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 <[email protected]>
  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 != XCOPY_NAA_IEEE_REGEX_LEN) {
 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         return 0;
 319 }
 320
 321 static int target_xcopy_parse_segment_descriptors(struct se_cmd *se_cmd,
 322                                 struct xcopy_op *xop, unsigned char *p,
 323                                 unsigned int sdll, sense_reason_t *sense_ret)
 324 {
 325         unsigned char *desc = p;
 326         unsigned int start = 0;
 327         int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
 328
 329         *sense_ret = TCM_INVALID_PARAMETER_LIST;
 330
 331         if (offset != 0) {
 332                 pr_err("XCOPY segment descriptor list length is not"
 333                         " multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
 334                 *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
 335                 return -EINVAL;
 336         }
 337         if (sdll > RCR_OP_MAX_SG_DESC_COUNT * XCOPY_SEGMENT_DESC_LEN) {
 338                 pr_err("XCOPY supports %u segment descriptor(s), sdll: %u too"
 339                         " large..\n", RCR_OP_MAX_SG_DESC_COUNT, sdll);
 340                 /* spc4r37 6.4.3.5 SEGMENT DESCRIPTOR LIST LENGTH field */
 341                 *sense_ret = TCM_TOO_MANY_SEGMENT_DESCS;
 342                 return -EINVAL;
 343         }
 344
 345         while (start < sdll) {
 346                 /*
 347                  * Check segment descriptor type code for block -> block
 348                  */
 349                 switch (desc[0]) {
 350                 case 0x02:
 351                         rc = target_xcopy_parse_segdesc_02(se_cmd, xop, desc);
 352                         if (rc < 0)
 353                                 goto out;
 354
 355                         ret++;
 356                         start += XCOPY_SEGMENT_DESC_LEN;
 357                         desc += XCOPY_SEGMENT_DESC_LEN;
 358                         break;
 359                 default:
 360                         pr_err("XCOPY unsupported segment descriptor"
 361                                 "type: 0x%02x\n", desc[0]);
 362                         *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
 363                         goto out;
 364                 }
 365         }
 366
 367         return ret;
 368
 369 out:
 370         return -EINVAL;
 371 }
 372
 373 /*
 374  * Start xcopy_pt ops
 375  */
 376
 377 struct xcopy_pt_cmd {
 378         struct se_cmd se_cmd;
 379         struct completion xpt_passthrough_sem;
 380         unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
 381 };
 382
 383 struct se_portal_group xcopy_pt_tpg;
 384 static struct se_session xcopy_pt_sess;
 385 static struct se_node_acl xcopy_pt_nacl;
 386
 387 static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
 388 {
 389         return 0;
 390 }
 391
 392 static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
 393 {
 394         struct se_device *remote_dev;
 395
 396         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
 397                 remote_dev = xop->dst_dev;
 398         else
 399                 remote_dev = xop->src_dev;
 400
 401         pr_debug("Calling configfs_undepend_item for"
 402                   " remote_dev: %p remote_dev->dev_group: %p\n",
 403                   remote_dev, &remote_dev->dev_group.cg_item);
 404
 405         target_undepend_item(&remote_dev->dev_group.cg_item);
 406 }
 407
 408 static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
 409 {
 410         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 411                                 struct xcopy_pt_cmd, se_cmd);
 412
 413         /* xpt_cmd is on the stack, nothing to free here */
 414         pr_debug("xpt_cmd done: %p\n", xpt_cmd);
 415 }
 416
 417 static int xcopy_pt_check_stop_free(struct se_cmd *se_cmd)
 418 {
 419         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 420                                 struct xcopy_pt_cmd, se_cmd);
 421
 422         complete(&xpt_cmd->xpt_passthrough_sem);
 423         return 0;
 424 }
 425
 426 static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
 427 {
 428         return 0;
 429 }
 430
 431 static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
 432 {
 433         return 0;
 434 }
 435
 436 static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
 437 {
 438         return 0;
 439 }
 440
 441 static const struct target_core_fabric_ops xcopy_pt_tfo = {
 442         .fabric_name            = "xcopy-pt",
 443         .get_cmd_state          = xcopy_pt_get_cmd_state,
 444         .release_cmd            = xcopy_pt_release_cmd,
 445         .check_stop_free        = xcopy_pt_check_stop_free,
 446         .write_pending          = xcopy_pt_write_pending,
 447         .queue_data_in          = xcopy_pt_queue_data_in,
 448         .queue_status           = xcopy_pt_queue_status,
 449 };
 450
 451 /*
 452  * End xcopy_pt_ops
 453  */
 454
 455 int target_xcopy_setup_pt(void)
 456 {
 457         int ret;
 458
 459         xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
 460         if (!xcopy_wq) {
 461                 pr_err("Unable to allocate xcopy_wq\n");
 462                 return -ENOMEM;
 463         }
 464
 465         memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
 466         INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
 467         INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
 468
 469         xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
 470
 471         memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
 472         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
 473         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
 474         memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
 475         ret = transport_init_session(&xcopy_pt_sess);
 476         if (ret < 0)
 477                 return ret;
 478
 479         xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
 480         xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
 481
 482         xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
 483         xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
 484
 485         return 0;
 486 }
 487
 488 void target_xcopy_release_pt(void)
 489 {
 490         if (xcopy_wq)
 491                 destroy_workqueue(xcopy_wq);
 492 }
 493
 494 /*
 495  * target_xcopy_setup_pt_cmd - set up a pass-through command
 496  * @xpt_cmd:     Data structure to initialize.
