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, rx_desc->buf,
144 					ISER_RX_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 + isert_get_hdr_offset(rx_desc);
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_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_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_desc->dma_addr,
303 			    ISER_RX_SIZE, DMA_FROM_DEVICE);
304 	kfree(isert_conn->login_desc);
305 }
306 
307 static int
308 isert_alloc_login_buf(struct isert_conn *isert_conn,
309 		      struct ib_device *ib_dev)
310 {
311 	int ret;
312 
313 	isert_conn->login_desc = kzalloc(sizeof(*isert_conn->login_desc),
314 			GFP_KERNEL);
315 	if (!isert_conn->login_desc)
316 		return -ENOMEM;
317 
318 	isert_conn->login_desc->dma_addr = ib_dma_map_single(ib_dev,
319 				isert_conn->login_desc->buf,
320 				ISER_RX_SIZE, DMA_FROM_DEVICE);
321 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_desc->dma_addr);
322 	if (ret) {
323 		isert_err("login_desc dma mapping error: %d\n", ret);
324 		isert_conn->login_desc->dma_addr = 0;
325 		goto out_free_login_desc;
326 	}
327 
328 	isert_conn->login_rsp_buf = kzalloc(ISER_RX_PAYLOAD_SIZE, GFP_KERNEL);
329 	if (!isert_conn->login_rsp_buf) {
330 		ret = -ENOMEM;
331 		goto out_unmap_login_desc;
332 	}
333 
334 	isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
335 					isert_conn->login_rsp_buf,
336 					ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
337 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
338 	if (ret) {
339 		isert_err("login_rsp_dma mapping error: %d\n", ret);
340 		isert_conn->login_rsp_dma = 0;
341 		goto out_free_login_rsp_buf;
342 	}
343 
344 	return 0;
345 
346 out_free_login_rsp_buf:
347 	kfree(isert_conn->login_rsp_buf);
348 out_unmap_login_desc:
349 	ib_dma_unmap_single(ib_dev, isert_conn->login_desc->dma_addr,
350 			    ISER_RX_SIZE, DMA_FROM_DEVICE);
351 out_free_login_desc:
352 	kfree(isert_conn->login_desc);
353 	return ret;
354 }
355 
356 static void
357 isert_set_nego_params(struct isert_conn *isert_conn,
358 		      struct rdma_conn_param *param)
359 {
360 	struct ib_device_attr *attr = &isert_conn->device->ib_device->attrs;
361 
362 	/* Set max inflight RDMA READ requests */
363 	isert_conn->initiator_depth = min_t(u8, param->initiator_depth,
364 				attr->max_qp_init_rd_atom);
365 	isert_dbg("Using initiator_depth: %u\n", isert_conn->initiator_depth);
366 
367 	if (param->private_data) {
368 		u8 flags = *(u8 *)param->private_data;
369 
370 		/*
371 		 * use remote invalidation if the both initiator
372 		 * and the HCA support it
373 		 */
374 		isert_conn->snd_w_inv = !(flags & ISER_SEND_W_INV_NOT_SUP) &&
375 					  (attr->device_cap_flags &
376 					   IB_DEVICE_MEM_MGT_EXTENSIONS);
377 		if (isert_conn->snd_w_inv)
378 			isert_info("Using remote invalidation\n");
379 	}
380 }
381 
382 static void
383 isert_destroy_qp(struct isert_conn *isert_conn)
384 {
385 	ib_destroy_qp(isert_conn->qp);
386 	ib_cq_pool_put(isert_conn->cq, isert_conn->cq_size);
387 }
388 
389 static int
390 isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
391 {
392 	struct isert_np *isert_np = cma_id->context;
393 	struct iscsi_np *np = isert_np->np;
394 	struct isert_conn *isert_conn;
395 	struct isert_device *device;
396 	int ret = 0;
397 
398 	spin_lock_bh(&np->np_thread_lock);
399 	if (!np->enabled) {
400 		spin_unlock_bh(&np->np_thread_lock);
401 		isert_dbg("iscsi_np is not enabled, reject connect request\n");
402 		return rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
403 	}
404 	spin_unlock_bh(&np->np_thread_lock);
405 
406 	isert_dbg("cma_id: %p, portal: %p\n",
407 		 cma_id, cma_id->context);
408 
409 	isert_conn = kzalloc(sizeof(struct isert_conn), GFP_KERNEL);
410 	if (!isert_conn)
411 		return -ENOMEM;
412 
413 	isert_init_conn(isert_conn);
414 	isert_conn->cm_id = cma_id;
415 
416 	ret = isert_alloc_login_buf(isert_conn, cma_id->device);
417 	if (ret)
418 		goto out;
419 
420 	device = isert_device_get(cma_id);
421 	if (IS_ERR(device)) {
422 		ret = PTR_ERR(device);
423 		goto out_rsp_dma_map;
424 	}
425 	isert_conn->device = device;
426 
427 	isert_set_nego_params(isert_conn, &event->param.conn);
428 
429 	isert_conn->qp = isert_create_qp(isert_conn, cma_id);
430 	if (IS_ERR(isert_conn->qp)) {
431 		ret = PTR_ERR(isert_conn->qp);
432 		goto out_conn_dev;
433 	}
434 
435 	ret = isert_login_post_recv(isert_conn);
436 	if (ret)
437 		goto out_destroy_qp;
438 
439 	ret = isert_rdma_accept(isert_conn);
440 	if (ret)
441 		goto out_destroy_qp;
442 
443 	mutex_lock(&isert_np->mutex);
444 	list_add_tail(&isert_conn->node, &isert_np->accepted);
445 	mutex_unlock(&isert_np->mutex);
446 
447 	return 0;
448 
449 out_destroy_qp:
450 	isert_destroy_qp(isert_conn);
451 out_conn_dev:
452 	isert_device_put(device);
453 out_rsp_dma_map:
454 	isert_free_login_buf(isert_conn);
455 out:
456 	kfree(isert_conn);
457 	rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
458 	return ret;
459 }
460 
461 static void
462 isert_connect_release(struct isert_conn *isert_conn)
463 {
464 	struct isert_device *device = isert_conn->device;
465 
466 	isert_dbg("conn %p\n", isert_conn);
467 
468 	BUG_ON(!device);
469 
470 	isert_free_rx_descriptors(isert_conn);
471 	if (isert_conn->cm_id &&
472 	    !isert_conn->dev_removed)
473 		rdma_destroy_id(isert_conn->cm_id);
474 
475 	if (isert_conn->qp)
476 		isert_destroy_qp(isert_conn);
477 
478 	if (isert_conn->login_desc)
479 		isert_free_login_buf(isert_conn);
480 
481 	isert_device_put(device);
482 
483 	if (isert_conn->dev_removed)
484 		wake_up_interruptible(&isert_conn->rem_wait);
485 	else
486 		kfree(isert_conn);
487 }
488 
489 static void
490 isert_connected_handler(struct rdma_cm_id *cma_id)
491 {
492 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
493 	struct isert_np *isert_np = cma_id->context;
494 
495 	isert_info("conn %p\n", isert_conn);
496 
497 	mutex_lock(&isert_conn->mutex);
498 	isert_conn->state = ISER_CONN_UP;
499 	kref_get(&isert_conn->kref);
500 	mutex_unlock(&isert_conn->mutex);
501 
502 	mutex_lock(&isert_np->mutex);
503 	list_move_tail(&isert_conn->node, &isert_np->pending);
504 	mutex_unlock(&isert_np->mutex);
505 
506 	isert_info("np %p: Allow accept_np to continue\n", isert_np);
507 	up(&isert_np->sem);
508 }
509 
510 static void
511 isert_release_kref(struct kref *kref)
512 {
513 	struct isert_conn *isert_conn = container_of(kref,
514 				struct isert_conn, kref);
515 
516 	isert_info("conn %p final kref %s/%d\n", isert_conn, current->comm,
517 		   current->pid);
518 
519 	isert_connect_release(isert_conn);
520 }
521 
522 static void
523 isert_put_conn(struct isert_conn *isert_conn)
524 {
525 	kref_put(&isert_conn->kref, isert_release_kref);
526 }
527 
528 static void
529 isert_handle_unbound_conn(struct isert_conn *isert_conn)
530 {
531 	struct isert_np *isert_np = isert_conn->cm_id->context;
532 
533 	mutex_lock(&isert_np->mutex);
534 	if (!list_empty(&isert_conn->node)) {
535 		/*
536 		 * This means iscsi doesn't know this connection
537 		 * so schedule a cleanup ourselves
538 		 */
539 		list_del_init(&isert_conn->node);
540 		isert_put_conn(isert_conn);
541 		queue_work(isert_release_wq, &isert_conn->release_work);
542 	}
543 	mutex_unlock(&isert_np->mutex);
544 }
545 
546 /**
547  * isert_conn_terminate() - Initiate connection termination
548  * @isert_conn: isert connection struct
549  *
550  * Notes:
551  * In case the connection state is BOUND, move state
552  * to TEMINATING and start teardown sequence (rdma_disconnect).
553  * In case the connection state is UP, complete flush as well.
554  *
555  * This routine must be called with mutex held. Thus it is
556  * safe to call multiple times.
