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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/cpuvar.h>
27 #include <sys/types.h>
28 #include <sys/conf.h>
29 #include <sys/stat.h>
30 #include <sys/file.h>
31 #include <sys/ddi.h>
32 #include <sys/sunddi.h>
33 #include <sys/modctl.h>
34 #include <sys/sysmacros.h>
35 #include <sys/socket.h>
36 #include <sys/strsubr.h>
37 #include <sys/nvpair.h>
38 
39 #include <sys/stmf.h>
40 #include <sys/stmf_ioctl.h>
41 #include <sys/portif.h>
42 #include <sys/idm/idm.h>
43 #include <sys/idm/idm_conn_sm.h>
44 #include <iscsit_isns.h>
45 #include <iscsit.h>
46 
47 #define	ISCSIT_VERSION		BUILD_DATE "-1.18dev"
48 #define	ISCSIT_NAME_VERSION	"COMSTAR ISCSIT v" ISCSIT_VERSION
49 
50 /*
51  * DDI entry points.
52  */
53 static int iscsit_drv_attach(dev_info_t *, ddi_attach_cmd_t);
54 static int iscsit_drv_detach(dev_info_t *, ddi_detach_cmd_t);
55 static int iscsit_drv_getinfo(dev_info_t *, ddi_info_cmd_t, void *, void **);
56 static int iscsit_drv_open(dev_t *, int, int, cred_t *);
57 static int iscsit_drv_close(dev_t, int, int, cred_t *);
58 static boolean_t iscsit_drv_busy(void);
59 static int iscsit_drv_ioctl(dev_t, int, intptr_t, int, cred_t *, int *);
60 
61 extern struct mod_ops mod_miscops;
62 
63 
64 static struct cb_ops iscsit_cb_ops = {
65 	iscsit_drv_open,	/* cb_open */
66 	iscsit_drv_close,	/* cb_close */
67 	nodev,			/* cb_strategy */
68 	nodev,			/* cb_print */
69 	nodev,			/* cb_dump */
70 	nodev,			/* cb_read */
71 	nodev,			/* cb_write */
72 	iscsit_drv_ioctl,	/* cb_ioctl */
73 	nodev,			/* cb_devmap */
74 	nodev,			/* cb_mmap */
75 	nodev,			/* cb_segmap */
76 	nochpoll,		/* cb_chpoll */
77 	ddi_prop_op,		/* cb_prop_op */
78 	NULL,			/* cb_streamtab */
79 	D_MP,			/* cb_flag */
80 	CB_REV,			/* cb_rev */
81 	nodev,			/* cb_aread */
82 	nodev,			/* cb_awrite */
83 };
84 
85 static struct dev_ops iscsit_dev_ops = {
86 	DEVO_REV,		/* devo_rev */
87 	0,			/* devo_refcnt */
88 	iscsit_drv_getinfo,	/* devo_getinfo */
89 	nulldev,		/* devo_identify */
90 	nulldev,		/* devo_probe */
91 	iscsit_drv_attach,	/* devo_attach */
92 	iscsit_drv_detach,	/* devo_detach */
93 	nodev,			/* devo_reset */
94 	&iscsit_cb_ops,		/* devo_cb_ops */
95 	NULL,			/* devo_bus_ops */
96 	NULL,			/* devo_power */
97 	ddi_quiesce_not_needed,	/* quiesce */
98 };
99 
100 static struct modldrv modldrv = {
101 	&mod_driverops,
102 	"iSCSI Target",
103 	&iscsit_dev_ops,
104 };
105 
106 static struct modlinkage modlinkage = {
107 	MODREV_1,
108 	&modldrv,
109 	NULL,
110 };
111 
112 
113 iscsit_global_t iscsit_global;
114 
115 kmem_cache_t	*iscsit_status_pdu_cache;
116 
117 boolean_t	iscsit_sm_logging = B_FALSE;
118 
119 static idm_status_t iscsit_init(dev_info_t *dip);
120 static idm_status_t iscsit_enable_svc(iscsit_hostinfo_t *hostinfo);
121 static void iscsit_disable_svc(void);
122 
123 static void
124 iscsit_op_scsi_task_mgmt(iscsit_conn_t *ict, idm_pdu_t *rx_pdu);
125 
126 static void
127 iscsit_pdu_op_noop(iscsit_conn_t *ict, idm_pdu_t *rx_pdu);
128 
129 static void
130 iscsit_pdu_op_login_cmd(iscsit_conn_t *ict, idm_pdu_t *rx_pdu);
131 
132 void
133 iscsit_pdu_op_text_cmd(iscsit_conn_t *ict, idm_pdu_t *rx_pdu);
134 
135 static void
136 iscsit_pdu_op_logout_cmd(iscsit_conn_t *ict, idm_pdu_t *rx_pdu);
137 
138 int iscsit_cmd_window();
139 
140 void
141 iscsit_set_cmdsn(iscsit_conn_t *ict, idm_pdu_t *rx_pdu);
142 
143 static void
144 iscsit_calc_rspsn(iscsit_conn_t *ict, idm_pdu_t *resp);
145 
146 static void
147 iscsit_deferred_dispatch(idm_pdu_t *rx_pdu);
148 
149 static void
150 iscsit_deferred(void *rx_pdu_void);
151 
152 static idm_status_t
153 iscsit_conn_accept(idm_conn_t *ic);
154 
155 static idm_status_t
156 iscsit_ffp_enabled(idm_conn_t *ic);
157 
158 static idm_status_t
159 iscsit_ffp_disabled(idm_conn_t *ic, idm_ffp_disable_t disable_class);
160 
161 static idm_status_t
162 iscsit_conn_lost(idm_conn_t *ic);
163 
164 static idm_status_t
165 iscsit_conn_destroy(idm_conn_t *ic);
166 
167 static stmf_data_buf_t *
168 iscsit_dbuf_alloc(scsi_task_t *task, uint32_t size, uint32_t *pminsize,
169     uint32_t flags);
170 
171 static void
172 iscsit_dbuf_free(stmf_dbuf_store_t *ds, stmf_data_buf_t *dbuf);
173 
174 static void
175 iscsit_buf_xfer_cb(idm_buf_t *idb, idm_status_t status);
176 
177 static void
178 iscsit_send_good_status_done(idm_pdu_t *pdu, idm_status_t status);
179 
180 static void
181 iscsit_send_status_done(idm_pdu_t *pdu, idm_status_t status);
182 
183 static stmf_status_t
184 iscsit_idm_to_stmf(idm_status_t idmrc);
185 
186 static iscsit_task_t *
187 iscsit_task_alloc(iscsit_conn_t *ict);
188 
189 static void
190 iscsit_task_free(iscsit_task_t *itask);
191 
192 static iscsit_task_t *
193 iscsit_tm_task_alloc(iscsit_conn_t *ict);
194 
195 static void
196 iscsit_tm_task_free(iscsit_task_t *itask);
197 
198 static idm_status_t
199 iscsit_task_start(iscsit_task_t *itask);
200 
201 static void
202 iscsit_task_done(iscsit_task_t *itask);
203 
204 static int
205 iscsit_status_pdu_constructor(void *pdu_void, void *arg, int flags);
206 
207 static void
208 iscsit_pp_cb(struct stmf_port_provider *pp, int cmd, void *arg, uint32_t flags);
209 
210 static it_cfg_status_t
211 iscsit_config_merge(it_config_t *cfg);
212 
213 static idm_status_t
214 iscsit_login_fail(idm_conn_t *ic);
215 
216 static boolean_t iscsit_cmdsn_in_window(iscsit_conn_t *ict, uint32_t cmdsn);
217 static void iscsit_send_direct_scsi_resp(iscsit_conn_t *ict, idm_pdu_t *rx_pdu,
218     uint8_t response, uint8_t cmd_status);
219 static void iscsit_send_task_mgmt_resp(idm_pdu_t *tm_resp_pdu,
220     uint8_t tm_status);
221 
222 int
223 _init(void)
224 {
225 	int rc;
226 
227 	rw_init(&iscsit_global.global_rwlock, NULL, RW_DRIVER, NULL);
228 	iscsit_global.global_svc_state = ISE_DETACHED;
229 
230 	if ((rc = mod_install(&modlinkage)) != 0) {
231 		rw_destroy(&iscsit_global.global_rwlock);
232 		return (rc);
233 	}
234 
235 	return (rc);
236 }
237 
238 int
239 _info(struct modinfo *modinfop)
240 {
241 	return (mod_info(&modlinkage, modinfop));
242 }
243 
244 int
245 _fini(void)
246 {
247 	int rc;
248 
249 	rc = mod_remove(&modlinkage);
250 
251 	if (rc == 0) {
252 		rw_destroy(&iscsit_global.global_rwlock);
253 	}
254 
255 	return (rc);
256 }
257 
258 /*
259  * DDI entry points.
260  */
261 
262 /* ARGSUSED */
263 static int
264 iscsit_drv_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg,
265     void **result)
266 {
267 	ulong_t instance = getminor((dev_t)arg);
268 
269 	switch (cmd) {
270 	case DDI_INFO_DEVT2DEVINFO:
271 		*result = iscsit_global.global_dip;
272 		return (DDI_SUCCESS);
273 
274 	case DDI_INFO_DEVT2INSTANCE:
275 		*result = (void *)instance;
276 		return (DDI_SUCCESS);
277 
278 	default:
279 		break;
280 	}
281 
282 	return (DDI_FAILURE);
283 }
284 
285 static int
286 iscsit_drv_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
287 {
288 	if (cmd != DDI_ATTACH) {
289 		return (DDI_FAILURE);
290 	}
291 
292 	if (ddi_get_instance(dip) != 0) {
293 		/* we only allow instance 0 to attach */
294 		return (DDI_FAILURE);
295 	}
296 
297 	/* create the minor node */
298 	if (ddi_create_minor_node(dip, ISCSIT_MODNAME, S_IFCHR, 0,
299 	    DDI_PSEUDO, 0) != DDI_SUCCESS) {
300 		cmn_err(CE_WARN, "iscsit_drv_attach: "
301 		    "failed creating minor node");
302 		return (DDI_FAILURE);
303 	}
304 
305 	if (iscsit_init(dip) != IDM_STATUS_SUCCESS) {
306 		cmn_err(CE_WARN, "iscsit_drv_attach: "
307 		    "failed to initialize");
308 		ddi_remove_minor_node(dip, NULL);
309 		return (DDI_FAILURE);
310 	}
311 
312 	iscsit_global.global_svc_state = ISE_DISABLED;
313 	iscsit_global.global_dip = dip;
314 
315 	return (DDI_SUCCESS);
316 }
317 
318 /*ARGSUSED*/
319 static int
320 iscsit_drv_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
321 {
322 	if (cmd != DDI_DETACH)
323 		return (DDI_FAILURE);
324 
325 	ISCSIT_GLOBAL_LOCK(RW_WRITER);
326 	if (iscsit_drv_busy()) {
327 		ISCSIT_GLOBAL_UNLOCK();
328 		return (EBUSY);
329 	}
330 
331 	iscsit_global.global_dip = NULL;
332 	ddi_remove_minor_node(dip, NULL);
333 
334 	ldi_ident_release(iscsit_global.global_li);
335 	iscsit_global.global_svc_state = ISE_DETACHED;
336 
337 	ISCSIT_GLOBAL_UNLOCK();
338 
339 	return (DDI_SUCCESS);
340 }
341 
342 /*ARGSUSED*/
343 static int
344 iscsit_drv_open(dev_t *devp, int flag, int otyp, cred_t *credp)
345 {
346 	return (0);
347 }
348 
349 /* ARGSUSED */
350 static int
351 iscsit_drv_close(dev_t dev, int flag, int otyp, cred_t *credp)
352 {
353 	return (0);
354 }
355 
356 static boolean_t
357 iscsit_drv_busy(void)
358 {
359 	switch (iscsit_global.global_svc_state) {
360 	case ISE_DISABLED:
361 	case ISE_DETACHED:
362 		return (B_FALSE);
363 	default:
364 		return (B_TRUE);
365 	}
366 	/* NOTREACHED */
367 }
368 
369 /* ARGSUSED */
370 static int
371 iscsit_drv_ioctl(dev_t drv, int cmd, intptr_t argp, int flag, cred_t *cred,
372     int *retval)
373 {
374 	iscsit_ioc_set_config_t		setcfg;
375 	iscsit_ioc_set_config32_t	setcfg32;
376 	/* iscsit_ioc_get_config_t	getcfg; */
377 	char				*cfg_pnvlist;
378 	nvlist_t			*cfg_nvlist;
379 	it_config_t			*cfg;
380 	idm_status_t			idmrc;
381 	int				rc = 0;
382 
383 	if (drv_priv(cred) != 0) {
384 		return (EPERM);
385 	}
386 
387 	ISCSIT_GLOBAL_LOCK(RW_WRITER);
388 
389 	/*
390 	 * Validate ioctl requests against global service state
391 	 */
392 	switch (iscsit_global.global_svc_state) {
393 	case ISE_ENABLED:
394 		if (cmd == ISCSIT_IOC_DISABLE_SVC) {
395 			iscsit_global.global_svc_state = ISE_DISABLING;
396 		} else if (cmd == ISCSIT_IOC_ENABLE_SVC) {
397 			/* Already enabled */
398 			ISCSIT_GLOBAL_UNLOCK();
399 			return (0);
400 		} else {
401 			iscsit_global.global_svc_state = ISE_BUSY;
402 		}
403 		break;
404 	case ISE_DISABLED:
405 		if (cmd == ISCSIT_IOC_ENABLE_SVC) {
406 			iscsit_global.global_svc_state = ISE_ENABLING;
407 		} else if (cmd == ISCSIT_IOC_DISABLE_SVC) {
408 			/* Already disabled */
409 			ISCSIT_GLOBAL_UNLOCK();
410 			return (0);
411 		} else {
412 			rc = EFAULT;
413 		}
414 		break;
415 	case ISE_ENABLING:
416 	case ISE_DISABLING:
417 		rc = EAGAIN;
418 		break;
419 	case ISE_DETACHED:
420 	default:
421 		rc = EFAULT;
422 		break;
423 	}
424 
425 	ISCSIT_GLOBAL_UNLOCK();
426 	if (rc != 0)
427 		return (rc);
428 
429 	/* Handle ioctl request (enable/disable have already been handled) */
430 	switch (cmd) {
431 	case ISCSIT_IOC_SET_CONFIG:
432 		switch (ddi_model_convert_from(flag & FMODELS)) {
433 		case DDI_MODEL_ILP32:
434 			if (ddi_copyin((void *)argp, &setcfg32,
435 			    sizeof (iscsit_ioc_set_config32_t), flag) != 0)
436 				return (EFAULT);
437 
438 			setcfg.set_cfg_pnvlist =
439 			    (char *)((uintptr_t)setcfg32.set_cfg_pnvlist);
440 			setcfg.set_cfg_vers = setcfg32.set_cfg_vers;
441 			setcfg.set_cfg_pnvlist_len =
442 			    setcfg32.set_cfg_pnvlist_len;
443 			break;
444 		case DDI_MODEL_NONE:
445 			if (ddi_copyin((void *)argp, &setcfg,
446 			    sizeof (iscsit_ioc_set_config_t), flag) != 0)
447 				return (EFAULT);
448 			break;
449 		}
450 
451 		/* Check API version */
452 		if (setcfg.set_cfg_vers != ISCSIT_API_VERS0) {
453 			return (EINVAL);
454 		}
455 
456 		/* Config is in packed nvlist format so unpack it */
457 		cfg_pnvlist = kmem_alloc(setcfg.set_cfg_pnvlist_len,
458 		    KM_SLEEP);
459 		ASSERT(cfg_pnvlist != NULL);
460 
461 		if (ddi_copyin(setcfg.set_cfg_pnvlist, cfg_pnvlist,
462 		    setcfg.set_cfg_pnvlist_len, flag) != 0) {
463 			kmem_free(cfg_pnvlist, setcfg.set_cfg_pnvlist_len);
464 			return (EFAULT);
465 		}
466 
467 		if (nvlist_unpack(cfg_pnvlist, setcfg.set_cfg_pnvlist_len,
468 		    &cfg_nvlist, KM_SLEEP) != 0) {
469 			kmem_free(cfg_pnvlist, setcfg.set_cfg_pnvlist_len);
470 			return (EINVAL);
471 		}
472 
473 		/* Translate nvlist */
474 		if (it_nv_to_config(cfg_nvlist, &cfg) != 0) {
475 			cmn_err(CE_WARN, "Configuration is invalid");
476 			kmem_free(cfg_pnvlist, setcfg.set_cfg_pnvlist_len);
477 			nvlist_free(cfg_nvlist);
478 			return (EINVAL);
479 		}
480 
481 		/* Update config */
482 		if (iscsit_config_merge(cfg) != 0) {
483 			kmem_free(cfg_pnvlist, setcfg.set_cfg_pnvlist_len);
484 			nvlist_free(cfg_nvlist);
485 			return (EIO);
486 		}
487 
488 		it_config_free_cmn(cfg);
489 		kmem_free(cfg_pnvlist, setcfg.set_cfg_pnvlist_len);
490 		nvlist_free(cfg_nvlist);
491 
492 		/*
493 		 * Now that the reconfig is complete set our state back to
494 		 * enabled.
