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 = 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         xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
 465         if (!xcopy_wq) {
 466                 pr_err("Unable to allocate xcopy_wq\n");
 467                 return -ENOMEM;
 468         }
 469
 470         memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
 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         transport_init_session(&xcopy_pt_sess);
 481
 482         xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
 483         xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
 484
 485         xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
 486         xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
 487
 488         return 0;
 489 }
 490
 491 void target_xcopy_release_pt(void)
 492 {
 493         if (xcopy_wq)
 494                 destroy_workqueue(xcopy_wq);
 495 }
 496
 497 /*
 498  * target_xcopy_setup_pt_cmd - set up a pass-through command
 499  * @xpt_cmd:     Data structure to initialize.
 500  * @xop:         Describes the XCOPY operation received from an initiator.
 501  * @se_dev:      Backend device to associate with @xpt_cmd if
 502  *               @remote_port == true.
 503  * @cdb:         SCSI CDB to be copied into @xpt_cmd.
 504  * @remote_port: If false, use the LUN through which the XCOPY command has
 505  *               been received. If true, use @se_dev->xcopy_lun.
 506  *
 507  * Set up a SCSI command (READ or WRITE) that will be used to execute an
 508  * XCOPY command.
 509  */
 510 static int target_xcopy_setup_pt_cmd(
 511         struct xcopy_pt_cmd *xpt_cmd,
 512         struct xcopy_op *xop,
 513         struct se_device *se_dev,
 514         unsigned char *cdb,
 515         bool remote_port)
 516 {
 517         struct se_cmd *cmd = &xpt_cmd->se_cmd;
 518
 519         /*
 520          * Setup LUN+port to honor reservations based upon xop->op_origin for
 521          * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
 522          */
 523         if (remote_port) {
 524                 cmd->se_lun = &se_dev->xcopy_lun;
 525                 cmd->se_dev = se_dev;
 526         } else {
 527                 cmd->se_lun = xop->xop_se_cmd->se_lun;
 528                 cmd->se_dev = xop->xop_se_cmd->se_dev;
 529         }
 530         cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
 531
 532         if (target_cmd_init_cdb(cmd, cdb, GFP_KERNEL))
 533                 return -EINVAL;
 534
 535         cmd->tag = 0;
 536         if (target_cmd_parse_cdb(cmd))
 537                 return -EINVAL;
 538
 539         if (transport_generic_map_mem_to_cmd(cmd, xop->xop_data_sg,
 540                                         xop->xop_data_nents, NULL, 0))
 541                 return -EINVAL;
 542
 543         pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
 544                  " %u\n", cmd->t_data_sg, cmd->t_data_nents);
 545
 546         return 0;
 547 }
 548
 549 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
 550 {
 551         struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
 552         sense_reason_t sense_rc;
 553
 554         sense_rc = transport_generic_new_cmd(se_cmd);
 555         if (sense_rc)
 556                 return -EINVAL;
 557
 558         if (se_cmd->data_direction == DMA_TO_DEVICE)
 559                 target_execute_cmd(se_cmd);
 560
 561         wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
 562
 563         pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
 564                         se_cmd->scsi_status);
 565
 566         return (se_cmd->scsi_status) ? -EINVAL : 0;
 567 }
 568
 569 static int target_xcopy_read_source(
 570         struct se_cmd *ec_cmd,
 571         struct xcopy_op *xop,
 572         struct se_device *src_dev,
 573         sector_t src_lba,
 574         u32 src_bytes)
 575 {
 576         struct xcopy_pt_cmd xpt_cmd;
 577         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 578         u32 transfer_length_block = src_bytes / src_dev->dev_attrib.block_size;
 579         int rc;
 580         unsigned char cdb[16];
 581         bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
 582
 583         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 584         init_completion(&xpt_cmd.xpt_passthrough_sem);
 585
 586         memset(&cdb[0], 0, 16);
 587         cdb[0] = READ_16;
 588         put_unaligned_be64(src_lba, &cdb[2]);