557  */
558 static void
559 isert_conn_terminate(struct isert_conn *isert_conn)
560 {
561 	int err;
562 
563 	if (isert_conn->state >= ISER_CONN_TERMINATING)
564 		return;
565 
566 	isert_info("Terminating conn %p state %d\n",
567 		   isert_conn, isert_conn->state);
568 	isert_conn->state = ISER_CONN_TERMINATING;
569 	err = rdma_disconnect(isert_conn->cm_id);
570 	if (err)
571 		isert_warn("Failed rdma_disconnect isert_conn %p\n",
572 			   isert_conn);
573 }
574 
575 static int
576 isert_np_cma_handler(struct isert_np *isert_np,
577 		     enum rdma_cm_event_type event)
578 {
579 	isert_dbg("%s (%d): isert np %p\n",
580 		  rdma_event_msg(event), event, isert_np);
581 
582 	switch (event) {
583 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
584 		isert_np->cm_id = NULL;
585 		break;
586 	case RDMA_CM_EVENT_ADDR_CHANGE:
587 		isert_np->cm_id = isert_setup_id(isert_np);
588 		if (IS_ERR(isert_np->cm_id)) {
589 			isert_err("isert np %p setup id failed: %ld\n",
590 				  isert_np, PTR_ERR(isert_np->cm_id));
591 			isert_np->cm_id = NULL;
592 		}
593 		break;
594 	default:
595 		isert_err("isert np %p Unexpected event %d\n",
596 			  isert_np, event);
597 	}
598 
599 	return -1;
600 }
601 
602 static int
603 isert_disconnected_handler(struct rdma_cm_id *cma_id,
604 			   enum rdma_cm_event_type event)
605 {
606 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
607 
608 	mutex_lock(&isert_conn->mutex);
609 	switch (isert_conn->state) {
610 	case ISER_CONN_TERMINATING:
611 		break;
612 	case ISER_CONN_UP:
613 		isert_conn_terminate(isert_conn);
614 		ib_drain_qp(isert_conn->qp);
615 		isert_handle_unbound_conn(isert_conn);
616 		break;
617 	case ISER_CONN_BOUND:
618 	case ISER_CONN_FULL_FEATURE: /* FALLTHRU */
619 		iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
620 		break;
621 	default:
622 		isert_warn("conn %p terminating in state %d\n",
623 			   isert_conn, isert_conn->state);
624 	}
625 	mutex_unlock(&isert_conn->mutex);
626 
627 	return 0;
628 }
629 
630 static int
631 isert_connect_error(struct rdma_cm_id *cma_id)
632 {
633 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
634 
635 	ib_drain_qp(isert_conn->qp);
636 	list_del_init(&isert_conn->node);
637 	isert_conn->cm_id = NULL;
638 	isert_put_conn(isert_conn);
639 
640 	return -1;
641 }
642 
643 static int
644 isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
645 {
646 	struct isert_np *isert_np = cma_id->context;
647 	struct isert_conn *isert_conn;
648 	int ret = 0;
649 
650 	isert_info("%s (%d): status %d id %p np %p\n",
651 		   rdma_event_msg(event->event), event->event,
652 		   event->status, cma_id, cma_id->context);
653 
654 	if (isert_np->cm_id == cma_id)
655 		return isert_np_cma_handler(cma_id->context, event->event);
656 
657 	switch (event->event) {
658 	case RDMA_CM_EVENT_CONNECT_REQUEST:
659 		ret = isert_connect_request(cma_id, event);
660 		if (ret)
661 			isert_err("failed handle connect request %d\n", ret);
662 		break;
663 	case RDMA_CM_EVENT_ESTABLISHED:
664 		isert_connected_handler(cma_id);
665 		break;
666 	case RDMA_CM_EVENT_ADDR_CHANGE:
667 	case RDMA_CM_EVENT_DISCONNECTED:
668 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:  /* FALLTHRU */
669 		ret = isert_disconnected_handler(cma_id, event->event);
670 		break;
671 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
672 		isert_conn = cma_id->qp->qp_context;
673 		isert_conn->dev_removed = true;
674 		isert_disconnected_handler(cma_id, event->event);
675 		wait_event_interruptible(isert_conn->rem_wait,
676 					 isert_conn->state == ISER_CONN_DOWN);
677 		kfree(isert_conn);
678 		/*
679 		 * return non-zero from the callback to destroy
680 		 * the rdma cm id
681 		 */
682 		return 1;
683 	case RDMA_CM_EVENT_REJECTED:
684 		isert_info("Connection rejected: %s\n",
685 			   rdma_reject_msg(cma_id, event->status));
686 		fallthrough;
687 	case RDMA_CM_EVENT_UNREACHABLE:
688 	case RDMA_CM_EVENT_CONNECT_ERROR:
689 		ret = isert_connect_error(cma_id);
690 		break;
691 	default:
692 		isert_err("Unhandled RDMA CMA event: %d\n", event->event);
693 		break;
694 	}
695 
696 	return ret;
697 }
698 
699 static int
700 isert_post_recvm(struct isert_conn *isert_conn, u32 count)
701 {
702 	struct ib_recv_wr *rx_wr;
703 	int i, ret;
704 	struct iser_rx_desc *rx_desc;
705 
706 	for (rx_wr = isert_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
707 		rx_desc = &isert_conn->rx_descs[i];
708 
709 		rx_wr->wr_cqe = &rx_desc->rx_cqe;
710 		rx_wr->sg_list = &rx_desc->rx_sg;
711 		rx_wr->num_sge = 1;
712 		rx_wr->next = rx_wr + 1;
713 		rx_desc->in_use = false;
714 	}
715 	rx_wr--;
716 	rx_wr->next = NULL; /* mark end of work requests list */
717 
718 	ret = ib_post_recv(isert_conn->qp, isert_conn->rx_wr, NULL);
719 	if (ret)
720 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
721 
722 	return ret;
723 }
724 
725 static int
726 isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
727 {
728 	struct ib_recv_wr rx_wr;
729 	int ret;
730 
731 	if (!rx_desc->in_use) {
732 		/*
733 		 * if the descriptor is not in-use we already reposted it
734 		 * for recv, so just silently return
735 		 */
736 		return 0;
737 	}
738 
739 	rx_desc->in_use = false;
740 	rx_wr.wr_cqe = &rx_desc->rx_cqe;
741 	rx_wr.sg_list = &rx_desc->rx_sg;
742 	rx_wr.num_sge = 1;
743 	rx_wr.next = NULL;
744 
745 	ret = ib_post_recv(isert_conn->qp, &rx_wr, NULL);
746 	if (ret)
747 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
748 
749 	return ret;
750 }
751 
752 static int
753 isert_login_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
754 {
755 	struct ib_device *ib_dev = isert_conn->cm_id->device;
756 	struct ib_send_wr send_wr;
757 	int ret;
758 
759 	ib_dma_sync_single_for_device(ib_dev, tx_desc->dma_addr,
760 				      ISER_HEADERS_LEN, DMA_TO_DEVICE);
761 
762 	tx_desc->tx_cqe.done = isert_login_send_done;
763 
764 	send_wr.next	= NULL;
765 	send_wr.wr_cqe	= &tx_desc->tx_cqe;
766 	send_wr.sg_list	= tx_desc->tx_sg;
767 	send_wr.num_sge	= tx_desc->num_sge;
768 	send_wr.opcode	= IB_WR_SEND;
769 	send_wr.send_flags = IB_SEND_SIGNALED;
770 
771 	ret = ib_post_send(isert_conn->qp, &send_wr, NULL);
772 	if (ret)
773 		isert_err("ib_post_send() failed, ret: %d\n", ret);
774 
775 	return ret;
776 }
777 
778 static void
779 __isert_create_send_desc(struct isert_device *device,
780 			 struct iser_tx_desc *tx_desc)
781 {
782 
783 	memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl));
784 	tx_desc->iser_header.flags = ISCSI_CTRL;
785 
786 	tx_desc->num_sge = 1;
787 
788 	if (tx_desc->tx_sg[0].lkey != device->pd->local_dma_lkey) {
789 		tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
790 		isert_dbg("tx_desc %p lkey mismatch, fixing\n", tx_desc);
791 	}
792 }
793 
794 static void
795 isert_create_send_desc(struct isert_conn *isert_conn,
796 		       struct isert_cmd *isert_cmd,
797 		       struct iser_tx_desc *tx_desc)
798 {
799 	struct isert_device *device = isert_conn->device;
800 	struct ib_device *ib_dev = device->ib_device;
801 
802 	ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr,
803 				   ISER_HEADERS_LEN, DMA_TO_DEVICE);
804 
805 	__isert_create_send_desc(device, tx_desc);
806 }
807 
808 static int
809 isert_init_tx_hdrs(struct isert_conn *isert_conn,
810 		   struct iser_tx_desc *tx_desc)
811 {
812 	struct isert_device *device = isert_conn->device;
813 	struct ib_device *ib_dev = device->ib_device;
814 	u64 dma_addr;
815 
816 	dma_addr = ib_dma_map_single(ib_dev, (void *)tx_desc,
817 			ISER_HEADERS_LEN, DMA_TO_DEVICE);
818 	if (ib_dma_mapping_error(ib_dev, dma_addr)) {
819 		isert_err("ib_dma_mapping_error() failed\n");
820 		return -ENOMEM;
821 	}
822 
823 	tx_desc->dma_addr = dma_addr;
824 	tx_desc->tx_sg[0].addr	= tx_desc->dma_addr;
825 	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
826 	tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
827 
828 	isert_dbg("Setup tx_sg[0].addr: 0x%llx length: %u lkey: 0x%x\n",
829 		  tx_desc->tx_sg[0].addr, tx_desc->tx_sg[0].length,
830 		  tx_desc->tx_sg[0].lkey);
831 
832 	return 0;
833 }
834 
835 static void
836 isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
837 		   struct ib_send_wr *send_wr)
838 {
839 	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
840 
841 	tx_desc->tx_cqe.done = isert_send_done;
842 	send_wr->wr_cqe = &tx_desc->tx_cqe;
843 
844 	if (isert_conn->snd_w_inv && isert_cmd->inv_rkey) {
845 		send_wr->opcode  = IB_WR_SEND_WITH_INV;
846 		send_wr->ex.invalidate_rkey = isert_cmd->inv_rkey;
847 	} else {
848 		send_wr->opcode = IB_WR_SEND;
849 	}
850 
851 	send_wr->sg_list = &tx_desc->tx_sg[0];
852 	send_wr->num_sge = isert_cmd->tx_desc.num_sge;
853 	send_wr->send_flags = IB_SEND_SIGNALED;
854 }
855 
856 static int
857 isert_login_post_recv(struct isert_conn *isert_conn)
858 {
859 	struct ib_recv_wr rx_wr;
860 	struct ib_sge sge;
861 	int ret;
862 
863 	memset(&sge, 0, sizeof(struct ib_sge));
