drivers/target/target_core_xcopy.c

   1 /*******************************************************************************
   2  * Filename: target_core_xcopy.c
   3  *
   4  * This file contains support for SPC-4 Extended-Copy offload with generic
   5  * TCM backends.
   6  *
   7  * Copyright (c) 2011-2013 Datera, Inc. All rights reserved.
   8  *
   9  * Author:
  10  * Nicholas A. Bellinger <nab@daterainc.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  ******************************************************************************/
  23
  24 #include <linux/slab.h>
  25 #include <linux/spinlock.h>
  26 #include <linux/list.h>
  27 #include <linux/configfs.h>
  28 #include <scsi/scsi_proto.h>
  29 #include <asm/unaligned.h>
  30
  31 #include <target/target_core_base.h>
  32 #include <target/target_core_backend.h>
  33 #include <target/target_core_fabric.h>
  34
  35 #include "target_core_internal.h"
  36 #include "target_core_pr.h"
  37 #include "target_core_ua.h"
  38 #include "target_core_xcopy.h"
  39
  40 static struct workqueue_struct *xcopy_wq = NULL;
  41
  42 static int target_xcopy_gen_naa_ieee(struct se_device *dev, unsigned char *buf)
  43 {
  44         int off = 0;
  45
  46         buf[off++] = (0x6 << 4);
  47         buf[off++] = 0x01;
  48         buf[off++] = 0x40;
  49         buf[off] = (0x5 << 4);
  50
  51         spc_parse_naa_6h_vendor_specific(dev, &buf[off]);
  52         return 0;
  53 }
  54
  55 static int target_xcopy_locate_se_dev_e4(struct se_cmd *se_cmd, struct xcopy_op *xop,
  56                                         bool src)
  57 {
  58         struct se_device *se_dev;
  59         unsigned char tmp_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN], *dev_wwn;
  60         int rc;
  61
  62         if (src)
  63                 dev_wwn = &xop->dst_tid_wwn[0];
  64         else
  65                 dev_wwn = &xop->src_tid_wwn[0];
  66
  67         mutex_lock(&g_device_mutex);
  68         list_for_each_entry(se_dev, &g_device_list, g_dev_node) {
  69
  70                 if (!se_dev->dev_attrib.emulate_3pc)
  71                         continue;
  72
  73                 memset(&tmp_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
  74                 target_xcopy_gen_naa_ieee(se_dev, &tmp_dev_wwn[0]);
  75
  76                 rc = memcmp(&tmp_dev_wwn[0], dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN);
  77                 if (rc != 0)
  78                         continue;
  79
  80                 if (src) {
  81                         xop->dst_dev = se_dev;
  82                         pr_debug("XCOPY 0xe4: Setting xop->dst_dev: %p from located"
  83                                 " se_dev\n", xop->dst_dev);
  84                 } else {
  85                         xop->src_dev = se_dev;
  86                         pr_debug("XCOPY 0xe4: Setting xop->src_dev: %p from located"
  87                                 " se_dev\n", xop->src_dev);
  88                 }
  89
  90                 rc = target_depend_item(&se_dev->dev_group.cg_item);
  91                 if (rc != 0) {
  92                         pr_err("configfs_depend_item attempt failed:"
  93                                 " %d for se_dev: %p\n", rc, se_dev);
  94                         mutex_unlock(&g_device_mutex);
  95                         return rc;
  96                 }
  97
  98                 pr_debug("Called configfs_depend_item for se_dev: %p"
  99                         " se_dev->se_dev_group: %p\n", se_dev,
 100                         &se_dev->dev_group);
 101
 102                 mutex_unlock(&g_device_mutex);
 103                 return 0;
 104         }
 105         mutex_unlock(&g_device_mutex);
 106
 107         pr_debug_ratelimited("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n");
 108         return -EINVAL;
 109 }
 110
 111 static int target_xcopy_parse_tiddesc_e4(struct se_cmd *se_cmd, struct xcopy_op *xop,
 112                                 unsigned char *p, bool src)
 113 {
 114         unsigned char *desc = p;
 115         unsigned short ript;
 116         u8 desig_len;
 117         /*
 118          * Extract RELATIVE INITIATOR PORT IDENTIFIER
 119          */
 120         ript = get_unaligned_be16(&desc[2]);
 121         pr_debug("XCOPY 0xe4: RELATIVE INITIATOR PORT IDENTIFIER: %hu\n", ript);
 122         /*
 123          * Check for supported code set, association, and designator type
 124          */
 125         if ((desc[4] & 0x0f) != 0x1) {
 126                 pr_err("XCOPY 0xe4: code set of non binary type not supported\n");
 127                 return -EINVAL;
 128         }
 129         if ((desc[5] & 0x30) != 0x00) {
 130                 pr_err("XCOPY 0xe4: association other than LUN not supported\n");
 131                 return -EINVAL;
 132         }
 133         if ((desc[5] & 0x0f) != 0x3) {
 134                 pr_err("XCOPY 0xe4: designator type unsupported: 0x%02x\n",
 135                                 (desc[5] & 0x0f));
 136                 return -EINVAL;
 137         }
 138         /*
 139          * Check for matching 16 byte length for NAA IEEE Registered Extended
 140          * Assigned designator
 141          */
 142         desig_len = desc[7];
 143         if (desig_len != 16) {
 144                 pr_err("XCOPY 0xe4: invalid desig_len: %d\n", (int)desig_len);
 145                 return -EINVAL;
 146         }
 147         pr_debug("XCOPY 0xe4: desig_len: %d\n", (int)desig_len);
 148         /*
 149          * Check for NAA IEEE Registered Extended Assigned header..
