NULL);
3207 		while (vio->vio_qtime != 0)
3208 			cv_wait(&vdcp->failfast_io_cv, &vdcp->lock);
3209 		kmem_free(vio, sizeof (vdc_io_t));
3210 	}
3211 
3212 	mutex_exit(&vdcp->lock);
3213 
3214 	return (status);
3215 }
3216 
3217 
3218 /*
3219  * Function:
3220  *	vdc_drain_response()
3221  *
3222  * Description:
3223  * 	When a guest is panicking, the completion of requests needs to be
3224  * 	handled differently because interrupts are disabled and vdc
3225  * 	will not get messages. We have to poll for the messages instead.
3226  *
3227  *	Note: since we are panicking we don't implement	the io:::done
3228  *	DTrace probe or update the I/O statistics kstats.
3229  *
3230  * Arguments:
3231  *	vdc	- soft state pointer for this instance of the device driver.
3232  *	buf	- if buf is NULL then we drain all responses, otherwise we
3233  *		  poll until we receive a ACK/NACK for the specific I/O
3234  *		  described by buf.
3235  *
3236  * Return Code:
3237  *	0	- Success
3238  */
3239 static int
3240 vdc_drain_response(vdc_t *vdc, struct buf *buf)
3241 {
3242 	int 			rv, idx, retries;
3243 	size_t			msglen;
3244 	vdc_local_desc_t 	*ldep = NULL;	/* Local Dring Entry Pointer */
3245 	vio_dring_msg_t		dmsg;
3246 	struct buf		*mbuf;
3247 
3248 	mutex_enter(&vdc->lock);
3249 
3250 	retries = 0;
3251 	for (;;) {
3252 		msglen = sizeof (dmsg);
3253 		rv = ldc_read(vdc->curr_server->ldc_handle, (caddr_t)&dmsg,
3254 		    &msglen);
3255 		if (rv) {
3256 			rv = EINVAL;
3257 			break;
3258 		}
3259 
3260 		/*
3261 		 * if there are no packets wait and check again
3262 		 */
3263 		if ((rv == 0) && (msglen == 0)) {
3264 			if (retries++ > vdc_dump_retries) {
3265 				rv = EAGAIN;
3266 				break;
3267 			}
3268 
3269 			drv_usecwait(vdc_usec_timeout_dump);
3270 			continue;
3271 		}
3272 
3273 		/*
3274 		 * Ignore all messages that are not ACKs/NACKs to
3275 		 * DRing requests.
3276 		 */
3277 		if ((dmsg.tag.vio_msgtype != VIO_TYPE_DATA) ||
3278 		    (dmsg.tag.vio_subtype_env != VIO_DRING_DATA)) {
3279 			DMSG(vdc, 0, "discard pkt: type=%d sub=%d env=%d\n",
3280 			    dmsg.tag.vio_msgtype,
3281 			    dmsg.tag.vio_subtype,
3282 			    dmsg.tag.vio_subtype_env);
3283 			continue;
3284 		}
3285 
3286 		/*
3287 		 * set the appropriate return value for the current request.
3288 		 */
3289 		switch (dmsg.tag.vio_subtype) {
3290 		case VIO_SUBTYPE_ACK:
3291 			rv = 0;
3292 			break;
3293 		case VIO_SUBTYPE_NACK:
3294 			rv = EAGAIN;
3295 			break;
3296 		default:
3297 			continue;
3298 		}
3299 
3300 		idx = dmsg.start_idx;
3301 		if (idx >= vdc->dring_len) {
3302 			DMSG(vdc, 0, "[%d] Bogus ack data : start %d\n",
3303 			    vdc->instance, idx);
3304 			continue;
3305 		}
3306 		ldep = &vdc->local_dring[idx];
3307 		if (ldep->dep->hdr.dstate != VIO_DESC_DONE) {
3308 			DMSG(vdc, 0, "[%d] Entry @ %d - state !DONE %d\n",
3309 			    vdc->instance, idx, ldep->dep->hdr.dstate);
3310 			continue;
3311 		}
3312 
3313 		if (buf != NULL && ldep->cb_type == CB_STRATEGY) {
3314 			mbuf = ldep->cb_arg;
3315 			mbuf->b_resid = mbuf->b_bcount -
3316 			    ldep->dep->payload.nbytes;
3317 			bioerror(mbuf, (rv == EAGAIN)? EIO:
3318 			    ldep->dep->payload.status);
3319 			biodone(mbuf);
3320 		} else {
3321 			mbuf = NULL;
3322 		}
3323 
3324 		DMSG(vdc, 1, "[%d] Depopulating idx=%d state=%d\n",
3325 		    vdc->instance, idx, ldep->dep->hdr.dstate);
3326 
3327 		rv = vdc_depopulate_descriptor(vdc, idx);
3328 		if (rv) {
3329 			DMSG(vdc, 0,
3330 			    "[%d] Entry @ %d - depopulate failed ..\n",
3331 			    vdc->instance, idx);
3332 		}
3333 
3334 		/* we have received an ACK/NACK for the specified buffer */
3335 		if (buf != NULL && buf == mbuf) {
3336 			rv = 0;
3337 			break;
3338 		}
3339 
3340 		/* if this is the last descriptor - break out of loop */
3341 		if ((idx + 1) % vdc->dring_len == vdc->dring_curr_idx) {
3342 			if (buf != NULL) {
3343 				/*
3344 				 * We never got a response for the specified
3345 				 * buffer so we fail the I/O.
3346 				 */
3347 				bioerror(buf, EIO);
3348 				biodone(buf);
3349 			}
3350 			break;
3351 		}
3352 	}
3353 
3354 	mutex_exit(&vdc->lock);
3355 	DMSG(vdc, 0, "End idx=%d\n", idx);
3356 
3357 	return (rv);
3358 }
3359 
3360 
3361 /*
3362  * Function:
3363  *	vdc_depopulate_descriptor()
3364  *
3365  * Description:
3366  *
3367  * Arguments:
3368  *	vdc	- soft state pointer for this instance of the device driver.
3369  *	idx	- Index of the Descriptor Ring entry being modified
3370  *
3371  * Return Code:
3372  *	0	- Success
3373  */
3374 static int
3375 vdc_depopulate_descriptor(vdc_t *vdc, uint_t idx)
3376 {
3377 	vd_dring_entry_t *dep = NULL;		/* Dring Entry Pointer */
3378 	vdc_local_desc_t *ldep = NULL;		/* Local Dring Entry Pointer */
3379 	int		status = ENXIO;
3380 	int		rv = 0;
3381 
3382 	ASSERT(vdc != NULL);
3383 	ASSERT(idx < vdc->dring_len);
3384 	ldep = &vdc->local_dring[idx];
3385 	ASSERT(ldep != NULL);
3386 	ASSERT(MUTEX_HELD(&vdc->lock));
3387 
3388 	DTRACE_PROBE2(depopulate, int, vdc->instance, vdc_local_desc_t *, ldep);
3389 	DMSG(vdc, 2, ": idx = %d\n", idx);
3390 
3391 	dep = ldep->dep;
3392 	ASSERT(dep != NULL);
3393 	ASSERT((dep->hdr.dstate == VIO_DESC_DONE) ||
3394 	    (dep->payload.status == ECANCELED));
3395 
3396 	VDC_MARK_DRING_ENTRY_FREE(vdc, idx);
3397 
3398 	ldep->is_free = B_TRUE;
3399 	status = dep->payload.status;
3400 	DMSG(vdc, 2, ": is_free = %d : status = %d\n", ldep->is_free, status);
3401 
3402 	/*
3403 	 * If no buffers were used to transfer information to the server when
3404 	 * populating the descriptor then no memory handles need to be unbound
3405 	 * and we can return now.
3406 	 */
3407 	if (ldep->nbytes == 0) {
3408 		cv_signal(&vdc->dring_free_cv);
3409 		return (status);
3410 	}
3411 
3412 	/*
3413 	 * If the upper layer passed in a misaligned address we copied the
3414 	 * data into an aligned buffer before sending it to LDC - we now
3415 	 * copy it back to the original buffer.
3416 	 */
3417 	if (ldep->align_addr) {
3418 		ASSERT(ldep->addr != NULL);
3419 
3420 		if (dep->payload.nbytes > 0)
3421 			bcopy(ldep->align_addr, ldep->addr,
3422 			    dep->payload.nbytes);
3423 		kmem_free(ldep->align_addr,
3424 		    sizeof (caddr_t) * P2ROUNDUP(ldep->nbytes, 8));
3425 		ldep->align_addr = NULL;
3426 	}
3427 
3428 	rv = ldc_mem_unbind_handle(ldep->desc_mhdl);
3429 	if (rv != 0) {
3430 		DMSG(vdc, 0, "?[%d] unbind mhdl 0x%lx @ idx %d failed (%d)",
3431 		    vdc->instance, ldep->desc_mhdl, idx, rv);
3432 		/*
3433 		 * The error returned by the vDisk server is more informative
3434 		 * and thus has a higher priority but if it isn't set we ensure
3435 		 * that this function returns an error.
3436 		 */
3437 		if (status == 0)
3438 			status = EINVAL;
3439 	}
3440 
3441 	cv_signal(&vdc->membind_cv);
3442 	cv_signal(&vdc->dring_free_cv);
3443 
3444 	return (status);
3445 }
3446 
3447 /*
3448  * Function:
3449  *	vdc_populate_mem_hdl()
3450  *
3451  * Description:
3452  *
3453  * Arguments:
3454  *	vdc	- soft state pointer for this instance of the device driver.
3455  *	idx	- Index of the Descriptor Ring entry being modified
3456  *	addr	- virtual address being mapped in
3457  *	nybtes	- number of bytes in 'addr'
3458  *	operation - the vDisk operation being performed (VD_OP_xxx)
3459  *
3460  * Return Code:
3461  *	0	- Success
3462  */
3463 static int
3464 vdc_populate_mem_hdl(vdc_t *vdcp, vdc_local_desc_t *ldep)
3465 {
3466 	vd_dring_entry_t	*dep = NULL;
3467 	ldc_mem_handle_t	mhdl;
3468 	caddr_t			vaddr;
3469 	size_t			nbytes;
3470 	uint8_t			perm = LDC_MEM_RW;
3471 	uint8_t			maptype;
3472 	int			rv = 0;
3473 	int			i;
3474 
3475 	ASSERT(vdcp != NULL);
3476 
3477 	dep = ldep->dep;
3478 	mhdl = ldep->desc_mhdl;
3479 
3480 	switch (ldep->dir) {
3481 	case VIO_read_dir:
3482 		perm = LDC_MEM_W;
3483 		break;
3484 
3485 	case VIO_write_dir:
3486 		perm = LDC_MEM_R;
3487 		break;
3488 
3489 	case VIO_both_dir:
3490 		perm = LDC_MEM_RW;
3491 		break;
3492 
3493 	default:
3494 		ASSERT(0);	/* catch bad programming in vdc */
3495 	}
3496 
3497 	/*
3498 	 * LDC expects any addresses passed in to be 8-byte aligned. We need
3499 	 * to copy the contents of any misaligned buffers to a newly allocated
3500 	 * buffer and bind it instead (and copy the the contents back to the
3501 	 * original buffer passed in when depopulating the descriptor)
3502 	 */
3503 	vaddr = ldep->addr;
3504 	nbytes = ldep->nbytes;
3505 	if (((uint64_t)vaddr & 0x7) != 0) {
3506 		ASSERT(ldep->align_addr == NULL);
3507 		ldep->align_addr =
3508 		    kmem_alloc(sizeof (caddr_t) *
3509 		    P2ROUNDUP(nbytes, 8), KM_SLEEP);
3510 		DMSG(vdcp, 0, "[%d] Misaligned address %p reallocating "
3511 		    "(buf=%p nb=%ld op=%d)\n",
3512 		    vdcp->instance, (void *)vaddr, (void *)ldep->align_addr,
3513 		    nbytes, ldep->operation);
3514 		if (perm != LDC_MEM_W)
3515 			bcopy(vaddr, ldep->align_addr, nbytes);
3516 		vaddr = ldep->align_addr;
3517 	}
3518 
3519 	maptype = LDC_IO_MAP|LDC_SHADOW_MAP|LDC_DIRECT_MAP;
3520 	rv = ldc_mem_bind_handle(mhdl, vaddr, P2ROUNDUP(nbytes, 8),
3521 	    maptype, perm, &dep->payload.cookie[0], &dep->payload.ncookies);
3522 	DMSG(vdcp, 2, "[%d] bound mem handle; ncookies=%d\n",
3523 	    vdcp->instance, dep->payload.ncookies);
3524 	if (rv != 0) {
3525 		DMSG(vdcp, 0, "[%d] Failed to bind LDC memory handle "
3526 		    "(mhdl=%p, buf=%p, err=%d)\n",
3527 		    vdcp->instance, (void *)mhdl, (void *)vaddr, rv);
3528 		if (ldep->align_addr) {
3529 			kmem_free(ldep->align_addr,
3530 			    sizeof (caddr_t) * P2ROUNDUP(nbytes, 8));
3531 			ldep->align_addr = NULL;
3532 		}
3533 		return (EAGAIN);
3534 	}
3535 
3536 	/*
3537 	 * Get the other cookies (if any).
3538 	 */
3539 	for (i = 1; i < dep->payload.ncookies; i++) {
3540 		rv = ldc_mem_nextcookie(mhdl, &dep->payload.cookie[i]);
3541 		if (rv != 0) {
3542 			(void) ldc_mem_unbind_handle(mhdl);
3543 			DMSG(vdcp, 0, "?[%d] Failed to get next cookie "
3544 			    "(mhdl=%lx cnum=%d), err=%d",
3545 			    vdcp->instance, mhdl, i, rv);
3546 			if (ldep->align_addr) {
3547 				kmem_free(ldep->align_addr,
3548 				    sizeof (caddr_t) * ldep->nbytes);
3549 				ldep->align_addr = NULL;
3550 			}
3551 			return (EAGAIN);
3552 		}
3553 	}
3554 
3555 	return (rv);
3556 }
3557 
3558 /*
3559  * Interrupt handlers for messages from LDC
3560  */
3561 
3562 /*
3563  * Function:
3564  *	vdc_handle_cb()
3565  *
3566  * Description:
3567  *
3568  * Arguments:
3569  *	event	- Type of event (LDC_EVT_xxx) that triggered the callback
3570  *	arg	- soft state pointer for this instance of the device driver.
3571  *
3572  * Return Code:
3573  *	0	- Success
3574  */
3575 static uint_t
3576 vdc_handle_cb(uint64_t event, caddr_t arg)
3577 {
3578 	ldc_status_t	ldc_state;
3579 	int		rv = 0;
3580 	vdc_server_t	*srvr = (vdc_server_t *)(void *)arg;
3581 	vdc_t		*vdc = srvr->vdcp;
3582 
3583 	ASSERT(vdc != NULL);
3584 
3585 	DMSG(vdc, 1, "evt=%lx seqID=%ld\n", event, vdc->seq_num);
3586 
3587 	/* If callback is not for the current server, ignore it */
3588 	mutex_enter(&vdc->lock);
3589 
3590 	if (vdc->curr_server != srvr) {
3591 		DMSG(vdc, 0, "[%d] Ignoring event 0x%lx for port@%ld\n",
3592 		    vdc->instance, event, srvr->id);
3593 		mutex_exit(&vdc->lock);
3594 		return (LDC_SUCCESS);
3595 	}
3596 
3597 	/*
3598 	 * Depending on the type of event that triggered this callback,
3599 	 * we modify the handshake state or read the data.
3600 	 *
3601 	 * NOTE: not done as a switch() as event could be triggered by
3602 	 * a state change and a read request. Also the ordering	of the
3603 	 * check for the event types is deliberate.
3604 	 */
3605 	if (event & LDC_EVT_UP) {
3606 		DMSG(vdc, 0, "[%d] Received LDC_EVT_UP\n", vdc->instance);
3607 
3608 		/* get LDC state */
3609 		rv = ldc_status(srvr->ldc_handle, &ldc_state);
3610 		if (rv != 0) {
3611 			DMSG(vdc, 0, "[%d] Couldn't get LDC status %d",
3612 			    vdc->instance, rv);
3613 			mutex_exit(&vdc->lock);
3614 			return (LDC_SUCCESS);
3615 		}
3616 		if (srvr->ldc_state != LDC_UP &&
3617 		    ldc_state == LDC_UP) {
3618 			/*
3619 			 * Reset the transaction sequence numbers when
3620 			 * LDC comes up. We then kick off the handshake
3621 			 * negotiation with the vDisk server.
3622 			 */
3623 			vdc->seq_num = 1;
3624 			vdc->seq_num_reply = 0;
3625 			srvr->ldc_state = ldc_state;
3626 			cv_signal(&vdc->initwait_cv);
3627 		}
3628 	}
3629 
3630 	if (event & LDC_EVT_READ) {
3631 		DMSG(vdc, 1, "[%d] Received LDC_EVT_READ\n", vdc->instance);
3632 		mutex_enter(&vdc->read_lock);
3633 		cv_signal(&vdc->read_cv);
3634 		vdc->read_state = VDC_READ_PENDING;
3635 		mutex_exit(&vdc->read_lock);
3636 		mutex_exit(&vdc->lock);
3637 
3638 		/* that's all we have to do - no need to handle DOWN/RESET */
3639 		return (LDC_SUCCESS);
3640 	}
3641 
3642 	if (event & (LDC_EVT_RESET|LDC_EVT_DOWN)) {
3643 
3644 		DMSG(vdc, 0, "[%d] Received LDC RESET event\n", vdc->instance);
3645 
3646 		/*
3647 		 * Need to wake up any readers so they will
3648 		 * detect that a reset has occurred.
3649 		 */
3650 		mutex_enter(&vdc->read_lock);
3651 		if ((vdc->read_state == VDC_READ_WAITING) ||
3652 		    (vdc->read_state == VDC_READ_RESET))
3653 			cv_signal(&vdc->read_cv);
3654 		vdc->read_state = VDC_READ_RESET;
3655 		mutex_exit(&vdc->read_lock);
3656 
3657 		/* wake up any threads waiting for connection to come up */
3658 		if (vdc->state == VDC_STATE_INIT_WAITING) {
3659 			vdc->state = VDC_STATE_RESETTING;
3660 			cv_signal(&vdc->initwait_cv);
3661 		}
3662 
3663 	}
3664 
3665 	mutex_exit(&vdc->lock);
3666 
3667 	if (event & ~(LDC_EVT_UP | LDC_EVT_RESET | LDC_EVT_DOWN | LDC_EVT_READ))
3668 		DMSG(vdc, 0, "![%d] Unexpected LDC event (%lx) received",
3669 		    vdc->instance, event);
3670 
3671 	return (LDC_SUCCESS);
3672 }
3673 
3674 /*
3675  * Function:
3676  *	vdc_wait_for_response()
3677  *
3678  * Description:
3679  *	Block waiting for a response from the server. If there is
3680  *	no data the thread block on the read_cv that is signalled
3681  *	by the callback when an EVT_READ occurs.
3682  *
3683  * Arguments:
3684  *	vdcp	- soft state pointer for this instance of the device driver.
3685  *
3686  * Return Code:
3687  *	0	- Success
3688  */
3689 static int
3690 vdc_wait_for_response(vdc_t *vdcp, vio_msg_t *msgp)
3691 {
3692 	size_t		nbytes = sizeof (*msgp);
3693 	int		status;
3694 
3695 	ASSERT(vdcp != NULL);
3696 
3697 	DMSG(vdcp, 1, "[%d] Entered\n", vdcp->instance);
3698 
3699 	status = vdc_recv(vdcp, msgp, &nbytes);
3700 	DMSG(vdcp, 3, "vdc_read() done.. status=0x%x size=0x%x\n",
3701 	    status, (int)nbytes);
3702 	if (status) {
3703 		DMSG(vdcp, 0, "?[%d] Error %d reading LDC msg\n",
3704 		    vdcp->instance, status);
3705 		return (status);
3706 	}
3707 
3708 	if (nbytes < sizeof (vio_msg_tag_t)) {
3709 		DMSG(vdcp, 0, "?[%d] Expect %lu bytes; recv'd %lu\n",
3710 		    vdcp->instance, sizeof (vio_msg_tag_t), nbytes);
3711 		return (ENOMSG);
3712 	}
3713 
3714 	DMSG(vdcp, 2, "[%d] (%x/%x/%x)\n", vdcp->instance,
3715 	    msgp->tag.vio_msgtype,
3716 	    msgp->tag.vio_subtype,
3717 	    msgp->tag.vio_subtype_env);
3718 
3719 	/*
3720 	 * Verify the Session ID of the message
3721 	 *
3722 	 * Every message after the Version has been negotiated should
3723 	 * have the correct session ID set.
3724 	 */
3725 	if ((msgp->tag.vio_sid != vdcp->session_id) &&
3726 	    (msgp->tag.vio_subtype_env != VIO_VER_INFO)) {
3727 		DMSG(vdcp, 0, "[%d] Invalid SID: received 0x%x, "
3728 		    "expected 0x%lx [seq num %lx @ %d]",
3729 		    vdcp->instance, msgp->tag.vio_sid,
3730 		    vdcp->session_id,
3731 		    ((vio_dring_msg_t *)msgp)->seq_num,
3732 		    ((vio_dring_msg_t *)msgp)->start_idx);
3733 		return (ENOMSG);
3734 	}
3735 	return (0);
3736 }
3737 
3738 
3739 /*
3740  * Function:
3741  *	vdc_resubmit_backup_dring()
3742  *
3743  * Description:
3744  *	Resubmit each descriptor in the backed up dring to
3745  * 	vDisk server. The Dring was backed up during connection
3746  *	reset.
3747  *
3748  * Arguments:
3749  *	vdcp	- soft state pointer for this instance of the device driver.
3750  *
3751  * Return Code:
3752  *	0	- Success
3753  */
3754 static int
3755 vdc_resubmit_backup_dring(vdc_t *vdcp)
3756 {
3757 	int		processed = 0;
3758 	int		count;
3759 	int		b_idx;
3760 	int		rv = 0;
3761 	int		dring_size;
3762 	int		op;
3763 	vio_msg_t	vio_msg;
3764 	vdc_local_desc_t	*curr_ldep;
3765 
3766 	ASSERT(MUTEX_NOT_HELD(&vdcp->lock));
3767 	ASSERT(vdcp->state == VDC_STATE_HANDLE_PENDING);
3768 
3769 	if (vdcp->local_dring_backup == NULL) {
3770 		/* the pending requests have already been processed */
3771 		return (0);
3772 	}
3773 
3774 	DMSG(vdcp, 1, "restoring pending dring entries (len=%d, tail=%d)\n",
3775 	    vdcp->local_dring_backup_len, vdcp->local_dring_backup_tail);
3776 
3777 	/*
3778 	 * Walk the backup copy of the local descriptor ring and
3779 	 * resubmit all the outstanding transactions.
3780 	 */
3781 	b_idx = vdcp->local_dring_backup_tail;
3782 	for (count = 0; count < vdcp->local_dring_backup_len; count++) {
3783 
3784 		curr_ldep = &(vdcp->local_dring_backup[b_idx]);
3785 
3786 		/* only resubmit outstanding transactions */
3787 		if (!curr_ldep->is_free) {
3788 			/*
3789 			 * If we are retrying a block read/write operation we
3790 			 * need to update the I/O statistics to indicate that
3791 			 * the request is being put back on the waitq to be
3792 			 * serviced (it will have been taken off after the
3793 			 * error was reported).
3794 			 */
3795 			mutex_enter(&vdcp->lock);
3796 			op = curr_ldep->operation;
3797 			if ((op == VD_OP_BREAD) || (op == VD_OP_BWRITE)) {
3798 				DTRACE_IO1(start, buf_t *, curr_ldep->cb_arg);
3799 				VD_KSTAT_WAITQ_ENTER(vdcp);
3800 			}
3801 
3802 			DMSG(vdcp, 1, "resubmitting entry idx=%x\n", b_idx);
3803 			rv = vdc_populate_descriptor(vdcp, op,
3804 			    curr_ldep->addr, curr_ldep->nbytes,
3805 			    curr_ldep->slice, curr_ldep->offset,
3806 			    curr_ldep->cb_type, curr_ldep->cb_arg,
3807 			    curr_ldep->dir);
3808 
3809 			if (rv) {
3810 				if (op == VD_OP_BREAD || op == VD_OP_BWRITE) {
3811 					VD_UPDATE_ERR_STATS(vdcp, vd_transerrs);
3812 					VD_KSTAT_WAITQ_EXIT(vdcp);
3813 					DTRACE_IO1(done, buf_t *,
3814 					    curr_ldep->cb_arg);
3815 				}
3816 				DMSG(vdcp, 1, "[%d] cannot resubmit entry %d\n",
3817 				    vdcp->instance, b_idx);
3818 				mutex_exit(&vdcp->lock);
3819 				goto done;
3820 			}
3821 
3822 			/*
3823 			 * If this is a block read/write we update the I/O
3824 			 * statistics kstat to indicate that the request
3825 			 * has been sent back to the vDisk server and should
3826 			 * now be put on the run queue.