864 	sge.addr = isert_conn->login_desc->dma_addr +
865 		isert_get_hdr_offset(isert_conn->login_desc);
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_desc->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_desc->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_desc;
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 *)isert_get_iscsi_hdr(rx_desc);
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], isert_get_iscsi_hdr(rx_desc), 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, isert_get_data(rx_desc), 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 				    isert_get_data(rx_desc), 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, isert_get_data(rx_desc),
1062 				imm_data_len);
1063 		isert_dbg("Transfer Immediate imm_data_len: %d\n",
1064 			  imm_data_len);
1065 	}
1066 
1067 	cmd->write_data_done += imm_data_len;
1068 
1069 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
1070 		spin_lock_bh(&cmd->istate_lock);
1071 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1072 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1073 		spin_unlock_bh(&cmd->istate_lock);
1074 	}
1075 
1076 sequence_cmd:
1077 	rc = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1078 
1079 	if (!rc && dump_payload == false && unsol_data)
1080 		iscsit_set_unsolicited_dataout(cmd);
1081 	else if (dump_payload && imm_data)
1082 		target_put_sess_cmd(&cmd->se_cmd);
1083 
1084 	return 0;
1085 }
1086 
1087 static int
1088 isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
1089 			   struct iser_rx_desc *rx_desc, unsigned char *buf)
1090 {
1091 	struct scatterlist *sg_start;
1092 	struct iscsi_conn *conn = isert_conn->conn;
1093 	struct iscsi_cmd *cmd = NULL;
1094 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1095 	u32 unsol_data_len = ntoh24(hdr->dlength);
1096 	int rc, sg_nents, sg_off, page_off;
1097 
1098 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1099 	if (rc < 0)
1100 		return rc;
1101 	else if (!cmd)
1102 		return 0;
1103 	/*
1104 	 * FIXME: Unexpected unsolicited_data out
1105 	 */
1106 	if (!cmd->unsolicited_data) {
1107 		isert_err("Received unexpected solicited data payload\n");
1108 		dump_stack();
1109 		return -1;
1110 	}
1111 
1112 	isert_dbg("Unsolicited DataOut unsol_data_len: %u, "
1113 		  "write_data_done: %u, data_length: %u\n",
1114 		  unsol_data_len,  cmd->write_data_done,
1115 		  cmd->se_cmd.data_length);
1116 
1117 	sg_off = cmd->write_data_done / PAGE_SIZE;
1118 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
1119 	sg_nents = max(1UL, DIV_ROUND_UP(unsol_data_len, PAGE_SIZE));
1120 	page_off = cmd->write_data_done % PAGE_SIZE;
1121 	/*
1122 	 * FIXME: Non page-aligned unsolicited_data out
1123 	 */
1124 	if (page_off) {
1125 		isert_err("unexpected non-page aligned data payload\n");
1126 		dump_stack();
1127 		return -1;
1128 	}
1129 	isert_dbg("Copying DataOut: sg_start: %p, sg_off: %u "
1130 		  "sg_nents: %u from %p %u\n", sg_start, sg_off,
1131 		  sg_nents, isert_get_data(rx_desc), unsol_data_len);
1132 
1133 	sg_copy_from_buffer(sg_start, sg_nents, isert_get_data(rx_desc),
1134 			    unsol_data_len);
1135 
1136 	rc = iscsit_check_dataout_payload(cmd, hdr, false);
1137 	if (rc < 0)
1138 		return rc;
1139 
1140 	/*
1141 	 * multiple data-outs on the same command can arrive -
1142 	 * so post the buffer before hand
1143 	 */
1144 	rc = isert_post_recv(isert_conn, rx_desc);
1145 	if (rc) {
1146 		isert_err("ib_post_recv failed with %d\n", rc);
1147 		return rc;
1148 	}
1149 	return 0;
1150 }
1151 
1152 static int
1153 isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1154 		     struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1155 		     unsigned char *buf)
1156 {
1157 	struct iscsi_conn *conn = isert_conn->conn;
1158 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1159 	int rc;
1160 
1161 	rc = iscsit_setup_nop_out(conn, cmd, hdr);
1162 	if (rc < 0)
1163 		return rc;
1164 	/*
1165 	 * FIXME: Add support for NOPOUT payload using unsolicited RDMA payload
1166 	 */
1167 
1168 	return iscsit_process_nop_out(conn, cmd, hdr);
1169 }
1170 
1171 static int
1172 isert_handle_text_cmd(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1173 		      struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1174 		      struct iscsi_text *hdr)
1175 {
1176 	struct iscsi_conn *conn = isert_conn->conn;
1177 	u32 payload_length = ntoh24(hdr->dlength);
1178 	int rc;
1179 	unsigned char *text_in = NULL;
1180 
1181 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
1182 	if (rc < 0)
1183 		return rc;
1184 
1185 	if (payload_length) {
1186 		text_in = kzalloc(payload_length, GFP_KERNEL);
1187 		if (!text_in)
1188 			return -ENOMEM;
1189 	}
1190 	cmd->text_in_ptr = text_in;
1191 
1192 	memcpy(cmd->text_in_ptr, isert_get_data(rx_desc), payload_length);
1193 
1194 	return iscsit_process_text_cmd(conn, cmd, hdr);
1195 }
1196 
1197 static int
1198 isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
1199 		uint32_t read_stag, uint64_t read_va,
1200 		uint32_t write_stag, uint64_t write_va)
1201 {
1202 	struct iscsi_hdr *hdr = isert_get_iscsi_hdr(rx_desc);
1203 	struct iscsi_conn *conn = isert_conn->conn;
1204 	struct iscsi_cmd *cmd;
1205 	struct isert_cmd *isert_cmd;
1206 	int ret = -EINVAL;
1207 	u8 opcode = (hdr->opcode & ISCSI_OPCODE_MASK);
1208 
1209 	if (conn->sess->sess_ops->SessionType &&
1210 	   (!(opcode & ISCSI_OP_TEXT) || !(opcode & ISCSI_OP_LOGOUT))) {
1211 		isert_err("Got illegal opcode: 0x%02x in SessionType=Discovery,"
1212 			  " ignoring\n", opcode);
1213 		return 0;
1214 	}
1215 
1216 	switch (opcode) {
1217 	case ISCSI_OP_SCSI_CMD:
1218 		cmd = isert_allocate_cmd(conn, rx_desc);
1219 		if (!cmd)
1220 			break;
1221 
1222 		isert_cmd = iscsit_priv_cmd(cmd);
1223 		isert_cmd->read_stag = read_stag;
1224 		isert_cmd->read_va = read_va;
1225 		isert_cmd->write_stag = write_stag;
1226 		isert_cmd->write_va = write_va;
1227 		isert_cmd->inv_rkey = read_stag ? read_stag : write_stag;
1228 
1229 		ret = isert_handle_scsi_cmd(isert_conn, isert_cmd, cmd,
1230 					rx_desc, (unsigned char *)hdr);
1231 		break;
1232 	case ISCSI_OP_NOOP_OUT:
1233 		cmd = isert_allocate_cmd(conn, rx_desc);
1234 		if (!cmd)
1235 			break;
1236 
1237 		isert_cmd = iscsit_priv_cmd(cmd);
1238 		ret = isert_handle_nop_out(isert_conn, isert_cmd, cmd,
1239 					   rx_desc, (unsigned char *)hdr);
1240 		break;
1241 	case ISCSI_OP_SCSI_DATA_OUT:
1242 		ret = isert_handle_iscsi_dataout(isert_conn, rx_desc,
1243 						(unsigned char *)hdr);
1244 		break;
1245 	case ISCSI_OP_SCSI_TMFUNC:
1246 		cmd = isert_allocate_cmd(conn, rx_desc);
1247 		if (!cmd)
1248 			break;
1249 
1250 		ret = iscsit_handle_task_mgt_cmd(conn, cmd,
1251 						(unsigned char *)hdr);
1252 		break;
1253 	case ISCSI_OP_LOGOUT:
1254 		cmd = isert_allocate_cmd(conn, rx_desc);
1255 		if (!cmd)
1256 			break;
1257 
1258 		ret = iscsit_handle_logout_cmd(conn, cmd, (unsigned char *)hdr);
1259 		break;
1260 	case ISCSI_OP_TEXT:
1261 		if (be32_to_cpu(hdr->ttt) != 0xFFFFFFFF)
1262 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
1263 		else
1264 			cmd = isert_allocate_cmd(conn, rx_desc);
1265 
1266 		if (!cmd)
1267 			break;
1268 
1269 		isert_cmd = iscsit_priv_cmd(cmd);
1270 		ret = isert_handle_text_cmd(isert_conn, isert_cmd, cmd,
1271 					    rx_desc, (struct iscsi_text *)hdr);
1272 		break;
1273 	default:
1274 		isert_err("Got unknown iSCSI OpCode: 0x%02x\n", opcode);
1275 		dump_stack();
1276 		break;
1277 	}
1278 
1279 	return ret;
1280 }
1281 
1282 static void
1283 isert_print_wc(struct ib_wc *wc, const char *type)
1284 {
1285 	if (wc->status != IB_WC_WR_FLUSH_ERR)
1286 		isert_err("%s failure: %s (%d) vend_err %x\n", type,
1287 			  ib_wc_status_msg(wc->status), wc->status,
1288 			  wc->vendor_err);
1289 	else
1290 		isert_dbg("%s failure: %s (%d)\n", type,
1291 			  ib_wc_status_msg(wc->status), wc->status);
1292 }
1293 
1294 static void
1295 isert_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1296 {
1297 	struct isert_conn *isert_conn = wc->qp->qp_context;
1298 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1299 	struct iser_rx_desc *rx_desc = cqe_to_rx_desc(wc->wr_cqe);
1300 	struct iscsi_hdr *hdr = isert_get_iscsi_hdr(rx_desc);
1301 	struct iser_ctrl *iser_ctrl = isert_get_iser_hdr(rx_desc);
1302 	uint64_t read_va = 0, write_va = 0;
1303 	uint32_t read_stag = 0, write_stag = 0;
1304 
1305 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1306 		isert_print_wc(wc, "recv");
1307 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1308 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1309 		return;
1310 	}
1311 
1312 	rx_desc->in_use = true;
1313 
1314 	ib_dma_sync_single_for_cpu(ib_dev, rx_desc->dma_addr,
1315 			ISER_RX_SIZE, DMA_FROM_DEVICE);
1316 
1317 	isert_dbg("DMA: 0x%llx, iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n",
