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 xcopy_op *xop, unsigned char *p)
 299 {
 300         unsigned char *desc = p;
 301         int dc = (desc[1] & 0x02);
 302         unsigned short desc_len;
 303
 304         desc_len = get_unaligned_be16(&desc[2]);
 305         if (desc_len != 0x18) {
 306                 pr_err("XCOPY segment desc 0x02: Illegal desc_len:"
 307                                 " %hu\n", desc_len);
 308                 return -EINVAL;
 309         }
 310
 311         xop->stdi = get_unaligned_be16(&desc[4]);
 312         xop->dtdi = get_unaligned_be16(&desc[6]);
 313
 314         if (xop->stdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX ||
 315             xop->dtdi > XCOPY_CSCD_DESC_ID_LIST_OFF_MAX) {
 316                 pr_err("XCOPY segment desc 0x02: unsupported CSCD ID > 0x%x; stdi: %hu dtdi: %hu\n",
 317                         XCOPY_CSCD_DESC_ID_LIST_OFF_MAX, xop->stdi, xop->dtdi);
 318                 return -EINVAL;
 319         }
 320
 321         pr_debug("XCOPY seg desc 0x02: desc_len: %hu stdi: %hu dtdi: %hu, DC: %d\n",
 322                 desc_len, xop->stdi, xop->dtdi, dc);
 323
 324         xop->nolb = get_unaligned_be16(&desc[10]);
 325         xop->src_lba = get_unaligned_be64(&desc[12]);
 326         xop->dst_lba = get_unaligned_be64(&desc[20]);
 327         pr_debug("XCOPY seg desc 0x02: nolb: %hu src_lba: %llu dst_lba: %llu\n",
 328                 xop->nolb, (unsigned long long)xop->src_lba,
 329                 (unsigned long long)xop->dst_lba);
 330
 331         return 0;
 332 }
 333
 334 static int target_xcopy_parse_segment_descriptors(struct xcopy_op *xop,
 335                                 unsigned char *p, unsigned int sdll,
 336                                 sense_reason_t *sense_ret)
 337 {
 338         unsigned char *desc = p;
 339         unsigned int start = 0;
 340         int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
 341
 342         *sense_ret = TCM_INVALID_PARAMETER_LIST;
 343
 344         if (offset != 0) {
 345                 pr_err("XCOPY segment descriptor list length is not"
 346                         " multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
 347                 *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
 348                 return -EINVAL;
 349         }
 350         if (sdll > RCR_OP_MAX_SG_DESC_COUNT * XCOPY_SEGMENT_DESC_LEN) {
 351                 pr_err("XCOPY supports %u segment descriptor(s), sdll: %u too"
 352                         " large..\n", RCR_OP_MAX_SG_DESC_COUNT, sdll);
 353                 /* spc4r37 6.4.3.5 SEGMENT DESCRIPTOR LIST LENGTH field */
 354                 *sense_ret = TCM_TOO_MANY_SEGMENT_DESCS;
 355                 return -EINVAL;
 356         }
 357
 358         while (start < sdll) {
 359                 /*
 360                  * Check segment descriptor type code for block -> block
 361                  */
 362                 switch (desc[0]) {
 363                 case 0x02:
 364                         rc = target_xcopy_parse_segdesc_02(xop, desc);
 365                         if (rc < 0)
 366                                 goto out;
 367
 368                         ret++;
 369                         start += XCOPY_SEGMENT_DESC_LEN;
 370                         desc += XCOPY_SEGMENT_DESC_LEN;
 371                         break;
 372                 default:
 373                         pr_err("XCOPY unsupported segment descriptor"
 374                                 "type: 0x%02x\n", desc[0]);
 375                         *sense_ret = TCM_UNSUPPORTED_SEGMENT_DESC_TYPE_CODE;
 376                         goto out;
 377                 }
 378         }
 379
 380         return ret;
 381
 382 out:
 383         return -EINVAL;
 384 }
 385
 386 /*
 387  * Start xcopy_pt ops
 388  */
 389
 390 struct xcopy_pt_cmd {
 391         struct se_cmd se_cmd;
 392         struct completion xpt_passthrough_sem;
 393         unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
 394 };
 395
 396 struct se_portal_group xcopy_pt_tpg;
 397 static struct se_session xcopy_pt_sess;
 398 static struct se_node_acl xcopy_pt_nacl;
 399
 400 static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
