Pileus Git - ~andy/linux/blob - 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  * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
   8  * Copyright (c) 2005, 2006, 2007 SBE, Inc.
   9  * Copyright (c) 2007-2010 Rising Tide Systems
  10  * Copyright (c) 2008-2010 Linux-iSCSI.org
  11  *
  12  * Nicholas A. Bellinger <nab@kernel.org>
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, write to the Free Software
  26  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  *
  28  ******************************************************************************/
  29
  30 #include <linux/version.h>
  31 #include <linux/string.h>
  32 #include <linux/parser.h>
  33 #include <linux/timer.h>
  34 #include <linux/blkdev.h>
  35 #include <linux/slab.h>
  36 #include <linux/spinlock.h>
  37 #include <scsi/scsi.h>
  38 #include <scsi/scsi_host.h>
  39
  40 #include <target/target_core_base.h>
  41 #include <target/target_core_device.h>
  42 #include <target/target_core_transport.h>
  43 #include <target/target_core_fabric_ops.h>
  44
  45 #include "target_core_rd.h"
  46
  47 static struct se_subsystem_api rd_dr_template;
  48 static struct se_subsystem_api rd_mcp_template;
  49
  50 /* #define DEBUG_RAMDISK_MCP */
  51 /* #define DEBUG_RAMDISK_DR */
  52
  53 /*      rd_attach_hba(): (Part of se_subsystem_api_t template)
  54  *
  55  *
  56  */
  57 static int rd_attach_hba(struct se_hba *hba, u32 host_id)
  58 {
  59         struct rd_host *rd_host;
  60
  61         rd_host = kzalloc(sizeof(struct rd_host), GFP_KERNEL);
  62         if (!(rd_host)) {
  63                 printk(KERN_ERR "Unable to allocate memory for struct rd_host\n");
  64                 return -ENOMEM;
  65         }
  66
  67         rd_host->rd_host_id = host_id;
  68
  69         atomic_set(&hba->left_queue_depth, RD_HBA_QUEUE_DEPTH);
  70         atomic_set(&hba->max_queue_depth, RD_HBA_QUEUE_DEPTH);
  71         hba->hba_ptr = (void *) rd_host;
  72
  73         printk(KERN_INFO "CORE_HBA[%d] - TCM Ramdisk HBA Driver %s on"
  74                 " Generic Target Core Stack %s\n", hba->hba_id,
  75                 RD_HBA_VERSION, TARGET_CORE_MOD_VERSION);
  76         printk(KERN_INFO "CORE_HBA[%d] - Attached Ramdisk HBA: %u to Generic"
  77                 " Target Core TCQ Depth: %d MaxSectors: %u\n", hba->hba_id,
  78                 rd_host->rd_host_id, atomic_read(&hba->max_queue_depth),
  79                 RD_MAX_SECTORS);
  80
  81         return 0;
  82 }
  83
  84 static void rd_detach_hba(struct se_hba *hba)
  85 {
  86         struct rd_host *rd_host = hba->hba_ptr;
  87
  88         printk(KERN_INFO "CORE_HBA[%d] - Detached Ramdisk HBA: %u from"
  89                 " Generic Target Core\n", hba->hba_id, rd_host->rd_host_id);
  90
  91         kfree(rd_host);
  92         hba->hba_ptr = NULL;
  93 }
  94
  95 /*      rd_release_device_space():
  96  *
  97  *
  98  */
  99 static void rd_release_device_space(struct rd_dev *rd_dev)
 100 {
 101         u32 i, j, page_count = 0, sg_per_table;
 102         struct rd_dev_sg_table *sg_table;
 103         struct page *pg;
 104         struct scatterlist *sg;
 105
 106         if (!rd_dev->sg_table_array || !rd_dev->sg_table_count)
 107                 return;
 108
 109         sg_table = rd_dev->sg_table_array;
 110
 111         for (i = 0; i < rd_dev->sg_table_count; i++) {
 112                 sg = sg_table[i].sg_table;
 113                 sg_per_table = sg_table[i].rd_sg_count;
 114
 115                 for (j = 0; j < sg_per_table; j++) {
 116                         pg = sg_page(&sg[j]);
 117                         if ((pg)) {
 118                                 __free_page(pg);
 119                                 page_count++;
 120                         }
 121                 }
 122
 123                 kfree(sg);
 124         }
 125
 126         printk(KERN_INFO "CORE_RD[%u] - Released device space for Ramdisk"
 127                 " Device ID: %u, pages %u in %u tables total bytes %lu\n",
 128                 rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
 129                 rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
 130
 131         kfree(sg_table);
 132         rd_dev->sg_table_array = NULL;
 133         rd_dev->sg_table_count = 0;
 134 }
 135
 136
 137 /*      rd_build_device_space():
 138  *
 139  *
 140  */
 141 static int rd_build_device_space(struct rd_dev *rd_dev)
 142 {
 143         u32 i = 0, j, page_offset = 0, sg_per_table, sg_tables, total_sg_needed;
 144         u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
 145                                 sizeof(struct scatterlist));
 146         struct rd_dev_sg_table *sg_table;
 147         struct page *pg;
 148         struct scatterlist *sg;
 149
 150         if (rd_dev->rd_page_count <= 0) {
 151                 printk(KERN_ERR "Illegal page count: %u for Ramdisk device\n",
 152                         rd_dev->rd_page_count);
 153                 return -1;
 154         }
 155         total_sg_needed = rd_dev->rd_page_count;
 156
 157         sg_tables = (total_sg_needed / max_sg_per_table) + 1;
 158
 159         sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
 160         if (!(sg_table)) {
 161                 printk(KERN_ERR "Unable to allocate memory for Ramdisk"
 162                         " scatterlist tables\n");
 163                 return -1;
 164         }
 165
 166         rd_dev->sg_table_array = sg_table;
 167         rd_dev->sg_table_count = sg_tables;
 168
 169         while (total_sg_needed) {
 170                 sg_per_table = (total_sg_needed > max_sg_per_table) ?
