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/string.h> 30 #include <linux/parser.h> 31 #include <linux/timer.h> 32 #include <linux/blkdev.h> 33 #include <linux/slab.h> 34 #include <linux/spinlock.h> 35 #include <linux/module.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 se_device *se_dev = req->fd_task.task_se_cmd->se_dev; 277 struct fd_dev *dev = se_dev->dev_ptr; 278 struct file *fd = dev->fd_file; 279 struct scatterlist *sg = task->task_sg; 280 struct iovec *iov; 281 mm_segment_t old_fs; 282 loff_t pos = (task->task_lba * 283 se_dev->se_sub_dev->se_dev_attrib.block_size); 284 int ret = 0, i; 285 286 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL); 287 if (!iov) { 288 pr_err("Unable to allocate fd_do_readv iov[]\n"); 289 return -ENOMEM; 290 } 291 292 for (i = 0; i < task->task_sg_nents; i++) { 293 iov[i].iov_len = sg[i].length; 294 iov[i].iov_base = sg_virt(&sg[i]); 295 } 296 297 old_fs = get_fs(); 298 set_fs(get_ds()); 299 ret = vfs_readv(fd, &iov[0], task->task_sg_nents, &pos); 300 set_fs(old_fs); 301 302 kfree(iov); 303 /* 304 * Return zeros and GOOD status even if the READ did not return 305 * the expected virt_size for struct file w/o a backing struct 306 * block_device. 307 */ 308 if (S_ISBLK(fd->f_dentry->d_inode->i_mode)) { 309 if (ret < 0 || ret != task->task_size) { 310 pr_err("vfs_readv() returned %d," 311 " expecting %d for S_ISBLK\n", ret, 312 (int)task->task_size); 313 return (ret < 0 ? ret : -EINVAL); 314 } 315 } else { 316 if (ret < 0) { 317 pr_err("vfs_readv() returned %d for non" 318 " S_ISBLK\n", ret); 319 return ret; 320 } 321 } 322 323 return 1; 324 } 325 326 static int fd_do_writev(struct se_task *task) 327 { 328 struct fd_request *req = FILE_REQ(task); 329 struct se_device *se_dev = req->fd_task.task_se_cmd->se_dev; 330 struct fd_dev *dev = se_dev->dev_ptr; 331 struct file *fd = dev->fd_file; 332 struct scatterlist *sg = task->task_sg; 333 struct iovec *iov; 334 mm_segment_t old_fs; 335 loff_t pos = (task->task_lba * 336 se_dev->se_sub_dev->se_dev_attrib.block_size); 337 int ret, i = 0; 338 339 iov = kzalloc(sizeof(struct iovec) * task->task_sg_nents, GFP_KERNEL); 340 if (!iov) { 341 pr_err("Unable to allocate fd_do_writev iov[]\n"); 342 return -ENOMEM; 343 } 344 345 for (i = 0; i < task->task_sg_nents; i++) { 346 iov[i].iov_len = sg[i].length; 347 iov[i].iov_base = sg_virt(&sg[i]); 348 } 349 350 old_fs = get_fs(); 351 set_fs(get_ds()); 352 ret = vfs_writev(fd, &iov[0], task->task_sg_nents, &pos); 353 set_fs(old_fs); 354 355 kfree(iov); 356 357 if (ret < 0 || ret != task->task_size) { 358 pr_err("vfs_writev() returned %d\n", ret); 359 return (ret < 0 ? ret : -EINVAL); 360 } 361 362 return 1; 363 } 364 365 static void fd_emulate_sync_cache(struct se_task *task) 366 { 367 struct se_cmd *cmd = task->task_se_cmd; 368 struct se_device *dev = cmd->se_dev; 369 struct fd_dev *fd_dev = dev->dev_ptr; 370 int immed = (cmd->t_task_cdb[1] & 0x2); 371 loff_t start, end; 372 int ret; 373 374 /* 375 * If the Immediate bit is set, queue up the GOOD response 376 * for this SYNCHRONIZE_CACHE op 377 */ 378 if (immed) 379 transport_complete_sync_cache(cmd, 1); 380 381 /* 382 * Determine if we will be flushing the entire device. 