treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
[sfrench/cifs-2.6.git] / drivers / target / target_core_xcopy.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * Filename: target_core_xcopy.c
4  *
5  * This file contains support for SPC-4 Extended-Copy offload with generic
6  * TCM backends.
7  *
8  * Copyright (c) 2011-2013 Datera, Inc. All rights reserved.
9  *
10  * Author:
11  * Nicholas A. Bellinger <nab@daterainc.com>
12  *
13  ******************************************************************************/
14
15 #include <linux/slab.h>
16 #include <linux/spinlock.h>
17 #include <linux/list.h>
18 #include <linux/configfs.h>
19 #include <linux/ratelimit.h>
20 #include <scsi/scsi_proto.h>
21 #include <asm/unaligned.h>
22
23 #include <target/target_core_base.h>
24 #include <target/target_core_backend.h>
25 #include <target/target_core_fabric.h>
26
27 #include "target_core_internal.h"
28 #include "target_core_pr.h"
29 #include "target_core_ua.h"
30 #include "target_core_xcopy.h"
31
32 static struct workqueue_struct *xcopy_wq = NULL;
33
34 static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop);
35
36 static int target_xcopy_gen_naa_ieee(struct se_device *dev, unsigned char *buf)
37 {
38         int off = 0;
39
40         buf[off++] = (0x6 << 4);
41         buf[off++] = 0x01;
42         buf[off++] = 0x40;
43         buf[off] = (0x5 << 4);
44
45         spc_parse_naa_6h_vendor_specific(dev, &buf[off]);
46         return 0;
47 }
48
49 struct xcopy_dev_search_info {
50         const unsigned char *dev_wwn;
51         struct se_device *found_dev;
52 };
53
54 static int target_xcopy_locate_se_dev_e4_iter(struct se_device *se_dev,
55                                               void *data)
56 {
57         struct xcopy_dev_search_info *info = data;
58         unsigned char tmp_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN];
59         int rc;
60
61         if (!se_dev->dev_attrib.emulate_3pc)
62                 return 0;
63
64         memset(&tmp_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
65         target_xcopy_gen_naa_ieee(se_dev, &tmp_dev_wwn[0]);
66
67         rc = memcmp(&tmp_dev_wwn[0], info->dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN);
68         if (rc != 0)
69                 return 0;
70
71         info->found_dev = se_dev;
72         pr_debug("XCOPY 0xe4: located se_dev: %p\n", se_dev);
73
74         rc = target_depend_item(&se_dev->dev_group.cg_item);
75         if (rc != 0) {
76                 pr_err("configfs_depend_item attempt failed: %d for se_dev: %p\n",
77                        rc, se_dev);
78                 return rc;
79         }
80
81         pr_debug("Called configfs_depend_item for se_dev: %p se_dev->se_dev_group: %p\n",
82                  se_dev, &se_dev->dev_group);
83         return 1;
84 }
85
86 static int target_xcopy_locate_se_dev_e4(const unsigned char *dev_wwn,
87                                         struct se_device **found_dev)
88 {
89         struct xcopy_dev_search_info info;
90         int ret;
91
92         memset(&info, 0, sizeof(info));
93         info.dev_wwn = dev_wwn;
94
95         ret = target_for_each_device(target_xcopy_locate_se_dev_e4_iter, &info);
96         if (ret == 1) {
97                 *found_dev = info.found_dev;
98                 return 0;
99         } else {
100                 pr_debug_ratelimited("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n");
101                 return -EINVAL;
102         }
103 }
104
105 static int target_xcopy_parse_tiddesc_e4(struct se_cmd *se_cmd, struct xcopy_op *xop,
106                                 unsigned char *p, unsigned short cscd_index)
107 {
108         unsigned char *desc = p;
109         unsigned short ript;
110         u8 desig_len;
111         /*
112          * Extract RELATIVE INITIATOR PORT IDENTIFIER
113          */
114         ript = get_unaligned_be16(&desc[2]);
115         pr_debug("XCOPY 0xe4: RELATIVE INITIATOR PORT IDENTIFIER: %hu\n", ript);
116         /*
117          * Check for supported code set, association, and designator type
118          */
119         if ((desc[4] & 0x0f) != 0x1) {
120                 pr_err("XCOPY 0xe4: code set of non binary type not supported\n");
121                 return -EINVAL;
122         }
123         if ((desc[5] & 0x30) != 0x00) {
124                 pr_err("XCOPY 0xe4: association other than LUN not supported\n");
125                 return -EINVAL;
126         }
127         if ((desc[5] & 0x0f) != 0x3) {
128                 pr_err("XCOPY 0xe4: designator type unsupported: 0x%02x\n",
129                                 (desc[5] & 0x0f));
130                 return -EINVAL;
131         }
132         /*
133          * Check for matching 16 byte length for NAA IEEE Registered Extended
134          * Assigned designator
135          */
136         desig_len = desc[7];
137         if (desig_len != 16) {
138                 pr_err("XCOPY 0xe4: invalid desig_len: %d\n", (int)desig_len);
139                 return -EINVAL;
140         }
141         pr_debug("XCOPY 0xe4: desig_len: %d\n", (int)desig_len);
142         /*
143          * Check for NAA IEEE Registered Extended Assigned header..
