1 /******************************************************************************* 2 * Filename: target_core_file.c 3 * 4 * This file contains the Storage Engine <-> FILEIO transport specific functions 5 * 6 * Copyright (c) 2005 PyX Technologies, Inc. 7 * Copyright (c) 2005-2006 SBE, Inc. All Rights Reserved. 8 * Copyright (c) 2007-2010 Rising Tide Systems 9 * Copyright (c) 2008-2010 Linux-iSCSI.org 10 * 11 * Nicholas A. Bellinger <nab@kernel.org> 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or 16 * (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 26 * 27 ******************************************************************************/ 28 29 #include <linux/version.h> 30 #include <linux/string.h> 31 #include <linux/parser.h> 32 #include <linux/timer.h> 33 #include <linux/blkdev.h> 34 #include <linux/slab.h> 35 #include <linux/spinlock.h> 36 #include <scsi/scsi.h> 37 #include <scsi/scsi_host.h> 38 39 #include <target/target_core_base.h> 40 #include <target/target_core_device.h> 41 #include <target/target_core_transport.h> 42 43 #include "target_core_file.h" 44 45 static struct se_subsystem_api fileio_template; 46 47 /* fd_attach_hba(): (Part of se_subsystem_api_t template) 48 * 49 * 50 */ 51 static int fd_attach_hba(struct se_hba *hba, u32 host_id) 52 { 53 struct fd_host *fd_host; 54 55 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL); 56 if (!fd_host) { 57 pr_err("Unable to allocate memory for struct fd_host\n"); 58 return -ENOMEM; 59 } 60 61 fd_host->fd_host_id = host_id; 62 63 hba->hba_ptr = fd_host; 64 65 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic" 66 " Target Core Stack %s\n", hba->hba_id, FD_VERSION, 67 TARGET_CORE_MOD_VERSION); 68 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic" 69 " MaxSectors: %u\n", 70 hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS); 71 72 return 0; 73 } 74 75 static void fd_detach_hba(struct se_hba *hba) 76 { 77 struct fd_host *fd_host = hba->hba_ptr; 78 79 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic" 80 " Target Core\n", hba->hba_id, fd_host->fd_host_id); 81 82 kfree(fd_host); 83 hba->hba_ptr = NULL; 84 } 85 86 static void *fd_allocate_virtdevice(struct se_hba *hba, const char *name) 87 { 88 struct fd_dev *fd_dev; 89 struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr; 90 91 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL); 92 if (!fd_dev) { 93 pr_err("Unable to allocate memory for struct fd_dev\n"); 94 return NULL; 95 } 96 97 fd_dev->fd_host = fd_host; 98 99 pr_debug("FILEIO: Allocated fd_dev for %p\n", name); 100 101 return fd_dev; 102 } 103 104 /* fd_create_virtdevice(): (Part of se_subsystem_api_t template) 105 * 106 * 107 */ 108 static struct se_device *fd_create_virtdevice( 109 struct se_hba *hba, 110 struct se_subsystem_dev *se_dev, 111 void *p) 112 { 113 char *dev_p = NULL; 114 struct se_device *dev; 115 struct se_dev_limits dev_limits; 116 struct queue_limits *limits; 117 struct fd_dev *fd_dev = (struct fd_dev *) p; 118 struct fd_host *fd_host = (struct fd_host *) hba->hba_ptr; 119 mm_segment_t old_fs; 120 struct file *file; 121 struct inode *inode = NULL; 122 int dev_flags = 0, flags, ret = -EINVAL; 123 124 memset(&dev_limits, 0, sizeof(struct se_dev_limits)); 125 126 old_fs = get_fs(); 127 set_fs(get_ds()); 128 dev_p = getname(fd_dev->fd_dev_name); 129 set_fs(old_fs); 130 131 if (IS_ERR(dev_p)) { 132 pr_err("getname(%s) failed: %lu\n", 133 fd_dev->fd_dev_name, IS_ERR(dev_p)); 134 ret = PTR_ERR(dev_p); 135 goto fail; 136 } 137 #if 0 138 if (di->no_create_file) 139 flags = O_RDWR | O_LARGEFILE; 140 else 141 flags = O_RDWR | O_CREAT | O_LARGEFILE; 142 #else 143 flags = O_RDWR | O_CREAT | O_LARGEFILE; 144 #endif 145 /* flags |= O_DIRECT; */ 146 /* 147 * If fd_buffered_io=1 has not been set explicitly (the default), 148 * use O_SYNC to force FILEIO writes to disk. 149 */ 150 if (!(fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO)) 151 flags |= O_SYNC; 152 153 file = filp_open(dev_p, flags, 0600); 154 if (IS_ERR(file)) { 155 pr_err("filp_open(%s) failed\n", dev_p); 156 ret = PTR_ERR(file); 157 goto fail; 158 } 159 if (!file || !file->f_dentry) { 160 pr_err("filp_open(%s) failed\n", dev_p); 161 goto fail; 162 } 163 fd_dev->fd_file = file; 164 /* 165 * If using a block backend with this struct file, we extract 166 * fd_dev->fd_[block,dev]_size from struct block_device. 167 * 168 * Otherwise, we use the passed fd_size= from configfs 169 */ 170 inode = file->f_mapping->host; 171 if (S_ISBLK(inode->i_mode)) { 172 struct request_queue *q; 173 /* 174 * Setup the local scope queue_limits from struct request_queue->limits 175 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits. 176 */ 177 q = bdev_get_queue(inode->i_bdev); 178 limits = &dev_limits.limits; 179 limits->logical_block_size = bdev_logical_block_size(inode->i_bdev); 180 limits->max_hw_sectors = queue_max_hw_sectors(q); 181 limits->max_sectors = queue_max_sectors(q); 182 /* 183 * Determine the number of bytes from i_size_read() minus 184 * one (1) logical sector from underlying struct block_device 185 */ 186 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev); 187 fd_dev->fd_dev_size = (i_size_read(file->f_mapping->host) - 188 fd_dev->fd_block_size); 189 190 pr_debug("FILEIO: Using size: %llu bytes from struct" 191 " block_device blocks: %llu logical_block_size: %d\n", 192 fd_dev->fd_dev_size, 193 div_u64(fd_dev->fd_dev_size, fd_dev->fd_block_size), 194 fd_dev->fd_block_size); 195 } else { 196 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) { 197 pr_err("FILEIO: Missing fd_dev_size=" 198 " parameter, and no backing struct" 199 " block_device\n"); 200 goto fail; 201 } 202 203 limits = &dev_limits.limits; 204 limits->logical_block_size = FD_BLOCKSIZE; 205 limits->max_hw_sectors = FD_MAX_SECTORS; 206 limits->max_sectors = FD_MAX_SECTORS; 207 fd_dev->fd_block_size = FD_BLOCKSIZE; 208 } 209 210 dev_limits.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH; 211 dev_limits.queue_depth = FD_DEVICE_QUEUE_DEPTH; 212 213 dev = transport_add_device_to_core_hba(hba, &fileio_template, 214 se_dev, dev_flags, fd_dev, 215 &dev_limits, "FILEIO", FD_VERSION); 216 if (!dev) 217 goto fail; 218 219 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++; 220 fd_dev->fd_queue_depth = dev->queue_depth; 221 222 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s," 223 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id, 224 fd_dev->fd_dev_name, fd_dev->fd_dev_size); 225 226 putname(dev_p); 227 return dev; 228 fail: 229 if (fd_dev->fd_file) { 230 filp_close(fd_dev->fd_file, NULL); 231 fd_dev->fd_file = NULL; 232 } 233 putname(dev_p); 234 return ERR_PTR(ret); 235 } 236 237 /* fd_free_device(): (Part of se_subsystem_api_t template) 238 * 239 * 240 */ 241 static void fd_free_device(void *p) 242 { 243 struct fd_dev *fd_dev = (struct fd_dev *) p; 244 245 if (fd_dev->fd_file) { 246 filp_close(fd_dev->fd_file, NULL); 247 fd_dev->fd_file = NULL; 248 } 249 250 kfree(fd_dev); 251 } 252 253 static inline struct fd_request *FILE_REQ(struct se_task *task) 254 { 255 return container_of(task, struct fd_request, fd_task); 256 } 257 258 259 static struct se_task * 260 fd_alloc_task(unsigned char *cdb) 261 { 262 struct fd_request *fd_req; 263 264 fd_req = kzalloc(sizeof(struct fd_request), GFP_KERNEL); 265 if (!fd_req) { 266 pr_err("Unable to allocate struct fd_request\n"); 267 return NULL; 268 } 269 270 return &fd_req->fd_task; 