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_waitqueue_head(&isert_conn->conn_wait);
496 	init_waitqueue_head(&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 	mutex_init(&isert_conn->conn_comp_mutex);
501 	spin_lock_init(&isert_conn->conn_lock);
502 
503 	cma_id->context = isert_conn;
504 	isert_conn->conn_cm_id = cma_id;
505 	isert_conn->responder_resources = event->param.conn.responder_resources;
506 	isert_conn->initiator_depth = event->param.conn.initiator_depth;
507 	pr_debug("Using responder_resources: %u initiator_depth: %u\n",
508 		 isert_conn->responder_resources, isert_conn->initiator_depth);
509 
510 	isert_conn->login_buf = kzalloc(ISCSI_DEF_MAX_RECV_SEG_LEN +
511 					ISER_RX_LOGIN_SIZE, GFP_KERNEL);
512 	if (!isert_conn->login_buf) {
513 		pr_err("Unable to allocate isert_conn->login_buf\n");
514 		ret = -ENOMEM;
515 		goto out;
516 	}
517 
518 	isert_conn->login_req_buf = isert_conn->login_buf;
519 	isert_conn->login_rsp_buf = isert_conn->login_buf +
520 				    ISCSI_DEF_MAX_RECV_SEG_LEN;
521 	pr_debug("Set login_buf: %p login_req_buf: %p login_rsp_buf: %p\n",
522 		 isert_conn->login_buf, isert_conn->login_req_buf,
523 		 isert_conn->login_rsp_buf);
524 
525 	isert_conn->login_req_dma = ib_dma_map_single(ib_dev,
526 				(void *)isert_conn->login_req_buf,
527 				ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
528 
529 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_req_dma);
530 	if (ret) {
531 		pr_err("ib_dma_mapping_error failed for login_req_dma: %d\n",
532 		       ret);
533 		isert_conn->login_req_dma = 0;
534 		goto out_login_buf;
535 	}
536 
537 	isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
538 					(void *)isert_conn->login_rsp_buf,
539 					ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
540 
541 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
542 	if (ret) {
543 		pr_err("ib_dma_mapping_error failed for login_rsp_dma: %d\n",
544 		       ret);
545 		isert_conn->login_rsp_dma = 0;
546 		goto out_req_dma_map;
547 	}
548 
549 	device = isert_device_find_by_ib_dev(cma_id);
550 	if (IS_ERR(device)) {
551 		ret = PTR_ERR(device);
552 		goto out_rsp_dma_map;
553 	}
554 
555 	isert_conn->conn_device = device;
556 	isert_conn->conn_pd = ib_alloc_pd(isert_conn->conn_device->ib_device);
557 	if (IS_ERR(isert_conn->conn_pd)) {
558 		ret = PTR_ERR(isert_conn->conn_pd);
559 		pr_err("ib_alloc_pd failed for conn %p: ret=%d\n",
560 		       isert_conn, ret);
561 		goto out_pd;
562 	}
563 
564 	isert_conn->conn_mr = ib_get_dma_mr(isert_conn->conn_pd,
565 					   IB_ACCESS_LOCAL_WRITE);
566 	if (IS_ERR(isert_conn->conn_mr)) {
567 		ret = PTR_ERR(isert_conn->conn_mr);
568 		pr_err("ib_get_dma_mr failed for conn %p: ret=%d\n",
569 		       isert_conn, ret);
570 		goto out_mr;
571 	}
572 
573 	if (device->use_fastreg) {
574 		ret = isert_conn_create_fastreg_pool(isert_conn);
575 		if (ret) {
576 			pr_err("Conn: %p failed to create fastreg pool\n",
577 			       isert_conn);
578 			goto out_fastreg;
579 		}
580 	}
581 
582 	ret = isert_conn_setup_qp(isert_conn, cma_id);
583 	if (ret)
584 		goto out_conn_dev;
585 
586 	mutex_lock(&isert_np->np_accept_mutex);
587 	list_add_tail(&isert_np->np_accept_list, &isert_conn->conn_accept_node);
588 	mutex_unlock(&isert_np->np_accept_mutex);
589 
590 	pr_debug("isert_connect_request() waking up np_accept_wq: %p\n", np);
591 	wake_up(&isert_np->np_accept_wq);
592 	return 0;
593 
594 out_conn_dev:
595 	if (device->use_fastreg)
596 		isert_conn_free_fastreg_pool(isert_conn);
597 out_fastreg:
598 	ib_dereg_mr(isert_conn->conn_mr);
599 out_mr:
600 	ib_dealloc_pd(isert_conn->conn_pd);
601 out_pd:
602 	isert_device_try_release(device);
603 out_rsp_dma_map:
604 	ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
605 			    ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
606 out_req_dma_map:
607 	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
608 			    ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
609 out_login_buf:
610 	kfree(isert_conn->login_buf);
611 out:
612 	kfree(isert_conn);
613 	return ret;
614 }
615 
616 static void
617 isert_connect_release(struct isert_conn *isert_conn)
618 {
619 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
620 	struct isert_device *device = isert_conn->conn_device;
621 	int cq_index;
622 
623 	pr_debug("Entering isert_connect_release(): >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
624 
625 	if (device && device->use_fastreg)
626 		isert_conn_free_fastreg_pool(isert_conn);
627 
628 	if (isert_conn->conn_qp) {
629 		cq_index = ((struct isert_cq_desc *)
630 			isert_conn->conn_qp->recv_cq->cq_context)->cq_index;
631 		pr_debug("isert_connect_release: cq_index: %d\n", cq_index);
632 		isert_conn->conn_device->cq_active_qps[cq_index]--;
633 
634 		rdma_destroy_qp(isert_conn->conn_cm_id);
635 	}
636 
637 	isert_free_rx_descriptors(isert_conn);
638 	rdma_destroy_id(isert_conn->conn_cm_id);
639 
640 	ib_dereg_mr(isert_conn->conn_mr);
641 	ib_dealloc_pd(isert_conn->conn_pd);
642 
643 	if (isert_conn->login_buf) {
644 		ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
645 				    ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
646 		ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
647 				    ISCSI_DEF_MAX_RECV_SEG_LEN,
648 				    DMA_FROM_DEVICE);
649 		kfree(isert_conn->login_buf);
650 	}
651 	kfree(isert_conn);
652 
653 	if (device)
654 		isert_device_try_release(device);
655 
656 	pr_debug("Leaving isert_connect_release >>>>>>>>>>>>\n");
657 }
658 
659 static void
660 isert_connected_handler(struct rdma_cm_id *cma_id)
661 {
662 	return;
663 }
664 
665 static void
666 isert_release_conn_kref(struct kref *kref)
667 {
668 	struct isert_conn *isert_conn = container_of(kref,
669 				struct isert_conn, conn_kref);
670 
671 	pr_debug("Calling isert_connect_release for final kref %s/%d\n",
672 		 current->comm, current->pid);
673 
674 	isert_connect_release(isert_conn);
675 }
676 
677 static void
678 isert_put_conn(struct isert_conn *isert_conn)
679 {
680 	kref_put(&isert_conn->conn_kref, isert_release_conn_kref);
681 }
682 
683 static void
684 isert_disconnect_work(struct work_struct *work)
685 {
686 	struct isert_conn *isert_conn = container_of(work,
687 				struct isert_conn, conn_logout_work);
688 
689 	pr_debug("isert_disconnect_work(): >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
690 	mutex_lock(&isert_conn->conn_mutex);
691 	isert_conn->state = ISER_CONN_DOWN;