1318 		 rx_desc->dma_addr, hdr->opcode, hdr->itt, hdr->flags,
1319 		 (int)(wc->byte_len - ISER_HEADERS_LEN));
1320 
1321 	switch (iser_ctrl->flags & 0xF0) {
1322 	case ISCSI_CTRL:
1323 		if (iser_ctrl->flags & ISER_RSV) {
1324 			read_stag = be32_to_cpu(iser_ctrl->read_stag);
1325 			read_va = be64_to_cpu(iser_ctrl->read_va);
1326 			isert_dbg("ISER_RSV: read_stag: 0x%x read_va: 0x%llx\n",
1327 				  read_stag, (unsigned long long)read_va);
1328 		}
1329 		if (iser_ctrl->flags & ISER_WSV) {
1330 			write_stag = be32_to_cpu(iser_ctrl->write_stag);
1331 			write_va = be64_to_cpu(iser_ctrl->write_va);
1332 			isert_dbg("ISER_WSV: write_stag: 0x%x write_va: 0x%llx\n",
1333 				  write_stag, (unsigned long long)write_va);
1334 		}
1335 
1336 		isert_dbg("ISER ISCSI_CTRL PDU\n");
1337 		break;
1338 	case ISER_HELLO:
1339 		isert_err("iSER Hello message\n");
1340 		break;
1341 	default:
1342 		isert_warn("Unknown iSER hdr flags: 0x%02x\n", iser_ctrl->flags);
1343 		break;
1344 	}
1345 
1346 	isert_rx_opcode(isert_conn, rx_desc,
1347 			read_stag, read_va, write_stag, write_va);
1348 
1349 	ib_dma_sync_single_for_device(ib_dev, rx_desc->dma_addr,
1350 			ISER_RX_SIZE, DMA_FROM_DEVICE);
1351 }
1352 
1353 static void
1354 isert_login_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1355 {
1356 	struct isert_conn *isert_conn = wc->qp->qp_context;
1357 	struct ib_device *ib_dev = isert_conn->device->ib_device;
1358 
1359 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1360 		isert_print_wc(wc, "login recv");
1361 		return;
1362 	}
1363 
1364 	ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_desc->dma_addr,
1365 			ISER_RX_SIZE, DMA_FROM_DEVICE);
1366 
1367 	isert_conn->login_req_len = wc->byte_len - ISER_HEADERS_LEN;
1368 
1369 	if (isert_conn->conn) {
1370 		struct iscsi_login *login = isert_conn->conn->conn_login;
1371 
1372 		if (login && !login->first_request)
1373 			isert_rx_login_req(isert_conn);
1374 	}
1375 
1376 	mutex_lock(&isert_conn->mutex);
1377 	complete(&isert_conn->login_req_comp);
1378 	mutex_unlock(&isert_conn->mutex);
1379 
1380 	ib_dma_sync_single_for_device(ib_dev, isert_conn->login_desc->dma_addr,
1381 				ISER_RX_SIZE, DMA_FROM_DEVICE);
1382 }
1383 
1384 static void
1385 isert_rdma_rw_ctx_destroy(struct isert_cmd *cmd, struct isert_conn *conn)
1386 {
1387 	struct se_cmd *se_cmd = &cmd->iscsi_cmd->se_cmd;
1388 	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
1389 
1390 	if (!cmd->rw.nr_ops)
1391 		return;
1392 
1393 	if (isert_prot_cmd(conn, se_cmd)) {
1394 		rdma_rw_ctx_destroy_signature(&cmd->rw, conn->qp,
1395 				conn->cm_id->port_num, se_cmd->t_data_sg,
1396 				se_cmd->t_data_nents, se_cmd->t_prot_sg,
1397 				se_cmd->t_prot_nents, dir);
1398 	} else {
1399 		rdma_rw_ctx_destroy(&cmd->rw, conn->qp, conn->cm_id->port_num,
1400 				se_cmd->t_data_sg, se_cmd->t_data_nents, dir);
1401 	}
1402 
1403 	cmd->rw.nr_ops = 0;
1404 }
1405 
1406 static void
1407 isert_put_cmd(struct isert_cmd *isert_cmd, bool comp_err)
1408 {
1409 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1410 	struct isert_conn *isert_conn = isert_cmd->conn;
1411 	struct iscsi_conn *conn = isert_conn->conn;
1412 	struct iscsi_text_rsp *hdr;
1413 
1414 	isert_dbg("Cmd %p\n", isert_cmd);
1415 
1416 	switch (cmd->iscsi_opcode) {
1417 	case ISCSI_OP_SCSI_CMD:
1418 		spin_lock_bh(&conn->cmd_lock);
1419 		if (!list_empty(&cmd->i_conn_node))
1420 			list_del_init(&cmd->i_conn_node);
1421 		spin_unlock_bh(&conn->cmd_lock);
1422 
1423 		if (cmd->data_direction == DMA_TO_DEVICE) {
1424 			iscsit_stop_dataout_timer(cmd);
1425 			/*
1426 			 * Check for special case during comp_err where
1427 			 * WRITE_PENDING has been handed off from core,
1428 			 * but requires an extra target_put_sess_cmd()
1429 			 * before transport_generic_free_cmd() below.
1430 			 */
1431 			if (comp_err &&
1432 			    cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
1433 				struct se_cmd *se_cmd = &cmd->se_cmd;
1434 
1435 				target_put_sess_cmd(se_cmd);
1436 			}
1437 		}
1438 
1439 		isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1440 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1441 		break;
1442 	case ISCSI_OP_SCSI_TMFUNC:
1443 		spin_lock_bh(&conn->cmd_lock);
1444 		if (!list_empty(&cmd->i_conn_node))
1445 			list_del_init(&cmd->i_conn_node);
1446 		spin_unlock_bh(&conn->cmd_lock);
1447 
1448 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1449 		break;
1450 	case ISCSI_OP_REJECT:
1451 	case ISCSI_OP_NOOP_OUT:
1452 	case ISCSI_OP_TEXT:
1453 		hdr = (struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1454 		/* If the continue bit is on, keep the command alive */
1455 		if (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)
1456 			break;
1457 
1458 		spin_lock_bh(&conn->cmd_lock);
1459 		if (!list_empty(&cmd->i_conn_node))
1460 			list_del_init(&cmd->i_conn_node);
1461 		spin_unlock_bh(&conn->cmd_lock);
1462 
1463 		/*
1464 		 * Handle special case for REJECT when iscsi_add_reject*() has
1465 		 * overwritten the original iscsi_opcode assignment, and the
1466 		 * associated cmd->se_cmd needs to be released.
1467 		 */
1468 		if (cmd->se_cmd.se_tfo != NULL) {
1469 			isert_dbg("Calling transport_generic_free_cmd for 0x%02x\n",
1470 				 cmd->iscsi_opcode);
1471 			transport_generic_free_cmd(&cmd->se_cmd, 0);
1472 			break;
1473 		}
1474 		fallthrough;
1475 	default:
1476 		iscsit_release_cmd(cmd);
1477 		break;
1478 	}
1479 }
1480 
1481 static void
1482 isert_unmap_tx_desc(struct iser_tx_desc *tx_desc, struct ib_device *ib_dev)
1483 {
1484 	if (tx_desc->dma_addr != 0) {
1485 		isert_dbg("unmap single for tx_desc->dma_addr\n");
1486 		ib_dma_unmap_single(ib_dev, tx_desc->dma_addr,
1487 				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
1488 		tx_desc->dma_addr = 0;
1489 	}
1490 }
1491 
1492 static void
1493 isert_completion_put(struct iser_tx_desc *tx_desc, struct isert_cmd *isert_cmd,
1494 		     struct ib_device *ib_dev, bool comp_err)
1495 {
1496 	if (isert_cmd->pdu_buf_dma != 0) {
1497 		isert_dbg("unmap single for isert_cmd->pdu_buf_dma\n");
1498 		ib_dma_unmap_single(ib_dev, isert_cmd->pdu_buf_dma,
1499 				    isert_cmd->pdu_buf_len, DMA_TO_DEVICE);
1500 		isert_cmd->pdu_buf_dma = 0;
1501 	}
1502 
1503 	isert_unmap_tx_desc(tx_desc, ib_dev);
1504 	isert_put_cmd(isert_cmd, comp_err);
1505 }
1506 
1507 static int
1508 isert_check_pi_status(struct se_cmd *se_cmd, struct ib_mr *sig_mr)
1509 {
1510 	struct ib_mr_status mr_status;
1511 	int ret;
1512 
1513 	ret = ib_check_mr_status(sig_mr, IB_MR_CHECK_SIG_STATUS, &mr_status);
1514 	if (ret) {
1515 		isert_err("ib_check_mr_status failed, ret %d\n", ret);
1516 		goto fail_mr_status;
1517 	}
1518 
1519 	if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
1520 		u64 sec_offset_err;
1521 		u32 block_size = se_cmd->se_dev->dev_attrib.block_size + 8;
1522 
1523 		switch (mr_status.sig_err.err_type) {
1524 		case IB_SIG_BAD_GUARD:
1525 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1526 			break;
1527 		case IB_SIG_BAD_REFTAG:
1528 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1529 			break;
1530 		case IB_SIG_BAD_APPTAG:
1531 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED;
1532 			break;
1533 		}
1534 		sec_offset_err = mr_status.sig_err.sig_err_offset;
1535 		do_div(sec_offset_err, block_size);
1536 		se_cmd->bad_sector = sec_offset_err + se_cmd->t_task_lba;
1537 
1538 		isert_err("PI error found type %d at sector 0x%llx "
1539 			  "expected 0x%x vs actual 0x%x\n",
1540 			  mr_status.sig_err.err_type,
1541 			  (unsigned long long)se_cmd->bad_sector,
1542 			  mr_status.sig_err.expected,
1543 			  mr_status.sig_err.actual);
1544 		ret = 1;
1545 	}
1546 
1547 fail_mr_status:
1548 	return ret;
1549 }
1550 
1551 static void
1552 isert_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
1553 {
1554 	struct isert_conn *isert_conn = wc->qp->qp_context;
1555 	struct isert_device *device = isert_conn->device;
1556 	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
1557 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
1558 	struct se_cmd *cmd = &isert_cmd->iscsi_cmd->se_cmd;
1559 	int ret = 0;
1560 
1561 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1562 		isert_print_wc(wc, "rdma write");
1563 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1564 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1565 		isert_completion_put(desc, isert_cmd, device->ib_device, true);
1566 		return;
1567 	}
1568 
1569 	isert_dbg("Cmd %p\n", isert_cmd);
1570 
1571 	ret = isert_check_pi_status(cmd, isert_cmd->rw.reg->mr);
1572 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1573 
1574 	if (ret) {
1575 		/*
1576 		 * transport_generic_request_failure() expects to have
1577 		 * plus two references to handle queue-full, so re-add
1578 		 * one here as target-core will have already dropped
1579 		 * it after the first isert_put_datain() callback.
