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; 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 goto fail; 263 264 snprintf(prod, 16, "RAMDISK-%s", (rd_dev->rd_direct) ? "DR" : "MCP"); 265 snprintf(rev, 4, "%s", (rd_dev->rd_direct) ? RD_DR_VERSION : 266 RD_MCP_VERSION); 267 268 dev_limits.limits.logical_block_size = RD_BLOCKSIZE; 269 dev_limits.limits.max_hw_sectors = RD_MAX_SECTORS; 270 dev_limits.limits.max_sectors = RD_MAX_SECTORS; 271 dev_limits.hw_queue_depth = RD_MAX_DEVICE_QUEUE_DEPTH; 272 dev_limits.queue_depth = RD_DEVICE_QUEUE_DEPTH; 273 274 dev = transport_add_device_to_core_hba(hba, 275 (rd_dev->rd_direct) ? &rd_dr_template : 276 &rd_mcp_template, se_dev, dev_flags, (void *)rd_dev, 277 &dev_limits, prod, rev); 278 if (!(dev)) 279 goto fail; 280 281 rd_dev->rd_dev_id = rd_host->rd_host_dev_id_count++; 282 rd_dev->rd_queue_depth = dev->queue_depth; 283 284 printk(KERN_INFO "CORE_RD[%u] - Added TCM %s Ramdisk Device ID: %u of" 285 " %u pages in %u tables, %lu total bytes\n", 286 rd_host->rd_host_id, (!rd_dev->rd_direct) ? "MEMCPY" : 287 "DIRECT", rd_dev->rd_dev_id, rd_dev->rd_page_count, 288 rd_dev->sg_table_count, 289 (unsigned long)(rd_dev->rd_page_count * PAGE_SIZE)); 290 291 return dev; 292 293 fail: 294 rd_release_device_space(rd_dev); 295 return NULL; 296 } 297 298 static struct se_device *rd_DIRECT_create_virtdevice( 299 struct se_hba *hba, 300 struct se_subsystem_dev *se_dev, 301 void *p) 302 { 303 return rd_create_virtdevice(hba, se_dev, p, 1); 304 } 305 306 static struct se_device *rd_MEMCPY_create_virtdevice( 307 struct se_hba *hba, 308 struct se_subsystem_dev *se_dev, 309 void *p) 310 { 311 return rd_create_virtdevice(hba, se_dev, p, 0); 312 } 313 314 /* rd_free_device(): (Part of se_subsystem_api_t template) 315 * 316 * 317 */ 318 static void rd_free_device(void *p) 319 { 320 struct rd_dev *rd_dev = p; 321 322 rd_release_device_space(rd_dev); 323 kfree(rd_dev); 324 } 325 326 static inline struct rd_request *RD_REQ(struct se_task *task) 327 { 328 return container_of(task, struct rd_request, rd_task); 329 } 330 331 static struct se_task * 332 rd_alloc_task(struct se_cmd *cmd) 333 { 334 struct rd_request *rd_req; 335 336 rd_req = kzalloc(sizeof(struct rd_request), GFP_KERNEL); 337 if (!rd_req) { 338 printk(KERN_ERR "Unable to allocate struct rd_request\n"); 339 return NULL; 340 } 341 rd_req->rd_dev = SE_DEV(cmd)->dev_ptr; 342 343 return &rd_req->rd_task; 344 } 345 346 /* rd_get_sg_table(): 347 * 348 * 349 */ 350 static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page) 351 { 352 u32 i; 353 struct rd_dev_sg_table *sg_table; 354 355 for (i = 0; i < rd_dev->sg_table_count; i++) { 356 sg_table = &rd_dev->sg_table_array[i]; 357 if ((sg_table->page_start_offset <= page) && 358 (sg_table->page_end_offset >= page)) 359 return sg_table; 360 } 361 362 printk(KERN_ERR "Unable to locate struct rd_dev_sg_table for page: %u\n", 363 page); 364 365 return NULL; 366 } 367 368 /* rd_MEMCPY_read(): 369 * 370 * 371 */ 372 static int rd_MEMCPY_read(struct rd_request *req) 373 { 374 struct se_task *task = &req->rd_task; 375 struct rd_dev *dev = req->rd_dev; 376 struct rd_dev_sg_table *table; 377 struct scatterlist *sg_d, *sg_s; 378 void *dst, *src; 379 u32 i = 0, j = 0, dst_offset = 0, src_offset = 0; 380 u32 length, page_end = 0, table_sg_end; 381 u32 rd_offset = req->rd_offset; 382 383 table = rd_get_sg_table(dev, req->rd_page); 384 if (!