xref: /linux/drivers/target/target_core_xcopy.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*******************************************************************************
2  * Filename: target_core_xcopy.c
3  *
4  * This file contains support for SPC-4 Extended-Copy offload with generic
5  * TCM backends.
6  *
7  * Copyright (c) 2011-2013 Datera, Inc. All rights reserved.
8  *
9  * Author:
10  * Nicholas A. Bellinger <nab@daterainc.com>
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  ******************************************************************************/
23 
24 #include <linux/slab.h>
25 #include <linux/spinlock.h>
26 #include <linux/list.h>
27 #include <linux/configfs.h>
28 #include <linux/ratelimit.h>
29 #include <scsi/scsi_proto.h>
30 #include <asm/unaligned.h>
31 
32 #include <target/target_core_base.h>
33 #include <target/target_core_backend.h>
34 #include <target/target_core_fabric.h>
35 
36 #include "target_core_internal.h"
37 #include "target_core_pr.h"
38 #include "target_core_ua.h"
39 #include "target_core_xcopy.h"
40 
41 static struct workqueue_struct *xcopy_wq = NULL;
42 
43 static int target_xcopy_gen_naa_ieee(struct se_device *dev, unsigned char *buf)
44 {
45 	int off = 0;
46 
47 	buf[off++] = (0x6 << 4);
48 	buf[off++] = 0x01;
49 	buf[off++] = 0x40;
50 	buf[off] = (0x5 << 4);
51 
52 	spc_parse_naa_6h_vendor_specific(dev, &buf[off]);
53 	return 0;
54 }
55 
56 static int target_xcopy_locate_se_dev_e4(const unsigned char *dev_wwn,
57 					struct se_device **found_dev)
58 {
59 	struct se_device *se_dev;
60 	unsigned char tmp_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN];
61 	int rc;
62 
63 	mutex_lock(&g_device_mutex);
64 	list_for_each_entry(se_dev, &g_device_list, g_dev_node) {
65 
66 		if (!se_dev->dev_attrib.emulate_3pc)
67 			continue;
68 
69 		memset(&tmp_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
70 		target_xcopy_gen_naa_ieee(se_dev, &tmp_dev_wwn[0]);
71 
72 		rc = memcmp(&tmp_dev_wwn[0], dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN);
73 		if (rc != 0)
74 			continue;
75 
76 		*found_dev = se_dev;
77 		pr_debug("XCOPY 0xe4: located se_dev: %p\n", se_dev);
78 
79 		rc = target_depend_item(&se_dev->dev_group.cg_item);
80 		if (rc != 0) {
81 			pr_err("configfs_depend_item attempt failed:"
82 				" %d for se_dev: %p\n", rc, se_dev);
83 			mutex_unlock(&g_device_mutex);
84 			return rc;
85 		}
86 
87 		pr_debug("Called configfs_depend_item for se_dev: %p"
88 			" se_dev->se_dev_group: %p\n", se_dev,
89 			&se_dev->dev_group);
90 
91 		mutex_unlock(&g_device_mutex);
92 		return 0;
93 	}
94 	mutex_unlock(&g_device_mutex);
95 
96 	pr_debug_ratelimited("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n");
97 	return -EINVAL;
98 }
99 
100 static int target_xcopy_parse_tiddesc_e4(struct se_cmd *se_cmd, struct xcopy_op *xop,
101 				unsigned char *p, unsigned short cscd_index)
102 {
103 	unsigned char *desc = p;
104 	unsigned short ript;
105 	u8 desig_len;
106 	/*
107 	 * Extract RELATIVE INITIATOR PORT IDENTIFIER
108 	 */
109 	ript = get_unaligned_be16(&desc[2]);
110 	pr_debug("XCOPY 0xe4: RELATIVE INITIATOR PORT IDENTIFIER: %hu\n", ript);
111 	/*
112 	 * Check for supported code set, association, and designator type
113 	 */
114 	if ((desc[4] & 0x0f) != 0x1) {
115 		pr_err("XCOPY 0xe4: code set of non binary type not supported\n");
116 		return -EINVAL;
117 	}
118 	if ((desc[5] & 0x30) != 0x00) {
119 		pr_err("XCOPY 0xe4: association other than LUN not supported\n");
120 		return -EINVAL;
121 	}
122 	if ((desc[5] & 0x0f) != 0x3) {
123 		pr_err("XCOPY 0xe4: designator type unsupported: 0x%02x\n",
124 				(desc[5] & 0x0f));
125 		return -EINVAL;
126 	}
127 	/*
128 	 * Check for matching 16 byte length for NAA IEEE Registered Extended
129 	 * Assigned designator
130 	 */
131 	desig_len = desc[7];
132 	if (desig_len != 16) {
133 		pr_err("XCOPY 0xe4: invalid desig_len: %d\n", (int)desig_len);
134 		return -EINVAL;
135 	}
136 	pr_debug("XCOPY 0xe4: desig_len: %d\n", (int)desig_len);
137 	/*
138 	 * Check for NAA IEEE Registered Extended Assigned header..