 171                         max_sg_per_table : total_sg_needed;
 172
 173                 sg = kzalloc(sg_per_table * sizeof(struct scatterlist),
 174                                 GFP_KERNEL);
 175                 if (!(sg)) {
 176                         printk(KERN_ERR "Unable to allocate scatterlist array"
 177                                 " for struct rd_dev\n");
 178                         return -1;
 179                 }
 180
 181                 sg_init_table((struct scatterlist *)&sg[0], sg_per_table);
 182
 183                 sg_table[i].sg_table = sg;
 184                 sg_table[i].rd_sg_count = sg_per_table;
 185                 sg_table[i].page_start_offset = page_offset;
 186                 sg_table[i++].page_end_offset = (page_offset + sg_per_table)
 187                                                 - 1;
 188
 189                 for (j = 0; j < sg_per_table; j++) {
 190                         pg = alloc_pages(GFP_KERNEL, 0);
 191                         if (!(pg)) {
 192                                 printk(KERN_ERR "Unable to allocate scatterlist"
 193                                         " pages for struct rd_dev_sg_table\n");
 194                                 return -1;
 195                         }
 196                         sg_assign_page(&sg[j], pg);
 197                         sg[j].length = PAGE_SIZE;
 198                 }
 199
 200                 page_offset += sg_per_table;
 201                 total_sg_needed -= sg_per_table;
 202         }
 203
 204         printk(KERN_INFO "CORE_RD[%u] - Built Ramdisk Device ID: %u space of"
 205                 " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
 206                 rd_dev->rd_dev_id, rd_dev->rd_page_count,
 207                 rd_dev->sg_table_count);
 208
 209         return 0;
 210 }
 211
 212 static void *rd_allocate_virtdevice(
 213         struct se_hba *hba,
 214         const char *name,
 215         int rd_direct)
 216 {
 217         struct rd_dev *rd_dev;
 218         struct rd_host *rd_host = hba->hba_ptr;
 219
 220         rd_dev = kzalloc(sizeof(struct rd_dev), GFP_KERNEL);
 221         if (!(rd_dev)) {
 222                 printk(KERN_ERR "Unable to allocate memory for struct rd_dev\n");
 223                 return NULL;
 224         }
 225
 226         rd_dev->rd_host = rd_host;
 227         rd_dev->rd_direct = rd_direct;
 228
 229         return rd_dev;
 230 }
 231
 232 static void *rd_DIRECT_allocate_virtdevice(struct se_hba *hba, const char *name)
 233 {
 234         return rd_allocate_virtdevice(hba, name, 1);
 235 }
 236
 237 static void *rd_MEMCPY_allocate_virtdevice(struct se_hba *hba, const char *name)
 238 {
 239         return rd_allocate_virtdevice(hba, name, 0);
 240 }
 241
 242 /*      rd_create_virtdevice():
 243  *
 244  *
 245  */
 246 static struct se_device *rd_create_virtdevice(
 247         struct se_hba *hba,
 248         struct se_subsystem_dev *se_dev,
 249         void *p,
 250         int rd_direct)
 251 {
 252         struct se_device *dev;
 253         struct se_dev_limits dev_limits;
 254         struct rd_dev *rd_dev = p;
 255         struct rd_host *rd_host = hba->hba_ptr;
 256         int dev_flags = 0, ret = -EINVAL;
 257         char prod[16], rev[4];
 258
 259         memset(&dev_limits, 0, sizeof(struct se_dev_limits));
 260
 261         if (rd_build_device_space(rd_dev) < 0) {
 262                 ret = -ENOMEM;
 263                 goto fail;
 264         }
 265
 266         snprintf(prod, 16, "RAMDISK-%s", (rd_dev->rd_direct) ? "DR" : "MCP");
 267         snprintf(rev, 4, "%s", (rd_dev->rd_direct) ? RD_DR_VERSION :
 268                                                 RD_MCP_VERSION);
 269
 270         dev_limits.limits.logical_block_size = RD_BLOCKSIZE;
 271         dev_limits.limits.max_hw_sectors = RD_MAX_SECTORS;
 272         dev_limits.limits.max_sectors = RD_MAX_SECTORS;
 273         dev_limits.hw_queue_depth = RD_MAX_DEVICE_QUEUE_DEPTH;
 274         dev_limits.queue_depth = RD_DEVICE_QUEUE_DEPTH;
 275
 276         dev = transport_add_device_to_core_hba(hba,
 277                         (rd_dev->rd_direct) ? &rd_dr_template :
 278                         &rd_mcp_template, se_dev, dev_flags, (void *)rd_dev,
 279                         &dev_limits, prod, rev);
 280         if (!(dev))
 281                 goto fail;
 282
 283         rd_dev->rd_dev_id = rd_host->rd_host_dev_id_count++;
 284         rd_dev->rd_queue_depth = dev->queue_depth;
 285
 286         printk(KERN_INFO "CORE_RD[%u] - Added TCM %s Ramdisk Device ID: %u of"
 287                 " %u pages in %u tables, %lu total bytes\n",
 288                 rd_host->rd_host_id, (!rd_dev->rd_direct) ? "MEMCPY" :
 289                 "DIRECT", rd_dev->rd_dev_id, rd_dev->rd_page_count,
 290                 rd_dev->sg_table_count,
 291                 (unsigned long)(rd_dev->rd_page_count * PAGE_SIZE));
 292
 293         return dev;
 294
 295 fail:
 296         rd_release_device_space(rd_dev);
 297         return ERR_PTR(ret);
 298 }
 299
 300 static struct se_device *rd_DIRECT_create_virtdevice(
 301         struct se_hba *hba,
 302         struct se_subsystem_dev *se_dev,
