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 /**
  37  * target_xcopy_locate_se_dev_e4_iter - compare XCOPY NAA device identifiers
  38  *
  39  * @se_dev: device being considered for match
  40  * @dev_wwn: XCOPY requested NAA dev_wwn
  41  * @return: 1 on match, 0 on no-match
  42  */
  43 static int target_xcopy_locate_se_dev_e4_iter(struct se_device *se_dev,
  44                                               const unsigned char *dev_wwn)
  45 {
  46         unsigned char tmp_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN];
  47         int rc;
  48
  49         if (!se_dev->dev_attrib.emulate_3pc) {
  50                 pr_debug("XCOPY: emulate_3pc disabled on se_dev %p\n", se_dev);
  51                 return 0;
  52         }
  53
  54         memset(&tmp_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
  55         spc_gen_naa_6h_vendor_specific(se_dev, &tmp_dev_wwn[0]);
  56
  57         rc = memcmp(&tmp_dev_wwn[0], dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN);
  58         if (rc != 0) {
  59                 pr_debug("XCOPY: skip non-matching: %*ph\n",
  60                          XCOPY_NAA_IEEE_REGEX_LEN, tmp_dev_wwn);
  61                 return 0;
  62         }
  63         pr_debug("XCOPY 0xe4: located se_dev: %p\n", se_dev);
  64
  65         return 1;
  66 }
  67
  68 static int target_xcopy_locate_se_dev_e4(struct se_session *sess,
  69                                         const unsigned char *dev_wwn,
  70                                         struct se_device **_found_dev,
  71                                         struct percpu_ref **_found_lun_ref)
  72 {
  73         struct se_dev_entry *deve;
  74         struct se_node_acl *nacl;
  75         struct se_lun *this_lun = NULL;
  76         struct se_device *found_dev = NULL;
  77
  78         /* cmd with NULL sess indicates no associated $FABRIC_MOD */
  79         if (!sess)
  80                 goto err_out;
  81
  82         pr_debug("XCOPY 0xe4: searching for: %*ph\n",
  83                  XCOPY_NAA_IEEE_REGEX_LEN, dev_wwn);
  84
  85         nacl = sess->se_node_acl;
  86         rcu_read_lock();
  87         hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
  88                 struct se_device *this_dev;
  89                 int rc;
  90
  91                 this_lun = rcu_dereference(deve->se_lun);
  92                 this_dev = rcu_dereference_raw(this_lun->lun_se_dev);
  93
  94                 rc = target_xcopy_locate_se_dev_e4_iter(this_dev, dev_wwn);
  95                 if (rc) {
  96                         if (percpu_ref_tryget_live(&this_lun->lun_ref))
  97                                 found_dev = this_dev;
  98                         break;
  99                 }
 100         }
 101         rcu_read_unlock();
 102         if (found_dev == NULL)
 103                 goto err_out;
 104
 105         pr_debug("lun_ref held for se_dev: %p se_dev->se_dev_group: %p\n",
 106                  found_dev, &found_dev->dev_group);
 107         *_found_dev = found_dev;
 108         *_found_lun_ref = &this_lun->lun_ref;
 109         return 0;
 110 err_out:
 111         pr_debug_ratelimited("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n");
 112         return -EINVAL;
 113 }
 114
 115 static int target_xcopy_parse_tiddesc_e4(struct se_cmd *se_cmd, struct xcopy_op *xop,
 116                                 unsigned char *p, unsigned short cscd_index)
 117 {
 118         unsigned char *desc = p;
 119         unsigned short ript;
 120         u8 desig_len;
 121         /*
 122          * Extract RELATIVE INITIATOR PORT IDENTIFIER
 123          */
 124         ript = get_unaligned_be16(&desc[2]);
 125         pr_debug("XCOPY 0xe4: RELATIVE INITIATOR PORT IDENTIFIER: %hu\n", ript);
 126         /*
 127          * Check for supported code set, association, and designator type
 128          */
 129         if ((desc[4] & 0x0f) != 0x1) {
 130                 pr_err("XCOPY 0xe4: code set of non binary type not supported\n");
 131                 return -EINVAL;
 132         }
 133         if ((desc[5] & 0x30) != 0x00) {
 134                 pr_err("XCOPY 0xe4: association other than LUN not supported\n");
 135                 return -EINVAL;
 136         }
 137         if ((desc[5] & 0x0f) != 0x3) {
 138                 pr_err("XCOPY 0xe4: designator type unsupported: 0x%02x\n",
 139                                 (desc[5] & 0x0f));
 140                 return -EINVAL;
 141         }
 142         /*
 143          * Check for matching 16 byte length for NAA IEEE Registered Extended
 144          * Assigned designator
 145          */
 146         desig_len = desc[7];
 147         if (desig_len != XCOPY_NAA_IEEE_REGEX_LEN) {
 148                 pr_err("XCOPY 0xe4: invalid desig_len: %d\n", (int)desig_len);
 149                 return -EINVAL;
 150         }
 151         pr_debug("XCOPY 0xe4: desig_len: %d\n", (int)desig_len);
 152         /*
 153          * Check for NAA IEEE Registered Extended Assigned header..