383 */ 384 if (cmd->t_task_lba == 0 && cmd->data_length == 0) { 385 start = 0; 386 end = LLONG_MAX; 387 } else { 388 start = cmd->t_task_lba * dev->se_sub_dev->se_dev_attrib.block_size; 389 if (cmd->data_length) 390 end = start + cmd->data_length; 391 else 392 end = LLONG_MAX; 393 } 394 395 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1); 396 if (ret != 0) 397 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret); 398 399 if (!immed) 400 transport_complete_sync_cache(cmd, ret == 0); 401 } 402 403 /* 404 * WRITE Force Unit Access (FUA) emulation on a per struct se_task 405 * LBA range basis.. 406 */ 407 static void fd_emulate_write_fua(struct se_cmd *cmd, struct se_task *task) 408 { 409 struct se_device *dev = cmd->se_dev; 410 struct fd_dev *fd_dev = dev->dev_ptr; 411 loff_t start = task->task_lba * dev->se_sub_dev->se_dev_attrib.block_size; 412 loff_t end = start + task->task_size; 413 int ret; 414 415 pr_debug("FILEIO: FUA WRITE LBA: %llu, bytes: %u\n", 416 task->task_lba, task->task_size); 417 418 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1); 419 if (ret != 0) 420 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret); 421 } 422 423 static int fd_do_task(struct se_task *task) 424 { 425 struct se_cmd *cmd = task->task_se_cmd; 426 struct se_device *dev = cmd->se_dev; 427 int ret = 0; 428 429 /* 430 * Call vectorized fileio functions to map struct scatterlist 431 * physical memory addresses to struct iovec virtual memory. 432 */ 433 if (task->task_data_direction == DMA_FROM_DEVICE) { 434 ret = fd_do_readv(task); 435 } else { 436 ret = fd_do_writev(task); 437 438 if (ret > 0 && 439 dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0 && 440 dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 && 441 cmd->t_tasks_fua) { 442 /* 443 * We might need to be a bit smarter here 444 * and return some sense data to let the initiator 445 * know the FUA WRITE cache sync failed..? 446 */ 447 fd_emulate_write_fua(cmd, task); 448 } 449 450 } 451 452 if (ret < 0) 453 return ret; 454 if (ret) { 455 task->task_scsi_status = GOOD; 456 transport_complete_task(task, 1); 457 } 458 return PYX_TRANSPORT_SENT_TO_TRANSPORT; 459 } 460 461 /* fd_free_task(): (Part of se_subsystem_api_t template) 462 * 463 * 464 */ 465 static void fd_free_task(struct se_task *task) 466 { 467 struct fd_request *req = FILE_REQ(task); 468 469 kfree(req); 470 } 471 472 enum { 473 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err 474 }; 475 476 static match_table_t tokens = { 477 {Opt_fd_dev_name, "fd_dev_name=%s"}, 478 {Opt_fd_dev_size, "fd_dev_size=%s"}, 479 {Opt_fd_buffered_io, "fd_buffered_io=%d"}, 480 {Opt_err, NULL} 481 }; 482 483 static ssize_t fd_set_configfs_dev_params( 484 struct se_hba *hba, 485 struct se_subsystem_dev *se_dev, 486 const char *page, ssize_t count) 487 { 488 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr; 489 char *orig, *ptr, *arg_p, *opts; 490 substring_t args[MAX_OPT_ARGS]; 491 int ret = 0, arg, token; 492 493 opts = kstrdup(page, GFP_KERNEL); 494 if (!opts) 495 return -ENOMEM; 496 497 orig = opts; 498 499 while ((ptr = strsep(&opts, ",")) != NULL) { 500 if (!*ptr) 501 continue; 502 503 token = match_token(ptr, tokens, args); 504 switch (token) { 505 case Opt_fd_dev_name: 506 arg_p = match_strdup(&args[0]); 507 if (!arg_p) { 508 ret = -ENOMEM; 509 break; 510 } 511 snprintf(fd_dev->fd_dev_name, FD_MAX_DEV_NAME, 512 "%s", arg_p); 513 kfree(arg_p); 514 pr_debug("FILEIO: Referencing Path: %s\n", 515 fd_dev->fd_dev_name); 516 fd_dev->fbd_flags |= FBDF_HAS_PATH; 517 break; 518 case Opt_fd_dev_size: 519 arg_p = match_strdup(&args[0]); 520 if (!arg_p) { 521 ret = -ENOMEM; 522 break; 523 } 524 ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size); 525 