(table)) 385 return -1; 386 387 table_sg_end = (table->page_end_offset - req->rd_page); 388 sg_d = task->task_sg; 389 sg_s = &table->sg_table[req->rd_page - table->page_start_offset]; 390 #ifdef DEBUG_RAMDISK_MCP 391 printk(KERN_INFO "RD[%u]: Read LBA: %llu, Size: %u Page: %u, Offset:" 392 " %u\n", dev->rd_dev_id, task->task_lba, req->rd_size, 393 req->rd_page, req->rd_offset); 394 #endif 395 src_offset = rd_offset; 396 397 while (req->rd_size) { 398 if ((sg_d[i].length - dst_offset) < 399 (sg_s[j].length - src_offset)) { 400 length = (sg_d[i].length - dst_offset); 401 #ifdef DEBUG_RAMDISK_MCP 402 printk(KERN_INFO "Step 1 - sg_d[%d]: %p length: %d" 403 " offset: %u sg_s[%d].length: %u\n", i, 404 &sg_d[i], sg_d[i].length, sg_d[i].offset, j, 405 sg_s[j].length); 406 printk(KERN_INFO "Step 1 - length: %u dst_offset: %u" 407 " src_offset: %u\n", length, dst_offset, 408 src_offset); 409 #endif 410 if (length > req->rd_size) 411 length = req->rd_size; 412 413 dst = sg_virt(&sg_d[i++]) + dst_offset; 414 if (!dst) 415 BUG(); 416 417 src = sg_virt(&sg_s[j]) + src_offset; 418 if (!src) 419 BUG(); 420 421 dst_offset = 0; 422 src_offset = length; 423 page_end = 0; 424 } else { 425 length = (sg_s[j].length - src_offset); 426 #ifdef DEBUG_RAMDISK_MCP 427 printk(KERN_INFO "Step 2 - sg_d[%d]: %p length: %d" 428 " offset: %u sg_s[%d].length: %u\n", i, 429 &sg_d[i], sg_d[i].length, sg_d[i].offset, 430 j, sg_s[j].length); 431 printk(KERN_INFO "Step 2 - length: %u dst_offset: %u" 432 " src_offset: %u\n", length, dst_offset, 433 src_offset); 434 #endif 435 if (length > req->rd_size) 436 length = req->rd_size; 437 438 dst = sg_virt(&sg_d[i]) + dst_offset; 439 if (!dst) 440 BUG(); 441 442 if (sg_d[i].length == length) { 443 i++; 444 dst_offset = 0; 445 } else 446 dst_offset = length; 447 448 src = sg_virt(&sg_s[j++]) + src_offset; 449 if (!src) 450 BUG(); 451 452 src_offset = 0; 453 page_end = 1; 454 } 455 456 memcpy(dst, src, length); 457 458 #ifdef DEBUG_RAMDISK_MCP 459 printk(KERN_INFO "page: %u, remaining size: %u, length: %u," 460 " i: %u, j: %u\n", req->rd_page, 461 (req->rd_size - length), length, i, j); 462 #endif 463 req->rd_size -= length; 464 if (!(req->rd_size)) 465 return 0; 466 467 if (!page_end) 468 continue; 469 470 if (++req->rd_page <= table->page_end_offset) { 471 #ifdef DEBUG_RAMDISK_MCP 472 printk(KERN_INFO "page: %u in same page table\n", 473 req->rd_page); 474 #endif 475 continue; 476 } 477 #ifdef DEBUG_RAMDISK_MCP 478 printk(KERN_INFO "getting new page table for page: %u\n", 479 req->rd_page); 480 #endif 481 table = rd_get_sg_table(dev, req->rd_page); 482 if (!(table)) 483 return -1; 484 485 sg_s = &table->sg_table[j = 0]; 486 } 487 488 return 0; 489 } 490 491 /* rd_MEMCPY_write(): 492 * 493 * 494 */ 495 static int rd_MEMCPY_write(struct rd_request *req) 496 { 497 struct se_task *task = &req->rd_task; 498 struct rd_dev *dev = req->rd_dev; 499 struct rd_dev_sg_table *table; 500 struct scatterlist *sg_d, *sg_s; 501 void *dst, *src; 502 u32 i = 0, j = 0, dst_offset = 0, src_offset = 0; 503 u32 length, page_end = 0, table_sg_end; 504 u32 rd_offset = req->rd_offset; 505 506 table = rd_get_sg_table(dev, req->rd_page); 507 if (!