1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * This file contains iSCSI extentions for RDMA (iSER) Verbs
4  *
5  * (c) Copyright 2013 Datera, Inc.
6  *
7  * Nicholas A. Bellinger <nab@linux-iscsi.org>
8  *
9  ****************************************************************************/
10 
11 #include <linux/string.h>
12 #include <linux/module.h>
13 #include <linux/scatterlist.h>
14 #include <linux/socket.h>
15 #include <linux/in.h>
16 #include <linux/in6.h>
17 #include <rdma/ib_verbs.h>
18 #include <rdma/ib_cm.h>
19 #include <rdma/rdma_cm.h>
20 #include <target/target_core_base.h>
21 #include <target/target_core_fabric.h>
22 #include <target/iscsi/iscsi_transport.h>
23 #include <linux/semaphore.h>
24 
25 #include "ib_isert.h"
26 
27 static int isert_debug_level;
28 module_param_named(debug_level, isert_debug_level, int, 0644);
29 MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:0)");
30 
31 static DEFINE_MUTEX(device_list_mutex);
32 static LIST_HEAD(device_list);
33 static struct workqueue_struct *isert_comp_wq;
34 static struct workqueue_struct *isert_release_wq;
35 
36 static int
37 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd);
38 static int
39 isert_login_post_recv(struct isert_conn *isert_conn);
40 static int
41 isert_rdma_accept(struct isert_conn *isert_conn);
42 struct rdma_cm_id *isert_setup_id(struct isert_np *isert_np);
43 
44 static void isert_release_work(struct work_struct *work);
45 static void isert_recv_done(struct ib_cq *cq, struct ib_wc *wc);
46 static void isert_send_done(struct ib_cq *cq, struct ib_wc *wc);
47 static void isert_login_recv_done(struct ib_cq *cq, struct ib_wc *wc);
48 static void isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc);
49 
50 static inline bool
51 isert_prot_cmd(struct isert_conn *conn, struct se_cmd *cmd)
52 {
53 	return (conn->pi_support &&
54 		cmd->prot_op != TARGET_PROT_NORMAL);
55 }
56 
57 
58 static void
59 isert_qp_event_callback(struct ib_event *e, void *context)
60 {
61 	struct isert_conn *isert_conn = context;
62 
63 	isert_err("%s (%d): conn %p\n",
64 		  ib_event_msg(e->event), e->event, isert_conn);
65 
66 	switch (e->event) {
67 	case IB_EVENT_COMM_EST:
68 		rdma_notify(isert_conn->cm_id, IB_EVENT_COMM_EST);
69 		break;
70 	case IB_EVENT_QP_LAST_WQE_REACHED:
71 		isert_warn("Reached TX IB_EVENT_QP_LAST_WQE_REACHED\n");
72 		break;
73 	default:
74 		break;
75 	}
76 }
77 
78 static struct ib_qp *
79 isert_create_qp(struct isert_conn *isert_conn,
80 		struct rdma_cm_id *cma_id)
81 {
82 	u32 cq_size = ISERT_QP_MAX_REQ_DTOS + ISERT_QP_MAX_RECV_DTOS + 2;
83 	struct isert_device *device = isert_conn->device;
84 	struct ib_device *ib_dev = device->ib_device;
85 	struct ib_qp_init_attr attr;
86 	int ret, factor;
87 
88 	isert_conn->cq = ib_cq_pool_get(ib_dev, cq_size, -1, IB_POLL_WORKQUEUE);
89 	if (IS_ERR(isert_conn->cq)) {
90 		isert_err("Unable to allocate cq\n");
91 		ret = PTR_ERR(isert_conn->cq);
92 		return ERR_PTR(ret);
93 	}
94 	isert_conn->cq_size = cq_size;
95 
96 	memset(&attr, 0, sizeof(struct ib_qp_init_attr));
97 	attr.event_handler = isert_qp_event_callback;
98 	attr.qp_context = isert_conn;
99 	attr.send_cq = isert_conn->cq;
100 	attr.recv_cq = isert_conn->cq;
101 	attr.cap.max_send_wr = ISERT_QP_MAX_REQ_DTOS + 1;
102 	attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS + 1;
103 	factor = rdma_rw_mr_factor(device->ib_device, cma_id->port_num,
104 				   ISCSI_ISER_MAX_SG_TABLESIZE);
105 	attr.cap.max_rdma_ctxs = ISCSI_DEF_XMIT_CMDS_MAX * factor;
106 	attr.cap.max_send_sge = device->ib_device->attrs.max_send_sge;
107 	attr.cap.max_recv_sge = 1;
108 	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
109 	attr.qp_type = IB_QPT_RC;
110 	if (device->pi_capable)
111 		attr.create_flags |= IB_QP_CREATE_INTEGRITY_EN;
112 
113 	ret = rdma_create_qp(cma_id, device->pd, &attr);
114 	if (ret) {
115 		isert_err("rdma_create_qp failed for cma_id %d\n", ret);
116 		ib_cq_pool_put(isert_conn->cq, isert_conn->cq_size);
117 
118 		return ERR_PTR(ret);
119 	}
120 
121 	return cma_id->qp;
122 }
123 
124 static int
125 isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
126 {
127 	struct isert_device *device = isert_conn->device;
128 	struct ib_device *ib_dev = device->ib_device;
129 	struct iser_rx_desc *rx_desc;
130 	struct ib_sge *rx_sg;
131 	u64 dma_addr;
132 	int i, j;
133 
134 	isert_conn->rx_descs = kcalloc(ISERT_QP_MAX_RECV_DTOS,
135 				       sizeof(struct iser_rx_desc),
136 				       GFP_KERNEL);
137 	if (!isert_conn->rx_descs)
138 		return -ENOMEM;
139 
140 	rx_desc = isert_conn->rx_descs;
141 
142 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
143 		dma_addr = ib_dma_map_single(ib_dev, (void *)rx_desc,
144 					ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
145 		if (ib_dma_mapping_error(ib_dev, dma_addr))
146 			goto dma_map_fail;
147 
148 		rx_desc->dma_addr = dma_addr;
149 
150 		rx_sg = &rx_desc->rx_sg;
151 		rx_sg->addr = rx_desc->dma_addr;
152 		rx_sg->length = ISER_RX_PAYLOAD_SIZE;
153 		rx_sg->lkey = device->pd->local_dma_lkey;
154 		rx_desc->rx_cqe.done = isert_recv_done;
155 	}
156 
157 	return 0;
158 
159 dma_map_fail:
160 	rx_desc = isert_conn->rx_descs;
161 	for (j = 0; j < i; j++, rx_desc++) {
162 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
163 				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
164 	}
165 	kfree(isert_conn->rx_descs);
166 	isert_conn->rx_descs = NULL;
167 	isert_err("conn %p failed to allocate rx descriptors\n", isert_conn);
168 	return -ENOMEM;
169 }
170 
171 static void
172 isert_free_rx_descriptors(struct isert_conn *isert_conn)
173 {
174 	struct ib_device *ib_dev = isert_conn->device->ib_device;
175 	struct iser_rx_desc *rx_desc;
176 	int i;
177 
178 	if (!isert_conn->rx_descs)
179 		return;
180 
181 	rx_desc = isert_conn->rx_descs;
182 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
183 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
184 				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
185 	}
186 
187 	kfree(isert_conn->rx_descs);
188 	isert_conn->rx_descs = NULL;
189 }
190 
191 static int
192 isert_create_device_ib_res(struct isert_device *device)
193 {
194 	struct ib_device *ib_dev = device->ib_device;
195 	int ret;
196 
197 	isert_dbg("devattr->max_send_sge: %d devattr->max_recv_sge %d\n",
198 		  ib_dev->attrs.max_send_sge, ib_dev->attrs.max_recv_sge);
199 	isert_dbg("devattr->max_sge_rd: %d\n", ib_dev->attrs.max_sge_rd);
200 
201 	device->pd = ib_alloc_pd(ib_dev, 0);
202 	if (IS_ERR(device->pd)) {
203 		ret = PTR_ERR(device->pd);
204 		isert_err("failed to allocate pd, device %p, ret=%d\n",
205 			  device, ret);
206 		return ret;
207 	}
208 
209 	/* Check signature cap */
210 	device->pi_capable = ib_dev->attrs.device_cap_flags &
211 			     IB_DEVICE_INTEGRITY_HANDOVER ? true : false;
212 
213 	return 0;
214 }
215 
216 static void
217 isert_free_device_ib_res(struct isert_device *device)
218 {
219 	isert_info("device %p\n", device);
220 
221 	ib_dealloc_pd(device->pd);
222 }
223 
224 static void
225 isert_device_put(struct isert_device *device)
226 {
227 	mutex_lock(&device_list_mutex);
228 	device->refcount--;
229 	isert_info("device %p refcount %d\n", device, device->refcount);
230 	if (!device->refcount) {
231 		isert_free_device_ib_res(device);
232 		list_del(&device->dev_node);
233 		kfree(device);
234 	}
235 	mutex_unlock(&device_list_mutex);
236 }
237 
238 static struct isert_device *
239 isert_device_get(struct rdma_cm_id *cma_id)
240 {
241 	struct isert_device *device;
242 	int ret;
243 
244 	mutex_lock(&device_list_mutex);
245 	list_for_each_entry(device, &device_list, dev_node) {
246 		if (device->ib_device->node_guid == cma_id->device->node_guid) {
247 			device->refcount++;
248 			isert_info("Found iser device %p refcount %d\n",
249 				   device, device->refcount);
250 			mutex_unlock(&device_list_mutex);
251 			return device;
252 		}
253 	}
254 
255 	device = kzalloc(sizeof(struct isert_device), GFP_KERNEL);
256 	if (!device) {
257 		mutex_unlock(&device_list_mutex);
258 		return ERR_PTR(-ENOMEM);
259 	}
260 
261 	INIT_LIST_HEAD(&device->dev_node);
262 
263 	device->ib_device = cma_id->device;
264 	ret = isert_create_device_ib_res(device);
265 	if (ret) {
266 		kfree(device);
267 		mutex_unlock(&device_list_mutex);
268 		return ERR_PTR(ret);
269 	}
270 
271 	device->refcount++;
272 	list_add_tail(&device->dev_node, &device_list);
273 	isert_info("Created a new iser device %p refcount %d\n",
274 		   device, device->refcount);
275 	mutex_unlock(&device_list_mutex);
276 
277 	return device;
278 }
279 
280 static void
281 isert_init_conn(struct isert_conn *isert_conn)
282 {
283 	isert_conn->state = ISER_CONN_INIT;
284 	INIT_LIST_HEAD(&isert_conn->node);
285 	init_completion(&isert_conn->login_comp);
286 	init_completion(&isert_conn->login_req_comp);
287 	init_waitqueue_head(&isert_conn->rem_wait);
288 	kref_init(&isert_conn->kref);
289 	mutex_init(&isert_conn->mutex);
290 	INIT_WORK(&isert_conn->release_work, isert_release_work);
291 }
292 
293 static void
294 isert_free_login_buf(struct isert_conn *isert_conn)
295 {
296 	struct ib_device *ib_dev = isert_conn->device->ib_device;
297 
298 	ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
299 			    ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
300 	kfree(isert_conn->login_rsp_buf);
301 
302 	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
303 			    ISER_RX_PAYLOAD_SIZE,
304 			    DMA_FROM_DEVICE);
305 	kfree(isert_conn->login_req_buf);
306 }
307 
308 static int
309 isert_alloc_login_buf(struct isert_conn *isert_conn,
310 		      struct ib_device *ib_dev)
