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         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_bytes)
 586 {
 587         struct xcopy_pt_cmd xpt_cmd;
 588         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 589         u32 transfer_length_block = src_bytes / 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(transfer_length_block, &cdb[10]);
 601         pr_debug("XCOPY: Built READ_16: LBA: %llu Blocks: %u Length: %u\n",
 602                 (unsigned long long)src_lba, transfer_length_block, src_bytes);
 603
 604         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, src_bytes,
 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_bytes)
 631 {
 632         struct xcopy_pt_cmd xpt_cmd;
 633         struct se_cmd *se_cmd = &xpt_cmd.se_cmd;
 634         u32 transfer_length_block = dst_bytes / 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(transfer_length_block, &cdb[10]);
 646         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Blocks: %u Length: %u\n",
 647                 (unsigned long long)dst_lba, transfer_length_block, dst_bytes);
 648
 649         __target_init_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, dst_bytes,
 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 long long max_bytes, max_bytes_src, max_bytes_dst, max_blocks;
 674         int rc = 0;
 675         unsigned short nolb;
 676         unsigned int copied_bytes = 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 * hw_block_size sized
 696          * I/O based on the smallest max_bytes between src_dev + dst_dev
 697          */
 698         max_bytes_src = (unsigned long long) src_dev->dev_attrib.hw_max_sectors *
 699                         src_dev->dev_attrib.hw_block_size;
 700         max_bytes_dst = (unsigned long long) dst_dev->dev_attrib.hw_max_sectors *
 701                         dst_dev->dev_attrib.hw_block_size;
 702
 703         max_bytes = min_t(u64, max_bytes_src, max_bytes_dst);
 704         max_bytes = min_t(u64, max_bytes, XCOPY_MAX_BYTES);
 705
 706         /*
 707          * Using shift instead of the division because otherwise GCC
 708          * generates __udivdi3 that is missing on i386
 709          */
 710         max_blocks = max_bytes >> ilog2(src_dev->dev_attrib.block_size);
 711
 712         pr_debug("%s: nolb: %u, max_blocks: %llu end_lba: %llu\n", __func__,
 713                         nolb, max_blocks, (unsigned long long)end_lba);
 714         pr_debug("%s: Starting src_lba: %llu, dst_lba: %llu\n", __func__,
 715                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
 716
 717         while (nolb) {
 718                 u32 cur_bytes = min_t(u64, max_bytes, nolb * src_dev->dev_attrib.block_size);
 719                 unsigned short cur_nolb = cur_bytes / src_dev->dev_attrib.block_size;
 720
 721                 if (cur_bytes != xop->xop_data_bytes) {
 722                         /*
 723                          * (Re)allocate a buffer large enough to hold the XCOPY
 724                          * I/O size, which can be reused each read / write loop.
 725                          */
 726                         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 727                         rc = target_alloc_sgl(&xop->xop_data_sg,
 728                                               &xop->xop_data_nents,
 729                                               cur_bytes,
 730                                               false, false);
 731                         if (rc < 0)
 732                                 goto out;
 733                         xop->xop_data_bytes = cur_bytes;
 734                 }
 735
 736                 pr_debug("%s: Calling read src_dev: %p src_lba: %llu, cur_nolb: %hu\n",
 737                                 __func__, src_dev, (unsigned long long)src_lba, cur_nolb);
 738
 739                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_bytes);
 740                 if (rc < 0)
 741                         goto out;
 742
 743                 src_lba += cur_bytes / src_dev->dev_attrib.block_size;
 744                 pr_debug("%s: Incremented READ src_lba to %llu\n", __func__,
 745                                 (unsigned long long)src_lba);
 746
 747                 pr_debug("%s: Calling write dst_dev: %p dst_lba: %llu, cur_nolb: %u\n",
 748                                 __func__, dst_dev, (unsigned long long)dst_lba, cur_nolb);
 749
 750                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
 751                                                 dst_lba, cur_bytes);
 752                 if (rc < 0)
 753                         goto out;
 754
 755                 dst_lba += cur_bytes / dst_dev->dev_attrib.block_size;
 756                 pr_debug("%s: Incremented WRITE dst_lba to %llu\n", __func__,
 757                                 (unsigned long long)dst_lba);
 758
 759                 copied_bytes += cur_bytes;
 760                 nolb -= cur_bytes / src_dev->dev_attrib.block_size;
 761         }
 762
 763         xcopy_pt_undepend_remotedev(xop);
 764         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 765         kfree(xop);
 766
 767         pr_debug("%s: Final src_lba: %llu, dst_lba: %llu\n", __func__,
 768                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
 769         pr_debug("%s: Blocks copied: %u, Bytes Copied: %u\n", __func__,
 770                 copied_bytes / dst_dev->dev_attrib.block_size, copied_bytes);
 771
 772         pr_debug("%s: Setting X-COPY GOOD status -> sending response\n", __func__);
 773         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
 774         return;
 775
 776 out:
 777         /*
 778          * The XCOPY command was aborted after some data was transferred.
