xref: /linux/drivers/infiniband/ulp/isert/ib_isert.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * This file contains iSCSI extentions for RDMA (iSER) Verbs
4  *
5  * (c) Copyright 2013 Datera, Inc.
6  *
7  * Nicholas A. Bellinger <nab@linux-iscsi.org>
8  *
9  ****************************************************************************/
10 
11 #include <linux/string.h>
12 #include <linux/module.h>
13 #include <linux/scatterlist.h>
14 #include <linux/socket.h>
15 #include <linux/in.h>
16 #include <linux/in6.h>
17 #include <rdma/ib_verbs.h>
18 #include <rdma/ib_cm.h>
19 #include <rdma/rdma_cm.h>
20 #include <target/target_core_base.h>
21 #include <target/target_core_fabric.h>
22 #include <target/iscsi/iscsi_transport.h>
23 #include <linux/semaphore.h>
24 
25 #include "ib_isert.h"
26 
27 static int isert_debug_level;
28 module_param_named(debug_level, isert_debug_level, int, 0644);
29 MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:0)");
30 
31 static int isert_sg_tablesize_set(const char *val,
32 				  const struct kernel_param *kp);
33 static const struct kernel_param_ops sg_tablesize_ops = {
34 	.set = isert_sg_tablesize_set,
35 	.get = param_get_int,
36 };
37 
38 static int isert_sg_tablesize = ISCSI_ISER_MIN_SG_TABLESIZE;
39 module_param_cb(sg_tablesize, &sg_tablesize_ops, &isert_sg_tablesize, 0644);
40 MODULE_PARM_DESC(sg_tablesize,
41 		 "Number of gather/scatter entries in a single scsi command, should >= 128 (default: 128, max: 4096)");
42 
43 static DEFINE_MUTEX(device_list_mutex);
44 static LIST_HEAD(device_list);
45 static struct workqueue_struct *isert_login_wq;
46 static struct workqueue_struct *isert_comp_wq;
47 static struct workqueue_struct *isert_release_wq;
48 
49 static int
50 isert_put_response(struct iscsit_conn *conn, struct iscsit_cmd *cmd);
51 static int
52 isert_login_post_recv(struct isert_conn *isert_conn);
53 static int
54 isert_rdma_accept(struct isert_conn *isert_conn);
55 struct rdma_cm_id *isert_setup_id(struct isert_np *isert_np);
56 
57 static void isert_release_work(struct work_struct *work);
58 static void isert_recv_done(struct ib_cq *cq, struct ib_wc *wc);
59 static void isert_send_done(struct ib_cq *cq, struct ib_wc *wc);
60 static void isert_login_recv_done(struct ib_cq *cq, struct ib_wc *wc);
61 static void isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc);
62 static void isert_unmap_tx_desc(struct iser_tx_desc *tx_desc,
63 				struct ib_device *ib_dev);
64 
65 static int isert_sg_tablesize_set(const char *val, const struct kernel_param *kp)
66 {
67 	int n = 0, ret;
68 
69 	ret = kstrtoint(val, 10, &n);
70 	if (ret != 0 || n < ISCSI_ISER_MIN_SG_TABLESIZE ||
71 	    n > ISCSI_ISER_MAX_SG_TABLESIZE)
72 		return -EINVAL;
73 
74 	return param_set_int(val, kp);
75 }
76 
77 static inline bool
78 isert_prot_cmd(struct isert_conn *conn, struct se_cmd *cmd)
79 {
80 	return (conn->pi_support &&
81 		cmd->prot_op != TARGET_PROT_NORMAL);
82 }
83 
84 static void
85 isert_qp_event_callback(struct ib_event *e, void *context)
86 {
87 	struct isert_conn *isert_conn = context;
88 
89 	isert_err("%s (%d): conn %p\n",
90 		  ib_event_msg(e->event), e->event, isert_conn);
91 
92 	switch (e->event) {
93 	case IB_EVENT_COMM_EST:
94 		rdma_notify(isert_conn->cm_id, IB_EVENT_COMM_EST);
95 		break;
96 	default:
97 		break;
98 	}
99 }
100 
101 static struct ib_qp *
102 isert_create_qp(struct isert_conn *isert_conn,
103 		struct rdma_cm_id *cma_id)
104 {
105 	u32 cq_size = ISERT_QP_MAX_REQ_DTOS + ISERT_QP_MAX_RECV_DTOS + 2;
106 	struct isert_device *device = isert_conn->device;
107 	struct ib_device *ib_dev = device->ib_device;
108 	struct ib_qp_init_attr attr;
109 	int ret, factor;
110 
111 	isert_conn->cq = ib_cq_pool_get(ib_dev, cq_size, -1, IB_POLL_WORKQUEUE);
112 	if (IS_ERR(isert_conn->cq)) {
113 		isert_err("Unable to allocate cq\n");
114 		ret = PTR_ERR(isert_conn->cq);
115 		return ERR_PTR(ret);
116 	}
117 	isert_conn->cq_size = cq_size;
118 
119 	memset(&attr, 0, sizeof(struct ib_qp_init_attr));
120 	attr.event_handler = isert_qp_event_callback;
121 	attr.qp_context = isert_conn;
122 	attr.send_cq = isert_conn->cq;
123 	attr.recv_cq = isert_conn->cq;
124 	attr.cap.max_send_wr = ISERT_QP_MAX_REQ_DTOS + 1;
125 	attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS + 1;
126 	factor = rdma_rw_mr_factor(device->ib_device, cma_id->port_num,
127 				   isert_sg_tablesize);
128 	attr.cap.max_rdma_ctxs = ISCSI_DEF_XMIT_CMDS_MAX * factor;
129 	attr.cap.max_send_sge = device->ib_device->attrs.max_send_sge;
130 	attr.cap.max_recv_sge = 1;
131 	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
132 	attr.qp_type = IB_QPT_RC;
133 	if (device->pi_capable)
134 		attr.create_flags |= IB_QP_CREATE_INTEGRITY_EN;
135 
136 	ret = rdma_create_qp(cma_id, device->pd, &attr);
137 	if (ret) {
138 		isert_err("rdma_create_qp failed for cma_id %d\n", ret);
139 		ib_cq_pool_put(isert_conn->cq, isert_conn->cq_size);
140 
141 		return ERR_PTR(ret);
142 	}
143 
144 	return cma_id->qp;
145 }
146 
147 static int
148 isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
149 {
150 	struct isert_device *device = isert_conn->device;
151 	struct ib_device *ib_dev = device->ib_device;
152 	struct iser_rx_desc *rx_desc;
153 	struct ib_sge *rx_sg;
154 	u64 dma_addr;
155 	int i, j;
156 
157 	isert_conn->rx_descs = kzalloc_objs(struct iser_rx_desc,
158 					    ISERT_QP_MAX_RECV_DTOS);
159 	if (!isert_conn->rx_descs)
160 		return -ENOMEM;
161 
162 	rx_desc = isert_conn->rx_descs;
163 
164 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
165 		dma_addr = ib_dma_map_single(ib_dev, rx_desc->buf,
166 					ISER_RX_SIZE, DMA_FROM_DEVICE);
167 		if (ib_dma_mapping_error(ib_dev, dma_addr))
168 			goto dma_map_fail;
169 
170 		rx_desc->dma_addr = dma_addr;
171 
172 		rx_sg = &rx_desc->rx_sg;
173 		rx_sg->addr = rx_desc->dma_addr + isert_get_hdr_offset(rx_desc);
174 		rx_sg->length = ISER_RX_PAYLOAD_SIZE;
175 		rx_sg->lkey = device->pd->local_dma_lkey;
176 		rx_desc->rx_cqe.done = isert_recv_done;
177 	}
178 
179 	return 0;
180 
181 dma_map_fail:
182 	rx_desc = isert_conn->rx_descs;
183 	for (j = 0; j < i; j++, rx_desc++) {
184 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
185 				    ISER_RX_SIZE, DMA_FROM_DEVICE);
186 	}
187 	kfree(isert_conn->rx_descs);
188 	isert_conn->rx_descs = NULL;
189 	isert_err("conn %p failed to allocate rx descriptors\n", isert_conn);
190 	return -ENOMEM;
191 }
192 
193 static void
194 isert_free_rx_descriptors(struct isert_conn *isert_conn)
195 {
196 	struct ib_device *ib_dev = isert_conn->device->ib_device;
197 	struct iser_rx_desc *rx_desc;
198 	int i;
199 
200 	if (!isert_conn->rx_descs)
201 		return;
202 
203 	rx_desc = isert_conn->rx_descs;
204 	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
205 		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
206 				    ISER_RX_SIZE, DMA_FROM_DEVICE);
207 	}
208 
209 	kfree(isert_conn->rx_descs);
210 	isert_conn->rx_descs = NULL;
211 }
212 
213 static int
214 isert_create_device_ib_res(struct isert_device *device)
215 {
216 	struct ib_device *ib_dev = device->ib_device;
217 	int ret;
218 
219 	isert_dbg("devattr->max_send_sge: %u devattr->max_recv_sge %u\n",
220 		  ib_dev->attrs.max_send_sge, ib_dev->attrs.max_recv_sge);
221 	isert_dbg("devattr->max_sge_rd: %u\n", ib_dev->attrs.max_sge_rd);
222 
223 	device->pd = ib_alloc_pd(ib_dev, 0);
224 	if (IS_ERR(device->pd)) {
225 		ret = PTR_ERR(device->pd);
226 		isert_err("failed to allocate pd, device %p, ret=%d\n",
227 			  device, ret);
228 		return ret;
229 	}
230 
231 	/* Check signature cap */
232 	if (ib_dev->attrs.kernel_cap_flags & IBK_INTEGRITY_HANDOVER)
233 		device->pi_capable = true;
234 	else
235 		device->pi_capable = false;
236 
237 	return 0;
238 }
239 
240 static void
241 isert_free_device_ib_res(struct isert_device *device)
242 {
243 	isert_info("device %p\n", device);
244 
245 	ib_dealloc_pd(device->pd);
246 }
247 
248 static void
249 isert_device_put(struct isert_device *device)
250 {
251 	mutex_lock(&device_list_mutex);
252 	device->refcount--;
253 	isert_info("device %p refcount %d\n", device, device->refcount);
254 	if (!device->refcount) {
255 		isert_free_device_ib_res(device);
256 		list_del(&device->dev_node);
257 		kfree(device);
258 	}
259 	mutex_unlock(&device_list_mutex);
260 }
261 
262 static struct isert_device *
263 isert_device_get(struct rdma_cm_id *cma_id)
264 {
265 	struct isert_device *device;
266 	int ret;
267 
268 	mutex_lock(&device_list_mutex);
269 	list_for_each_entry(device, &device_list, dev_node) {
270 		if (device->ib_device->node_guid == cma_id->device->node_guid) {
271 			device->refcount++;
272 			isert_info("Found iser device %p refcount %d\n",
273 				   device, device->refcount);
274 			mutex_unlock(&device_list_mutex);
275 			return device;
276 		}
277 	}
278 
279 	device = kzalloc_obj(struct isert_device);
280 	if (!device) {
281 		mutex_unlock(&device_list_mutex);
282 		return ERR_PTR(-ENOMEM);
283 	}
284 
285 	INIT_LIST_HEAD(&device->dev_node);
286 
287 	device->ib_device = cma_id->device;
288 	ret = isert_create_device_ib_res(device);
289 	if (ret) {
290 		kfree(device);
291 		mutex_unlock(&device_list_mutex);
292 		return ERR_PTR(ret);
293 	}
294 
295 	device->refcount++;
296 	list_add_tail(&device->dev_node, &device_list);
297 	isert_info("Created a new iser device %p refcount %d\n",
298 		   device, device->refcount);
299 	mutex_unlock(&device_list_mutex);
300 
301 	return device;
302 }
303 
304 static void
305 isert_init_conn(struct isert_conn *isert_conn)
306 {
307 	isert_conn->state = ISER_CONN_INIT;
308 	INIT_LIST_HEAD(&isert_conn->node);
309 	init_completion(&isert_conn->login_comp);
310 	init_completion(&isert_conn->login_req_comp);
311 	init_waitqueue_head(&isert_conn->rem_wait);
312 	kref_init(&isert_conn->kref);
313 	mutex_init(&isert_conn->mutex);
314 	INIT_WORK(&isert_conn->release_work, isert_release_work);
315 }
316 
317 static void
318 isert_free_login_buf(struct isert_conn *isert_conn)