692 
693 	if (isert_conn->post_recv_buf_count == 0 &&
694 	    atomic_read(&isert_conn->post_send_buf_count) == 0) {
695 		pr_debug("Calling wake_up(&isert_conn->conn_wait);\n");
696 		mutex_unlock(&isert_conn->conn_mutex);
697 		goto wake_up;
698 	}
699 	if (!isert_conn->conn_cm_id) {
700 		mutex_unlock(&isert_conn->conn_mutex);
701 		isert_put_conn(isert_conn);
702 		return;
703 	}
704 	if (!isert_conn->logout_posted) {
705 		pr_debug("Calling rdma_disconnect for !logout_posted from"
706 			 " isert_disconnect_work\n");
707 		rdma_disconnect(isert_conn->conn_cm_id);
708 		mutex_unlock(&isert_conn->conn_mutex);
709 		iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
710 		goto wake_up;
711 	}
712 	mutex_unlock(&isert_conn->conn_mutex);
713 
714 wake_up:
715 	wake_up(&isert_conn->conn_wait);
716 	isert_put_conn(isert_conn);
717 }
718 
719 static void
720 isert_disconnected_handler(struct rdma_cm_id *cma_id)
721 {
722 	struct isert_conn *isert_conn = (struct isert_conn *)cma_id->context;
723 
724 	INIT_WORK(&isert_conn->conn_logout_work, isert_disconnect_work);
725 	schedule_work(&isert_conn->conn_logout_work);
726 }
727 
728 static int
729 isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
730 {
731 	int ret = 0;
732 
733 	pr_debug("isert_cma_handler: event %d status %d conn %p id %p\n",
734 		 event->event, event->status, cma_id->context, cma_id);
735 
736 	switch (event->event) {
737 	case RDMA_CM_EVENT_CONNECT_REQUEST:
738 		pr_debug("RDMA_CM_EVENT_CONNECT_REQUEST: >>>>>>>>>>>>>>>\n");
739 		ret = isert_connect_request(cma_id, event);
740 		break;
741 	case RDMA_CM_EVENT_ESTABLISHED:
742 		pr_debug("RDMA_CM_EVENT_ESTABLISHED >>>>>>>>>>>>>>\n");
743 		isert_connected_handler(cma_id);
744 		break;
745 	case RDMA_CM_EVENT_DISCONNECTED:
746 		pr_debug("RDMA_CM_EVENT_DISCONNECTED: >>>>>>>>>>>>>>\n");
747 		isert_disconnected_handler(cma_id);
748 		break;
749 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
750 	case RDMA_CM_EVENT_ADDR_CHANGE:
751 		break;
752 	case RDMA_CM_EVENT_CONNECT_ERROR:
753 	default:
754 		pr_err("Unknown RDMA CMA event: %d\n", event->event);
755 		break;
756 	}
757 
758 	if (ret != 0) {
759 		pr_err("isert_cma_handler failed RDMA_CM_EVENT: 0x%08x %d\n",
760 		       event->event, ret);
761 		dump_stack();
762 	}
763 
764 	return ret;
765 }
766 
767 static int
768 isert_post_recv(struct isert_conn *isert_conn, u32 count)
769 {
770 	struct ib_recv_wr *rx_wr, *rx_wr_failed;
771 	int i, ret;
772 	unsigned int rx_head = isert_conn->conn_rx_desc_head;
773 	struct iser_rx_desc *rx_desc;
774 
775 	for (rx_wr = isert_conn->conn_rx_wr, i = 0; i < count; i++, rx_wr++) {
776 		rx_desc		= &isert_conn->conn_rx_descs[rx_head];
777 		rx_wr->wr_id	= (unsigned long)rx_desc;
778 		rx_wr->sg_list	= &rx_desc->rx_sg;
779 		rx_wr->num_sge	= 1;
780 		rx_wr->next	= rx_wr + 1;
781 		rx_head = (rx_head + 1) & (ISERT_QP_MAX_RECV_DTOS - 1);
782 	}
783 
784 	rx_wr--;
785 	rx_wr->next = NULL; /* mark end of work requests list */
786 
787 	isert_conn->post_recv_buf_count += count;
788 	ret = ib_post_recv(isert_conn->conn_qp, isert_conn->conn_rx_wr,
789 				&rx_wr_failed);
790 	if (ret) {
791 		pr_err("ib_post_recv() failed with ret: %d\n", ret);
792 		isert_conn->post_recv_buf_count -= count;
793 	} else {
794 		pr_debug("isert_post_recv(): Posted %d RX buffers\n", count);
795 		isert_conn->conn_rx_desc_head = rx_head;
796 	}
797 	return ret;
798 }
799 
800 static int
801 isert_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
802 {
803 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
804 	struct ib_send_wr send_wr, *send_wr_failed;
805 	int ret;
806 
807 	ib_dma_sync_single_for_device(ib_dev, tx_desc->dma_addr,
808 				      ISER_HEADERS_LEN, DMA_TO_DEVICE);
809 
810 	send_wr.next	= NULL;
811 	send_wr.wr_id	= (unsigned long)tx_desc;
812 	send_wr.sg_list	= tx_desc->tx_sg;
813 	send_wr.num_sge	= tx_desc->num_sge;
814 	send_wr.opcode	= IB_WR_SEND;
815 	send_wr.send_flags = IB_SEND_SIGNALED;
816 
817 	atomic_inc(&isert_conn->post_send_buf_count);
818 
819 	ret = ib_post_send(isert_conn->conn_qp, &send_wr, &send_wr_failed);
820 	if (ret) {
821 		pr_err("ib_post_send() failed, ret: %d\n", ret);
822 		atomic_dec(&isert_conn->post_send_buf_count);
823 	}
824 
825 	return ret;
826 }
827 
828 static void
829 isert_create_send_desc(struct isert_conn *isert_conn,
830 		       struct isert_cmd *isert_cmd,
831 		       struct iser_tx_desc *tx_desc)
832 {
833 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
834 
835 	ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr,
836 				   ISER_HEADERS_LEN, DMA_TO_DEVICE);
837 
838 	memset(&tx_desc->iser_header, 0, sizeof(struct iser_hdr));
839 	tx_desc->iser_header.flags = ISER_VER;
840 
841 	tx_desc->num_sge = 1;
842 	tx_desc->isert_cmd = isert_cmd;
843 
844 	if (tx_desc->tx_sg[0].lkey != isert_conn->conn_mr->lkey) {
845 		tx_desc->tx_sg[0].lkey = isert_conn->conn_mr->lkey;
846 		pr_debug("tx_desc %p lkey mismatch, fixing\n", tx_desc);
847 	}
848 }
849 
850 static int
851 isert_init_tx_hdrs(struct isert_conn *isert_conn,
852 		   struct iser_tx_desc *tx_desc)
853 {
854 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
855 	u64 dma_addr;
856 
857 	dma_addr = ib_dma_map_single(ib_dev, (void *)tx_desc,
858 			ISER_HEADERS_LEN, DMA_TO_DEVICE);
859 	if (ib_dma_mapping_error(ib_dev, dma_addr)) {
860 		pr_err("ib_dma_mapping_error() failed\n");
861 		return -ENOMEM;
862 	}
863 
864 	tx_desc->dma_addr = dma_addr;
865 	tx_desc->tx_sg[0].addr	= tx_desc->dma_addr;
866 	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
867 	tx_desc->tx_sg[0].lkey = isert_conn->conn_mr->lkey;
868 
869 	pr_debug("isert_init_tx_hdrs: Setup tx_sg[0].addr: 0x%llx length: %u"
870 		 " lkey: 0x%08x\n", tx_desc->tx_sg[0].addr,
871 		 tx_desc->tx_sg[0].length, tx_desc->tx_sg[0].lkey);
872 
873 	return 0;
874 }
875 
876 static void
877 isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
878 		   struct ib_send_wr *send_wr, bool coalesce)
879 {
880 	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
881 
882 	isert_cmd->rdma_wr.iser_ib_op = ISER_IB_SEND;
883 	send_wr->wr_id = (unsigned long)&isert_cmd->tx_desc;
884 	send_wr->opcode = IB_WR_SEND;
885 	send_wr->sg_list = &tx_desc->tx_sg[0];
886 	send_wr->num_sge = isert_cmd->tx_desc.num_sge;
887 	/*
888 	 * Coalesce send completion interrupts by only setting IB_SEND_SIGNALED
889 	 * bit for every ISERT_COMP_BATCH_COUNT number of ib_post_send() calls.