 401 {
 402         return 0;
 403 }
 404
 405 static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
 406 {
 407         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
 408                 pr_debug("putting dst lun_ref for %p\n", xop->dst_dev);
 409         else
 410                 pr_debug("putting src lun_ref for %p\n", xop->src_dev);
 411
 412         percpu_ref_put(xop->remote_lun_ref);
 413 }
 414
 415 static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
 416 {
 417         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 418                                 struct xcopy_pt_cmd, se_cmd);
 419
 420         /* xpt_cmd is on the stack, nothing to free here */
 421         pr_debug("xpt_cmd done: %p\n", xpt_cmd);
 422 }
 423
 424 static int xcopy_pt_check_stop_free(struct se_cmd *se_cmd)
 425 {
 426         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 427                                 struct xcopy_pt_cmd, se_cmd);
 428
 429         complete(&xpt_cmd->xpt_passthrough_sem);
 430         return 0;
 431 }
 432
 433 static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
 434 {
 435         return 0;
 436 }
 437
 438 static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
 439 {
 440         return 0;
 441 }
 442
 443 static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
 444 {
 445         return 0;
 446 }
 447
 448 static const struct target_core_fabric_ops xcopy_pt_tfo = {
 449         .fabric_name            = "xcopy-pt",
 450         .get_cmd_state          = xcopy_pt_get_cmd_state,
 451         .release_cmd            = xcopy_pt_release_cmd,
 452         .check_stop_free        = xcopy_pt_check_stop_free,
 453         .write_pending          = xcopy_pt_write_pending,
 454         .queue_data_in          = xcopy_pt_queue_data_in,
 455         .queue_status           = xcopy_pt_queue_status,
 456 };
 457
 458 /*
 459  * End xcopy_pt_ops
 460  */
 461
 462 int target_xcopy_setup_pt(void)
 463 {
 464         int ret;
 465
 466         xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
 467         if (!xcopy_wq) {
 468                 pr_err("Unable to allocate xcopy_wq\n");
 469                 return -ENOMEM;
 470         }
 471
 472         memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
 473         INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
 474         INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
 475
 476         xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
 477
 478         memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
 479         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
 480         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
 481         memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
 482         ret = transport_init_session(&xcopy_pt_sess);
 483         if (ret < 0)
 484                 goto destroy_wq;
 485
 486         xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
 487         xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
 488
 489         xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
 490         xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
 491
 492         return 0;
 493
 494 destroy_wq:
 495         destroy_workqueue(xcopy_wq);
 496         xcopy_wq = NULL;
 497         return ret;
 498 }
 499
 500 void target_xcopy_release_pt(void)
 501 {
 502         if (xcopy_wq) {
 503                 destroy_workqueue(xcopy_wq);
 504                 transport_uninit_session(&xcopy_pt_sess);
 505         }
 506 }
 507
 508 /*
 509  * target_xcopy_setup_pt_cmd - set up a pass-through command
 510  * @xpt_cmd:     Data structure to initialize.
 511  * @xop:         Describes the XCOPY operation received from an initiator.
 512  * @se_dev:      Backend device to associate with @xpt_cmd if
 513  *               @remote_port == true.
 514  * @cdb:         SCSI CDB to be copied into @xpt_cmd.
 515  * @remote_port: If false, use the LUN through which the XCOPY command has
 516  *               been received. If true, use @se_dev->xcopy_lun.
 517  *
 518  * Set up a SCSI command (READ or WRITE) that will be used to execute an
 519  * XCOPY command.