 497  * @xop:         Describes the XCOPY operation received from an initiator.
 498  * @se_dev:      Backend device to associate with @xpt_cmd if
 499  *               @remote_port == true.
 500  * @cdb:         SCSI CDB to be copied into @xpt_cmd.
 501  * @remote_port: If false, use the LUN through which the XCOPY command has
 502  *               been received. If true, use @se_dev->xcopy_lun.
 503  *
 504  * Set up a SCSI command (READ or WRITE) that will be used to execute an
 505  * XCOPY command.
 506  */
 507 static int target_xcopy_setup_pt_cmd(
 508         struct xcopy_pt_cmd *xpt_cmd,
 509         struct xcopy_op *xop,
 510         struct se_device *se_dev,
 511         unsigned char *cdb,
 512         bool remote_port)
 513 {
 514         struct se_cmd *cmd = &xpt_cmd->se_cmd;
 515
 516         /*
 517          * Setup LUN+port to honor reservations based upon xop->op_origin for
 518          * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
 519          */
 520         if (remote_port) {
 521                 cmd->se_lun = &se_dev->xcopy_lun;
 522                 cmd->se_dev = se_dev;
 523         } else {
 524                 cmd->se_lun = xop->xop_se_cmd->se_lun;
 525                 cmd->se_dev = xop->xop_se_cmd->se_dev;
 526         }
 527         cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
 528
 529         if (target_cmd_init_cdb(cmd, cdb))
 530                 return -EINVAL;
 531
 532         cmd->tag = 0;
 533         if (target_cmd_parse_cdb(cmd))
 534                 return -EINVAL;
 535
 536         if (transport_generic_map_mem_to_cmd(cmd, xop->xop_data_sg,
 537                                         xop->xop_data_nents, NULL, 0))
 538                 return -EINVAL;
 539
 540         pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
 541                  " %u\n", cmd->t_data_sg, cmd->t_data_nents);
 542
 543         return 0;
 544 }
 545
 546 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
 547 {
 548         struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
 549         sense_reason_t sense_rc;
 550
 551         sense_rc = transport_generic_new_cmd(se_cmd);
 552         if (sense_rc)
 553                 return -EINVAL;
 554
 555         if (se_cmd->data_direction == DMA_TO_DEVICE)
 556                 target_execute_cmd(se_cmd);
 557
 558         wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
 559
 560         pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
 561                         se_cmd->scsi_status);
 562
 563         return (se_cmd->scsi_status) ? -EINVAL : 0;
 564 }
 565
 566 static int target_xcopy_read_source(
 567         struct se_cmd *ec_cmd,
 568         struct xcopy_op *xop,
 569         struct se_device *src_dev,
 570         sector_t src_lba,
 571         u32 src_sectors)
 572 {
 573         struct xcopy_pt_cmd xpt_cmd;
 574         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 575         u32 length = (src_sectors * src_dev->dev_attrib.block_size);
 576         int rc;
 577         unsigned char cdb[16];
 578         bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
 579
 580         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 581         init_completion(&xpt_cmd.xpt_passthrough_sem);
 582
 583         memset(&cdb[0], 0, 16);
 584         cdb[0] = READ_16;
 585         put_unaligned_be64(src_lba, &cdb[2]);
 586         put_unaligned_be32(src_sectors, &cdb[10]);
 587         pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
 588                 (unsigned long long)src_lba, src_sectors, length);
 589
 590         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 591                               DMA_FROM_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 592
 593         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, src_dev, &cdb[0],
 594                                 remote_port);
 595         if (rc < 0) {
 596                 ec_cmd->scsi_status = se_cmd->scsi_status;
 597                 goto out;
 598         }
 599
 600         pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
