target: move external declarations to a headers
[firefly-linux-kernel-4.4.55.git] / drivers / target / target_core_xcopy.c
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
42 static struct workqueue_struct *xcopy_wq = NULL;
43
44 static 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
57 static 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         struct configfs_subsystem *subsys = target_core_subsystem[0];
62         unsigned char tmp_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN], *dev_wwn;
63         int rc;
64
65         if (src)
66                 dev_wwn = &xop->dst_tid_wwn[0];
67         else
68                 dev_wwn = &xop->src_tid_wwn[0];
69
70         mutex_lock(&g_device_mutex);
71         list_for_each_entry(se_dev, &g_device_list, g_dev_node) {
72
73                 if (!se_dev->dev_attrib.emulate_3pc)
74                         continue;
75
76                 memset(&tmp_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
77                 target_xcopy_gen_naa_ieee(se_dev, &tmp_dev_wwn[0]);
78
79                 rc = memcmp(&tmp_dev_wwn[0], dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN);
80                 if (rc != 0)
81                         continue;
82
83                 if (src) {
84                         xop->dst_dev = se_dev;
85                         pr_debug("XCOPY 0xe4: Setting xop->dst_dev: %p from located"
86                                 " se_dev\n", xop->dst_dev);
87                 } else {
88                         xop->src_dev = se_dev;
89                         pr_debug("XCOPY 0xe4: Setting xop->src_dev: %p from located"
90                                 " se_dev\n", xop->src_dev);
91                 }
92
93                 rc = configfs_depend_item(subsys,
94                                 &se_dev->dev_group.cg_item);
95                 if (rc != 0) {
96                         pr_err("configfs_depend_item attempt failed:"
97                                 " %d for se_dev: %p\n", rc, se_dev);
98                         mutex_unlock(&g_device_mutex);
99                         return rc;
100                 }
101
102                 pr_debug("Called configfs_depend_item for subsys: %p se_dev: %p"
103                         " se_dev->se_dev_group: %p\n", subsys, se_dev,
104                         &se_dev->dev_group);
105
106                 mutex_unlock(&g_device_mutex);
107                 return 0;
108         }
109         mutex_unlock(&g_device_mutex);
110
111         pr_err("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n");
112         return -EINVAL;
113 }
114
115 static int target_xcopy_parse_tiddesc_e4(struct se_cmd *se_cmd, struct xcopy_op *xop,
116                                 unsigned char *p, bool src)
117 {
118         unsigned char *desc = p;
119         unsigned short ript;
120         u8 desig_len;
121         /*
122          * Extract RELATIVE INITIATOR PORT IDENTIFIER
123          */
124         ript = get_unaligned_be16(&desc[2]);
125         pr_debug("XCOPY 0xe4: RELATIVE INITIATOR PORT IDENTIFIER: %hu\n", ript);
126         /*
127          * Check for supported code set, association, and designator type
128          */
129         if ((desc[4] & 0x0f) != 0x1) {
130                 pr_err("XCOPY 0xe4: code set of non binary type not supported\n");
131                 return -EINVAL;
132         }
133         if ((desc[5] & 0x30) != 0x00) {
134                 pr_err("XCOPY 0xe4: association other than LUN not supported\n");
135                 return -EINVAL;
136         }
137         if ((desc[5] & 0x0f) != 0x3) {
138                 pr_err("XCOPY 0xe4: designator type unsupported: 0x%02x\n",
139                                 (desc[5] & 0x0f));
140                 return -EINVAL;
141         }
142         /*
143          * Check for matching 16 byte length for NAA IEEE Registered Extended
144          * Assigned designator
145          */
146         desig_len = desc[7];
147         if (desig_len != 16) {
148                 pr_err("XCOPY 0xe4: invalid desig_len: %d\n", (int)desig_len);
149                 return -EINVAL;
150         }
151         pr_debug("XCOPY 0xe4: desig_len: %d\n", (int)desig_len);
152         /*
153          * Check for NAA IEEE Registered Extended Assigned header..