 154          */
 155         if ((desc[8] & 0xf0) != 0x60) {
 156                 pr_err("XCOPY 0xe4: Unsupported DESIGNATOR TYPE: 0x%02x\n",
 157                                         (desc[8] & 0xf0));
 158                 return -EINVAL;
 159         }
 160
 161         if (cscd_index != xop->stdi && cscd_index != xop->dtdi) {
 162                 pr_debug("XCOPY 0xe4: ignoring CSCD entry %d - neither src nor "
 163                          "dest\n", cscd_index);
 164                 return 0;
 165         }
 166
 167         if (cscd_index == xop->stdi) {
 168                 memcpy(&xop->src_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
 169                 /*
 170                  * Determine if the source designator matches the local device
 171                  */
 172                 if (!memcmp(&xop->local_dev_wwn[0], &xop->src_tid_wwn[0],
 173                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
 174                         xop->op_origin = XCOL_SOURCE_RECV_OP;
 175                         xop->src_dev = se_cmd->se_dev;
 176                         pr_debug("XCOPY 0xe4: Set xop->src_dev %p from source"
 177                                         " received xop\n", xop->src_dev);
 178                 }
 179         }
 180
 181         if (cscd_index == xop->dtdi) {
 182                 memcpy(&xop->dst_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
 183                 /*
 184                  * Determine if the destination designator matches the local
 185                  * device. If @cscd_index corresponds to both source (stdi) and
 186                  * destination (dtdi), or dtdi comes after stdi, then
 187                  * XCOL_DEST_RECV_OP wins.
 188                  */
 189                 if (!memcmp(&xop->local_dev_wwn[0], &xop->dst_tid_wwn[0],
 190                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
 191                         xop->op_origin = XCOL_DEST_RECV_OP;
 192                         xop->dst_dev = se_cmd->se_dev;
 193                         pr_debug("XCOPY 0xe4: Set xop->dst_dev: %p from destination"
 194                                 " received xop\n", xop->dst_dev);
 195                 }
 196         }
 197
 198         return 0;
 199 }
 200
 201 static int target_xcopy_parse_target_descriptors(struct se_cmd *se_cmd,
 202                                 struct xcopy_op *xop, unsigned char *p,
 203                                 unsigned short tdll, sense_reason_t *sense_ret)
 204 {
 205         struct se_device *local_dev = se_cmd->se_dev;
 206         unsigned char *desc = p;
 207         int offset = tdll % XCOPY_TARGET_DESC_LEN, rc;
 208         unsigned short cscd_index = 0;
 209         unsigned short start = 0;
 210
 211         *sense_ret = TCM_INVALID_PARAMETER_LIST;
 212
 213         if (offset != 0) {
 214                 pr_err("XCOPY target descriptor list length is not"
 215                         " multiple of %d\n", XCOPY_TARGET_DESC_LEN);
 216                 *sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
 217                 return -EINVAL;
 218         }
 219         if (tdll > RCR_OP_MAX_TARGET_DESC_COUNT * XCOPY_TARGET_DESC_LEN) {
 220                 pr_err("XCOPY target descriptor supports a maximum"
 221                         " two src/dest descriptors, tdll: %hu too large..\n", tdll);
 222                 /* spc4r37 6.4.3.4 CSCD DESCRIPTOR LIST LENGTH field */
 223                 *sense_ret = TCM_TOO_MANY_TARGET_DESCS;
 224                 return -EINVAL;
 225         }
 226         /*
 227          * Generate an IEEE Registered Extended designator based upon the
 228          * se_device the XCOPY was received upon..
 229          */
 230         memset(&xop->local_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
 231         spc_gen_naa_6h_vendor_specific(local_dev, &xop->local_dev_wwn[0]);
 232
 233         while (start < tdll) {
 234                 /*
 235                  * Check target descriptor identification with 0xE4 type, and
 236                  * compare the current index with the CSCD descriptor IDs in
 237                  * the segment descriptor. Use VPD 0x83 WWPN matching ..