319 {
320 	struct ib_device *ib_dev = isert_conn->device->ib_device;
321 
322 	ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
323 			    ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
324 	kfree(isert_conn->login_rsp_buf);
325 
326 	ib_dma_unmap_single(ib_dev, isert_conn->login_desc->dma_addr,
327 			    ISER_RX_SIZE, DMA_FROM_DEVICE);
328 	kfree(isert_conn->login_desc);
329 }
330 
331 static int
332 isert_alloc_login_buf(struct isert_conn *isert_conn,
333 		      struct ib_device *ib_dev)
334 {
335 	int ret;
336 
337 	isert_conn->login_desc = kzalloc_obj(*isert_conn->login_desc);
338 	if (!isert_conn->login_desc)
339 		return -ENOMEM;
340 
341 	isert_conn->login_desc->dma_addr = ib_dma_map_single(ib_dev,
342 				isert_conn->login_desc->buf,
343 				ISER_RX_SIZE, DMA_FROM_DEVICE);
344 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_desc->dma_addr);
345 	if (ret) {
346 		isert_err("login_desc dma mapping error: %d\n", ret);
347 		isert_conn->login_desc->dma_addr = 0;
348 		goto out_free_login_desc;
349 	}
350 
351 	isert_conn->login_rsp_buf = kzalloc(ISER_RX_PAYLOAD_SIZE, GFP_KERNEL);
352 	if (!isert_conn->login_rsp_buf) {
353 		ret = -ENOMEM;
354 		goto out_unmap_login_desc;
355 	}
356 
357 	isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
358 					isert_conn->login_rsp_buf,
359 					ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
360 	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
361 	if (ret) {
362 		isert_err("login_rsp_dma mapping error: %d\n", ret);
363 		isert_conn->login_rsp_dma = 0;
364 		goto out_free_login_rsp_buf;
365 	}
366 
367 	return 0;
368 
369 out_free_login_rsp_buf:
370 	kfree(isert_conn->login_rsp_buf);
371 out_unmap_login_desc:
372 	ib_dma_unmap_single(ib_dev, isert_conn->login_desc->dma_addr,
373 			    ISER_RX_SIZE, DMA_FROM_DEVICE);
374 out_free_login_desc:
375 	kfree(isert_conn->login_desc);
376 	return ret;
377 }
378 
379 static void
380 isert_set_nego_params(struct isert_conn *isert_conn,
381 		      struct rdma_conn_param *param)
382 {
383 	struct ib_device_attr *attr = &isert_conn->device->ib_device->attrs;
384 
385 	/* Set max inflight RDMA READ requests */
386 	isert_conn->initiator_depth = min(param->initiator_depth, attr->max_qp_init_rd_atom);
387 	isert_dbg("Using initiator_depth: %u\n", isert_conn->initiator_depth);
388 
389 	if (param->private_data) {
390 		u8 flags = *(u8 *)param->private_data;
391 
392 		/*
393 		 * use remote invalidation if the both initiator
394 		 * and the HCA support it
395 		 */
396 		isert_conn->snd_w_inv = !(flags & ISER_SEND_W_INV_NOT_SUP) &&
397 					  (attr->device_cap_flags &
398 					   IB_DEVICE_MEM_MGT_EXTENSIONS);
399 		if (isert_conn->snd_w_inv)
400 			isert_info("Using remote invalidation\n");
401 	}
402 }
403 
404 static void
405 isert_destroy_qp(struct isert_conn *isert_conn)
406 {
407 	ib_destroy_qp(isert_conn->qp);
408 	ib_cq_pool_put(isert_conn->cq, isert_conn->cq_size);
409 }
410 
411 static int
412 isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
413 {
414 	struct isert_np *isert_np = cma_id->context;
415 	struct iscsi_np *np = isert_np->np;
416 	struct isert_conn *isert_conn;
417 	struct isert_device *device;
418 	int ret = 0;
419 
420 	spin_lock_bh(&np->np_thread_lock);
421 	if (!np->enabled) {
422 		spin_unlock_bh(&np->np_thread_lock);
423 		isert_dbg("iscsi_np is not enabled, reject connect request\n");
424 		return rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
425 	}
426 	spin_unlock_bh(&np->np_thread_lock);
427 
428 	isert_dbg("cma_id: %p, portal: %p\n",
429 		 cma_id, cma_id->context);
430 
431 	isert_conn = kzalloc_obj(struct isert_conn);
432 	if (!isert_conn)
433 		return -ENOMEM;
434 
435 	isert_init_conn(isert_conn);
436 	isert_conn->cm_id = cma_id;
437 
438 	device = isert_device_get(cma_id);
439 	if (IS_ERR(device)) {
440 		ret = PTR_ERR(device);
441 		goto out;
442 	}
443 	isert_conn->device = device;
444 
445 	ret = isert_alloc_login_buf(isert_conn, cma_id->device);
446 	if (ret)
447 		goto out_conn_dev;
448 
449 	isert_set_nego_params(isert_conn, &event->param.conn);
450 
451 	isert_conn->qp = isert_create_qp(isert_conn, cma_id);
452 	if (IS_ERR(isert_conn->qp)) {
453 		ret = PTR_ERR(isert_conn->qp);
454 		goto out_rsp_dma_map;
455 	}
456 
457 	ret = isert_login_post_recv(isert_conn);
458 	if (ret)
459 		goto out_destroy_qp;
460 
461 	ret = isert_rdma_accept(isert_conn);
462 	if (ret)
463 		goto out_destroy_qp;
464 
465 	mutex_lock(&isert_np->mutex);
466 	list_add_tail(&isert_conn->node, &isert_np->accepted);
467 	mutex_unlock(&isert_np->mutex);
468 
469 	return 0;
470 
471 out_destroy_qp:
472 	isert_destroy_qp(isert_conn);
473 out_rsp_dma_map:
474 	isert_free_login_buf(isert_conn);
475 out_conn_dev:
476 	isert_device_put(device);
477 out:
478 	kfree(isert_conn);
479 	rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
480 	return ret;
481 }
482 
483 static void
484 isert_connect_release(struct isert_conn *isert_conn)
485 {
486 	struct isert_device *device = isert_conn->device;
487 
488 	isert_dbg("conn %p\n", isert_conn);
489 
490 	BUG_ON(!device);
491 
492 	isert_free_rx_descriptors(isert_conn);
493 	if (isert_conn->cm_id &&
494 	    !isert_conn->dev_removed)
495 		rdma_destroy_id(isert_conn->cm_id);
496 
497 	if (isert_conn->qp)
498 		isert_destroy_qp(isert_conn);
499 
500 	isert_unmap_tx_desc(&isert_conn->login_tx_desc, device->ib_device);
501 
502 	if (isert_conn->login_desc)
503 		isert_free_login_buf(isert_conn);
504 
505 	isert_device_put(device);
506 
507 	if (isert_conn->dev_removed)
508 		wake_up_interruptible(&isert_conn->rem_wait);
509 	else
510 		kfree(isert_conn);
511 }
512 
513 static void
514 isert_connected_handler(struct rdma_cm_id *cma_id)
515 {
516 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
517 	struct isert_np *isert_np = cma_id->context;
518 
519 	isert_info("conn %p\n", isert_conn);
520 
521 	mutex_lock(&isert_conn->mutex);
522 	isert_conn->state = ISER_CONN_UP;
523 	kref_get(&isert_conn->kref);
524 	mutex_unlock(&isert_conn->mutex);
525 
526 	mutex_lock(&isert_np->mutex);
527 	list_move_tail(&isert_conn->node, &isert_np->pending);
528 	mutex_unlock(&isert_np->mutex);
529 
530 	isert_info("np %p: Allow accept_np to continue\n", isert_np);
531 	up(&isert_np->sem);
532 }
533 
534 static void
535 isert_release_kref(struct kref *kref)
536 {
537 	struct isert_conn *isert_conn = container_of(kref,
538 				struct isert_conn, kref);
539 
540 	isert_info("conn %p final kref %s/%d\n", isert_conn, current->comm,
541 		   current->pid);
542 
543 	isert_connect_release(isert_conn);
544 }
545 
546 static void
547 isert_put_conn(struct isert_conn *isert_conn)
548 {
549 	kref_put(&isert_conn->kref, isert_release_kref);
550 }
551 
552 static void
553 isert_handle_unbound_conn(struct isert_conn *isert_conn)
554 {
555 	struct isert_np *isert_np = isert_conn->cm_id->context;
556 
557 	mutex_lock(&isert_np->mutex);
558 	if (!list_empty(&isert_conn->node)) {
559 		/*
560 		 * This means iscsi doesn't know this connection
561 		 * so schedule a cleanup ourselves
562 		 */
563 		list_del_init(&isert_conn->node);
564 		isert_put_conn(isert_conn);
565 		queue_work(isert_release_wq, &isert_conn->release_work);
566 	}
567 	mutex_unlock(&isert_np->mutex);
568 }
569 
570 /**
571  * isert_conn_terminate() - Initiate connection termination
572  * @isert_conn: isert connection struct
573  *
574  * Notes:
575  * In case the connection state is BOUND, move state
576  * to TEMINATING and start teardown sequence (rdma_disconnect).
577  * In case the connection state is UP, complete flush as well.
578  *
579  * This routine must be called with mutex held. Thus it is
580  * safe to call multiple times.
581  */
582 static void
583 isert_conn_terminate(struct isert_conn *isert_conn)
584 {
585 	int err;
586 
587 	if (isert_conn->state >= ISER_CONN_TERMINATING)
588 		return;
589 
590 	isert_info("Terminating conn %p state %d\n",
591 		   isert_conn, isert_conn->state);
592 	isert_conn->state = ISER_CONN_TERMINATING;
593 	err = rdma_disconnect(isert_conn->cm_id);
594 	if (err)
595 		isert_warn("Failed rdma_disconnect isert_conn %p\n",
596 			   isert_conn);
597 }
598 
599 static int
600 isert_np_cma_handler(struct isert_np *isert_np,
601 		     enum rdma_cm_event_type event)
602 {
603 	isert_dbg("%s (%d): isert np %p\n",
604 		  rdma_event_msg(event), event, isert_np);
605 
606 	switch (event) {
607 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
608 		isert_np->cm_id = NULL;
609 		break;
610 	case RDMA_CM_EVENT_ADDR_CHANGE:
611 		isert_np->cm_id = isert_setup_id(isert_np);
612 		if (IS_ERR(isert_np->cm_id)) {
613 			isert_err("isert np %p setup id failed: %ld\n",
614 				  isert_np, PTR_ERR(isert_np->cm_id));
615 			isert_np->cm_id = NULL;
616 		}
617 		break;
618 	default:
619 		isert_err("isert np %p Unexpected event %d\n",
620 			  isert_np, event);
621 	}
622 
623 	return -1;
624 }
625 
626 static int
627 isert_disconnected_handler(struct rdma_cm_id *cma_id,
628 			   enum rdma_cm_event_type event)
629 {
630 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
631 
632 	mutex_lock(&isert_conn->mutex);
633 	switch (isert_conn->state) {
634 	case ISER_CONN_TERMINATING:
635 		break;
636 	case ISER_CONN_UP:
637 		isert_conn_terminate(isert_conn);
638 		ib_drain_qp(isert_conn->qp);
639 		isert_handle_unbound_conn(isert_conn);
640 		break;
641 	case ISER_CONN_BOUND:
642 	case ISER_CONN_FULL_FEATURE: /* FALLTHRU */
643 		iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
644 		break;
645 	default:
646 		isert_warn("conn %p terminating in state %d\n",
647 			   isert_conn, isert_conn->state);
648 	}
649 	mutex_unlock(&isert_conn->mutex);
650 
651 	return 0;
652 }
653 
654 static int
655 isert_connect_error(struct rdma_cm_id *cma_id)
656 {
657 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
658 	struct isert_np *isert_np = cma_id->context;
659 
660 	ib_drain_qp(isert_conn->qp);
661 
662 	mutex_lock(&isert_np->mutex);
663 	list_del_init(&isert_conn->node);
