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 }