139 	 */
140 	if ((desc[8] & 0xf0) != 0x60) {
141 		pr_err("XCOPY 0xe4: Unsupported DESIGNATOR TYPE: 0x%02x\n",
142 					(desc[8] & 0xf0));
143 		return -EINVAL;
144 	}
145 
146 	if (cscd_index != xop->stdi && cscd_index != xop->dtdi) {
147 		pr_debug("XCOPY 0xe4: ignoring CSCD entry %d - neither src nor "
148 			 "dest\n", cscd_index);
149 		return 0;
150 	}
151 
152 	if (cscd_index == xop->stdi) {
153 		memcpy(&xop->src_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
154 		/*
155 		 * Determine if the source designator matches the local device
156 		 */
157 		if (!memcmp(&xop->local_dev_wwn[0], &xop->src_tid_wwn[0],
158 				XCOPY_NAA_IEEE_REGEX_LEN)) {
159 			xop->op_origin = XCOL_SOURCE_RECV_OP;
160 			xop->src_dev = se_cmd->se_dev;
161 			pr_debug("XCOPY 0xe4: Set xop->src_dev %p from source"
162 					" received xop\n", xop->src_dev);
163 		}
164 	}
165 
166 	if (cscd_index == xop->dtdi) {
167 		memcpy(&xop->dst_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
168 		/*
169 		 * Determine if the destination designator matches the local
170 		 * device. If @cscd_index corresponds to both source (stdi) and
171 		 * destination (dtdi), or dtdi comes after stdi, then
172 		 * XCOL_DEST_RECV_OP wins.
173 		 */
174 		if (!memcmp(&xop->local_dev_wwn[0], &xop->dst_tid_wwn[0],
175 				XCOPY_NAA_IEEE_REGEX_LEN)) {
176 			xop->op_origin = XCOL_DEST_RECV_OP;
177 			xop->dst_dev = se_cmd->se_dev;
178 			pr_debug("XCOPY 0xe4: Set xop->dst_dev: %p from destination"
179 				" received xop\n", xop->dst_dev);
180 		}
181 	}
182 
183 	return 0;
184 }
185 
186 static int target_xcopy_parse_target_descriptors(struct se_cmd *se_cmd,
187 				struct xcopy_op *xop, unsigned char *p,
188 				unsigned short tdll, sense_reason_t *sense_ret)
189 {
190 	struct se_device *local_dev = se_cmd->se_dev;
191 	unsigned char *desc = p;
192 	int offset = tdll % XCOPY_TARGET_DESC_LEN, rc;
193 	unsigned short cscd_index = 0;
194 	unsigned short start = 0;
195 
196 	*sense_ret = TCM_INVALID_PARAMETER_LIST;
197 
198 	if (offset != 0) {
199 		pr_err("XCOPY target descriptor list length is not"
200 			" multiple of %d\n", XCOPY_TARGET_DESC_LEN);
201 		*sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
202 		return -EINVAL;
203 	}
204 	if (tdll > RCR_OP_MAX_TARGET_DESC_COUNT * XCOPY_TARGET_DESC_LEN) {
205 		pr_err("XCOPY target descriptor supports a maximum"
206 			" two src/dest descriptors, tdll: %hu too large..\n", tdll);
207 		/* spc4r37 6.4.3.4 CSCD DESCRIPTOR LIST LENGTH field */
208 		*sense_ret = TCM_TOO_MANY_TARGET_DESCS;
209 		return -EINVAL;
210 	}
211 	/*
212 	 * Generate an IEEE Registered Extended designator based upon the
213 	 * se_device the XCOPY was received upon..
214 	 */
215 	memset(&xop->local_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
216 	target_xcopy_gen_naa_ieee(local_dev, &xop->local_dev_wwn[0]);
217 
218 	while (start < tdll) {
219 		/*
220 		 * Check target descriptor identification with 0xE4 type, and
221 		 * compare the current index with the CSCD descriptor IDs in
222 		 * the segment descriptor. Use VPD 0x83 WWPN matching ..
223 		 */
224 		switch (desc[0]) {
225 		case 0xe4:
226 			rc = target_xcopy_parse_tiddesc_e4(se_cmd, xop,
227 							&desc[0], cscd_index);
228 			if (rc != 0)
229 				goto out;
230 			start += XCOPY_TARGET_DESC_LEN;
231 			desc += XCOPY_TARGET_DESC_LEN;
232 			cscd_index++;
233 			break;
234 		default:
235 			pr_err("XCOPY unsupported descriptor type code:"
236 					" 0x%02x\n", desc[0]);
237 			*sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
238 			goto out;
239 		}
240 	}
241 
242 	switch (xop->op_origin) {
243 	case XCOL_SOURCE_RECV_OP:
244 		rc = target_xcopy_locate_se_dev_e4(xop->dst_tid_wwn,
245 						&xop->dst_dev);
246 		break;
247 	case XCOL_DEST_RECV_OP:
248 		rc = target_xcopy_locate_se_dev_e4(xop->src_tid_wwn,
249 						&xop->src_dev);
250 		break;
251 	default:
252 		pr_err("XCOPY CSCD descriptor IDs not found in CSCD list - "
253 			"stdi: %hu dtdi: %hu\n", xop->stdi, xop->dtdi);
254 		rc = -EINVAL;
255 		break;
256 	}
257 	/*
258 	 * If a matching IEEE NAA 0x83 descriptor for the requested device
259 	 * is not located on this node, return COPY_ABORTED with ASQ/ASQC
260 	 * 0x0d/0x02 - COPY_TARGET_DEVICE_NOT_REACHABLE to request the
261 	 * initiator to fall back to normal copy method.