 238                  */
 239                 switch (desc[0]) {
 240                 case 0xe4:
 241                         rc = target_xcopy_parse_tiddesc_e4(se_cmd, xop,
 242                                                         &desc[0], cscd_index);
 243                         if (rc != 0)
 244                                 goto out;
 245                         start += XCOPY_TARGET_DESC_LEN;
 246                         desc += XCOPY_TARGET_DESC_LEN;
 247                         cscd_index++;
 248                         break;
 249                 default:
 250                         pr_err("XCOPY unsupported descriptor type code:"
 251                                         " 0x%02x\n", desc[0]);
 252                         *sense_ret = TCM_UNSUPPORTED_TARGET_DESC_TYPE_CODE;
 253                         goto out;
 254                 }
 255         }
 256
 257         switch (xop->op_origin) {
 258         case XCOL_SOURCE_RECV_OP:
 259                 rc = target_xcopy_locate_se_dev_e4(se_cmd->se_sess,
 260                                                 xop->dst_tid_wwn,
 261                                                 &xop->dst_dev,
 262                                                 &xop->remote_lun_ref);
 263                 break;
 264         case XCOL_DEST_RECV_OP:
 265                 rc = target_xcopy_locate_se_dev_e4(se_cmd->se_sess,
 266                                                 xop->src_tid_wwn,
 267                                                 &xop->src_dev,
 268                                                 &xop->remote_lun_ref);
 269                 break;
 270         default:
 271                 pr_err("XCOPY CSCD descriptor IDs not found in CSCD list - "
 272                         "stdi: %hu dtdi: %hu\n", xop->stdi, xop->dtdi);
 273                 rc = -EINVAL;
 274                 break;
 275         }
 276         /*
 277          * If a matching IEEE NAA 0x83 descriptor for the requested device
 278          * is not located on this node, return COPY_ABORTED with ASQ/ASQC
 279          * 0x0d/0x02 - COPY_TARGET_DEVICE_NOT_REACHABLE to request the
 280          * initiator to fall back to normal copy method.
 281          */
 282         if (rc < 0) {
 283                 *sense_ret = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
 284                 goto out;
 285         }
 286
 287         pr_debug("XCOPY TGT desc: Source dev: %p NAA IEEE WWN: 0x%16phN\n",
 288                  xop->src_dev, &xop->src_tid_wwn[0]);
 289         pr_debug("XCOPY TGT desc: Dest dev: %p NAA IEEE WWN: 0x%16phN\n",
 290                  xop->dst_dev, &xop->dst_tid_wwn[0]);
 291
 292         return cscd_index;
 293
 294 out:
 295         return -EINVAL;
 296 }
 297
 298 static int target_xcopy_parse_segdesc_02(struct se_cmd *se_cmd, struct xcopy_op *xop,
 299                                         unsigned char *p)
 300 {
 301         unsigned char *desc = p;
 302         int dc = (desc[1] & 0x02);
 303         unsigned short desc_len;
 304
 305         desc_len = get_unaligned_be16(&desc[2]);
 306         if (desc_len != 0x18) {
 307                 pr_err("XCOPY segment desc 0x02: Illegal desc_len:"
 308                                 " %hu\n", desc_len);
 309                 return -EINVAL;
 310         }
 311
 312         xop->stdi = get_unaligned_be16(&desc[4]);
 313         xop->dtdi = get_unaligned_be16(&desc[6]);
 314
 315         if (xop->stdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX ||
 316             xop->dtdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX) {
 317                 pr_err("XCOPY segment desc 0x02: unsupported CSCD ID > 0x%x; stdi: %hu dtdi: %hu\n",
 318                         XCOPY_CSCD_DESC_ID_LIST_OFF_MAX, xop->stdi, xop->dtdi);
 319                 return -EINVAL;
 320         }
 321
 322         pr_debug("XCOPY seg desc 0x02: desc_len: %hu stdi: %hu dtdi: %hu, DC: %d\n",
 323                 desc_len, xop->stdi, xop->dtdi, dc);
 324
 325         xop->nolb = get_unaligned_be16(&desc[10]);
 326         xop->src_lba = get_unaligned_be64(&desc[12]);
 327         xop->dst_lba = get_unaligned_be64(&desc[20]);
 328         pr_debug("XCOPY seg desc 0x02: nolb: %hu src_lba: %llu dst_lba: %llu\n",
 329                 xop->nolb, (unsigned long long)xop->src_lba,
 330                 (unsigned long long)xop->dst_lba);
 331
 332         return 0;
 333 }
 334
 335 static int target_xcopy_parse_segment_descriptors(struct se_cmd *se_cmd,
 336                                 struct xcopy_op *xop, unsigned char *p,
 337                                 unsigned int sdll, sense_reason_t *sense_ret)
 338 {
 339         unsigned char *desc = p;
 340         unsigned int start = 0;
 341         int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
 342
 343         *sense_ret = TCM_INVALID_PARAMETER_LIST;
 344
 345         if (offset != 0) {
 346                 pr_err("XCOPY segment descriptor list length is not"
 347                         " multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
 348                 *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
 349                 return -EINVAL;
 350         }
 351         if (sdll > RCR_OP_MAX_SG_DESC_COUNT * XCOPY_SEGMENT_DESC_LEN) {
 352                 pr_err("XCOPY supports %u segment descriptor(s), sdll: %u too"