1580 		 */
1581 		kref_get(&cmd->cmd_kref);
1582 		transport_generic_request_failure(cmd, cmd->pi_err);
1583 	} else {
1584 		/*
1585 		 * XXX: isert_put_response() failure is not retried.
1586 		 */
1587 		ret = isert_put_response(isert_conn->conn, isert_cmd->iscsi_cmd);
1588 		if (ret)
1589 			pr_warn_ratelimited("isert_put_response() ret: %d\n", ret);
1590 	}
1591 }
1592 
1593 static void
1594 isert_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc)
1595 {
1596 	struct isert_conn *isert_conn = wc->qp->qp_context;
1597 	struct isert_device *device = isert_conn->device;
1598 	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
1599 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
1600 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1601 	struct se_cmd *se_cmd = &cmd->se_cmd;
1602 	int ret = 0;
1603 
1604 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1605 		isert_print_wc(wc, "rdma read");
1606 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1607 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1608 		isert_completion_put(desc, isert_cmd, device->ib_device, true);
1609 		return;
1610 	}
1611 
1612 	isert_dbg("Cmd %p\n", isert_cmd);
1613 
1614 	iscsit_stop_dataout_timer(cmd);
1615 
1616 	if (isert_prot_cmd(isert_conn, se_cmd))
1617 		ret = isert_check_pi_status(se_cmd, isert_cmd->rw.reg->mr);
1618 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1619 	cmd->write_data_done = 0;
1620 
1621 	isert_dbg("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
1622 	spin_lock_bh(&cmd->istate_lock);
1623 	cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1624 	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1625 	spin_unlock_bh(&cmd->istate_lock);
1626 
1627 	/*
1628 	 * transport_generic_request_failure() will drop the extra
1629 	 * se_cmd->cmd_kref reference after T10-PI error, and handle
1630 	 * any non-zero ->queue_status() callback error retries.
1631 	 */
1632 	if (ret)
1633 		transport_generic_request_failure(se_cmd, se_cmd->pi_err);
1634 	else
1635 		target_execute_cmd(se_cmd);
1636 }
1637 
1638 static void
1639 isert_do_control_comp(struct work_struct *work)
1640 {
1641 	struct isert_cmd *isert_cmd = container_of(work,
1642 			struct isert_cmd, comp_work);
1643 	struct isert_conn *isert_conn = isert_cmd->conn;
1644 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1645 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1646 
1647 	isert_dbg("Cmd %p i_state %d\n", isert_cmd, cmd->i_state);
1648 
1649 	switch (cmd->i_state) {
1650 	case ISTATE_SEND_TASKMGTRSP:
1651 		iscsit_tmr_post_handler(cmd, cmd->conn);
1652 		fallthrough;
1653 	case ISTATE_SEND_REJECT:
1654 	case ISTATE_SEND_TEXTRSP:
1655 		cmd->i_state = ISTATE_SENT_STATUS;
1656 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd,
1657 				     ib_dev, false);
1658 		break;
1659 	case ISTATE_SEND_LOGOUTRSP:
1660 		iscsit_logout_post_handler(cmd, cmd->conn);
1661 		break;
1662 	default:
1663 		isert_err("Unknown i_state %d\n", cmd->i_state);
1664 		dump_stack();
1665 		break;
1666 	}
1667 }
1668 
1669 static void
1670 isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc)
1671 {
1672 	struct isert_conn *isert_conn = wc->qp->qp_context;
1673 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1674 	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
1675 
1676 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1677 		isert_print_wc(wc, "login send");
1678 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1679 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1680 	}
1681 
1682 	isert_unmap_tx_desc(tx_desc, ib_dev);
1683 }
1684 
1685 static void
1686 isert_send_done(struct ib_cq *cq, struct ib_wc *wc)
1687 {
1688 	struct isert_conn *isert_conn = wc->qp->qp_context;
1689 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1690 	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
1691 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(tx_desc);
1692 
1693 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1694 		isert_print_wc(wc, "send");
1695 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1696 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1697 		isert_completion_put(tx_desc, isert_cmd, ib_dev, true);
1698 		return;
1699 	}
1700 
1701 	isert_dbg("Cmd %p\n", isert_cmd);
1702 
1703 	switch (isert_cmd->iscsi_cmd->i_state) {
1704 	case ISTATE_SEND_TASKMGTRSP:
1705 	case ISTATE_SEND_LOGOUTRSP:
1706 	case ISTATE_SEND_REJECT:
1707 	case ISTATE_SEND_TEXTRSP:
1708 		isert_unmap_tx_desc(tx_desc, ib_dev);
1709 
1710 		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
1711 		queue_work(isert_comp_wq, &isert_cmd->comp_work);
1712 		return;
1713 	default:
1714 		isert_cmd->iscsi_cmd->i_state = ISTATE_SENT_STATUS;
1715 		isert_completion_put(tx_desc, isert_cmd, ib_dev, false);
1716 		break;
1717 	}
1718 }
1719 
1720 static int
1721 isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
1722 {
1723 	int ret;
1724 
1725 	ret = isert_post_recv(isert_conn, isert_cmd->rx_desc);
1726 	if (ret) {
1727 		isert_err("ib_post_recv failed with %d\n", ret);
1728 		return ret;
1729 	}
1730 
1731 	ret = ib_post_send(isert_conn->qp, &isert_cmd->tx_desc.send_wr, NULL);
1732 	if (ret) {
1733 		isert_err("ib_post_send failed with %d\n", ret);
1734 		return ret;
1735 	}
1736 	return ret;
1737 }
1738 
1739 static int
1740 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
1741 {
1742 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1743 	struct isert_conn *isert_conn = conn->context;
1744 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1745 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
1746 				&isert_cmd->tx_desc.iscsi_header;
1747 
1748 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1749 	iscsit_build_rsp_pdu(cmd, conn, true, hdr);
1750 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1751 	/*
1752 	 * Attach SENSE DATA payload to iSCSI Response PDU
1753 	 */
1754 	if (cmd->se_cmd.sense_buffer &&
1755 	    ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1756 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
1757 		struct isert_device *device = isert_conn->device;
1758 		struct ib_device *ib_dev = device->ib_device;
1759 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1760 		u32 padding, pdu_len;
1761 
1762 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length,
1763 				   cmd->sense_buffer);
1764 		cmd->se_cmd.scsi_sense_length += sizeof(__be16);
1765 
1766 		padding = -(cmd->se_cmd.scsi_sense_length) & 3;
1767 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
1768 		pdu_len = cmd->se_cmd.scsi_sense_length + padding;
1769 
1770 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1771 				(void *)cmd->sense_buffer, pdu_len,
1772 				DMA_TO_DEVICE);
1773 		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1774 			return -ENOMEM;
1775 
1776 		isert_cmd->pdu_buf_len = pdu_len;
1777 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1778 		tx_dsg->length	= pdu_len;
1779 		tx_dsg->lkey	= device->pd->local_dma_lkey;
1780 		isert_cmd->tx_desc.num_sge = 2;
1781 	}
1782 
1783 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1784 
1785 	isert_dbg("Posting SCSI Response\n");
1786 
1787 	return isert_post_response(isert_conn, isert_cmd);
1788 }
1789 
1790 static void
1791 isert_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
1792 {
1793 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1794 	struct isert_conn *isert_conn = conn->context;
1795 
1796 	spin_lock_bh(&conn->cmd_lock);
1797 	if (!list_empty(&cmd->i_conn_node))
1798 		list_del_init(&cmd->i_conn_node);
1799 	spin_unlock_bh(&conn->cmd_lock);
1800 
1801 	if (cmd->data_direction == DMA_TO_DEVICE)
1802 		iscsit_stop_dataout_timer(cmd);
1803 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1804 }
1805 
1806 static enum target_prot_op
1807 isert_get_sup_prot_ops(struct iscsi_conn *conn)
1808 {
1809 	struct isert_conn *isert_conn = conn->context;
1810 	struct isert_device *device = isert_conn->device;
1811 
1812 	if (conn->tpg->tpg_attrib.t10_pi) {
1813 		if (device->pi_capable) {
1814 			isert_info("conn %p PI offload enabled\n", isert_conn);
1815 			isert_conn->pi_support = true;
1816 			return TARGET_PROT_ALL;
1817 		}
1818 	}
1819 
1820 	isert_info("conn %p PI offload disabled\n", isert_conn);
1821 	isert_conn->pi_support = false;
1822 
1823 	return TARGET_PROT_NORMAL;
1824 }
1825 
1826 static int
1827 isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
1828 		bool nopout_response)
1829 {
1830 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1831 	struct isert_conn *isert_conn = conn->context;
1832 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1833 
1834 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1835 	iscsit_build_nopin_rsp(cmd, conn, (struct iscsi_nopin *)
1836 			       &isert_cmd->tx_desc.iscsi_header,
1837 			       nopout_response);
1838 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1839 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1840 
1841 	isert_dbg("conn %p Posting NOPIN Response\n", isert_conn);
1842 
1843 	return isert_post_response(isert_conn, isert_cmd);
1844 }
1845 
1846 static int
1847 isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1848 {
1849 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1850 	struct isert_conn *isert_conn = conn->context;
1851 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1852 
1853 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1854 	iscsit_build_logout_rsp(cmd, conn, (struct iscsi_logout_rsp *)
1855 				&isert_cmd->tx_desc.iscsi_header);
1856 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1857 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1858 
1859 	isert_dbg("conn %p Posting Logout Response\n", isert_conn);
1860 
1861 	return isert_post_response(isert_conn, isert_cmd);
1862 }
1863 
1864 static int
1865 isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1866 {
1867 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1868 	struct isert_conn *isert_conn = conn->context;
1869 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1870 
1871 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1872 	iscsit_build_task_mgt_rsp(cmd, conn, (struct iscsi_tm_rsp *)
1873 				  &isert_cmd->tx_desc.iscsi_header);
1874 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1875 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1876 
1877 	isert_dbg("conn %p Posting Task Management Response\n", isert_conn);