154          */
155         if ((desc[8] & 0xf0) != 0x60) {
156                 pr_err("XCOPY 0xe4: Unsupported DESIGNATOR TYPE: 0x%02x\n",
157                                         (desc[8] & 0xf0));
158                 return -EINVAL;
159         }
160
161         if (src) {
162                 memcpy(&xop->src_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
163                 /*
164                  * Determine if the source designator matches the local device
165                  */
166                 if (!memcmp(&xop->local_dev_wwn[0], &xop->src_tid_wwn[0],
167                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
168                         xop->op_origin = XCOL_SOURCE_RECV_OP;
169                         xop->src_dev = se_cmd->se_dev;
170                         pr_debug("XCOPY 0xe4: Set xop->src_dev %p from source"
171                                         " received xop\n", xop->src_dev);
172                 }
173         } else {
174                 memcpy(&xop->dst_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
175                 /*
176                  * Determine if the destination designator matches the local device
177                  */
178                 if (!memcmp(&xop->local_dev_wwn[0], &xop->dst_tid_wwn[0],
179                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
180                         xop->op_origin = XCOL_DEST_RECV_OP;
181                         xop->dst_dev = se_cmd->se_dev;
182                         pr_debug("XCOPY 0xe4: Set xop->dst_dev: %p from destination"
183                                 " received xop\n", xop->dst_dev);
184                 }
185         }
186
187         return 0;
188 }
189
190 static int target_xcopy_parse_target_descriptors(struct se_cmd *se_cmd,
191                                 struct xcopy_op *xop, unsigned char *p,
192                                 unsigned short tdll)
193 {
194         struct se_device *local_dev = se_cmd->se_dev;
195         unsigned char *desc = p;
196         int offset = tdll % XCOPY_TARGET_DESC_LEN, rc, ret = 0;
197         unsigned short start = 0;
198         bool src = true;
199
200         if (offset != 0) {
201                 pr_err("XCOPY target descriptor list length is not"
202                         " multiple of %d\n", XCOPY_TARGET_DESC_LEN);
203                 return -EINVAL;
204         }
205         if (tdll > 64) {
206                 pr_err("XCOPY target descriptor supports a maximum"
207                         " two src/dest descriptors, tdll: %hu too large..\n", tdll);
208                 return -EINVAL;
209         }
210         /*
211          * Generate an IEEE Registered Extended designator based upon the
212          * se_device the XCOPY was received upon..
213          */
214         memset(&xop->local_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
215         target_xcopy_gen_naa_ieee(local_dev, &xop->local_dev_wwn[0]);
216
217         while (start < tdll) {
218                 /*
219                  * Check target descriptor identification with 0xE4 type with
220                  * use VPD 0x83 WWPN matching ..
221                  */
222                 switch (desc[0]) {
223                 case 0xe4:
224                         rc = target_xcopy_parse_tiddesc_e4(se_cmd, xop,
225                                                         &desc[0], src);
226                         if (rc != 0)
227                                 goto out;
228                         /*
229                          * Assume target descriptors are in source -> destination order..
230                          */
231                         if (src)
232                                 src = false;
233                         else
234                                 src = true;
235                         start += XCOPY_TARGET_DESC_LEN;
236                         desc += XCOPY_TARGET_DESC_LEN;
237                         ret++;
238                         break;
239                 default:
240                         pr_err("XCOPY unsupported descriptor type code:"
241                                         " 0x%02x\n", desc[0]);
242                         goto out;
243                 }
244         }
245
246         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
247                 rc = target_xcopy_locate_se_dev_e4(se_cmd, xop, true);
248         else
249                 rc = target_xcopy_locate_se_dev_e4(se_cmd, xop, false);
250
251         if (rc < 0)
252                 goto out;
253
254         pr_debug("XCOPY TGT desc: Source dev: %p NAA IEEE WWN: 0x%16phN\n",
255                  xop->src_dev, &xop->src_tid_wwn[0]);
256         pr_debug("XCOPY TGT desc: Dest dev: %p NAA IEEE WWN: 0x%16phN\n",
257                  xop->dst_dev, &xop->dst_tid_wwn[0]);
