1 /*******************************************************************************
2  * This file contains iSCSI extentions for RDMA (iSER) Verbs
3  *
4  * (c) Copyright 2013 Datera, Inc.
5  *
6  * Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ****************************************************************************/
18 
19 #include <linux/string.h>
20 #include <linux/module.h>
21 #include <linux/scatterlist.h>
22 #include <linux/socket.h>
23 #include <linux/in.h>
24 #include <linux/in6.h>
25 #include <linux/llist.h>
26 #include <rdma/ib_verbs.h>
27 #include <rdma/rdma_cm.h>
28 #include <target/target_core_base.h>
29 #include <target/target_core_fabric.h>
30 #include <target/iscsi/iscsi_transport.h>
31 
32 #include "isert_proto.h"
33 #include "ib_isert.h"
34 
35 #define	ISERT_MAX_CONN		8
36 #define ISER_MAX_RX_CQ_LEN	(ISERT_QP_MAX_RECV_DTOS * ISERT_MAX_CONN)
37 #define ISER_MAX_TX_CQ_LEN	(ISERT_QP_MAX_REQ_DTOS  * ISERT_MAX_CONN)
38 
39 static DEFINE_MUTEX(device_list_mutex);
40 static LIST_HEAD(device_list);
41 static struct workqueue_struct *isert_rx_wq;
42 static struct workqueue_struct *isert_comp_wq;
43 
44 static void
45 isert_unmap_cmd(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn);
46 static int
47 isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
48 	       struct isert_rdma_wr *wr);
49 static void
50 isert_unreg_rdma(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn);
51 static int
52 isert_reg_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
53 	       struct isert_rdma_wr *wr);
54 
55 static void
56 isert_qp_event_callback(struct ib_event *e, void *context)
57 {
58 	struct isert_conn *isert_conn = (struct isert_conn *)context;
59 
60 	pr_err("isert_qp_event_callback event: %d\n", e->event);
61 	switch (e->event) {
62 	case IB_EVENT_COMM_EST:
63 		rdma_notify(isert_conn->conn_cm_id, IB_EVENT_COMM_EST);
64 		break;
65 	case IB_EVENT_QP_LAST_WQE_REACHED:
66 		pr_warn("Reached TX IB_EVENT_QP_LAST_WQE_REACHED:\n");
67 		break;
68 	default:
69 		break;
70 	}
71 }
72 
73 static int
74 isert_query_device(struct ib_device *ib_dev, struct ib_device_attr *devattr)
75 {
76 	int ret;
77 
78 	ret = ib_query_device(ib_dev, devattr);
79 	if (ret) {
80 		pr_err("ib_query_device() failed: %d\n", ret);
81 		return ret;
82 	}
83 	pr_debug("devattr->max_sge: %d\n", devattr->max_sge);
84 	pr_debug("devattr->max_sge_rd: %d\n", devattr->max_sge_rd);
85 
86 	return 0;
87 }
88 
89 static int
90 isert_conn_setup_qp(struct isert_conn *isert_conn, struct rdma_cm_id *cma_id)
91 {
92 	struct isert_device *device = isert_conn->conn_device;
93 	struct ib_qp_init_attr attr;
94 	int ret, index, min_index = 0;
95 
96 	mutex_lock(&device_list_mutex);
97 	for (index = 0; index < device->cqs_used; index++)
98 		if (device->cq_active_qps[index] <
99 		    device->cq_active_qps[min_index])
100 			min_index = index;
101 	device->cq_active_qps[min_index]++;
102 	pr_debug("isert_conn_setup_qp: Using min_index: %d\n", min_index);
103 	mutex_unlock(&device_list_mutex);
104 
105 	memset(&attr, 0, sizeof(struct ib_qp_init_attr));
106 	attr.event_handler = isert_qp_event_callback;
107 	attr.qp_context = isert_conn;
108 	attr.send_cq = device->dev_tx_cq[min_index];
109 	attr.recv_cq = device->dev_rx_cq[min_index];
110 	attr.cap.max_send_wr = ISERT_QP_MAX_REQ_DTOS;
111 	attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS;
112 	/*
113 	 * FIXME: Use devattr.max_sge - 2 for max_send_sge as
114 	 * work-around for RDMA_READ..
115 	 */
116 	attr.cap.max_send_sge = device->dev_attr.max_sge - 2;
117 	isert_conn->max_sge = attr.cap.max_send_sge;
118 
119 	attr.cap.max_recv_sge = 1;
120 	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
121 	attr.qp_type = IB_QPT_RC;
122 
123 	pr_debug("isert_conn_setup_qp cma_id->device: %p\n",
124 		 cma_id->device);
125 	pr_debug("isert_conn_setup_qp conn_pd->device: %p\n",
126 		 isert_conn->conn_pd->device);
127 
128 	ret = rdma_create_qp(cma_id, isert_conn->conn_pd, &attr);
129 	if (ret) {
130 		pr_err("rdma_create_qp failed for cma_id %d\n", ret);
131 		return ret;
132 	}
133 	isert_conn->conn_qp = cma_id->qp;
134 	pr_debug("rdma_create_qp() returned success >>>>>>>>>>>>>>>>>>>>>>>>>.\n");
135 
136 	return 0;
137 }
138 
139 static void
140 isert_cq_event_callback(struct ib_event *e, void *context)
141 {
142 	pr_debug("isert_cq_event_callback event: %d\n", e->event);
143 }
144 
145 static int
146 isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
147 {
148 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
149 	struct iser_rx_desc *rx_desc;
150 	struct ib_sge *rx_sg;
151 	u64 dma_addr;
152 	int i, j;
153 
154 	isert_conn->conn_rx_descs = kzalloc(ISERT_QP_MAX_RECV_DTOS *
155 				sizeof(struct iser_rx_desc), GFP_KERNEL);
156 	if (!isert_conn->conn_rx_descs)
157 		goto fail;
158 
159 	rx_desc = isert_conn->conn_rx_descs;
160 
161 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
162 		dma_addr = ib_dma_map_single(ib_dev, (void *)rx_desc,
163 					ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
164 		if (ib_dma_mapping_error(ib_dev, dma_addr))
165 			goto dma_map_fail;
166 
167 		rx_desc->dma_addr = dma_addr;
168 
169 		rx_sg = &rx_desc->rx_sg;
170 		rx_sg->addr = rx_desc->dma_addr;
171 		rx_sg->length = ISER_RX_PAYLOAD_SIZE;
172 		rx_sg->lkey = isert_conn->conn_mr->lkey;
173 	}
174 
175 	isert_conn->conn_rx_desc_head = 0;
176 	return 0;
177 
178 dma_map_fail:
179 	rx_desc = isert_conn->conn_rx_descs;
180 	for (j = 0; j < i; j++, rx_desc++) {
181 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
182 				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
183 	}
184 	kfree(isert_conn->conn_rx_descs);
185 	isert_conn->conn_rx_descs = NULL;
186 fail:
187 	return -ENOMEM;
188 }
189 
190 static void
191 isert_free_rx_descriptors(struct isert_conn *isert_conn)
192 {
193 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
194 	struct iser_rx_desc *rx_desc;
195 	int i;
196 
197 	if (!isert_conn->conn_rx_descs)
198 		return;
199 
200 	rx_desc = isert_conn->conn_rx_descs;
201 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
202 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
203 				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
204 	}
205 
206 	kfree(isert_conn->conn_rx_descs);
207 	isert_conn->conn_rx_descs = NULL;
208 }
209 
210 static void isert_cq_tx_work(struct work_struct *);
211 static void isert_cq_tx_callback(struct ib_cq *, void *);
212 static void isert_cq_rx_work(struct work_struct *);
213 static void isert_cq_rx_callback(struct ib_cq *, void *);
214 
215 static int
216 isert_create_device_ib_res(struct isert_device *device)
217 {
218 	struct ib_device *ib_dev = device->ib_device;
219 	struct isert_cq_desc *cq_desc;
220 	struct ib_device_attr *dev_attr;
221 	int ret = 0, i, j;
222 
223 	dev_attr = &device->dev_attr;
224 	ret = isert_query_device(ib_dev, dev_attr);
225 	if (ret)
226 		return ret;
227 
228 	/* asign function handlers */
229 	if (dev_attr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) {
230 		device->use_fastreg = 1;
231 		device->reg_rdma_mem = isert_reg_rdma;
232 		device->unreg_rdma_mem = isert_unreg_rdma;
233 	} else {
234 		device->use_fastreg = 0;
235 		device->reg_rdma_mem = isert_map_rdma;
236 		device->unreg_rdma_mem = isert_unmap_cmd;
237 	}
238 
239 	device->cqs_used = min_t(int, num_online_cpus(),
240 				 device->ib_device->num_comp_vectors);
241 	device->cqs_used = min(ISERT_MAX_CQ, device->cqs_used);
242 	pr_debug("Using %d CQs, device %s supports %d vectors support "
243 		 "Fast registration %d\n",
244 		 device->cqs_used, device->ib_device->name,
245 		 device->ib_device->num_comp_vectors, device->use_fastreg);
246 	device->cq_desc = kzalloc(sizeof(struct isert_cq_desc) *
247 				device->cqs_used, GFP_KERNEL);
248 	if (!device->cq_desc) {
249 		pr_err("Unable to allocate device->cq_desc\n");
250 		return -ENOMEM;
251 	}
252 	cq_desc = device->cq_desc;
253 
254 	for (i = 0; i < device->cqs_used; i++) {
255 		cq_desc[i].device = device;
256 		cq_desc[i].cq_index = i;
257 
258 		INIT_WORK(&cq_desc[i].cq_rx_work, isert_cq_rx_work);
259 		device->dev_rx_cq[i] = ib_create_cq(device->ib_device,
260 						isert_cq_rx_callback,
261 						isert_cq_event_callback,
262 						(void *)&cq_desc[i],
263 						ISER_MAX_RX_CQ_LEN, i);
264 		if (IS_ERR(device->dev_rx_cq[i])) {
265 			ret = PTR_ERR(device->dev_rx_cq[i]);
266 			device->dev_rx_cq[i] = NULL;
267 			goto out_cq;
268 		}
269 
270 		INIT_WORK(&cq_desc[i].cq_tx_work, isert_cq_tx_work);
271 		device->dev_tx_cq[i] = ib_create_cq(device->ib_device,
272 						isert_cq_tx_callback,
273 						isert_cq_event_callback,
274 						(void *)&cq_desc[i],
275 						ISER_MAX_TX_CQ_LEN, i);
276 		if (IS_ERR(device->dev_tx_cq[i])) {
277 			ret = PTR_ERR(device->dev_tx_cq[i]);
278 			device->dev_tx_cq[i] = NULL;
279 			goto out_cq;
280 		}
281 
282 		ret = ib_req_notify_cq(device->dev_rx_cq[i], IB_CQ_NEXT_COMP);
283 		if (ret)
284 			goto out_cq;
285 
286 		ret = ib_req_notify_cq(device->dev_tx_cq[i], IB_CQ_NEXT_COMP);
287 		if (ret)
288 			goto out_cq;
289 	}
290 
291 	return 0;
292 
293 out_cq:
294 	for (j = 0; j < i; j++) {
295 		cq_desc = &device->cq_desc[j];
296 
297 		if (device->dev_rx_cq[j]) {
298 			cancel_work_sync(&cq_desc->cq_rx_work);
299 			ib_destroy_cq(device->dev_rx_cq[j]);
300 		}
301 		if (device->dev_tx_cq[j]) {
302 			cancel_work_sync(&cq_desc->cq_tx_work);
303 			ib_destroy_cq(device->dev_tx_cq[j]);
304 		}
305 	}
306 	kfree(device->cq_desc);
307 
308 	return ret;
309 }
310 
311 static void
312 isert_free_device_ib_res(struct isert_device *device)
313 {
314 	struct isert_cq_desc *cq_desc;
315 	int i;
316 
317 	for (i = 0; i < device->cqs_used; i++) {
318 		cq_desc = &device->cq_desc[i];
319 
320 		cancel_work_sync(&cq_desc->cq_rx_work);
321 		cancel_work_sync(&cq_desc->cq_tx_work);
322 		ib_destroy_cq(device->dev_rx_cq[i]);
323 		ib_destroy_cq(device->dev_tx_cq[i]);
324 		device->dev_rx_cq[i] = NULL;
325 		device->dev_tx_cq[i] = NULL;
326 	}
327 
328 	kfree(device->cq_desc);
329 }
330 
331 static void
332 isert_device_try_release(struct isert_device *device)
333 {
334 	mutex_lock(&device_list_mutex);
335 	device->refcount--;
336 	if (!device->refcount) {
337 		isert_free_device_ib_res(device);
338 		list_del(&device->dev_node);
339 		kfree(device);
340 	}
341 	mutex_unlock(&device_list_mutex);
342 }
343 
344 static struct isert_device *
345 isert_device_find_by_ib_dev(struct rdma_cm_id *cma_id)
346 {
347 	struct isert_device *device;