495 		 */
496 		ISCSIT_GLOBAL_LOCK(RW_WRITER);
497 		iscsit_global.global_svc_state = ISE_ENABLED;
498 		ISCSIT_GLOBAL_UNLOCK();
499 		break;
500 	case ISCSIT_IOC_ENABLE_SVC: {
501 		iscsit_hostinfo_t hostinfo;
502 
503 		if (ddi_copyin((void *)argp, &hostinfo.length,
504 		    sizeof (hostinfo.length), flag) != 0) {
505 			iscsit_global.global_svc_state = ISE_DISABLED;
506 			return (EFAULT);
507 		}
508 
509 		if (hostinfo.length > sizeof (hostinfo.fqhn))
510 			hostinfo.length = sizeof (hostinfo.fqhn);
511 
512 		if (ddi_copyin((void *)((caddr_t)argp +
513 		    sizeof (hostinfo.length)), &hostinfo.fqhn,
514 		    hostinfo.length, flag) != 0) {
515 			iscsit_global.global_svc_state = ISE_DISABLED;
516 			return (EFAULT);
517 		}
518 
519 		idmrc = iscsit_enable_svc(&hostinfo);
520 		ISCSIT_GLOBAL_LOCK(RW_WRITER);
521 		if (idmrc == IDM_STATUS_SUCCESS) {
522 			iscsit_global.global_svc_state = ISE_ENABLED;
523 		} else {
524 			rc = EIO;
525 			iscsit_global.global_svc_state = ISE_DISABLED;
526 		}
527 		ISCSIT_GLOBAL_UNLOCK();
528 		break;
529 	}
530 	case ISCSIT_IOC_DISABLE_SVC:
531 		iscsit_disable_svc();
532 		ISCSIT_GLOBAL_LOCK(RW_WRITER);
533 		iscsit_global.global_svc_state = ISE_DISABLED;
534 		ISCSIT_GLOBAL_UNLOCK();
535 		break;
536 	default:
537 		rc = EINVAL;
538 	}
539 
540 	/* Don't forget to clear ISE_BUSY state */
541 	ASSERT(iscsit_global.global_svc_state != ISE_BUSY);
542 
543 	return (rc);
544 }
545 
546 static idm_status_t
547 iscsit_init(dev_info_t *dip)
548 {
549 	int			rc;
550 
551 	rc = ldi_ident_from_dip(dip, &iscsit_global.global_li);
552 	ASSERT(rc == 0);  /* Failure indicates invalid argument */
553 
554 	iscsit_global.global_svc_state = ISE_DISABLED;
555 
556 	return (IDM_STATUS_SUCCESS);
557 }
558 
559 /*
560  * iscsit_enable_svc
561  *
562  * registers all the configured targets and target portals with STMF
563  */
564 static idm_status_t
565 iscsit_enable_svc(iscsit_hostinfo_t *hostinfo)
566 {
567 	stmf_port_provider_t	*pp;
568 	stmf_dbuf_store_t	*dbuf_store;
569 	boolean_t		did_iscsit_isns_init;
570 	idm_status_t		retval = IDM_STATUS_SUCCESS;
571 
572 	ASSERT(iscsit_global.global_svc_state == ISE_ENABLING);
573 
574 	/*
575 	 * Make sure that can tell if we have partially allocated
576 	 * in case we need to exit and tear down anything allocated.
577 	 */
578 	iscsit_global.global_tsih_pool = NULL;
579 	iscsit_global.global_dbuf_store = NULL;
580 	iscsit_status_pdu_cache = NULL;
581 	pp = NULL;
582 	iscsit_global.global_pp = NULL;
583 	iscsit_global.global_default_tpg = NULL;
584 	did_iscsit_isns_init = B_FALSE;
585 	iscsit_global.global_dispatch_taskq = NULL;
586 
587 	/* Setup remaining fields in iscsit_global_t */
588 	idm_refcnt_init(&iscsit_global.global_refcnt,
589 	    &iscsit_global);
590 
591 	avl_create(&iscsit_global.global_discovery_sessions,
592 	    iscsit_sess_avl_compare, sizeof (iscsit_sess_t),
593 	    offsetof(iscsit_sess_t, ist_tgt_ln));
594 
595 	avl_create(&iscsit_global.global_target_list,
596 	    iscsit_tgt_avl_compare, sizeof (iscsit_tgt_t),
597 	    offsetof(iscsit_tgt_t, target_global_ln));
598 
599 	list_create(&iscsit_global.global_deleted_target_list,
600 	    sizeof (iscsit_tgt_t),
601 	    offsetof(iscsit_tgt_t, target_global_deleted_ln));
602 
603 	avl_create(&iscsit_global.global_tpg_list,
604 	    iscsit_tpg_avl_compare, sizeof (iscsit_tpg_t),
605 	    offsetof(iscsit_tpg_t, tpg_global_ln));
606 
607 	avl_create(&iscsit_global.global_ini_list,
608 	    iscsit_ini_avl_compare, sizeof (iscsit_ini_t),
609 	    offsetof(iscsit_ini_t, ini_global_ln));
610 
611 	iscsit_global.global_tsih_pool = vmem_create("iscsit_tsih_pool",
612 	    (void *)1, ISCSI_MAX_TSIH, 1, NULL, NULL, NULL, 0,
613 	    VM_SLEEP | VMC_IDENTIFIER);
614 
615 	/*
616 	 * Setup STMF dbuf store.  Our buffers are bound to a specific
617 	 * connection so we really can't let STMF cache buffers for us.
618 	 * Consequently we'll just allocate one global buffer store.
619 	 */
620 	dbuf_store = stmf_alloc(STMF_STRUCT_DBUF_STORE, 0, 0);
621 	if (dbuf_store == NULL) {
622 		retval = IDM_STATUS_FAIL;
623 		goto tear_down_and_return;
624 	}
625 	dbuf_store->ds_alloc_data_buf = iscsit_dbuf_alloc;
626 	dbuf_store->ds_free_data_buf = iscsit_dbuf_free;
627 	dbuf_store->ds_port_private = NULL;
628 	iscsit_global.global_dbuf_store = dbuf_store;
629 
630 	/* Status PDU cache */
631 	iscsit_status_pdu_cache = kmem_cache_create("iscsit_status_pdu_cache",
632 	    sizeof (idm_pdu_t) + sizeof (iscsi_scsi_rsp_hdr_t), 8,
633 	    &iscsit_status_pdu_constructor,
634 	    NULL, NULL, NULL, NULL, KM_SLEEP);
635 
636 	/* Default TPG and portal */
637 	iscsit_global.global_default_tpg = iscsit_tpg_createdefault();
638 	if (iscsit_global.global_default_tpg == NULL) {
639 		retval = IDM_STATUS_FAIL;
640 		goto tear_down_and_return;
641 	}
642 
643 	/* initialize isns client */
644 	(void) iscsit_isns_init(hostinfo);
645 	did_iscsit_isns_init = B_TRUE;
646 
647 	/* Register port provider */
648 	pp = stmf_alloc(STMF_STRUCT_PORT_PROVIDER, 0, 0);
649 	if (pp == NULL) {
650 		retval = IDM_STATUS_FAIL;
651 		goto tear_down_and_return;
652 	}
653 
654 	pp->pp_portif_rev = PORTIF_REV_1;
655 	pp->pp_instance = 0;
656 	pp->pp_name = ISCSIT_MODNAME;
657 	pp->pp_cb = iscsit_pp_cb;
658 
659 	iscsit_global.global_pp = pp;
660 
661 
662 	if (stmf_register_port_provider(pp) != STMF_SUCCESS) {
663 		retval = IDM_STATUS_FAIL;
664 		goto tear_down_and_return;
665 	}
666 
667 	iscsit_global.global_dispatch_taskq = taskq_create("iscsit_dispatch",
668 	    1, minclsyspri, 16, 16, TASKQ_PREPOPULATE);
669 
670 	return (IDM_STATUS_SUCCESS);
671 
672 tear_down_and_return:
673 
674 	if (iscsit_global.global_dispatch_taskq) {
675 		taskq_destroy(iscsit_global.global_dispatch_taskq);
676 		iscsit_global.global_dispatch_taskq = NULL;
677 	}
678 
679 	if (did_iscsit_isns_init)
680 		iscsit_isns_fini();
681 
682 	if (iscsit_global.global_default_tpg) {
683 		iscsit_tpg_destroydefault(iscsit_global.global_default_tpg);
684 		iscsit_global.global_default_tpg = NULL;
685 	}
686 
687 	if (iscsit_global.global_pp)
688 		iscsit_global.global_pp = NULL;
689 
690 	if (pp)
691 		stmf_free(pp);
692 
693 	if (iscsit_status_pdu_cache) {
694 		kmem_cache_destroy(iscsit_status_pdu_cache);
695 		iscsit_status_pdu_cache = NULL;
696 	}
697 
698 	if (iscsit_global.global_dbuf_store) {
699 		stmf_free(iscsit_global.global_dbuf_store);
700 		iscsit_global.global_dbuf_store = NULL;
701 	}
702 
703 	if (iscsit_global.global_tsih_pool) {
704 		vmem_destroy(iscsit_global.global_tsih_pool);
705 		iscsit_global.global_tsih_pool = NULL;
706 	}
707 
708 	avl_destroy(&iscsit_global.global_ini_list);
709 	avl_destroy(&iscsit_global.global_tpg_list);
710 	list_destroy(&iscsit_global.global_deleted_target_list);
711 	avl_destroy(&iscsit_global.global_target_list);
712 	avl_destroy(&iscsit_global.global_discovery_sessions);
713 
714 	idm_refcnt_destroy(&iscsit_global.global_refcnt);
715 
716 	return (retval);
717 }
718 
719 /*
720  * iscsit_disable_svc
721  *
722  * clean up all existing connections and deregister targets from STMF
723  */
724 static void
725 iscsit_disable_svc(void)
726 {
727 	iscsit_sess_t	*sess;
728 
729 	ASSERT(iscsit_global.global_svc_state == ISE_DISABLING);
730 
731 	/* tear down discovery sessions */
732 	for (sess = avl_first(&iscsit_global.global_discovery_sessions);
733 	    sess != NULL;
734 	    sess = AVL_NEXT(&iscsit_global.global_discovery_sessions, sess))
735 		iscsit_sess_close(sess);
736 
737 	/*
738 	 * Passing NULL to iscsit_config_merge tells it to go to an empty
739 	 * config.
740 	 */
741 	(void) iscsit_config_merge(NULL);
742 
743 	/*
744 	 * Wait until there are no more global references
745 	 */
746 	idm_refcnt_wait_ref(&iscsit_global.global_refcnt);
747 	idm_refcnt_destroy(&iscsit_global.global_refcnt);
748 
749 	/*
750 	 * Default TPG must be destroyed after global_refcnt is 0.