258
259         return ret;
260
261 out:
262         return -EINVAL;
263 }
264
265 static int target_xcopy_parse_segdesc_02(struct se_cmd *se_cmd, struct xcopy_op *xop,
266                                         unsigned char *p)
267 {
268         unsigned char *desc = p;
269         int dc = (desc[1] & 0x02);
270         unsigned short desc_len;
271
272         desc_len = get_unaligned_be16(&desc[2]);
273         if (desc_len != 0x18) {
274                 pr_err("XCOPY segment desc 0x02: Illegal desc_len:"
275                                 " %hu\n", desc_len);
276                 return -EINVAL;
277         }
278
279         xop->stdi = get_unaligned_be16(&desc[4]);
280         xop->dtdi = get_unaligned_be16(&desc[6]);
281         pr_debug("XCOPY seg desc 0x02: desc_len: %hu stdi: %hu dtdi: %hu, DC: %d\n",
282                 desc_len, xop->stdi, xop->dtdi, dc);
283
284         xop->nolb = get_unaligned_be16(&desc[10]);
285         xop->src_lba = get_unaligned_be64(&desc[12]);
286         xop->dst_lba = get_unaligned_be64(&desc[20]);
287         pr_debug("XCOPY seg desc 0x02: nolb: %hu src_lba: %llu dst_lba: %llu\n",
288                 xop->nolb, (unsigned long long)xop->src_lba,
289                 (unsigned long long)xop->dst_lba);
290
291         if (dc != 0) {
292                 xop->dbl = (desc[29] & 0xff) << 16;
293                 xop->dbl |= (desc[30] & 0xff) << 8;
294                 xop->dbl |= desc[31] & 0xff;
295
296                 pr_debug("XCOPY seg desc 0x02: DC=1 w/ dbl: %u\n", xop->dbl);
297         }
298         return 0;
299 }
300
301 static int target_xcopy_parse_segment_descriptors(struct se_cmd *se_cmd,
302                                 struct xcopy_op *xop, unsigned char *p,
303                                 unsigned int sdll)
304 {
305         unsigned char *desc = p;
306         unsigned int start = 0;
307         int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
308
309         if (offset != 0) {
310                 pr_err("XCOPY segment descriptor list length is not"
311                         " multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
312                 return -EINVAL;
313         }
314
315         while (start < sdll) {
316                 /*
317                  * Check segment descriptor type code for block -> block
318                  */
319                 switch (desc[0]) {
320                 case 0x02:
321                         rc = target_xcopy_parse_segdesc_02(se_cmd, xop, desc);
322                         if (rc < 0)
323                                 goto out;
324
325                         ret++;
326                         start += XCOPY_SEGMENT_DESC_LEN;
327                         desc += XCOPY_SEGMENT_DESC_LEN;
328                         break;
329                 default:
330                         pr_err("XCOPY unsupported segment descriptor"
331                                 "type: 0x%02x\n", desc[0]);
332                         goto out;
333                 }
334         }
335
336         return ret;
337
338 out:
339         return -EINVAL;
340 }
341
342 /*
343  * Start xcopy_pt ops
344  */
345
346 struct xcopy_pt_cmd {
347         bool remote_port;
348         struct se_cmd se_cmd;
349         struct xcopy_op *xcopy_op;
350         struct completion xpt_passthrough_sem;
351         unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
352 };
353
354 static struct se_port xcopy_pt_port;
355 static struct se_portal_group xcopy_pt_tpg;
356 static struct se_session xcopy_pt_sess;
357 static struct se_node_acl xcopy_pt_nacl;
358
359 static char *xcopy_pt_get_fabric_name(void)
360 {
361         return "xcopy-pt";
362 }
363
364 static u32 xcopy_pt_get_tag(struct se_cmd *se_cmd)
365 {
366         return 0;
367 }
368
369 static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
370 {
371         return 0;
372 }
373
374 static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
375 {
376         struct configfs_subsystem *subsys = target_core_subsystem[0];
377         struct se_device *remote_dev;
378
379         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
380                 remote_dev = xop->dst_dev;
381         else
382                 remote_dev = xop->src_dev;
383
384         pr_debug("Calling configfs_undepend_item for subsys: %p"
385                   " remote_dev: %p remote_dev->dev_group: %p\n",
386                   subsys, remote_dev, &remote_dev->dev_group.cg_item);
387
388         configfs_undepend_item(subsys, &remote_dev->dev_group.cg_item);
389 }
390
391 static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
392 {
393         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
394                                 struct xcopy_pt_cmd, se_cmd);
395
396         kfree(xpt_cmd);
397 }
398