262 	 */
263 	if (rc < 0) {
264 		*sense_ret = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
265 		goto out;
266 	}
267 
268 	pr_debug("XCOPY TGT desc: Source dev: %p NAA IEEE WWN: 0x%16phN\n",
269 		 xop->src_dev, &xop->src_tid_wwn[0]);
270 	pr_debug("XCOPY TGT desc: Dest dev: %p NAA IEEE WWN: 0x%16phN\n",
271 		 xop->dst_dev, &xop->dst_tid_wwn[0]);
272 
273 	return cscd_index;
274 
275 out:
276 	return -EINVAL;
277 }
278 
279 static int target_xcopy_parse_segdesc_02(struct se_cmd *se_cmd, struct xcopy_op *xop,
280 					unsigned char *p)
281 {
282 	unsigned char *desc = p;
283 	int dc = (desc[1] & 0x02);
284 	unsigned short desc_len;
285 
286 	desc_len = get_unaligned_be16(&desc[2]);
287 	if (desc_len != 0x18) {
288 		pr_err("XCOPY segment desc 0x02: Illegal desc_len:"
289 				" %hu\n", desc_len);
290 		return -EINVAL;
291 	}
292 
293 	xop->stdi = get_unaligned_be16(&desc[4]);
294 	xop->dtdi = get_unaligned_be16(&desc[6]);
295 
296 	if (xop->stdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX ||
297 	    xop->dtdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX) {
298 		pr_err("XCOPY segment desc 0x02: unsupported CSCD ID > 0x%x; stdi: %hu dtdi: %hu\n",
299 			XCOPY_CSCD_DESC_ID_LIST_OFF_MAX, xop->stdi, xop->dtdi);
300 		return -EINVAL;
301 	}
302 
303 	pr_debug("XCOPY seg desc 0x02: desc_len: %hu stdi: %hu dtdi: %hu, DC: %d\n",
304 		desc_len, xop->stdi, xop->dtdi, dc);
305 
306 	xop->nolb = get_unaligned_be16(&desc[10]);
307 	xop->src_lba = get_unaligned_be64(&desc[12]);
308 	xop->dst_lba = get_unaligned_be64(&desc[20]);
309 	pr_debug("XCOPY seg desc 0x02: nolb: %hu src_lba: %llu dst_lba: %llu\n",
310 		xop->nolb, (unsigned long long)xop->src_lba,
311 		(unsigned long long)xop->dst_lba);
312 
313 	if (dc != 0) {
314 		xop->dbl = (desc[29] & 0xff) << 16;
315 		xop->dbl |= (desc[30] & 0xff) << 8;
316 		xop->dbl |= desc[31] & 0xff;
317 
318 		pr_debug("XCOPY seg desc 0x02: DC=1 w/ dbl: %u\n", xop->dbl);
319 	}
320 	return 0;
321 }
322 
323 static int target_xcopy_parse_segment_descriptors(struct se_cmd *se_cmd,
324 				struct xcopy_op *xop, unsigned char *p,
325 				unsigned int sdll, sense_reason_t *sense_ret)
326 {
327 	unsigned char *desc = p;
328 	unsigned int start = 0;
329 	int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
330 
331 	*sense_ret = TCM_INVALID_PARAMETER_LIST;
332 
333 	if (offset != 0) {
334 		pr_err("XCOPY segment descriptor list length is not"
335 			" multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
336 		*sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
337 		return -EINVAL;
338 	}
339 	if (sdll > RCR_OP_MAX_SG_DESC_COUNT * XCOPY_SEGMENT_DESC_LEN) {
340 		pr_err("XCOPY supports %u segment descriptor(s), sdll: %u too"
341 			" large..\n", RCR_OP_MAX_SG_DESC_COUNT, sdll);
342 		/* spc4r37 6.4.3.5 SEGMENT DESCRIPTOR LIST LENGTH field */
343 		*sense_ret = TCM_TOO_MANY_SEGMENT_DESCS;
344 		return -EINVAL;
345 	}
346 
347 	while (start < sdll) {
348 		/*
349 		 * Check segment descriptor type code for block -> block
350 		 */
351 		switch (desc[0]) {
352 		case 0x02:
353 			rc = target_xcopy_parse_segdesc_02(se_cmd, xop, desc);
354 			if (rc < 0)
355 				goto out;
356 
357 			ret++;
358 			start += XCOPY_SEGMENT_DESC_LEN;
359 			desc += XCOPY_SEGMENT_DESC_LEN;
360 			break;
361 		default:
362 			pr_err("XCOPY unsupported segment descriptor"
363 				"type: 0x%02x\n", desc[0]);
364 			*sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
365 			goto out;
366 		}
367 	}
368 
369 	return ret;
370 
371 out:
372 	return -EINVAL;
373 }
374 
375 /*
376  * Start xcopy_pt ops
377  */
378 
379 struct xcopy_pt_cmd {
380 	bool remote_port;
381 	struct se_cmd se_cmd;
382 	struct xcopy_op *xcopy_op;
383 	struct completion xpt_passthrough_sem;
384 	unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
385 };
386 
387 struct se_portal_group xcopy_pt_tpg;
388 static struct se_session xcopy_pt_sess;