 779          * Terminate command with CHECK CONDITION status, with the sense key
 780          * set to COPY ABORTED.
 781          */
 782         sense_rc = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
 783         xcopy_pt_undepend_remotedev(xop);
 784         target_free_sgl(xop->xop_data_sg, xop->xop_data_nents);
 785
 786 err_free:
 787         kfree(xop);
 788         pr_warn_ratelimited("%s: rc: %d, sense: %u, XCOPY operation failed\n",
 789                            __func__, rc, sense_rc);
 790         target_complete_cmd_with_sense(ec_cmd, SAM_STAT_CHECK_CONDITION, sense_rc);
 791 }
 792
 793 /*
 794  * Returns TCM_NO_SENSE upon success or a sense code != TCM_NO_SENSE if parsing
 795  * fails.
 796  */
 797 static sense_reason_t target_parse_xcopy_cmd(struct xcopy_op *xop)
 798 {
 799         struct se_cmd *se_cmd = xop->xop_se_cmd;
 800         unsigned char *p = NULL, *seg_desc;
 801         unsigned int list_id, list_id_usage, sdll, inline_dl;
 802         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
 803         int rc;
 804         unsigned short tdll;
 805
 806         p = transport_kmap_data_sg(se_cmd);
 807         if (!p) {
 808                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
 809                 return TCM_OUT_OF_RESOURCES;
 810         }
 811
 812         list_id = p[0];
 813         list_id_usage = (p[1] & 0x18) >> 3;
 814
 815         /*
 816          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
 817          */
 818         tdll = get_unaligned_be16(&p[2]);
 819         sdll = get_unaligned_be32(&p[8]);
 820         if (tdll + sdll > RCR_OP_MAX_DESC_LIST_LEN) {
 821                 pr_err("XCOPY descriptor list length %u exceeds maximum %u\n",
 822                        tdll + sdll, RCR_OP_MAX_DESC_LIST_LEN);
 823                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 824                 goto out;
 825         }
 826
 827         inline_dl = get_unaligned_be32(&p[12]);
 828         if (inline_dl != 0) {
 829                 pr_err("XCOPY with non zero inline data length\n");
 830                 goto out;
 831         }
 832
 833         if (se_cmd->data_length < (XCOPY_HDR_LEN + tdll + sdll + inline_dl)) {
 834                 pr_err("XCOPY parameter truncation: data length %u too small "
 835                         "for tdll: %hu sdll: %u inline_dl: %u\n",
 836                         se_cmd->data_length, tdll, sdll, inline_dl);
 837                 ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
 838                 goto out;
 839         }
 840
 841         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
 842                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
 843                 tdll, sdll, inline_dl);
 844
 845         /*
 846          * skip over the target descriptors until segment descriptors
 847          * have been passed - CSCD ids are needed to determine src and dest.
 848          */
 849         seg_desc = &p[16] + tdll;
 850
 851         rc = target_xcopy_parse_segment_descriptors(xop, seg_desc, sdll, &ret);
 852         if (rc <= 0)
 853                 goto out;
 854
 855         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
 856                                 rc * XCOPY_SEGMENT_DESC_LEN);
 857
 858         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
 859         if (rc <= 0)
 860                 goto out;
 861
 862         if (xop->src_dev->dev_attrib.block_size !=
 863             xop->dst_dev->dev_attrib.block_size) {
 864                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
 865                        " block_size: %u currently unsupported\n",
 866                         xop->src_dev->dev_attrib.block_size,
 867                         xop->dst_dev->dev_attrib.block_size);
 868                 xcopy_pt_undepend_remotedev(xop);
 869                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 870                 goto out;
 871         }
 872
 873         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
 874                                 rc * XCOPY_TARGET_DESC_LEN);
 875         transport_kunmap_data_sg(se_cmd);
 876         return TCM_NO_SENSE;
 877
 878 out:
 879         if (p)
 880                 transport_kunmap_data_sg(se_cmd);
 881         return ret;
 882 }
 883
 884 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
 885 {
 886         struct se_device *dev = se_cmd->se_dev;
 887         struct xcopy_op *xop;
 888         unsigned int sa;
 889
 890         if (!dev->dev_attrib.emulate_3pc) {
 891                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
 892                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 893         }
 894
 895         sa = se_cmd->t_task_cdb[1] & 0x1f;
 896         if (sa != 0x00) {
 897                 pr_err("EXTENDED_COPY(LID4) not supported\n");
 898                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 899         }
 900
 901         if (se_cmd->data_length == 0) {
 902                 target_complete_cmd(se_cmd, SAM_STAT_GOOD);
 903                 return TCM_NO_SENSE;
 904         }
 905         if (se_cmd->data_length < XCOPY_HDR_LEN) {
