drivers/target/target_core_rd.c

   1 /*******************************************************************************
   2  * Filename:  target_core_rd.c
   3  *
   4  * This file contains the Storage Engine <-> Ramdisk transport
   5  * specific functions.
   6  *
   7  * (c) Copyright 2003-2013 Datera, Inc.
   8  *
   9  * Nicholas A. Bellinger <nab@kernel.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  24  *
  25  ******************************************************************************/
  26
  27 #include <linux/string.h>
  28 #include <linux/parser.h>
  29 #include <linux/timer.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <scsi/scsi.h>
  33 #include <scsi/scsi_host.h>
  34
  35 #include <target/target_core_base.h>
  36 #include <target/target_core_backend.h>
  37
  38 #include "target_core_rd.h"
  39
  40 static inline struct rd_dev *RD_DEV(struct se_device *dev)
  41 {
  42         return container_of(dev, struct rd_dev, dev);
  43 }
  44
  45 /*      rd_attach_hba(): (Part of se_subsystem_api_t template)
  46  *
  47  *
  48  */
  49 static int rd_attach_hba(struct se_hba *hba, u32 host_id)
  50 {
  51         struct rd_host *rd_host;
  52
  53         rd_host = kzalloc(sizeof(struct rd_host), GFP_KERNEL);
  54         if (!rd_host) {
  55                 pr_err("Unable to allocate memory for struct rd_host\n");
  56                 return -ENOMEM;
  57         }
  58
  59         rd_host->rd_host_id = host_id;
  60
  61         hba->hba_ptr = rd_host;
  62
  63         pr_debug("CORE_HBA[%d] - TCM Ramdisk HBA Driver %s on"
  64                 " Generic Target Core Stack %s\n", hba->hba_id,
  65                 RD_HBA_VERSION, TARGET_CORE_MOD_VERSION);
  66
  67         return 0;
  68 }
  69
  70 static void rd_detach_hba(struct se_hba *hba)
  71 {
  72         struct rd_host *rd_host = hba->hba_ptr;
  73
  74         pr_debug("CORE_HBA[%d] - Detached Ramdisk HBA: %u from"
  75                 " Generic Target Core\n", hba->hba_id, rd_host->rd_host_id);
  76
  77         kfree(rd_host);
  78         hba->hba_ptr = NULL;
  79 }
  80
  81 static u32 rd_release_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
  82                                  u32 sg_table_count)
  83 {
  84         struct page *pg;
  85         struct scatterlist *sg;
  86         u32 i, j, page_count = 0, sg_per_table;
  87
  88         for (i = 0; i < sg_table_count; i++) {
  89                 sg = sg_table[i].sg_table;
  90                 sg_per_table = sg_table[i].rd_sg_count;
  91
  92                 for (j = 0; j < sg_per_table; j++) {
  93                         pg = sg_page(&sg[j]);
  94                         if (pg) {
  95                                 __free_page(pg);
  96                                 page_count++;
  97                         }
  98                 }
  99                 kfree(sg);
 100         }
 101
 102         kfree(sg_table);
 103         return page_count;
 104 }
 105
 106 static void rd_release_device_space(struct rd_dev *rd_dev)
 107 {
 108         u32 page_count;
 109
 110         if (!rd_dev->sg_table_array || !rd_dev->sg_table_count)
 111                 return;
 112
 113         page_count = rd_release_sgl_table(rd_dev, rd_dev->sg_table_array,
 114                                           rd_dev->sg_table_count);
 115
 116         pr_debug("CORE_RD[%u] - Released device space for Ramdisk"
 117                 " Device ID: %u, pages %u in %u tables total bytes %lu\n",
 118                 rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
 119                 rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
 120
 121         rd_dev->sg_table_array = NULL;
 122         rd_dev->sg_table_count = 0;
 123 }
 124
 125
 126 /*      rd_build_device_space():
 127  *
 128  *
 129  */
 130 static int rd_allocate_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
 131                                  u32 total_sg_needed, unsigned char init_payload)
 132 {
 133         u32 i = 0, j, page_offset = 0, sg_per_table;
 134         u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
 135                                 sizeof(struct scatterlist));
 136         struct page *pg;
 137         struct scatterlist *sg;
 138         unsigned char *p;
 139
 140         while (total_sg_needed) {
 141                 sg_per_table = (total_sg_needed > max_sg_per_table) ?