(table)) 508 return -1; 509 510 table_sg_end = (table->page_end_offset - req->rd_page); 511 sg_d = &table->sg_table[req->rd_page - table->page_start_offset]; 512 sg_s = task->task_sg; 513 #ifdef DEBUG_RAMDISK_MCP 514 printk(KERN_INFO "RD[%d] Write LBA: %llu, Size: %u, Page: %u," 515 " Offset: %u\n", dev->rd_dev_id, task->task_lba, req->rd_size, 516 req->rd_page, req->rd_offset); 517 #endif 518 dst_offset = rd_offset; 519 520 while (req->rd_size) { 521 if ((sg_s[i].length - src_offset) < 522 (sg_d[j].length - dst_offset)) { 523 length = (sg_s[i].length - src_offset); 524 #ifdef DEBUG_RAMDISK_MCP 525 printk(KERN_INFO "Step 1 - sg_s[%d]: %p length: %d" 526 " offset: %d sg_d[%d].length: %u\n", i, 527 &sg_s[i], sg_s[i].length, sg_s[i].offset, 528 j, sg_d[j].length); 529 printk(KERN_INFO "Step 1 - length: %u src_offset: %u" 530 " dst_offset: %u\n", length, src_offset, 531 dst_offset); 532 #endif 533 if (length > req->rd_size) 534 length = req->rd_size; 535 536 src = sg_virt(&sg_s[i++]) + src_offset; 537 if (!src) 538 BUG(); 539 540 dst = sg_virt(&sg_d[j]) + dst_offset; 541 if (!dst) 542 BUG(); 543 544 src_offset = 0; 545 dst_offset = length; 546 page_end = 0; 547 } else { 548 length = (sg_d[j].length - dst_offset); 549 #ifdef DEBUG_RAMDISK_MCP 550 printk(KERN_INFO "Step 2 - sg_s[%d]: %p length: %d" 551 " offset: %d sg_d[%d].length: %u\n", i, 552 &sg_s[i], sg_s[i].length, sg_s[i].offset, 553 j, sg_d[j].length); 554 printk(KERN_INFO "Step 2 - length: %u src_offset: %u" 555 " dst_offset: %u\n", length, src_offset, 556 dst_offset); 557 #endif 558 if (length > req->rd_size) 559 length = req->rd_size; 560 561 src = sg_virt(&sg_s[i]) + src_offset; 562 if (!src) 563 BUG(); 564 565 if (sg_s[i].length == length) { 566 i++; 567 src_offset = 0; 568 } else 569 src_offset = length; 570 571 dst = sg_virt(&sg_d[j++]) + dst_offset; 572 if (!dst) 573 BUG(); 574 575 dst_offset = 0; 576 page_end = 1; 577 } 578 579 memcpy(dst, src, length); 580 581 #ifdef DEBUG_RAMDISK_MCP 582 printk(KERN_INFO "page: %u, remaining size: %u, length: %u," 583 " i: %u, j: %u\n", req->rd_page, 584 (req->rd_size - length), length, i, j); 585 #endif 586 req->rd_size -= length; 587 if (!(req->rd_size)) 588 return 0; 589 590 if (!page_end) 591 continue; 592 593 if (++req->rd_page <= table->page_end_offset) { 594 #ifdef DEBUG_RAMDISK_MCP 595 printk(KERN_INFO "page: %u in same page table\n", 596 req->rd_page); 597 #endif 598 continue; 599 } 600 #ifdef DEBUG_RAMDISK_MCP 601 printk(KERN_INFO "getting new page table for page: %u\n", 602 req->rd_page); 603 #endif 604 table = rd_get_sg_table(dev, req->rd_page); 605 if (!