348 	int ret;
349 
350 	mutex_lock(&device_list_mutex);
351 	list_for_each_entry(device, &device_list, dev_node) {
352 		if (device->ib_device->node_guid == cma_id->device->node_guid) {
353 			device->refcount++;
354 			mutex_unlock(&device_list_mutex);
355 			return device;
356 		}
357 	}
358 
359 	device = kzalloc(sizeof(struct isert_device), GFP_KERNEL);
360 	if (!device) {
361 		mutex_unlock(&device_list_mutex);
362 		return ERR_PTR(-ENOMEM);
363 	}
364 
365 	INIT_LIST_HEAD(&device->dev_node);
366 
367 	device->ib_device = cma_id->device;
368 	ret = isert_create_device_ib_res(device);
369 	if (ret) {
370 		kfree(device);
371 		mutex_unlock(&device_list_mutex);
372 		return ERR_PTR(ret);
373 	}
374 
375 	device->refcount++;
376 	list_add_tail(&device->dev_node, &device_list);
377 	mutex_unlock(&device_list_mutex);
378 
379 	return device;
380 }
381 
382 static void
383 isert_conn_free_fastreg_pool(struct isert_conn *isert_conn)
384 {
385 	struct fast_reg_descriptor *fr_desc, *tmp;
386 	int i = 0;
387 
388 	if (list_empty(&isert_conn->conn_fr_pool))
389 		return;
390 
391 	pr_debug("Freeing conn %p fastreg pool", isert_conn);
392 
393 	list_for_each_entry_safe(fr_desc, tmp,
394 				 &isert_conn->conn_fr_pool, list) {
395 		list_del(&fr_desc->list);
396 		ib_free_fast_reg_page_list(fr_desc->data_frpl);
397 		ib_dereg_mr(fr_desc->data_mr);
398 		kfree(fr_desc);
399 		++i;
400 	}
401 
402 	if (i < isert_conn->conn_fr_pool_size)
403 		pr_warn("Pool still has %d regions registered\n",
404 			isert_conn->conn_fr_pool_size - i);
405 }
406 
407 static int
408 isert_create_fr_desc(struct ib_device *ib_device, struct ib_pd *pd,
409 		     struct fast_reg_descriptor *fr_desc)
410 {
411 	fr_desc->data_frpl = ib_alloc_fast_reg_page_list(ib_device,
412 							 ISCSI_ISER_SG_TABLESIZE);
413 	if (IS_ERR(fr_desc->data_frpl)) {
414 		pr_err("Failed to allocate data frpl err=%ld\n",
415 		       PTR_ERR(fr_desc->data_frpl));
416 		return PTR_ERR(fr_desc->data_frpl);
417 	}
418 
419 	fr_desc->data_mr = ib_alloc_fast_reg_mr(pd, ISCSI_ISER_SG_TABLESIZE);
420 	if (IS_ERR(fr_desc->data_mr)) {
421 		pr_err("Failed to allocate data frmr err=%ld\n",
422 		       PTR_ERR(fr_desc->data_mr));
423 		ib_free_fast_reg_page_list(fr_desc->data_frpl);
424 		return PTR_ERR(fr_desc->data_mr);
425 	}
426 	pr_debug("Create fr_desc %p page_list %p\n",
427 		 fr_desc, fr_desc->data_frpl->page_list);
428 
429 	fr_desc->valid = true;
430 
431 	return 0;
432 }
433 
434 static int
435 isert_conn_create_fastreg_pool(struct isert_conn *isert_conn)
436 {
437 	struct fast_reg_descriptor *fr_desc;
438 	struct isert_device *device = isert_conn->conn_device;
439 	int i, ret;
440 
441 	INIT_LIST_HEAD(&isert_conn->conn_fr_pool);
442 	isert_conn->conn_fr_pool_size = 0;
443 	for (i = 0; i < ISCSI_DEF_XMIT_CMDS_MAX; i++) {
444 		fr_desc = kzalloc(sizeof(*fr_desc), GFP_KERNEL);
445 		if (!fr_desc) {
446 			pr_err("Failed to allocate fast_reg descriptor\n");
447 			ret = -ENOMEM;
448 			goto err;
449 		}
450 
451 		ret = isert_create_fr_desc(device->ib_device,
452 					   isert_conn->conn_pd, fr_desc);
453 		if (ret) {
454 			pr_err("Failed to create fastreg descriptor err=%d\n",
455 			       ret);
456 			kfree(fr_desc);
457 			goto err;
458 		}
459 
460 		list_add_tail(&fr_desc->list, &isert_conn->conn_fr_pool);
461 		isert_conn->conn_fr_pool_size++;
462 	}
463 
464 	pr_debug("Creating conn %p fastreg pool size=%d",
465 		 isert_conn, isert_conn->conn_fr_pool_size);
466 
467 	return 0;
468 
469 err:
470 	isert_conn_free_fastreg_pool(isert_conn);
471 	return ret;
472 }
473 
474 static int
475 isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
476 {
477 	struct iscsi_np *np = cma_id->context;
478 	struct isert_np *isert_np = np->np_context;
479 	struct isert_conn *isert_conn;
480 	struct isert_device *device;
481 	struct ib_device *ib_dev = cma_id->device;
482 	int ret = 0;
483 
484 	pr_debug("Entering isert_connect_request cma_id: %p, context: %p\n",
485 		 cma_id, cma_id->context);
486 
487 	isert_conn = kzalloc(sizeof(struct isert_conn), GFP_KERNEL);
488 	if (!isert_conn) {
489 		pr_err("Unable to allocate isert_conn\n");
490 		return -ENOMEM;
491 	}
492 	isert_conn->state = ISER_CONN_INIT;
493 	INIT_LIST_HEAD(&isert_conn->conn_accept_node);
494 	init_completion(&isert_conn->conn_login_comp);
495 	init_completion(&isert_conn->conn_wait);
496 	init_completion(&isert_conn->conn_wait_comp_err);
497 	kref_init(&isert_conn->conn_kref);
498 	kref_get(&isert_conn->conn_kref);
499 	mutex_init(&isert_conn->conn_mutex);
500 	spin_lock_init(&isert_conn->conn_lock);
501 
502 	cma_id->context = isert_conn;
503 	isert_conn->conn_cm_id = cma_id;
504 	isert_conn->responder_resources = event->param.conn.responder_resources;
505 	isert_conn->initiator_depth = event->param.conn.initiator_depth;
506 	pr_debug("Using responder_resources: %u initiator_depth: %u\n",
507 		 isert_conn->responder_resources, isert_conn->initiator_depth);
508 
509 	isert_conn->login_buf = kzalloc(ISCSI_DEF_MAX_RECV_SEG_LEN +
510 					ISER_RX_LOGIN_SIZE, GFP_KERNEL);
511 	if (!isert_conn->login_buf) {
512 		pr_err("Unable to allocate isert_conn->login_buf\n");
513 		ret = -ENOMEM;
514 		goto out;
515 	}
516 
517 	isert_conn->login_req_buf = isert_conn->login_buf;
518 	isert_conn->login_rsp_buf = isert_conn->login_buf +
519 				    ISCSI_DEF_MAX_RECV_SEG_LEN;
520 	pr_debug("Set login_buf: %p login_req_buf: %p login_rsp_buf: %p\n",
521 		 isert_conn->login_buf, isert_conn->login_req_buf,
522 		 isert_conn->login_rsp_buf);
523 
524 	isert_conn->login_req_dma = ib_dma_map_single(ib_dev,
525 				(void *)isert_conn->login_req_buf,
526 				ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
527 
528 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_req_dma);
529 	if (ret) {
530 		pr_err("ib_dma_mapping_error failed for login_req_dma: %d\n",
531 		       ret);
532 		isert_conn->login_req_dma = 0;
533 		goto out_login_buf;
534 	}
535 
536 	isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
537 					(void *)isert_conn->login_rsp_buf,
538 					ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
539 
540 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
541 	if (ret) {
542 		pr_err("ib_dma_mapping_error failed for login_rsp_dma: %d\n",
543 		       ret);
544 		isert_conn->login_rsp_dma = 0;
545 		goto out_req_dma_map;
546 	}
547 
548 	device = isert_device_find_by_ib_dev(cma_id);
549 	if (IS_ERR(device)) {
550 		ret = PTR_ERR(device);
551 		goto out_rsp_dma_map;
552 	}
553 
554 	isert_conn->conn_device = device;
555 	isert_conn->conn_pd = ib_alloc_pd(isert_conn->conn_device->ib_device);
556 	if (IS_ERR(isert_conn->conn_pd)) {
557 		ret = PTR_ERR(isert_conn->conn_pd);
558 		pr_err("ib_alloc_pd failed for conn %p: ret=%d\n",
559 		       isert_conn, ret);
560 		goto out_pd;
561 	}
562 
563 	isert_conn->conn_mr = ib_get_dma_mr(isert_conn->conn_pd,
564 					   IB_ACCESS_LOCAL_WRITE);
565 	if (IS_ERR(isert_conn->conn_mr)) {
566 		ret = PTR_ERR(isert_conn->conn_mr);
567 		pr_err("ib_get_dma_mr failed for conn %p: ret=%d\n",
568 		       isert_conn, ret);
569 		goto out_mr;
570 	}
571 
572 	if (device->use_fastreg) {
573 		ret = isert_conn_create_fastreg_pool(isert_conn);
574 		if (ret) {
575 			pr_err("Conn: %p failed to create fastreg pool\n",
576 			       isert_conn);
577 			goto out_fastreg;
578 		}
579 	}
580 
581 	ret = isert_conn_setup_qp(isert_conn, cma_id);
582 	if (ret)
583 		goto out_conn_dev;
584 
585 	mutex_lock(&isert_np->np_accept_mutex);
586 	list_add_tail(&isert_np->np_accept_list, &isert_conn->conn_accept_node);
587 	mutex_unlock(&isert_np->np_accept_mutex);
588 
589 	pr_debug("isert_connect_request() waking up np_accept_wq: %p\n", np);
590 	wake_up(&isert_np->np_accept_wq);
591 	return 0;
592 
593 out_conn_dev:
594 	if (device->use_fastreg)
595 		isert_conn_free_fastreg_pool(isert_conn);
596 out_fastreg:
597 	ib_dereg_mr(isert_conn->conn_mr);
598 out_mr:
599 	ib_dealloc_pd(isert_conn->conn_pd);
600 out_pd:
601 	isert_device_try_release(device);
602 out_rsp_dma_map:
603 	ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
604 			    ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
605 out_req_dma_map:
606 	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
607 			    ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
608 out_login_buf:
609 	kfree(isert_conn->login_buf);
610 out:
611 	kfree(isert_conn);
612 	return ret;
613 }
614 
615 static void
616 isert_connect_release(struct isert_conn *isert_conn)
617 {
618 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
619 	struct isert_device *device = isert_conn->conn_device;
620 	int cq_index;
621 
622 	pr_debug("Entering isert_connect_release(): >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
623 
624 	if (device && device->use_fastreg)
625 		isert_conn_free_fastreg_pool(isert_conn);
626 
627 	if (isert_conn->conn_qp) {
628 		cq_index = ((struct isert_cq_desc *)
629 			isert_conn->conn_qp->recv_cq->cq_context)->cq_index;
630 		pr_debug("isert_connect_release: cq_index: %d\n", cq_index);
631 		isert_conn->conn_device->cq_active_qps[cq_index]--;
632 
633 		rdma_destroy_qp(isert_conn->conn_cm_id);
634 	}
635 
636 	isert_free_rx_descriptors(isert_conn);
637 	rdma_destroy_id(isert_conn->conn_cm_id);
638 
639 	ib_dereg_mr(isert_conn->conn_mr);
640 	ib_dealloc_pd(isert_conn->conn_pd);
641 
642 	if (isert_conn->login_buf) {
643 		ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
644 				    ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
645 		ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
646 				    ISCSI_DEF_MAX_RECV_SEG_LEN,
647 				    DMA_FROM_DEVICE);
648 		kfree(isert_conn->login_buf);
649 	}
650 	kfree(isert_conn);
651 
652 	if (device)
653 		isert_device_try_release(device);
654 
655 	pr_debug("Leaving isert_connect_release >>>>>>>>>>>>\n");
656 }
657 
658 static void
659 isert_connected_handler(struct rdma_cm_id *cma_id)
660 {
661 	return;
662 }
663 
664 static void
665 isert_release_conn_kref(struct kref *kref)
666 {
667 	struct isert_conn *isert_conn = container_of(kref,
668 				struct isert_conn, conn_kref);
669 
670 	pr_debug("Calling isert_connect_release for final kref %s/%d\n",
671 		 current->comm, current->pid);
672 
673 	isert_connect_release(isert_conn);
674 }
675 
676 static void
677 isert_put_conn(struct isert_conn *isert_conn)
678 {
679 	kref_put(&isert_conn->conn_kref, isert_release_conn_kref);
680 }
681 
682 static void
683 isert_disconnect_work(struct work_struct *work)