3827 			 */
3828 			if ((op == VD_OP_BREAD) || (op == VD_OP_BWRITE)) {
3829 				DTRACE_PROBE1(send, buf_t *, curr_ldep->cb_arg);
3830 				VD_KSTAT_WAITQ_TO_RUNQ(vdcp);
3831 			}
3832 			mutex_exit(&vdcp->lock);
3833 
3834 			/* Wait for the response message. */
3835 			DMSG(vdcp, 1, "waiting for response to idx=%x\n",
3836 			    b_idx);
3837 			rv = vdc_wait_for_response(vdcp, &vio_msg);
3838 			if (rv) {
3839 				/*
3840 				 * If this is a block read/write we update
3841 				 * the I/O statistics kstat to take it
3842 				 * off the run queue.
3843 				 */
3844 				mutex_enter(&vdcp->lock);
3845 				if (op == VD_OP_BREAD || op == VD_OP_BWRITE) {
3846 					VD_UPDATE_ERR_STATS(vdcp, vd_transerrs);
3847 					VD_KSTAT_RUNQ_EXIT(vdcp);
3848 					DTRACE_IO1(done, buf_t *,
3849 					    curr_ldep->cb_arg);
3850 				}
3851 				DMSG(vdcp, 1, "[%d] wait_for_response "
3852 				    "returned err=%d\n", vdcp->instance,
3853 				    rv);
3854 				mutex_exit(&vdcp->lock);
3855 				goto done;
3856 			}
3857 
3858 			DMSG(vdcp, 1, "processing msg for idx=%x\n", b_idx);
3859 			rv = vdc_process_data_msg(vdcp, &vio_msg);
3860 			if (rv) {
3861 				DMSG(vdcp, 1, "[%d] process_data_msg "
3862 				    "returned err=%d\n", vdcp->instance,
3863 				    rv);
3864 				goto done;
3865 			}
3866 			/*
3867 			 * Mark this entry as free so that we will not resubmit
3868 			 * this "done" request again, if we were to use the same
3869 			 * backup_dring again in future. This could happen when
3870 			 * a reset happens while processing the backup_dring.
3871 			 */
3872 			curr_ldep->is_free = B_TRUE;
3873 			processed++;
3874 		}
3875 
3876 		/* get the next element to submit */
3877 		if (++b_idx >= vdcp->local_dring_backup_len)
3878 			b_idx = 0;
3879 	}
3880 
3881 	/* all done - now clear up pending dring copy */
3882 	dring_size = vdcp->local_dring_backup_len *
3883 	    sizeof (vdcp->local_dring_backup[0]);
3884 
3885 	(void) kmem_free(vdcp->local_dring_backup, dring_size);
3886 
3887 	vdcp->local_dring_backup = NULL;
3888 
3889 done:
3890 	DTRACE_PROBE2(processed, int, processed, vdc_t *, vdcp);
3891 
3892 	return (rv);
3893 }
3894 
3895 /*
3896  * Function:
3897  *	vdc_cancel_backup_dring
3898  *
3899  * Description:
3900  *	Cancel each descriptor in the backed up dring to vDisk server.
3901  *	The Dring was backed up during connection reset.
3902  *
3903  * Arguments:
3904  *	vdcp	- soft state pointer for this instance of the device driver.
3905  *
3906  * Return Code:
3907  *	None
3908  */
3909 void
3910 vdc_cancel_backup_dring(vdc_t *vdcp)
3911 {
3912 	vdc_local_desc_t *ldep;
3913 	struct buf 	*bufp;
3914 	int		count;
3915 	int		b_idx;
3916 	int		dring_size;
3917 	int		cancelled = 0;
3918 
3919 	ASSERT(MUTEX_HELD(&vdcp->lock));
3920 	ASSERT(vdcp->state == VDC_STATE_INIT ||
3921 	    vdcp->state == VDC_STATE_INIT_WAITING ||
3922 	    vdcp->state == VDC_STATE_NEGOTIATE ||
3923 	    vdcp->state == VDC_STATE_RESETTING);
3924 
3925 	if (vdcp->local_dring_backup == NULL) {
3926 		/* the pending requests have already been processed */
3927 		return;
3928 	}
3929 
3930 	DMSG(vdcp, 1, "cancelling pending dring entries (len=%d, tail=%d)\n",
3931 	    vdcp->local_dring_backup_len, vdcp->local_dring_backup_tail);
3932 
3933 	/*
3934 	 * Walk the backup copy of the local descriptor ring and
3935 	 * cancel all the outstanding transactions.
3936 	 */
3937 	b_idx = vdcp->local_dring_backup_tail;
3938 	for (count = 0; count < vdcp->local_dring_backup_len; count++) {
3939 
3940 		ldep = &(vdcp->local_dring_backup[b_idx]);
3941 
3942 		/* only cancel outstanding transactions */
3943 		if (!ldep->is_free) {
3944 
3945 			DMSG(vdcp, 1, "cancelling entry idx=%x\n", b_idx);
3946 			cancelled++;
3947 
3948 			/*
3949 			 * All requests have already been cleared from the
3950 			 * local descriptor ring and the LDC channel has been
3951 			 * reset so we will never get any reply for these
3952 			 * requests. Now we just have to notify threads waiting
3953 			 * for replies that the request has failed.
3954 			 */
3955 			switch (ldep->cb_type) {
3956 			case CB_SYNC:
3957 				ASSERT(vdcp->sync_op_pending);
3958 				vdcp->sync_op_status = EIO;
3959 				vdcp->sync_op_pending = B_FALSE;
3960 				cv_signal(&vdcp->sync_pending_cv);
3961 				break;
3962 
3963 			case CB_STRATEGY:
3964 				bufp = ldep->cb_arg;
3965 				ASSERT(bufp != NULL);
3966 				bufp->b_resid = bufp->b_bcount;
3967 				VD_UPDATE_ERR_STATS(vdcp, vd_softerrs);
3968 				VD_KSTAT_RUNQ_EXIT(vdcp);
3969 				DTRACE_IO1(done, buf_t *, bufp);
3970 				bioerror(bufp, EIO);
3971 				biodone(bufp);
3972 				break;
3973 
3974 			default:
3975 				ASSERT(0);
3976 			}
3977 
3978 		}
3979 
3980 		/* get the next element to cancel */
3981 		if (++b_idx >= vdcp->local_dring_backup_len)
3982 			b_idx = 0;
3983 	}
3984 
3985 	/* all done - now clear up pending dring copy */
3986 	dring_size = vdcp->local_dring_backup_len *
3987 	    sizeof (vdcp->local_dring_backup[0]);
3988 
3989 	(void) kmem_free(vdcp->local_dring_backup, dring_size);
3990 
3991 	vdcp->local_dring_backup = NULL;
3992 
3993 	DTRACE_PROBE2(cancelled, int, cancelled, vdc_t *, vdcp);
3994 }
3995 
3996 /*
3997  * Function:
3998  *	vdc_connection_timeout
3999  *
4000  * Description:
4001  *	This function is invoked if the timeout set to establish the connection
4002  *	with vds expires. This will happen if we spend too much time in the
4003  *	VDC_STATE_INIT_WAITING or VDC_STATE_NEGOTIATE states. Then we will
4004  *	cancel any pending request and mark them as failed.
4005  *
4006  *	If the timeout does not expire, it will be cancelled when we reach the
4007  *	VDC_STATE_HANDLE_PENDING or VDC_STATE_RESETTING state. This function can
4008  *	be invoked while we are in the VDC_STATE_HANDLE_PENDING or
4009  *	VDC_STATE_RESETTING state in which case we do nothing because the
4010  *	timeout is being cancelled.
4011  *
4012  * Arguments:
4013  *	arg	- argument of the timeout function actually a soft state
4014  *		  pointer for the instance of the device driver.
4015  *
4016  * Return Code:
4017  *	None
4018  */
4019 void
4020 vdc_connection_timeout(void *arg)
4021 {
4022 	vdc_t 		*vdcp = (vdc_t *)arg;
4023 
4024 	mutex_enter(&vdcp->lock);
4025 
4026 	if (vdcp->state == VDC_STATE_HANDLE_PENDING ||
4027 	    vdcp->state == VDC_STATE_DETACH) {
4028 		/*
4029 		 * The connection has just been re-established or
4030 		 * we are detaching.
4031 		 */
4032 		vdcp->ctimeout_reached = B_FALSE;
4033 		mutex_exit(&vdcp->lock);
4034 		return;
4035 	}
4036 
4037 	vdcp->ctimeout_reached = B_TRUE;
4038 
4039 	/* notify requests waiting for sending */
4040 	cv_broadcast(&vdcp->running_cv);
4041 
4042 	/* cancel requests waiting for a result */
4043 	vdc_cancel_backup_dring(vdcp);
4044 
4045 	mutex_exit(&vdcp->lock);
4046 
4047 	cmn_err(CE_NOTE, "[%d] connection to service domain timeout",
4048 	    vdcp->instance);
4049 }
4050 
4051 /*
4052  * Function:
4053  *	vdc_backup_local_dring()
4054  *
4055  * Description:
4056  *	Backup the current dring in the event of a reset. The Dring
4057  *	transactions will be resubmitted to the server when the
4058  *	connection is restored.
4059  *
4060  * Arguments:
4061  *	vdcp	- soft state pointer for this instance of the device driver.
4062  *
4063  * Return Code:
4064  *	NONE
4065  */
4066 static void
4067 vdc_backup_local_dring(vdc_t *vdcp)
4068 {
4069 	int dring_size;
4070 
4071 	ASSERT(MUTEX_HELD(&vdcp->lock));
4072 	ASSERT(vdcp->state == VDC_STATE_RESETTING);
4073 
4074 	/*
4075 	 * If the backup dring is stil around, it means
4076 	 * that the last restore did not complete. However,
4077 	 * since we never got back into the running state,
4078 	 * the backup copy we have is still valid.
4079 	 */
4080 	if (vdcp->local_dring_backup != NULL) {
4081 		DMSG(vdcp, 1, "reusing local descriptor ring backup "
4082 		    "(len=%d, tail=%d)\n", vdcp->local_dring_backup_len,
4083 		    vdcp->local_dring_backup_tail);
4084 		return;
4085 	}
4086 
4087 	/*
4088 	 * The backup dring can be NULL and the local dring may not be
4089 	 * initialized. This can happen if we had a reset while establishing
4090 	 * a new connection but after the connection has timed out. In that
4091 	 * case the backup dring is NULL because the requests have been
4092 	 * cancelled and the request occured before the local dring is
4093 	 * initialized.
4094 	 */
4095 	if (!(vdcp->initialized & VDC_DRING_LOCAL))
4096 		return;
4097 
4098 	DMSG(vdcp, 1, "backing up the local descriptor ring (len=%d, "
4099 	    "tail=%d)\n", vdcp->dring_len, vdcp->dring_curr_idx);
4100 
4101 	dring_size = vdcp->dring_len * sizeof (vdcp->local_dring[0]);
4102 
4103 	vdcp->local_dring_backup = kmem_alloc(dring_size, KM_SLEEP);
4104 	bcopy(vdcp->local_dring, vdcp->local_dring_backup, dring_size);
4105 
4106 	vdcp->local_dring_backup_tail = vdcp->dring_curr_idx;
4107 	vdcp->local_dring_backup_len = vdcp->dring_len;
4108 }
4109 
4110 static void
4111 vdc_switch_server(vdc_t *vdcp)
4112 {
4113 	int		rv;
4114 	vdc_server_t 	*curr_server, *new_server;
4115 
4116 	ASSERT(MUTEX_HELD(&vdcp->lock));
4117 
4118 	/* if there is only one server return back */
4119 	if (vdcp->num_servers == 1) {
4120 		return;
4121 	}
4122 
4123 	/* Get current and next server */
4124 	curr_server = vdcp->curr_server;
4125 	new_server =
4126 	    (curr_server->next) ? curr_server->next : vdcp->server_list;
4127 	ASSERT(curr_server != new_server);
4128 
4129 	/* bring current server's channel down */
4130 	rv = ldc_down(curr_server->ldc_handle);
4131 	if (rv) {
4132 		DMSG(vdcp, 0, "[%d] Cannot bring channel down, port %ld\n",
4133 		    vdcp->instance, curr_server->id);
4134 		return;
4135 	}
4136 
4137 	/* switch the server */
4138 	vdcp->curr_server = new_server;
4139 
4140 	DMSG(vdcp, 0, "[%d] Switched to next vdisk server, port@%ld, ldc@%ld\n",
4141 	    vdcp->instance, vdcp->curr_server->id, vdcp->curr_server->ldc_id);
4142 }
4143 
4144 /* -------------------------------------------------------------------------- */
4145 
4146 /*
4147  * The following functions process the incoming messages from vds
4148  */
4149 
4150 /*
4151  * Function:
4152  *      vdc_process_msg_thread()
4153  *
4154  * Description:
4155  *
4156  *	Main VDC message processing thread. Each vDisk instance
4157  * 	consists of a copy of this thread. This thread triggers
4158  * 	all the handshakes and data exchange with the server. It
4159  * 	also handles all channel resets
4160  *
4161  * Arguments:
4162  *      vdc     - soft state pointer for this instance of the device driver.
4163  *
4164  * Return Code:
4165  *      None
4166  */
4167 static void
4168 vdc_process_msg_thread(vdc_t *vdcp)
4169 {
4170 	int		status;
4171 	int		ctimeout;
4172 	timeout_id_t	tmid = 0;
4173 	clock_t		ldcup_timeout = 0;
4174 
4175 	mutex_enter(&vdcp->lock);
4176 
4177 	for (;;) {
4178 
4179 #define	Q(_s)	(vdcp->state == _s) ? #_s :
4180 		DMSG(vdcp, 3, "state = %d (%s)\n", vdcp->state,
4181 		    Q(VDC_STATE_INIT)
4182 		    Q(VDC_STATE_INIT_WAITING)
4183 		    Q(VDC_STATE_NEGOTIATE)
4184 		    Q(VDC_STATE_HANDLE_PENDING)
4185 		    Q(VDC_STATE_RUNNING)
4186 		    Q(VDC_STATE_RESETTING)
4187 		    Q(VDC_STATE_DETACH)
4188 		    "UNKNOWN");
4189 
4190 		switch (vdcp->state) {
4191 		case VDC_STATE_INIT:
4192 
4193 			/*
4194 			 * If requested, start a timeout to check if the
4195 			 * connection with vds is established in the
4196 			 * specified delay. If the timeout expires, we
4197 			 * will cancel any pending request.
4198 			 *
4199 			 * If some reset have occurred while establishing
4200 			 * the connection, we already have a timeout armed
4201 			 * and in that case we don't need to arm a new one.
4202 			 *
4203 			 * The same rule applies when there are multiple vds'.
4204 			 * If either a connection cannot be established or
4205 			 * the handshake times out, the connection thread will
4206 			 * try another server. The 'ctimeout' will report
4207 			 * back an error after it expires irrespective of
4208 			 * whether the vdisk is trying to connect to just
4209 			 * one or multiple servers.
4210 			 */
4211 			ctimeout = (vdc_timeout != 0)?
4212 			    vdc_timeout : vdcp->curr_server->ctimeout;
4213 
4214 			if (ctimeout != 0 && tmid == 0) {
4215 				tmid = timeout(vdc_connection_timeout, vdcp,
4216 				    ctimeout * drv_usectohz(MICROSEC));
4217 			}
4218 
4219 			/* Check if we are re-initializing repeatedly */
4220 			if (vdcp->hshake_cnt > vdc_hshake_retries &&
4221 			    vdcp->lifecycle != VDC_LC_ONLINE) {
4222 
4223 				DMSG(vdcp, 0, "[%d] too many handshakes,cnt=%d",
4224 				    vdcp->instance, vdcp->hshake_cnt);
4225 				cmn_err(CE_NOTE, "[%d] disk access failed.\n",
4226 				    vdcp->instance);
4227 				vdcp->state = VDC_STATE_DETACH;
4228 				break;
4229 			}
4230 
4231 			/* Switch to STATE_DETACH if drv is detaching */
4232 			if (vdcp->lifecycle == VDC_LC_DETACHING) {
4233 				vdcp->state = VDC_STATE_DETACH;
4234 				break;
4235 			}
4236 
4237 			/* Switch server */
4238 			if (vdcp->hshake_cnt > 0)
4239 				vdc_switch_server(vdcp);
4240 			vdcp->hshake_cnt++;
4241 
4242 			/* Bring up connection with vds via LDC */
4243 			status = vdc_start_ldc_connection(vdcp);
4244 			if (status != EINVAL) {
4245 				vdcp->state = VDC_STATE_INIT_WAITING;
4246 			}
4247 			break;
4248 
4249 		case VDC_STATE_INIT_WAITING:
4250 
4251 			/* if channel is UP, start negotiation */
4252 			if (vdcp->curr_server->ldc_state == LDC_UP) {
4253 				vdcp->state = VDC_STATE_NEGOTIATE;
4254 				break;
4255 			}
4256 
4257 			/* check if only one server exists */
4258 			if (vdcp->num_servers == 1) {
4259 				cv_wait(&vdcp->initwait_cv, &vdcp->lock);
4260 			} else {
4261 				/*
4262 				 * wait for LDC_UP, if it times out, switch
4263 				 * to another server.
4264 				 */
4265 				ldcup_timeout = ddi_get_lbolt() +
4266 				    (vdc_ldcup_timeout *
4267 				    drv_usectohz(MICROSEC));
4268 				status = cv_timedwait(&vdcp->initwait_cv,
4269 				    &vdcp->lock, ldcup_timeout);
4270 				if (status == -1 &&
4271 				    vdcp->state == VDC_STATE_INIT_WAITING &&
4272 				    vdcp->curr_server->ldc_state != LDC_UP) {
4273 					/* timed out & still waiting */
4274 					vdcp->state = VDC_STATE_INIT;
4275 					break;
4276 				}
4277 			}
4278 
4279 			if (vdcp->state != VDC_STATE_INIT_WAITING) {
4280 				DMSG(vdcp, 0,
4281 				    "state moved to %d out from under us...\n",
4282 				    vdcp->state);
4283 			}
4284 			break;
4285 
4286 		case VDC_STATE_NEGOTIATE:
4287 			switch (status = vdc_ver_negotiation(vdcp)) {
4288 			case 0:
4289 				break;
4290 			default:
4291 				DMSG(vdcp, 0, "ver negotiate failed (%d)..\n",
4292 				    status);
4293 				goto reset;
4294 			}
4295 
4296 			switch (status = vdc_attr_negotiation(vdcp)) {
4297 			case 0:
4298 				break;
4299 			default:
4300 				DMSG(vdcp, 0, "attr negotiate failed (%d)..\n",
4301 				    status);
4302 				goto reset;
4303 			}
4304 
4305 			switch (status = vdc_dring_negotiation(vdcp)) {
4306 			case 0:
4307 				break;
4308 			default:
4309 				DMSG(vdcp, 0, "dring negotiate failed (%d)..\n",
4310 				    status);
4311 				goto reset;
4312 			}
4313 
4314 			switch (status = vdc_rdx_exchange(vdcp)) {
4315 			case 0:
4316 				vdcp->state = VDC_STATE_HANDLE_PENDING;
4317 				goto done;
4318 			default:
4319 				DMSG(vdcp, 0, "RDX xchg failed ..(%d)\n",
4320 				    status);
4321 				goto reset;
4322 			}
4323 reset:
4324 			DMSG(vdcp, 0, "negotiation failed: resetting (%d)\n",
4325 			    status);
4326 			vdcp->state = VDC_STATE_RESETTING;
4327 			vdcp->self_reset = B_TRUE;
4328 done:
4329 			DMSG(vdcp, 0, "negotiation complete (state=0x%x)...\n",
4330 			    vdcp->state);
4331 			break;
4332 
4333 		case VDC_STATE_HANDLE_PENDING:
4334 
4335 			if (vdcp->ctimeout_reached) {
4336 				/*
4337 				 * The connection timeout had been reached so
4338 				 * pending requests have been cancelled. Now
4339 				 * that the connection is back we can reset
4340 				 * the timeout.
4341 				 */
4342 				ASSERT(vdcp->local_dring_backup == NULL);
4343 				ASSERT(tmid != 0);
4344 				tmid = 0;
4345 				vdcp->ctimeout_reached = B_FALSE;
4346 				vdcp->state = VDC_STATE_RUNNING;
4347 				DMSG(vdcp, 0, "[%d] connection to service "
4348 				    "domain is up", vdcp->instance);
4349 				break;
4350 			}
4351 
4352 			mutex_exit(&vdcp->lock);
4353 			if (tmid != 0) {
4354 				(void) untimeout(tmid);
4355 				tmid = 0;
4356 			}
4357 			status = vdc_resubmit_backup_dring(vdcp);
4358 			mutex_enter(&vdcp->lock);
4359 
4360 			if (status)
4361 				vdcp->state = VDC_STATE_RESETTING;
4362 			else
4363 				vdcp->state = VDC_STATE_RUNNING;
4364 
4365 			break;
4366 
4367 		/* enter running state */
4368 		case VDC_STATE_RUNNING:
4369 			/*
4370 			 * Signal anyone waiting for the connection
4371 			 * to come on line.
4372 			 */
4373 			vdcp->hshake_cnt = 0;
4374 			cv_broadcast(&vdcp->running_cv);
4375 
4376 			/* failfast has to been checked after reset */
4377 			cv_signal(&vdcp->failfast_cv);
4378 
4379 			/* ownership is lost during reset */
4380 			if (vdcp->ownership & VDC_OWNERSHIP_WANTED)
4381 				vdcp->ownership |= VDC_OWNERSHIP_RESET;
4382 			cv_signal(&vdcp->ownership_cv);
4383 
4384 			cmn_err(CE_CONT, "?vdisk@%d is online using "
4385 			    "ldc@%ld,%ld\n", vdcp->instance,
4386 			    vdcp->curr_server->ldc_id, vdcp->curr_server->id);
4387 
4388 			mutex_exit(&vdcp->lock);
4389 
4390 			for (;;) {
4391 				vio_msg_t msg;
4392 				status = vdc_wait_for_response(vdcp, &msg);
4393 				if (status) break;
4394 
4395 				DMSG(vdcp, 1, "[%d] new pkt(s) available\n",
4396 				    vdcp->instance);
4397 				status = vdc_process_data_msg(vdcp, &msg);
4398 				if (status) {
4399 					DMSG(vdcp, 1, "[%d] process_data_msg "
4400 					    "returned err=%d\n", vdcp->instance,
4401 					    status);
4402 					break;
4403 				}
4404 
4405 			}
4406 
4407 			mutex_enter(&vdcp->lock);
4408 
4409 			cmn_err(CE_CONT, "?vdisk@%d is offline\n",
4410 			    vdcp->instance);
4411 
4412 			vdcp->state = VDC_STATE_RESETTING;
4413 			vdcp->self_reset = B_TRUE;
4414 			break;
4415 
4416 		case VDC_STATE_RESETTING:
4417 			/*
4418 			 * When we reach this state, we either come from the
4419 			 * VDC_STATE_RUNNING state and we can have pending
4420 			 * request but no timeout is armed; or we come from
4421 			 * the VDC_STATE_INIT_WAITING, VDC_NEGOTIATE or
4422 			 * VDC_HANDLE_PENDING state and there is no pending
4423 			 * request or pending requests have already been copied
4424 			 * into the backup dring. So we can safely keep the
4425 			 * connection timeout armed while we are in this state.
4426 			 */
4427 
4428 			DMSG(vdcp, 0, "Initiating channel reset "
4429 			    "(pending = %d)\n", (int)vdcp->threads_pending);
4430 
4431 			if (vdcp->self_reset) {
4432 				DMSG(vdcp, 0,
4433 				    "[%d] calling stop_ldc_connection.\n",
4434 				    vdcp->instance);
4435 				status = vdc_stop_ldc_connection(vdcp);
4436 				vdcp->self_reset = B_FALSE;
4437 			}
4438 
4439 			/*
4440 			 * Wait for all threads currently waiting
4441 			 * for a free dring entry to use.