(table)) 606 return -1; 607 608 sg_d = &table->sg_table[j = 0]; 609 } 610 611 return 0; 612 } 613 614 /* rd_MEMCPY_do_task(): (Part of se_subsystem_api_t template) 615 * 616 * 617 */ 618 static int rd_MEMCPY_do_task(struct se_task *task) 619 { 620 struct se_device *dev = task->se_dev; 621 struct rd_request *req = RD_REQ(task); 622 unsigned long long lba; 623 int ret; 624 625 req->rd_page = (task->task_lba * DEV_ATTRIB(dev)->block_size) / PAGE_SIZE; 626 lba = task->task_lba; 627 req->rd_offset = (do_div(lba, 628 (PAGE_SIZE / DEV_ATTRIB(dev)->block_size))) * 629 DEV_ATTRIB(dev)->block_size; 630 req->rd_size = task->task_size; 631 632 if (task->task_data_direction == DMA_FROM_DEVICE) 633 ret = rd_MEMCPY_read(req); 634 else 635 ret = rd_MEMCPY_write(req); 636 637 if (ret != 0) 638 return ret; 639 640 task->task_scsi_status = GOOD; 641 transport_complete_task(task, 1); 642 643 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 644 } 645 646 /* rd_DIRECT_with_offset(): 647 * 648 * 649 */ 650 static int rd_DIRECT_with_offset( 651 struct se_task *task, 652 struct list_head *se_mem_list, 653 u32 *se_mem_cnt, 654 u32 *task_offset) 655 { 656 struct rd_request *req = RD_REQ(task); 657 struct rd_dev *dev = req->rd_dev; 658 struct rd_dev_sg_table *table; 659 struct se_mem *se_mem; 660 struct scatterlist *sg_s; 661 u32 j = 0, set_offset = 1; 662 u32 get_next_table = 0, offset_length, table_sg_end; 663 664 table = rd_get_sg_table(dev, req->rd_page); 665 if (!(table)) 666 return -1; 667 668 table_sg_end = (table->page_end_offset - req->rd_page); 669 sg_s = &table->sg_table[req->rd_page - table->page_start_offset]; 670 #ifdef DEBUG_RAMDISK_DR 671 printk(KERN_INFO "%s DIRECT LBA: %llu, Size: %u Page: %u, Offset: %u\n", 672 (task->task_data_direction == DMA_TO_DEVICE) ? 673 "Write" : "Read", 674 task->task_lba, req->rd_size, req->rd_page, req->rd_offset); 675 #endif 676 while (req->rd_size) { 677 se_mem = kmem_cache_zalloc(se_mem_cache, GFP_KERNEL); 678 if (!(se_mem)) { 679 printk(KERN_ERR "Unable to allocate struct se_mem\n"); 680 return -1; 681 } 682 INIT_LIST_HEAD(&se_mem->se_list); 683 684 if (set_offset) { 685 offset_length = sg_s[j].length - req->rd_offset; 686 if (offset_length > req->rd_size) 687 offset_length = req->rd_size; 688 689 se_mem->se_page = sg_page(&sg_s[j++]); 690 se_mem->se_off = req->rd_offset; 691 se_mem->se_len = offset_length; 692 693 set_offset = 0; 694 get_next_table = (j > table_sg_end); 695 goto check_eot; 696 } 697 698 offset_length = (req->rd_size < req->rd_offset) ? 699 req->rd_size : req->rd_offset; 700 701 se_mem->se_page = sg_page(&sg_s[j]); 702 se_mem->se_len = offset_length; 703 704 set_offset = 1; 705 706 check_eot: 707 #ifdef DEBUG_RAMDISK_DR 708 printk(KERN_INFO "page: %u, size: %u, offset_length: %u, j: %u" 709 " se_mem: %p, se_page: %p se_off: %u se_len: %u\n", 710 req->rd_page, req->rd_size, offset_length, j, se_mem, 711 se_mem->se_page, se_mem->se_off, se_mem->se_len); 712 #endif 713 list_add_tail(&se_mem->se_list, se_mem_list); 714 (*se_mem_cnt)++; 715 716 req->rd_size -= offset_length; 717 if (!(req->rd_size)) 718 goto out; 719 720 if (!set_offset && !get_next_table) 721 continue; 722 723 if (++req->rd_page <= table->page_end_offset) { 724 #ifdef DEBUG_RAMDISK_DR 725 printk(KERN_INFO "page: %u in same page table\n", 726 req->rd_page); 727 #endif 728 continue; 729 } 730 #ifdef DEBUG_RAMDISK_DR 731 printk(KERN_INFO "getting new page table for page: %u\n", 732 req->rd_page); 733 #endif 734 table = rd_get_sg_table(dev, req->rd_page); 735 if (!