 303         void *p)
 304 {
 305         return rd_create_virtdevice(hba, se_dev, p, 1);
 306 }
 307
 308 static struct se_device *rd_MEMCPY_create_virtdevice(
 309         struct se_hba *hba,
 310         struct se_subsystem_dev *se_dev,
 311         void *p)
 312 {
 313         return rd_create_virtdevice(hba, se_dev, p, 0);
 314 }
 315
 316 /*      rd_free_device(): (Part of se_subsystem_api_t template)
 317  *
 318  *
 319  */
 320 static void rd_free_device(void *p)
 321 {
 322         struct rd_dev *rd_dev = p;
 323
 324         rd_release_device_space(rd_dev);
 325         kfree(rd_dev);
 326 }
 327
 328 static inline struct rd_request *RD_REQ(struct se_task *task)
 329 {
 330         return container_of(task, struct rd_request, rd_task);
 331 }
 332
 333 static struct se_task *
 334 rd_alloc_task(struct se_cmd *cmd)
 335 {
 336         struct rd_request *rd_req;
 337
 338         rd_req = kzalloc(sizeof(struct rd_request), GFP_KERNEL);
 339         if (!rd_req) {
 340                 printk(KERN_ERR "Unable to allocate struct rd_request\n");
 341                 return NULL;
 342         }
 343         rd_req->rd_dev = SE_DEV(cmd)->dev_ptr;
 344
 345         return &rd_req->rd_task;
 346 }
 347
 348 /*      rd_get_sg_table():
 349  *
 350  *
 351  */
 352 static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page)
 353 {
 354         u32 i;
 355         struct rd_dev_sg_table *sg_table;
 356
 357         for (i = 0; i < rd_dev->sg_table_count; i++) {
 358                 sg_table = &rd_dev->sg_table_array[i];
 359                 if ((sg_table->page_start_offset <= page) &&
 360                     (sg_table->page_end_offset >= page))
 361                         return sg_table;
 362         }
 363
 364         printk(KERN_ERR "Unable to locate struct rd_dev_sg_table for page: %u\n",
 365                         page);
 366
 367         return NULL;
 368 }
 369
 370 /*      rd_MEMCPY_read():
 371  *
 372  *
 373  */
 374 static int rd_MEMCPY_read(struct rd_request *req)
 375 {
 376         struct se_task *task = &req->rd_task;
 377         struct rd_dev *dev = req->rd_dev;
 378         struct rd_dev_sg_table *table;
 379         struct scatterlist *sg_d, *sg_s;
 380         void *dst, *src;
 381         u32 i = 0, j = 0, dst_offset = 0, src_offset = 0;
 382         u32 length, page_end = 0, table_sg_end;
 383         u32 rd_offset = req->rd_offset;
 384
 385         table = rd_get_sg_table(dev, req->rd_page);
 386         if (!(table))
 387                 return -1;
 388
 389         table_sg_end = (table->page_end_offset - req->rd_page);
 390         sg_d = task->task_sg;
 391         sg_s = &table->sg_table[req->rd_page - table->page_start_offset];
 392 #ifdef DEBUG_RAMDISK_MCP
 393         printk(KERN_INFO "RD[%u]: Read LBA: %llu, Size: %u Page: %u, Offset:"
 394                 " %u\n", dev->rd_dev_id, task->task_lba, req->rd_size,
 395                 req->rd_page, req->rd_offset);
 396 #endif
 397         src_offset = rd_offset;
 398
 399         while (req->rd_size) {
 400                 if ((sg_d[i].length - dst_offset) <
 401                     (sg_s[j].length - src_offset)) {
 402                         length = (sg_d[i].length - dst_offset);
 403 #ifdef DEBUG_RAMDISK_MCP
 404                         printk(KERN_INFO "Step 1 - sg_d[%d]: %p length: %d"
 405                                 " offset: %u sg_s[%d].length: %u\n", i,
 406                                 &sg_d[i], sg_d[i].length, sg_d[i].offset, j,
 407                                 sg_s[j].length);
 408                         printk(KERN_INFO "Step 1 - length: %u dst_offset: %u"
 409                                 " src_offset: %u\n", length, dst_offset,
 410                                 src_offset);
 411 #endif
 412                         if (length > req->rd_size)
 413                                 length = req->rd_size;
 414
 415                         dst = sg_virt(&sg_d[i++]) + dst_offset;
 416                         if (!dst)
 417                                 BUG();
 418
 419                         src = sg_virt(&sg_s[j]) + src_offset;
 420                         if (!src)
 421                                 BUG();
 422
 423                         dst_offset = 0;
 424                         src_offset = length;
 425                         page_end = 0;
 426                 } else {
 427                         length = (sg_s[j].length - src_offset);
 428 #ifdef DEBUG_RAMDISK_MCP
 429                         printk(KERN_INFO "Step 2 - sg_d[%d]: %p length: %d"
 430                                 " offset: %u sg_s[%d].length: %u\n", i,
 431                                 &sg_d[i], sg_d[i].length, sg_d[i].offset,
 432                                 j, sg_s[j].length);
 433                         printk(KERN_INFO "Step 2 - length: %u dst_offset: %u"
 434                                 " src_offset: %u\n", length, dst_offset,
 435                                 src_offset);
 436 #endif
 437                         if (length > req->rd_size)
 438                                 length = req->rd_size;
 439
 440                         dst = sg_virt(&sg_d[i]) + dst_offset;