 601                 " memory\n", xop->xop_data_sg, xop->xop_data_nents);
 602
 603         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 604         if (rc < 0)
 605                 ec_cmd->scsi_status = se_cmd->scsi_status;
 606 out:
 607         transport_generic_free_cmd(se_cmd, 0);
 608         return rc;
 609 }
 610
 611 static int target_xcopy_write_destination(
 612         struct se_cmd *ec_cmd,
 613         struct xcopy_op *xop,
 614         struct se_device *dst_dev,
 615         sector_t dst_lba,
 616         u32 dst_sectors)
 617 {
 618         struct xcopy_pt_cmd xpt_cmd;
 619         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 620         u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
 621         int rc;
 622         unsigned char cdb[16];
 623         bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
 624
 625         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 626         init_completion(&xpt_cmd.xpt_passthrough_sem);
 627
 628         memset(&cdb[0], 0, 16);
 629         cdb[0] = WRITE_16;
 630         put_unaligned_be64(dst_lba, &cdb[2]);
 631         put_unaligned_be32(dst_sectors, &cdb[10]);
 632         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
 633                 (unsigned long long)dst_lba, dst_sectors, length);
 634
 635         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 636                               DMA_TO_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 637
 638         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, dst_dev, &cdb[0],
 639                                 remote_port);
 640         if (rc < 0) {
 641                 ec_cmd->scsi_status = se_cmd->scsi_status;
 642                 goto out;
 643         }
 644
 645         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 646         if (rc < 0)
 647                 ec_cmd->scsi_status = se_cmd->scsi_status;
 648 out:
 649         transport_generic_free_cmd(se_cmd, 0);
 650         return rc;
 651 }
 652
 653 static void target_xcopy_do_work(struct work_struct *work)
 654 {
 655         struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
 656         struct se_cmd *ec_cmd = xop->xop_se_cmd;
 657         struct se_device *src_dev, *dst_dev;
 658         sector_t src_lba, dst_lba, end_lba;
 659         unsigned int max_sectors;
 660         int rc = 0;
 661         unsigned short nolb, max_nolb, copied_nolb = 0;
 662
 663         if (target_parse_xcopy_cmd(xop) != TCM_NO_SENSE)
 664                 goto err_free;
 665
 666         if (WARN_ON_ONCE(!xop->src_dev) || WARN_ON_ONCE(!xop->dst_dev))
 667                 goto err_free;
 668
 669         src_dev = xop->src_dev;
 670         dst_dev = xop->dst_dev;
 671         src_lba = xop->src_lba;
 672         dst_lba = xop->dst_lba;
 673         nolb = xop->nolb;
 674         end_lba = src_lba + nolb;
 675         /*
 676          * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
 677          * smallest max_sectors between src_dev + dev_dev, or
 678          */
 679         max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
 680                           dst_dev->dev_attrib.hw_max_sectors);
 681         max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
 682
 683         max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
 684
 685         pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
 686                         nolb, max_nolb, (unsigned long long)end_lba);
 687         pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
 688                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
 689
 690         while (src_lba < end_lba) {
 691                 unsigned short cur_nolb = min(nolb, max_nolb);
 692                 u32 cur_bytes = cur_nolb * src_dev->dev_attrib.block_size;
 693
 694                 if (cur_bytes != xop->xop_data_bytes) {
 695                         /*
 696                          * (Re)allocate a buffer large enough to hold the XCOPY
 697                          * I/O size, which can be reused each read / write loop.
