1 /******************************************************************************* 2 * Filename: target_core_file.c 3 * 4 * This file contains the Storage Engine <-> FILEIO transport specific functions 5 * 6 * (c) Copyright 2005-2013 Datera, Inc. 7 * 8 * Nicholas A. Bellinger <nab@kernel.org> 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 23 * 24 ******************************************************************************/ 25 26 #include <linux/string.h> 27 #include <linux/parser.h> 28 #include <linux/timer.h> 29 #include <linux/blkdev.h> 30 #include <linux/slab.h> 31 #include <linux/spinlock.h> 32 #include <linux/module.h> 33 #include <linux/vmalloc.h> 34 #include <linux/falloc.h> 35 #include <linux/uio.h> 36 #include <scsi/scsi_proto.h> 37 #include <asm/unaligned.h> 38 39 #include <target/target_core_base.h> 40 #include <target/target_core_backend.h> 41 42 #include "target_core_file.h" 43 44 static inline struct fd_dev *FD_DEV(struct se_device *dev) 45 { 46 return container_of(dev, struct fd_dev, dev); 47 } 48 49 static int fd_attach_hba(struct se_hba *hba, u32 host_id) 50 { 51 struct fd_host *fd_host; 52 53 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL); 54 if (!fd_host) { 55 pr_err("Unable to allocate memory for struct fd_host\n"); 56 return -ENOMEM; 57 } 58 59 fd_host->fd_host_id = host_id; 60 61 hba->hba_ptr = fd_host; 62 63 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic" 64 " Target Core Stack %s\n", hba->hba_id, FD_VERSION, 65 TARGET_CORE_VERSION); 66 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n", 67 hba->hba_id, fd_host->fd_host_id); 68 69 return 0; 70 } 71 72 static void fd_detach_hba(struct se_hba *hba) 73 { 74 struct fd_host *fd_host = hba->hba_ptr; 75 76 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic" 77 " Target Core\n", hba->hba_id, fd_host->fd_host_id); 78 79 kfree(fd_host); 80 hba->hba_ptr = NULL; 81 } 82 83 static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name) 84 { 85 struct fd_dev *fd_dev; 86 struct fd_host *fd_host = hba->hba_ptr; 87 88 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL); 89 if (!fd_dev) { 90 pr_err("Unable to allocate memory for struct fd_dev\n"); 91 return NULL; 92 } 93 94 fd_dev->fd_host = fd_host; 95 96 pr_debug("FILEIO: Allocated fd_dev for %p\n", name); 97 98 return &fd_dev->dev; 99 } 100 101 static int fd_configure_device(struct se_device *dev) 102 { 103 struct fd_dev *fd_dev = FD_DEV(dev); 104 struct fd_host *fd_host = dev->se_hba->hba_ptr; 105 struct file *file; 106 struct inode *inode = NULL; 107 int flags, ret = -EINVAL; 108 109 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) { 110 pr_err("Missing fd_dev_name=\n"); 111 return -EINVAL; 112 } 113 114 /* 115 * Use O_DSYNC by default instead of O_SYNC to forgo syncing 116 * of pure timestamp updates. 117 */ 118 flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC; 119 120 /* 121 * Optionally allow fd_buffered_io=1 to be enabled for people 122 * who want use the fs buffer cache as an WriteCache mechanism. 123 * 124 * This means that in event of a hard failure, there is a risk 125 * of silent data-loss if the SCSI client has *not* performed a 126 * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE 127 * to write-out the entire device cache. 128 */ 129 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) { 130 pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n"); 131 flags &= ~O_DSYNC; 132 } 133 134 file = filp_open(fd_dev->fd_dev_name, flags, 0600); 135 if (IS_ERR(file)) { 136 pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name); 137 ret = PTR_ERR(file); 138 goto fail; 139 } 140 fd_dev->fd_file = file; 141 /* 142 * If using a block backend with this struct file, we extract 143 * fd_dev->fd_[block,dev]_size from struct block_device. 