399 static int xcopy_pt_check_stop_free(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         complete(&xpt_cmd->xpt_passthrough_sem);
405         return 0;
406 }
407
408 static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
409 {
410         return 0;
411 }
412
413 static int xcopy_pt_write_pending_status(struct se_cmd *se_cmd)
414 {
415         return 0;
416 }
417
418 static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
419 {
420         return 0;
421 }
422
423 static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
424 {
425         return 0;
426 }
427
428 static struct target_core_fabric_ops xcopy_pt_tfo = {
429         .get_fabric_name        = xcopy_pt_get_fabric_name,
430         .get_task_tag           = xcopy_pt_get_tag,
431         .get_cmd_state          = xcopy_pt_get_cmd_state,
432         .release_cmd            = xcopy_pt_release_cmd,
433         .check_stop_free        = xcopy_pt_check_stop_free,
434         .write_pending          = xcopy_pt_write_pending,
435         .write_pending_status   = xcopy_pt_write_pending_status,
436         .queue_data_in          = xcopy_pt_queue_data_in,
437         .queue_status           = xcopy_pt_queue_status,
438 };
439
440 /*
441  * End xcopy_pt_ops
442  */
443
444 int target_xcopy_setup_pt(void)
445 {
446         xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
447         if (!xcopy_wq) {
448                 pr_err("Unable to allocate xcopy_wq\n");
449                 return -ENOMEM;
450         }
451
452         memset(&xcopy_pt_port, 0, sizeof(struct se_port));
453         INIT_LIST_HEAD(&xcopy_pt_port.sep_alua_list);
454         INIT_LIST_HEAD(&xcopy_pt_port.sep_list);
455         mutex_init(&xcopy_pt_port.sep_tg_pt_md_mutex);
456
457         memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
458         INIT_LIST_HEAD(&xcopy_pt_tpg.se_tpg_node);
459         INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
460         INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
461
462         xcopy_pt_port.sep_tpg = &xcopy_pt_tpg;
463         xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
464
465         memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
466         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
467         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
468         memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
469         INIT_LIST_HEAD(&xcopy_pt_sess.sess_list);
470         INIT_LIST_HEAD(&xcopy_pt_sess.sess_acl_list);
471
472         xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
473         xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
474
475         xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
476         xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
477
478         return 0;
479 }
480
481 void target_xcopy_release_pt(void)
482 {
483         if (xcopy_wq)
484                 destroy_workqueue(xcopy_wq);
485 }
486
487 static void target_xcopy_setup_pt_port(
488         struct xcopy_pt_cmd *xpt_cmd,
489         struct xcopy_op *xop,
490         bool remote_port)
491 {
492         struct se_cmd *ec_cmd = xop->xop_se_cmd;
493         struct se_cmd *pt_cmd = &xpt_cmd->se_cmd;
494
495         if (xop->op_origin == XCOL_SOURCE_RECV_OP) {
496                 /*
497                  * Honor destination port reservations for X-COPY PUSH emulation
498                  * when CDB is received on local source port, and READs blocks to
499                  * WRITE on remote destination port.
500                  */
501                 if (remote_port) {
502                         xpt_cmd->remote_port = remote_port;
503                         pt_cmd->se_lun->lun_sep = &xcopy_pt_port;
504                         pr_debug("Setup emulated remote DEST xcopy_pt_port: %p to"
505                                 " cmd->se_lun->lun_sep for X-COPY data PUSH\n",
506                                 pt_cmd->se_lun->lun_sep);
507                 } else {
508                         pt_cmd->se_lun = ec_cmd->se_lun;
509                         pt_cmd->se_dev = ec_cmd->se_dev;
510
511                         pr_debug("Honoring local SRC port from ec_cmd->se_dev:"
512                                 " %p\n", pt_cmd->se_dev);
513                         pt_cmd->se_lun = ec_cmd->se_lun;
514                         pr_debug("Honoring local SRC port from ec_cmd->se_lun: %p\n",
515                                 pt_cmd->se_lun);
516                 }
517         } else {
518                 /*
519                  * Honor source port reservation for X-COPY PULL emulation
520                  * when CDB is received on local desintation port, and READs
521                  * blocks from the remote source port to WRITE on local
522                  * destination port.