684 {
685 	struct isert_conn *isert_conn = container_of(work,
686 				struct isert_conn, conn_logout_work);
687 
688 	pr_debug("isert_disconnect_work(): >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
689 	mutex_lock(&isert_conn->conn_mutex);
690 	if (isert_conn->state == ISER_CONN_UP)
691 		isert_conn->state = ISER_CONN_TERMINATING;
692 
693 	if (isert_conn->post_recv_buf_count == 0 &&
694 	    atomic_read(&isert_conn->post_send_buf_count) == 0) {
695 		mutex_unlock(&isert_conn->conn_mutex);
696 		goto wake_up;
697 	}
698 	if (!isert_conn->conn_cm_id) {
699 		mutex_unlock(&isert_conn->conn_mutex);
700 		isert_put_conn(isert_conn);
701 		return;
702 	}
703 	if (!isert_conn->logout_posted) {
704 		pr_debug("Calling rdma_disconnect for !logout_posted from"
705 			 " isert_disconnect_work\n");
706 		rdma_disconnect(isert_conn->conn_cm_id);
707 		mutex_unlock(&isert_conn->conn_mutex);
708 		iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
709 		goto wake_up;
710 	}
711 	mutex_unlock(&isert_conn->conn_mutex);
712 
713 wake_up:
714 	complete(&isert_conn->conn_wait);
715 	isert_put_conn(isert_conn);
716 }
717 
718 static void
719 isert_disconnected_handler(struct rdma_cm_id *cma_id)
720 {
721 	struct isert_conn *isert_conn = (struct isert_conn *)cma_id->context;
722 
723 	INIT_WORK(&isert_conn->conn_logout_work, isert_disconnect_work);
724 	schedule_work(&isert_conn->conn_logout_work);
725 }
726 
727 static int
728 isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
729 {
730 	int ret = 0;
731 
732 	pr_debug("isert_cma_handler: event %d status %d conn %p id %p\n",
733 		 event->event, event->status, cma_id->context, cma_id);
734 
735 	switch (event->event) {
736 	case RDMA_CM_EVENT_CONNECT_REQUEST:
737 		pr_debug("RDMA_CM_EVENT_CONNECT_REQUEST: >>>>>>>>>>>>>>>\n");
738 		ret = isert_connect_request(cma_id, event);
739 		break;
740 	case RDMA_CM_EVENT_ESTABLISHED:
741 		pr_debug("RDMA_CM_EVENT_ESTABLISHED >>>>>>>>>>>>>>\n");
742 		isert_connected_handler(cma_id);
743 		break;
744 	case RDMA_CM_EVENT_DISCONNECTED:
745 		pr_debug("RDMA_CM_EVENT_DISCONNECTED: >>>>>>>>>>>>>>\n");
746 		isert_disconnected_handler(cma_id);
747 		break;
748 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
749 	case RDMA_CM_EVENT_ADDR_CHANGE:
750 		break;
751 	case RDMA_CM_EVENT_CONNECT_ERROR:
752 	default:
753 		pr_err("Unknown RDMA CMA event: %d\n", event->event);
754 		break;
755 	}
756 
757 	if (ret != 0) {
758 		pr_err("isert_cma_handler failed RDMA_CM_EVENT: 0x%08x %d\n",
759 		       event->event, ret);
760 		dump_stack();
761 	}
762 
763 	return ret;
764 }
765 
766 static int
767 isert_post_recv(struct isert_conn *isert_conn, u32 count)
768 {
769 	struct ib_recv_wr *rx_wr, *rx_wr_failed;
770 	int i, ret;
771 	unsigned int rx_head = isert_conn->conn_rx_desc_head;
772 	struct iser_rx_desc *rx_desc;
773 
774 	for (rx_wr = isert_conn->conn_rx_wr, i = 0; i < count; i++, rx_wr++) {
775 		rx_desc		= &isert_conn->conn_rx_descs[rx_head];
776 		rx_wr->wr_id	= (unsigned long)rx_desc;
777 		rx_wr->sg_list	= &rx_desc->rx_sg;
778 		rx_wr->num_sge	= 1;
779 		rx_wr->next	= rx_wr + 1;
780 		rx_head = (rx_head + 1) & (ISERT_QP_MAX_RECV_DTOS - 1);
781 	}
782 
783 	rx_wr--;
784 	rx_wr->next = NULL; /* mark end of work requests list */
785 
786 	isert_conn->post_recv_buf_count += count;
787 	ret = ib_post_recv(isert_conn->conn_qp, isert_conn->conn_rx_wr,
788 				&rx_wr_failed);
789 	if (ret) {
790 		pr_err("ib_post_recv() failed with ret: %d\n", ret);
791 		isert_conn->post_recv_buf_count -= count;
792 	} else {
793 		pr_debug("isert_post_recv(): Posted %d RX buffers\n", count);
794 		isert_conn->conn_rx_desc_head = rx_head;
795 	}
796 	return ret;
797 }
798 
799 static int
800 isert_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
801 {
802 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
803 	struct ib_send_wr send_wr, *send_wr_failed;
804 	int ret;
805 
806 	ib_dma_sync_single_for_device(ib_dev, tx_desc->dma_addr,
807 				      ISER_HEADERS_LEN, DMA_TO_DEVICE);
808 
809 	send_wr.next	= NULL;
810 	send_wr.wr_id	= (unsigned long)tx_desc;
811 	send_wr.sg_list	= tx_desc->tx_sg;
812 	send_wr.num_sge	= tx_desc->num_sge;
813 	send_wr.opcode	= IB_WR_SEND;
814 	send_wr.send_flags = IB_SEND_SIGNALED;
815 
816 	atomic_inc(&isert_conn->post_send_buf_count);
817 
818 	ret = ib_post_send(isert_conn->conn_qp, &send_wr, &send_wr_failed);
819 	if (ret) {
820 		pr_err("ib_post_send() failed, ret: %d\n", ret);
821 		atomic_dec(&isert_conn->post_send_buf_count);
822 	}
823 
824 	return ret;
825 }
826 
827 static void
828 isert_create_send_desc(struct isert_conn *isert_conn,
829 		       struct isert_cmd *isert_cmd,
830 		       struct iser_tx_desc *tx_desc)
831 {
832 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
833 
834 	ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr,
835 				   ISER_HEADERS_LEN, DMA_TO_DEVICE);
836 
837 	memset(&tx_desc->iser_header, 0, sizeof(struct iser_hdr));
838 	tx_desc->iser_header.flags = ISER_VER;
839 
840 	tx_desc->num_sge = 1;
841 	tx_desc->isert_cmd = isert_cmd;
842 
843 	if (tx_desc->tx_sg[0].lkey != isert_conn->conn_mr->lkey) {
844 		tx_desc->tx_sg[0].lkey = isert_conn->conn_mr->lkey;
845 		pr_debug("tx_desc %p lkey mismatch, fixing\n", tx_desc);
846 	}
847 }
848 
849 static int
850 isert_init_tx_hdrs(struct isert_conn *isert_conn,
851 		   struct iser_tx_desc *tx_desc)
852 {
853 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
854 	u64 dma_addr;
855 
856 	dma_addr = ib_dma_map_single(ib_dev, (void *)tx_desc,
857 			ISER_HEADERS_LEN, DMA_TO_DEVICE);
858 	if (ib_dma_mapping_error(ib_dev, dma_addr)) {
859 		pr_err("ib_dma_mapping_error() failed\n");
860 		return -ENOMEM;
861 	}
862 
863 	tx_desc->dma_addr = dma_addr;
864 	tx_desc->tx_sg[0].addr	= tx_desc->dma_addr;
865 	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
866 	tx_desc->tx_sg[0].lkey = isert_conn->conn_mr->lkey;
867 
868 	pr_debug("isert_init_tx_hdrs: Setup tx_sg[0].addr: 0x%llx length: %u"
869 		 " lkey: 0x%08x\n", tx_desc->tx_sg[0].addr,
870 		 tx_desc->tx_sg[0].length, tx_desc->tx_sg[0].lkey);
871 
872 	return 0;
873 }
874 
875 static void
876 isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
877 		   struct ib_send_wr *send_wr, bool coalesce)
878 {
879 	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
880 
881 	isert_cmd->rdma_wr.iser_ib_op = ISER_IB_SEND;
882 	send_wr->wr_id = (unsigned long)&isert_cmd->tx_desc;
883 	send_wr->opcode = IB_WR_SEND;
884 	send_wr->sg_list = &tx_desc->tx_sg[0];
885 	send_wr->num_sge = isert_cmd->tx_desc.num_sge;
886 	/*
887 	 * Coalesce send completion interrupts by only setting IB_SEND_SIGNALED
888 	 * bit for every ISERT_COMP_BATCH_COUNT number of ib_post_send() calls.
889 	 */
890 	mutex_lock(&isert_conn->conn_mutex);
891 	if (coalesce && isert_conn->state == ISER_CONN_UP &&
892 	    ++isert_conn->conn_comp_batch < ISERT_COMP_BATCH_COUNT) {
893 		tx_desc->llnode_active = true;
894 		llist_add(&tx_desc->comp_llnode, &isert_conn->conn_comp_llist);
895 		mutex_unlock(&isert_conn->conn_mutex);
896 		return;
897 	}
898 	isert_conn->conn_comp_batch = 0;
899 	tx_desc->comp_llnode_batch = llist_del_all(&isert_conn->conn_comp_llist);
900 	mutex_unlock(&isert_conn->conn_mutex);
901 
902 	send_wr->send_flags = IB_SEND_SIGNALED;
903 }
904 
905 static int
906 isert_rdma_post_recvl(struct isert_conn *isert_conn)
907 {
908 	struct ib_recv_wr rx_wr, *rx_wr_fail;
909 	struct ib_sge sge;
910 	int ret;
911 
912 	memset(&sge, 0, sizeof(struct ib_sge));
913 	sge.addr = isert_conn->login_req_dma;
914 	sge.length = ISER_RX_LOGIN_SIZE;
915 	sge.lkey = isert_conn->conn_mr->lkey;
916 
917 	pr_debug("Setup sge: addr: %llx length: %d 0x%08x\n",
918 		sge.addr, sge.length, sge.lkey);
919 
920 	memset(&rx_wr, 0, sizeof(struct ib_recv_wr));
921 	rx_wr.wr_id = (unsigned long)isert_conn->login_req_buf;
922 	rx_wr.sg_list = &sge;
923 	rx_wr.num_sge = 1;
924 
925 	isert_conn->post_recv_buf_count++;
926 	ret = ib_post_recv(isert_conn->conn_qp, &rx_wr, &rx_wr_fail);
927 	if (ret) {
928 		pr_err("ib_post_recv() failed: %d\n", ret);
929 		isert_conn->post_recv_buf_count--;
930 	}
931 
932 	pr_debug("ib_post_recv(): returned success >>>>>>>>>>>>>>>>>>>>>>>>\n");
933 	return ret;
934 }
935 
936 static int
937 isert_put_login_tx(struct iscsi_conn *conn, struct iscsi_login *login,
938 		   u32 length)
939 {
940 	struct isert_conn *isert_conn = conn->context;
941 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
942 	struct iser_tx_desc *tx_desc = &isert_conn->conn_login_tx_desc;
943 	int ret;
944 
945 	isert_create_send_desc(isert_conn, NULL, tx_desc);
946 
947 	memcpy(&tx_desc->iscsi_header, &login->rsp[0],
948 	       sizeof(struct iscsi_hdr));
949 
950 	isert_init_tx_hdrs(isert_conn, tx_desc);
951 
952 	if (length > 0) {
953 		struct ib_sge *tx_dsg = &tx_desc->tx_sg[1];
954 
955 		ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_rsp_dma,
956 					   length, DMA_TO_DEVICE);
957 
958 		memcpy(isert_conn->login_rsp_buf, login->rsp_buf, length);
959 
960 		ib_dma_sync_single_for_device(ib_dev, isert_conn->login_rsp_dma,
961 					      length, DMA_TO_DEVICE);
962 
963 		tx_dsg->addr	= isert_conn->login_rsp_dma;
964 		tx_dsg->length	= length;
965 		tx_dsg->lkey	= isert_conn->conn_mr->lkey;
966 		tx_desc->num_sge = 2;
967 	}
968 	if (!login->login_failed) {
969 		if (login->login_complete) {
970 			ret = isert_alloc_rx_descriptors(isert_conn);
971 			if (ret)
972 				return ret;
973 
974 			ret = isert_post_recv(isert_conn, ISERT_MIN_POSTED_RX);
975 			if (ret)
976 				return ret;
977 
978 			isert_conn->state = ISER_CONN_UP;
979 			goto post_send;
980 		}
981 
982 		ret = isert_rdma_post_recvl(isert_conn);
983 		if (ret)
984 			return ret;
985 	}
986 post_send:
987 	ret = isert_post_send(isert_conn, tx_desc);
988 	if (ret)
989 		return ret;
990 
991 	return 0;
992 }
993 
994 static void
995 isert_rx_login_req(struct iser_rx_desc *rx_desc, int rx_buflen,
996 		   struct isert_conn *isert_conn)
997 {
998 	struct iscsi_conn *conn = isert_conn->conn;
999 	struct iscsi_login *login = conn->conn_login;
1000 	int size;
1001 
1002 	if (!login) {
1003 		pr_err("conn->conn_login is NULL\n");
1004 		dump_stack();
1005 		return;
1006 	}
1007 
1008 	if (login->first_request) {
1009 		struct iscsi_login_req *login_req =
1010 			(struct iscsi_login_req *)&rx_desc->iscsi_header;
1011 		/*
1012 		 * Setup the initial iscsi_login values from the leading
1013 		 * login request PDU.
