1 /*
2  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
3  * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *	- Redistributions of source code must retain the above
16  *	  copyright notice, this list of conditions and the following
17  *	  disclaimer.
18  *
19  *	- Redistributions in binary form must reproduce the above
20  *	  copyright notice, this list of conditions and the following
21  *	  disclaimer in the documentation and/or other materials
22  *	  provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 #include <linux/module.h>
34 #include <linux/kernel.h>
35 #include <linux/slab.h>
36 #include <linux/mm.h>
37 #include <linux/highmem.h>
38 #include <linux/scatterlist.h>
39 
40 #include "iscsi_iser.h"
41 static
42 int iser_fast_reg_fmr(struct iscsi_iser_task *iser_task,
43 		      struct iser_data_buf *mem,
44 		      struct iser_reg_resources *rsc,
45 		      struct iser_mem_reg *mem_reg);
46 static
47 int iser_fast_reg_mr(struct iscsi_iser_task *iser_task,
48 		     struct iser_data_buf *mem,
49 		     struct iser_reg_resources *rsc,
50 		     struct iser_mem_reg *mem_reg);
51 
52 static const struct iser_reg_ops fastreg_ops = {
53 	.alloc_reg_res	= iser_alloc_fastreg_pool,
54 	.free_reg_res	= iser_free_fastreg_pool,
55 	.reg_mem	= iser_fast_reg_mr,
56 	.unreg_mem	= iser_unreg_mem_fastreg,
57 	.reg_desc_get	= iser_reg_desc_get_fr,
58 	.reg_desc_put	= iser_reg_desc_put_fr,
59 };
60 
61 static const struct iser_reg_ops fmr_ops = {
62 	.alloc_reg_res	= iser_alloc_fmr_pool,
63 	.free_reg_res	= iser_free_fmr_pool,
64 	.reg_mem	= iser_fast_reg_fmr,
65 	.unreg_mem	= iser_unreg_mem_fmr,
66 	.reg_desc_get	= iser_reg_desc_get_fmr,
67 	.reg_desc_put	= iser_reg_desc_put_fmr,
68 };
69 
70 void iser_reg_comp(struct ib_cq *cq, struct ib_wc *wc)
71 {
72 	iser_err_comp(wc, "memreg");
73 }
74 
75 int iser_assign_reg_ops(struct iser_device *device)
76 {
77 	struct ib_device *ib_dev = device->ib_device;
78 
79 	/* Assign function handles  - based on FMR support */
80 	if (ib_dev->alloc_fmr && ib_dev->dealloc_fmr &&
81 	    ib_dev->map_phys_fmr && ib_dev->unmap_fmr) {
82 		iser_info("FMR supported, using FMR for registration\n");
83 		device->reg_ops = &fmr_ops;
84 	} else if (ib_dev->attrs.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) {
85 		iser_info("FastReg supported, using FastReg for registration\n");
86 		device->reg_ops = &fastreg_ops;
87 		device->remote_inv_sup = iser_always_reg;
88 	} else {
89 		iser_err("IB device does not support FMRs nor FastRegs, can't register memory\n");
90 		return -1;
91 	}
92 
93 	return 0;
94 }
95 
96 struct iser_fr_desc *
97 iser_reg_desc_get_fr(struct ib_conn *ib_conn)
98 {
99 	struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
100 	struct iser_fr_desc *desc;
101 	unsigned long flags;
102 
103 	spin_lock_irqsave(&fr_pool->lock, flags);
104 	desc = list_first_entry(&fr_pool->list,
105 				struct iser_fr_desc, list);
106 	list_del(&desc->list);
107 	spin_unlock_irqrestore(&fr_pool->lock, flags);
108 
109 	return desc;
110 }
111 
112 void
113 iser_reg_desc_put_fr(struct ib_conn *ib_conn,