523                  */
524                 if (remote_port) {
525                         xpt_cmd->remote_port = remote_port;
526                         pt_cmd->se_lun->lun_sep = &xcopy_pt_port;
527                         pr_debug("Setup emulated remote SRC xcopy_pt_port: %p to"
528                                 " cmd->se_lun->lun_sep for X-COPY data PULL\n",
529                                 pt_cmd->se_lun->lun_sep);
530                 } else {
531                         pt_cmd->se_lun = ec_cmd->se_lun;
532                         pt_cmd->se_dev = ec_cmd->se_dev;
533
534                         pr_debug("Honoring local DST port from ec_cmd->se_dev:"
535                                 " %p\n", pt_cmd->se_dev);
536                         pt_cmd->se_lun = ec_cmd->se_lun;
537                         pr_debug("Honoring local DST port from ec_cmd->se_lun: %p\n",
538                                 pt_cmd->se_lun);
539                 }
540         }
541 }
542
543 static int target_xcopy_init_pt_lun(
544         struct xcopy_pt_cmd *xpt_cmd,
545         struct xcopy_op *xop,
546         struct se_device *se_dev,
547         struct se_cmd *pt_cmd,
548         bool remote_port)
549 {
550         /*
551          * Don't allocate + init an pt_cmd->se_lun if honoring local port for
552          * reservations.  The pt_cmd->se_lun pointer will be setup from within
553          * target_xcopy_setup_pt_port()
554          */
555         if (!remote_port) {
556                 pt_cmd->se_cmd_flags |= SCF_SE_LUN_CMD | SCF_CMD_XCOPY_PASSTHROUGH;
557                 return 0;
558         }
559
560         pt_cmd->se_lun = &se_dev->xcopy_lun;
561         pt_cmd->se_dev = se_dev;
562
563         pr_debug("Setup emulated se_dev: %p from se_dev\n", pt_cmd->se_dev);
564         pt_cmd->se_cmd_flags |= SCF_SE_LUN_CMD | SCF_CMD_XCOPY_PASSTHROUGH;
565
566         pr_debug("Setup emulated se_dev: %p to pt_cmd->se_lun->lun_se_dev\n",
567                 pt_cmd->se_lun->lun_se_dev);
568
569         return 0;
570 }
571
572 static int target_xcopy_setup_pt_cmd(
573         struct xcopy_pt_cmd *xpt_cmd,
574         struct xcopy_op *xop,
575         struct se_device *se_dev,
576         unsigned char *cdb,
577         bool remote_port,
578         bool alloc_mem)
579 {
580         struct se_cmd *cmd = &xpt_cmd->se_cmd;
581         sense_reason_t sense_rc;
582         int ret = 0, rc;
583         /*
584          * Setup LUN+port to honor reservations based upon xop->op_origin for
585          * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
586          */
587         rc = target_xcopy_init_pt_lun(xpt_cmd, xop, se_dev, cmd, remote_port);
588         if (rc < 0) {
589                 ret = rc;
590                 goto out;
591         }
592         xpt_cmd->xcopy_op = xop;
593         target_xcopy_setup_pt_port(xpt_cmd, xop, remote_port);
594
595         sense_rc = target_setup_cmd_from_cdb(cmd, cdb);
596         if (sense_rc) {
597                 ret = -EINVAL;
598                 goto out;
599         }
600
601         if (alloc_mem) {
602                 rc = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
603                                       cmd->data_length, false);
604                 if (rc < 0) {
605                         ret = rc;
606                         goto out;
607                 }
608                 /*
609                  * Set this bit so that transport_free_pages() allows the
610                  * caller to release SGLs + physical memory allocated by
611                  * transport_generic_get_mem()..
612                  */
613                 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
614         } else {
615                 /*
616                  * Here the previously allocated SGLs for the internal READ
617                  * are mapped zero-copy to the internal WRITE.