 353                         " large..\n", RCR_OP_MAX_SG_DESC_COUNT, sdll);
 354                 /* spc4r37 6.4.3.5 SEGMENT DESCRIPTOR LIST LENGTH field */
 355                 *sense_ret = TCM_TOO_MANY_SEGMENT_DESCS;
 356                 return -EINVAL;
 357         }
 358
 359         while (start < sdll) {
 360                 /*
 361                  * Check segment descriptor type code for block -> block
 362                  */
 363                 switch (desc[0]) {
 364                 case 0x02:
 365                         rc = target_xcopy_parse_segdesc_02(se_cmd, xop, desc);
 366                         if (rc < 0)
 367                                 goto out;
 368
 369                         ret++;
 370                         start += XCOPY_SEGMENT_DESC_LEN;
 371                         desc += XCOPY_SEGMENT_DESC_LEN;
 372                         break;
 373                 default:
 374                         pr_err("XCOPY unsupported segment descriptor"
 375                                 "type: 0x%02x\n", desc[0]);
 376                         *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
 377                         goto out;
 378                 }
 379         }
 380
 381         return ret;
 382
 383 out:
 384         return -EINVAL;
 385 }
 386
 387 /*
 388  * Start xcopy_pt ops
 389  */
 390
 391 struct xcopy_pt_cmd {
 392         struct se_cmd se_cmd;
 393         struct completion xpt_passthrough_sem;
 394         unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
 395 };
 396
 397 struct se_portal_group xcopy_pt_tpg;
 398 static struct se_session xcopy_pt_sess;
 399 static struct se_node_acl xcopy_pt_nacl;
 400
 401 static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
 402 {
 403         return 0;
 404 }
 405
 406 static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
 407 {
 408         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
 409                 pr_debug("putting dst lun_ref for %p\n", xop->dst_dev);
 410         else
 411                 pr_debug("putting src lun_ref for %p\n", xop->src_dev);
 412
 413         percpu_ref_put(xop->remote_lun_ref);
 414 }
 415
 416 static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
 417 {
 418         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 419                                 struct xcopy_pt_cmd, se_cmd);
 420
 421         /* xpt_cmd is on the stack, nothing to free here */
 422         pr_debug("xpt_cmd done: %p\n", xpt_cmd);
 423 }
 424
 425 static int xcopy_pt_check_stop_free(struct se_cmd *se_cmd)
 426 {
 427         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 428                                 struct xcopy_pt_cmd, se_cmd);
 429
 430         complete(&xpt_cmd->xpt_passthrough_sem);
 431         return 0;
 432 }
 433
 434 static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
 435 {
 436         return 0;
 437 }
 438
 439 static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
 440 {
 441         return 0;
 442 }
 443
 444 static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
 445 {
 446         return 0;
 447 }
 448
 449 static const struct target_core_fabric_ops xcopy_pt_tfo = {
 450         .fabric_name            = "xcopy-pt",
 451         .get_cmd_state          = xcopy_pt_get_cmd_state,
 452         .release_cmd            = xcopy_pt_release_cmd,
 453         .check_stop_free        = xcopy_pt_check_stop_free,
 454         .write_pending          = xcopy_pt_write_pending,
 455         .queue_data_in          = xcopy_pt_queue_data_in,
 456         .queue_status           = xcopy_pt_queue_status,
 457 };
 458
 459 /*
 460  * End xcopy_pt_ops
 461  */
 462
 463 int target_xcopy_setup_pt(void)
 464 {
 465         int ret;
 466
 467         xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
 468         if (!xcopy_wq) {
 469                 pr_err("Unable to allocate xcopy_wq\n");
 470                 return -ENOMEM;
 471         }
 472
 473         memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
 474         INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
 475         INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
 476
 477         xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
 478
 479         memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
 480         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
 481         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
 482         memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
 483         ret = transport_init_session(&xcopy_pt_sess);
 484         if (ret < 0)
 485                 goto destroy_wq;
 486
 487         xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
 488         xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
 489
 490         xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
 491         xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
 492
 493         return 0;
 494
 495 destroy_wq:
 496         destroy_workqueue(xcopy_wq);
 497         xcopy_wq = NULL;
 498         return ret;
 499 }
 500
 501 void target_xcopy_release_pt(void)
 502 {
 503         if (xcopy_wq) {
 504                 destroy_workqueue(xcopy_wq);
 505                 transport_uninit_session(&xcopy_pt_sess);
 506         }
 507 }
 508
 509 /*
 510  * target_xcopy_setup_pt_cmd - set up a pass-through command
 511  * @xpt_cmd:     Data structure to initialize.