kfree(arg_p); 526 if (ret < 0) { 527 pr_err("strict_strtoull() failed for" 528 " fd_dev_size=\n"); 529 goto out; 530 } 531 pr_debug("FILEIO: Referencing Size: %llu" 532 " bytes\n", fd_dev->fd_dev_size); 533 fd_dev->fbd_flags |= FBDF_HAS_SIZE; 534 break; 535 case Opt_fd_buffered_io: 536 match_int(args, &arg); 537 if (arg != 1) { 538 pr_err("bogus fd_buffered_io=%d value\n", arg); 539 ret = -EINVAL; 540 goto out; 541 } 542 543 pr_debug("FILEIO: Using buffered I/O" 544 " operations for struct fd_dev\n"); 545 546 fd_dev->fbd_flags |= FDBD_USE_BUFFERED_IO; 547 break; 548 default: 549 break; 550 } 551 } 552 553 out: 554 kfree(orig); 555 return (!ret) ? count : ret; 556 } 557 558 static ssize_t fd_check_configfs_dev_params(struct se_hba *hba, struct se_subsystem_dev *se_dev) 559 { 560 struct fd_dev *fd_dev = (struct fd_dev *) se_dev->se_dev_su_ptr; 561 562 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) { 563 pr_err("Missing fd_dev_name=\n"); 564 return -EINVAL; 565 } 566 567 return 0; 568 } 569 570 static ssize_t fd_show_configfs_dev_params( 571 struct se_hba *hba, 572 struct se_subsystem_dev *se_dev, 573 char *b) 574 { 575 struct fd_dev *fd_dev = se_dev->se_dev_su_ptr; 576 ssize_t bl = 0; 577 578 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id); 579 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s\n", 580 fd_dev->fd_dev_name, fd_dev->fd_dev_size, 581 (fd_dev->fbd_flags & FDBD_USE_BUFFERED_IO) ? 582 "Buffered" : "Synchronous"); 583 return bl; 584 } 585 586 /* fd_get_device_rev(): (Part of se_subsystem_api_t template) 587 * 588 * 589 */ 590 static u32 fd_get_device_rev(struct se_device *dev) 591 { 592 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */ 593 } 594 595 /* fd_get_device_type(): (Part of se_subsystem_api_t template) 596 * 597 * 598 */ 599 static u32 fd_get_device_type(struct se_device *dev) 600 { 601 return TYPE_DISK; 602 } 603 604 static sector_t fd_get_blocks(struct se_device *dev) 605 { 606 struct fd_dev *fd_dev = dev->dev_ptr; 607 unsigned long long blocks_long = div_u64(fd_dev->fd_dev_size, 608 dev->se_sub_dev->se_dev_attrib.block_size); 609 610 return blocks_long; 611 } 612 613 static struct se_subsystem_api fileio_template = { 614 .name = "fileio", 615 .owner = THIS_MODULE, 616 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV, 617 .write_cache_emulated = 1, 618 .fua_write_emulated = 1, 619 .attach_hba = fd_attach_hba, 620 .detach_hba = fd_detach_hba, 621 .allocate_virtdevice = fd_allocate_virtdevice, 622 .create_virtdevice = fd_create_virtdevice, 623 .free_device = fd_free_device, 624 .alloc_task = fd_alloc_task, 625 .do_task = fd_do_task, 626 .do_sync_cache = fd_emulate_sync_cache, 627 .free_task = fd_free_task, 628 .check_configfs_dev_params = fd_check_configfs_dev_params, 629 .set_configfs_dev_params = fd_set_configfs_dev_params, 630 .show_configfs_dev_params = fd_show_configfs_dev_params, 631 .get_device_rev = fd_get_device_rev, 632 .get_device_type = fd_get_device_type, 633 .get_blocks = fd_get_blocks, 634 }; 635 636 static int __init fileio_module_init(void) 637 { 638 return transport_subsystem_register(&fileio_template); 639 } 640 641 static void fileio_module_exit(void) 642 { 643 transport_subsystem_release(&fileio_template); 644 } 645 646 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin"); 647 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 648 MODULE_LICENSE("GPL"); 649 650 module_init(fileio_module_init); 651 module_exit(fileio_module_exit); 652