 906                 pr_err("XCOPY parameter truncation: length %u < hdr_len %u\n",
 907                                 se_cmd->data_length, XCOPY_HDR_LEN);
 908                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
 909         }
 910
 911         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
 912         if (!xop)
 913                 goto err;
 914         xop->xop_se_cmd = se_cmd;
 915         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
 916         if (WARN_ON_ONCE(!queue_work(xcopy_wq, &xop->xop_work)))
 917                 goto free;
 918         return TCM_NO_SENSE;
 919
 920 free:
 921         kfree(xop);
 922
 923 err:
 924         return TCM_OUT_OF_RESOURCES;
 925 }
 926
 927 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
 928 {
 929         unsigned char *p;
 930
 931         p = transport_kmap_data_sg(se_cmd);
 932         if (!p) {
 933                 pr_err("transport_kmap_data_sg failed in"
 934                        " target_rcr_operating_parameters\n");
 935                 return TCM_OUT_OF_RESOURCES;
 936         }
 937
 938         if (se_cmd->data_length < 54) {
 939                 pr_err("Receive Copy Results Op Parameters length"
 940                        " too small: %u\n", se_cmd->data_length);
 941                 transport_kunmap_data_sg(se_cmd);
 942                 return TCM_INVALID_CDB_FIELD;
 943         }
 944         /*
 945          * Set SNLID=1 (Supports no List ID)
 946          */
 947         p[4] = 0x1;
 948         /*
 949          * MAXIMUM TARGET DESCRIPTOR COUNT
 950          */
 951         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
 952         /*
 953          * MAXIMUM SEGMENT DESCRIPTOR COUNT
 954          */
 955         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
 956         /*
 957          * MAXIMUM DESCRIPTOR LIST LENGTH
 958          */
 959         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
 960         /*
 961          * MAXIMUM SEGMENT LENGTH
 962          */
 963         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
 964         /*
 965          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
 966          */
 967         put_unaligned_be32(0x0, &p[20]);
 968         /*
 969          * HELD DATA LIMIT
 970          */
 971         put_unaligned_be32(0x0, &p[24]);
 972         /*
 973          * MAXIMUM STREAM DEVICE TRANSFER SIZE
 974          */
 975         put_unaligned_be32(0x0, &p[28]);
 976         /*
 977          * TOTAL CONCURRENT COPIES
 978          */
 979         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
 980         /*
 981          * MAXIMUM CONCURRENT COPIES
 982          */
 983         p[36] = RCR_OP_MAX_CONCURR_COPIES;
 984         /*
 985          * DATA SEGMENT GRANULARITY (log 2)
 986          */
 987         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
 988         /*
 989          * INLINE DATA GRANULARITY log 2)
 990          */
 991         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
 992         /*
 993          * HELD DATA GRANULARITY
 994          */
 995         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
 996         /*
 997          * IMPLEMENTED DESCRIPTOR LIST LENGTH
 998          */
 999         p[43] = 0x2;
1000         /*
1001          * List of implemented descriptor type codes (ordered)
1002          */
1003         p[44] = 0x02; /* Copy Block to Block device */
1004         p[45] = 0xe4; /* Identification descriptor target descriptor */
1005
1006         /*
1007          * AVAILABLE DATA (n-3)
1008          */
1009         put_unaligned_be32(42, &p[0]);
1010
1011         transport_kunmap_data_sg(se_cmd);
1012         target_complete_cmd(se_cmd, SAM_STAT_GOOD);
1013
1014         return TCM_NO_SENSE;
1015 }
1016
1017 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1018 {
1019         unsigned char *cdb = &se_cmd->t_task_cdb[0];
1020         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1021         struct se_device *dev = se_cmd->se_dev;
1022         sense_reason_t rc = TCM_NO_SENSE;
1023
1024         if (!dev->dev_attrib.emulate_3pc) {
1025                 pr_debug("Third-party copy operations explicitly disabled\n");
1026                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1027         }
1028
1029         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1030                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1031
1032         if (list_id != 0) {
1033                 pr_err("Receive Copy Results with non zero list identifier"
1034                        " not supported\n");
1035                 return TCM_INVALID_CDB_FIELD;
1036         }
1037
1038         switch (sa) {
1039         case RCR_SA_OPERATING_PARAMETERS:
1040                 rc = target_rcr_operating_parameters(se_cmd);
1041                 break;
1042         case RCR_SA_COPY_STATUS:
1043         case RCR_SA_RECEIVE_DATA:
1044         case RCR_SA_FAILED_SEGMENT_DETAILS:
1045         default:
1046                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1047                 return TCM_INVALID_CDB_FIELD;
1048         }
1049
1050         return rc;
1051 }