890 	 */
891 	mutex_lock(&isert_conn->conn_comp_mutex);
892 	if (coalesce &&
893 	    ++isert_conn->conn_comp_batch < ISERT_COMP_BATCH_COUNT) {
894 		llist_add(&tx_desc->comp_llnode, &isert_conn->conn_comp_llist);
895 		mutex_unlock(&isert_conn->conn_comp_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_comp_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(&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(&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(&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 
1553 	pr_debug("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
1554 	spin_lock_bh(&cmd->istate_lock);
1555 	cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1556 	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1557 	spin_unlock_bh(&cmd->istate_lock);
1558 
1559 	target_execute_cmd(se_cmd);
1560 }
1561 
1562 static void
1563 isert_do_control_comp(struct work_struct *work)
1564 {
1565 	struct isert_cmd *isert_cmd = container_of(work,
1566 			struct isert_cmd, comp_work);
1567 	struct isert_conn *isert_conn = isert_cmd->conn;
1568 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1569 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1570 
1571 	switch (cmd->i_state) {
1572 	case ISTATE_SEND_TASKMGTRSP:
1573 		pr_debug("Calling iscsit_tmr_post_handler >>>>>>>>>>>>>>>>>\n");
1574 
1575 		atomic_dec(&isert_conn->post_send_buf_count);
1576 		iscsit_tmr_post_handler(cmd, cmd->conn);
1577 
1578 		cmd->i_state = ISTATE_SENT_STATUS;
1579 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd, ib_dev);
1580 		break;
1581 	case ISTATE_SEND_REJECT:
1582 		pr_debug("Got isert_do_control_comp ISTATE_SEND_REJECT: >>>\n");
1583 		atomic_dec(&isert_conn->post_send_buf_count);
1584 
1585 		cmd->i_state = ISTATE_SENT_STATUS;
1586 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd, ib_dev);
1587 		break;
1588 	case ISTATE_SEND_LOGOUTRSP:
1589 		pr_debug("Calling iscsit_logout_post_handler >>>>>>>>>>>>>>\n");
1590 		/*
1591 		 * Call atomic_dec(&isert_conn->post_send_buf_count)
1592 		 * from isert_free_conn()
1593 		 */
1594 		isert_conn->logout_posted = true;
1595 		iscsit_logout_post_handler(cmd, cmd->conn);
1596 		break;
1597 	case ISTATE_SEND_TEXTRSP:
1598 		atomic_dec(&isert_conn->post_send_buf_count);
1599 		cmd->i_state = ISTATE_SENT_STATUS;
1600 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd, ib_dev);
1601 		break;
1602 	default:
1603 		pr_err("Unknown do_control_comp i_state %d\n", cmd->i_state);
1604 		dump_stack();
1605 		break;
1606 	}
1607 }
1608 
1609 static void
1610 isert_response_completion(struct iser_tx_desc *tx_desc,
1611 			  struct isert_cmd *isert_cmd,
1612 			  struct isert_conn *isert_conn,
1613 			  struct ib_device *ib_dev)
1614 {
1615 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1616 
1617 	if (cmd->i_state == ISTATE_SEND_TASKMGTRSP ||
1618 	    cmd->i_state == ISTATE_SEND_LOGOUTRSP ||
1619 	    cmd->i_state == ISTATE_SEND_REJECT ||
1620 	    cmd->i_state == ISTATE_SEND_TEXTRSP) {
1621 		isert_unmap_tx_desc(tx_desc, ib_dev);
1622 
1623 		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
1624 		queue_work(isert_comp_wq, &isert_cmd->comp_work);
1625 		return;
1626 	}
1627 	atomic_dec(&isert_conn->post_send_buf_count);
1628 
1629 	cmd->i_state = ISTATE_SENT_STATUS;
1630 	isert_completion_put(tx_desc, isert_cmd, ib_dev);
1631 }
1632 
1633 static void
1634 __isert_send_completion(struct iser_tx_desc *tx_desc,
1635 		        struct isert_conn *isert_conn)
1636 {
1637 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1638 	struct isert_cmd *isert_cmd = tx_desc->isert_cmd;
1639 	struct isert_rdma_wr *wr;
1640 
1641 	if (!isert_cmd) {
1642 		atomic_dec(&isert_conn->post_send_buf_count);
1643 		isert_unmap_tx_desc(tx_desc, ib_dev);
1644 		return;
1645 	}
1646 	wr = &isert_cmd->rdma_wr;
1647 
1648 	switch (wr->iser_ib_op) {
1649 	case ISER_IB_RECV:
1650 		pr_err("isert_send_completion: Got ISER_IB_RECV\n");
1651 		dump_stack();
1652 		break;
1653 	case ISER_IB_SEND:
1654 		pr_debug("isert_send_completion: Got ISER_IB_SEND\n");
1655 		isert_response_completion(tx_desc, isert_cmd,
1656 					  isert_conn, ib_dev);
1657 		break;
1658 	case ISER_IB_RDMA_WRITE:
1659 		pr_err("isert_send_completion: Got ISER_IB_RDMA_WRITE\n");
1660 		dump_stack();
1661 		break;
1662 	case ISER_IB_RDMA_READ:
1663 		pr_debug("isert_send_completion: Got ISER_IB_RDMA_READ:\n");
1664 
1665 		atomic_dec(&isert_conn->post_send_buf_count);
1666 		isert_completion_rdma_read(tx_desc, isert_cmd);
1667 		break;
1668 	default:
1669 		pr_err("Unknown wr->iser_ib_op: 0x%02x\n", wr->iser_ib_op);
1670 		dump_stack();
1671 		break;
1672 	}
1673 }
1674 
1675 static void
1676 isert_send_completion(struct iser_tx_desc *tx_desc,
1677 		      struct isert_conn *isert_conn)
1678 {
1679 	struct llist_node *llnode = tx_desc->comp_llnode_batch;
1680 	struct iser_tx_desc *t;
1681 	/*
1682 	 * Drain coalesced completion llist starting from comp_llnode_batch
1683 	 * setup in isert_init_send_wr(), and then complete trailing tx_desc.
1684 	 */
1685 	while (llnode) {
1686 		t = llist_entry(llnode, struct iser_tx_desc, comp_llnode);
1687 		llnode = llist_next(llnode);
1688 		__isert_send_completion(t, isert_conn);
1689 	}
1690 	__isert_send_completion(tx_desc, isert_conn);
1691 }
1692 
1693 static void
1694 isert_cq_comp_err(struct iser_tx_desc *tx_desc, struct isert_conn *isert_conn)
1695 {
1696 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1697 
1698 	if (tx_desc) {
1699 		struct isert_cmd *isert_cmd = tx_desc->isert_cmd;
1700 
1701 		if (!isert_cmd)
1702 			isert_unmap_tx_desc(tx_desc, ib_dev);
1703 		else
1704 			isert_completion_put(tx_desc, isert_cmd, ib_dev);
1705 	}
1706 
1707 	if (isert_conn->post_recv_buf_count == 0 &&
1708 	    atomic_read(&isert_conn->post_send_buf_count) == 0) {
1709 		pr_debug("isert_cq_comp_err >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1710 		pr_debug("Calling wake_up from isert_cq_comp_err\n");
1711 
1712 		mutex_lock(&isert_conn->conn_mutex);
1713 		if (isert_conn->state != ISER_CONN_DOWN)
1714 			isert_conn->state = ISER_CONN_TERMINATING;
1715 		mutex_unlock(&isert_conn->conn_mutex);
1716 
1717 		wake_up(&isert_conn->conn_wait_comp_err);
1718 	}
1719 }
1720 
1721 static void
1722 isert_cq_tx_work(struct work_struct *work)
1723 {
1724 	struct isert_cq_desc *cq_desc = container_of(work,
1725 				struct isert_cq_desc, cq_tx_work);
1726 	struct isert_device *device = cq_desc->device;
1727 	int cq_index = cq_desc->cq_index;
1728 	struct ib_cq *tx_cq = device->dev_tx_cq[cq_index];
1729 	struct isert_conn *isert_conn;
1730 	struct iser_tx_desc *tx_desc;
1731 	struct ib_wc wc;
1732 
1733 	while (ib_poll_cq(tx_cq, 1, &wc) == 1) {
1734 		tx_desc = (struct iser_tx_desc *)(unsigned long)wc.wr_id;
1735 		isert_conn = wc.qp->qp_context;
1736 
1737 		if (wc.status == IB_WC_SUCCESS) {
1738 			isert_send_completion(tx_desc, isert_conn);
1739 		} else {
1740 			pr_debug("TX wc.status != IB_WC_SUCCESS >>>>>>>>>>>>>>\n");
1741 			pr_debug("TX wc.status: 0x%08x\n", wc.status);
1742 			pr_debug("TX wc.vendor_err: 0x%08x\n", wc.vendor_err);
1743 			atomic_dec(&isert_conn->post_send_buf_count);
1744 			isert_cq_comp_err(tx_desc, isert_conn);
1745 		}
1746 	}
1747 
1748 	ib_req_notify_cq(tx_cq, IB_CQ_NEXT_COMP);
1749 }
1750 
1751 static void
1752 isert_cq_tx_callback(struct ib_cq *cq, void *context)
1753 {
1754 	struct isert_cq_desc *cq_desc = (struct isert_cq_desc *)context;
1755 
1756 	queue_work(isert_comp_wq, &cq_desc->cq_tx_work);
1757 }
1758 
1759 static void
1760 isert_cq_rx_work(struct work_struct *work)
1761 {
1762 	struct isert_cq_desc *cq_desc = container_of(work,
1763 			struct isert_cq_desc, cq_rx_work);
1764 	struct isert_device *device = cq_desc->device;
1765 	int cq_index = cq_desc->cq_index;
1766 	struct ib_cq *rx_cq = device->dev_rx_cq[cq_index];
1767 	struct isert_conn *isert_conn;
1768 	struct iser_rx_desc *rx_desc;
1769 	struct ib_wc wc;
1770 	unsigned long xfer_len;
1771 
1772 	while (ib_poll_cq(rx_cq, 1, &wc) == 1) {
1773 		rx_desc = (struct iser_rx_desc *)(unsigned long)wc.wr_id;
1774 		isert_conn = wc.qp->qp_context;
1775 
1776 		if (wc.status == IB_WC_SUCCESS) {
1777 			xfer_len = (unsigned long)wc.byte_len;
1778 			isert_rx_completion(rx_desc, isert_conn, xfer_len);
1779 		} else {
1780 			pr_debug("RX wc.status != IB_WC_SUCCESS >>>>>>>>>>>>>>\n");
1781 			if (wc.status != IB_WC_WR_FLUSH_ERR) {
1782 				pr_debug("RX wc.status: 0x%08x\n", wc.status);
1783 				pr_debug("RX wc.vendor_err: 0x%08x\n",