4442 			 */
4443 			while (vdcp->threads_pending) {
4444 				cv_broadcast(&vdcp->membind_cv);
4445 				cv_broadcast(&vdcp->dring_free_cv);
4446 				mutex_exit(&vdcp->lock);
4447 				/* give the waiters enough time to wake up */
4448 				delay(vdc_hz_min_ldc_delay);
4449 				mutex_enter(&vdcp->lock);
4450 			}
4451 
4452 			ASSERT(vdcp->threads_pending == 0);
4453 
4454 			/* Sanity check that no thread is receiving */
4455 			ASSERT(vdcp->read_state != VDC_READ_WAITING);
4456 
4457 			vdcp->read_state = VDC_READ_IDLE;
4458 
4459 			vdc_backup_local_dring(vdcp);
4460 
4461 			/* cleanup the old d-ring */
4462 			vdc_destroy_descriptor_ring(vdcp);
4463 
4464 			/* go and start again */
4465 			vdcp->state = VDC_STATE_INIT;
4466 
4467 			break;
4468 
4469 		case VDC_STATE_DETACH:
4470 			DMSG(vdcp, 0, "[%d] Reset thread exit cleanup ..\n",
4471 			    vdcp->instance);
4472 
4473 			/* cancel any pending timeout */
4474 			mutex_exit(&vdcp->lock);
4475 			if (tmid != 0) {
4476 				(void) untimeout(tmid);
4477 				tmid = 0;
4478 			}
4479 			mutex_enter(&vdcp->lock);
4480 
4481 			/*
4482 			 * Signal anyone waiting for connection
4483 			 * to come online
4484 			 */
4485 			cv_broadcast(&vdcp->running_cv);
4486 
4487 			while (vdcp->sync_op_pending) {
4488 				cv_signal(&vdcp->sync_pending_cv);
4489 				cv_signal(&vdcp->sync_blocked_cv);
4490 				mutex_exit(&vdcp->lock);
4491 				/* give the waiters enough time to wake up */
4492 				delay(vdc_hz_min_ldc_delay);
4493 				mutex_enter(&vdcp->lock);
4494 			}
4495 
4496 			mutex_exit(&vdcp->lock);
4497 
4498 			DMSG(vdcp, 0, "[%d] Msg processing thread exiting ..\n",
4499 			    vdcp->instance);
4500 			thread_exit();
4501 			break;
4502 		}
4503 	}
4504 }
4505 
4506 
4507 /*
4508  * Function:
4509  *	vdc_process_data_msg()
4510  *
4511  * Description:
4512  *	This function is called by the message processing thread each time
4513  *	a message with a msgtype of VIO_TYPE_DATA is received. It will either
4514  *	be an ACK or NACK from vds[1] which vdc handles as follows.
4515  *		ACK	- wake up the waiting thread
4516  *		NACK	- resend any messages necessary
4517  *
4518  *	[1] Although the message format allows it, vds should not send a
4519  *	    VIO_SUBTYPE_INFO message to vdc asking it to read data; if for
4520  *	    some bizarre reason it does, vdc will reset the connection.
4521  *
4522  * Arguments:
4523  *	vdc	- soft state pointer for this instance of the device driver.
4524  *	msg	- the LDC message sent by vds
4525  *
4526  * Return Code:
4527  *	0	- Success.
4528  *	> 0	- error value returned by LDC
4529  */
4530 static int
4531 vdc_process_data_msg(vdc_t *vdcp, vio_msg_t *msg)
4532 {
4533 	int			status = 0;
4534 	vio_dring_msg_t		*dring_msg;
4535 	vdc_local_desc_t	*ldep = NULL;
4536 	int			start, end;
4537 	int			idx;
4538 	int			op;
4539 
4540 	dring_msg = (vio_dring_msg_t *)msg;
4541 
4542 	ASSERT(msg->tag.vio_msgtype == VIO_TYPE_DATA);
4543 	ASSERT(vdcp != NULL);
4544 
4545 	mutex_enter(&vdcp->lock);
4546 
4547 	/*
4548 	 * Check to see if the message has bogus data
4549 	 */
4550 	idx = start = dring_msg->start_idx;
4551 	end = dring_msg->end_idx;
4552 	if ((start >= vdcp->dring_len) ||
4553 	    (end >= vdcp->dring_len) || (end < -1)) {
4554 		/*
4555 		 * Update the I/O statistics to indicate that an error ocurred.
4556 		 * No need to update the wait/run queues as no specific read or
4557 		 * write request is being completed in response to this 'msg'.
4558 		 */
4559 		VD_UPDATE_ERR_STATS(vdcp, vd_softerrs);
4560 		DMSG(vdcp, 0, "[%d] Bogus ACK data : start %d, end %d\n",
4561 		    vdcp->instance, start, end);
4562 		mutex_exit(&vdcp->lock);
4563 		return (EINVAL);
4564 	}
4565 
4566 	/*
4567 	 * Verify that the sequence number is what vdc expects.
4568 	 */
4569 	switch (vdc_verify_seq_num(vdcp, dring_msg)) {
4570 	case VDC_SEQ_NUM_TODO:
4571 		break;	/* keep processing this message */
4572 	case VDC_SEQ_NUM_SKIP:
4573 		mutex_exit(&vdcp->lock);
4574 		return (0);
4575 	case VDC_SEQ_NUM_INVALID:
4576 		/*
4577 		 * Update the I/O statistics to indicate that an error ocurred.
4578 		 * No need to update the wait/run queues as no specific read or
4579 		 * write request is being completed in response to this 'msg'.
4580 		 */
4581 		VD_UPDATE_ERR_STATS(vdcp, vd_softerrs);
4582 		DMSG(vdcp, 0, "[%d] invalid seqno\n", vdcp->instance);
4583 		mutex_exit(&vdcp->lock);
4584 		return (ENXIO);
4585 	}
4586 
4587 	if (msg->tag.vio_subtype == VIO_SUBTYPE_NACK) {
4588 		/*
4589 		 * Update the I/O statistics to indicate that an error ocurred.
4590 		 *
4591 		 * We need to update the run queue if a read or write request
4592 		 * is being NACKed - otherwise there will appear to be an
4593 		 * indefinite outstanding request and statistics reported by
4594 		 * iostat(1M) will be incorrect. The transaction will be
4595 		 * resubmitted from the backup DRing following the reset
4596 		 * and the wait/run queues will be entered again.
4597 		 */
4598 		ldep = &vdcp->local_dring[idx];
4599 		op = ldep->operation;
4600 		if ((op == VD_OP_BREAD) || (op == VD_OP_BWRITE)) {
4601 			DTRACE_IO1(done, buf_t *, ldep->cb_arg);
4602 			VD_KSTAT_RUNQ_EXIT(vdcp);
4603 		}
4604 		VD_UPDATE_ERR_STATS(vdcp, vd_softerrs);
4605 		VDC_DUMP_DRING_MSG(dring_msg);
4606 		DMSG(vdcp, 0, "[%d] DATA NACK\n", vdcp->instance);
4607 		mutex_exit(&vdcp->lock);
4608 		return (EIO);
4609 
4610 	} else if (msg->tag.vio_subtype == VIO_SUBTYPE_INFO) {
4611 		/*
4612 		 * Update the I/O statistics to indicate that an error occurred.
4613 		 * No need to update the wait/run queues as no specific read or
4614 		 * write request is being completed in response to this 'msg'.
4615 		 */
4616 		VD_UPDATE_ERR_STATS(vdcp, vd_protoerrs);
4617 		mutex_exit(&vdcp->lock);
4618 		return (EPROTO);
4619 	}
4620 
4621 	DMSG(vdcp, 1, ": start %d end %d\n", start, end);
4622 	ASSERT(start == end);
4623 
4624 	ldep = &vdcp->local_dring[idx];
4625 
4626 	DMSG(vdcp, 1, ": state 0x%x - cb_type 0x%x\n",
4627 	    ldep->dep->hdr.dstate, ldep->cb_type);
4628 
4629 	if (ldep->dep->hdr.dstate == VIO_DESC_DONE) {
4630 		struct buf *bufp;
4631 
4632 		switch (ldep->cb_type) {
4633 		case CB_SYNC:
4634 			ASSERT(vdcp->sync_op_pending);
4635 
4636 			status = vdc_depopulate_descriptor(vdcp, idx);
4637 			vdcp->sync_op_status = status;
4638 			vdcp->sync_op_pending = B_FALSE;
4639 			cv_signal(&vdcp->sync_pending_cv);
4640 			break;
4641 
4642 		case CB_STRATEGY:
4643 			bufp = ldep->cb_arg;
4644 			ASSERT(bufp != NULL);
4645 			bufp->b_resid =
4646 			    bufp->b_bcount - ldep->dep->payload.nbytes;
4647 			status = ldep->dep->payload.status; /* Future:ntoh */
4648 			if (status != 0) {
4649 				DMSG(vdcp, 1, "strategy status=%d\n", status);
4650 				VD_UPDATE_ERR_STATS(vdcp, vd_softerrs);
4651 				bioerror(bufp, status);
4652 			}
4653 
4654 			(void) vdc_depopulate_descriptor(vdcp, idx);
4655 
4656 			DMSG(vdcp, 1,
4657 			    "strategy complete req=%ld bytes resp=%ld bytes\n",
4658 			    bufp->b_bcount, ldep->dep->payload.nbytes);
4659 
4660 			if (status != 0 && vdcp->failfast_interval != 0) {
4661 				/*
4662 				 * The I/O has failed and failfast is enabled.
4663 				 * We need the failfast thread to check if the
4664 				 * failure is due to a reservation conflict.
4665 				 */
4666 				(void) vdc_failfast_io_queue(vdcp, bufp);
4667 			} else {
4668 				if (status == 0) {
4669 					op = (bufp->b_flags & B_READ) ?
4670 					    VD_OP_BREAD : VD_OP_BWRITE;
4671 					VD_UPDATE_IO_STATS(vdcp, op,
4672 					    ldep->dep->payload.nbytes);
4673 				}
4674 				VD_KSTAT_RUNQ_EXIT(vdcp);
4675 				DTRACE_IO1(done, buf_t *, bufp);
4676 				biodone(bufp);
4677 			}
4678 			break;
4679 
4680 		default:
4681 			ASSERT(0);
4682 		}
4683 	}
4684 
4685 	/* let the arrival signal propogate */
4686 	mutex_exit(&vdcp->lock);
4687 
4688 	/* probe gives the count of how many entries were processed */
4689 	DTRACE_PROBE2(processed, int, 1, vdc_t *, vdcp);
4690 
4691 	return (0);
4692 }
4693 
4694 
4695 /*
4696  * Function:
4697  *	vdc_handle_ver_msg()
4698  *
4699  * Description:
4700  *
4701  * Arguments:
4702  *	vdc	- soft state pointer for this instance of the device driver.
4703  *	ver_msg	- LDC message sent by vDisk server
4704  *
4705  * Return Code:
4706  *	0	- Success
4707  */
4708 static int
4709 vdc_handle_ver_msg(vdc_t *vdc, vio_ver_msg_t *ver_msg)
4710 {
4711 	int status = 0;
4712 
4713 	ASSERT(vdc != NULL);
4714 	ASSERT(mutex_owned(&vdc->lock));
4715 
4716 	if (ver_msg->tag.vio_subtype_env != VIO_VER_INFO) {
4717 		return (EPROTO);
4718 	}
4719 
4720 	if (ver_msg->dev_class != VDEV_DISK_SERVER) {
4721 		return (EINVAL);
4722 	}
4723 
4724 	switch (ver_msg->tag.vio_subtype) {
4725 	case VIO_SUBTYPE_ACK:
4726 		/*
4727 		 * We check to see if the version returned is indeed supported
4728 		 * (The server may have also adjusted the minor number downwards
4729 		 * and if so 'ver_msg' will contain the actual version agreed)
4730 		 */
4731 		if (vdc_is_supported_version(ver_msg)) {
4732 			vdc->ver.major = ver_msg->ver_major;
4733 			vdc->ver.minor = ver_msg->ver_minor;
4734 			ASSERT(vdc->ver.major > 0);
4735 		} else {
4736 			status = EPROTO;
4737 		}
4738 		break;
4739 
4740 	case VIO_SUBTYPE_NACK:
4741 		/*
4742 		 * call vdc_is_supported_version() which will return the next
4743 		 * supported version (if any) in 'ver_msg'
4744 		 */
4745 		(void) vdc_is_supported_version(ver_msg);
4746 		if (ver_msg->ver_major > 0) {
4747 			size_t len = sizeof (*ver_msg);
4748 
4749 			ASSERT(vdc->ver.major > 0);
4750 
4751 			/* reset the necessary fields and resend */
4752 			ver_msg->tag.vio_subtype = VIO_SUBTYPE_INFO;
4753 			ver_msg->dev_class = VDEV_DISK;
4754 
4755 			status = vdc_send(vdc, (caddr_t)ver_msg, &len);
4756 			DMSG(vdc, 0, "[%d] Resend VER info (LDC status = %d)\n",
4757 			    vdc->instance, status);
4758 			if (len != sizeof (*ver_msg))
4759 				status = EBADMSG;
4760 		} else {
4761 			DMSG(vdc, 0, "[%d] No common version with vDisk server",
4762 			    vdc->instance);
4763 			status = ENOTSUP;
4764 		}
4765 
4766 		break;
4767 	case VIO_SUBTYPE_INFO:
4768 		/*
4769 		 * Handle the case where vds starts handshake
4770 		 * (for now only vdc is the instigator)
4771 		 */
4772 		status = ENOTSUP;
4773 		break;
4774 
4775 	default:
4776 		status = EINVAL;
4777 		break;
4778 	}
4779 
4780 	return (status);
4781 }
4782 
4783 /*
4784  * Function:
4785  *	vdc_handle_attr_msg()
4786  *
4787  * Description:
4788  *
4789  * Arguments:
4790  *	vdc	- soft state pointer for this instance of the device driver.
4791  *	attr_msg	- LDC message sent by vDisk server
4792  *
4793  * Return Code:
4794  *	0	- Success
4795  */
4796 static int
4797 vdc_handle_attr_msg(vdc_t *vdc, vd_attr_msg_t *attr_msg)
4798 {
4799 	int status = 0;
4800 
4801 	ASSERT(vdc != NULL);
4802 	ASSERT(mutex_owned(&vdc->lock));
4803 
4804 	if (attr_msg->tag.vio_subtype_env != VIO_ATTR_INFO) {
4805 		return (EPROTO);
4806 	}
4807 
4808 	switch (attr_msg->tag.vio_subtype) {
4809 	case VIO_SUBTYPE_ACK:
4810 		/*
4811 		 * We now verify the attributes sent by vds.
4812 		 */
4813 		if (attr_msg->vdisk_size == 0) {
4814 			DMSG(vdc, 0, "[%d] Invalid disk size from vds",
4815 			    vdc->instance);
4816 			status = EINVAL;
4817 			break;
4818 		}
4819 
4820 		if (attr_msg->max_xfer_sz == 0) {
4821 			DMSG(vdc, 0, "[%d] Invalid transfer size from vds",
4822 			    vdc->instance);
4823 			status = EINVAL;
4824 			break;
4825 		}
4826 
4827 		if (attr_msg->vdisk_size == VD_SIZE_UNKNOWN) {
4828 			DMSG(vdc, 0, "[%d] Unknown disk size from vds",
4829 			    vdc->instance);
4830 			attr_msg->vdisk_size = 0;
4831 		}
4832 		/* update disk, block and transfer sizes */
4833 		vdc_update_size(vdc, attr_msg->vdisk_size,
4834 		    attr_msg->vdisk_block_size, attr_msg->max_xfer_sz);
4835 		vdc->vdisk_type = attr_msg->vdisk_type;
4836 		vdc->operations = attr_msg->operations;
4837 		if (vio_ver_is_supported(vdc->ver, 1, 1))
4838 			vdc->vdisk_media = attr_msg->vdisk_media;
4839 		else
4840 			vdc->vdisk_media = 0;
4841 
4842 		DMSG(vdc, 0, "[%d] max_xfer_sz: sent %lx acked %lx\n",
4843 		    vdc->instance, vdc->max_xfer_sz, attr_msg->max_xfer_sz);
4844 		DMSG(vdc, 0, "[%d] vdisk_block_size: sent %lx acked %x\n",
4845 		    vdc->instance, vdc->block_size,
4846 		    attr_msg->vdisk_block_size);
4847 
4848 		if ((attr_msg->xfer_mode != VIO_DRING_MODE_V1_0) ||
4849 		    (attr_msg->vdisk_size > INT64_MAX) ||
4850 		    (attr_msg->operations == 0) ||
4851 		    (attr_msg->vdisk_type > VD_DISK_TYPE_DISK)) {
4852 			DMSG(vdc, 0, "[%d] Invalid attributes from vds",
4853 			    vdc->instance);
4854 			status = EINVAL;
4855 			break;
4856 		}
4857 
4858 		/*
4859 		 * Now that we have received all attributes we can create a
4860 		 * fake geometry for the disk.
4861 		 */
4862 		vdc_create_fake_geometry(vdc);
4863 		break;
4864 
4865 	case VIO_SUBTYPE_NACK:
4866 		/*
4867 		 * vds could not handle the attributes we sent so we
4868 		 * stop negotiating.
4869 		 */
4870 		status = EPROTO;
4871 		break;
4872 
4873 	case VIO_SUBTYPE_INFO:
4874 		/*
4875 		 * Handle the case where vds starts the handshake
4876 		 * (for now; vdc is the only supported instigatior)
4877 		 */
4878 		status = ENOTSUP;
4879 		break;
4880 
4881 	default:
4882 		status = ENOTSUP;
4883 		break;
4884 	}
4885 
4886 	return (status);
4887 }
4888 
4889 /*
4890  * Function:
4891  *	vdc_handle_dring_reg_msg()
4892  *
4893  * Description:
4894  *
4895  * Arguments:
4896  *	vdc		- soft state pointer for this instance of the driver.
4897  *	dring_msg	- LDC message sent by vDisk server
4898  *
4899  * Return Code:
4900  *	0	- Success
4901  */
4902 static int
4903 vdc_handle_dring_reg_msg(vdc_t *vdc, vio_dring_reg_msg_t *dring_msg)
4904 {
4905 	int		status = 0;
4906 
4907 	ASSERT(vdc != NULL);
4908 	ASSERT(mutex_owned(&vdc->lock));
4909 
4910 	if (dring_msg->tag.vio_subtype_env != VIO_DRING_REG) {
4911 		return (EPROTO);
4912 	}
4913 
4914 	switch (dring_msg->tag.vio_subtype) {
4915 	case VIO_SUBTYPE_ACK:
4916 		/* save the received dring_ident */
4917 		vdc->dring_ident = dring_msg->dring_ident;
4918 		DMSG(vdc, 0, "[%d] Received dring ident=0x%lx\n",
4919 		    vdc->instance, vdc->dring_ident);
4920 		break;
4921 
4922 	case VIO_SUBTYPE_NACK:
4923 		/*
4924 		 * vds could not handle the DRing info we sent so we
4925 		 * stop negotiating.
4926 		 */
4927 		DMSG(vdc, 0, "[%d] server could not register DRing\n",
4928 		    vdc->instance);
4929 		status = EPROTO;
4930 		break;
4931 
4932 	case VIO_SUBTYPE_INFO:
4933 		/*
4934 		 * Handle the case where vds starts handshake
4935 		 * (for now only vdc is the instigatior)
4936 		 */
4937 		status = ENOTSUP;
4938 		break;
4939 	default:
4940 		status = ENOTSUP;
4941 	}
4942 
4943 	return (status);
4944 }
4945 
4946 /*
4947  * Function:
4948  *	vdc_verify_seq_num()
4949  *
4950  * Description:
4951  *	This functions verifies that the sequence number sent back by the vDisk
4952  *	server with the latest message is what is expected (i.e. it is greater
4953  *	than the last seq num sent by the vDisk server and less than or equal
4954  *	to the last seq num generated by vdc).
4955  *
4956  *	It then checks the request ID to see if any requests need processing
4957  *	in the DRing.
4958  *
4959  * Arguments:
4960  *	vdc		- soft state pointer for this instance of the driver.
4961  *	dring_msg	- pointer to the LDC message sent by vds
4962  *
4963  * Return Code:
4964  *	VDC_SEQ_NUM_TODO	- Message needs to be processed
4965  *	VDC_SEQ_NUM_SKIP	- Message has already been processed
4966  *	VDC_SEQ_NUM_INVALID	- The seq numbers are so out of sync,
4967  *				  vdc cannot deal with them
4968  */
4969 static int
4970 vdc_verify_seq_num(vdc_t *vdc, vio_dring_msg_t *dring_msg)
4971 {
4972 	ASSERT(vdc != NULL);
4973 	ASSERT(dring_msg != NULL);
4974 	ASSERT(mutex_owned(&vdc->lock));
4975 
4976 	/*
4977 	 * Check to see if the messages were responded to in the correct
4978 	 * order by vds.
4979 	 */
4980 	if ((dring_msg->seq_num <= vdc->seq_num_reply) ||
4981 	    (dring_msg->seq_num > vdc->seq_num)) {
4982 		DMSG(vdc, 0, "?[%d] Bogus sequence_number %lu: "
4983 		    "%lu > expected <= %lu (last proc req %lu sent %lu)\n",
4984 		    vdc->instance, dring_msg->seq_num,
4985 		    vdc->seq_num_reply, vdc->seq_num,
4986 		    vdc->req_id_proc, vdc->req_id);
4987 		return (VDC_SEQ_NUM_INVALID);
4988 	}
4989 	vdc->seq_num_reply = dring_msg->seq_num;
4990 
4991 	if (vdc->req_id_proc < vdc->req_id)
4992 		return (VDC_SEQ_NUM_TODO);
4993 	else
4994 		return (VDC_SEQ_NUM_SKIP);
4995 }
4996 
4997 
4998 /*
4999  * Function:
5000  *	vdc_is_supported_version()
5001  *
5002  * Description:
5003  *	This routine checks if the major/minor version numbers specified in
5004  *	'ver_msg' are supported. If not it finds the next version that is
5005  *	in the supported version list 'vdc_version[]' and sets the fields in
5006  *	'ver_msg' to those values
5007  *
5008  * Arguments:
5009  *	ver_msg	- LDC message sent by vDisk server
5010  *
5011  * Return Code:
5012  *	B_TRUE	- Success
5013  *	B_FALSE	- Version not supported
5014  */
5015 static boolean_t
5016 vdc_is_supported_version(vio_ver_msg_t *ver_msg)
5017 {
5018 	int vdc_num_versions = sizeof (vdc_version) / sizeof (vdc_version[0]);
5019 
5020 	for (int i = 0; i < vdc_num_versions; i++) {
5021 		ASSERT(vdc_version[i].major > 0);
5022 		ASSERT((i == 0) ||
5023 		    (vdc_version[i].major < vdc_version[i-1].major));
5024 
5025 		/*
5026 		 * If the major versions match, adjust the minor version, if
5027 		 * necessary, down to the highest value supported by this
5028 		 * client. The server should support all minor versions lower
5029 		 * than the value it sent
5030 		 */
5031 		if (ver_msg->ver_major == vdc_version[i].major) {
5032 			if (ver_msg->ver_minor > vdc_version[i].minor) {
5033 				DMSGX(0,
5034 				    "Adjusting minor version from %u to %u",
5035 				    ver_msg->ver_minor, vdc_version[i].minor);
5036 				ver_msg->ver_minor = vdc_version[i].minor;
5037 			}
5038 			return (B_TRUE);
5039 		}
5040 
5041 		/*
5042 		 * If the message contains a higher major version number, set
5043 		 * the message's major/minor versions to the current values
5044 		 * and return false, so this message will get resent with
5045 		 * these values, and the server will potentially try again
5046 		 * with the same or a lower version
5047 		 */
5048 		if (ver_msg->ver_major > vdc_version[i].major) {
5049 			ver_msg->ver_major = vdc_version[i].major;
5050 			ver_msg->ver_minor = vdc_version[i].minor;
5051 			DMSGX(0, "Suggesting major/minor (0x%x/0x%x)\n",
5052 			    ver_msg->ver_major, ver_msg->ver_minor);
5053 
5054 			return (B_FALSE);
5055 		}
5056 
5057 		/*
5058 		 * Otherwise, the message's major version is less than the
5059 		 * current major version, so continue the loop to the next
5060 		 * (lower) supported version
5061 		 */
5062 	}
5063 
5064 	/*
5065 	 * No common version was found; "ground" the version pair in the
5066 	 * message to terminate negotiation
5067 	 */
5068 	ver_msg->ver_major = 0;
5069 	ver_msg->ver_minor = 0;
5070 
5071 	return (B_FALSE);
5072 }
5073 /* -------------------------------------------------------------------------- */
5074 
5075 /*
5076  * DKIO(7) support
5077  */
5078 
5079 typedef struct vdc_dk_arg {
5080 	struct dk_callback	dkc;
5081 	int			mode;
5082 	dev_t			dev;
5083 	vdc_t			*vdc;
5084 } vdc_dk_arg_t;
5085 
5086 /*
5087  * Function:
5088  * 	vdc_dkio_flush_cb()
5089  *
5090  * Description:
5091  *	This routine is a callback for DKIOCFLUSHWRITECACHE which can be called
5092  *	by kernel code.