 150          */
 151         if ((desc[8] & 0xf0) != 0x60) {
 152                 pr_err("XCOPY 0xe4: Unsupported DESIGNATOR TYPE: 0x%02x\n",
 153                                         (desc[8] & 0xf0));
 154                 return -EINVAL;
 155         }
 156
 157         if (src) {
 158                 memcpy(&xop->src_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
 159                 /*
 160                  * Determine if the source designator matches the local device
 161                  */
 162                 if (!memcmp(&xop->local_dev_wwn[0], &xop->src_tid_wwn[0],
 163                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
 164                         xop->op_origin = XCOL_SOURCE_RECV_OP;
 165                         xop->src_dev = se_cmd->se_dev;
 166                         pr_debug("XCOPY 0xe4: Set xop->src_dev %p from source"
 167                                         " received xop\n", xop->src_dev);
 168                 }
 169         } else {
 170                 memcpy(&xop->dst_tid_wwn[0], &desc[8], XCOPY_NAA_IEEE_REGEX_LEN);
 171                 /*
 172                  * Determine if the destination designator matches the local device
 173                  */
 174                 if (!memcmp(&xop->local_dev_wwn[0], &xop->dst_tid_wwn[0],
 175                                 XCOPY_NAA_IEEE_REGEX_LEN)) {
 176                         xop->op_origin = XCOL_DEST_RECV_OP;
 177                         xop->dst_dev = se_cmd->se_dev;
 178                         pr_debug("XCOPY 0xe4: Set xop->dst_dev: %p from destination"
 179                                 " received xop\n", xop->dst_dev);
 180                 }
 181         }
 182
 183         return 0;
 184 }
 185
 186 static int target_xcopy_parse_target_descriptors(struct se_cmd *se_cmd,
 187                                 struct xcopy_op *xop, unsigned char *p,
 188                                 unsigned short tdll, sense_reason_t *sense_ret)
 189 {
 190         struct se_device *local_dev = se_cmd->se_dev;
 191         unsigned char *desc = p;
 192         int offset = tdll % XCOPY_TARGET_DESC_LEN, rc, ret = 0;
 193         unsigned short start = 0;
 194         bool src = true;
 195
 196         *sense_ret = TCM_INVALID_PARAMETER_LIST;
 197
 198         if (offset != 0) {
 199                 pr_err("XCOPY target descriptor list length is not"
 200                         " multiple of %d\n", XCOPY_TARGET_DESC_LEN);
 201                 return -EINVAL;
 202         }
 203         if (tdll > 64) {
 204                 pr_err("XCOPY target descriptor supports a maximum"
 205                         " two src/dest descriptors, tdll: %hu too large..\n", tdll);
 206                 return -EINVAL;
 207         }
 208         /*
 209          * Generate an IEEE Registered Extended designator based upon the
 210          * se_device the XCOPY was received upon..
 211          */
 212         memset(&xop->local_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN);
 213         target_xcopy_gen_naa_ieee(local_dev, &xop->local_dev_wwn[0]);
 214
 215         while (start < tdll) {
 216                 /*
 217                  * Check target descriptor identification with 0xE4 type with
 218                  * use VPD 0x83 WWPN matching ..
 219                  */
 220                 switch (desc[0]) {
 221                 case 0xe4:
 222                         rc = target_xcopy_parse_tiddesc_e4(se_cmd, xop,
 223                                                         &desc[0], src);
 224                         if (rc != 0)
 225                                 goto out;
 226                         /*
 227                          * Assume target descriptors are in source -> destination order..
 228                          */
 229                         if (src)
 230                                 src = false;
 231                         else
 232                                 src = true;
 233                         start += XCOPY_TARGET_DESC_LEN;
 234                         desc += XCOPY_TARGET_DESC_LEN;
 235                         ret++;
 236                         break;
 237                 default:
 238                         pr_err("XCOPY unsupported descriptor type code:"
 239                                         " 0x%02x\n", desc[0]);
 240                         goto out;
 241                 }
 242         }
 243
 244         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
 245                 rc = target_xcopy_locate_se_dev_e4(se_cmd, xop, true);
 246         else
 247                 rc = target_xcopy_locate_se_dev_e4(se_cmd, xop, false);
 248         /*
 249          * If a matching IEEE NAA 0x83 descriptor for the requested device
 250          * is not located on this node, return COPY_ABORTED with ASQ/ASQC
 251          * 0x0d/0x02 - COPY_TARGET_DEVICE_NOT_REACHABLE to request the
 252          * initiator to fall back to normal copy method.