1784 					 wc.vendor_err);
1785 			}
1786 			isert_conn->post_recv_buf_count--;
1787 			isert_cq_comp_err(NULL, isert_conn);
1788 		}
1789 	}
1790 
1791 	ib_req_notify_cq(rx_cq, IB_CQ_NEXT_COMP);
1792 }
1793 
1794 static void
1795 isert_cq_rx_callback(struct ib_cq *cq, void *context)
1796 {
1797 	struct isert_cq_desc *cq_desc = (struct isert_cq_desc *)context;
1798 
1799 	queue_work(isert_rx_wq, &cq_desc->cq_rx_work);
1800 }
1801 
1802 static int
1803 isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
1804 {
1805 	struct ib_send_wr *wr_failed;
1806 	int ret;
1807 
1808 	atomic_inc(&isert_conn->post_send_buf_count);
1809 
1810 	ret = ib_post_send(isert_conn->conn_qp, &isert_cmd->tx_desc.send_wr,
1811 			   &wr_failed);
1812 	if (ret) {
1813 		pr_err("ib_post_send failed with %d\n", ret);
1814 		atomic_dec(&isert_conn->post_send_buf_count);
1815 		return ret;
1816 	}
1817 	return ret;
1818 }
1819 
1820 static int
1821 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
1822 {
1823 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1824 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1825 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1826 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
1827 				&isert_cmd->tx_desc.iscsi_header;
1828 
1829 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1830 	iscsit_build_rsp_pdu(cmd, conn, true, hdr);
1831 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1832 	/*
1833 	 * Attach SENSE DATA payload to iSCSI Response PDU
1834 	 */
1835 	if (cmd->se_cmd.sense_buffer &&
1836 	    ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1837 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
1838 		struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1839 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1840 		u32 padding, pdu_len;
1841 
1842 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length,
1843 				   cmd->sense_buffer);
1844 		cmd->se_cmd.scsi_sense_length += sizeof(__be16);
1845 
1846 		padding = -(cmd->se_cmd.scsi_sense_length) & 3;
1847 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
1848 		pdu_len = cmd->se_cmd.scsi_sense_length + padding;
1849 
1850 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1851 				(void *)cmd->sense_buffer, pdu_len,
1852 				DMA_TO_DEVICE);
1853 
1854 		isert_cmd->pdu_buf_len = pdu_len;
1855 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1856 		tx_dsg->length	= pdu_len;
1857 		tx_dsg->lkey	= isert_conn->conn_mr->lkey;
1858 		isert_cmd->tx_desc.num_sge = 2;
1859 	}
1860 
1861 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, true);
1862 
1863 	pr_debug("Posting SCSI Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1864 
1865 	return isert_post_response(isert_conn, isert_cmd);
1866 }
1867 
1868 static int
1869 isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
1870 		bool nopout_response)
1871 {
1872 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1873 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1874 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1875 
1876 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1877 	iscsit_build_nopin_rsp(cmd, conn, (struct iscsi_nopin *)
1878 			       &isert_cmd->tx_desc.iscsi_header,
1879 			       nopout_response);
1880 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1881 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1882 
1883 	pr_debug("Posting NOPIN Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1884 
1885 	return isert_post_response(isert_conn, isert_cmd);
1886 }
1887 
1888 static int
1889 isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1890 {
1891 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1892 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1893 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1894 
1895 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1896 	iscsit_build_logout_rsp(cmd, conn, (struct iscsi_logout_rsp *)
1897 				&isert_cmd->tx_desc.iscsi_header);
1898 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1899 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1900 
1901 	pr_debug("Posting Logout Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1902 
1903 	return isert_post_response(isert_conn, isert_cmd);
1904 }
1905 
1906 static int
1907 isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1908 {
1909 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1910 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1911 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1912 
1913 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1914 	iscsit_build_task_mgt_rsp(cmd, conn, (struct iscsi_tm_rsp *)
1915 				  &isert_cmd->tx_desc.iscsi_header);
1916 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1917 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1918 
1919 	pr_debug("Posting Task Management Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1920 
1921 	return isert_post_response(isert_conn, isert_cmd);
1922 }
1923 
1924 static int
1925 isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1926 {
1927 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1928 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1929 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1930 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1931 	struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1932 	struct iscsi_reject *hdr =
1933 		(struct iscsi_reject *)&isert_cmd->tx_desc.iscsi_header;
1934 
1935 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1936 	iscsit_build_reject(cmd, conn, hdr);
1937 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1938 
1939 	hton24(hdr->dlength, ISCSI_HDR_LEN);
1940 	isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1941 			(void *)cmd->buf_ptr, ISCSI_HDR_LEN,
1942 			DMA_TO_DEVICE);
1943 	isert_cmd->pdu_buf_len = ISCSI_HDR_LEN;
1944 	tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1945 	tx_dsg->length	= ISCSI_HDR_LEN;
1946 	tx_dsg->lkey	= isert_conn->conn_mr->lkey;
1947 	isert_cmd->tx_desc.num_sge = 2;
1948 
1949 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1950 
1951 	pr_debug("Posting Reject IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1952 
1953 	return isert_post_response(isert_conn, isert_cmd);
1954 }
1955 
1956 static int
1957 isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
1958 {
1959 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1960 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
1961 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1962 	struct iscsi_text_rsp *hdr =
1963 		(struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1964 	u32 txt_rsp_len;
1965 	int rc;
1966 
1967 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1968 	rc = iscsit_build_text_rsp(cmd, conn, hdr);
1969 	if (rc < 0)
1970 		return rc;
1971 
1972 	txt_rsp_len = rc;
1973 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1974 
1975 	if (txt_rsp_len) {
1976 		struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
1977 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1978 		void *txt_rsp_buf = cmd->buf_ptr;
1979 
1980 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1981 				txt_rsp_buf, txt_rsp_len, DMA_TO_DEVICE);
1982 
1983 		isert_cmd->pdu_buf_len = txt_rsp_len;
1984 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1985 		tx_dsg->length	= txt_rsp_len;
1986 		tx_dsg->lkey	= isert_conn->conn_mr->lkey;
1987 		isert_cmd->tx_desc.num_sge = 2;
1988 	}
1989 	isert_init_send_wr(isert_conn, isert_cmd, send_wr, false);
1990 
1991 	pr_debug("Posting Text Response IB_WR_SEND >>>>>>>>>>>>>>>>>>>>>>\n");
1992 
1993 	return isert_post_response(isert_conn, isert_cmd);
1994 }
1995 
1996 static int
1997 isert_build_rdma_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1998 		    struct ib_sge *ib_sge, struct ib_send_wr *send_wr,
1999 		    u32 data_left, u32 offset)
2000 {
2001 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
2002 	struct scatterlist *sg_start, *tmp_sg;
2003 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2004 	u32 sg_off, page_off;
2005 	int i = 0, sg_nents;
2006 
2007 	sg_off = offset / PAGE_SIZE;
2008 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
2009 	sg_nents = min(cmd->se_cmd.t_data_nents - sg_off, isert_conn->max_sge);
2010 	page_off = offset % PAGE_SIZE;
2011 
2012 	send_wr->sg_list = ib_sge;
2013 	send_wr->num_sge = sg_nents;
2014 	send_wr->wr_id = (unsigned long)&isert_cmd->tx_desc;
2015 	/*
2016 	 * Perform mapping of TCM scatterlist memory ib_sge dma_addr.