1014 		 */
1015 		login->leading_connection = (!login_req->tsih) ? 1 : 0;
1016 		login->current_stage =
1017 			(login_req->flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK)
1018 			 >> 2;
1019 		login->version_min	= login_req->min_version;
1020 		login->version_max	= login_req->max_version;
1021 		memcpy(login->isid, login_req->isid, 6);
1022 		login->cmd_sn		= be32_to_cpu(login_req->cmdsn);
1023 		login->init_task_tag	= login_req->itt;
1024 		login->initial_exp_statsn = be32_to_cpu(login_req->exp_statsn);
1025 		login->cid		= be16_to_cpu(login_req->cid);
1026 		login->tsih		= be16_to_cpu(login_req->tsih);
1027 	}
1028 
1029 	memcpy(&login->req[0], (void *)&rx_desc->iscsi_header, ISCSI_HDR_LEN);
1030 
1031 	size = min(rx_buflen, MAX_KEY_VALUE_PAIRS);
1032 	pr_debug("Using login payload size: %d, rx_buflen: %d MAX_KEY_VALUE_PAIRS: %d\n",
1033 		 size, rx_buflen, MAX_KEY_VALUE_PAIRS);
1034 	memcpy(login->req_buf, &rx_desc->data[0], size);
1035 
1036 	if (login->first_request) {
1037 		complete(&isert_conn->conn_login_comp);
1038 		return;
1039 	}
1040 	schedule_delayed_work(&conn->login_work, 0);
1041 }
1042 
1043 static struct iscsi_cmd
1044 *isert_allocate_cmd(struct iscsi_conn *conn)
1045 {
1046 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1047 	struct isert_cmd *isert_cmd;
1048 	struct iscsi_cmd *cmd;
1049 
1050 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
1051 	if (!cmd) {
1052 		pr_err("Unable to allocate iscsi_cmd + isert_cmd\n");
1053 		return NULL;
1054 	}
1055 	isert_cmd = iscsit_priv_cmd(cmd);
1056 	isert_cmd->conn = isert_conn;
1057 	isert_cmd->iscsi_cmd = cmd;
1058 
1059 	return cmd;
1060 }
1061 
1062 static int
1063 isert_handle_scsi_cmd(struct isert_conn *isert_conn,
1064 		      struct isert_cmd *isert_cmd, struct iscsi_cmd *cmd,
1065 		      struct iser_rx_desc *rx_desc, unsigned char *buf)
1066 {
1067 	struct iscsi_conn *conn = isert_conn->conn;
1068 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1069 	struct scatterlist *sg;
1070 	int imm_data, imm_data_len, unsol_data, sg_nents, rc;
1071 	bool dump_payload = false;
1072 
1073 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1074 	if (rc < 0)
1075 		return rc;
1076 
1077 	imm_data = cmd->immediate_data;
1078 	imm_data_len = cmd->first_burst_len;
1079 	unsol_data = cmd->unsolicited_data;
1080 
1081 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1082 	if (rc < 0) {
1083 		return 0;
1084 	} else if (rc > 0) {
1085 		dump_payload = true;
1086 		goto sequence_cmd;
1087 	}
1088 
1089 	if (!imm_data)
1090 		return 0;
1091 
1092 	sg = &cmd->se_cmd.t_data_sg[0];
1093 	sg_nents = max(1UL, DIV_ROUND_UP(imm_data_len, PAGE_SIZE));
1094 
1095 	pr_debug("Copying Immediate SG: %p sg_nents: %u from %p imm_data_len: %d\n",
1096 		 sg, sg_nents, &rx_desc->data[0], imm_data_len);
1097 
1098 	sg_copy_from_buffer(sg, sg_nents, &rx_desc->data[0], imm_data_len);
1099 
1100 	cmd->write_data_done += imm_data_len;
1101 
1102 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
1103 		spin_lock_bh(&cmd->istate_lock);
1104 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1105 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1106 		spin_unlock_bh(&cmd->istate_lock);
1107 	}
1108 
1109 sequence_cmd:
1110 	rc = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1111 
1112 	if (!rc && dump_payload == false && unsol_data)
1113 		iscsit_set_unsoliticed_dataout(cmd);
1114 
1115 	return 0;
1116 }
1117 
1118 static int
1119 isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
1120 			   struct iser_rx_desc *rx_desc, unsigned char *buf)
1121 {
1122 	struct scatterlist *sg_start;
1123 	struct iscsi_conn *conn = isert_conn->conn;
1124 	struct iscsi_cmd *cmd = NULL;
1125 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1126 	u32 unsol_data_len = ntoh24(hdr->dlength);
1127 	int rc, sg_nents, sg_off, page_off;
1128 
1129 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1130 	if (rc < 0)
1131 		return rc;
1132 	else if (!cmd)
1133 		return 0;
1134 	/*
1135 	 * FIXME: Unexpected unsolicited_data out
1136 	 */
1137 	if (!cmd->unsolicited_data) {
1138 		pr_err("Received unexpected solicited data payload\n");
1139 		dump_stack();
1140 		return -1;
1141 	}
1142 
1143 	pr_debug("Unsolicited DataOut unsol_data_len: %u, write_data_done: %u, data_length: %u\n",
1144 		 unsol_data_len, cmd->write_data_done, cmd->se_cmd.data_length);
1145 
1146 	sg_off = cmd->write_data_done / PAGE_SIZE;
1147 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
1148 	sg_nents = max(1UL, DIV_ROUND_UP(unsol_data_len, PAGE_SIZE));
1149 	page_off = cmd->write_data_done % PAGE_SIZE;
1150 	/*
1151 	 * FIXME: Non page-aligned unsolicited_data out
1152 	 */
1153 	if (page_off) {
1154 		pr_err("Received unexpected non-page aligned data payload\n");
1155 		dump_stack();
1156 		return -1;
1157 	}
1158 	pr_debug("Copying DataOut: sg_start: %p, sg_off: %u sg_nents: %u from %p %u\n",
1159 		 sg_start, sg_off, sg_nents, &rx_desc->data[0], unsol_data_len);
1160 
1161 	sg_copy_from_buffer(sg_start, sg_nents, &rx_desc->data[0],
1162 			    unsol_data_len);
1163 
1164 	rc = iscsit_check_dataout_payload(cmd, hdr, false);
1165 	if (rc < 0)
1166 		return rc;
1167 
1168 	return 0;
1169 }
1170 
1171 static int
1172 isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1173 		     struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1174 		     unsigned char *buf)
1175 {
1176 	struct iscsi_conn *conn = isert_conn->conn;
1177 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1178 	int rc;
1179 
1180 	rc = iscsit_setup_nop_out(conn, cmd, hdr);
1181 	if (rc < 0)
1182 		return rc;
1183 	/*
1184 	 * FIXME: Add support for NOPOUT payload using unsolicited RDMA payload
1185 	 */
1186 
1187 	return iscsit_process_nop_out(conn, cmd, hdr);
1188 }
1189 
1190 static int
1191 isert_handle_text_cmd(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1192 		      struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1193 		      struct iscsi_text *hdr)
1194 {
1195 	struct iscsi_conn *conn = isert_conn->conn;
1196 	u32 payload_length = ntoh24(hdr->dlength);
1197 	int rc;
1198 	unsigned char *text_in;
1199 
1200 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
1201 	if (rc < 0)
1202 		return rc;
1203 
1204 	text_in = kzalloc(payload_length, GFP_KERNEL);
1205 	if (!text_in) {
1206 		pr_err("Unable to allocate text_in of payload_length: %u\n",
1207 		       payload_length);
1208 		return -ENOMEM;
1209 	}
1210 	cmd->text_in_ptr = text_in;
1211 
1212 	memcpy(cmd->text_in_ptr, &rx_desc->data[0], payload_length);
1213 
1214 	return iscsit_process_text_cmd(conn, cmd, hdr);
1215 }
1216 
1217 static int
1218 isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
1219 		uint32_t read_stag, uint64_t read_va,
1220 		uint32_t write_stag, uint64_t write_va)
1221 {
1222 	struct iscsi_hdr *hdr = &rx_desc->iscsi_header;
1223 	struct iscsi_conn *conn = isert_conn->conn;
1224 	struct iscsi_session *sess = conn->sess;
1225 	struct iscsi_cmd *cmd;
1226 	struct isert_cmd *isert_cmd;
1227 	int ret = -EINVAL;
1228 	u8 opcode = (hdr->opcode & ISCSI_OPCODE_MASK);
1229 
1230 	if (sess->sess_ops->SessionType &&
1231 	   (!(opcode & ISCSI_OP_TEXT) || !(opcode & ISCSI_OP_LOGOUT))) {
1232 		pr_err("Got illegal opcode: 0x%02x in SessionType=Discovery,"
1233 		       " ignoring\n", opcode);
1234 		return 0;
1235 	}
1236 
1237 	switch (opcode) {
1238 	case ISCSI_OP_SCSI_CMD:
1239 		cmd = isert_allocate_cmd(conn);
1240 		if (!cmd)
1241 			break;
1242 
1243 		isert_cmd = iscsit_priv_cmd(cmd);
1244 		isert_cmd->read_stag = read_stag;
1245 		isert_cmd->read_va = read_va;
1246 		isert_cmd->write_stag = write_stag;
1247 		isert_cmd->write_va = write_va;
1248 
1249 		ret = isert_handle_scsi_cmd(isert_conn, isert_cmd, cmd,
1250 					rx_desc, (unsigned char *)hdr);
1251 		break;
1252 	case ISCSI_OP_NOOP_OUT:
1253 		cmd = isert_allocate_cmd(conn);
1254 		if (!cmd)
1255 			break;
1256 
1257 		isert_cmd = iscsit_priv_cmd(cmd);
1258 		ret = isert_handle_nop_out(isert_conn, isert_cmd, cmd,
1259 					   rx_desc, (unsigned char *)hdr);
1260 		break;
1261 	case ISCSI_OP_SCSI_DATA_OUT:
1262 		ret = isert_handle_iscsi_dataout(isert_conn, rx_desc,
1263 						(unsigned char *)hdr);
1264 		break;
1265 	case ISCSI_OP_SCSI_TMFUNC:
1266 		cmd = isert_allocate_cmd(conn);
1267 		if (!cmd)
1268 			break;
1269 
1270 		ret = iscsit_handle_task_mgt_cmd(conn, cmd,
1271 						(unsigned char *)hdr);
1272 		break;
1273 	case ISCSI_OP_LOGOUT:
1274 		cmd = isert_allocate_cmd(conn);
1275 		if (!cmd)
1276 			break;
1277 
1278 		ret = iscsit_handle_logout_cmd(conn, cmd, (unsigned char *)hdr);
1279 		if (ret > 0)
1280 			wait_for_completion_timeout(&conn->conn_logout_comp,
1281 						    SECONDS_FOR_LOGOUT_COMP *
1282 						    HZ);
1283 		break;
1284 	case ISCSI_OP_TEXT:
1285 		cmd = isert_allocate_cmd(conn);
1286 		if (!cmd)
1287 			break;
1288 
1289 		isert_cmd = iscsit_priv_cmd(cmd);
1290 		ret = isert_handle_text_cmd(isert_conn, isert_cmd, cmd,
1291 					    rx_desc, (struct iscsi_text *)hdr);
1292 		break;
1293 	default:
1294 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", opcode);
1295 		dump_stack();
1296 		break;
1297 	}
1298 
1299 	return ret;
1300 }
1301 
1302 static void
1303 isert_rx_do_work(struct iser_rx_desc *rx_desc, struct isert_conn *isert_conn)
1304 {
1305 	struct iser_hdr *iser_hdr = &rx_desc->iser_header;
1306 	uint64_t read_va = 0, write_va = 0;
1307 	uint32_t read_stag = 0, write_stag = 0;
1308 	int rc;
1309 
1310 	switch (iser_hdr->flags & 0xF0) {
1311 	case ISCSI_CTRL:
1312 		if (iser_hdr->flags & ISER_RSV) {
1313 			read_stag = be32_to_cpu(iser_hdr->read_stag);
1314 			read_va = be64_to_cpu(iser_hdr->read_va);
1315 			pr_debug("ISER_RSV: read_stag: 0x%08x read_va: 0x%16llx\n",
1316 				 read_stag, (unsigned long long)read_va);
1317 		}
1318 		if (iser_hdr->flags & ISER_WSV) {
1319 			write_stag = be32_to_cpu(iser_hdr->write_stag);
1320 			write_va = be64_to_cpu(iser_hdr->write_va);
1321 			pr_debug("ISER_WSV: write__stag: 0x%08x write_va: 0x%16llx\n",
1322 				 write_stag, (unsigned long long)write_va);
1323 		}
1324 
1325 		pr_debug("ISER ISCSI_CTRL PDU\n");
1326 		break;
1327 	case ISER_HELLO:
1328 		pr_err("iSER Hello message\n");
1329 		break;
1330 	default:
1331 		pr_warn("Unknown iSER hdr flags: 0x%02x\n", iser_hdr->flags);
1332 		break;
1333 	}
1334 
1335 	rc = isert_rx_opcode(isert_conn, rx_desc,
1336 			     read_stag, read_va, write_stag, write_va);
1337 }
1338 
1339 static void
1340 isert_rx_completion(struct iser_rx_desc *desc, struct isert_conn *isert_conn,
1341 		    unsigned long xfer_len)
1342 {
1343 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1344 	struct iscsi_hdr *hdr;
1345 	u64 rx_dma;
1346 	int rx_buflen, outstanding;
1347 
1348 	if ((char *)desc == isert_conn->login_req_buf) {
1349 		rx_dma = isert_conn->login_req_dma;
1350 		rx_buflen = ISER_RX_LOGIN_SIZE;
1351 		pr_debug("ISER login_buf: Using rx_dma: 0x%llx, rx_buflen: %d\n",
1352 			 rx_dma, rx_buflen);
1353 	} else {
1354 		rx_dma = desc->dma_addr;
1355 		rx_buflen = ISER_RX_PAYLOAD_SIZE;
1356 		pr_debug("ISER req_buf: Using rx_dma: 0x%llx, rx_buflen: %d\n",
1357 			 rx_dma, rx_buflen);
1358 	}
1359 
1360 	ib_dma_sync_single_for_cpu(ib_dev, rx_dma, rx_buflen, DMA_FROM_DEVICE);
1361 
1362 	hdr = &desc->iscsi_header;
1363 	pr_debug("iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n",
1364 		 hdr->opcode, hdr->itt, hdr->flags,
1365 		 (int)(xfer_len - ISER_HEADERS_LEN));
1366 
1367 	if ((char *)desc == isert_conn->login_req_buf)
1368 		isert_rx_login_req(desc, xfer_len - ISER_HEADERS_LEN,
1369 				   isert_conn);
1370 	else
1371 		isert_rx_do_work(desc, isert_conn);
1372 
1373 	ib_dma_sync_single_for_device(ib_dev, rx_dma, rx_buflen,
1374 				      DMA_FROM_DEVICE);
1375 
1376 	isert_conn->post_recv_buf_count--;
1377 	pr_debug("iSERT: Decremented post_recv_buf_count: %d\n",
1378 		 isert_conn->post_recv_buf_count);
1379 
1380 	if ((char *)desc == isert_conn->login_req_buf)
1381 		return;
1382 
1383 	outstanding = isert_conn->post_recv_buf_count;
1384 	if (outstanding + ISERT_MIN_POSTED_RX <= ISERT_QP_MAX_RECV_DTOS) {
1385 		int err, count = min(ISERT_QP_MAX_RECV_DTOS - outstanding,
1386 				ISERT_MIN_POSTED_RX);
1387 		err = isert_post_recv(isert_conn, count);
1388 		if (err) {
1389 			pr_err("isert_post_recv() count: %d failed, %d\n",
1390 			       count, err);
1391 		}
1392 	}
1393 }
1394 
1395 static void
1396 isert_unmap_cmd(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn)
1397 {
1398 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1399 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1400 
1401 	pr_debug("isert_unmap_cmd: %p\n", isert_cmd);
1402 	if (wr->sge) {
1403 		pr_debug("isert_unmap_cmd: %p unmap_sg op\n", isert_cmd);
1404 		ib_dma_unmap_sg(ib_dev, wr->sge, wr->num_sge,
1405 				(wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
1406 				DMA_TO_DEVICE : DMA_FROM_DEVICE);
1407 		wr->sge = NULL;
1408 	}
1409 
1410 	if (wr->send_wr) {
1411 		pr_debug("isert_unmap_cmd: %p free send_wr\n", isert_cmd);
1412 		kfree(wr->send_wr);
1413 		wr->send_wr = NULL;
1414 	}
1415 
1416 	if (wr->ib_sge) {
1417 		pr_debug("isert_unmap_cmd: %p free ib_sge\n", isert_cmd);
1418 		kfree(wr->ib_sge);
1419 		wr->ib_sge = NULL;
1420 	}
1421 }
1422 
1423 static void
1424 isert_unreg_rdma(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn)
1425 {
1426 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1427 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1428 	LIST_HEAD(unmap_list);
1429 
1430 	pr_debug("unreg_fastreg_cmd: %p\n", isert_cmd);
1431 
1432 	if (wr->fr_desc) {
1433 		pr_debug("unreg_fastreg_cmd: %p free fr_desc %p\n",
1434 			 isert_cmd, wr->fr_desc);
1435 		spin_lock_bh(&isert_conn->conn_lock);
1436 		list_add_tail(&wr->fr_desc->list, &isert_conn->conn_fr_pool);
1437 		spin_unlock_bh(&isert_conn->conn_lock);
1438 		wr->fr_desc = NULL;
1439 	}
1440 
1441 	if (wr->sge) {
1442 		pr_debug("unreg_fastreg_cmd: %p unmap_sg op\n", isert_cmd);
1443 		ib_dma_unmap_sg(ib_dev, wr->sge, wr->num_sge,
1444 				(wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
1445 				DMA_TO_DEVICE : DMA_FROM_DEVICE);
1446 		wr->sge = NULL;
1447 	}
1448 
1449 	wr->ib_sge = NULL;
1450 	wr->send_wr = NULL;
1451 }
1452 
1453 static void
1454 isert_put_cmd(struct isert_cmd *isert_cmd)
1455 {
1456 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1457 	struct isert_conn *isert_conn = isert_cmd->conn;
1458 	struct iscsi_conn *conn = isert_conn->conn;
1459 	struct isert_device *device = isert_conn->conn_device;
1460 
1461 	pr_debug("Entering isert_put_cmd: %p\n", isert_cmd);
1462 
1463 	switch (cmd->iscsi_opcode) {
1464 	case ISCSI_OP_SCSI_CMD:
1465 		spin_lock_bh(&conn->cmd_lock);
1466 		if (!list_empty(&cmd->i_conn_node))
1467 			list_del_init(&cmd->i_conn_node);
1468 		spin_unlock_bh(&conn->cmd_lock);
1469 
1470 		if (cmd->data_direction == DMA_TO_DEVICE)
1471 			iscsit_stop_dataout_timer(cmd);
1472 
1473 		device->unreg_rdma_mem(isert_cmd, isert_conn);
1474 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1475 		break;
1476 	case ISCSI_OP_SCSI_TMFUNC:
1477 		spin_lock_bh(&conn->cmd_lock);
1478 		if (!list_empty(&cmd->i_conn_node))
1479 			list_del_init(&cmd->i_conn_node);
1480 		spin_unlock_bh(&conn->cmd_lock);
1481 
1482 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1483 		break;
1484 	case ISCSI_OP_REJECT:
1485 	case ISCSI_OP_NOOP_OUT:
1486 	case ISCSI_OP_TEXT:
1487 		spin_lock_bh(&conn->cmd_lock);
1488 		if (!list_empty(&cmd->i_conn_node))
1489 			list_del_init(&cmd->i_conn_node);
1490 		spin_unlock_bh(&conn->cmd_lock);
1491 
1492 		/*
1493 		 * Handle special case for REJECT when iscsi_add_reject*() has
1494 		 * overwritten the original iscsi_opcode assignment, and the
1495 		 * associated cmd->se_cmd needs to be released.