 520  */
 521 static int target_xcopy_setup_pt_cmd(
 522         struct xcopy_pt_cmd *xpt_cmd,
 523         struct xcopy_op *xop,
 524         struct se_device *se_dev,
 525         unsigned char *cdb,
 526         bool remote_port)
 527 {
 528         struct se_cmd *cmd = &xpt_cmd->se_cmd;
 529
 530         /*
 531          * Setup LUN+port to honor reservations based upon xop->op_origin for
 532          * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
 533          */
 534         if (remote_port) {
 535                 cmd->se_lun = &se_dev->xcopy_lun;
 536                 cmd->se_dev = se_dev;
 537         } else {
 538                 cmd->se_lun = xop->xop_se_cmd->se_lun;
 539                 cmd->se_dev = xop->xop_se_cmd->se_dev;
 540         }
 541         cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
 542
 543         if (target_cmd_init_cdb(cmd, cdb, GFP_KERNEL))
 544                 return -EINVAL;
 545
 546         cmd->tag = 0;
 547         if (target_cmd_parse_cdb(cmd))
 548                 return -EINVAL;
 549
 550         if (transport_generic_map_mem_to_cmd(cmd, xop->xop_data_sg,
 551                                         xop->xop_data_nents, NULL, 0))
 552                 return -EINVAL;
 553
 554         pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
 555                  " %u\n", cmd->t_data_sg, cmd->t_data_nents);
 556
 557         return 0;
 558 }
 559
 560 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
 561 {
 562         struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
 563         sense_reason_t sense_rc;
 564
 565         sense_rc = transport_generic_new_cmd(se_cmd);
 566         if (sense_rc)
 567                 return -EINVAL;
 568
 569         if (se_cmd->data_direction == DMA_TO_DEVICE)
 570                 target_execute_cmd(se_cmd);
 571
 572         wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
 573
 574         pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
 575                         se_cmd->scsi_status);
 576
 577         return (se_cmd->scsi_status) ? -EINVAL : 0;
 578 }
 579
 580 static int target_xcopy_read_source(
 581         struct se_cmd *ec_cmd,
 582         struct xcopy_op *xop,
 583         struct se_device *src_dev,
 584         sector_t src_lba,
 585         u32 src_sectors)
 586 {
 587         struct xcopy_pt_cmd xpt_cmd;
 588         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 589         u32 length = (src_sectors * src_dev->dev_attrib.block_size);
 590         int rc;
 591         unsigned char cdb[16];
 592         bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
 593
 594         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 595         init_completion(&xpt_cmd.xpt_passthrough_sem);
 596
 597         memset(&cdb[0], 0, 16);
 598         cdb[0] = READ_16;
 599         put_unaligned_be64(src_lba, &cdb[2]);
 600         put_unaligned_be32(src_sectors, &cdb[10]);
 601         pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
 602                 (unsigned long long)src_lba, src_sectors, length);
 603
 604         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 605                           DMA_FROM_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 606
 607         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, src_dev, &cdb[0],
 608                                 remote_port);
 609         if (rc < 0) {
 610                 ec_cmd->scsi_status = se_cmd->scsi_status;
 611                 goto out;
 612         }
 613
 614         pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
 615                 " memory\n", xop->xop_data_sg, xop->xop_data_nents);
 616
 617         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 618         if (rc < 0)
 619                 ec_cmd->scsi_status = se_cmd->scsi_status;
 620 out:
 621         transport_generic_free_cmd(se_cmd, 0);
 622         return rc;
 623 }
 624
 625 static int target_xcopy_write_destination(
 626         struct se_cmd *ec_cmd,
 627         struct xcopy_op *xop,
 628         struct se_device *dst_dev,
 629         sector_t dst_lba,
 630         u32 dst_sectors)
 631 {
 632         struct xcopy_pt_cmd xpt_cmd;
 633         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 634         u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
 635         int rc;
 636         unsigned char cdb[16];
 637         bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
 638
 639         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 640         init_completion(&xpt_cmd.xpt_passthrough_sem);
 641
 642         memset(&cdb[0], 0, 16);
 643         cdb[0] = WRITE_16;
 644         put_unaligned_be64(dst_lba, &cdb[2]);
 645         put_unaligned_be32(dst_sectors, &cdb[10]);
 646         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
 647                 (unsigned long long)dst_lba, dst_sectors, length);
 648
 649         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 650                           DMA_TO_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0);
 651
 652         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, dst_dev, &cdb[0],
 653                                 remote_port);
 654         if (rc < 0) {
 655                 ec_cmd->scsi_status = se_cmd->scsi_status;
 656                 goto out;
 657         }
 658
 659         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 660         if (rc < 0)
 661                 ec_cmd->scsi_status = se_cmd->scsi_status;