2017 	 */
2018 	for_each_sg(sg_start, tmp_sg, sg_nents, i) {
2019 		pr_debug("ISER RDMA from SGL dma_addr: 0x%16llx dma_len: %u, page_off: %u\n",
2020 			 (unsigned long long)tmp_sg->dma_address,
2021 			 tmp_sg->length, page_off);
2022 
2023 		ib_sge->addr = ib_sg_dma_address(ib_dev, tmp_sg) + page_off;
2024 		ib_sge->length = min_t(u32, data_left,
2025 				ib_sg_dma_len(ib_dev, tmp_sg) - page_off);
2026 		ib_sge->lkey = isert_conn->conn_mr->lkey;
2027 
2028 		pr_debug("RDMA ib_sge: addr: 0x%16llx  length: %u lkey: %08x\n",
2029 			 ib_sge->addr, ib_sge->length, ib_sge->lkey);
2030 		page_off = 0;
2031 		data_left -= ib_sge->length;
2032 		ib_sge++;
2033 		pr_debug("Incrementing ib_sge pointer to %p\n", ib_sge);
2034 	}
2035 
2036 	pr_debug("Set outgoing sg_list: %p num_sg: %u from TCM SGLs\n",
2037 		 send_wr->sg_list, send_wr->num_sge);
2038 
2039 	return sg_nents;
2040 }
2041 
2042 static int
2043 isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2044 	       struct isert_rdma_wr *wr)
2045 {
2046 	struct se_cmd *se_cmd = &cmd->se_cmd;
2047 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2048 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2049 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2050 	struct ib_send_wr *send_wr;
2051 	struct ib_sge *ib_sge;
2052 	struct scatterlist *sg_start;
2053 	u32 sg_off = 0, sg_nents;
2054 	u32 offset = 0, data_len, data_left, rdma_write_max, va_offset = 0;
2055 	int ret = 0, count, i, ib_sge_cnt;
2056 
2057 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2058 		data_left = se_cmd->data_length;
2059 	} else {
2060 		sg_off = cmd->write_data_done / PAGE_SIZE;
2061 		data_left = se_cmd->data_length - cmd->write_data_done;
2062 		offset = cmd->write_data_done;
2063 		isert_cmd->tx_desc.isert_cmd = isert_cmd;
2064 	}
2065 
2066 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
2067 	sg_nents = se_cmd->t_data_nents - sg_off;
2068 
2069 	count = ib_dma_map_sg(ib_dev, sg_start, sg_nents,
2070 			      (wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2071 			      DMA_TO_DEVICE : DMA_FROM_DEVICE);
2072 	if (unlikely(!count)) {
2073 		pr_err("Cmd: %p unrable to map SGs\n", isert_cmd);
2074 		return -EINVAL;
2075 	}
2076 	wr->sge = sg_start;
2077 	wr->num_sge = sg_nents;
2078 	wr->cur_rdma_length = data_left;
2079 	pr_debug("Mapped cmd: %p count: %u sg: %p sg_nents: %u rdma_len %d\n",
2080 		 isert_cmd, count, sg_start, sg_nents, data_left);
2081 
2082 	ib_sge = kzalloc(sizeof(struct ib_sge) * sg_nents, GFP_KERNEL);
2083 	if (!ib_sge) {
2084 		pr_warn("Unable to allocate ib_sge\n");
2085 		ret = -ENOMEM;
2086 		goto unmap_sg;
2087 	}
2088 	wr->ib_sge = ib_sge;
2089 
2090 	wr->send_wr_num = DIV_ROUND_UP(sg_nents, isert_conn->max_sge);
2091 	wr->send_wr = kzalloc(sizeof(struct ib_send_wr) * wr->send_wr_num,
2092 				GFP_KERNEL);
2093 	if (!wr->send_wr) {
2094 		pr_debug("Unable to allocate wr->send_wr\n");
2095 		ret = -ENOMEM;
2096 		goto unmap_sg;
2097 	}
2098 
2099 	wr->isert_cmd = isert_cmd;
2100 	rdma_write_max = isert_conn->max_sge * PAGE_SIZE;
2101 
2102 	for (i = 0; i < wr->send_wr_num; i++) {
2103 		send_wr = &isert_cmd->rdma_wr.send_wr[i];
2104 		data_len = min(data_left, rdma_write_max);
2105 
2106 		send_wr->send_flags = 0;
2107 		if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2108 			send_wr->opcode = IB_WR_RDMA_WRITE;
2109 			send_wr->wr.rdma.remote_addr = isert_cmd->read_va + offset;
2110 			send_wr->wr.rdma.rkey = isert_cmd->read_stag;
2111 			if (i + 1 == wr->send_wr_num)
2112 				send_wr->next = &isert_cmd->tx_desc.send_wr;
2113 			else
2114 				send_wr->next = &wr->send_wr[i + 1];
2115 		} else {
2116 			send_wr->opcode = IB_WR_RDMA_READ;
2117 			send_wr->wr.rdma.remote_addr = isert_cmd->write_va + va_offset;
2118 			send_wr->wr.rdma.rkey = isert_cmd->write_stag;
2119 			if (i + 1 == wr->send_wr_num)
2120 				send_wr->send_flags = IB_SEND_SIGNALED;
2121 			else
2122 				send_wr->next = &wr->send_wr[i + 1];
2123 		}
2124 
2125 		ib_sge_cnt = isert_build_rdma_wr(isert_conn, isert_cmd, ib_sge,
2126 					send_wr, data_len, offset);
2127 		ib_sge += ib_sge_cnt;
2128 
2129 		offset += data_len;
2130 		va_offset += data_len;
2131 		data_left -= data_len;
2132 	}
2133 
2134 	return 0;
2135 unmap_sg:
2136 	ib_dma_unmap_sg(ib_dev, sg_start, sg_nents,
2137 			(wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2138 			DMA_TO_DEVICE : DMA_FROM_DEVICE);
2139 	return ret;
2140 }
2141 
2142 static int
2143 isert_map_fr_pagelist(struct ib_device *ib_dev,
2144 		      struct scatterlist *sg_start, int sg_nents, u64 *fr_pl)
2145 {
2146 	u64 start_addr, end_addr, page, chunk_start = 0;
2147 	struct scatterlist *tmp_sg;
2148 	int i = 0, new_chunk, last_ent, n_pages;
2149 
2150 	n_pages = 0;
2151 	new_chunk = 1;
2152 	last_ent = sg_nents - 1;
2153 	for_each_sg(sg_start, tmp_sg, sg_nents, i) {
2154 		start_addr = ib_sg_dma_address(ib_dev, tmp_sg);
2155 		if (new_chunk)
2156 			chunk_start = start_addr;
2157 		end_addr = start_addr + ib_sg_dma_len(ib_dev, tmp_sg);
2158 
2159 		pr_debug("SGL[%d] dma_addr: 0x%16llx len: %u\n",
2160 			 i, (unsigned long long)tmp_sg->dma_address,
2161 			 tmp_sg->length);
2162 
2163 		if ((end_addr & ~PAGE_MASK) && i < last_ent) {
2164 			new_chunk = 0;
2165 			continue;
2166 		}
2167 		new_chunk = 1;
2168 
2169 		page = chunk_start & PAGE_MASK;
2170 		do {
2171 			fr_pl[n_pages++] = page;
2172 			pr_debug("Mapped page_list[%d] page_addr: 0x%16llx\n",
2173 				 n_pages - 1, page);
2174 			page += PAGE_SIZE;
2175 		} while (page < end_addr);
2176 	}
2177 
2178 	return n_pages;
2179 }
2180 
2181 static int
2182 isert_fast_reg_mr(struct fast_reg_descriptor *fr_desc,
2183 		  struct isert_conn *isert_conn, struct scatterlist *sg_start,