 142                         max_sg_per_table : total_sg_needed;
 143
 144                 sg = kzalloc(sg_per_table * sizeof(struct scatterlist),
 145                                 GFP_KERNEL);
 146                 if (!sg) {
 147                         pr_err("Unable to allocate scatterlist array"
 148                                 " for struct rd_dev\n");
 149                         return -ENOMEM;
 150                 }
 151
 152                 sg_init_table(sg, sg_per_table);
 153
 154                 sg_table[i].sg_table = sg;
 155                 sg_table[i].rd_sg_count = sg_per_table;
 156                 sg_table[i].page_start_offset = page_offset;
 157                 sg_table[i++].page_end_offset = (page_offset + sg_per_table)
 158                                                 - 1;
 159
 160                 for (j = 0; j < sg_per_table; j++) {
 161                         pg = alloc_pages(GFP_KERNEL, 0);
 162                         if (!pg) {
 163                                 pr_err("Unable to allocate scatterlist"
 164                                         " pages for struct rd_dev_sg_table\n");
 165                                 return -ENOMEM;
 166                         }
 167                         sg_assign_page(&sg[j], pg);
 168                         sg[j].length = PAGE_SIZE;
 169
 170                         p = kmap(pg);
 171                         memset(p, init_payload, PAGE_SIZE);
 172                         kunmap(pg);
 173                 }
 174
 175                 page_offset += sg_per_table;
 176                 total_sg_needed -= sg_per_table;
 177         }
 178
 179         return 0;
 180 }
 181
 182 static int rd_build_device_space(struct rd_dev *rd_dev)
 183 {
 184         struct rd_dev_sg_table *sg_table;
 185         u32 sg_tables, total_sg_needed;
 186         u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
 187                                 sizeof(struct scatterlist));
 188         int rc;
 189
 190         if (rd_dev->rd_page_count <= 0) {
 191                 pr_err("Illegal page count: %u for Ramdisk device\n",
 192                        rd_dev->rd_page_count);
 193                 return -EINVAL;
 194         }
 195
 196         /* Don't need backing pages for NULLIO */
 197         if (rd_dev->rd_flags & RDF_NULLIO)
 198                 return 0;
 199
 200         total_sg_needed = rd_dev->rd_page_count;
 201
 202         sg_tables = (total_sg_needed / max_sg_per_table) + 1;
 203
 204         sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
 205         if (!sg_table) {
 206                 pr_err("Unable to allocate memory for Ramdisk"
 207                        " scatterlist tables\n");
 208                 return -ENOMEM;
 209         }
 210
 211         rd_dev->sg_table_array = sg_table;
 212         rd_dev->sg_table_count = sg_tables;
 213
 214         rc = rd_allocate_sgl_table(rd_dev, sg_table, total_sg_needed, 0x00);
 215         if (rc)
 216                 return rc;
 217
 218         pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u space of"
 219                  " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
 220                  rd_dev->rd_dev_id, rd_dev->rd_page_count,
 221                  rd_dev->sg_table_count);
 222
 223         return 0;
 224 }
 225
 226 static void rd_release_prot_space(struct rd_dev *rd_dev)
 227 {
 228         u32 page_count;
 229
 230         if (!rd_dev->sg_prot_array || !rd_dev->sg_prot_count)
 231                 return;
 232
 233         page_count = rd_release_sgl_table(rd_dev, rd_dev->sg_prot_array,
 234                                           rd_dev->sg_prot_count);
 235
 236         pr_debug("CORE_RD[%u] - Released protection space for Ramdisk"
 237                  " Device ID: %u, pages %u in %u tables total bytes %lu\n",
 238                  rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
 239                  rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
 240
 241         rd_dev->sg_prot_array = NULL;
 242         rd_dev->sg_prot_count = 0;
 243 }
 244
 245 static int rd_build_prot_space(struct rd_dev *rd_dev, int prot_length, int block_size)
 246 {
 247         struct rd_dev_sg_table *sg_table;
 248         u32 total_sg_needed, sg_tables;
 249         u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
 250                                 sizeof(struct scatterlist));
 251         int rc;
 252
 253         if (rd_dev->rd_flags & RDF_NULLIO)
 254                 return 0;
 255         /*
 256          * prot_length=8byte dif data
 257          * tot sg needed = rd_page_count * (PGSZ/block_size) *
 258          *                 (prot_length/block_size) + pad
 259          * PGSZ canceled each other.