 441                         if (!dst)
 442                                 BUG();
 443
 444                         if (sg_d[i].length == length) {
 445                                 i++;
 446                                 dst_offset = 0;
 447                         } else
 448                                 dst_offset = length;
 449
 450                         src = sg_virt(&sg_s[j++]) + src_offset;
 451                         if (!src)
 452                                 BUG();
 453
 454                         src_offset = 0;
 455                         page_end = 1;
 456                 }
 457
 458                 memcpy(dst, src, length);
 459
 460 #ifdef DEBUG_RAMDISK_MCP
 461                 printk(KERN_INFO "page: %u, remaining size: %u, length: %u,"
 462                         " i: %u, j: %u\n", req->rd_page,
 463                         (req->rd_size - length), length, i, j);
 464 #endif
 465                 req->rd_size -= length;
 466                 if (!(req->rd_size))
 467                         return 0;
 468
 469                 if (!page_end)
 470                         continue;
 471
 472                 if (++req->rd_page <= table->page_end_offset) {
 473 #ifdef DEBUG_RAMDISK_MCP
 474                         printk(KERN_INFO "page: %u in same page table\n",
 475                                 req->rd_page);
 476 #endif
 477                         continue;
 478                 }
 479 #ifdef DEBUG_RAMDISK_MCP
 480                 printk(KERN_INFO "getting new page table for page: %u\n",
 481                                 req->rd_page);
 482 #endif
 483                 table = rd_get_sg_table(dev, req->rd_page);
 484                 if (!(table))
 485                         return -1;
 486
 487                 sg_s = &table->sg_table[j = 0];
 488         }
 489
 490         return 0;
 491 }
 492
 493 /*      rd_MEMCPY_write():
 494  *
 495  *
 496  */
 497 static int rd_MEMCPY_write(struct rd_request *req)
 498 {
 499         struct se_task *task = &req->rd_task;
 500         struct rd_dev *dev = req->rd_dev;
 501         struct rd_dev_sg_table *table;
 502         struct scatterlist *sg_d, *sg_s;
 503         void *dst, *src;
 504         u32 i = 0, j = 0, dst_offset = 0, src_offset = 0;
 505         u32 length, page_end = 0, table_sg_end;
 506         u32 rd_offset = req->rd_offset;
 507
 508         table = rd_get_sg_table(dev, req->rd_page);
 509         if (!(table))
 510                 return -1;
 511
 512         table_sg_end = (table->page_end_offset - req->rd_page);
 513         sg_d = &table->sg_table[req->rd_page - table->page_start_offset];
 514         sg_s = task->task_sg;
 515 #ifdef DEBUG_RAMDISK_MCP
 516         printk(KERN_INFO "RD[%d] Write LBA: %llu, Size: %u, Page: %u,"
 517                 " Offset: %u\n", dev->rd_dev_id, task->task_lba, req->rd_size,
 518                 req->rd_page, req->rd_offset);
 519 #endif
 520         dst_offset = rd_offset;
 521
 522         while (req->rd_size) {
 523                 if ((sg_s[i].length - src_offset) <
 524                     (sg_d[j].length - dst_offset)) {
 525                         length = (sg_s[i].length - src_offset);
 526 #ifdef DEBUG_RAMDISK_MCP
 527                         printk(KERN_INFO "Step 1 - sg_s[%d]: %p length: %d"
 528                                 " offset: %d sg_d[%d].length: %u\n", i,
 529                                 &sg_s[i], sg_s[i].length, sg_s[i].offset,
 530                                 j, sg_d[j].length);
 531                         printk(KERN_INFO "Step 1 - length: %u src_offset: %u"
 532                                 " dst_offset: %u\n", length, src_offset,
 533                                 dst_offset);
 534 #endif
 535                         if (length > req->rd_size)
 536                                 length = req->rd_size;
 537
 538                         src = sg_virt(&sg_s[i++]) + src_offset;
 539                         if (!src)
 540                                 BUG();
 541
 542                         dst = sg_virt(&sg_d[j]) + dst_offset;
 543                         if (!dst)
 544                                 BUG();
 545
 546                         src_offset = 0;
 547                         dst_offset = length;
 548                         page_end = 0;
 549                 } else {
 550                         length = (sg_d[j].length - dst_offset);
 551 #ifdef DEBUG_RAMDISK_MCP
 552                         printk(KERN_INFO "Step 2 - sg_s[%d]: %p length: %d"
 553                                 " offset: %d sg_d[%d].length: %u\n", i,
 554                                 &sg_s[i], sg_s[i].length, sg_s[i].offset,
 555                                 j, sg_d[j].length);
 556                         printk(KERN_INFO "Step 2 - length: %u src_offset: %u"
 557                                 " dst_offset: %u\n", length, src_offset,
 558                                 dst_offset);
 559 #endif
 560                         if (length > req->rd_size)
 561                                 length = req->rd_size;
 562
 563                         src = sg_virt(&sg_s[i]) + src_offset;