2184 		  struct ib_sge *ib_sge, u32 sg_nents, u32 offset,
2185 		  unsigned int data_len)
2186 {
2187 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2188 	struct ib_send_wr fr_wr, inv_wr;
2189 	struct ib_send_wr *bad_wr, *wr = NULL;
2190 	int ret, pagelist_len;
2191 	u32 page_off;
2192 	u8 key;
2193 
2194 	sg_nents = min_t(unsigned int, sg_nents, ISCSI_ISER_SG_TABLESIZE);
2195 	page_off = offset % PAGE_SIZE;
2196 
2197 	pr_debug("Use fr_desc %p sg_nents %d offset %u\n",
2198 		 fr_desc, sg_nents, offset);
2199 
2200 	pagelist_len = isert_map_fr_pagelist(ib_dev, sg_start, sg_nents,
2201 					     &fr_desc->data_frpl->page_list[0]);
2202 
2203 	if (!fr_desc->valid) {
2204 		memset(&inv_wr, 0, sizeof(inv_wr));
2205 		inv_wr.opcode = IB_WR_LOCAL_INV;
2206 		inv_wr.ex.invalidate_rkey = fr_desc->data_mr->rkey;
2207 		wr = &inv_wr;
2208 		/* Bump the key */
2209 		key = (u8)(fr_desc->data_mr->rkey & 0x000000FF);
2210 		ib_update_fast_reg_key(fr_desc->data_mr, ++key);
2211 	}
2212 
2213 	/* Prepare FASTREG WR */
2214 	memset(&fr_wr, 0, sizeof(fr_wr));
2215 	fr_wr.opcode = IB_WR_FAST_REG_MR;
2216 	fr_wr.wr.fast_reg.iova_start =
2217 		fr_desc->data_frpl->page_list[0] + page_off;
2218 	fr_wr.wr.fast_reg.page_list = fr_desc->data_frpl;
2219 	fr_wr.wr.fast_reg.page_list_len = pagelist_len;
2220 	fr_wr.wr.fast_reg.page_shift = PAGE_SHIFT;
2221 	fr_wr.wr.fast_reg.length = data_len;
2222 	fr_wr.wr.fast_reg.rkey = fr_desc->data_mr->rkey;
2223 	fr_wr.wr.fast_reg.access_flags = IB_ACCESS_LOCAL_WRITE;
2224 
2225 	if (!wr)
2226 		wr = &fr_wr;
2227 	else
2228 		wr->next = &fr_wr;
2229 
2230 	ret = ib_post_send(isert_conn->conn_qp, wr, &bad_wr);
2231 	if (ret) {
2232 		pr_err("fast registration failed, ret:%d\n", ret);
2233 		return ret;
2234 	}
2235 	fr_desc->valid = false;
2236 
2237 	ib_sge->lkey = fr_desc->data_mr->lkey;
2238 	ib_sge->addr = fr_desc->data_frpl->page_list[0] + page_off;
2239 	ib_sge->length = data_len;
2240 
2241 	pr_debug("RDMA ib_sge: addr: 0x%16llx  length: %u lkey: %08x\n",
2242 		 ib_sge->addr, ib_sge->length, ib_sge->lkey);
2243 
2244 	return ret;
2245 }
2246 
2247 static int
2248 isert_reg_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2249 	       struct isert_rdma_wr *wr)
2250 {
2251 	struct se_cmd *se_cmd = &cmd->se_cmd;
2252 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2253 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2254 	struct ib_device *ib_dev = isert_conn->conn_cm_id->device;
2255 	struct ib_send_wr *send_wr;
2256 	struct ib_sge *ib_sge;
2257 	struct scatterlist *sg_start;
2258 	struct fast_reg_descriptor *fr_desc;
2259 	u32 sg_off = 0, sg_nents;
2260 	u32 offset = 0, data_len, data_left, rdma_write_max;
2261 	int ret = 0, count;
2262 	unsigned long flags;
2263 
2264 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2265 		data_left = se_cmd->data_length;
2266 	} else {
2267 		offset = cmd->write_data_done;
2268 		sg_off = offset / PAGE_SIZE;
2269 		data_left = se_cmd->data_length - cmd->write_data_done;
2270 		isert_cmd->tx_desc.isert_cmd = isert_cmd;
2271 	}
2272 
2273 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
2274 	sg_nents = se_cmd->t_data_nents - sg_off;
2275 
2276 	count = ib_dma_map_sg(ib_dev, sg_start, sg_nents,
2277 			      (wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2278 			      DMA_TO_DEVICE : DMA_FROM_DEVICE);
2279 	if (unlikely(!count)) {
2280 		pr_err("Cmd: %p unrable to map SGs\n", isert_cmd);
2281 		return -EINVAL;
2282 	}
2283 	wr->sge = sg_start;
2284 	wr->num_sge = sg_nents;
2285 	pr_debug("Mapped cmd: %p count: %u sg: %p sg_nents: %u rdma_len %d\n",
2286 		 isert_cmd, count, sg_start, sg_nents, data_left);
2287 
2288 	memset(&wr->s_ib_sge, 0, sizeof(*ib_sge));
2289 	ib_sge = &wr->s_ib_sge;
2290 	wr->ib_sge = ib_sge;
2291 
2292 	wr->send_wr_num = 1;
2293 	memset(&wr->s_send_wr, 0, sizeof(*send_wr));
2294 	wr->send_wr = &wr->s_send_wr;
2295 
2296 	wr->isert_cmd = isert_cmd;
2297 	rdma_write_max = ISCSI_ISER_SG_TABLESIZE * PAGE_SIZE;
2298 
2299 	send_wr = &isert_cmd->rdma_wr.s_send_wr;
2300 	send_wr->sg_list = ib_sge;
2301 	send_wr->num_sge = 1;
2302 	send_wr->wr_id = (unsigned long)&isert_cmd->tx_desc;
2303 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2304 		send_wr->opcode = IB_WR_RDMA_WRITE;
2305 		send_wr->wr.rdma.remote_addr = isert_cmd->read_va;
2306 		send_wr->wr.rdma.rkey = isert_cmd->read_stag;
2307 		send_wr->send_flags = 0;
2308 		send_wr->next = &isert_cmd->tx_desc.send_wr;
2309 	} else {
2310 		send_wr->opcode = IB_WR_RDMA_READ;
2311 		send_wr->wr.rdma.remote_addr = isert_cmd->write_va;
2312 		send_wr->wr.rdma.rkey = isert_cmd->write_stag;
2313 		send_wr->send_flags = IB_SEND_SIGNALED;
2314 	}
2315 
2316 	data_len = min(data_left, rdma_write_max);
2317 	wr->cur_rdma_length = data_len;
2318 
2319 	/* if there is a single dma entry, dma mr is sufficient */
2320 	if (count == 1) {
2321 		ib_sge->addr = ib_sg_dma_address(ib_dev, &sg_start[0]);
2322 		ib_sge->length = ib_sg_dma_len(ib_dev, &sg_start[0]);
2323 		ib_sge->lkey = isert_conn->conn_mr->lkey;
2324 		wr->fr_desc = NULL;
2325 	} else {
2326 		spin_lock_irqsave(&isert_conn->conn_lock, flags);
2327 		fr_desc = list_first_entry(&isert_conn->conn_fr_pool,
2328 					   struct fast_reg_descriptor, list);
2329 		list_del(&fr_desc->list);
2330 		spin_unlock_irqrestore(&isert_conn->conn_lock, flags);
2331 		wr->fr_desc = fr_desc;
2332 
2333 		ret = isert_fast_reg_mr(fr_desc, isert_conn, sg_start,
2334 					ib_sge, sg_nents, offset, data_len);
2335 		if (ret) {
2336 			list_add_tail(&fr_desc->list, &isert_conn->conn_fr_pool);
2337 			goto unmap_sg;
2338 		}
2339 	}
2340 
2341 	return 0;
2342 
2343 unmap_sg:
2344 	ib_dma_unmap_sg(ib_dev, sg_start, sg_nents,
2345 			(wr->iser_ib_op == ISER_IB_RDMA_WRITE) ?
