xref: /linux/drivers/infiniband/ulp/isert/ib_isert.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
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 <rdma/ib_verbs.h>
26 #include <rdma/rdma_cm.h>
27 #include <target/target_core_base.h>
28 #include <target/target_core_fabric.h>
29 #include <target/iscsi/iscsi_transport.h>
30 #include <linux/semaphore.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 #define ISER_MAX_CQ_LEN		(ISER_MAX_RX_CQ_LEN + ISER_MAX_TX_CQ_LEN + \
39 				 ISERT_MAX_CONN)
40 
41 static int isert_debug_level;
42 module_param_named(debug_level, isert_debug_level, int, 0644);
43 MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:0)");
44 
45 static DEFINE_MUTEX(device_list_mutex);
46 static LIST_HEAD(device_list);
47 static struct workqueue_struct *isert_comp_wq;
48 static struct workqueue_struct *isert_release_wq;
49 
50 static void
51 isert_unmap_cmd(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn);
52 static int
53 isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
54 	       struct isert_rdma_wr *wr);
55 static void
56 isert_unreg_rdma(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn);
57 static int
58 isert_reg_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
59 	       struct isert_rdma_wr *wr);
60 static int
61 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd);
62 static int
63 isert_rdma_post_recvl(struct isert_conn *isert_conn);
64 static int
65 isert_rdma_accept(struct isert_conn *isert_conn);
66 struct rdma_cm_id *isert_setup_id(struct isert_np *isert_np);
67 
68 static void isert_release_work(struct work_struct *work);
69 
70 static inline bool
71 isert_prot_cmd(struct isert_conn *conn, struct se_cmd *cmd)
72 {
73 	return (conn->pi_support &&
74 		cmd->prot_op != TARGET_PROT_NORMAL);
75 }
76 
77 
78 static void
79 isert_qp_event_callback(struct ib_event *e, void *context)
80 {
81 	struct isert_conn *isert_conn = context;
82 
83 	isert_err("%s (%d): conn %p\n",
84 		  ib_event_msg(e->event), e->event, isert_conn);
85 
86 	switch (e->event) {
87 	case IB_EVENT_COMM_EST:
88 		rdma_notify(isert_conn->cm_id, IB_EVENT_COMM_EST);
89 		break;
90 	case IB_EVENT_QP_LAST_WQE_REACHED:
91 		isert_warn("Reached TX IB_EVENT_QP_LAST_WQE_REACHED\n");
92 		break;
93 	default:
94 		break;
95 	}
96 }
97 
98 static int
99 isert_query_device(struct ib_device *ib_dev, struct ib_device_attr *devattr)
100 {
101 	int ret;
102 
103 	ret = ib_query_device(ib_dev, devattr);
104 	if (ret) {
105 		isert_err("ib_query_device() failed: %d\n", ret);
106 		return ret;
107 	}
108 	isert_dbg("devattr->max_sge: %d\n", devattr->max_sge);
109 	isert_dbg("devattr->max_sge_rd: %d\n", devattr->max_sge_rd);
110 
111 	return 0;
112 }
113 
114 static struct isert_comp *
115 isert_comp_get(struct isert_conn *isert_conn)
116 {
117 	struct isert_device *device = isert_conn->device;
118 	struct isert_comp *comp;
119 	int i, min = 0;
120 
121 	mutex_lock(&device_list_mutex);
122 	for (i = 0; i < device->comps_used; i++)
123 		if (device->comps[i].active_qps <
124 		    device->comps[min].active_qps)
125 			min = i;
126 	comp = &device->comps[min];
127 	comp->active_qps++;
128 	mutex_unlock(&device_list_mutex);
129 
130 	isert_info("conn %p, using comp %p min_index: %d\n",
131 		   isert_conn, comp, min);
132 
133 	return comp;
134 }
135 
136 static void
137 isert_comp_put(struct isert_comp *comp)
138 {
139 	mutex_lock(&device_list_mutex);
140 	comp->active_qps--;
141 	mutex_unlock(&device_list_mutex);
142 }
143 
144 static struct ib_qp *
145 isert_create_qp(struct isert_conn *isert_conn,
146 		struct isert_comp *comp,
147 		struct rdma_cm_id *cma_id)
148 {
149 	struct isert_device *device = isert_conn->device;
150 	struct ib_qp_init_attr attr;
151 	int ret;
152 
153 	memset(&attr, 0, sizeof(struct ib_qp_init_attr));
154 	attr.event_handler = isert_qp_event_callback;
155 	attr.qp_context = isert_conn;
156 	attr.send_cq = comp->cq;
157 	attr.recv_cq = comp->cq;
158 	attr.cap.max_send_wr = ISERT_QP_MAX_REQ_DTOS;
159 	attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS + 1;
160 	/*
161 	 * FIXME: Use devattr.max_sge - 2 for max_send_sge as
162 	 * work-around for RDMA_READs with ConnectX-2.
163 	 *
164 	 * Also, still make sure to have at least two SGEs for
165 	 * outgoing control PDU responses.
166 	 */
167 	attr.cap.max_send_sge = max(2, device->dev_attr.max_sge - 2);
168 	isert_conn->max_sge = attr.cap.max_send_sge;
169 
170 	attr.cap.max_recv_sge = 1;
171 	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
172 	attr.qp_type = IB_QPT_RC;
173 	if (device->pi_capable)
174 		attr.create_flags |= IB_QP_CREATE_SIGNATURE_EN;
175 
176 	ret = rdma_create_qp(cma_id, device->pd, &attr);
177 	if (ret) {
178 		isert_err("rdma_create_qp failed for cma_id %d\n", ret);
179 		return ERR_PTR(ret);
180 	}
181 
182 	return cma_id->qp;
183 }
184 
185 static int
186 isert_conn_setup_qp(struct isert_conn *isert_conn, struct rdma_cm_id *cma_id)
187 {
188 	struct isert_comp *comp;
189 	int ret;
190 
191 	comp = isert_comp_get(isert_conn);
192 	isert_conn->qp = isert_create_qp(isert_conn, comp, cma_id);
193 	if (IS_ERR(isert_conn->qp)) {
194 		ret = PTR_ERR(isert_conn->qp);
195 		goto err;
196 	}
197 
198 	return 0;
199 err:
200 	isert_comp_put(comp);
201 	return ret;
202 }
203 
204 static void
205 isert_cq_event_callback(struct ib_event *e, void *context)
206 {
207 	isert_dbg("event: %d\n", e->event);
208 }
209 
210 static int
211 isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
212 {
213 	struct isert_device *device = isert_conn->device;
214 	struct ib_device *ib_dev = device->ib_device;
215 	struct iser_rx_desc *rx_desc;
216 	struct ib_sge *rx_sg;
217 	u64 dma_addr;
218 	int i, j;
219 
220 	isert_conn->rx_descs = kzalloc(ISERT_QP_MAX_RECV_DTOS *
221 				sizeof(struct iser_rx_desc), GFP_KERNEL);
222 	if (!isert_conn->rx_descs)
223 		goto fail;
224 
225 	rx_desc = isert_conn->rx_descs;
226 
227 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
228 		dma_addr = ib_dma_map_single(ib_dev, (void *)rx_desc,
229 					ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
230 		if (ib_dma_mapping_error(ib_dev, dma_addr))
231 			goto dma_map_fail;
232 
233 		rx_desc->dma_addr = dma_addr;
234 
235 		rx_sg = &rx_desc->rx_sg;
236 		rx_sg->addr = rx_desc->dma_addr;
237 		rx_sg->length = ISER_RX_PAYLOAD_SIZE;
238 		rx_sg->lkey = device->pd->local_dma_lkey;
239 	}
240 
241 	return 0;
242 
243 dma_map_fail:
244 	rx_desc = isert_conn->rx_descs;
245 	for (j = 0; j < i; j++, rx_desc++) {
246 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
247 				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
248 	}
249 	kfree(isert_conn->rx_descs);
250 	isert_conn->rx_descs = NULL;
251 fail:
252 	isert_err("conn %p failed to allocate rx descriptors\n", isert_conn);
253 
254 	return -ENOMEM;
255 }
256 
257 static void
258 isert_free_rx_descriptors(struct isert_conn *isert_conn)
259 {
260 	struct ib_device *ib_dev = isert_conn->device->ib_device;
261 	struct iser_rx_desc *rx_desc;
262 	int i;
263 
264 	if (!isert_conn->rx_descs)
265 		return;
266 
267 	rx_desc = isert_conn->rx_descs;
268 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
269 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
270 				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
271 	}
272 
273 	kfree(isert_conn->rx_descs);
274 	isert_conn->rx_descs = NULL;
275 }
276 
277 static void isert_cq_work(struct work_struct *);
278 static void isert_cq_callback(struct ib_cq *, void *);
279 
280 static void
281 isert_free_comps(struct isert_device *device)
282 {
283 	int i;
284 
285 	for (i = 0; i < device->comps_used; i++) {
286 		struct isert_comp *comp = &device->comps[i];
287 
288 		if (comp->cq) {
289 			cancel_work_sync(&comp->work);
290 			ib_destroy_cq(comp->cq);
291 		}
292 	}
293 	kfree(device->comps);
294 }
295 
296 static int
297 isert_alloc_comps(struct isert_device *device,
298 		  struct ib_device_attr *attr)
299 {
300 	int i, max_cqe, ret = 0;
301 
302 	device->comps_used = min(ISERT_MAX_CQ, min_t(int, num_online_cpus(),
303 				 device->ib_device->num_comp_vectors));
304 
305 	isert_info("Using %d CQs, %s supports %d vectors support "
306 		   "Fast registration %d pi_capable %d\n",
307 		   device->comps_used, device->ib_device->name,
308 		   device->ib_device->num_comp_vectors, device->use_fastreg,
309 		   device->pi_capable);
310 
311 	device->comps = kcalloc(device->comps_used, sizeof(struct isert_comp),
312 				GFP_KERNEL);
313 	if (!device->comps) {
314 		isert_err("Unable to allocate completion contexts\n");
315 		return -ENOMEM;
316 	}
317 
318 	max_cqe = min(ISER_MAX_CQ_LEN, attr->max_cqe);
319 
320 	for (i = 0; i < device->comps_used; i++) {
321 		struct ib_cq_init_attr cq_attr = {};
322 		struct isert_comp *comp = &device->comps[i];
323 
324 		comp->device = device;
325 		INIT_WORK(&comp->work, isert_cq_work);
326 		cq_attr.cqe = max_cqe;
327 		cq_attr.comp_vector = i;
328 		comp->cq = ib_create_cq(device->ib_device,
329 					isert_cq_callback,
330 					isert_cq_event_callback,
331 					(void *)comp,
332 					&cq_attr);
333 		if (IS_ERR(comp->cq)) {
334 			isert_err("Unable to allocate cq\n");
335 			ret = PTR_ERR(comp->cq);
336 			comp->cq = NULL;
337 			goto out_cq;
338 		}
339 
340 		ret = ib_req_notify_cq(comp->cq, IB_CQ_NEXT_COMP);
341 		if (ret)
342 			goto out_cq;
343 	}
344 
345 	return 0;
346 out_cq:
347 	isert_free_comps(device);
348 	return ret;
349 }
350 
351 static int
352 isert_create_device_ib_res(struct isert_device *device)
353 {
354 	struct ib_device_attr *dev_attr;
355 	int ret;
356 
357 	dev_attr = &device->dev_attr;
358 	ret = isert_query_device(device->ib_device, dev_attr);
359 	if (ret)
360 		return ret;
361 
362 	/* asign function handlers */
363 	if (dev_attr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS &&
364 	    dev_attr->device_cap_flags & IB_DEVICE_SIGNATURE_HANDOVER) {
365 		device->use_fastreg = 1;
366 		device->reg_rdma_mem = isert_reg_rdma;
367 		device->unreg_rdma_mem = isert_unreg_rdma;
368 	} else {
369 		device->use_fastreg = 0;
370 		device->reg_rdma_mem = isert_map_rdma;
371 		device->unreg_rdma_mem = isert_unmap_cmd;
372 	}
373 
374 	ret = isert_alloc_comps(device, dev_attr);
375 	if (ret)
376 		return ret;
377 
378 	device->pd = ib_alloc_pd(device->ib_device);
379 	if (IS_ERR(device->pd)) {
380 		ret = PTR_ERR(device->pd);
381 		isert_err("failed to allocate pd, device %p, ret=%d\n",
382 			  device, ret);
383 		goto out_cq;
384 	}
385 
386 	/* Check signature cap */
387 	device->pi_capable = dev_attr->device_cap_flags &
388 			     IB_DEVICE_SIGNATURE_HANDOVER ? true : false;
389 
390 	return 0;
391 
392 out_cq:
393 	isert_free_comps(device);
394 	return ret;
395 }
396 
397 static void
398 isert_free_device_ib_res(struct isert_device *device)
399 {
400 	isert_info("device %p\n", device);
401 
402 	ib_dealloc_pd(device->pd);
403 	isert_free_comps(device);
404 }
405 
406 static void
407 isert_device_put(struct isert_device *device)
408 {
409 	mutex_lock(&device_list_mutex);
410 	device->refcount--;
411 	isert_info("device %p refcount %d\n", device, device->refcount);
412 	if (!device->refcount) {
413 		isert_free_device_ib_res(device);
414 		list_del(&device->dev_node);
415 		kfree(device);
416 	}
417 	mutex_unlock(&device_list_mutex);
418 }
419 
420 static struct isert_device *
421 isert_device_get(struct rdma_cm_id *cma_id)
422 {
423 	struct isert_device *device;
424 	int ret;
425 
426 	mutex_lock(&device_list_mutex);
427 	list_for_each_entry(device, &device_list, dev_node) {
428 		if (device->ib_device->node_guid == cma_id->device->node_guid) {
429 			device->refcount++;
430 			isert_info("Found iser device %p refcount %d\n",
431 				   device, device->refcount);
432 			mutex_unlock(&device_list_mutex);
433 			return device;
434 		}
435 	}
436 
437 	device = kzalloc(sizeof(struct isert_device), GFP_KERNEL);
438 	if (!device) {
439 		mutex_unlock(&device_list_mutex);
440 		return ERR_PTR(-ENOMEM);
441 	}
442 
443 	INIT_LIST_HEAD(&device->dev_node);
444 
445 	device->ib_device = cma_id->device;
446 	ret = isert_create_device_ib_res(device);
447 	if (ret) {
448 		kfree(device);
449 		mutex_unlock(&device_list_mutex);
450 		return ERR_PTR(ret);
451 	}
452 
453 	device->refcount++;
454 	list_add_tail(&device->dev_node, &device_list);
455 	isert_info("Created a new iser device %p refcount %d\n",
456 		   device, device->refcount);
457 	mutex_unlock(&device_list_mutex);
458 
459 	return device;
460 }
461 
462 static void
463 isert_conn_free_fastreg_pool(struct isert_conn *isert_conn)
464 {
465 	struct fast_reg_descriptor *fr_desc, *tmp;
466 	int i = 0;
467 
468 	if (list_empty(&isert_conn->fr_pool))
469 		return;
470 
471 	isert_info("Freeing conn %p fastreg pool", isert_conn);
472 
473 	list_for_each_entry_safe(fr_desc, tmp,
474 				 &isert_conn->fr_pool, list) {
475 		list_del(&fr_desc->list);
476 		ib_free_fast_reg_page_list(fr_desc->data_frpl);
477 		ib_dereg_mr(fr_desc->data_mr);
478 		if (fr_desc->pi_ctx) {
479 			ib_free_fast_reg_page_list(fr_desc->pi_ctx->prot_frpl);
480 			ib_dereg_mr(fr_desc->pi_ctx->prot_mr);
481 			ib_dereg_mr(fr_desc->pi_ctx->sig_mr);
482 			kfree(fr_desc->pi_ctx);
483 		}
484 		kfree(fr_desc);
485 		++i;
486 	}
487 
488 	if (i < isert_conn->fr_pool_size)
489 		isert_warn("Pool still has %d regions registered\n",
490 			isert_conn->fr_pool_size - i);
491 }
492 
493 static int
494 isert_create_pi_ctx(struct fast_reg_descriptor *desc,
495 		    struct ib_device *device,
496 		    struct ib_pd *pd)
497 {
498 	struct pi_context *pi_ctx;
499 	int ret;
500 
501 	pi_ctx = kzalloc(sizeof(*desc->pi_ctx), GFP_KERNEL);
502 	if (!pi_ctx) {
503 		isert_err("Failed to allocate pi context\n");
504 		return -ENOMEM;
505 	}
506 
507 	pi_ctx->prot_frpl = ib_alloc_fast_reg_page_list(device,
508 					    ISCSI_ISER_SG_TABLESIZE);
509 	if (IS_ERR(pi_ctx->prot_frpl)) {
510 		isert_err("Failed to allocate prot frpl err=%ld\n",
511 			  PTR_ERR(pi_ctx->prot_frpl));
512 		ret = PTR_ERR(pi_ctx->prot_frpl);
513 		goto err_pi_ctx;
514 	}
515 
516 	pi_ctx->prot_mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG,
517 				      ISCSI_ISER_SG_TABLESIZE);
518 	if (IS_ERR(pi_ctx->prot_mr)) {
519 		isert_err("Failed to allocate prot frmr err=%ld\n",
520 			  PTR_ERR(pi_ctx->prot_mr));
521 		ret = PTR_ERR(pi_ctx->prot_mr);
522 		goto err_prot_frpl;
523 	}
524 	desc->ind |= ISERT_PROT_KEY_VALID;
525 
526 	pi_ctx->sig_mr = ib_alloc_mr(pd, IB_MR_TYPE_SIGNATURE, 2);
527 	if (IS_ERR(pi_ctx->sig_mr)) {
528 		isert_err("Failed to allocate signature enabled mr err=%ld\n",
529 			  PTR_ERR(pi_ctx->sig_mr));
530 		ret = PTR_ERR(pi_ctx->sig_mr);
531 		goto err_prot_mr;
532 	}
533 
534 	desc->pi_ctx = pi_ctx;
535 	desc->ind |= ISERT_SIG_KEY_VALID;
536 	desc->ind &= ~ISERT_PROTECTED;
537 
538 	return 0;
539 
540 err_prot_mr:
541 	ib_dereg_mr(pi_ctx->prot_mr);
542 err_prot_frpl:
543 	ib_free_fast_reg_page_list(pi_ctx->prot_frpl);
544 err_pi_ctx:
545 	kfree(pi_ctx);
546 
547 	return ret;
548 }
549 
550 static int
551 isert_create_fr_desc(struct ib_device *ib_device, struct ib_pd *pd,
552 		     struct fast_reg_descriptor *fr_desc)
553 {
554 	int ret;
555 
556 	fr_desc->data_frpl = ib_alloc_fast_reg_page_list(ib_device,
557 							 ISCSI_ISER_SG_TABLESIZE);
558 	if (IS_ERR(fr_desc->data_frpl)) {
559 		isert_err("Failed to allocate data frpl err=%ld\n",
560 			  PTR_ERR(fr_desc->data_frpl));
561 		return PTR_ERR(fr_desc->data_frpl);
562 	}
563 
564 	fr_desc->data_mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG,
565 				       ISCSI_ISER_SG_TABLESIZE);
566 	if (IS_ERR(fr_desc->data_mr)) {
567 		isert_err("Failed to allocate data frmr err=%ld\n",
568 			  PTR_ERR(fr_desc->data_mr));
569 		ret = PTR_ERR(fr_desc->data_mr);
570 		goto err_data_frpl;
571 	}
572 	fr_desc->ind |= ISERT_DATA_KEY_VALID;
573 
574 	isert_dbg("Created fr_desc %p\n", fr_desc);
575 
576 	return 0;
577 
578 err_data_frpl:
579 	ib_free_fast_reg_page_list(fr_desc->data_frpl);
580 
581 	return ret;
582 }
583 
584 static int
585 isert_conn_create_fastreg_pool(struct isert_conn *isert_conn)
586 {
587 	struct fast_reg_descriptor *fr_desc;
588 	struct isert_device *device = isert_conn->device;
589 	struct se_session *se_sess = isert_conn->conn->sess->se_sess;
590 	struct se_node_acl *se_nacl = se_sess->se_node_acl;
591 	int i, ret, tag_num;
592 	/*
593 	 * Setup the number of FRMRs based upon the number of tags
594 	 * available to session in iscsi_target_locate_portal().