311 {
312 	int ret;
313 
314 	isert_conn->login_req_buf = kzalloc(sizeof(*isert_conn->login_req_buf),
315 			GFP_KERNEL);
316 	if (!isert_conn->login_req_buf)
317 		return -ENOMEM;
318 
319 	isert_conn->login_req_dma = ib_dma_map_single(ib_dev,
320 				isert_conn->login_req_buf,
321 				ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
322 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_req_dma);
323 	if (ret) {
324 		isert_err("login_req_dma mapping error: %d\n", ret);
325 		isert_conn->login_req_dma = 0;
326 		goto out_free_login_req_buf;
327 	}
328 
329 	isert_conn->login_rsp_buf = kzalloc(ISER_RX_PAYLOAD_SIZE, GFP_KERNEL);
330 	if (!isert_conn->login_rsp_buf) {
331 		ret = -ENOMEM;
332 		goto out_unmap_login_req_buf;
333 	}
334 
335 	isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
336 					isert_conn->login_rsp_buf,
337 					ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
338 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
339 	if (ret) {
340 		isert_err("login_rsp_dma mapping error: %d\n", ret);
341 		isert_conn->login_rsp_dma = 0;
342 		goto out_free_login_rsp_buf;
343 	}
344 
345 	return 0;
346 
347 out_free_login_rsp_buf:
348 	kfree(isert_conn->login_rsp_buf);
349 out_unmap_login_req_buf:
350 	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
351 			    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
352 out_free_login_req_buf:
353 	kfree(isert_conn->login_req_buf);
354 	return ret;
355 }
356 
357 static void
358 isert_set_nego_params(struct isert_conn *isert_conn,
359 		      struct rdma_conn_param *param)
360 {
361 	struct ib_device_attr *attr = &isert_conn->device->ib_device->attrs;
362 
363 	/* Set max inflight RDMA READ requests */
364 	isert_conn->initiator_depth = min_t(u8, param->initiator_depth,
365 				attr->max_qp_init_rd_atom);
366 	isert_dbg("Using initiator_depth: %u\n", isert_conn->initiator_depth);
367 
368 	if (param->private_data) {
369 		u8 flags = *(u8 *)param->private_data;
370 
371 		/*
372 		 * use remote invalidation if the both initiator
373 		 * and the HCA support it
374 		 */
375 		isert_conn->snd_w_inv = !(flags & ISER_SEND_W_INV_NOT_SUP) &&
376 					  (attr->device_cap_flags &
377 					   IB_DEVICE_MEM_MGT_EXTENSIONS);
378 		if (isert_conn->snd_w_inv)
379 			isert_info("Using remote invalidation\n");
380 	}
381 }
382 
383 static void
384 isert_destroy_qp(struct isert_conn *isert_conn)
385 {
386 	ib_destroy_qp(isert_conn->qp);
387 	ib_cq_pool_put(isert_conn->cq, isert_conn->cq_size);
388 }
389 
390 static int
391 isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
392 {
393 	struct isert_np *isert_np = cma_id->context;
394 	struct iscsi_np *np = isert_np->np;
395 	struct isert_conn *isert_conn;
396 	struct isert_device *device;
397 	int ret = 0;
398 
399 	spin_lock_bh(&np->np_thread_lock);
400 	if (!np->enabled) {
401 		spin_unlock_bh(&np->np_thread_lock);
402 		isert_dbg("iscsi_np is not enabled, reject connect request\n");
403 		return rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
404 	}
405 	spin_unlock_bh(&np->np_thread_lock);
406 
407 	isert_dbg("cma_id: %p, portal: %p\n",
408 		 cma_id, cma_id->context);
409 
410 	isert_conn = kzalloc(sizeof(struct isert_conn), GFP_KERNEL);
411 	if (!isert_conn)
412 		return -ENOMEM;
413 
414 	isert_init_conn(isert_conn);
415 	isert_conn->cm_id = cma_id;
416 
417 	ret = isert_alloc_login_buf(isert_conn, cma_id->device);
418 	if (ret)
419 		goto out;
420 
421 	device = isert_device_get(cma_id);
422 	if (IS_ERR(device)) {
423 		ret = PTR_ERR(device);
424 		goto out_rsp_dma_map;
425 	}
426 	isert_conn->device = device;
427 
428 	isert_set_nego_params(isert_conn, &event->param.conn);
429 
430 	isert_conn->qp = isert_create_qp(isert_conn, cma_id);
431 	if (IS_ERR(isert_conn->qp)) {
432 		ret = PTR_ERR(isert_conn->qp);
433 		goto out_conn_dev;
434 	}
435 
436 	ret = isert_login_post_recv(isert_conn);
437 	if (ret)
438 		goto out_destroy_qp;
439 
440 	ret = isert_rdma_accept(isert_conn);
441 	if (ret)
442 		goto out_destroy_qp;
443 
444 	mutex_lock(&isert_np->mutex);
445 	list_add_tail(&isert_conn->node, &isert_np->accepted);
446 	mutex_unlock(&isert_np->mutex);
447 
448 	return 0;
449 
450 out_destroy_qp:
451 	isert_destroy_qp(isert_conn);
452 out_conn_dev:
453 	isert_device_put(device);
454 out_rsp_dma_map:
455 	isert_free_login_buf(isert_conn);
456 out:
457 	kfree(isert_conn);
458 	rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
459 	return ret;
460 }
461 
462 static void
463 isert_connect_release(struct isert_conn *isert_conn)
464 {
465 	struct isert_device *device = isert_conn->device;
466 
467 	isert_dbg("conn %p\n", isert_conn);
468 
469 	BUG_ON(!device);
470 
471 	isert_free_rx_descriptors(isert_conn);
472 	if (isert_conn->cm_id &&
473 	    !isert_conn->dev_removed)
474 		rdma_destroy_id(isert_conn->cm_id);
475 
476 	if (isert_conn->qp)
477 		isert_destroy_qp(isert_conn);
478 
479 	if (isert_conn->login_req_buf)
480 		isert_free_login_buf(isert_conn);
481 
482 	isert_device_put(device);
483 
484 	if (isert_conn->dev_removed)
485 		wake_up_interruptible(&isert_conn->rem_wait);
486 	else
487 		kfree(isert_conn);
488 }
489 
490 static void
491 isert_connected_handler(struct rdma_cm_id *cma_id)
492 {
493 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
494 	struct isert_np *isert_np = cma_id->context;
495 
496 	isert_info("conn %p\n", isert_conn);
497 
498 	mutex_lock(&isert_conn->mutex);
499 	isert_conn->state = ISER_CONN_UP;
500 	kref_get(&isert_conn->kref);
501 	mutex_unlock(&isert_conn->mutex);
502 
503 	mutex_lock(&isert_np->mutex);
504 	list_move_tail(&isert_conn->node, &isert_np->pending);
505 	mutex_unlock(&isert_np->mutex);
506 
507 	isert_info("np %p: Allow accept_np to continue\n", isert_np);
508 	up(&isert_np->sem);
509 }
510 
511 static void
512 isert_release_kref(struct kref *kref)
513 {
514 	struct isert_conn *isert_conn = container_of(kref,
515 				struct isert_conn, kref);
516 
517 	isert_info("conn %p final kref %s/%d\n", isert_conn, current->comm,
518 		   current->pid);
519 
520 	isert_connect_release(isert_conn);
521 }
522 
523 static void
524 isert_put_conn(struct isert_conn *isert_conn)
525 {
526 	kref_put(&isert_conn->kref, isert_release_kref);
527 }
528 
529 static void
530 isert_handle_unbound_conn(struct isert_conn *isert_conn)
531 {
532 	struct isert_np *isert_np = isert_conn->cm_id->context;
533 
534 	mutex_lock(&isert_np->mutex);
535 	if (!list_empty(&isert_conn->node)) {
536 		/*
537 		 * This means iscsi doesn't know this connection
538 		 * so schedule a cleanup ourselves
539 		 */
540 		list_del_init(&isert_conn->node);
541 		isert_put_conn(isert_conn);
542 		queue_work(isert_release_wq, &isert_conn->release_work);
543 	}
544 	mutex_unlock(&isert_np->mutex);
545 }
546 
547 /**
548  * isert_conn_terminate() - Initiate connection termination
549  * @isert_conn: isert connection struct
550  *
551  * Notes:
552  * In case the connection state is BOUND, move state
553  * to TEMINATING and start teardown sequence (rdma_disconnect).
554  * In case the connection state is UP, complete flush as well.
555  *
556  * This routine must be called with mutex held. Thus it is
557  * safe to call multiple times.
558  */
559 static void
560 isert_conn_terminate(struct isert_conn *isert_conn)
561 {
562 	int err;
563 
564 	if (isert_conn->state >= ISER_CONN_TERMINATING)
565 		return;
566 
567 	isert_info("Terminating conn %p state %d\n",
568 		   isert_conn, isert_conn->state);
569 	isert_conn->state = ISER_CONN_TERMINATING;
570 	err = rdma_disconnect(isert_conn->cm_id);
571 	if (err)
572 		isert_warn("Failed rdma_disconnect isert_conn %p\n",
573 			   isert_conn);
574 }
575 
576 static int
577 isert_np_cma_handler(struct isert_np *isert_np,
578 		     enum rdma_cm_event_type event)
579 {
580 	isert_dbg("%s (%d): isert np %p\n",
581 		  rdma_event_msg(event), event, isert_np);
582 
583 	switch (event) {
584 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
585 		isert_np->cm_id = NULL;
586 		break;
587 	case RDMA_CM_EVENT_ADDR_CHANGE:
588 		isert_np->cm_id = isert_setup_id(isert_np);
589 		if (IS_ERR(isert_np->cm_id)) {
590 			isert_err("isert np %p setup id failed: %ld\n",
591 				  isert_np, PTR_ERR(isert_np->cm_id));
592 			isert_np->cm_id = NULL;
593 		}
594 		break;
595 	default:
596 		isert_err("isert np %p Unexpected event %d\n",
597 			  isert_np, event);
598 	}
599 
600 	return -1;
601 }
602 
603 static int
604 isert_disconnected_handler(struct rdma_cm_id *cma_id,
605 			   enum rdma_cm_event_type event)
606 {
607 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
608 
609 	mutex_lock(&isert_conn->mutex);
610 	switch (isert_conn->state) {
611 	case ISER_CONN_TERMINATING:
612 		break;
613 	case ISER_CONN_UP:
614 		isert_conn_terminate(isert_conn);
615 		ib_drain_qp(isert_conn->qp);
616 		isert_handle_unbound_conn(isert_conn);
617 		break;
618 	case ISER_CONN_BOUND:
619 	case ISER_CONN_FULL_FEATURE: /* FALLTHRU */
620 		iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
621 		break;
622 	default:
623 		isert_warn("conn %p terminating in state %d\n",
624 			   isert_conn, isert_conn->state);
625 	}
626 	mutex_unlock(&isert_conn->mutex);
627 
628 	return 0;
629 }
630 
631 static int
632 isert_connect_error(struct rdma_cm_id *cma_id)
633 {
634 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
635 
636 	ib_drain_qp(isert_conn->qp);
637 	list_del_init(&isert_conn->node);
638 	isert_conn->cm_id = NULL;
639 	isert_put_conn(isert_conn);
640 
641 	return -1;
642 }
643 
644 static int
645 isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
646 {