144          */
145         if ((desc[8] & 0xf0) != 0x60) {
146                 pr_err("XCOPY 0xe4: Unsupported DESIGNATOR TYPE: 0x%02x\n",
147                                         (desc[8] & 0xf0));
148                 return -EINVAL;
149         }
150
151         if (cscd_index != xop->stdi && cscd_index != xop->dtdi) {
152                 pr_debug("XCOPY 0xe4: ignoring CSCD entry %d - neither src nor "
153                          "dest\n", cscd_index);
154                 return 0;
155         }
156
157         if (cscd_index == xop->stdi) {
158                 memcpy(&xop->src_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
159                 /*
160                  * Determine if the source designator matches the local device
161                  */
162                 if (!memcmp(&xop->local_dev_wwn[0], &xop->src_tid_wwn[0],
163                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
164                         xop->op_origin = XCOL_SOURCE_RECV_OP;
165                         xop->src_dev = se_cmd->se_dev;
166                         pr_debug("XCOPY 0xe4: Set xop->src_dev %p from source"
167                                         " received xop\n", xop->src_dev);
168                 }
169         }
170
171         if (cscd_index == xop->dtdi) {
172                 memcpy(&xop->dst_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
173                 /*
174                  * Determine if the destination designator matches the local
175                  * device. If @cscd_index corresponds to both source (stdi) and
176                  * destination (dtdi), or dtdi comes after stdi, then
177                  * XCOL_DEST_RECV_OP wins.
178                  */
179                 if (!memcmp(&xop->local_dev_wwn[0], &xop->dst_tid_wwn[0],
180                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
181                         xop->op_origin = XCOL_DEST_RECV_OP;
182                         xop->dst_dev = se_cmd->se_dev;
183                         pr_debug("XCOPY 0xe4: Set xop->dst_dev: %p from destination"
184                                 " received xop\n", xop->dst_dev);
185                 }
186         }
187
188         return 0;
189 }
190
191 static int target_xcopy_parse_target_descriptors(struct se_cmd *se_cmd,
192                                 struct xcopy_op *xop, unsigned char *p,
193                                 unsigned short tdll, sense_reason_t *sense_ret)
194 {
195         struct se_device *local_dev = se_cmd->se_dev;
196         unsigned char *desc = p;
197         int offset = tdll % XCOPY_TARGET_DESC_LEN, rc;
198         unsigned short cscd_index = 0;
199         unsigned short start = 0;
200
201         *sense_ret = TCM_INVALID_PARAMETER_LIST;
202
203         if (offset != 0) {
204                 pr_err("XCOPY target descriptor list length is not"
205                         " multiple of %d\n", XCOPY_TARGET_DESC_LEN);
206                 *sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
207                 return -EINVAL;
208         }
209         if (tdll > RCR_OP_MAX_TARGET_DESC_COUNT * XCOPY_TARGET_DESC_LEN) {
210                 pr_err("XCOPY target descriptor supports a maximum"
211                         " two src/dest descriptors, tdll: %hu too large..\n", tdll);
212                 /* spc4r37 6.4.3.4 CSCD DESCRIPTOR LIST LENGTH field */
213                 *sense_ret = TCM_TOO_MANY_TARGET_DESCS;
214                 return -EINVAL;
215         }
216         /*
217          * Generate an IEEE Registered Extended designator based upon the
218          * se_device the XCOPY was received upon..
219          */
220         memset(&xop->local_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
221         target_xcopy_gen_naa_ieee(local_dev, &xop->local_dev_wwn[0]);
222
223         while (start < tdll) {
224                 /*
225                  * Check target descriptor identification with 0xE4 type, and
226                  * compare the current index with the CSCD descriptor IDs in
227                  * the segment descriptor. Use VPD 0x83 WWPN matching ..