 589         put_unaligned_be32(transfer_length_block, &cdb[10]);
 590         pr_debug("XCOPY: Built READ_16: LBA: %llu Blocks: %u Length: %u\n",
 591                 (unsigned long long)src_lba, transfer_length_block, src_bytes);
 592
 593         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, src_bytes,
 594                           DMA_FROM_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0,
 595                           NULL);
 596         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, src_dev, &cdb[0],
 597                                 remote_port);
 598         if (rc < 0) {
 599                 ec_cmd->scsi_status = se_cmd->scsi_status;
 600                 goto out;
 601         }
 602
 603         pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
 604                 " memory\n", xop->xop_data_sg, xop->xop_data_nents);
 605
 606         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 607         if (rc < 0)
 608                 ec_cmd->scsi_status = se_cmd->scsi_status;
 609 out:
 610         transport_generic_free_cmd(se_cmd, 0);
 611         return rc;
 612 }
 613
 614 static int target_xcopy_write_destination(
 615         struct se_cmd *ec_cmd,
 616         struct xcopy_op *xop,
 617         struct se_device *dst_dev,
 618         sector_t dst_lba,
 619         u32 dst_bytes)
 620 {
 621         struct xcopy_pt_cmd xpt_cmd;
 622         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 623         u32 transfer_length_block = dst_bytes / dst_dev->dev_attrib.block_size;
 624         int rc;
 625         unsigned char cdb[16];
 626         bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
 627
 628         memset(&xpt_cmd, 0, sizeof(xpt_cmd));
 629         init_completion(&xpt_cmd.xpt_passthrough_sem);
 630
 631         memset(&cdb[0], 0, 16);
 632         cdb[0] = WRITE_16;
 633         put_unaligned_be64(dst_lba, &cdb[2]);
 634         put_unaligned_be32(transfer_length_block, &cdb[10]);
 635         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Blocks: %u Length: %u\n",
 636                 (unsigned long long)dst_lba, transfer_length_block, dst_bytes);
 637
 638         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, dst_bytes,
 639                           DMA_TO_DEVICE, 0, &xpt_cmd.sense_buffer[0], 0,
 640                           NULL);
 641         rc = target_xcopy_setup_pt_cmd(&xpt_cmd, xop, dst_dev, &cdb[0],
 642                                 remote_port);
 643         if (rc < 0) {
 644                 ec_cmd->scsi_status = se_cmd->scsi_status;
 645                 goto out;
 646         }
 647
 648         rc = target_xcopy_issue_pt_cmd(&xpt_cmd);
 649         if (rc < 0)
 650                 ec_cmd->scsi_status = se_cmd->scsi_status;
 651 out:
 652         transport_generic_free_cmd(se_cmd, 0);
 653         return rc;
 654 }
 655
 656 static void target_xcopy_do_work(struct work_struct *work)
 657 {
 658         struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
 659         struct se_cmd *ec_cmd = xop->xop_se_cmd;
 660         struct se_device *src_dev, *dst_dev;
 661         sector_t src_lba, dst_lba, end_lba;
 662         unsigned long long max_bytes, max_bytes_src, max_bytes_dst, max_blocks;
 663         int rc = 0;
 664         unsigned short nolb;
 665         unsigned int copied_bytes = 0;
 666         sense_reason_t sense_rc;
 667
 668         sense_rc = target_parse_xcopy_cmd(xop);
 669         if (sense_rc != TCM_NO_SENSE)
 670                 goto err_free;
 671
 672         if (WARN_ON_ONCE(!xop->src_dev) || WARN_ON_ONCE(!xop->dst_dev)) {
 673                 sense_rc = TCM_INVALID_PARAMETER_LIST;
 674                 goto err_free;
 675         }
 676
 677         src_dev = xop->src_dev;
 678         dst_dev = xop->dst_dev;
 679         src_lba = xop->src_lba;
 680         dst_lba = xop->dst_lba;
 681         nolb = xop->nolb;
 682         end_lba = src_lba + nolb;
 683         /*
 684          * Break up XCOPY I/O into hw_max_sectors * hw_block_size sized
 685          * I/O based on the smallest max_bytes between src_dev + dst_dev
 686          */
 687         max_bytes_src = (unsigned long long) src_dev->dev_attrib.hw_max_sectors *
 688                         src_dev->dev_attrib.hw_block_size;
 689         max_bytes_dst = (unsigned long long) dst_dev->dev_attrib.hw_max_sectors *
 690                         dst_dev->dev_attrib.hw_block_size;
 691
 692         max_bytes = min_t(u64, max_bytes_src, max_bytes_dst);
