xref: /titanic_52/usr/src/uts/common/io/ib/clients/iser/iser_cq.c (revision a82ec3cf2b07d0f2ebb2e60f41370b7c39a5e71e)
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/types.h>
27 #include <sys/ddi.h>
28 #include <sys/types.h>
29 #include <sys/socket.h>
30 #include <netinet/in.h>
31 #include <sys/sunddi.h>
32 #include <sys/sdt.h>
33 #include <sys/ib/ibtl/ibti.h>
34 #include <sys/ib/ibtl/ibtl_types.h>
35 
36 #include <sys/ib/clients/iser/iser.h>
37 
38 /*
39  * iser_cq.c
40  *    Routines for completion queue handlers for iSER.
41  */
42 static void iser_msg_handle(iser_chan_t *chan, iser_msg_t *msg);
43 int iser_iscsihdr_handle(iser_chan_t *chan, iser_msg_t *msg);
44 static int iser_ib_poll_send_completions(ibt_cq_hdl_t cq_hdl,
45     iser_chan_t *iser_chan);
46 static int iser_ib_poll_recv_completions(ibt_cq_hdl_t cq_hdl,
47     iser_chan_t *iser_chan);
48 
49 void
50 iser_ib_sendcq_handler(ibt_cq_hdl_t cq_hdl, void *arg)
51 {
52 	iser_chan_t	*iser_chan;
53 	ibt_status_t	status;
54 
55 	iser_chan = (iser_chan_t *)arg;
56 
57 	/*
58 	 * Poll for work request completion while successful. If the
59 	 * queue empties or otherwise becomes invalid, stop polling.
60 	 */
61 	do {
62 		status = iser_ib_poll_send_completions(cq_hdl, iser_chan);
63 	} while (status == IBT_SUCCESS);
64 
65 	if (status == IBT_CQ_EMPTY) {
66 		/* We've emptied the CQ, rearm it before we're done here */
67 		status = ibt_enable_cq_notify(cq_hdl, IBT_NEXT_COMPLETION);
68 		if (status != IBT_SUCCESS) {
69 			/* Unexpected error */
70 			ISER_LOG(CE_NOTE, "iser_ib_sendcq_handler: "
71 			    "ibt_enable_cq_notify error (%d)", status);
72 			return;
73 		}
74 
75 		/* Now, check for more completions after the rearm */
76 		do {
77 			status = iser_ib_poll_send_completions(
78 			    cq_hdl, iser_chan);
79 		} while (status == IBT_SUCCESS);
80 	}
81 }
82 
83 static int
84 iser_ib_poll_send_completions(ibt_cq_hdl_t cq_hdl, iser_chan_t *iser_chan)
85 {
86 	ibt_wc_t	wc[ISER_IB_SCQ_POLL_MAX];
87 	ibt_wrid_t	wrid;
88 	idm_buf_t	*idb = NULL;
89 	idm_task_t	*idt = NULL;
90 	iser_wr_t	*wr = NULL;
91 	int		i;
92 	uint_t		npoll = 0;
93 	ibt_status_t	status;
94 	iser_conn_t	*iser_conn;
95 	idm_status_t	idm_status;
96 	iser_mr_t	*mr;
97 
98 	iser_conn = iser_chan->ic_conn;
99 
100 	/* Poll ISER_IB_SCQ_POLL_MAX completions from the CQ */
101 	status = ibt_poll_cq(cq_hdl, wc, ISER_IB_SCQ_POLL_MAX, &npoll);
102 
103 	if (status != IBT_SUCCESS) {
104 		if (status != IBT_CQ_EMPTY) {
105 			/* Unexpected error */
106 			ISER_LOG(CE_NOTE, "iser_ib_sendcq_handler: ibt_poll_cq "
107 			    "unexpected error (%d)", status);
108 		}
109 		/* CQ is empty. Either way, move along... */
110 		return (status);
111 	}
112 
113 	/*
114 	 * Handle each of the completions we've polled
115 	 */
116 	for (i = 0; i < npoll; i++) {
117 
118 		DTRACE_PROBE3(iser__send__cqe, iser_chan_t *, iser_chan,
119 		    ibt_wc_t *, &wc[i], ibt_wc_status_t, wc[i].wc_status);
120 
121 		/* Grab the wrid of the completion */
122 		wrid = wc[i].wc_id;
123 
124 		/* Decrement this channel's SQ posted count */
125 		mutex_enter(&iser_chan->ic_sq_post_lock);
126 		iser_chan->ic_sq_post_count--;
127 		mutex_exit(&iser_chan->ic_sq_post_lock);
128 
129 		/* Pull in the wr handle */
130 		wr = (iser_wr_t *)(uintptr_t)wrid;
131 		ASSERT(wr != NULL);
132 
133 		/* Set an idm_status for return to IDM */
134 		idm_status = (wc[i].wc_status == IBT_WC_SUCCESS) ?