114 		     struct iser_fr_desc *desc)
115 {
116 	struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
117 	unsigned long flags;
118 
119 	spin_lock_irqsave(&fr_pool->lock, flags);
120 	list_add(&desc->list, &fr_pool->list);
121 	spin_unlock_irqrestore(&fr_pool->lock, flags);
122 }
123 
124 struct iser_fr_desc *
125 iser_reg_desc_get_fmr(struct ib_conn *ib_conn)
126 {
127 	struct iser_fr_pool *fr_pool = &ib_conn->fr_pool;
128 
129 	return list_first_entry(&fr_pool->list,
130 				struct iser_fr_desc, list);
131 }
132 
133 void
134 iser_reg_desc_put_fmr(struct ib_conn *ib_conn,
135 		      struct iser_fr_desc *desc)
136 {
137 }
138 
139 static void iser_data_buf_dump(struct iser_data_buf *data,
140 			       struct ib_device *ibdev)
141 {
142 	struct scatterlist *sg;
143 	int i;
144 
145 	for_each_sg(data->sg, sg, data->dma_nents, i)
146 		iser_dbg("sg[%d] dma_addr:0x%lX page:0x%p "
147 			 "off:0x%x sz:0x%x dma_len:0x%x\n",
148 			 i, (unsigned long)ib_sg_dma_address(ibdev, sg),
149 			 sg_page(sg), sg->offset,
150 			 sg->length, ib_sg_dma_len(ibdev, sg));
151 }
152 
153 static void iser_dump_page_vec(struct iser_page_vec *page_vec)
154 {
155 	int i;
156 
157 	iser_err("page vec npages %d data length %lld\n",
158 		 page_vec->npages, page_vec->fake_mr.length);
159 	for (i = 0; i < page_vec->npages; i++)
160 		iser_err("vec[%d]: %llx\n", i, page_vec->pages[i]);
161 }
162 
163 int iser_dma_map_task_data(struct iscsi_iser_task *iser_task,
164 			    struct iser_data_buf *data,
165 			    enum iser_data_dir iser_dir,
166 			    enum dma_data_direction dma_dir)
167 {
168 	struct ib_device *dev;
169 
170 	iser_task->dir[iser_dir] = 1;
171 	dev = iser_task->iser_conn->ib_conn.device->ib_device;
172 
173 	data->dma_nents = ib_dma_map_sg(dev, data->sg, data->size, dma_dir);
174 	if (data->dma_nents == 0) {
175 		iser_err("dma_map_sg failed!!!\n");
176 		return -EINVAL;
177 	}
178 	return 0;
179 }
180 
181 void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task,
182 			      struct iser_data_buf *data,
183 			      enum dma_data_direction dir)
184 {
185 	struct ib_device *dev;
186 
187 	dev = iser_task->iser_conn->ib_conn.device->ib_device;
188 	ib_dma_unmap_sg(dev, data->sg, data->size, dir);
189 }
190 
191 static int
192 iser_reg_dma(struct iser_device *device, struct iser_data_buf *mem,
193 	     struct iser_mem_reg *reg)
194 {
195 	struct scatterlist *sg = mem->sg;
196 
197 	reg->sge.lkey = device->pd->local_dma_lkey;
198 	/*
199 	 * FIXME: rework the registration code path to differentiate
200 	 * rkey/lkey use cases
201 	 */
202 
203 	if (device->pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)
204 		reg->rkey = device->pd->unsafe_global_rkey;
205 	else
206 		reg->rkey = 0;
207 	reg->sge.addr = ib_sg_dma_address(device->ib_device, &sg[0]);
208 	reg->sge.length = ib_sg_dma_len(device->ib_device, &sg[0]);
209 
210 	iser_dbg("Single DMA entry: lkey=0x%x, rkey=0x%x, addr=0x%llx,"
211 		 " length=0x%x\n", reg->sge.lkey, reg->rkey,
212 		 reg->sge.addr, reg->sge.length);
213 
214 	return 0;
215 }
216 
217 static int iser_set_page(struct ib_mr *mr, u64 addr)