 512  * @xop:         Describes the XCOPY operation received from an initiator.
 513  * @se_dev:      Backend device to associate with @xpt_cmd if
 514  *               @remote_port == true.
 515  * @cdb:         SCSI CDB to be copied into @xpt_cmd.
 516  * @remote_port: If false, use the LUN through which the XCOPY command has
 517  *               been received. If true, use @se_dev->xcopy_lun.
 518  *
 519  * Set up a SCSI command (READ or WRITE) that will be used to execute an
 520  * XCOPY command.
 521  */
 522 static int target_xcopy_setup_pt_cmd(
 523         struct xcopy_pt_cmd *xpt_cmd,
 524         struct xcopy_op *xop,
 525         struct se_device *se_dev,
 526         unsigned char *cdb,
 527         bool remote_port)
 528 {
 529         struct se_cmd *cmd = &xpt_cmd->se_cmd;
 530
 531         /*
 532          * Setup LUN+port to honor reservations based upon xop->op_origin for
 533          * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
 534          */
 535         if (remote_port) {
 536                 cmd->se_lun = &se_dev->xcopy_lun;
 537                 cmd->se_dev = se_dev;
 538         } else {
 539                 cmd->se_lun = xop->xop_se_cmd->se_lun;
 540                 cmd->se_dev = xop->xop_se_cmd->se_dev;
 541         }
 542         cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
 543
 544         if (target_cmd_init_cdb(cmd, cdb, GFP_KERNEL))
 545                 return -EINVAL;
 546
 547         cmd->tag = 0;
 548         if (target_cmd_parse_cdb(cmd))
 549                 return -EINVAL;
 550
 551         if (transport_generic_map_mem_to_cmd(cmd, xop->xop_data_sg,
 552                                         xop->xop_data_nents, NULL, 0))
 553                 return -EINVAL;
 554
 555         pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
 556                  " %u\n", cmd->t_data_sg, cmd->t_data_nents);
 557
 558         return 0;
 559 }
 560
 561 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
 562 {
 563         struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
 564         sense_reason_t sense_rc;
 565
 566         sense_rc = transport_generic_new_cmd(se_cmd);
 567         if (sense_rc)
 568                 return -EINVAL;
 569
 570         if (se_cmd->data_direction == DMA_TO_DEVICE)
 571                 target_execute_cmd(se_cmd);
 572
 573         wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
 574
 575         pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
 576                         se_cmd->scsi_status);
 577
 578         return (se_cmd->scsi_status) ? -EINVAL : 0;
 579 }
 580
 581 static int target_xcopy_read_source(
 582         struct se_cmd *ec_cmd,
 583         struct xcopy_op *xop,
 584         struct se_device *src_dev,
 585         sector_t src_lba,
 586         u32 src_sectors)
 587 {
 588         struct xcopy_pt_cmd xpt_cmd;
 589         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 590         u32 length = (src_sectors * src_dev->dev_attrib.block_size);
 591         int rc;
 592         unsigned char cdb[16];
 593         bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
 594
 595         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 596         init_completion(&xpt_cmd.xpt_passthrough_sem);
 597
 598         memset(&cdb[0], 0, 16);
 599         cdb[0] = READ_16;
 600         put_unaligned_be64(src_lba, &cdb[2]);
 601         put_unaligned_be32(src_sectors, &cdb[10]);
 602         pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
 603                 (unsigned long long)src_lba, src_sectors, length);
 604
 605         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 606                           DMA_FROM_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 607
 608         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, src_dev, &cdb[0],
 609                                 remote_port);
 610         if (rc < 0) {
 611                 ec_cmd->scsi_status = se_cmd->scsi_status;
 612                 goto out;
 613         }
 614
 615         pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
 616                 " memory\n", xop->xop_data_sg, xop->xop_data_nents);
 617
 618         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 619         if (rc < 0)
 620                 ec_cmd->scsi_status = se_cmd->scsi_status;
 621 out:
 622         transport_generic_free_cmd(se_cmd, 0);
 623         return rc;
 624 }
 625
 626 static int target_xcopy_write_destination(
 627         struct se_cmd *ec_cmd,
 628         struct xcopy_op *xop,
 629         struct se_device *dst_dev,
 630         sector_t dst_lba,
 631         u32 dst_sectors)
 632 {
 633         struct xcopy_pt_cmd xpt_cmd;
 634         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 635         u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
 636         int rc;
 637         unsigned char cdb[16];
 638         bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
 639
 640         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 641         init_completion(&xpt_cmd.xpt_passthrough_sem);
 642
 643         memset(&cdb[0], 0, 16);
 644         cdb[0] = WRITE_16;
 645         put_unaligned_be64(dst_lba, &cdb[2]);
 646         put_unaligned_be32(dst_sectors, &cdb[10]);
 647         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
 648                 (unsigned long long)dst_lba, dst_sectors, length);