135 		    IDM_STATUS_SUCCESS : IDM_STATUS_FAIL;
136 
137 		/*
138 		 * A non-success status here indicates the QP went
139 		 * into an error state while this WR was being
140 		 * processed. This can also happen when the
141 		 * channel is closed on the remote end. Clean up
142 		 * the resources, then push CE_TRANSPORT_FAIL
143 		 * into IDM.
144 		 */
145 		if (wc[i].wc_status != IBT_WC_SUCCESS) {
146 			/*
147 			 * Free the resources attached to this
148 			 * completion.
149 			 */
150 			if (wr->iw_msg != NULL) {
151 				/* Free iser_msg handle */
152 				iser_msg_free(wr->iw_msg);
153 			}
154 
155 			if (wr->iw_pdu != NULL) {
156 				/* Complete the PDU */
157 				idm_pdu_complete(wr->iw_pdu, idm_status);
158 			}
159 
160 			if (wr->iw_buf != NULL) {
161 				/* Invoke buffer callback */
162 				idb = wr->iw_buf;
163 				mr = ((iser_buf_t *)
164 				    idb->idb_buf_private)->iser_mr;
165 #ifdef DEBUG
166 				bcopy(&wc[i],
167 				    &((iser_buf_t *)idb->idb_buf_private)->
168 				    buf_wc, sizeof (ibt_wc_t));
169 #endif
170 				idt = idb->idb_task_binding;
171 				mutex_enter(&idt->idt_mutex);
172 				if (wr->iw_type == ISER_WR_RDMAW) {
173 					DTRACE_ISCSI_8(xfer__done,
174 					    idm_conn_t *, idt->idt_ic,
175 					    uintptr_t, idb->idb_buf,
176 					    uint32_t, idb->idb_bufoffset,
177 					    uint64_t, mr->is_mrva, uint32_t, 0,
178 					    uint32_t, mr->is_mrrkey,
179 					    uint32_t, idb->idb_xfer_len,
180 					    int, XFER_BUF_TX_TO_INI);
181 					idm_buf_tx_to_ini_done(idt, idb,
182 					    IDM_STATUS_FAIL);
183 				} else { /* ISER_WR_RDMAR */
184 					DTRACE_ISCSI_8(xfer__done,
185 					    idm_conn_t *, idt->idt_ic,
186 					    uintptr_t, idb->idb_buf,
187 					    uint32_t, idb->idb_bufoffset,
188 					    uint64_t, mr->is_mrva, uint32_t, 0,
189 					    uint32_t, mr->is_mrrkey,
190 					    uint32_t, idb->idb_xfer_len,
191 					    int, XFER_BUF_RX_FROM_INI);
192 					idm_buf_rx_from_ini_done(idt, idb,
193 					    IDM_STATUS_FAIL);
194 				}
195 			}
196 
197 			/* Free the iser wr handle */
198 			iser_wr_free(wr);
199 
200 			/*
201 			 * Tell IDM that the channel has gone down,
202 			 * unless he already knows.