 698                          */
 699                         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 700                         rc = target_alloc_sgl(&xop->xop_data_sg,
 701                                               &xop->xop_data_nents,
 702                                               cur_bytes,
 703                                               false, false);
 704                         if (rc < 0)
 705                                 goto out;
 706                         xop->xop_data_bytes = cur_bytes;
 707                 }
 708
 709                 pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
 710                         " cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
 711
 712                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
 713                 if (rc < 0)
 714                         goto out;
 715
 716                 src_lba += cur_nolb;
 717                 pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
 718                                 (unsigned long long)src_lba);
 719
 720                 pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
 721                         " cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
 722
 723                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
 724                                                 dst_lba, cur_nolb);
 725                 if (rc < 0)
 726                         goto out;
 727
 728                 dst_lba += cur_nolb;
 729                 pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
 730                                 (unsigned long long)dst_lba);
 731
 732                 copied_nolb += cur_nolb;
 733                 nolb -= cur_nolb;
 734         }
 735
 736         xcopy_pt_undepend_remotedev(xop);
 737         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 738         kfree(xop);
 739
 740         pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
 741                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
 742         pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
 743                 copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
 744
 745         pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
 746         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
 747         return;
 748
 749 out:
 750         xcopy_pt_undepend_remotedev(xop);
 751         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 752
 753 err_free:
 754         kfree(xop);
 755         /*
 756          * Don't override an error scsi status if it has already been set
 757          */
 758         if (ec_cmd->scsi_status == SAM_STAT_GOOD) {
 759                 pr_warn_ratelimited("target_xcopy_do_work: rc: %d, Setting X-COPY"
 760                         " CHECK_CONDITION -> sending response\n", rc);
 761                 ec_cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
 762         }
 763         target_complete_cmd(ec_cmd, ec_cmd->scsi_status);
 764 }
 765
 766 /*
 767  * Returns TCM_NO_SENSE upon success or a sense code != TCM_NO_SENSE if parsing
 768  * fails.
 769  */
 770 static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop)
 771 {
 772         struct se_cmd *se_cmd = xop->xop_se_cmd;
 773         unsigned char *p = NULL, *seg_desc;
 774         unsigned int list_id, list_id_usage, sdll, inline_dl;
 775         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
 776         int rc;
 777         unsigned short tdll;
 778
 779         p = transport_kmap_data_sg(se_cmd);
 780         if (!p) {
 781                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
 782                 return TCM_OUT_OF_RESOURCES;
 783         }
 784
 785         list_id = p[0];
 786         list_id_usage = (p[1] & 0x18) >> 3;
 787
 788         /*
 789          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
 790          */
 791         tdll = get_unaligned_be16(&p[2]);
 792         sdll = get_unaligned_be32(&p[8]);
 793         if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
 794                 pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
 795                        tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
 796                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 797                 goto out;
 798         }
 799
 800         inline_dl = get_unaligned_be32(&p[12]);
 801         if (inline_dl != 0) {
 802                 pr_err("XCOPY with non zero inline data length\n");
 803                 goto out;
 804         }
 805
 806         if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
 807                 pr_err("XCOPY parameter truncation: data length %u too small "
 808                         "for tdll: %hu sdll: %u inline_dl: %u\n",
 809                         se_cmd->data_length, tdll, sdll, inline_dl);
 810                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 811                 goto out;
 812         }
 813
 814         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
 815                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
 816                 tdll, sdll, inline_dl);
 817
 818         /*
 819          * skip over the target descriptors until segment descriptors
 820          * have been passed - CSCD ids are needed to determine src and dest.
 821          */
 822         seg_desc = &p[16] + tdll;
 823
 824         rc = target_xcopy_parse_segment_descriptors(se_cmd, xop, seg_desc,
 825                                                     sdll, &ret);
 826         if (rc <= 0)
 827                 goto out;
 828
 829         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
 830                                 rc * XCOPY_SEGMENT_DESC_LEN);
 831
 832         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
 833         if (rc <= 0)
 834                 goto out;
 835
 836         if (xop->src_dev->dev_attrib.block_size !=
 837             xop->dst_dev->dev_attrib.block_size) {
 838                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
 839                        " block_size: %u currently unsupported\n",
 840                         xop->src_dev->dev_attrib.block_size,
 841                         xop->dst_dev->dev_attrib.block_size);