 693         max_bytes = min_t(u64, max_bytes, XCOPY_MAX_BYTES);
 694
 695         /*
 696          * Using shift instead of the division because otherwise GCC
 697          * generates __udivdi3 that is missing on i386
 698          */
 699         max_blocks = max_bytes >> ilog2(src_dev->dev_attrib.block_size);
 700
 701         pr_debug("%s: nolb: %u, max_blocks: %llu end_lba: %llu\n", __func__,
 702                         nolb, max_blocks, (unsigned long long)end_lba);
 703         pr_debug("%s: Starting src_lba: %llu, dst_lba: %llu\n", __func__,
 704                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
 705
 706         while (nolb) {
 707                 u32 cur_bytes = min_t(u64, max_bytes, nolb * src_dev->dev_attrib.block_size);
 708                 unsigned short cur_nolb = cur_bytes / src_dev->dev_attrib.block_size;
 709
 710                 if (cur_bytes != xop->xop_data_bytes) {
 711                         /*
 712                          * (Re)allocate a buffer large enough to hold the XCOPY
 713                          * I/O size, which can be reused each read / write loop.
 714                          */
 715                         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 716                         rc = target_alloc_sgl(&xop->xop_data_sg,
 717                                               &xop->xop_data_nents,
 718                                               cur_bytes,
 719                                               false, false);
 720                         if (rc < 0)
 721                                 goto out;
 722                         xop->xop_data_bytes = cur_bytes;
 723                 }
 724
 725                 pr_debug("%s: Calling read src_dev: %p src_lba: %llu, cur_nolb: %hu\n",
 726                                 __func__, src_dev, (unsigned long long)src_lba, cur_nolb);
 727
 728                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_bytes);
 729                 if (rc < 0)
 730                         goto out;
 731
 732                 src_lba += cur_bytes / src_dev->dev_attrib.block_size;
 733                 pr_debug("%s: Incremented READ src_lba to %llu\n", __func__,
 734                                 (unsigned long long)src_lba);
 735
 736                 pr_debug("%s: Calling write dst_dev: %p dst_lba: %llu, cur_nolb: %u\n",
 737                                 __func__, dst_dev, (unsigned long long)dst_lba, cur_nolb);
 738
 739                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
 740                                                 dst_lba, cur_bytes);
 741                 if (rc < 0)
 742                         goto out;
 743
 744                 dst_lba += cur_bytes / dst_dev->dev_attrib.block_size;
 745                 pr_debug("%s: Incremented WRITE dst_lba to %llu\n", __func__,
 746                                 (unsigned long long)dst_lba);
 747
 748                 copied_bytes += cur_bytes;
 749                 nolb -= cur_bytes / src_dev->dev_attrib.block_size;
 750         }
 751
 752         xcopy_pt_undepend_remotedev(xop);
 753         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 754         kfree(xop);
 755
 756         pr_debug("%s: Final src_lba: %llu, dst_lba: %llu\n", __func__,
 757                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
 758         pr_debug("%s: Blocks copied: %u, Bytes Copied: %u\n", __func__,
 759                 copied_bytes / dst_dev->dev_attrib.block_size, copied_bytes);
 760
 761         pr_debug("%s: Setting X-COPY GOOD status -> sending response\n", __func__);
 762         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
 763         return;
 764
 765 out:
 766         /*
 767          * The XCOPY command was aborted after some data was transferred.
 768          * Terminate command with CHECK CONDITION status, with the sense key
 769          * set to COPY ABORTED.
 770          */
 771         sense_rc = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
 772         xcopy_pt_undepend_remotedev(xop);
 773         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 774
 775 err_free:
 776         kfree(xop);
 777         pr_warn_ratelimited("%s: rc: %d, sense: %u, XCOPY operation failed\n",
 778                            __func__, rc, sense_rc);
 779         target_complete_cmd_with_sense(ec_cmd, SAM_STAT_CHECK_CONDITION, sense_rc);
 780 }
 781
 782 /*
 783  * Returns TCM_NO_SENSE upon success or a sense code != TCM_NO_SENSE if parsing
 784  * fails.