203 			 */
204 			mutex_enter(&iser_conn->ic_lock);
205 			switch (iser_conn->ic_stage) {
206 			case ISER_CONN_STAGE_IC_DISCONNECTED:
207 			case ISER_CONN_STAGE_IC_FREED:
208 			case ISER_CONN_STAGE_CLOSING:
209 			case ISER_CONN_STAGE_CLOSED:
210 				break;
211 
212 			default:
213 				idm_conn_event(iser_conn->ic_idmc,
214 				    CE_TRANSPORT_FAIL, idm_status);
215 				iser_conn->ic_stage = ISER_CONN_STAGE_CLOSING;
216 			}
217 			mutex_exit(&iser_conn->ic_lock);
218 
219 			/* Move onto the next completion */
220 			continue;
221 		}
222 
223 		/*
224 		 * For a success status, just invoke the PDU or
225 		 * buffer completion. We use our WR handle's
226 		 * "iw_type" here so that we can properly process
227 		 * because the CQE's opcode is invalid if the status
228 		 * is failed.
229 		 */
230 		switch (wr->iw_type) {
231 		case ISER_WR_SEND:
232 			/* Free the msg handle */
233 			ASSERT(wr->iw_msg != NULL);
234 			iser_msg_free(wr->iw_msg);
235 
236 			if (wr->iw_pdu == NULL) {
237 				/* This is a hello exchange message */
238 				mutex_enter(&iser_conn->ic_lock);
239 				if (iser_conn->ic_stage ==
240 				    ISER_CONN_STAGE_HELLOREPLY_SENT) {
241 					/*
242 					 * We're on the target side,
243 					 * and have just successfully
244 					 * sent the HelloReply msg.
245 					 */
246 					iser_conn->ic_stage =
247 					    ISER_CONN_STAGE_LOGGED_IN;
248 				}
249 				mutex_exit(&iser_conn->ic_lock);
250 			} else {
251 				/* This is a normal control message */
252 				idm_pdu_complete(wr->iw_pdu, idm_status);
253 			}
254 
255 			/* Free the wr handle */
256 			iser_wr_free(wr);
257 
258 			break;
259 
260 		case ISER_WR_RDMAW:
261 		case ISER_WR_RDMAR:
262 			/*
263 			 * Invoke the appropriate callback;
264 			 * the buffer will be freed there.
265 			 */
266 			idb = wr->iw_buf;
267 			mr = ((iser_buf_t *)idb->idb_buf_private)->iser_mr;
268 #ifdef DEBUG
269 			bcopy(&wc[i],
270 			    &((iser_buf_t *)idb->idb_buf_private)->buf_wc,
271 			    sizeof (ibt_wc_t));
272 #endif
273 			idt = idb->idb_task_binding;
274 
275 			mutex_enter(&idt->idt_mutex);
276 			if (wr->iw_type == ISER_WR_RDMAW) {
277 				DTRACE_ISCSI_8(xfer__done,
278 				    idm_conn_t *, idt->idt_ic,
279 				    uintptr_t, idb->idb_buf,
280 				    uint32_t, idb->idb_bufoffset,
281 				    uint64_t, mr->is_mrva, uint32_t, 0,
282 				    uint32_t, mr->is_mrrkey,
283 				    uint32_t, idb->idb_xfer_len,
284 				    int, XFER_BUF_TX_TO_INI);
285 				idm_buf_tx_to_ini_done(idt, idb, idm_status);
286 			} else {
287 				DTRACE_ISCSI_8(xfer__done,
288 				    idm_conn_t *, idt->idt_ic,
289 				    uintptr_t, idb->idb_buf,
290 				    uint32_t, idb->idb_bufoffset,
291 				    uint64_t, mr->is_mrva, uint32_t, 0,
292 				    uint32_t, mr->is_mrrkey,
293 				    uint32_t, idb->idb_xfer_len,
294 				    int, XFER_BUF_RX_FROM_INI);
295 				idm_buf_rx_from_ini_done(idt, idb, idm_status);
296 			}
297 
298 			/* Free the wr handle */
299 			iser_wr_free(wr);
300 
301 			break;
302 
303 		default:
304 			ASSERT(0);
305 			break;
306 		}
307 	}
308 
309 	return (status);
310 }
311 
312 void
313 iser_ib_recvcq_handler(ibt_cq_hdl_t cq_hdl, void *arg)
314 {
315 	iser_chan_t	*iser_chan;
316 	ibt_status_t	status;
317 
318 	iser_chan = (iser_chan_t *)arg;
319 
320 	/*
321 	 * Poll for work request completion while successful. If the
322 	 * queue empties or otherwise becomes invalid, stop polling.