5093  *
5094  * Arguments:
5095  *	arg	- a pointer to a vdc_dk_arg_t structure.
5096  */
5097 void
5098 vdc_dkio_flush_cb(void *arg)
5099 {
5100 	struct vdc_dk_arg	*dk_arg = (struct vdc_dk_arg *)arg;
5101 	struct dk_callback	*dkc = NULL;
5102 	vdc_t			*vdc = NULL;
5103 	int			rv;
5104 
5105 	if (dk_arg == NULL) {
5106 		cmn_err(CE_NOTE, "?[Unk] DKIOCFLUSHWRITECACHE arg is NULL\n");
5107 		return;
5108 	}
5109 	dkc = &dk_arg->dkc;
5110 	vdc = dk_arg->vdc;
5111 	ASSERT(vdc != NULL);
5112 
5113 	rv = vdc_do_sync_op(vdc, VD_OP_FLUSH, NULL, 0,
5114 	    VDCPART(dk_arg->dev), 0, CB_SYNC, 0, VIO_both_dir, B_TRUE);
5115 	if (rv != 0) {
5116 		DMSG(vdc, 0, "[%d] DKIOCFLUSHWRITECACHE failed %d : model %x\n",
5117 		    vdc->instance, rv,
5118 		    ddi_model_convert_from(dk_arg->mode & FMODELS));
5119 	}
5120 
5121 	/*
5122 	 * Trigger the call back to notify the caller the the ioctl call has
5123 	 * been completed.
5124 	 */
5125 	if ((dk_arg->mode & FKIOCTL) &&
5126 	    (dkc != NULL) &&
5127 	    (dkc->dkc_callback != NULL)) {
5128 		ASSERT(dkc->dkc_cookie != NULL);
5129 		(*dkc->dkc_callback)(dkc->dkc_cookie, rv);
5130 	}
5131 
5132 	/* Indicate that one less DKIO write flush is outstanding */
5133 	mutex_enter(&vdc->lock);
5134 	vdc->dkio_flush_pending--;
5135 	ASSERT(vdc->dkio_flush_pending >= 0);
5136 	mutex_exit(&vdc->lock);
5137 
5138 	/* free the mem that was allocated when the callback was dispatched */
5139 	kmem_free(arg, sizeof (vdc_dk_arg_t));
5140 }
5141 
5142 /*
5143  * Function:
5144  * 	vdc_dkio_gapart()
5145  *
5146  * Description:
5147  *	This function implements the DKIOCGAPART ioctl.
5148  *
5149  * Arguments:
5150  *	vdc	- soft state pointer
5151  *	arg	- a pointer to a dk_map[NDKMAP] or dk_map32[NDKMAP] structure
5152  *	flag	- ioctl flags
5153  */
5154 static int
5155 vdc_dkio_gapart(vdc_t *vdc, caddr_t arg, int flag)
5156 {
5157 	struct dk_geom *geom;
5158 	struct extvtoc *vtoc;
5159 	union {
5160 		struct dk_map map[NDKMAP];
5161 		struct dk_map32 map32[NDKMAP];
5162 	} data;
5163 	int i, rv, size;
5164 
5165 	mutex_enter(&vdc->lock);
5166 
5167 	if ((rv = vdc_validate_geometry(vdc)) != 0) {
5168 		mutex_exit(&vdc->lock);
5169 		return (rv);
5170 	}
5171 
5172 	if (vdc->vdisk_size > VD_OLDVTOC_LIMIT) {
5173 		mutex_exit(&vdc->lock);
5174 		return (EOVERFLOW);
5175 	}
5176 
5177 	vtoc = vdc->vtoc;
5178 	geom = vdc->geom;
5179 
5180 	if (ddi_model_convert_from(flag & FMODELS) == DDI_MODEL_ILP32) {
5181 
5182 		for (i = 0; i < vtoc->v_nparts; i++) {
5183 			data.map32[i].dkl_cylno = vtoc->v_part[i].p_start /
5184 			    (geom->dkg_nhead * geom->dkg_nsect);
5185 			data.map32[i].dkl_nblk = vtoc->v_part[i].p_size;
5186 		}
5187 		size = NDKMAP * sizeof (struct dk_map32);
5188 
5189 	} else {
5190 
5191 		for (i = 0; i < vtoc->v_nparts; i++) {
5192 			data.map[i].dkl_cylno = vtoc->v_part[i].p_start /
5193 			    (geom->dkg_nhead * geom->dkg_nsect);
5194 			data.map[i].dkl_nblk = vtoc->v_part[i].p_size;
5195 		}
5196 		size = NDKMAP * sizeof (struct dk_map);
5197 
5198 	}
5199 
5200 	mutex_exit(&vdc->lock);
5201 
5202 	if (ddi_copyout(&data, arg, size, flag) != 0)
5203 		return (EFAULT);
5204 
5205 	return (0);
5206 }
5207 
5208 /*
5209  * Function:
5210  * 	vdc_dkio_partition()
5211  *
5212  * Description:
5213  *	This function implements the DKIOCPARTITION ioctl.
5214  *
5215  * Arguments:
5216  *	vdc	- soft state pointer
5217  *	arg	- a pointer to a struct partition64 structure
5218  *	flag	- ioctl flags
5219  */
5220 static int
5221 vdc_dkio_partition(vdc_t *vdc, caddr_t arg, int flag)
5222 {
5223 	struct partition64 p64;
5224 	efi_gpt_t *gpt;
5225 	efi_gpe_t *gpe;
5226 	vd_efi_dev_t edev;
5227 	uint_t partno;
5228 	int rv;
5229 
5230 	if (ddi_copyin(arg, &p64, sizeof (struct partition64), flag)) {
5231 		return (EFAULT);
5232 	}
5233 
5234 	VD_EFI_DEV_SET(edev, vdc, vd_process_efi_ioctl);
5235 
5236 	if ((rv = vd_efi_alloc_and_read(&edev, &gpt, &gpe)) != 0) {
5237 		return (rv);
5238 	}
5239 
5240 	partno = p64.p_partno;
5241 
5242 	if (partno >= gpt->efi_gpt_NumberOfPartitionEntries) {
5243 		vd_efi_free(&edev, gpt, gpe);
5244 		return (ESRCH);
5245 	}
5246 
5247 	bcopy(&gpe[partno].efi_gpe_PartitionTypeGUID, &p64.p_type,
5248 	    sizeof (struct uuid));
5249 	p64.p_start = gpe[partno].efi_gpe_StartingLBA;
5250 	p64.p_size = gpe[partno].efi_gpe_EndingLBA - p64.p_start + 1;
5251 
5252 	if (ddi_copyout(&p64, arg, sizeof (struct partition64), flag)) {
5253 		vd_efi_free(&edev, gpt, gpe);
5254 		return (EFAULT);
5255 	}
5256 
5257 	vd_efi_free(&edev, gpt, gpe);
5258 	return (0);
5259 }
5260 
5261 /*
5262  * Function:
5263  * 	vdc_dioctl_rwcmd()
5264  *
5265  * Description:
5266  *	This function implements the DIOCTL_RWCMD ioctl. This ioctl is used
5267  *	for DKC_DIRECT disks to read or write at an absolute disk offset.
5268  *
5269  * Arguments:
5270  *	dev	- device
5271  *	arg	- a pointer to a dadkio_rwcmd or dadkio_rwcmd32 structure
5272  *	flag	- ioctl flags
5273  */
5274 static int
5275 vdc_dioctl_rwcmd(dev_t dev, caddr_t arg, int flag)
5276 {
5277 	struct dadkio_rwcmd32 rwcmd32;
5278 	struct dadkio_rwcmd rwcmd;
5279 	struct iovec aiov;
5280 	struct uio auio;
5281 	int rw, status;
5282 	struct buf *buf;
5283 
5284 	if (ddi_model_convert_from(flag & FMODELS) == DDI_MODEL_ILP32) {
5285 		if (ddi_copyin((caddr_t)arg, (caddr_t)&rwcmd32,
5286 		    sizeof (struct dadkio_rwcmd32), flag)) {
5287 			return (EFAULT);
5288 		}
5289 		rwcmd.cmd = rwcmd32.cmd;
5290 		rwcmd.flags = rwcmd32.flags;
5291 		rwcmd.blkaddr = (daddr_t)rwcmd32.blkaddr;
5292 		rwcmd.buflen = rwcmd32.buflen;
5293 		rwcmd.bufaddr = (caddr_t)(uintptr_t)rwcmd32.bufaddr;
5294 	} else {
5295 		if (ddi_copyin((caddr_t)arg, (caddr_t)&rwcmd,
5296 		    sizeof (struct dadkio_rwcmd), flag)) {
5297 			return (EFAULT);
5298 		}
5299 	}
5300 
5301 	switch (rwcmd.cmd) {
5302 	case DADKIO_RWCMD_READ:
5303 		rw = B_READ;
5304 		break;
5305 	case DADKIO_RWCMD_WRITE:
5306 		rw = B_WRITE;
5307 		break;
5308 	default:
5309 		return (EINVAL);
5310 	}
5311 
5312 	bzero((caddr_t)&aiov, sizeof (struct iovec));
5313 	aiov.iov_base   = rwcmd.bufaddr;
5314 	aiov.iov_len    = rwcmd.buflen;
5315 
5316 	bzero((caddr_t)&auio, sizeof (struct uio));
5317 	auio.uio_iov    = &aiov;
5318 	auio.uio_iovcnt = 1;
5319 	auio.uio_loffset = rwcmd.blkaddr * DEV_BSIZE;
5320 	auio.uio_resid  = rwcmd.buflen;
5321 	auio.uio_segflg = flag & FKIOCTL ? UIO_SYSSPACE : UIO_USERSPACE;
5322 
5323 	buf = kmem_alloc(sizeof (buf_t), KM_SLEEP);
5324 	bioinit(buf);
5325 	/*
5326 	 * We use the private field of buf to specify that this is an
5327 	 * I/O using an absolute offset.
5328 	 */
5329 	buf->b_private = (void *)VD_SLICE_NONE;
5330 
5331 	status = physio(vdc_strategy, buf, dev, rw, vdc_min, &auio);
5332 
5333 	biofini(buf);
5334 	kmem_free(buf, sizeof (buf_t));
5335 
5336 	return (status);
5337 }
5338 
5339 /*
5340  * Allocate a buffer for a VD_OP_SCSICMD operation. The size of the allocated
5341  * buffer is returned in alloc_len.
5342  */
5343 static vd_scsi_t *
5344 vdc_scsi_alloc(int cdb_len, int sense_len, int datain_len, int dataout_len,
5345     int *alloc_len)
5346 {
5347 	vd_scsi_t *vd_scsi;
5348 	int vd_scsi_len = VD_SCSI_SIZE;
5349 
5350 	vd_scsi_len += P2ROUNDUP(cdb_len, sizeof (uint64_t));
5351 	vd_scsi_len += P2ROUNDUP(sense_len, sizeof (uint64_t));
5352 	vd_scsi_len += P2ROUNDUP(datain_len, sizeof (uint64_t));
5353 	vd_scsi_len += P2ROUNDUP(dataout_len, sizeof (uint64_t));
5354 
5355 	ASSERT(vd_scsi_len % sizeof (uint64_t) == 0);
5356 
5357 	vd_scsi = kmem_zalloc(vd_scsi_len, KM_SLEEP);
5358 
5359 	vd_scsi->cdb_len = cdb_len;
5360 	vd_scsi->sense_len = sense_len;
5361 	vd_scsi->datain_len = datain_len;
5362 	vd_scsi->dataout_len = dataout_len;
5363 
5364 	*alloc_len = vd_scsi_len;
5365 
5366 	return (vd_scsi);
5367 }
5368 
5369 /*
5370  * Convert the status of a SCSI command to a Solaris return code.
5371  *
5372  * Arguments:
5373  *	vd_scsi		- The SCSI operation buffer.
5374  *	log_error	- indicate if an error message should be logged.
5375  *
5376  * Note that our SCSI error messages are rather primitive for the moment
5377  * and could be improved by decoding some data like the SCSI command and
5378  * the sense key.
5379  *
5380  * Return value:
5381  *	0		- Status is good.
5382  *	EACCES		- Status reports a reservation conflict.
5383  *	ENOTSUP		- Status reports a check condition and sense key
5384  *			  reports an illegal request.
5385  *	EIO		- Any other status.
5386  */
5387 static int
5388 vdc_scsi_status(vdc_t *vdc, vd_scsi_t *vd_scsi, boolean_t log_error)
5389 {
5390 	int rv;
5391 	char path_str[MAXPATHLEN];
5392 	char panic_str[VDC_RESV_CONFLICT_FMT_LEN + MAXPATHLEN];
5393 	union scsi_cdb *cdb;
5394 	struct scsi_extended_sense *sense;
5395 
5396 	if (vd_scsi->cmd_status == STATUS_GOOD)
5397 		/* no error */
5398 		return (0);
5399 
5400 	/* when the tunable vdc_scsi_log_error is true we log all errors */
5401 	if (vdc_scsi_log_error)
5402 		log_error = B_TRUE;
5403 
5404 	if (log_error) {
5405 		cmn_err(CE_WARN, "%s (vdc%d):\tError for Command: 0x%x)\n",
5406 		    ddi_pathname(vdc->dip, path_str), vdc->instance,
5407 		    GETCMD(VD_SCSI_DATA_CDB(vd_scsi)));
5408 	}
5409 
5410 	/* default returned value */
5411 	rv = EIO;
5412 
5413 	switch (vd_scsi->cmd_status) {
5414 
5415 	case STATUS_CHECK:
5416 	case STATUS_TERMINATED:
5417 		if (log_error)
5418 			cmn_err(CE_CONT, "\tCheck Condition Error\n");
5419 
5420 		/* check sense buffer */
5421 		if (vd_scsi->sense_len == 0 ||
5422 		    vd_scsi->sense_status != STATUS_GOOD) {
5423 			if (log_error)
5424 				cmn_err(CE_CONT, "\tNo Sense Data Available\n");
5425 			break;
5426 		}
5427 
5428 		sense = VD_SCSI_DATA_SENSE(vd_scsi);
5429 
5430 		if (log_error) {
5431 			cmn_err(CE_CONT, "\tSense Key:  0x%x\n"
5432 			    "\tASC: 0x%x, ASCQ: 0x%x\n",
5433 			    scsi_sense_key((uint8_t *)sense),
5434 			    scsi_sense_asc((uint8_t *)sense),
5435 			    scsi_sense_ascq((uint8_t *)sense));
5436 		}
5437 
5438 		if (scsi_sense_key((uint8_t *)sense) == KEY_ILLEGAL_REQUEST)
5439 			rv = ENOTSUP;
5440 		break;
5441 
5442 	case STATUS_BUSY:
5443 		if (log_error)
5444 			cmn_err(CE_NOTE, "\tDevice Busy\n");
5445 		break;
5446 
5447 	case STATUS_RESERVATION_CONFLICT:
5448 		/*
5449 		 * If the command was PERSISTENT_RESERVATION_[IN|OUT] then
5450 		 * reservation conflict could be due to various reasons like
5451 		 * incorrect keys, not registered or not reserved etc. So,
5452 		 * we should not panic in that case.
5453 		 */
5454 		cdb = VD_SCSI_DATA_CDB(vd_scsi);
5455 		if (vdc->failfast_interval != 0 &&
5456 		    cdb->scc_cmd != SCMD_PERSISTENT_RESERVE_IN &&
5457 		    cdb->scc_cmd != SCMD_PERSISTENT_RESERVE_OUT) {
5458 			/* failfast is enabled so we have to panic */
5459 			(void) snprintf(panic_str, sizeof (panic_str),
5460 			    VDC_RESV_CONFLICT_FMT_STR "%s",
5461 			    ddi_pathname(vdc->dip, path_str));
5462 			panic(panic_str);
5463 		}
5464 		if (log_error)
5465 			cmn_err(CE_NOTE, "\tReservation Conflict\n");
5466 		rv = EACCES;
5467 		break;
5468 
5469 	case STATUS_QFULL:
5470 		if (log_error)
5471 			cmn_err(CE_NOTE, "\tQueue Full\n");
5472 		break;
5473 
5474 	case STATUS_MET:
5475 	case STATUS_INTERMEDIATE:
5476 	case STATUS_SCSI2:
5477 	case STATUS_INTERMEDIATE_MET:
5478 	case STATUS_ACA_ACTIVE:
5479 		if (log_error)
5480 			cmn_err(CE_CONT,
5481 			    "\tUnexpected SCSI status received: 0x%x\n",
5482 			    vd_scsi->cmd_status);
5483 		break;
5484 
5485 	default:
5486 		if (log_error)
5487 			cmn_err(CE_CONT,
5488 			    "\tInvalid SCSI status received: 0x%x\n",
5489 			    vd_scsi->cmd_status);
5490 		break;
5491 	}
5492 
5493 	return (rv);
5494 }
5495 
5496 /*
5497  * Implemented the USCSICMD uscsi(7I) ioctl. This ioctl is converted to
5498  * a VD_OP_SCSICMD operation which is sent to the vdisk server. If a SCSI
5499  * reset is requested (i.e. a flag USCSI_RESET* is set) then the ioctl is
5500  * converted to a VD_OP_RESET operation.
5501  */
5502 static int
5503 vdc_uscsi_cmd(vdc_t *vdc, caddr_t arg, int mode)
5504 {
5505 	struct uscsi_cmd 	uscsi;
5506 	struct uscsi_cmd32	uscsi32;
5507 	vd_scsi_t 		*vd_scsi;
5508 	int 			vd_scsi_len;
5509 	union scsi_cdb		*cdb;
5510 	struct scsi_extended_sense *sense;
5511 	char 			*datain, *dataout;
5512 	size_t			cdb_len, datain_len, dataout_len, sense_len;
5513 	int 			rv;
5514 
5515 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5516 		if (ddi_copyin(arg, &uscsi32, sizeof (struct uscsi_cmd32),
5517 		    mode) != 0)
5518 			return (EFAULT);
5519 		uscsi_cmd32touscsi_cmd((&uscsi32), (&uscsi));
5520 	} else {
5521 		if (ddi_copyin(arg, &uscsi, sizeof (struct uscsi_cmd),
5522 		    mode) != 0)
5523 			return (EFAULT);
5524 	}
5525 
5526 	/* a uscsi reset is converted to a VD_OP_RESET operation */
5527 	if (uscsi.uscsi_flags & (USCSI_RESET | USCSI_RESET_LUN |
5528 	    USCSI_RESET_ALL)) {
5529 		rv = vdc_do_sync_op(vdc, VD_OP_RESET, NULL, 0, 0, 0, CB_SYNC,
5530 		    (void *)(uint64_t)mode, VIO_both_dir, B_TRUE);
5531 		return (rv);
5532 	}
5533 
5534 	/* cdb buffer length */
5535 	cdb_len = uscsi.uscsi_cdblen;
5536 
5537 	/* data in and out buffers length */
5538 	if (uscsi.uscsi_flags & USCSI_READ) {
5539 		datain_len = uscsi.uscsi_buflen;
5540 		dataout_len = 0;
5541 	} else {
5542 		datain_len = 0;
5543 		dataout_len = uscsi.uscsi_buflen;
5544 	}
5545 
5546 	/* sense buffer length */
5547 	if (uscsi.uscsi_flags & USCSI_RQENABLE)
5548 		sense_len = uscsi.uscsi_rqlen;
5549 	else
5550 		sense_len = 0;
5551 
5552 	/* allocate buffer for the VD_SCSICMD_OP operation */
5553 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, datain_len, dataout_len,
5554 	    &vd_scsi_len);
5555 
5556 	/*
5557 	 * The documentation of USCSI_ISOLATE and USCSI_DIAGNOSE is very vague,
5558 	 * but basically they prevent a SCSI command from being retried in case
5559 	 * of an error.
5560 	 */
5561 	if ((uscsi.uscsi_flags & USCSI_ISOLATE) ||
5562 	    (uscsi.uscsi_flags & USCSI_DIAGNOSE))
5563 		vd_scsi->options |= VD_SCSI_OPT_NORETRY;
5564 
5565 	/* set task attribute */
5566 	if (uscsi.uscsi_flags & USCSI_NOTAG) {
5567 		vd_scsi->task_attribute = 0;
5568 	} else {
5569 		if (uscsi.uscsi_flags & USCSI_HEAD)
5570 			vd_scsi->task_attribute = VD_SCSI_TASK_ACA;
5571 		else if (uscsi.uscsi_flags & USCSI_HTAG)
5572 			vd_scsi->task_attribute = VD_SCSI_TASK_HQUEUE;
5573 		else if (uscsi.uscsi_flags & USCSI_OTAG)
5574 			vd_scsi->task_attribute = VD_SCSI_TASK_ORDERED;
5575 		else
5576 			vd_scsi->task_attribute = 0;
5577 	}
5578 
5579 	/* set timeout */
5580 	vd_scsi->timeout = uscsi.uscsi_timeout;
5581 
5582 	/* copy-in cdb data */
5583 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5584 	if (ddi_copyin(uscsi.uscsi_cdb, cdb, cdb_len, mode) != 0) {
5585 		rv = EFAULT;
5586 		goto done;
5587 	}
5588 
5589 	/* keep a pointer to the sense buffer */
5590 	sense = VD_SCSI_DATA_SENSE(vd_scsi);
5591 
5592 	/* keep a pointer to the data-in buffer */
5593 	datain = (char *)VD_SCSI_DATA_IN(vd_scsi);
5594 
5595 	/* copy-in request data to the data-out buffer */
5596 	dataout = (char *)VD_SCSI_DATA_OUT(vd_scsi);
5597 	if (!(uscsi.uscsi_flags & USCSI_READ)) {
5598 		if (ddi_copyin(uscsi.uscsi_bufaddr, dataout, dataout_len,
5599 		    mode)) {
5600 			rv = EFAULT;
5601 			goto done;
5602 		}
5603 	}
5604 
5605 	/* submit the request */
5606 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5607 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5608 
5609 	if (rv != 0)
5610 		goto done;
5611 
5612 	/* update scsi status */
5613 	uscsi.uscsi_status = vd_scsi->cmd_status;
5614 
5615 	/* update sense data */
5616 	if ((uscsi.uscsi_flags & USCSI_RQENABLE) &&
5617 	    (uscsi.uscsi_status == STATUS_CHECK ||
5618 	    uscsi.uscsi_status == STATUS_TERMINATED)) {
5619 
5620 		uscsi.uscsi_rqstatus = vd_scsi->sense_status;
5621 
5622 		if (uscsi.uscsi_rqstatus == STATUS_GOOD) {
5623 			uscsi.uscsi_rqresid = uscsi.uscsi_rqlen -
5624 			    vd_scsi->sense_len;
5625 			if (ddi_copyout(sense, uscsi.uscsi_rqbuf,
5626 			    vd_scsi->sense_len, mode) != 0) {
5627 				rv = EFAULT;
5628 				goto done;
5629 			}
5630 		}
5631 	}
5632 
5633 	/* update request data */
5634 	if (uscsi.uscsi_status == STATUS_GOOD) {
5635 		if (uscsi.uscsi_flags & USCSI_READ) {
5636 			uscsi.uscsi_resid = uscsi.uscsi_buflen -
5637 			    vd_scsi->datain_len;
5638 			if (ddi_copyout(datain, uscsi.uscsi_bufaddr,
5639 			    vd_scsi->datain_len, mode) != 0) {
5640 				rv = EFAULT;
5641 				goto done;
5642 			}
5643 		} else {
5644 			uscsi.uscsi_resid = uscsi.uscsi_buflen -
5645 			    vd_scsi->dataout_len;
5646 		}
5647 	}
5648 
5649 	/* copy-out result */
5650 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5651 		uscsi_cmdtouscsi_cmd32((&uscsi), (&uscsi32));
5652 		if (ddi_copyout(&uscsi32, arg, sizeof (struct uscsi_cmd32),
5653 		    mode) != 0) {
5654 			rv = EFAULT;
5655 			goto done;
5656 		}
5657 	} else {
5658 		if (ddi_copyout(&uscsi, arg, sizeof (struct uscsi_cmd),
5659 		    mode) != 0) {
5660 			rv = EFAULT;
5661 			goto done;
5662 		}
5663 	}
5664 
5665 	/* get the return code from the SCSI command status */
5666 	rv = vdc_scsi_status(vdc, vd_scsi,
5667 	    !(uscsi.uscsi_flags & USCSI_SILENT));
5668 
5669 done:
5670 	kmem_free(vd_scsi, vd_scsi_len);
5671 	return (rv);
5672 }
5673 
5674 /*
5675  * Create a VD_OP_SCSICMD buffer for a SCSI PERSISTENT IN command.