664 	mutex_unlock(&isert_np->mutex);
665 	isert_conn->cm_id = NULL;
666 	isert_put_conn(isert_conn);
667 
668 	return -1;
669 }
670 
671 static int
672 isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
673 {
674 	struct isert_np *isert_np = cma_id->context;
675 	struct isert_conn *isert_conn;
676 	int ret = 0;
677 
678 	isert_info("%s (%d): status %d id %p np %p\n",
679 		   rdma_event_msg(event->event), event->event,
680 		   event->status, cma_id, cma_id->context);
681 
682 	if (isert_np->cm_id == cma_id)
683 		return isert_np_cma_handler(cma_id->context, event->event);
684 
685 	switch (event->event) {
686 	case RDMA_CM_EVENT_CONNECT_REQUEST:
687 		ret = isert_connect_request(cma_id, event);
688 		if (ret)
689 			isert_err("failed handle connect request %d\n", ret);
690 		break;
691 	case RDMA_CM_EVENT_ESTABLISHED:
692 		isert_connected_handler(cma_id);
693 		break;
694 	case RDMA_CM_EVENT_ADDR_CHANGE:
695 	case RDMA_CM_EVENT_DISCONNECTED:
696 	case RDMA_CM_EVENT_TIMEWAIT_EXIT:  /* FALLTHRU */
697 		ret = isert_disconnected_handler(cma_id, event->event);
698 		break;
699 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
700 		isert_conn = cma_id->qp->qp_context;
701 		isert_conn->dev_removed = true;
702 		isert_disconnected_handler(cma_id, event->event);
703 		wait_event_interruptible(isert_conn->rem_wait,
704 					 isert_conn->state == ISER_CONN_DOWN);
705 		kfree(isert_conn);
706 		/*
707 		 * return non-zero from the callback to destroy
708 		 * the rdma cm id
709 		 */
710 		return 1;
711 	case RDMA_CM_EVENT_REJECTED:
712 		isert_info("Connection rejected: %s\n",
713 			   rdma_reject_msg(cma_id, event->status));
714 		fallthrough;
715 	case RDMA_CM_EVENT_UNREACHABLE:
716 	case RDMA_CM_EVENT_CONNECT_ERROR:
717 		ret = isert_connect_error(cma_id);
718 		break;
719 	default:
720 		isert_err("Unhandled RDMA CMA event: %d\n", event->event);
721 		break;
722 	}
723 
724 	return ret;
725 }
726 
727 static int
728 isert_post_recvm(struct isert_conn *isert_conn, u32 count)
729 {
730 	struct ib_recv_wr *rx_wr;
731 	int i, ret;
732 	struct iser_rx_desc *rx_desc;
733 
734 	for (rx_wr = isert_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
735 		rx_desc = &isert_conn->rx_descs[i];
736 
737 		rx_wr->wr_cqe = &rx_desc->rx_cqe;
738 		rx_wr->sg_list = &rx_desc->rx_sg;
739 		rx_wr->num_sge = 1;
740 		rx_wr->next = rx_wr + 1;
741 		rx_desc->in_use = false;
742 	}
743 	rx_wr--;
744 	rx_wr->next = NULL; /* mark end of work requests list */
745 
746 	ret = ib_post_recv(isert_conn->qp, isert_conn->rx_wr, NULL);
747 	if (ret)
748 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
749 
750 	return ret;
751 }
752 
753 static int
754 isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
755 {
756 	struct ib_recv_wr rx_wr;
757 	int ret;
758 
759 	if (!rx_desc->in_use) {
760 		/*
761 		 * if the descriptor is not in-use we already reposted it
762 		 * for recv, so just silently return
763 		 */
764 		return 0;
765 	}
766 
767 	rx_desc->in_use = false;
768 	rx_wr.wr_cqe = &rx_desc->rx_cqe;
769 	rx_wr.sg_list = &rx_desc->rx_sg;
770 	rx_wr.num_sge = 1;
771 	rx_wr.next = NULL;
772 
773 	ret = ib_post_recv(isert_conn->qp, &rx_wr, NULL);
774 	if (ret)
775 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
776 
777 	return ret;
778 }
779 
780 static int
781 isert_login_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
782 {
783 	struct ib_device *ib_dev = isert_conn->cm_id->device;
784 	struct ib_send_wr send_wr;
785 	int ret;
786 
787 	ib_dma_sync_single_for_device(ib_dev, tx_desc->dma_addr,
788 				      ISER_HEADERS_LEN, DMA_TO_DEVICE);
789 
790 	tx_desc->tx_cqe.done = isert_login_send_done;
791 
792 	send_wr.next	= NULL;
793 	send_wr.wr_cqe	= &tx_desc->tx_cqe;
794 	send_wr.sg_list	= tx_desc->tx_sg;
795 	send_wr.num_sge	= tx_desc->num_sge;
796 	send_wr.opcode	= IB_WR_SEND;
797 	send_wr.send_flags = IB_SEND_SIGNALED;
798 
799 	ret = ib_post_send(isert_conn->qp, &send_wr, NULL);
800 	if (ret)
801 		isert_err("ib_post_send() failed, ret: %d\n", ret);
802 
803 	return ret;
804 }
805 
806 static void
807 __isert_create_send_desc(struct isert_device *device,
808 			 struct iser_tx_desc *tx_desc)
809 {
810 
811 	memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl));
812 	tx_desc->iser_header.flags = ISCSI_CTRL;
813 
814 	tx_desc->num_sge = 1;
815 
816 	if (tx_desc->tx_sg[0].lkey != device->pd->local_dma_lkey) {
817 		tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
818 		isert_dbg("tx_desc %p lkey mismatch, fixing\n", tx_desc);
819 	}
820 }
821 
822 static void
823 isert_create_send_desc(struct isert_conn *isert_conn,
824 		       struct isert_cmd *isert_cmd,
825 		       struct iser_tx_desc *tx_desc)
826 {
827 	struct isert_device *device = isert_conn->device;
828 	struct ib_device *ib_dev = device->ib_device;
829 
830 	ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr,
831 				   ISER_HEADERS_LEN, DMA_TO_DEVICE);
832 
833 	__isert_create_send_desc(device, tx_desc);
834 }
835 
836 static int
837 isert_init_tx_hdrs(struct isert_conn *isert_conn,
838 		   struct iser_tx_desc *tx_desc)
839 {
840 	struct isert_device *device = isert_conn->device;
841 	struct ib_device *ib_dev = device->ib_device;
842 	u64 dma_addr;
843 
844 	dma_addr = ib_dma_map_single(ib_dev, (void *)tx_desc,
845 			ISER_HEADERS_LEN, DMA_TO_DEVICE);
846 	if (ib_dma_mapping_error(ib_dev, dma_addr)) {
847 		isert_err("ib_dma_mapping_error() failed\n");
848 		return -ENOMEM;
849 	}
850 
851 	tx_desc->dma_addr = dma_addr;
852 	tx_desc->tx_sg[0].addr	= tx_desc->dma_addr;
853 	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
854 	tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
855 
856 	isert_dbg("Setup tx_sg[0].addr: 0x%llx length: %u lkey: 0x%x\n",
857 		  tx_desc->tx_sg[0].addr, tx_desc->tx_sg[0].length,
858 		  tx_desc->tx_sg[0].lkey);
859 
860 	return 0;
861 }
862 
863 static void
864 isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
865 		   struct ib_send_wr *send_wr)
866 {
867 	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
868 
869 	tx_desc->tx_cqe.done = isert_send_done;
870 	send_wr->wr_cqe = &tx_desc->tx_cqe;
871 
872 	if (isert_conn->snd_w_inv && isert_cmd->inv_rkey) {
873 		send_wr->opcode  = IB_WR_SEND_WITH_INV;
874 		send_wr->ex.invalidate_rkey = isert_cmd->inv_rkey;
875 	} else {
876 		send_wr->opcode = IB_WR_SEND;
877 	}
878 
879 	send_wr->sg_list = &tx_desc->tx_sg[0];
880 	send_wr->num_sge = isert_cmd->tx_desc.num_sge;
881 	send_wr->send_flags = IB_SEND_SIGNALED;
882 }
883 
884 static int
885 isert_login_post_recv(struct isert_conn *isert_conn)
886 {
887 	struct ib_recv_wr rx_wr;
888 	struct ib_sge sge;
889 	int ret;
890 
891 	memset(&sge, 0, sizeof(struct ib_sge));
892 	sge.addr = isert_conn->login_desc->dma_addr +
893 		isert_get_hdr_offset(isert_conn->login_desc);
894 	sge.length = ISER_RX_PAYLOAD_SIZE;
895 	sge.lkey = isert_conn->device->pd->local_dma_lkey;
896 
897 	isert_dbg("Setup sge: addr: %llx length: %d 0x%08x\n",
898 		sge.addr, sge.length, sge.lkey);
899 
900 	isert_conn->login_desc->rx_cqe.done = isert_login_recv_done;
901 
902 	memset(&rx_wr, 0, sizeof(struct ib_recv_wr));
903 	rx_wr.wr_cqe = &isert_conn->login_desc->rx_cqe;
904 	rx_wr.sg_list = &sge;
905 	rx_wr.num_sge = 1;
906 
907 	ret = ib_post_recv(isert_conn->qp, &rx_wr, NULL);
908 	if (ret)
909 		isert_err("ib_post_recv() failed: %d\n", ret);
910 
911 	return ret;
912 }
913 
914 static int
915 isert_put_login_tx(struct iscsit_conn *conn, struct iscsi_login *login,
916 		   u32 length)
917 {
918 	struct isert_conn *isert_conn = conn->context;
919 	struct isert_device *device = isert_conn->device;
920 	struct ib_device *ib_dev = device->ib_device;
921 	struct iser_tx_desc *tx_desc = &isert_conn->login_tx_desc;
922 	int ret;
923 
924 	__isert_create_send_desc(device, tx_desc);
925 
926 	memcpy(&tx_desc->iscsi_header, &login->rsp[0],
927 	       sizeof(struct iscsi_hdr));
928 
929 	isert_init_tx_hdrs(isert_conn, tx_desc);
930 
931 	if (length > 0) {
932 		struct ib_sge *tx_dsg = &tx_desc->tx_sg[1];
933 
934 		ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_rsp_dma,
935 					   length, DMA_TO_DEVICE);
936 
937 		memcpy(isert_conn->login_rsp_buf, login->rsp_buf, length);
938 
939 		ib_dma_sync_single_for_device(ib_dev, isert_conn->login_rsp_dma,
940 					      length, DMA_TO_DEVICE);
941 
942 		tx_dsg->addr	= isert_conn->login_rsp_dma;
943 		tx_dsg->length	= length;
944 		tx_dsg->lkey	= isert_conn->device->pd->local_dma_lkey;
945 		tx_desc->num_sge = 2;
946 	}
947 	if (!login->login_failed) {
948 		if (login->login_complete) {
949 			/* Posted and sent from isert_get_rx_pdu(). */
950 			isert_conn->login_rsp_pending = true;
951 			return 0;
952 		}
953 
954 		ret = isert_login_post_recv(isert_conn);
955 		if (ret)
956 			return ret;
957 	}
958 
959 	ret = isert_login_post_send(isert_conn, tx_desc);
960 	if (ret)
961 		return ret;
962 
963 	return 0;
964 }
965 
966 static int
967 isert_check_login_req(struct isert_conn *isert_conn)
968 {
969 	struct iscsi_hdr *hdr = isert_get_iscsi_hdr(isert_conn->login_desc);
970 	u32 dlength = ntoh24(hdr->dlength);
971 
972 	if (unlikely(dlength > (u32)isert_conn->login_req_len)) {
973 		isert_dbg("login PDU declares %u data bytes but only %d were received\n",
974 			  dlength, isert_conn->login_req_len);
975 		return -EINVAL;
976 	}
977 
978 	return 0;
979 }
980 
981 static void
982 isert_rx_login_req(struct isert_conn *isert_conn)
983 {
984 	struct iser_rx_desc *rx_desc = isert_conn->login_desc;
985 	int rx_buflen = isert_conn->login_req_len;
986 	struct iscsit_conn *conn = isert_conn->conn;
987 	struct iscsi_login *login = conn->conn_login;
988 	int size;
989 
990 	isert_info("conn %p\n", isert_conn);
991 
992 	WARN_ON_ONCE(!login);
993 
994 	if (login->first_request) {
995 		struct iscsi_login_req *login_req =
996 			(struct iscsi_login_req *)isert_get_iscsi_hdr(rx_desc);
997 		/*
998 		 * Setup the initial iscsi_login values from the leading
999 		 * login request PDU.