647 	struct isert_np *isert_np = cma_id->context;
648 	struct isert_conn *isert_conn;
649 	int ret = 0;
650 
651 	isert_info("%s (%d): status %d id %p np %p\n",
652 		   rdma_event_msg(event->event), event->event,
653 		   event->status, cma_id, cma_id->context);
654 
655 	if (isert_np->cm_id == cma_id)
656 		return isert_np_cma_handler(cma_id->context, event->event);
657 
658 	switch (event->event) {
659 	case RDMA_CM_EVENT_CONNECT_REQUEST:
660 		ret = isert_connect_request(cma_id, event);
661 		if (ret)
662 			isert_err("failed handle connect request %d\n", ret);
663 		break;
664 	case RDMA_CM_EVENT_ESTABLISHED:
665 		isert_connected_handler(cma_id);
666 		break;
667 	case RDMA_CM_EVENT_ADDR_CHANGE:    /* FALLTHRU */
668 	case RDMA_CM_EVENT_DISCONNECTED:   /* FALLTHRU */
669 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:  /* FALLTHRU */
670 		ret = isert_disconnected_handler(cma_id, event->event);
671 		break;
672 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
673 		isert_conn = cma_id->qp->qp_context;
674 		isert_conn->dev_removed = true;
675 		isert_disconnected_handler(cma_id, event->event);
676 		wait_event_interruptible(isert_conn->rem_wait,
677 					 isert_conn->state == ISER_CONN_DOWN);
678 		kfree(isert_conn);
679 		/*
680 		 * return non-zero from the callback to destroy
681 		 * the rdma cm id
682 		 */
683 		return 1;
684 	case RDMA_CM_EVENT_REJECTED:
685 		isert_info("Connection rejected: %s\n",
686 			   rdma_reject_msg(cma_id, event->status));
687 		/* fall through */
688 	case RDMA_CM_EVENT_UNREACHABLE:
689 	case RDMA_CM_EVENT_CONNECT_ERROR:
690 		ret = isert_connect_error(cma_id);
691 		break;
692 	default:
693 		isert_err("Unhandled RDMA CMA event: %d\n", event->event);
694 		break;
695 	}
696 
697 	return ret;
698 }
699 
700 static int
701 isert_post_recvm(struct isert_conn *isert_conn, u32 count)
702 {
703 	struct ib_recv_wr *rx_wr;
704 	int i, ret;
705 	struct iser_rx_desc *rx_desc;
706 
707 	for (rx_wr = isert_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
708 		rx_desc = &isert_conn->rx_descs[i];
709 
710 		rx_wr->wr_cqe = &rx_desc->rx_cqe;
711 		rx_wr->sg_list = &rx_desc->rx_sg;
712 		rx_wr->num_sge = 1;
713 		rx_wr->next = rx_wr + 1;
714 		rx_desc->in_use = false;
715 	}
716 	rx_wr--;
717 	rx_wr->next = NULL; /* mark end of work requests list */
718 
719 	ret = ib_post_recv(isert_conn->qp, isert_conn->rx_wr, NULL);
720 	if (ret)
721 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
722 
723 	return ret;
724 }
725 
726 static int
727 isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
728 {
729 	struct ib_recv_wr rx_wr;
730 	int ret;
731 
732 	if (!rx_desc->in_use) {
733 		/*
734 		 * if the descriptor is not in-use we already reposted it
735 		 * for recv, so just silently return
736 		 */
737 		return 0;
738 	}
739 
740 	rx_desc->in_use = false;
741 	rx_wr.wr_cqe = &rx_desc->rx_cqe;
742 	rx_wr.sg_list = &rx_desc->rx_sg;
743 	rx_wr.num_sge = 1;
744 	rx_wr.next = NULL;
745 
746 	ret = ib_post_recv(isert_conn->qp, &rx_wr, NULL);
747 	if (ret)
748 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
749 
750 	return ret;
751 }
752 
753 static int
754 isert_login_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
755 {
756 	struct ib_device *ib_dev = isert_conn->cm_id->device;
757 	struct ib_send_wr send_wr;
758 	int ret;
759 
760 	ib_dma_sync_single_for_device(ib_dev, tx_desc->dma_addr,
761 				      ISER_HEADERS_LEN, DMA_TO_DEVICE);
762 
763 	tx_desc->tx_cqe.done = isert_login_send_done;
764 
765 	send_wr.next	= NULL;
766 	send_wr.wr_cqe	= &tx_desc->tx_cqe;
767 	send_wr.sg_list	= tx_desc->tx_sg;
768 	send_wr.num_sge	= tx_desc->num_sge;
769 	send_wr.opcode	= IB_WR_SEND;
770 	send_wr.send_flags = IB_SEND_SIGNALED;
771 
772 	ret = ib_post_send(isert_conn->qp, &send_wr, NULL);
773 	if (ret)
774 		isert_err("ib_post_send() failed, ret: %d\n", ret);
775 
776 	return ret;
777 }
778 
779 static void
780 __isert_create_send_desc(struct isert_device *device,
781 			 struct iser_tx_desc *tx_desc)
782 {
783 
784 	memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl));
785 	tx_desc->iser_header.flags = ISCSI_CTRL;
786 
787 	tx_desc->num_sge = 1;
788 
789 	if (tx_desc->tx_sg[0].lkey != device->pd->local_dma_lkey) {
790 		tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
791 		isert_dbg("tx_desc %p lkey mismatch, fixing\n", tx_desc);
792 	}
793 }
794 
795 static void
796 isert_create_send_desc(struct isert_conn *isert_conn,
797 		       struct isert_cmd *isert_cmd,
798 		       struct iser_tx_desc *tx_desc)
799 {
800 	struct isert_device *device = isert_conn->device;
801 	struct ib_device *ib_dev = device->ib_device;
802 
803 	ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr,
804 				   ISER_HEADERS_LEN, DMA_TO_DEVICE);
805 
806 	__isert_create_send_desc(device, tx_desc);
807 }
808 
809 static int
810 isert_init_tx_hdrs(struct isert_conn *isert_conn,
811 		   struct iser_tx_desc *tx_desc)
812 {
813 	struct isert_device *device = isert_conn->device;
814 	struct ib_device *ib_dev = device->ib_device;
815 	u64 dma_addr;
816 
817 	dma_addr = ib_dma_map_single(ib_dev, (void *)tx_desc,
818 			ISER_HEADERS_LEN, DMA_TO_DEVICE);
819 	if (ib_dma_mapping_error(ib_dev, dma_addr)) {
820 		isert_err("ib_dma_mapping_error() failed\n");
821 		return -ENOMEM;
822 	}
823 
824 	tx_desc->dma_addr = dma_addr;
825 	tx_desc->tx_sg[0].addr	= tx_desc->dma_addr;
826 	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
827 	tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
828 
829 	isert_dbg("Setup tx_sg[0].addr: 0x%llx length: %u lkey: 0x%x\n",
830 		  tx_desc->tx_sg[0].addr, tx_desc->tx_sg[0].length,
831 		  tx_desc->tx_sg[0].lkey);
832 
833 	return 0;
834 }
835 
836 static void
837 isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
838 		   struct ib_send_wr *send_wr)
839 {
840 	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
841 
842 	tx_desc->tx_cqe.done = isert_send_done;
843 	send_wr->wr_cqe = &tx_desc->tx_cqe;
844 
845 	if (isert_conn->snd_w_inv && isert_cmd->inv_rkey) {
846 		send_wr->opcode  = IB_WR_SEND_WITH_INV;
847 		send_wr->ex.invalidate_rkey = isert_cmd->inv_rkey;
848 	} else {
849 		send_wr->opcode = IB_WR_SEND;
850 	}
851 
852 	send_wr->sg_list = &tx_desc->tx_sg[0];
853 	send_wr->num_sge = isert_cmd->tx_desc.num_sge;
854 	send_wr->send_flags = IB_SEND_SIGNALED;
855 }
856 
857 static int
858 isert_login_post_recv(struct isert_conn *isert_conn)
859 {
860 	struct ib_recv_wr rx_wr;
861 	struct ib_sge sge;
862 	int ret;
863 
864 	memset(&sge, 0, sizeof(struct ib_sge));
865 	sge.addr = isert_conn->login_req_dma;
866 	sge.length = ISER_RX_PAYLOAD_SIZE;
867 	sge.lkey = isert_conn->device->pd->local_dma_lkey;
868 
869 	isert_dbg("Setup sge: addr: %llx length: %d 0x%08x\n",
870 		sge.addr, sge.length, sge.lkey);
871 
872 	isert_conn->login_req_buf->rx_cqe.done = isert_login_recv_done;
873 
874 	memset(&rx_wr, 0, sizeof(struct ib_recv_wr));
875 	rx_wr.wr_cqe = &isert_conn->login_req_buf->rx_cqe;
876 	rx_wr.sg_list = &sge;
877 	rx_wr.num_sge = 1;
878 
879 	ret = ib_post_recv(isert_conn->qp, &rx_wr, NULL);
880 	if (ret)
881 		isert_err("ib_post_recv() failed: %d\n", ret);
882 
883 	return ret;
884 }
885 
886 static int
887 isert_put_login_tx(struct iscsi_conn *conn, struct iscsi_login *login,
888 		   u32 length)
889 {
890 	struct isert_conn *isert_conn = conn->context;
891 	struct isert_device *device = isert_conn->device;
892 	struct ib_device *ib_dev = device->ib_device;
893 	struct iser_tx_desc *tx_desc = &isert_conn->login_tx_desc;
894 	int ret;
895 
896 	__isert_create_send_desc(device, tx_desc);
897 
898 	memcpy(&tx_desc->iscsi_header, &login->rsp[0],
899 	       sizeof(struct iscsi_hdr));
900 
901 	isert_init_tx_hdrs(isert_conn, tx_desc);
902 
903 	if (length > 0) {
904 		struct ib_sge *tx_dsg = &tx_desc->tx_sg[1];
905 
906 		ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_rsp_dma,
907 					   length, DMA_TO_DEVICE);
908 
909 		memcpy(isert_conn->login_rsp_buf, login->rsp_buf, length);
910 
911 		ib_dma_sync_single_for_device(ib_dev, isert_conn->login_rsp_dma,
912 					      length, DMA_TO_DEVICE);
913 
914 		tx_dsg->addr	= isert_conn->login_rsp_dma;
915 		tx_dsg->length	= length;
916 		tx_dsg->lkey	= isert_conn->device->pd->local_dma_lkey;
917 		tx_desc->num_sge = 2;
918 	}
919 	if (!login->login_failed) {
920 		if (login->login_complete) {
921 			ret = isert_alloc_rx_descriptors(isert_conn);
922 			if (ret)
923 				return ret;
924 
925 			ret = isert_post_recvm(isert_conn,
926 					       ISERT_QP_MAX_RECV_DTOS);
927 			if (ret)
928 				return ret;
929 
930 			/* Now we are in FULL_FEATURE phase */
931 			mutex_lock(&isert_conn->mutex);
932 			isert_conn->state = ISER_CONN_FULL_FEATURE;
933 			mutex_unlock(&isert_conn->mutex);
934 			goto post_send;
935 		}
936 
937 		ret = isert_login_post_recv(isert_conn);
938 		if (ret)
939 			return ret;
940 	}
941 post_send:
942 	ret = isert_login_post_send(isert_conn, tx_desc);
943 	if (ret)
944 		return ret;
945 
946 	return 0;
947 }
948 
949 static void
950 isert_rx_login_req(struct isert_conn *isert_conn)
951 {
952 	struct iser_rx_desc *rx_desc = isert_conn->login_req_buf;
953 	int rx_buflen = isert_conn->login_req_len;
954 	struct iscsi_conn *conn = isert_conn->conn;
955 	struct iscsi_login *login = conn->conn_login;
956 	int size;
957 
958 	isert_info("conn %p\n", isert_conn);
959 
960 	WARN_ON_ONCE(!login);
961 
962 	if (login->first_request) {
963 		struct iscsi_login_req *login_req =
964 			(struct iscsi_login_req *)&rx_desc->iscsi_header;
965 		/*
966 		 * Setup the initial iscsi_login values from the leading
967 		 * login request PDU.