 564                         if (!src)
 565                                 BUG();
 566
 567                         if (sg_s[i].length == length) {
 568                                 i++;
 569                                 src_offset = 0;
 570                         } else
 571                                 src_offset = length;
 572
 573                         dst = sg_virt(&sg_d[j++]) + dst_offset;
 574                         if (!dst)
 575                                 BUG();
 576
 577                         dst_offset = 0;
 578                         page_end = 1;
 579                 }
 580
 581                 memcpy(dst, src, length);
 582
 583 #ifdef DEBUG_RAMDISK_MCP
 584                 printk(KERN_INFO "page: %u, remaining size: %u, length: %u,"
 585                         " i: %u, j: %u\n", req->rd_page,
 586                         (req->rd_size - length), length, i, j);
 587 #endif
 588                 req->rd_size -= length;
 589                 if (!(req->rd_size))
 590                         return 0;
 591
 592                 if (!page_end)
 593                         continue;
 594
 595                 if (++req->rd_page <= table->page_end_offset) {
 596 #ifdef DEBUG_RAMDISK_MCP
 597                         printk(KERN_INFO "page: %u in same page table\n",
 598                                 req->rd_page);
 599 #endif
 600                         continue;
 601                 }
 602 #ifdef DEBUG_RAMDISK_MCP
 603                 printk(KERN_INFO "getting new page table for page: %u\n",
 604                                 req->rd_page);
 605 #endif
 606                 table = rd_get_sg_table(dev, req->rd_page);
 607                 if (!(table))
 608                         return -1;
 609
 610                 sg_d = &table->sg_table[j = 0];
 611         }
 612
 613         return 0;
 614 }
 615
 616 /*      rd_MEMCPY_do_task(): (Part of se_subsystem_api_t template)
 617  *
 618  *
 619  */
 620 static int rd_MEMCPY_do_task(struct se_task *task)
 621 {
 622         struct se_device *dev = task->se_dev;
 623         struct rd_request *req = RD_REQ(task);
 624         unsigned long long lba;
 625         int ret;
 626
 627         req->rd_page = (task->task_lba * DEV_ATTRIB(dev)->block_size) / PAGE_SIZE;
 628         lba = task->task_lba;
 629         req->rd_offset = (do_div(lba,
 630                           (PAGE_SIZE / DEV_ATTRIB(dev)->block_size))) *
 631                            DEV_ATTRIB(dev)->block_size;
 632         req->rd_size = task->task_size;
 633
 634         if (task->task_data_direction == DMA_FROM_DEVICE)
 635                 ret = rd_MEMCPY_read(req);
 636         else
 637                 ret = rd_MEMCPY_write(req);
 638
 639         if (ret != 0)
 640                 return ret;
 641
 642         task->task_scsi_status = GOOD;
 643         transport_complete_task(task, 1);
 644
 645         return PYX_TRANSPORT_SENT_TO_TRANSPORT;
 646 }
 647
 648 /*      rd_DIRECT_with_offset():
 649  *
 650  *
 651  */
 652 static int rd_DIRECT_with_offset(
 653         struct se_task *task,
 654         struct list_head *se_mem_list,
 655         u32 *se_mem_cnt,
 656         u32 *task_offset)
 657 {
 658         struct rd_request *req = RD_REQ(task);
 659         struct rd_dev *dev = req->rd_dev;
 660         struct rd_dev_sg_table *table;
 661         struct se_mem *se_mem;
 662         struct scatterlist *sg_s;
 663         u32 j = 0, set_offset = 1;
 664         u32 get_next_table = 0, offset_length, table_sg_end;
 665
 666         table = rd_get_sg_table(dev, req->rd_page);
 667         if (!(table))
 668                 return -1;
 669
 670         table_sg_end = (table->page_end_offset - req->rd_page);
 671         sg_s = &table->sg_table[req->rd_page - table->page_start_offset];
 672 #ifdef DEBUG_RAMDISK_DR
 673         printk(KERN_INFO "%s DIRECT LBA: %llu, Size: %u Page: %u, Offset: %u\n",
 674                 (task->task_data_direction == DMA_TO_DEVICE) ?
 675                         "Write" : "Read",
 676                 task->task_lba, req->rd_size, req->rd_page, req->rd_offset);
 677 #endif
 678         while (req->rd_size) {
 679                 se_mem = kmem_cache_zalloc(se_mem_cache, GFP_KERNEL);
 680                 if (!(se_mem)) {
 681                         printk(KERN_ERR "Unable to allocate struct se_mem\n");
 682                         return -1;
 683                 }
 684                 INIT_LIST_HEAD(&se_mem->se_list);
 685
 686                 if (set_offset) {
 687                         offset_length = sg_s[j].length - req->rd_offset;
 688                         if (offset_length > req->rd_size)
 689                                 offset_length = req->rd_size;
 690
 691                         se_mem->se_page = sg_page(&sg_s[j++]);
 692                         se_mem->se_off = req->rd_offset;
 693                         se_mem->se_len = offset_length;
 694
 695                         set_offset = 0;
 696                         get_next_table = (j > table_sg_end);
 697                         goto check_eot;
 698                 }
 699
 700                 offset_length = (req->rd_size < req->rd_offset) ?