5676  *
5677  * Arguments:
5678  *	cmd		- SCSI PERSISTENT IN command
5679  *	len		- length of the SCSI input buffer
5680  *	vd_scsi_len	- return the length of the allocated buffer
5681  *
5682  * Returned Value:
5683  *	a pointer to the allocated VD_OP_SCSICMD buffer.
5684  */
5685 static vd_scsi_t *
5686 vdc_scsi_alloc_persistent_in(uchar_t cmd, int len, int *vd_scsi_len)
5687 {
5688 	int cdb_len, sense_len, datain_len, dataout_len;
5689 	vd_scsi_t *vd_scsi;
5690 	union scsi_cdb *cdb;
5691 
5692 	cdb_len = CDB_GROUP1;
5693 	sense_len = sizeof (struct scsi_extended_sense);
5694 	datain_len = len;
5695 	dataout_len = 0;
5696 
5697 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, datain_len, dataout_len,
5698 	    vd_scsi_len);
5699 
5700 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5701 
5702 	/* set cdb */
5703 	cdb->scc_cmd = SCMD_PERSISTENT_RESERVE_IN;
5704 	cdb->cdb_opaque[1] = cmd;
5705 	FORMG1COUNT(cdb, datain_len);
5706 
5707 	vd_scsi->timeout = vdc_scsi_timeout;
5708 
5709 	return (vd_scsi);
5710 }
5711 
5712 /*
5713  * Create a VD_OP_SCSICMD buffer for a SCSI PERSISTENT OUT command.
5714  *
5715  * Arguments:
5716  *	cmd		- SCSI PERSISTENT OUT command
5717  *	len		- length of the SCSI output buffer
5718  *	vd_scsi_len	- return the length of the allocated buffer
5719  *
5720  * Returned Code:
5721  *	a pointer to the allocated VD_OP_SCSICMD buffer.
5722  */
5723 static vd_scsi_t *
5724 vdc_scsi_alloc_persistent_out(uchar_t cmd, int len, int *vd_scsi_len)
5725 {
5726 	int cdb_len, sense_len, datain_len, dataout_len;
5727 	vd_scsi_t *vd_scsi;
5728 	union scsi_cdb *cdb;
5729 
5730 	cdb_len = CDB_GROUP1;
5731 	sense_len = sizeof (struct scsi_extended_sense);
5732 	datain_len = 0;
5733 	dataout_len = len;
5734 
5735 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, datain_len, dataout_len,
5736 	    vd_scsi_len);
5737 
5738 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
5739 
5740 	/* set cdb */
5741 	cdb->scc_cmd = SCMD_PERSISTENT_RESERVE_OUT;
5742 	cdb->cdb_opaque[1] = cmd;
5743 	FORMG1COUNT(cdb, dataout_len);
5744 
5745 	vd_scsi->timeout = vdc_scsi_timeout;
5746 
5747 	return (vd_scsi);
5748 }
5749 
5750 /*
5751  * Implement the MHIOCGRP_INKEYS mhd(7i) ioctl. The ioctl is converted
5752  * to a SCSI PERSISTENT IN READ KEYS command which is sent to the vdisk
5753  * server with a VD_OP_SCSICMD operation.
5754  */
5755 static int
5756 vdc_mhd_inkeys(vdc_t *vdc, caddr_t arg, int mode)
5757 {
5758 	vd_scsi_t *vd_scsi;
5759 	mhioc_inkeys_t inkeys;
5760 	mhioc_key_list_t klist;
5761 	struct mhioc_inkeys32 inkeys32;
5762 	struct mhioc_key_list32 klist32;
5763 	sd_prin_readkeys_t *scsi_keys;
5764 	void *user_keys;
5765 	int vd_scsi_len;
5766 	int listsize, listlen, rv;
5767 
5768 	/* copyin arguments */
5769 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5770 		rv = ddi_copyin(arg, &inkeys32, sizeof (inkeys32), mode);
5771 		if (rv != 0)
5772 			return (EFAULT);
5773 
5774 		rv = ddi_copyin((caddr_t)(uintptr_t)inkeys32.li, &klist32,
5775 		    sizeof (klist32), mode);
5776 		if (rv != 0)
5777 			return (EFAULT);
5778 
5779 		listsize = klist32.listsize;
5780 	} else {
5781 		rv = ddi_copyin(arg, &inkeys, sizeof (inkeys), mode);
5782 		if (rv != 0)
5783 			return (EFAULT);
5784 
5785 		rv = ddi_copyin(inkeys.li, &klist, sizeof (klist), mode);
5786 		if (rv != 0)
5787 			return (EFAULT);
5788 
5789 		listsize = klist.listsize;
5790 	}
5791 
5792 	/* build SCSI VD_OP request */
5793 	vd_scsi = vdc_scsi_alloc_persistent_in(SD_READ_KEYS,
5794 	    sizeof (sd_prin_readkeys_t) - sizeof (caddr_t) +
5795 	    (sizeof (mhioc_resv_key_t) * listsize), &vd_scsi_len);
5796 
5797 	scsi_keys = (sd_prin_readkeys_t *)VD_SCSI_DATA_IN(vd_scsi);
5798 
5799 	/* submit the request */
5800 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5801 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5802 
5803 	if (rv != 0)
5804 		goto done;
5805 
5806 	listlen = scsi_keys->len / MHIOC_RESV_KEY_SIZE;
5807 
5808 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5809 		inkeys32.generation = scsi_keys->generation;
5810 		rv = ddi_copyout(&inkeys32, arg, sizeof (inkeys32), mode);
5811 		if (rv != 0) {
5812 			rv = EFAULT;
5813 			goto done;
5814 		}
5815 
5816 		klist32.listlen = listlen;
5817 		rv = ddi_copyout(&klist32, (caddr_t)(uintptr_t)inkeys32.li,
5818 		    sizeof (klist32), mode);
5819 		if (rv != 0) {
5820 			rv = EFAULT;
5821 			goto done;
5822 		}
5823 
5824 		user_keys = (caddr_t)(uintptr_t)klist32.list;
5825 	} else {
5826 		inkeys.generation = scsi_keys->generation;
5827 		rv = ddi_copyout(&inkeys, arg, sizeof (inkeys), mode);
5828 		if (rv != 0) {
5829 			rv = EFAULT;
5830 			goto done;
5831 		}
5832 
5833 		klist.listlen = listlen;
5834 		rv = ddi_copyout(&klist, inkeys.li, sizeof (klist), mode);
5835 		if (rv != 0) {
5836 			rv = EFAULT;
5837 			goto done;
5838 		}
5839 
5840 		user_keys = klist.list;
5841 	}
5842 
5843 	/* copy out keys */
5844 	if (listlen > 0 && listsize > 0) {
5845 		if (listsize < listlen)
5846 			listlen = listsize;
5847 		rv = ddi_copyout(&scsi_keys->keylist, user_keys,
5848 		    listlen * MHIOC_RESV_KEY_SIZE, mode);
5849 		if (rv != 0)
5850 			rv = EFAULT;
5851 	}
5852 
5853 	if (rv == 0)
5854 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5855 
5856 done:
5857 	kmem_free(vd_scsi, vd_scsi_len);
5858 
5859 	return (rv);
5860 }
5861 
5862 /*
5863  * Implement the MHIOCGRP_INRESV mhd(7i) ioctl. The ioctl is converted
5864  * to a SCSI PERSISTENT IN READ RESERVATION command which is sent to
5865  * the vdisk server with a VD_OP_SCSICMD operation.
5866  */
5867 static int
5868 vdc_mhd_inresv(vdc_t *vdc, caddr_t arg, int mode)
5869 {
5870 	vd_scsi_t *vd_scsi;
5871 	mhioc_inresvs_t inresv;
5872 	mhioc_resv_desc_list_t rlist;
5873 	struct mhioc_inresvs32 inresv32;
5874 	struct mhioc_resv_desc_list32 rlist32;
5875 	mhioc_resv_desc_t mhd_resv;
5876 	sd_prin_readresv_t *scsi_resv;
5877 	sd_readresv_desc_t *resv;
5878 	mhioc_resv_desc_t *user_resv;
5879 	int vd_scsi_len;
5880 	int listsize, listlen, i, rv;
5881 
5882 	/* copyin arguments */
5883 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5884 		rv = ddi_copyin(arg, &inresv32, sizeof (inresv32), mode);
5885 		if (rv != 0)
5886 			return (EFAULT);
5887 
5888 		rv = ddi_copyin((caddr_t)(uintptr_t)inresv32.li, &rlist32,
5889 		    sizeof (rlist32), mode);
5890 		if (rv != 0)
5891 			return (EFAULT);
5892 
5893 		listsize = rlist32.listsize;
5894 	} else {
5895 		rv = ddi_copyin(arg, &inresv, sizeof (inresv), mode);
5896 		if (rv != 0)
5897 			return (EFAULT);
5898 
5899 		rv = ddi_copyin(inresv.li, &rlist, sizeof (rlist), mode);
5900 		if (rv != 0)
5901 			return (EFAULT);
5902 
5903 		listsize = rlist.listsize;
5904 	}
5905 
5906 	/* build SCSI VD_OP request */
5907 	vd_scsi = vdc_scsi_alloc_persistent_in(SD_READ_RESV,
5908 	    sizeof (sd_prin_readresv_t) - sizeof (caddr_t) +
5909 	    (SCSI3_RESV_DESC_LEN * listsize), &vd_scsi_len);
5910 
5911 	scsi_resv = (sd_prin_readresv_t *)VD_SCSI_DATA_IN(vd_scsi);
5912 
5913 	/* submit the request */
5914 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
5915 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
5916 
5917 	if (rv != 0)
5918 		goto done;
5919 
5920 	listlen = scsi_resv->len / SCSI3_RESV_DESC_LEN;
5921 
5922 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
5923 		inresv32.generation = scsi_resv->generation;
5924 		rv = ddi_copyout(&inresv32, arg, sizeof (inresv32), mode);
5925 		if (rv != 0) {
5926 			rv = EFAULT;
5927 			goto done;
5928 		}
5929 
5930 		rlist32.listlen = listlen;
5931 		rv = ddi_copyout(&rlist32, (caddr_t)(uintptr_t)inresv32.li,
5932 		    sizeof (rlist32), mode);
5933 		if (rv != 0) {
5934 			rv = EFAULT;
5935 			goto done;
5936 		}
5937 
5938 		user_resv = (mhioc_resv_desc_t *)(uintptr_t)rlist32.list;
5939 	} else {
5940 		inresv.generation = scsi_resv->generation;
5941 		rv = ddi_copyout(&inresv, arg, sizeof (inresv), mode);
5942 		if (rv != 0) {
5943 			rv = EFAULT;
5944 			goto done;
5945 		}
5946 
5947 		rlist.listlen = listlen;
5948 		rv = ddi_copyout(&rlist, inresv.li, sizeof (rlist), mode);
5949 		if (rv != 0) {
5950 			rv = EFAULT;
5951 			goto done;
5952 		}
5953 
5954 		user_resv = rlist.list;
5955 	}
5956 
5957 	/* copy out reservations */
5958 	if (listsize > 0 && listlen > 0) {
5959 		if (listsize < listlen)
5960 			listlen = listsize;
5961 		resv = (sd_readresv_desc_t *)&scsi_resv->readresv_desc;
5962 
5963 		for (i = 0; i < listlen; i++) {
5964 			mhd_resv.type = resv->type;
5965 			mhd_resv.scope = resv->scope;
5966 			mhd_resv.scope_specific_addr =
5967 			    BE_32(resv->scope_specific_addr);
5968 			bcopy(&resv->resvkey, &mhd_resv.key,
5969 			    MHIOC_RESV_KEY_SIZE);
5970 
5971 			rv = ddi_copyout(&mhd_resv, user_resv,
5972 			    sizeof (mhd_resv), mode);
5973 			if (rv != 0) {
5974 				rv = EFAULT;
5975 				goto done;
5976 			}
5977 			resv++;
5978 			user_resv++;
5979 		}
5980 	}
5981 
5982 	if (rv == 0)
5983 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
5984 
5985 done:
5986 	kmem_free(vd_scsi, vd_scsi_len);
5987 	return (rv);
5988 }
5989 
5990 /*
5991  * Implement the MHIOCGRP_REGISTER mhd(7i) ioctl. The ioctl is converted
5992  * to a SCSI PERSISTENT OUT REGISTER command which is sent to the vdisk
5993  * server with a VD_OP_SCSICMD operation.
5994  */
5995 static int
5996 vdc_mhd_register(vdc_t *vdc, caddr_t arg, int mode)
5997 {
5998 	vd_scsi_t *vd_scsi;
5999 	sd_prout_t *scsi_prout;
6000 	mhioc_register_t mhd_reg;
6001 	int vd_scsi_len, rv;
6002 
6003 	/* copyin arguments */
6004 	rv = ddi_copyin(arg, &mhd_reg, sizeof (mhd_reg), mode);
6005 	if (rv != 0)
6006 		return (EFAULT);
6007 
6008 	/* build SCSI VD_OP request */
6009 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_REGISTER,
6010 	    sizeof (sd_prout_t), &vd_scsi_len);
6011 
6012 	/* set parameters */
6013 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
6014 	bcopy(mhd_reg.oldkey.key, scsi_prout->res_key, MHIOC_RESV_KEY_SIZE);
6015 	bcopy(mhd_reg.newkey.key, scsi_prout->service_key, MHIOC_RESV_KEY_SIZE);
6016 	scsi_prout->aptpl = (uchar_t)mhd_reg.aptpl;
6017 
6018 	/* submit the request */
6019 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
6020 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
6021 
6022 	if (rv == 0)
6023 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
6024 
6025 	kmem_free(vd_scsi, vd_scsi_len);
6026 	return (rv);
6027 }
6028 
6029 /*
6030  * Implement the MHIOCGRP_RESERVE mhd(7i) ioctl. The ioctl is converted
6031  * to a SCSI PERSISTENT OUT RESERVE command which is sent to the vdisk
6032  * server with a VD_OP_SCSICMD operation.
6033  */
6034 static int
6035 vdc_mhd_reserve(vdc_t *vdc, caddr_t arg, int mode)
6036 {
6037 	union scsi_cdb *cdb;
6038 	vd_scsi_t *vd_scsi;
6039 	sd_prout_t *scsi_prout;
6040 	mhioc_resv_desc_t mhd_resv;
6041 	int vd_scsi_len, rv;
6042 
6043 	/* copyin arguments */
6044 	rv = ddi_copyin(arg, &mhd_resv, sizeof (mhd_resv), mode);
6045 	if (rv != 0)
6046 		return (EFAULT);
6047 
6048 	/* build SCSI VD_OP request */
6049 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_RESERVE,
6050 	    sizeof (sd_prout_t), &vd_scsi_len);
6051 
6052 	/* set parameters */
6053 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
6054 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
6055 	bcopy(mhd_resv.key.key, scsi_prout->res_key, MHIOC_RESV_KEY_SIZE);
6056 	scsi_prout->scope_address = mhd_resv.scope_specific_addr;
6057 	cdb->cdb_opaque[2] = mhd_resv.type;
6058 
6059 	/* submit the request */
6060 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
6061 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
6062 
6063 	if (rv == 0)
6064 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
6065 
6066 	kmem_free(vd_scsi, vd_scsi_len);
6067 	return (rv);
6068 }
6069 
6070 /*
6071  * Implement the MHIOCGRP_PREEMPTANDABORT mhd(7i) ioctl. The ioctl is
6072  * converted to a SCSI PERSISTENT OUT PREEMPT AND ABORT command which
6073  * is sent to the vdisk server with a VD_OP_SCSICMD operation.
6074  */
6075 static int
6076 vdc_mhd_preemptabort(vdc_t *vdc, caddr_t arg, int mode)
6077 {
6078 	union scsi_cdb *cdb;
6079 	vd_scsi_t *vd_scsi;
6080 	sd_prout_t *scsi_prout;
6081 	mhioc_preemptandabort_t mhd_preempt;
6082 	int vd_scsi_len, rv;
6083 
6084 	/* copyin arguments */
6085 	rv = ddi_copyin(arg, &mhd_preempt, sizeof (mhd_preempt), mode);
6086 	if (rv != 0)
6087 		return (EFAULT);
6088 
6089 	/* build SCSI VD_OP request */
6090 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_PREEMPTANDABORT,
6091 	    sizeof (sd_prout_t), &vd_scsi_len);
6092 
6093 	/* set parameters */
6094 	vd_scsi->task_attribute = VD_SCSI_TASK_ACA;
6095 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
6096 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
6097 	bcopy(mhd_preempt.resvdesc.key.key, scsi_prout->res_key,
6098 	    MHIOC_RESV_KEY_SIZE);
6099 	bcopy(mhd_preempt.victim_key.key, scsi_prout->service_key,
6100 	    MHIOC_RESV_KEY_SIZE);
6101 	scsi_prout->scope_address = mhd_preempt.resvdesc.scope_specific_addr;
6102 	cdb->cdb_opaque[2] = mhd_preempt.resvdesc.type;
6103 
6104 	/* submit the request */
6105 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
6106 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
6107 
6108 	if (rv == 0)
6109 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
6110 
6111 	kmem_free(vd_scsi, vd_scsi_len);
6112 	return (rv);
6113 }
6114 
6115 /*
6116  * Implement the MHIOCGRP_REGISTERANDIGNOREKEY mhd(7i) ioctl. The ioctl
6117  * is converted to a SCSI PERSISTENT OUT REGISTER AND IGNORE EXISTING KEY
6118  * command which is sent to the vdisk server with a VD_OP_SCSICMD operation.
6119  */
6120 static int
6121 vdc_mhd_registerignore(vdc_t *vdc, caddr_t arg, int mode)
6122 {
6123 	vd_scsi_t *vd_scsi;
6124 	sd_prout_t *scsi_prout;
6125 	mhioc_registerandignorekey_t mhd_regi;
6126 	int vd_scsi_len, rv;
6127 
6128 	/* copyin arguments */
6129 	rv = ddi_copyin(arg, &mhd_regi, sizeof (mhd_regi), mode);
6130 	if (rv != 0)
6131 		return (EFAULT);
6132 
6133 	/* build SCSI VD_OP request */
6134 	vd_scsi = vdc_scsi_alloc_persistent_out(SD_SCSI3_REGISTERANDIGNOREKEY,
6135 	    sizeof (sd_prout_t), &vd_scsi_len);
6136 
6137 	/* set parameters */
6138 	scsi_prout = (sd_prout_t *)VD_SCSI_DATA_OUT(vd_scsi);
6139 	bcopy(mhd_regi.newkey.key, scsi_prout->service_key,
6140 	    MHIOC_RESV_KEY_SIZE);
6141 	scsi_prout->aptpl = (uchar_t)mhd_regi.aptpl;
6142 
6143 	/* submit the request */
6144 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
6145 	    0, 0, CB_SYNC, (void *)(uint64_t)mode, VIO_both_dir, B_FALSE);
6146 
6147 	if (rv == 0)
6148 		rv = vdc_scsi_status(vdc, vd_scsi, B_FALSE);
6149 
6150 	kmem_free(vd_scsi, vd_scsi_len);
6151 	return (rv);
6152 }
6153 
6154 /*
6155  * This function is used by the failfast mechanism to send a SCSI command
6156  * to check for reservation conflict.
6157  */
6158 static int
6159 vdc_failfast_scsi_cmd(vdc_t *vdc, uchar_t scmd)
6160 {
6161 	int cdb_len, sense_len, vd_scsi_len;
6162 	vd_scsi_t *vd_scsi;
6163 	union scsi_cdb *cdb;
6164 	int rv;
6165 
6166 	ASSERT(scmd == SCMD_TEST_UNIT_READY || scmd == SCMD_WRITE_G1);
6167 
6168 	if (scmd == SCMD_WRITE_G1)
6169 		cdb_len = CDB_GROUP1;
6170 	else
6171 		cdb_len = CDB_GROUP0;
6172 
6173 	sense_len = sizeof (struct scsi_extended_sense);
6174 
6175 	vd_scsi = vdc_scsi_alloc(cdb_len, sense_len, 0, 0, &vd_scsi_len);
6176 
6177 	/* set cdb */
6178 	cdb = VD_SCSI_DATA_CDB(vd_scsi);
6179 	cdb->scc_cmd = scmd;
6180 
6181 	vd_scsi->timeout = vdc_scsi_timeout;
6182 
6183 	/*
6184 	 * Submit the request. The last argument has to be B_FALSE so that
6185 	 * vdc_do_sync_op does not loop checking for reservation conflict if
6186 	 * the operation returns an error.
6187 	 */
6188 	rv = vdc_do_sync_op(vdc, VD_OP_SCSICMD, (caddr_t)vd_scsi, vd_scsi_len,
6189 	    0, 0, CB_SYNC, (void *)(uint64_t)FKIOCTL, VIO_both_dir, B_FALSE);
6190 
6191 	if (rv == 0)
6192 		(void) vdc_scsi_status(vdc, vd_scsi, B_FALSE);
6193 
6194 	kmem_free(vd_scsi, vd_scsi_len);
6195 	return (rv);
6196 }
6197 
6198 /*
6199  * This function is used by the failfast mechanism to check for reservation
6200  * conflict. It sends some SCSI commands which will fail with a reservation
6201  * conflict error if the system does not have access to the disk and this
6202  * will panic the system.
6203  *
6204  * Returned Code:
6205  *	0	- disk is accessible without reservation conflict error
6206  *	!= 0	- unable to check if disk is accessible
6207  */
6208 int
6209 vdc_failfast_check_resv(vdc_t *vdc)
6210 {
6211 	int failure = 0;
6212 
6213 	/*
6214 	 * Send a TEST UNIT READY command. The command will panic
6215 	 * the system if it fails with a reservation conflict.
6216 	 */
6217 	if (vdc_failfast_scsi_cmd(vdc, SCMD_TEST_UNIT_READY) != 0)
6218 		failure++;
6219 
6220 	/*
6221 	 * With SPC-3 compliant devices TEST UNIT READY will succeed on
6222 	 * a reserved device, so we also do a WRITE(10) of zero byte in
6223 	 * order to provoke a Reservation Conflict status on those newer
6224 	 * devices.
6225 	 */
6226 	if (vdc_failfast_scsi_cmd(vdc, SCMD_WRITE_G1) != 0)
6227 		failure++;
6228 
6229 	return (failure);
6230 }
6231 
6232 /*
6233  * Add a pending I/O to the failfast I/O queue. An I/O is added to this
6234  * queue when it has failed and failfast is enabled. Then we have to check
6235  * if it has failed because of a reservation conflict in which case we have
6236  * to panic the system.
6237  *
6238  * Async I/O should be queued with their block I/O data transfer structure
6239  * (buf). Sync I/O should be queued with buf = NULL.
6240  */
6241 static vdc_io_t *
6242 vdc_failfast_io_queue(vdc_t *vdc, struct buf *buf)
6243 {
6244 	vdc_io_t *vio;
6245 
6246 	ASSERT(MUTEX_HELD(&vdc->lock));
6247 
6248 	vio = kmem_alloc(sizeof (vdc_io_t), KM_SLEEP);
6249 	vio->vio_next = vdc->failfast_io_queue;
6250 	vio->vio_buf = buf;
6251 	vio->vio_qtime = ddi_get_lbolt();
6252 
6253 	vdc->failfast_io_queue = vio;
6254 
6255 	/* notify the failfast thread that a new I/O is queued */
6256 	cv_signal(&vdc->failfast_cv);
6257 
6258 	return (vio);
6259 }
6260 
6261 /*
6262  * Remove and complete I/O in the failfast I/O queue which have been
6263  * added after the indicated deadline. A deadline of 0 means that all
6264  * I/O have to be unqueued and marked as completed.