 253          */
 254         if (rc < 0) {
 255                 *sense_ret = TCM_COPY_TARGET_DEVICE_NOT_REACHABLE;
 256                 goto out;
 257         }
 258
 259         pr_debug("XCOPY TGT desc: Source dev: %p NAA IEEE WWN: 0x%16phN\n",
 260                  xop->src_dev, &xop->src_tid_wwn[0]);
 261         pr_debug("XCOPY TGT desc: Dest dev: %p NAA IEEE WWN: 0x%16phN\n",
 262                  xop->dst_dev, &xop->dst_tid_wwn[0]);
 263
 264         return ret;
 265
 266 out:
 267         return -EINVAL;
 268 }
 269
 270 static int target_xcopy_parse_segdesc_02(struct se_cmd *se_cmd, struct xcopy_op *xop,
 271                                         unsigned char *p)
 272 {
 273         unsigned char *desc = p;
 274         int dc = (desc[1] & 0x02);
 275         unsigned short desc_len;
 276
 277         desc_len = get_unaligned_be16(&desc[2]);
 278         if (desc_len != 0x18) {
 279                 pr_err("XCOPY segment desc 0x02: Illegal desc_len:"
 280                                 " %hu\n", desc_len);
 281                 return -EINVAL;
 282         }
 283
 284         xop->stdi = get_unaligned_be16(&desc[4]);
 285         xop->dtdi = get_unaligned_be16(&desc[6]);
 286         pr_debug("XCOPY seg desc 0x02: desc_len: %hu stdi: %hu dtdi: %hu, DC: %d\n",
 287                 desc_len, xop->stdi, xop->dtdi, dc);
 288
 289         xop->nolb = get_unaligned_be16(&desc[10]);
 290         xop->src_lba = get_unaligned_be64(&desc[12]);
 291         xop->dst_lba = get_unaligned_be64(&desc[20]);
 292         pr_debug("XCOPY seg desc 0x02: nolb: %hu src_lba: %llu dst_lba: %llu\n",
 293                 xop->nolb, (unsigned long long)xop->src_lba,
 294                 (unsigned long long)xop->dst_lba);
 295
 296         if (dc != 0) {
 297                 xop->dbl = (desc[29] & 0xff) << 16;
 298                 xop->dbl |= (desc[30] & 0xff) << 8;
 299                 xop->dbl |= desc[31] & 0xff;
 300
 301                 pr_debug("XCOPY seg desc 0x02: DC=1 w/ dbl: %u\n", xop->dbl);
 302         }
 303         return 0;
 304 }
 305
 306 static int target_xcopy_parse_segment_descriptors(struct se_cmd *se_cmd,
 307                                 struct xcopy_op *xop, unsigned char *p,
 308                                 unsigned int sdll)
 309 {
 310         unsigned char *desc = p;
 311         unsigned int start = 0;
 312         int offset = sdll % XCOPY_SEGMENT_DESC_LEN, rc, ret = 0;
 313
 314         if (offset != 0) {
 315                 pr_err("XCOPY segment descriptor list length is not"
 316                         " multiple of %d\n", XCOPY_SEGMENT_DESC_LEN);
 317                 return -EINVAL;
 318         }
 319
 320         while (start < sdll) {
 321                 /*
 322                  * Check segment descriptor type code for block -> block
 323                  */
 324                 switch (desc[0]) {
 325                 case 0x02:
 326                         rc = target_xcopy_parse_segdesc_02(se_cmd, xop, desc);
 327                         if (rc < 0)
 328                                 goto out;
 329
 330                         ret++;
 331                         start += XCOPY_SEGMENT_DESC_LEN;
 332                         desc += XCOPY_SEGMENT_DESC_LEN;
 333                         break;
 334                 default:
 335                         pr_err("XCOPY unsupported segment descriptor"
 336                                 "type: 0x%02x\n", desc[0]);
 337                         goto out;
 338                 }
 339         }
 340
 341         return ret;
 342
 343 out:
 344         return -EINVAL;
 345 }
 346
 347 /*
 348  * Start xcopy_pt ops
 349  */
 350
 351 struct xcopy_pt_cmd {
 352         bool remote_port;
 353         struct se_cmd se_cmd;
 354         struct xcopy_op *xcopy_op;
 355         struct completion xpt_passthrough_sem;
 356         unsigned char sense_buffer[TRANSPORT_SENSE_BUFFER];
 357 };
 358
 359 struct se_portal_group xcopy_pt_tpg;
 360 static struct se_session xcopy_pt_sess;
 361 static struct se_node_acl xcopy_pt_nacl;
 362
 363 static char *xcopy_pt_get_fabric_name(void)
 364 {
 365         return "xcopy-pt";
 366 }
 367
 368 static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd)
 369 {
 370         return 0;
 371 }
 372
 373 static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop)
 374 {
 375         struct se_device *remote_dev;
 376
 377         if (xop->op_origin == XCOL_SOURCE_RECV_OP)
 378                 remote_dev = xop->dst_dev;
 379         else
 380                 remote_dev = xop->src_dev;
 381
 382         pr_debug("Calling configfs_undepend_item for"
 383                   " remote_dev: %p remote_dev->dev_group: %p\n",
 384                   remote_dev, &remote_dev->dev_group.cg_item);
 385
 386         target_undepend_item(&remote_dev->dev_group.cg_item);
 387 }
 388
 389 static void xcopy_pt_release_cmd(struct se_cmd *se_cmd)
 390 {
 391         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 392                                 struct xcopy_pt_cmd, se_cmd);
 393
 394         kfree(xpt_cmd);
 395 }
 396
 397 static int xcopy_pt_check_stop_free(struct se_cmd *se_cmd)
 398 {
 399         struct xcopy_pt_cmd *xpt_cmd = container_of(se_cmd,
 400                                 struct xcopy_pt_cmd, se_cmd);
 401
 402         complete(&xpt_cmd->xpt_passthrough_sem);
 403         return 0;
 404 }
 405
 406 static int xcopy_pt_write_pending(struct se_cmd *se_cmd)
 407 {
 408         return 0;
 409 }
 410
 411 static int xcopy_pt_write_pending_status(struct se_cmd *se_cmd)
 412 {
 413         return 0;
 414 }
 415
 416 static int xcopy_pt_queue_data_in(struct se_cmd *se_cmd)
 417 {
 418         return 0;
 419 }
 420
 421 static int xcopy_pt_queue_status(struct se_cmd *se_cmd)