 785  */
 786 static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop)
 787 {
 788         struct se_cmd *se_cmd = xop->xop_se_cmd;
 789         unsigned char *p = NULL, *seg_desc;
 790         unsigned int list_id, list_id_usage, sdll, inline_dl;
 791         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
 792         int rc;
 793         unsigned short tdll;
 794
 795         p = transport_kmap_data_sg(se_cmd);
 796         if (!p) {
 797                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
 798                 return TCM_OUT_OF_RESOURCES;
 799         }
 800
 801         list_id = p[0];
 802         list_id_usage = (p[1] & 0x18) >> 3;
 803
 804         /*
 805          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
 806          */
 807         tdll = get_unaligned_be16(&p[2]);
 808         sdll = get_unaligned_be32(&p[8]);
 809         if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
 810                 pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
 811                        tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
 812                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 813                 goto out;
 814         }
 815
 816         inline_dl = get_unaligned_be32(&p[12]);
 817         if (inline_dl != 0) {
 818                 pr_err("XCOPY with non zero inline data length\n");
 819                 goto out;
 820         }
 821
 822         if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
 823                 pr_err("XCOPY parameter truncation: data length %u too small "
 824                         "for tdll: %hu sdll: %u inline_dl: %u\n",
 825                         se_cmd->data_length, tdll, sdll, inline_dl);
 826                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 827                 goto out;
 828         }
 829
 830         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
 831                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
 832                 tdll, sdll, inline_dl);
 833
 834         /*
 835          * skip over the target descriptors until segment descriptors
 836          * have been passed - CSCD ids are needed to determine src and dest.
 837          */
 838         seg_desc = &p[16] + tdll;
 839
 840         rc = target_xcopy_parse_segment_descriptors(xop, seg_desc, sdll, &ret);
 841         if (rc <= 0)
 842                 goto out;
 843
 844         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
 845                                 rc * XCOPY_SEGMENT_DESC_LEN);
 846
 847         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
 848         if (rc <= 0)
 849                 goto out;
 850
 851         if (xop->src_dev->dev_attrib.block_size !=
 852             xop->dst_dev->dev_attrib.block_size) {
 853                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
 854                        " block_size: %u currently unsupported\n",
 855                         xop->src_dev->dev_attrib.block_size,
 856                         xop->dst_dev->dev_attrib.block_size);
 857                 xcopy_pt_undepend_remotedev(xop);
 858                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 859                 goto out;
 860         }
 861
 862         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
 863                                 rc * XCOPY_TARGET_DESC_LEN);
 864         transport_kunmap_data_sg(se_cmd);
 865         return TCM_NO_SENSE;
 866
 867 out:
 868         if (p)
 869                 transport_kunmap_data_sg(se_cmd);
 870         return ret;
 871 }
 872
 873 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
 874 {
 875         struct se_device *dev = se_cmd->se_dev;
 876         struct xcopy_op *xop;
 877         unsigned int sa;
 878
 879         if (!dev->dev_attrib.emulate_3pc) {
 880                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
 881                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 882         }
 883
 884         sa = se_cmd->t_task_cdb[1] & 0x1f;
 885         if (sa != 0x00) {
 886                 pr_err("EXTENDED_COPY(LID4) not supported\n");
 887                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 888         }
 889
 890         if (se_cmd->data_length == 0) {
 891                 target_complete_cmd(se_cmd, SAM_STAT_GOOD);
 892                 return TCM_NO_SENSE;
 893         }
 894         if (se_cmd->data_length < XCOPY_HDR_LEN) {
 895                 pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
 896                                 se_cmd->data_length, XCOPY_HDR_LEN);
 897                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
 898         }
 899
 900         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
 901         if (!xop)
 902                 goto err;