751 	 */
752 	iscsit_tpg_destroydefault(iscsit_global.global_default_tpg);
753 
754 	avl_destroy(&iscsit_global.global_discovery_sessions);
755 	list_destroy(&iscsit_global.global_deleted_target_list);
756 	avl_destroy(&iscsit_global.global_target_list);
757 	avl_destroy(&iscsit_global.global_tpg_list);
758 	avl_destroy(&iscsit_global.global_ini_list);
759 
760 	taskq_destroy(iscsit_global.global_dispatch_taskq);
761 
762 	iscsit_isns_fini();
763 
764 	stmf_free(iscsit_global.global_dbuf_store);
765 	iscsit_global.global_dbuf_store = NULL;
766 
767 	(void) stmf_deregister_port_provider(iscsit_global.global_pp);
768 	stmf_free(iscsit_global.global_pp);
769 	iscsit_global.global_pp = NULL;
770 
771 	kmem_cache_destroy(iscsit_status_pdu_cache);
772 	iscsit_status_pdu_cache = NULL;
773 
774 	vmem_destroy(iscsit_global.global_tsih_pool);
775 	iscsit_global.global_tsih_pool = NULL;
776 }
777 
778 void
779 iscsit_global_hold()
780 {
781 	idm_refcnt_hold(&iscsit_global.global_refcnt);
782 }
783 
784 void
785 iscsit_global_rele()
786 {
787 	idm_refcnt_rele(&iscsit_global.global_refcnt);
788 }
789 
790 void
791 iscsit_global_wait_ref()
792 {
793 	idm_refcnt_wait_ref(&iscsit_global.global_refcnt);
794 }
795 
796 /*
797  * IDM callbacks
798  */
799 
800 /*ARGSUSED*/
801 void
802 iscsit_rx_pdu(idm_conn_t *ic, idm_pdu_t *rx_pdu)
803 {
804 	iscsit_conn_t *ict = ic->ic_handle;
805 	switch (IDM_PDU_OPCODE(rx_pdu)) {
806 	case ISCSI_OP_SCSI_CMD:
807 		ASSERT(0); /* Shouldn't happen */
808 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
809 		break;
810 	case ISCSI_OP_SNACK_CMD:
811 		/*
812 		 * We'll need to handle this when we support ERL1/2.  For
813 		 * now we treat it as a protocol error.
814 		 */
815 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
816 		idm_conn_event(ic, CE_TRANSPORT_FAIL, NULL);
817 		break;
818 	case ISCSI_OP_SCSI_TASK_MGT_MSG:
819 		iscsit_set_cmdsn(ict, rx_pdu);
820 		iscsit_op_scsi_task_mgmt(ict, rx_pdu);
821 		break;
822 	case ISCSI_OP_NOOP_OUT:
823 	case ISCSI_OP_LOGIN_CMD:
824 	case ISCSI_OP_TEXT_CMD:
825 	case ISCSI_OP_LOGOUT_CMD:
826 		/*
827 		 * If/when we switch to userland processing these PDU's
828 		 * will be handled by iscsitd.
829 		 */
830 		iscsit_deferred_dispatch(rx_pdu);
831 		break;
832 	default:
833 		/* Protocol error */
834 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
835 		idm_conn_event(ic, CE_TRANSPORT_FAIL, NULL);
836 		break;
837 	}
838 }
839 
840 /*ARGSUSED*/
841 void
842 iscsit_rx_pdu_error(idm_conn_t *ic, idm_pdu_t *rx_pdu, idm_status_t status)
843 {
844 	idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
845 }
846 
847 void
848 iscsit_task_aborted(idm_task_t *idt, idm_status_t status)
849 {
850 	iscsit_task_t *itask = idt->idt_private;
851 
852 	switch (status) {
853 	case IDM_STATUS_SUSPENDED:
854 		break;
855 	case IDM_STATUS_ABORTED:
856 		mutex_enter(&itask->it_mutex);
857 		itask->it_aborted = B_TRUE;
858 		/*
859 		 * We rely on the fact that STMF tracks outstanding
860 		 * buffer transfers and will free all of our buffers
861 		 * before freeing the task so we don't need to
862 		 * explicitly free the buffers from iscsit/idm
863 		 */
864 		if (itask->it_stmf_abort) {
865 			mutex_exit(&itask->it_mutex);
866 			/*
867 			 * Task is no longer active
868 			 */
869 			iscsit_task_done(itask);
870 
871 			/*
872 			 * STMF has already asked for this task to be aborted
873 			 *
874 			 * STMF specification is wrong... says to return
875 			 * STMF_ABORTED, the code actually looks for
876 			 * STMF_ABORT_SUCCESS.
877 			 */
878 			stmf_task_lport_aborted(itask->it_stmf_task,
879 			    STMF_ABORT_SUCCESS, STMF_IOF_LPORT_DONE);
880 			return;
881 		} else {
882 			mutex_exit(&itask->it_mutex);
883 			/*
884 			 * Tell STMF to stop processing the task.
885 			 */
886 			stmf_abort(STMF_QUEUE_TASK_ABORT, itask->it_stmf_task,
887 			    STMF_ABORTED, NULL);
888 			return;
889 		}
890 		/*NOTREACHED*/
891 	default:
892 		ASSERT(0);
893 	}
894 }
895 
896 /*ARGSUSED*/
897 idm_status_t
898 iscsit_client_notify(idm_conn_t *ic, idm_client_notify_t icn,
899     uintptr_t data)
900 {
901 	idm_status_t rc = IDM_STATUS_SUCCESS;
902 
903 	/*
904 	 * IDM client notifications will never occur at interrupt level
905 	 * since they are generated from the connection state machine which
906 	 * running on taskq threads.
907 	 *
908 	 */
909 	switch (icn) {
910 	case CN_CONNECT_ACCEPT:
911 		rc = iscsit_conn_accept(ic); /* No data */
912 		break;
913 	case CN_FFP_ENABLED:
914 		rc = iscsit_ffp_enabled(ic); /* No data */
915 		break;
916 	case CN_FFP_DISABLED:
917 		/*
918 		 * Data indicates whether this was the result of an
919 		 * explicit logout request.
920 		 */
921 		rc = iscsit_ffp_disabled(ic, (idm_ffp_disable_t)data);
922 		break;
923 	case CN_CONNECT_LOST:
924 		rc = iscsit_conn_lost(ic);
925 		break;
926 	case CN_CONNECT_DESTROY:
927 		rc = iscsit_conn_destroy(ic);
928 		break;
929 	case CN_LOGIN_FAIL:
930 		/*
931 		 * Force the login state machine to completion
932 		 */
933 		rc = iscsit_login_fail(ic);
934 		break;
935 	default:
936 		rc = IDM_STATUS_REJECT;
937 		break;
938 	}
939 
940 	return (rc);
941 }
942 
943 
944 void
945 iscsit_build_hdr(idm_task_t *idm_task, idm_pdu_t *pdu, uint8_t opcode)
946 {
947 	iscsit_task_t *itask = idm_task->idt_private;
948 	iscsi_data_rsp_hdr_t *dh = (iscsi_data_rsp_hdr_t *)pdu->isp_hdr;
949 
950 	/*
951 	 * We acquired iscsit_sess_t.ist_sn_rwlock in iscsit_xfer_scsi_data
952 	 * in reader mode so we expect to be locked here
953 	 */
954 
955 	/*
956 	 * Lun is only required if the opcode == ISCSI_OP_SCSI_DATA_RSP
957 	 * and the 'A' bit is to be set
958 	 */
959 	dh->opcode = opcode;
960 	dh->itt = itask->it_itt;
961 	dh->ttt = itask->it_ttt;
962 	/* Maintain current statsn for RTT responses */
963 	dh->statsn = (opcode == ISCSI_OP_RTT_RSP) ?
964 	    htonl(itask->it_ict->ict_statsn) : 0;
965 	dh->expcmdsn = htonl(itask->it_ict->ict_sess->ist_expcmdsn);
966 	dh->maxcmdsn = htonl(itask->it_ict->ict_sess->ist_maxcmdsn);
967 
968 	/*
969 	 * IDM must set:
970 	 *
971 	 * data.flags and rtt.flags
972 	 * data.dlength
973 	 * data.datasn
974 	 * data.offset
975 	 * residual_count and cmd_status (if we ever implement phase collapse)
976 	 * rtt.rttsn
977 	 * rtt.data_offset
978 	 * rtt.data_length
979 	 */
980 }
981 
982 void
983 iscsit_keepalive(idm_conn_t *ic)
984 {
985 	idm_pdu_t		*nop_in_pdu;
986 	iscsi_nop_in_hdr_t	*nop_in;
987 	iscsit_conn_t		*ict = ic->ic_handle;
988 
989 	/*
990 	 * IDM noticed the connection has been idle for too long so it's
991 	 * time to provoke some activity.  Build and transmit an iSCSI
992 	 * nop-in PDU -- when the initiator responds it will be counted
993 	 * as "activity" and keep the connection alive.
994 	 *
995 	 * We don't actually care about the response here at the iscsit level
996 	 * so we will just throw it away without looking at it when it arrives.
997 	 */
998 	nop_in_pdu = idm_pdu_alloc(sizeof (*nop_in), 0);
999 	idm_pdu_init(nop_in_pdu, ic, NULL, NULL);
1000 
1001 	nop_in = (iscsi_nop_in_hdr_t *)nop_in_pdu->isp_hdr;
1002 	bzero(nop_in, sizeof (*nop_in));
1003 	nop_in->opcode = ISCSI_OP_NOOP_IN;
1004 	nop_in->flags = ISCSI_FLAG_FINAL;
1005 	nop_in->itt = ISCSI_RSVD_TASK_TAG;
1006 	/*
1007 	 * This works because we don't currently allocate ttt's anywhere else
1008 	 * in iscsit so as long as we stay out of IDM's range we are safe.
1009 	 * If we need to allocate ttt's for other PDU's in the future this will
1010 	 * need to be improved.
1011 	 */
1012 	mutex_enter(&ict->ict_mutex);
1013 	nop_in->ttt = ict->ict_keepalive_ttt;
1014 	ict->ict_keepalive_ttt++;
1015 	if (ict->ict_keepalive_ttt == ISCSI_RSVD_TASK_TAG)
1016 		ict->ict_keepalive_ttt = IDM_TASKIDS_MAX;
1017 	mutex_exit(&ict->ict_mutex);
1018 
1019 	iscsit_pdu_tx(nop_in_pdu);
1020 }
1021 
1022 static idm_status_t
1023 iscsit_conn_accept(idm_conn_t *ic)
1024 {
1025 	iscsit_conn_t *ict;
1026 
1027 	/*
1028 	 * We need to get a global hold here to ensure that the service
1029 	 * doesn't get shutdown prior to establishing a session. This
1030 	 * gets released in iscsit_conn_destroy().
1031 	 */
1032 	ISCSIT_GLOBAL_LOCK(RW_READER);
1033 	if (iscsit_global.global_svc_state != ISE_ENABLED) {
1034 		ISCSIT_GLOBAL_UNLOCK();
1035 		return (IDM_STATUS_FAIL);
1036 	}
1037 	iscsit_global_hold();
1038 	ISCSIT_GLOBAL_UNLOCK();
1039 
1040 	/*
1041 	 * Allocate an associated iscsit structure to represent this
1042 	 * connection.  We shouldn't really create a session until we
1043 	 * get the first login PDU.
1044 	 */
1045 	ict = kmem_zalloc(sizeof (*ict), KM_SLEEP);
1046 
1047 	ict->ict_ic = ic;
1048 	ict->ict_statsn = 1;
1049 	ict->ict_keepalive_ttt = IDM_TASKIDS_MAX; /* Avoid IDM TT range */
1050 	ic->ic_handle = ict;
1051 	mutex_init(&ict->ict_mutex, NULL, MUTEX_DRIVER, NULL);
1052 	idm_refcnt_init(&ict->ict_refcnt, ict);
1053 
1054 	/*
1055 	 * Initialize login state machine
1056 	 */
1057 	if (iscsit_login_sm_init(ict) != IDM_STATUS_SUCCESS) {
1058 		iscsit_global_rele();
1059 		/*
1060 		 * Cleanup the ict after idm notifies us about this failure
1061 		 */
1062 		return (IDM_STATUS_FAIL);
1063 	}
1064 
1065 	return (IDM_STATUS_SUCCESS);
1066 }
1067 
1068 idm_status_t
1069 iscsit_conn_reinstate(iscsit_conn_t *reinstate_ict, iscsit_conn_t *new_ict)
1070 {
1071 	idm_status_t	result;
1072 
1073 	/*
1074 	 * Note in new connection state that this connection is
1075 	 * reinstating an existing connection.
1076 	 */
1077 	new_ict->ict_reinstating = B_TRUE;
1078 	new_ict->ict_reinstate_conn = reinstate_ict;
1079 	new_ict->ict_statsn = reinstate_ict->ict_statsn;
1080 
1081 	/*
1082 	 * Now generate connection state machine event to existing connection
1083 	 * so that it starts the cleanup process.
1084 	 */
1085 	result = idm_conn_reinstate_event(reinstate_ict->ict_ic,
1086 	    new_ict->ict_ic);
1087 
1088 	return (result);
1089 }
1090 
1091 void
1092 iscsit_conn_hold(iscsit_conn_t *ict)
1093 {
1094 	idm_refcnt_hold(&ict->ict_refcnt);
1095 }
1096 
1097 void
1098 iscsit_conn_rele(iscsit_conn_t *ict)
1099 {
1100 	idm_refcnt_rele(&ict->ict_refcnt);
1101 }
1102 
1103 void
1104 iscsit_conn_dispatch_hold(iscsit_conn_t *ict)
1105 {
1106 	idm_refcnt_hold(&ict->ict_dispatch_refcnt);
1107 }
1108 
1109 void
1110 iscsit_conn_dispatch_rele(iscsit_conn_t *ict)
1111 {
1112 	idm_refcnt_rele(&ict->ict_dispatch_refcnt);
1113 }
1114 
1115 static idm_status_t
1116 iscsit_login_fail(idm_conn_t *ic)
1117 {
1118 	iscsit_conn_t *ict = ic->ic_handle;
1119 
1120 	/* Generate login state machine event */
1121 	iscsit_login_sm_event(ict, ILE_LOGIN_CONN_ERROR, NULL);
1122 
1123 	return (IDM_STATUS_SUCCESS);
1124 }
1125 
1126 static idm_status_t
1127 iscsit_ffp_enabled(idm_conn_t *ic)
1128 {
1129 	iscsit_conn_t *ict = ic->ic_handle;
1130 
1131 	/* Generate session state machine event */
1132 	iscsit_sess_sm_event(ict->ict_sess, SE_CONN_LOGGED_IN, ict);
1133 
1134 	return (IDM_STATUS_SUCCESS);
1135 }
1136 
1137 static idm_status_t
1138 iscsit_ffp_disabled(idm_conn_t *ic, idm_ffp_disable_t disable_class)
1139 {
1140 	iscsit_conn_t *ict = ic->ic_handle;
1141 
1142 	/* Generate session state machine event */
1143 	switch (disable_class) {
1144 	case FD_CONN_FAIL:
1145 		iscsit_sess_sm_event(ict->ict_sess, SE_CONN_FFP_FAIL, ict);
1146 		break;
1147 	case FD_CONN_LOGOUT:
1148 		iscsit_sess_sm_event(ict->ict_sess, SE_CONN_FFP_DISABLE, ict);
1149 		break;
1150 	case FD_SESS_LOGOUT:
1151 		iscsit_sess_sm_event(ict->ict_sess, SE_SESSION_CLOSE, ict);
1152 		break;
1153 	default:
1154 		ASSERT(0);
1155 	}
1156 
1157 	return (IDM_STATUS_SUCCESS);
1158 }
1159 
1160 static idm_status_t
1161 iscsit_conn_lost(idm_conn_t *ic)
1162 {
1163 	iscsit_conn_t *ict = ic->ic_handle;
1164 
1165 	mutex_enter(&ict->ict_mutex);
1166 	ict->ict_lost = B_TRUE;
1167 	mutex_exit(&ict->ict_mutex);
1168 
1169 	/*
1170 	 * Make sure there aren't any PDU's transitioning from the receive
1171 	 * handler to the dispatch taskq.
