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