1878 
1879 	return isert_post_response(isert_conn, isert_cmd);
1880 }
1881 
1882 static int
1883 isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1884 {
1885 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1886 	struct isert_conn *isert_conn = conn->context;
1887 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1888 	struct isert_device *device = isert_conn->device;
1889 	struct ib_device *ib_dev = device->ib_device;
1890 	struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1891 	struct iscsi_reject *hdr =
1892 		(struct iscsi_reject *)&isert_cmd->tx_desc.iscsi_header;
1893 
1894 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1895 	iscsit_build_reject(cmd, conn, hdr);
1896 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1897 
1898 	hton24(hdr->dlength, ISCSI_HDR_LEN);
1899 	isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1900 			(void *)cmd->buf_ptr, ISCSI_HDR_LEN,
1901 			DMA_TO_DEVICE);
1902 	if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1903 		return -ENOMEM;
1904 	isert_cmd->pdu_buf_len = ISCSI_HDR_LEN;
1905 	tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1906 	tx_dsg->length	= ISCSI_HDR_LEN;
1907 	tx_dsg->lkey	= device->pd->local_dma_lkey;
1908 	isert_cmd->tx_desc.num_sge = 2;
1909 
1910 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1911 
1912 	isert_dbg("conn %p Posting Reject\n", isert_conn);
1913 
1914 	return isert_post_response(isert_conn, isert_cmd);
1915 }
1916 
1917 static int
1918 isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1919 {
1920 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1921 	struct isert_conn *isert_conn = conn->context;
1922 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1923 	struct iscsi_text_rsp *hdr =
1924 		(struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1925 	u32 txt_rsp_len;
1926 	int rc;
1927 
1928 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1929 	rc = iscsit_build_text_rsp(cmd, conn, hdr, ISCSI_INFINIBAND);
1930 	if (rc < 0)
1931 		return rc;
1932 
1933 	txt_rsp_len = rc;
1934 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1935 
1936 	if (txt_rsp_len) {
1937 		struct isert_device *device = isert_conn->device;
1938 		struct ib_device *ib_dev = device->ib_device;
1939 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1940 		void *txt_rsp_buf = cmd->buf_ptr;
1941 
1942 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1943 				txt_rsp_buf, txt_rsp_len, DMA_TO_DEVICE);
1944 		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1945 			return -ENOMEM;
1946 
1947 		isert_cmd->pdu_buf_len = txt_rsp_len;
1948 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1949 		tx_dsg->length	= txt_rsp_len;
1950 		tx_dsg->lkey	= device->pd->local_dma_lkey;
1951 		isert_cmd->tx_desc.num_sge = 2;
1952 	}
1953 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1954 
1955 	isert_dbg("conn %p Text Response\n", isert_conn);
1956 
1957 	return isert_post_response(isert_conn, isert_cmd);
1958 }
1959 
1960 static inline void
1961 isert_set_dif_domain(struct se_cmd *se_cmd, struct ib_sig_domain *domain)
1962 {
1963 	domain->sig_type = IB_SIG_TYPE_T10_DIF;
1964 	domain->sig.dif.bg_type = IB_T10DIF_CRC;
1965 	domain->sig.dif.pi_interval = se_cmd->se_dev->dev_attrib.block_size;
1966 	domain->sig.dif.ref_tag = se_cmd->reftag_seed;
1967 	/*
1968 	 * At the moment we hard code those, but if in the future
1969 	 * the target core would like to use it, we will take it
1970 	 * from se_cmd.
1971 	 */
1972 	domain->sig.dif.apptag_check_mask = 0xffff;
1973 	domain->sig.dif.app_escape = true;
1974 	domain->sig.dif.ref_escape = true;
1975 	if (se_cmd->prot_type == TARGET_DIF_TYPE1_PROT ||
1976 	    se_cmd->prot_type == TARGET_DIF_TYPE2_PROT)
1977 		domain->sig.dif.ref_remap = true;
1978 };
1979 
1980 static int
1981 isert_set_sig_attrs(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs)
1982 {
1983 	memset(sig_attrs, 0, sizeof(*sig_attrs));
1984 
1985 	switch (se_cmd->prot_op) {
1986 	case TARGET_PROT_DIN_INSERT:
1987 	case TARGET_PROT_DOUT_STRIP:
1988 		sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
1989 		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
1990 		break;
1991 	case TARGET_PROT_DOUT_INSERT:
1992 	case TARGET_PROT_DIN_STRIP:
1993 		sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
1994 		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
1995 		break;
1996 	case TARGET_PROT_DIN_PASS:
1997 	case TARGET_PROT_DOUT_PASS:
1998 		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
1999 		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
2000 		break;
2001 	default:
2002 		isert_err("Unsupported PI operation %d\n", se_cmd->prot_op);
2003 		return -EINVAL;
2004 	}
2005 
2006 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_GUARD)
2007 		sig_attrs->check_mask |= IB_SIG_CHECK_GUARD;
2008 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_APPTAG)
2009 		sig_attrs->check_mask |= IB_SIG_CHECK_APPTAG;
2010 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)
2011 		sig_attrs->check_mask |= IB_SIG_CHECK_REFTAG;
2012 
2013 	return 0;
2014 }
2015 
2016 static int
2017 isert_rdma_rw_ctx_post(struct isert_cmd *cmd, struct isert_conn *conn,
2018 		struct ib_cqe *cqe, struct ib_send_wr *chain_wr)
2019 {
2020 	struct se_cmd *se_cmd = &cmd->iscsi_cmd->se_cmd;
2021 	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
2022 	u8 port_num = conn->cm_id->port_num;
2023 	u64 addr;
2024 	u32 rkey, offset;
2025 	int ret;
2026 
2027 	if (cmd->ctx_init_done)
2028 		goto rdma_ctx_post;
2029 
2030 	if (dir == DMA_FROM_DEVICE) {
2031 		addr = cmd->write_va;
2032 		rkey = cmd->write_stag;
2033 		offset = cmd->iscsi_cmd->write_data_done;
2034 	} else {
2035 		addr = cmd->read_va;
2036 		rkey = cmd->read_stag;
2037 		offset = 0;
2038 	}
2039 
2040 	if (isert_prot_cmd(conn, se_cmd)) {
2041 		struct ib_sig_attrs sig_attrs;
2042 
2043 		ret = isert_set_sig_attrs(se_cmd, &sig_attrs);
2044 		if (ret)
2045 			return ret;
2046 
2047 		WARN_ON_ONCE(offset);
2048 		ret = rdma_rw_ctx_signature_init(&cmd->rw, conn->qp, port_num,
2049 				se_cmd->t_data_sg, se_cmd->t_data_nents,
2050 				se_cmd->t_prot_sg, se_cmd->t_prot_nents,
2051 				&sig_attrs, addr, rkey, dir);
2052 	} else {
2053 		ret = rdma_rw_ctx_init(&cmd->rw, conn->qp, port_num,
2054 				se_cmd->t_data_sg, se_cmd->t_data_nents,
2055 				offset, addr, rkey, dir);
2056 	}
2057 
2058 	if (ret < 0) {
2059 		isert_err("Cmd: %p failed to prepare RDMA res\n", cmd);
2060 		return ret;
2061 	}
2062 
2063 	cmd->ctx_init_done = true;
2064 
2065 rdma_ctx_post:
2066 	ret = rdma_rw_ctx_post(&cmd->rw, conn->qp, port_num, cqe, chain_wr);
2067 	if (ret < 0)
2068 		isert_err("Cmd: %p failed to post RDMA res\n", cmd);
2069 	return ret;
2070 }
2071 
2072 static int
2073 isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
2074 {
2075 	struct se_cmd *se_cmd = &cmd->se_cmd;
2076 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2077 	struct isert_conn *isert_conn = conn->context;
2078 	struct ib_cqe *cqe = NULL;
2079 	struct ib_send_wr *chain_wr = NULL;
2080 	int rc;
2081 
2082 	isert_dbg("Cmd: %p RDMA_WRITE data_length: %u\n",
2083 		 isert_cmd, se_cmd->data_length);
2084 
2085 	if (isert_prot_cmd(isert_conn, se_cmd)) {
2086 		isert_cmd->tx_desc.tx_cqe.done = isert_rdma_write_done;
2087 		cqe = &isert_cmd->tx_desc.tx_cqe;
2088 	} else {
2089 		/*
2090 		 * Build isert_conn->tx_desc for iSCSI response PDU and attach
2091 		 */
2092 		isert_create_send_desc(isert_conn, isert_cmd,
2093 				       &isert_cmd->tx_desc);
2094 		iscsit_build_rsp_pdu(cmd, conn, true, (struct iscsi_scsi_rsp *)
2095 				     &isert_cmd->tx_desc.iscsi_header);
2096 		isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2097 		isert_init_send_wr(isert_conn, isert_cmd,
2098 				   &isert_cmd->tx_desc.send_wr);
2099 
2100 		rc = isert_post_recv(isert_conn, isert_cmd->rx_desc);
2101 		if (rc) {
2102 			isert_err("ib_post_recv failed with %d\n", rc);
2103 			return rc;
2104 		}
2105 
2106 		chain_wr = &isert_cmd->tx_desc.send_wr;
2107 	}
2108 
2109 	rc = isert_rdma_rw_ctx_post(isert_cmd, isert_conn, cqe, chain_wr);
2110 	isert_dbg("Cmd: %p posted RDMA_WRITE for iSER Data READ rc: %d\n",
2111 		  isert_cmd, rc);
2112 	return rc;
2113 }
2114 
2115 static int
2116 isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
2117 {
2118 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2119 	int ret;
2120 
2121 	isert_dbg("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
2122 		 isert_cmd, cmd->se_cmd.data_length, cmd->write_data_done);
2123 
2124 	isert_cmd->tx_desc.tx_cqe.done = isert_rdma_read_done;
2125 	ret = isert_rdma_rw_ctx_post(isert_cmd, conn->context,
2126 				     &isert_cmd->tx_desc.tx_cqe, NULL);
2127 
2128 	isert_dbg("Cmd: %p posted RDMA_READ memory for ISER Data WRITE rc: %d\n",
2129 		 isert_cmd, ret);
2130 	return ret;
2131 }
2132 
2133 static int
2134 isert_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2135 {
2136 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2137 	int ret = 0;
2138 
2139 	switch (state) {
2140 	case ISTATE_REMOVE:
2141 		spin_lock_bh(&conn->cmd_lock);
2142 		list_del_init(&cmd->i_conn_node);
2143 		spin_unlock_bh(&conn->cmd_lock);
2144 		isert_put_cmd(isert_cmd, true);
2145 		break;
2146 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
2147 		ret = isert_put_nopin(cmd, conn, false);
2148 		break;
2149 	default:
2150 		isert_err("Unknown immediate state: 0x%02x\n", state);
2151 		ret = -EINVAL;
2152 		break;
2153 	}
2154 
2155 	return ret;
2156 }
2157 
2158 static int
2159 isert_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2160 {
2161 	struct isert_conn *isert_conn = conn->context;
2162 	int ret;
2163 
2164 	switch (state) {
2165 	case ISTATE_SEND_LOGOUTRSP:
2166 		ret = isert_put_logout_rsp(cmd, conn);
2167 		if (!ret)
2168 			isert_conn->logout_posted = true;
2169 		break;
2170 	case ISTATE_SEND_NOPIN:
2171 		ret = isert_put_nopin(cmd, conn, true);
2172 		break;
2173 	case ISTATE_SEND_TASKMGTRSP:
2174 		ret = isert_put_tm_rsp(cmd, conn);
2175 		break;
2176 	case ISTATE_SEND_REJECT:
2177 		ret = isert_put_reject(cmd, conn);
2178 		break;
2179 	case ISTATE_SEND_TEXTRSP:
2180 		ret = isert_put_text_rsp(cmd, conn);
2181 		break;
2182 	case ISTATE_SEND_STATUS:
2183 		/*
2184 		 * Special case for sending non GOOD SCSI status from TX thread
2185 		 * context during pre se_cmd excecution failure.