595 	 */
596 	tag_num = max_t(u32, ISCSIT_MIN_TAGS, se_nacl->queue_depth);
597 	tag_num = (tag_num * 2) + ISCSIT_EXTRA_TAGS;
598 
599 	isert_conn->fr_pool_size = 0;
600 	for (i = 0; i < tag_num; i++) {
601 		fr_desc = kzalloc(sizeof(*fr_desc), GFP_KERNEL);
602 		if (!fr_desc) {
603 			isert_err("Failed to allocate fast_reg descriptor\n");
604 			ret = -ENOMEM;
605 			goto err;
606 		}
607 
608 		ret = isert_create_fr_desc(device->ib_device,
609 					   device->pd, fr_desc);
610 		if (ret) {
611 			isert_err("Failed to create fastreg descriptor err=%d\n",
612 			       ret);
613 			kfree(fr_desc);
614 			goto err;
615 		}
616 
617 		list_add_tail(&fr_desc->list, &isert_conn->fr_pool);
618 		isert_conn->fr_pool_size++;
619 	}
620 
621 	isert_dbg("Creating conn %p fastreg pool size=%d",
622 		 isert_conn, isert_conn->fr_pool_size);
623 
624 	return 0;
625 
626 err:
627 	isert_conn_free_fastreg_pool(isert_conn);
628 	return ret;
629 }
630 
631 static void
632 isert_init_conn(struct isert_conn *isert_conn)
633 {
634 	isert_conn->state = ISER_CONN_INIT;
635 	INIT_LIST_HEAD(&isert_conn->node);
636 	init_completion(&isert_conn->login_comp);
637 	init_completion(&isert_conn->login_req_comp);
638 	init_completion(&isert_conn->wait);
639 	kref_init(&isert_conn->kref);
640 	mutex_init(&isert_conn->mutex);
641 	spin_lock_init(&isert_conn->pool_lock);
642 	INIT_LIST_HEAD(&isert_conn->fr_pool);
643 	INIT_WORK(&isert_conn->release_work, isert_release_work);
644 }
645 
646 static void
647 isert_free_login_buf(struct isert_conn *isert_conn)
648 {
649 	struct ib_device *ib_dev = isert_conn->device->ib_device;
650 
651 	ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
652 			    ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
653 	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
654 			    ISCSI_DEF_MAX_RECV_SEG_LEN,
655 			    DMA_FROM_DEVICE);
656 	kfree(isert_conn->login_buf);
657 }
658 
659 static int
660 isert_alloc_login_buf(struct isert_conn *isert_conn,
661 		      struct ib_device *ib_dev)
662 {
663 	int ret;
664 
665 	isert_conn->login_buf = kzalloc(ISCSI_DEF_MAX_RECV_SEG_LEN +
666 					ISER_RX_LOGIN_SIZE, GFP_KERNEL);
667 	if (!isert_conn->login_buf) {
668 		isert_err("Unable to allocate isert_conn->login_buf\n");
669 		return -ENOMEM;
670 	}
671 
672 	isert_conn->login_req_buf = isert_conn->login_buf;
673 	isert_conn->login_rsp_buf = isert_conn->login_buf +
674 				    ISCSI_DEF_MAX_RECV_SEG_LEN;
675 
676 	isert_dbg("Set login_buf: %p login_req_buf: %p login_rsp_buf: %p\n",
677 		 isert_conn->login_buf, isert_conn->login_req_buf,
678 		 isert_conn->login_rsp_buf);
679 
680 	isert_conn->login_req_dma = ib_dma_map_single(ib_dev,
681 				(void *)isert_conn->login_req_buf,
682 				ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
683 
684 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_req_dma);
685 	if (ret) {
686 		isert_err("login_req_dma mapping error: %d\n", ret);
687 		isert_conn->login_req_dma = 0;
688 		goto out_login_buf;
689 	}
690 
691 	isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
692 					(void *)isert_conn->login_rsp_buf,
693 					ISER_RX_LOGIN_SIZE, DMA_TO_DEVICE);
694 
695 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
696 	if (ret) {
697 		isert_err("login_rsp_dma mapping error: %d\n", ret);
698 		isert_conn->login_rsp_dma = 0;
699 		goto out_req_dma_map;
700 	}
701 
702 	return 0;
703 
704 out_req_dma_map:
705 	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
706 			    ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_FROM_DEVICE);
707 out_login_buf:
708 	kfree(isert_conn->login_buf);
709 	return ret;
710 }
711 
712 static int
713 isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
714 {
715 	struct isert_np *isert_np = cma_id->context;
716 	struct iscsi_np *np = isert_np->np;
717 	struct isert_conn *isert_conn;
718 	struct isert_device *device;
719 	int ret = 0;
720 
721 	spin_lock_bh(&np->np_thread_lock);
722 	if (!np->enabled) {
723 		spin_unlock_bh(&np->np_thread_lock);
724 		isert_dbg("iscsi_np is not enabled, reject connect request\n");
725 		return rdma_reject(cma_id, NULL, 0);
726 	}
727 	spin_unlock_bh(&np->np_thread_lock);
728 
729 	isert_dbg("cma_id: %p, portal: %p\n",
730 		 cma_id, cma_id->context);
731 
732 	isert_conn = kzalloc(sizeof(struct isert_conn), GFP_KERNEL);
733 	if (!isert_conn)
734 		return -ENOMEM;
735 
736 	isert_init_conn(isert_conn);
737 	isert_conn->cm_id = cma_id;
738 
739 	ret = isert_alloc_login_buf(isert_conn, cma_id->device);
740 	if (ret)
741 		goto out;
742 
743 	device = isert_device_get(cma_id);
744 	if (IS_ERR(device)) {
745 		ret = PTR_ERR(device);
746 		goto out_rsp_dma_map;
747 	}
748 	isert_conn->device = device;
749 
750 	/* Set max inflight RDMA READ requests */
751 	isert_conn->initiator_depth = min_t(u8,
752 				event->param.conn.initiator_depth,
753 				device->dev_attr.max_qp_init_rd_atom);
754 	isert_dbg("Using initiator_depth: %u\n", isert_conn->initiator_depth);
755 
756 	ret = isert_conn_setup_qp(isert_conn, cma_id);
757 	if (ret)
758 		goto out_conn_dev;
759 
760 	ret = isert_rdma_post_recvl(isert_conn);
761 	if (ret)
762 		goto out_conn_dev;
763 
764 	ret = isert_rdma_accept(isert_conn);
765 	if (ret)
766 		goto out_conn_dev;
767 
768 	mutex_lock(&isert_np->mutex);
769 	list_add_tail(&isert_conn->node, &isert_np->accepted);
770 	mutex_unlock(&isert_np->mutex);
771 
772 	return 0;
773 
774 out_conn_dev:
775 	isert_device_put(device);
776 out_rsp_dma_map:
777 	isert_free_login_buf(isert_conn);
778 out:
779 	kfree(isert_conn);
780 	rdma_reject(cma_id, NULL, 0);
781 	return ret;
782 }
783 
784 static void
785 isert_connect_release(struct isert_conn *isert_conn)
786 {
787 	struct isert_device *device = isert_conn->device;
788 
789 	isert_dbg("conn %p\n", isert_conn);
790 
791 	BUG_ON(!device);
792 
793 	if (device->use_fastreg)
794 		isert_conn_free_fastreg_pool(isert_conn);
795 
796 	isert_free_rx_descriptors(isert_conn);
797 	if (isert_conn->cm_id)
798 		rdma_destroy_id(isert_conn->cm_id);
799 
800 	if (isert_conn->qp) {
801 		struct isert_comp *comp = isert_conn->qp->recv_cq->cq_context;
802 
803 		isert_comp_put(comp);
804 		ib_destroy_qp(isert_conn->qp);
805 	}
806 
807 	if (isert_conn->login_buf)
808 		isert_free_login_buf(isert_conn);
809 
810 	isert_device_put(device);
811 
812 	kfree(isert_conn);
813 }
814 
815 static void
816 isert_connected_handler(struct rdma_cm_id *cma_id)
817 {
818 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
819 	struct isert_np *isert_np = cma_id->context;
820 
821 	isert_info("conn %p\n", isert_conn);
822 
823 	mutex_lock(&isert_conn->mutex);
824 	isert_conn->state = ISER_CONN_UP;
825 	kref_get(&isert_conn->kref);
826 	mutex_unlock(&isert_conn->mutex);
827 
828 	mutex_lock(&isert_np->mutex);
829 	list_move_tail(&isert_conn->node, &isert_np->pending);
830 	mutex_unlock(&isert_np->mutex);
831 
832 	isert_info("np %p: Allow accept_np to continue\n", isert_np);
833 	up(&isert_np->sem);
834 }
835 
836 static void
837 isert_release_kref(struct kref *kref)
838 {
839 	struct isert_conn *isert_conn = container_of(kref,
840 				struct isert_conn, kref);
841 
842 	isert_info("conn %p final kref %s/%d\n", isert_conn, current->comm,
843 		   current->pid);
844 
845 	isert_connect_release(isert_conn);
846 }
847 
848 static void
849 isert_put_conn(struct isert_conn *isert_conn)
850 {
851 	kref_put(&isert_conn->kref, isert_release_kref);
852 }
853 
854 /**
855  * isert_conn_terminate() - Initiate connection termination
856  * @isert_conn: isert connection struct
857  *
858  * Notes:
859  * In case the connection state is FULL_FEATURE, move state
860  * to TEMINATING and start teardown sequence (rdma_disconnect).
861  * In case the connection state is UP, complete flush as well.
862  *
863  * This routine must be called with mutex held. Thus it is
864  * safe to call multiple times.