 842                 xcopy_pt_undepend_remotedev(xop);
 843                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 844                 goto out;
 845         }
 846
 847         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
 848                                 rc * XCOPY_TARGET_DESC_LEN);
 849         transport_kunmap_data_sg(se_cmd);
 850         return TCM_NO_SENSE;
 851
 852 out:
 853         if (p)
 854                 transport_kunmap_data_sg(se_cmd);
 855         return ret;
 856 }
 857
 858 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
 859 {
 860         struct se_device *dev = se_cmd->se_dev;
 861         struct xcopy_op *xop;
 862         unsigned int sa;
 863
 864         if (!dev->dev_attrib.emulate_3pc) {
 865                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
 866                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 867         }
 868
 869         sa = se_cmd->t_task_cdb[1] & 0x1f;
 870         if (sa != 0x00) {
 871                 pr_err("EXTENDED_COPY(LID4) not supported\n");
 872                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 873         }
 874
 875         if (se_cmd->data_length == 0) {
 876                 target_complete_cmd(se_cmd, SAM_STAT_GOOD);
 877                 return TCM_NO_SENSE;
 878         }
 879         if (se_cmd->data_length < XCOPY_HDR_LEN) {
 880                 pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
 881                                 se_cmd->data_length, XCOPY_HDR_LEN);
 882                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
 883         }
 884
 885         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
 886         if (!xop)
 887                 goto err;
 888         xop->xop_se_cmd = se_cmd;
 889         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
 890         if (WARN_ON_ONCE(!queue_work(xcopy_wq, &xop->xop_work)))
 891                 goto free;
 892         return TCM_NO_SENSE;
 893
 894 free:
 895         kfree(xop);
 896
 897 err:
 898         return TCM_OUT_OF_RESOURCES;
 899 }
 900
 901 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
 902 {
 903         unsigned char *p;
 904
 905         p = transport_kmap_data_sg(se_cmd);
 906         if (!p) {
 907                 pr_err("transport_kmap_data_sg failed in"
 908                        " target_rcr_operating_parameters\n");
 909                 return TCM_OUT_OF_RESOURCES;
 910         }
 911
 912         if (se_cmd->data_length < 54) {
 913                 pr_err("Receive Copy Results Op Parameters length"
 914                        " too small: %u\n", se_cmd->data_length);
 915                 transport_kunmap_data_sg(se_cmd);
 916                 return TCM_INVALID_CDB_FIELD;
 917         }
 918         /*
 919          * Set SNLID=1 (Supports no List ID)
 920          */
 921         p[4] = 0x1;
 922         /*
 923          * MAXIMUM TARGET DESCRIPTOR COUNT
 924          */
 925         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
 926         /*
 927          * MAXIMUM SEGMENT DESCRIPTOR COUNT
 928          */
 929         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
 930         /*
 931          * MAXIMUM DESCRIPTOR LIST LENGTH
 932          */
 933         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
 934         /*
 935          * MAXIMUM SEGMENT LENGTH
 936          */
 937         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
 938         /*
 939          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
 940          */
 941         put_unaligned_be32(0x0, &p[20]);
 942         /*
 943          * HELD DATA LIMIT
 944          */
 945         put_unaligned_be32(0x0, &p[24]);
 946         /*
 947          * MAXIMUM STREAM DEVICE TRANSFER SIZE
 948          */
 949         put_unaligned_be32(0x0, &p[28]);
 950         /*
 951          * TOTAL CONCURRENT COPIES
 952          */
 953         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
 954         /*
 955          * MAXIMUM CONCURRENT COPIES
 956          */
 957         p[36] = RCR_OP_MAX_CONCURR_COPIES;
 958         /*
 959          * DATA SEGMENT GRANULARITY (log 2)
 960          */
 961         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
 962         /*
 963          * INLINE DATA GRANULARITY log 2)
 964          */
 965         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
 966         /*
 967          * HELD DATA GRANULARITY
 968          */
 969         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
 970         /*
 971          * IMPLEMENTED DESCRIPTOR LIST LENGTH
 972          */
 973         p[43] = 0x2;
 974         /*
 975          * List of implemented descriptor type codes (ordered)
 976          */
 977         p[44] = 0x02; /* Copy Block to Block device */
 978         p[45] = 0xe4; /* Identification descriptor target descriptor */
 979
 980         /*
 981          * AVAILABLE DATA (n-3)
 982          */
 983         put_unaligned_be32(42, &p[0]);
 984
 985         transport_kunmap_data_sg(se_cmd);
 986         target_complete_cmd(se_cmd, GOOD);
 987
 988         return TCM_NO_SENSE;
 989 }
 990
 991 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
 992 {
 993         unsigned char *cdb = &se_cmd->t_task_cdb[0];
 994         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
 995         sense_reason_t rc = TCM_NO_SENSE;
 996
 997         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
 998                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
 999
1000         if (list_id != 0) {
1001                 pr_err("Receive Copy Results with non zero list identifier"
1002                        " not supported\n");
1003                 return TCM_INVALID_CDB_FIELD;
1004         }
1005
1006         switch (sa) {
1007         case RCR_SA_OPERATING_PARAMETERS:
1008                 rc = target_rcr_operating_parameters(se_cmd);
1009                 break;
1010         case RCR_SA_COPY_STATUS:
1011         case RCR_SA_RECEIVE_DATA:
1012         case RCR_SA_FAILED_SEGMENT_DETAILS:
1013         default:
1014                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1015                 return TCM_INVALID_CDB_FIELD;
1016         }
1017
1018         return rc;
1019 }