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