1172 	 */
1173 	idm_refcnt_wait_ref(&ict->ict_dispatch_refcnt);
1174 
1175 	return (IDM_STATUS_SUCCESS);
1176 }
1177 
1178 static idm_status_t
1179 iscsit_conn_destroy(idm_conn_t *ic)
1180 {
1181 	iscsit_conn_t *ict = ic->ic_handle;
1182 
1183 	mutex_enter(&ict->ict_mutex);
1184 	ict->ict_destroyed = B_TRUE;
1185 	mutex_exit(&ict->ict_mutex);
1186 
1187 	/* Generate session state machine event */
1188 	if (ict->ict_sess != NULL) {
1189 		/*
1190 		 * Session state machine will call iscsit_conn_destroy_done()
1191 		 * when it has removed references to this connection.
1192 		 */
1193 		iscsit_sess_sm_event(ict->ict_sess, SE_CONN_FAIL, ict);
1194 	}
1195 
1196 	ict->ict_ic = NULL;
1197 
1198 	idm_refcnt_wait_ref(&ict->ict_refcnt);
1199 
1200 	/* Reap the login state machine */
1201 	iscsit_login_sm_fini(ict);
1202 
1203 	/* Clean up any text command remnants */
1204 	iscsit_text_cmd_fini(ict);
1205 
1206 	mutex_destroy(&ict->ict_mutex);
1207 	idm_refcnt_destroy(&ict->ict_refcnt);
1208 	kmem_free(ict, sizeof (*ict));
1209 
1210 	iscsit_global_rele();
1211 
1212 	return (IDM_STATUS_SUCCESS);
1213 }
1214 
1215 /*
1216  * STMF-related functions
1217  *
1218  * iSCSI to STMF mapping
1219  *
1220  * Session == ?
1221  * Connection == bound to local port but not itself a local port
1222  * Target
1223  * Target portal (group?) == local port (really but we're not going to do this)
1224  *	iscsit needs to map connections to local ports (whatever we decide
1225  * 	they are)
1226  * Target == ?
1227  */
1228 
1229 /*ARGSUSED*/
1230 static stmf_data_buf_t *
1231 iscsit_dbuf_alloc(scsi_task_t *task, uint32_t size, uint32_t *pminsize,
1232     uint32_t flags)
1233 {
1234 	iscsit_task_t *itask = task->task_port_private;
1235 	idm_buf_t *idm_buffer;
1236 	iscsit_buf_t	*ibuf;
1237 	stmf_data_buf_t *result;
1238 	uint32_t	bsize;
1239 
1240 	/*
1241 	 * If iscsit is requested to allocate a buffer larger than
1242 	 * MaxBurstLength, then the allocation fails (dbuf = NULL)
1243 	 * and pminsize is modified to be equal to MaxBurstLength.
1244 	 * stmf/sbd then should re-invoke this function with the
1245 	 * corrected values for transfer. iscsit allocates a buffer
1246 	 * whose size is a minimum of the requested size and the
1247 	 * configured MaxBurstLength.
1248 	 */
1249 	ASSERT(pminsize);
1250 	bsize = min(size, *pminsize);
1251 	if (bsize > itask->it_ict->ict_op.op_max_burst_length) {
1252 		*pminsize = itask->it_ict->ict_op.op_max_burst_length;
1253 		return (NULL);
1254 	}
1255 
1256 	/* Alloc buffer */
1257 	idm_buffer = idm_buf_alloc(itask->it_ict->ict_ic, NULL, bsize);
1258 	if (idm_buffer != NULL) {
1259 		result = stmf_alloc(STMF_STRUCT_DATA_BUF,
1260 		    sizeof (iscsit_buf_t), 0);
1261 		if (result != NULL) {
1262 			/* Fill in stmf_data_buf_t */
1263 			ibuf = result->db_port_private;
1264 			ibuf->ibuf_idm_buf = idm_buffer;
1265 			ibuf->ibuf_stmf_buf = result;
1266 			ibuf->ibuf_is_immed = B_FALSE;
1267 			result->db_flags = DB_DONT_CACHE;
1268 			result->db_buf_size = bsize;
1269 			result->db_data_size = bsize;
1270 			result->db_sglist_length = 1;
1271 			result->db_sglist[0].seg_addr = idm_buffer->idb_buf;
1272 			result->db_sglist[0].seg_length =
1273 			    idm_buffer->idb_buflen;
1274 			return (result);
1275 		}
1276 
1277 		/* Couldn't get the stmf_data_buf_t so free the buffer */
1278 		idm_buf_free(idm_buffer);
1279 	}
1280 
1281 	return (NULL);
1282 }
1283 
1284 /*ARGSUSED*/
1285 static void
1286 iscsit_dbuf_free(stmf_dbuf_store_t *ds, stmf_data_buf_t *dbuf)
1287 {
1288 	iscsit_buf_t *ibuf = dbuf->db_port_private;
1289 
1290 	if (ibuf->ibuf_is_immed) {
1291 		/*
1292 		 * The iscsit_buf_t structure itself will be freed with its
1293 		 * associated task.  Here we just need to free the PDU that
1294 		 * held the immediate data.
1295 		 */
1296 		idm_pdu_complete(ibuf->ibuf_immed_data_pdu, IDM_STATUS_SUCCESS);
1297 		ibuf->ibuf_immed_data_pdu = 0;
1298 	} else {
1299 		idm_buf_free(ibuf->ibuf_idm_buf);
1300 		stmf_free(dbuf);
1301 	}
1302 }
1303 
1304 /*ARGSUSED*/
1305 stmf_status_t
1306 iscsit_xfer_scsi_data(scsi_task_t *task, stmf_data_buf_t *dbuf,
1307     uint32_t ioflags)
1308 {
1309 	iscsit_task_t *iscsit_task = task->task_port_private;
1310 	iscsit_buf_t *ibuf = dbuf->db_port_private;
1311 	int idm_rc;
1312 
1313 	/*
1314 	 * If we are aborting then we can ignore this request
1315 	 */
1316 	if (iscsit_task->it_stmf_abort) {
1317 		return (STMF_SUCCESS);
1318 	}
1319 
1320 	/*
1321 	 * If it's not immediate data then start the transfer
1322 	 */
1323 	ASSERT(ibuf->ibuf_is_immed == B_FALSE);
1324 	if (dbuf->db_flags & DB_DIRECTION_TO_RPORT) {
1325 		/*
1326 		 * IDM will call iscsit_build_hdr so lock now to serialize
1327 		 * access to the SN values.  We need to lock here to enforce
1328 		 * lock ordering
1329 		 */
1330 		rw_enter(&iscsit_task->it_ict->ict_sess->ist_sn_rwlock,
1331 		    RW_READER);
1332 		idm_rc = idm_buf_tx_to_ini(iscsit_task->it_idm_task,
1333 		    ibuf->ibuf_idm_buf, dbuf->db_relative_offset,
1334 		    dbuf->db_data_size, &iscsit_buf_xfer_cb, dbuf);
1335 		rw_exit(&iscsit_task->it_ict->ict_sess->ist_sn_rwlock);
1336 
1337 		return (iscsit_idm_to_stmf(idm_rc));
1338 	} else if (dbuf->db_flags & DB_DIRECTION_FROM_RPORT) {
1339 		/* Grab the SN lock (see comment above) */
1340 		rw_enter(&iscsit_task->it_ict->ict_sess->ist_sn_rwlock,
1341 		    RW_READER);
1342 		idm_rc = idm_buf_rx_from_ini(iscsit_task->it_idm_task,
1343 		    ibuf->ibuf_idm_buf, dbuf->db_relative_offset,
1344 		    dbuf->db_data_size, &iscsit_buf_xfer_cb, dbuf);
1345 		rw_exit(&iscsit_task->it_ict->ict_sess->ist_sn_rwlock);
1346 
1347 		return (iscsit_idm_to_stmf(idm_rc));
1348 	}
1349 
1350 	/* What are we supposed to do if there is no direction? */
1351 	return (STMF_INVALID_ARG);
1352 }
1353 
1354 static void
1355 iscsit_buf_xfer_cb(idm_buf_t *idb, idm_status_t status)
1356 {
1357 	iscsit_task_t *itask = idb->idb_task_binding->idt_private;
1358 	stmf_data_buf_t *dbuf = idb->idb_cb_arg;
1359 
1360 	dbuf->db_xfer_status = iscsit_idm_to_stmf(status);
1361 
1362 	/*
1363 	 * If the task has been aborted then we don't need to call STMF
1364 	 */
1365 	if (itask->it_stmf_abort) {
1366 		return;
1367 	}
1368 
1369 	/*
1370 	 * COMSTAR currently requires port providers to support
1371 	 * the DB_SEND_STATUS_GOOD flag even if phase collapse is
1372 	 * not supported.  So we will roll our own... pretend we are
1373 	 * COMSTAR and ask for a status PDU.
1374 	 */
1375 	if ((dbuf->db_flags & DB_SEND_STATUS_GOOD) &&
1376 	    status == IDM_STATUS_SUCCESS) {
1377 		/*
1378 		 * If iscsit_send_scsi_status succeeds then the TX PDU
1379 		 * callback will call stmf_send_status_done and set
1380 		 * STMF_IOF_LPORT_DONE.  Consequently we don't need
1381 		 * to call stmf_data_xfer_done in that case.  We
1382 		 * still need to call it if we get a failure.
1383 		 *
1384 		 * To elaborate on this some more, upon successful
1385 		 * return from iscsit_send_scsi_status it's possible
1386 		 * that itask and idb have been freed and are no
1387 		 * longer valid.
1388 		 */
1389 		if (iscsit_send_scsi_status(itask->it_stmf_task, 0)
1390 		    != STMF_SUCCESS) {
1391 			/* Failed to send status */
1392 			dbuf->db_xfer_status = STMF_FAILURE;
1393 			stmf_data_xfer_done(itask->it_stmf_task, dbuf,
1394 			    STMF_IOF_LPORT_DONE);
1395 		}
1396 	} else {
1397 		stmf_data_xfer_done(itask->it_stmf_task, dbuf, 0);
1398 	}
1399 }
1400 
1401 
1402 /*ARGSUSED*/
1403 stmf_status_t
1404 iscsit_send_scsi_status(scsi_task_t *task, uint32_t ioflags)
1405 {
1406 	iscsit_task_t *itask = task->task_port_private;
1407 	iscsi_scsi_rsp_hdr_t *rsp;
1408 	idm_pdu_t *pdu;
1409 	int resp_datalen;
1410 
1411 	/*
1412 	 * If this task is aborted then we don't need to respond.
1413 	 */
1414 	if (itask->it_stmf_abort) {
1415 		return (STMF_SUCCESS);
1416 	}
1417 
1418 	/*
1419 	 * If this is a task management status, handle it elsewhere.
1420 	 */
1421 	if (task->task_mgmt_function != TM_NONE) {
1422 		/*
1423 		 * Don't wait for the PDU completion to tell STMF
1424 		 * the task is done -- it doesn't really matter and
1425 		 * it makes life complicated if STMF later asks us to
1426 		 * abort the request and we don't know whether the
1427 		 * status has been sent or not.
1428 		 */
1429 		itask->it_tm_responded = B_TRUE;
1430 		iscsit_send_task_mgmt_resp(itask->it_tm_pdu,
1431 		    (task->task_completion_status == STMF_SUCCESS) ?
1432 		    SCSI_TCP_TM_RESP_COMPLETE : SCSI_TCP_TM_RESP_FUNC_NOT_SUPP);
1433 		stmf_send_status_done(task, STMF_SUCCESS,
1434 		    STMF_IOF_LPORT_DONE);
1435 		return (STMF_SUCCESS);
1436 	}
1437 
1438 	/*
1439 	 * Remove the task from the session task list
1440 	 */
1441 	iscsit_task_done(itask);
1442 
1443 	/*
1444 	 * Send status
1445 	 */
1446 	mutex_enter(&itask->it_idm_task->idt_mutex);
1447 	if ((itask->it_idm_task->idt_state == TASK_ACTIVE) &&
1448 	    (task->task_completion_status == STMF_SUCCESS) &&
1449 	    (task->task_sense_length == 0) &&
1450 	    (task->task_resid == 0)) {
1451 		itask->it_idm_task->idt_state = TASK_COMPLETE;
1452 		/* PDU callback releases task hold */
1453 		idm_task_hold(itask->it_idm_task);
1454 		mutex_exit(&itask->it_idm_task->idt_mutex);
1455 		/*
1456 		 * Fast path.  Cached status PDU's are already
1457 		 * initialized.  We just need to fill in
1458 		 * connection and task information.