968 		 */
969 		login->leading_connection = (!login_req->tsih) ? 1 : 0;
970 		login->current_stage =
971 			(login_req->flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK)
972 			 >> 2;
973 		login->version_min	= login_req->min_version;
974 		login->version_max	= login_req->max_version;
975 		memcpy(login->isid, login_req->isid, 6);
976 		login->cmd_sn		= be32_to_cpu(login_req->cmdsn);
977 		login->init_task_tag	= login_req->itt;
978 		login->initial_exp_statsn = be32_to_cpu(login_req->exp_statsn);
979 		login->cid		= be16_to_cpu(login_req->cid);
980 		login->tsih		= be16_to_cpu(login_req->tsih);
981 	}
982 
983 	memcpy(&login->req[0], (void *)&rx_desc->iscsi_header, ISCSI_HDR_LEN);
984 
985 	size = min(rx_buflen, MAX_KEY_VALUE_PAIRS);
986 	isert_dbg("Using login payload size: %d, rx_buflen: %d "
987 		  "MAX_KEY_VALUE_PAIRS: %d\n", size, rx_buflen,
988 		  MAX_KEY_VALUE_PAIRS);
989 	memcpy(login->req_buf, &rx_desc->data[0], size);
990 
991 	if (login->first_request) {
992 		complete(&isert_conn->login_comp);
993 		return;
994 	}
995 	schedule_delayed_work(&conn->login_work, 0);
996 }
997 
998 static struct iscsi_cmd
999 *isert_allocate_cmd(struct iscsi_conn *conn, struct iser_rx_desc *rx_desc)
1000 {
1001 	struct isert_conn *isert_conn = conn->context;
1002 	struct isert_cmd *isert_cmd;
1003 	struct iscsi_cmd *cmd;
1004 
1005 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
1006 	if (!cmd) {
1007 		isert_err("Unable to allocate iscsi_cmd + isert_cmd\n");
1008 		return NULL;
1009 	}
1010 	isert_cmd = iscsit_priv_cmd(cmd);
1011 	isert_cmd->conn = isert_conn;
1012 	isert_cmd->iscsi_cmd = cmd;
1013 	isert_cmd->rx_desc = rx_desc;
1014 
1015 	return cmd;
1016 }
1017 
1018 static int
1019 isert_handle_scsi_cmd(struct isert_conn *isert_conn,
1020 		      struct isert_cmd *isert_cmd, struct iscsi_cmd *cmd,
1021 		      struct iser_rx_desc *rx_desc, unsigned char *buf)
1022 {
1023 	struct iscsi_conn *conn = isert_conn->conn;
1024 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1025 	int imm_data, imm_data_len, unsol_data, sg_nents, rc;
1026 	bool dump_payload = false;
1027 	unsigned int data_len;
1028 
1029 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1030 	if (rc < 0)
1031 		return rc;
1032 
1033 	imm_data = cmd->immediate_data;
1034 	imm_data_len = cmd->first_burst_len;
1035 	unsol_data = cmd->unsolicited_data;
1036 	data_len = cmd->se_cmd.data_length;
1037 
1038 	if (imm_data && imm_data_len == data_len)
1039 		cmd->se_cmd.se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1040 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1041 	if (rc < 0) {
1042 		return 0;
1043 	} else if (rc > 0) {
1044 		dump_payload = true;
1045 		goto sequence_cmd;
1046 	}
1047 
1048 	if (!imm_data)
1049 		return 0;
1050 
1051 	if (imm_data_len != data_len) {
1052 		sg_nents = max(1UL, DIV_ROUND_UP(imm_data_len, PAGE_SIZE));
1053 		sg_copy_from_buffer(cmd->se_cmd.t_data_sg, sg_nents,
1054 				    &rx_desc->data[0], imm_data_len);
1055 		isert_dbg("Copy Immediate sg_nents: %u imm_data_len: %d\n",
1056 			  sg_nents, imm_data_len);
1057 	} else {
1058 		sg_init_table(&isert_cmd->sg, 1);
1059 		cmd->se_cmd.t_data_sg = &isert_cmd->sg;
1060 		cmd->se_cmd.t_data_nents = 1;
1061 		sg_set_buf(&isert_cmd->sg, &rx_desc->data[0], imm_data_len);
1062 		isert_dbg("Transfer Immediate imm_data_len: %d\n",
1063 			  imm_data_len);
1064 	}
1065 
1066 	cmd->write_data_done += imm_data_len;
1067 
1068 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
1069 		spin_lock_bh(&cmd->istate_lock);
1070 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1071 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1072 		spin_unlock_bh(&cmd->istate_lock);
1073 	}
1074 
1075 sequence_cmd:
1076 	rc = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1077 
1078 	if (!rc && dump_payload == false && unsol_data)
1079 		iscsit_set_unsolicited_dataout(cmd);
1080 	else if (dump_payload && imm_data)
1081 		target_put_sess_cmd(&cmd->se_cmd);
1082 
1083 	return 0;
1084 }
1085 
1086 static int
1087 isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
1088 			   struct iser_rx_desc *rx_desc, unsigned char *buf)
1089 {
1090 	struct scatterlist *sg_start;
1091 	struct iscsi_conn *conn = isert_conn->conn;
1092 	struct iscsi_cmd *cmd = NULL;
1093 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1094 	u32 unsol_data_len = ntoh24(hdr->dlength);
1095 	int rc, sg_nents, sg_off, page_off;
1096 
1097 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1098 	if (rc < 0)
1099 		return rc;
1100 	else if (!cmd)
1101 		return 0;
1102 	/*
1103 	 * FIXME: Unexpected unsolicited_data out
1104 	 */
1105 	if (!cmd->unsolicited_data) {
1106 		isert_err("Received unexpected solicited data payload\n");
1107 		dump_stack();
1108 		return -1;
1109 	}
1110 
1111 	isert_dbg("Unsolicited DataOut unsol_data_len: %u, "
1112 		  "write_data_done: %u, data_length: %u\n",
1113 		  unsol_data_len,  cmd->write_data_done,
1114 		  cmd->se_cmd.data_length);
1115 
1116 	sg_off = cmd->write_data_done / PAGE_SIZE;
1117 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
1118 	sg_nents = max(1UL, DIV_ROUND_UP(unsol_data_len, PAGE_SIZE));
1119 	page_off = cmd->write_data_done % PAGE_SIZE;
1120 	/*
1121 	 * FIXME: Non page-aligned unsolicited_data out
1122 	 */
1123 	if (page_off) {
1124 		isert_err("unexpected non-page aligned data payload\n");
1125 		dump_stack();
1126 		return -1;
1127 	}
1128 	isert_dbg("Copying DataOut: sg_start: %p, sg_off: %u "
1129 		  "sg_nents: %u from %p %u\n", sg_start, sg_off,
1130 		  sg_nents, &rx_desc->data[0], unsol_data_len);
1131 
1132 	sg_copy_from_buffer(sg_start, sg_nents, &rx_desc->data[0],
1133 			    unsol_data_len);
1134 
1135 	rc = iscsit_check_dataout_payload(cmd, hdr, false);
1136 	if (rc < 0)
1137 		return rc;
1138 
1139 	/*
1140 	 * multiple data-outs on the same command can arrive -
1141 	 * so post the buffer before hand
1142 	 */
1143 	rc = isert_post_recv(isert_conn, rx_desc);
1144 	if (rc) {
1145 		isert_err("ib_post_recv failed with %d\n", rc);
1146 		return rc;
1147 	}
1148 	return 0;
1149 }
1150 
1151 static int
1152 isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1153 		     struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1154 		     unsigned char *buf)
1155 {
1156 	struct iscsi_conn *conn = isert_conn->conn;
1157 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1158 	int rc;
1159 
1160 	rc = iscsit_setup_nop_out(conn, cmd, hdr);
1161 	if (rc < 0)
1162 		return rc;
1163 	/*
1164 	 * FIXME: Add support for NOPOUT payload using unsolicited RDMA payload
1165 	 */
1166 
1167 	return iscsit_process_nop_out(conn, cmd, hdr);
1168 }
1169 
1170 static int
1171 isert_handle_text_cmd(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1172 		      struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1173 		      struct iscsi_text *hdr)
1174 {
1175 	struct iscsi_conn *conn = isert_conn->conn;
1176 	u32 payload_length = ntoh24(hdr->dlength);
1177 	int rc;
1178 	unsigned char *text_in = NULL;
1179 
1180 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
1181 	if (rc < 0)
1182 		return rc;
1183 
1184 	if (payload_length) {
1185 		text_in = kzalloc(payload_length, GFP_KERNEL);
1186 		if (!text_in)
1187 			return -ENOMEM;
1188 	}
1189 	cmd->text_in_ptr = text_in;
1190 
1191 	memcpy(cmd->text_in_ptr, &rx_desc->data[0], payload_length);
1192 
1193 	return iscsit_process_text_cmd(conn, cmd, hdr);
1194 }
1195 
1196 static int
1197 isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
1198 		uint32_t read_stag, uint64_t read_va,
1199 		uint32_t write_stag, uint64_t write_va)
1200 {
1201 	struct iscsi_hdr *hdr = &rx_desc->iscsi_header;
1202 	struct iscsi_conn *conn = isert_conn->conn;
1203 	struct iscsi_cmd *cmd;
1204 	struct isert_cmd *isert_cmd;
1205 	int ret = -EINVAL;
1206 	u8 opcode = (hdr->opcode & ISCSI_OPCODE_MASK);
1207 
1208 	if (conn->sess->sess_ops->SessionType &&
1209 	   (!(opcode & ISCSI_OP_TEXT) || !(opcode & ISCSI_OP_LOGOUT))) {
1210 		isert_err("Got illegal opcode: 0x%02x in SessionType=Discovery,"
1211 			  " ignoring\n", opcode);
1212 		return 0;
1213 	}
1214 
1215 	switch (opcode) {
1216 	case ISCSI_OP_SCSI_CMD:
1217 		cmd = isert_allocate_cmd(conn, rx_desc);
1218 		if (!cmd)
1219 			break;
1220 
1221 		isert_cmd = iscsit_priv_cmd(cmd);
1222 		isert_cmd->read_stag = read_stag;
1223 		isert_cmd->read_va = read_va;
1224 		isert_cmd->write_stag = write_stag;
1225 		isert_cmd->write_va = write_va;
1226 		isert_cmd->inv_rkey = read_stag ? read_stag : write_stag;
1227 
1228 		ret = isert_handle_scsi_cmd(isert_conn, isert_cmd, cmd,
1229 					rx_desc, (unsigned char *)hdr);
1230 		break;
1231 	case ISCSI_OP_NOOP_OUT:
1232 		cmd = isert_allocate_cmd(conn, rx_desc);
1233 		if (!cmd)
1234 			break;
1235 
1236 		isert_cmd = iscsit_priv_cmd(cmd);
1237 		ret = isert_handle_nop_out(isert_conn, isert_cmd, cmd,
1238 					   rx_desc, (unsigned char *)hdr);
1239 		break;
1240 	case ISCSI_OP_SCSI_DATA_OUT:
1241 		ret = isert_handle_iscsi_dataout(isert_conn, rx_desc,
1242 						(unsigned char *)hdr);
1243 		break;
1244 	case ISCSI_OP_SCSI_TMFUNC:
1245 		cmd = isert_allocate_cmd(conn, rx_desc);
1246 		if (!cmd)
1247 			break;
1248 
1249 		ret = iscsit_handle_task_mgt_cmd(conn, cmd,
1250 						(unsigned char *)hdr);
1251 		break;
1252 	case ISCSI_OP_LOGOUT:
1253 		cmd = isert_allocate_cmd(conn, rx_desc);
1254 		if (!cmd)
1255 			break;
1256 
1257 		ret = iscsit_handle_logout_cmd(conn, cmd, (unsigned char *)hdr);
1258 		break;
1259 	case ISCSI_OP_TEXT:
1260 		if (be32_to_cpu(hdr->ttt) != 0xFFFFFFFF)
1261 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
1262 		else
1263 			cmd = isert_allocate_cmd(conn, rx_desc);
1264 
1265 		if (!cmd)
1266 			break;
1267 
1268 		isert_cmd = iscsit_priv_cmd(cmd);
1269 		ret = isert_handle_text_cmd(isert_conn, isert_cmd, cmd,
1270 					    rx_desc, (struct iscsi_text *)hdr);
1271 		break;
1272 	default:
1273 		isert_err("Got unknown iSCSI OpCode: 0x%02x\n", opcode);
1274 		dump_stack();
1275 		break;
1276 	}
1277 
1278 	return ret;
1279 }
1280 
1281 static void
1282 isert_print_wc(struct ib_wc *wc, const char *type)
1283 {
1284 	if (wc->status != IB_WC_WR_FLUSH_ERR)
1285 		isert_err("%s failure: %s (%d) vend_err %x\n", type,
1286 			  ib_wc_status_msg(wc->status), wc->status,
1287 			  wc->vendor_err);
1288 	else
1289 		isert_dbg("%s failure: %s (%d)\n", type,
1290 			  ib_wc_status_msg(wc->status), wc->status);
1291 }
1292 
1293 static void
1294 isert_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1295 {
1296 	struct isert_conn *isert_conn = wc->qp->qp_context;
1297 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1298 	struct iser_rx_desc *rx_desc = cqe_to_rx_desc(wc->wr_cqe);
1299 	struct iscsi_hdr *hdr = &rx_desc->iscsi_header;
1300 	struct iser_ctrl *iser_ctrl = &rx_desc->iser_header;
1301 	uint64_t read_va = 0, write_va = 0;
1302 	uint32_t read_stag = 0, write_stag = 0;
1303 
1304 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1305 		isert_print_wc(wc, "recv");
1306 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1307 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1308 		return;