1000 		 */
1001 		login->leading_connection = (!login_req->tsih) ? 1 : 0;
1002 		login->current_stage = ISCSI_LOGIN_CURRENT_STAGE(
1003 				login_req->flags);
1004 		login->version_min	= login_req->min_version;
1005 		login->version_max	= login_req->max_version;
1006 		memcpy(login->isid, login_req->isid, 6);
1007 		login->cmd_sn		= be32_to_cpu(login_req->cmdsn);
1008 		login->init_task_tag	= login_req->itt;
1009 		login->initial_exp_statsn = be32_to_cpu(login_req->exp_statsn);
1010 		login->cid		= be16_to_cpu(login_req->cid);
1011 		login->tsih		= be16_to_cpu(login_req->tsih);
1012 	}
1013 
1014 	memcpy(&login->req[0], isert_get_iscsi_hdr(rx_desc), ISCSI_HDR_LEN);
1015 
1016 	size = min(rx_buflen, MAX_KEY_VALUE_PAIRS);
1017 	isert_dbg("Using login payload size: %d, rx_buflen: %d "
1018 		  "MAX_KEY_VALUE_PAIRS: %d\n", size, rx_buflen,
1019 		  MAX_KEY_VALUE_PAIRS);
1020 	memcpy(login->req_buf, isert_get_data(rx_desc), size);
1021 
1022 	if (login->first_request) {
1023 		complete(&isert_conn->login_comp);
1024 		return;
1025 	}
1026 	queue_delayed_work(isert_login_wq, &conn->login_work, 0);
1027 }
1028 
1029 static struct iscsit_cmd
1030 *isert_allocate_cmd(struct iscsit_conn *conn, struct iser_rx_desc *rx_desc)
1031 {
1032 	struct isert_conn *isert_conn = conn->context;
1033 	struct isert_cmd *isert_cmd;
1034 	struct iscsit_cmd *cmd;
1035 
1036 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
1037 	if (!cmd) {
1038 		isert_err("Unable to allocate iscsit_cmd + isert_cmd\n");
1039 		return NULL;
1040 	}
1041 	isert_cmd = iscsit_priv_cmd(cmd);
1042 	isert_cmd->conn = isert_conn;
1043 	isert_cmd->iscsit_cmd = cmd;
1044 	isert_cmd->rx_desc = rx_desc;
1045 
1046 	return cmd;
1047 }
1048 
1049 static int
1050 isert_handle_scsi_cmd(struct isert_conn *isert_conn,
1051 		      struct isert_cmd *isert_cmd, struct iscsit_cmd *cmd,
1052 		      struct iser_rx_desc *rx_desc, unsigned char *buf)
1053 {
1054 	struct iscsit_conn *conn = isert_conn->conn;
1055 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1056 	int imm_data, imm_data_len, unsol_data, sg_nents, rc;
1057 	bool dump_payload = false;
1058 	unsigned int data_len;
1059 
1060 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1061 	if (rc < 0)
1062 		return rc;
1063 
1064 	imm_data = cmd->immediate_data;
1065 	imm_data_len = cmd->first_burst_len;
1066 	unsol_data = cmd->unsolicited_data;
1067 	data_len = cmd->se_cmd.data_length;
1068 
1069 	if (imm_data && imm_data_len == data_len)
1070 		cmd->se_cmd.se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
1071 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1072 	if (rc < 0) {
1073 		return 0;
1074 	} else if (rc > 0) {
1075 		dump_payload = true;
1076 		goto sequence_cmd;
1077 	}
1078 
1079 	if (!imm_data)
1080 		return 0;
1081 
1082 	if (imm_data_len != data_len) {
1083 		sg_nents = max(1UL, DIV_ROUND_UP(imm_data_len, PAGE_SIZE));
1084 		sg_copy_from_buffer(cmd->se_cmd.t_data_sg, sg_nents,
1085 				    isert_get_data(rx_desc), imm_data_len);
1086 		isert_dbg("Copy Immediate sg_nents: %u imm_data_len: %d\n",
1087 			  sg_nents, imm_data_len);
1088 	} else {
1089 		sg_init_table(&isert_cmd->sg, 1);
1090 		cmd->se_cmd.t_data_sg = &isert_cmd->sg;
1091 		cmd->se_cmd.t_data_nents = 1;
1092 		sg_set_buf(&isert_cmd->sg, isert_get_data(rx_desc),
1093 				imm_data_len);
1094 		isert_dbg("Transfer Immediate imm_data_len: %d\n",
1095 			  imm_data_len);
1096 	}
1097 
1098 	cmd->write_data_done += imm_data_len;
1099 
1100 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
1101 		spin_lock_bh(&cmd->istate_lock);
1102 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1103 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1104 		spin_unlock_bh(&cmd->istate_lock);
1105 	}
1106 
1107 sequence_cmd:
1108 	rc = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1109 
1110 	if (!rc && !dump_payload && unsol_data)
1111 		iscsit_set_unsolicited_dataout(cmd);
1112 	else if (dump_payload && imm_data)
1113 		target_put_sess_cmd(&cmd->se_cmd);
1114 
1115 	return 0;
1116 }
1117 
1118 static int
1119 isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
1120 			   struct iser_rx_desc *rx_desc, unsigned char *buf)
1121 {
1122 	struct scatterlist *sg_start;
1123 	struct iscsit_conn *conn = isert_conn->conn;
1124 	struct iscsit_cmd *cmd = NULL;
1125 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1126 	u32 unsol_data_len = ntoh24(hdr->dlength);
1127 	int rc, sg_nents, sg_off, page_off;
1128 
1129 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1130 	if (rc < 0)
1131 		return rc;
1132 	else if (!cmd)
1133 		return 0;
1134 	/*
1135 	 * FIXME: Unexpected unsolicited_data out
1136 	 */
1137 	if (!cmd->unsolicited_data) {
1138 		isert_err("Received unexpected solicited data payload\n");
1139 		dump_stack();
1140 		return -1;
1141 	}
1142 
1143 	isert_dbg("Unsolicited DataOut unsol_data_len: %u, "
1144 		  "write_data_done: %u, data_length: %u\n",
1145 		  unsol_data_len,  cmd->write_data_done,
1146 		  cmd->se_cmd.data_length);
1147 
1148 	sg_off = cmd->write_data_done / PAGE_SIZE;
1149 	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
1150 	sg_nents = max(1UL, DIV_ROUND_UP(unsol_data_len, PAGE_SIZE));
1151 	page_off = cmd->write_data_done % PAGE_SIZE;
1152 	/*
1153 	 * FIXME: Non page-aligned unsolicited_data out
1154 	 */
1155 	if (page_off) {
1156 		isert_err("unexpected non-page aligned data payload\n");
1157 		dump_stack();
1158 		return -1;
1159 	}
1160 	isert_dbg("Copying DataOut: sg_start: %p, sg_off: %u "
1161 		  "sg_nents: %u from %p %u\n", sg_start, sg_off,
1162 		  sg_nents, isert_get_data(rx_desc), unsol_data_len);
1163 
1164 	sg_copy_from_buffer(sg_start, sg_nents, isert_get_data(rx_desc),
1165 			    unsol_data_len);
1166 
1167 	rc = iscsit_check_dataout_payload(cmd, hdr, false);
1168 	if (rc < 0)
1169 		return rc;
1170 
1171 	/*
1172 	 * multiple data-outs on the same command can arrive -
1173 	 * so post the buffer before hand
1174 	 */
1175 	return isert_post_recv(isert_conn, rx_desc);
1176 }
1177 
1178 static int
1179 isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1180 		     struct iscsit_cmd *cmd, struct iser_rx_desc *rx_desc,
1181 		     unsigned char *buf)
1182 {
1183 	struct iscsit_conn *conn = isert_conn->conn;
1184 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1185 	int rc;
1186 
1187 	rc = iscsit_setup_nop_out(conn, cmd, hdr);
1188 	if (rc < 0)
1189 		return rc;
1190 	/*
1191 	 * FIXME: Add support for NOPOUT payload using unsolicited RDMA payload
1192 	 */
1193 
1194 	return iscsit_process_nop_out(conn, cmd, hdr);
1195 }
1196 
1197 static int
1198 isert_handle_text_cmd(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
1199 		      struct iscsit_cmd *cmd, struct iser_rx_desc *rx_desc,
1200 		      struct iscsi_text *hdr)
1201 {
1202 	struct iscsit_conn *conn = isert_conn->conn;
1203 	u32 payload_length = ntoh24(hdr->dlength);
1204 	int rc;
1205 	unsigned char *text_in = NULL;
1206 
1207 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
1208 	if (rc < 0)
1209 		return rc;
1210 
1211 	if (payload_length) {
1212 		text_in = kzalloc(payload_length, GFP_KERNEL);
1213 		if (!text_in)
1214 			return -ENOMEM;
1215 	}
1216 	cmd->text_in_ptr = text_in;
1217 
1218 	memcpy(cmd->text_in_ptr, isert_get_data(rx_desc), payload_length);
1219 
1220 	return iscsit_process_text_cmd(conn, cmd, hdr);
1221 }
1222 
1223 static int
1224 isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
1225 		uint32_t read_stag, uint64_t read_va,
1226 		uint32_t write_stag, uint64_t write_va)
1227 {
1228 	struct iscsi_hdr *hdr = isert_get_iscsi_hdr(rx_desc);
1229 	struct iscsit_conn *conn = isert_conn->conn;
1230 	struct iscsit_cmd *cmd;
1231 	struct isert_cmd *isert_cmd;
1232 	int ret = -EINVAL;
1233 	u8 opcode = (hdr->opcode & ISCSI_OPCODE_MASK);
1234 
1235 	if (conn->sess->sess_ops->SessionType &&
1236 	   (!(opcode & ISCSI_OP_TEXT) || !(opcode & ISCSI_OP_LOGOUT))) {
1237 		isert_err("Got illegal opcode: 0x%02x in SessionType=Discovery,"
1238 			  " ignoring\n", opcode);
1239 		return 0;
1240 	}
1241 
1242 	switch (opcode) {
1243 	case ISCSI_OP_SCSI_CMD:
1244 		cmd = isert_allocate_cmd(conn, rx_desc);
1245 		if (!cmd)
1246 			break;
1247 
1248 		isert_cmd = iscsit_priv_cmd(cmd);
1249 		isert_cmd->read_stag = read_stag;
1250 		isert_cmd->read_va = read_va;
1251 		isert_cmd->write_stag = write_stag;
1252 		isert_cmd->write_va = write_va;
1253 		isert_cmd->inv_rkey = read_stag ? read_stag : write_stag;
1254 
1255 		ret = isert_handle_scsi_cmd(isert_conn, isert_cmd, cmd,
1256 					rx_desc, (unsigned char *)hdr);
1257 		break;
1258 	case ISCSI_OP_NOOP_OUT:
1259 		cmd = isert_allocate_cmd(conn, rx_desc);
1260 		if (!cmd)
1261 			break;
1262 
1263 		isert_cmd = iscsit_priv_cmd(cmd);
1264 		ret = isert_handle_nop_out(isert_conn, isert_cmd, cmd,
1265 					   rx_desc, (unsigned char *)hdr);
1266 		break;
1267 	case ISCSI_OP_SCSI_DATA_OUT:
1268 		ret = isert_handle_iscsi_dataout(isert_conn, rx_desc,
1269 						(unsigned char *)hdr);
1270 		break;
1271 	case ISCSI_OP_SCSI_TMFUNC:
1272 		cmd = isert_allocate_cmd(conn, rx_desc);
1273 		if (!cmd)
1274 			break;
1275 
1276 		ret = iscsit_handle_task_mgt_cmd(conn, cmd,
1277 						(unsigned char *)hdr);
1278 		break;
1279 	case ISCSI_OP_LOGOUT:
1280 		cmd = isert_allocate_cmd(conn, rx_desc);
1281 		if (!cmd)
1282 			break;
1283 
1284 		ret = iscsit_handle_logout_cmd(conn, cmd, (unsigned char *)hdr);
1285 		break;
1286 	case ISCSI_OP_TEXT:
1287 		if (be32_to_cpu(hdr->ttt) != 0xFFFFFFFF)
1288 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
1289 		else
1290 			cmd = isert_allocate_cmd(conn, rx_desc);
1291 
1292 		if (!cmd)
1293 			break;
1294 
1295 		isert_cmd = iscsit_priv_cmd(cmd);
1296 		ret = isert_handle_text_cmd(isert_conn, isert_cmd, cmd,
1297 					    rx_desc, (struct iscsi_text *)hdr);
1298 		break;
1299 	default:
1300 		isert_err("Got unknown iSCSI OpCode: 0x%02x\n", opcode);
1301 		dump_stack();
1302 		break;
1303 	}
1304 
1305 	return ret;
1306 }
1307 
1308 static void
1309 isert_print_wc(struct ib_wc *wc, const char *type)
1310 {
1311 	if (wc->status != IB_WC_WR_FLUSH_ERR)
1312 		isert_err("%s failure: %s (%d) vend_err %x\n", type,
1313 			  ib_wc_status_msg(wc->status), wc->status,
1314 			  wc->vendor_err);
1315 	else
1316 		isert_dbg("%s failure: %s (%d)\n", type,
1317 			  ib_wc_status_msg(wc->status), wc->status);
1318 }
1319 
1320 static void
1321 isert_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1322 {
1323 	struct isert_conn *isert_conn = wc->qp->qp_context;
1324 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1325 	struct iser_rx_desc *rx_desc = cqe_to_rx_desc(wc->wr_cqe);
1326 	struct iscsi_hdr *hdr = isert_get_iscsi_hdr(rx_desc);
1327 	struct iser_ctrl *iser_ctrl = isert_get_iser_hdr(rx_desc);
1328 	uint64_t read_va = 0, write_va = 0;
1329 	uint32_t read_stag = 0, write_stag = 0;
1330 
1331 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1332 		isert_print_wc(wc, "recv");
1333 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1334 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1335 		return;
1336 	}
1337 
1338 	rx_desc->in_use = true;
1339 
1340 	ib_dma_sync_single_for_cpu(ib_dev, rx_desc->dma_addr,
1341 			ISER_RX_SIZE, DMA_FROM_DEVICE);
1342 
1343 	/*
1344 	 * The data segment length declared in the BHS is attacker controlled
1345 	 * and is used further down to read that many bytes out of the fixed
1346 	 * size receive descriptor, so it has to be checked against the number
1347 	 * of bytes that were actually received. Comparing without subtracting
1348 	 * also rejects PDUs shorter than the iSER and iSCSI headers, which
1349 	 * would otherwise be parsed out of stale descriptor contents.