1496 		 */
1497 		if (cmd->se_cmd.se_tfo != NULL) {
1498 			pr_debug("Calling transport_generic_free_cmd from"
1499 				 " isert_put_cmd for 0x%02x\n",
1500 				 cmd->iscsi_opcode);
1501 			transport_generic_free_cmd(&cmd->se_cmd, 0);
1502 			break;
1503 		}
1504 		/*
1505 		 * Fall-through
1506 		 */
1507 	default:
1508 		iscsit_release_cmd(cmd);
1509 		break;
1510 	}
1511 }
1512 
1513 static void
1514 isert_unmap_tx_desc(struct iser_tx_desc *tx_desc, struct ib_device *ib_dev)
1515 {
1516 	if (tx_desc->dma_addr != 0) {
1517 		pr_debug("Calling ib_dma_unmap_single for tx_desc->dma_addr\n");
1518 		ib_dma_unmap_single(ib_dev, tx_desc->dma_addr,
1519 				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
1520 		tx_desc->dma_addr = 0;
1521 	}
1522 }
1523 
1524 static void
1525 isert_completion_put(struct iser_tx_desc *tx_desc, struct isert_cmd *isert_cmd,
1526 		     struct ib_device *ib_dev)
1527 {
1528 	if (isert_cmd->pdu_buf_dma != 0) {
1529 		pr_debug("Calling ib_dma_unmap_single for isert_cmd->pdu_buf_dma\n");
1530 		ib_dma_unmap_single(ib_dev, isert_cmd->pdu_buf_dma,
1531 				    isert_cmd->pdu_buf_len, DMA_TO_DEVICE);
1532 		isert_cmd->pdu_buf_dma = 0;
1533 	}
1534 
1535 	isert_unmap_tx_desc(tx_desc, ib_dev);
1536 	isert_put_cmd(isert_cmd);
1537 }
1538 
1539 static void
1540 isert_completion_rdma_read(struct iser_tx_desc *tx_desc,
1541 			   struct isert_cmd *isert_cmd)
1542 {
1543 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1544 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1545 	struct se_cmd *se_cmd = &cmd->se_cmd;
1546 	struct isert_conn *isert_conn = isert_cmd->conn;
1547 	struct isert_device *device = isert_conn->conn_device;
1548 
1549 	iscsit_stop_dataout_timer(cmd);
1550 	device->unreg_rdma_mem(isert_cmd, isert_conn);
1551 	cmd->write_data_done = wr->cur_rdma_length;
1552 	wr->send_wr_num = 0;
1553 
1554 	pr_debug("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
1555 	spin_lock_bh(&cmd->istate_lock);
1556 	cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1557 	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1558 	spin_unlock_bh(&cmd->istate_lock);
1559 
1560 	target_execute_cmd(se_cmd);
1561 }
1562 
1563 static void
1564 isert_do_control_comp(struct work_struct *work)
1565 {
1566 	struct isert_cmd *isert_cmd = container_of(work,
1567 			struct isert_cmd, comp_work);
1568 	struct isert_conn *isert_conn = isert_cmd->conn;
1569 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1570 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1571 
1572 	switch (cmd->i_state) {
1573 	case ISTATE_SEND_TASKMGTRSP:
1574 		pr_debug("Calling iscsit_tmr_post_handler >>>>>>>>>>>>>>>>>\n");
1575 
1576 		atomic_dec(&isert_conn->post_send_buf_count);
1577 		iscsit_tmr_post_handler(cmd, cmd->conn);
1578 
1579 		cmd->i_state = ISTATE_SENT_STATUS;
1580 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd, ib_dev);
1581 		break;
1582 	case ISTATE_SEND_REJECT:
1583 		pr_debug("Got isert_do_control_comp ISTATE_SEND_REJECT: >>>\n");
1584 		atomic_dec(&isert_conn->post_send_buf_count);
1585 
1586 		cmd->i_state = ISTATE_SENT_STATUS;
1587 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd, ib_dev);
1588 		break;
1589 	case ISTATE_SEND_LOGOUTRSP:
1590 		pr_debug("Calling iscsit_logout_post_handler >>>>>>>>>>>>>>\n");
1591 		/*
1592 		 * Call atomic_dec(&isert_conn->post_send_buf_count)
1593 		 * from isert_wait_conn()
1594 		 */
1595 		isert_conn->logout_posted = true;
1596 		iscsit_logout_post_handler(cmd, cmd->conn);
1597 		break;
1598 	case ISTATE_SEND_TEXTRSP:
1599 		atomic_dec(&isert_conn->post_send_buf_count);
1600 		cmd->i_state = ISTATE_SENT_STATUS;
1601 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd, ib_dev);
1602 		break;
1603 	default:
1604 		pr_err("Unknown do_control_comp i_state %d\n", cmd->i_state);
1605 		dump_stack();
1606 		break;
1607 	}
1608 }
1609 
1610 static void
1611 isert_response_completion(struct iser_tx_desc *tx_desc,
1612 			  struct isert_cmd *isert_cmd,
1613 			  struct isert_conn *isert_conn,
1614 			  struct ib_device *ib_dev)
1615 {
1616 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1617 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1618 
1619 	if (cmd->i_state == ISTATE_SEND_TASKMGTRSP ||
1620 	    cmd->i_state == ISTATE_SEND_LOGOUTRSP ||
1621 	    cmd->i_state == ISTATE_SEND_REJECT ||
1622 	    cmd->i_state == ISTATE_SEND_TEXTRSP) {
1623 		isert_unmap_tx_desc(tx_desc, ib_dev);
1624 
1625 		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
1626 		queue_work(isert_comp_wq, &isert_cmd->comp_work);
1627 		return;
1628 	}
1629 	atomic_sub(wr->send_wr_num + 1, &isert_conn->post_send_buf_count);
1630 
1631 	cmd->i_state = ISTATE_SENT_STATUS;
1632 	isert_completion_put(tx_desc, isert_cmd, ib_dev);
1633 }
1634 
1635 static void
1636 __isert_send_completion(struct iser_tx_desc *tx_desc,
1637 		        struct isert_conn *isert_conn)
1638 {
1639 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1640 	struct isert_cmd *isert_cmd = tx_desc->isert_cmd;
1641 	struct isert_rdma_wr *wr;
1642 
1643 	if (!isert_cmd) {
1644 		atomic_dec(&isert_conn->post_send_buf_count);
1645 		isert_unmap_tx_desc(tx_desc, ib_dev);
1646 		return;
1647 	}
1648 	wr = &isert_cmd->rdma_wr;
1649 
1650 	switch (wr->iser_ib_op) {
1651 	case ISER_IB_RECV:
1652 		pr_err("isert_send_completion: Got ISER_IB_RECV\n");
1653 		dump_stack();
1654 		break;
1655 	case ISER_IB_SEND:
1656 		pr_debug("isert_send_completion: Got ISER_IB_SEND\n");
1657 		isert_response_completion(tx_desc, isert_cmd,
1658 					  isert_conn, ib_dev);
1659 		break;
1660 	case ISER_IB_RDMA_WRITE:
1661 		pr_err("isert_send_completion: Got ISER_IB_RDMA_WRITE\n");
1662 		dump_stack();
1663 		break;
1664 	case ISER_IB_RDMA_READ:
1665 		pr_debug("isert_send_completion: Got ISER_IB_RDMA_READ:\n");
1666 
1667 		atomic_sub(wr->send_wr_num, &isert_conn->post_send_buf_count);
1668 		isert_completion_rdma_read(tx_desc, isert_cmd);
1669 		break;
1670 	default:
1671 		pr_err("Unknown wr->iser_ib_op: 0x%02x\n", wr->iser_ib_op);
1672 		dump_stack();
1673 		break;
1674 	}
1675 }
1676 
1677 static void
1678 isert_send_completion(struct iser_tx_desc *tx_desc,
1679 		      struct isert_conn *isert_conn)
1680 {
1681 	struct llist_node *llnode = tx_desc->comp_llnode_batch;
1682 	struct iser_tx_desc *t;
1683 	/*
1684 	 * Drain coalesced completion llist starting from comp_llnode_batch
1685 	 * setup in isert_init_send_wr(), and then complete trailing tx_desc.
1686 	 */
1687 	while (llnode) {
1688 		t = llist_entry(llnode, struct iser_tx_desc, comp_llnode);
1689 		llnode = llist_next(llnode);
1690 		__isert_send_completion(t, isert_conn);
1691 	}
1692 	__isert_send_completion(tx_desc, isert_conn);
1693 }
1694 
1695 static void
1696 isert_cq_drain_comp_llist(struct isert_conn *isert_conn, struct ib_device *ib_dev)
1697 {
1698 	struct llist_node *llnode;
1699 	struct isert_rdma_wr *wr;
1700 	struct iser_tx_desc *t;
1701 
1702 	mutex_lock(&isert_conn->conn_mutex);
1703 	llnode = llist_del_all(&isert_conn->conn_comp_llist);
1704 	isert_conn->conn_comp_batch = 0;
1705 	mutex_unlock(&isert_conn->conn_mutex);
1706 
1707 	while (llnode) {
1708 		t = llist_entry(llnode, struct iser_tx_desc, comp_llnode);
1709 		llnode = llist_next(llnode);
1710 		wr = &t->isert_cmd->rdma_wr;
1711 
1712 		atomic_sub(wr->send_wr_num + 1, &isert_conn->post_send_buf_count);
1713 		isert_completion_put(t, t->isert_cmd, ib_dev);
1714 	}
1715 }
1716 
1717 static void
1718 isert_cq_tx_comp_err(struct iser_tx_desc *tx_desc, struct isert_conn *isert_conn)
1719 {
1720 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1721 	struct isert_cmd *isert_cmd = tx_desc->isert_cmd;
1722 	struct llist_node *llnode = tx_desc->comp_llnode_batch;
1723 	struct isert_rdma_wr *wr;
1724 	struct iser_tx_desc *t;
1725 
1726 	while (llnode) {
1727 		t = llist_entry(llnode, struct iser_tx_desc, comp_llnode);
1728 		llnode = llist_next(llnode);
1729 		wr = &t->isert_cmd->rdma_wr;
1730 
1731 		atomic_sub(wr->send_wr_num + 1, &isert_conn->post_send_buf_count);
1732 		isert_completion_put(t, t->isert_cmd, ib_dev);
1733 	}
1734 	tx_desc->comp_llnode_batch = NULL;
1735 
1736 	if (!isert_cmd)
1737 		isert_unmap_tx_desc(tx_desc, ib_dev);
1738 	else
1739 		isert_completion_put(tx_desc, isert_cmd, ib_dev);
1740 }
1741 
1742 static void
1743 isert_cq_rx_comp_err(struct isert_conn *isert_conn)
1744 {
1745 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1746 	struct iscsi_conn *conn = isert_conn->conn;
1747 
1748 	if (isert_conn->post_recv_buf_count)
1749 		return;
1750 
1751 	isert_cq_drain_comp_llist(isert_conn, ib_dev);
1752 
1753 	if (conn->sess) {
1754 		target_sess_cmd_list_set_waiting(conn->sess->se_sess);
1755 		target_wait_for_sess_cmds(conn->sess->se_sess);
1756 	}
1757 
1758 	while (atomic_read(&isert_conn->post_send_buf_count))
1759 		msleep(3000);
1760 
1761 	mutex_lock(&isert_conn->conn_mutex);
1762 	isert_conn->state = ISER_CONN_DOWN;
1763 	mutex_unlock(&isert_conn->conn_mutex);
1764 
1765 	complete(&isert_conn->conn_wait_comp_err);
1766 }
1767 
1768 static void
1769 isert_cq_tx_work(struct work_struct *work)
1770 {
1771 	struct isert_cq_desc *cq_desc = container_of(work,
1772 				struct isert_cq_desc, cq_tx_work);
1773 	struct isert_device *device = cq_desc->device;
1774 	int cq_index = cq_desc->cq_index;
1775 	struct ib_cq *tx_cq = device->dev_tx_cq[cq_index];
1776 	struct isert_conn *isert_conn;
1777 	struct iser_tx_desc *tx_desc;
1778 	struct ib_wc wc;
1779 
1780 	while (ib_poll_cq(tx_cq, 1, &wc) == 1) {
1781 		tx_desc = (struct iser_tx_desc *)(unsigned long)wc.wr_id;
1782 		isert_conn = wc.qp->qp_context;
1783 
1784 		if (wc.status == IB_WC_SUCCESS) {
1785 			isert_send_completion(tx_desc, isert_conn);
1786 		} else {
1787 			pr_debug("TX wc.status != IB_WC_SUCCESS >>>>>>>>>>>>>>\n");
1788 			pr_debug("TX wc.status: 0x%08x\n", wc.status);
1789 			pr_debug("TX wc.vendor_err: 0x%08x\n", wc.vendor_err);
1790 
1791 			if (wc.wr_id != ISER_FASTREG_LI_WRID) {
1792 				if (tx_desc->llnode_active)
1793 					continue;
1794 
1795 				atomic_dec(&isert_conn->post_send_buf_count);
1796 				isert_cq_tx_comp_err(tx_desc, isert_conn);
1797 			}
1798 		}
1799 	}
1800 
1801 	ib_req_notify_cq(tx_cq, IB_CQ_NEXT_COMP);
1802 }
1803 
1804 static void
1805 isert_cq_tx_callback(struct ib_cq *cq, void *context)
1806 {
1807 	struct isert_cq_desc *cq_desc = (struct isert_cq_desc *)context;
1808 
1809 	queue_work(isert_comp_wq, &cq_desc->cq_tx_work);
1810 }
1811 
1812 static void
1813 isert_cq_rx_work(struct work_struct *work)
1814 {
1815 	struct isert_cq_desc *cq_desc = container_of(work,
1816 			struct isert_cq_desc, cq_rx_work);
1817 	struct isert_device *device = cq_desc->device;
1818 	int cq_index = cq_desc->cq_index;
1819 	struct ib_cq *rx_cq = device->dev_rx_cq[cq_index];
1820 	struct isert_conn *isert_conn;
1821 	struct iser_rx_desc *rx_desc;
1822 	struct ib_wc wc;
1823 	unsigned long xfer_len;
1824 
1825 	while (ib_poll_cq(rx_cq, 1, &wc) == 1) {
1826 		rx_desc = (struct iser_rx_desc *)(unsigned long)wc.wr_id;
1827 		isert_conn = wc.qp->qp_context;
1828 
1829 		if (wc.status == IB_WC_SUCCESS) {
1830 			xfer_len = (unsigned long)wc.byte_len;
1831 			isert_rx_completion(rx_desc, isert_conn, xfer_len);
1832 		} else {
1833 			pr_debug("RX wc.status != IB_WC_SUCCESS >>>>>>>>>>>>>>\n");
1834 			if (wc.status != IB_WC_WR_FLUSH_ERR) {
1835 				pr_debug("RX wc.status: 0x%08x\n", wc.status);
1836 				pr_debug("RX wc.vendor_err: 0x%08x\n",
1837 					 wc.vendor_err);
1838 			}
1839 			isert_conn->post_recv_buf_count--;
1840 			isert_cq_rx_comp_err(isert_conn);
1841 		}
1842 	}
1843 
1844 	ib_req_notify_cq(rx_cq, IB_CQ_NEXT_COMP);
1845 }
1846 
1847 static void
1848 isert_cq_rx_callback(struct ib_cq *cq, void *context)
1849 {
1850 	struct isert_cq_desc *cq_desc = (struct isert_cq_desc *)context;
1851 
1852 	queue_work(isert_rx_wq, &cq_desc->cq_rx_work);
1853 }