865  */
866 static void
867 isert_conn_terminate(struct isert_conn *isert_conn)
868 {
869 	int err;
870 
871 	switch (isert_conn->state) {
872 	case ISER_CONN_TERMINATING:
873 		break;
874 	case ISER_CONN_UP:
875 	case ISER_CONN_FULL_FEATURE: /* FALLTHRU */
876 		isert_info("Terminating conn %p state %d\n",
877 			   isert_conn, isert_conn->state);
878 		isert_conn->state = ISER_CONN_TERMINATING;
879 		err = rdma_disconnect(isert_conn->cm_id);
880 		if (err)
881 			isert_warn("Failed rdma_disconnect isert_conn %p\n",
882 				   isert_conn);
883 		break;
884 	default:
885 		isert_warn("conn %p teminating in state %d\n",
886 			   isert_conn, isert_conn->state);
887 	}
888 }
889 
890 static int
891 isert_np_cma_handler(struct isert_np *isert_np,
892 		     enum rdma_cm_event_type event)
893 {
894 	isert_dbg("%s (%d): isert np %p\n",
895 		  rdma_event_msg(event), event, isert_np);
896 
897 	switch (event) {
898 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
899 		isert_np->cm_id = NULL;
900 		break;
901 	case RDMA_CM_EVENT_ADDR_CHANGE:
902 		isert_np->cm_id = isert_setup_id(isert_np);
903 		if (IS_ERR(isert_np->cm_id)) {
904 			isert_err("isert np %p setup id failed: %ld\n",
905 				  isert_np, PTR_ERR(isert_np->cm_id));
906 			isert_np->cm_id = NULL;
907 		}
908 		break;
909 	default:
910 		isert_err("isert np %p Unexpected event %d\n",
911 			  isert_np, event);
912 	}
913 
914 	return -1;
915 }
916 
917 static int
918 isert_disconnected_handler(struct rdma_cm_id *cma_id,
919 			   enum rdma_cm_event_type event)
920 {
921 	struct isert_np *isert_np = cma_id->context;
922 	struct isert_conn *isert_conn;
923 	bool terminating = false;
924 
925 	if (isert_np->cm_id == cma_id)
926 		return isert_np_cma_handler(cma_id->context, event);
927 
928 	isert_conn = cma_id->qp->qp_context;
929 
930 	mutex_lock(&isert_conn->mutex);
931 	terminating = (isert_conn->state == ISER_CONN_TERMINATING);
932 	isert_conn_terminate(isert_conn);
933 	mutex_unlock(&isert_conn->mutex);
934 
935 	isert_info("conn %p completing wait\n", isert_conn);
936 	complete(&isert_conn->wait);
937 
938 	if (terminating)
939 		goto out;
940 
941 	mutex_lock(&isert_np->mutex);
942 	if (!list_empty(&isert_conn->node)) {
943 		list_del_init(&isert_conn->node);
944 		isert_put_conn(isert_conn);
945 		queue_work(isert_release_wq, &isert_conn->release_work);
946 	}
947 	mutex_unlock(&isert_np->mutex);
948 
949 out:
950 	return 0;
951 }
952 
953 static int
954 isert_connect_error(struct rdma_cm_id *cma_id)
955 {
956 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
957 
958 	list_del_init(&isert_conn->node);
959 	isert_conn->cm_id = NULL;
960 	isert_put_conn(isert_conn);
961 
962 	return -1;
963 }
964 
965 static int
966 isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
967 {
968 	int ret = 0;
969 
970 	isert_info("%s (%d): status %d id %p np %p\n",
971 		   rdma_event_msg(event->event), event->event,
972 		   event->status, cma_id, cma_id->context);
973 
974 	switch (event->event) {
975 	case RDMA_CM_EVENT_CONNECT_REQUEST:
976 		ret = isert_connect_request(cma_id, event);
977 		if (ret)
978 			isert_err("failed handle connect request %d\n", ret);
979 		break;
980 	case RDMA_CM_EVENT_ESTABLISHED:
981 		isert_connected_handler(cma_id);
982 		break;
983 	case RDMA_CM_EVENT_ADDR_CHANGE:    /* FALLTHRU */
984 	case RDMA_CM_EVENT_DISCONNECTED:   /* FALLTHRU */
985 	case RDMA_CM_EVENT_DEVICE_REMOVAL: /* FALLTHRU */
986 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:  /* FALLTHRU */
987 		ret = isert_disconnected_handler(cma_id, event->event);
988 		break;
989 	case RDMA_CM_EVENT_REJECTED:       /* FALLTHRU */
990 	case RDMA_CM_EVENT_UNREACHABLE:    /* FALLTHRU */
991 	case RDMA_CM_EVENT_CONNECT_ERROR:
992 		ret = isert_connect_error(cma_id);
993 		break;
994 	default:
995 		isert_err("Unhandled RDMA CMA event: %d\n", event->event);
996 		break;
997 	}
998 
999 	return ret;
1000 }
1001 
1002 static int
1003 isert_post_recvm(struct isert_conn *isert_conn, u32 count)
1004 {
1005 	struct ib_recv_wr *rx_wr, *rx_wr_failed;
1006 	int i, ret;
1007 	struct iser_rx_desc *rx_desc;
1008 
1009 	for (rx_wr = isert_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
1010 		rx_desc = &isert_conn->rx_descs[i];
1011 		rx_wr->wr_id = (uintptr_t)rx_desc;
1012 		rx_wr->sg_list = &rx_desc->rx_sg;
1013 		rx_wr->num_sge = 1;
1014 		rx_wr->next = rx_wr + 1;
1015 	}
1016 	rx_wr--;
1017 	rx_wr->next = NULL; /* mark end of work requests list */
1018 
1019 	isert_conn->post_recv_buf_count += count;
1020 	ret = ib_post_recv(isert_conn->qp, isert_conn->rx_wr,
1021 			   &rx_wr_failed);
1022 	if (ret) {
1023 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
1024 		isert_conn->post_recv_buf_count -= count;
1025 	}
1026 
1027 	return ret;
1028 }
1029 
1030 static int
1031 isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
1032 {
1033 	struct ib_recv_wr *rx_wr_failed, rx_wr;
1034 	int ret;
1035 
1036 	rx_wr.wr_id = (uintptr_t)rx_desc;
1037 	rx_wr.sg_list = &rx_desc->rx_sg;
1038 	rx_wr.num_sge = 1;
1039 	rx_wr.next = NULL;
1040 
1041 	isert_conn->post_recv_buf_count++;
1042 	ret = ib_post_recv(isert_conn->qp, &rx_wr, &rx_wr_failed);
1043 	if (ret) {
1044 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
1045 		isert_conn->post_recv_buf_count--;
1046 	}
1047 
1048 	return ret;
1049 }
1050 
1051 static int
1052 isert_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
1053 {
1054 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1055 	struct ib_send_wr send_wr, *send_wr_failed;
1056 	int ret;
1057 
1058 	ib_dma_sync_single_for_device(ib_dev, tx_desc->dma_addr,
1059 				      ISER_HEADERS_LEN, DMA_TO_DEVICE);
1060 
1061 	send_wr.next	= NULL;
1062 	send_wr.wr_id	= (uintptr_t)tx_desc;
1063 	send_wr.sg_list	= tx_desc->tx_sg;
1064 	send_wr.num_sge	= tx_desc->num_sge;
1065 	send_wr.opcode	= IB_WR_SEND;
1066 	send_wr.send_flags = IB_SEND_SIGNALED;
1067 
1068 	ret = ib_post_send(isert_conn->qp, &send_wr, &send_wr_failed);
1069 	if (ret)
1070 		isert_err("ib_post_send() failed, ret: %d\n", ret);
1071 
1072 	return ret;
1073 }
1074 
1075 static void
1076 isert_create_send_desc(struct isert_conn *isert_conn,
1077 		       struct isert_cmd *isert_cmd,
1078 		       struct iser_tx_desc *tx_desc)
1079 {
1080 	struct isert_device *device = isert_conn->device;
1081 	struct ib_device *ib_dev = device->ib_device;
1082 
1083 	ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr,
1084 				   ISER_HEADERS_LEN, DMA_TO_DEVICE);
1085 
1086 	memset(&tx_desc->iser_header, 0, sizeof(struct iser_hdr));
1087 	tx_desc->iser_header.flags = ISER_VER;
1088 
1089 	tx_desc->num_sge = 1;
1090 	tx_desc->isert_cmd = isert_cmd;
1091 
1092 	if (tx_desc->tx_sg[0].lkey != device->pd->local_dma_lkey) {
1093 		tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
1094 		isert_dbg("tx_desc %p lkey mismatch, fixing\n", tx_desc);
1095 	}
1096 }
1097 
1098 static int
1099 isert_init_tx_hdrs(struct isert_conn *isert_conn,
1100 		   struct iser_tx_desc *tx_desc)
1101 {
1102 	struct isert_device *device = isert_conn->device;
1103 	struct ib_device *ib_dev = device->ib_device;
1104 	u64 dma_addr;
1105 
1106 	dma_addr = ib_dma_map_single(ib_dev, (void *)tx_desc,
1107 			ISER_HEADERS_LEN, DMA_TO_DEVICE);
1108 	if (ib_dma_mapping_error(ib_dev, dma_addr)) {
1109 		isert_err("ib_dma_mapping_error() failed\n");
1110 		return -ENOMEM;
1111 	}
1112 
1113 	tx_desc->dma_addr = dma_addr;
1114 	tx_desc->tx_sg[0].addr	= tx_desc->dma_addr;
1115 	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
1116 	tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
1117 
1118 	isert_dbg("Setup tx_sg[0].addr: 0x%llx length: %u lkey: 0x%x\n",
1119 		  tx_desc->tx_sg[0].addr, tx_desc->tx_sg[0].length,
1120 		  tx_desc->tx_sg[0].lkey);
1121 
1122 	return 0;
1123 }
1124 
1125 static void
1126 isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1127 		   struct ib_send_wr *send_wr)
1128 {
1129 	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
1130 
1131 	isert_cmd->rdma_wr.iser_ib_op = ISER_IB_SEND;
1132 	send_wr->wr_id = (uintptr_t)&isert_cmd->tx_desc;
1133 	send_wr->opcode = IB_WR_SEND;
1134 	send_wr->sg_list = &tx_desc->tx_sg[0];
1135 	send_wr->num_sge = isert_cmd->tx_desc.num_sge;
1136 	send_wr->send_flags = IB_SEND_SIGNALED;
1137 }
1138 
1139 static int
1140 isert_rdma_post_recvl(struct isert_conn *isert_conn)
1141 {
1142 	struct ib_recv_wr rx_wr, *rx_wr_fail;
1143 	struct ib_sge sge;
1144 	int ret;
1145 
1146 	memset(&sge, 0, sizeof(struct ib_sge));
1147 	sge.addr = isert_conn->login_req_dma;
1148 	sge.length = ISER_RX_LOGIN_SIZE;
1149 	sge.lkey = isert_conn->device->pd->local_dma_lkey;
1150 
1151 	isert_dbg("Setup sge: addr: %llx length: %d 0x%08x\n",
1152 		sge.addr, sge.length, sge.lkey);
1153 
1154 	memset(&rx_wr, 0, sizeof(struct ib_recv_wr));
1155 	rx_wr.wr_id = (uintptr_t)isert_conn->login_req_buf;
1156 	rx_wr.sg_list = &sge;
1157 	rx_wr.num_sge = 1;
1158 
1159 	isert_conn->post_recv_buf_count++;
1160 	ret = ib_post_recv(isert_conn->qp, &rx_wr, &rx_wr_fail);
1161 	if (ret) {
1162 		isert_err("ib_post_recv() failed: %d\n", ret);
1163 		isert_conn->post_recv_buf_count--;
1164 	}
1165 
1166 	return ret;
1167 }
1168 
1169 static int
1170 isert_put_login_tx(struct iscsi_conn *conn, struct iscsi_login *login,
1171 		   u32 length)
1172 {
1173 	struct isert_conn *isert_conn = conn->context;
1174 	struct isert_device *device = isert_conn->device;
1175 	struct ib_device *ib_dev = device->ib_device;
1176 	struct iser_tx_desc *tx_desc = &isert_conn->login_tx_desc;
1177 	int ret;
1178 
1179 	isert_create_send_desc(isert_conn, NULL, tx_desc);
1180 
1181 	memcpy(&tx_desc->iscsi_header, &login->rsp[0],
1182 	       sizeof(struct iscsi_hdr));
1183 
1184 	isert_init_tx_hdrs(isert_conn, tx_desc);
1185 
1186 	if (length > 0) {
1187 		struct ib_sge *tx_dsg = &tx_desc->tx_sg[1];
1188 
1189 		ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_rsp_dma,
1190 					   length, DMA_TO_DEVICE);
1191 
1192 		memcpy(isert_conn->login_rsp_buf, login->rsp_buf, length);
1193 
1194 		ib_dma_sync_single_for_device(ib_dev, isert_conn->login_rsp_dma,
1195 					      length, DMA_TO_DEVICE);
1196 
1197 		tx_dsg->addr	= isert_conn->login_rsp_dma;
1198 		tx_dsg->length	= length;
1199 		tx_dsg->lkey	= isert_conn->device->pd->local_dma_lkey;
1200 		tx_desc->num_sge = 2;
1201 	}
1202 	if (!login->login_failed) {
1203 		if (login->login_complete) {
1204 			if (!conn->sess->sess_ops->SessionType &&
1205 			    isert_conn->device->use_fastreg) {
1206 				ret = isert_conn_create_fastreg_pool(isert_conn);
1207 				if (ret) {
1208 					isert_err("Conn: %p failed to create"
1209 					       " fastreg pool\n", isert_conn);
1210 					return ret;
1211 				}
1212 			}
1213 
1214 			ret = isert_alloc_rx_descriptors(isert_conn);
1215 			if (ret)
1216 				return ret;
1217 
1218 			ret = isert_post_recvm(isert_conn,
1219 					       ISERT_QP_MAX_RECV_DTOS);
1220 			if (ret)
1221 				return ret;
1222 
1223 			/* Now we are in FULL_FEATURE phase */
1224 			mutex_lock(&isert_conn->mutex);
1225 			isert_conn->state = ISER_CONN_FULL_FEATURE;
1226 			mutex_unlock(&isert_conn->mutex);
1227 			goto post_send;
1228 		}
1229 
1230 		ret = isert_rdma_post_recvl(isert_conn);
1231 		if (ret)
1232 			return ret;
1233 	}
1234 post_send:
1235 	ret = isert_post_send(isert_conn, tx_desc);
1236 	if (ret)
1237 		return ret;
1238 
1239 	return 0;
1240 }
1241 
1242 static void
1243 isert_rx_login_req(struct isert_conn *isert_conn)
1244 {
1245 	struct iser_rx_desc *rx_desc = (void *)isert_conn->login_req_buf;
1246 	int rx_buflen = isert_conn->login_req_len;
1247 	struct iscsi_conn *conn = isert_conn->conn;
1248 	struct iscsi_login *login = conn->conn_login;
1249 	int size;
1250 
1251 	isert_info("conn %p\n", isert_conn);
1252 
1253 	WARN_ON_ONCE(!login);
1254 
1255 	if (login->first_request) {
1256 		struct iscsi_login_req *login_req =
1257 			(struct iscsi_login_req *)&rx_desc->iscsi_header;
1258 		/*
1259 		 * Setup the initial iscsi_login values from the leading
1260 		 * login request PDU.
1261 		 */
1262 		login->leading_connection = (!login_req->tsih) ? 1 : 0;
1263 		login->current_stage =
1264 			(login_req->flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK)
1265 			 >> 2;
1266 		login->version_min	= login_req->min_version;
1267 		login->version_max	= login_req->max_version;
1268 		memcpy(login->isid, login_req->isid, 6);
1269 		login->cmd_sn		= be32_to_cpu(login_req->cmdsn);
1270 		login->init_task_tag	= login_req->itt;
1271 		login->initial_exp_statsn = be32_to_cpu(login_req->exp_statsn);
1272 		login->cid		= be16_to_cpu(login_req->cid);
1273 		login->tsih		= be16_to_cpu(login_req->tsih);
1274 	}
1275 
1276 	memcpy(&login->req[0], (void *)&rx_desc->iscsi_header, ISCSI_HDR_LEN);
1277 
1278 	size = min(rx_buflen, MAX_KEY_VALUE_PAIRS);
1279 	isert_dbg("Using login payload size: %d, rx_buflen: %d "
1280 		  "MAX_KEY_VALUE_PAIRS: %d\n", size, rx_buflen,
1281 		  MAX_KEY_VALUE_PAIRS);
1282 	memcpy(login->req_buf, &rx_desc->data[0], size);
1283 
1284 	if (login->first_request) {
1285 		complete(&isert_conn->login_comp);
1286 		return;
1287 	}
1288 	schedule_delayed_work(&conn->login_work, 0);
1289 }
1290 
1291 static struct iscsi_cmd
1292 *isert_allocate_cmd(struct iscsi_conn *conn, struct iser_rx_desc *rx_desc)
1293 {
1294 	struct isert_conn *isert_conn = conn->context;
1295 	struct isert_cmd *isert_cmd;
1296 	struct iscsi_cmd *cmd;
1297 
1298 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
1299 	if (!cmd) {
1300 		isert_err("Unable to allocate iscsi_cmd + isert_cmd\n");
1301 		return NULL;
1302 	}
1303 	isert_cmd = iscsit_priv_cmd(cmd);
1304 	isert_cmd->conn = isert_conn;
1305 	isert_cmd->iscsi_cmd = cmd;
1306 	isert_cmd->rx_desc = rx_desc;
1307 
1308 	return cmd;
1309 }
1310 
1311 static int
1312 isert_handle_scsi_cmd(struct isert_conn *isert_conn,
1313 		      struct isert_cmd *isert_cmd, struct iscsi_cmd *cmd,
1314 		      struct iser_rx_desc *rx_desc, unsigned char *buf)
1315 {
1316 	struct iscsi_conn *conn = isert_conn->conn;
1317 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1318 	int imm_data, imm_data_len, unsol_data, sg_nents, rc;
1319 	bool dump_payload = false;
1320 	unsigned int data_len;
1321 
1322 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1323 	if (rc < 0)
1324 		return rc;
1325 
1326 	imm_data = cmd->immediate_data;
1327 	imm_data_len = cmd->first_burst_len;
1328 	unsol_data = cmd->unsolicited_data;
1329 	data_len = cmd->se_cmd.data_length;
1330 
1331 	if (imm_data && imm_data_len == data_len)
1332 		cmd->se_cmd.se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1333 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1334 	if (rc < 0) {
1335 		return 0;
1336 	} else if (rc > 0) {
1337 		dump_payload = true;
1338 		goto sequence_cmd;
1339 	}
1340 
1341 	if (!imm_data)
1342 		return 0;
1343 
1344 	if (imm_data_len != data_len) {
1345 		sg_nents = max(1UL, DIV_ROUND_UP(imm_data_len, PAGE_SIZE));
1346 		sg_copy_from_buffer(cmd->se_cmd.t_data_sg, sg_nents,
1347 				    &rx_desc->data[0], imm_data_len);
1348 		isert_dbg("Copy Immediate sg_nents: %u imm_data_len: %d\n",
1349 			  sg_nents, imm_data_len);
1350 	} else {