389 static struct se_node_acl xcopy_pt_nacl;
390 
391 static char *xcopy_pt_get_fabric_name(void)
392 {
393         return "xcopy-pt";
394 }
395 
396 static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
397 {
398         return 0;
399 }
400 
401 static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
402 {
403 	struct se_device *remote_dev;
404 
405 	if (xop->op_origin == XCOL_SOURCE_RECV_OP)
406 		remote_dev = xop->dst_dev;
407 	else
408 		remote_dev = xop->src_dev;
409 
410 	pr_debug("Calling configfs_undepend_item for"
411 		  " remote_dev: %p remote_dev->dev_group: %p\n",
412 		  remote_dev, &remote_dev->dev_group.cg_item);
413 
414 	target_undepend_item(&remote_dev->dev_group.cg_item);
415 }
416 
417 static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
418 {
419 	struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
420 				struct xcopy_pt_cmd, se_cmd);
421 
422 	kfree(xpt_cmd);
423 }
424 
425 static int xcopy_pt_check_stop_free(struct se_cmd *se_cmd)
426 {
427 	struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
428 				struct xcopy_pt_cmd, se_cmd);
429 
430 	complete(&xpt_cmd->xpt_passthrough_sem);
431 	return 0;
432 }
433 
434 static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
435 {
436 	return 0;
437 }
438 
439 static int xcopy_pt_write_pending_status(struct se_cmd *se_cmd)
440 {
441 	return 0;
442 }
443 
444 static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
445 {
446 	return 0;
447 }
448 
449 static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
450 {
451 	return 0;
452 }
453 
454 static const struct target_core_fabric_ops xcopy_pt_tfo = {
455 	.get_fabric_name	= xcopy_pt_get_fabric_name,
456 	.get_cmd_state		= xcopy_pt_get_cmd_state,
457 	.release_cmd		= xcopy_pt_release_cmd,
458 	.check_stop_free	= xcopy_pt_check_stop_free,
459 	.write_pending		= xcopy_pt_write_pending,
460 	.write_pending_status	= xcopy_pt_write_pending_status,
461 	.queue_data_in		= xcopy_pt_queue_data_in,
462 	.queue_status		= xcopy_pt_queue_status,
463 };
464 
465 /*
466  * End xcopy_pt_ops
467  */
468 
469 int target_xcopy_setup_pt(void)
470 {
471 	xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
472 	if (!xcopy_wq) {
473 		pr_err("Unable to allocate xcopy_wq\n");
474 		return -ENOMEM;
475 	}
476 
477 	memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
478 	INIT_LIST_HEAD(&xcopy_pt_tpg.se_tpg_node);
479 	INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
480 	INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
481 
482 	xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
483 
484 	memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
485 	INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
486 	INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
487 	memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
488 	INIT_LIST_HEAD(&xcopy_pt_sess.sess_list);
489 	INIT_LIST_HEAD(&xcopy_pt_sess.sess_acl_list);
490 	INIT_LIST_HEAD(&xcopy_pt_sess.sess_cmd_list);
491 	spin_lock_init(&xcopy_pt_sess.sess_cmd_lock);
492 
493 	xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
494 	xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
495 
496 	xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
497 	xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
498 
499 	return 0;
500 }
501 
502 void target_xcopy_release_pt(void)
503 {
504 	if (xcopy_wq)
505 		destroy_workqueue(xcopy_wq);
506 }
507 
508 static void target_xcopy_setup_pt_port(
509 	struct xcopy_pt_cmd *xpt_cmd,
510 	struct xcopy_op *xop,
511 	bool remote_port)
512 {
513 	struct se_cmd *ec_cmd = xop->xop_se_cmd;
514 	struct se_cmd *pt_cmd = &xpt_cmd->se_cmd;
515 
516 	if (xop->op_origin == XCOL_SOURCE_RECV_OP) {
517 		/*
518 		 * Honor destination port reservations for X-COPY PUSH emulation
519 		 * when CDB is received on local source port, and READs blocks to
520 		 * WRITE on remote destination port.