 701                         req->rd_size : req->rd_offset;
 702
 703                 se_mem->se_page = sg_page(&sg_s[j]);
 704                 se_mem->se_len = offset_length;
 705
 706                 set_offset = 1;
 707
 708 check_eot:
 709 #ifdef DEBUG_RAMDISK_DR
 710                 printk(KERN_INFO "page: %u, size: %u, offset_length: %u, j: %u"
 711                         " se_mem: %p, se_page: %p se_off: %u se_len: %u\n",
 712                         req->rd_page, req->rd_size, offset_length, j, se_mem,
 713                         se_mem->se_page, se_mem->se_off, se_mem->se_len);
 714 #endif
 715                 list_add_tail(&se_mem->se_list, se_mem_list);
 716                 (*se_mem_cnt)++;
 717
 718                 req->rd_size -= offset_length;
 719                 if (!(req->rd_size))
 720                         goto out;
 721
 722                 if (!set_offset && !get_next_table)
 723                         continue;
 724
 725                 if (++req->rd_page <= table->page_end_offset) {
 726 #ifdef DEBUG_RAMDISK_DR
 727                         printk(KERN_INFO "page: %u in same page table\n",
 728                                         req->rd_page);
 729 #endif
 730                         continue;
 731                 }
 732 #ifdef DEBUG_RAMDISK_DR
 733                 printk(KERN_INFO "getting new page table for page: %u\n",
 734                                 req->rd_page);
 735 #endif
 736                 table = rd_get_sg_table(dev, req->rd_page);
 737                 if (!(table))
 738                         return -1;
 739
 740                 sg_s = &table->sg_table[j = 0];
 741         }
 742
 743 out:
 744         T_TASK(task->task_se_cmd)->t_tasks_se_num += *se_mem_cnt;
 745 #ifdef DEBUG_RAMDISK_DR
 746         printk(KERN_INFO "RD_DR - Allocated %u struct se_mem segments for task\n",
 747                         *se_mem_cnt);
 748 #endif
 749         return 0;
 750 }
 751
 752 /*      rd_DIRECT_without_offset():
 753  *
 754  *
 755  */
 756 static int rd_DIRECT_without_offset(
 757         struct se_task *task,
 758         struct list_head *se_mem_list,
 759         u32 *se_mem_cnt,
 760         u32 *task_offset)
 761 {
 762         struct rd_request *req = RD_REQ(task);
 763         struct rd_dev *dev = req->rd_dev;
 764         struct rd_dev_sg_table *table;
 765         struct se_mem *se_mem;
 766         struct scatterlist *sg_s;
 767         u32 length, j = 0;
 768
 769         table = rd_get_sg_table(dev, req->rd_page);
 770         if (!(table))
 771                 return -1;
 772
 773         sg_s = &table->sg_table[req->rd_page - table->page_start_offset];
 774 #ifdef DEBUG_RAMDISK_DR
 775         printk(KERN_INFO "%s DIRECT LBA: %llu, Size: %u, Page: %u\n",
 776                 (task->task_data_direction == DMA_TO_DEVICE) ?
 777                         "Write" : "Read",
 778                 task->task_lba, req->rd_size, req->rd_page);
 779 #endif
 780         while (req->rd_size) {
 781                 se_mem = kmem_cache_zalloc(se_mem_cache, GFP_KERNEL);
 782                 if (!(se_mem)) {
 783                         printk(KERN_ERR "Unable to allocate struct se_mem\n");
 784                         return -1;
 785                 }
 786                 INIT_LIST_HEAD(&se_mem->se_list);
 787
 788                 length = (req->rd_size < sg_s[j].length) ?