 903         xop->xop_se_cmd = se_cmd;
 904         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
 905         if (WARN_ON_ONCE(!queue_work(xcopy_wq, &xop->xop_work)))
 906                 goto free;
 907         return TCM_NO_SENSE;
 908
 909 free:
 910         kfree(xop);
 911
 912 err:
 913         return TCM_OUT_OF_RESOURCES;
 914 }
 915
 916 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
 917 {
 918         unsigned char *p;
 919
 920         p = transport_kmap_data_sg(se_cmd);
 921         if (!p) {
 922                 pr_err("transport_kmap_data_sg failed in"
 923                        " target_rcr_operating_parameters\n");
 924                 return TCM_OUT_OF_RESOURCES;
 925         }
 926
 927         if (se_cmd->data_length < 54) {
 928                 pr_err("Receive Copy Results Op Parameters length"
 929                        " too small: %u\n", se_cmd->data_length);
 930                 transport_kunmap_data_sg(se_cmd);
 931                 return TCM_INVALID_CDB_FIELD;
 932         }
 933         /*
 934          * Set SNLID=1 (Supports no List ID)
 935          */
 936         p[4] = 0x1;
 937         /*
 938          * MAXIMUM TARGET DESCRIPTOR COUNT
 939          */
 940         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
 941         /*
 942          * MAXIMUM SEGMENT DESCRIPTOR COUNT
 943          */
 944         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
 945         /*
 946          * MAXIMUM DESCRIPTOR LIST LENGTH
 947          */
 948         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
 949         /*
 950          * MAXIMUM SEGMENT LENGTH
 951          */
 952         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
 953         /*
 954          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
 955          */
 956         put_unaligned_be32(0x0, &p[20]);
 957         /*
 958          * HELD DATA LIMIT
 959          */
 960         put_unaligned_be32(0x0, &p[24]);
 961         /*
 962          * MAXIMUM STREAM DEVICE TRANSFER SIZE
 963          */
 964         put_unaligned_be32(0x0, &p[28]);
 965         /*
 966          * TOTAL CONCURRENT COPIES
 967          */
 968         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
 969         /*
 970          * MAXIMUM CONCURRENT COPIES
 971          */
 972         p[36] = RCR_OP_MAX_CONCURR_COPIES;
 973         /*
 974          * DATA SEGMENT GRANULARITY (log 2)
 975          */
 976         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
 977         /*
 978          * INLINE DATA GRANULARITY log 2)
 979          */
 980         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
 981         /*
 982          * HELD DATA GRANULARITY
 983          */
 984         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
 985         /*
 986          * IMPLEMENTED DESCRIPTOR LIST LENGTH
 987          */
 988         p[43] = 0x2;
 989         /*
 990          * List of implemented descriptor type codes (ordered)
 991          */
 992         p[44] = 0x02; /* Copy Block to Block device */
 993         p[45] = 0xe4; /* Identification descriptor target descriptor */
 994
 995         /*
 996          * AVAILABLE DATA (n-3)
 997          */
 998         put_unaligned_be32(42, &p[0]);
 999
1000         transport_kunmap_data_sg(se_cmd);
1001         target_complete_cmd(se_cmd, SAM_STAT_GOOD);
1002
1003         return TCM_NO_SENSE;
1004 }
1005
1006 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1007 {
1008         unsigned char *cdb = &se_cmd->t_task_cdb[0];
1009         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1010         struct se_device *dev = se_cmd->se_dev;
1011         sense_reason_t rc = TCM_NO_SENSE;
1012
1013         if (!dev->dev_attrib.emulate_3pc) {
1014                 pr_debug("Third-party copy operations explicitly disabled\n");
1015                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1016         }
1017
1018         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1019                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1020
1021         if (list_id != 0) {
1022                 pr_err("Receive Copy Results with non zero list identifier"
1023                        " not supported\n");
1024                 return TCM_INVALID_CDB_FIELD;
1025         }
1026
1027         switch (sa) {
1028         case RCR_SA_OPERATING_PARAMETERS:
1029                 rc = target_rcr_operating_parameters(se_cmd);
1030                 break;
1031         case RCR_SA_COPY_STATUS:
1032         case RCR_SA_RECEIVE_DATA:
1033         case RCR_SA_FAILED_SEGMENT_DETAILS:
1034         default:
1035                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1036                 return TCM_INVALID_CDB_FIELD;
1037         }
1038
1039         return rc;
1040 }