 260          */
 261         total_sg_needed = (rd_dev->rd_page_count * prot_length / block_size) + 1;
 262
 263         sg_tables = (total_sg_needed / max_sg_per_table) + 1;
 264
 265         sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
 266         if (!sg_table) {
 267                 pr_err("Unable to allocate memory for Ramdisk protection"
 268                        " scatterlist tables\n");
 269                 return -ENOMEM;
 270         }
 271
 272         rd_dev->sg_prot_array = sg_table;
 273         rd_dev->sg_prot_count = sg_tables;
 274
 275         rc = rd_allocate_sgl_table(rd_dev, sg_table, total_sg_needed, 0xff);
 276         if (rc)
 277                 return rc;
 278
 279         pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u prot space of"
 280                  " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
 281                  rd_dev->rd_dev_id, total_sg_needed, rd_dev->sg_prot_count);
 282
 283         return 0;
 284 }
 285
 286 static struct se_device *rd_alloc_device(struct se_hba *hba, const char *name)
 287 {
 288         struct rd_dev *rd_dev;
 289         struct rd_host *rd_host = hba->hba_ptr;
 290
 291         rd_dev = kzalloc(sizeof(struct rd_dev), GFP_KERNEL);
 292         if (!rd_dev) {
 293                 pr_err("Unable to allocate memory for struct rd_dev\n");
 294                 return NULL;
 295         }
 296
 297         rd_dev->rd_host = rd_host;
 298
 299         return &rd_dev->dev;
 300 }
 301
 302 static int rd_configure_device(struct se_device *dev)
 303 {
 304         struct rd_dev *rd_dev = RD_DEV(dev);
 305         struct rd_host *rd_host = dev->se_hba->hba_ptr;
 306         int ret;
 307
 308         if (!(rd_dev->rd_flags & RDF_HAS_PAGE_COUNT)) {
 309                 pr_debug("Missing rd_pages= parameter\n");
 310                 return -EINVAL;
 311         }
 312
 313         ret = rd_build_device_space(rd_dev);
 314         if (ret < 0)
 315                 goto fail;
 316
 317         dev->dev_attrib.hw_block_size = RD_BLOCKSIZE;
 318         dev->dev_attrib.hw_max_sectors = UINT_MAX;
 319         dev->dev_attrib.hw_queue_depth = RD_MAX_DEVICE_QUEUE_DEPTH;
 320
 321         rd_dev->rd_dev_id = rd_host->rd_host_dev_id_count++;
 322
 323         pr_debug("CORE_RD[%u] - Added TCM MEMCPY Ramdisk Device ID: %u of"
 324                 " %u pages in %u tables, %lu total bytes\n",
 325                 rd_host->rd_host_id, rd_dev->rd_dev_id, rd_dev->rd_page_count,
 326                 rd_dev->sg_table_count,
 327                 (unsigned long)(rd_dev->rd_page_count * PAGE_SIZE));
 328
 329         return 0;
 330
 331 fail:
 332         rd_release_device_space(rd_dev);
 333         return ret;
 334 }
 335
 336 static void rd_free_device(struct se_device *dev)
 337 {
 338         struct rd_dev *rd_dev = RD_DEV(dev);
 339
 340         rd_release_device_space(rd_dev);
 341         kfree(rd_dev);
 342 }
 343
 344 static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page)
 345 {
 346         struct rd_dev_sg_table *sg_table;
 347         u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE /
 348                                 sizeof(struct scatterlist));
 349
 350         i = page / sg_per_table;
 351         if (i < rd_dev->sg_table_count) {
 352                 sg_table = &rd_dev->sg_table_array[i];
 353                 if ((sg_table->page_start_offset <= page) &&
 354                     (sg_table->page_end_offset >= page))
 355                         return sg_table;
 356         }