 422 {
 423         return 0;
 424 }
 425
 426 static const struct target_core_fabric_ops xcopy_pt_tfo = {
 427         .get_fabric_name        = xcopy_pt_get_fabric_name,
 428         .get_cmd_state          = xcopy_pt_get_cmd_state,
 429         .release_cmd            = xcopy_pt_release_cmd,
 430         .check_stop_free        = xcopy_pt_check_stop_free,
 431         .write_pending          = xcopy_pt_write_pending,
 432         .write_pending_status   = xcopy_pt_write_pending_status,
 433         .queue_data_in          = xcopy_pt_queue_data_in,
 434         .queue_status           = xcopy_pt_queue_status,
 435 };
 436
 437 /*
 438  * End xcopy_pt_ops
 439  */
 440
 441 int target_xcopy_setup_pt(void)
 442 {
 443         xcopy_wq = alloc_workqueue("xcopy_wq", WQ_MEM_RECLAIM, 0);
 444         if (!xcopy_wq) {
 445                 pr_err("Unable to allocate xcopy_wq\n");
 446                 return -ENOMEM;
 447         }
 448
 449         memset(&xcopy_pt_tpg, 0, sizeof(struct se_portal_group));
 450         INIT_LIST_HEAD(&xcopy_pt_tpg.se_tpg_node);
 451         INIT_LIST_HEAD(&xcopy_pt_tpg.acl_node_list);
 452         INIT_LIST_HEAD(&xcopy_pt_tpg.tpg_sess_list);
 453
 454         xcopy_pt_tpg.se_tpg_tfo = &xcopy_pt_tfo;
 455
 456         memset(&xcopy_pt_nacl, 0, sizeof(struct se_node_acl));
 457         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_list);
 458         INIT_LIST_HEAD(&xcopy_pt_nacl.acl_sess_list);
 459         memset(&xcopy_pt_sess, 0, sizeof(struct se_session));
 460         INIT_LIST_HEAD(&xcopy_pt_sess.sess_list);
 461         INIT_LIST_HEAD(&xcopy_pt_sess.sess_acl_list);
 462         INIT_LIST_HEAD(&xcopy_pt_sess.sess_cmd_list);
 463         spin_lock_init(&xcopy_pt_sess.sess_cmd_lock);
 464
 465         xcopy_pt_nacl.se_tpg = &xcopy_pt_tpg;
 466         xcopy_pt_nacl.nacl_sess = &xcopy_pt_sess;
 467
 468         xcopy_pt_sess.se_tpg = &xcopy_pt_tpg;
 469         xcopy_pt_sess.se_node_acl = &xcopy_pt_nacl;
 470
 471         return 0;
 472 }
 473
 474 void target_xcopy_release_pt(void)
 475 {
 476         if (xcopy_wq)
 477                 destroy_workqueue(xcopy_wq);
 478 }
 479
 480 static void target_xcopy_setup_pt_port(
 481         struct xcopy_pt_cmd *xpt_cmd,
 482         struct xcopy_op *xop,
 483         bool remote_port)
 484 {
 485         struct se_cmd *ec_cmd = xop->xop_se_cmd;
 486         struct se_cmd *pt_cmd = &xpt_cmd->se_cmd;
 487
 488         if (xop->op_origin == XCOL_SOURCE_RECV_OP) {
 489                 /*
 490                  * Honor destination port reservations for X-COPY PUSH emulation
 491                  * when CDB is received on local source port, and READs blocks to
 492                  * WRITE on remote destination port.
 493                  */
 494                 if (remote_port) {
 495                         xpt_cmd->remote_port = remote_port;
 496                 } else {
 497                         pt_cmd->se_lun = ec_cmd->se_lun;
 498                         pt_cmd->se_dev = ec_cmd->se_dev;
 499
 500                         pr_debug("Honoring local SRC port from ec_cmd->se_dev:"
 501                                 " %p\n", pt_cmd->se_dev);
 502                         pt_cmd->se_lun = ec_cmd->se_lun;
 503                         pr_debug("Honoring local SRC port from ec_cmd->se_lun: %p\n",
 504                                 pt_cmd->se_lun);
 505                 }
 506         } else {
 507                 /*
 508                  * Honor source port reservation for X-COPY PULL emulation
 509                  * when CDB is received on local desintation port, and READs
 510                  * blocks from the remote source port to WRITE on local
 511                  * destination port.
 512                  */
 513                 if (remote_port) {
 514                         xpt_cmd->remote_port = remote_port;
 515                 } else {
 516                         pt_cmd->se_lun = ec_cmd->se_lun;
 517                         pt_cmd->se_dev = ec_cmd->se_dev;
 518
 519                         pr_debug("Honoring local DST port from ec_cmd->se_dev:"
 520                                 " %p\n", pt_cmd->se_dev);
 521                         pt_cmd->se_lun = ec_cmd->se_lun;
 522                         pr_debug("Honoring local DST port from ec_cmd->se_lun: %p\n",
 523                                 pt_cmd->se_lun);
 524                 }
 525         }
 526 }
 527
 528 static void target_xcopy_init_pt_lun(struct se_device *se_dev,
 529                 struct se_cmd *pt_cmd, bool remote_port)
 530 {
 531         /*
 532          * Don't allocate + init an pt_cmd->se_lun if honoring local port for
 533          * reservations.  The pt_cmd->se_lun pointer will be setup from within
 534          * target_xcopy_setup_pt_port()
 535          */
 536         if (remote_port) {
 537                 pr_debug("Setup emulated se_dev: %p from se_dev\n",
 538                         pt_cmd->se_dev);
 539                 pt_cmd->se_lun = &se_dev->xcopy_lun;
 540                 pt_cmd->se_dev = se_dev;
 541         }
 542
 543         pt_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
 544 }
 545
 546 static int target_xcopy_setup_pt_cmd(
 547         struct xcopy_pt_cmd *xpt_cmd,
 548         struct xcopy_op *xop,
 549         struct se_device *se_dev,
 550         unsigned char *cdb,
 551         bool remote_port,
 552         bool alloc_mem)
 553 {
 554         struct se_cmd *cmd = &xpt_cmd->se_cmd;
 555         sense_reason_t sense_rc;
 556         int ret = 0, rc;
 557         /*
 558          * Setup LUN+port to honor reservations based upon xop->op_origin for
 559          * X-COPY PUSH or X-COPY PULL based upon where the CDB was received.