228                  */
229                 switch (desc[0]) {
230                 case 0xe4:
231                         rc = target_xcopy_parse_tiddesc_e4(se_cmd, xop,
232                                                         &desc[0], cscd_index);
233                         if (rc != 0)
234                                 goto out;
235                         start += XCOPY_TARGET_DESC_LEN;
236                         desc += XCOPY_TARGET_DESC_LEN;
237                         cscd_index++;
238                         break;
239                 default:
240                         pr_err("XCOPY unsupported descriptor type code:"
241                                         " 0x%02x\n", desc[0]);
242                         *sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
243                         goto out;
244                 }
245         }
246
247         switch (xop->op_origin) {
248         case XCOL_SOURCE_RECV_OP:
249                 rc = target_xcopy_locate_se_dev_e4(xop->dst_tid_wwn,
250                                                 &xop->dst_dev);
251                 break;
252         case XCOL_DEST_RECV_OP:
253                 rc = target_xcopy_locate_se_dev_e4(xop->src_tid_wwn,
254                                                 &xop->src_dev);
255                 break;
256         default:
257                 pr_err("XCOPY CSCD descriptor IDs not found in CSCD list - "
258                         "stdi: %hu dtdi: %hu\n", xop->stdi, xop->dtdi);
259                 rc = -EINVAL;
260                 break;
261         }
262         /*
263          * If a matching IEEE NAA 0x83 descriptor for the requested device
264          * is not located on this node, return COPY_ABORTED with ASQ/ASQC
265          * 0x0d/0x02 - COPY_TARGET_DEVICE_NOT_REACHABLE to request the
266          * initiator to fall back to normal copy method.
267          */
268         if (rc < 0) {
269                 *sense_ret = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
270                 goto out;
271         }
272
273         pr_debug("XCOPY TGT desc: Source dev: %p NAA IEEE WWN: 0x%16phN\n",
274                  xop->src_dev, &xop->src_tid_wwn[0]);
275         pr_debug("XCOPY TGT desc: Dest dev: %p NAA IEEE WWN: 0x%16phN\n",
276                  xop->dst_dev, &xop->dst_tid_wwn[0]);
277
278         return cscd_index;
279
280 out:
281         return -EINVAL;
282 }
283
284 static int target_xcopy_parse_segdesc_02(struct se_cmd *se_cmd, struct xcopy_op *xop,
285                                         unsigned char *p)
286 {
287         unsigned char *desc = p;
288         int dc = (desc[1] & 0x02);
289         unsigned short desc_len;
290
291         desc_len = get_unaligned_be16(&desc[2]);
292         if (desc_len != 0x18) {
293                 pr_err("XCOPY segment desc 0x02: Illegal desc_len:"
294                                 " %hu\n", desc_len);
295                 return -EINVAL;
296         }
297
298         xop->stdi = get_unaligned_be16(&desc[4]);
299         xop->dtdi = get_unaligned_be16(&desc[6]);
300
301         if (xop->stdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX ||
302             xop->dtdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX) {
303                 pr_err("XCOPY segment desc 0x02: unsupported CSCD ID > 0x%x; stdi: %hu dtdi: %hu\n",
304                         XCOPY_CSCD_DESC_ID_LIST_OFF_MAX, xop->stdi, xop->dtdi);
305                 return -EINVAL;
306         }
307
308         pr_debug("XCOPY seg desc 0x02: desc_len: %hu stdi: %hu dtdi: %hu, DC: %d\n",
309                 desc_len, xop->stdi, xop->dtdi, dc);
310
311         xop->nolb = get_unaligned_be16(&desc[10]);
312         xop->src_lba = get_unaligned_be64(&desc[12]);
313         xop->dst_lba = get_unaligned_be64(&desc[20]);
314         pr_debug("XCOPY seg desc 0x02: nolb: %hu src_lba: %llu dst_lba: %llu\n",
315                 xop->nolb, (unsigned long long)xop->src_lba,
316                 (unsigned long long)xop->dst_lba);
317
318         if (dc != 0) {
319                 xop->dbl = get_unaligned_be24(&desc[29]);
320
321                 pr_debug("XCOPY seg desc 0x02: DC=1 w/ dbl: %u\n", xop->dbl);
322         }
323         return 0;
324 }
325
326 static int target_xcopy_parse_segment_descriptors(struct se_cmd *se_cmd,
327                                 struct xcopy_op *xop, unsigned char *p,
328                                 unsigned int sdll, sense_reason_t *sense_ret)
329 {
330         unsigned char *desc = p;
331         unsigned int start = 0;
332         int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
333
334         *sense_ret = TCM_INVALID_PARAMETER_LIST;
335
336         if (offset != 0) {
337                 pr_err("XCOPY segment descriptor list length is not"
338                         " multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
339                 *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
340                 return -EINVAL;
341         }
342         if (sdll > RCR_OP_MAX_SG_DESC_COUNT * XCOPY_SEGMENT_DESC_LEN) {
343                 pr_err("XCOPY supports %u segment descriptor(s), sdll: %u too"
344                         " large..\n", RCR_OP_MAX_SG_DESC_COUNT, sdll);