 357
 358         pr_err("Unable to locate struct rd_dev_sg_table for page: %u\n",
 359                         page);
 360
 361         return NULL;
 362 }
 363
 364 static struct rd_dev_sg_table *rd_get_prot_table(struct rd_dev *rd_dev, u32 page)
 365 {
 366         struct rd_dev_sg_table *sg_table;
 367         u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE /
 368                                 sizeof(struct scatterlist));
 369
 370         i = page / sg_per_table;
 371         if (i < rd_dev->sg_prot_count) {
 372                 sg_table = &rd_dev->sg_prot_array[i];
 373                 if ((sg_table->page_start_offset <= page) &&
 374                      (sg_table->page_end_offset >= page))
 375                         return sg_table;
 376         }
 377
 378         pr_err("Unable to locate struct prot rd_dev_sg_table for page: %u\n",
 379                         page);
 380
 381         return NULL;
 382 }
 383
 384 static sense_reason_t
 385 rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 386               enum dma_data_direction data_direction)
 387 {
 388         struct se_device *se_dev = cmd->se_dev;
 389         struct rd_dev *dev = RD_DEV(se_dev);
 390         struct rd_dev_sg_table *table;
 391         struct scatterlist *rd_sg;
 392         struct sg_mapping_iter m;
 393         u32 rd_offset;
 394         u32 rd_size;
 395         u32 rd_page;
 396         u32 src_len;
 397         u64 tmp;
 398         sense_reason_t rc;
 399
 400         if (dev->rd_flags & RDF_NULLIO) {
 401                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 402                 return 0;
 403         }
 404
 405         tmp = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 406         rd_offset = do_div(tmp, PAGE_SIZE);
 407         rd_page = tmp;
 408         rd_size = cmd->data_length;
 409
 410         table = rd_get_sg_table(dev, rd_page);
 411         if (!table)
 412                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 413
 414         rd_sg = &table->sg_table[rd_page - table->page_start_offset];
 415
 416         pr_debug("RD[%u]: %s LBA: %llu, Size: %u Page: %u, Offset: %u\n",
 417                         dev->rd_dev_id,
 418                         data_direction == DMA_FROM_DEVICE ? "Read" : "Write",
 419                         cmd->t_task_lba, rd_size, rd_page, rd_offset);
 420
 421         if (cmd->prot_type && data_direction == DMA_TO_DEVICE) {
 422                 struct rd_dev_sg_table *prot_table;
 423                 struct scatterlist *prot_sg;
 424                 u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
 425                 u32 prot_offset, prot_page;
 426
 427                 tmp = cmd->t_task_lba * se_dev->prot_length;
 428                 prot_offset = do_div(tmp, PAGE_SIZE);
 429                 prot_page = tmp;
 430
 431                 prot_table = rd_get_prot_table(dev, prot_page);
 432                 if (!prot_table)
 433                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 434
 435                 prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset];
 436
 437                 rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors, 0,
 438                                           prot_sg, prot_offset);
 439                 if (rc)
 440                         return rc;
 441         }
 442
 443         src_len = PAGE_SIZE - rd_offset;
 444         sg_miter_start(&m, sgl, sgl_nents,
 445                         data_direction == DMA_FROM_DEVICE ?