1309 	}
1310 
1311 	rx_desc->in_use = true;
1312 
1313 	ib_dma_sync_single_for_cpu(ib_dev, rx_desc->dma_addr,
1314 			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
1315 
1316 	isert_dbg("DMA: 0x%llx, iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n",
1317 		 rx_desc->dma_addr, hdr->opcode, hdr->itt, hdr->flags,
1318 		 (int)(wc->byte_len - ISER_HEADERS_LEN));
1319 
1320 	switch (iser_ctrl->flags & 0xF0) {
1321 	case ISCSI_CTRL:
1322 		if (iser_ctrl->flags & ISER_RSV) {
1323 			read_stag = be32_to_cpu(iser_ctrl->read_stag);
1324 			read_va = be64_to_cpu(iser_ctrl->read_va);
1325 			isert_dbg("ISER_RSV: read_stag: 0x%x read_va: 0x%llx\n",
1326 				  read_stag, (unsigned long long)read_va);
1327 		}
1328 		if (iser_ctrl->flags & ISER_WSV) {
1329 			write_stag = be32_to_cpu(iser_ctrl->write_stag);
1330 			write_va = be64_to_cpu(iser_ctrl->write_va);
1331 			isert_dbg("ISER_WSV: write_stag: 0x%x write_va: 0x%llx\n",
1332 				  write_stag, (unsigned long long)write_va);
1333 		}
1334 
1335 		isert_dbg("ISER ISCSI_CTRL PDU\n");
1336 		break;
1337 	case ISER_HELLO:
1338 		isert_err("iSER Hello message\n");
1339 		break;
1340 	default:
1341 		isert_warn("Unknown iSER hdr flags: 0x%02x\n", iser_ctrl->flags);
1342 		break;
1343 	}
1344 
1345 	isert_rx_opcode(isert_conn, rx_desc,
1346 			read_stag, read_va, write_stag, write_va);
1347 
1348 	ib_dma_sync_single_for_device(ib_dev, rx_desc->dma_addr,
1349 			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
1350 }
1351 
1352 static void
1353 isert_login_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1354 {
1355 	struct isert_conn *isert_conn = wc->qp->qp_context;
1356 	struct ib_device *ib_dev = isert_conn->device->ib_device;
1357 
1358 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1359 		isert_print_wc(wc, "login recv");
1360 		return;
1361 	}
1362 
1363 	ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_req_dma,
1364 			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
1365 
1366 	isert_conn->login_req_len = wc->byte_len - ISER_HEADERS_LEN;
1367 
1368 	if (isert_conn->conn) {
1369 		struct iscsi_login *login = isert_conn->conn->conn_login;
1370 
1371 		if (login && !login->first_request)
1372 			isert_rx_login_req(isert_conn);
1373 	}
1374 
1375 	mutex_lock(&isert_conn->mutex);
1376 	complete(&isert_conn->login_req_comp);
1377 	mutex_unlock(&isert_conn->mutex);
1378 
1379 	ib_dma_sync_single_for_device(ib_dev, isert_conn->login_req_dma,
1380 				ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
1381 }
1382 
1383 static void
1384 isert_rdma_rw_ctx_destroy(struct isert_cmd *cmd, struct isert_conn *conn)
1385 {
1386 	struct se_cmd *se_cmd = &cmd->iscsi_cmd->se_cmd;
1387 	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
1388 
1389 	if (!cmd->rw.nr_ops)
1390 		return;
1391 
1392 	if (isert_prot_cmd(conn, se_cmd)) {
1393 		rdma_rw_ctx_destroy_signature(&cmd->rw, conn->qp,
1394 				conn->cm_id->port_num, se_cmd->t_data_sg,
1395 				se_cmd->t_data_nents, se_cmd->t_prot_sg,
1396 				se_cmd->t_prot_nents, dir);
1397 	} else {
1398 		rdma_rw_ctx_destroy(&cmd->rw, conn->qp, conn->cm_id->port_num,
1399 				se_cmd->t_data_sg, se_cmd->t_data_nents, dir);
1400 	}
1401 
1402 	cmd->rw.nr_ops = 0;
1403 }
1404 
1405 static void
1406 isert_put_cmd(struct isert_cmd *isert_cmd, bool comp_err)
1407 {
1408 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1409 	struct isert_conn *isert_conn = isert_cmd->conn;
1410 	struct iscsi_conn *conn = isert_conn->conn;
1411 	struct iscsi_text_rsp *hdr;
1412 
1413 	isert_dbg("Cmd %p\n", isert_cmd);
1414 
1415 	switch (cmd->iscsi_opcode) {
1416 	case ISCSI_OP_SCSI_CMD:
1417 		spin_lock_bh(&conn->cmd_lock);
1418 		if (!list_empty(&cmd->i_conn_node))
1419 			list_del_init(&cmd->i_conn_node);
1420 		spin_unlock_bh(&conn->cmd_lock);
1421 
1422 		if (cmd->data_direction == DMA_TO_DEVICE) {
1423 			iscsit_stop_dataout_timer(cmd);
1424 			/*
1425 			 * Check for special case during comp_err where
1426 			 * WRITE_PENDING has been handed off from core,
1427 			 * but requires an extra target_put_sess_cmd()
1428 			 * before transport_generic_free_cmd() below.
1429 			 */
1430 			if (comp_err &&
1431 			    cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
1432 				struct se_cmd *se_cmd = &cmd->se_cmd;
1433 
1434 				target_put_sess_cmd(se_cmd);
1435 			}
1436 		}
1437 
1438 		isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1439 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1440 		break;
1441 	case ISCSI_OP_SCSI_TMFUNC:
1442 		spin_lock_bh(&conn->cmd_lock);
1443 		if (!list_empty(&cmd->i_conn_node))
1444 			list_del_init(&cmd->i_conn_node);
1445 		spin_unlock_bh(&conn->cmd_lock);
1446 
1447 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1448 		break;
1449 	case ISCSI_OP_REJECT:
1450 	case ISCSI_OP_NOOP_OUT:
1451 	case ISCSI_OP_TEXT:
1452 		hdr = (struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1453 		/* If the continue bit is on, keep the command alive */
1454 		if (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)
1455 			break;
1456 
1457 		spin_lock_bh(&conn->cmd_lock);
1458 		if (!list_empty(&cmd->i_conn_node))
1459 			list_del_init(&cmd->i_conn_node);
1460 		spin_unlock_bh(&conn->cmd_lock);
1461 
1462 		/*
1463 		 * Handle special case for REJECT when iscsi_add_reject*() has
1464 		 * overwritten the original iscsi_opcode assignment, and the
1465 		 * associated cmd->se_cmd needs to be released.
1466 		 */
1467 		if (cmd->se_cmd.se_tfo != NULL) {
1468 			isert_dbg("Calling transport_generic_free_cmd for 0x%02x\n",
1469 				 cmd->iscsi_opcode);
1470 			transport_generic_free_cmd(&cmd->se_cmd, 0);
1471 			break;
1472 		}
1473 		/* fall through */
1474 	default:
1475 		iscsit_release_cmd(cmd);
1476 		break;
1477 	}
1478 }
1479 
1480 static void
1481 isert_unmap_tx_desc(struct iser_tx_desc *tx_desc, struct ib_device *ib_dev)
1482 {
1483 	if (tx_desc->dma_addr != 0) {
1484 		isert_dbg("unmap single for tx_desc->dma_addr\n");
1485 		ib_dma_unmap_single(ib_dev, tx_desc->dma_addr,
1486 				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
1487 		tx_desc->dma_addr = 0;
1488 	}
1489 }
1490 
1491 static void
1492 isert_completion_put(struct iser_tx_desc *tx_desc, struct isert_cmd *isert_cmd,
1493 		     struct ib_device *ib_dev, bool comp_err)
1494 {
1495 	if (isert_cmd->pdu_buf_dma != 0) {
1496 		isert_dbg("unmap single for isert_cmd->pdu_buf_dma\n");
1497 		ib_dma_unmap_single(ib_dev, isert_cmd->pdu_buf_dma,
1498 				    isert_cmd->pdu_buf_len, DMA_TO_DEVICE);
1499 		isert_cmd->pdu_buf_dma = 0;
1500 	}
1501 
1502 	isert_unmap_tx_desc(tx_desc, ib_dev);
1503 	isert_put_cmd(isert_cmd, comp_err);
1504 }
1505 
1506 static int
1507 isert_check_pi_status(struct se_cmd *se_cmd, struct ib_mr *sig_mr)
1508 {
1509 	struct ib_mr_status mr_status;
1510 	int ret;
1511 
1512 	ret = ib_check_mr_status(sig_mr, IB_MR_CHECK_SIG_STATUS, &mr_status);
1513 	if (ret) {
1514 		isert_err("ib_check_mr_status failed, ret %d\n", ret);
1515 		goto fail_mr_status;
1516 	}
1517 
1518 	if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
1519 		u64 sec_offset_err;
1520 		u32 block_size = se_cmd->se_dev->dev_attrib.block_size + 8;
1521 
1522 		switch (mr_status.sig_err.err_type) {
1523 		case IB_SIG_BAD_GUARD:
1524 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1525 			break;
1526 		case IB_SIG_BAD_REFTAG:
1527 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1528 			break;
1529 		case IB_SIG_BAD_APPTAG:
1530 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED;
1531 			break;
1532 		}
1533 		sec_offset_err = mr_status.sig_err.sig_err_offset;
1534 		do_div(sec_offset_err, block_size);
1535 		se_cmd->bad_sector = sec_offset_err + se_cmd->t_task_lba;
1536 
1537 		isert_err("PI error found type %d at sector 0x%llx "
1538 			  "expected 0x%x vs actual 0x%x\n",
1539 			  mr_status.sig_err.err_type,
1540 			  (unsigned long long)se_cmd->bad_sector,
1541 			  mr_status.sig_err.expected,
1542 			  mr_status.sig_err.actual);
1543 		ret = 1;
1544 	}
1545 
1546 fail_mr_status:
1547 	return ret;
1548 }
1549 
1550 static void
1551 isert_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
1552 {
1553 	struct isert_conn *isert_conn = wc->qp->qp_context;
1554 	struct isert_device *device = isert_conn->device;
1555 	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
1556 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
1557 	struct se_cmd *cmd = &isert_cmd->iscsi_cmd->se_cmd;
1558 	int ret = 0;
1559 
1560 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1561 		isert_print_wc(wc, "rdma write");
1562 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1563 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1564 		isert_completion_put(desc, isert_cmd, device->ib_device, true);
1565 		return;
1566 	}
1567 
1568 	isert_dbg("Cmd %p\n", isert_cmd);
1569 
1570 	ret = isert_check_pi_status(cmd, isert_cmd->rw.reg->mr);
1571 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1572 
1573 	if (ret) {
1574 		/*
1575 		 * transport_generic_request_failure() expects to have
1576 		 * plus two references to handle queue-full, so re-add
1577 		 * one here as target-core will have already dropped
1578 		 * it after the first isert_put_datain() callback.
1579 		 */
1580 		kref_get(&cmd->cmd_kref);
1581 		transport_generic_request_failure(cmd, cmd->pi_err);
1582 	} else {
1583 		/*
1584 		 * XXX: isert_put_response() failure is not retried.
1585 		 */
1586 		ret = isert_put_response(isert_conn->conn, isert_cmd->iscsi_cmd);
1587 		if (ret)
1588 			pr_warn_ratelimited("isert_put_response() ret: %d\n", ret);
1589 	}
1590 }
1591 
1592 static void
1593 isert_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc)
1594 {
1595 	struct isert_conn *isert_conn = wc->qp->qp_context;
1596 	struct isert_device *device = isert_conn->device;
1597 	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
1598 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
1599 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1600 	struct se_cmd *se_cmd = &cmd->se_cmd;
1601 	int ret = 0;
1602 
1603 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1604 		isert_print_wc(wc, "rdma read");
1605 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1606 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1607 		isert_completion_put(desc, isert_cmd, device->ib_device, true);
1608 		return;
1609 	}
1610 
1611 	isert_dbg("Cmd %p\n", isert_cmd);
1612 
1613 	iscsit_stop_dataout_timer(cmd);
1614 
1615 	if (isert_prot_cmd(isert_conn, se_cmd))
1616 		ret = isert_check_pi_status(se_cmd, isert_cmd->rw.reg->mr);
1617 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1618 	cmd->write_data_done = 0;
1619 
1620 	isert_dbg("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
1621 	spin_lock_bh(&cmd->istate_lock);
1622 	cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1623 	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1624 	spin_unlock_bh(&cmd->istate_lock);
1625 
1626 	/*
1627 	 * transport_generic_request_failure() will drop the extra
1628 	 * se_cmd->cmd_kref reference after T10-PI error, and handle
1629 	 * any non-zero ->queue_status() callback error retries.