323 	 */
324 	do {
325 		status = iser_ib_poll_recv_completions(cq_hdl, iser_chan);
326 	} while (status == IBT_SUCCESS);
327 
328 	if (status == IBT_CQ_EMPTY) {
329 		/* We've emptied the CQ, rearm it before we're done here */
330 		status = ibt_enable_cq_notify(cq_hdl, IBT_NEXT_COMPLETION);
331 		if (status != IBT_SUCCESS) {
332 			/* Unexpected error */
333 			ISER_LOG(CE_NOTE, "iser_ib_recvcq_handler: "
334 			    "ibt_enable_cq_notify error (%d)", status);
335 			return;
336 		}
337 
338 		/* Now, check for more completions after the rearm */
339 		do {
340 			status = iser_ib_poll_recv_completions(
341 			    cq_hdl, iser_chan);
342 		} while (status == IBT_SUCCESS);
343 	}
344 }
345 
346 static int
347 iser_ib_poll_recv_completions(ibt_cq_hdl_t cq_hdl, iser_chan_t *iser_chan)
348 {
349 	ibt_wc_t	wc;
350 	iser_msg_t	*msg;
351 	iser_qp_t	*iser_qp;
352 	int		status;
353 
354 	iser_qp = &(iser_chan->ic_qp);
355 
356 	bzero(&wc, sizeof (ibt_wc_t));
357 	status = ibt_poll_cq(cq_hdl, &wc, 1, NULL);
358 	if (status == IBT_CQ_EMPTY) {
359 		/* CQ is empty, return */
360 		return (status);
361 	}
362 
363 	if (status != IBT_SUCCESS) {
364 		/* Unexpected error */
365 		ISER_LOG(CE_NOTE, "iser_ib_poll_recv_completions: "
366 		    "ibt_poll_cq error (%d)", status);
367 		mutex_enter(&iser_qp->qp_lock);
368 		iser_qp->rq_level--;
369 		mutex_exit(&iser_qp->qp_lock);
370 		/* Free the msg handle (if we got it back) */
371 		if ((msg = (iser_msg_t *)(uintptr_t)wc.wc_id) != NULL) {
372 			iser_msg_free(msg);
373 		}
374 		return (status);
375 	}
376 
377 	/* Retrieve the iSER msg handle */
378 	msg = (iser_msg_t *)(uintptr_t)wc.wc_id;
379 	ASSERT(msg != NULL);
380 
381 	/*
382 	 * Decrement the posted level in the RQ, then check
383 	 * to see if we need to fill the RQ back up (or if
384 	 * we are already on the taskq).