6265  */
6266 static void
6267 vdc_failfast_io_unqueue(vdc_t *vdc, clock_t deadline)
6268 {
6269 	vdc_io_t *vio, *vio_tmp;
6270 
6271 	ASSERT(MUTEX_HELD(&vdc->lock));
6272 
6273 	vio_tmp = NULL;
6274 	vio = vdc->failfast_io_queue;
6275 
6276 	if (deadline != 0) {
6277 		/*
6278 		 * Skip any io queued after the deadline. The failfast
6279 		 * I/O queue is ordered starting with the last I/O added
6280 		 * to the queue.
6281 		 */
6282 		while (vio != NULL && vio->vio_qtime > deadline) {
6283 			vio_tmp = vio;
6284 			vio = vio->vio_next;
6285 		}
6286 	}
6287 
6288 	if (vio == NULL)
6289 		/* nothing to unqueue */
6290 		return;
6291 
6292 	/* update the queue */
6293 	if (vio_tmp == NULL)
6294 		vdc->failfast_io_queue = NULL;
6295 	else
6296 		vio_tmp->vio_next = NULL;
6297 
6298 	/*
6299 	 * Complete unqueued I/O. Async I/O have a block I/O data transfer
6300 	 * structure (buf) and they are completed by calling biodone(). Sync
6301 	 * I/O do not have a buf and they are completed by setting the
6302 	 * vio_qtime to zero and signaling failfast_io_cv. In that case, the
6303 	 * thread waiting for the I/O to complete is responsible for freeing
6304 	 * the vio structure.
6305 	 */
6306 	while (vio != NULL) {
6307 		vio_tmp = vio->vio_next;
6308 		if (vio->vio_buf != NULL) {
6309 			VD_KSTAT_RUNQ_EXIT(vdc);
6310 			DTRACE_IO1(done, buf_t *, vio->vio_buf);
6311 			biodone(vio->vio_buf);
6312 			kmem_free(vio, sizeof (vdc_io_t));
6313 		} else {
6314 			vio->vio_qtime = 0;
6315 		}
6316 		vio = vio_tmp;
6317 	}
6318 
6319 	cv_broadcast(&vdc->failfast_io_cv);
6320 }
6321 
6322 /*
6323  * Failfast Thread.
6324  *
6325  * While failfast is enabled, the failfast thread sends a TEST UNIT READY
6326  * and a zero size WRITE(10) SCSI commands on a regular basis to check that
6327  * we still have access to the disk. If a command fails with a RESERVATION
6328  * CONFLICT error then the system will immediatly panic.
6329  *
6330  * The failfast thread is also woken up when an I/O has failed. It then check
6331  * the access to the disk to ensure that the I/O failure was not due to a
6332  * reservation conflict.
6333  *
6334  * There is one failfast thread for each virtual disk for which failfast is
6335  * enabled. We could have only one thread sending requests for all disks but
6336  * this would need vdc to send asynchronous requests and to have callbacks to
6337  * process replies.
6338  */
6339 static void
6340 vdc_failfast_thread(void *arg)
6341 {
6342 	int status;
6343 	vdc_t *vdc = (vdc_t *)arg;
6344 	clock_t timeout, starttime;
6345 
6346 	mutex_enter(&vdc->lock);
6347 
6348 	while (vdc->failfast_interval != 0) {
6349 
6350 		starttime = ddi_get_lbolt();
6351 
6352 		mutex_exit(&vdc->lock);
6353 
6354 		/* check for reservation conflict */
6355 		status = vdc_failfast_check_resv(vdc);
6356 
6357 		mutex_enter(&vdc->lock);
6358 		/*
6359 		 * We have dropped the lock to send the SCSI command so we have
6360 		 * to check that failfast is still enabled.
6361 		 */
6362 		if (vdc->failfast_interval == 0)
6363 			break;
6364 
6365 		/*
6366 		 * If we have successfully check the disk access and there was
6367 		 * no reservation conflict then we can complete any I/O queued
6368 		 * before the last check.
6369 		 */
6370 		if (status == 0)
6371 			vdc_failfast_io_unqueue(vdc, starttime);
6372 
6373 		/* proceed again if some I/O are still in the queue */
6374 		if (vdc->failfast_io_queue != NULL)
6375 			continue;
6376 
6377 		timeout = ddi_get_lbolt() +
6378 		    drv_usectohz(vdc->failfast_interval);
6379 		(void) cv_timedwait(&vdc->failfast_cv, &vdc->lock, timeout);
6380 	}
6381 
6382 	/*
6383 	 * Failfast is being stop so we can complete any queued I/O.
6384 	 */
6385 	vdc_failfast_io_unqueue(vdc, 0);
6386 	vdc->failfast_thread = NULL;
6387 	mutex_exit(&vdc->lock);
6388 	thread_exit();
6389 }
6390 
6391 /*
6392  * Implement the MHIOCENFAILFAST mhd(7i) ioctl.
6393  */
6394 static int
6395 vdc_failfast(vdc_t *vdc, caddr_t arg, int mode)
6396 {
6397 	unsigned int mh_time;
6398 
6399 	if (ddi_copyin((void *)arg, &mh_time, sizeof (int), mode))
6400 		return (EFAULT);
6401 
6402 	mutex_enter(&vdc->lock);
6403 	if (mh_time != 0 && vdc->failfast_thread == NULL) {
6404 		vdc->failfast_thread = thread_create(NULL, 0,
6405 		    vdc_failfast_thread, vdc, 0, &p0, TS_RUN,
6406 		    v.v_maxsyspri - 2);
6407 	}
6408 
6409 	vdc->failfast_interval = mh_time * 1000;
6410 	cv_signal(&vdc->failfast_cv);
6411 	mutex_exit(&vdc->lock);
6412 
6413 	return (0);
6414 }
6415 
6416 /*
6417  * Implement the MHIOCTKOWN and MHIOCRELEASE mhd(7i) ioctls. These ioctls are
6418  * converted to VD_OP_SET_ACCESS operations.
6419  */
6420 static int
6421 vdc_access_set(vdc_t *vdc, uint64_t flags, int mode)
6422 {
6423 	int rv;
6424 
6425 	/* submit owership command request */
6426 	rv = vdc_do_sync_op(vdc, VD_OP_SET_ACCESS, (caddr_t)&flags,
6427 	    sizeof (uint64_t), 0, 0, CB_SYNC, (void *)(uint64_t)mode,
6428 	    VIO_both_dir, B_TRUE);
6429 
6430 	return (rv);
6431 }
6432 
6433 /*
6434  * Implement the MHIOCSTATUS mhd(7i) ioctl. This ioctl is converted to a
6435  * VD_OP_GET_ACCESS operation.
6436  */
6437 static int
6438 vdc_access_get(vdc_t *vdc, uint64_t *status, int mode)
6439 {
6440 	int rv;
6441 
6442 	/* submit owership command request */
6443 	rv = vdc_do_sync_op(vdc, VD_OP_GET_ACCESS, (caddr_t)status,
6444 	    sizeof (uint64_t), 0, 0, CB_SYNC, (void *)(uint64_t)mode,
6445 	    VIO_both_dir, B_TRUE);
6446 
6447 	return (rv);
6448 }
6449 
6450 /*
6451  * Disk Ownership Thread.
6452  *
6453  * When we have taken the ownership of a disk, this thread waits to be
6454  * notified when the LDC channel is reset so that it can recover the
6455  * ownership.
6456  *
6457  * Note that the thread handling the LDC reset (vdc_process_msg_thread())
6458  * can not be used to do the ownership recovery because it has to be
6459  * running to handle the reply message to the ownership operation.
6460  */
6461 static void
6462 vdc_ownership_thread(void *arg)
6463 {
6464 	vdc_t *vdc = (vdc_t *)arg;
6465 	clock_t timeout;
6466 	uint64_t status;
6467 
6468 	mutex_enter(&vdc->ownership_lock);
6469 	mutex_enter(&vdc->lock);
6470 
6471 	while (vdc->ownership & VDC_OWNERSHIP_WANTED) {
6472 
6473 		if ((vdc->ownership & VDC_OWNERSHIP_RESET) ||
6474 		    !(vdc->ownership & VDC_OWNERSHIP_GRANTED)) {
6475 			/*
6476 			 * There was a reset so the ownership has been lost,
6477 			 * try to recover. We do this without using the preempt
6478 			 * option so that we don't steal the ownership from
6479 			 * someone who has preempted us.
6480 			 */
6481 			DMSG(vdc, 0, "[%d] Ownership lost, recovering",
6482 			    vdc->instance);
6483 
6484 			vdc->ownership &= ~(VDC_OWNERSHIP_RESET |
6485 			    VDC_OWNERSHIP_GRANTED);
6486 
6487 			mutex_exit(&vdc->lock);
6488 
6489 			status = vdc_access_set(vdc, VD_ACCESS_SET_EXCLUSIVE |
6490 			    VD_ACCESS_SET_PRESERVE, FKIOCTL);
6491 
6492 			mutex_enter(&vdc->lock);
6493 
6494 			if (status == 0) {
6495 				DMSG(vdc, 0, "[%d] Ownership recovered",
6496 				    vdc->instance);
6497 				vdc->ownership |= VDC_OWNERSHIP_GRANTED;
6498 			} else {
6499 				DMSG(vdc, 0, "[%d] Fail to recover ownership",
6500 				    vdc->instance);
6501 			}
6502 
6503 		}
6504 
6505 		/*
6506 		 * If we have the ownership then we just wait for an event
6507 		 * to happen (LDC reset), otherwise we will retry to recover
6508 		 * after a delay.
6509 		 */
6510 		if (vdc->ownership & VDC_OWNERSHIP_GRANTED)
6511 			timeout = 0;
6512 		else
6513 			timeout = ddi_get_lbolt() +
6514 			    drv_usectohz(vdc_ownership_delay);
6515 
6516 		/* Release the ownership_lock and wait on the vdc lock */
6517 		mutex_exit(&vdc->ownership_lock);
6518 
6519 		if (timeout == 0)
6520 			(void) cv_wait(&vdc->ownership_cv, &vdc->lock);
6521 		else
6522 			(void) cv_timedwait(&vdc->ownership_cv,
6523 			    &vdc->lock, timeout);
6524 
6525 		mutex_exit(&vdc->lock);
6526 
6527 		mutex_enter(&vdc->ownership_lock);
6528 		mutex_enter(&vdc->lock);
6529 	}
6530 
6531 	vdc->ownership_thread = NULL;
6532 	mutex_exit(&vdc->lock);
6533 	mutex_exit(&vdc->ownership_lock);
6534 
6535 	thread_exit();
6536 }
6537 
6538 static void
6539 vdc_ownership_update(vdc_t *vdc, int ownership_flags)
6540 {
6541 	ASSERT(MUTEX_HELD(&vdc->ownership_lock));
6542 
6543 	mutex_enter(&vdc->lock);
6544 	vdc->ownership = ownership_flags;
6545 	if ((vdc->ownership & VDC_OWNERSHIP_WANTED) &&
6546 	    vdc->ownership_thread == NULL) {
6547 		/* start ownership thread */
6548 		vdc->ownership_thread = thread_create(NULL, 0,
6549 		    vdc_ownership_thread, vdc, 0, &p0, TS_RUN,
6550 		    v.v_maxsyspri - 2);
6551 	} else {
6552 		/* notify the ownership thread */
6553 		cv_signal(&vdc->ownership_cv);
6554 	}
6555 	mutex_exit(&vdc->lock);
6556 }
6557 
6558 /*
6559  * Get the size and the block size of a virtual disk from the vdisk server.
6560  */
6561 static int
6562 vdc_get_capacity(vdc_t *vdc, size_t *dsk_size, size_t *blk_size)
6563 {
6564 	int rv = 0;
6565 	size_t alloc_len;
6566 	vd_capacity_t *vd_cap;
6567 
6568 	ASSERT(MUTEX_NOT_HELD(&vdc->lock));
6569 
6570 	alloc_len = P2ROUNDUP(sizeof (vd_capacity_t), sizeof (uint64_t));
6571 
6572 	vd_cap = kmem_zalloc(alloc_len, KM_SLEEP);
6573 
6574 	rv = vdc_do_sync_op(vdc, VD_OP_GET_CAPACITY, (caddr_t)vd_cap, alloc_len,
6575 	    0, 0, CB_SYNC, (void *)(uint64_t)FKIOCTL, VIO_both_dir, B_TRUE);
6576 
6577 	*dsk_size = vd_cap->vdisk_size;
6578 	*blk_size = vd_cap->vdisk_block_size;
6579 
6580 	kmem_free(vd_cap, alloc_len);
6581 	return (rv);
6582 }
6583 
6584 /*
6585  * Check the disk capacity. Disk size information is updated if size has
6586  * changed.
6587  *
6588  * Return 0 if the disk capacity is available, or non-zero if it is not.
6589  */
6590 static int
6591 vdc_check_capacity(vdc_t *vdc)
6592 {
6593 	size_t dsk_size, blk_size;
6594 	int rv;
6595 
6596 	/*
6597 	 * If the vdisk does not support the VD_OP_GET_CAPACITY operation
6598 	 * then the disk capacity has been retrieved during the handshake
6599 	 * and there's nothing more to do here.
6600 	 */
6601 	if (!VD_OP_SUPPORTED(vdc->operations, VD_OP_GET_CAPACITY))
6602 		return (0);
6603 
6604 	if ((rv = vdc_get_capacity(vdc, &dsk_size, &blk_size)) != 0)
6605 		return (rv);
6606 
6607 	if (dsk_size == VD_SIZE_UNKNOWN || dsk_size == 0)
6608 		return (EINVAL);
6609 
6610 	mutex_enter(&vdc->lock);
6611 	vdc_update_size(vdc, dsk_size, blk_size, vdc->max_xfer_sz);
6612 	mutex_exit(&vdc->lock);
6613 
6614 	return (0);
6615 }
6616 
6617 /*
6618  * This structure is used in the DKIO(7I) array below.
6619  */
6620 typedef struct vdc_dk_ioctl {
6621 	uint8_t		op;		/* VD_OP_XXX value */
6622 	int		cmd;		/* Solaris ioctl operation number */
6623 	size_t		nbytes;		/* size of structure to be copied */
6624 
6625 	/* function to convert between vDisk and Solaris structure formats */
6626 	int	(*convert)(vdc_t *vdc, void *vd_buf, void *ioctl_arg,
6627 	    int mode, int dir);
6628 } vdc_dk_ioctl_t;
6629 
6630 /*
6631  * Subset of DKIO(7I) operations currently supported
6632  */
6633 static vdc_dk_ioctl_t	dk_ioctl[] = {
6634 	{VD_OP_FLUSH,		DKIOCFLUSHWRITECACHE,	0,
6635 		vdc_null_copy_func},
6636 	{VD_OP_GET_WCE,		DKIOCGETWCE,		sizeof (int),
6637 		vdc_get_wce_convert},
6638 	{VD_OP_SET_WCE,		DKIOCSETWCE,		sizeof (int),
6639 		vdc_set_wce_convert},
6640 	{VD_OP_GET_VTOC,	DKIOCGVTOC,		sizeof (vd_vtoc_t),
6641 		vdc_get_vtoc_convert},
6642 	{VD_OP_SET_VTOC,	DKIOCSVTOC,		sizeof (vd_vtoc_t),
6643 		vdc_set_vtoc_convert},
6644 	{VD_OP_GET_VTOC,	DKIOCGEXTVTOC,		sizeof (vd_vtoc_t),
6645 		vdc_get_extvtoc_convert},
6646 	{VD_OP_SET_VTOC,	DKIOCSEXTVTOC,		sizeof (vd_vtoc_t),
6647 		vdc_set_extvtoc_convert},
6648 	{VD_OP_GET_DISKGEOM,	DKIOCGGEOM,		sizeof (vd_geom_t),
6649 		vdc_get_geom_convert},
6650 	{VD_OP_GET_DISKGEOM,	DKIOCG_PHYGEOM,		sizeof (vd_geom_t),
6651 		vdc_get_geom_convert},
6652 	{VD_OP_GET_DISKGEOM, 	DKIOCG_VIRTGEOM,	sizeof (vd_geom_t),
6653 		vdc_get_geom_convert},
6654 	{VD_OP_SET_DISKGEOM,	DKIOCSGEOM,		sizeof (vd_geom_t),
6655 		vdc_set_geom_convert},
6656 	{VD_OP_GET_EFI,		DKIOCGETEFI,		0,
6657 		vdc_get_efi_convert},
6658 	{VD_OP_SET_EFI,		DKIOCSETEFI,		0,
6659 		vdc_set_efi_convert},
6660 
6661 	/* DIOCTL_RWCMD is converted to a read or a write */
6662 	{0, DIOCTL_RWCMD,  sizeof (struct dadkio_rwcmd), NULL},
6663 
6664 	/* mhd(7I) non-shared multihost disks ioctls */
6665 	{0, MHIOCTKOWN,				0, vdc_null_copy_func},
6666 	{0, MHIOCRELEASE,			0, vdc_null_copy_func},
6667 	{0, MHIOCSTATUS,			0, vdc_null_copy_func},
6668 	{0, MHIOCQRESERVE,			0, vdc_null_copy_func},
6669 
6670 	/* mhd(7I) shared multihost disks ioctls */
6671 	{0, MHIOCGRP_INKEYS,			0, vdc_null_copy_func},
6672 	{0, MHIOCGRP_INRESV,			0, vdc_null_copy_func},
6673 	{0, MHIOCGRP_REGISTER,			0, vdc_null_copy_func},
6674 	{0, MHIOCGRP_RESERVE, 			0, vdc_null_copy_func},
6675 	{0, MHIOCGRP_PREEMPTANDABORT,		0, vdc_null_copy_func},
6676 	{0, MHIOCGRP_REGISTERANDIGNOREKEY,	0, vdc_null_copy_func},
6677 
6678 	/* mhd(7I) failfast ioctl */
6679 	{0, MHIOCENFAILFAST,			0, vdc_null_copy_func},
6680 
6681 	/*
6682 	 * These particular ioctls are not sent to the server - vdc fakes up
6683 	 * the necessary info.
6684 	 */
6685 	{0, DKIOCINFO, sizeof (struct dk_cinfo), vdc_null_copy_func},
6686 	{0, DKIOCGMEDIAINFO, sizeof (struct dk_minfo), vdc_null_copy_func},
6687 	{0, USCSICMD,	sizeof (struct uscsi_cmd), vdc_null_copy_func},
6688 	{0, DKIOCPARTITION, 0, vdc_null_copy_func },
6689 	{0, DKIOCGAPART, 0, vdc_null_copy_func },
6690 	{0, DKIOCREMOVABLE, 0, vdc_null_copy_func},
6691 	{0, CDROMREADOFFSET, 0, vdc_null_copy_func}
6692 };
6693 
6694 /*
6695  * This function handles ioctl requests from the vd_efi_alloc_and_read()
6696  * function and forward them to the vdisk.
6697  */
6698 static int
6699 vd_process_efi_ioctl(void *vdisk, int cmd, uintptr_t arg)
6700 {
6701 	vdc_t *vdc = (vdc_t *)vdisk;
6702 	dev_t dev;
6703 	int rval;
6704 
6705 	dev = makedevice(ddi_driver_major(vdc->dip),
6706 	    VD_MAKE_DEV(vdc->instance, 0));
6707 
6708 	return (vd_process_ioctl(dev, cmd, (caddr_t)arg, FKIOCTL, &rval));
6709 }
6710 
6711 /*
6712  * Function:
6713  *	vd_process_ioctl()
6714  *
6715  * Description:
6716  *	This routine processes disk specific ioctl calls
6717  *
6718  * Arguments:
6719  *	dev	- the device number
6720  *	cmd	- the operation [dkio(7I)] to be processed
6721  *	arg	- pointer to user provided structure
6722  *		  (contains data to be set or reference parameter for get)
6723  *	mode	- bit flag, indicating open settings, 32/64 bit type, etc
6724  *	rvalp	- pointer to return value for calling process.
6725  *
6726  * Return Code:
6727  *	0
6728  *	EFAULT
6729  *	ENXIO
6730  *	EIO
6731  *	ENOTSUP
6732  */
6733 static int
6734 vd_process_ioctl(dev_t dev, int cmd, caddr_t arg, int mode, int *rvalp)
6735 {
6736 	int		instance = VDCUNIT(dev);
6737 	vdc_t		*vdc = NULL;
6738 	int		rv = -1;
6739 	int		idx = 0;		/* index into dk_ioctl[] */
6740 	size_t		len = 0;		/* #bytes to send to vds */
6741 	size_t		alloc_len = 0;		/* #bytes to allocate mem for */
6742 	caddr_t		mem_p = NULL;
6743 	size_t		nioctls = (sizeof (dk_ioctl)) / (sizeof (dk_ioctl[0]));
6744 	vdc_dk_ioctl_t	*iop;
6745 
6746 	vdc = ddi_get_soft_state(vdc_state, instance);
6747 	if (vdc == NULL) {
6748 		cmn_err(CE_NOTE, "![%d] Could not get soft state structure",
6749 		    instance);
6750 		return (ENXIO);
6751 	}
6752 
6753 	DMSG(vdc, 0, "[%d] Processing ioctl(%x) for dev %lx : model %x\n",
6754 	    instance, cmd, dev, ddi_model_convert_from(mode & FMODELS));
6755 
6756 	if (rvalp != NULL) {
6757 		/* the return value of the ioctl is 0 by default */
6758 		*rvalp = 0;
6759 	}
6760 
6761 	/*
6762 	 * Validate the ioctl operation to be performed.
6763 	 *
6764 	 * If we have looped through the array without finding a match then we
6765 	 * don't support this ioctl.
6766 	 */
6767 	for (idx = 0; idx < nioctls; idx++) {
6768 		if (cmd == dk_ioctl[idx].cmd)
6769 			break;
6770 	}
6771 
6772 	if (idx >= nioctls) {
6773 		DMSG(vdc, 0, "[%d] Unsupported ioctl (0x%x)\n",
6774 		    vdc->instance, cmd);
6775 		return (ENOTSUP);
6776 	}
6777 
6778 	iop = &(dk_ioctl[idx]);
6779 
6780 	if (cmd == DKIOCGETEFI || cmd == DKIOCSETEFI) {
6781 		/* size is not fixed for EFI ioctls, it depends on ioctl arg */
6782 		dk_efi_t	dk_efi;
6783 
6784 		rv = ddi_copyin(arg, &dk_efi, sizeof (dk_efi_t), mode);
6785 		if (rv != 0)
6786 			return (EFAULT);
6787 
6788 		len = sizeof (vd_efi_t) - 1 + dk_efi.dki_length;
6789 	} else {
6790 		len = iop->nbytes;
6791 	}
6792 
6793 	/* check if the ioctl is applicable */
6794 	switch (cmd) {
6795 	case CDROMREADOFFSET:
6796 	case DKIOCREMOVABLE:
6797 		return (ENOTTY);
6798 
6799 	case USCSICMD:
6800 	case MHIOCTKOWN:
6801 	case MHIOCSTATUS:
6802 	case MHIOCQRESERVE:
6803 	case MHIOCRELEASE:
6804 	case MHIOCGRP_INKEYS:
6805 	case MHIOCGRP_INRESV:
6806 	case MHIOCGRP_REGISTER:
6807 	case MHIOCGRP_RESERVE:
6808 	case MHIOCGRP_PREEMPTANDABORT:
6809 	case MHIOCGRP_REGISTERANDIGNOREKEY:
6810 	case MHIOCENFAILFAST:
6811 		if (vdc->cinfo == NULL)
6812 			return (ENXIO);
6813 		if (vdc->cinfo->dki_ctype != DKC_SCSI_CCS)
6814 			return (ENOTTY);
6815 		break;
6816 
6817 	case DIOCTL_RWCMD:
6818 		if (vdc->cinfo == NULL)
6819 			return (ENXIO);
6820 		if (vdc->cinfo->dki_ctype != DKC_DIRECT)
6821 			return (ENOTTY);
6822 		break;
6823 
6824 	case DKIOCINFO:
6825 		if (vdc->cinfo == NULL)
6826 			return (ENXIO);
6827 		break;
6828 
6829 	case DKIOCGMEDIAINFO:
6830 		if (vdc->minfo == NULL)
6831 			return (ENXIO);
6832 		if (vdc_check_capacity(vdc) != 0)
6833 			/* disk capacity is not available */
6834 			return (EIO);
6835 		break;
6836 	}
6837 
6838 	/*
6839 	 * Deal with ioctls which require a processing different than
6840 	 * converting ioctl arguments and sending a corresponding
6841 	 * VD operation.