 560          */
 561         target_xcopy_init_pt_lun(se_dev, cmd, remote_port);
 562
 563         xpt_cmd->xcopy_op = xop;
 564         target_xcopy_setup_pt_port(xpt_cmd, xop, remote_port);
 565
 566         cmd->tag = 0;
 567         sense_rc = target_setup_cmd_from_cdb(cmd, cdb);
 568         if (sense_rc) {
 569                 ret = -EINVAL;
 570                 goto out;
 571         }
 572
 573         if (alloc_mem) {
 574                 rc = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
 575                                       cmd->data_length, false);
 576                 if (rc < 0) {
 577                         ret = rc;
 578                         goto out;
 579                 }
 580                 /*
 581                  * Set this bit so that transport_free_pages() allows the
 582                  * caller to release SGLs + physical memory allocated by
 583                  * transport_generic_get_mem()..
 584                  */
 585                 cmd->se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
 586         } else {
 587                 /*
 588                  * Here the previously allocated SGLs for the internal READ
 589                  * are mapped zero-copy to the internal WRITE.
 590                  */
 591                 sense_rc = transport_generic_map_mem_to_cmd(cmd,
 592                                         xop->xop_data_sg, xop->xop_data_nents,
 593                                         NULL, 0);
 594                 if (sense_rc) {
 595                         ret = -EINVAL;
 596                         goto out;
 597                 }
 598
 599                 pr_debug("Setup PASSTHROUGH_NOALLOC t_data_sg: %p t_data_nents:"
 600                          " %u\n", cmd->t_data_sg, cmd->t_data_nents);
 601         }
 602
 603         return 0;
 604
 605 out:
 606         return ret;
 607 }
 608
 609 static int target_xcopy_issue_pt_cmd(struct xcopy_pt_cmd *xpt_cmd)
 610 {
 611         struct se_cmd *se_cmd = &xpt_cmd->se_cmd;
 612         sense_reason_t sense_rc;
 613
 614         sense_rc = transport_generic_new_cmd(se_cmd);
 615         if (sense_rc)
 616                 return -EINVAL;
 617
 618         if (se_cmd->data_direction == DMA_TO_DEVICE)
 619                 target_execute_cmd(se_cmd);
 620
 621         wait_for_completion_interruptible(&xpt_cmd->xpt_passthrough_sem);
 622
 623         pr_debug("target_xcopy_issue_pt_cmd(): SCSI status: 0x%02x\n",
 624                         se_cmd->scsi_status);
 625
 626         return (se_cmd->scsi_status) ? -EINVAL : 0;
 627 }
 628
 629 static int target_xcopy_read_source(
 630         struct se_cmd *ec_cmd,
 631         struct xcopy_op *xop,
 632         struct se_device *src_dev,
 633         sector_t src_lba,
 634         u32 src_sectors)
 635 {
 636         struct xcopy_pt_cmd *xpt_cmd;
 637         struct se_cmd *se_cmd;
 638         u32 length = (src_sectors * src_dev->dev_attrib.block_size);
 639         int rc;
 640         unsigned char cdb[16];
 641         bool remote_port = (xop->op_origin == XCOL_DEST_RECV_OP);
 642
 643         xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
 644         if (!xpt_cmd) {
 645                 pr_err("Unable to allocate xcopy_pt_cmd\n");
 646                 return -ENOMEM;
 647         }
 648         init_completion(&xpt_cmd->xpt_passthrough_sem);
 649         se_cmd = &xpt_cmd->se_cmd;
 650
 651         memset(&cdb[0], 0, 16);
 652         cdb[0] = READ_16;
 653         put_unaligned_be64(src_lba, &cdb[2]);
 654         put_unaligned_be32(src_sectors, &cdb[10]);
 655         pr_debug("XCOPY: Built READ_16: LBA: %llu Sectors: %u Length: %u\n",
 656                 (unsigned long long)src_lba, src_sectors, length);
 657
 658         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 659                               DMA_FROM_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
 660         xop->src_pt_cmd = xpt_cmd;
 661
 662         rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, src_dev, &cdb[0],
 663                                 remote_port, true);
 664         if (rc < 0) {
 665                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
 666                 transport_generic_free_cmd(se_cmd, 0);
 667                 return rc;
 668         }
 669
 670         xop->xop_data_sg = se_cmd->t_data_sg;
 671         xop->xop_data_nents = se_cmd->t_data_nents;
 672         pr_debug("XCOPY-READ: Saved xop->xop_data_sg: %p, num: %u for READ"
 673                 " memory\n", xop->xop_data_sg, xop->xop_data_nents);
 674
 675         rc = target_xcopy_issue_pt_cmd(xpt_cmd);
 676         if (rc < 0) {
 677                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
 678                 transport_generic_free_cmd(se_cmd, 0);
 679                 return rc;
 680         }
 681         /*
 682          * Clear off the allocated t_data_sg, that has been saved for
 683          * zero-copy WRITE submission reuse in struct xcopy_op..