1351 		sg_init_table(&isert_cmd->sg, 1);
1352 		cmd->se_cmd.t_data_sg = &isert_cmd->sg;
1353 		cmd->se_cmd.t_data_nents = 1;
1354 		sg_set_buf(&isert_cmd->sg, &rx_desc->data[0], imm_data_len);
1355 		isert_dbg("Transfer Immediate imm_data_len: %d\n",
1356 			  imm_data_len);
1357 	}
1358 
1359 	cmd->write_data_done += imm_data_len;
1360 
1361 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
1362 		spin_lock_bh(&cmd->istate_lock);
1363 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1364 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1365 		spin_unlock_bh(&cmd->istate_lock);
1366 	}
1367 
1368 sequence_cmd:
1369 	rc = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1370 
1371 	if (!rc && dump_payload == false && unsol_data)
1372 		iscsit_set_unsoliticed_dataout(cmd);
1373 	else if (dump_payload && imm_data)
1374 		target_put_sess_cmd(&cmd->se_cmd);
1375 
1376 	return 0;
1377 }
1378 
1379 static int
1380 isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
1381 			   struct iser_rx_desc *rx_desc, unsigned char *buf)
1382 {
1383 	struct scatterlist *sg_start;
1384 	struct iscsi_conn *conn = isert_conn->conn;
1385 	struct iscsi_cmd *cmd = NULL;
1386 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1387 	u32 unsol_data_len = ntoh24(hdr->dlength);
1388 	int rc, sg_nents, sg_off, page_off;
1389 
1390 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1391 	if (rc < 0)
1392 		return rc;
1393 	else if (!cmd)
1394 		return 0;
1395 	/*
1396 	 * FIXME: Unexpected unsolicited_data out
1397 	 */
1398 	if (!cmd->unsolicited_data) {
1399 		isert_err("Received unexpected solicited data payload\n");
1400 		dump_stack();
1401 		return -1;
1402 	}
1403 
1404 	isert_dbg("Unsolicited DataOut unsol_data_len: %u, "
1405 		  "write_data_done: %u, data_length: %u\n",
1406 		  unsol_data_len,  cmd->write_data_done,
1407 		  cmd->se_cmd.data_length);
1408 
1409 	sg_off = cmd->write_data_done / PAGE_SIZE;
1410 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
1411 	sg_nents = max(1UL, DIV_ROUND_UP(unsol_data_len, PAGE_SIZE));
1412 	page_off = cmd->write_data_done % PAGE_SIZE;
1413 	/*
1414 	 * FIXME: Non page-aligned unsolicited_data out
1415 	 */
1416 	if (page_off) {
1417 		isert_err("unexpected non-page aligned data payload\n");
1418 		dump_stack();
1419 		return -1;
1420 	}
1421 	isert_dbg("Copying DataOut: sg_start: %p, sg_off: %u "
1422 		  "sg_nents: %u from %p %u\n", sg_start, sg_off,
1423 		  sg_nents, &rx_desc->data[0], unsol_data_len);
1424 
1425 	sg_copy_from_buffer(sg_start, sg_nents, &rx_desc->data[0],
1426 			    unsol_data_len);
1427 
1428 	rc = iscsit_check_dataout_payload(cmd, hdr, false);
1429 	if (rc < 0)
1430 		return rc;
1431 
1432 	/*
1433 	 * multiple data-outs on the same command can arrive -
1434 	 * so post the buffer before hand
1435 	 */
1436 	rc = isert_post_recv(isert_conn, rx_desc);
1437 	if (rc) {
1438 		isert_err("ib_post_recv failed with %d\n", rc);
1439 		return rc;
1440 	}
1441 	return 0;
1442 }
1443 
1444 static int
1445 isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1446 		     struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1447 		     unsigned char *buf)
1448 {
1449 	struct iscsi_conn *conn = isert_conn->conn;
1450 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1451 	int rc;
1452 
1453 	rc = iscsit_setup_nop_out(conn, cmd, hdr);
1454 	if (rc < 0)
1455 		return rc;
1456 	/*
1457 	 * FIXME: Add support for NOPOUT payload using unsolicited RDMA payload
1458 	 */
1459 
1460 	return iscsit_process_nop_out(conn, cmd, hdr);
1461 }
1462 
1463 static int
1464 isert_handle_text_cmd(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1465 		      struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
1466 		      struct iscsi_text *hdr)
1467 {
1468 	struct iscsi_conn *conn = isert_conn->conn;
1469 	u32 payload_length = ntoh24(hdr->dlength);
1470 	int rc;
1471 	unsigned char *text_in = NULL;
1472 
1473 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
1474 	if (rc < 0)
1475 		return rc;
1476 
1477 	if (payload_length) {
1478 		text_in = kzalloc(payload_length, GFP_KERNEL);
1479 		if (!text_in) {
1480 			isert_err("Unable to allocate text_in of payload_length: %u\n",
1481 				  payload_length);
1482 			return -ENOMEM;
1483 		}
1484 	}
1485 	cmd->text_in_ptr = text_in;
1486 
1487 	memcpy(cmd->text_in_ptr, &rx_desc->data[0], payload_length);
1488 
1489 	return iscsit_process_text_cmd(conn, cmd, hdr);
1490 }
1491 
1492 static int
1493 isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
1494 		uint32_t read_stag, uint64_t read_va,
1495 		uint32_t write_stag, uint64_t write_va)
1496 {
1497 	struct iscsi_hdr *hdr = &rx_desc->iscsi_header;
1498 	struct iscsi_conn *conn = isert_conn->conn;
1499 	struct iscsi_cmd *cmd;
1500 	struct isert_cmd *isert_cmd;
1501 	int ret = -EINVAL;
1502 	u8 opcode = (hdr->opcode & ISCSI_OPCODE_MASK);
1503 
1504 	if (conn->sess->sess_ops->SessionType &&
1505 	   (!(opcode & ISCSI_OP_TEXT) || !(opcode & ISCSI_OP_LOGOUT))) {
1506 		isert_err("Got illegal opcode: 0x%02x in SessionType=Discovery,"
1507 			  " ignoring\n", opcode);
1508 		return 0;
1509 	}
1510 
1511 	switch (opcode) {
1512 	case ISCSI_OP_SCSI_CMD:
1513 		cmd = isert_allocate_cmd(conn, rx_desc);
1514 		if (!cmd)
1515 			break;
1516 
1517 		isert_cmd = iscsit_priv_cmd(cmd);
1518 		isert_cmd->read_stag = read_stag;
1519 		isert_cmd->read_va = read_va;
1520 		isert_cmd->write_stag = write_stag;
1521 		isert_cmd->write_va = write_va;
1522 
1523 		ret = isert_handle_scsi_cmd(isert_conn, isert_cmd, cmd,
1524 					rx_desc, (unsigned char *)hdr);
1525 		break;
1526 	case ISCSI_OP_NOOP_OUT:
1527 		cmd = isert_allocate_cmd(conn, rx_desc);
1528 		if (!cmd)
1529 			break;
1530 
1531 		isert_cmd = iscsit_priv_cmd(cmd);
1532 		ret = isert_handle_nop_out(isert_conn, isert_cmd, cmd,
1533 					   rx_desc, (unsigned char *)hdr);
1534 		break;
1535 	case ISCSI_OP_SCSI_DATA_OUT:
1536 		ret = isert_handle_iscsi_dataout(isert_conn, rx_desc,
1537 						(unsigned char *)hdr);
1538 		break;
1539 	case ISCSI_OP_SCSI_TMFUNC:
1540 		cmd = isert_allocate_cmd(conn, rx_desc);
1541 		if (!cmd)
1542 			break;
1543 
1544 		ret = iscsit_handle_task_mgt_cmd(conn, cmd,
1545 						(unsigned char *)hdr);
1546 		break;
1547 	case ISCSI_OP_LOGOUT:
1548 		cmd = isert_allocate_cmd(conn, rx_desc);
1549 		if (!cmd)
1550 			break;
1551 
1552 		ret = iscsit_handle_logout_cmd(conn, cmd, (unsigned char *)hdr);
1553 		break;
1554 	case ISCSI_OP_TEXT:
1555 		if (be32_to_cpu(hdr->ttt) != 0xFFFFFFFF)
1556 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
1557 		else
1558 			cmd = isert_allocate_cmd(conn, rx_desc);
1559 
1560 		if (!cmd)
1561 			break;
1562 
1563 		isert_cmd = iscsit_priv_cmd(cmd);
1564 		ret = isert_handle_text_cmd(isert_conn, isert_cmd, cmd,
1565 					    rx_desc, (struct iscsi_text *)hdr);
1566 		break;
1567 	default:
1568 		isert_err("Got unknown iSCSI OpCode: 0x%02x\n", opcode);
1569 		dump_stack();
1570 		break;
1571 	}
1572 
1573 	return ret;
1574 }
1575 
1576 static void
1577 isert_rx_do_work(struct iser_rx_desc *rx_desc, struct isert_conn *isert_conn)
1578 {
1579 	struct iser_hdr *iser_hdr = &rx_desc->iser_header;
1580 	uint64_t read_va = 0, write_va = 0;
1581 	uint32_t read_stag = 0, write_stag = 0;
1582 	int rc;
1583 
1584 	switch (iser_hdr->flags & 0xF0) {
1585 	case ISCSI_CTRL:
1586 		if (iser_hdr->flags & ISER_RSV) {
1587 			read_stag = be32_to_cpu(iser_hdr->read_stag);
1588 			read_va = be64_to_cpu(iser_hdr->read_va);
1589 			isert_dbg("ISER_RSV: read_stag: 0x%x read_va: 0x%llx\n",
1590 				  read_stag, (unsigned long long)read_va);
1591 		}
1592 		if (iser_hdr->flags & ISER_WSV) {
1593 			write_stag = be32_to_cpu(iser_hdr->write_stag);
1594 			write_va = be64_to_cpu(iser_hdr->write_va);
1595 			isert_dbg("ISER_WSV: write_stag: 0x%x write_va: 0x%llx\n",
1596 				  write_stag, (unsigned long long)write_va);
1597 		}
1598 
1599 		isert_dbg("ISER ISCSI_CTRL PDU\n");
1600 		break;
1601 	case ISER_HELLO:
1602 		isert_err("iSER Hello message\n");
1603 		break;
1604 	default:
1605 		isert_warn("Unknown iSER hdr flags: 0x%02x\n", iser_hdr->flags);
1606 		break;
1607 	}
1608 
1609 	rc = isert_rx_opcode(isert_conn, rx_desc,
1610 			     read_stag, read_va, write_stag, write_va);
1611 }
1612 
1613 static void
1614 isert_rcv_completion(struct iser_rx_desc *desc,
1615 		     struct isert_conn *isert_conn,
1616 		     u32 xfer_len)
1617 {
1618 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1619 	struct iscsi_hdr *hdr;
1620 	u64 rx_dma;
1621 	int rx_buflen;
1622 
1623 	if ((char *)desc == isert_conn->login_req_buf) {
1624 		rx_dma = isert_conn->login_req_dma;
1625 		rx_buflen = ISER_RX_LOGIN_SIZE;
1626 		isert_dbg("login_buf: Using rx_dma: 0x%llx, rx_buflen: %d\n",
1627 			 rx_dma, rx_buflen);
1628 	} else {
1629 		rx_dma = desc->dma_addr;
1630 		rx_buflen = ISER_RX_PAYLOAD_SIZE;
1631 		isert_dbg("req_buf: Using rx_dma: 0x%llx, rx_buflen: %d\n",
1632 			 rx_dma, rx_buflen);
1633 	}
1634 
1635 	ib_dma_sync_single_for_cpu(ib_dev, rx_dma, rx_buflen, DMA_FROM_DEVICE);
1636 
1637 	hdr = &desc->iscsi_header;
1638 	isert_dbg("iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n",
1639 		 hdr->opcode, hdr->itt, hdr->flags,
1640 		 (int)(xfer_len - ISER_HEADERS_LEN));
1641 
1642 	if ((char *)desc == isert_conn->login_req_buf) {
1643 		isert_conn->login_req_len = xfer_len - ISER_HEADERS_LEN;
1644 		if (isert_conn->conn) {
1645 			struct iscsi_login *login = isert_conn->conn->conn_login;
1646 
1647 			if (login && !login->first_request)
1648 				isert_rx_login_req(isert_conn);
1649 		}
1650 		mutex_lock(&isert_conn->mutex);
1651 		complete(&isert_conn->login_req_comp);
1652 		mutex_unlock(&isert_conn->mutex);
1653 	} else {
1654 		isert_rx_do_work(desc, isert_conn);
1655 	}
1656 
1657 	ib_dma_sync_single_for_device(ib_dev, rx_dma, rx_buflen,
1658 				      DMA_FROM_DEVICE);
1659 
1660 	isert_conn->post_recv_buf_count--;
1661 }
1662 
1663 static int
1664 isert_map_data_buf(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1665 		   struct scatterlist *sg, u32 nents, u32 length, u32 offset,
1666 		   enum iser_ib_op_code op, struct isert_data_buf *data)
1667 {
1668 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1669 
1670 	data->dma_dir = op == ISER_IB_RDMA_WRITE ?
1671 			      DMA_TO_DEVICE : DMA_FROM_DEVICE;
1672 
1673 	data->len = length - offset;
1674 	data->offset = offset;
1675 	data->sg_off = data->offset / PAGE_SIZE;
1676 
1677 	data->sg = &sg[data->sg_off];
1678 	data->nents = min_t(unsigned int, nents - data->sg_off,
1679 					  ISCSI_ISER_SG_TABLESIZE);
1680 	data->len = min_t(unsigned int, data->len, ISCSI_ISER_SG_TABLESIZE *
1681 					PAGE_SIZE);
1682 
1683 	data->dma_nents = ib_dma_map_sg(ib_dev, data->sg, data->nents,
1684 					data->dma_dir);
1685 	if (unlikely(!data->dma_nents)) {
1686 		isert_err("Cmd: unable to dma map SGs %p\n", sg);
1687 		return -EINVAL;
1688 	}
1689 
1690 	isert_dbg("Mapped cmd: %p count: %u sg: %p sg_nents: %u rdma_len %d\n",
1691 		  isert_cmd, data->dma_nents, data->sg, data->nents, data->len);
1692 
1693 	return 0;
1694 }
1695 
1696 static void
1697 isert_unmap_data_buf(struct isert_conn *isert_conn, struct isert_data_buf *data)
1698 {
1699 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1700 
1701 	ib_dma_unmap_sg(ib_dev, data->sg, data->nents, data->dma_dir);
1702 	memset(data, 0, sizeof(*data));
1703 }
1704 
1705 
1706 
1707 static void
1708 isert_unmap_cmd(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn)
1709 {
1710 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1711 
1712 	isert_dbg("Cmd %p\n", isert_cmd);
1713 
1714 	if (wr->data.sg) {
1715 		isert_dbg("Cmd %p unmap_sg op\n", isert_cmd);
1716 		isert_unmap_data_buf(isert_conn, &wr->data);
1717 	}
1718 
1719 	if (wr->send_wr) {
1720 		isert_dbg("Cmd %p free send_wr\n", isert_cmd);
1721 		kfree(wr->send_wr);
1722 		wr->send_wr = NULL;
1723 	}
1724 
1725 	if (wr->ib_sge) {
1726 		isert_dbg("Cmd %p free ib_sge\n", isert_cmd);
1727 		kfree(wr->ib_sge);
1728 		wr->ib_sge = NULL;
1729 	}
1730 }
1731 
1732 static void
1733 isert_unreg_rdma(struct isert_cmd *isert_cmd, struct isert_conn *isert_conn)
1734 {
1735 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1736 
1737 	isert_dbg("Cmd %p\n", isert_cmd);
1738 
1739 	if (wr->fr_desc) {
1740 		isert_dbg("Cmd %p free fr_desc %p\n", isert_cmd, wr->fr_desc);
1741 		if (wr->fr_desc->ind & ISERT_PROTECTED) {
1742 			isert_unmap_data_buf(isert_conn, &wr->prot);
1743 			wr->fr_desc->ind &= ~ISERT_PROTECTED;
1744 		}
1745 		spin_lock_bh(&isert_conn->pool_lock);
1746 		list_add_tail(&wr->fr_desc->list, &isert_conn->fr_pool);
1747 		spin_unlock_bh(&isert_conn->pool_lock);
1748 		wr->fr_desc = NULL;
1749 	}
1750 
1751 	if (wr->data.sg) {
1752 		isert_dbg("Cmd %p unmap_sg op\n", isert_cmd);
1753 		isert_unmap_data_buf(isert_conn, &wr->data);
1754 	}
1755 
1756 	wr->ib_sge = NULL;
1757 	wr->send_wr = NULL;
1758 }
1759 
1760 static void
1761 isert_put_cmd(struct isert_cmd *isert_cmd, bool comp_err)
1762 {
1763 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1764 	struct isert_conn *isert_conn = isert_cmd->conn;
1765 	struct iscsi_conn *conn = isert_conn->conn;
1766 	struct isert_device *device = isert_conn->device;
1767 	struct iscsi_text_rsp *hdr;
1768 
1769 	isert_dbg("Cmd %p\n", isert_cmd);
1770 
1771 	switch (cmd->iscsi_opcode) {
1772 	case ISCSI_OP_SCSI_CMD:
1773 		spin_lock_bh(&conn->cmd_lock);
1774 		if (!list_empty(&cmd->i_conn_node))
1775 			list_del_init(&cmd->i_conn_node);
1776 		spin_unlock_bh(&conn->cmd_lock);
1777 
1778 		if (cmd->data_direction == DMA_TO_DEVICE) {
1779 			iscsit_stop_dataout_timer(cmd);
1780 			/*
1781 			 * Check for special case during comp_err where
1782 			 * WRITE_PENDING has been handed off from core,
1783 			 * but requires an extra target_put_sess_cmd()
1784 			 * before transport_generic_free_cmd() below.
1785 			 */
1786 			if (comp_err &&
1787 			    cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
1788 				struct se_cmd *se_cmd = &cmd->se_cmd;
1789 
1790 				target_put_sess_cmd(se_cmd);
1791 			}
1792 		}
1793 
1794 		device->unreg_rdma_mem(isert_cmd, isert_conn);
1795 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1796 		break;
1797 	case ISCSI_OP_SCSI_TMFUNC:
1798 		spin_lock_bh(&conn->cmd_lock);
1799 		if (!list_empty(&cmd->i_conn_node))
1800 			list_del_init(&cmd->i_conn_node);
1801 		spin_unlock_bh(&conn->cmd_lock);
1802 
1803 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1804 		break;
1805 	case ISCSI_OP_REJECT:
1806 	case ISCSI_OP_NOOP_OUT:
1807 	case ISCSI_OP_TEXT:
1808 		hdr = (struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1809 		/* If the continue bit is on, keep the command alive */
1810 		if (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)
1811 			break;
1812 
1813 		spin_lock_bh(&conn->cmd_lock);
1814 		if (!list_empty(&cmd->i_conn_node))
1815 			list_del_init(&cmd->i_conn_node);
1816 		spin_unlock_bh(&conn->cmd_lock);
1817 
1818 		/*
1819 		 * Handle special case for REJECT when iscsi_add_reject*() has
1820 		 * overwritten the original iscsi_opcode assignment, and the
1821 		 * associated cmd->se_cmd needs to be released.