521 		 */
522 		if (remote_port) {
523 			xpt_cmd->remote_port = remote_port;
524 		} else {
525 			pt_cmd->se_lun = ec_cmd->se_lun;
526 			pt_cmd->se_dev = ec_cmd->se_dev;
527 
528 			pr_debug("Honoring local SRC port from ec_cmd->se_dev:"
529 				" %p\n", pt_cmd->se_dev);
530 			pt_cmd->se_lun = ec_cmd->se_lun;
531 			pr_debug("Honoring local SRC port from ec_cmd->se_lun: %p\n",
532 				pt_cmd->se_lun);
533 		}
534 	} else {
535 		/*
536 		 * Honor source port reservation for X-COPY PULL emulation
537 		 * when CDB is received on local desintation port, and READs
538 		 * blocks from the remote source port to WRITE on local
539 		 * destination port.
540 		 */
541 		if (remote_port) {
542 			xpt_cmd->remote_port = remote_port;
543 		} else {
544 			pt_cmd->se_lun = ec_cmd->se_lun;
545 			pt_cmd->se_dev = ec_cmd->se_dev;
546 
547 			pr_debug("Honoring local DST port from ec_cmd->se_dev:"
548 				" %p\n", pt_cmd->se_dev);
549 			pt_cmd->se_lun = ec_cmd->se_lun;
550 			pr_debug("Honoring local DST port from ec_cmd->se_lun: %p\n",
551 				pt_cmd->se_lun);
552 		}
553 	}
554 }
555 
556 static void target_xcopy_init_pt_lun(struct se_device *se_dev,
557 		struct se_cmd *pt_cmd, bool remote_port)
558 {
559 	/*
560 	 * Don't allocate + init an pt_cmd->se_lun if honoring local port for
561 	 * reservations.  The pt_cmd->se_lun pointer will be setup from within
562 	 * target_xcopy_setup_pt_port()
563 	 */
564 	if (remote_port) {
565 		pr_debug("Setup emulated se_dev: %p from se_dev\n",
566 			pt_cmd->se_dev);
567 		pt_cmd->se_lun = &se_dev->xcopy_lun;
568 		pt_cmd->se_dev = se_dev;
569 	}
570 
571 	pt_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
572 }
573 
574 static int target_xcopy_setup_pt_cmd(
575 	struct xcopy_pt_cmd *xpt_cmd,
576 	struct xcopy_op *xop,
577 	struct se_device *se_dev,
578 	unsigned char *cdb,
579 	bool remote_port,
580 	bool alloc_mem)
581 {
582 	struct se_cmd *cmd = &xpt_cmd->se_cmd;
583 	sense_reason_t sense_rc;
584 	int ret = 0, rc;
585 	/*
586 	 * Setup LUN+port to honor reservations based upon xop->op_origin for
587 	 * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
588 	 */
589 	target_xcopy_init_pt_lun(se_dev, cmd, remote_port);
590 
591 	xpt_cmd->xcopy_op = xop;
592 	target_xcopy_setup_pt_port(xpt_cmd, xop, remote_port);
593 
594 	cmd->tag = 0;
595 	sense_rc = target_setup_cmd_from_cdb(cmd, cdb);
596 	if (sense_rc) {
597 		ret = -EINVAL;
598 		goto out;
599 	}
600 
601 	if (alloc_mem) {
602 		rc = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
603 				      cmd->data_length, false, false);
604 		if (rc < 0) {
605 			ret = rc;
606 			goto out;
607 		}
608 		/*
609 		 * Set this bit so that transport_free_pages() allows the
610 		 * caller to release SGLs + physical memory allocated by
611 		 * transport_generic_get_mem()..
612 		 */
613 		cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
614 	} else {
615 		/*
616 		 * Here the previously allocated SGLs for the internal READ
617 		 * are mapped zero-copy to the internal WRITE.