1854 
1855 static int
1856 isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
1857 {
1858 	struct ib_send_wr *wr_failed;
1859 	int ret;
1860 
1861 	atomic_inc(&isert_conn->post_send_buf_count);
1862 
1863 	ret = ib_post_send(isert_conn->conn_qp, &isert_cmd->tx_desc.send_wr,
1864 			   &wr_failed);
1865 	if (ret) {
1866 		pr_err("ib_post_send failed with %d\n", ret);
1867 		atomic_dec(&isert_conn->post_send_buf_count);
1868 		return ret;
1869 	}
1870 	return ret;
1871 }
1872 
1873 static int
1874 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
1875 {
1876 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1877 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1878 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1879 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
1880 				&isert_cmd->tx_desc.iscsi_header;
1881 
1882 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1883 	iscsit_build_rsp_pdu(cmd, conn, true, hdr);
1884 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1885 	/*
1886 	 * Attach SENSE DATA payload to iSCSI Response PDU
1887 	 */
1888 	if (cmd->se_cmd.sense_buffer &&
1889 	    ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1890 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
1891 		struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1892 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1893 		u32 padding, pdu_len;
1894 
1895 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length,
1896 				   cmd->sense_buffer);
1897 		cmd->se_cmd.scsi_sense_length += sizeof(__be16);
1898 
1899 		padding = -(cmd->se_cmd.scsi_sense_length) & 3;
1900 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
1901 		pdu_len = cmd->se_cmd.scsi_sense_length + padding;
1902 
1903 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1904 				(void *)cmd->sense_buffer, pdu_len,
1905 				DMA_TO_DEVICE);
1906 
1907 		isert_cmd->pdu_buf_len = pdu_len;
1908 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1909 		tx_dsg->length	= pdu_len;
1910 		tx_dsg->lkey	= isert_conn->conn_mr->lkey;
1911 		isert_cmd->tx_desc.num_sge = 2;
1912 	}
1913 
1914 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, true);
1915 
1916 	pr_debug("Posting SCSI Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1917 
1918 	return isert_post_response(isert_conn, isert_cmd);
1919 }
1920 
1921 static int
1922 isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
1923 		bool nopout_response)
1924 {
1925 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1926 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1927 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1928 
1929 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1930 	iscsit_build_nopin_rsp(cmd, conn, (struct iscsi_nopin *)
1931 			       &isert_cmd->tx_desc.iscsi_header,
1932 			       nopout_response);
1933 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1934 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1935 
1936 	pr_debug("Posting NOPIN Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1937 
1938 	return isert_post_response(isert_conn, isert_cmd);
1939 }
1940 
1941 static int
1942 isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1943 {
1944 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1945 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1946 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1947 
1948 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1949 	iscsit_build_logout_rsp(cmd, conn, (struct iscsi_logout_rsp *)
1950 				&isert_cmd->tx_desc.iscsi_header);
1951 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1952 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1953 
1954 	pr_debug("Posting Logout Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1955 
1956 	return isert_post_response(isert_conn, isert_cmd);
1957 }
1958 
1959 static int
1960 isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1961 {
1962 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1963 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1964 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1965 
1966 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1967 	iscsit_build_task_mgt_rsp(cmd, conn, (struct iscsi_tm_rsp *)
1968 				  &isert_cmd->tx_desc.iscsi_header);
1969 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1970 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1971 
1972 	pr_debug("Posting Task Management Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1973 
1974 	return isert_post_response(isert_conn, isert_cmd);
1975 }
1976 
1977 static int
1978 isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1979 {
1980 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1981 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1982 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1983 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1984 	struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1985 	struct iscsi_reject *hdr =
1986 		(struct iscsi_reject *)&isert_cmd->tx_desc.iscsi_header;
1987 
1988 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1989 	iscsit_build_reject(cmd, conn, hdr);
1990 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1991 
1992 	hton24(hdr->dlength, ISCSI_HDR_LEN);
1993 	isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1994 			(void *)cmd->buf_ptr, ISCSI_HDR_LEN,
1995 			DMA_TO_DEVICE);
1996 	isert_cmd->pdu_buf_len = ISCSI_HDR_LEN;
1997 	tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1998 	tx_dsg->length	= ISCSI_HDR_LEN;
1999 	tx_dsg->lkey	= isert_conn->conn_mr->lkey;
2000 	isert_cmd->tx_desc.num_sge = 2;
2001 
2002 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
2003 
2004 	pr_debug("Posting Reject IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
2005 
2006 	return isert_post_response(isert_conn, isert_cmd);
2007 }
2008 
2009 static int
2010 isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2011 {
2012 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2013 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2014 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
2015 	struct iscsi_text_rsp *hdr =
2016 		(struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
2017 	u32 txt_rsp_len;
2018 	int rc;
2019 
2020 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2021 	rc = iscsit_build_text_rsp(cmd, conn, hdr);
2022 	if (rc < 0)
2023 		return rc;
2024 
2025 	txt_rsp_len = rc;
2026 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2027 
2028 	if (txt_rsp_len) {
2029 		struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2030 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
2031 		void *txt_rsp_buf = cmd->buf_ptr;
2032 
2033 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
2034 				txt_rsp_buf, txt_rsp_len, DMA_TO_DEVICE);
2035 
2036 		isert_cmd->pdu_buf_len = txt_rsp_len;
2037 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
2038 		tx_dsg->length	= txt_rsp_len;
2039 		tx_dsg->lkey	= isert_conn->conn_mr->lkey;
2040 		isert_cmd->tx_desc.num_sge = 2;
2041 	}
2042 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
2043 
2044 	pr_debug("Posting Text Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
2045 
2046 	return isert_post_response(isert_conn, isert_cmd);
2047 }
2048 
2049 static int
2050 isert_build_rdma_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
2051 		    struct ib_sge *ib_sge, struct ib_send_wr *send_wr,
2052 		    u32 data_left, u32 offset)
2053 {
2054 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
2055 	struct scatterlist *sg_start, *tmp_sg;
2056 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2057 	u32 sg_off, page_off;
2058 	int i = 0, sg_nents;
2059 
2060 	sg_off = offset / PAGE_SIZE;
2061 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
2062 	sg_nents = min(cmd->se_cmd.t_data_nents - sg_off, isert_conn->max_sge);
2063 	page_off = offset % PAGE_SIZE;
2064 
2065 	send_wr->sg_list = ib_sge;
2066 	send_wr->num_sge = sg_nents;
2067 	send_wr->wr_id = (unsigned long)&isert_cmd->tx_desc;
2068 	/*
2069 	 * Perform mapping of TCM scatterlist memory ib_sge dma_addr.
2070 	 */
2071 	for_each_sg(sg_start, tmp_sg, sg_nents, i) {
2072 		pr_debug("ISER RDMA from SGL dma_addr: 0x%16llx dma_len: %u, page_off: %u\n",
2073 			 (unsigned long long)tmp_sg->dma_address,
2074 			 tmp_sg->length, page_off);
2075 
2076 		ib_sge->addr = ib_sg_dma_address(ib_dev, tmp_sg) + page_off;
2077 		ib_sge->length = min_t(u32, data_left,
2078 				ib_sg_dma_len(ib_dev, tmp_sg) - page_off);
2079 		ib_sge->lkey = isert_conn->conn_mr->lkey;
2080 
2081 		pr_debug("RDMA ib_sge: addr: 0x%16llx  length: %u lkey: %08x\n",
2082 			 ib_sge->addr, ib_sge->length, ib_sge->lkey);
2083 		page_off = 0;
2084 		data_left -= ib_sge->length;
2085 		ib_sge++;
2086 		pr_debug("Incrementing ib_sge pointer to %p\n", ib_sge);
2087 	}
2088 
2089 	pr_debug("Set outgoing sg_list: %p num_sg: %u from TCM SGLs\n",
2090 		 send_wr->sg_list, send_wr->num_sge);
2091 
2092 	return sg_nents;
2093 }
2094 
2095 static int
2096 isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2097 	       struct isert_rdma_wr *wr)
2098 {
2099 	struct se_cmd *se_cmd = &cmd->se_cmd;
2100 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2101 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2102 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2103 	struct ib_send_wr *send_wr;
2104 	struct ib_sge *ib_sge;
2105 	struct scatterlist *sg_start;
2106 	u32 sg_off = 0, sg_nents;
2107 	u32 offset = 0, data_len, data_left, rdma_write_max, va_offset = 0;
2108 	int ret = 0, count, i, ib_sge_cnt;
2109 
2110 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2111 		data_left = se_cmd->data_length;
2112 	} else {
2113 		sg_off = cmd->write_data_done / PAGE_SIZE;
2114 		data_left = se_cmd->data_length - cmd->write_data_done;
2115 		offset = cmd->write_data_done;
2116 		isert_cmd->tx_desc.isert_cmd = isert_cmd;
2117 	}
2118 
2119 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
2120 	sg_nents = se_cmd->t_data_nents - sg_off;
2121 
2122 	count = ib_dma_map_sg(ib_dev, sg_start, sg_nents,
2123 			      (wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2124 			      DMA_TO_DEVICE : DMA_FROM_DEVICE);
2125 	if (unlikely(!count)) {
2126 		pr_err("Cmd: %p unrable to map SGs\n", isert_cmd);
2127 		return -EINVAL;
2128 	}
2129 	wr->sge = sg_start;
2130 	wr->num_sge = sg_nents;
2131 	wr->cur_rdma_length = data_left;
2132 	pr_debug("Mapped cmd: %p count: %u sg: %p sg_nents: %u rdma_len %d\n",
2133 		 isert_cmd, count, sg_start, sg_nents, data_left);
2134 
2135 	ib_sge = kzalloc(sizeof(struct ib_sge) * sg_nents, GFP_KERNEL);
2136 	if (!ib_sge) {
2137 		pr_warn("Unable to allocate ib_sge\n");
2138 		ret = -ENOMEM;
2139 		goto unmap_sg;
2140 	}
2141 	wr->ib_sge = ib_sge;
2142 
2143 	wr->send_wr_num = DIV_ROUND_UP(sg_nents, isert_conn->max_sge);
2144 	wr->send_wr = kzalloc(sizeof(struct ib_send_wr) * wr->send_wr_num,
2145 				GFP_KERNEL);
2146 	if (!wr->send_wr) {
2147 		pr_debug("Unable to allocate wr->send_wr\n");
2148 		ret = -ENOMEM;
2149 		goto unmap_sg;
2150 	}
2151 
2152 	wr->isert_cmd = isert_cmd;
2153 	rdma_write_max = isert_conn->max_sge * PAGE_SIZE;
2154 
2155 	for (i = 0; i < wr->send_wr_num; i++) {
2156 		send_wr = &isert_cmd->rdma_wr.send_wr[i];
2157 		data_len = min(data_left, rdma_write_max);
2158 
2159 		send_wr->send_flags = 0;
2160 		if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2161 			send_wr->opcode = IB_WR_RDMA_WRITE;
2162 			send_wr->wr.rdma.remote_addr = isert_cmd->read_va + offset;
2163 			send_wr->wr.rdma.rkey = isert_cmd->read_stag;
2164 			if (i + 1 == wr->send_wr_num)
2165 				send_wr->next = &isert_cmd->tx_desc.send_wr;
2166 			else
2167 				send_wr->next = &wr->send_wr[i + 1];
2168 		} else {
2169 			send_wr->opcode = IB_WR_RDMA_READ;
2170 			send_wr->wr.rdma.remote_addr = isert_cmd->write_va + va_offset;
2171 			send_wr->wr.rdma.rkey = isert_cmd->write_stag;