 446                                 SG_MITER_TO_SG : SG_MITER_FROM_SG);
 447         while (rd_size) {
 448                 u32 len;
 449                 void *rd_addr;
 450
 451                 sg_miter_next(&m);
 452                 if (!(u32)m.length) {
 453                         pr_debug("RD[%u]: invalid sgl %p len %zu\n",
 454                                  dev->rd_dev_id, m.addr, m.length);
 455                         sg_miter_stop(&m);
 456                         return TCM_INCORRECT_AMOUNT_OF_DATA;
 457                 }
 458                 len = min((u32)m.length, src_len);
 459                 if (len > rd_size) {
 460                         pr_debug("RD[%u]: size underrun page %d offset %d "
 461                                  "size %d\n", dev->rd_dev_id,
 462                                  rd_page, rd_offset, rd_size);
 463                         len = rd_size;
 464                 }
 465                 m.consumed = len;
 466
 467                 rd_addr = sg_virt(rd_sg) + rd_offset;
 468
 469                 if (data_direction == DMA_FROM_DEVICE)
 470                         memcpy(m.addr, rd_addr, len);
 471                 else
 472                         memcpy(rd_addr, m.addr, len);
 473
 474                 rd_size -= len;
 475                 if (!rd_size)
 476                         continue;
 477
 478                 src_len -= len;
 479                 if (src_len) {
 480                         rd_offset += len;
 481                         continue;
 482                 }
 483
 484                 /* rd page completed, next one please */
 485                 rd_page++;
 486                 rd_offset = 0;
 487                 src_len = PAGE_SIZE;
 488                 if (rd_page <= table->page_end_offset) {
 489                         rd_sg++;
 490                         continue;
 491                 }
 492
 493                 table = rd_get_sg_table(dev, rd_page);
 494                 if (!table) {
 495                         sg_miter_stop(&m);
 496                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 497                 }
 498
 499                 /* since we increment, the first sg entry is correct */
 500                 rd_sg = table->sg_table;
 501         }
 502         sg_miter_stop(&m);
 503
 504         if (cmd->prot_type && data_direction == DMA_FROM_DEVICE) {
 505                 struct rd_dev_sg_table *prot_table;
 506                 struct scatterlist *prot_sg;
 507                 u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
 508                 u32 prot_offset, prot_page;
 509
 510                 tmp = cmd->t_task_lba * se_dev->prot_length;
 511                 prot_offset = do_div(tmp, PAGE_SIZE);
 512                 prot_page = tmp;
 513
 514                 prot_table = rd_get_prot_table(dev, prot_page);
 515                 if (!prot_table)
 516                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 517
 518                 prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset];
 519
 520                 rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0,
 521                                          prot_sg, prot_offset);
 522                 if (rc)
 523                         return rc;
 524         }
 525
 526         target_complete_cmd(cmd, SAM_STAT_GOOD);
 527         return 0;
 528 }
 529
 530 enum {
 531         Opt_rd_pages, Opt_rd_nullio, Opt_err
 532 };
 533
 534 static match_table_t tokens = {
 535         {Opt_rd_pages, "rd_pages=%d"},
 536         {Opt_rd_nullio, "rd_nullio=%d"},
 537         {Opt_err, NULL}
 538 };
 539
 540 static ssize_t rd_set_configfs_dev_params(struct se_device *dev,
 541                 const char *page, ssize_t count)
 542 {
 543         struct rd_dev *rd_dev = RD_DEV(dev);
 544         char *orig, *ptr, *opts;
 545         substring_t args[MAX_OPT_ARGS];
 546         int ret = 0, arg, token;
 547
 548         opts = kstrdup(page, GFP_KERNEL);
 549         if (!opts)
 550                 return -ENOMEM;
 551
 552         orig = opts;
 553
 554         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 555                 if (!*ptr)