618                  */
619                 sense_rc = transport_generic_map_mem_to_cmd(cmd,
620                                         xop->xop_data_sg, xop->xop_data_nents,
621                                         NULL, 0);
622                 if (sense_rc) {
623                         ret = -EINVAL;
624                         goto out;
625                 }
626
627                 pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
628                          " %u\n", cmd->t_data_sg, cmd->t_data_nents);
629         }
630
631         return 0;
632
633 out:
634         return ret;
635 }
636
637 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
638 {
639         struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
640         sense_reason_t sense_rc;
641
642         sense_rc = transport_generic_new_cmd(se_cmd);
643         if (sense_rc)
644                 return -EINVAL;
645
646         if (se_cmd->data_direction == DMA_TO_DEVICE)
647                 target_execute_cmd(se_cmd);
648
649         wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
650
651         pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
652                         se_cmd->scsi_status);
653
654         return (se_cmd->scsi_status) ? -EINVAL : 0;
655 }
656
657 static int target_xcopy_read_source(
658         struct se_cmd *ec_cmd,
659         struct xcopy_op *xop,
660         struct se_device *src_dev,
661         sector_t src_lba,
662         u32 src_sectors)
663 {
664         struct xcopy_pt_cmd *xpt_cmd;
665         struct se_cmd *se_cmd;
666         u32 length = (src_sectors * src_dev->dev_attrib.block_size);
667         int rc;
668         unsigned char cdb[16];
669         bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
670
671         xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
672         if (!xpt_cmd) {
673                 pr_err("Unable to allocate xcopy_pt_cmd\n");
674                 return -ENOMEM;
675         }
676         init_completion(&xpt_cmd->xpt_passthrough_sem);
677         se_cmd = &xpt_cmd->se_cmd;
678
679         memset(&cdb[0], 0, 16);
680         cdb[0] = READ_16;
681         put_unaligned_be64(src_lba, &cdb[2]);
682         put_unaligned_be32(src_sectors, &cdb[10]);
683         pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
684                 (unsigned long long)src_lba, src_sectors, length);
685
686         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, NULL, length,
687                               DMA_FROM_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
688         xop->src_pt_cmd = xpt_cmd;
689
690         rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, src_dev, &cdb[0],
691                                 remote_port, true);
692         if (rc < 0) {
693                 transport_generic_free_cmd(se_cmd, 0);
694                 return rc;
695         }
696
697         xop->xop_data_sg = se_cmd->t_data_sg;
698         xop->xop_data_nents = se_cmd->t_data_nents;
699         pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
700                 " memory\n", xop->xop_data_sg, xop->xop_data_nents);
701
702         rc = target_xcopy_issue_pt_cmd(xpt_cmd);
703         if (rc < 0) {
704                 transport_generic_free_cmd(se_cmd, 0);
705                 return rc;
706         }
707         /*
708          * Clear off the allocated t_data_sg, that has been saved for
709          * zero-copy WRITE submission reuse in struct xcopy_op..
710          */
711         se_cmd->t_data_sg = NULL;
712         se_cmd->t_data_nents = 0;
713
714         return 0;
715 }
716
717 static int target_xcopy_write_destination(
718         struct se_cmd *ec_cmd,
719         struct xcopy_op *xop,
720         struct se_device *dst_dev,
721         sector_t dst_lba,
722         u32 dst_sectors)
723 {
724         struct xcopy_pt_cmd *xpt_cmd;
725         struct se_cmd *se_cmd;
726         u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
727         int rc;
728         unsigned char cdb[16];
729         bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
730
731         xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
732         if (!xpt_cmd) {
733                 pr_err("Unable to allocate xcopy_pt_cmd\n");
734                 return -ENOMEM;
735         }
736         init_completion(&xpt_cmd->xpt_passthrough_sem);
737         se_cmd = &xpt_cmd->se_cmd;
738
739         memset(&cdb[0], 0, 16);
740         cdb[0] = WRITE_16;
741         put_unaligned_be64(dst_lba, &cdb[2]);
742         put_unaligned_be32(dst_sectors, &cdb[10]);
743         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
744                 (unsigned long long)dst_lba, dst_sectors, length);
745
746         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, NULL, length,
747                               DMA_TO_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
748         xop->dst_pt_cmd = xpt_cmd;
749
750         rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, dst_dev, &cdb[0],
751                                 remote_port, false);
752         if (rc < 0) {
753                 struct se_cmd *src_cmd = &xop->src_pt_cmd->se_cmd;
754                 /*
755                  * If the failure happened before the t_mem_list hand-off in
756                  * target_xcopy_setup_pt_cmd(), Reset memory + clear flag so that
757                  * core releases this memory on error during X-COPY WRITE I/O.