218 {
219 	struct iser_page_vec *page_vec =
220 		container_of(mr, struct iser_page_vec, fake_mr);
221 
222 	page_vec->pages[page_vec->npages++] = addr;
223 
224 	return 0;
225 }
226 
227 static
228 int iser_fast_reg_fmr(struct iscsi_iser_task *iser_task,
229 		      struct iser_data_buf *mem,
230 		      struct iser_reg_resources *rsc,
231 		      struct iser_mem_reg *reg)
232 {
233 	struct ib_conn *ib_conn = &iser_task->iser_conn->ib_conn;
234 	struct iser_device *device = ib_conn->device;
235 	struct iser_page_vec *page_vec = rsc->page_vec;
236 	struct ib_fmr_pool *fmr_pool = rsc->fmr_pool;
237 	struct ib_pool_fmr *fmr;
238 	int ret, plen;
239 
240 	page_vec->npages = 0;
241 	page_vec->fake_mr.page_size = SIZE_4K;
242 	plen = ib_sg_to_pages(&page_vec->fake_mr, mem->sg,
243 			      mem->size, NULL, iser_set_page);
244 	if (unlikely(plen < mem->size)) {
245 		iser_err("page vec too short to hold this SG\n");
246 		iser_data_buf_dump(mem, device->ib_device);
247 		iser_dump_page_vec(page_vec);
248 		return -EINVAL;
249 	}
250 
251 	fmr  = ib_fmr_pool_map_phys(fmr_pool, page_vec->pages,
252 				    page_vec->npages, page_vec->pages[0]);
253 	if (IS_ERR(fmr)) {
254 		ret = PTR_ERR(fmr);
255 		iser_err("ib_fmr_pool_map_phys failed: %d\n", ret);
256 		return ret;
257 	}
258 
259 	reg->sge.lkey = fmr->fmr->lkey;
260 	reg->rkey = fmr->fmr->rkey;
261 	reg->sge.addr = page_vec->fake_mr.iova;
262 	reg->sge.length = page_vec->fake_mr.length;
263 	reg->mem_h = fmr;
264 
265 	iser_dbg("fmr reg: lkey=0x%x, rkey=0x%x, addr=0x%llx,"
266 		 " length=0x%x\n", reg->sge.lkey, reg->rkey,
267 		 reg->sge.addr, reg->sge.length);
268 
269 	return 0;
270 }
271 
272 /**
273  * Unregister (previosuly registered using FMR) memory.
274  * If memory is non-FMR does nothing.
275  */
276 void iser_unreg_mem_fmr(struct iscsi_iser_task *iser_task,
277 			enum iser_data_dir cmd_dir)
278 {
279 	struct iser_mem_reg *reg = &iser_task->rdma_reg[cmd_dir];
280 	int ret;
281 
282 	if (!reg->mem_h)
283 		return;
284 
285 	iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n", reg->mem_h);
286 
287 	ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h);
288 	if (ret)
289 		iser_err("ib_fmr_pool_unmap failed %d\n", ret);
290 
291 	reg->mem_h = NULL;
292 }
293 
294 void iser_unreg_mem_fastreg(struct iscsi_iser_task *iser_task,
295 			    enum iser_data_dir cmd_dir)
296 {
297 	struct iser_device *device = iser_task->iser_conn->ib_conn.device;
298 	struct iser_mem_reg *reg = &iser_task->rdma_reg[cmd_dir];
299 
300 	if (!reg->mem_h)
301 		return;
302 
303 	device->reg_ops->reg_desc_put(&iser_task->iser_conn->ib_conn,
304 				     reg->mem_h);
305 	reg->mem_h = NULL;
306 }
307 
308 static void
309 iser_set_dif_domain(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs,
310 		    struct ib_sig_domain *domain)
311 {
312 	domain->sig_type = IB_SIG_TYPE_T10_DIF;
313 	domain->sig.dif.pi_interval = scsi_prot_interval(sc);
314 	domain->sig.dif.ref_tag = t10_pi_ref_tag(sc->request);
315 	/*
316 	 * At the moment we hard code those, but in the future
317 	 * we will take them from sc.