385 	 */
386 	mutex_enter(&iser_chan->ic_conn->ic_lock);
387 	mutex_enter(&iser_qp->qp_lock);
388 	iser_qp->rq_level--;
389 
390 	if ((iser_qp->rq_taskqpending == B_FALSE) &&
391 	    (iser_qp->rq_level <= iser_qp->rq_lwm) &&
392 	    (iser_chan->ic_conn->ic_stage >= ISER_CONN_STAGE_IC_CONNECTED) &&
393 	    (iser_chan->ic_conn->ic_stage <= ISER_CONN_STAGE_LOGGED_IN)) {
394 		/* Set the pending flag and fire off a post_recv */
395 		iser_qp->rq_taskqpending = B_TRUE;
396 		mutex_exit(&iser_qp->qp_lock);
397 
398 		status = iser_ib_post_recv_async(iser_chan->ic_chanhdl);
399 
400 		if (status != DDI_SUCCESS) {
401 			ISER_LOG(CE_NOTE, "iser_ib_poll_recv_completions: "
402 			    "task dispatch failed");
403 			/* Failure to launch, unset the pending flag */
404 			mutex_enter(&iser_qp->qp_lock);
405 			iser_qp->rq_taskqpending = B_FALSE;
406 			mutex_exit(&iser_qp->qp_lock);
407 		}
408 	} else {
409 		mutex_exit(&iser_qp->qp_lock);
410 	}
411 
412 	DTRACE_PROBE3(iser__recv__cqe, iser_chan_t *, iser_chan,
413 	    ibt_wc_t *, &wc, ibt_wc_status_t, wc.wc_status);
414 	if (wc.wc_status != IBT_WC_SUCCESS) {
415 		/*
416 		 * Tell IDM that the channel has gone down,
417 		 * unless he already knows.
418 		 */
419 		switch (iser_chan->ic_conn->ic_stage) {
420 		case ISER_CONN_STAGE_IC_DISCONNECTED:
421 		case ISER_CONN_STAGE_IC_FREED:
422 		case ISER_CONN_STAGE_CLOSING:
423 		case ISER_CONN_STAGE_CLOSED:
424 			break;
425 
426 		default:
427 			idm_conn_event(iser_chan->ic_conn->ic_idmc,
428 			    CE_TRANSPORT_FAIL, IDM_STATUS_FAIL);
429 			iser_chan->ic_conn->ic_stage =
430 			    ISER_CONN_STAGE_CLOSING;
431 		}
432 		mutex_exit(&iser_chan->ic_conn->ic_lock);
433 
434 		iser_msg_free(msg);
435 		return (DDI_SUCCESS);
436 	} else {
437 		mutex_exit(&iser_chan->ic_conn->ic_lock);
438 
439 		/*
440 		 * We have an iSER message in, let's handle it.
441 		 * We will free the iser_msg_t later in this path,
442 		 * depending upon the action required.
443 		 */
444 		iser_msg_handle(iser_chan, msg);
445 		return (DDI_SUCCESS);
446 	}
447 }
448 
449 static void
450 iser_msg_handle(iser_chan_t *chan, iser_msg_t *msg)
451 {
452 	int		opcode;
453 	iser_ctrl_hdr_t	*hdr = NULL;
454 	iser_conn_t	*iser_conn = chan->ic_conn;
455 	int		status;
456 
457 	hdr = (iser_ctrl_hdr_t *)(uintptr_t)msg->msg_ds.ds_va;
458 	ASSERT(hdr != NULL);
459 
460 	opcode = hdr->opcode;
461 	if (opcode == ISER_OPCODE_CTRL_TYPE_PDU) {
462 		/*
463 		 * Handle an iSCSI Control PDU iSER message.
464 		 * Note we'll free the msg handle in the PDU callback.
465 		 */
466 		status = iser_iscsihdr_handle(chan, msg);
467 		if (status != DDI_SUCCESS) {
468 			/*
469 			 * We are unable to handle this message, and
470 			 * have no way to recover from this.  Fail the
471 			 * transport.
472 			 */
473 			ISER_LOG(CE_NOTE, "iser_msg_handle: failed "
474 			    "iser_iscsihdr_handle");
475 			iser_msg_free(msg);
476 			idm_conn_event(iser_conn->ic_idmc,
477 			    CE_TRANSPORT_FAIL, IDM_STATUS_FAIL);
478 		}
479 	} else if (opcode == ISER_OPCODE_HELLO_MSG) { /* at the target */
480 		/*
481 		 * We are currently not supporting Hello Exchange,
482 		 * since OFED iSER does not. May be revisited.