618 		 */
619 		sense_rc = transport_generic_map_mem_to_cmd(cmd,
620 					xop->xop_data_sg, xop->xop_data_nents,
621 					NULL, 0);
622 		if (sense_rc) {
623 			ret = -EINVAL;
624 			goto out;
625 		}
626 
627 		pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
628 			 " %u\n", cmd->t_data_sg, cmd->t_data_nents);
629 	}
630 
631 	return 0;
632 
633 out:
634 	return ret;
635 }
636 
637 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
638 {
639 	struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
640 	sense_reason_t sense_rc;
641 
642 	sense_rc = transport_generic_new_cmd(se_cmd);
643 	if (sense_rc)
644 		return -EINVAL;
645 
646 	if (se_cmd->data_direction == DMA_TO_DEVICE)
647 		target_execute_cmd(se_cmd);
648 
649 	wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
650 
651 	pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
652 			se_cmd->scsi_status);
653 
654 	return (se_cmd->scsi_status) ? -EINVAL : 0;
655 }
656 
657 static int target_xcopy_read_source(
658 	struct se_cmd *ec_cmd,
659 	struct xcopy_op *xop,
660 	struct se_device *src_dev,
661 	sector_t src_lba,
662 	u32 src_sectors)
663 {
664 	struct xcopy_pt_cmd *xpt_cmd;
665 	struct se_cmd *se_cmd;
666 	u32 length = (src_sectors * src_dev->dev_attrib.block_size);
667 	int rc;
668 	unsigned char cdb[16];
669 	bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
670 
671 	xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
672 	if (!xpt_cmd) {
673 		pr_err("Unable to allocate xcopy_pt_cmd\n");
674 		return -ENOMEM;
675 	}
676 	init_completion(&xpt_cmd->xpt_passthrough_sem);
677 	se_cmd = &xpt_cmd->se_cmd;
678 
679 	memset(&cdb[0], 0, 16);
680 	cdb[0] = READ_16;
681 	put_unaligned_be64(src_lba, &cdb[2]);
682 	put_unaligned_be32(src_sectors, &cdb[10]);
683 	pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
684 		(unsigned long long)src_lba, src_sectors, length);
685 
686 	transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
687 			      DMA_FROM_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
688 	xop->src_pt_cmd = xpt_cmd;
689 
690 	rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, src_dev, &cdb[0],
691 				remote_port, true);
692 	if (rc < 0) {
693 		ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
694 		transport_generic_free_cmd(se_cmd, 0);
695 		return rc;
696 	}
697 
698 	xop->xop_data_sg = se_cmd->t_data_sg;
699 	xop->xop_data_nents = se_cmd->t_data_nents;
700 	pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
701 		" memory\n", xop->xop_data_sg, xop->xop_data_nents);
702 
703 	rc = target_xcopy_issue_pt_cmd(xpt_cmd);
704 	if (rc < 0) {
705 		ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
706 		transport_generic_free_cmd(se_cmd, 0);
707 		return rc;
708 	}
709 	/*
710 	 * Clear off the allocated t_data_sg, that has been saved for
711 	 * zero-copy WRITE submission reuse in struct xcopy_op..
712 	 */
713 	se_cmd->t_data_sg = NULL;
714 	se_cmd->t_data_nents = 0;
715 
716 	return 0;
717 }
718 
719 static int target_xcopy_write_destination(
720 	struct se_cmd *ec_cmd,
721 	struct xcopy_op *xop,
722 	struct se_device *dst_dev,
723 	sector_t dst_lba,
724 	u32 dst_sectors)
725 {
726 	struct xcopy_pt_cmd *xpt_cmd;
727 	struct se_cmd *se_cmd;
728 	u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
729 	int rc;
730 	unsigned char cdb[16];
731 	bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
732 
733 	xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
734 	if (!xpt_cmd) {
735 		pr_err("Unable to allocate xcopy_pt_cmd\n");
736 		return -ENOMEM;
737 	}
738 	init_completion(&xpt_cmd->xpt_passthrough_sem);
739 	se_cmd = &xpt_cmd->se_cmd;
740 
741 	memset(&cdb[0], 0, 16);
742 	cdb[0] = WRITE_16;
743 	put_unaligned_be64(dst_lba, &cdb[2]);
744 	put_unaligned_be32(dst_sectors, &cdb[10]);
745 	pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
746 		(unsigned long long)dst_lba, dst_sectors, length);
747 
748 	transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
749 			      DMA_TO_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
750 	xop->dst_pt_cmd = xpt_cmd;
751 
752 	rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, dst_dev, &cdb[0],
753 				remote_port, false);
754 	if (rc < 0) {
755 		struct se_cmd *src_cmd = &xop->src_pt_cmd->se_cmd;
756 		ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
757 		/*
758 		 * If the failure happened before the t_mem_list hand-off in
759 		 * target_xcopy_setup_pt_cmd(), Reset memory + clear flag so that
760 		 * core releases this memory on error during X-COPY WRITE I/O.
761 		 */
762 		src_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
763 		src_cmd->t_data_sg = xop->xop_data_sg;
764 		src_cmd->t_data_nents = xop->xop_data_nents;
765 
766 		transport_generic_free_cmd(se_cmd, 0);
767 		return rc;
768 	}
769 
770 	rc = target_xcopy_issue_pt_cmd(xpt_cmd);
771 	if (rc < 0) {
772 		ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
773 		se_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
774 		transport_generic_free_cmd(se_cmd, 0);
775 		return rc;
776 	}
777 
778 	return 0;
779 }
780 
781 static void target_xcopy_do_work(struct work_struct *work)
782 {
783 	struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
784 	struct se_device *src_dev = xop->src_dev, *dst_dev = xop->dst_dev;
785 	struct se_cmd *ec_cmd = xop->xop_se_cmd;
786 	sector_t src_lba = xop->src_lba, dst_lba = xop->dst_lba, end_lba;
787 	unsigned int max_sectors;
788 	int rc;
789 	unsigned short nolb = xop->nolb, cur_nolb, max_nolb, copied_nolb = 0;