 662 out:
 663         transport_generic_free_cmd(se_cmd, 0);
 664         return rc;
 665 }
 666
 667 static void target_xcopy_do_work(struct work_struct *work)
 668 {
 669         struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
 670         struct se_cmd *ec_cmd = xop->xop_se_cmd;
 671         struct se_device *src_dev, *dst_dev;
 672         sector_t src_lba, dst_lba, end_lba;
 673         unsigned int max_sectors;
 674         int rc = 0;
 675         unsigned short nolb, max_nolb, copied_nolb = 0;
 676         sense_reason_t sense_rc;
 677
 678         sense_rc = target_parse_xcopy_cmd(xop);
 679         if (sense_rc != TCM_NO_SENSE)
 680                 goto err_free;
 681
 682         if (WARN_ON_ONCE(!xop->src_dev) || WARN_ON_ONCE(!xop->dst_dev)) {
 683                 sense_rc = TCM_INVALID_PARAMETER_LIST;
 684                 goto err_free;
 685         }
 686
 687         src_dev = xop->src_dev;
 688         dst_dev = xop->dst_dev;
 689         src_lba = xop->src_lba;
 690         dst_lba = xop->dst_lba;
 691         nolb = xop->nolb;
 692         end_lba = src_lba + nolb;
 693         /*
 694          * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
 695          * smallest max_sectors between src_dev + dev_dev, or
 696          */
 697         max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
 698                           dst_dev->dev_attrib.hw_max_sectors);
 699         max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
 700
 701         max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
 702
 703         pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
 704                         nolb, max_nolb, (unsigned long long)end_lba);
 705         pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
 706                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
 707
 708         while (src_lba < end_lba) {
 709                 unsigned short cur_nolb = min(nolb, max_nolb);
 710                 u32 cur_bytes = cur_nolb * src_dev->dev_attrib.block_size;
 711
 712                 if (cur_bytes != xop->xop_data_bytes) {
 713                         /*
 714                          * (Re)allocate a buffer large enough to hold the XCOPY
 715                          * I/O size, which can be reused each read / write loop.
 716                          */
 717                         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 718                         rc = target_alloc_sgl(&xop->xop_data_sg,
 719                                               &xop->xop_data_nents,
 720                                               cur_bytes,
 721                                               false, false);
 722                         if (rc < 0)
 723                                 goto out;
 724                         xop->xop_data_bytes = cur_bytes;
 725                 }
 726
 727                 pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
 728                         " cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
 729
 730                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
 731                 if (rc < 0)
 732                         goto out;
 733
 734                 src_lba += cur_nolb;
 735                 pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
 736                                 (unsigned long long)src_lba);
 737
 738                 pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
 739                         " cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
 740
 741                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
 742                                                 dst_lba, cur_nolb);
 743                 if (rc < 0)
 744                         goto out;
 745
 746                 dst_lba += cur_nolb;
 747                 pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
 748                                 (unsigned long long)dst_lba);
 749
 750                 copied_nolb += cur_nolb;
 751                 nolb -= cur_nolb;
 752         }
 753
 754         xcopy_pt_undepend_remotedev(xop);
 755         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 756         kfree(xop);
 757
 758         pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
 759                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
 760         pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
 761                 copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
 762
 763         pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
 764         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
 765         return;
 766
 767 out:
 768         /*
 769          * The XCOPY command was aborted after some data was transferred.
 770          * Terminate command with CHECK CONDITION status, with the sense key
 771          * set to COPY ABORTED.
 772          */
 773         sense_rc = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
 774         xcopy_pt_undepend_remotedev(xop);
 775         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 776
 777 err_free:
 778         kfree(xop);
 779         pr_warn_ratelimited("target_xcopy_do_work: rc: %d, sense: %u, XCOPY operation failed\n",
 780                            rc, sense_rc);
 781         target_complete_cmd_with_sense(ec_cmd, SAM_STAT_CHECK_CONDITION, sense_rc);
 782 }
 783
 784 /*
 785  * Returns TCM_NO_SENSE upon success or a sense code != TCM_NO_SENSE if parsing
 786  * fails.