483 		 */
484 		ASSERT(opcode != ISER_OPCODE_HELLO_MSG);
485 
486 		if (iser_conn->ic_type != ISER_CONN_TYPE_TGT) {
487 			idm_conn_event(iser_conn->ic_idmc,
488 			    CE_TRANSPORT_FAIL, IDM_STATUS_FAIL);
489 		}
490 
491 		iser_hello_hdr_t *hello_hdr = (iser_hello_hdr_t *)hdr;
492 
493 		ISER_LOG(CE_NOTE, "received Hello message: opcode[%d], "
494 		    "maxver[%d], minver[%d], iser_ird[%d], msg (0x%p)",
495 		    hello_hdr->opcode, hello_hdr->maxver, hello_hdr->minver,
496 		    ntohs(hello_hdr->iser_ird), (void *)msg);
497 
498 		mutex_enter(&iser_conn->ic_lock);
499 
500 		if (iser_conn->ic_stage != ISER_CONN_STAGE_HELLO_WAIT) {
501 			/* target is not expected to receive a Hello */
502 			idm_conn_event(iser_conn->ic_idmc,
503 			    CE_TRANSPORT_FAIL, IDM_STATUS_FAIL);
504 		}
505 
506 		iser_conn->ic_stage = ISER_CONN_STAGE_HELLOREPLY_SENT;
507 		mutex_exit(&iser_conn->ic_lock);
508 
509 		/* Prepare and send a HelloReply message */
510 		status = iser_xfer_helloreply_msg(chan);
511 		if (status != ISER_STATUS_SUCCESS) {
512 
513 			mutex_enter(&iser_conn->ic_lock);
514 			iser_conn->ic_stage =
515 			    ISER_CONN_STAGE_HELLOREPLY_SENT_FAIL;
516 			mutex_exit(&iser_conn->ic_lock);
517 
518 			idm_conn_event(iser_conn->ic_idmc,
519 			    CE_TRANSPORT_FAIL, status);
520 		}
521 
522 		/* Free this msg handle */
523 		iser_msg_free(msg);
524 
525 	} else if (opcode == ISER_OPCODE_HELLOREPLY_MSG) { /* at initiator */
526 
527 		/*
528 		 * We are currently not supporting Hello Exchange,
529 		 * since OFED iSER does not. May be revisited.
530 		 */
531 		ASSERT(opcode != ISER_OPCODE_HELLOREPLY_MSG);
532 
533 		if (iser_conn->ic_type != ISER_CONN_TYPE_INI) {
534 			idm_conn_event(iser_conn->ic_idmc,
535 			    CE_TRANSPORT_FAIL, status);
536 		}
537 
538 		iser_helloreply_hdr_t *hello_hdr = (iser_helloreply_hdr_t *)hdr;
539 
540 		ISER_LOG(CE_NOTE, "received Hello Reply message: opcode[%d], "
541 		    "maxver[%d], curver[%d], iser_ord[%d], msg (0x%p)",
542 		    hello_hdr->opcode, hello_hdr->maxver, hello_hdr->curver,
543 		    ntohs(hello_hdr->iser_ord), (void *)msg);
544 
545 		/* Free this msg handle */
546 		iser_msg_free(msg);
547 
548 		/*
549 		 * Signal the receipt of HelloReply to the waiting thread
550 		 * so that the initiator can proceed to the Full Feature
551 		 * Phase.