 649
 650         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 651                           DMA_TO_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 652
 653         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, dst_dev, &cdb[0],
 654                                 remote_port);
 655         if (rc < 0) {
 656                 ec_cmd->scsi_status = se_cmd->scsi_status;
 657                 goto out;
 658         }
 659
 660         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 661         if (rc < 0)
 662                 ec_cmd->scsi_status = se_cmd->scsi_status;
 663 out:
 664         transport_generic_free_cmd(se_cmd, 0);
 665         return rc;
 666 }
 667
 668 static void target_xcopy_do_work(struct work_struct *work)
 669 {
 670         struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
 671         struct se_cmd *ec_cmd = xop->xop_se_cmd;
 672         struct se_device *src_dev, *dst_dev;
 673         sector_t src_lba, dst_lba, end_lba;
 674         unsigned int max_sectors;
 675         int rc = 0;
 676         unsigned short nolb, max_nolb, copied_nolb = 0;
 677         sense_reason_t sense_rc;
 678
 679         sense_rc = target_parse_xcopy_cmd(xop);
 680         if (sense_rc != TCM_NO_SENSE)
 681                 goto err_free;
 682
 683         if (WARN_ON_ONCE(!xop->src_dev) || WARN_ON_ONCE(!xop->dst_dev)) {
 684                 sense_rc = TCM_INVALID_PARAMETER_LIST;
 685                 goto err_free;
 686         }
 687
 688         src_dev = xop->src_dev;
 689         dst_dev = xop->dst_dev;
 690         src_lba = xop->src_lba;
 691         dst_lba = xop->dst_lba;
 692         nolb = xop->nolb;
 693         end_lba = src_lba + nolb;
 694         /*
 695          * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
 696          * smallest max_sectors between src_dev + dev_dev, or
 697          */
 698         max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
 699                           dst_dev->dev_attrib.hw_max_sectors);
 700         max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
 701
 702         max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
 703
 704         pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
 705                         nolb, max_nolb, (unsigned long long)end_lba);
 706         pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
 707                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
 708
 709         while (src_lba < end_lba) {
 710                 unsigned short cur_nolb = min(nolb, max_nolb);
 711                 u32 cur_bytes = cur_nolb * src_dev->dev_attrib.block_size;
 712
 713                 if (cur_bytes != xop->xop_data_bytes) {
 714                         /*
 715                          * (Re)allocate a buffer large enough to hold the XCOPY
 716                          * I/O size, which can be reused each read / write loop.
 717                          */
 718                         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 719                         rc = target_alloc_sgl(&xop->xop_data_sg,
 720                                               &xop->xop_data_nents,
 721                                               cur_bytes,
 722                                               false, false);
 723                         if (rc < 0)
 724                                 goto out;
 725                         xop->xop_data_bytes = cur_bytes;
 726                 }
 727
 728                 pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
 729                         " cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
 730
 731                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
 732                 if (rc < 0)
 733                         goto out;
 734
 735                 src_lba += cur_nolb;
 736                 pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
 737                                 (unsigned long long)src_lba);
 738
 739                 pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
 740                         " cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
 741
 742                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
 743                                                 dst_lba, cur_nolb);
 744                 if (rc < 0)
 745                         goto out;
 746
 747                 dst_lba += cur_nolb;
 748                 pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
 749                                 (unsigned long long)dst_lba);
 750
 751                 copied_nolb += cur_nolb;
 752                 nolb -= cur_nolb;
 753         }
 754
 755         xcopy_pt_undepend_remotedev(xop);
 756         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 757         kfree(xop);
 758
 759         pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
 760                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
 761         pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
 762                 copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
 763
 764         pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
 765         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
 766         return;
 767
 768 out:
 769         /*
 770          * The XCOPY command was aborted after some data was transferred.