345                 /* spc4r37 6.4.3.5 SEGMENT DESCRIPTOR LIST LENGTH field */
346                 *sense_ret = TCM_TOO_MANY_SEGMENT_DESCS;
347                 return -EINVAL;
348         }
349
350         while (start < sdll) {
351                 /*
352                  * Check segment descriptor type code for block -> block
353                  */
354                 switch (desc[0]) {
355                 case 0x02:
356                         rc = target_xcopy_parse_segdesc_02(se_cmd, xop, desc);
357                         if (rc < 0)
358                                 goto out;
359
360                         ret++;
361                         start += XCOPY_SEGMENT_DESC_LEN;
362                         desc += XCOPY_SEGMENT_DESC_LEN;
363                         break;
364                 default:
365                         pr_err("XCOPY unsupported segment descriptor"
366                                 "type: 0x%02x\n", desc[0]);
367                         *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
368                         goto out;
369                 }
370         }
371
372         return ret;
373
374 out:
375         return -EINVAL;
376 }
377
378 /*
379  * Start xcopy_pt ops
380  */
381
382 struct xcopy_pt_cmd {
383         struct se_cmd se_cmd;
384         struct completion xpt_passthrough_sem;
385         unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
386 };
387
388 struct se_portal_group xcopy_pt_tpg;
389 static struct se_session xcopy_pt_sess;
390 static struct se_node_acl xcopy_pt_nacl;
391
392 static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
393 {
394         return 0;
395 }
396
397 static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
398 {
399         struct se_device *remote_dev;
400
401         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
402                 remote_dev = xop->dst_dev;
403         else
404                 remote_dev = xop->src_dev;
405
406         pr_debug("Calling configfs_undepend_item for"
407                   " remote_dev: %p remote_dev->dev_group: %p\n",
408                   remote_dev, &remote_dev->dev_group.cg_item);
409
410         target_undepend_item(&remote_dev->dev_group.cg_item);
411 }
412
413 static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
414 {
415         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
416                                 struct xcopy_pt_cmd, se_cmd);
417
418         kfree(xpt_cmd);
419 }
420
421 static int xcopy_pt_check_stop_free(struct se_cmd *se_cmd)
422 {
423         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
424                                 struct xcopy_pt_cmd, se_cmd);
425
426         complete(&xpt_cmd->xpt_passthrough_sem);
427         return 0;
428 }
429
430 static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
431 {
432         return 0;
433 }
434
435 static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
436 {
437         return 0;
438 }
439
440 static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
441 {
442         return 0;
443 }
444
445 static const struct target_core_fabric_ops xcopy_pt_tfo = {
446         .fabric_name            = "xcopy-pt",
447         .get_cmd_state          = xcopy_pt_get_cmd_state,
448         .release_cmd            = xcopy_pt_release_cmd,
449         .check_stop_free        = xcopy_pt_check_stop_free,
450         .write_pending          = xcopy_pt_write_pending,
451         .queue_data_in          = xcopy_pt_queue_data_in,
452         .queue_status           = xcopy_pt_queue_status,
453 };
454
455 /*
456  * End xcopy_pt_ops
457  */
458
459 int target_xcopy_setup_pt(void)
460 {
461         int ret;
462
463         xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
464         if (!xcopy_wq) {
465                 pr_err("Unable to allocate xcopy_wq\n");
466                 return -ENOMEM;
467         }
468
469         memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
470         INIT_LIST_HEAD(&xcopy_pt_tpg.se_tpg_node);
471         INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
472         INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
473
474         xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
475
476         memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
477         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
478         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
479         memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
480         ret = transport_init_session(&xcopy_pt_sess);
481         if (ret < 0)
482                 return ret;
483
484         xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
485         xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
486
487         xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
488         xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
489
490         return 0;
491 }
492
493 void target_xcopy_release_pt(void)
494 {
495         if (xcopy_wq)
496                 destroy_workqueue(xcopy_wq);
497 }
498
499 /*
500  * target_xcopy_setup_pt_cmd - set up a pass-through command
501  * @xpt_cmd:     Data structure to initialize.