1350 	 */
1351 	if (unlikely(wc->byte_len < ISER_HEADERS_LEN + ntoh24(hdr->dlength))) {
1352 		isert_err("PDU declares %u data bytes but only %u bytes were received\n",
1353 			  ntoh24(hdr->dlength), wc->byte_len);
1354 		iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1355 		return;
1356 	}
1357 
1358 	isert_dbg("DMA: 0x%llx, iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n",
1359 		 rx_desc->dma_addr, hdr->opcode, hdr->itt, hdr->flags,
1360 		 (int)(wc->byte_len - ISER_HEADERS_LEN));
1361 
1362 	switch (iser_ctrl->flags & 0xF0) {
1363 	case ISCSI_CTRL:
1364 		if (iser_ctrl->flags & ISER_RSV) {
1365 			read_stag = be32_to_cpu(iser_ctrl->read_stag);
1366 			read_va = be64_to_cpu(iser_ctrl->read_va);
1367 			isert_dbg("ISER_RSV: read_stag: 0x%x read_va: 0x%llx\n",
1368 				  read_stag, (unsigned long long)read_va);
1369 		}
1370 		if (iser_ctrl->flags & ISER_WSV) {
1371 			write_stag = be32_to_cpu(iser_ctrl->write_stag);
1372 			write_va = be64_to_cpu(iser_ctrl->write_va);
1373 			isert_dbg("ISER_WSV: write_stag: 0x%x write_va: 0x%llx\n",
1374 				  write_stag, (unsigned long long)write_va);
1375 		}
1376 
1377 		isert_dbg("ISER ISCSI_CTRL PDU\n");
1378 		break;
1379 	case ISER_HELLO:
1380 		isert_err("iSER Hello message\n");
1381 		break;
1382 	default:
1383 		isert_warn("Unknown iSER hdr flags: 0x%02x\n", iser_ctrl->flags);
1384 		break;
1385 	}
1386 
1387 	isert_rx_opcode(isert_conn, rx_desc,
1388 			read_stag, read_va, write_stag, write_va);
1389 
1390 	ib_dma_sync_single_for_device(ib_dev, rx_desc->dma_addr,
1391 			ISER_RX_SIZE, DMA_FROM_DEVICE);
1392 }
1393 
1394 static void
1395 isert_login_recv_done(struct ib_cq *cq, struct ib_wc *wc)
1396 {
1397 	struct isert_conn *isert_conn = wc->qp->qp_context;
1398 	struct ib_device *ib_dev = isert_conn->device->ib_device;
1399 
1400 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1401 		isert_print_wc(wc, "login recv");
1402 		return;
1403 	}
1404 
1405 	ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_desc->dma_addr,
1406 			ISER_RX_SIZE, DMA_FROM_DEVICE);
1407 
1408 	if (unlikely(wc->byte_len < ISER_HEADERS_LEN)) {
1409 		isert_dbg("login request length %u is too short\n",
1410 			  wc->byte_len);
1411 		return;
1412 	}
1413 
1414 	isert_conn->login_req_len = wc->byte_len - ISER_HEADERS_LEN;
1415 
1416 	if (isert_conn->conn) {
1417 		struct iscsi_login *login = isert_conn->conn->conn_login;
1418 
1419 		if (login && !login->first_request) {
1420 			if (isert_check_login_req(isert_conn))
1421 				return;
1422 
1423 			isert_rx_login_req(isert_conn);
1424 		}
1425 	}
1426 
1427 	mutex_lock(&isert_conn->mutex);
1428 	complete(&isert_conn->login_req_comp);
1429 	mutex_unlock(&isert_conn->mutex);
1430 
1431 	ib_dma_sync_single_for_device(ib_dev, isert_conn->login_desc->dma_addr,
1432 				ISER_RX_SIZE, DMA_FROM_DEVICE);
1433 }
1434 
1435 static void
1436 isert_rdma_rw_ctx_destroy(struct isert_cmd *cmd, struct isert_conn *conn)
1437 {
1438 	struct se_cmd *se_cmd = &cmd->iscsit_cmd->se_cmd;
1439 	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
1440 
1441 	if (!cmd->rw.nr_ops)
1442 		return;
1443 
1444 	if (isert_prot_cmd(conn, se_cmd)) {
1445 		rdma_rw_ctx_destroy_signature(&cmd->rw, conn->qp,
1446 				conn->cm_id->port_num, se_cmd->t_data_sg,
1447 				se_cmd->t_data_nents, se_cmd->t_prot_sg,
1448 				se_cmd->t_prot_nents, dir);
1449 	} else {
1450 		rdma_rw_ctx_destroy(&cmd->rw, conn->qp, conn->cm_id->port_num,
1451 				se_cmd->t_data_sg, se_cmd->t_data_nents, dir);
1452 	}
1453 
1454 	cmd->rw.nr_ops = 0;
1455 }
1456 
1457 static void
1458 isert_put_cmd(struct isert_cmd *isert_cmd, bool comp_err)
1459 {
1460 	struct iscsit_cmd *cmd = isert_cmd->iscsit_cmd;
1461 	struct isert_conn *isert_conn = isert_cmd->conn;
1462 	struct iscsit_conn *conn = isert_conn->conn;
1463 	struct iscsi_text_rsp *hdr;
1464 
1465 	isert_dbg("Cmd %p\n", isert_cmd);
1466 
1467 	switch (cmd->iscsi_opcode) {
1468 	case ISCSI_OP_SCSI_CMD:
1469 		spin_lock_bh(&conn->cmd_lock);
1470 		if (!list_empty(&cmd->i_conn_node))
1471 			list_del_init(&cmd->i_conn_node);
1472 		spin_unlock_bh(&conn->cmd_lock);
1473 
1474 		if (cmd->data_direction == DMA_TO_DEVICE) {
1475 			iscsit_stop_dataout_timer(cmd);
1476 			/*
1477 			 * Check for special case during comp_err where
1478 			 * WRITE_PENDING has been handed off from core,
1479 			 * but requires an extra target_put_sess_cmd()
1480 			 * before transport_generic_free_cmd() below.
1481 			 */
1482 			if (comp_err &&
1483 			    cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
1484 				struct se_cmd *se_cmd = &cmd->se_cmd;
1485 
1486 				target_put_sess_cmd(se_cmd);
1487 			}
1488 		}
1489 
1490 		isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1491 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1492 		break;
1493 	case ISCSI_OP_SCSI_TMFUNC:
1494 		spin_lock_bh(&conn->cmd_lock);
1495 		if (!list_empty(&cmd->i_conn_node))
1496 			list_del_init(&cmd->i_conn_node);
1497 		spin_unlock_bh(&conn->cmd_lock);
1498 
1499 		transport_generic_free_cmd(&cmd->se_cmd, 0);
1500 		break;
1501 	case ISCSI_OP_REJECT:
1502 	case ISCSI_OP_NOOP_OUT:
1503 	case ISCSI_OP_TEXT:
1504 		hdr = (struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1505 		/* If the continue bit is on, keep the command alive */
1506 		if (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)
1507 			break;
1508 
1509 		spin_lock_bh(&conn->cmd_lock);
1510 		if (!list_empty(&cmd->i_conn_node))
1511 			list_del_init(&cmd->i_conn_node);
1512 		spin_unlock_bh(&conn->cmd_lock);
1513 
1514 		/*
1515 		 * Handle special case for REJECT when iscsi_add_reject*() has
1516 		 * overwritten the original iscsi_opcode assignment, and the
1517 		 * associated cmd->se_cmd needs to be released.
1518 		 */
1519 		if (cmd->se_cmd.se_tfo != NULL) {
1520 			isert_dbg("Calling transport_generic_free_cmd for 0x%02x\n",
1521 				 cmd->iscsi_opcode);
1522 			transport_generic_free_cmd(&cmd->se_cmd, 0);
1523 			break;
1524 		}
1525 		fallthrough;
1526 	default:
1527 		iscsit_release_cmd(cmd);
1528 		break;
1529 	}
1530 }
1531 
1532 static void
1533 isert_unmap_tx_desc(struct iser_tx_desc *tx_desc, struct ib_device *ib_dev)
1534 {
1535 	if (tx_desc->dma_addr != 0) {
1536 		isert_dbg("unmap single for tx_desc->dma_addr\n");
1537 		ib_dma_unmap_single(ib_dev, tx_desc->dma_addr,
1538 				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
1539 		tx_desc->dma_addr = 0;
1540 	}
1541 }
1542 
1543 static void
1544 isert_completion_put(struct iser_tx_desc *tx_desc, struct isert_cmd *isert_cmd,
1545 		     struct ib_device *ib_dev, bool comp_err)
1546 {
1547 	if (isert_cmd->pdu_buf_dma != 0) {
1548 		isert_dbg("unmap single for isert_cmd->pdu_buf_dma\n");
1549 		ib_dma_unmap_single(ib_dev, isert_cmd->pdu_buf_dma,
1550 				    isert_cmd->pdu_buf_len, DMA_TO_DEVICE);
1551 		isert_cmd->pdu_buf_dma = 0;
1552 	}
1553 
1554 	isert_unmap_tx_desc(tx_desc, ib_dev);
1555 	isert_put_cmd(isert_cmd, comp_err);
1556 }
1557 
1558 static int
1559 isert_check_pi_status(struct se_cmd *se_cmd, struct ib_mr *sig_mr)
1560 {
1561 	struct ib_mr_status mr_status;
1562 	int ret;
1563 
1564 	ret = ib_check_mr_status(sig_mr, IB_MR_CHECK_SIG_STATUS, &mr_status);
1565 	if (ret) {
1566 		isert_err("ib_check_mr_status failed, ret %d\n", ret);
1567 		goto fail_mr_status;
1568 	}
1569 
1570 	if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
1571 		u64 sec_offset_err;
1572 		u32 block_size = se_cmd->se_dev->dev_attrib.block_size + 8;
1573 
1574 		switch (mr_status.sig_err.err_type) {
1575 		case IB_SIG_BAD_GUARD:
1576 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1577 			break;
1578 		case IB_SIG_BAD_REFTAG:
1579 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1580 			break;
1581 		case IB_SIG_BAD_APPTAG:
1582 			se_cmd->pi_err = TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED;
1583 			break;
1584 		}
1585 		sec_offset_err = mr_status.sig_err.sig_err_offset;
1586 		do_div(sec_offset_err, block_size);
1587 		se_cmd->sense_info = sec_offset_err + se_cmd->t_task_lba;
1588 
1589 		isert_err("PI error found type %d at sector 0x%llx "
1590 			  "expected 0x%x vs actual 0x%x\n",
1591 			  mr_status.sig_err.err_type,
1592 			  (unsigned long long)se_cmd->sense_info,
1593 			  mr_status.sig_err.expected,
1594 			  mr_status.sig_err.actual);
1595 		ret = 1;
1596 	}
1597 
1598 fail_mr_status:
1599 	return ret;
1600 }
1601 
1602 static void
1603 isert_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
1604 {
1605 	struct isert_conn *isert_conn = wc->qp->qp_context;
1606 	struct isert_device *device = isert_conn->device;
1607 	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
1608 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
1609 	struct se_cmd *cmd = &isert_cmd->iscsit_cmd->se_cmd;
1610 	int ret = 0;
1611 
1612 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1613 		isert_print_wc(wc, "rdma write");
1614 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1615 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1616 		isert_completion_put(desc, isert_cmd, device->ib_device, true);
1617 		return;
1618 	}
1619 
1620 	isert_dbg("Cmd %p\n", isert_cmd);
1621 
1622 	ret = isert_check_pi_status(cmd, isert_cmd->rw.reg->mr);
1623 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1624 
1625 	if (ret) {
1626 		/*
1627 		 * transport_generic_request_failure() expects to have
1628 		 * plus two references to handle queue-full, so re-add
1629 		 * one here as target-core will have already dropped
1630 		 * it after the first isert_put_datain() callback.
1631 		 */
1632 		kref_get(&cmd->cmd_kref);
1633 		transport_generic_request_failure(cmd, cmd->pi_err);
1634 	} else {
1635 		/*
1636 		 * XXX: isert_put_response() failure is not retried.
1637 		 */
1638 		ret = isert_put_response(isert_conn->conn, isert_cmd->iscsit_cmd);
1639 		if (ret)
1640 			pr_warn_ratelimited("isert_put_response() ret: %d\n", ret);
1641 	}
1642 }
1643 
1644 static void
1645 isert_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc)
1646 {
1647 	struct isert_conn *isert_conn = wc->qp->qp_context;
1648 	struct isert_device *device = isert_conn->device;
1649 	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
1650 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
1651 	struct iscsit_cmd *cmd = isert_cmd->iscsit_cmd;
1652 	struct se_cmd *se_cmd = &cmd->se_cmd;
1653 	int ret = 0;
1654 
1655 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1656 		isert_print_wc(wc, "rdma read");
1657 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1658 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1659 		isert_completion_put(desc, isert_cmd, device->ib_device, true);
1660 		return;
1661 	}
1662 
1663 	isert_dbg("Cmd %p\n", isert_cmd);
1664 
1665 	iscsit_stop_dataout_timer(cmd);
1666 
1667 	if (isert_prot_cmd(isert_conn, se_cmd))
1668 		ret = isert_check_pi_status(se_cmd, isert_cmd->rw.reg->mr);
1669 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1670 	cmd->write_data_done = 0;
1671 
1672 	isert_dbg("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
1673 	spin_lock_bh(&cmd->istate_lock);
1674 	cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1675 	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1676 	spin_unlock_bh(&cmd->istate_lock);
1677 
1678 	/*
1679 	 * transport_generic_request_failure() will drop the extra
1680 	 * se_cmd->cmd_kref reference after T10-PI error, and handle
1681 	 * any non-zero ->queue_status() callback error retries.