1459 		 */
1460 		pdu = kmem_cache_alloc(iscsit_status_pdu_cache, KM_SLEEP);
1461 		pdu->isp_ic = itask->it_ict->ict_ic;
1462 		pdu->isp_private = itask;
1463 
1464 		rsp = (iscsi_scsi_rsp_hdr_t *)pdu->isp_hdr;
1465 		rsp->itt = itask->it_itt;
1466 		rsp->cmd_status = task->task_scsi_status;
1467 		iscsit_pdu_tx(pdu);
1468 		return (STMF_SUCCESS);
1469 	} else {
1470 		if (itask->it_idm_task->idt_state != TASK_ACTIVE) {
1471 			mutex_exit(&itask->it_idm_task->idt_mutex);
1472 			return (STMF_FAILURE);
1473 		}
1474 		itask->it_idm_task->idt_state = TASK_COMPLETE;
1475 		/* PDU callback releases task hold */
1476 		idm_task_hold(itask->it_idm_task);
1477 		mutex_exit(&itask->it_idm_task->idt_mutex);
1478 
1479 		resp_datalen = (task->task_sense_length == 0) ? 0 :
1480 		    (task->task_sense_length + sizeof (uint16_t));
1481 
1482 		pdu = idm_pdu_alloc(sizeof (iscsi_hdr_t), resp_datalen);
1483 		idm_pdu_init(pdu, itask->it_ict->ict_ic, itask,
1484 		    iscsit_send_status_done);
1485 
1486 		rsp = (iscsi_scsi_rsp_hdr_t *)pdu->isp_hdr;
1487 		bzero(rsp, sizeof (*rsp));
1488 		rsp->opcode = ISCSI_OP_SCSI_RSP;
1489 
1490 		rsp->flags = ISCSI_FLAG_FINAL;
1491 		if (task->task_status_ctrl & TASK_SCTRL_OVER) {
1492 			rsp->flags |= ISCSI_FLAG_CMD_OVERFLOW;
1493 		} else if (task->task_status_ctrl & TASK_SCTRL_UNDER) {
1494 			rsp->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
1495 		}
1496 
1497 		rsp->bi_residual_count = 0;
1498 		rsp->residual_count = htonl(task->task_resid);
1499 		rsp->itt = itask->it_itt;
1500 		rsp->response = ISCSI_STATUS_CMD_COMPLETED;
1501 		rsp->cmd_status = task->task_scsi_status;
1502 		if (task->task_sense_length != 0) {
1503 			/*
1504 			 * Add a byte to provide the sense length in
1505 			 * the response
1506 			 */
1507 			*(uint16_t *)((void *)pdu->isp_data) =
1508 			    htons(task->task_sense_length);
1509 			bcopy(task->task_sense_data,
1510 			    (uint8_t *)pdu->isp_data +
1511 			    sizeof (uint16_t),
1512 			    task->task_sense_length);
1513 			hton24(rsp->dlength, resp_datalen);
1514 		}
1515 
1516 		DTRACE_PROBE5(iscsi__scsi__response,
1517 		    iscsit_conn_t *, itask->it_ict,
1518 		    uint8_t, rsp->response,
1519 		    uint8_t, rsp->cmd_status,
1520 		    idm_pdu_t *, pdu,
1521 		    scsi_task_t *, task);
1522 
1523 		iscsit_pdu_tx(pdu);
1524 
1525 		return (STMF_SUCCESS);
1526 	}
1527 }
1528 
1529 /*ARGSUSED*/
1530 static void
1531 iscsit_send_good_status_done(idm_pdu_t *pdu, idm_status_t status)
1532 {
1533 	iscsit_task_t	*itask;
1534 	boolean_t	aborted;
1535 
1536 	itask = pdu->isp_private;
1537 	aborted = itask->it_stmf_abort;
1538 
1539 	/*
1540 	 * After releasing the hold the task may be freed at any time so
1541 	 * don't touch it.
1542 	 */
1543 	idm_task_rele(itask->it_idm_task);
1544 	if (!aborted) {
1545 		stmf_send_status_done(itask->it_stmf_task,
1546 		    iscsit_idm_to_stmf(pdu->isp_status), STMF_IOF_LPORT_DONE);
1547 	}
1548 	kmem_cache_free(iscsit_status_pdu_cache, pdu);
1549 }
1550 
1551 /*ARGSUSED*/
1552 static void
1553 iscsit_send_status_done(idm_pdu_t *pdu, idm_status_t status)
1554 {
1555 	iscsit_task_t	 *itask;
1556 	boolean_t	aborted;
1557 
1558 	itask = pdu->isp_private;
1559 	aborted = itask->it_stmf_abort;
1560 
1561 	/*
1562 	 * After releasing the hold the task may be freed at any time so
1563 	 * don't touch it.
1564 	 */
1565 	idm_task_rele(itask->it_idm_task);
1566 	if (!aborted) {
1567 		stmf_send_status_done(itask->it_stmf_task,
1568 		    iscsit_idm_to_stmf(pdu->isp_status), STMF_IOF_LPORT_DONE);
1569 	}
1570 	idm_pdu_free(pdu);
1571 }
1572 
1573 
1574 void
1575 iscsit_lport_task_free(scsi_task_t *task)
1576 {
1577 	iscsit_task_t *itask = task->task_port_private;
1578 
1579 	/* We only call idm_task_start for regular tasks, not task management */
1580 	if (task->task_mgmt_function == TM_NONE) {
1581 		idm_task_done(itask->it_idm_task);
1582 		iscsit_task_free(itask);
1583 		return;
1584 	} else {
1585 		iscsit_tm_task_free(itask);
1586 	}
1587 }
1588 
1589 /*ARGSUSED*/
1590 stmf_status_t
1591 iscsit_abort(stmf_local_port_t *lport, int abort_cmd, void *arg, uint32_t flags)
1592 {
1593 	scsi_task_t	*st = (scsi_task_t *)arg;
1594 	iscsit_task_t	*iscsit_task;
1595 	idm_task_t	*idt;
1596 
1597 	/*
1598 	 * If this is a task management request then there's really not much to
1599 	 * do.
1600 	 */
1601 	if (st->task_mgmt_function != TM_NONE) {
1602 		return (STMF_ABORT_SUCCESS);
1603 	}
1604 
1605 	/*
1606 	 * Regular task, start cleaning up
1607 	 */
1608 	iscsit_task = st->task_port_private;
1609 	idt = iscsit_task->it_idm_task;
1610 	mutex_enter(&iscsit_task->it_mutex);
1611 	iscsit_task->it_stmf_abort = B_TRUE;
1612 	if (iscsit_task->it_aborted) {
1613 		mutex_exit(&iscsit_task->it_mutex);
1614 		/*
1615 		 * Task is no longer active
1616 		 */
1617 		iscsit_task_done(iscsit_task);
1618 
1619 		/*
1620 		 * STMF specification is wrong... says to return
1621 		 * STMF_ABORTED, the code actually looks for
1622 		 * STMF_ABORT_SUCCESS.
1623 		 */
1624 		return (STMF_ABORT_SUCCESS);
1625 	} else {
1626 		mutex_exit(&iscsit_task->it_mutex);
1627 		/*
1628 		 * Call IDM to abort the task.  Due to a variety of
1629 		 * circumstances the task may already be in the process of
1630 		 * aborting.
1631 		 * We'll let IDM worry about rationalizing all that except
1632 		 * for one particular instance.  If the state of the task
1633 		 * is TASK_COMPLETE, we need to indicate to the framework
1634 		 * that we are in fact done.  This typically happens with
1635 		 * framework-initiated task management type requests
1636 		 * (e.g. abort task).
1637 		 */
1638 		if (idt->idt_state == TASK_COMPLETE) {
1639 			idm_refcnt_wait_ref(&idt->idt_refcnt);
1640 			return (STMF_ABORT_SUCCESS);
1641 		} else {
1642 			idm_task_abort(idt->idt_ic, idt, AT_TASK_MGMT_ABORT);
1643 			return (STMF_SUCCESS);
1644 		}
1645 	}
1646 
1647 	/*NOTREACHED*/
1648 }
1649 
1650 /*ARGSUSED*/
1651 void
1652 iscsit_ctl(stmf_local_port_t *lport, int cmd, void *arg)
1653 {
1654 	iscsit_tgt_t		*iscsit_tgt;
1655 
1656 	ASSERT((cmd == STMF_CMD_LPORT_ONLINE) ||
1657 	    (cmd == STMF_ACK_LPORT_ONLINE_COMPLETE) ||
1658 	    (cmd == STMF_CMD_LPORT_OFFLINE) ||
1659 	    (cmd == STMF_ACK_LPORT_OFFLINE_COMPLETE));
1660 
1661 	iscsit_tgt = (iscsit_tgt_t *)lport->lport_port_private;
1662 
1663 	switch (cmd) {
1664 	case STMF_CMD_LPORT_ONLINE:
1665 		iscsit_tgt_sm_event(iscsit_tgt, TE_STMF_ONLINE_REQ);
1666 		break;
1667 	case STMF_CMD_LPORT_OFFLINE:
1668 		iscsit_tgt_sm_event(iscsit_tgt, TE_STMF_OFFLINE_REQ);
1669 		break;
1670 	case STMF_ACK_LPORT_ONLINE_COMPLETE:
1671 		iscsit_tgt_sm_event(iscsit_tgt, TE_STMF_ONLINE_COMPLETE_ACK);
1672 		break;
1673 	case STMF_ACK_LPORT_OFFLINE_COMPLETE:
1674 		iscsit_tgt_sm_event(iscsit_tgt, TE_STMF_OFFLINE_COMPLETE_ACK);
1675 		break;
1676 
1677 	default:
1678 		break;
1679 	}
1680 }
1681 
1682 static stmf_status_t
1683 iscsit_idm_to_stmf(idm_status_t idmrc)
1684 {
1685 	switch (idmrc) {
1686 	case IDM_STATUS_SUCCESS:
1687 		return (STMF_SUCCESS);
1688 	default:
1689 		return (STMF_FAILURE);
1690 	}
1691 	/*NOTREACHED*/
1692 }
1693 
1694 
1695 /*
1696  * ISCSI protocol
1697  */
1698 
1699 void
1700 iscsit_op_scsi_cmd(idm_conn_t *ic, idm_pdu_t *rx_pdu)
1701 {
1702 	iscsit_conn_t		*ict;
1703 	iscsit_task_t		*itask;
1704 	scsi_task_t		*task;
1705 	iscsit_buf_t		*ibuf;
1706 	iscsi_scsi_cmd_hdr_t	*iscsi_scsi =
1707 	    (iscsi_scsi_cmd_hdr_t *)rx_pdu->isp_hdr;
1708 	iscsi_addl_hdr_t	*ahs_hdr;
1709 	uint16_t		addl_cdb_len = 0;
1710 
1711 	ict = ic->ic_handle;
1712 
1713 	itask = iscsit_task_alloc(ict);
1714 	if (itask == NULL) {
1715 		/* Finish processing request */
1716 		iscsit_set_cmdsn(ict, rx_pdu);
1717 
1718 		iscsit_send_direct_scsi_resp(ict, rx_pdu,
1719 		    ISCSI_STATUS_CMD_COMPLETED, STATUS_BUSY);
1720 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
1721 		return;
1722 	}
1723 
1724 
1725 	/*
1726 	 * Note CmdSN and ITT in task.  IDM will have already validated this
1727 	 * request against the connection state so we don't need to check
1728 	 * that (the connection may have changed state in the meantime but
1729 	 * we will catch that when we try to send a response)
1730 	 */
1731 	itask->it_cmdsn = ntohl(iscsi_scsi->cmdsn);
1732 	itask->it_itt = iscsi_scsi->itt;
1733 
1734 	/*
1735 	 * Check for extended CDB AHS
1736 	 */
1737 	if (iscsi_scsi->hlength > 0) {
1738 		ahs_hdr = (iscsi_addl_hdr_t *)iscsi_scsi;
1739 		addl_cdb_len = ((ahs_hdr->ahs_hlen_hi << 8) |
1740 		    ahs_hdr->ahs_hlen_lo) - 1; /* Adjust for reserved byte */
1741 		if (((addl_cdb_len + 4) / sizeof (uint32_t)) >
1742 		    iscsi_scsi->hlength) {
1743 			/* Mangled header info, drop it */
1744 			idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
1745 			return;
1746 		}
1747 	}
1748 
1749 	ict = rx_pdu->isp_ic->ic_handle; /* IDM client private */
1750 
1751 	/*
1752 	 * Add task to session list.  This function will also check to
1753 	 * ensure that the task does not already exist.
1754 	 */
1755 	if (iscsit_task_start(itask) != IDM_STATUS_SUCCESS) {
1756 		/*
1757 		 * Task exists, free all resources and reject.  Don't
1758 		 * update expcmdsn in this case because RFC 3720 says
1759 		 * "The CmdSN of the rejected command PDU (if it is a
1760 		 * non-immediate command) MUST NOT be considered received
1761 		 * by the target (i.e., a command sequence gap must be
1762 		 * assumed for the CmdSN), even though the CmdSN of the
1763 		 * rejected command PDU may be reliably ascertained.  Upon
1764 		 * receiving the Reject, the initiator MUST plug the CmdSN
1765 		 * gap in order to continue to use the session.  The gap
1766 		 * may be plugged either by transmitting a command PDU
1767 		 * with the same CmdSN, or by aborting the task (see section
1768 		 * 6.9 on how an abort may plug a CmdSN gap)." (Section 6.3)
1769 		 */
1770 		iscsit_task_free(itask);
1771 		iscsit_send_reject(ict, rx_pdu, ISCSI_REJECT_TASK_IN_PROGRESS);
1772 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
1773 		return;
1774 	}
1775 
1776 	/* Update sequence numbers */
1777 	iscsit_set_cmdsn(ict, rx_pdu);
1778 
1779 	/*
1780 	 * Allocate STMF task
1781 	 */
1782 	itask->it_stmf_task = stmf_task_alloc(
1783 	    itask->it_ict->ict_sess->ist_lport,
1784 	    itask->it_ict->ict_sess->ist_stmf_sess, iscsi_scsi->lun,
1785 	    16 + addl_cdb_len, 0);
1786 	if (itask->it_stmf_task == NULL) {
1787 		/*
1788 		 * Either stmf really couldn't get memory for a task or,
1789 		 * more likely, the LU is currently in reset.  Either way
1790 		 * we have no choice but to fail the request.
1791 		 */
1792 		iscsit_task_done(itask);
1793 		iscsit_task_free(itask);
1794 		iscsit_send_direct_scsi_resp(ict, rx_pdu,
1795 		    ISCSI_STATUS_CMD_COMPLETED, STATUS_BUSY);
1796 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
1797 		return;
1798 	}
1799 
1800 	task = itask->it_stmf_task;
1801 	task->task_port_private = itask;
1802 
1803 	bcopy(iscsi_scsi->lun, task->task_lun_no, sizeof (task->task_lun_no));
1804 
1805 	/*
1806 	 * iSCSI and Comstar use the same values.  Should we rely on this
1807 	 * or translate them bit-wise?