271 } 272 273 static int fd_do_readv(struct se_task *task) 274 { 275 struct fd_request *req = FILE_REQ(task); 276 struct fd_dev *dev = req->fd_task.se_dev->dev_ptr; 277 struct file *fd = dev->fd_file; 278 struct scatterlist *sg = task->task_sg; 279 struct iovec *iov; 280 mm_segment_t old_fs; 281 loff_t pos = (task->task_lba * 282 task->se_dev->se_sub_dev->se_dev_attrib.block_size); 283 int ret = 0, i; 284 285 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL); 286 if (!iov) { 287 pr_err("Unable to allocate fd_do_readv iov[]\n"); 288 return -ENOMEM; 289 } 290 291 for (i = 0; i < task->task_sg_nents; i++) { 292 iov[i].iov_len = sg[i].length; 293 iov[i].iov_base = sg_virt(&sg[i]); 294 } 295 296 old_fs = get_fs(); 297 set_fs(get_ds()); 298 ret = vfs_readv(fd, &iov[0], task->task_sg_nents, &pos); 299 set_fs(old_fs); 300 301 kfree(iov); 302 /* 303 * Return zeros and GOOD status even if the READ did not return 304 * the expected virt_size for struct file w/o a backing struct 305 * block_device. 306 */ 307 if (S_ISBLK(fd->f_dentry->d_inode->i_mode)) { 308 if (ret < 0 || ret != task->task_size) { 309 pr_err("vfs_readv() returned %d," 310 " expecting %d for S_ISBLK\n", ret, 311 (int)task->task_size); 312 return (ret < 0 ? ret : -EINVAL); 313 } 314 } else { 315 if (ret < 0) { 316 pr_err("vfs_readv() returned %d for non" 317 " S_ISBLK\n", ret); 318 return ret; 319 } 320 } 321 322 return 1; 323 } 324 325 static int fd_do_writev(struct se_task *task) 326 { 327 struct fd_request *req = FILE_REQ(task); 328 struct fd_dev *dev = req->fd_task.se_dev->dev_ptr; 329 struct file *fd = dev->fd_file; 330 struct scatterlist *sg = task->task_sg; 331 struct iovec *iov; 332 mm_segment_t old_fs; 333 loff_t pos = (task->task_lba * 334 task->se_dev->se_sub_dev->se_dev_attrib.block_size); 335 int ret, i = 0; 336 337 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL); 338 if (!iov) { 339 pr_err("Unable to allocate fd_do_writev iov[]\n"); 340 return -ENOMEM; 341 } 342 343 for (i = 0; i < task->task_sg_nents; i++) { 344 iov[i].iov_len = sg[i].length; 345 iov[i].iov_base = sg_virt(&sg[i]); 346 } 347 348 old_fs = get_fs(); 349 set_fs(get_ds()); 350 ret = vfs_writev(fd, &iov[0], task->task_sg_nents, &pos); 351 set_fs(old_fs); 352 353 kfree(iov); 354 355 if (ret < 0 || ret != task->task_size) { 356 pr_err("vfs_writev() returned %d\n", ret); 357 return (ret < 0 ? ret : -EINVAL); 358 } 359 360 return 1; 361 } 362 363 static void fd_emulate_sync_cache(struct se_task *task) 364 { 365 struct se_cmd *cmd = task->task_se_cmd; 366 struct se_device *dev = cmd->se_dev; 367 struct fd_dev *fd_dev = dev->dev_ptr; 368 int immed = (cmd->t_task_cdb[1] & 0x2); 369 loff_t start, end; 370 int ret; 371 372 /* 373 * If the Immediate bit is set, queue up the GOOD response 374 * for this SYNCHRONIZE_CACHE op 375 */ 376 if (immed) 377 transport_complete_sync_cache(cmd, 1); 378 379 /* 380 * Determine if we will be flushing the entire device. 381 */ 382 if (cmd->t_task_lba == 0 && cmd->data_length == 0) { 383 start = 0; 384 end = LLONG_MAX; 385 } else { 386 start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size; 387 if (cmd->data_length) 388 end = start + cmd->data_length; 389 else 390 end = LLONG_MAX; 391 } 392 393 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1); 394 if (ret != 0) 395 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret); 396 397 if (!immed) 398 transport_complete_sync_cache(cmd, ret == 0); 399 } 400 401 /* 402 * Tell TCM Core that we are capable of WriteCache emulation for 403 * an underlying struct se_device. 