2346 			DMA_TO_DEVICE : DMA_FROM_DEVICE);
2347 	return ret;
2348 }
2349 
2350 static int
2351 isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
2352 {
2353 	struct se_cmd *se_cmd = &cmd->se_cmd;
2354 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2355 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
2356 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2357 	struct isert_device *device = isert_conn->conn_device;
2358 	struct ib_send_wr *wr_failed;
2359 	int rc;
2360 
2361 	pr_debug("Cmd: %p RDMA_WRITE data_length: %u\n",
2362 		 isert_cmd, se_cmd->data_length);
2363 	wr->iser_ib_op = ISER_IB_RDMA_WRITE;
2364 	rc = device->reg_rdma_mem(conn, cmd, wr);
2365 	if (rc) {
2366 		pr_err("Cmd: %p failed to prepare RDMA res\n", isert_cmd);
2367 		return rc;
2368 	}
2369 
2370 	/*
2371 	 * Build isert_conn->tx_desc for iSCSI response PDU and attach
2372 	 */
2373 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2374 	iscsit_build_rsp_pdu(cmd, conn, true, (struct iscsi_scsi_rsp *)
2375 			     &isert_cmd->tx_desc.iscsi_header);
2376 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2377 	isert_init_send_wr(isert_conn, isert_cmd,
2378 			   &isert_cmd->tx_desc.send_wr, true);
2379 
2380 	atomic_inc(&isert_conn->post_send_buf_count);
2381 
2382 	rc = ib_post_send(isert_conn->conn_qp, wr->send_wr, &wr_failed);
2383 	if (rc) {
2384 		pr_warn("ib_post_send() failed for IB_WR_RDMA_WRITE\n");
2385 		atomic_dec(&isert_conn->post_send_buf_count);
2386 	}
2387 	pr_debug("Cmd: %p posted RDMA_WRITE + Response for iSER Data READ\n",
2388 		 isert_cmd);
2389 
2390 	return 1;
2391 }
2392 
2393 static int
2394 isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
2395 {
2396 	struct se_cmd *se_cmd = &cmd->se_cmd;
2397 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2398 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
2399 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2400 	struct isert_device *device = isert_conn->conn_device;
2401 	struct ib_send_wr *wr_failed;
2402 	int rc;
2403 
2404 	pr_debug("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
2405 		 isert_cmd, se_cmd->data_length, cmd->write_data_done);
2406 	wr->iser_ib_op = ISER_IB_RDMA_READ;
2407 	rc = device->reg_rdma_mem(conn, cmd, wr);
2408 	if (rc) {
2409 		pr_err("Cmd: %p failed to prepare RDMA res\n", isert_cmd);
2410 		return rc;
2411 	}
2412 
2413 	atomic_inc(&isert_conn->post_send_buf_count);
2414 
2415 	rc = ib_post_send(isert_conn->conn_qp, wr->send_wr, &wr_failed);
2416 	if (rc) {
2417 		pr_warn("ib_post_send() failed for IB_WR_RDMA_READ\n");
2418 		atomic_dec(&isert_conn->post_send_buf_count);
2419 	}
2420 	pr_debug("Cmd: %p posted RDMA_READ memory for ISER Data WRITE\n",
2421 		 isert_cmd);
2422 
2423 	return 0;
2424 }
2425 
2426 static int
2427 isert_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2428 {
2429 	int ret;
2430 
2431 	switch (state) {
2432 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
2433 		ret = isert_put_nopin(cmd, conn, false);
2434 		break;
2435 	default:
2436 		pr_err("Unknown immediate state: 0x%02x\n", state);
2437 		ret = -EINVAL;
2438 		break;
2439 	}
2440 
2441 	return ret;
2442 }
2443 
2444 static int
2445 isert_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
2446 {
2447 	int ret;
2448 
2449 	switch (state) {
2450 	case ISTATE_SEND_LOGOUTRSP:
2451 		ret = isert_put_logout_rsp(cmd, conn);
2452 		if (!ret) {
2453 			pr_debug("Returning iSER Logout -EAGAIN\n");
2454 			ret = -EAGAIN;
2455 		}
2456 		break;
2457 	case ISTATE_SEND_NOPIN:
2458 		ret = isert_put_nopin(cmd, conn, true);
2459 		break;
2460 	case ISTATE_SEND_TASKMGTRSP:
2461 		ret = isert_put_tm_rsp(cmd, conn);
2462 		break;
2463 	case ISTATE_SEND_REJECT:
2464 		ret = isert_put_reject(cmd, conn);
2465 		break;
2466 	case ISTATE_SEND_TEXTRSP:
2467 		ret = isert_put_text_rsp(cmd, conn);
2468 		break;
2469 	case ISTATE_SEND_STATUS:
2470 		/*
2471 		 * Special case for sending non GOOD SCSI status from TX thread
2472 		 * context during pre se_cmd excecution failure.
2473 		 */
2474 		ret = isert_put_response(conn, cmd);
2475 		break;
2476 	default:
2477 		pr_err("Unknown response state: 0x%02x\n", state);
2478 		ret = -EINVAL;
2479 		break;
2480 	}
2481 
2482 	return ret;
2483 }
2484 
2485 static int
2486 isert_setup_np(struct iscsi_np *np,
2487 	       struct __kernel_sockaddr_storage *ksockaddr)
2488 {
2489 	struct isert_np *isert_np;
2490 	struct rdma_cm_id *isert_lid;
2491 	struct sockaddr *sa;
2492 	int ret;
2493 
2494 	isert_np = kzalloc(sizeof(struct isert_np), GFP_KERNEL);
2495 	if (!isert_np) {
2496 		pr_err("Unable to allocate struct isert_np\n");
2497 		return -ENOMEM;
2498 	}
2499 	init_waitqueue_head(&isert_np->np_accept_wq);
2500 	mutex_init(&isert_np->np_accept_mutex);
2501 	INIT_LIST_HEAD(&isert_np->np_accept_list);
2502 	init_completion(&isert_np->np_login_comp);
2503 
2504 	sa = (struct sockaddr *)ksockaddr;
2505 	pr_debug("ksockaddr: %p, sa: %p\n", ksockaddr, sa);
2506 	/*
2507 	 * Setup the np->np_sockaddr from the passed sockaddr setup
2508 	 * in iscsi_target_configfs.c code..
2509 	 */
2510 	memcpy(&np->np_sockaddr, ksockaddr,
2511 	       sizeof(struct __kernel_sockaddr_storage));
2512 
2513 	isert_lid = rdma_create_id(isert_cma_handler, np, RDMA_PS_TCP,
2514 				IB_QPT_RC);
2515 	if (IS_ERR(isert_lid)) {
2516 		pr_err("rdma_create_id() for isert_listen_handler failed: %ld\n",
2517 		       PTR_ERR(isert_lid));
2518 		ret = PTR_ERR(isert_lid);
2519 		goto out;
2520 	}
2521 
2522 	ret = rdma_bind_addr(isert_lid, sa);
2523 	if (ret) {
2524 		pr_err("rdma_bind_addr() for isert_lid failed: %d\n", ret);
2525 		goto out_lid;
2526 	}
2527 
2528 	ret = rdma_listen(isert_lid, ISERT_RDMA_LISTEN_BACKLOG);
2529 	if (ret) {
2530 		pr_err("rdma_listen() for isert_lid failed: %d\n", ret);
2531 		goto out_lid;
2532 	}
2533 
2534 	isert_np->np_cm_id = isert_lid;
2535 	np->np_context = isert_np;
2536 	pr_debug("Setup isert_lid->context: %p\n", isert_lid->context);
2537 
2538 	return 0;
2539 
2540 out_lid:
2541 	rdma_destroy_id(isert_lid);
2542 out:
2543 	kfree(isert_np);
2544 	return ret;
2545 }
2546 
2547 static int
2548 isert_check_accept_queue(struct isert_np *isert_np)
2549 {
2550 	int empty;
2551 
2552 	mutex_lock(&isert_np->np_accept_mutex);
2553 	empty = list_empty(&isert_np->np_accept_list);
2554 	mutex_unlock(&isert_np->np_accept_mutex);
2555 
2556 	return empty;
2557 }
2558 
2559 static int
2560 isert_rdma_accept(struct isert_conn *isert_conn)
2561 {
2562 	struct rdma_cm_id *cm_id = isert_conn->conn_cm_id;
2563 	struct rdma_conn_param cp;
2564 	int ret;
2565 
2566 	memset(&cp, 0, sizeof(struct rdma_conn_param));
2567 	cp.responder_resources = isert_conn->responder_resources;
2568 	cp.initiator_depth = isert_conn->initiator_depth;
2569 	cp.retry_count = 7;
2570 	cp.rnr_retry_count = 7;
2571 
2572 	pr_debug("Before rdma_accept >>>>>>>>>>>>>>>>>>>>.\n");
2573 
2574 	ret = rdma_accept(cm_id, &cp);
2575 	if (ret) {
2576 		pr_err("rdma_accept() failed with: %d\n", ret);
2577 		return ret;
2578 	}
2579 
2580 	pr_debug("After rdma_accept >>>>>>>>>>>>>>>>>>>>>.\n");
2581 
2582 	return 0;
2583 }
2584 
2585 static int
2586 isert_get_login_rx(struct iscsi_conn *conn, struct iscsi_login *login)
2587 {
2588 	struct isert_conn *isert_conn = (struct isert_conn *)conn->context;
2589 	int ret;
2590 
2591 	pr_debug("isert_get_login_rx before conn_login_comp conn: %p\n", conn);
2592 	/*
2593 	 * For login requests after the first PDU, isert_rx_login_req() will
2594 	 * kick schedule_delayed_work(&conn->login_work) as the packet is
2595 	 * received, which turns this callback from iscsi_target_do_login_rx()
2596 	 * into a NOP.