 684          */
 685         se_cmd->t_data_sg = NULL;
 686         se_cmd->t_data_nents = 0;
 687
 688         return 0;
 689 }
 690
 691 static int target_xcopy_write_destination(
 692         struct se_cmd *ec_cmd,
 693         struct xcopy_op *xop,
 694         struct se_device *dst_dev,
 695         sector_t dst_lba,
 696         u32 dst_sectors)
 697 {
 698         struct xcopy_pt_cmd *xpt_cmd;
 699         struct se_cmd *se_cmd;
 700         u32 length = (dst_sectors * dst_dev->dev_attrib.block_size);
 701         int rc;
 702         unsigned char cdb[16];
 703         bool remote_port = (xop->op_origin == XCOL_SOURCE_RECV_OP);
 704
 705         xpt_cmd = kzalloc(sizeof(struct xcopy_pt_cmd), GFP_KERNEL);
 706         if (!xpt_cmd) {
 707                 pr_err("Unable to allocate xcopy_pt_cmd\n");
 708                 return -ENOMEM;
 709         }
 710         init_completion(&xpt_cmd->xpt_passthrough_sem);
 711         se_cmd = &xpt_cmd->se_cmd;
 712
 713         memset(&cdb[0], 0, 16);
 714         cdb[0] = WRITE_16;
 715         put_unaligned_be64(dst_lba, &cdb[2]);
 716         put_unaligned_be32(dst_sectors, &cdb[10]);
 717         pr_debug("XCOPY: Built WRITE_16: LBA: %llu Sectors: %u Length: %u\n",
 718                 (unsigned long long)dst_lba, dst_sectors, length);
 719
 720         transport_init_se_cmd(se_cmd, &xcopy_pt_tfo, &xcopy_pt_sess, length,
 721                               DMA_TO_DEVICE, 0, &xpt_cmd->sense_buffer[0]);
 722         xop->dst_pt_cmd = xpt_cmd;
 723
 724         rc = target_xcopy_setup_pt_cmd(xpt_cmd, xop, dst_dev, &cdb[0],
 725                                 remote_port, false);
 726         if (rc < 0) {
 727                 struct se_cmd *src_cmd = &xop->src_pt_cmd->se_cmd;
 728                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
 729                 /*
 730                  * If the failure happened before the t_mem_list hand-off in
 731                  * target_xcopy_setup_pt_cmd(), Reset memory + clear flag so that
 732                  * core releases this memory on error during X-COPY WRITE I/O.
 733                  */
 734                 src_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
 735                 src_cmd->t_data_sg = xop->xop_data_sg;
 736                 src_cmd->t_data_nents = xop->xop_data_nents;
 737
 738                 transport_generic_free_cmd(se_cmd, 0);
 739                 return rc;
 740         }
 741
 742         rc = target_xcopy_issue_pt_cmd(xpt_cmd);
 743         if (rc < 0) {
 744                 ec_cmd->scsi_status = xpt_cmd->se_cmd.scsi_status;
 745                 se_cmd->se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
 746                 transport_generic_free_cmd(se_cmd, 0);
 747                 return rc;
 748         }
 749
 750         return 0;
 751 }
 752
 753 static void target_xcopy_do_work(struct work_struct *work)
 754 {
 755         struct xcopy_op *xop = container_of(work, struct xcopy_op, xop_work);
 756         struct se_device *src_dev = xop->src_dev, *dst_dev = xop->dst_dev;
 757         struct se_cmd *ec_cmd = xop->xop_se_cmd;
 758         sector_t src_lba = xop->src_lba, dst_lba = xop->dst_lba, end_lba;
 759         unsigned int max_sectors;
 760         int rc;
 761         unsigned short nolb = xop->nolb, cur_nolb, max_nolb, copied_nolb = 0;
 762
 763         end_lba = src_lba + nolb;
 764         /*
 765          * Break up XCOPY I/O into hw_max_sectors sized I/O based on the
 766          * smallest max_sectors between src_dev + dev_dev, or
 767          */
 768         max_sectors = min(src_dev->dev_attrib.hw_max_sectors,
 769                           dst_dev->dev_attrib.hw_max_sectors);
 770         max_sectors = min_t(u32, max_sectors, XCOPY_MAX_SECTORS);
 771
 772         max_nolb = min_t(u16, max_sectors, ((u16)(~0U)));
 773
 774         pr_debug("target_xcopy_do_work: nolb: %hu, max_nolb: %hu end_lba: %llu\n",
 775                         nolb, max_nolb, (unsigned long long)end_lba);
 776         pr_debug("target_xcopy_do_work: Starting src_lba: %llu, dst_lba: %llu\n",
 777                         (unsigned long long)src_lba, (unsigned long long)dst_lba);
 778
 779         while (src_lba < end_lba) {
 780                 cur_nolb = min(nolb, max_nolb);
 781
 782                 pr_debug("target_xcopy_do_work: Calling read src_dev: %p src_lba: %llu,"
 783                         " cur_nolb: %hu\n", src_dev, (unsigned long long)src_lba, cur_nolb);
 784
 785                 rc = target_xcopy_read_source(ec_cmd, xop, src_dev, src_lba, cur_nolb);
 786                 if (rc < 0)
 787                         goto out;
 788
 789                 src_lba += cur_nolb;
 790                 pr_debug("target_xcopy_do_work: Incremented READ src_lba to %llu\n",
 791                                 (unsigned long long)src_lba);
 792
 793                 pr_debug("target_xcopy_do_work: Calling write dst_dev: %p dst_lba: %llu,"
 794                         " cur_nolb: %hu\n", dst_dev, (unsigned long long)dst_lba, cur_nolb);
 795