318 	 */
319 	domain->sig.dif.apptag_check_mask = 0xffff;
320 	domain->sig.dif.app_escape = true;
321 	domain->sig.dif.ref_escape = true;
322 	if (sc->prot_flags & SCSI_PROT_REF_INCREMENT)
323 		domain->sig.dif.ref_remap = true;
324 };
325 
326 static int
327 iser_set_sig_attrs(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs)
328 {
329 	switch (scsi_get_prot_op(sc)) {
330 	case SCSI_PROT_WRITE_INSERT:
331 	case SCSI_PROT_READ_STRIP:
332 		sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
333 		iser_set_dif_domain(sc, sig_attrs, &sig_attrs->wire);
334 		sig_attrs->wire.sig.dif.bg_type = IB_T10DIF_CRC;
335 		break;
336 	case SCSI_PROT_READ_INSERT:
337 	case SCSI_PROT_WRITE_STRIP:
338 		sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
339 		iser_set_dif_domain(sc, sig_attrs, &sig_attrs->mem);
340 		sig_attrs->mem.sig.dif.bg_type = sc->prot_flags & SCSI_PROT_IP_CHECKSUM ?
341 						IB_T10DIF_CSUM : IB_T10DIF_CRC;
342 		break;
343 	case SCSI_PROT_READ_PASS:
344 	case SCSI_PROT_WRITE_PASS:
345 		iser_set_dif_domain(sc, sig_attrs, &sig_attrs->wire);
346 		sig_attrs->wire.sig.dif.bg_type = IB_T10DIF_CRC;
347 		iser_set_dif_domain(sc, sig_attrs, &sig_attrs->mem);
348 		sig_attrs->mem.sig.dif.bg_type = sc->prot_flags & SCSI_PROT_IP_CHECKSUM ?
349 						IB_T10DIF_CSUM : IB_T10DIF_CRC;
350 		break;
351 	default:
352 		iser_err("Unsupported PI operation %d\n",
353 			 scsi_get_prot_op(sc));
354 		return -EINVAL;
355 	}
356 
357 	return 0;
358 }
359 
360 static inline void
361 iser_set_prot_checks(struct scsi_cmnd *sc, u8 *mask)
362 {
363 	*mask = 0;
364 	if (sc->prot_flags & SCSI_PROT_REF_CHECK)
365 		*mask |= IB_SIG_CHECK_REFTAG;
366 	if (sc->prot_flags & SCSI_PROT_GUARD_CHECK)
367 		*mask |= IB_SIG_CHECK_GUARD;
368 }
369 
370 static inline void
371 iser_inv_rkey(struct ib_send_wr *inv_wr,
372 	      struct ib_mr *mr,
373 	      struct ib_cqe *cqe)
374 {
375 	inv_wr->opcode = IB_WR_LOCAL_INV;
376 	inv_wr->wr_cqe = cqe;
377 	inv_wr->ex.invalidate_rkey = mr->rkey;
378 	inv_wr->send_flags = 0;
379 	inv_wr->num_sge = 0;
380 }
381 
382 static int
383 iser_reg_sig_mr(struct iscsi_iser_task *iser_task,
384 		struct iser_pi_context *pi_ctx,
385 		struct iser_mem_reg *data_reg,
386 		struct iser_mem_reg *prot_reg,
387 		struct iser_mem_reg *sig_reg)
388 {
389 	struct iser_tx_desc *tx_desc = &iser_task->desc;
390 	struct ib_sig_attrs *sig_attrs = &tx_desc->sig_attrs;
391 	struct ib_cqe *cqe = &iser_task->iser_conn->ib_conn.reg_cqe;
392 	struct ib_sig_handover_wr *wr;
393 	struct ib_mr *mr = pi_ctx->sig_mr;
394 	int ret;
395 
396 	memset(sig_attrs, 0, sizeof(*sig_attrs));
397 	ret = iser_set_sig_attrs(iser_task->sc, sig_attrs);