6842 	 */
6843 	switch (cmd) {
6844 
6845 	case USCSICMD:
6846 	{
6847 		return (vdc_uscsi_cmd(vdc, arg, mode));
6848 	}
6849 
6850 	case MHIOCTKOWN:
6851 	{
6852 		mutex_enter(&vdc->ownership_lock);
6853 		/*
6854 		 * We have to set VDC_OWNERSHIP_WANTED now so that the ownership
6855 		 * can be flagged with VDC_OWNERSHIP_RESET if the LDC is reset
6856 		 * while we are processing the ioctl.
6857 		 */
6858 		vdc_ownership_update(vdc, VDC_OWNERSHIP_WANTED);
6859 
6860 		rv = vdc_access_set(vdc, VD_ACCESS_SET_EXCLUSIVE |
6861 		    VD_ACCESS_SET_PREEMPT | VD_ACCESS_SET_PRESERVE, mode);
6862 		if (rv == 0) {
6863 			vdc_ownership_update(vdc, VDC_OWNERSHIP_WANTED |
6864 			    VDC_OWNERSHIP_GRANTED);
6865 		} else {
6866 			vdc_ownership_update(vdc, VDC_OWNERSHIP_NONE);
6867 		}
6868 		mutex_exit(&vdc->ownership_lock);
6869 		return (rv);
6870 	}
6871 
6872 	case MHIOCRELEASE:
6873 	{
6874 		mutex_enter(&vdc->ownership_lock);
6875 		rv = vdc_access_set(vdc, VD_ACCESS_SET_CLEAR, mode);
6876 		if (rv == 0) {
6877 			vdc_ownership_update(vdc, VDC_OWNERSHIP_NONE);
6878 		}
6879 		mutex_exit(&vdc->ownership_lock);
6880 		return (rv);
6881 	}
6882 
6883 	case MHIOCSTATUS:
6884 	{
6885 		uint64_t status;
6886 
6887 		rv = vdc_access_get(vdc, &status, mode);
6888 		if (rv == 0 && rvalp != NULL)
6889 			*rvalp = (status & VD_ACCESS_ALLOWED)? 0 : 1;
6890 		return (rv);
6891 	}
6892 
6893 	case MHIOCQRESERVE:
6894 	{
6895 		rv = vdc_access_set(vdc, VD_ACCESS_SET_EXCLUSIVE, mode);
6896 		return (rv);
6897 	}
6898 
6899 	case MHIOCGRP_INKEYS:
6900 	{
6901 		return (vdc_mhd_inkeys(vdc, arg, mode));
6902 	}
6903 
6904 	case MHIOCGRP_INRESV:
6905 	{
6906 		return (vdc_mhd_inresv(vdc, arg, mode));
6907 	}
6908 
6909 	case MHIOCGRP_REGISTER:
6910 	{
6911 		return (vdc_mhd_register(vdc, arg, mode));
6912 	}
6913 
6914 	case MHIOCGRP_RESERVE:
6915 	{
6916 		return (vdc_mhd_reserve(vdc, arg, mode));
6917 	}
6918 
6919 	case MHIOCGRP_PREEMPTANDABORT:
6920 	{
6921 		return (vdc_mhd_preemptabort(vdc, arg, mode));
6922 	}
6923 
6924 	case MHIOCGRP_REGISTERANDIGNOREKEY:
6925 	{
6926 		return (vdc_mhd_registerignore(vdc, arg, mode));
6927 	}
6928 
6929 	case MHIOCENFAILFAST:
6930 	{
6931 		rv = vdc_failfast(vdc, arg, mode);
6932 		return (rv);
6933 	}
6934 
6935 	case DIOCTL_RWCMD:
6936 	{
6937 		return (vdc_dioctl_rwcmd(dev, arg, mode));
6938 	}
6939 
6940 	case DKIOCGAPART:
6941 	{
6942 		return (vdc_dkio_gapart(vdc, arg, mode));
6943 	}
6944 
6945 	case DKIOCPARTITION:
6946 	{
6947 		return (vdc_dkio_partition(vdc, arg, mode));
6948 	}
6949 
6950 	case DKIOCINFO:
6951 	{
6952 		struct dk_cinfo	cinfo;
6953 
6954 		bcopy(vdc->cinfo, &cinfo, sizeof (struct dk_cinfo));
6955 		cinfo.dki_partition = VDCPART(dev);
6956 
6957 		rv = ddi_copyout(&cinfo, (void *)arg,
6958 		    sizeof (struct dk_cinfo), mode);
6959 		if (rv != 0)
6960 			return (EFAULT);
6961 
6962 		return (0);
6963 	}
6964 
6965 	case DKIOCGMEDIAINFO:
6966 	{
6967 		ASSERT(vdc->vdisk_size != 0);
6968 		ASSERT(vdc->minfo->dki_capacity != 0);
6969 		rv = ddi_copyout(vdc->minfo, (void *)arg,
6970 		    sizeof (struct dk_minfo), mode);
6971 		if (rv != 0)
6972 			return (EFAULT);
6973 
6974 		return (0);
6975 	}
6976 
6977 	case DKIOCFLUSHWRITECACHE:
6978 		{
6979 			struct dk_callback *dkc =
6980 			    (struct dk_callback *)(uintptr_t)arg;
6981 			vdc_dk_arg_t	*dkarg = NULL;
6982 
6983 			DMSG(vdc, 1, "[%d] Flush W$: mode %x\n",
6984 			    instance, mode);
6985 
6986 			/*
6987 			 * If arg is NULL, then there is no callback function
6988 			 * registered and the call operates synchronously; we
6989 			 * break and continue with the rest of the function and
6990 			 * wait for vds to return (i.e. after the request to
6991 			 * vds returns successfully, all writes completed prior
6992 			 * to the ioctl will have been flushed from the disk
6993 			 * write cache to persistent media.
6994 			 *
6995 			 * If a callback function is registered, we dispatch
6996 			 * the request on a task queue and return immediately.
6997 			 * The callback will deal with informing the calling
6998 			 * thread that the flush request is completed.
6999 			 */
7000 			if (dkc == NULL)
7001 				break;
7002 
7003 			/*
7004 			 * the asynchronous callback is only supported if
7005 			 * invoked from within the kernel
7006 			 */
7007 			if ((mode & FKIOCTL) == 0)
7008 				return (ENOTSUP);
7009 
7010 			dkarg = kmem_zalloc(sizeof (vdc_dk_arg_t), KM_SLEEP);
7011 
7012 			dkarg->mode = mode;
7013 			dkarg->dev = dev;
7014 			bcopy(dkc, &dkarg->dkc, sizeof (*dkc));
7015 
7016 			mutex_enter(&vdc->lock);
7017 			vdc->dkio_flush_pending++;
7018 			dkarg->vdc = vdc;
7019 			mutex_exit(&vdc->lock);
7020 
7021 			/* put the request on a task queue */
7022 			rv = taskq_dispatch(system_taskq, vdc_dkio_flush_cb,
7023 			    (void *)dkarg, DDI_SLEEP);
7024 			if (rv == NULL) {
7025 				/* clean up if dispatch fails */
7026 				mutex_enter(&vdc->lock);
7027 				vdc->dkio_flush_pending--;
7028 				mutex_exit(&vdc->lock);
7029 				kmem_free(dkarg, sizeof (vdc_dk_arg_t));
7030 			}
7031 
7032 			return (rv == NULL ? ENOMEM : 0);
7033 		}
7034 	}
7035 
7036 	/* catch programming error in vdc - should be a VD_OP_XXX ioctl */
7037 	ASSERT(iop->op != 0);
7038 
7039 	/* check if the vDisk server handles the operation for this vDisk */
7040 	if (VD_OP_SUPPORTED(vdc->operations, iop->op) == B_FALSE) {
7041 		DMSG(vdc, 0, "[%d] Unsupported VD_OP operation (0x%x)\n",
7042 		    vdc->instance, iop->op);
7043 		return (ENOTSUP);
7044 	}
7045 
7046 	/* LDC requires that the memory being mapped is 8-byte aligned */
7047 	alloc_len = P2ROUNDUP(len, sizeof (uint64_t));
7048 	DMSG(vdc, 1, "[%d] struct size %ld alloc %ld\n",
7049 	    instance, len, alloc_len);
7050 
7051 	if (alloc_len > 0)
7052 		mem_p = kmem_zalloc(alloc_len, KM_SLEEP);
7053 
7054 	/*
7055 	 * Call the conversion function for this ioctl which, if necessary,
7056 	 * converts from the Solaris format to the format ARC'ed
7057 	 * as part of the vDisk protocol (FWARC 2006/195)
7058 	 */
7059 	ASSERT(iop->convert != NULL);
7060 	rv = (iop->convert)(vdc, arg, mem_p, mode, VD_COPYIN);
7061 	if (rv != 0) {
7062 		DMSG(vdc, 0, "[%d] convert func returned %d for ioctl 0x%x\n",
7063 		    instance, rv, cmd);
7064 		if (mem_p != NULL)
7065 			kmem_free(mem_p, alloc_len);
7066 		return (rv);
7067 	}
7068 
7069 	/*
7070 	 * send request to vds to service the ioctl.
7071 	 */
7072 	rv = vdc_do_sync_op(vdc, iop->op, mem_p, alloc_len,
7073 	    VDCPART(dev), 0, CB_SYNC, (void *)(uint64_t)mode,
7074 	    VIO_both_dir, B_TRUE);
7075 
7076 	if (rv != 0) {
7077 		/*
7078 		 * This is not necessarily an error. The ioctl could
7079 		 * be returning a value such as ENOTTY to indicate
7080 		 * that the ioctl is not applicable.
7081 		 */
7082 		DMSG(vdc, 0, "[%d] vds returned %d for ioctl 0x%x\n",
7083 		    instance, rv, cmd);
7084 		if (mem_p != NULL)
7085 			kmem_free(mem_p, alloc_len);
7086 
7087 		return (rv);
7088 	}
7089 
7090 	/*
7091 	 * Call the conversion function (if it exists) for this ioctl
7092 	 * which converts from the format ARC'ed as part of the vDisk
7093 	 * protocol (FWARC 2006/195) back to a format understood by
7094 	 * the rest of Solaris.
7095 	 */
7096 	rv = (iop->convert)(vdc, mem_p, arg, mode, VD_COPYOUT);
7097 	if (rv != 0) {
7098 		DMSG(vdc, 0, "[%d] convert func returned %d for ioctl 0x%x\n",
7099 		    instance, rv, cmd);
7100 		if (mem_p != NULL)
7101 			kmem_free(mem_p, alloc_len);
7102 		return (rv);
7103 	}
7104 
7105 	if (mem_p != NULL)
7106 		kmem_free(mem_p, alloc_len);
7107 
7108 	return (rv);
7109 }
7110 
7111 /*
7112  * Function:
7113  *
7114  * Description:
7115  *	This is an empty conversion function used by ioctl calls which
7116  *	do not need to convert the data being passed in/out to userland
7117  */
7118 static int
7119 vdc_null_copy_func(vdc_t *vdc, void *from, void *to, int mode, int dir)
7120 {
7121 	_NOTE(ARGUNUSED(vdc))
7122 	_NOTE(ARGUNUSED(from))
7123 	_NOTE(ARGUNUSED(to))
7124 	_NOTE(ARGUNUSED(mode))
7125 	_NOTE(ARGUNUSED(dir))
7126 
7127 	return (0);
7128 }
7129 
7130 static int
7131 vdc_get_wce_convert(vdc_t *vdc, void *from, void *to,
7132     int mode, int dir)
7133 {
7134 	_NOTE(ARGUNUSED(vdc))
7135 
7136 	if (dir == VD_COPYIN)
7137 		return (0);		/* nothing to do */
7138 
7139 	if (ddi_copyout(from, to, sizeof (int), mode) != 0)
7140 		return (EFAULT);
7141 
7142 	return (0);
7143 }
7144 
7145 static int
7146 vdc_set_wce_convert(vdc_t *vdc, void *from, void *to,
7147     int mode, int dir)
7148 {
7149 	_NOTE(ARGUNUSED(vdc))
7150 
7151 	if (dir == VD_COPYOUT)
7152 		return (0);		/* nothing to do */
7153 
7154 	if (ddi_copyin(from, to, sizeof (int), mode) != 0)
7155 		return (EFAULT);
7156 
7157 	return (0);
7158 }
7159 
7160 /*
7161  * Function:
7162  *	vdc_get_vtoc_convert()
7163  *
7164  * Description:
7165  *	This routine performs the necessary convertions from the DKIOCGVTOC
7166  *	Solaris structure to the format defined in FWARC 2006/195.
7167  *
7168  *	In the struct vtoc definition, the timestamp field is marked as not
7169  *	supported so it is not part of vDisk protocol (FWARC 2006/195).
7170  *	However SVM uses that field to check it can write into the VTOC,
7171  *	so we fake up the info of that field.
7172  *
7173  * Arguments:
7174  *	vdc	- the vDisk client
7175  *	from	- the buffer containing the data to be copied from
7176  *	to	- the buffer to be copied to
7177  *	mode	- flags passed to ioctl() call
7178  *	dir	- the "direction" of the copy - VD_COPYIN or VD_COPYOUT
7179  *
7180  * Return Code:
7181  *	0	- Success
7182  *	ENXIO	- incorrect buffer passed in.
7183  *	EFAULT	- ddi_copyout routine encountered an error.
7184  */
7185 static int
7186 vdc_get_vtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7187 {
7188 	int		i;
7189 	struct vtoc	vtoc;
7190 	struct vtoc32	vtoc32;
7191 	struct extvtoc	evtoc;
7192 	int		rv;
7193 
7194 	if (dir != VD_COPYOUT)
7195 		return (0);	/* nothing to do */
7196 
7197 	if ((from == NULL) || (to == NULL))
7198 		return (ENXIO);
7199 
7200 	if (vdc->vdisk_size > VD_OLDVTOC_LIMIT)
7201 		return (EOVERFLOW);
7202 
7203 	VD_VTOC2VTOC((vd_vtoc_t *)from, &evtoc);
7204 
7205 	/* fake the VTOC timestamp field */
7206 	for (i = 0; i < V_NUMPAR; i++) {
7207 		evtoc.timestamp[i] = vdc->vtoc->timestamp[i];
7208 	}
7209 
7210 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
7211 		/* LINTED E_ASSIGN_NARROW_CONV */
7212 		extvtoctovtoc32(evtoc, vtoc32);
7213 		rv = ddi_copyout(&vtoc32, to, sizeof (vtoc32), mode);
7214 		if (rv != 0)
7215 			rv = EFAULT;
7216 	} else {
7217 		extvtoctovtoc(evtoc, vtoc);
7218 		rv = ddi_copyout(&vtoc, to, sizeof (vtoc), mode);
7219 		if (rv != 0)
7220 			rv = EFAULT;
7221 	}
7222 
7223 	return (rv);
7224 }
7225 
7226 /*
7227  * Function:
7228  *	vdc_set_vtoc_convert()
7229  *
7230  * Description:
7231  *	This routine performs the necessary convertions from the DKIOCSVTOC
7232  *	Solaris structure to the format defined in FWARC 2006/195.
7233  *
7234  * Arguments:
7235  *	vdc	- the vDisk client
7236  *	from	- Buffer with data
7237  *	to	- Buffer where data is to be copied to
7238  *	mode	- flags passed to ioctl
7239  *	dir	- direction of copy (in or out)
7240  *
7241  * Return Code:
7242  *	0	- Success
7243  *	ENXIO	- Invalid buffer passed in
7244  *	EFAULT	- ddi_copyin of data failed
7245  */
7246 static int
7247 vdc_set_vtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7248 {
7249 	void		*uvtoc;
7250 	struct vtoc	vtoc;
7251 	struct vtoc32	vtoc32;
7252 	struct extvtoc	evtoc;
7253 	int		i, rv;
7254 
7255 	if ((from == NULL) || (to == NULL))
7256 		return (ENXIO);
7257 
7258 	if (vdc->vdisk_size > VD_OLDVTOC_LIMIT)
7259 		return (EOVERFLOW);
7260 
7261 	uvtoc = (dir == VD_COPYIN)? from : to;
7262 
7263 	if (ddi_model_convert_from(mode & FMODELS) == DDI_MODEL_ILP32) {
7264 		rv = ddi_copyin(uvtoc, &vtoc32, sizeof (vtoc32), mode);
7265 		if (rv != 0)
7266 			return (EFAULT);
7267 		vtoc32toextvtoc(vtoc32, evtoc);
7268 	} else {
7269 		rv = ddi_copyin(uvtoc, &vtoc, sizeof (vtoc), mode);
7270 		if (rv != 0)
7271 			return (EFAULT);
7272 		vtoctoextvtoc(vtoc, evtoc);
7273 	}
7274 
7275 	if (dir == VD_COPYOUT) {
7276 		/*
7277 		 * The disk label may have changed. Revalidate the disk
7278 		 * geometry. This will also update the device nodes.
7279 		 */
7280 		vdc_validate(vdc);
7281 
7282 		/*
7283 		 * We also need to keep track of the timestamp fields.
7284 		 */
7285 		for (i = 0; i < V_NUMPAR; i++) {
7286 			vdc->vtoc->timestamp[i] = evtoc.timestamp[i];
7287 		}
7288 
7289 	} else {
7290 		VTOC2VD_VTOC(&evtoc, (vd_vtoc_t *)to);
7291 	}
7292 
7293 	return (0);
7294 }
7295 
7296 static int
7297 vdc_get_extvtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7298 {
7299 	int		i, rv;
7300 	struct extvtoc	evtoc;
7301 
7302 	if (dir != VD_COPYOUT)
7303 		return (0);	/* nothing to do */
7304 
7305 	if ((from == NULL) || (to == NULL))
7306 		return (ENXIO);
7307 
7308 	VD_VTOC2VTOC((vd_vtoc_t *)from, &evtoc);
7309 
7310 	/* fake the VTOC timestamp field */
7311 	for (i = 0; i < V_NUMPAR; i++) {
7312 		evtoc.timestamp[i] = vdc->vtoc->timestamp[i];
7313 	}
7314 
7315 	rv = ddi_copyout(&evtoc, to, sizeof (struct extvtoc), mode);
7316 	if (rv != 0)
7317 		rv = EFAULT;
7318 
7319 	return (rv);
7320 }
7321 
7322 static int
7323 vdc_set_extvtoc_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7324 {
7325 	void		*uvtoc;
7326 	struct extvtoc	evtoc;
7327 	int		i, rv;
7328 
7329 	if ((from == NULL) || (to == NULL))
7330 		return (ENXIO);
7331 
7332 	uvtoc = (dir == VD_COPYIN)? from : to;
7333 
7334 	rv = ddi_copyin(uvtoc, &evtoc, sizeof (struct extvtoc), mode);
7335 	if (rv != 0)
7336 		return (EFAULT);
7337 
7338 	if (dir == VD_COPYOUT) {
7339 		/*
7340 		 * The disk label may have changed. Revalidate the disk
7341 		 * geometry. This will also update the device nodes.
7342 		 */
7343 		vdc_validate(vdc);
7344 
7345 		/*
7346 		 * We also need to keep track of the timestamp fields.
7347 		 */
7348 		for (i = 0; i < V_NUMPAR; i++) {
7349 			vdc->vtoc->timestamp[i] = evtoc.timestamp[i];
7350 		}
7351 
7352 	} else {
7353 		VTOC2VD_VTOC(&evtoc, (vd_vtoc_t *)to);
7354 	}
7355 
7356 	return (0);
7357 }
7358 
7359 /*
7360  * Function:
7361  *	vdc_get_geom_convert()
7362  *
7363  * Description:
7364  *	This routine performs the necessary convertions from the DKIOCGGEOM,
7365  *	DKIOCG_PHYSGEOM and DKIOG_VIRTGEOM Solaris structures to the format
7366  *	defined in FWARC 2006/195
7367  *
7368  * Arguments:
7369  *	vdc	- the vDisk client
7370  *	from	- Buffer with data
7371  *	to	- Buffer where data is to be copied to
7372  *	mode	- flags passed to ioctl
7373  *	dir	- direction of copy (in or out)
7374  *
7375  * Return Code:
7376  *	0	- Success
7377  *	ENXIO	- Invalid buffer passed in
7378  *	EFAULT	- ddi_copyout of data failed
7379  */
7380 static int
7381 vdc_get_geom_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7382 {
7383 	_NOTE(ARGUNUSED(vdc))
7384 
7385 	struct dk_geom	geom;
7386 	int	copy_len = sizeof (struct dk_geom);
7387 	int	rv = 0;
7388 
7389 	if (dir != VD_COPYOUT)
7390 		return (0);	/* nothing to do */
7391 
7392 	if ((from == NULL) || (to == NULL))
7393 		return (ENXIO);
7394 
7395 	VD_GEOM2DK_GEOM((vd_geom_t *)from, &geom);
7396 	rv = ddi_copyout(&geom, to, copy_len, mode);
7397 	if (rv != 0)
7398 		rv = EFAULT;
7399 
7400 	return (rv);
7401 }
7402 
7403 /*
7404  * Function:
7405  *	vdc_set_geom_convert()
7406  *
7407  * Description:
7408  *	This routine performs the necessary convertions from the DKIOCSGEOM
7409  *	Solaris structure to the format defined in FWARC 2006/195.
7410  *
7411  * Arguments:
7412  *	vdc	- the vDisk client
7413  *	from	- Buffer with data
7414  *	to	- Buffer where data is to be copied to
7415  *	mode	- flags passed to ioctl
7416  *	dir	- direction of copy (in or out)
7417  *
7418  * Return Code:
7419  *	0	- Success
7420  *	ENXIO	- Invalid buffer passed in
7421  *	EFAULT	- ddi_copyin of data failed
7422  */
7423 static int
7424 vdc_set_geom_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7425 {
7426 	_NOTE(ARGUNUSED(vdc))
7427 
7428 	vd_geom_t	vdgeom;
7429 	void		*tmp_mem = NULL;
7430 	int		copy_len = sizeof (struct dk_geom);
7431 	int		rv = 0;
7432 
7433 	if (dir != VD_COPYIN)
7434 		return (0);	/* nothing to do */
7435 
7436 	if ((from == NULL) || (to == NULL))
7437 		return (ENXIO);
7438 
7439 	tmp_mem = kmem_alloc(copy_len, KM_SLEEP);
7440 
7441 	rv = ddi_copyin(from, tmp_mem, copy_len, mode);
7442 	if (rv != 0) {
7443 		kmem_free(tmp_mem, copy_len);
7444 		return (EFAULT);
7445 	}
7446 	DK_GEOM2VD_GEOM((struct dk_geom *)tmp_mem, &vdgeom);
7447 	bcopy(&vdgeom, to, sizeof (vdgeom));
7448 	kmem_free(tmp_mem, copy_len);
7449 
7450 	return (0);
7451 }
7452 
7453 static int
7454 vdc_get_efi_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7455 {
7456 	_NOTE(ARGUNUSED(vdc))
7457 
7458 	vd_efi_t	*vd_efi;
7459 	dk_efi_t	dk_efi;
7460 	int		rv = 0;
7461 	void		*uaddr;
7462 
7463 	if ((from == NULL) || (to == NULL))
7464 		return (ENXIO);
7465 
7466 	if (dir == VD_COPYIN) {
7467 
7468 		vd_efi = (vd_efi_t *)to;
7469 
7470 		rv = ddi_copyin(from, &dk_efi, sizeof (dk_efi_t), mode);
7471 		if (rv != 0)
7472 			return (EFAULT);
7473 
7474 		vd_efi->lba = dk_efi.dki_lba;
7475 		vd_efi->length = dk_efi.dki_length;
7476 		bzero(vd_efi->data, vd_efi->length);
7477 
7478 	} else {
7479 
7480 		rv = ddi_copyin(to, &dk_efi, sizeof (dk_efi_t), mode);
7481 		if (rv != 0)
7482 			return (EFAULT);
7483 
7484 		uaddr = dk_efi.dki_data;
7485 
7486 		dk_efi.dki_data = kmem_alloc(dk_efi.dki_length, KM_SLEEP);
7487 
7488 		VD_EFI2DK_EFI((vd_efi_t *)from, &dk_efi);
7489 
7490 		rv = ddi_copyout(dk_efi.dki_data, uaddr, dk_efi.dki_length,
7491 		    mode);
7492 		if (rv != 0)
7493 			return (EFAULT);
7494 
7495 		kmem_free(dk_efi.dki_data, dk_efi.dki_length);
7496 	}
7497 
7498 	return (0);
7499 }
7500 
7501 static int
7502 vdc_set_efi_convert(vdc_t *vdc, void *from, void *to, int mode, int dir)
7503 {
7504 	_NOTE(ARGUNUSED(vdc))
7505 
7506 	dk_efi_t	dk_efi;
7507 	void		*uaddr;
7508 
7509 	if (dir == VD_COPYOUT) {
7510 		/*
7511 		 * The disk label may have changed. Revalidate the disk
7512 		 * geometry. This will also update the device nodes.