 796                 rc = target_xcopy_write_destination(ec_cmd, xop, dst_dev,
 797                                                 dst_lba, cur_nolb);
 798                 if (rc < 0) {
 799                         transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
 800                         goto out;
 801                 }
 802
 803                 dst_lba += cur_nolb;
 804                 pr_debug("target_xcopy_do_work: Incremented WRITE dst_lba to %llu\n",
 805                                 (unsigned long long)dst_lba);
 806
 807                 copied_nolb += cur_nolb;
 808                 nolb -= cur_nolb;
 809
 810                 transport_generic_free_cmd(&xop->src_pt_cmd->se_cmd, 0);
 811                 xop->dst_pt_cmd->se_cmd.se_cmd_flags &= ~SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
 812
 813                 transport_generic_free_cmd(&xop->dst_pt_cmd->se_cmd, 0);
 814         }
 815
 816         xcopy_pt_undepend_remotedev(xop);
 817         kfree(xop);
 818
 819         pr_debug("target_xcopy_do_work: Final src_lba: %llu, dst_lba: %llu\n",
 820                 (unsigned long long)src_lba, (unsigned long long)dst_lba);
 821         pr_debug("target_xcopy_do_work: Blocks copied: %hu, Bytes Copied: %u\n",
 822                 copied_nolb, copied_nolb * dst_dev->dev_attrib.block_size);
 823
 824         pr_debug("target_xcopy_do_work: Setting X-COPY GOOD status -> sending response\n");
 825         target_complete_cmd(ec_cmd, SAM_STAT_GOOD);
 826         return;
 827
 828 out:
 829         xcopy_pt_undepend_remotedev(xop);
 830         kfree(xop);
 831         /*
 832          * Don't override an error scsi status if it has already been set
 833          */
 834         if (ec_cmd->scsi_status == SAM_STAT_GOOD) {
 835                 pr_warn_ratelimited("target_xcopy_do_work: rc: %d, Setting X-COPY"
 836                         " CHECK_CONDITION -> sending response\n", rc);
 837                 ec_cmd->scsi_status = SAM_STAT_CHECK_CONDITION;
 838         }
 839         target_complete_cmd(ec_cmd, ec_cmd->scsi_status);
 840 }
 841
 842 sense_reason_t target_do_xcopy(struct se_cmd *se_cmd)
 843 {
 844         struct se_device *dev = se_cmd->se_dev;
 845         struct xcopy_op *xop = NULL;
 846         unsigned char *p = NULL, *seg_desc;
 847         unsigned int list_id, list_id_usage, sdll, inline_dl, sa;
 848         sense_reason_t ret = TCM_INVALID_PARAMETER_LIST;
 849         int rc;
 850         unsigned short tdll;
 851
 852         if (!dev->dev_attrib.emulate_3pc) {
 853                 pr_err("EXTENDED_COPY operation explicitly disabled\n");
 854                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 855         }
 856
 857         sa = se_cmd->t_task_cdb[1] & 0x1f;
 858         if (sa != 0x00) {
 859                 pr_err("EXTENDED_COPY(LID4) not supported\n");
 860                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 861         }
 862
 863         xop = kzalloc(sizeof(struct xcopy_op), GFP_KERNEL);
 864         if (!xop) {
 865                 pr_err("Unable to allocate xcopy_op\n");
 866                 return TCM_OUT_OF_RESOURCES;
 867         }
 868         xop->xop_se_cmd = se_cmd;
 869
 870         p = transport_kmap_data_sg(se_cmd);
 871         if (!p) {
 872                 pr_err("transport_kmap_data_sg() failed in target_do_xcopy\n");
 873                 kfree(xop);
 874                 return TCM_OUT_OF_RESOURCES;
 875         }
 876
 877         list_id = p[0];
 878         list_id_usage = (p[1] & 0x18) >> 3;
 879
 880         /*
 881          * Determine TARGET DESCRIPTOR LIST LENGTH + SEGMENT DESCRIPTOR LIST LENGTH
 882          */
 883         tdll = get_unaligned_be16(&p[2]);
 884         sdll = get_unaligned_be32(&p[8]);
 885
 886         inline_dl = get_unaligned_be32(&p[12]);
 887         if (inline_dl != 0) {
 888                 pr_err("XCOPY with non zero inline data length\n");
 889                 goto out;
 890         }
 891
 892         pr_debug("Processing XCOPY with list_id: 0x%02x list_id_usage: 0x%02x"
 893                 " tdll: %hu sdll: %u inline_dl: %u\n", list_id, list_id_usage,
 894                 tdll, sdll, inline_dl);
 895
 896         rc = target_xcopy_parse_target_descriptors(se_cmd, xop, &p[16], tdll, &ret);
 897         if (rc <= 0)
 898                 goto out;
 899
 900         if (xop->src_dev->dev_attrib.block_size !=
 901             xop->dst_dev->dev_attrib.block_size) {
 902                 pr_err("XCOPY: Non matching src_dev block_size: %u + dst_dev"
 903                        " block_size: %u currently unsupported\n",
 904                         xop->src_dev->dev_attrib.block_size,
 905                         xop->dst_dev->dev_attrib.block_size);
 906                 xcopy_pt_undepend_remotedev(xop);
 907                 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 908                 goto out;
 909         }
 910
 911         pr_debug("XCOPY: Processed %d target descriptors, length: %u\n", rc,
 912                                 rc * XCOPY_TARGET_DESC_LEN);