 787  */
 788 static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop)
 789 {
 790         struct se_cmd *se_cmd = xop->xop_se_cmd;
 791         unsigned char *p = NULL, *seg_desc;
 792         unsigned int list_id, list_id_usage, sdll, inline_dl;
 793         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
 794         int rc;
 795         unsigned short tdll;
 796
 797         p = transport_kmap_data_sg(se_cmd);
 798         if (!p) {
 799                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
 800                 return TCM_OUT_OF_RESOURCES;
 801         }
 802
 803         list_id = p[0];
 804         list_id_usage = (p[1] & 0x18) >> 3;
 805
 806         /*
 807          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
 808          */
 809         tdll = get_unaligned_be16(&p[2]);
 810         sdll = get_unaligned_be32(&p[8]);
 811         if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
 812                 pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
 813                        tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
 814                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 815                 goto out;
 816         }
 817
 818         inline_dl = get_unaligned_be32(&p[12]);
 819         if (inline_dl != 0) {
 820                 pr_err("XCOPY with non zero inline data length\n");
 821                 goto out;
 822         }
 823
 824         if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
 825                 pr_err("XCOPY parameter truncation: data length %u too small "
 826                         "for tdll: %hu sdll: %u inline_dl: %u\n",
 827                         se_cmd->data_length, tdll, sdll, inline_dl);
 828                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 829                 goto out;
 830         }
 831
 832         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
 833                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
 834                 tdll, sdll, inline_dl);
 835
 836         /*
 837          * skip over the target descriptors until segment descriptors
 838          * have been passed - CSCD ids are needed to determine src and dest.
 839          */
 840         seg_desc = &p[16] + tdll;
 841
 842         rc = target_xcopy_parse_segment_descriptors(xop, seg_desc, sdll, &ret);
 843         if (rc <= 0)
 844                 goto out;
 845
 846         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
 847                                 rc * XCOPY_SEGMENT_DESC_LEN);
 848
 849         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
 850         if (rc <= 0)
 851                 goto out;
 852
 853         if (xop->src_dev->dev_attrib.block_size !=
 854             xop->dst_dev->dev_attrib.block_size) {
 855                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
 856                        " block_size: %u currently unsupported\n",
 857                         xop->src_dev->dev_attrib.block_size,
 858                         xop->dst_dev->dev_attrib.block_size);
 859                 xcopy_pt_undepend_remotedev(xop);
 860                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 861                 goto out;
 862         }
 863
 864         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
 865                                 rc * XCOPY_TARGET_DESC_LEN);
 866         transport_kunmap_data_sg(se_cmd);
 867         return TCM_NO_SENSE;
 868
 869 out:
 870         if (p)
 871                 transport_kunmap_data_sg(se_cmd);
 872         return ret;
 873 }
 874
 875 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
 876 {
 877         struct se_device *dev = se_cmd->se_dev;
 878         struct xcopy_op *xop;
 879         unsigned int sa;
 880
 881         if (!dev->dev_attrib.emulate_3pc) {
 882                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
 883                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 884         }
 885
 886         sa = se_cmd->t_task_cdb[1] & 0x1f;
 887         if (sa != 0x00) {
 888                 pr_err("EXTENDED_COPY(LID4) not supported\n");
 889                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 890         }
 891
 892         if (se_cmd->data_length == 0) {
 893                 target_complete_cmd(se_cmd, SAM_STAT_GOOD);
 894                 return TCM_NO_SENSE;
 895         }
 896         if (se_cmd->data_length < XCOPY_HDR_LEN) {
 897                 pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
 898                                 se_cmd->data_length, XCOPY_HDR_LEN);
 899                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