1822 		 */
1823 		if (cmd->se_cmd.se_tfo != NULL) {
1824 			isert_dbg("Calling transport_generic_free_cmd for 0x%02x\n",
1825 				 cmd->iscsi_opcode);
1826 			transport_generic_free_cmd(&cmd->se_cmd, 0);
1827 			break;
1828 		}
1829 		/*
1830 		 * Fall-through
1831 		 */
1832 	default:
1833 		iscsit_release_cmd(cmd);
1834 		break;
1835 	}
1836 }
1837 
1838 static void
1839 isert_unmap_tx_desc(struct iser_tx_desc *tx_desc, struct ib_device *ib_dev)
1840 {
1841 	if (tx_desc->dma_addr != 0) {
1842 		isert_dbg("unmap single for tx_desc->dma_addr\n");
1843 		ib_dma_unmap_single(ib_dev, tx_desc->dma_addr,
1844 				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
1845 		tx_desc->dma_addr = 0;
1846 	}
1847 }
1848 
1849 static void
1850 isert_completion_put(struct iser_tx_desc *tx_desc, struct isert_cmd *isert_cmd,
1851 		     struct ib_device *ib_dev, bool comp_err)
1852 {
1853 	if (isert_cmd->pdu_buf_dma != 0) {
1854 		isert_dbg("unmap single for isert_cmd->pdu_buf_dma\n");
1855 		ib_dma_unmap_single(ib_dev, isert_cmd->pdu_buf_dma,
1856 				    isert_cmd->pdu_buf_len, DMA_TO_DEVICE);
1857 		isert_cmd->pdu_buf_dma = 0;
1858 	}
1859 
1860 	isert_unmap_tx_desc(tx_desc, ib_dev);
1861 	isert_put_cmd(isert_cmd, comp_err);
1862 }
1863 
1864 static int
1865 isert_check_pi_status(struct se_cmd *se_cmd, struct ib_mr *sig_mr)
1866 {
1867 	struct ib_mr_status mr_status;
1868 	int ret;
1869 
1870 	ret = ib_check_mr_status(sig_mr, IB_MR_CHECK_SIG_STATUS, &mr_status);
1871 	if (ret) {
1872 		isert_err("ib_check_mr_status failed, ret %d\n", ret);
1873 		goto fail_mr_status;
1874 	}
1875 
1876 	if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
1877 		u64 sec_offset_err;
1878 		u32 block_size = se_cmd->se_dev->dev_attrib.block_size + 8;
1879 
1880 		switch (mr_status.sig_err.err_type) {
1881 		case IB_SIG_BAD_GUARD:
1882 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1883 			break;
1884 		case IB_SIG_BAD_REFTAG:
1885 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1886 			break;
1887 		case IB_SIG_BAD_APPTAG:
1888 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED;
1889 			break;
1890 		}
1891 		sec_offset_err = mr_status.sig_err.sig_err_offset;
1892 		do_div(sec_offset_err, block_size);
1893 		se_cmd->bad_sector = sec_offset_err + se_cmd->t_task_lba;
1894 
1895 		isert_err("PI error found type %d at sector 0x%llx "
1896 			  "expected 0x%x vs actual 0x%x\n",
1897 			  mr_status.sig_err.err_type,
1898 			  (unsigned long long)se_cmd->bad_sector,
1899 			  mr_status.sig_err.expected,
1900 			  mr_status.sig_err.actual);
1901 		ret = 1;
1902 	}
1903 
1904 fail_mr_status:
1905 	return ret;
1906 }
1907 
1908 static void
1909 isert_completion_rdma_write(struct iser_tx_desc *tx_desc,
1910 			    struct isert_cmd *isert_cmd)
1911 {
1912 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1913 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1914 	struct se_cmd *se_cmd = &cmd->se_cmd;
1915 	struct isert_conn *isert_conn = isert_cmd->conn;
1916 	struct isert_device *device = isert_conn->device;
1917 	int ret = 0;
1918 
1919 	if (wr->fr_desc && wr->fr_desc->ind & ISERT_PROTECTED) {
1920 		ret = isert_check_pi_status(se_cmd,
1921 					    wr->fr_desc->pi_ctx->sig_mr);
1922 		wr->fr_desc->ind &= ~ISERT_PROTECTED;
1923 	}
1924 
1925 	device->unreg_rdma_mem(isert_cmd, isert_conn);
1926 	wr->send_wr_num = 0;
1927 	if (ret)
1928 		transport_send_check_condition_and_sense(se_cmd,
1929 							 se_cmd->pi_err, 0);
1930 	else
1931 		isert_put_response(isert_conn->conn, cmd);
1932 }
1933 
1934 static void
1935 isert_completion_rdma_read(struct iser_tx_desc *tx_desc,
1936 			   struct isert_cmd *isert_cmd)
1937 {
1938 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
1939 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1940 	struct se_cmd *se_cmd = &cmd->se_cmd;
1941 	struct isert_conn *isert_conn = isert_cmd->conn;
1942 	struct isert_device *device = isert_conn->device;
1943 	int ret = 0;
1944 
1945 	if (wr->fr_desc && wr->fr_desc->ind & ISERT_PROTECTED) {
1946 		ret = isert_check_pi_status(se_cmd,
1947 					    wr->fr_desc->pi_ctx->sig_mr);
1948 		wr->fr_desc->ind &= ~ISERT_PROTECTED;
1949 	}
1950 
1951 	iscsit_stop_dataout_timer(cmd);
1952 	device->unreg_rdma_mem(isert_cmd, isert_conn);
1953 	cmd->write_data_done = wr->data.len;
1954 	wr->send_wr_num = 0;
1955 
1956 	isert_dbg("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
1957 	spin_lock_bh(&cmd->istate_lock);
1958 	cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1959 	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1960 	spin_unlock_bh(&cmd->istate_lock);
1961 
1962 	if (ret) {
1963 		target_put_sess_cmd(se_cmd);
1964 		transport_send_check_condition_and_sense(se_cmd,
1965 							 se_cmd->pi_err, 0);
1966 	} else {
1967 		target_execute_cmd(se_cmd);
1968 	}
1969 }
1970 
1971 static void
1972 isert_do_control_comp(struct work_struct *work)
1973 {
1974 	struct isert_cmd *isert_cmd = container_of(work,
1975 			struct isert_cmd, comp_work);
1976 	struct isert_conn *isert_conn = isert_cmd->conn;
1977 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1978 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
1979 
1980 	isert_dbg("Cmd %p i_state %d\n", isert_cmd, cmd->i_state);
1981 
1982 	switch (cmd->i_state) {
1983 	case ISTATE_SEND_TASKMGTRSP:
1984 		iscsit_tmr_post_handler(cmd, cmd->conn);
1985 	case ISTATE_SEND_REJECT:   /* FALLTHRU */
1986 	case ISTATE_SEND_TEXTRSP:  /* FALLTHRU */
1987 		cmd->i_state = ISTATE_SENT_STATUS;
1988 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd,
1989 				     ib_dev, false);
1990 		break;
1991 	case ISTATE_SEND_LOGOUTRSP:
1992 		iscsit_logout_post_handler(cmd, cmd->conn);
1993 		break;
1994 	default:
1995 		isert_err("Unknown i_state %d\n", cmd->i_state);
1996 		dump_stack();
1997 		break;
1998 	}
1999 }
2000 
2001 static void
2002 isert_response_completion(struct iser_tx_desc *tx_desc,
2003 			  struct isert_cmd *isert_cmd,
2004 			  struct isert_conn *isert_conn,
2005 			  struct ib_device *ib_dev)
2006 {
2007 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
2008 
2009 	if (cmd->i_state == ISTATE_SEND_TASKMGTRSP ||
2010 	    cmd->i_state == ISTATE_SEND_LOGOUTRSP ||
2011 	    cmd->i_state == ISTATE_SEND_REJECT ||
2012 	    cmd->i_state == ISTATE_SEND_TEXTRSP) {
2013 		isert_unmap_tx_desc(tx_desc, ib_dev);
2014 
2015 		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
2016 		queue_work(isert_comp_wq, &isert_cmd->comp_work);
2017 		return;
2018 	}
2019 
2020 	cmd->i_state = ISTATE_SENT_STATUS;
2021 	isert_completion_put(tx_desc, isert_cmd, ib_dev, false);
2022 }
2023 
2024 static void
2025 isert_snd_completion(struct iser_tx_desc *tx_desc,
2026 		      struct isert_conn *isert_conn)
2027 {
2028 	struct ib_device *ib_dev = isert_conn->cm_id->device;
2029 	struct isert_cmd *isert_cmd = tx_desc->isert_cmd;
2030 	struct isert_rdma_wr *wr;
2031 
2032 	if (!isert_cmd) {
2033 		isert_unmap_tx_desc(tx_desc, ib_dev);
2034 		return;
2035 	}
2036 	wr = &isert_cmd->rdma_wr;
2037 
2038 	isert_dbg("Cmd %p iser_ib_op %d\n", isert_cmd, wr->iser_ib_op);
2039 
2040 	switch (wr->iser_ib_op) {
2041 	case ISER_IB_SEND:
2042 		isert_response_completion(tx_desc, isert_cmd,
2043 					  isert_conn, ib_dev);
2044 		break;
2045 	case ISER_IB_RDMA_WRITE:
2046 		isert_completion_rdma_write(tx_desc, isert_cmd);
2047 		break;
2048 	case ISER_IB_RDMA_READ:
2049 		isert_completion_rdma_read(tx_desc, isert_cmd);
2050 		break;
2051 	default:
2052 		isert_err("Unknown wr->iser_ib_op: 0x%x\n", wr->iser_ib_op);
2053 		dump_stack();
2054 		break;
2055 	}
2056 }
2057 
2058 /**
2059  * is_isert_tx_desc() - Indicate if the completion wr_id
2060  *     is a TX descriptor or not.
2061  * @isert_conn: iser connection
2062  * @wr_id: completion WR identifier
2063  *
2064  * Since we cannot rely on wc opcode in FLUSH errors
2065  * we must work around it by checking if the wr_id address
2066  * falls in the iser connection rx_descs buffer. If so
2067  * it is an RX descriptor, otherwize it is a TX.
2068  */
2069 static inline bool
2070 is_isert_tx_desc(struct isert_conn *isert_conn, void *wr_id)
2071 {
2072 	void *start = isert_conn->rx_descs;
2073 	int len = ISERT_QP_MAX_RECV_DTOS * sizeof(*isert_conn->rx_descs);
2074 
2075 	if (wr_id >= start && wr_id < start + len)
2076 		return false;
2077 
2078 	return true;
2079 }
2080 
2081 static void
2082 isert_cq_comp_err(struct isert_conn *isert_conn, struct ib_wc *wc)
2083 {
2084 	if (wc->wr_id == ISER_BEACON_WRID) {
2085 		isert_info("conn %p completing wait_comp_err\n",
2086 			   isert_conn);
2087 		complete(&isert_conn->wait_comp_err);
2088 	} else if (is_isert_tx_desc(isert_conn, (void *)(uintptr_t)wc->wr_id)) {
2089 		struct ib_device *ib_dev = isert_conn->cm_id->device;
2090 		struct isert_cmd *isert_cmd;
2091 		struct iser_tx_desc *desc;
2092 
2093 		desc = (struct iser_tx_desc *)(uintptr_t)wc->wr_id;
2094 		isert_cmd = desc->isert_cmd;
2095 		if (!isert_cmd)
2096 			isert_unmap_tx_desc(desc, ib_dev);
2097 		else
2098 			isert_completion_put(desc, isert_cmd, ib_dev, true);
2099 	} else {
2100 		isert_conn->post_recv_buf_count--;
2101 		if (!isert_conn->post_recv_buf_count)
2102 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
2103 	}
2104 }
2105 
2106 static void
2107 isert_handle_wc(struct ib_wc *wc)
2108 {
2109 	struct isert_conn *isert_conn;
2110 	struct iser_tx_desc *tx_desc;
2111 	struct iser_rx_desc *rx_desc;
2112 
2113 	isert_conn = wc->qp->qp_context;
2114 	if (likely(wc->status == IB_WC_SUCCESS)) {
2115 		if (wc->opcode == IB_WC_RECV) {
2116 			rx_desc = (struct iser_rx_desc *)(uintptr_t)wc->wr_id;
2117 			isert_rcv_completion(rx_desc, isert_conn, wc->byte_len);
2118 		} else {
2119 			tx_desc = (struct iser_tx_desc *)(uintptr_t)wc->wr_id;
2120 			isert_snd_completion(tx_desc, isert_conn);
2121 		}
2122 	} else {
2123 		if (wc->status != IB_WC_WR_FLUSH_ERR)
2124 			isert_err("%s (%d): wr id %llx vend_err %x\n",
2125 				  ib_wc_status_msg(wc->status), wc->status,
2126 				  wc->wr_id, wc->vendor_err);
2127 		else
2128 			isert_dbg("%s (%d): wr id %llx\n",
2129 				  ib_wc_status_msg(wc->status), wc->status,
2130 				  wc->wr_id);
2131 
2132 		if (wc->wr_id != ISER_FASTREG_LI_WRID)
2133 			isert_cq_comp_err(isert_conn, wc);
2134 	}
2135 }
2136 
2137 static void
2138 isert_cq_work(struct work_struct *work)
2139 {
2140 	enum { isert_poll_budget = 65536 };
2141 	struct isert_comp *comp = container_of(work, struct isert_comp,
2142 					       work);
2143 	struct ib_wc *const wcs = comp->wcs;
2144 	int i, n, completed = 0;
2145 
2146 	while ((n = ib_poll_cq(comp->cq, ARRAY_SIZE(comp->wcs), wcs)) > 0) {
2147 		for (i = 0; i < n; i++)
2148 			isert_handle_wc(&wcs[i]);
2149 
2150 		completed += n;
2151 		if (completed >= isert_poll_budget)
2152 			break;
2153 	}
2154 
2155 	ib_req_notify_cq(comp->cq, IB_CQ_NEXT_COMP);
2156 }
2157 
2158 static void
2159 isert_cq_callback(struct ib_cq *cq, void *context)
2160 {
2161 	struct isert_comp *comp = context;
2162 
2163 	queue_work(isert_comp_wq, &comp->work);
2164 }
2165 
2166 static int
2167 isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
2168 {
2169 	struct ib_send_wr *wr_failed;
2170 	int ret;
2171 
2172 	ret = isert_post_recv(isert_conn, isert_cmd->rx_desc);
2173 	if (ret) {
2174 		isert_err("ib_post_recv failed with %d\n", ret);
2175 		return ret;
2176 	}
2177 
2178 	ret = ib_post_send(isert_conn->qp, &isert_cmd->tx_desc.send_wr,
2179 			   &wr_failed);
2180 	if (ret) {
2181 		isert_err("ib_post_send failed with %d\n", ret);
2182 		return ret;
2183 	}
2184 	return ret;
2185 }
2186 
2187 static int
2188 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
2189 {
2190 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2191 	struct isert_conn *isert_conn = conn->context;
2192 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
2193 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
2194 				&isert_cmd->tx_desc.iscsi_header;
2195 
2196 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2197 	iscsit_build_rsp_pdu(cmd, conn, true, hdr);
2198 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2199 	/*
2200 	 * Attach SENSE DATA payload to iSCSI Response PDU
2201 	 */
2202 	if (cmd->se_cmd.sense_buffer &&
2203 	    ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
2204 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
2205 		struct isert_device *device = isert_conn->device;
2206 		struct ib_device *ib_dev = device->ib_device;
2207 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
2208 		u32 padding, pdu_len;
2209 
2210 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length,
2211 				   cmd->sense_buffer);
2212 		cmd->se_cmd.scsi_sense_length += sizeof(__be16);
2213 
2214 		padding = -(cmd->se_cmd.scsi_sense_length) & 3;
2215 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
2216 		pdu_len = cmd->se_cmd.scsi_sense_length + padding;
2217 
2218 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
2219 				(void *)cmd->sense_buffer, pdu_len,
2220 				DMA_TO_DEVICE);
2221 
2222 		isert_cmd->pdu_buf_len = pdu_len;
2223 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
2224 		tx_dsg->length	= pdu_len;
2225 		tx_dsg->lkey	= device->pd->local_dma_lkey;
2226 		isert_cmd->tx_desc.num_sge = 2;
2227 	}
2228 
2229 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
2230 
2231 	isert_dbg("Posting SCSI Response\n");
2232 
2233 	return isert_post_response(isert_conn, isert_cmd);
2234 }
2235 
2236 static void
2237 isert_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
2238 {
2239 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2240 	struct isert_conn *isert_conn = conn->context;
2241 	struct isert_device *device = isert_conn->device;
2242 
2243 	spin_lock_bh(&conn->cmd_lock);
2244 	if (!list_empty(&cmd->i_conn_node))
2245 		list_del_init(&cmd->i_conn_node);
2246 	spin_unlock_bh(&conn->cmd_lock);
2247 
2248 	if (cmd->data_direction == DMA_TO_DEVICE)
2249 		iscsit_stop_dataout_timer(cmd);
2250 
2251 	device->unreg_rdma_mem(isert_cmd, isert_conn);
2252 }
2253 
2254 static enum target_prot_op
2255 isert_get_sup_prot_ops(struct iscsi_conn *conn)
2256 {
2257 	struct isert_conn *isert_conn = conn->context;
2258 	struct isert_device *device = isert_conn->device;
2259 
2260 	if (conn->tpg->tpg_attrib.t10_pi) {
2261 		if (device->pi_capable) {
2262 			isert_info("conn %p PI offload enabled\n", isert_conn);
2263 			isert_conn->pi_support = true;
2264 			return TARGET_PROT_ALL;
2265 		}
2266 	}
2267 
2268 	isert_info("conn %p PI offload disabled\n", isert_conn);
2269 	isert_conn->pi_support = false;
2270 
2271 	return TARGET_PROT_NORMAL;
2272 }
2273 
2274 static int
2275 isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2276 		bool nopout_response)
2277 {
2278 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2279 	struct isert_conn *isert_conn = conn->context;
2280 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
2281 
2282 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2283 	iscsit_build_nopin_rsp(cmd, conn, (struct iscsi_nopin *)
2284 			       &isert_cmd->tx_desc.iscsi_header,
2285 			       nopout_response);
2286 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2287 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
2288 
2289 	isert_dbg("conn %p Posting NOPIN Response\n", isert_conn);
2290 
2291 	return isert_post_response(isert_conn, isert_cmd);
2292 }
2293 
2294 static int
2295 isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2296 {
2297 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2298 	struct isert_conn *isert_conn = conn->context;
2299 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
2300 
2301 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2302 	iscsit_build_logout_rsp(cmd, conn, (struct iscsi_logout_rsp *)
2303 				&isert_cmd->tx_desc.iscsi_header);
2304 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2305 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
2306 
2307 	isert_dbg("conn %p Posting Logout Response\n", isert_conn);
2308 
2309 	return isert_post_response(isert_conn, isert_cmd);
2310 }
2311 
2312 static int
2313 isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2314 {
2315 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2316 	struct isert_conn *isert_conn = conn->context;
2317 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
2318 
2319 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2320 	iscsit_build_task_mgt_rsp(cmd, conn, (struct iscsi_tm_rsp *)
2321 				  &isert_cmd->tx_desc.iscsi_header);
2322 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2323 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
2324 
2325 	isert_dbg("conn %p Posting Task Management Response\n", isert_conn);
2326 
2327 	return isert_post_response(isert_conn, isert_cmd);
2328 }
2329 
2330 static int
2331 isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2332 {
2333 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2334 	struct isert_conn *isert_conn = conn->context;
2335 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
2336 	struct isert_device *device = isert_conn->device;
2337 	struct ib_device *ib_dev = device->ib_device;
2338 	struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
2339 	struct iscsi_reject *hdr =
2340 		(struct iscsi_reject *)&isert_cmd->tx_desc.iscsi_header;
2341 
2342 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2343 	iscsit_build_reject(cmd, conn, hdr);
2344 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2345 
2346 	hton24(hdr->dlength, ISCSI_HDR_LEN);
2347 	isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
2348 			(void *)cmd->buf_ptr, ISCSI_HDR_LEN,
2349 			DMA_TO_DEVICE);
2350 	isert_cmd->pdu_buf_len = ISCSI_HDR_LEN;
2351 	tx_dsg->addr	= isert_cmd->pdu_buf_dma;
2352 	tx_dsg->length	= ISCSI_HDR_LEN;
2353 	tx_dsg->lkey	= device->pd->local_dma_lkey;
2354 	isert_cmd->tx_desc.num_sge = 2;
2355 
2356 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
2357 
2358 	isert_dbg("conn %p Posting Reject\n", isert_conn);
2359 
2360 	return isert_post_response(isert_conn, isert_cmd);
2361 }
2362 
2363 static int
2364 isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2365 {
2366 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2367 	struct isert_conn *isert_conn = conn->context;
2368 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
2369 	struct iscsi_text_rsp *hdr =
2370 		(struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
2371 	u32 txt_rsp_len;
2372 	int rc;
2373 
2374 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
2375 	rc = iscsit_build_text_rsp(cmd, conn, hdr, ISCSI_INFINIBAND);
2376 	if (rc < 0)
2377 		return rc;
2378 
2379 	txt_rsp_len = rc;
2380 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2381 
2382 	if (txt_rsp_len) {
2383 		struct isert_device *device = isert_conn->device;
2384 		struct ib_device *ib_dev = device->ib_device;
2385 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
2386 		void *txt_rsp_buf = cmd->buf_ptr;
2387 
2388 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
2389 				txt_rsp_buf, txt_rsp_len, DMA_TO_DEVICE);
2390 
2391 		isert_cmd->pdu_buf_len = txt_rsp_len;
2392 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
2393 		tx_dsg->length	= txt_rsp_len;
2394 		tx_dsg->lkey	= device->pd->local_dma_lkey;
2395 		isert_cmd->tx_desc.num_sge = 2;
2396 	}
2397 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
2398 
2399 	isert_dbg("conn %p Text Response\n", isert_conn);
2400 
2401 	return isert_post_response(isert_conn, isert_cmd);
2402 }
2403 
2404 static int
2405 isert_build_rdma_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
2406 		    struct ib_sge *ib_sge, struct ib_send_wr *send_wr,
2407 		    u32 data_left, u32 offset)
2408 {
2409 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
2410 	struct scatterlist *sg_start, *tmp_sg;
2411 	struct isert_device *device = isert_conn->device;
2412 	struct ib_device *ib_dev = device->ib_device;
2413 	u32 sg_off, page_off;
2414 	int i = 0, sg_nents;
2415 
2416 	sg_off = offset / PAGE_SIZE;
2417 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
2418 	sg_nents = min(cmd->se_cmd.t_data_nents - sg_off, isert_conn->max_sge);
2419 	page_off = offset % PAGE_SIZE;
2420 
2421 	send_wr->sg_list = ib_sge;
2422 	send_wr->wr_id = (uintptr_t)&isert_cmd->tx_desc;
2423 	/*
2424 	 * Perform mapping of TCM scatterlist memory ib_sge dma_addr.