758                  */
759                 src_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
760                 src_cmd->t_data_sg = xop->xop_data_sg;
761                 src_cmd->t_data_nents = xop->xop_data_nents;
762
763                 transport_generic_free_cmd(se_cmd, 0);
764                 return rc;
765         }
766
767         rc = target_xcopy_issue_pt_cmd(xpt_cmd);
768         if (rc < 0) {
769                 se_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
770                 transport_generic_free_cmd(se_cmd, 0);
771                 return rc;
772         }
773
774         return 0;
775 }
776
777 static void target_xcopy_do_work(struct work_struct *work)
778 {
779         struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
780         struct se_device *src_dev = xop->src_dev, *dst_dev = xop->dst_dev;
781         struct se_cmd *ec_cmd = xop->xop_se_cmd;
782         sector_t src_lba = xop->src_lba, dst_lba = xop->dst_lba, end_lba;
783         unsigned int max_sectors;
784         int rc;
785         unsigned short nolb = xop->nolb, cur_nolb, max_nolb, copied_nolb = 0;
786
787         end_lba = src_lba + nolb;
788         /*
789          * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
790          * smallest max_sectors between src_dev + dev_dev, or
791          */
792         max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
793                           dst_dev->dev_attrib.hw_max_sectors);
794         max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
795
796         max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
797
798         pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
799                         nolb, max_nolb, (unsigned long long)end_lba);
800         pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
801                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
802
803         while (src_lba < end_lba) {
804                 cur_nolb = min(nolb, max_nolb);
805
806                 pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
807                         " cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
808
809                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
810                 if (rc < 0)
811                         goto out;
812
813                 src_lba += cur_nolb;
814                 pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
815                                 (unsigned long long)src_lba);
816
817                 pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
818                         " cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
819
820                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
821                                                 dst_lba, cur_nolb);
822                 if (rc < 0) {
823                         transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
824                         goto out;
825                 }
826
827                 dst_lba += cur_nolb;
828                 pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
829                                 (unsigned long long)dst_lba);
830
831                 copied_nolb += cur_nolb;
832                 nolb -= cur_nolb;
833
834                 transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
835                 xop->dst_pt_cmd->se_cmd.se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
836
837                 transport_generic_free_cmd(&xop->dst_pt_cmd->se_cmd, 0);
838         }
839
840         xcopy_pt_undepend_remotedev(xop);
841         kfree(xop);
842
843         pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
844                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
845         pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
846                 copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
847
848         pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
849         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
850         return;
851
852 out:
853         xcopy_pt_undepend_remotedev(xop);
854         kfree(xop);
855
856         pr_warn("target_xcopy_do_work: Setting X-COPY CHECK_CONDITION -> sending response\n");
857         ec_cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
858         target_complete_cmd(ec_cmd, SAM_STAT_CHECK_CONDITION);
859 }
860
861 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
862 {
863         struct se_device *dev = se_cmd->se_dev;
864         struct xcopy_op *xop = NULL;
865         unsigned char *p = NULL, *seg_desc;
866         unsigned int list_id, list_id_usage, sdll, inline_dl, sa;
867         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
868         int rc;
869         unsigned short tdll;
870
871         if (!dev->dev_attrib.emulate_3pc) {
872                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
873                 return TCM_UNSUPPORTED_SCSI_OPCODE;
874         }
875
876         sa = se_cmd->t_task_cdb[1] & 0x1f;
877         if (sa != 0x00) {
878                 pr_err("EXTENDED_COPY(LID4) not supported\n");
879                 return TCM_UNSUPPORTED_SCSI_OPCODE;
880         }
881
882         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
883         if (!xop) {
884                 pr_err("Unable to allocate xcopy_op\n");
885                 return TCM_OUT_OF_RESOURCES;
886         }
887         xop->xop_se_cmd = se_cmd;
888
889         p = transport_kmap_data_sg(se_cmd);
890         if (!p) {
891                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
892                 kfree(xop);
893                 return TCM_OUT_OF_RESOURCES;
894         }
895
896         list_id = p[0];
897         list_id_usage = (p[1] & 0x18) >> 3;
898
899         /*
900          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
901          */
902         tdll = get_unaligned_be16(&p[2]);
903         sdll = get_unaligned_be32(&p[8]);
904
905         inline_dl = get_unaligned_be32(&p[12]);
906         if (inline_dl != 0) {