7513 		 */
7514 		vdc_validate(vdc);
7515 		return (0);
7516 	}
7517 
7518 	if ((from == NULL) || (to == NULL))
7519 		return (ENXIO);
7520 
7521 	if (ddi_copyin(from, &dk_efi, sizeof (dk_efi_t), mode) != 0)
7522 		return (EFAULT);
7523 
7524 	uaddr = dk_efi.dki_data;
7525 
7526 	dk_efi.dki_data = kmem_alloc(dk_efi.dki_length, KM_SLEEP);
7527 
7528 	if (ddi_copyin(uaddr, dk_efi.dki_data, dk_efi.dki_length, mode) != 0)
7529 		return (EFAULT);
7530 
7531 	DK_EFI2VD_EFI(&dk_efi, (vd_efi_t *)to);
7532 
7533 	kmem_free(dk_efi.dki_data, dk_efi.dki_length);
7534 
7535 	return (0);
7536 }
7537 
7538 
7539 /* -------------------------------------------------------------------------- */
7540 
7541 /*
7542  * Function:
7543  *	vdc_create_fake_geometry()
7544  *
7545  * Description:
7546  *	This routine fakes up the disk info needed for some DKIO ioctls such
7547  *	as DKIOCINFO and DKIOCGMEDIAINFO [just like lofi(7D) and ramdisk(7D) do]
7548  *
7549  *	Note: This function must not be called until the vDisk attributes have
7550  *	been exchanged as part of the handshake with the vDisk server.
7551  *
7552  * Arguments:
7553  *	vdc	- soft state pointer for this instance of the device driver.
7554  *
7555  * Return Code:
7556  *	none.
7557  */
7558 static void
7559 vdc_create_fake_geometry(vdc_t *vdc)
7560 {
7561 	ASSERT(vdc != NULL);
7562 	ASSERT(vdc->max_xfer_sz != 0);
7563 
7564 	/*
7565 	 * DKIOCINFO support
7566 	 */
7567 	if (vdc->cinfo == NULL)
7568 		vdc->cinfo = kmem_zalloc(sizeof (struct dk_cinfo), KM_SLEEP);
7569 
7570 	(void) strcpy(vdc->cinfo->dki_cname, VDC_DRIVER_NAME);
7571 	(void) strcpy(vdc->cinfo->dki_dname, VDC_DRIVER_NAME);
7572 	/* max_xfer_sz is #blocks so we don't need to divide by DEV_BSIZE */
7573 	vdc->cinfo->dki_maxtransfer = vdc->max_xfer_sz;
7574 
7575 	/*
7576 	 * We set the controller type to DKC_SCSI_CCS only if the VD_OP_SCSICMD
7577 	 * operation is supported, otherwise the controller type is DKC_DIRECT.
7578 	 * Version 1.0 does not support the VD_OP_SCSICMD operation, so the
7579 	 * controller type is always DKC_DIRECT in that case.
7580 	 *
7581 	 * If the virtual disk is backed by a physical CD/DVD device or
7582 	 * an ISO image, modify the controller type to indicate this
7583 	 */
7584 	switch (vdc->vdisk_media) {
7585 	case VD_MEDIA_CD:
7586 	case VD_MEDIA_DVD:
7587 		vdc->cinfo->dki_ctype = DKC_CDROM;
7588 		break;
7589 	case VD_MEDIA_FIXED:
7590 		if (VD_OP_SUPPORTED(vdc->operations, VD_OP_SCSICMD))
7591 			vdc->cinfo->dki_ctype = DKC_SCSI_CCS;
7592 		else
7593 			vdc->cinfo->dki_ctype = DKC_DIRECT;
7594 		break;
7595 	default:
7596 		/* in the case of v1.0 we default to a fixed disk */
7597 		vdc->cinfo->dki_ctype = DKC_DIRECT;
7598 		break;
7599 	}
7600 	vdc->cinfo->dki_flags = DKI_FMTVOL;
7601 	vdc->cinfo->dki_cnum = 0;
7602 	vdc->cinfo->dki_addr = 0;
7603 	vdc->cinfo->dki_space = 0;
7604 	vdc->cinfo->dki_prio = 0;
7605 	vdc->cinfo->dki_vec = 0;
7606 	vdc->cinfo->dki_unit = vdc->instance;
7607 	vdc->cinfo->dki_slave = 0;
7608 	/*
7609 	 * The partition number will be created on the fly depending on the
7610 	 * actual slice (i.e. minor node) that is used to request the data.
7611 	 */
7612 	vdc->cinfo->dki_partition = 0;
7613 
7614 	/*
7615 	 * DKIOCGMEDIAINFO support
7616 	 */
7617 	if (vdc->minfo == NULL)
7618 		vdc->minfo = kmem_zalloc(sizeof (struct dk_minfo), KM_SLEEP);
7619 
7620 	if (vio_ver_is_supported(vdc->ver, 1, 1)) {
7621 		vdc->minfo->dki_media_type =
7622 		    VD_MEDIATYPE2DK_MEDIATYPE(vdc->vdisk_media);
7623 	} else {
7624 		vdc->minfo->dki_media_type = DK_FIXED_DISK;
7625 	}
7626 
7627 	vdc->minfo->dki_capacity = vdc->vdisk_size;
7628 	vdc->minfo->dki_lbsize = vdc->block_size;
7629 }
7630 
7631 static ushort_t
7632 vdc_lbl2cksum(struct dk_label *label)
7633 {
7634 	int	count;
7635 	ushort_t sum, *sp;
7636 
7637 	count =	(sizeof (struct dk_label)) / (sizeof (short)) - 1;
7638 	sp = (ushort_t *)label;
7639 	sum = 0;
7640 	while (count--) {
7641 		sum ^= *sp++;
7642 	}
7643 
7644 	return (sum);
7645 }
7646 
7647 static void
7648 vdc_update_size(vdc_t *vdc, size_t dsk_size, size_t blk_size, size_t xfr_size)
7649 {
7650 	vd_err_stats_t  *stp;
7651 
7652 	ASSERT(MUTEX_HELD(&vdc->lock));
7653 	ASSERT(xfr_size != 0);
7654 
7655 	/*
7656 	 * If the disk size is unknown or sizes are unchanged then don't
7657 	 * update anything.
7658 	 */
7659 	if (dsk_size == VD_SIZE_UNKNOWN || dsk_size == 0 ||
7660 	    (blk_size == vdc->block_size && dsk_size == vdc->vdisk_size &&
7661 	    xfr_size == vdc->max_xfer_sz))
7662 		return;
7663 
7664 	/*
7665 	 * We don't know at compile time what the vDisk server will think
7666 	 * are good values but we apply a large (arbitrary) upper bound to
7667 	 * prevent memory exhaustion in vdc if it was allocating a DRing
7668 	 * based of huge values sent by the server. We probably will never
7669 	 * exceed this except if the message was garbage.
7670 	 */
7671 	if ((xfr_size * blk_size) > (PAGESIZE * DEV_BSIZE)) {
7672 		DMSG(vdc, 0, "[%d] vds block transfer size too big;"
7673 		    " using max supported by vdc", vdc->instance);
7674 		xfr_size = maxphys / DEV_BSIZE;
7675 		dsk_size = (dsk_size * blk_size) / DEV_BSIZE;
7676 		blk_size = DEV_BSIZE;
7677 	}
7678 
7679 	vdc->max_xfer_sz = xfr_size;
7680 	vdc->block_size = blk_size;
7681 	vdc->vdisk_size = dsk_size;
7682 
7683 	stp = (vd_err_stats_t *)vdc->err_stats->ks_data;
7684 	stp->vd_capacity.value.ui64 = dsk_size * blk_size;
7685 
7686 	vdc->minfo->dki_capacity = dsk_size;
7687 	vdc->minfo->dki_lbsize = (uint_t)blk_size;
7688 }
7689 
7690 /*
7691  * Function:
7692  *	vdc_validate_geometry
7693  *
7694  * Description:
7695  *	This routine discovers the label and geometry of the disk. It stores
7696  *	the disk label and related information in the vdc structure. If it
7697  *	fails to validate the geometry or to discover the disk label then
7698  *	the label is marked as unknown (VD_DISK_LABEL_UNK).
7699  *
7700  * Arguments:
7701  *	vdc	- soft state pointer for this instance of the device driver.
7702  *
7703  * Return Code:
7704  *	0	- success.
7705  *	EINVAL	- unknown disk label.
7706  *	ENOTSUP	- geometry not applicable (EFI label).
7707  *	EIO	- error accessing the disk.
7708  */
7709 static int
7710 vdc_validate_geometry(vdc_t *vdc)
7711 {
7712 	buf_t	*buf;	/* BREAD requests need to be in a buf_t structure */
7713 	dev_t	dev;
7714 	int	rv, rval;
7715 	struct dk_label label;
7716 	struct dk_geom geom;
7717 	struct extvtoc vtoc;
7718 	efi_gpt_t *gpt;
7719 	efi_gpe_t *gpe;
7720 	vd_efi_dev_t edev;
7721 
7722 	ASSERT(vdc != NULL);
7723 	ASSERT(vdc->vtoc != NULL && vdc->geom != NULL);
7724 	ASSERT(MUTEX_HELD(&vdc->lock));
7725 
7726 	mutex_exit(&vdc->lock);
7727 	/*
7728 	 * Check the disk capacity in case it has changed. If that fails then
7729 	 * we proceed and we will be using the disk size we currently have.
7730 	 */
7731 	(void) vdc_check_capacity(vdc);
7732 	dev = makedevice(ddi_driver_major(vdc->dip),
7733 	    VD_MAKE_DEV(vdc->instance, 0));
7734 
7735 	rv = vd_process_ioctl(dev, DKIOCGGEOM, (caddr_t)&geom, FKIOCTL, &rval);
7736 	if (rv == 0)
7737 		rv = vd_process_ioctl(dev, DKIOCGEXTVTOC, (caddr_t)&vtoc,
7738 		    FKIOCTL, &rval);
7739 
7740 	if (rv == ENOTSUP) {
7741 		/*
7742 		 * If the device does not support VTOC then we try
7743 		 * to read an EFI label.
7744 		 *
7745 		 * We need to know the block size and the disk size to
7746 		 * be able to read an EFI label.
7747 		 */
7748 		if (vdc->vdisk_size == 0) {
7749 			mutex_enter(&vdc->lock);
7750 			vdc_store_label_unk(vdc);
7751 			return (EIO);
7752 		}
7753 
7754 		VD_EFI_DEV_SET(edev, vdc, vd_process_efi_ioctl);
7755 
7756 		rv = vd_efi_alloc_and_read(&edev, &gpt, &gpe);
7757 
7758 		if (rv) {
7759 			DMSG(vdc, 0, "[%d] Failed to get EFI (err=%d)",
7760 			    vdc->instance, rv);
7761 			mutex_enter(&vdc->lock);
7762 			vdc_store_label_unk(vdc);
7763 			return (EIO);
7764 		}
7765 
7766 		mutex_enter(&vdc->lock);
7767 		vdc_store_label_efi(vdc, gpt, gpe);
7768 		vd_efi_free(&edev, gpt, gpe);
7769 		return (ENOTSUP);
7770 	}
7771 
7772 	if (rv != 0) {
7773 		DMSG(vdc, 0, "[%d] Failed to get VTOC (err=%d)",
7774 		    vdc->instance, rv);
7775 		mutex_enter(&vdc->lock);
7776 		vdc_store_label_unk(vdc);
7777 		if (rv != EINVAL)
7778 			rv = EIO;
7779 		return (rv);
7780 	}
7781 
7782 	/* check that geometry and vtoc are valid */
7783 	if (geom.dkg_nhead == 0 || geom.dkg_nsect == 0 ||
7784 	    vtoc.v_sanity != VTOC_SANE) {
7785 		mutex_enter(&vdc->lock);
7786 		vdc_store_label_unk(vdc);
7787 		return (EINVAL);
7788 	}
7789 
7790 	/*
7791 	 * We have a disk and a valid VTOC. However this does not mean
7792 	 * that the disk currently have a VTOC label. The returned VTOC may
7793 	 * be a default VTOC to be used for configuring the disk (this is
7794 	 * what is done for disk image). So we read the label from the
7795 	 * beginning of the disk to ensure we really have a VTOC label.
7796 	 *
7797 	 * FUTURE: This could be the default way for reading the VTOC
7798 	 * from the disk as opposed to sending the VD_OP_GET_VTOC
7799 	 * to the server. This will be the default if vdc is implemented
7800 	 * ontop of cmlb.
7801 	 */
7802 
7803 	/*
7804 	 * Single slice disk does not support read using an absolute disk
7805 	 * offset so we just rely on the DKIOCGVTOC ioctl in that case.
7806 	 */
7807 	if (vdc->vdisk_type == VD_DISK_TYPE_SLICE) {
7808 		mutex_enter(&vdc->lock);
7809 		if (vtoc.v_nparts != 1) {
7810 			vdc_store_label_unk(vdc);
7811 			return (EINVAL);
7812 		}
7813 		vdc_store_label_vtoc(vdc, &geom, &vtoc);
7814 		return (0);
7815 	}
7816 
7817 	if (vtoc.v_nparts != V_NUMPAR) {
7818 		mutex_enter(&vdc->lock);
7819 		vdc_store_label_unk(vdc);
7820 		return (EINVAL);
7821 	}
7822 
7823 	/*
7824 	 * Read disk label from start of disk
7825 	 */
7826 	buf = kmem_alloc(sizeof (buf_t), KM_SLEEP);
7827 	bioinit(buf);
7828 	buf->b_un.b_addr = (caddr_t)&label;
7829 	buf->b_bcount = DK_LABEL_SIZE;
7830 	buf->b_flags = B_BUSY | B_READ;
7831 	buf->b_dev = cmpdev(dev);
7832 	rv = vdc_send_request(vdc, VD_OP_BREAD, (caddr_t)&label,
7833 	    DK_LABEL_SIZE, VD_SLICE_NONE, 0, CB_STRATEGY, buf, VIO_read_dir);
7834 	if (rv) {
7835 		DMSG(vdc, 1, "[%d] Failed to read disk block 0\n",
7836 		    vdc->instance);
7837 	} else {
7838 		rv = biowait(buf);
7839 		biofini(buf);
7840 	}
7841 	kmem_free(buf, sizeof (buf_t));
7842 
7843 	if (rv != 0 || label.dkl_magic != DKL_MAGIC ||
7844 	    label.dkl_cksum != vdc_lbl2cksum(&label)) {
7845 		DMSG(vdc, 1, "[%d] Got VTOC with invalid label\n",
7846 		    vdc->instance);
7847 		mutex_enter(&vdc->lock);
7848 		vdc_store_label_unk(vdc);
7849 		return (EINVAL);
7850 	}
7851 
7852 	mutex_enter(&vdc->lock);
7853 	vdc_store_label_vtoc(vdc, &geom, &vtoc);
7854 	return (0);
7855 }
7856 
7857 /*
7858  * Function:
7859  *	vdc_validate
7860  *
7861  * Description:
7862  *	This routine discovers the label of the disk and create the
7863  *	appropriate device nodes if the label has changed.
7864  *
7865  * Arguments:
7866  *	vdc	- soft state pointer for this instance of the device driver.
7867  *
7868  * Return Code:
7869  *	none.
7870  */
7871 static void
7872 vdc_validate(vdc_t *vdc)
7873 {
7874 	vd_disk_label_t old_label;
7875 	vd_slice_t old_slice[V_NUMPAR];
7876 	int rv;
7877 
7878 	ASSERT(!MUTEX_HELD(&vdc->lock));
7879 
7880 	mutex_enter(&vdc->lock);
7881 
7882 	/* save the current label and vtoc */
7883 	old_label = vdc->vdisk_label;
7884 	bcopy(vdc->slice, &old_slice, sizeof (vd_slice_t) * V_NUMPAR);
7885 
7886 	/* check the geometry */
7887 	(void) vdc_validate_geometry(vdc);
7888 
7889 	/* if the disk label has changed, update device nodes */
7890 	if (vdc->vdisk_label != old_label) {
7891 
7892 		if (vdc->vdisk_label == VD_DISK_LABEL_EFI)
7893 			rv = vdc_create_device_nodes_efi(vdc);
7894 		else
7895 			rv = vdc_create_device_nodes_vtoc(vdc);
7896 
7897 		if (rv != 0) {
7898 			DMSG(vdc, 0, "![%d] Failed to update device nodes",
7899 			    vdc->instance);
7900 		}
7901 	}
7902 
7903 	mutex_exit(&vdc->lock);
7904 }
7905 
7906 static void
7907 vdc_validate_task(void *arg)
7908 {
7909 	vdc_t *vdc = (vdc_t *)arg;
7910 
7911 	vdc_validate(vdc);
7912 
7913 	mutex_enter(&vdc->lock);
7914 	ASSERT(vdc->validate_pending > 0);
7915 	vdc->validate_pending--;
7916 	mutex_exit(&vdc->lock);
7917 }
7918 
7919 /*
7920  * Function:
7921  *	vdc_setup_devid()
7922  *
7923  * Description:
7924  *	This routine discovers the devid of a vDisk. It requests the devid of
7925  *	the underlying device from the vDisk server, builds an encapsulated
7926  *	devid based on the retrieved devid and registers that new devid to
7927  *	the vDisk.
7928  *
7929  * Arguments:
7930  *	vdc	- soft state pointer for this instance of the device driver.
7931  *
7932  * Return Code:
7933  *	0	- A devid was succesfully registered for the vDisk
7934  */
7935 static int
7936 vdc_setup_devid(vdc_t *vdc)
7937 {
7938 	int rv;
7939 	vd_devid_t *vd_devid;
7940 	size_t bufsize, bufid_len;
7941 
7942 	/*
7943 	 * At first sight, we don't know the size of the devid that the
7944 	 * server will return but this size will be encoded into the
7945 	 * reply. So we do a first request using a default size then we
7946 	 * check if this size was large enough. If not then we do a second
7947 	 * request with the correct size returned by the server. Note that
7948 	 * ldc requires size to be 8-byte aligned.
7949 	 */
7950 	bufsize = P2ROUNDUP(VD_DEVID_SIZE(VD_DEVID_DEFAULT_LEN),
7951 	    sizeof (uint64_t));
7952 	vd_devid = kmem_zalloc(bufsize, KM_SLEEP);
7953 	bufid_len = bufsize - sizeof (vd_efi_t) - 1;
7954 
7955 	rv = vdc_do_sync_op(vdc, VD_OP_GET_DEVID, (caddr_t)vd_devid,
7956 	    bufsize, 0, 0, CB_SYNC, 0, VIO_both_dir, B_TRUE);
7957 
7958 	DMSG(vdc, 2, "sync_op returned %d\n", rv);
7959 
7960 	if (rv) {
7961 		kmem_free(vd_devid, bufsize);
7962 		return (rv);
7963 	}
7964 
7965 	if (vd_devid->length > bufid_len) {
7966 		/*
7967 		 * The returned devid is larger than the buffer used. Try again
7968 		 * with a buffer with the right size.
7969 		 */
7970 		kmem_free(vd_devid, bufsize);
7971 		bufsize = P2ROUNDUP(VD_DEVID_SIZE(vd_devid->length),
7972 		    sizeof (uint64_t));
7973 		vd_devid = kmem_zalloc(bufsize, KM_SLEEP);
7974 		bufid_len = bufsize - sizeof (vd_efi_t) - 1;
7975 
7976 		rv = vdc_do_sync_op(vdc, VD_OP_GET_DEVID,
7977 		    (caddr_t)vd_devid, bufsize, 0, 0, CB_SYNC, 0,
7978 		    VIO_both_dir, B_TRUE);
7979 
7980 		if (rv) {
7981 			kmem_free(vd_devid, bufsize);
7982 			return (rv);
7983 		}
7984 	}
7985 
7986 	/*
7987 	 * The virtual disk should have the same device id as the one associated
7988 	 * with the physical disk it is mapped on, otherwise sharing a disk
7989 	 * between a LDom and a non-LDom may not work (for example for a shared
7990 	 * SVM disk set).
7991 	 *
7992 	 * The DDI framework does not allow creating a device id with any
7993 	 * type so we first create a device id of type DEVID_ENCAP and then
7994 	 * we restore the orignal type of the physical device.
7995 	 */
7996 
7997 	DMSG(vdc, 2, ": devid length = %d\n", vd_devid->length);
7998 
7999 	/* build an encapsulated devid based on the returned devid */
8000 	if (ddi_devid_init(vdc->dip, DEVID_ENCAP, vd_devid->length,
8001 	    vd_devid->id, &vdc->devid) != DDI_SUCCESS) {
8002 		DMSG(vdc, 1, "[%d] Fail to created devid\n", vdc->instance);
8003 		kmem_free(vd_devid, bufsize);
8004 		return (1);
8005 	}
8006 
8007 	DEVID_FORMTYPE((impl_devid_t *)vdc->devid, vd_devid->type);
8008 
8009 	ASSERT(ddi_devid_valid(vdc->devid) == DDI_SUCCESS);
8010 
8011 	kmem_free(vd_devid, bufsize);
8012 
8013 	if (ddi_devid_register(vdc->dip, vdc->devid) != DDI_SUCCESS) {
8014 		DMSG(vdc, 1, "[%d] Fail to register devid\n", vdc->instance);
8015 		return (1);
8016 	}
8017 
8018 	return (0);
8019 }
8020 
8021 static void
8022 vdc_store_label_efi(vdc_t *vdc, efi_gpt_t *gpt, efi_gpe_t *gpe)
8023 {
8024 	int i, nparts;
8025 
8026 	ASSERT(MUTEX_HELD(&vdc->lock));
8027 
8028 	vdc->vdisk_label = VD_DISK_LABEL_EFI;
8029 	bzero(vdc->vtoc, sizeof (struct extvtoc));
8030 	bzero(vdc->geom, sizeof (struct dk_geom));
8031 	bzero(vdc->slice, sizeof (vd_slice_t) * V_NUMPAR);
8032 
8033 	nparts = gpt->efi_gpt_NumberOfPartitionEntries;
8034 
8035 	for (i = 0; i < nparts && i < VD_EFI_WD_SLICE; i++) {
8036 
8037 		if (gpe[i].efi_gpe_StartingLBA == 0 ||
8038 		    gpe[i].efi_gpe_EndingLBA == 0) {
8039 			continue;
8040 		}
8041 
8042 		vdc->slice[i].start = gpe[i].efi_gpe_StartingLBA;
8043 		vdc->slice[i].nblocks = gpe[i].efi_gpe_EndingLBA -
8044 		    gpe[i].efi_gpe_StartingLBA + 1;
8045 	}
8046 
8047 	ASSERT(vdc->vdisk_size != 0);
8048 	vdc->slice[VD_EFI_WD_SLICE].start = 0;
8049 	vdc->slice[VD_EFI_WD_SLICE].nblocks = vdc->vdisk_size;
8050 
8051 }
8052 
8053 static void
8054 vdc_store_label_vtoc(vdc_t *vdc, struct dk_geom *geom, struct extvtoc *vtoc)
8055 {
8056 	int i;
8057 
8058 	ASSERT(MUTEX_HELD(&vdc->lock));
8059 	ASSERT(vdc->block_size == vtoc->v_sectorsz);
8060 
8061 	vdc->vdisk_label = VD_DISK_LABEL_VTOC;
8062 	bcopy(vtoc, vdc->vtoc, sizeof (struct extvtoc));
8063 	bcopy(geom, vdc->geom, sizeof (struct dk_geom));
8064 	bzero(vdc->slice, sizeof (vd_slice_t) * V_NUMPAR);
8065 
8066 	for (i = 0; i < vtoc->v_nparts; i++) {
8067 		vdc->slice[i].start = vtoc->v_part[i].p_start;
8068 		vdc->slice[i].nblocks = vtoc->v_part[i].p_size;
8069 	}
8070 }
8071 
8072 static void
8073 vdc_store_label_unk(vdc_t *vdc)
8074 {
8075 	ASSERT(MUTEX_HELD(&vdc->lock));
8076 
8077 	vdc->vdisk_label = VD_DISK_LABEL_UNK;
8078 	bzero(vdc->vtoc, sizeof (struct extvtoc));
8079 	bzero(vdc->geom, sizeof (struct dk_geom));
8080 	bzero(vdc->slice, sizeof (vd_slice_t) * V_NUMPAR);
8081 }
8082