2425 	 */
2426 	for_each_sg(sg_start, tmp_sg, sg_nents, i) {
2427 		isert_dbg("RDMA from SGL dma_addr: 0x%llx dma_len: %u, "
2428 			  "page_off: %u\n",
2429 			  (unsigned long long)tmp_sg->dma_address,
2430 			  tmp_sg->length, page_off);
2431 
2432 		ib_sge->addr = ib_sg_dma_address(ib_dev, tmp_sg) + page_off;
2433 		ib_sge->length = min_t(u32, data_left,
2434 				ib_sg_dma_len(ib_dev, tmp_sg) - page_off);
2435 		ib_sge->lkey = device->pd->local_dma_lkey;
2436 
2437 		isert_dbg("RDMA ib_sge: addr: 0x%llx  length: %u lkey: %x\n",
2438 			  ib_sge->addr, ib_sge->length, ib_sge->lkey);
2439 		page_off = 0;
2440 		data_left -= ib_sge->length;
2441 		if (!data_left)
2442 			break;
2443 		ib_sge++;
2444 		isert_dbg("Incrementing ib_sge pointer to %p\n", ib_sge);
2445 	}
2446 
2447 	send_wr->num_sge = ++i;
2448 	isert_dbg("Set outgoing sg_list: %p num_sg: %u from TCM SGLs\n",
2449 		  send_wr->sg_list, send_wr->num_sge);
2450 
2451 	return send_wr->num_sge;
2452 }
2453 
2454 static int
2455 isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2456 	       struct isert_rdma_wr *wr)
2457 {
2458 	struct se_cmd *se_cmd = &cmd->se_cmd;
2459 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2460 	struct isert_conn *isert_conn = conn->context;
2461 	struct isert_data_buf *data = &wr->data;
2462 	struct ib_send_wr *send_wr;
2463 	struct ib_sge *ib_sge;
2464 	u32 offset, data_len, data_left, rdma_write_max, va_offset = 0;
2465 	int ret = 0, i, ib_sge_cnt;
2466 
2467 	isert_cmd->tx_desc.isert_cmd = isert_cmd;
2468 
2469 	offset = wr->iser_ib_op == ISER_IB_RDMA_READ ? cmd->write_data_done : 0;
2470 	ret = isert_map_data_buf(isert_conn, isert_cmd, se_cmd->t_data_sg,
2471 				 se_cmd->t_data_nents, se_cmd->data_length,
2472 				 offset, wr->iser_ib_op, &wr->data);
2473 	if (ret)
2474 		return ret;
2475 
2476 	data_left = data->len;
2477 	offset = data->offset;
2478 
2479 	ib_sge = kzalloc(sizeof(struct ib_sge) * data->nents, GFP_KERNEL);
2480 	if (!ib_sge) {
2481 		isert_warn("Unable to allocate ib_sge\n");
2482 		ret = -ENOMEM;
2483 		goto unmap_cmd;
2484 	}
2485 	wr->ib_sge = ib_sge;
2486 
2487 	wr->send_wr_num = DIV_ROUND_UP(data->nents, isert_conn->max_sge);
2488 	wr->send_wr = kzalloc(sizeof(struct ib_send_wr) * wr->send_wr_num,
2489 				GFP_KERNEL);
2490 	if (!wr->send_wr) {
2491 		isert_dbg("Unable to allocate wr->send_wr\n");
2492 		ret = -ENOMEM;
2493 		goto unmap_cmd;
2494 	}
2495 
2496 	wr->isert_cmd = isert_cmd;
2497 	rdma_write_max = isert_conn->max_sge * PAGE_SIZE;
2498 
2499 	for (i = 0; i < wr->send_wr_num; i++) {
2500 		send_wr = &isert_cmd->rdma_wr.send_wr[i];
2501 		data_len = min(data_left, rdma_write_max);
2502 
2503 		send_wr->send_flags = 0;
2504 		if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2505 			send_wr->opcode = IB_WR_RDMA_WRITE;
2506 			send_wr->wr.rdma.remote_addr = isert_cmd->read_va + offset;
2507 			send_wr->wr.rdma.rkey = isert_cmd->read_stag;
2508 			if (i + 1 == wr->send_wr_num)
2509 				send_wr->next = &isert_cmd->tx_desc.send_wr;
2510 			else
2511 				send_wr->next = &wr->send_wr[i + 1];
2512 		} else {
2513 			send_wr->opcode = IB_WR_RDMA_READ;
2514 			send_wr->wr.rdma.remote_addr = isert_cmd->write_va + va_offset;
2515 			send_wr->wr.rdma.rkey = isert_cmd->write_stag;
2516 			if (i + 1 == wr->send_wr_num)
2517 				send_wr->send_flags = IB_SEND_SIGNALED;
2518 			else
2519 				send_wr->next = &wr->send_wr[i + 1];
2520 		}
2521 
2522 		ib_sge_cnt = isert_build_rdma_wr(isert_conn, isert_cmd, ib_sge,
2523 					send_wr, data_len, offset);
2524 		ib_sge += ib_sge_cnt;
2525 
2526 		offset += data_len;
2527 		va_offset += data_len;
2528 		data_left -= data_len;
2529 	}
2530 
2531 	return 0;
2532 unmap_cmd:
2533 	isert_unmap_data_buf(isert_conn, data);
2534 
2535 	return ret;
2536 }
2537 
2538 static int
2539 isert_map_fr_pagelist(struct ib_device *ib_dev,
2540 		      struct scatterlist *sg_start, int sg_nents, u64 *fr_pl)
2541 {
2542 	u64 start_addr, end_addr, page, chunk_start = 0;
2543 	struct scatterlist *tmp_sg;
2544 	int i = 0, new_chunk, last_ent, n_pages;
2545 
2546 	n_pages = 0;
2547 	new_chunk = 1;
2548 	last_ent = sg_nents - 1;
2549 	for_each_sg(sg_start, tmp_sg, sg_nents, i) {
2550 		start_addr = ib_sg_dma_address(ib_dev, tmp_sg);
2551 		if (new_chunk)
2552 			chunk_start = start_addr;
2553 		end_addr = start_addr + ib_sg_dma_len(ib_dev, tmp_sg);
2554 
2555 		isert_dbg("SGL[%d] dma_addr: 0x%llx len: %u\n",
2556 			  i, (unsigned long long)tmp_sg->dma_address,
2557 			  tmp_sg->length);
2558 
2559 		if ((end_addr & ~PAGE_MASK) && i < last_ent) {
2560 			new_chunk = 0;
2561 			continue;
2562 		}
2563 		new_chunk = 1;
2564 
2565 		page = chunk_start & PAGE_MASK;
2566 		do {
2567 			fr_pl[n_pages++] = page;
2568 			isert_dbg("Mapped page_list[%d] page_addr: 0x%llx\n",
2569 				  n_pages - 1, page);
2570 			page += PAGE_SIZE;
2571 		} while (page < end_addr);
2572 	}
2573 
2574 	return n_pages;
2575 }
2576 
2577 static inline void
2578 isert_inv_rkey(struct ib_send_wr *inv_wr, struct ib_mr *mr)
2579 {
2580 	u32 rkey;
2581 
2582 	memset(inv_wr, 0, sizeof(*inv_wr));
2583 	inv_wr->wr_id = ISER_FASTREG_LI_WRID;
2584 	inv_wr->opcode = IB_WR_LOCAL_INV;
2585 	inv_wr->ex.invalidate_rkey = mr->rkey;
2586 
2587 	/* Bump the key */
2588 	rkey = ib_inc_rkey(mr->rkey);
2589 	ib_update_fast_reg_key(mr, rkey);
2590 }
2591 
2592 static int
2593 isert_fast_reg_mr(struct isert_conn *isert_conn,
2594 		  struct fast_reg_descriptor *fr_desc,
2595 		  struct isert_data_buf *mem,
2596 		  enum isert_indicator ind,
2597 		  struct ib_sge *sge)
2598 {
2599 	struct isert_device *device = isert_conn->device;
2600 	struct ib_device *ib_dev = device->ib_device;
2601 	struct ib_mr *mr;
2602 	struct ib_fast_reg_page_list *frpl;
2603 	struct ib_send_wr fr_wr, inv_wr;
2604 	struct ib_send_wr *bad_wr, *wr = NULL;
2605 	int ret, pagelist_len;
2606 	u32 page_off;
2607 
2608 	if (mem->dma_nents == 1) {
2609 		sge->lkey = device->pd->local_dma_lkey;
2610 		sge->addr = ib_sg_dma_address(ib_dev, &mem->sg[0]);
2611 		sge->length = ib_sg_dma_len(ib_dev, &mem->sg[0]);
2612 		isert_dbg("sge: addr: 0x%llx  length: %u lkey: %x\n",
2613 			 sge->addr, sge->length, sge->lkey);
2614 		return 0;
2615 	}
2616 
2617 	if (ind == ISERT_DATA_KEY_VALID) {
2618 		/* Registering data buffer */
2619 		mr = fr_desc->data_mr;
2620 		frpl = fr_desc->data_frpl;
2621 	} else {
2622 		/* Registering protection buffer */
2623 		mr = fr_desc->pi_ctx->prot_mr;
2624 		frpl = fr_desc->pi_ctx->prot_frpl;
2625 	}
2626 
2627 	page_off = mem->offset % PAGE_SIZE;
2628 
2629 	isert_dbg("Use fr_desc %p sg_nents %d offset %u\n",
2630 		  fr_desc, mem->nents, mem->offset);
2631 
2632 	pagelist_len = isert_map_fr_pagelist(ib_dev, mem->sg, mem->nents,
2633 					     &frpl->page_list[0]);
2634 
2635 	if (!(fr_desc->ind & ind)) {
2636 		isert_inv_rkey(&inv_wr, mr);
2637 		wr = &inv_wr;
2638 	}
2639 
2640 	/* Prepare FASTREG WR */
2641 	memset(&fr_wr, 0, sizeof(fr_wr));
2642 	fr_wr.wr_id = ISER_FASTREG_LI_WRID;
2643 	fr_wr.opcode = IB_WR_FAST_REG_MR;
2644 	fr_wr.wr.fast_reg.iova_start = frpl->page_list[0] + page_off;
2645 	fr_wr.wr.fast_reg.page_list = frpl;
2646 	fr_wr.wr.fast_reg.page_list_len = pagelist_len;
2647 	fr_wr.wr.fast_reg.page_shift = PAGE_SHIFT;
2648 	fr_wr.wr.fast_reg.length = mem->len;
2649 	fr_wr.wr.fast_reg.rkey = mr->rkey;
2650 	fr_wr.wr.fast_reg.access_flags = IB_ACCESS_LOCAL_WRITE;
2651 
2652 	if (!wr)
2653 		wr = &fr_wr;
2654 	else
2655 		wr->next = &fr_wr;
2656 
2657 	ret = ib_post_send(isert_conn->qp, wr, &bad_wr);
2658 	if (ret) {
2659 		isert_err("fast registration failed, ret:%d\n", ret);
2660 		return ret;
2661 	}
2662 	fr_desc->ind &= ~ind;
2663 
2664 	sge->lkey = mr->lkey;
2665 	sge->addr = frpl->page_list[0] + page_off;
2666 	sge->length = mem->len;
2667 
2668 	isert_dbg("sge: addr: 0x%llx  length: %u lkey: %x\n",
2669 		  sge->addr, sge->length, sge->lkey);
2670 
2671 	return ret;
2672 }
2673 
2674 static inline void
2675 isert_set_dif_domain(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs,
2676 		     struct ib_sig_domain *domain)
2677 {
2678 	domain->sig_type = IB_SIG_TYPE_T10_DIF;
2679 	domain->sig.dif.bg_type = IB_T10DIF_CRC;
2680 	domain->sig.dif.pi_interval = se_cmd->se_dev->dev_attrib.block_size;
2681 	domain->sig.dif.ref_tag = se_cmd->reftag_seed;
2682 	/*
2683 	 * At the moment we hard code those, but if in the future
2684 	 * the target core would like to use it, we will take it
2685 	 * from se_cmd.