790 
791 	end_lba = src_lba + nolb;
792 	/*
793 	 * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
794 	 * smallest max_sectors between src_dev + dev_dev, or
795 	 */
796 	max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
797 			  dst_dev->dev_attrib.hw_max_sectors);
798 	max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
799 
800 	max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
801 
802 	pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
803 			nolb, max_nolb, (unsigned long long)end_lba);
804 	pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
805 			(unsigned long long)src_lba, (unsigned long long)dst_lba);
806 
807 	while (src_lba < end_lba) {
808 		cur_nolb = min(nolb, max_nolb);
809 
810 		pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
811 			" cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
812 
813 		rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
814 		if (rc < 0)
815 			goto out;
816 
817 		src_lba += cur_nolb;
818 		pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
819 				(unsigned long long)src_lba);
820 
821 		pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
822 			" cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
823 
824 		rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
825 						dst_lba, cur_nolb);
826 		if (rc < 0) {
827 			transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
828 			goto out;
829 		}
830 
831 		dst_lba += cur_nolb;
832 		pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
833 				(unsigned long long)dst_lba);
834 
835 		copied_nolb += cur_nolb;
836 		nolb -= cur_nolb;
837 
838 		transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
839 		xop->dst_pt_cmd->se_cmd.se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
840 
841 		transport_generic_free_cmd(&xop->dst_pt_cmd->se_cmd, 0);
842 	}
843 
844 	xcopy_pt_undepend_remotedev(xop);
845 	kfree(xop);
846 
847 	pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
848 		(unsigned long long)src_lba, (unsigned long long)dst_lba);
849 	pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
850 		copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
851 
852 	pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
853 	target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
854 	return;
855 
856 out:
857 	xcopy_pt_undepend_remotedev(xop);
858 	kfree(xop);
859 	/*
860 	 * Don't override an error scsi status if it has already been set
861 	 */
862 	if (ec_cmd->scsi_status == SAM_STAT_GOOD) {
863 		pr_warn_ratelimited("target_xcopy_do_work: rc: %d, Setting X-COPY"
864 			" CHECK_CONDITION -> sending response\n", rc);
865 		ec_cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
866 	}
867 	target_complete_cmd(ec_cmd, ec_cmd->scsi_status);
868 }
869 
870 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
871 {
872 	struct se_device *dev = se_cmd->se_dev;
873 	struct xcopy_op *xop = NULL;
874 	unsigned char *p = NULL, *seg_desc;
875 	unsigned int list_id, list_id_usage, sdll, inline_dl, sa;
876 	sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
877 	int rc;
878 	unsigned short tdll;
879 
880 	if (!dev->dev_attrib.emulate_3pc) {
881 		pr_err("EXTENDED_COPY operation explicitly disabled\n");
882 		return TCM_UNSUPPORTED_SCSI_OPCODE;
883 	}
884 
885 	sa = se_cmd->t_task_cdb[1] & 0x1f;
886 	if (sa != 0x00) {
887 		pr_err("EXTENDED_COPY(LID4) not supported\n");
888 		return TCM_UNSUPPORTED_SCSI_OPCODE;
889 	}
890 
891 	if (se_cmd->data_length == 0) {
892 		target_complete_cmd(se_cmd, SAM_STAT_GOOD);
893 		return TCM_NO_SENSE;
894 	}
895 	if (se_cmd->data_length < XCOPY_HDR_LEN) {
896 		pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
897 				se_cmd->data_length, XCOPY_HDR_LEN);
898 		return TCM_PARAMETER_LIST_LENGTH_ERROR;
899 	}
900 
901 	xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
902 	if (!xop) {
903 		pr_err("Unable to allocate xcopy_op\n");
904 		return TCM_OUT_OF_RESOURCES;
905 	}
906 	xop->xop_se_cmd = se_cmd;
907 
908 	p = transport_kmap_data_sg(se_cmd);
909 	if (!p) {
910 		pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
911 		kfree(xop);
912 		return TCM_OUT_OF_RESOURCES;
913 	}
914 
915 	list_id = p[0];
916 	list_id_usage = (p[1] & 0x18) >> 3;
917 
918 	/*
919 	 * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
920 	 */
921 	tdll = get_unaligned_be16(&p[2]);
922 	sdll = get_unaligned_be32(&p[8]);
923 	if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
924 		pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
925 		       tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
926 		ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
927 		goto out;
928 	}
929 
930 	inline_dl = get_unaligned_be32(&p[12]);
931 	if (inline_dl != 0) {
932 		pr_err("XCOPY with non zero inline data length\n");
933 		goto out;
934 	}
935 
936 	if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
937 		pr_err("XCOPY parameter truncation: data length %u too small "
938 			"for tdll: %hu sdll: %u inline_dl: %u\n",
939 			se_cmd->data_length, tdll, sdll, inline_dl);
940 		ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
941 		goto out;
942 	}
943 
944 	pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
945 		" tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
946 		tdll, sdll, inline_dl);
947 
948 	/*
949 	 * skip over the target descriptors until segment descriptors
950 	 * have been passed - CSCD ids are needed to determine src and dest.