1682 	 */
1683 	if (ret)
1684 		transport_generic_request_failure(se_cmd, se_cmd->pi_err);
1685 	else
1686 		target_execute_cmd(se_cmd);
1687 }
1688 
1689 static void
1690 isert_do_control_comp(struct work_struct *work)
1691 {
1692 	struct isert_cmd *isert_cmd = container_of(work,
1693 			struct isert_cmd, comp_work);
1694 	struct isert_conn *isert_conn = isert_cmd->conn;
1695 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1696 	struct iscsit_cmd *cmd = isert_cmd->iscsit_cmd;
1697 
1698 	isert_dbg("Cmd %p i_state %d\n", isert_cmd, cmd->i_state);
1699 
1700 	switch (cmd->i_state) {
1701 	case ISTATE_SEND_TASKMGTRSP:
1702 		iscsit_tmr_post_handler(cmd, cmd->conn);
1703 		fallthrough;
1704 	case ISTATE_SEND_REJECT:
1705 	case ISTATE_SEND_TEXTRSP:
1706 		cmd->i_state = ISTATE_SENT_STATUS;
1707 		isert_completion_put(&isert_cmd->tx_desc, isert_cmd,
1708 				     ib_dev, false);
1709 		break;
1710 	case ISTATE_SEND_LOGOUTRSP:
1711 		iscsit_logout_post_handler(cmd, cmd->conn);
1712 		break;
1713 	default:
1714 		isert_err("Unknown i_state %d\n", cmd->i_state);
1715 		dump_stack();
1716 		break;
1717 	}
1718 }
1719 
1720 static void
1721 isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc)
1722 {
1723 	struct isert_conn *isert_conn = wc->qp->qp_context;
1724 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1725 	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
1726 
1727 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1728 		isert_print_wc(wc, "login send");
1729 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1730 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1731 	}
1732 
1733 	isert_unmap_tx_desc(tx_desc, ib_dev);
1734 }
1735 
1736 static void
1737 isert_send_done(struct ib_cq *cq, struct ib_wc *wc)
1738 {
1739 	struct isert_conn *isert_conn = wc->qp->qp_context;
1740 	struct ib_device *ib_dev = isert_conn->cm_id->device;
1741 	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
1742 	struct isert_cmd *isert_cmd = tx_desc_to_cmd(tx_desc);
1743 
1744 	if (unlikely(wc->status != IB_WC_SUCCESS)) {
1745 		isert_print_wc(wc, "send");
1746 		if (wc->status != IB_WC_WR_FLUSH_ERR)
1747 			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
1748 		isert_completion_put(tx_desc, isert_cmd, ib_dev, true);
1749 		return;
1750 	}
1751 
1752 	isert_dbg("Cmd %p\n", isert_cmd);
1753 
1754 	switch (isert_cmd->iscsit_cmd->i_state) {
1755 	case ISTATE_SEND_TASKMGTRSP:
1756 	case ISTATE_SEND_LOGOUTRSP:
1757 	case ISTATE_SEND_REJECT:
1758 	case ISTATE_SEND_TEXTRSP:
1759 		isert_unmap_tx_desc(tx_desc, ib_dev);
1760 
1761 		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
1762 		queue_work(isert_comp_wq, &isert_cmd->comp_work);
1763 		return;
1764 	default:
1765 		isert_cmd->iscsit_cmd->i_state = ISTATE_SENT_STATUS;
1766 		isert_completion_put(tx_desc, isert_cmd, ib_dev, false);
1767 		break;
1768 	}
1769 }
1770 
1771 static int
1772 isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
1773 {
1774 	int ret;
1775 
1776 	ret = isert_post_recv(isert_conn, isert_cmd->rx_desc);
1777 	if (ret)
1778 		return ret;
1779 
1780 	ret = ib_post_send(isert_conn->qp, &isert_cmd->tx_desc.send_wr, NULL);
1781 	if (ret) {
1782 		isert_err("ib_post_send failed with %d\n", ret);
1783 		return ret;
1784 	}
1785 	return ret;
1786 }
1787 
1788 static int
1789 isert_put_response(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
1790 {
1791 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1792 	struct isert_conn *isert_conn = conn->context;
1793 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1794 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
1795 				&isert_cmd->tx_desc.iscsi_header;
1796 
1797 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1798 	iscsit_build_rsp_pdu(cmd, conn, true, hdr);
1799 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1800 	/*
1801 	 * Attach SENSE DATA payload to iSCSI Response PDU
1802 	 */
1803 	if (cmd->se_cmd.sense_buffer &&
1804 	    ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
1805 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
1806 		struct isert_device *device = isert_conn->device;
1807 		struct ib_device *ib_dev = device->ib_device;
1808 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1809 		u32 padding, pdu_len;
1810 
1811 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length,
1812 				   cmd->sense_buffer);
1813 		cmd->se_cmd.scsi_sense_length += sizeof(__be16);
1814 
1815 		padding = -(cmd->se_cmd.scsi_sense_length) & 3;
1816 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
1817 		pdu_len = cmd->se_cmd.scsi_sense_length + padding;
1818 
1819 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1820 				(void *)cmd->sense_buffer, pdu_len,
1821 				DMA_TO_DEVICE);
1822 		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1823 			return -ENOMEM;
1824 
1825 		isert_cmd->pdu_buf_len = pdu_len;
1826 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1827 		tx_dsg->length	= pdu_len;
1828 		tx_dsg->lkey	= device->pd->local_dma_lkey;
1829 		isert_cmd->tx_desc.num_sge = 2;
1830 	}
1831 
1832 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1833 
1834 	isert_dbg("Posting SCSI Response\n");
1835 
1836 	return isert_post_response(isert_conn, isert_cmd);
1837 }
1838 
1839 static void
1840 isert_aborted_task(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
1841 {
1842 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1843 	struct isert_conn *isert_conn = conn->context;
1844 
1845 	spin_lock_bh(&conn->cmd_lock);
1846 	if (!list_empty(&cmd->i_conn_node))
1847 		list_del_init(&cmd->i_conn_node);
1848 	spin_unlock_bh(&conn->cmd_lock);
1849 
1850 	if (cmd->data_direction == DMA_TO_DEVICE)
1851 		iscsit_stop_dataout_timer(cmd);
1852 	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
1853 }
1854 
1855 static enum target_prot_op
1856 isert_get_sup_prot_ops(struct iscsit_conn *conn)
1857 {
1858 	struct isert_conn *isert_conn = conn->context;
1859 	struct isert_device *device = isert_conn->device;
1860 
1861 	if (conn->tpg->tpg_attrib.t10_pi) {
1862 		if (device->pi_capable) {
1863 			isert_info("conn %p PI offload enabled\n", isert_conn);
1864 			isert_conn->pi_support = true;
1865 			return TARGET_PROT_ALL;
1866 		}
1867 	}
1868 
1869 	isert_info("conn %p PI offload disabled\n", isert_conn);
1870 	isert_conn->pi_support = false;
1871 
1872 	return TARGET_PROT_NORMAL;
1873 }
1874 
1875 static int
1876 isert_put_nopin(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
1877 		bool nopout_response)
1878 {
1879 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1880 	struct isert_conn *isert_conn = conn->context;
1881 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1882 
1883 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1884 	iscsit_build_nopin_rsp(cmd, conn, (struct iscsi_nopin *)
1885 			       &isert_cmd->tx_desc.iscsi_header,
1886 			       nopout_response);
1887 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1888 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1889 
1890 	isert_dbg("conn %p Posting NOPIN Response\n", isert_conn);
1891 
1892 	return isert_post_response(isert_conn, isert_cmd);
1893 }
1894 
1895 static int
1896 isert_put_logout_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
1897 {
1898 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1899 	struct isert_conn *isert_conn = conn->context;
1900 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1901 
1902 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1903 	iscsit_build_logout_rsp(cmd, conn, (struct iscsi_logout_rsp *)
1904 				&isert_cmd->tx_desc.iscsi_header);
1905 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1906 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1907 
1908 	isert_dbg("conn %p Posting Logout Response\n", isert_conn);
1909 
1910 	return isert_post_response(isert_conn, isert_cmd);
1911 }
1912 
1913 static int
1914 isert_put_tm_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
1915 {
1916 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1917 	struct isert_conn *isert_conn = conn->context;
1918 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1919 
1920 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1921 	iscsit_build_task_mgt_rsp(cmd, conn, (struct iscsi_tm_rsp *)
1922 				  &isert_cmd->tx_desc.iscsi_header);
1923 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1924 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1925 
1926 	isert_dbg("conn %p Posting Task Management Response\n", isert_conn);
1927 
1928 	return isert_post_response(isert_conn, isert_cmd);
1929 }
1930 
1931 static int
1932 isert_put_reject(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
1933 {
1934 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1935 	struct isert_conn *isert_conn = conn->context;
1936 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1937 	struct isert_device *device = isert_conn->device;
1938 	struct ib_device *ib_dev = device->ib_device;
1939 	struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1940 	struct iscsi_reject *hdr =
1941 		(struct iscsi_reject *)&isert_cmd->tx_desc.iscsi_header;
1942 
1943 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1944 	iscsit_build_reject(cmd, conn, hdr);
1945 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1946 
1947 	hton24(hdr->dlength, ISCSI_HDR_LEN);
1948 	isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1949 			(void *)cmd->buf_ptr, ISCSI_HDR_LEN,
1950 			DMA_TO_DEVICE);
1951 	if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1952 		return -ENOMEM;
1953 	isert_cmd->pdu_buf_len = ISCSI_HDR_LEN;
1954 	tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1955 	tx_dsg->length	= ISCSI_HDR_LEN;
1956 	tx_dsg->lkey	= device->pd->local_dma_lkey;
1957 	isert_cmd->tx_desc.num_sge = 2;
1958 
1959 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
1960 
1961 	isert_dbg("conn %p Posting Reject\n", isert_conn);
1962 
1963 	return isert_post_response(isert_conn, isert_cmd);
1964 }
1965 
1966 static int
1967 isert_put_text_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
1968 {
1969 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
1970 	struct isert_conn *isert_conn = conn->context;
1971 	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
1972 	struct iscsi_text_rsp *hdr =
1973 		(struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
1974 	u32 txt_rsp_len;
1975 	int rc;
1976 
1977 	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
1978 	rc = iscsit_build_text_rsp(cmd, conn, hdr, ISCSI_INFINIBAND);
1979 	if (rc < 0)
1980 		return rc;
1981 
1982 	txt_rsp_len = rc;
1983 	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
1984 
1985 	if (txt_rsp_len) {
1986 		struct isert_device *device = isert_conn->device;
1987 		struct ib_device *ib_dev = device->ib_device;
1988 		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
1989 		void *txt_rsp_buf = cmd->buf_ptr;
1990 
1991 		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
1992 				txt_rsp_buf, txt_rsp_len, DMA_TO_DEVICE);
1993 		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
1994 			return -ENOMEM;
1995 
1996 		isert_cmd->pdu_buf_len = txt_rsp_len;
1997 		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
1998 		tx_dsg->length	= txt_rsp_len;
1999 		tx_dsg->lkey	= device->pd->local_dma_lkey;
2000 		isert_cmd->tx_desc.num_sge = 2;
2001 	}
2002 	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
2003 
2004 	isert_dbg("conn %p Text Response\n", isert_conn);
2005 
2006 	return isert_post_response(isert_conn, isert_cmd);
2007 }
2008 
2009 static inline void
2010 isert_set_dif_domain(struct se_cmd *se_cmd, struct ib_sig_domain *domain)
2011 {
2012 	domain->sig_type = IB_SIG_TYPE_T10_DIF;
2013 	domain->sig.dif.bg_type = IB_T10DIF_CRC;
2014 	domain->sig.dif.pi_interval = se_cmd->se_dev->dev_attrib.block_size;
2015 	domain->sig.dif.ref_tag = se_cmd->reftag_seed;
2016 	/*
2017 	 * At the moment we hard code those, but if in the future
2018 	 * the target core would like to use it, we will take it
2019 	 * from se_cmd.