 913         seg_desc = &p[16];
 914         seg_desc += (rc * XCOPY_TARGET_DESC_LEN);
 915
 916         rc = target_xcopy_parse_segment_descriptors(se_cmd, xop, seg_desc, sdll);
 917         if (rc <= 0) {
 918                 xcopy_pt_undepend_remotedev(xop);
 919                 goto out;
 920         }
 921         transport_kunmap_data_sg(se_cmd);
 922
 923         pr_debug("XCOPY: Processed %d segment descriptors, length: %u\n", rc,
 924                                 rc * XCOPY_SEGMENT_DESC_LEN);
 925         INIT_WORK(&xop->xop_work, target_xcopy_do_work);
 926         queue_work(xcopy_wq, &xop->xop_work);
 927         return TCM_NO_SENSE;
 928
 929 out:
 930         if (p)
 931                 transport_kunmap_data_sg(se_cmd);
 932         kfree(xop);
 933         return ret;
 934 }
 935
 936 static sense_reason_t target_rcr_operating_parameters(struct se_cmd *se_cmd)
 937 {
 938         unsigned char *p;
 939
 940         p = transport_kmap_data_sg(se_cmd);
 941         if (!p) {
 942                 pr_err("transport_kmap_data_sg failed in"
 943                        " target_rcr_operating_parameters\n");
 944                 return TCM_OUT_OF_RESOURCES;
 945         }
 946
 947         if (se_cmd->data_length < 54) {
 948                 pr_err("Receive Copy Results Op Parameters length"
 949                        " too small: %u\n", se_cmd->data_length);
 950                 transport_kunmap_data_sg(se_cmd);
 951                 return TCM_INVALID_CDB_FIELD;
 952         }
 953         /*
 954          * Set SNLID=1 (Supports no List ID)
 955          */
 956         p[4] = 0x1;
 957         /*
 958          * MAXIMUM TARGET DESCRIPTOR COUNT
 959          */
 960         put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &p[8]);
 961         /*
 962          * MAXIMUM SEGMENT DESCRIPTOR COUNT
 963          */
 964         put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &p[10]);
 965         /*
 966          * MAXIMUM DESCRIPTOR LIST LENGTH
 967          */
 968         put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &p[12]);
 969         /*
 970          * MAXIMUM SEGMENT LENGTH
 971          */
 972         put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &p[16]);
 973         /*
 974          * MAXIMUM INLINE DATA LENGTH for SA 0x04 (NOT SUPPORTED)
 975          */
 976         put_unaligned_be32(0x0, &p[20]);
 977         /*
 978          * HELD DATA LIMIT
 979          */
 980         put_unaligned_be32(0x0, &p[24]);
 981         /*
 982          * MAXIMUM STREAM DEVICE TRANSFER SIZE
 983          */
 984         put_unaligned_be32(0x0, &p[28]);
 985         /*
 986          * TOTAL CONCURRENT COPIES
 987          */
 988         put_unaligned_be16(RCR_OP_TOTAL_CONCURR_COPIES, &p[34]);
 989         /*
 990          * MAXIMUM CONCURRENT COPIES
 991          */
 992         p[36] = RCR_OP_MAX_CONCURR_COPIES;
 993         /*
 994          * DATA SEGMENT GRANULARITY (log 2)
 995          */
 996         p[37] = RCR_OP_DATA_SEG_GRAN_LOG2;
 997         /*
 998          * INLINE DATA GRANULARITY log 2)
 999          */
1000         p[38] = RCR_OP_INLINE_DATA_GRAN_LOG2;
1001         /*
1002          * HELD DATA GRANULARITY
1003          */
1004         p[39] = RCR_OP_HELD_DATA_GRAN_LOG2;
1005         /*
1006          * IMPLEMENTED DESCRIPTOR LIST LENGTH
1007          */
1008         p[43] = 0x2;
1009         /*
1010          * List of implemented descriptor type codes (ordered)
1011          */
1012         p[44] = 0x02; /* Copy Block to Block device */
1013         p[45] = 0xe4; /* Identification descriptor target descriptor */
1014
1015         /*
1016          * AVAILABLE DATA (n-3)
1017          */
1018         put_unaligned_be32(42, &p[0]);
1019
1020         transport_kunmap_data_sg(se_cmd);
1021         target_complete_cmd(se_cmd, GOOD);
1022
1023         return TCM_NO_SENSE;
1024 }
1025
1026 sense_reason_t target_do_receive_copy_results(struct se_cmd *se_cmd)
1027 {
1028         unsigned char *cdb = &se_cmd->t_task_cdb[0];
1029         int sa = (cdb[1] & 0x1f), list_id = cdb[2];
1030         sense_reason_t rc = TCM_NO_SENSE;
1031
1032         pr_debug("Entering target_do_receive_copy_results: SA: 0x%02x, List ID:"
1033                 " 0x%02x, AL: %u\n", sa, list_id, se_cmd->data_length);
1034
1035         if (list_id != 0) {
1036                 pr_err("Receive Copy Results with non zero list identifier"
1037                        " not supported\n");
1038                 return TCM_INVALID_CDB_FIELD;
1039         }
1040
1041         switch (sa) {
1042         case RCR_SA_OPERATING_PARAMETERS:
1043                 rc = target_rcr_operating_parameters(se_cmd);
1044                 break;
1045         case RCR_SA_COPY_STATUS:
1046         case RCR_SA_RECEIVE_DATA:
1047         case RCR_SA_FAILED_SEGMENT_DETAILS:
1048         default:
1049                 pr_err("Unsupported SA for receive copy results: 0x%02x\n", sa);
1050                 return TCM_INVALID_CDB_FIELD;
1051         }
1052
1053         return rc;
1054 }