404 */ 405 static int fd_emulated_write_cache(struct se_device *dev) 406 { 407 return 1; 408 } 409 410 static int fd_emulated_dpo(struct se_device *dev) 411 { 412 return 0; 413 } 414 /* 415 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs 416 * for TYPE_DISK. 417 */ 418 static int fd_emulated_fua_write(struct se_device *dev) 419 { 420 return 1; 421 } 422 423 static int fd_emulated_fua_read(struct se_device *dev) 424 { 425 return 0; 426 } 427 428 /* 429 * WRITE Force Unit Access (FUA) emulation on a per struct se_task 430 * LBA range basis.. 431 */ 432 static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task) 433 { 434 struct se_device *dev = cmd->se_dev; 435 struct fd_dev *fd_dev = dev->dev_ptr; 436 loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size; 437 loff_t end = start + task->task_size; 438 int ret; 439 440 pr_debug("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n", 441 task->task_lba, task->task_size); 442 443 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1); 444 if (ret != 0) 445 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret); 446 } 447 448 static int fd_do_task(struct se_task *task) 449 { 450 struct se_cmd *cmd = task->task_se_cmd; 451 struct se_device *dev = cmd->se_dev; 452 int ret = 0; 453 454 /* 455 * Call vectorized fileio functions to map struct scatterlist 456 * physical memory addresses to struct iovec virtual memory. 457 */ 458 if (task->task_data_direction == DMA_FROM_DEVICE) { 459 ret = fd_do_readv(task); 460 } else { 461 ret = fd_do_writev(task); 462 463 if (ret > 0 && 464 dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0 && 465 dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 && 466 cmd->t_tasks_fua) { 467 /* 468 * We might need to be a bit smarter here 469 * and return some sense data to let the initiator 470 * know the FUA WRITE cache sync failed..? 471 */ 472 fd_emulate_write_fua(cmd, task); 473 } 474 475 } 476 477 if (ret < 0) 478 return ret; 479 if (ret) { 480 task->task_scsi_status = GOOD; 481 transport_complete_task(task, 1); 482 } 483 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 484 } 485 486 /* fd_free_task(): (Part of se_subsystem_api_t template) 487 * 488 * 489 */ 490 static void fd_free_task(struct se_task *task) 491 { 492 struct fd_request *req = FILE_REQ(task); 493 494 kfree(req); 495 } 496 497 enum { 498 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err 499 }; 500 501 static match_table_t tokens = { 502 {Opt_fd_dev_name, "fd_dev_name=%s"}, 503 {Opt_fd_dev_size, "fd_dev_size=%s"}, 504 {Opt_fd_buffered_io, "fd_buffered_io=%d"}, 505 {Opt_err, NULL} 506 }; 507 508 static ssize_t fd_set_configfs_dev_params( 509 struct se_hba *hba, 510 struct se_subsystem_dev *se_dev, 511 const char *page, ssize_t count) 512 { 513 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr; 514 char *orig, *ptr, *arg_p, *opts; 515 substring_t args[MAX_OPT_ARGS]; 516 int ret = 0, arg, token; 517 518 opts = kstrdup(page, GFP_KERNEL); 519 if (!opts) 520 return -ENOMEM; 521 522 orig = opts; 523 524 while ((ptr = strsep(&opts, ",")) != NULL) { 525 if (!*ptr) 526 continue; 527 528 token = match_token(ptr, tokens, args); 529 switch (token) { 530 case Opt_fd_dev_name: 531 arg_p = match_strdup(&args[0]); 532 if (!arg_p) { 533 ret = -ENOMEM; 534 break; 535 } 536 snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME, 537 "%s", arg_p); 538 kfree(arg_p); 539 pr_debug("FILEIO: Referencing Path: %s\n", 540 fd_dev->fd_dev_name); 541 fd_dev->fbd_flags |= FBDF_HAS_PATH; 542 break; 543 case Opt_fd_dev_size: 544 arg_p = match_strdup(&args[0]); 545 if (!arg_p) { 546 ret = -ENOMEM; 547 break; 548 } 549 ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size); 550 kfree(arg_p); 551 if (ret < 0) { 552 pr_err("strict_strtoull() failed for" 553 " fd_dev_size=\n"); 554 goto out; 555 } 556 pr_debug("FILEIO: Referencing