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