2020 	 */
2021 	domain->sig.dif.apptag_check_mask = 0xffff;
2022 	domain->sig.dif.app_escape = true;
2023 	domain->sig.dif.ref_escape = true;
2024 	if (se_cmd->prot_type == TARGET_DIF_TYPE1_PROT ||
2025 	    se_cmd->prot_type == TARGET_DIF_TYPE2_PROT)
2026 		domain->sig.dif.ref_remap = true;
2027 }
2028 
2029 static int
2030 isert_set_sig_attrs(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs)
2031 {
2032 	memset(sig_attrs, 0, sizeof(*sig_attrs));
2033 
2034 	switch (se_cmd->prot_op) {
2035 	case TARGET_PROT_DIN_INSERT:
2036 	case TARGET_PROT_DOUT_STRIP:
2037 		sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
2038 		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
2039 		break;
2040 	case TARGET_PROT_DOUT_INSERT:
2041 	case TARGET_PROT_DIN_STRIP:
2042 		sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
2043 		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
2044 		break;
2045 	case TARGET_PROT_DIN_PASS:
2046 	case TARGET_PROT_DOUT_PASS:
2047 		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
2048 		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
2049 		break;
2050 	default:
2051 		isert_err("Unsupported PI operation %d\n", se_cmd->prot_op);
2052 		return -EINVAL;
2053 	}
2054 
2055 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_GUARD)
2056 		sig_attrs->check_mask |= IB_SIG_CHECK_GUARD;
2057 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_APPTAG)
2058 		sig_attrs->check_mask |= IB_SIG_CHECK_APPTAG;
2059 	if (se_cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)
2060 		sig_attrs->check_mask |= IB_SIG_CHECK_REFTAG;
2061 
2062 	return 0;
2063 }
2064 
2065 static int
2066 isert_rdma_rw_ctx_post(struct isert_cmd *cmd, struct isert_conn *conn,
2067 		struct ib_cqe *cqe, struct ib_send_wr *chain_wr)
2068 {
2069 	struct se_cmd *se_cmd = &cmd->iscsit_cmd->se_cmd;
2070 	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
2071 	u8 port_num = conn->cm_id->port_num;
2072 	u64 addr;
2073 	u32 rkey, offset;
2074 	int ret;
2075 
2076 	if (cmd->ctx_init_done)
2077 		goto rdma_ctx_post;
2078 
2079 	if (dir == DMA_FROM_DEVICE) {
2080 		addr = cmd->write_va;
2081 		rkey = cmd->write_stag;
2082 		offset = cmd->iscsit_cmd->write_data_done;
2083 	} else {
2084 		addr = cmd->read_va;
2085 		rkey = cmd->read_stag;
2086 		offset = 0;
2087 	}
2088 
2089 	if (isert_prot_cmd(conn, se_cmd)) {
2090 		struct ib_sig_attrs sig_attrs;
2091 
2092 		ret = isert_set_sig_attrs(se_cmd, &sig_attrs);
2093 		if (ret)
2094 			return ret;
2095 
2096 		WARN_ON_ONCE(offset);
2097 		ret = rdma_rw_ctx_signature_init(&cmd->rw, conn->qp, port_num,
2098 				se_cmd->t_data_sg, se_cmd->t_data_nents,
2099 				se_cmd->t_prot_sg, se_cmd->t_prot_nents,
2100 				&sig_attrs, addr, rkey, dir);
2101 	} else {
2102 		ret = rdma_rw_ctx_init(&cmd->rw, conn->qp, port_num,
2103 				se_cmd->t_data_sg, se_cmd->t_data_nents,
2104 				offset, addr, rkey, dir);
2105 	}
2106 
2107 	if (ret < 0) {
2108 		isert_err("Cmd: %p failed to prepare RDMA res\n", cmd);
2109 		return ret;
2110 	}
2111 
2112 	cmd->ctx_init_done = true;
2113 
2114 rdma_ctx_post:
2115 	ret = rdma_rw_ctx_post(&cmd->rw, conn->qp, port_num, cqe, chain_wr);
2116 	if (ret < 0)
2117 		isert_err("Cmd: %p failed to post RDMA res\n", cmd);
2118 	return ret;
2119 }
2120 
2121 static int
2122 isert_put_datain(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
2123 {
2124 	struct se_cmd *se_cmd = &cmd->se_cmd;
2125 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2126 	struct isert_conn *isert_conn = conn->context;
2127 	struct ib_cqe *cqe = NULL;
2128 	struct ib_send_wr *chain_wr = NULL;
2129 	int rc;
2130 
2131 	isert_dbg("Cmd: %p RDMA_WRITE data_length: %u\n",
2132 		 isert_cmd, se_cmd->data_length);
2133 
2134 	if (isert_prot_cmd(isert_conn, se_cmd)) {
2135 		isert_cmd->tx_desc.tx_cqe.done = isert_rdma_write_done;
2136 		cqe = &isert_cmd->tx_desc.tx_cqe;
2137 	} else {
2138 		/*
2139 		 * Build isert_conn->tx_desc for iSCSI response PDU and attach
2140 		 */
2141 		isert_create_send_desc(isert_conn, isert_cmd,
2142 				       &isert_cmd->tx_desc);
2143 		iscsit_build_rsp_pdu(cmd, conn, true, (struct iscsi_scsi_rsp *)
2144 				     &isert_cmd->tx_desc.iscsi_header);
2145 		isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
2146 		isert_init_send_wr(isert_conn, isert_cmd,
2147 				   &isert_cmd->tx_desc.send_wr);
2148 
2149 		rc = isert_post_recv(isert_conn, isert_cmd->rx_desc);
2150 		if (rc)
2151 			return rc;
2152 
2153 		chain_wr = &isert_cmd->tx_desc.send_wr;
2154 	}
2155 
2156 	rc = isert_rdma_rw_ctx_post(isert_cmd, isert_conn, cqe, chain_wr);
2157 	isert_dbg("Cmd: %p posted RDMA_WRITE for iSER Data READ rc: %d\n",
2158 		  isert_cmd, rc);
2159 	return rc;
2160 }
2161 
2162 static int
2163 isert_get_dataout(struct iscsit_conn *conn, struct iscsit_cmd *cmd, bool recovery)
2164 {
2165 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2166 	int ret;
2167 
2168 	isert_dbg("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
2169 		 isert_cmd, cmd->se_cmd.data_length, cmd->write_data_done);
2170 
2171 	isert_cmd->tx_desc.tx_cqe.done = isert_rdma_read_done;
2172 	ret = isert_rdma_rw_ctx_post(isert_cmd, conn->context,
2173 				     &isert_cmd->tx_desc.tx_cqe, NULL);
2174 
2175 	isert_dbg("Cmd: %p posted RDMA_READ memory for ISER Data WRITE rc: %d\n",
2176 		 isert_cmd, ret);
2177 	return ret;
2178 }
2179 
2180 static int
2181 isert_immediate_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
2182 {
2183 	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2184 	int ret = 0;
2185 
2186 	switch (state) {
2187 	case ISTATE_REMOVE:
2188 		spin_lock_bh(&conn->cmd_lock);
2189 		list_del_init(&cmd->i_conn_node);
2190 		spin_unlock_bh(&conn->cmd_lock);
2191 		isert_put_cmd(isert_cmd, true);
2192 		break;
2193 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
2194 		ret = isert_put_nopin(cmd, conn, false);
2195 		break;
2196 	default:
2197 		isert_err("Unknown immediate state: 0x%02x\n", state);
2198 		ret = -EINVAL;
2199 		break;
2200 	}
2201 
2202 	return ret;
2203 }
2204 
2205 static int
2206 isert_response_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
2207 {
2208 	struct isert_conn *isert_conn = conn->context;
2209 	int ret;
2210 
2211 	switch (state) {
2212 	case ISTATE_SEND_LOGOUTRSP:
2213 		ret = isert_put_logout_rsp(cmd, conn);
2214 		if (!ret)
2215 			isert_conn->logout_posted = true;
2216 		break;
2217 	case ISTATE_SEND_NOPIN:
2218 		ret = isert_put_nopin(cmd, conn, true);
2219 		break;
2220 	case ISTATE_SEND_TASKMGTRSP:
2221 		ret = isert_put_tm_rsp(cmd, conn);
2222 		break;
2223 	case ISTATE_SEND_REJECT:
2224 		ret = isert_put_reject(cmd, conn);
2225 		break;
2226 	case ISTATE_SEND_TEXTRSP:
2227 		ret = isert_put_text_rsp(cmd, conn);
2228 		break;
2229 	case ISTATE_SEND_STATUS:
2230 		/*
2231 		 * Special case for sending non GOOD SCSI status from TX thread
2232 		 * context during pre se_cmd excecution failure.
2233 		 */
2234 		ret = isert_put_response(conn, cmd);
2235 		break;
2236 	default:
2237 		isert_err("Unknown response state: 0x%02x\n", state);
2238 		ret = -EINVAL;
2239 		break;
2240 	}
2241 
2242 	return ret;
2243 }
2244 
2245 struct rdma_cm_id *
2246 isert_setup_id(struct isert_np *isert_np)
2247 {
2248 	struct iscsi_np *np = isert_np->np;
2249 	struct rdma_cm_id *id;
2250 	struct sockaddr *sa;
2251 	int ret;
2252 
2253 	sa = (struct sockaddr *)&np->np_sockaddr;
2254 	isert_dbg("ksockaddr: %p, sa: %p\n", &np->np_sockaddr, sa);
2255 
2256 	id = rdma_create_id(&init_net, isert_cma_handler, isert_np,
2257 			    RDMA_PS_TCP, IB_QPT_RC);
2258 	if (IS_ERR(id)) {
2259 		isert_err("rdma_create_id() failed: %ld\n", PTR_ERR(id));
2260 		ret = PTR_ERR(id);
2261 		goto out;
2262 	}
2263 	isert_dbg("id %p context %p\n", id, id->context);
2264 
2265 	/*
2266 	 * Allow both IPv4 and IPv6 sockets to bind a single port
2267 	 * at the same time.
2268 	 */
2269 	ret = rdma_set_afonly(id, 1);
2270 	if (ret) {
2271 		isert_err("rdma_set_afonly() failed: %d\n", ret);
2272 		goto out_id;
2273 	}
2274 
2275 	ret = rdma_bind_addr(id, sa);
2276 	if (ret) {
2277 		isert_err("rdma_bind_addr() failed: %d\n", ret);
2278 		goto out_id;
2279 	}
2280 
2281 	ret = rdma_listen(id, 0);
2282 	if (ret) {
2283 		isert_err("rdma_listen() failed: %d\n", ret);
2284 		goto out_id;
2285 	}
2286 
2287 	return id;
2288 out_id:
2289 	rdma_destroy_id(id);
2290 out:
2291 	return ERR_PTR(ret);
2292 }
2293 
2294 static int
2295 isert_setup_np(struct iscsi_np *np,
2296 	       struct sockaddr_storage *ksockaddr)
2297 {
2298 	struct isert_np *isert_np;
2299 	struct rdma_cm_id *isert_lid;
2300 	int ret;
2301 
2302 	isert_np = kzalloc_obj(struct isert_np);
2303 	if (!isert_np)
2304 		return -ENOMEM;
2305 
2306 	sema_init(&isert_np->sem, 0);
2307 	mutex_init(&isert_np->mutex);
2308 	INIT_LIST_HEAD(&isert_np->accepted);
2309 	INIT_LIST_HEAD(&isert_np->pending);
2310 	isert_np->np = np;
2311 
2312 	/*
2313 	 * Setup the np->np_sockaddr from the passed sockaddr setup
2314 	 * in iscsi_target_configfs.c code..
2315 	 */
2316 	memcpy(&np->np_sockaddr, ksockaddr,
2317 	       sizeof(struct sockaddr_storage));
2318 
2319 	isert_lid = isert_setup_id(isert_np);
2320 	if (IS_ERR(isert_lid)) {
2321 		ret = PTR_ERR(isert_lid);
2322 		goto out;
2323 	}
2324 
2325 	isert_np->cm_id = isert_lid;
2326 	np->np_context = isert_np;
2327 
2328 	return 0;
2329 
2330 out:
2331 	kfree(isert_np);
2332 
2333 	return ret;
2334 }
2335 
2336 static int
2337 isert_rdma_accept(struct isert_conn *isert_conn)
2338 {
2339 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
2340 	struct rdma_conn_param cp;
2341 	int ret;
2342 	struct iser_cm_hdr rsp_hdr;
2343 
2344 	memset(&cp, 0, sizeof(struct rdma_conn_param));
2345 	cp.initiator_depth = isert_conn->initiator_depth;
2346 	cp.retry_count = 7;
2347 	cp.rnr_retry_count = 7;
2348 
2349 	memset(&rsp_hdr, 0, sizeof(rsp_hdr));
2350 	rsp_hdr.flags = ISERT_ZBVA_NOT_USED;
2351 	if (!isert_conn->snd_w_inv)
2352 		rsp_hdr.flags = rsp_hdr.flags | ISERT_SEND_W_INV_NOT_USED;
2353 	cp.private_data = (void *)&rsp_hdr;
2354 	cp.private_data_len = sizeof(rsp_hdr);
2355 
2356 	ret = rdma_accept(cm_id, &cp);
2357 	if (ret) {
2358 		isert_err("rdma_accept() failed with: %d\n", ret);
2359 		return ret;
2360 	}
2361 
2362 	return 0;
2363 }
2364 
2365 static int
2366 isert_get_login_rx(struct iscsit_conn *conn, struct iscsi_login *login)
2367 {
2368 	struct isert_conn *isert_conn = conn->context;
2369 	int ret;
2370 
2371 	isert_info("before login_req comp conn: %p\n", isert_conn);
2372 	ret = wait_for_completion_interruptible(&isert_conn->login_req_comp);
2373 	if (ret) {
2374 		isert_err("isert_conn %p interrupted before got login req\n",
2375 			  isert_conn);
2376 		return ret;
2377 	}
2378 	reinit_completion(&isert_conn->login_req_comp);
2379 
2380 	/*
2381 	 * For login requests after the first PDU, isert_rx_login_req() will
2382 	 * kick queue_delayed_work(isert_login_wq, &conn->login_work) as
2383 	 * the packet is received, which turns this callback from
2384 	 * iscsi_target_do_login_rx() into a NOP.