951 	 */
952 	seg_desc = &p[16] + tdll;
953 
954 	rc = target_xcopy_parse_segment_descriptors(se_cmd, xop, seg_desc,
955 						    sdll, &ret);
956 	if (rc <= 0)
957 		goto out;
958 
959 	pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
960 				rc * XCOPY_SEGMENT_DESC_LEN);
961 
962 	rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
963 	if (rc <= 0)
964 		goto out;
965 
966 	if (xop->src_dev->dev_attrib.block_size !=
967 	    xop->dst_dev->dev_attrib.block_size) {
968 		pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
969 		       " block_size: %u currently unsupported\n",
970 			xop->src_dev->dev_attrib.block_size,
971 			xop->dst_dev->dev_attrib.block_size);
972 		xcopy_pt_undepend_remotedev(xop);
973 		ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
974 		goto out;
975 	}
976 
977 	pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
978 				rc * XCOPY_TARGET_DESC_LEN);
979 	transport_kunmap_data_sg(se_cmd);
980 
981 	INIT_WORK(&xop->xop_work, target_xcopy_do_work);
982 	queue_work(xcopy_wq, &xop->xop_work);
983 	return TCM_NO_SENSE;
984 
985 out:
986 	if (p)
987 		transport_kunmap_data_sg(se_cmd);
988 	kfree(xop);
989 	return ret;
990 }
991 
992 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
993 {
994 	unsigned char *p;
995 
996 	p = transport_kmap_data_sg(se_cmd);
997 	if (!p) {
998 		pr_err("transport_kmap_data_sg failed in"
999 		       " target_rcr_operating_parameters\n");
1000 		return TCM_OUT_OF_RESOURCES;
1001 	}
1002 
1003 	if (se_cmd->data_length < 54) {
1004 		pr_err("Receive Copy Results Op Parameters length"
1005 		       " too small: %u\n", se_cmd->data_length);
1006 		transport_kunmap_data_sg(se_cmd);
1007 		return TCM_INVALID_CDB_FIELD;
1008 	}
1009 	/*
1010 	 * Set SNLID=1 (Supports no List ID)
1011 	 */
1012 	p[4] = 0x1;
1013 	/*
1014 	 * MAXIMUM TARGET DESCRIPTOR COUNT
1015 	 */
1016 	put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
1017 	/*
1018 	 * MAXIMUM SEGMENT DESCRIPTOR COUNT
1019 	 */
1020 	put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
1021 	/*
1022 	 * MAXIMUM DESCRIPTOR LIST LENGTH
1023 	 */
1024 	put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
1025 	/*
1026 	 * MAXIMUM SEGMENT LENGTH
1027 	 */
1028 	put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
1029 	/*
1030 	 * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
1031 	 */
1032 	put_unaligned_be32(0x0, &p[20]);
1033 	/*
1034 	 * HELD DATA LIMIT
1035 	 */
1036 	put_unaligned_be32(0x0, &p[24]);
1037 	/*
1038 	 * MAXIMUM STREAM DEVICE TRANSFER SIZE
1039 	 */
1040 	put_unaligned_be32(0x0, &p[28]);
1041 	/*
1042 	 * TOTAL CONCURRENT COPIES
1043 	 */
1044 	put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
1045 	/*
1046 	 * MAXIMUM CONCURRENT COPIES
1047 	 */
1048 	p[36] = RCR_OP_MAX_CONCURR_COPIES;
1049 	/*
1050 	 * DATA SEGMENT GRANULARITY (log 2)
1051 	 */
1052 	p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
1053 	/*
1054 	 * INLINE DATA GRANULARITY log 2)
1055 	 */
1056 	p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
1057 	/*
1058 	 * HELD DATA GRANULARITY
1059 	 */
1060 	p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
1061 	/*
1062 	 * IMPLEMENTED DESCRIPTOR LIST LENGTH
1063 	 */
1064 	p[43] = 0x2;
1065 	/*
1066 	 * List of implemented descriptor type codes (ordered)
1067 	 */
1068 	p[44] = 0x02; /* Copy Block to Block device */
1069 	p[45] = 0xe4; /* Identification descriptor target descriptor */
1070 
1071 	/*
1072 	 * AVAILABLE DATA (n-3)
1073 	 */
1074 	put_unaligned_be32(42, &p[0]);
1075 
1076 	transport_kunmap_data_sg(se_cmd);
1077 	target_complete_cmd(se_cmd, GOOD);
1078 
1079 	return TCM_NO_SENSE;
1080 }
1081 
1082 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1083 {
1084 	unsigned char *cdb = &se_cmd->t_task_cdb[0];
1085 	int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1086 	sense_reason_t rc = TCM_NO_SENSE;
1087 
1088 	pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1089 		" 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1090 
1091 	if (list_id != 0) {
1092 		pr_err("Receive Copy Results with non zero list identifier"
1093 		       " not supported\n");
1094 		return TCM_INVALID_CDB_FIELD;
1095 	}
1096 
1097 	switch (sa) {
1098 	case RCR_SA_OPERATING_PARAMETERS:
1099 		rc = target_rcr_operating_parameters(se_cmd);
1100 		break;
1101 	case RCR_SA_COPY_STATUS:
1102 	case RCR_SA_RECEIVE_DATA:
1103 	case RCR_SA_FAILED_SEGMENT_DETAILS:
1104 	default:
1105 		pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1106 		return TCM_INVALID_CDB_FIELD;
1107 	}
1108 
1109 	return rc;
1110 }
1111