502  * @xop:         Describes the XCOPY operation received from an initiator.
503  * @se_dev:      Backend device to associate with @xpt_cmd if
504  *               @remote_port == true.
505  * @cdb:         SCSI CDB to be copied into @xpt_cmd.
506  * @remote_port: If false, use the LUN through which the XCOPY command has
507  *               been received. If true, use @se_dev->xcopy_lun.
508  * @alloc_mem:   Whether or not to allocate an SGL list.
509  *
510  * Set up a SCSI command (READ or WRITE) that will be used to execute an
511  * XCOPY command.
512  */
513 static int target_xcopy_setup_pt_cmd(
514         struct xcopy_pt_cmd *xpt_cmd,
515         struct xcopy_op *xop,
516         struct se_device *se_dev,
517         unsigned char *cdb,
518         bool remote_port,
519         bool alloc_mem)
520 {
521         struct se_cmd *cmd = &xpt_cmd->se_cmd;
522         sense_reason_t sense_rc;
523         int ret = 0, rc;
524
525         /*
526          * Setup LUN+port to honor reservations based upon xop->op_origin for
527          * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
528          */
529         if (remote_port) {
530                 cmd->se_lun = &se_dev->xcopy_lun;
531                 cmd->se_dev = se_dev;
532         } else {
533                 cmd->se_lun = xop->xop_se_cmd->se_lun;
534                 cmd->se_dev = xop->xop_se_cmd->se_dev;
535         }
536         cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
537
538         cmd->tag = 0;
539         sense_rc = target_setup_cmd_from_cdb(cmd, cdb);
540         if (sense_rc) {
541                 ret = -EINVAL;
542                 goto out;
543         }
544
545         if (alloc_mem) {
546                 rc = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
547                                       cmd->data_length, false, false);
548                 if (rc < 0) {
549                         ret = rc;
550                         goto out;
551                 }
552                 /*
553                  * Set this bit so that transport_free_pages() allows the
554                  * caller to release SGLs + physical memory allocated by
555                  * transport_generic_get_mem()..
556                  */
557                 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
558         } else {
559                 /*
560                  * Here the previously allocated SGLs for the internal READ
561                  * are mapped zero-copy to the internal WRITE.
562                  */
563                 sense_rc = transport_generic_map_mem_to_cmd(cmd,
564                                         xop->xop_data_sg, xop->xop_data_nents,
565                                         NULL, 0);
566                 if (sense_rc) {
567                         ret = -EINVAL;
568                         goto out;
569                 }
570
571                 pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
572                          " %u\n", cmd->t_data_sg, cmd->t_data_nents);
573         }
574
575         return 0;
576
577 out:
578         return ret;
579 }
580
581 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
582 {
583         struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
584         sense_reason_t sense_rc;
585
586         sense_rc = transport_generic_new_cmd(se_cmd);
587         if (sense_rc)
588                 return -EINVAL;
589
590         if (se_cmd->data_direction == DMA_TO_DEVICE)
591                 target_execute_cmd(se_cmd);
592
593         wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
594
595         pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
596                         se_cmd->scsi_status);
597
598         return (se_cmd->scsi_status) ? -EINVAL : 0;
599 }
600
601 static int target_xcopy_read_source(
602         struct se_cmd *ec_cmd,
603         struct xcopy_op *xop,
604         struct se_device *src_dev,
605         sector_t src_lba,
606         u32 src_sectors)
607 {
608         struct xcopy_pt_cmd *xpt_cmd;
609         struct se_cmd *se_cmd;
610         u32 length = (src_sectors * src_dev->dev_attrib.block_size);
611         int rc;
612         unsigned char cdb[16];
613         bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
614
615         xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
616         if (!xpt_cmd) {
617                 pr_err("Unable to allocate xcopy_pt_cmd\n");
618                 return -ENOMEM;
619         }
620         init_completion(&xpt_cmd->xpt_passthrough_sem);
621         se_cmd = &xpt_cmd->se_cmd;
622
623         memset(&cdb[0], 0, 16);
624         cdb[0] = READ_16;
625         put_unaligned_be64(src_lba, &cdb[2]);
626         put_unaligned_be32(src_sectors, &cdb[10]);
627         pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
628                 (unsigned long long)src_lba, src_sectors, length);
629
630         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
631                               DMA_FROM_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
632         xop->src_pt_cmd = xpt_cmd;
633
634         rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, src_dev, &cdb[0],
635                                 remote_port, true);
636         if (rc < 0) {
637                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
638                 transport_generic_free_cmd(se_cmd, 0);
639                 return rc;
640         }
641
642         xop->xop_data_sg = se_cmd->t_data_sg;
643         xop->xop_data_nents = se_cmd->t_data_nents;
644         pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
645                 " memory\n", xop->xop_data_sg, xop->xop_data_nents);
646
647         rc = target_xcopy_issue_pt_cmd(xpt_cmd);
648         if (rc < 0) {
649                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
650                 transport_generic_free_cmd(se_cmd, 0);
651                 return rc;
652         }
653         /*
654          * Clear off the allocated t_data_sg, that has been saved for
655          * zero-copy WRITE submission reuse in struct xcopy_op..