 556                         continue;
 557
 558                 token = match_token(ptr, tokens, args);
 559                 switch (token) {
 560                 case Opt_rd_pages:
 561                         match_int(args, &arg);
 562                         rd_dev->rd_page_count = arg;
 563                         pr_debug("RAMDISK: Referencing Page"
 564                                 " Count: %u\n", rd_dev->rd_page_count);
 565                         rd_dev->rd_flags |= RDF_HAS_PAGE_COUNT;
 566                         break;
 567                 case Opt_rd_nullio:
 568                         match_int(args, &arg);
 569                         if (arg != 1)
 570                                 break;
 571
 572                         pr_debug("RAMDISK: Setting NULLIO flag: %d\n", arg);
 573                         rd_dev->rd_flags |= RDF_NULLIO;
 574                         break;
 575                 default:
 576                         break;
 577                 }
 578         }
 579
 580         kfree(orig);
 581         return (!ret) ? count : ret;
 582 }
 583
 584 static ssize_t rd_show_configfs_dev_params(struct se_device *dev, char *b)
 585 {
 586         struct rd_dev *rd_dev = RD_DEV(dev);
 587
 588         ssize_t bl = sprintf(b, "TCM RamDisk ID: %u  RamDisk Makeup: rd_mcp\n",
 589                         rd_dev->rd_dev_id);
 590         bl += sprintf(b + bl, "        PAGES/PAGE_SIZE: %u*%lu"
 591                         "  SG_table_count: %u  nullio: %d\n", rd_dev->rd_page_count,
 592                         PAGE_SIZE, rd_dev->sg_table_count,
 593                         !!(rd_dev->rd_flags & RDF_NULLIO));
 594         return bl;
 595 }
 596
 597 static sector_t rd_get_blocks(struct se_device *dev)
 598 {
 599         struct rd_dev *rd_dev = RD_DEV(dev);
 600
 601         unsigned long long blocks_long = ((rd_dev->rd_page_count * PAGE_SIZE) /
 602                         dev->dev_attrib.block_size) - 1;
 603
 604         return blocks_long;
 605 }
 606
 607 static int rd_init_prot(struct se_device *dev)
 608 {
 609         struct rd_dev *rd_dev = RD_DEV(dev);
 610
 611         if (!dev->dev_attrib.pi_prot_type)
 612                 return 0;
 613
 614         return rd_build_prot_space(rd_dev, dev->prot_length,
 615                                    dev->dev_attrib.block_size);
 616 }
 617
 618 static void rd_free_prot(struct se_device *dev)
 619 {
 620         struct rd_dev *rd_dev = RD_DEV(dev);
 621
 622         rd_release_prot_space(rd_dev);
 623 }
 624
 625 static struct sbc_ops rd_sbc_ops = {
 626         .execute_rw             = rd_execute_rw,
 627 };
 628
 629 static sense_reason_t
 630 rd_parse_cdb(struct se_cmd *cmd)
 631 {
 632         return sbc_parse_cdb(cmd, &rd_sbc_ops);
 633 }
 634
 635 static struct se_subsystem_api rd_mcp_template = {
 636         .name                   = "rd_mcp",
 637         .inquiry_prod           = "RAMDISK-MCP",
 638         .inquiry_rev            = RD_MCP_VERSION,
 639         .transport_type         = TRANSPORT_PLUGIN_VHBA_VDEV,
 640         .attach_hba             = rd_attach_hba,
 641         .detach_hba             = rd_detach_hba,
 642         .alloc_device           = rd_alloc_device,
 643         .configure_device       = rd_configure_device,
 644         .free_device            = rd_free_device,
 645         .parse_cdb              = rd_parse_cdb,
 646         .set_configfs_dev_params = rd_set_configfs_dev_params,
 647         .show_configfs_dev_params = rd_show_configfs_dev_params,
 648         .get_device_type        = sbc_get_device_type,
 649         .get_blocks             = rd_get_blocks,
 650         .init_prot              = rd_init_prot,
 651         .free_prot              = rd_free_prot,
 652 };
 653
 654 int __init rd_module_init(void)
 655 {
 656         int ret;
 657
 658         ret = transport_subsystem_register(&rd_mcp_template);
 659         if (ret < 0) {
 660                 return ret;
 661         }
 662
 663         return 0;
 664 }
 665
 666 void rd_module_exit(void)
 667 {
 668         transport_subsystem_release(&rd_mcp_template);
 669 }