1808 	 */
1809 
1810 	task->task_flags =
1811 	    (((iscsi_scsi->flags & ISCSI_FLAG_CMD_READ) ? TF_READ_DATA : 0) |
1812 	    ((iscsi_scsi->flags & ISCSI_FLAG_CMD_WRITE) ? TF_WRITE_DATA : 0) |
1813 	    ((rx_pdu->isp_datalen == 0) ? 0 : TF_INITIAL_BURST));
1814 
1815 	switch (iscsi_scsi->flags & ISCSI_FLAG_CMD_ATTR_MASK) {
1816 	case ISCSI_ATTR_UNTAGGED:
1817 		break;
1818 	case ISCSI_ATTR_SIMPLE:
1819 		task->task_additional_flags |= TF_ATTR_SIMPLE_QUEUE;
1820 		break;
1821 	case ISCSI_ATTR_ORDERED:
1822 		task->task_additional_flags |= TF_ATTR_ORDERED_QUEUE;
1823 		break;
1824 	case ISCSI_ATTR_HEAD_OF_QUEUE:
1825 		task->task_additional_flags |= TF_ATTR_HEAD_OF_QUEUE;
1826 		break;
1827 	case ISCSI_ATTR_ACA:
1828 		task->task_additional_flags |= TF_ATTR_ACA;
1829 		break;
1830 	default:
1831 		/* Protocol error but just take it, treat as untagged */
1832 		break;
1833 	}
1834 
1835 
1836 	task->task_additional_flags = 0;
1837 	task->task_priority = 0;
1838 	task->task_mgmt_function = TM_NONE;
1839 
1840 	/*
1841 	 * This "task_max_nbufs" doesn't map well to BIDI.  We probably need
1842 	 * parameter for each direction.  "MaxOutstandingR2T" may very well
1843 	 * be set to one which could prevent us from doing simultaneous
1844 	 * transfers in each direction.
1845 	 */
1846 	task->task_max_nbufs = (iscsi_scsi->flags & ISCSI_FLAG_CMD_WRITE) ?
1847 	    ict->ict_op.op_max_outstanding_r2t : STMF_BUFS_MAX;
1848 	task->task_cmd_seq_no = ntohl(iscsi_scsi->itt);
1849 	task->task_expected_xfer_length = ntohl(iscsi_scsi->data_length);
1850 
1851 	/* Copy CDB */
1852 	bcopy(iscsi_scsi->scb, task->task_cdb, 16);
1853 	if (addl_cdb_len > 0) {
1854 		bcopy(ahs_hdr->ahs_extscb, task->task_cdb + 16, addl_cdb_len);
1855 	}
1856 
1857 	DTRACE_ISCSI_3(scsi__command, idm_conn_t *, ic,
1858 	    iscsi_scsi_cmd_hdr_t *, (iscsi_scsi_cmd_hdr_t *)rx_pdu->isp_hdr,
1859 	    scsi_task_t *, task);
1860 
1861 	/*
1862 	 * Copy the transport header into the task handle from the PDU
1863 	 * handle. The transport header describes this task's remote tagged
1864 	 * buffer.
1865 	 */
1866 	if (rx_pdu->isp_transport_hdrlen != 0) {
1867 		bcopy(rx_pdu->isp_transport_hdr,
1868 		    itask->it_idm_task->idt_transport_hdr,
1869 		    rx_pdu->isp_transport_hdrlen);
1870 	}
1871 
1872 	/*
1873 	 * Tell IDM about our new active task
1874 	 */
1875 	idm_task_start(itask->it_idm_task, (uintptr_t)itask->it_itt);
1876 
1877 	/*
1878 	 * If we have any immediate data then setup the immediate buffer
1879 	 * context that comes with the task
1880 	 */
1881 	if (rx_pdu->isp_datalen) {
1882 		ibuf = itask->it_immed_data;
1883 		ibuf->ibuf_immed_data_pdu = rx_pdu;
1884 		ibuf->ibuf_stmf_buf->db_data_size = rx_pdu->isp_datalen;
1885 		ibuf->ibuf_stmf_buf->db_buf_size = rx_pdu->isp_datalen;
1886 		ibuf->ibuf_stmf_buf->db_relative_offset = 0;
1887 		ibuf->ibuf_stmf_buf->db_sglist[0].seg_length =
1888 		    rx_pdu->isp_datalen;
1889 		ibuf->ibuf_stmf_buf->db_sglist[0].seg_addr = rx_pdu->isp_data;
1890 
1891 		DTRACE_ISCSI_8(xfer__start, idm_conn_t *, ic,
1892 		    uintptr_t, ibuf->ibuf_stmf_buf->db_sglist[0].seg_addr,
1893 		    uint32_t, ibuf->ibuf_stmf_buf->db_relative_offset,
1894 		    uint64_t, 0, uint32_t, 0, uint32_t, 0, /* no raddr */
1895 		    uint32_t, rx_pdu->isp_datalen, int, XFER_BUF_TX_TO_INI);
1896 
1897 		/*
1898 		 * For immediate data transfer, there is no callback from
1899 		 * stmf to indicate that the initial burst of data is
1900 		 * transferred successfully. In some cases, the task can
1901 		 * get freed before execution returns from stmf_post_task.
1902 		 * Although this xfer-start/done probe accurately tracks
1903 		 * the size of the transfer, it does only provide a best
1904 		 * effort on the timing of the transfer.
1905 		 */
1906 		DTRACE_ISCSI_8(xfer__done, idm_conn_t *, ic,
1907 		    uintptr_t, ibuf->ibuf_stmf_buf->db_sglist[0].seg_addr,
1908 		    uint32_t, ibuf->ibuf_stmf_buf->db_relative_offset,
1909 		    uint64_t, 0, uint32_t, 0, uint32_t, 0, /* no raddr */
1910 		    uint32_t, rx_pdu->isp_datalen, int, XFER_BUF_TX_TO_INI);
1911 
1912 		stmf_post_task(task, ibuf->ibuf_stmf_buf);
1913 	} else {
1914 
1915 		stmf_post_task(task, NULL);
1916 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
1917 	}
1918 }
1919 
1920 /*ARGSUSED*/
1921 void
1922 iscsit_deferred_dispatch(idm_pdu_t *rx_pdu)
1923 {
1924 	iscsit_conn_t *ict = rx_pdu->isp_ic->ic_handle;
1925 
1926 	/*
1927 	 * If the connection has been lost then ignore new PDU's
1928 	 */
1929 	mutex_enter(&ict->ict_mutex);
1930 	if (ict->ict_lost) {
1931 		mutex_exit(&ict->ict_mutex);
1932 		idm_pdu_complete(rx_pdu, IDM_STATUS_FAIL);
1933 		return;
1934 	}
1935 
1936 	/*
1937 	 * Grab a hold on the connection to prevent it from going away
1938 	 * between now and when the taskq function is called.
1939 	 */
1940 	iscsit_conn_dispatch_hold(ict);
1941 	mutex_exit(&ict->ict_mutex);
1942 
1943 	if (taskq_dispatch(iscsit_global.global_dispatch_taskq,
1944 	    iscsit_deferred, rx_pdu, DDI_NOSLEEP) == NULL) {
1945 		/*
1946 		 * In the unlikely scenario that we couldn't get the resources
1947 		 * to dispatch the PDU then just drop it.
1948 		 */
1949 		idm_pdu_complete(rx_pdu, IDM_STATUS_FAIL);
1950 		idm_conn_event(ict->ict_ic, CE_TRANSPORT_FAIL, NULL);
1951 		iscsit_conn_dispatch_rele(ict);
1952 	}
1953 }
1954 
1955 static void
1956 iscsit_deferred(void *rx_pdu_void)
1957 {
1958 	idm_pdu_t *rx_pdu = rx_pdu_void;
1959 	idm_conn_t *ic = rx_pdu->isp_ic;
1960 	iscsit_conn_t *ict = ic->ic_handle;
1961 
1962 	switch (IDM_PDU_OPCODE(rx_pdu)) {
1963 	case ISCSI_OP_NOOP_OUT:
1964 		iscsit_set_cmdsn(ict, rx_pdu);
1965 		iscsit_pdu_op_noop(ict, rx_pdu);
1966 		break;
1967 	case ISCSI_OP_LOGIN_CMD:
1968 		iscsit_pdu_op_login_cmd(ict, rx_pdu);
1969 		break;
1970 	case ISCSI_OP_TEXT_CMD:
1971 		iscsit_set_cmdsn(ict, rx_pdu);
1972 		iscsit_pdu_op_text_cmd(ict, rx_pdu);
1973 		break;
1974 	case ISCSI_OP_LOGOUT_CMD:
1975 		iscsit_set_cmdsn(ict, rx_pdu);
1976 		iscsit_pdu_op_logout_cmd(ict, rx_pdu);
1977 		break;
1978 	default:
1979 		/* Protocol error.  IDM should have caught this */
1980 		idm_pdu_complete(rx_pdu, IDM_STATUS_FAIL);
1981 		ASSERT(0);
1982 		break;
1983 	}
1984 
1985 	iscsit_conn_dispatch_rele(ict);
1986 }
1987 
1988 static void
1989 iscsit_send_direct_scsi_resp(iscsit_conn_t *ict, idm_pdu_t *rx_pdu,
1990     uint8_t response, uint8_t cmd_status)
1991 {
1992 	idm_pdu_t			*rsp_pdu;
1993 	idm_conn_t			*ic;
1994 	iscsi_scsi_rsp_hdr_t		*resp;
1995 	iscsi_scsi_cmd_hdr_t		*req =
1996 	    (iscsi_scsi_cmd_hdr_t *)rx_pdu->isp_hdr;
1997 
1998 	ic = ict->ict_ic;
1999 
2000 	rsp_pdu = idm_pdu_alloc(sizeof (iscsi_scsi_rsp_hdr_t), 0);
2001 	idm_pdu_init(rsp_pdu, ic, NULL, NULL);
2002 	resp = (iscsi_scsi_rsp_hdr_t *)rsp_pdu->isp_hdr;
2003 
2004 	resp->opcode = ISCSI_OP_SCSI_RSP;
2005 	resp->flags = ISCSI_FLAG_FINAL;
2006 	resp->response = response;
2007 	resp->cmd_status = cmd_status;
2008 	resp->itt = req->itt;
2009 	if ((response == ISCSI_STATUS_CMD_COMPLETED) &&
2010 	    (req->data_length != 0) &&
2011 	    ((req->flags & ISCSI_FLAG_CMD_READ) ||
2012 	    (req->flags & ISCSI_FLAG_CMD_WRITE))) {
2013 		resp->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
2014 		resp->residual_count = req->data_length;
2015 	}
2016 
2017 	DTRACE_PROBE4(iscsi__scsi__direct__response,
2018 	    iscsit_conn_t *, ict,
2019 	    uint8_t, resp->response,
2020 	    uint8_t, resp->cmd_status,
2021 	    idm_pdu_t *, rsp_pdu);
2022 
2023 	iscsit_pdu_tx(rsp_pdu);
2024 }
2025 
2026 void
2027 iscsit_send_task_mgmt_resp(idm_pdu_t *tm_resp_pdu, uint8_t tm_status)
2028 {
2029 	iscsi_scsi_task_mgt_rsp_hdr_t	*tm_resp;
2030 
2031 	tm_resp = (iscsi_scsi_task_mgt_rsp_hdr_t *)tm_resp_pdu->isp_hdr;
2032 	tm_resp->response = tm_status;
2033 
2034 	DTRACE_PROBE3(iscsi__scsi__tm__response,
2035 	    iscsit_conn_t *, tm_resp_pdu->isp_ic->ic_handle,
2036 	    uint8_t, tm_resp->response,
2037 	    idm_pdu_t *, tm_resp_pdu);
2038 	iscsit_pdu_tx(tm_resp_pdu);
2039 }
2040 
2041 void
2042 iscsit_op_scsi_task_mgmt(iscsit_conn_t *ict, idm_pdu_t *rx_pdu)
2043 {
2044 	idm_pdu_t			*tm_resp_pdu;
2045 	iscsit_task_t			*itask;
2046 	iscsit_task_t			*tm_itask;
2047 	scsi_task_t			*task;
2048 	iscsi_scsi_task_mgt_hdr_t 	*iscsi_tm =
2049 	    (iscsi_scsi_task_mgt_hdr_t *)rx_pdu->isp_hdr;
2050 	iscsi_scsi_task_mgt_rsp_hdr_t 	*iscsi_tm_rsp =
2051 	    (iscsi_scsi_task_mgt_rsp_hdr_t *)rx_pdu->isp_hdr;
2052 	uint32_t			rtt, cmdsn, refcmdsn;
2053 	uint8_t				tm_func;
2054 
2055 	/*
2056 	 * Setup response PDU (response field will get filled in later)
2057 	 */
2058 	tm_resp_pdu = idm_pdu_alloc(sizeof (iscsi_scsi_task_mgt_rsp_hdr_t), 0);
2059 	if (tm_resp_pdu == NULL) {
2060 		/* Can't respond, just drop it */
2061 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2062 		return;
2063 	}
2064 	idm_pdu_init(tm_resp_pdu, ict->ict_ic, NULL, NULL);
2065 	iscsi_tm_rsp = (iscsi_scsi_task_mgt_rsp_hdr_t *)tm_resp_pdu->isp_hdr;
2066 	bzero(iscsi_tm_rsp, sizeof (iscsi_scsi_task_mgt_rsp_hdr_t));
2067 	iscsi_tm_rsp->opcode = ISCSI_OP_SCSI_TASK_MGT_RSP;
2068 	iscsi_tm_rsp->flags = ISCSI_FLAG_FINAL;
2069 	iscsi_tm_rsp->itt = rx_pdu->isp_hdr->itt;
2070 
2071 	/*
2072 	 * Figure out what we're being asked to do.
2073 	 */
2074 	DTRACE_PROBE4(iscsi__scsi__tm__request,
2075 	    iscsit_conn_t *, ict,
2076 	    uint8_t, (iscsi_tm->function & ISCSI_FLAG_TASK_MGMT_FUNCTION_MASK),
2077 	    uint32_t, iscsi_tm->rtt,
2078 	    idm_pdu_t *, rx_pdu);
2079 	switch (iscsi_tm->function & ISCSI_FLAG_TASK_MGMT_FUNCTION_MASK) {
2080 	case ISCSI_TM_FUNC_ABORT_TASK:
2081 		/*
2082 		 * STMF doesn't currently support the "abort task" task
2083 		 * management command although it does support aborting
2084 		 * an individual task.  We'll get STMF to abort the task
2085 		 * for us but handle the details of the task management
2086 		 * command ourselves.
2087 		 *
2088 		 * Find the task associated with the referenced task tag.
2089 		 */
2090 		rtt = iscsi_tm->rtt;
2091 		itask = (iscsit_task_t *)idm_task_find_by_handle(ict->ict_ic,
2092 		    (uintptr_t)rtt);
2093 
2094 		if (itask == NULL) {
2095 			cmdsn = ntohl(iscsi_tm->cmdsn);
2096 			refcmdsn = ntohl(iscsi_tm->refcmdsn);
2097 
2098 			/*
2099 			 * Task was not found.  If RefCmdSN is within the CmdSN
2100 			 * window and less than CmdSN of the TM function, return
2101 			 * "Function Complete".  Otherwise, return
2102 			 * "Task Does Not Exist".