 771          * Terminate command with CHECK CONDITION status, with the sense key
 772          * set to COPY ABORTED.
 773          */
 774         sense_rc = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
 775         xcopy_pt_undepend_remotedev(xop);
 776         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 777
 778 err_free:
 779         kfree(xop);
 780         pr_warn_ratelimited("target_xcopy_do_work: rc: %d, sense: %u, XCOPY operation failed\n",
 781                            rc, sense_rc);
 782         target_complete_cmd_with_sense(ec_cmd, SAM_STAT_CHECK_CONDITION, sense_rc);
 783 }
 784
 785 /*
 786  * Returns TCM_NO_SENSE upon success or a sense code != TCM_NO_SENSE if parsing
 787  * fails.
 788  */
 789 static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop)
 790 {
 791         struct se_cmd *se_cmd = xop->xop_se_cmd;
 792         unsigned char *p = NULL, *seg_desc;
 793         unsigned int list_id, list_id_usage, sdll, inline_dl;
 794         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
 795         int rc;
 796         unsigned short tdll;
 797
 798         p = transport_kmap_data_sg(se_cmd);
 799         if (!p) {
 800                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
 801                 return TCM_OUT_OF_RESOURCES;
 802         }
 803
 804         list_id = p[0];
 805         list_id_usage = (p[1] & 0x18) >> 3;
 806
 807         /*
 808          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
 809          */
 810         tdll = get_unaligned_be16(&p[2]);
 811         sdll = get_unaligned_be32(&p[8]);
 812         if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
 813                 pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
 814                        tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
 815                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 816                 goto out;
 817         }
 818
 819         inline_dl = get_unaligned_be32(&p[12]);
 820         if (inline_dl != 0) {
 821                 pr_err("XCOPY with non zero inline data length\n");
 822                 goto out;
 823         }
 824
 825         if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
 826                 pr_err("XCOPY parameter truncation: data length %u too small "
 827                         "for tdll: %hu sdll: %u inline_dl: %u\n",
 828                         se_cmd->data_length, tdll, sdll, inline_dl);
 829                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 830                 goto out;
 831         }
 832
 833         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
 834                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
 835                 tdll, sdll, inline_dl);
 836
 837         /*
 838          * skip over the target descriptors until segment descriptors
 839          * have been passed - CSCD ids are needed to determine src and dest.
 840          */
 841         seg_desc = &p[16] + tdll;
 842
 843         rc = target_xcopy_parse_segment_descriptors(se_cmd, xop, seg_desc,
 844                                                     sdll, &ret);
 845         if (rc <= 0)
 846                 goto out;
 847
 848         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
 849                                 rc * XCOPY_SEGMENT_DESC_LEN);
 850
 851         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
 852         if (rc <= 0)
 853                 goto out;
 854
 855         if (xop->src_dev->dev_attrib.block_size !=
 856             xop->dst_dev->dev_attrib.block_size) {
 857                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
 858                        " block_size: %u currently unsupported\n",
 859                         xop->src_dev->dev_attrib.block_size,
 860                         xop->dst_dev->dev_attrib.block_size);
 861                 xcopy_pt_undepend_remotedev(xop);
 862                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 863                 goto out;
 864         }
 865
 866         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
 867                                 rc * XCOPY_TARGET_DESC_LEN);
 868         transport_kunmap_data_sg(se_cmd);
 869         return TCM_NO_SENSE;
 870
 871 out:
 872         if (p)
 873                 transport_kunmap_data_sg(se_cmd);
 874         return ret;
 875 }
 876
 877 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
 878 {
 879         struct se_device *dev = se_cmd->se_dev;
 880         struct xcopy_op *xop;
 881         unsigned int sa;
 882
 883         if (!dev->dev_attrib.emulate_3pc) {
 884                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
 885                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 886         }
 887
 888         sa = se_cmd->t_task_cdb[1] & 0x1f;
 889         if (sa != 0x00) {
 890                 pr_err("EXTENDED_COPY(LID4) not supported\n");
 891                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 892         }
 893
 894         if (se_cmd->data_length == 0) {