2686 	 */
2687 	domain->sig.dif.apptag_check_mask = 0xffff;
2688 	domain->sig.dif.app_escape = true;
2689 	domain->sig.dif.ref_escape = true;
2690 	if (se_cmd->prot_type == TARGET_DIF_TYPE1_PROT ||
2691 	    se_cmd->prot_type == TARGET_DIF_TYPE2_PROT)
2692 		domain->sig.dif.ref_remap = true;
2693 };
2694 
2695 static int
2696 isert_set_sig_attrs(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs)
2697 {
2698 	switch (se_cmd->prot_op) {
2699 	case TARGET_PROT_DIN_INSERT:
2700 	case TARGET_PROT_DOUT_STRIP:
2701 		sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
2702 		isert_set_dif_domain(se_cmd, sig_attrs, &sig_attrs->wire);
2703 		break;
2704 	case TARGET_PROT_DOUT_INSERT:
2705 	case TARGET_PROT_DIN_STRIP:
2706 		sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
2707 		isert_set_dif_domain(se_cmd, sig_attrs, &sig_attrs->mem);
2708 		break;
2709 	case TARGET_PROT_DIN_PASS:
2710 	case TARGET_PROT_DOUT_PASS:
2711 		isert_set_dif_domain(se_cmd, sig_attrs, &sig_attrs->wire);
2712 		isert_set_dif_domain(se_cmd, sig_attrs, &sig_attrs->mem);
2713 		break;
2714 	default:
2715 		isert_err("Unsupported PI operation %d\n", se_cmd->prot_op);
2716 		return -EINVAL;
2717 	}
2718 
2719 	return 0;
2720 }
2721 
2722 static inline u8
2723 isert_set_prot_checks(u8 prot_checks)
2724 {
2725 	return (prot_checks & TARGET_DIF_CHECK_GUARD  ? 0xc0 : 0) |
2726 	       (prot_checks & TARGET_DIF_CHECK_REFTAG ? 0x30 : 0) |
2727 	       (prot_checks & TARGET_DIF_CHECK_REFTAG ? 0x0f : 0);
2728 }
2729 
2730 static int
2731 isert_reg_sig_mr(struct isert_conn *isert_conn,
2732 		 struct se_cmd *se_cmd,
2733 		 struct isert_rdma_wr *rdma_wr,
2734 		 struct fast_reg_descriptor *fr_desc)
2735 {
2736 	struct ib_send_wr sig_wr, inv_wr;
2737 	struct ib_send_wr *bad_wr, *wr = NULL;
2738 	struct pi_context *pi_ctx = fr_desc->pi_ctx;
2739 	struct ib_sig_attrs sig_attrs;
2740 	int ret;
2741 
2742 	memset(&sig_attrs, 0, sizeof(sig_attrs));
2743 	ret = isert_set_sig_attrs(se_cmd, &sig_attrs);
2744 	if (ret)
2745 		goto err;
2746 
2747 	sig_attrs.check_mask = isert_set_prot_checks(se_cmd->prot_checks);
2748 
2749 	if (!(fr_desc->ind & ISERT_SIG_KEY_VALID)) {
2750 		isert_inv_rkey(&inv_wr, pi_ctx->sig_mr);
2751 		wr = &inv_wr;
2752 	}
2753 
2754 	memset(&sig_wr, 0, sizeof(sig_wr));
2755 	sig_wr.opcode = IB_WR_REG_SIG_MR;
2756 	sig_wr.wr_id = ISER_FASTREG_LI_WRID;
2757 	sig_wr.sg_list = &rdma_wr->ib_sg[DATA];
2758 	sig_wr.num_sge = 1;
2759 	sig_wr.wr.sig_handover.access_flags = IB_ACCESS_LOCAL_WRITE;
2760 	sig_wr.wr.sig_handover.sig_attrs = &sig_attrs;
2761 	sig_wr.wr.sig_handover.sig_mr = pi_ctx->sig_mr;
2762 	if (se_cmd->t_prot_sg)
2763 		sig_wr.wr.sig_handover.prot = &rdma_wr->ib_sg[PROT];
2764 
2765 	if (!wr)
2766 		wr = &sig_wr;
2767 	else
2768 		wr->next = &sig_wr;
2769 
2770 	ret = ib_post_send(isert_conn->qp, wr, &bad_wr);
2771 	if (ret) {
2772 		isert_err("fast registration failed, ret:%d\n", ret);
2773 		goto err;
2774 	}
2775 	fr_desc->ind &= ~ISERT_SIG_KEY_VALID;
2776 
2777 	rdma_wr->ib_sg[SIG].lkey = pi_ctx->sig_mr->lkey;
2778 	rdma_wr->ib_sg[SIG].addr = 0;
2779 	rdma_wr->ib_sg[SIG].length = se_cmd->data_length;
2780 	if (se_cmd->prot_op != TARGET_PROT_DIN_STRIP &&
2781 	    se_cmd->prot_op != TARGET_PROT_DOUT_INSERT)
2782 		/*
2783 		 * We have protection guards on the wire
2784 		 * so we need to set a larget transfer
2785 		 */
2786 		rdma_wr->ib_sg[SIG].length += se_cmd->prot_length;
2787 
2788 	isert_dbg("sig_sge: addr: 0x%llx  length: %u lkey: %x\n",
2789 		  rdma_wr->ib_sg[SIG].addr, rdma_wr->ib_sg[SIG].length,
2790 		  rdma_wr->ib_sg[SIG].lkey);
2791 err:
2792 	return ret;
2793 }
2794 
2795 static int
2796 isert_handle_prot_cmd(struct isert_conn *isert_conn,
2797 		      struct isert_cmd *isert_cmd,
2798 		      struct isert_rdma_wr *wr)
2799 {
2800 	struct isert_device *device = isert_conn->device;
2801 	struct se_cmd *se_cmd = &isert_cmd->iscsi_cmd->se_cmd;
2802 	int ret;
2803 
2804 	if (!wr->fr_desc->pi_ctx) {
2805 		ret = isert_create_pi_ctx(wr->fr_desc,
2806 					  device->ib_device,
2807 					  device->pd);
2808 		if (ret) {
2809 			isert_err("conn %p failed to allocate pi_ctx\n",
2810 				  isert_conn);
2811 			return ret;
2812 		}
2813 	}
2814 
2815 	if (se_cmd->t_prot_sg) {
2816 		ret = isert_map_data_buf(isert_conn, isert_cmd,
2817 					 se_cmd->t_prot_sg,
2818 					 se_cmd->t_prot_nents,
2819 					 se_cmd->prot_length,
2820 					 0, wr->iser_ib_op, &wr->prot);
2821 		if (ret) {
2822 			isert_err("conn %p failed to map protection buffer\n",
2823 				  isert_conn);
2824 			return ret;
2825 		}
2826 
2827 		memset(&wr->ib_sg[PROT], 0, sizeof(wr->ib_sg[PROT]));
2828 		ret = isert_fast_reg_mr(isert_conn, wr->fr_desc, &wr->prot,
2829 					ISERT_PROT_KEY_VALID, &wr->ib_sg[PROT]);
2830 		if (ret) {
2831 			isert_err("conn %p failed to fast reg mr\n",
2832 				  isert_conn);
2833 			goto unmap_prot_cmd;
2834 		}
2835 	}
2836 
2837 	ret = isert_reg_sig_mr(isert_conn, se_cmd, wr, wr->fr_desc);
2838 	if (ret) {
2839 		isert_err("conn %p failed to fast reg mr\n",
2840 			  isert_conn);
2841 		goto unmap_prot_cmd;
2842 	}
2843 	wr->fr_desc->ind |= ISERT_PROTECTED;
2844 
2845 	return 0;
2846 
2847 unmap_prot_cmd:
2848 	if (se_cmd->t_prot_sg)
2849 		isert_unmap_data_buf(isert_conn, &wr->prot);
2850 
2851 	return ret;
2852 }
2853 
2854 static int
2855 isert_reg_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2856 	       struct isert_rdma_wr *wr)
2857 {
2858 	struct se_cmd *se_cmd = &cmd->se_cmd;
2859 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2860 	struct isert_conn *isert_conn = conn->context;
2861 	struct fast_reg_descriptor *fr_desc = NULL;
2862 	struct ib_send_wr *send_wr;
2863 	struct ib_sge *ib_sg;
2864 	u32 offset;
2865 	int ret = 0;
2866 	unsigned long flags;
2867 
2868 	isert_cmd->tx_desc.isert_cmd = isert_cmd;
2869 
2870 	offset = wr->iser_ib_op == ISER_IB_RDMA_READ ? cmd->write_data_done : 0;
2871 	ret = isert_map_data_buf(isert_conn, isert_cmd, se_cmd->t_data_sg,
2872 				 se_cmd->t_data_nents, se_cmd->data_length,
2873 				 offset, wr->iser_ib_op, &wr->data);
2874 	if (ret)
2875 		return ret;
2876 
2877 	if (wr->data.dma_nents != 1 || isert_prot_cmd(isert_conn, se_cmd)) {
2878 		spin_lock_irqsave(&isert_conn->pool_lock, flags);
2879 		fr_desc = list_first_entry(&isert_conn->fr_pool,
2880 					   struct fast_reg_descriptor, list);
2881 		list_del(&fr_desc->list);
2882 		spin_unlock_irqrestore(&isert_conn->pool_lock, flags);
2883 		wr->fr_desc = fr_desc;
2884 	}
2885 
2886 	ret = isert_fast_reg_mr(isert_conn, fr_desc, &wr->data,
2887 				ISERT_DATA_KEY_VALID, &wr->ib_sg[DATA]);
2888 	if (ret)
2889 		goto unmap_cmd;
2890 
2891 	if (isert_prot_cmd(isert_conn, se_cmd)) {
2892 		ret = isert_handle_prot_cmd(isert_conn, isert_cmd, wr);
2893 		if (ret)
2894 			goto unmap_cmd;
2895 
2896 		ib_sg = &wr->ib_sg[SIG];
2897 	} else {
2898 		ib_sg = &wr->ib_sg[DATA];
2899 	}
2900 
2901 	memcpy(&wr->s_ib_sge, ib_sg, sizeof(*ib_sg));
2902 	wr->ib_sge = &wr->s_ib_sge;
2903 	wr->send_wr_num = 1;
2904 	memset(&wr->s_send_wr, 0, sizeof(*send_wr));
2905 	wr->send_wr = &wr->s_send_wr;
2906 	wr->isert_cmd = isert_cmd;
2907 
2908 	send_wr = &isert_cmd->rdma_wr.s_send_wr;
2909 	send_wr->sg_list = &wr->s_ib_sge;
2910 	send_wr->num_sge = 1;
2911 	send_wr->wr_id = (uintptr_t)&isert_cmd->tx_desc;
2912 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
2913 		send_wr->opcode = IB_WR_RDMA_WRITE;
2914 		send_wr->wr.rdma.remote_addr = isert_cmd->read_va;
2915 		send_wr->wr.rdma.rkey = isert_cmd->read_stag;
2916 		send_wr->send_flags = !isert_prot_cmd(isert_conn, se_cmd) ?
2917 				      0 : IB_SEND_SIGNALED;
2918 	} else {
2919 		send_wr->opcode = IB_WR_RDMA_READ;
2920 		send_wr->wr.rdma.remote_addr = isert_cmd->write_va;
2921 		send_wr->wr.rdma.rkey = isert_cmd->write_stag;
2922 		send_wr->send_flags = IB_SEND_SIGNALED;
2923 	}
2924 
2925 	return 0;
2926 
2927 unmap_cmd:
2928 	if (fr_desc) {
2929 		spin_lock_irqsave(&isert_conn->pool_lock, flags);
2930 		list_add_tail(&fr_desc->list, &isert_conn->fr_pool);
2931 		spin_unlock_irqrestore(&isert_conn->pool_lock, flags);
2932 	}
2933 	isert_unmap_data_buf(isert_conn, &wr->data);
2934 
2935 	return ret;
2936 }
2937 
2938 static int
2939 isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
2940 {
2941 	struct se_cmd *se_cmd = &cmd->se_cmd;
2942 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2943 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
2944 	struct isert_conn *isert_conn = conn->context;
2945 	struct isert_device *device = isert_conn->device;
2946 	struct ib_send_wr *wr_failed;
2947 	int rc;
2948 
2949 	isert_dbg("Cmd: %p RDMA_WRITE data_length: %u\n",
2950 		 isert_cmd, se_cmd->data_length);
2951 
2952 	wr->iser_ib_op = ISER_IB_RDMA_WRITE;
2953 	rc = device->reg_rdma_mem(conn, cmd, wr);
2954 	if (rc) {
2955 		isert_err("Cmd: %p failed to prepare RDMA res\n", isert_cmd);
2956 		return rc;
2957 	}
2958 
2959 	if (!isert_prot_cmd(isert_conn, se_cmd)) {
2960 		/*
2961 		 * Build isert_conn->tx_desc for iSCSI response PDU and attach
2962 		 */
2963 		isert_create_send_desc(isert_conn, isert_cmd,
2964 				       &isert_cmd->tx_desc);
2965 		iscsit_build_rsp_pdu(cmd, conn, true, (struct iscsi_scsi_rsp *)
2966 				     &isert_cmd->tx_desc.iscsi_header);
2967 		isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2968 		isert_init_send_wr(isert_conn, isert_cmd,
2969 				   &isert_cmd->tx_desc.send_wr);
2970 		isert_cmd->rdma_wr.s_send_wr.next = &isert_cmd->tx_desc.send_wr;
2971 		wr->send_wr_num += 1;
2972 
2973 		rc = isert_post_recv(isert_conn, isert_cmd->rx_desc);
2974 		if (rc) {
2975 			isert_err("ib_post_recv failed with %d\n", rc);
2976 			return rc;
2977 		}
2978 	}
2979 
2980 	rc = ib_post_send(isert_conn->qp, wr->send_wr, &wr_failed);
2981 	if (rc)
2982 		isert_warn("ib_post_send() failed for IB_WR_RDMA_WRITE\n");
2983 
2984 	if (!isert_prot_cmd(isert_conn, se_cmd))
2985 		isert_dbg("Cmd: %p posted RDMA_WRITE + Response for iSER Data "
2986 			 "READ\n", isert_cmd);
2987 	else
2988 		isert_dbg("Cmd: %p posted RDMA_WRITE for iSER Data READ\n",
2989 			 isert_cmd);
2990 
2991 	return 1;
2992 }
2993 
2994 static int
2995 isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
2996 {
2997 	struct se_cmd *se_cmd = &cmd->se_cmd;
2998 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2999 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
3000 	struct isert_conn *isert_conn = conn->context;
3001 	struct isert_device *device = isert_conn->device;
3002 	struct ib_send_wr *wr_failed;
3003 	int rc;
3004 
3005 	isert_dbg("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
3006 		 isert_cmd, se_cmd->data_length, cmd->write_data_done);
3007 	wr->iser_ib_op = ISER_IB_RDMA_READ;
3008 	rc = device->reg_rdma_mem(conn, cmd, wr);
3009 	if (rc) {
3010 		isert_err("Cmd: %p failed to prepare RDMA res\n", isert_cmd);
3011 		return rc;
3012 	}
3013 
3014 	rc = ib_post_send(isert_conn->qp, wr->send_wr, &wr_failed);
3015 	if (rc)
3016 		isert_warn("ib_post_send() failed for IB_WR_RDMA_READ\n");
3017 
3018 	isert_dbg("Cmd: %p posted RDMA_READ memory for ISER Data WRITE\n",
3019 		 isert_cmd);
3020 
3021 	return 0;
3022 }
3023 
3024 static int
3025 isert_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3026 {
3027 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
3028 	int ret = 0;
3029 
3030 	switch (state) {
3031 	case ISTATE_REMOVE:
3032 		spin_lock_bh(&conn->cmd_lock);
3033 		list_del_init(&cmd->i_conn_node);
3034 		spin_unlock_bh(&conn->cmd_lock);
3035 		isert_put_cmd(isert_cmd, true);
3036 		break;
3037 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3038 		ret = isert_put_nopin(cmd, conn, false);
3039 		break;
3040 	default:
3041 		isert_err("Unknown immediate state: 0x%02x\n", state);
3042 		ret = -EINVAL;
3043 		break;
3044 	}
3045 
3046 	return ret;
3047 }
3048 
3049 static int
3050 isert_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3051 {
3052 	struct isert_conn *isert_conn = conn->context;
3053 	int ret;
3054 
3055 	switch (state) {
3056 	case ISTATE_SEND_LOGOUTRSP:
3057 		ret = isert_put_logout_rsp(cmd, conn);
3058 		if (!ret)
3059 			isert_conn->logout_posted = true;
3060 		break;
3061 	case ISTATE_SEND_NOPIN:
3062 		ret = isert_put_nopin(cmd, conn, true);
3063 		break;
3064 	case ISTATE_SEND_TASKMGTRSP:
3065 		ret = isert_put_tm_rsp(cmd, conn);
3066 		break;
3067 	case ISTATE_SEND_REJECT:
3068 		ret = isert_put_reject(cmd, conn);
3069 		break;
3070 	case ISTATE_SEND_TEXTRSP:
3071 		ret = isert_put_text_rsp(cmd, conn);
3072 		break;
3073 	case ISTATE_SEND_STATUS:
3074 		/*
3075 		 * Special case for sending non GOOD SCSI status from TX thread
3076 		 * context during pre se_cmd excecution failure.