552 		 */
553 		mutex_enter(&iser_conn->ic_lock);
554 		iser_conn->ic_stage = ISER_CONN_STAGE_HELLOREPLY_RCV;
555 		cv_signal(&iser_conn->ic_stage_cv);
556 		mutex_exit(&iser_conn->ic_lock);
557 	} else {
558 		/* Protocol error: free the msg handle and fail the session */
559 		ISER_LOG(CE_NOTE, "iser_msg_handle: unsupported opcode (0x%x): "
560 		    "terminating session on IDM handle (0x%p)", opcode,
561 		    (void *) iser_conn->ic_idmc);
562 
563 		iser_msg_free(msg);
564 		idm_conn_event(iser_conn->ic_idmc, CE_TRANSPORT_FAIL,
565 		    IDM_STATUS_FAIL);
566 	}
567 }
568 
569 #define	IDM_PDU_OPCODE(PDU) \
570 	((PDU)->isp_hdr->opcode & ISCSI_OPCODE_MASK)
571 
572 /* network to host translation for 24b integers */
573 static uint32_t
574 n2h24(uchar_t *ptr)
575 {
576 	return ((ptr[0] << 16) | (ptr[1] << 8) | ptr[2]);
577 }
578 
579 /* ARGSUSED */
580 static void
581 iser_rx_pdu_cb(idm_pdu_t *pdu, idm_status_t status)
582 {
583 	/* Free the iser msg handle and the PDU handle */
584 	iser_msg_free((iser_msg_t *)pdu->isp_transport_private);
585 	idm_pdu_free(pdu);
586 }
587 
588 int
589 iser_iscsihdr_handle(iser_chan_t *chan, iser_msg_t *msg)
590 {
591 	idm_pdu_t	*pdu;
592 	uint8_t		*iser_hdrp;
593 	uint8_t		*iscsi_hdrp;
594 	iscsi_hdr_t	*bhs;
595 
596 	pdu = idm_pdu_alloc_nosleep(sizeof (iscsi_hdr_t), 0);
597 	pdu->isp_ic = chan->ic_conn->ic_idmc;
598 	ASSERT(pdu->isp_ic != NULL);
599 
600 	/* Set the iser_msg handle into the transport-private field */
601 	pdu->isp_transport_private = (void *)msg;
602 
603 	/* Set up a pointer in the pdu handle to the iSER header */
604 	iser_hdrp = (uint8_t *)(uintptr_t)msg->msg_ds.ds_va;
605 	if (iser_hdrp == NULL) {
606 		ISER_LOG(CE_NOTE, "iser_iscsihdr_handle: iser_hdrp is NULL");
607 		idm_pdu_free(pdu);
608 		return (ISER_STATUS_FAIL);
609 	}
610 	pdu->isp_transport_hdr = (void *)iser_hdrp;
611 	pdu->isp_transport_hdrlen = ISER_HEADER_LENGTH;
612 
613 	/*
614 	 * Set up a pointer to the iSCSI header, which is directly
615 	 * after the iSER header in the message.
616 	 */
617 	iscsi_hdrp = ((uint8_t *)(uintptr_t)msg->msg_ds.ds_va) +
618 	    ISER_HEADER_LENGTH;
619 	if (iscsi_hdrp == NULL) {
620 		ISER_LOG(CE_NOTE, "iser_iscsihdr_handle: iscsi_hdrp is NULL");
621 		idm_pdu_free(pdu);
622 		return (ISER_STATUS_FAIL);
623 	}
624 	pdu->isp_hdr = (iscsi_hdr_t *)(uintptr_t)iscsi_hdrp;
625 
626 	/* Fill in the BHS */
627 	bhs = pdu->isp_hdr;
628 	pdu->isp_hdrlen	= sizeof (iscsi_hdr_t) +
629 	    (bhs->hlength * sizeof (uint32_t));
630 	pdu->isp_datalen = n2h24(bhs->dlength);
631 	pdu->isp_callback = iser_rx_pdu_cb;
632 
633 	/*
634 	 * If datalen > 0, then non-scsi data may be present. Allocate
635 	 * space in the PDU handle and set a pointer to the data.
636 	 */
637 	if (pdu->isp_datalen) {
638 		pdu->isp_data = ((uint8_t *)(uintptr_t)pdu->isp_hdr) +
639 		    pdu->isp_hdrlen;
640 	}
641 
642 	/* Process RX PDU */
643 	idm_pdu_rx(pdu->isp_ic, pdu);
644 
645 	return (DDI_SUCCESS);
646 }
647