1630 	 */
1631 	if (ret)
1632 		transport_generic_request_failure(se_cmd, se_cmd->pi_err);
1633 	else
1634 		target_execute_cmd(se_cmd);
1635 }
1636 
1637 static void
1638 isert_do_control_comp(struct work_struct *work)
1639 {
1640 	struct isert_cmd *isert_cmd = container_of(work,
1641 			struct isert_cmd, comp_work);
1642 	struct isert_conn *isert_conn = isert_cmd->conn;
1643 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1644 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1645 
1646 	isert_dbg("Cmd %p i_state %d\n", isert_cmd, cmd->i_state);
1647 
1648 	switch (cmd->i_state) {
1649 	case ISTATE_SEND_TASKMGTRSP:
1650 		iscsit_tmr_post_handler(cmd, cmd->conn);
1651 		/* fall through */
1652 	case ISTATE_SEND_REJECT:
1653 	case ISTATE_SEND_TEXTRSP:
1654 		cmd->i_state = ISTATE_SENT_STATUS;
1655 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd,
1656 				     ib_dev, false);
1657 		break;
1658 	case ISTATE_SEND_LOGOUTRSP:
1659 		iscsit_logout_post_handler(cmd, cmd->conn);
1660 		break;
1661 	default:
1662 		isert_err("Unknown i_state %d\n", cmd->i_state);
1663 		dump_stack();
1664 		break;
1665 	}
1666 }
1667 
1668 static void
1669 isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc)
1670 {
1671 	struct isert_conn *isert_conn = wc->qp->qp_context;
1672 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1673 	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
1674 
1675 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1676 		isert_print_wc(wc, "login send");
1677 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1678 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1679 	}
1680 
1681 	isert_unmap_tx_desc(tx_desc, ib_dev);
1682 }
1683 
1684 static void
1685 isert_send_done(struct ib_cq *cq, struct ib_wc *wc)
1686 {
1687 	struct isert_conn *isert_conn = wc->qp->qp_context;
1688 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1689 	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
1690 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(tx_desc);
1691 
1692 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1693 		isert_print_wc(wc, "send");
1694 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1695 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1696 		isert_completion_put(tx_desc, isert_cmd, ib_dev, true);
1697 		return;
1698 	}
1699 
1700 	isert_dbg("Cmd %p\n", isert_cmd);
1701 
1702 	switch (isert_cmd->iscsi_cmd->i_state) {
1703 	case ISTATE_SEND_TASKMGTRSP:
1704 	case ISTATE_SEND_LOGOUTRSP:
1705 	case ISTATE_SEND_REJECT:
1706 	case ISTATE_SEND_TEXTRSP:
1707 		isert_unmap_tx_desc(tx_desc, ib_dev);
1708 
1709 		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
1710 		queue_work(isert_comp_wq, &isert_cmd->comp_work);
1711 		return;
1712 	default:
1713 		isert_cmd->iscsi_cmd->i_state = ISTATE_SENT_STATUS;
1714 		isert_completion_put(tx_desc, isert_cmd, ib_dev, false);
1715 		break;
1716 	}
1717 }
1718 
1719 static int
1720 isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
1721 {
1722 	int ret;
1723 
1724 	ret = isert_post_recv(isert_conn, isert_cmd->rx_desc);
1725 	if (ret) {
1726 		isert_err("ib_post_recv failed with %d\n", ret);
1727 		return ret;
1728 	}
1729 
1730 	ret = ib_post_send(isert_conn->qp, &isert_cmd->tx_desc.send_wr, NULL);
1731 	if (ret) {
1732 		isert_err("ib_post_send failed with %d\n", ret);
1733 		return ret;
1734 	}
1735 	return ret;
1736 }
1737 
1738 static int
1739 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
1740 {
1741 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1742 	struct isert_conn *isert_conn = conn->context;
1743 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1744 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
1745 				&isert_cmd->tx_desc.iscsi_header;
1746 
1747 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1748 	iscsit_build_rsp_pdu(cmd, conn, true, hdr);
1749 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1750 	/*
1751 	 * Attach SENSE DATA payload to iSCSI Response PDU
1752 	 */
1753 	if (cmd->se_cmd.sense_buffer &&
1754 	    ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1755 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
1756 		struct isert_device *device = isert_conn->device;
1757 		struct ib_device *ib_dev = device->ib_device;
1758 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1759 		u32 padding, pdu_len;
1760 
1761 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length,
1762 				   cmd->sense_buffer);
1763 		cmd->se_cmd.scsi_sense_length += sizeof(__be16);
1764 
1765 		padding = -(cmd->se_cmd.scsi_sense_length) & 3;
1766 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
1767 		pdu_len = cmd->se_cmd.scsi_sense_length + padding;
1768 
1769 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1770 				(void *)cmd->sense_buffer, pdu_len,
1771 				DMA_TO_DEVICE);
1772 		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1773 			return -ENOMEM;
1774 
1775 		isert_cmd->pdu_buf_len = pdu_len;
1776 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1777 		tx_dsg->length	= pdu_len;
1778 		tx_dsg->lkey	= device->pd->local_dma_lkey;
1779 		isert_cmd->tx_desc.num_sge = 2;
1780 	}
1781 
1782 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1783 
1784 	isert_dbg("Posting SCSI Response\n");
1785 
1786 	return isert_post_response(isert_conn, isert_cmd);
1787 }
1788 
1789 static void
1790 isert_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
1791 {
1792 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1793 	struct isert_conn *isert_conn = conn->context;
1794 
1795 	spin_lock_bh(&conn->cmd_lock);
1796 	if (!list_empty(&cmd->i_conn_node))
1797 		list_del_init(&cmd->i_conn_node);
1798 	spin_unlock_bh(&conn->cmd_lock);
1799 
1800 	if (cmd->data_direction == DMA_TO_DEVICE)
1801 		iscsit_stop_dataout_timer(cmd);
1802 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1803 }
1804 
1805 static enum target_prot_op
1806 isert_get_sup_prot_ops(struct iscsi_conn *conn)
1807 {
1808 	struct isert_conn *isert_conn = conn->context;
1809 	struct isert_device *device = isert_conn->device;
1810 
1811 	if (conn->tpg->tpg_attrib.t10_pi) {
1812 		if (device->pi_capable) {
1813 			isert_info("conn %p PI offload enabled\n", isert_conn);
1814 			isert_conn->pi_support = true;
1815 			return TARGET_PROT_ALL;
1816 		}
1817 	}
1818 
1819 	isert_info("conn %p PI offload disabled\n", isert_conn);
1820 	isert_conn->pi_support = false;
1821 
1822 	return TARGET_PROT_NORMAL;
1823 }
1824 
1825 static int
1826 isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
1827 		bool nopout_response)
1828 {
1829 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1830 	struct isert_conn *isert_conn = conn->context;
1831 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1832 
1833 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1834 	iscsit_build_nopin_rsp(cmd, conn, (struct iscsi_nopin *)
1835 			       &isert_cmd->tx_desc.iscsi_header,
1836 			       nopout_response);
1837 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1838 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1839 
1840 	isert_dbg("conn %p Posting NOPIN Response\n", isert_conn);
1841 
1842 	return isert_post_response(isert_conn, isert_cmd);
1843 }
1844 
1845 static int
1846 isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1847 {
1848 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1849 	struct isert_conn *isert_conn = conn->context;
1850 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1851 
1852 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1853 	iscsit_build_logout_rsp(cmd, conn, (struct iscsi_logout_rsp *)
1854 				&isert_cmd->tx_desc.iscsi_header);
1855 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1856 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1857 
1858 	isert_dbg("conn %p Posting Logout Response\n", isert_conn);
1859 
1860 	return isert_post_response(isert_conn, isert_cmd);
1861 }
1862 
1863 static int
1864 isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1865 {
1866 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1867 	struct isert_conn *isert_conn = conn->context;
1868 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1869 
1870 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1871 	iscsit_build_task_mgt_rsp(cmd, conn, (struct iscsi_tm_rsp *)
1872 				  &isert_cmd->tx_desc.iscsi_header);
1873 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1874 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1875 
1876 	isert_dbg("conn %p Posting Task Management Response\n", isert_conn);
1877 
1878 	return isert_post_response(isert_conn, isert_cmd);
1879 }
1880 
1881 static int
1882 isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1883 {
1884 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1885 	struct isert_conn *isert_conn = conn->context;
1886 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1887 	struct isert_device *device = isert_conn->device;
1888 	struct ib_device *ib_dev = device->ib_device;
1889 	struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1890 	struct iscsi_reject *hdr =
1891 		(struct iscsi_reject *)&isert_cmd->tx_desc.iscsi_header;
1892 
1893 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1894 	iscsit_build_reject(cmd, conn, hdr);
1895 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1896 
1897 	hton24(hdr->dlength, ISCSI_HDR_LEN);
1898 	isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1899 			(void *)cmd->buf_ptr, ISCSI_HDR_LEN,
1900 			DMA_TO_DEVICE);
1901 	if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1902 		return -ENOMEM;
1903 	isert_cmd->pdu_buf_len = ISCSI_HDR_LEN;
1904 	tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1905 	tx_dsg->length	= ISCSI_HDR_LEN;
1906 	tx_dsg->lkey	= device->pd->local_dma_lkey;
1907 	isert_cmd->tx_desc.num_sge = 2;
1908 
1909 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1910 
1911 	isert_dbg("conn %p Posting Reject\n", isert_conn);
1912 
1913 	return isert_post_response(isert_conn, isert_cmd);
1914 }
1915 
1916 static int
1917 isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1918 {
1919 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1920 	struct isert_conn *isert_conn = conn->context;
1921 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1922 	struct iscsi_text_rsp *hdr =
1923 		(struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1924 	u32 txt_rsp_len;
1925 	int rc;
1926 
1927 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1928 	rc = iscsit_build_text_rsp(cmd, conn, hdr, ISCSI_INFINIBAND);
1929 	if (rc < 0)
1930 		return rc;
1931 
1932 	txt_rsp_len = rc;
1933 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1934 
1935 	if (txt_rsp_len) {
1936 		struct isert_device *device = isert_conn->device;
1937 		struct ib_device *ib_dev = device->ib_device;
1938 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1939 		void *txt_rsp_buf = cmd->buf_ptr;
1940 
1941 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1942 				txt_rsp_buf, txt_rsp_len, DMA_TO_DEVICE);
1943 		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1944 			return -ENOMEM;
1945 
1946 		isert_cmd->pdu_buf_len = txt_rsp_len;
1947 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1948 		tx_dsg->length	= txt_rsp_len;
1949 		tx_dsg->lkey	= device->pd->local_dma_lkey;
1950 		isert_cmd->tx_desc.num_sge = 2;
1951 	}
1952 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1953 
1954 	isert_dbg("conn %p Text Response\n", isert_conn);
1955 
1956 	return isert_post_response(isert_conn, isert_cmd);
1957 }
1958 
1959 static inline void
1960 isert_set_dif_domain(struct se_cmd *se_cmd, struct ib_sig_domain *domain)
1961 {
1962 	domain->sig_type = IB_SIG_TYPE_T10_DIF;
1963 	domain->sig.dif.bg_type = IB_T10DIF_CRC;
1964 	domain->sig.dif.pi_interval = se_cmd->se_dev->dev_attrib.block_size;
1965 	domain->sig.dif.ref_tag = se_cmd->reftag_seed;
1966 	/*
1967 	 * At the moment we hard code those, but if in the future
1968 	 * the target core would like to use it, we will take it
1969 	 * from se_cmd.