2172 			if (i + 1 == wr->send_wr_num)
2173 				send_wr->send_flags = IB_SEND_SIGNALED;
2174 			else
2175 				send_wr->next = &wr->send_wr[i + 1];
2176 		}
2177 
2178 		ib_sge_cnt = isert_build_rdma_wr(isert_conn, isert_cmd, ib_sge,
2179 					send_wr, data_len, offset);
2180 		ib_sge += ib_sge_cnt;
2181 
2182 		offset += data_len;
2183 		va_offset += data_len;
2184 		data_left -= data_len;
2185 	}
2186 
2187 	return 0;
2188 unmap_sg:
2189 	ib_dma_unmap_sg(ib_dev, sg_start, sg_nents,
2190 			(wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2191 			DMA_TO_DEVICE : DMA_FROM_DEVICE);
2192 	return ret;
2193 }
2194 
2195 static int
2196 isert_map_fr_pagelist(struct ib_device *ib_dev,
2197 		      struct scatterlist *sg_start, int sg_nents, u64 *fr_pl)
2198 {
2199 	u64 start_addr, end_addr, page, chunk_start = 0;
2200 	struct scatterlist *tmp_sg;
2201 	int i = 0, new_chunk, last_ent, n_pages;
2202 
2203 	n_pages = 0;
2204 	new_chunk = 1;
2205 	last_ent = sg_nents - 1;
2206 	for_each_sg(sg_start, tmp_sg, sg_nents, i) {
2207 		start_addr = ib_sg_dma_address(ib_dev, tmp_sg);
2208 		if (new_chunk)
2209 			chunk_start = start_addr;
2210 		end_addr = start_addr + ib_sg_dma_len(ib_dev, tmp_sg);
2211 
2212 		pr_debug("SGL[%d] dma_addr: 0x%16llx len: %u\n",
2213 			 i, (unsigned long long)tmp_sg->dma_address,
2214 			 tmp_sg->length);
2215 
2216 		if ((end_addr & ~PAGE_MASK) && i < last_ent) {
2217 			new_chunk = 0;
2218 			continue;
2219 		}
2220 		new_chunk = 1;
2221 
2222 		page = chunk_start & PAGE_MASK;
2223 		do {
2224 			fr_pl[n_pages++] = page;
2225 			pr_debug("Mapped page_list[%d] page_addr: 0x%16llx\n",
2226 				 n_pages - 1, page);
2227 			page += PAGE_SIZE;
2228 		} while (page < end_addr);
2229 	}
2230 
2231 	return n_pages;
2232 }
2233 
2234 static int
2235 isert_fast_reg_mr(struct fast_reg_descriptor *fr_desc,
2236 		  struct isert_conn *isert_conn, struct scatterlist *sg_start,
2237 		  struct ib_sge *ib_sge, u32 sg_nents, u32 offset,
2238 		  unsigned int data_len)
2239 {
2240 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2241 	struct ib_send_wr fr_wr, inv_wr;
2242 	struct ib_send_wr *bad_wr, *wr = NULL;
2243 	int ret, pagelist_len;
2244 	u32 page_off;
2245 	u8 key;
2246 
2247 	sg_nents = min_t(unsigned int, sg_nents, ISCSI_ISER_SG_TABLESIZE);
2248 	page_off = offset % PAGE_SIZE;
2249 
2250 	pr_debug("Use fr_desc %p sg_nents %d offset %u\n",
2251 		 fr_desc, sg_nents, offset);
2252 
2253 	pagelist_len = isert_map_fr_pagelist(ib_dev, sg_start, sg_nents,
2254 					     &fr_desc->data_frpl->page_list[0]);
2255 
2256 	if (!fr_desc->valid) {
2257 		memset(&inv_wr, 0, sizeof(inv_wr));
2258 		inv_wr.wr_id = ISER_FASTREG_LI_WRID;
2259 		inv_wr.opcode = IB_WR_LOCAL_INV;
2260 		inv_wr.ex.invalidate_rkey = fr_desc->data_mr->rkey;
2261 		wr = &inv_wr;
2262 		/* Bump the key */
2263 		key = (u8)(fr_desc->data_mr->rkey & 0x000000FF);
2264 		ib_update_fast_reg_key(fr_desc->data_mr, ++key);
2265 	}
2266 
2267 	/* Prepare FASTREG WR */
2268 	memset(&fr_wr, 0, sizeof(fr_wr));
2269 	fr_wr.wr_id = ISER_FASTREG_LI_WRID;
2270 	fr_wr.opcode = IB_WR_FAST_REG_MR;
2271 	fr_wr.wr.fast_reg.iova_start =
2272 		fr_desc->data_frpl->page_list[0] + page_off;
2273 	fr_wr.wr.fast_reg.page_list = fr_desc->data_frpl;
2274 	fr_wr.wr.fast_reg.page_list_len = pagelist_len;
2275 	fr_wr.wr.fast_reg.page_shift = PAGE_SHIFT;
2276 	fr_wr.wr.fast_reg.length = data_len;
2277 	fr_wr.wr.fast_reg.rkey = fr_desc->data_mr->rkey;
2278 	fr_wr.wr.fast_reg.access_flags = IB_ACCESS_LOCAL_WRITE;
2279 
2280 	if (!wr)
2281 		wr = &fr_wr;
2282 	else
2283 		wr->next = &fr_wr;
2284 
2285 	ret = ib_post_send(isert_conn->conn_qp, wr, &bad_wr);
2286 	if (ret) {
2287 		pr_err("fast registration failed, ret:%d\n", ret);
2288 		return ret;
2289 	}
2290 	fr_desc->valid = false;
2291 
2292 	ib_sge->lkey = fr_desc->data_mr->lkey;
2293 	ib_sge->addr = fr_desc->data_frpl->page_list[0] + page_off;
2294 	ib_sge->length = data_len;
2295 
2296 	pr_debug("RDMA ib_sge: addr: 0x%16llx  length: %u lkey: %08x\n",
2297 		 ib_sge->addr, ib_sge->length, ib_sge->lkey);
2298 
2299 	return ret;
2300 }
2301 
2302 static int
2303 isert_reg_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2304 	       struct isert_rdma_wr *wr)
2305 {
2306 	struct se_cmd *se_cmd = &cmd->se_cmd;
2307 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2308 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2309 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2310 	struct ib_send_wr *send_wr;
2311 	struct ib_sge *ib_sge;
2312 	struct scatterlist *sg_start;
2313 	struct fast_reg_descriptor *fr_desc;
2314 	u32 sg_off = 0, sg_nents;
2315 	u32 offset = 0, data_len, data_left, rdma_write_max;
2316 	int ret = 0, count;
2317 	unsigned long flags;
2318 
2319 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2320 		data_left = se_cmd->data_length;
2321 	} else {
2322 		offset = cmd->write_data_done;
2323 		sg_off = offset / PAGE_SIZE;
2324 		data_left = se_cmd->data_length - cmd->write_data_done;
2325 		isert_cmd->tx_desc.isert_cmd = isert_cmd;
2326 	}
2327 
2328 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
2329 	sg_nents = se_cmd->t_data_nents - sg_off;
2330 
2331 	count = ib_dma_map_sg(ib_dev, sg_start, sg_nents,
2332 			      (wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2333 			      DMA_TO_DEVICE : DMA_FROM_DEVICE);
2334 	if (unlikely(!count)) {
2335 		pr_err("Cmd: %p unrable to map SGs\n", isert_cmd);
2336 		return -EINVAL;
2337 	}
2338 	wr->sge = sg_start;
2339 	wr->num_sge = sg_nents;
2340 	pr_debug("Mapped cmd: %p count: %u sg: %p sg_nents: %u rdma_len %d\n",
2341 		 isert_cmd, count, sg_start, sg_nents, data_left);
2342 
2343 	memset(&wr->s_ib_sge, 0, sizeof(*ib_sge));
2344 	ib_sge = &wr->s_ib_sge;
2345 	wr->ib_sge = ib_sge;
2346 
2347 	wr->send_wr_num = 1;
2348 	memset(&wr->s_send_wr, 0, sizeof(*send_wr));
2349 	wr->send_wr = &wr->s_send_wr;
2350 
2351 	wr->isert_cmd = isert_cmd;
2352 	rdma_write_max = ISCSI_ISER_SG_TABLESIZE * PAGE_SIZE;
2353 
2354 	send_wr = &isert_cmd->rdma_wr.s_send_wr;
2355 	send_wr->sg_list = ib_sge;
2356 	send_wr->num_sge = 1;
2357 	send_wr->wr_id = (unsigned long)&isert_cmd->tx_desc;
2358 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2359 		send_wr->opcode = IB_WR_RDMA_WRITE;
2360 		send_wr->wr.rdma.remote_addr = isert_cmd->read_va;
2361 		send_wr->wr.rdma.rkey = isert_cmd->read_stag;
2362 		send_wr->send_flags = 0;
2363 		send_wr->next = &isert_cmd->tx_desc.send_wr;
2364 	} else {
2365 		send_wr->opcode = IB_WR_RDMA_READ;
2366 		send_wr->wr.rdma.remote_addr = isert_cmd->write_va;
2367 		send_wr->wr.rdma.rkey = isert_cmd->write_stag;
2368 		send_wr->send_flags = IB_SEND_SIGNALED;
2369 	}
2370 
2371 	data_len = min(data_left, rdma_write_max);
2372 	wr->cur_rdma_length = data_len;
2373 
2374 	/* if there is a single dma entry, dma mr is sufficient */
2375 	if (count == 1) {
2376 		ib_sge->addr = ib_sg_dma_address(ib_dev, &sg_start[0]);
2377 		ib_sge->length = ib_sg_dma_len(ib_dev, &sg_start[0]);
2378 		ib_sge->lkey = isert_conn->conn_mr->lkey;
2379 		wr->fr_desc = NULL;
2380 	} else {
2381 		spin_lock_irqsave(&isert_conn->conn_lock, flags);
2382 		fr_desc = list_first_entry(&isert_conn->conn_fr_pool,
2383 					   struct fast_reg_descriptor, list);
2384 		list_del(&fr_desc->list);
2385 		spin_unlock_irqrestore(&isert_conn->conn_lock, flags);
2386 		wr->fr_desc = fr_desc;
2387 
2388 		ret = isert_fast_reg_mr(fr_desc, isert_conn, sg_start,
2389 					ib_sge, sg_nents, offset, data_len);
2390 		if (ret) {
2391 			list_add_tail(&fr_desc->list, &isert_conn->conn_fr_pool);
2392 			goto unmap_sg;
2393 		}
2394 	}
2395 
2396 	return 0;
2397 
2398 unmap_sg:
2399 	ib_dma_unmap_sg(ib_dev, sg_start, sg_nents,
2400 			(wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2401 			DMA_TO_DEVICE : DMA_FROM_DEVICE);
2402 	return ret;
2403 }
2404 
2405 static int
2406 isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
2407 {
2408 	struct se_cmd *se_cmd = &cmd->se_cmd;
2409 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2410 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
2411 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2412 	struct isert_device *device = isert_conn->conn_device;
2413 	struct ib_send_wr *wr_failed;
2414 	int rc;
2415 
2416 	pr_debug("Cmd: %p RDMA_WRITE data_length: %u\n",
2417 		 isert_cmd, se_cmd->data_length);
2418 	wr->iser_ib_op = ISER_IB_RDMA_WRITE;
2419 	rc = device->reg_rdma_mem(conn, cmd, wr);
2420 	if (rc) {
2421 		pr_err("Cmd: %p failed to prepare RDMA res\n", isert_cmd);
2422 		return rc;
2423 	}
2424 
2425 	/*
2426 	 * Build isert_conn->tx_desc for iSCSI response PDU and attach
2427 	 */
2428 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2429 	iscsit_build_rsp_pdu(cmd, conn, true, (struct iscsi_scsi_rsp *)
2430 			     &isert_cmd->tx_desc.iscsi_header);
2431 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2432 	isert_init_send_wr(isert_conn, isert_cmd,
2433 			   &isert_cmd->tx_desc.send_wr, true);
2434 
2435 	atomic_add(wr->send_wr_num + 1, &isert_conn->post_send_buf_count);
2436 
2437 	rc = ib_post_send(isert_conn->conn_qp, wr->send_wr, &wr_failed);
2438 	if (rc) {
2439 		pr_warn("ib_post_send() failed for IB_WR_RDMA_WRITE\n");
2440 		atomic_sub(wr->send_wr_num + 1, &isert_conn->post_send_buf_count);
2441 	}
2442 	pr_debug("Cmd: %p posted RDMA_WRITE + Response for iSER Data READ\n",
2443 		 isert_cmd);
2444 
2445 	return 1;
2446 }
2447 
2448 static int
2449 isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
2450 {
2451 	struct se_cmd *se_cmd = &cmd->se_cmd;
2452 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2453 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
2454 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2455 	struct isert_device *device = isert_conn->conn_device;
2456 	struct ib_send_wr *wr_failed;
2457 	int rc;
2458 
2459 	pr_debug("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
2460 		 isert_cmd, se_cmd->data_length, cmd->write_data_done);
2461 	wr->iser_ib_op = ISER_IB_RDMA_READ;
2462 	rc = device->reg_rdma_mem(conn, cmd, wr);
2463 	if (rc) {
2464 		pr_err("Cmd: %p failed to prepare RDMA res\n", isert_cmd);
2465 		return rc;
2466 	}
2467 
2468 	atomic_add(wr->send_wr_num, &isert_conn->post_send_buf_count);
2469 
2470 	rc = ib_post_send(isert_conn->conn_qp, wr->send_wr, &wr_failed);
2471 	if (rc) {
2472 		pr_warn("ib_post_send() failed for IB_WR_RDMA_READ\n");
2473 		atomic_sub(wr->send_wr_num, &isert_conn->post_send_buf_count);
2474 	}
2475 	pr_debug("Cmd: %p posted RDMA_READ memory for ISER Data WRITE\n",
2476 		 isert_cmd);
2477 
2478 	return 0;
2479 }
2480 
2481 static int
2482 isert_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2483 {
2484 	int ret;
2485 
2486 	switch (state) {
2487 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
2488 		ret = isert_put_nopin(cmd, conn, false);
2489 		break;
2490 	default:
2491 		pr_err("Unknown immediate state: 0x%02x\n", state);
2492 		ret = -EINVAL;
2493 		break;
2494 	}
2495 
2496 	return ret;
2497 }
2498 
2499 static int
2500 isert_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2501 {
2502 	int ret;
2503 
2504 	switch (state) {
2505 	case ISTATE_SEND_LOGOUTRSP:
2506 		ret = isert_put_logout_rsp(cmd, conn);
2507 		if (!ret) {
2508 			pr_debug("Returning iSER Logout -EAGAIN\n");
2509 			ret = -EAGAIN;
2510 		}
2511 		break;
2512 	case ISTATE_SEND_NOPIN:
2513 		ret = isert_put_nopin(cmd, conn, true);
2514 		break;
2515 	case ISTATE_SEND_TASKMGTRSP:
2516 		ret = isert_put_tm_rsp(cmd, conn);
2517 		break;
2518 	case ISTATE_SEND_REJECT:
2519 		ret = isert_put_reject(cmd, conn);
2520 		break;
2521 	case ISTATE_SEND_TEXTRSP:
2522 		ret = isert_put_text_rsp(cmd, conn);
2523 		break;
2524 	case ISTATE_SEND_STATUS:
2525 		/*
2526 		 * Special case for sending non GOOD SCSI status from TX thread
2527 		 * context during pre se_cmd excecution failure.