 895                 target_complete_cmd(se_cmd, SAM_STAT_GOOD);
 896                 return TCM_NO_SENSE;
 897         }
 898         if (se_cmd->data_length < XCOPY_HDR_LEN) {
 899                 pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
 900                                 se_cmd->data_length, XCOPY_HDR_LEN);
 901                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
 902         }
 903
 904         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
 905         if (!xop)
 906                 goto err;
 907         xop->xop_se_cmd = se_cmd;
 908         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
 909         if (WARN_ON_ONCE(!queue_work(xcopy_wq, &xop->xop_work)))
 910                 goto free;
 911         return TCM_NO_SENSE;
 912
 913 free:
 914         kfree(xop);
 915
 916 err:
 917         return TCM_OUT_OF_RESOURCES;
 918 }
 919
 920 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
 921 {
 922         unsigned char *p;
 923
 924         p = transport_kmap_data_sg(se_cmd);
 925         if (!p) {
 926                 pr_err("transport_kmap_data_sg failed in"
 927                        " target_rcr_operating_parameters\n");
 928                 return TCM_OUT_OF_RESOURCES;
 929         }
 930
 931         if (se_cmd->data_length < 54) {
 932                 pr_err("Receive Copy Results Op Parameters length"
 933                        " too small: %u\n", se_cmd->data_length);
 934                 transport_kunmap_data_sg(se_cmd);
 935                 return TCM_INVALID_CDB_FIELD;
 936         }
 937         /*
 938          * Set SNLID=1 (Supports no List ID)
 939          */
 940         p[4] = 0x1;
 941         /*
 942          * MAXIMUM TARGET DESCRIPTOR COUNT
 943          */
 944         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
 945         /*
 946          * MAXIMUM SEGMENT DESCRIPTOR COUNT
 947          */
 948         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
 949         /*
 950          * MAXIMUM DESCRIPTOR LIST LENGTH
 951          */
 952         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
 953         /*
 954          * MAXIMUM SEGMENT LENGTH
 955          */
 956         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
 957         /*
 958          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
 959          */
 960         put_unaligned_be32(0x0, &p[20]);
 961         /*
 962          * HELD DATA LIMIT
 963          */
 964         put_unaligned_be32(0x0, &p[24]);
 965         /*
 966          * MAXIMUM STREAM DEVICE TRANSFER SIZE
 967          */
 968         put_unaligned_be32(0x0, &p[28]);
 969         /*
 970          * TOTAL CONCURRENT COPIES
 971          */
 972         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
 973         /*
 974          * MAXIMUM CONCURRENT COPIES
 975          */
 976         p[36] = RCR_OP_MAX_CONCURR_COPIES;
 977         /*
 978          * DATA SEGMENT GRANULARITY (log 2)
 979          */
 980         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
 981         /*
 982          * INLINE DATA GRANULARITY log 2)
 983          */
 984         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
 985         /*
 986          * HELD DATA GRANULARITY
 987          */
 988         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
 989         /*
 990          * IMPLEMENTED DESCRIPTOR LIST LENGTH
 991          */
 992         p[43] = 0x2;
 993         /*
 994          * List of implemented descriptor type codes (ordered)
 995          */
 996         p[44] = 0x02; /* Copy Block to Block device */
 997         p[45] = 0xe4; /* Identification descriptor target descriptor */
 998
 999         /*
1000          * AVAILABLE DATA (n-3)
1001          */
1002         put_unaligned_be32(42, &p[0]);
1003
1004         transport_kunmap_data_sg(se_cmd);
1005         target_complete_cmd(se_cmd, SAM_STAT_GOOD);
1006
1007         return TCM_NO_SENSE;
1008 }
1009
1010 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1011 {
1012         unsigned char *cdb = &se_cmd->t_task_cdb[0];
1013         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1014         sense_reason_t rc = TCM_NO_SENSE;
1015
1016         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1017                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1018
1019         if (list_id != 0) {
1020                 pr_err("Receive Copy Results with non zero list identifier"
1021                        " not supported\n");
1022                 return TCM_INVALID_CDB_FIELD;
1023         }
1024
1025         switch (sa) {
1026         case RCR_SA_OPERATING_PARAMETERS:
1027                 rc = target_rcr_operating_parameters(se_cmd);
1028                 break;
1029         case RCR_SA_COPY_STATUS:
1030         case RCR_SA_RECEIVE_DATA:
1031         case RCR_SA_FAILED_SEGMENT_DETAILS:
1032         default:
1033                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1034                 return TCM_INVALID_CDB_FIELD;
1035         }
1036
1037         return rc;
1038 }