1970 	 */
1971 	domain->sig.dif.apptag_check_mask = 0xffff;
1972 	domain->sig.dif.app_escape = true;
1973 	domain->sig.dif.ref_escape = true;
1974 	if (se_cmd->prot_type == TARGET_DIF_TYPE1_PROT ||
1975 	    se_cmd->prot_type == TARGET_DIF_TYPE2_PROT)
1976 		domain->sig.dif.ref_remap = true;
1977 };
1978 
1979 static int
1980 isert_set_sig_attrs(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs)
1981 {
1982 	memset(sig_attrs, 0, sizeof(*sig_attrs));
1983 
1984 	switch (se_cmd->prot_op) {
1985 	case TARGET_PROT_DIN_INSERT:
1986 	case TARGET_PROT_DOUT_STRIP:
1987 		sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
1988 		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
1989 		break;
1990 	case TARGET_PROT_DOUT_INSERT:
1991 	case TARGET_PROT_DIN_STRIP:
1992 		sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
1993 		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
1994 		break;
1995 	case TARGET_PROT_DIN_PASS:
1996 	case TARGET_PROT_DOUT_PASS:
1997 		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
1998 		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
1999 		break;
2000 	default:
2001 		isert_err("Unsupported PI operation %d\n", se_cmd->prot_op);
2002 		return -EINVAL;
2003 	}
2004 
2005 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_GUARD)
2006 		sig_attrs->check_mask |= IB_SIG_CHECK_GUARD;
2007 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_APPTAG)
2008 		sig_attrs->check_mask |= IB_SIG_CHECK_APPTAG;
2009 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)
2010 		sig_attrs->check_mask |= IB_SIG_CHECK_REFTAG;
2011 
2012 	return 0;
2013 }
2014 
2015 static int
2016 isert_rdma_rw_ctx_post(struct isert_cmd *cmd, struct isert_conn *conn,
2017 		struct ib_cqe *cqe, struct ib_send_wr *chain_wr)
2018 {
2019 	struct se_cmd *se_cmd = &cmd->iscsi_cmd->se_cmd;
2020 	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
2021 	u8 port_num = conn->cm_id->port_num;
2022 	u64 addr;
2023 	u32 rkey, offset;
2024 	int ret;
2025 
2026 	if (cmd->ctx_init_done)
2027 		goto rdma_ctx_post;
2028 
2029 	if (dir == DMA_FROM_DEVICE) {
2030 		addr = cmd->write_va;
2031 		rkey = cmd->write_stag;
2032 		offset = cmd->iscsi_cmd->write_data_done;
2033 	} else {
2034 		addr = cmd->read_va;
2035 		rkey = cmd->read_stag;
2036 		offset = 0;
2037 	}
2038 
2039 	if (isert_prot_cmd(conn, se_cmd)) {
2040 		struct ib_sig_attrs sig_attrs;
2041 
2042 		ret = isert_set_sig_attrs(se_cmd, &sig_attrs);
2043 		if (ret)
2044 			return ret;
2045 
2046 		WARN_ON_ONCE(offset);
2047 		ret = rdma_rw_ctx_signature_init(&cmd->rw, conn->qp, port_num,
2048 				se_cmd->t_data_sg, se_cmd->t_data_nents,
2049 				se_cmd->t_prot_sg, se_cmd->t_prot_nents,
2050 				&sig_attrs, addr, rkey, dir);
2051 	} else {
2052 		ret = rdma_rw_ctx_init(&cmd->rw, conn->qp, port_num,
2053 				se_cmd->t_data_sg, se_cmd->t_data_nents,
2054 				offset, addr, rkey, dir);
2055 	}
2056 
2057 	if (ret < 0) {
2058 		isert_err("Cmd: %p failed to prepare RDMA res\n", cmd);
2059 		return ret;
2060 	}
2061 
2062 	cmd->ctx_init_done = true;
2063 
2064 rdma_ctx_post:
2065 	ret = rdma_rw_ctx_post(&cmd->rw, conn->qp, port_num, cqe, chain_wr);
2066 	if (ret < 0)
2067 		isert_err("Cmd: %p failed to post RDMA res\n", cmd);
2068 	return ret;
2069 }
2070 
2071 static int
2072 isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
2073 {
2074 	struct se_cmd *se_cmd = &cmd->se_cmd;
2075 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2076 	struct isert_conn *isert_conn = conn->context;
2077 	struct ib_cqe *cqe = NULL;
2078 	struct ib_send_wr *chain_wr = NULL;
2079 	int rc;
2080 
2081 	isert_dbg("Cmd: %p RDMA_WRITE data_length: %u\n",
2082 		 isert_cmd, se_cmd->data_length);
2083 
2084 	if (isert_prot_cmd(isert_conn, se_cmd)) {
2085 		isert_cmd->tx_desc.tx_cqe.done = isert_rdma_write_done;
2086 		cqe = &isert_cmd->tx_desc.tx_cqe;
2087 	} else {
2088 		/*
2089 		 * Build isert_conn->tx_desc for iSCSI response PDU and attach
2090 		 */
2091 		isert_create_send_desc(isert_conn, isert_cmd,
2092 				       &isert_cmd->tx_desc);
2093 		iscsit_build_rsp_pdu(cmd, conn, true, (struct iscsi_scsi_rsp *)
2094 				     &isert_cmd->tx_desc.iscsi_header);
2095 		isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2096 		isert_init_send_wr(isert_conn, isert_cmd,
2097 				   &isert_cmd->tx_desc.send_wr);
2098 
2099 		rc = isert_post_recv(isert_conn, isert_cmd->rx_desc);
2100 		if (rc) {
2101 			isert_err("ib_post_recv failed with %d\n", rc);
2102 			return rc;
2103 		}
2104 
2105 		chain_wr = &isert_cmd->tx_desc.send_wr;
2106 	}
2107 
2108 	rc = isert_rdma_rw_ctx_post(isert_cmd, isert_conn, cqe, chain_wr);
2109 	isert_dbg("Cmd: %p posted RDMA_WRITE for iSER Data READ rc: %d\n",
2110 		  isert_cmd, rc);
2111 	return rc;
2112 }
2113 
2114 static int
2115 isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
2116 {
2117 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2118 	int ret;
2119 
2120 	isert_dbg("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
2121 		 isert_cmd, cmd->se_cmd.data_length, cmd->write_data_done);
2122 
2123 	isert_cmd->tx_desc.tx_cqe.done = isert_rdma_read_done;
2124 	ret = isert_rdma_rw_ctx_post(isert_cmd, conn->context,
2125 				     &isert_cmd->tx_desc.tx_cqe, NULL);
2126 
2127 	isert_dbg("Cmd: %p posted RDMA_READ memory for ISER Data WRITE rc: %d\n",
2128 		 isert_cmd, ret);
2129 	return ret;
2130 }
2131 
2132 static int
2133 isert_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2134 {
2135 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2136 	int ret = 0;
2137 
2138 	switch (state) {
2139 	case ISTATE_REMOVE:
2140 		spin_lock_bh(&conn->cmd_lock);
2141 		list_del_init(&cmd->i_conn_node);
2142 		spin_unlock_bh(&conn->cmd_lock);
2143 		isert_put_cmd(isert_cmd, true);
2144 		break;
2145 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
2146 		ret = isert_put_nopin(cmd, conn, false);
2147 		break;
2148 	default:
2149 		isert_err("Unknown immediate state: 0x%02x\n", state);
2150 		ret = -EINVAL;
2151 		break;
2152 	}
2153 
2154 	return ret;
2155 }
2156 
2157 static int
2158 isert_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2159 {
2160 	struct isert_conn *isert_conn = conn->context;
2161 	int ret;
2162 
2163 	switch (state) {
2164 	case ISTATE_SEND_LOGOUTRSP:
2165 		ret = isert_put_logout_rsp(cmd, conn);
2166 		if (!ret)
2167 			isert_conn->logout_posted = true;
2168 		break;
2169 	case ISTATE_SEND_NOPIN:
2170 		ret = isert_put_nopin(cmd, conn, true);
2171 		break;
2172 	case ISTATE_SEND_TASKMGTRSP:
2173 		ret = isert_put_tm_rsp(cmd, conn);
2174 		break;
2175 	case ISTATE_SEND_REJECT:
2176 		ret = isert_put_reject(cmd, conn);
2177 		break;
2178 	case ISTATE_SEND_TEXTRSP:
2179 		ret = isert_put_text_rsp(cmd, conn);
2180 		break;
2181 	case ISTATE_SEND_STATUS:
2182 		/*
2183 		 * Special case for sending non GOOD SCSI status from TX thread
2184 		 * context during pre se_cmd excecution failure.
2185 		 */
2186 		ret = isert_put_response(conn, cmd);
2187 		break;
2188 	default:
2189 		isert_err("Unknown response state: 0x%02x\n", state);
2190 		ret = -EINVAL;
2191 		break;
2192 	}
2193 
2194 	return ret;
2195 }
2196 
2197 struct rdma_cm_id *
2198 isert_setup_id(struct isert_np *isert_np)
2199 {
2200 	struct iscsi_np *np = isert_np->np;
2201 	struct rdma_cm_id *id;
2202 	struct sockaddr *sa;
2203 	int ret;
2204 
2205 	sa = (struct sockaddr *)&np->np_sockaddr;
2206 	isert_dbg("ksockaddr: %p, sa: %p\n", &np->np_sockaddr, sa);
2207 
2208 	id = rdma_create_id(&init_net, isert_cma_handler, isert_np,
2209 			    RDMA_PS_TCP, IB_QPT_RC);
2210 	if (IS_ERR(id)) {
2211 		isert_err("rdma_create_id() failed: %ld\n", PTR_ERR(id));
2212 		ret = PTR_ERR(id);
2213 		goto out;
2214 	}
2215 	isert_dbg("id %p context %p\n", id, id->context);
2216 
2217 	ret = rdma_bind_addr(id, sa);
2218 	if (ret) {
2219 		isert_err("rdma_bind_addr() failed: %d\n", ret);
2220 		goto out_id;
2221 	}
2222 
2223 	ret = rdma_listen(id, 0);
2224 	if (ret) {
2225 		isert_err("rdma_listen() failed: %d\n", ret);
2226 		goto out_id;
2227 	}
2228 
2229 	return id;
2230 out_id:
2231 	rdma_destroy_id(id);
2232 out:
2233 	return ERR_PTR(ret);
2234 }
2235 
2236 static int
2237 isert_setup_np(struct iscsi_np *np,
2238 	       struct sockaddr_storage *ksockaddr)
2239 {
2240 	struct isert_np *isert_np;
2241 	struct rdma_cm_id *isert_lid;
2242 	int ret;
2243 
2244 	isert_np = kzalloc(sizeof(struct isert_np), GFP_KERNEL);
2245 	if (!isert_np)
2246 		return -ENOMEM;
2247 
2248 	sema_init(&isert_np->sem, 0);
2249 	mutex_init(&isert_np->mutex);
2250 	INIT_LIST_HEAD(&isert_np->accepted);
2251 	INIT_LIST_HEAD(&isert_np->pending);
2252 	isert_np->np = np;
2253 
2254 	/*
2255 	 * Setup the np->np_sockaddr from the passed sockaddr setup
2256 	 * in iscsi_target_configfs.c code..
2257 	 */
2258 	memcpy(&np->np_sockaddr, ksockaddr,
2259 	       sizeof(struct sockaddr_storage));
2260 
2261 	isert_lid = isert_setup_id(isert_np);
2262 	if (IS_ERR(isert_lid)) {
2263 		ret = PTR_ERR(isert_lid);
2264 		goto out;
2265 	}
2266 
2267 	isert_np->cm_id = isert_lid;
2268 	np->np_context = isert_np;
2269 
2270 	return 0;
2271 
2272 out:
2273 	kfree(isert_np);
2274 
2275 	return ret;
2276 }
2277 
2278 static int
2279 isert_rdma_accept(struct isert_conn *isert_conn)
2280 {
2281 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
2282 	struct rdma_conn_param cp;
2283 	int ret;
2284 	struct iser_cm_hdr rsp_hdr;
2285 
2286 	memset(&cp, 0, sizeof(struct rdma_conn_param));
2287 	cp.initiator_depth = isert_conn->initiator_depth;
2288 	cp.retry_count = 7;
2289 	cp.rnr_retry_count = 7;
2290 
2291 	memset(&rsp_hdr, 0, sizeof(rsp_hdr));
2292 	rsp_hdr.flags = ISERT_ZBVA_NOT_USED;
2293 	if (!isert_conn->snd_w_inv)
2294 		rsp_hdr.flags = rsp_hdr.flags | ISERT_SEND_W_INV_NOT_USED;
2295 	cp.private_data = (void *)&rsp_hdr;
2296 	cp.private_data_len = sizeof(rsp_hdr);
2297 
2298 	ret = rdma_accept(cm_id, &cp);
2299 	if (ret) {
2300 		isert_err("rdma_accept() failed with: %d\n", ret);
2301 		return ret;
2302 	}
2303 
2304 	return 0;
2305 }
2306 
2307 static int
2308 isert_get_login_rx(struct iscsi_conn *conn, struct iscsi_login *login)
2309 {
2310 	struct isert_conn *isert_conn = conn->context;
2311 	int ret;
2312 
2313 	isert_info("before login_req comp conn: %p\n", isert_conn);
2314 	ret = wait_for_completion_interruptible(&isert_conn->login_req_comp);
2315 	if (ret) {
2316 		isert_err("isert_conn %p interrupted before got login req\n",
2317 			  isert_conn);
2318 		return ret;
2319 	}
2320 	reinit_completion(&isert_conn->login_req_comp);
2321 
2322 	/*
2323 	 * For login requests after the first PDU, isert_rx_login_req() will
2324 	 * kick schedule_delayed_work(&conn->login_work) as the packet is
2325 	 * received, which turns this callback from iscsi_target_do_login_rx()
2326 	 * into a NOP.