2103 			 */
2104 
2105 			if (iscsit_cmdsn_in_window(ict, refcmdsn) &&
2106 			    (refcmdsn < cmdsn)) {
2107 				iscsit_send_task_mgmt_resp(tm_resp_pdu,
2108 				    SCSI_TCP_TM_RESP_COMPLETE);
2109 			} else {
2110 				iscsit_send_task_mgmt_resp(tm_resp_pdu,
2111 				    SCSI_TCP_TM_RESP_NO_TASK);
2112 			}
2113 		} else {
2114 
2115 			/*
2116 			 * Tell STMF to abort the task.  This will do no harm
2117 			 * if the task is already complete.
2118 			 */
2119 			stmf_abort(STMF_QUEUE_TASK_ABORT, itask->it_stmf_task,
2120 			    STMF_ABORTED, NULL);
2121 
2122 			/*
2123 			 * Make sure the task hasn't already completed
2124 			 */
2125 			mutex_enter(&itask->it_idm_task->idt_mutex);
2126 			if ((itask->it_idm_task->idt_state == TASK_COMPLETE) ||
2127 			    (itask->it_idm_task->idt_state == TASK_IDLE)) {
2128 				/*
2129 				 * Task is complete, return "Task Does Not
2130 				 * Exist"
2131 				 */
2132 				mutex_exit(&itask->it_idm_task->idt_mutex);
2133 				iscsit_send_task_mgmt_resp(tm_resp_pdu,
2134 				    SCSI_TCP_TM_RESP_NO_TASK);
2135 			} else {
2136 				/*
2137 				 * STMF is now aborting the task, return
2138 				 * "Function Complete"
2139 				 */
2140 				mutex_exit(&itask->it_idm_task->idt_mutex);
2141 				iscsit_send_task_mgmt_resp(tm_resp_pdu,
2142 				    SCSI_TCP_TM_RESP_COMPLETE);
2143 			}
2144 			idm_task_rele(itask->it_idm_task);
2145 		}
2146 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2147 		return;
2148 
2149 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2150 		tm_func = TM_ABORT_TASK_SET;
2151 		break;
2152 
2153 	case ISCSI_TM_FUNC_CLEAR_ACA:
2154 		tm_func = TM_CLEAR_ACA;
2155 		break;
2156 
2157 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2158 		tm_func = TM_CLEAR_TASK_SET;
2159 		break;
2160 
2161 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2162 		tm_func = TM_LUN_RESET;
2163 		break;
2164 
2165 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2166 		tm_func = TM_TARGET_WARM_RESET;
2167 		break;
2168 
2169 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2170 		tm_func = TM_TARGET_COLD_RESET;
2171 		break;
2172 
2173 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2174 		/*
2175 		 * We do not currently support allegiance reassignment.  When
2176 		 * we start supporting ERL1+, we will need to.
2177 		 */
2178 		iscsit_send_task_mgmt_resp(tm_resp_pdu,
2179 		    SCSI_TCP_TM_RESP_NO_ALLG_REASSN);
2180 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2181 		return;
2182 
2183 	default:
2184 		iscsit_send_task_mgmt_resp(tm_resp_pdu,
2185 		    SCSI_TCP_TM_RESP_REJECTED);
2186 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2187 		return;
2188 	}
2189 
2190 	tm_itask = iscsit_tm_task_alloc(ict);
2191 	if (tm_itask == NULL) {
2192 		iscsit_send_task_mgmt_resp(tm_resp_pdu,
2193 		    SCSI_TCP_TM_RESP_REJECTED);
2194 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2195 		return;
2196 	}
2197 
2198 
2199 	task = stmf_task_alloc(ict->ict_sess->ist_lport,
2200 	    ict->ict_sess->ist_stmf_sess, iscsi_tm->lun,
2201 	    0, STMF_TASK_EXT_NONE);
2202 	if (task == NULL) {
2203 		/*
2204 		 * If this happens, either the LU is in reset, couldn't
2205 		 * get memory, or some other condition in which we simply
2206 		 * can't complete this request.  It would be nice to return
2207 		 * an error code like "busy" but the closest we have is
2208 		 * "rejected".
2209 		 */
2210 		iscsit_send_task_mgmt_resp(tm_resp_pdu,
2211 		    SCSI_TCP_TM_RESP_REJECTED);
2212 		iscsit_tm_task_free(tm_itask);
2213 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2214 		return;
2215 	}
2216 
2217 	tm_itask->it_tm_pdu = tm_resp_pdu;
2218 	tm_itask->it_stmf_task = task;
2219 	task->task_port_private = tm_itask;
2220 	task->task_mgmt_function = tm_func;
2221 	task->task_additional_flags = TASK_AF_NO_EXPECTED_XFER_LENGTH;
2222 	task->task_priority = 0;
2223 	task->task_max_nbufs = STMF_BUFS_MAX;
2224 	task->task_cmd_seq_no = iscsi_tm->itt;
2225 	task->task_expected_xfer_length = 0;
2226 
2227 	stmf_post_task(task, NULL);
2228 	idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2229 }
2230 
2231 static void
2232 iscsit_pdu_op_noop(iscsit_conn_t *ict, idm_pdu_t *rx_pdu)
2233 {
2234 	iscsi_nop_out_hdr_t *out = (iscsi_nop_out_hdr_t *)rx_pdu->isp_hdr;
2235 	iscsi_nop_in_hdr_t *in;
2236 	int resp_datalen;
2237 	idm_pdu_t *resp;
2238 
2239 	/* Ignore the response from initiator */
2240 	if ((out->itt == ISCSI_RSVD_TASK_TAG) ||
2241 	    (out->ttt != ISCSI_RSVD_TASK_TAG)) {
2242 		idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2243 		return;
2244 	}
2245 
2246 	/* Allocate a PDU to respond */
2247 	resp_datalen = ntoh24(out->dlength);
2248 	resp = idm_pdu_alloc(sizeof (iscsi_hdr_t), resp_datalen);
2249 	idm_pdu_init(resp, ict->ict_ic, NULL, NULL);
2250 	if (resp_datalen > 0) {
2251 		bcopy(rx_pdu->isp_data, resp->isp_data, resp_datalen);
2252 	}
2253 
2254 	in = (iscsi_nop_in_hdr_t *)resp->isp_hdr;
2255 	bzero(in, sizeof (*in));
2256 	in->opcode = ISCSI_OP_NOOP_IN;
2257 	in->flags = ISCSI_FLAG_FINAL;
2258 	bcopy(out->lun, in->lun, 8);
2259 	in->itt		= out->itt;
2260 	in->ttt		= ISCSI_RSVD_TASK_TAG;
2261 	hton24(in->dlength, resp_datalen);
2262 
2263 	/* Any other field in resp to be set? */
2264 	iscsit_pdu_tx(resp);
2265 	idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2266 }
2267 
2268 static void
2269 iscsit_pdu_op_login_cmd(iscsit_conn_t	*ict, idm_pdu_t *rx_pdu)
2270 {
2271 
2272 	/*
2273 	 * Submit PDU to login state machine.  State machine will free the
2274 	 * PDU.
2275 	 */
2276 	iscsit_login_sm_event(ict, ILE_LOGIN_RCV, rx_pdu);
2277 }
2278 
2279 void
2280 iscsit_pdu_op_logout_cmd(iscsit_conn_t	*ict, idm_pdu_t *rx_pdu)
2281 {
2282 	iscsi_logout_hdr_t 	*logout_req =
2283 	    (iscsi_logout_hdr_t *)rx_pdu->isp_hdr;
2284 	iscsi_logout_rsp_hdr_t	*logout_rsp;
2285 	idm_pdu_t *resp;
2286 
2287 	/* Allocate a PDU to respond */
2288 	resp = idm_pdu_alloc(sizeof (iscsi_hdr_t), 0);
2289 	idm_pdu_init(resp, ict->ict_ic, NULL, NULL);
2290 
2291 	/*
2292 	 * Logout results in the immediate termination of all tasks except
2293 	 * if the logout reason is ISCSI_LOGOUT_REASON_RECOVERY.  The
2294 	 * connection state machine will drive this task cleanup automatically
2295 	 * so we don't need to handle that here.
2296 	 */
2297 	logout_rsp = (iscsi_logout_rsp_hdr_t *)resp->isp_hdr;
2298 	bzero(logout_rsp, sizeof (*logout_rsp));
2299 	logout_rsp->opcode = ISCSI_OP_LOGOUT_RSP;
2300 	logout_rsp->flags = ISCSI_FLAG_FINAL;
2301 	logout_rsp->itt = logout_req->itt;
2302 	if ((logout_req->flags & ISCSI_FLAG_LOGOUT_REASON_MASK) >
2303 	    ISCSI_LOGOUT_REASON_RECOVERY) {
2304 		logout_rsp->response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2305 	} else {
2306 		logout_rsp->response = ISCSI_LOGOUT_SUCCESS;
2307 	}
2308 
2309 	iscsit_pdu_tx(resp);
2310 	idm_pdu_complete(rx_pdu, IDM_STATUS_SUCCESS);
2311 }
2312 
2313 /*
2314  * Calculate the number of outstanding commands we can process
2315  */
2316 int
2317 iscsit_cmd_window()
2318 {
2319 	/* Will be better later */
2320 	return	(1024);
2321 }
2322 
2323 /*
2324  * Set local registers based on incoming PDU
2325  */
2326 void
2327 iscsit_set_cmdsn(iscsit_conn_t *ict, idm_pdu_t *rx_pdu)
2328 {
2329 	iscsit_sess_t *ist;
2330 	iscsi_scsi_cmd_hdr_t *req;
2331 
2332 	ist = ict->ict_sess;
2333 
2334 	req = (iscsi_scsi_cmd_hdr_t *)rx_pdu->isp_hdr;
2335 
2336 	rw_enter(&ist->ist_sn_rwlock, RW_WRITER);
2337 	ist->ist_expcmdsn = ntohl(req->cmdsn) + 1;
2338 	ist->ist_maxcmdsn = ntohl(req->cmdsn) + iscsit_cmd_window();
2339 	rw_exit(&ist->ist_sn_rwlock);
2340 }
2341 
2342 /*
2343  * Update local StatSN and set SNs in response
2344  */
2345 static void
2346 iscsit_calc_rspsn(iscsit_conn_t *ict, idm_pdu_t *resp)
2347 {
2348 	iscsit_sess_t *ist;
2349 	iscsi_scsi_rsp_hdr_t *rsp;
2350 
2351 	/* Get iSCSI session handle */
2352 	ist = ict->ict_sess;
2353 
2354 	rsp = (iscsi_scsi_rsp_hdr_t *)resp->isp_hdr;
2355 
2356 	/* Update StatSN */
2357 	rsp->statsn = htonl(ict->ict_statsn);
2358 	switch (IDM_PDU_OPCODE(resp)) {
2359 	case ISCSI_OP_RTT_RSP:
2360 		/* Do nothing */
2361 		break;
2362 	case ISCSI_OP_NOOP_IN:
2363 		/*
2364 		 * Refer to section 10.19.1, RFC3720.
2365 		 * Advance only if target is responding initiator
2366 		 */
2367 		if (((iscsi_nop_in_hdr_t *)rsp)->ttt == ISCSI_RSVD_TASK_TAG)
2368 			ict->ict_statsn++;
2369 		break;
2370 	case ISCSI_OP_SCSI_DATA_RSP:
2371 		if (rsp->flags & ISCSI_FLAG_DATA_STATUS)
2372 			ict->ict_statsn++;
2373 		else
2374 			rsp->statsn = 0;
2375 		break;
2376 	default:
2377 		ict->ict_statsn++;
2378 		break;
2379 	}
2380 
2381 	/* Set ExpCmdSN and MaxCmdSN */
2382 	rsp->maxcmdsn = htonl(ist->ist_maxcmdsn);
2383 	rsp->expcmdsn = htonl(ist->ist_expcmdsn);
2384 }
2385 
2386 /*
2387  * Wrapper funtion, calls iscsi_calc_rspsn and idm_pdu_tx
2388  */
2389 void
2390 iscsit_pdu_tx(idm_pdu_t *pdu)
2391 {
2392 	iscsit_conn_t *ict = pdu->isp_ic->ic_handle;
2393 
2394 	/*
2395 	 * Protect ict->ict_statsn, ist->ist_maxcmdsn, and ist->ist_expcmdsn
2396 	 * (which are used by iscsit_calc_rspsn) with the session mutex
2397 	 * (ist->ist_sn_mutex).
2398 	 */
2399 	rw_enter(&ict->ict_sess->ist_sn_rwlock, RW_WRITER);
2400 	iscsit_calc_rspsn(ict, pdu);
2401 	idm_pdu_tx(pdu);
2402 	rw_exit(&ict->ict_sess->ist_sn_rwlock);
2403 }
2404 
2405 /*
2406  * Internal functions
2407  */
2408 
2409 void
2410 iscsit_send_async_event(iscsit_conn_t *ict, uint8_t event)
2411 {
2412 	idm_pdu_t		*abt;
2413 	iscsi_async_evt_hdr_t	*async_abt;
2414 
2415 	/*
2416 	 * Get a PDU to build the abort request.
2417 	 */
2418 	abt = idm_pdu_alloc(sizeof (iscsi_hdr_t), 0);
2419 	if (abt == NULL) {
2420 		idm_conn_event(ict->ict_ic, CE_TRANSPORT_FAIL, NULL);
2421 		return;
2422 	}
2423 
2424 	idm_pdu_init(abt, ict->ict_ic, NULL, NULL);
2425 	abt->isp_datalen = 0;
2426 
2427 	async_abt = (iscsi_async_evt_hdr_t *)abt->isp_hdr;
2428 	bzero(async_abt, sizeof (*async_abt));
2429 	async_abt->opcode = ISCSI_OP_ASYNC_EVENT;
2430 	async_abt->async_event = event;
2431 	async_abt->flags = ISCSI_FLAG_FINAL;
2432 	async_abt->rsvd4[0] = 0xff;
2433 	async_abt->rsvd4[1] = 0xff;
2434 	async_abt->rsvd4[2] = 0xff;
2435 	async_abt->rsvd4[3] = 0xff;
2436 
2437 	switch (event) {
2438 	case ISCSI_ASYNC_EVENT_REQUEST_LOGOUT:
2439 		async_abt->param3 = htons(IDM_LOGOUT_SECONDS);
2440 		break;
2441 	case ISCSI_ASYNC_EVENT_SCSI_EVENT:
2442 	case ISCSI_ASYNC_EVENT_DROPPING_CONNECTION:
2443 	case ISCSI_ASYNC_EVENT_DROPPING_ALL_CONNECTIONS:
2444 	case ISCSI_ASYNC_EVENT_PARAM_NEGOTIATION:
2445 	default:
2446 		ASSERT(0);
2447 	}
2448 
2449 	iscsit_pdu_tx(abt);
2450 }
2451 
2452 void
2453 iscsit_send_reject(iscsit_conn_t *ict, idm_pdu_t *rejected_pdu, uint8_t reason)
2454 {
2455 	idm_pdu_t		*reject_pdu;
2456 	iscsi_reject_rsp_hdr_t	*reject;
2457 
2458 	/*
2459 	 * Get a PDU to build the abort request.