2597 	 */
2598 	if (!login->first_request)
2599 		return 0;
2600 
2601 	ret = wait_for_completion_interruptible(&isert_conn->conn_login_comp);
2602 	if (ret)
2603 		return ret;
2604 
2605 	pr_debug("isert_get_login_rx processing login->req: %p\n", login->req);
2606 	return 0;
2607 }
2608 
2609 static void
2610 isert_set_conn_info(struct iscsi_np *np, struct iscsi_conn *conn,
2611 		    struct isert_conn *isert_conn)
2612 {
2613 	struct rdma_cm_id *cm_id = isert_conn->conn_cm_id;
2614 	struct rdma_route *cm_route = &cm_id->route;
2615 	struct sockaddr_in *sock_in;
2616 	struct sockaddr_in6 *sock_in6;
2617 
2618 	conn->login_family = np->np_sockaddr.ss_family;
2619 
2620 	if (np->np_sockaddr.ss_family == AF_INET6) {
2621 		sock_in6 = (struct sockaddr_in6 *)&cm_route->addr.dst_addr;
2622 		snprintf(conn->login_ip, sizeof(conn->login_ip), "%pI6c",
2623 			 &sock_in6->sin6_addr.in6_u);
2624 		conn->login_port = ntohs(sock_in6->sin6_port);
2625 
2626 		sock_in6 = (struct sockaddr_in6 *)&cm_route->addr.src_addr;
2627 		snprintf(conn->local_ip, sizeof(conn->local_ip), "%pI6c",
2628 			 &sock_in6->sin6_addr.in6_u);
2629 		conn->local_port = ntohs(sock_in6->sin6_port);
2630 	} else {
2631 		sock_in = (struct sockaddr_in *)&cm_route->addr.dst_addr;
2632 		sprintf(conn->login_ip, "%pI4",
2633 			&sock_in->sin_addr.s_addr);
2634 		conn->login_port = ntohs(sock_in->sin_port);
2635 
2636 		sock_in = (struct sockaddr_in *)&cm_route->addr.src_addr;
2637 		sprintf(conn->local_ip, "%pI4",
2638 			&sock_in->sin_addr.s_addr);
2639 		conn->local_port = ntohs(sock_in->sin_port);
2640 	}
2641 }
2642 
2643 static int
2644 isert_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
2645 {
2646 	struct isert_np *isert_np = (struct isert_np *)np->np_context;
2647 	struct isert_conn *isert_conn;
2648 	int max_accept = 0, ret;
2649 
2650 accept_wait:
2651 	ret = wait_event_interruptible(isert_np->np_accept_wq,
2652 			!isert_check_accept_queue(isert_np) ||
2653 			np->np_thread_state == ISCSI_NP_THREAD_RESET);
2654 	if (max_accept > 5)
2655 		return -ENODEV;
2656 
2657 	spin_lock_bh(&np->np_thread_lock);
2658 	if (np->np_thread_state == ISCSI_NP_THREAD_RESET) {
2659 		spin_unlock_bh(&np->np_thread_lock);
2660 		pr_err("ISCSI_NP_THREAD_RESET for isert_accept_np\n");
2661 		return -ENODEV;
2662 	}
2663 	spin_unlock_bh(&np->np_thread_lock);
2664 
2665 	mutex_lock(&isert_np->np_accept_mutex);
2666 	if (list_empty(&isert_np->np_accept_list)) {
2667 		mutex_unlock(&isert_np->np_accept_mutex);
2668 		max_accept++;
2669 		goto accept_wait;
2670 	}
2671 	isert_conn = list_first_entry(&isert_np->np_accept_list,
2672 			struct isert_conn, conn_accept_node);
2673 	list_del_init(&isert_conn->conn_accept_node);
2674 	mutex_unlock(&isert_np->np_accept_mutex);
2675 
2676 	conn->context = isert_conn;
2677 	isert_conn->conn = conn;
2678 	max_accept = 0;
2679 
2680 	ret = isert_rdma_post_recvl(isert_conn);
2681 	if (ret)
2682 		return ret;
2683 
2684 	ret = isert_rdma_accept(isert_conn);
2685 	if (ret)
2686 		return ret;
2687 
2688 	isert_set_conn_info(np, conn, isert_conn);
2689 
2690 	pr_debug("Processing isert_accept_np: isert_conn: %p\n", isert_conn);
2691 	return 0;
2692 }
2693 
2694 static void
2695 isert_free_np(struct iscsi_np *np)
2696 {
2697 	struct isert_np *isert_np = (struct isert_np *)np->np_context;
2698 
2699 	rdma_destroy_id(isert_np->np_cm_id);
2700 
2701 	np->np_context = NULL;
2702 	kfree(isert_np);
2703 }
2704 
2705 static int isert_check_state(struct isert_conn *isert_conn, int state)
2706 {
2707 	int ret;
2708 
2709 	mutex_lock(&isert_conn->conn_mutex);
2710 	ret = (isert_conn->state == state);
2711 	mutex_unlock(&isert_conn->conn_mutex);
2712 
2713 	return ret;
2714 }
2715 
2716 static void isert_free_conn(struct iscsi_conn *conn)
2717 {
2718 	struct isert_conn *isert_conn = conn->context;
2719 
2720 	pr_debug("isert_free_conn: Starting \n");
2721 	/*
2722 	 * Decrement post_send_buf_count for special case when called
2723 	 * from isert_do_control_comp() -> iscsit_logout_post_handler()
2724 	 */
2725 	mutex_lock(&isert_conn->conn_mutex);
2726 	if (isert_conn->logout_posted)
2727 		atomic_dec(&isert_conn->post_send_buf_count);
2728 
2729 	if (isert_conn->conn_cm_id && isert_conn->state != ISER_CONN_DOWN) {
2730 		pr_debug("Calling rdma_disconnect from isert_free_conn\n");
2731 		rdma_disconnect(isert_conn->conn_cm_id);
2732 	}
2733 	/*
2734 	 * Only wait for conn_wait_comp_err if the isert_conn made it
2735 	 * into full feature phase..
2736 	 */
2737 	if (isert_conn->state == ISER_CONN_UP) {
2738 		pr_debug("isert_free_conn: Before wait_event comp_err %d\n",
2739 			 isert_conn->state);
2740 		mutex_unlock(&isert_conn->conn_mutex);
2741 
2742 		wait_event(isert_conn->conn_wait_comp_err,
2743 			  (isert_check_state(isert_conn, ISER_CONN_TERMINATING)));
2744 
2745 		wait_event(isert_conn->conn_wait,
2746 			  (isert_check_state(isert_conn, ISER_CONN_DOWN)));
2747 
2748 		isert_put_conn(isert_conn);
2749 		return;
2750 	}
2751 	if (isert_conn->state == ISER_CONN_INIT) {
2752 		mutex_unlock(&isert_conn->conn_mutex);
2753 		isert_put_conn(isert_conn);
2754 		return;
2755 	}
2756 	pr_debug("isert_free_conn: wait_event conn_wait %d\n",
2757 		 isert_conn->state);
2758 	mutex_unlock(&isert_conn->conn_mutex);
2759 
2760 	wait_event(isert_conn->conn_wait,
2761 		  (isert_check_state(isert_conn, ISER_CONN_DOWN)));
2762 
2763 	isert_put_conn(isert_conn);
2764 }
2765 
2766 static struct iscsit_transport iser_target_transport = {
2767 	.name			= "IB/iSER",
2768 	.transport_type		= ISCSI_INFINIBAND,
2769 	.priv_size		= sizeof(struct isert_cmd),
2770 	.owner			= THIS_MODULE,
2771 	.iscsit_setup_np	= isert_setup_np,
2772 	.iscsit_accept_np	= isert_accept_np,
2773 	.iscsit_free_np		= isert_free_np,
2774 	.iscsit_free_conn	= isert_free_conn,
2775 	.iscsit_get_login_rx	= isert_get_login_rx,
2776 	.iscsit_put_login_tx	= isert_put_login_tx,
2777 	.iscsit_immediate_queue	= isert_immediate_queue,
2778 	.iscsit_response_queue	= isert_response_queue,
2779 	.iscsit_get_dataout	= isert_get_dataout,
2780 	.iscsit_queue_data_in	= isert_put_datain,
2781 	.iscsit_queue_status	= isert_put_response,
2782 };
2783 
2784 static int __init isert_init(void)
2785 {
2786 	int ret;
2787 
2788 	isert_rx_wq = alloc_workqueue("isert_rx_wq", 0, 0);
2789 	if (!isert_rx_wq) {
2790 		pr_err("Unable to allocate isert_rx_wq\n");
2791 		return -ENOMEM;
2792 	}
2793 
2794 	isert_comp_wq = alloc_workqueue("isert_comp_wq", 0, 0);
2795 	if (!isert_comp_wq) {
2796 		pr_err("Unable to allocate isert_comp_wq\n");
2797 		ret = -ENOMEM;
2798 		goto destroy_rx_wq;
2799 	}
2800 
2801 	iscsit_register_transport(&iser_target_transport);
2802 	pr_debug("iSER_TARGET[0] - Loaded iser_target_transport\n");
2803 	return 0;
2804 
2805 destroy_rx_wq:
2806 	destroy_workqueue(isert_rx_wq);
2807 	return ret;
2808 }
2809 
2810 static void __exit isert_exit(void)
2811 {
2812 	destroy_workqueue(isert_comp_wq);
2813 	destroy_workqueue(isert_rx_wq);
2814 	iscsit_unregister_transport(&iser_target_transport);
2815 	pr_debug("iSER_TARGET[0] - Released iser_target_transport\n");
2816 }
2817 
2818 MODULE_DESCRIPTION("iSER-Target for mainline target infrastructure");
2819 MODULE_VERSION("0.1");
2820 MODULE_AUTHOR("nab@Linux-iSCSI.org");
2821 MODULE_LICENSE("GPL");
2822 
2823 module_init(isert_init);
2824 module_exit(isert_exit);
2825