2327 	 */
2328 	if (!login->first_request)
2329 		return 0;
2330 
2331 	isert_rx_login_req(isert_conn);
2332 
2333 	isert_info("before login_comp conn: %p\n", conn);
2334 	ret = wait_for_completion_interruptible(&isert_conn->login_comp);
2335 	if (ret)
2336 		return ret;
2337 
2338 	isert_info("processing login->req: %p\n", login->req);
2339 
2340 	return 0;
2341 }
2342 
2343 static void
2344 isert_set_conn_info(struct iscsi_np *np, struct iscsi_conn *conn,
2345 		    struct isert_conn *isert_conn)
2346 {
2347 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
2348 	struct rdma_route *cm_route = &cm_id->route;
2349 
2350 	conn->login_family = np->np_sockaddr.ss_family;
2351 
2352 	conn->login_sockaddr = cm_route->addr.dst_addr;
2353 	conn->local_sockaddr = cm_route->addr.src_addr;
2354 }
2355 
2356 static int
2357 isert_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
2358 {
2359 	struct isert_np *isert_np = np->np_context;
2360 	struct isert_conn *isert_conn;
2361 	int ret;
2362 
2363 accept_wait:
2364 	ret = down_interruptible(&isert_np->sem);
2365 	if (ret)
2366 		return -ENODEV;
2367 
2368 	spin_lock_bh(&np->np_thread_lock);
2369 	if (np->np_thread_state >= ISCSI_NP_THREAD_RESET) {
2370 		spin_unlock_bh(&np->np_thread_lock);
2371 		isert_dbg("np_thread_state %d\n",
2372 			 np->np_thread_state);
2373 		/**
2374 		 * No point in stalling here when np_thread
2375 		 * is in state RESET/SHUTDOWN/EXIT - bail
2376 		 **/
2377 		return -ENODEV;
2378 	}
2379 	spin_unlock_bh(&np->np_thread_lock);
2380 
2381 	mutex_lock(&isert_np->mutex);
2382 	if (list_empty(&isert_np->pending)) {
2383 		mutex_unlock(&isert_np->mutex);
2384 		goto accept_wait;
2385 	}
2386 	isert_conn = list_first_entry(&isert_np->pending,
2387 			struct isert_conn, node);
2388 	list_del_init(&isert_conn->node);
2389 	mutex_unlock(&isert_np->mutex);
2390 
2391 	conn->context = isert_conn;
2392 	isert_conn->conn = conn;
2393 	isert_conn->state = ISER_CONN_BOUND;
2394 
2395 	isert_set_conn_info(np, conn, isert_conn);
2396 
2397 	isert_dbg("Processing isert_conn: %p\n", isert_conn);
2398 
2399 	return 0;
2400 }
2401 
2402 static void
2403 isert_free_np(struct iscsi_np *np)
2404 {
2405 	struct isert_np *isert_np = np->np_context;
2406 	struct isert_conn *isert_conn, *n;
2407 
2408 	if (isert_np->cm_id)
2409 		rdma_destroy_id(isert_np->cm_id);
2410 
2411 	/*
2412 	 * FIXME: At this point we don't have a good way to insure
2413 	 * that at this point we don't have hanging connections that
2414 	 * completed RDMA establishment but didn't start iscsi login
2415 	 * process. So work-around this by cleaning up what ever piled
2416 	 * up in accepted and pending lists.
2417 	 */
2418 	mutex_lock(&isert_np->mutex);
2419 	if (!list_empty(&isert_np->pending)) {
2420 		isert_info("Still have isert pending connections\n");
2421 		list_for_each_entry_safe(isert_conn, n,
2422 					 &isert_np->pending,
2423 					 node) {
2424 			isert_info("cleaning isert_conn %p state (%d)\n",
2425 				   isert_conn, isert_conn->state);
2426 			isert_connect_release(isert_conn);
2427 		}
2428 	}
2429 
2430 	if (!list_empty(&isert_np->accepted)) {
2431 		isert_info("Still have isert accepted connections\n");
2432 		list_for_each_entry_safe(isert_conn, n,
2433 					 &isert_np->accepted,
2434 					 node) {
2435 			isert_info("cleaning isert_conn %p state (%d)\n",
2436 				   isert_conn, isert_conn->state);
2437 			isert_connect_release(isert_conn);
2438 		}
2439 	}
2440 	mutex_unlock(&isert_np->mutex);
2441 
2442 	np->np_context = NULL;
2443 	kfree(isert_np);
2444 }
2445 
2446 static void isert_release_work(struct work_struct *work)
2447 {
2448 	struct isert_conn *isert_conn = container_of(work,
2449 						     struct isert_conn,
2450 						     release_work);
2451 
2452 	isert_info("Starting release conn %p\n", isert_conn);
2453 
2454 	mutex_lock(&isert_conn->mutex);
2455 	isert_conn->state = ISER_CONN_DOWN;
2456 	mutex_unlock(&isert_conn->mutex);
2457 
2458 	isert_info("Destroying conn %p\n", isert_conn);
2459 	isert_put_conn(isert_conn);
2460 }
2461 
2462 static void
2463 isert_wait4logout(struct isert_conn *isert_conn)
2464 {
2465 	struct iscsi_conn *conn = isert_conn->conn;
2466 
2467 	isert_info("conn %p\n", isert_conn);
2468 
2469 	if (isert_conn->logout_posted) {
2470 		isert_info("conn %p wait for conn_logout_comp\n", isert_conn);
2471 		wait_for_completion_timeout(&conn->conn_logout_comp,
2472 					    SECONDS_FOR_LOGOUT_COMP * HZ);
2473 	}
2474 }
2475 
2476 static void
2477 isert_wait4cmds(struct iscsi_conn *conn)
2478 {
2479 	isert_info("iscsi_conn %p\n", conn);
2480 
2481 	if (conn->sess) {
2482 		target_sess_cmd_list_set_waiting(conn->sess->se_sess);
2483 		target_wait_for_sess_cmds(conn->sess->se_sess);
2484 	}
2485 }
2486 
2487 /**
2488  * isert_put_unsol_pending_cmds() - Drop commands waiting for
2489  *     unsolicitate dataout
2490  * @conn:    iscsi connection
2491  *
2492  * We might still have commands that are waiting for unsolicited
2493  * dataouts messages. We must put the extra reference on those
2494  * before blocking on the target_wait_for_session_cmds
2495  */
2496 static void
2497 isert_put_unsol_pending_cmds(struct iscsi_conn *conn)
2498 {
2499 	struct iscsi_cmd *cmd, *tmp;
2500 	static LIST_HEAD(drop_cmd_list);
2501 
2502 	spin_lock_bh(&conn->cmd_lock);
2503 	list_for_each_entry_safe(cmd, tmp, &conn->conn_cmd_list, i_conn_node) {
2504 		if ((cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA) &&
2505 		    (cmd->write_data_done < conn->sess->sess_ops->FirstBurstLength) &&
2506 		    (cmd->write_data_done < cmd->se_cmd.data_length))
2507 			list_move_tail(&cmd->i_conn_node, &drop_cmd_list);
2508 	}
2509 	spin_unlock_bh(&conn->cmd_lock);
2510 
2511 	list_for_each_entry_safe(cmd, tmp, &drop_cmd_list, i_conn_node) {
2512 		list_del_init(&cmd->i_conn_node);
2513 		if (cmd->i_state != ISTATE_REMOVE) {
2514 			struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2515 
2516 			isert_info("conn %p dropping cmd %p\n", conn, cmd);
2517 			isert_put_cmd(isert_cmd, true);
2518 		}
2519 	}
2520 }
2521 
2522 static void isert_wait_conn(struct iscsi_conn *conn)
2523 {
2524 	struct isert_conn *isert_conn = conn->context;
2525 
2526 	isert_info("Starting conn %p\n", isert_conn);
2527 
2528 	mutex_lock(&isert_conn->mutex);
2529 	isert_conn_terminate(isert_conn);
2530 	mutex_unlock(&isert_conn->mutex);
2531 
2532 	ib_drain_qp(isert_conn->qp);
2533 	isert_put_unsol_pending_cmds(conn);
2534 	isert_wait4cmds(conn);
2535 	isert_wait4logout(isert_conn);
2536 
2537 	queue_work(isert_release_wq, &isert_conn->release_work);
2538 }
2539 
2540 static void isert_free_conn(struct iscsi_conn *conn)
2541 {
2542 	struct isert_conn *isert_conn = conn->context;
2543 
2544 	ib_drain_qp(isert_conn->qp);
2545 	isert_put_conn(isert_conn);
2546 }
2547 
2548 static void isert_get_rx_pdu(struct iscsi_conn *conn)
2549 {
2550 	struct completion comp;
2551 
2552 	init_completion(&comp);
2553 
2554 	wait_for_completion_interruptible(&comp);
2555 }
2556 
2557 static struct iscsit_transport iser_target_transport = {
2558 	.name			= "IB/iSER",
2559 	.transport_type		= ISCSI_INFINIBAND,
2560 	.rdma_shutdown		= true,
2561 	.priv_size		= sizeof(struct isert_cmd),
2562 	.owner			= THIS_MODULE,
2563 	.iscsit_setup_np	= isert_setup_np,
2564 	.iscsit_accept_np	= isert_accept_np,
2565 	.iscsit_free_np		= isert_free_np,
2566 	.iscsit_wait_conn	= isert_wait_conn,
2567 	.iscsit_free_conn	= isert_free_conn,
2568 	.iscsit_get_login_rx	= isert_get_login_rx,
2569 	.iscsit_put_login_tx	= isert_put_login_tx,
2570 	.iscsit_immediate_queue	= isert_immediate_queue,
2571 	.iscsit_response_queue	= isert_response_queue,
2572 	.iscsit_get_dataout	= isert_get_dataout,
2573 	.iscsit_queue_data_in	= isert_put_datain,
2574 	.iscsit_queue_status	= isert_put_response,
2575 	.iscsit_aborted_task	= isert_aborted_task,
2576 	.iscsit_get_rx_pdu	= isert_get_rx_pdu,
2577 	.iscsit_get_sup_prot_ops = isert_get_sup_prot_ops,
2578 };
2579 
2580 static int __init isert_init(void)
2581 {
2582 	int ret;
2583 
2584 	isert_comp_wq = alloc_workqueue("isert_comp_wq",
2585 					WQ_UNBOUND | WQ_HIGHPRI, 0);
2586 	if (!isert_comp_wq) {
2587 		isert_err("Unable to allocate isert_comp_wq\n");
2588 		return -ENOMEM;
2589 	}
2590 
2591 	isert_release_wq = alloc_workqueue("isert_release_wq", WQ_UNBOUND,
2592 					WQ_UNBOUND_MAX_ACTIVE);
2593 	if (!isert_release_wq) {
2594 		isert_err("Unable to allocate isert_release_wq\n");
2595 		ret = -ENOMEM;
2596 		goto destroy_comp_wq;
2597 	}
2598 
2599 	iscsit_register_transport(&iser_target_transport);
2600 	isert_info("iSER_TARGET[0] - Loaded iser_target_transport\n");
2601 
2602 	return 0;
2603 
2604 destroy_comp_wq:
2605 	destroy_workqueue(isert_comp_wq);
2606 
2607 	return ret;
2608 }
2609 
2610 static void __exit isert_exit(void)
2611 {
2612 	flush_scheduled_work();
2613 	destroy_workqueue(isert_release_wq);
2614 	destroy_workqueue(isert_comp_wq);
2615 	iscsit_unregister_transport(&iser_target_transport);
2616 	isert_info("iSER_TARGET[0] - Released iser_target_transport\n");
2617 }
2618 
2619 MODULE_DESCRIPTION("iSER-Target for mainline target infrastructure");
2620 MODULE_AUTHOR("nab@Linux-iSCSI.org");
2621 MODULE_LICENSE("GPL");
2622 
2623 module_init(isert_init);
2624 module_exit(isert_exit);
2625