(table)) 736 return -1; 737 738 sg_s = &table->sg_table[j = 0]; 739 } 740 741 out: 742 T_TASK(task->task_se_cmd)->t_tasks_se_num += *se_mem_cnt; 743 #ifdef DEBUG_RAMDISK_DR 744 printk(KERN_INFO "RD_DR - Allocated %u struct se_mem segments for task\n", 745 *se_mem_cnt); 746 #endif 747 return 0; 748 } 749 750 /* rd_DIRECT_without_offset(): 751 * 752 * 753 */ 754 static int rd_DIRECT_without_offset( 755 struct se_task *task, 756 struct list_head *se_mem_list, 757 u32 *se_mem_cnt, 758 u32 *task_offset) 759 { 760 struct rd_request *req = RD_REQ(task); 761 struct rd_dev *dev = req->rd_dev; 762 struct rd_dev_sg_table *table; 763 struct se_mem *se_mem; 764 struct scatterlist *sg_s; 765 u32 length, j = 0; 766 767 table = rd_get_sg_table(dev, req->rd_page); 768 if (!(table)) 769 return -1; 770 771 sg_s = &table->sg_table[req->rd_page - table->page_start_offset]; 772 #ifdef DEBUG_RAMDISK_DR 773 printk(KERN_INFO "%s DIRECT LBA: %llu, Size: %u, Page: %u\n", 774 (task->task_data_direction == DMA_TO_DEVICE) ? 775 "Write" : "Read", 776 task->task_lba, req->rd_size, req->rd_page); 777 #endif 778 while (req->rd_size) { 779 se_mem = kmem_cache_zalloc(se_mem_cache, GFP_KERNEL); 780 if (!(se_mem)) { 781 printk(KERN_ERR "Unable to allocate struct se_mem\n"); 782 return -1; 783 } 784 INIT_LIST_HEAD(&se_mem->se_list); 785 786 length = (req->rd_size < sg_s[j].length) ? 787 req->rd_size : sg_s[j].length; 788 789 se_mem->se_page = sg_page(&sg_s[j++]); 790 se_mem->se_len = length; 791 792 #ifdef DEBUG_RAMDISK_DR 793 printk(KERN_INFO "page: %u, size: %u, j: %u se_mem: %p," 794 " se_page: %p se_off: %u se_len: %u\n", req->rd_page, 795 req->rd_size, j, se_mem, se_mem->se_page, 796 se_mem->se_off, se_mem->se_len); 797 #endif 798 list_add_tail(&se_mem->se_list, se_mem_list); 799 (*se_mem_cnt)++; 800 801 req->rd_size -= length; 802 if (!(req->rd_size)) 803 goto out; 804 805 if (++req->rd_page <= table->page_end_offset) { 806 #ifdef DEBUG_RAMDISK_DR 807 printk("page: %u in same page table\n", 808 req->rd_page); 809 #endif 810 continue; 811 } 812 #ifdef DEBUG_RAMDISK_DR 813 printk(KERN_INFO "getting new page table for page: %u\n", 814 req->rd_page); 815 #endif 816 table = rd_get_sg_table(dev, req->rd_page); 817 if (!(table)) 818 return -1; 819 820 sg_s = &table->sg_table[j = 0]; 821 } 822 823 out: 824 T_TASK(task->task_se_cmd)->t_tasks_se_num += *se_mem_cnt; 825 #ifdef DEBUG_RAMDISK_DR 826 printk(KERN_INFO "RD_DR - Allocated %u struct se_mem segments for task\n", 827 *se_mem_cnt); 828 #endif 829 return 0; 830 } 831 832 /* rd_DIRECT_do_se_mem_map(): 833 * 834 * 835 */ 836 static int rd_DIRECT_do_se_mem_map( 837 struct se_task *task, 838 struct list_head *se_mem_list, 839 void *in_mem, 840 struct se_mem *in_se_mem, 841 struct se_mem **out_se_mem, 842 u32 *se_mem_cnt, 843 u32 *task_offset_in) 844 { 845 struct se_cmd *cmd = task->task_se_cmd; 846 struct rd_request *req = RD_REQ(task); 847 u32 task_offset = *task_offset_in; 848 unsigned long long lba; 849 int ret; 850 851 req->rd_page = ((task->task_lba * DEV_ATTRIB(task->se_dev)->block_size) / 852 PAGE_SIZE); 853 lba = task->task_lba; 854 req->rd_offset = (do_div(lba, 855 (PAGE_SIZE / DEV_ATTRIB(task->se_dev)->block_size))) * 856 DEV_ATTRIB(task->se_dev)->block_size; 857 req->rd_size = task->task_size; 858 859 if (req->rd_offset) 860 ret = rd_DIRECT_with_offset(task, se_mem_list, se_mem_cnt, 861 task_offset_in); 862 else 863 ret = rd_DIRECT_without_offset(task, se_mem_list, se_mem_cnt, 864 task_offset_in); 865 866 if (ret < 0) 867 return ret; 868 869 if (CMD_TFO(cmd)->task_sg_chaining == 0) 870 return 0; 871 /* 872 * Currently prevent writers from multiple HW fabrics doing 873 * pci_map_sg() to RD_DR's internal scatterlist memory. 