2460 	 */
2461 	reject_pdu = idm_pdu_alloc(sizeof (iscsi_hdr_t),
2462 	    rejected_pdu->isp_hdrlen);
2463 	if (reject_pdu == NULL) {
2464 		idm_conn_event(ict->ict_ic, CE_TRANSPORT_FAIL, NULL);
2465 		return;
2466 	}
2467 	idm_pdu_init(reject_pdu, ict->ict_ic, NULL, NULL);
2468 
2469 	reject_pdu->isp_datalen = rejected_pdu->isp_hdrlen;
2470 	bcopy(rejected_pdu->isp_hdr, reject_pdu->isp_data,
2471 	    rejected_pdu->isp_hdrlen);
2472 
2473 	reject = (iscsi_reject_rsp_hdr_t *)reject_pdu->isp_hdr;
2474 	bzero(reject, sizeof (*reject));
2475 	reject->opcode = ISCSI_OP_REJECT_MSG;
2476 	reject->reason = reason;
2477 	reject->flags = ISCSI_FLAG_FINAL;
2478 	hton24(reject->dlength, rejected_pdu->isp_hdrlen);
2479 	reject->must_be_ff[0] = 0xff;
2480 	reject->must_be_ff[1] = 0xff;
2481 	reject->must_be_ff[2] = 0xff;
2482 	reject->must_be_ff[3] = 0xff;
2483 
2484 	iscsit_pdu_tx(reject_pdu);
2485 }
2486 
2487 
2488 static iscsit_task_t *
2489 iscsit_task_alloc(iscsit_conn_t *ict)
2490 {
2491 	iscsit_task_t *itask;
2492 	iscsit_buf_t *immed_ibuf;
2493 
2494 	/*
2495 	 * Possible items to pre-alloc if we cache iscsit_task_t's:
2496 	 *
2497 	 * Status PDU w/ sense buffer
2498 	 * stmf_data_buf_t for immediate data
2499 	 */
2500 	itask = kmem_alloc(sizeof (iscsit_task_t) + sizeof (iscsit_buf_t) +
2501 	    sizeof (stmf_data_buf_t), KM_NOSLEEP);
2502 	if (itask != NULL) {
2503 		mutex_init(&itask->it_mutex, NULL, MUTEX_DRIVER, NULL);
2504 		itask->it_aborted = itask->it_stmf_abort =
2505 		    itask->it_tm_task = 0;
2506 
2507 		immed_ibuf = (iscsit_buf_t *)(itask + 1);
2508 		bzero(immed_ibuf, sizeof (*immed_ibuf));
2509 		immed_ibuf->ibuf_is_immed = B_TRUE;
2510 		immed_ibuf->ibuf_stmf_buf = (stmf_data_buf_t *)(immed_ibuf + 1);
2511 
2512 		bzero(immed_ibuf->ibuf_stmf_buf, sizeof (stmf_data_buf_t));
2513 		immed_ibuf->ibuf_stmf_buf->db_port_private = immed_ibuf;
2514 		immed_ibuf->ibuf_stmf_buf->db_sglist_length = 1;
2515 		immed_ibuf->ibuf_stmf_buf->db_flags = DB_DIRECTION_FROM_RPORT |
2516 		    DB_DONT_CACHE;
2517 		itask->it_immed_data = immed_ibuf;
2518 		itask->it_idm_task = idm_task_alloc(ict->ict_ic);
2519 		if (itask->it_idm_task != NULL) {
2520 			itask->it_idm_task->idt_private = itask;
2521 			itask->it_ict = ict;
2522 			itask->it_ttt = itask->it_idm_task->idt_tt;
2523 			return (itask);
2524 		} else {
2525 			kmem_free(itask, sizeof (iscsit_task_t) +
2526 			    sizeof (iscsit_buf_t) + sizeof (stmf_data_buf_t));
2527 		}
2528 	}
2529 
2530 	return (NULL);
2531 }
2532 
2533 static void
2534 iscsit_task_free(iscsit_task_t *itask)
2535 {
2536 	idm_task_free(itask->it_idm_task);
2537 	mutex_destroy(&itask->it_mutex);
2538 	kmem_free(itask, sizeof (iscsit_task_t) +
2539 	    sizeof (iscsit_buf_t) + sizeof (stmf_data_buf_t));
2540 }
2541 
2542 static iscsit_task_t *
2543 iscsit_tm_task_alloc(iscsit_conn_t *ict)
2544 {
2545 	iscsit_task_t *itask;
2546 
2547 	itask = kmem_zalloc(sizeof (iscsit_task_t), KM_NOSLEEP);
2548 	if (itask != NULL) {
2549 		idm_conn_hold(ict->ict_ic);
2550 		mutex_init(&itask->it_mutex, NULL, MUTEX_DRIVER, NULL);
2551 		itask->it_aborted = itask->it_stmf_abort =
2552 		    itask->it_tm_responded = 0;
2553 		itask->it_tm_pdu = NULL;
2554 		itask->it_tm_task = 1;
2555 		itask->it_ict = ict;
2556 	}
2557 
2558 	return (itask);
2559 }
2560 
2561 static void
2562 iscsit_tm_task_free(iscsit_task_t *itask)
2563 {
2564 	/*
2565 	 * If we responded then the call to idm_pdu_complete will free the
2566 	 * PDU.  Otherwise we got aborted before the TM function could
2567 	 * complete and we need to free the PDU explicitly.
2568 	 */
2569 	if (itask->it_tm_pdu != NULL && !itask->it_tm_responded)
2570 		idm_pdu_free(itask->it_tm_pdu);
2571 	idm_conn_rele(itask->it_ict->ict_ic);
2572 	mutex_destroy(&itask->it_mutex);
2573 	kmem_free(itask, sizeof (iscsit_task_t));
2574 }
2575 
2576 static idm_status_t
2577 iscsit_task_start(iscsit_task_t *itask)
2578 {
2579 	iscsit_sess_t *ist = itask->it_ict->ict_sess;
2580 	avl_index_t		where;
2581 
2582 	/*
2583 	 * Sanity check the ITT and ensure that this task does not already
2584 	 * exist.  If not then add the task to the session task list.
2585 	 */
2586 	mutex_enter(&ist->ist_mutex);
2587 	mutex_enter(&itask->it_mutex);
2588 	itask->it_active = 1;
2589 	if (avl_find(&ist->ist_task_list, itask, &where) == NULL) {
2590 		/* New task, add to AVL */
2591 		avl_insert(&ist->ist_task_list, itask, where);
2592 		mutex_exit(&itask->it_mutex);
2593 		mutex_exit(&ist->ist_mutex);
2594 		return (IDM_STATUS_SUCCESS);
2595 	}
2596 	mutex_exit(&itask->it_mutex);
2597 	mutex_exit(&ist->ist_mutex);
2598 
2599 	return (IDM_STATUS_REJECT);
2600 }
2601 
2602 static void
2603 iscsit_task_done(iscsit_task_t *itask)
2604 {
2605 	iscsit_sess_t *ist = itask->it_ict->ict_sess;
2606 
2607 	mutex_enter(&ist->ist_mutex);
2608 	mutex_enter(&itask->it_mutex);
2609 	if (itask->it_active) {
2610 		avl_remove(&ist->ist_task_list, itask);
2611 		itask->it_active = 0;
2612 	}
2613 	mutex_exit(&itask->it_mutex);
2614 	mutex_exit(&ist->ist_mutex);
2615 }
2616 
2617 /*
2618  * iscsit status PDU cache
2619  */
2620 
2621 /*ARGSUSED*/
2622 static int
2623 iscsit_status_pdu_constructor(void *pdu_void, void *arg, int flags)
2624 {
2625 	idm_pdu_t *pdu = pdu_void;
2626 	iscsi_scsi_rsp_hdr_t *rsp;
2627 
2628 	bzero(pdu, sizeof (idm_pdu_t));
2629 	pdu->isp_callback = iscsit_send_good_status_done;
2630 	pdu->isp_magic = IDM_PDU_MAGIC;
2631 	pdu->isp_hdr = (iscsi_hdr_t *)(pdu + 1); /* Ptr arithmetic */
2632 	pdu->isp_hdrlen = sizeof (iscsi_hdr_t);
2633 
2634 	/* Setup status response */
2635 	rsp = (iscsi_scsi_rsp_hdr_t *)pdu->isp_hdr;
2636 	bzero(rsp, sizeof (*rsp));
2637 	rsp->opcode = ISCSI_OP_SCSI_RSP;
2638 	rsp->flags = ISCSI_FLAG_FINAL;
2639 	rsp->response = ISCSI_STATUS_CMD_COMPLETED;
2640 
2641 	return (0);
2642 }
2643 
2644 /*
2645  * iscsit private data handler
2646  */
2647 
2648 /*ARGSUSED*/
2649 static void
2650 iscsit_pp_cb(struct stmf_port_provider *pp, int cmd, void *arg, uint32_t flags)
2651 {
2652 	it_config_t		*cfg;
2653 	nvlist_t		*nvl;
2654 
2655 	if ((cmd != STMF_PROVIDER_DATA_UPDATED) || (arg == NULL)) {
2656 		return;
2657 	}
2658 
2659 	nvl = (nvlist_t *)arg;
2660 
2661 	/* Translate nvlist */
2662 	if (it_nv_to_config(nvl, &cfg) != 0) {
2663 		cmn_err(CE_WARN, "Configuration is invalid");
2664 		return;
2665 	}
2666 
2667 	/* Update config */
2668 	(void) iscsit_config_merge(cfg);
2669 
2670 	it_config_free_cmn(cfg);
2671 }
2672 
2673 
2674 static it_cfg_status_t
2675 iscsit_config_merge(it_config_t *in_cfg)
2676 {
2677 	it_cfg_status_t	status;
2678 	it_config_t	*cfg;
2679 	it_config_t	tmp_cfg;
2680 	list_t		tpg_del_list;
2681 
2682 	if (in_cfg) {
2683 		cfg = in_cfg;
2684 	} else {
2685 		/* Make empty config */
2686 		bzero(&tmp_cfg, sizeof (tmp_cfg));
2687 		cfg = &tmp_cfg;
2688 	}
2689 
2690 	list_create(&tpg_del_list,  sizeof (iscsit_tpg_t),
2691 	    offsetof(iscsit_tpg_t, tpg_delete_ln));
2692 
2693 	/*
2694 	 * Update targets, initiator contexts, target portal groups,
2695 	 * and iSNS client
2696 	 */
2697 	ISCSIT_GLOBAL_LOCK(RW_WRITER);
2698 	if (((status = iscsit_config_merge_tpg(cfg, &tpg_del_list))
2699 	    != 0) ||
2700 	    ((status = iscsit_config_merge_tgt(cfg)) != 0) ||
2701 	    ((status = iscsit_config_merge_ini(cfg)) != 0) ||
2702 	    ((status = isnst_config_merge(cfg)) != 0)) {
2703 		ISCSIT_GLOBAL_UNLOCK();
2704 		return (status);
2705 	}
2706 
2707 	/* Update other global config parameters */
2708 	if (iscsit_global.global_props) {
2709 		nvlist_free(iscsit_global.global_props);
2710 		iscsit_global.global_props = NULL;
2711 	}
2712 	if (in_cfg) {
2713 		(void) nvlist_dup(cfg->config_global_properties,
2714 		    &iscsit_global.global_props, KM_SLEEP);
2715 	}
2716 	ISCSIT_GLOBAL_UNLOCK();
2717 
2718 	iscsit_config_destroy_tpgs(&tpg_del_list);
2719 
2720 	list_destroy(&tpg_del_list);
2721 
2722 	return (ITCFG_SUCCESS);
2723 }
2724 
2725 /*
2726  * iscsit_sna_lt[e]
2727  *
2728  * Compare serial numbers using serial number arithmetic as defined in
2729  * RFC 1982.
2730  *
2731  * NOTE: This code is duplicated in the isns server as well as iscsitgtd.  It
2732  * ought to be common.
2733  */
2734 
2735 static int
2736 iscsit_sna_lt(uint32_t sn1, uint32_t sn2)
2737 {
2738 	return ((sn1 != sn2) &&
2739 	    (((sn1 < sn2) && ((sn2 - sn1) < ISCSIT_SNA32_CHECK)) ||
2740 	    ((sn1 > sn2) && ((sn1 - sn2) > ISCSIT_SNA32_CHECK))));
2741 }
2742 
2743 static int
2744 iscsit_sna_lte(uint32_t sn1, uint32_t sn2)
2745 {
2746 	return ((sn1 == sn2) ||
2747 	    (((sn1 < sn2) && ((sn2 - sn1) < ISCSIT_SNA32_CHECK)) ||
2748 	    ((sn1 > sn2) && ((sn1 - sn2) > ISCSIT_SNA32_CHECK))));
2749 }
2750 
2751 
2752 static boolean_t
2753 iscsit_cmdsn_in_window(iscsit_conn_t *ict, uint32_t cmdsn)
2754 {
2755 	iscsit_sess_t	*ist = ict->ict_sess;
2756 	int		rval = B_TRUE;
2757 
2758 	ist = ict->ict_sess;
2759 
2760 	rw_enter(&ist->ist_sn_rwlock, RW_READER);
2761 
2762 	/*
2763 	 * If cmdsn is less than ist_expcmdsn - iscsit_cmd_window() or
2764 	 * greater than ist_expcmdsn, it's not in the window.
2765 	 */
2766 
2767 	if (iscsit_sna_lt(cmdsn, (ist->ist_expcmdsn - iscsit_cmd_window())) ||
2768 	    !iscsit_sna_lte(cmdsn, ist->ist_expcmdsn)) {
2769 		rval = B_FALSE;
2770 	}
2771 
2772 	rw_exit(&ist->ist_sn_rwlock);
2773 
2774 	return (rval);
2775 }
2776