Size: %llu" 557 " bytes\n", fd_dev->fd_dev_size); 558 fd_dev->fbd_flags |= FBDF_HAS_SIZE; 559 break; 560 case Opt_fd_buffered_io: 561 match_int(args, &arg); 562 if (arg != 1) { 563 pr_err("bogus fd_buffered_io=%d value\n", arg); 564 ret = -EINVAL; 565 goto out; 566 } 567 568 pr_debug("FILEIO: Using buffered I/O" 569 " operations for struct fd_dev\n"); 570 571 fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO; 572 break; 573 default: 574 break; 575 } 576 } 577 578 out: 579 kfree(orig); 580 return (!ret) ? count : ret; 581 } 582 583 static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev) 584 { 585 struct fd_dev *fd_dev = (struct fd_dev *) se_dev->se_dev_su_ptr; 586 587 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) { 588 pr_err("Missing fd_dev_name=\n"); 589 return -EINVAL; 590 } 591 592 return 0; 593 } 594 595 static ssize_t fd_show_configfs_dev_params( 596 struct se_hba *hba, 597 struct se_subsystem_dev *se_dev, 598 char *b) 599 { 600 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr; 601 ssize_t bl = 0; 602 603 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id); 604 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s\n", 605 fd_dev->fd_dev_name, fd_dev->fd_dev_size, 606 (fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO) ? 607 "Buffered" : "Synchronous"); 608 return bl; 609 } 610 611 /* fd_get_cdb(): (Part of se_subsystem_api_t template) 612 * 613 * 614 */ 615 static unsigned char *fd_get_cdb(struct se_task *task) 616 { 617 struct fd_request *req = FILE_REQ(task); 618 619 return req->fd_scsi_cdb; 620 } 621 622 /* fd_get_device_rev(): (Part of se_subsystem_api_t template) 623 * 624 * 625 */ 626 static u32 fd_get_device_rev(struct se_device *dev) 627 { 628 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ 629 } 630 631 /* fd_get_device_type(): (Part of se_subsystem_api_t template) 632 * 633 * 634 */ 635 static u32 fd_get_device_type(struct se_device *dev) 636 { 637 return TYPE_DISK; 638 } 639 640 static sector_t fd_get_blocks(struct se_device *dev) 641 { 642 struct fd_dev *fd_dev = dev->dev_ptr; 643 unsigned long long blocks_long = div_u64(fd_dev->fd_dev_size, 644 dev->se_sub_dev->se_dev_attrib.block_size); 645 646 return blocks_long; 647 } 648 649 static struct se_subsystem_api fileio_template = { 650 .name = "fileio", 651 .owner = THIS_MODULE, 652 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 653 .attach_hba = fd_attach_hba, 654 .detach_hba = fd_detach_hba, 655 .allocate_virtdevice = fd_allocate_virtdevice, 656 .create_virtdevice = fd_create_virtdevice, 657 .free_device = fd_free_device, 658 .dpo_emulated = fd_emulated_dpo, 659 .fua_write_emulated = fd_emulated_fua_write, 660 .fua_read_emulated = fd_emulated_fua_read, 661 .write_cache_emulated = fd_emulated_write_cache, 662 .alloc_task = fd_alloc_task, 663 .do_task = fd_do_task, 664 .do_sync_cache = fd_emulate_sync_cache, 665 .free_task = fd_free_task, 666 .check_configfs_dev_params = fd_check_configfs_dev_params, 667 .set_configfs_dev_params = fd_set_configfs_dev_params, 668 .show_configfs_dev_params = fd_show_configfs_dev_params, 669 .get_cdb = fd_get_cdb, 670 .get_device_rev = fd_get_device_rev, 671 .get_device_type = fd_get_device_type, 672 .get_blocks = fd_get_blocks, 673 }; 674 675 static int __init fileio_module_init(void) 676 { 677 return transport_subsystem_register(&fileio_template); 678 } 679 680 static void fileio_module_exit(void) 681 { 682 transport_subsystem_release(&fileio_template); 683 } 684 685 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin"); 686 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 687 MODULE_LICENSE("GPL"); 688 689 module_init(fileio_module_init); 690 module_exit(fileio_module_exit); 691