2528 		 */
2529 		ret = isert_put_response(conn, cmd);
2530 		break;
2531 	default:
2532 		pr_err("Unknown response state: 0x%02x\n", state);
2533 		ret = -EINVAL;
2534 		break;
2535 	}
2536 
2537 	return ret;
2538 }
2539 
2540 static int
2541 isert_setup_np(struct iscsi_np *np,
2542 	       struct __kernel_sockaddr_storage *ksockaddr)
2543 {
2544 	struct isert_np *isert_np;
2545 	struct rdma_cm_id *isert_lid;
2546 	struct sockaddr *sa;
2547 	int ret;
2548 
2549 	isert_np = kzalloc(sizeof(struct isert_np), GFP_KERNEL);
2550 	if (!isert_np) {
2551 		pr_err("Unable to allocate struct isert_np\n");
2552 		return -ENOMEM;
2553 	}
2554 	init_waitqueue_head(&isert_np->np_accept_wq);
2555 	mutex_init(&isert_np->np_accept_mutex);
2556 	INIT_LIST_HEAD(&isert_np->np_accept_list);
2557 	init_completion(&isert_np->np_login_comp);
2558 
2559 	sa = (struct sockaddr *)ksockaddr;
2560 	pr_debug("ksockaddr: %p, sa: %p\n", ksockaddr, sa);
2561 	/*
2562 	 * Setup the np->np_sockaddr from the passed sockaddr setup
2563 	 * in iscsi_target_configfs.c code..
2564 	 */
2565 	memcpy(&np->np_sockaddr, ksockaddr,
2566 	       sizeof(struct __kernel_sockaddr_storage));
2567 
2568 	isert_lid = rdma_create_id(isert_cma_handler, np, RDMA_PS_TCP,
2569 				IB_QPT_RC);
2570 	if (IS_ERR(isert_lid)) {
2571 		pr_err("rdma_create_id() for isert_listen_handler failed: %ld\n",
2572 		       PTR_ERR(isert_lid));
2573 		ret = PTR_ERR(isert_lid);
2574 		goto out;
2575 	}
2576 
2577 	ret = rdma_bind_addr(isert_lid, sa);
2578 	if (ret) {
2579 		pr_err("rdma_bind_addr() for isert_lid failed: %d\n", ret);
2580 		goto out_lid;
2581 	}
2582 
2583 	ret = rdma_listen(isert_lid, ISERT_RDMA_LISTEN_BACKLOG);
2584 	if (ret) {
2585 		pr_err("rdma_listen() for isert_lid failed: %d\n", ret);
2586 		goto out_lid;
2587 	}
2588 
2589 	isert_np->np_cm_id = isert_lid;
2590 	np->np_context = isert_np;
2591 	pr_debug("Setup isert_lid->context: %p\n", isert_lid->context);
2592 
2593 	return 0;
2594 
2595 out_lid:
2596 	rdma_destroy_id(isert_lid);
2597 out:
2598 	kfree(isert_np);
2599 	return ret;
2600 }
2601 
2602 static int
2603 isert_check_accept_queue(struct isert_np *isert_np)
2604 {
2605 	int empty;
2606 
2607 	mutex_lock(&isert_np->np_accept_mutex);
2608 	empty = list_empty(&isert_np->np_accept_list);
2609 	mutex_unlock(&isert_np->np_accept_mutex);
2610 
2611 	return empty;
2612 }
2613 
2614 static int
2615 isert_rdma_accept(struct isert_conn *isert_conn)
2616 {
2617 	struct rdma_cm_id *cm_id = isert_conn->conn_cm_id;
2618 	struct rdma_conn_param cp;
2619 	int ret;
2620 
2621 	memset(&cp, 0, sizeof(struct rdma_conn_param));
2622 	cp.responder_resources = isert_conn->responder_resources;
2623 	cp.initiator_depth = isert_conn->initiator_depth;
2624 	cp.retry_count = 7;
2625 	cp.rnr_retry_count = 7;
2626 
2627 	pr_debug("Before rdma_accept >>>>>>>>>>>>>>>>>>>>.\n");
2628 
2629 	ret = rdma_accept(cm_id, &cp);
2630 	if (ret) {
2631 		pr_err("rdma_accept() failed with: %d\n", ret);
2632 		return ret;
2633 	}
2634 
2635 	pr_debug("After rdma_accept >>>>>>>>>>>>>>>>>>>>>.\n");
2636 
2637 	return 0;
2638 }
2639 
2640 static int
2641 isert_get_login_rx(struct iscsi_conn *conn, struct iscsi_login *login)
2642 {
2643 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2644 	int ret;
2645 
2646 	pr_debug("isert_get_login_rx before conn_login_comp conn: %p\n", conn);
2647 	/*
2648 	 * For login requests after the first PDU, isert_rx_login_req() will
2649 	 * kick schedule_delayed_work(&conn->login_work) as the packet is
2650 	 * received, which turns this callback from iscsi_target_do_login_rx()
2651 	 * into a NOP.
2652 	 */
2653 	if (!login->first_request)
2654 		return 0;
2655 
2656 	ret = wait_for_completion_interruptible(&isert_conn->conn_login_comp);
2657 	if (ret)
2658 		return ret;
2659 
2660 	pr_debug("isert_get_login_rx processing login->req: %p\n", login->req);
2661 	return 0;
2662 }
2663 
2664 static void
2665 isert_set_conn_info(struct iscsi_np *np, struct iscsi_conn *conn,
2666 		    struct isert_conn *isert_conn)
2667 {
2668 	struct rdma_cm_id *cm_id = isert_conn->conn_cm_id;
2669 	struct rdma_route *cm_route = &cm_id->route;
2670 	struct sockaddr_in *sock_in;
2671 	struct sockaddr_in6 *sock_in6;
2672 
2673 	conn->login_family = np->np_sockaddr.ss_family;
2674 
2675 	if (np->np_sockaddr.ss_family == AF_INET6) {
2676 		sock_in6 = (struct sockaddr_in6 *)&cm_route->addr.dst_addr;
2677 		snprintf(conn->login_ip, sizeof(conn->login_ip), "%pI6c",
2678 			 &sock_in6->sin6_addr.in6_u);
2679 		conn->login_port = ntohs(sock_in6->sin6_port);
2680 
2681 		sock_in6 = (struct sockaddr_in6 *)&cm_route->addr.src_addr;
2682 		snprintf(conn->local_ip, sizeof(conn->local_ip), "%pI6c",
2683 			 &sock_in6->sin6_addr.in6_u);
2684 		conn->local_port = ntohs(sock_in6->sin6_port);
2685 	} else {
2686 		sock_in = (struct sockaddr_in *)&cm_route->addr.dst_addr;
2687 		sprintf(conn->login_ip, "%pI4",
2688 			&sock_in->sin_addr.s_addr);
2689 		conn->login_port = ntohs(sock_in->sin_port);
2690 
2691 		sock_in = (struct sockaddr_in *)&cm_route->addr.src_addr;
2692 		sprintf(conn->local_ip, "%pI4",
2693 			&sock_in->sin_addr.s_addr);
2694 		conn->local_port = ntohs(sock_in->sin_port);
2695 	}
2696 }
2697 
2698 static int
2699 isert_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
2700 {
2701 	struct isert_np *isert_np = (struct isert_np *)np->np_context;
2702 	struct isert_conn *isert_conn;
2703 	int max_accept = 0, ret;
2704 
2705 accept_wait:
2706 	ret = wait_event_interruptible(isert_np->np_accept_wq,
2707 			!isert_check_accept_queue(isert_np) ||
2708 			np->np_thread_state == ISCSI_NP_THREAD_RESET);
2709 	if (max_accept > 5)
2710 		return -ENODEV;
2711 
2712 	spin_lock_bh(&np->np_thread_lock);
2713 	if (np->np_thread_state == ISCSI_NP_THREAD_RESET) {
2714 		spin_unlock_bh(&np->np_thread_lock);
2715 		pr_err("ISCSI_NP_THREAD_RESET for isert_accept_np\n");
2716 		return -ENODEV;
2717 	}
2718 	spin_unlock_bh(&np->np_thread_lock);
2719 
2720 	mutex_lock(&isert_np->np_accept_mutex);
2721 	if (list_empty(&isert_np->np_accept_list)) {
2722 		mutex_unlock(&isert_np->np_accept_mutex);
2723 		max_accept++;
2724 		goto accept_wait;
2725 	}
2726 	isert_conn = list_first_entry(&isert_np->np_accept_list,
2727 			struct isert_conn, conn_accept_node);
2728 	list_del_init(&isert_conn->conn_accept_node);
2729 	mutex_unlock(&isert_np->np_accept_mutex);
2730 
2731 	conn->context = isert_conn;
2732 	isert_conn->conn = conn;
2733 	max_accept = 0;
2734 
2735 	ret = isert_rdma_post_recvl(isert_conn);
2736 	if (ret)
2737 		return ret;
2738 
2739 	ret = isert_rdma_accept(isert_conn);
2740 	if (ret)
2741 		return ret;
2742 
2743 	isert_set_conn_info(np, conn, isert_conn);
2744 
2745 	pr_debug("Processing isert_accept_np: isert_conn: %p\n", isert_conn);
2746 	return 0;
2747 }
2748 
2749 static void
2750 isert_free_np(struct iscsi_np *np)
2751 {
2752 	struct isert_np *isert_np = (struct isert_np *)np->np_context;
2753 
2754 	rdma_destroy_id(isert_np->np_cm_id);
2755 
2756 	np->np_context = NULL;
2757 	kfree(isert_np);
2758 }
2759 
2760 static void isert_wait_conn(struct iscsi_conn *conn)
2761 {
2762 	struct isert_conn *isert_conn = conn->context;
2763 
2764 	pr_debug("isert_wait_conn: Starting \n");
2765 	/*
2766 	 * Decrement post_send_buf_count for special case when called
2767 	 * from isert_do_control_comp() -> iscsit_logout_post_handler()
2768 	 */
2769 	mutex_lock(&isert_conn->conn_mutex);
2770 	if (isert_conn->logout_posted)
2771 		atomic_dec(&isert_conn->post_send_buf_count);
2772 
2773 	if (isert_conn->conn_cm_id && isert_conn->state != ISER_CONN_DOWN) {
2774 		pr_debug("Calling rdma_disconnect from isert_wait_conn\n");
2775 		rdma_disconnect(isert_conn->conn_cm_id);
2776 	}
2777 	/*
2778 	 * Only wait for conn_wait_comp_err if the isert_conn made it
2779 	 * into full feature phase..
2780 	 */
2781 	if (isert_conn->state == ISER_CONN_INIT) {
2782 		mutex_unlock(&isert_conn->conn_mutex);
2783 		return;
2784 	}
2785 	if (isert_conn->state == ISER_CONN_UP)
2786 		isert_conn->state = ISER_CONN_TERMINATING;
2787 	mutex_unlock(&isert_conn->conn_mutex);
2788 
2789 	wait_for_completion(&isert_conn->conn_wait_comp_err);
2790 
2791 	wait_for_completion(&isert_conn->conn_wait);
2792 }
2793 
2794 static void isert_free_conn(struct iscsi_conn *conn)
2795 {
2796 	struct isert_conn *isert_conn = conn->context;
2797 
2798 	isert_put_conn(isert_conn);
2799 }
2800 
2801 static struct iscsit_transport iser_target_transport = {
2802 	.name			= "IB/iSER",
2803 	.transport_type		= ISCSI_INFINIBAND,
2804 	.priv_size		= sizeof(struct isert_cmd),
2805 	.owner			= THIS_MODULE,
2806 	.iscsit_setup_np	= isert_setup_np,
2807 	.iscsit_accept_np	= isert_accept_np,
2808 	.iscsit_free_np		= isert_free_np,
2809 	.iscsit_wait_conn	= isert_wait_conn,
2810 	.iscsit_free_conn	= isert_free_conn,
2811 	.iscsit_get_login_rx	= isert_get_login_rx,
2812 	.iscsit_put_login_tx	= isert_put_login_tx,
2813 	.iscsit_immediate_queue	= isert_immediate_queue,
2814 	.iscsit_response_queue	= isert_response_queue,
2815 	.iscsit_get_dataout	= isert_get_dataout,
2816 	.iscsit_queue_data_in	= isert_put_datain,
2817 	.iscsit_queue_status	= isert_put_response,
2818 };
2819 
2820 static int __init isert_init(void)
2821 {
2822 	int ret;
2823 
2824 	isert_rx_wq = alloc_workqueue("isert_rx_wq", 0, 0);
2825 	if (!isert_rx_wq) {
2826 		pr_err("Unable to allocate isert_rx_wq\n");
2827 		return -ENOMEM;
2828 	}
2829 
2830 	isert_comp_wq = alloc_workqueue("isert_comp_wq", 0, 0);
2831 	if (!isert_comp_wq) {
2832 		pr_err("Unable to allocate isert_comp_wq\n");
2833 		ret = -ENOMEM;
2834 		goto destroy_rx_wq;
2835 	}
2836 
2837 	iscsit_register_transport(&iser_target_transport);
2838 	pr_debug("iSER_TARGET[0] - Loaded iser_target_transport\n");
2839 	return 0;
2840 
2841 destroy_rx_wq:
2842 	destroy_workqueue(isert_rx_wq);
2843 	return ret;
2844 }
2845 
2846 static void __exit isert_exit(void)
2847 {
2848 	destroy_workqueue(isert_comp_wq);
2849 	destroy_workqueue(isert_rx_wq);
2850 	iscsit_unregister_transport(&iser_target_transport);
2851 	pr_debug("iSER_TARGET[0] - Released iser_target_transport\n");
2852 }
2853 
2854 MODULE_DESCRIPTION("iSER-Target for mainline target infrastructure");
2855 MODULE_VERSION("0.1");
2856 MODULE_AUTHOR("nab@Linux-iSCSI.org");
2857 MODULE_LICENSE("GPL");
2858 
2859 module_init(isert_init);
2860 module_exit(isert_exit);
2861