2186 		 */
2187 		ret = isert_put_response(conn, cmd);
2188 		break;
2189 	default:
2190 		isert_err("Unknown response state: 0x%02x\n", state);
2191 		ret = -EINVAL;
2192 		break;
2193 	}
2194 
2195 	return ret;
2196 }
2197 
2198 struct rdma_cm_id *
2199 isert_setup_id(struct isert_np *isert_np)
2200 {
2201 	struct iscsi_np *np = isert_np->np;
2202 	struct rdma_cm_id *id;
2203 	struct sockaddr *sa;
2204 	int ret;
2205 
2206 	sa = (struct sockaddr *)&np->np_sockaddr;
2207 	isert_dbg("ksockaddr: %p, sa: %p\n", &np->np_sockaddr, sa);
2208 
2209 	id = rdma_create_id(&init_net, isert_cma_handler, isert_np,
2210 			    RDMA_PS_TCP, IB_QPT_RC);
2211 	if (IS_ERR(id)) {
2212 		isert_err("rdma_create_id() failed: %ld\n", PTR_ERR(id));
2213 		ret = PTR_ERR(id);
2214 		goto out;
2215 	}
2216 	isert_dbg("id %p context %p\n", id, id->context);
2217 
2218 	ret = rdma_bind_addr(id, sa);
2219 	if (ret) {
2220 		isert_err("rdma_bind_addr() failed: %d\n", ret);
2221 		goto out_id;
2222 	}
2223 
2224 	ret = rdma_listen(id, 0);
2225 	if (ret) {
2226 		isert_err("rdma_listen() failed: %d\n", ret);
2227 		goto out_id;
2228 	}
2229 
2230 	return id;
2231 out_id:
2232 	rdma_destroy_id(id);
2233 out:
2234 	return ERR_PTR(ret);
2235 }
2236 
2237 static int
2238 isert_setup_np(struct iscsi_np *np,
2239 	       struct sockaddr_storage *ksockaddr)
2240 {
2241 	struct isert_np *isert_np;
2242 	struct rdma_cm_id *isert_lid;
2243 	int ret;
2244 
2245 	isert_np = kzalloc(sizeof(struct isert_np), GFP_KERNEL);
2246 	if (!isert_np)
2247 		return -ENOMEM;
2248 
2249 	sema_init(&isert_np->sem, 0);
2250 	mutex_init(&isert_np->mutex);
2251 	INIT_LIST_HEAD(&isert_np->accepted);
2252 	INIT_LIST_HEAD(&isert_np->pending);
2253 	isert_np->np = np;
2254 
2255 	/*
2256 	 * Setup the np->np_sockaddr from the passed sockaddr setup
2257 	 * in iscsi_target_configfs.c code..
2258 	 */
2259 	memcpy(&np->np_sockaddr, ksockaddr,
2260 	       sizeof(struct sockaddr_storage));
2261 
2262 	isert_lid = isert_setup_id(isert_np);
2263 	if (IS_ERR(isert_lid)) {
2264 		ret = PTR_ERR(isert_lid);
2265 		goto out;
2266 	}
2267 
2268 	isert_np->cm_id = isert_lid;
2269 	np->np_context = isert_np;
2270 
2271 	return 0;
2272 
2273 out:
2274 	kfree(isert_np);
2275 
2276 	return ret;
2277 }
2278 
2279 static int
2280 isert_rdma_accept(struct isert_conn *isert_conn)
2281 {
2282 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
2283 	struct rdma_conn_param cp;
2284 	int ret;
2285 	struct iser_cm_hdr rsp_hdr;
2286 
2287 	memset(&cp, 0, sizeof(struct rdma_conn_param));
2288 	cp.initiator_depth = isert_conn->initiator_depth;
2289 	cp.retry_count = 7;
2290 	cp.rnr_retry_count = 7;
2291 
2292 	memset(&rsp_hdr, 0, sizeof(rsp_hdr));
2293 	rsp_hdr.flags = ISERT_ZBVA_NOT_USED;
2294 	if (!isert_conn->snd_w_inv)
2295 		rsp_hdr.flags = rsp_hdr.flags | ISERT_SEND_W_INV_NOT_USED;
2296 	cp.private_data = (void *)&rsp_hdr;
2297 	cp.private_data_len = sizeof(rsp_hdr);
2298 
2299 	ret = rdma_accept(cm_id, &cp);
2300 	if (ret) {
2301 		isert_err("rdma_accept() failed with: %d\n", ret);
2302 		return ret;
2303 	}
2304 
2305 	return 0;
2306 }
2307 
2308 static int
2309 isert_get_login_rx(struct iscsi_conn *conn, struct iscsi_login *login)
2310 {
2311 	struct isert_conn *isert_conn = conn->context;
2312 	int ret;
2313 
2314 	isert_info("before login_req comp conn: %p\n", isert_conn);
2315 	ret = wait_for_completion_interruptible(&isert_conn->login_req_comp);
2316 	if (ret) {
2317 		isert_err("isert_conn %p interrupted before got login req\n",
2318 			  isert_conn);
2319 		return ret;
2320 	}
2321 	reinit_completion(&isert_conn->login_req_comp);
2322 
2323 	/*
2324 	 * For login requests after the first PDU, isert_rx_login_req() will
2325 	 * kick schedule_delayed_work(&conn->login_work) as the packet is
2326 	 * received, which turns this callback from iscsi_target_do_login_rx()
2327 	 * into a NOP.
2328 	 */
2329 	if (!login->first_request)
2330 		return 0;
2331 
2332 	isert_rx_login_req(isert_conn);
2333 
2334 	isert_info("before login_comp conn: %p\n", conn);
2335 	ret = wait_for_completion_interruptible(&isert_conn->login_comp);
2336 	if (ret)
2337 		return ret;
2338 
2339 	isert_info("processing login->req: %p\n", login->req);
2340 
2341 	return 0;
2342 }
2343 
2344 static void
2345 isert_set_conn_info(struct iscsi_np *np, struct iscsi_conn *conn,
2346 		    struct isert_conn *isert_conn)
2347 {
2348 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
2349 	struct rdma_route *cm_route = &cm_id->route;
2350 
2351 	conn->login_family = np->np_sockaddr.ss_family;
2352 
2353 	conn->login_sockaddr = cm_route->addr.dst_addr;
2354 	conn->local_sockaddr = cm_route->addr.src_addr;
2355 }
2356 
2357 static int
2358 isert_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
2359 {
2360 	struct isert_np *isert_np = np->np_context;
2361 	struct isert_conn *isert_conn;
2362 	int ret;
2363 
2364 accept_wait:
2365 	ret = down_interruptible(&isert_np->sem);
2366 	if (ret)
2367 		return -ENODEV;
2368 
2369 	spin_lock_bh(&np->np_thread_lock);
2370 	if (np->np_thread_state >= ISCSI_NP_THREAD_RESET) {
2371 		spin_unlock_bh(&np->np_thread_lock);
2372 		isert_dbg("np_thread_state %d\n",
2373 			 np->np_thread_state);
2374 		/**
2375 		 * No point in stalling here when np_thread
2376 		 * is in state RESET/SHUTDOWN/EXIT - bail
2377 		 **/
2378 		return -ENODEV;
2379 	}
2380 	spin_unlock_bh(&np->np_thread_lock);
2381 
2382 	mutex_lock(&isert_np->mutex);
2383 	if (list_empty(&isert_np->pending)) {
2384 		mutex_unlock(&isert_np->mutex);
2385 		goto accept_wait;
2386 	}
2387 	isert_conn = list_first_entry(&isert_np->pending,
2388 			struct isert_conn, node);
2389 	list_del_init(&isert_conn->node);
2390 	mutex_unlock(&isert_np->mutex);
2391 
2392 	conn->context = isert_conn;
2393 	isert_conn->conn = conn;
2394 	isert_conn->state = ISER_CONN_BOUND;
2395 
2396 	isert_set_conn_info(np, conn, isert_conn);
2397 
2398 	isert_dbg("Processing isert_conn: %p\n", isert_conn);
2399 
2400 	return 0;
2401 }
2402 
2403 static void
2404 isert_free_np(struct iscsi_np *np)
2405 {
2406 	struct isert_np *isert_np = np->np_context;
2407 	struct isert_conn *isert_conn, *n;
2408 
2409 	if (isert_np->cm_id)
2410 		rdma_destroy_id(isert_np->cm_id);
2411 
2412 	/*
2413 	 * FIXME: At this point we don't have a good way to insure
2414 	 * that at this point we don't have hanging connections that
2415 	 * completed RDMA establishment but didn't start iscsi login
2416 	 * process. So work-around this by cleaning up what ever piled
2417 	 * up in accepted and pending lists.