2385 	 */
2386 	if (!login->first_request)
2387 		return 0;
2388 
2389 	ret = isert_check_login_req(isert_conn);
2390 	if (ret)
2391 		return ret;
2392 
2393 	isert_rx_login_req(isert_conn);
2394 
2395 	isert_info("before login_comp conn: %p\n", conn);
2396 	ret = wait_for_completion_interruptible(&isert_conn->login_comp);
2397 	if (ret)
2398 		return ret;
2399 
2400 	isert_info("processing login->req: %p\n", login->req);
2401 
2402 	return 0;
2403 }
2404 
2405 static void
2406 isert_set_conn_info(struct iscsi_np *np, struct iscsit_conn *conn,
2407 		    struct isert_conn *isert_conn)
2408 {
2409 	struct rdma_cm_id *cm_id = isert_conn->cm_id;
2410 	struct rdma_route *cm_route = &cm_id->route;
2411 
2412 	conn->login_family = np->np_sockaddr.ss_family;
2413 
2414 	conn->login_sockaddr = cm_route->addr.dst_addr;
2415 	conn->local_sockaddr = cm_route->addr.src_addr;
2416 }
2417 
2418 static int
2419 isert_accept_np(struct iscsi_np *np, struct iscsit_conn *conn)
2420 {
2421 	struct isert_np *isert_np = np->np_context;
2422 	struct isert_conn *isert_conn;
2423 	int ret;
2424 
2425 accept_wait:
2426 	ret = down_interruptible(&isert_np->sem);
2427 	if (ret)
2428 		return -ENODEV;
2429 
2430 	spin_lock_bh(&np->np_thread_lock);
2431 	if (np->np_thread_state >= ISCSI_NP_THREAD_RESET) {
2432 		spin_unlock_bh(&np->np_thread_lock);
2433 		isert_dbg("np_thread_state %d\n",
2434 			 np->np_thread_state);
2435 		/*
2436 		 * No point in stalling here when np_thread
2437 		 * is in state RESET/SHUTDOWN/EXIT - bail
2438 		 */
2439 		return -ENODEV;
2440 	}
2441 	spin_unlock_bh(&np->np_thread_lock);
2442 
2443 	mutex_lock(&isert_np->mutex);
2444 	if (list_empty(&isert_np->pending)) {
2445 		mutex_unlock(&isert_np->mutex);
2446 		goto accept_wait;
2447 	}
2448 	isert_conn = list_first_entry(&isert_np->pending,
2449 			struct isert_conn, node);
2450 	list_del_init(&isert_conn->node);
2451 	mutex_unlock(&isert_np->mutex);
2452 
2453 	conn->context = isert_conn;
2454 	isert_conn->conn = conn;
2455 	isert_conn->state = ISER_CONN_BOUND;
2456 
2457 	isert_set_conn_info(np, conn, isert_conn);
2458 
2459 	isert_dbg("Processing isert_conn: %p\n", isert_conn);
2460 
2461 	return 0;
2462 }
2463 
2464 static void
2465 isert_free_np(struct iscsi_np *np)
2466 {
2467 	struct isert_np *isert_np = np->np_context;
2468 	struct isert_conn *isert_conn, *n;
2469 	LIST_HEAD(drop_conn_list);
2470 
2471 	if (isert_np->cm_id)
2472 		rdma_destroy_id(isert_np->cm_id);
2473 
2474 	/*
2475 	 * FIXME: At this point we don't have a good way to insure
2476 	 * that at this point we don't have hanging connections that
2477 	 * completed RDMA establishment but didn't start iscsi login
2478 	 * process. So work-around this by cleaning up what ever piled
2479 	 * up in accepted and pending lists.
2480 	 */
2481 	mutex_lock(&isert_np->mutex);
2482 	if (!list_empty(&isert_np->pending)) {
2483 		isert_info("Still have isert pending connections\n");
2484 		list_for_each_entry_safe(isert_conn, n,
2485 					 &isert_np->pending,
2486 					 node) {
2487 			isert_info("cleaning isert_conn %p state (%d)\n",
2488 				   isert_conn, isert_conn->state);
2489 			list_move_tail(&isert_conn->node, &drop_conn_list);
2490 		}
2491 	}
2492 
2493 	if (!list_empty(&isert_np->accepted)) {
2494 		isert_info("Still have isert accepted connections\n");
2495 		list_for_each_entry_safe(isert_conn, n,
2496 					 &isert_np->accepted,
2497 					 node) {
2498 			isert_info("cleaning isert_conn %p state (%d)\n",
2499 				   isert_conn, isert_conn->state);
2500 			list_move_tail(&isert_conn->node, &drop_conn_list);
2501 		}
2502 	}
2503 	mutex_unlock(&isert_np->mutex);
2504 
2505 	list_for_each_entry_safe(isert_conn, n, &drop_conn_list, node) {
2506 		list_del_init(&isert_conn->node);
2507 		isert_connect_release(isert_conn);
2508 	}
2509 
2510 	np->np_context = NULL;
2511 	kfree(isert_np);
2512 }
2513 
2514 static void isert_release_work(struct work_struct *work)
2515 {
2516 	struct isert_conn *isert_conn = container_of(work,
2517 						     struct isert_conn,
2518 						     release_work);
2519 
2520 	isert_info("Starting release conn %p\n", isert_conn);
2521 
2522 	mutex_lock(&isert_conn->mutex);
2523 	isert_conn->state = ISER_CONN_DOWN;
2524 	mutex_unlock(&isert_conn->mutex);
2525 
2526 	isert_info("Destroying conn %p\n", isert_conn);
2527 	isert_put_conn(isert_conn);
2528 }
2529 
2530 static void
2531 isert_wait4logout(struct isert_conn *isert_conn)
2532 {
2533 	struct iscsit_conn *conn = isert_conn->conn;
2534 
2535 	isert_info("conn %p\n", isert_conn);
2536 
2537 	if (isert_conn->logout_posted) {
2538 		isert_info("conn %p wait for conn_logout_comp\n", isert_conn);
2539 		wait_for_completion_timeout(&conn->conn_logout_comp,
2540 					    SECONDS_FOR_LOGOUT_COMP * HZ);
2541 	}
2542 }
2543 
2544 static void
2545 isert_wait4cmds(struct iscsit_conn *conn)
2546 {
2547 	isert_info("iscsit_conn %p\n", conn);
2548 
2549 	if (conn->sess) {
2550 		target_stop_cmd_counter(conn->cmd_cnt);
2551 		target_wait_for_cmds(conn->cmd_cnt);
2552 	}
2553 }
2554 
2555 /**
2556  * isert_put_unsol_pending_cmds() - Drop commands waiting for
2557  *     unsolicitate dataout
2558  * @conn:    iscsi connection
2559  *
2560  * We might still have commands that are waiting for unsolicited
2561  * dataouts messages. We must put the extra reference on those
2562  * before blocking on the target_wait_for_session_cmds
2563  */
2564 static void
2565 isert_put_unsol_pending_cmds(struct iscsit_conn *conn)
2566 {
2567 	struct iscsit_cmd *cmd, *tmp;
2568 	static LIST_HEAD(drop_cmd_list);
2569 
2570 	spin_lock_bh(&conn->cmd_lock);
2571 	list_for_each_entry_safe(cmd, tmp, &conn->conn_cmd_list, i_conn_node) {
2572 		if ((cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA) &&
2573 		    (cmd->write_data_done < conn->sess->sess_ops->FirstBurstLength) &&
2574 		    (cmd->write_data_done < cmd->se_cmd.data_length))
2575 			list_move_tail(&cmd->i_conn_node, &drop_cmd_list);
2576 	}
2577 	spin_unlock_bh(&conn->cmd_lock);
2578 
2579 	list_for_each_entry_safe(cmd, tmp, &drop_cmd_list, i_conn_node) {
2580 		list_del_init(&cmd->i_conn_node);
2581 		if (cmd->i_state != ISTATE_REMOVE) {
2582 			struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
2583 
2584 			isert_info("conn %p dropping cmd %p\n", conn, cmd);
2585 			isert_put_cmd(isert_cmd, true);
2586 		}
2587 	}
2588 }
2589 
2590 static void isert_wait_conn(struct iscsit_conn *conn)
2591 {
2592 	struct isert_conn *isert_conn = conn->context;
2593 
2594 	isert_info("Starting conn %p\n", isert_conn);
2595 
2596 	mutex_lock(&isert_conn->mutex);
2597 	isert_conn_terminate(isert_conn);
2598 	mutex_unlock(&isert_conn->mutex);
2599 
2600 	ib_drain_qp(isert_conn->qp);
2601 	isert_put_unsol_pending_cmds(conn);
2602 	isert_wait4cmds(conn);
2603 	isert_wait4logout(isert_conn);
2604 
2605 	queue_work(isert_release_wq, &isert_conn->release_work);
2606 }
2607 
2608 static void isert_free_conn(struct iscsit_conn *conn)
2609 {
2610 	struct isert_conn *isert_conn = conn->context;
2611 
2612 	ib_drain_qp(isert_conn->qp);
2613 	isert_put_conn(isert_conn);
2614 }
2615 
2616 static void isert_get_rx_pdu(struct iscsit_conn *conn)
2617 {
2618 	struct isert_conn *isert_conn = conn->context;
2619 	struct completion comp;
2620 
2621 	/* The login timeout timer can fail the login after isert_put_login_tx(). */
2622 	if (!isert_conn->login_rsp_pending)
2623 		return;
2624 
2625 	isert_conn->login_rsp_pending = false;
2626 
2627 	/* The session is registered by now; see isert_put_login_tx(). */
2628 	if (isert_alloc_rx_descriptors(isert_conn))
2629 		return;
2630 
2631 	if (isert_post_recvm(isert_conn, ISERT_QP_MAX_RECV_DTOS))
2632 		return;
2633 
2634 	/* Now we are in FULL_FEATURE phase */
2635 	mutex_lock(&isert_conn->mutex);
2636 	isert_conn->state = ISER_CONN_FULL_FEATURE;
2637 	mutex_unlock(&isert_conn->mutex);
2638 
2639 	if (isert_login_post_send(isert_conn, &isert_conn->login_tx_desc))
2640 		return;
2641 
2642 	init_completion(&comp);
2643 
2644 	wait_for_completion_interruptible(&comp);
2645 }
2646 
2647 static struct iscsit_transport iser_target_transport = {
2648 	.name			= "IB/iSER",
2649 	.transport_type		= ISCSI_INFINIBAND,
2650 	.rdma_shutdown		= true,
2651 	.priv_size		= sizeof(struct isert_cmd),
2652 	.owner			= THIS_MODULE,
2653 	.iscsit_setup_np	= isert_setup_np,
2654 	.iscsit_accept_np	= isert_accept_np,
2655 	.iscsit_free_np		= isert_free_np,
2656 	.iscsit_wait_conn	= isert_wait_conn,
2657 	.iscsit_free_conn	= isert_free_conn,
2658 	.iscsit_get_login_rx	= isert_get_login_rx,
2659 	.iscsit_put_login_tx	= isert_put_login_tx,
2660 	.iscsit_immediate_queue	= isert_immediate_queue,
2661 	.iscsit_response_queue	= isert_response_queue,
2662 	.iscsit_get_dataout	= isert_get_dataout,
2663 	.iscsit_queue_data_in	= isert_put_datain,
2664 	.iscsit_queue_status	= isert_put_response,
2665 	.iscsit_aborted_task	= isert_aborted_task,
2666 	.iscsit_get_rx_pdu	= isert_get_rx_pdu,
2667 	.iscsit_get_sup_prot_ops = isert_get_sup_prot_ops,
2668 };
2669 
2670 static int __init isert_init(void)
2671 {
2672 	isert_login_wq = alloc_workqueue("isert_login_wq", WQ_PERCPU, 0);
2673 	if (!isert_login_wq) {
2674 		isert_err("Unable to allocate isert_login_wq\n");
2675 		return -ENOMEM;
2676 	}
2677 
2678 	isert_comp_wq = alloc_workqueue("isert_comp_wq",
2679 					WQ_UNBOUND | WQ_HIGHPRI, 0);
2680 	if (!isert_comp_wq) {
2681 		isert_err("Unable to allocate isert_comp_wq\n");
2682 		goto destroy_login_wq;
2683 	}
2684 
2685 	isert_release_wq = alloc_workqueue("isert_release_wq", WQ_UNBOUND,
2686 					WQ_UNBOUND_MAX_ACTIVE);
2687 	if (!isert_release_wq) {
2688 		isert_err("Unable to allocate isert_release_wq\n");
2689 		goto destroy_comp_wq;
2690 	}
2691 
2692 	iscsit_register_transport(&iser_target_transport);
2693 	isert_info("iSER_TARGET[0] - Loaded iser_target_transport\n");
2694 
2695 	return 0;
2696 
2697 destroy_comp_wq:
2698 	destroy_workqueue(isert_comp_wq);
2699 destroy_login_wq:
2700 	destroy_workqueue(isert_login_wq);
2701 
2702 	return -ENOMEM;
2703 }
2704 
2705 static void __exit isert_exit(void)
2706 {
2707 	flush_workqueue(isert_login_wq);
2708 	destroy_workqueue(isert_release_wq);
2709 	destroy_workqueue(isert_comp_wq);
2710 	iscsit_unregister_transport(&iser_target_transport);
2711 	isert_info("iSER_TARGET[0] - Released iser_target_transport\n");
2712 	destroy_workqueue(isert_login_wq);
2713 }
2714 
2715 MODULE_DESCRIPTION("iSER-Target for mainline target infrastructure");
2716 MODULE_AUTHOR("nab@Linux-iSCSI.org");
2717 MODULE_LICENSE("GPL");
2718 
2719 module_init(isert_init);
2720 module_exit(isert_exit);
2721