907                 pr_err("XCOPY with non zero inline data length\n");
908                 goto out;
909         }
910
911         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
912                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
913                 tdll, sdll, inline_dl);
914
915         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll);
916         if (rc <= 0)
917                 goto out;
918
919         if (xop->src_dev->dev_attrib.block_size !=
920             xop->dst_dev->dev_attrib.block_size) {
921                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
922                        " block_size: %u currently unsupported\n",
923                         xop->src_dev->dev_attrib.block_size,
924                         xop->dst_dev->dev_attrib.block_size);
925                 xcopy_pt_undepend_remotedev(xop);
926                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
927                 goto out;
928         }
929
930         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
931                                 rc * XCOPY_TARGET_DESC_LEN);
932         seg_desc = &p[16];
933         seg_desc += (rc * XCOPY_TARGET_DESC_LEN);
934
935         rc = target_xcopy_parse_segment_descriptors(se_cmd, xop, seg_desc, sdll);
936         if (rc <= 0) {
937                 xcopy_pt_undepend_remotedev(xop);
938                 goto out;
939         }
940         transport_kunmap_data_sg(se_cmd);
941
942         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
943                                 rc * XCOPY_SEGMENT_DESC_LEN);
944         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
945         queue_work(xcopy_wq, &xop->xop_work);
946         return TCM_NO_SENSE;
947
948 out:
949         if (p)
950                 transport_kunmap_data_sg(se_cmd);
951         kfree(xop);
952         return ret;
953 }
954
955 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
956 {
957         unsigned char *p;
958
959         p = transport_kmap_data_sg(se_cmd);
960         if (!p) {
961                 pr_err("transport_kmap_data_sg failed in"
962                        " target_rcr_operating_parameters\n");
963                 return TCM_OUT_OF_RESOURCES;
964         }
965
966         if (se_cmd->data_length < 54) {
967                 pr_err("Receive Copy Results Op Parameters length"
968                        " too small: %u\n", se_cmd->data_length);
969                 transport_kunmap_data_sg(se_cmd);
970                 return TCM_INVALID_CDB_FIELD;
971         }
972         /*
973          * Set SNLID=1 (Supports no List ID)
974          */
975         p[4] = 0x1;
976         /*
977          * MAXIMUM TARGET DESCRIPTOR COUNT
978          */
979         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
980         /*
981          * MAXIMUM SEGMENT DESCRIPTOR COUNT
982          */
983         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
984         /*
985          * MAXIMUM DESCRIPTOR LIST LENGTH
986          */
987         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
988         /*
989          * MAXIMUM SEGMENT LENGTH
990          */
991         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
992         /*
993          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
994          */
995         put_unaligned_be32(0x0, &p[20]);
996         /*
997          * HELD DATA LIMIT
998          */
999         put_unaligned_be32(0x0, &p[24]);
1000         /*
1001          * MAXIMUM STREAM DEVICE TRANSFER SIZE
1002          */
1003         put_unaligned_be32(0x0, &p[28]);
1004         /*
1005          * TOTAL CONCURRENT COPIES
1006          */
1007         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
1008         /*
1009          * MAXIMUM CONCURRENT COPIES
1010          */
1011         p[36] = RCR_OP_MAX_CONCURR_COPIES;
1012         /*
1013          * DATA SEGMENT GRANULARITY (log 2)
1014          */
1015         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
1016         /*
1017          * INLINE DATA GRANULARITY log 2)
1018          */
1019         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
1020         /*
1021          * HELD DATA GRANULARITY
1022          */
1023         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
1024         /*
1025          * IMPLEMENTED DESCRIPTOR LIST LENGTH
1026          */
1027         p[43] = 0x2;
1028         /*
1029          * List of implemented descriptor type codes (ordered)
1030          */
1031         p[44] = 0x02; /* Copy Block to Block device */
1032         p[45] = 0xe4; /* Identification descriptor target descriptor */
1033
1034         /*
1035          * AVAILABLE DATA (n-3)
1036          */
1037         put_unaligned_be32(42, &p[0]);
1038
1039         transport_kunmap_data_sg(se_cmd);
1040         target_complete_cmd(se_cmd, GOOD);
1041
1042         return TCM_NO_SENSE;
1043 }
1044
1045 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1046 {
1047         unsigned char *cdb = &se_cmd->t_task_cdb[0];
1048         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1049         sense_reason_t rc = TCM_NO_SENSE;
1050
1051         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1052                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1053
1054         if (list_id != 0) {
1055                 pr_err("Receive Copy Results with non zero list identifier"
1056                        " not supported\n");
1057                 return TCM_INVALID_CDB_FIELD;
1058         }
1059
1060         switch (sa) {
1061         case RCR_SA_OPERATING_PARAMETERS:
1062                 rc = target_rcr_operating_parameters(se_cmd);
1063                 break;
1064         case RCR_SA_COPY_STATUS:
1065         case RCR_SA_RECEIVE_DATA:
1066         case RCR_SA_FAILED_SEGMENT_DETAILS:
1067         default:
1068                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1069                 return TCM_INVALID_CDB_FIELD;
1070         }
1071
1072         return rc;
1073 }