 789                         req->rd_size : sg_s[j].length;
 790
 791                 se_mem->se_page = sg_page(&sg_s[j++]);
 792                 se_mem->se_len = length;
 793
 794 #ifdef DEBUG_RAMDISK_DR
 795                 printk(KERN_INFO "page: %u, size: %u, j: %u se_mem: %p,"
 796                         " se_page: %p se_off: %u se_len: %u\n", req->rd_page,
 797                         req->rd_size, j, se_mem, se_mem->se_page,
 798                         se_mem->se_off, se_mem->se_len);
 799 #endif
 800                 list_add_tail(&se_mem->se_list, se_mem_list);
 801                 (*se_mem_cnt)++;
 802
 803                 req->rd_size -= length;
 804                 if (!(req->rd_size))
 805                         goto out;
 806
 807                 if (++req->rd_page <= table->page_end_offset) {
 808 #ifdef DEBUG_RAMDISK_DR
 809                         printk("page: %u in same page table\n",
 810                                 req->rd_page);
 811 #endif
 812                         continue;
 813                 }
 814 #ifdef DEBUG_RAMDISK_DR
 815                 printk(KERN_INFO "getting new page table for page: %u\n",
 816                                 req->rd_page);
 817 #endif
 818                 table = rd_get_sg_table(dev, req->rd_page);
 819                 if (!(table))
 820                         return -1;
 821
 822                 sg_s = &table->sg_table[j = 0];
 823         }
 824
 825 out:
 826         T_TASK(task->task_se_cmd)->t_tasks_se_num += *se_mem_cnt;
 827 #ifdef DEBUG_RAMDISK_DR
 828         printk(KERN_INFO "RD_DR - Allocated %u struct se_mem segments for task\n",
 829                         *se_mem_cnt);
 830 #endif
 831         return 0;
 832 }
 833
 834 /*      rd_DIRECT_do_se_mem_map():
 835  *
 836  *
 837  */
 838 static int rd_DIRECT_do_se_mem_map(
 839         struct se_task *task,
 840         struct list_head *se_mem_list,
 841         void *in_mem,
 842         struct se_mem *in_se_mem,
 843         struct se_mem **out_se_mem,
 844         u32 *se_mem_cnt,
 845         u32 *task_offset_in)
 846 {
 847         struct se_cmd *cmd = task->task_se_cmd;
 848         struct rd_request *req = RD_REQ(task);
 849         u32 task_offset = *task_offset_in;
 850         unsigned long long lba;
 851         int ret;
 852
 853         req->rd_page = ((task->task_lba * DEV_ATTRIB(task->se_dev)->block_size) /
 854                         PAGE_SIZE);
 855         lba = task->task_lba;
 856         req->rd_offset = (do_div(lba,
 857                           (PAGE_SIZE / DEV_ATTRIB(task->se_dev)->block_size))) *
 858                            DEV_ATTRIB(task->se_dev)->block_size;
 859         req->rd_size = task->task_size;
 860
 861         if (req->rd_offset)
 862                 ret = rd_DIRECT_with_offset(task, se_mem_list, se_mem_cnt,
 863                                 task_offset_in);
 864         else
 865                 ret = rd_DIRECT_without_offset(task, se_mem_list, se_mem_cnt,
 866                                 task_offset_in);
 867
 868         if (ret < 0)
 869                 return ret;
 870
 871         if (CMD_TFO(cmd)->task_sg_chaining == 0)
 872                 return 0;
 873         /*
 874          * Currently prevent writers from multiple HW fabrics doing
 875          * pci_map_sg() to RD_DR's internal scatterlist memory.
 876          */
 877         if (cmd->data_direction == DMA_TO_DEVICE) {
 878                 printk(KERN_ERR "DMA_TO_DEVICE not supported for"
 879                                 " RAMDISK_DR with task_sg_chaining=1\n");
 880                 return -1;
 881         }
 882         /*
 883          * Special case for if task_sg_chaining is enabled, then
 884          * we setup struct se_task->task_sg[], as it will be used by
 885          * transport_do_task_sg_chain() for creating chainged SGLs
 886          * across multiple struct se_task->task_sg[].
 887          */
 888         if (!(transport_calc_sg_num(task,
 889                         list_entry(T_TASK(cmd)->t_mem_list->next,
 890                                    struct se_mem, se_list),
 891                         task_offset)))
 892                 return -1;
 893
 894         return transport_map_mem_to_sg(task, se_mem_list, task->task_sg,
 895                         list_entry(T_TASK(cmd)->t_mem_list->next,
 896                                    struct se_mem, se_list),
 897                         out_se_mem, se_mem_cnt, task_offset_in);
 898 }
 899
 900 /*      rd_DIRECT_do_task(): (Part of se_subsystem_api_t template)
 901  *
 902  *
 903  */
 904 static int rd_DIRECT_do_task(struct se_task *task)
 905 {
 906         /*
 907          * At this point the locally allocated RD tables have been mapped
 908          * to struct se_mem elements in rd_DIRECT_do_se_mem_map().
 909          */
 910         task->task_scsi_status = GOOD;
 911         transport_complete_task(task, 1);
 912
 913         return PYX_TRANSPORT_SENT_TO_TRANSPORT;
 914 }
 915
 916 /*      rd_free_task(): (Part of se_subsystem_api_t template)
 917  *
 918  *
 919  */
 920 static void rd_free_task(struct se_task *task)
 921 {
 922         kfree(RD_REQ(task));
 923 }
 924
 925 enum {
 926         Opt_rd_pages, Opt_err
 927 };
 928
 929 static match_table_t tokens = {
 930         {Opt_rd_pages, "rd_pages=%d"},
 931         {Opt_err, NULL}
 932 };
 933
 934 static ssize_t rd_set_configfs_dev_params(
 935         struct se_hba *hba,
 936         struct se_subsystem_dev *se_dev,
 937         const char *page,
 938         ssize_t count)
 939 {
 940         struct rd_dev *rd_dev = se_dev->se_dev_su_ptr;
 941         char *orig, *ptr, *opts;
 942         substring_t args[MAX_OPT_ARGS];
 943         int ret = 0, arg, token;
 944
 945         opts = kstrdup(page, GFP_KERNEL);
 946         if (!opts)
 947                 return -ENOMEM;
 948
 949         orig = opts;
 950
 951         while ((ptr = strsep(&opts, ",")) != NULL) {
 952                 if (!*ptr)
 953                         continue;
 954
 955                 token = match_token(ptr, tokens, args);
 956                 switch (token) {
 957                 case Opt_rd_pages:
 958                         match_int(args, &arg);
 959                         rd_dev->rd_page_count = arg;
 960                         printk(KERN_INFO "RAMDISK: Referencing Page"
 961                                 " Count: %u\n", rd_dev->rd_page_count);
 962                         rd_dev->rd_flags |= RDF_HAS_PAGE_COUNT;
 963                         break;
 964                 default:
 965                         break;
 966                 }
 967         }
 968
 969         kfree(orig);
 970         return (!ret) ? count : ret;
 971 }
 972
 973 static ssize_t rd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev)
 974 {
 975         struct rd_dev *rd_dev = se_dev->se_dev_su_ptr;
 976
 977         if (!(rd_dev->rd_flags & RDF_HAS_PAGE_COUNT)) {
 978                 printk(KERN_INFO "Missing rd_pages= parameter\n");
 979                 return -1;
 980         }
 981
 982         return 0;
 983 }
 984
 985 static ssize_t rd_show_configfs_dev_params(
 986         struct se_hba *hba,
 987         struct se_subsystem_dev *se_dev,
 988         char *b)
 989 {
 990         struct rd_dev *rd_dev = se_dev->se_dev_su_ptr;
 991         ssize_t bl = sprintf(b, "TCM RamDisk ID: %u  RamDisk Makeup: %s\n",
 992                         rd_dev->rd_dev_id, (rd_dev->rd_direct) ?