656          */
657         se_cmd->t_data_sg = NULL;
658         se_cmd->t_data_nents = 0;
659
660         return 0;
661 }
662
663 static int target_xcopy_write_destination(
664         struct se_cmd *ec_cmd,
665         struct xcopy_op *xop,
666         struct se_device *dst_dev,
667         sector_t dst_lba,
668         u32 dst_sectors)
669 {
670         struct xcopy_pt_cmd *xpt_cmd;
671         struct se_cmd *se_cmd;
672         u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
673         int rc;
674         unsigned char cdb[16];
675         bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
676
677         xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
678         if (!xpt_cmd) {
679                 pr_err("Unable to allocate xcopy_pt_cmd\n");
680                 return -ENOMEM;
681         }
682         init_completion(&xpt_cmd->xpt_passthrough_sem);
683         se_cmd = &xpt_cmd->se_cmd;
684
685         memset(&cdb[0], 0, 16);
686         cdb[0] = WRITE_16;
687         put_unaligned_be64(dst_lba, &cdb[2]);
688         put_unaligned_be32(dst_sectors, &cdb[10]);
689         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
690                 (unsigned long long)dst_lba, dst_sectors, length);
691
692         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
693                               DMA_TO_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
694         xop->dst_pt_cmd = xpt_cmd;
695
696         rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, dst_dev, &cdb[0],
697                                 remote_port, false);
698         if (rc < 0) {
699                 struct se_cmd *src_cmd = &xop->src_pt_cmd->se_cmd;
700                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
701                 /*
702                  * If the failure happened before the t_mem_list hand-off in
703                  * target_xcopy_setup_pt_cmd(), Reset memory + clear flag so that
704                  * core releases this memory on error during X-COPY WRITE I/O.
705                  */
706                 src_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
707                 src_cmd->t_data_sg = xop->xop_data_sg;
708                 src_cmd->t_data_nents = xop->xop_data_nents;
709
710                 transport_generic_free_cmd(se_cmd, 0);
711                 return rc;
712         }
713
714         rc = target_xcopy_issue_pt_cmd(xpt_cmd);
715         if (rc < 0) {
716                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
717                 se_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
718                 transport_generic_free_cmd(se_cmd, 0);
719                 return rc;
720         }
721
722         return 0;
723 }
724
725 static void target_xcopy_do_work(struct work_struct *work)
726 {
727         struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
728         struct se_cmd *ec_cmd = xop->xop_se_cmd;
729         struct se_device *src_dev, *dst_dev;
730         sector_t src_lba, dst_lba, end_lba;
731         unsigned int max_sectors;
732         int rc = 0;
733         unsigned short nolb, cur_nolb, max_nolb, copied_nolb = 0;
734
735         if (target_parse_xcopy_cmd(xop) != TCM_NO_SENSE)
736                 goto err_free;
737
738         if (WARN_ON_ONCE(!xop->src_dev) || WARN_ON_ONCE(!xop->dst_dev))
739                 goto err_free;
740
741         src_dev = xop->src_dev;
742         dst_dev = xop->dst_dev;
743         src_lba = xop->src_lba;
744         dst_lba = xop->dst_lba;
745         nolb = xop->nolb;
746         end_lba = src_lba + nolb;
747         /*
748          * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
749          * smallest max_sectors between src_dev + dev_dev, or
750          */
751         max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
752                           dst_dev->dev_attrib.hw_max_sectors);
753         max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
754
755         max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
756
757         pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
758                         nolb, max_nolb, (unsigned long long)end_lba);
759         pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
760                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
761
762         while (src_lba < end_lba) {
763                 cur_nolb = min(nolb, max_nolb);
764
765                 pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
766                         " cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
767
768                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
769                 if (rc < 0)
770                         goto out;
771
772                 src_lba += cur_nolb;
773                 pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
774                                 (unsigned long long)src_lba);
775
776                 pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
777                         " cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
778
779                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
780                                                 dst_lba, cur_nolb);
781                 if (rc < 0) {
782                         transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
783                         goto out;
784                 }
785
786                 dst_lba += cur_nolb;