874 */ 875 if (cmd->data_direction == DMA_TO_DEVICE) { 876 printk(KERN_ERR "DMA_TO_DEVICE not supported for" 877 " RAMDISK_DR with task_sg_chaining=1\n"); 878 return -1; 879 } 880 /* 881 * Special case for if task_sg_chaining is enabled, then 882 * we setup struct se_task->task_sg[], as it will be used by 883 * transport_do_task_sg_chain() for creating chainged SGLs 884 * across multiple struct se_task->task_sg[]. 885 */ 886 if (!(transport_calc_sg_num(task, 887 list_entry(T_TASK(cmd)->t_mem_list->next, 888 struct se_mem, se_list), 889 task_offset))) 890 return -1; 891 892 return transport_map_mem_to_sg(task, se_mem_list, task->task_sg, 893 list_entry(T_TASK(cmd)->t_mem_list->next, 894 struct se_mem, se_list), 895 out_se_mem, se_mem_cnt, task_offset_in); 896 } 897 898 /* rd_DIRECT_do_task(): (Part of se_subsystem_api_t template) 899 * 900 * 901 */ 902 static int rd_DIRECT_do_task(struct se_task *task) 903 { 904 /* 905 * At this point the locally allocated RD tables have been mapped 906 * to struct se_mem elements in rd_DIRECT_do_se_mem_map(). 907 */ 908 task->task_scsi_status = GOOD; 909 transport_complete_task(task, 1); 910 911 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 912 } 913 914 /* rd_free_task(): (Part of se_subsystem_api_t template) 915 * 916 * 917 */ 918 static void rd_free_task(struct se_task *task) 919 { 920 kfree(RD_REQ(task)); 921 } 922 923 enum { 924 Opt_rd_pages, Opt_err 925 }; 926 927 static match_table_t tokens = { 928 {Opt_rd_pages, "rd_pages=%d"}, 929 {Opt_err, NULL} 930 }; 931 932 static ssize_t rd_set_configfs_dev_params( 933 struct se_hba *hba, 934 struct se_subsystem_dev *se_dev, 935 const char *page, 936 ssize_t count) 937 { 938 struct rd_dev *rd_dev = se_dev->se_dev_su_ptr; 939 char *orig, *ptr, *opts; 940 substring_t args[MAX_OPT_ARGS]; 941 int ret = 0, arg, token; 942 943 opts = kstrdup(page, GFP_KERNEL); 944 if (!opts) 945 return -ENOMEM; 946 947 orig = opts; 948 949 while ((ptr = strsep(&opts, ",")) != NULL) { 950 if (!*ptr) 951 continue; 952 953 token = match_token(ptr, tokens, args); 954 switch (token) { 955 case Opt_rd_pages: 956 match_int(args, &arg); 957 rd_dev->rd_page_count = arg; 958 printk(KERN_INFO "RAMDISK: Referencing Page" 959 " Count: %u\n", rd_dev->rd_page_count); 960 rd_dev->rd_flags |= RDF_HAS_PAGE_COUNT; 961 break; 962 default: 963 break; 964 } 965 } 966 967 kfree(orig); 968 return (!ret) ? count : ret; 969 } 970 971 static ssize_t rd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev) 972 { 973 struct rd_dev *rd_dev = se_dev->se_dev_su_ptr; 974 975 if (!(rd_dev->rd_flags & RDF_HAS_PAGE_COUNT)) { 976 printk(KERN_INFO "Missing rd_pages= parameter\n"); 977 return -1; 978 } 979 980 return 0; 981 } 982 983 static ssize_t rd_show_configfs_dev_params( 984 struct se_hba *hba, 985 struct se_subsystem_dev *se_dev, 986 char *b) 987 { 988 struct rd_dev *rd_dev = se_dev->se_dev_su_ptr; 989 ssize_t bl = sprintf(b, "TCM RamDisk ID: %u RamDisk Makeup: %s\n", 990 rd_dev->rd_dev_id, (rd_dev->rd_direct) ? 