2418 	 */
2419 	mutex_lock(&isert_np->mutex);
2420 	if (!list_empty(&isert_np->pending)) {
2421 		isert_info("Still have isert pending connections\n");
2422 		list_for_each_entry_safe(isert_conn, n,
2423 					 &isert_np->pending,
2424 					 node) {
2425 			isert_info("cleaning isert_conn %p state (%d)\n",
2426 				   isert_conn, isert_conn->state);
2427 			isert_connect_release(isert_conn);
2428 		}
2429 	}
2430 
2431 	if (!list_empty(&isert_np->accepted)) {
2432 		isert_info("Still have isert accepted connections\n");
2433 		list_for_each_entry_safe(isert_conn, n,
2434 					 &isert_np->accepted,
2435 					 node) {
2436 			isert_info("cleaning isert_conn %p state (%d)\n",
2437 				   isert_conn, isert_conn->state);
2438 			isert_connect_release(isert_conn);
2439 		}
2440 	}
2441 	mutex_unlock(&isert_np->mutex);
2442 
2443 	np->np_context = NULL;
2444 	kfree(isert_np);
2445 }
2446 
2447 static void isert_release_work(struct work_struct *work)
2448 {
2449 	struct isert_conn *isert_conn = container_of(work,
2450 						     struct isert_conn,
2451 						     release_work);
2452 
2453 	isert_info("Starting release conn %p\n", isert_conn);
2454 
2455 	mutex_lock(&isert_conn->mutex);
2456 	isert_conn->state = ISER_CONN_DOWN;
2457 	mutex_unlock(&isert_conn->mutex);
2458 
2459 	isert_info("Destroying conn %p\n", isert_conn);
2460 	isert_put_conn(isert_conn);
2461 }
2462 
2463 static void
2464 isert_wait4logout(struct isert_conn *isert_conn)
2465 {
2466 	struct iscsi_conn *conn = isert_conn->conn;
2467 
2468 	isert_info("conn %p\n", isert_conn);
2469 
2470 	if (isert_conn->logout_posted) {
2471 		isert_info("conn %p wait for conn_logout_comp\n", isert_conn);
2472 		wait_for_completion_timeout(&conn->conn_logout_comp,
2473 					    SECONDS_FOR_LOGOUT_COMP * HZ);
2474 	}
2475 }
2476 
2477 static void
2478 isert_wait4cmds(struct iscsi_conn *conn)
2479 {
2480 	isert_info("iscsi_conn %p\n", conn);
2481 
2482 	if (conn->sess) {
2483 		target_sess_cmd_list_set_waiting(conn->sess->se_sess);
2484 		target_wait_for_sess_cmds(conn->sess->se_sess);
2485 	}
2486 }
2487 
2488 /**
2489  * isert_put_unsol_pending_cmds() - Drop commands waiting for
2490  *     unsolicitate dataout
2491  * @conn:    iscsi connection
2492  *
2493  * We might still have commands that are waiting for unsolicited
2494  * dataouts messages. We must put the extra reference on those
2495  * before blocking on the target_wait_for_session_cmds
2496  */
2497 static void
2498 isert_put_unsol_pending_cmds(struct iscsi_conn *conn)
2499 {
2500 	struct iscsi_cmd *cmd, *tmp;
2501 	static LIST_HEAD(drop_cmd_list);
2502 
2503 	spin_lock_bh(&conn->cmd_lock);
2504 	list_for_each_entry_safe(cmd, tmp, &conn->conn_cmd_list, i_conn_node) {
2505 		if ((cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA) &&
2506 		    (cmd->write_data_done < conn->sess->sess_ops->FirstBurstLength) &&
2507 		    (cmd->write_data_done < cmd->se_cmd.data_length))
2508 			list_move_tail(&cmd->i_conn_node, &drop_cmd_list);
2509 	}
2510 	spin_unlock_bh(&conn->cmd_lock);
2511 
2512 	list_for_each_entry_safe(cmd, tmp, &drop_cmd_list, i_conn_node) {
2513 		list_del_init(&cmd->i_conn_node);
2514 		if (cmd->i_state != ISTATE_REMOVE) {
2515 			struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2516 
2517 			isert_info("conn %p dropping cmd %p\n", conn, cmd);
2518 			isert_put_cmd(isert_cmd, true);
2519 		}
2520 	}
2521 }
2522 
2523 static void isert_wait_conn(struct iscsi_conn *conn)
2524 {
2525 	struct isert_conn *isert_conn = conn->context;
2526 
2527 	isert_info("Starting conn %p\n", isert_conn);
2528 
2529 	mutex_lock(&isert_conn->mutex);
2530 	isert_conn_terminate(isert_conn);
2531 	mutex_unlock(&isert_conn->mutex);
2532 
2533 	ib_drain_qp(isert_conn->qp);
2534 	isert_put_unsol_pending_cmds(conn);
2535 	isert_wait4cmds(conn);
2536 	isert_wait4logout(isert_conn);
2537 
2538 	queue_work(isert_release_wq, &isert_conn->release_work);
2539 }
2540 
2541 static void isert_free_conn(struct iscsi_conn *conn)
2542 {
2543 	struct isert_conn *isert_conn = conn->context;
2544 
2545 	ib_drain_qp(isert_conn->qp);
2546 	isert_put_conn(isert_conn);
2547 }
2548 
2549 static void isert_get_rx_pdu(struct iscsi_conn *conn)
2550 {
2551 	struct completion comp;
2552 
2553 	init_completion(&comp);
2554 
2555 	wait_for_completion_interruptible(&comp);
2556 }
2557 
2558 static struct iscsit_transport iser_target_transport = {
2559 	.name			= "IB/iSER",
2560 	.transport_type		= ISCSI_INFINIBAND,
2561 	.rdma_shutdown		= true,
2562 	.priv_size		= sizeof(struct isert_cmd),
2563 	.owner			= THIS_MODULE,
2564 	.iscsit_setup_np	= isert_setup_np,
2565 	.iscsit_accept_np	= isert_accept_np,
2566 	.iscsit_free_np		= isert_free_np,
2567 	.iscsit_wait_conn	= isert_wait_conn,
2568 	.iscsit_free_conn	= isert_free_conn,
2569 	.iscsit_get_login_rx	= isert_get_login_rx,
2570 	.iscsit_put_login_tx	= isert_put_login_tx,
2571 	.iscsit_immediate_queue	= isert_immediate_queue,
2572 	.iscsit_response_queue	= isert_response_queue,
2573 	.iscsit_get_dataout	= isert_get_dataout,
2574 	.iscsit_queue_data_in	= isert_put_datain,
2575 	.iscsit_queue_status	= isert_put_response,
2576 	.iscsit_aborted_task	= isert_aborted_task,
2577 	.iscsit_get_rx_pdu	= isert_get_rx_pdu,
2578 	.iscsit_get_sup_prot_ops = isert_get_sup_prot_ops,
2579 };
2580 
2581 static int __init isert_init(void)
2582 {
2583 	int ret;
2584 
2585 	isert_comp_wq = alloc_workqueue("isert_comp_wq",
2586 					WQ_UNBOUND | WQ_HIGHPRI, 0);
2587 	if (!isert_comp_wq) {
2588 		isert_err("Unable to allocate isert_comp_wq\n");
2589 		return -ENOMEM;
2590 	}
2591 
2592 	isert_release_wq = alloc_workqueue("isert_release_wq", WQ_UNBOUND,
2593 					WQ_UNBOUND_MAX_ACTIVE);
2594 	if (!isert_release_wq) {
2595 		isert_err("Unable to allocate isert_release_wq\n");
2596 		ret = -ENOMEM;
2597 		goto destroy_comp_wq;
2598 	}
2599 
2600 	iscsit_register_transport(&iser_target_transport);
2601 	isert_info("iSER_TARGET[0] - Loaded iser_target_transport\n");
2602 
2603 	return 0;
2604 
2605 destroy_comp_wq:
2606 	destroy_workqueue(isert_comp_wq);
2607 
2608 	return ret;
2609 }
2610 
2611 static void __exit isert_exit(void)
2612 {
2613 	flush_scheduled_work();
2614 	destroy_workqueue(isert_release_wq);
2615 	destroy_workqueue(isert_comp_wq);
2616 	iscsit_unregister_transport(&iser_target_transport);
2617 	isert_info("iSER_TARGET[0] - Released iser_target_transport\n");
2618 }
2619 
2620 MODULE_DESCRIPTION("iSER-Target for mainline target infrastructure");
2621 MODULE_AUTHOR("nab@Linux-iSCSI.org");
2622 MODULE_LICENSE("GPL");
2623 
2624 module_init(isert_init);
2625 module_exit(isert_exit);
2626