787                 pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
788                                 (unsigned long long)dst_lba);
789
790                 copied_nolb += cur_nolb;
791                 nolb -= cur_nolb;
792
793                 transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
794                 xop->dst_pt_cmd->se_cmd.se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
795
796                 transport_generic_free_cmd(&xop->dst_pt_cmd->se_cmd, 0);
797         }
798
799         xcopy_pt_undepend_remotedev(xop);
800         kfree(xop);
801
802         pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
803                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
804         pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
805                 copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
806
807         pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
808         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
809         return;
810
811 out:
812         xcopy_pt_undepend_remotedev(xop);
813
814 err_free:
815         kfree(xop);
816         /*
817          * Don't override an error scsi status if it has already been set
818          */
819         if (ec_cmd->scsi_status == SAM_STAT_GOOD) {
820                 pr_warn_ratelimited("target_xcopy_do_work: rc: %d, Setting X-COPY"
821                         " CHECK_CONDITION -> sending response\n", rc);
822                 ec_cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
823         }
824         target_complete_cmd(ec_cmd, ec_cmd->scsi_status);
825 }
826
827 /*
828  * Returns TCM_NO_SENSE upon success or a sense code != TCM_NO_SENSE if parsing
829  * fails.
830  */
831 static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop)
832 {
833         struct se_cmd *se_cmd = xop->xop_se_cmd;
834         unsigned char *p = NULL, *seg_desc;
835         unsigned int list_id, list_id_usage, sdll, inline_dl;
836         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
837         int rc;
838         unsigned short tdll;
839
840         p = transport_kmap_data_sg(se_cmd);
841         if (!p) {
842                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
843                 return TCM_OUT_OF_RESOURCES;
844         }
845
846         list_id = p[0];
847         list_id_usage = (p[1] & 0x18) >> 3;
848
849         /*
850          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
851          */
852         tdll = get_unaligned_be16(&p[2]);
853         sdll = get_unaligned_be32(&p[8]);
854         if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
855                 pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
856                        tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
857                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
858                 goto out;
859         }
860
861         inline_dl = get_unaligned_be32(&p[12]);
862         if (inline_dl != 0) {
863                 pr_err("XCOPY with non zero inline data length\n");
864                 goto out;
865         }
866
867         if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
868                 pr_err("XCOPY parameter truncation: data length %u too small "
869                         "for tdll: %hu sdll: %u inline_dl: %u\n",
870                         se_cmd->data_length, tdll, sdll, inline_dl);
871                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
872                 goto out;
873         }
874
875         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
876                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
877                 tdll, sdll, inline_dl);
878
879         /*
880          * skip over the target descriptors until segment descriptors
881          * have been passed - CSCD ids are needed to determine src and dest.
882          */
883         seg_desc = &p[16] + tdll;
884
885         rc = target_xcopy_parse_segment_descriptors(se_cmd, xop, seg_desc,
886                                                     sdll, &ret);
887         if (rc <= 0)
888                 goto out;
889
890         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
891                                 rc * XCOPY_SEGMENT_DESC_LEN);
892
893         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
894         if (rc <= 0)
895                 goto out;
896
897         if (xop->src_dev->dev_attrib.block_size !=
898             xop->dst_dev->dev_attrib.block_size) {
899                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
900                        " block_size: %u currently unsupported\n",
901                         xop->src_dev->dev_attrib.block_size,
902                         xop->dst_dev->dev_attrib.block_size);
903                 xcopy_pt_undepend_remotedev(xop);
904                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
905                 goto out;
906         }
907
908         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
909                                 rc * XCOPY_TARGET_DESC_LEN);
910         transport_kunmap_data_sg(se_cmd);
911         return TCM_NO_SENSE;
912
913 out:
914         if (p)
915                 transport_kunmap_data_sg(se_cmd);
916         return ret;
917 }
918
919 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
920 {
921         struct se_device *dev = se_cmd->se_dev;
922         struct xcopy_op *xop;
923         unsigned int sa;
924