 900         }
 901
 902         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
 903         if (!xop)
 904                 goto err;
 905         xop->xop_se_cmd = se_cmd;
 906         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
 907         if (WARN_ON_ONCE(!queue_work(xcopy_wq, &xop->xop_work)))
 908                 goto free;
 909         return TCM_NO_SENSE;
 910
 911 free:
 912         kfree(xop);
 913
 914 err:
 915         return TCM_OUT_OF_RESOURCES;
 916 }
 917
 918 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
 919 {
 920         unsigned char *p;
 921
 922         p = transport_kmap_data_sg(se_cmd);
 923         if (!p) {
 924                 pr_err("transport_kmap_data_sg failed in"
 925                        " target_rcr_operating_parameters\n");
 926                 return TCM_OUT_OF_RESOURCES;
 927         }
 928
 929         if (se_cmd->data_length < 54) {
 930                 pr_err("Receive Copy Results Op Parameters length"
 931                        " too small: %u\n", se_cmd->data_length);
 932                 transport_kunmap_data_sg(se_cmd);
 933                 return TCM_INVALID_CDB_FIELD;
 934         }
 935         /*
 936          * Set SNLID=1 (Supports no List ID)
 937          */
 938         p[4] = 0x1;
 939         /*
 940          * MAXIMUM TARGET DESCRIPTOR COUNT
 941          */
 942         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
 943         /*
 944          * MAXIMUM SEGMENT DESCRIPTOR COUNT
 945          */
 946         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
 947         /*
 948          * MAXIMUM DESCRIPTOR LIST LENGTH
 949          */
 950         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
 951         /*
 952          * MAXIMUM SEGMENT LENGTH
 953          */
 954         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
 955         /*
 956          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
 957          */
 958         put_unaligned_be32(0x0, &p[20]);
 959         /*
 960          * HELD DATA LIMIT
 961          */
 962         put_unaligned_be32(0x0, &p[24]);
 963         /*
 964          * MAXIMUM STREAM DEVICE TRANSFER SIZE
 965          */
 966         put_unaligned_be32(0x0, &p[28]);
 967         /*
 968          * TOTAL CONCURRENT COPIES
 969          */
 970         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
 971         /*
 972          * MAXIMUM CONCURRENT COPIES
 973          */
 974         p[36] = RCR_OP_MAX_CONCURR_COPIES;
 975         /*
 976          * DATA SEGMENT GRANULARITY (log 2)
 977          */
 978         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
 979         /*
 980          * INLINE DATA GRANULARITY log 2)
 981          */
 982         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
 983         /*
 984          * HELD DATA GRANULARITY
 985          */
 986         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
 987         /*
 988          * IMPLEMENTED DESCRIPTOR LIST LENGTH
 989          */
 990         p[43] = 0x2;
 991         /*
 992          * List of implemented descriptor type codes (ordered)
 993          */
 994         p[44] = 0x02; /* Copy Block to Block device */
 995         p[45] = 0xe4; /* Identification descriptor target descriptor */
 996
 997         /*
 998          * AVAILABLE DATA (n-3)
 999          */
1000         put_unaligned_be32(42, &p[0]);
1001
1002         transport_kunmap_data_sg(se_cmd);
1003         target_complete_cmd(se_cmd, SAM_STAT_GOOD);
1004
1005         return TCM_NO_SENSE;
1006 }
1007
1008 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1009 {
1010         unsigned char *cdb = &se_cmd->t_task_cdb[0];
1011         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1012         sense_reason_t rc = TCM_NO_SENSE;
1013
1014         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1015                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1016
1017         if (list_id != 0) {
1018                 pr_err("Receive Copy Results with non zero list identifier"
1019                        " not supported\n");
1020                 return TCM_INVALID_CDB_FIELD;
1021         }
1022
1023         switch (sa) {
1024         case RCR_SA_OPERATING_PARAMETERS:
1025                 rc = target_rcr_operating_parameters(se_cmd);
1026                 break;
1027         case RCR_SA_COPY_STATUS:
1028         case RCR_SA_RECEIVE_DATA:
1029         case RCR_SA_FAILED_SEGMENT_DETAILS:
1030         default:
1031                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1032                 return TCM_INVALID_CDB_FIELD;
1033         }
1034
1035         return rc;
1036 }