991 "rd_direct" : "rd_mcp"); 992 bl += sprintf(b + bl, " PAGES/PAGE_SIZE: %u*%lu" 993 " SG_table_count: %u\n", rd_dev->rd_page_count, 994 PAGE_SIZE, rd_dev->sg_table_count); 995 return bl; 996 } 997 998 /* rd_get_cdb(): (Part of se_subsystem_api_t template) 999 * 1000 * 1001 */ 1002 static unsigned char *rd_get_cdb(struct se_task *task) 1003 { 1004 struct rd_request *req = RD_REQ(task); 1005 1006 return req->rd_scsi_cdb; 1007 } 1008 1009 static u32 rd_get_device_rev(struct se_device *dev) 1010 { 1011 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ 1012 } 1013 1014 static u32 rd_get_device_type(struct se_device *dev) 1015 { 1016 return TYPE_DISK; 1017 } 1018 1019 static sector_t rd_get_blocks(struct se_device *dev) 1020 { 1021 struct rd_dev *rd_dev = dev->dev_ptr; 1022 unsigned long long blocks_long = ((rd_dev->rd_page_count * PAGE_SIZE) / 1023 DEV_ATTRIB(dev)->block_size) - 1; 1024 1025 return blocks_long; 1026 } 1027 1028 static struct se_subsystem_api rd_dr_template = { 1029 .name = "rd_dr", 1030 .transport_type = TRANSPORT_PLUGIN_VHBA_VDEV, 1031 .attach_hba = rd_attach_hba, 1032 .detach_hba = rd_detach_hba, 1033 .allocate_virtdevice = rd_DIRECT_allocate_virtdevice, 1034 .create_virtdevice = rd_DIRECT_create_virtdevice, 1035 .free_device = rd_free_device, 1036 .alloc_task = rd_alloc_task, 1037 .do_task = rd_DIRECT_do_task, 1038 .free_task = rd_free_task, 1039 .check_configfs_dev_params = rd_check_configfs_dev_params, 1040 .set_configfs_dev_params = rd_set_configfs_dev_params, 1041 .show_configfs_dev_params = rd_show_configfs_dev_params, 1042 .get_cdb = rd_get_cdb, 1043 .get_device_rev = rd_get_device_rev, 1044 .get_device_type = rd_get_device_type, 1045 .get_blocks = rd_get_blocks, 1046 .do_se_mem_map = rd_DIRECT_do_se_mem_map, 1047 }; 1048 1049 static struct se_subsystem_api rd_mcp_template = { 1050 .name = "rd_mcp", 1051 .transport_type = TRANSPORT_PLUGIN_VHBA_VDEV, 1052 .attach_hba = rd_attach_hba, 1053 .detach_hba = rd_detach_hba, 1054 .allocate_virtdevice = rd_MEMCPY_allocate_virtdevice, 1055 .create_virtdevice = rd_MEMCPY_create_virtdevice, 1056 .free_device = rd_free_device, 1057 .alloc_task = rd_alloc_task, 1058 .do_task = rd_MEMCPY_do_task, 1059 .free_task = rd_free_task, 1060 .check_configfs_dev_params = rd_check_configfs_dev_params, 1061 .set_configfs_dev_params = rd_set_configfs_dev_params, 1062 .show_configfs_dev_params = rd_show_configfs_dev_params, 1063 .get_cdb = rd_get_cdb, 1064 .get_device_rev = rd_get_device_rev, 1065 .get_device_type = rd_get_device_type, 1066 .get_blocks = rd_get_blocks, 1067 }; 1068 1069 int __init rd_module_init(void) 1070 { 1071 int ret; 1072 1073 ret = transport_subsystem_register(&rd_dr_template); 1074 if (ret < 0) 1075 return ret; 1076 1077 ret = transport_subsystem_register(&rd_mcp_template); 1078 if (ret < 0) { 1079 transport_subsystem_release(&rd_dr_template); 1080 return ret; 1081 } 1082 1083 return 0; 1084 } 1085 1086 void rd_module_exit(void) 1087 { 1088 transport_subsystem_release(&rd_dr_template); 1089 transport_subsystem_release(&rd_mcp_template); 1090 } 1091