398 	if (ret)
399 		goto err;
400 
401 	iser_set_prot_checks(iser_task->sc, &sig_attrs->check_mask);
402 
403 	if (pi_ctx->sig_mr_valid)
404 		iser_inv_rkey(iser_tx_next_wr(tx_desc), mr, cqe);
405 
406 	ib_update_fast_reg_key(mr, ib_inc_rkey(mr->rkey));
407 
408 	wr = container_of(iser_tx_next_wr(tx_desc), struct ib_sig_handover_wr,
409 			  wr);
410 	wr->wr.opcode = IB_WR_REG_SIG_MR;
411 	wr->wr.wr_cqe = cqe;
412 	wr->wr.sg_list = &data_reg->sge;
413 	wr->wr.num_sge = 1;
414 	wr->wr.send_flags = 0;
415 	wr->sig_attrs = sig_attrs;
416 	wr->sig_mr = mr;
417 	if (scsi_prot_sg_count(iser_task->sc))
418 		wr->prot = &prot_reg->sge;
419 	else
420 		wr->prot = NULL;
421 	wr->access_flags = IB_ACCESS_LOCAL_WRITE |
422 			   IB_ACCESS_REMOTE_READ |
423 			   IB_ACCESS_REMOTE_WRITE;
424 	pi_ctx->sig_mr_valid = 1;
425 
426 	sig_reg->sge.lkey = mr->lkey;
427 	sig_reg->rkey = mr->rkey;
428 	sig_reg->sge.addr = 0;
429 	sig_reg->sge.length = scsi_transfer_length(iser_task->sc);
430 
431 	iser_dbg("lkey=0x%x rkey=0x%x addr=0x%llx length=%u\n",
432 		 sig_reg->sge.lkey, sig_reg->rkey, sig_reg->sge.addr,
433 		 sig_reg->sge.length);
434 err:
435 	return ret;
436 }
437 
438 static int iser_fast_reg_mr(struct iscsi_iser_task *iser_task,
439 			    struct iser_data_buf *mem,
440 			    struct iser_reg_resources *rsc,
441 			    struct iser_mem_reg *reg)
442 {
443 	struct iser_tx_desc *tx_desc = &iser_task->desc;
444 	struct ib_cqe *cqe = &iser_task->iser_conn->ib_conn.reg_cqe;
445 	struct ib_mr *mr = rsc->mr;
446 	struct ib_reg_wr *wr;
447 	int n;
448 
449 	if (rsc->mr_valid)
450 		iser_inv_rkey(iser_tx_next_wr(tx_desc), mr, cqe);
451 
452 	ib_update_fast_reg_key(mr, ib_inc_rkey(mr->rkey));
453 
454 	n = ib_map_mr_sg(mr, mem->sg, mem->size, NULL, SIZE_4K);
455 	if (unlikely(n != mem->size)) {
456 		iser_err("failed to map sg (%d/%d)\n",
457 			 n, mem->size);
458 		return n < 0 ? n : -EINVAL;
459 	}
460 
461 	wr = container_of(iser_tx_next_wr(tx_desc), struct ib_reg_wr, wr);
462 	wr->wr.opcode = IB_WR_REG_MR;
463 	wr->wr.wr_cqe = cqe;
464 	wr->wr.send_flags = 0;
465 	wr->wr.num_sge = 0;
466 	wr->mr = mr;
467 	wr->key = mr->rkey;
468 	wr->access = IB_ACCESS_LOCAL_WRITE  |
469 		     IB_ACCESS_REMOTE_WRITE |
470 		     IB_ACCESS_REMOTE_READ;
471 
472 	rsc->mr_valid = 1;
473 
474 	reg->sge.lkey = mr->lkey;
475 	reg->rkey = mr->rkey;
476 	reg->sge.addr = mr->iova;
477 	reg->sge.length = mr->length;
478 
479 	iser_dbg("lkey=0x%x rkey=0x%x addr=0x%llx length=0x%x\n",
480 		 reg->sge.lkey, reg->rkey, reg->sge.addr, reg->sge.length);
481 
482 	return 0;
483 }
484 
485 static int
486 iser_reg_prot_sg(struct iscsi_iser_task *task,