 993                         "rd_direct" : "rd_mcp");
 994         bl += sprintf(b + bl, "        PAGES/PAGE_SIZE: %u*%lu"
 995                         "  SG_table_count: %u\n", rd_dev->rd_page_count,
 996                         PAGE_SIZE, rd_dev->sg_table_count);
 997         return bl;
 998 }
 999
1000 /*      rd_get_cdb(): (Part of se_subsystem_api_t template)
1001  *
1002  *
1003  */
1004 static unsigned char *rd_get_cdb(struct se_task *task)
1005 {
1006         struct rd_request *req = RD_REQ(task);
1007
1008         return req->rd_scsi_cdb;
1009 }
1010
1011 static u32 rd_get_device_rev(struct se_device *dev)
1012 {
1013         return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
1014 }
1015
1016 static u32 rd_get_device_type(struct se_device *dev)
1017 {
1018         return TYPE_DISK;
1019 }
1020
1021 static sector_t rd_get_blocks(struct se_device *dev)
1022 {
1023         struct rd_dev *rd_dev = dev->dev_ptr;
1024         unsigned long long blocks_long = ((rd_dev->rd_page_count * PAGE_SIZE) /
1025                         DEV_ATTRIB(dev)->block_size) - 1;
1026
1027         return blocks_long;
1028 }
1029
1030 static struct se_subsystem_api rd_dr_template = {
1031         .name                   = "rd_dr",
1032         .transport_type         = TRANSPORT_PLUGIN_VHBA_VDEV,
1033         .attach_hba             = rd_attach_hba,
1034         .detach_hba             = rd_detach_hba,
1035         .allocate_virtdevice    = rd_DIRECT_allocate_virtdevice,
1036         .create_virtdevice      = rd_DIRECT_create_virtdevice,
1037         .free_device            = rd_free_device,
1038         .alloc_task             = rd_alloc_task,
1039         .do_task                = rd_DIRECT_do_task,
1040         .free_task              = rd_free_task,
1041         .check_configfs_dev_params = rd_check_configfs_dev_params,
1042         .set_configfs_dev_params = rd_set_configfs_dev_params,
1043         .show_configfs_dev_params = rd_show_configfs_dev_params,
1044         .get_cdb                = rd_get_cdb,
1045         .get_device_rev         = rd_get_device_rev,
1046         .get_device_type        = rd_get_device_type,
1047         .get_blocks             = rd_get_blocks,
1048         .do_se_mem_map          = rd_DIRECT_do_se_mem_map,
1049 };
1050
1051 static struct se_subsystem_api rd_mcp_template = {
1052         .name                   = "rd_mcp",
1053         .transport_type         = TRANSPORT_PLUGIN_VHBA_VDEV,
1054         .attach_hba             = rd_attach_hba,
1055         .detach_hba             = rd_detach_hba,
1056         .allocate_virtdevice    = rd_MEMCPY_allocate_virtdevice,
1057         .create_virtdevice      = rd_MEMCPY_create_virtdevice,
1058         .free_device            = rd_free_device,
1059         .alloc_task             = rd_alloc_task,
1060         .do_task                = rd_MEMCPY_do_task,
1061         .free_task              = rd_free_task,
1062         .check_configfs_dev_params = rd_check_configfs_dev_params,
1063         .set_configfs_dev_params = rd_set_configfs_dev_params,
1064         .show_configfs_dev_params = rd_show_configfs_dev_params,
1065         .get_cdb                = rd_get_cdb,
1066         .get_device_rev         = rd_get_device_rev,
1067         .get_device_type        = rd_get_device_type,
1068         .get_blocks             = rd_get_blocks,
1069 };
1070
1071 int __init rd_module_init(void)
1072 {
1073         int ret;
1074
1075         ret = transport_subsystem_register(&rd_dr_template);
1076         if (ret < 0)
1077                 return ret;
1078
1079         ret = transport_subsystem_register(&rd_mcp_template);
1080         if (ret < 0) {
1081                 transport_subsystem_release(&rd_dr_template);
1082                 return ret;
1083         }
1084
1085         return 0;
1086 }
1087
1088 void rd_module_exit(void)
1089 {
1090         transport_subsystem_release(&rd_dr_template);
1091         transport_subsystem_release(&rd_mcp_template);
1092 }