925         if (!dev->dev_attrib.emulate_3pc) {
926                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
927                 return TCM_UNSUPPORTED_SCSI_OPCODE;
928         }
929
930         sa = se_cmd->t_task_cdb[1] & 0x1f;
931         if (sa != 0x00) {
932                 pr_err("EXTENDED_COPY(LID4) not supported\n");
933                 return TCM_UNSUPPORTED_SCSI_OPCODE;
934         }
935
936         if (se_cmd->data_length == 0) {
937                 target_complete_cmd(se_cmd, SAM_STAT_GOOD);
938                 return TCM_NO_SENSE;
939         }
940         if (se_cmd->data_length < XCOPY_HDR_LEN) {
941                 pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
942                                 se_cmd->data_length, XCOPY_HDR_LEN);
943                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
944         }
945
946         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
947         if (!xop)
948                 goto err;
949         xop->xop_se_cmd = se_cmd;
950         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
951         if (WARN_ON_ONCE(!queue_work(xcopy_wq, &xop->xop_work)))
952                 goto free;
953         return TCM_NO_SENSE;
954
955 free:
956         kfree(xop);
957
958 err:
959         return TCM_OUT_OF_RESOURCES;
960 }
961
962 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
963 {
964         unsigned char *p;
965
966         p = transport_kmap_data_sg(se_cmd);
967         if (!p) {
968                 pr_err("transport_kmap_data_sg failed in"
969                        " target_rcr_operating_parameters\n");
970                 return TCM_OUT_OF_RESOURCES;
971         }
972
973         if (se_cmd->data_length < 54) {
974                 pr_err("Receive Copy Results Op Parameters length"
975                        " too small: %u\n", se_cmd->data_length);
976                 transport_kunmap_data_sg(se_cmd);
977                 return TCM_INVALID_CDB_FIELD;
978         }
979         /*
980          * Set SNLID=1 (Supports no List ID)
981          */
982         p[4] = 0x1;
983         /*
984          * MAXIMUM TARGET DESCRIPTOR COUNT
985          */
986         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
987         /*
988          * MAXIMUM SEGMENT DESCRIPTOR COUNT
989          */
990         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
991         /*
992          * MAXIMUM DESCRIPTOR LIST LENGTH
993          */
994         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
995         /*
996          * MAXIMUM SEGMENT LENGTH
997          */
998         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
999         /*
1000          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
1001          */
1002         put_unaligned_be32(0x0, &p[20]);
1003         /*
1004          * HELD DATA LIMIT
1005          */
1006         put_unaligned_be32(0x0, &p[24]);
1007         /*
1008          * MAXIMUM STREAM DEVICE TRANSFER SIZE
1009          */
1010         put_unaligned_be32(0x0, &p[28]);
1011         /*
1012          * TOTAL CONCURRENT COPIES
1013          */
1014         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
1015         /*
1016          * MAXIMUM CONCURRENT COPIES
1017          */
1018         p[36] = RCR_OP_MAX_CONCURR_COPIES;
1019         /*
1020          * DATA SEGMENT GRANULARITY (log 2)
1021          */
1022         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
1023         /*
1024          * INLINE DATA GRANULARITY log 2)
1025          */
1026         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
1027         /*
1028          * HELD DATA GRANULARITY
1029          */
1030         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
1031         /*
1032          * IMPLEMENTED DESCRIPTOR LIST LENGTH
1033          */
1034         p[43] = 0x2;
1035         /*
1036          * List of implemented descriptor type codes (ordered)
1037          */
1038         p[44] = 0x02; /* Copy Block to Block device */
1039         p[45] = 0xe4; /* Identification descriptor target descriptor */
1040
1041         /*
1042          * AVAILABLE DATA (n-3)
1043          */
1044         put_unaligned_be32(42, &p[0]);
1045
1046         transport_kunmap_data_sg(se_cmd);
1047         target_complete_cmd(se_cmd, GOOD);
1048
1049         return TCM_NO_SENSE;
1050 }
1051
1052 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1053 {
1054         unsigned char *cdb = &se_cmd->t_task_cdb[0];
1055         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1056         sense_reason_t rc = TCM_NO_SENSE;
1057
1058         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1059                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1060
1061         if (list_id != 0) {
1062                 pr_err("Receive Copy Results with non zero list identifier"
1063                        " not supported\n");
1064                 return TCM_INVALID_CDB_FIELD;
1065         }
1066
1067         switch (sa) {
1068         case RCR_SA_OPERATING_PARAMETERS:
1069                 rc = target_rcr_operating_parameters(se_cmd);
1070                 break;
1071         case RCR_SA_COPY_STATUS:
1072         case RCR_SA_RECEIVE_DATA:
1073         case RCR_SA_FAILED_SEGMENT_DETAILS:
1074         default:
1075                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1076                 return TCM_INVALID_CDB_FIELD;
1077         }
1078
1079         return rc;
1080 }