487 		 struct iser_data_buf *mem,
488 		 struct iser_fr_desc *desc,
489 		 bool use_dma_key,
490 		 struct iser_mem_reg *reg)
491 {
492 	struct iser_device *device = task->iser_conn->ib_conn.device;
493 
494 	if (use_dma_key)
495 		return iser_reg_dma(device, mem, reg);
496 
497 	return device->reg_ops->reg_mem(task, mem, &desc->pi_ctx->rsc, reg);
498 }
499 
500 static int
501 iser_reg_data_sg(struct iscsi_iser_task *task,
502 		 struct iser_data_buf *mem,
503 		 struct iser_fr_desc *desc,
504 		 bool use_dma_key,
505 		 struct iser_mem_reg *reg)
506 {
507 	struct iser_device *device = task->iser_conn->ib_conn.device;
508 
509 	if (use_dma_key)
510 		return iser_reg_dma(device, mem, reg);
511 
512 	return device->reg_ops->reg_mem(task, mem, &desc->rsc, reg);
513 }
514 
515 int iser_reg_rdma_mem(struct iscsi_iser_task *task,
516 		      enum iser_data_dir dir,
517 		      bool all_imm)
518 {
519 	struct ib_conn *ib_conn = &task->iser_conn->ib_conn;
520 	struct iser_device *device = ib_conn->device;
521 	struct iser_data_buf *mem = &task->data[dir];
522 	struct iser_mem_reg *reg = &task->rdma_reg[dir];
523 	struct iser_mem_reg *data_reg;
524 	struct iser_fr_desc *desc = NULL;
525 	bool use_dma_key;
526 	int err;
527 
528 	use_dma_key = mem->dma_nents == 1 && (all_imm || !iser_always_reg) &&
529 		      scsi_get_prot_op(task->sc) == SCSI_PROT_NORMAL;
530 
531 	if (!use_dma_key) {
532 		desc = device->reg_ops->reg_desc_get(ib_conn);
533 		reg->mem_h = desc;
534 	}
535 
536 	if (scsi_get_prot_op(task->sc) == SCSI_PROT_NORMAL)
537 		data_reg = reg;
538 	else
539 		data_reg = &task->desc.data_reg;
540 
541 	err = iser_reg_data_sg(task, mem, desc, use_dma_key, data_reg);
542 	if (unlikely(err))
543 		goto err_reg;
544 
545 	if (scsi_get_prot_op(task->sc) != SCSI_PROT_NORMAL) {
546 		struct iser_mem_reg *prot_reg = &task->desc.prot_reg;
547 
548 		if (scsi_prot_sg_count(task->sc)) {
549 			mem = &task->prot[dir];
550 			err = iser_reg_prot_sg(task, mem, desc,
551 					       use_dma_key, prot_reg);
552 			if (unlikely(err))
553 				goto err_reg;
554 		}
555 
556 		err = iser_reg_sig_mr(task, desc->pi_ctx, data_reg,
557 				      prot_reg, reg);
558 		if (unlikely(err))
559 			goto err_reg;
560 
561 		desc->pi_ctx->sig_protected = 1;
562 	}
563 
564 	return 0;
565 
566 err_reg:
567 	if (desc)
568 		device->reg_ops->reg_desc_put(ib_conn, desc);
569 
570 	return err;
571 }
572 
573 void iser_unreg_rdma_mem(struct iscsi_iser_task *task,
574 			 enum iser_data_dir dir)
575 {
576 	struct iser_device *device = task->iser_conn->ib_conn.device;
577 
578 	device->reg_ops->unreg_mem(task, dir);
579 }
580