3077 		 */
3078 		ret = isert_put_response(conn, cmd);
3079 		break;
3080 	default:
3081 		isert_err("Unknown response state: 0x%02x\n", state);
3082 		ret = -EINVAL;
3083 		break;
3084 	}
3085 
3086 	return ret;
3087 }
3088 
3089 struct rdma_cm_id *
3090 isert_setup_id(struct isert_np *isert_np)
3091 {
3092 	struct iscsi_np *np = isert_np->np;
3093 	struct rdma_cm_id *id;
3094 	struct sockaddr *sa;
3095 	int ret;
3096 
3097 	sa = (struct sockaddr *)&np->np_sockaddr;
3098 	isert_dbg("ksockaddr: %p, sa: %p\n", &np->np_sockaddr, sa);
3099 
3100 	id = rdma_create_id(isert_cma_handler, isert_np,
3101 			    RDMA_PS_TCP, IB_QPT_RC);
3102 	if (IS_ERR(id)) {
3103 		isert_err("rdma_create_id() failed: %ld\n", PTR_ERR(id));
3104 		ret = PTR_ERR(id);
3105 		goto out;
3106 	}
3107 	isert_dbg("id %p context %p\n", id, id->context);
3108 
3109 	ret = rdma_bind_addr(id, sa);
3110 	if (ret) {
3111 		isert_err("rdma_bind_addr() failed: %d\n", ret);
3112 		goto out_id;
3113 	}
3114 
3115 	ret = rdma_listen(id, 0);
3116 	if (ret) {
3117 		isert_err("rdma_listen() failed: %d\n", ret);
3118 		goto out_id;
3119 	}
3120 
3121 	return id;
3122 out_id:
3123 	rdma_destroy_id(id);
3124 out:
3125 	return ERR_PTR(ret);
3126 }
3127 
3128 static int
3129 isert_setup_np(struct iscsi_np *np,
3130 	       struct sockaddr_storage *ksockaddr)
3131 {
3132 	struct isert_np *isert_np;
3133 	struct rdma_cm_id *isert_lid;
3134 	int ret;
3135 
3136 	isert_np = kzalloc(sizeof(struct isert_np), GFP_KERNEL);
3137 	if (!isert_np) {
3138 		isert_err("Unable to allocate struct isert_np\n");
3139 		return -ENOMEM;
3140 	}
3141 	sema_init(&isert_np->sem, 0);
3142 	mutex_init(&isert_np->mutex);
3143 	INIT_LIST_HEAD(&isert_np->accepted);
3144 	INIT_LIST_HEAD(&isert_np->pending);
3145 	isert_np->np = np;
3146 
3147 	/*
3148 	 * Setup the np->np_sockaddr from the passed sockaddr setup
3149 	 * in iscsi_target_configfs.c code..
3150 	 */
3151 	memcpy(&np->np_sockaddr, ksockaddr,
3152 	       sizeof(struct sockaddr_storage));
3153 
3154 	isert_lid = isert_setup_id(isert_np);
3155 	if (IS_ERR(isert_lid)) {
3156 		ret = PTR_ERR(isert_lid);
3157 		goto out;
3158 	}
3159 
3160 	isert_np->cm_id = isert_lid;
3161 	np->np_context = isert_np;
3162 
3163 	return 0;
3164 
3165 out:
3166 	kfree(isert_np);
3167 
3168 	return ret;
3169 }
3170 
3171 static int
3172 isert_rdma_accept(struct isert_conn *isert_conn)
3173 {
3174 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
3175 	struct rdma_conn_param cp;
3176 	int ret;
3177 
3178 	memset(&cp, 0, sizeof(struct rdma_conn_param));
3179 	cp.initiator_depth = isert_conn->initiator_depth;
3180 	cp.retry_count = 7;
3181 	cp.rnr_retry_count = 7;
3182 
3183 	ret = rdma_accept(cm_id, &cp);
3184 	if (ret) {
3185 		isert_err("rdma_accept() failed with: %d\n", ret);
3186 		return ret;
3187 	}
3188 
3189 	return 0;
3190 }
3191 
3192 static int
3193 isert_get_login_rx(struct iscsi_conn *conn, struct iscsi_login *login)
3194 {
3195 	struct isert_conn *isert_conn = conn->context;
3196 	int ret;
3197 
3198 	isert_info("before login_req comp conn: %p\n", isert_conn);
3199 	ret = wait_for_completion_interruptible(&isert_conn->login_req_comp);
3200 	if (ret) {
3201 		isert_err("isert_conn %p interrupted before got login req\n",
3202 			  isert_conn);
3203 		return ret;
3204 	}
3205 	reinit_completion(&isert_conn->login_req_comp);
3206 
3207 	/*
3208 	 * For login requests after the first PDU, isert_rx_login_req() will
3209 	 * kick schedule_delayed_work(&conn->login_work) as the packet is
3210 	 * received, which turns this callback from iscsi_target_do_login_rx()
3211 	 * into a NOP.
3212 	 */
3213 	if (!login->first_request)
3214 		return 0;
3215 
3216 	isert_rx_login_req(isert_conn);
3217 
3218 	isert_info("before login_comp conn: %p\n", conn);
3219 	ret = wait_for_completion_interruptible(&isert_conn->login_comp);
3220 	if (ret)
3221 		return ret;
3222 
3223 	isert_info("processing login->req: %p\n", login->req);
3224 
3225 	return 0;
3226 }
3227 
3228 static void
3229 isert_set_conn_info(struct iscsi_np *np, struct iscsi_conn *conn,
3230 		    struct isert_conn *isert_conn)
3231 {
3232 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
3233 	struct rdma_route *cm_route = &cm_id->route;
3234 
3235 	conn->login_family = np->np_sockaddr.ss_family;
3236 
3237 	conn->login_sockaddr = cm_route->addr.dst_addr;
3238 	conn->local_sockaddr = cm_route->addr.src_addr;
3239 }
3240 
3241 static int
3242 isert_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
3243 {
3244 	struct isert_np *isert_np = np->np_context;
3245 	struct isert_conn *isert_conn;
3246 	int ret;
3247 
3248 accept_wait:
3249 	ret = down_interruptible(&isert_np->sem);
3250 	if (ret)
3251 		return -ENODEV;
3252 
3253 	spin_lock_bh(&np->np_thread_lock);
3254 	if (np->np_thread_state >= ISCSI_NP_THREAD_RESET) {
3255 		spin_unlock_bh(&np->np_thread_lock);
3256 		isert_dbg("np_thread_state %d\n",
3257 			 np->np_thread_state);
3258 		/**
3259 		 * No point in stalling here when np_thread
3260 		 * is in state RESET/SHUTDOWN/EXIT - bail
3261 		 **/
3262 		return -ENODEV;
3263 	}
3264 	spin_unlock_bh(&np->np_thread_lock);
3265 
3266 	mutex_lock(&isert_np->mutex);
3267 	if (list_empty(&isert_np->pending)) {
3268 		mutex_unlock(&isert_np->mutex);
3269 		goto accept_wait;
3270 	}
3271 	isert_conn = list_first_entry(&isert_np->pending,
3272 			struct isert_conn, node);
3273 	list_del_init(&isert_conn->node);
3274 	mutex_unlock(&isert_np->mutex);
3275 
3276 	conn->context = isert_conn;
3277 	isert_conn->conn = conn;
3278 
3279 	isert_set_conn_info(np, conn, isert_conn);
3280 
3281 	isert_dbg("Processing isert_conn: %p\n", isert_conn);
3282 
3283 	return 0;
3284 }
3285 
3286 static void
3287 isert_free_np(struct iscsi_np *np)
3288 {
3289 	struct isert_np *isert_np = np->np_context;
3290 	struct isert_conn *isert_conn, *n;
3291 
3292 	if (isert_np->cm_id)
3293 		rdma_destroy_id(isert_np->cm_id);
3294 
3295 	/*
3296 	 * FIXME: At this point we don't have a good way to insure
3297 	 * that at this point we don't have hanging connections that
3298 	 * completed RDMA establishment but didn't start iscsi login
3299 	 * process. So work-around this by cleaning up what ever piled
3300 	 * up in accepted and pending lists.
3301 	 */
3302 	mutex_lock(&isert_np->mutex);
3303 	if (!list_empty(&isert_np->pending)) {
3304 		isert_info("Still have isert pending connections\n");
3305 		list_for_each_entry_safe(isert_conn, n,
3306 					 &isert_np->pending,
3307 					 node) {
3308 			isert_info("cleaning isert_conn %p state (%d)\n",
3309 				   isert_conn, isert_conn->state);
3310 			isert_connect_release(isert_conn);
3311 		}
3312 	}
3313 
3314 	if (!list_empty(&isert_np->accepted)) {
3315 		isert_info("Still have isert accepted connections\n");
3316 		list_for_each_entry_safe(isert_conn, n,
3317 					 &isert_np->accepted,
3318 					 node) {
3319 			isert_info("cleaning isert_conn %p state (%d)\n",
3320 				   isert_conn, isert_conn->state);
3321 			isert_connect_release(isert_conn);
3322 		}
3323 	}
3324 	mutex_unlock(&isert_np->mutex);
3325 
3326 	np->np_context = NULL;
3327 	kfree(isert_np);
3328 }
3329 
3330 static void isert_release_work(struct work_struct *work)
3331 {
3332 	struct isert_conn *isert_conn = container_of(work,
3333 						     struct isert_conn,
3334 						     release_work);
3335 
3336 	isert_info("Starting release conn %p\n", isert_conn);
3337 
3338 	wait_for_completion(&isert_conn->wait);
3339 
3340 	mutex_lock(&isert_conn->mutex);
3341 	isert_conn->state = ISER_CONN_DOWN;
3342 	mutex_unlock(&isert_conn->mutex);
3343 
3344 	isert_info("Destroying conn %p\n", isert_conn);
3345 	isert_put_conn(isert_conn);
3346 }
3347 
3348 static void
3349 isert_wait4logout(struct isert_conn *isert_conn)
3350 {
3351 	struct iscsi_conn *conn = isert_conn->conn;
3352 
3353 	isert_info("conn %p\n", isert_conn);
3354 
3355 	if (isert_conn->logout_posted) {
3356 		isert_info("conn %p wait for conn_logout_comp\n", isert_conn);
3357 		wait_for_completion_timeout(&conn->conn_logout_comp,
3358 					    SECONDS_FOR_LOGOUT_COMP * HZ);
3359 	}
3360 }
3361 
3362 static void
3363 isert_wait4cmds(struct iscsi_conn *conn)
3364 {
3365 	isert_info("iscsi_conn %p\n", conn);
3366 
3367 	if (conn->sess) {
3368 		target_sess_cmd_list_set_waiting(conn->sess->se_sess);
3369 		target_wait_for_sess_cmds(conn->sess->se_sess);
3370 	}
3371 }
3372 
3373 static void
3374 isert_wait4flush(struct isert_conn *isert_conn)
3375 {
3376 	struct ib_recv_wr *bad_wr;
3377 
3378 	isert_info("conn %p\n", isert_conn);
3379 
3380 	init_completion(&isert_conn->wait_comp_err);
3381 	isert_conn->beacon.wr_id = ISER_BEACON_WRID;
3382 	/* post an indication that all flush errors were consumed */
3383 	if (ib_post_recv(isert_conn->qp, &isert_conn->beacon, &bad_wr)) {
3384 		isert_err("conn %p failed to post beacon", isert_conn);
3385 		return;
3386 	}
3387 
3388 	wait_for_completion(&isert_conn->wait_comp_err);
3389 }
3390 
3391 /**
3392  * isert_put_unsol_pending_cmds() - Drop commands waiting for
3393  *     unsolicitate dataout
3394  * @conn:    iscsi connection
3395  *
3396  * We might still have commands that are waiting for unsolicited
3397  * dataouts messages. We must put the extra reference on those
3398  * before blocking on the target_wait_for_session_cmds
3399  */
3400 static void
3401 isert_put_unsol_pending_cmds(struct iscsi_conn *conn)
3402 {
3403 	struct iscsi_cmd *cmd, *tmp;
3404 	static LIST_HEAD(drop_cmd_list);
3405 
3406 	spin_lock_bh(&conn->cmd_lock);
3407 	list_for_each_entry_safe(cmd, tmp, &conn->conn_cmd_list, i_conn_node) {
3408 		if ((cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA) &&
3409 		    (cmd->write_data_done < conn->sess->sess_ops->FirstBurstLength) &&
3410 		    (cmd->write_data_done < cmd->se_cmd.data_length))
3411 			list_move_tail(&cmd->i_conn_node, &drop_cmd_list);
3412 	}
3413 	spin_unlock_bh(&conn->cmd_lock);
3414 
3415 	list_for_each_entry_safe(cmd, tmp, &drop_cmd_list, i_conn_node) {
3416 		list_del_init(&cmd->i_conn_node);
3417 		if (cmd->i_state != ISTATE_REMOVE) {
3418 			struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
3419 
3420 			isert_info("conn %p dropping cmd %p\n", conn, cmd);
3421 			isert_put_cmd(isert_cmd, true);
3422 		}
3423 	}
3424 }
3425 
3426 static void isert_wait_conn(struct iscsi_conn *conn)
3427 {
3428 	struct isert_conn *isert_conn = conn->context;
3429 
3430 	isert_info("Starting conn %p\n", isert_conn);
3431 
3432 	mutex_lock(&isert_conn->mutex);
3433 	/*
3434 	 * Only wait for wait_comp_err if the isert_conn made it
3435 	 * into full feature phase..
3436 	 */
3437 	if (isert_conn->state == ISER_CONN_INIT) {
3438 		mutex_unlock(&isert_conn->mutex);
3439 		return;
3440 	}
3441 	isert_conn_terminate(isert_conn);
3442 	mutex_unlock(&isert_conn->mutex);
3443 
3444 	isert_wait4flush(isert_conn);
3445 	isert_put_unsol_pending_cmds(conn);
3446 	isert_wait4cmds(conn);
3447 	isert_wait4logout(isert_conn);
3448 
3449 	queue_work(isert_release_wq, &isert_conn->release_work);
3450 }
3451 
3452 static void isert_free_conn(struct iscsi_conn *conn)
3453 {
3454 	struct isert_conn *isert_conn = conn->context;
3455 
3456 	isert_wait4flush(isert_conn);
3457 	isert_put_conn(isert_conn);
3458 }
3459 
3460 static struct iscsit_transport iser_target_transport = {
3461 	.name			= "IB/iSER",
3462 	.transport_type		= ISCSI_INFINIBAND,
3463 	.priv_size		= sizeof(struct isert_cmd),
3464 	.owner			= THIS_MODULE,
3465 	.iscsit_setup_np	= isert_setup_np,
3466 	.iscsit_accept_np	= isert_accept_np,
3467 	.iscsit_free_np		= isert_free_np,
3468 	.iscsit_wait_conn	= isert_wait_conn,
3469 	.iscsit_free_conn	= isert_free_conn,
3470 	.iscsit_get_login_rx	= isert_get_login_rx,
3471 	.iscsit_put_login_tx	= isert_put_login_tx,
3472 	.iscsit_immediate_queue	= isert_immediate_queue,
3473 	.iscsit_response_queue	= isert_response_queue,
3474 	.iscsit_get_dataout	= isert_get_dataout,
3475 	.iscsit_queue_data_in	= isert_put_datain,
3476 	.iscsit_queue_status	= isert_put_response,
3477 	.iscsit_aborted_task	= isert_aborted_task,
3478 	.iscsit_get_sup_prot_ops = isert_get_sup_prot_ops,
3479 };
3480 
3481 static int __init isert_init(void)
3482 {
3483 	int ret;
3484 
3485 	isert_comp_wq = alloc_workqueue("isert_comp_wq",
3486 					WQ_UNBOUND | WQ_HIGHPRI, 0);
3487 	if (!isert_comp_wq) {
3488 		isert_err("Unable to allocate isert_comp_wq\n");
3489 		ret = -ENOMEM;
3490 		return -ENOMEM;
3491 	}
3492 
3493 	isert_release_wq = alloc_workqueue("isert_release_wq", WQ_UNBOUND,
3494 					WQ_UNBOUND_MAX_ACTIVE);
3495 	if (!isert_release_wq) {
3496 		isert_err("Unable to allocate isert_release_wq\n");
3497 		ret = -ENOMEM;
3498 		goto destroy_comp_wq;
3499 	}
3500 
3501 	iscsit_register_transport(&iser_target_transport);
3502 	isert_info("iSER_TARGET[0] - Loaded iser_target_transport\n");
3503 
3504 	return 0;
3505 
3506 destroy_comp_wq:
3507 	destroy_workqueue(isert_comp_wq);
3508 
3509 	return ret;
3510 }
3511 
3512 static void __exit isert_exit(void)
3513 {
3514 	flush_scheduled_work();
3515 	destroy_workqueue(isert_release_wq);
3516 	destroy_workqueue(isert_comp_wq);
3517 	iscsit_unregister_transport(&iser_target_transport);
3518 	isert_info("iSER_TARGET[0] - Released iser_target_transport\n");
3519 }
3520 
3521 MODULE_DESCRIPTION("iSER-Target for mainline target infrastructure");
3522 MODULE_VERSION("1.0");
3523 MODULE_AUTHOR("nab@Linux-iSCSI.org");
3524 MODULE_LICENSE("GPL");
3525 
3526 module_init(isert_init);
3527 module_exit(isert_exit);
3528