144 * 145 * Otherwise, we use the passed fd_size= from configfs 146 */ 147 inode = file->f_mapping->host; 148 if (S_ISBLK(inode->i_mode)) { 149 struct request_queue *q = bdev_get_queue(inode->i_bdev); 150 unsigned long long dev_size; 151 152 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev); 153 /* 154 * Determine the number of bytes from i_size_read() minus 155 * one (1) logical sector from underlying struct block_device 156 */ 157 dev_size = (i_size_read(file->f_mapping->host) - 158 fd_dev->fd_block_size); 159 160 pr_debug("FILEIO: Using size: %llu bytes from struct" 161 " block_device blocks: %llu logical_block_size: %d\n", 162 dev_size, div_u64(dev_size, fd_dev->fd_block_size), 163 fd_dev->fd_block_size); 164 165 if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) 166 pr_debug("IFILE: BLOCK Discard support available," 167 " disabled by default\n"); 168 /* 169 * Enable write same emulation for IBLOCK and use 0xFFFF as 170 * the smaller WRITE_SAME(10) only has a two-byte block count. 171 */ 172 dev->dev_attrib.max_write_same_len = 0xFFFF; 173 174 if (blk_queue_nonrot(q)) 175 dev->dev_attrib.is_nonrot = 1; 176 } else { 177 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) { 178 pr_err("FILEIO: Missing fd_dev_size=" 179 " parameter, and no backing struct" 180 " block_device\n"); 181 goto fail; 182 } 183 184 fd_dev->fd_block_size = FD_BLOCKSIZE; 185 /* 186 * Limit UNMAP emulation to 8k Number of LBAs (NoLB) 187 */ 188 dev->dev_attrib.max_unmap_lba_count = 0x2000; 189 /* 190 * Currently hardcoded to 1 in Linux/SCSI code.. 191 */ 192 dev->dev_attrib.max_unmap_block_desc_count = 1; 193 dev->dev_attrib.unmap_granularity = 1; 194 dev->dev_attrib.unmap_granularity_alignment = 0; 195 196 /* 197 * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB) 198 * based upon struct iovec limit for vfs_writev() 199 */ 200 dev->dev_attrib.max_write_same_len = 0x1000; 201 } 202 203 dev->dev_attrib.hw_block_size = fd_dev->fd_block_size; 204 dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES; 205 dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size; 206 dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH; 207 208 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) { 209 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1" 210 " with FDBD_HAS_BUFFERED_IO_WCE\n"); 211 dev->dev_attrib.emulate_write_cache = 1; 212 } 213 214 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++; 215 fd_dev->fd_queue_depth = dev->queue_depth; 216 217 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s," 218 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id, 219 fd_dev->fd_dev_name, fd_dev->fd_dev_size); 220 221 return 0; 222 fail: 223 if (fd_dev->fd_file) { 224 filp_close(fd_dev->fd_file, NULL); 225 fd_dev->fd_file = NULL; 226 } 227 return ret; 228 } 229 230 static void fd_dev_call_rcu(struct rcu_head *p) 231 { 232 struct se_device *dev = container_of(p, struct se_device, rcu_head); 233 struct fd_dev *fd_dev = FD_DEV(dev); 234 235 kfree(fd_dev); 236 } 237 238 static void fd_free_device(struct se_device *dev) 239 { 240 call_rcu(&dev->rcu_head, fd_dev_call_rcu); 241 } 242 243 static void fd_destroy_device(struct se_device *dev) 244 { 245 struct fd_dev *fd_dev = FD_DEV(dev); 246 247 if (fd_dev->fd_file) { 248 filp_close(fd_dev->fd_file, NULL); 249 fd_dev->fd_file = NULL; 250 } 251 } 252 253 struct target_core_file_cmd { 254 unsigned long len; 255 struct se_cmd *cmd; 256 struct kiocb iocb; 257 }; 258 259 static void cmd_rw_aio_complete(struct kiocb *iocb, long ret, long ret2) 260 { 261 struct target_core_file_cmd *cmd; 262 263 cmd = container_of(iocb, struct target_core_file_cmd, iocb); 264 265 if (ret != cmd->len) 266 target_complete_cmd(cmd->cmd, SAM_STAT_CHECK_CONDITION); 267 else 268 target_complete_cmd(cmd->cmd, SAM_STAT_GOOD); 269 270 kfree(cmd); 271 } 272 273 static sense_reason_t 274 fd_execute_rw_aio(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 275 enum dma_data_direction data_direction) 276 { 277 int is_write = !(data_direction == DMA_FROM_DEVICE); 278 struct se_device *dev = cmd->se_dev; 279 struct fd_dev *fd_dev = FD_DEV(dev); 280 struct file *file = fd_dev->fd_file; 281 struct target_core_file_cmd *aio_cmd; 282 struct iov_iter iter = {}; 283 struct scatterlist *sg; 284 struct bio_vec *bvec; 285 ssize_t len = 0; 286 int ret = 0, i; 287 288 aio_cmd = kmalloc(sizeof(struct target_core_file_cmd), GFP_KERNEL); 289 if (!aio_cmd) 290 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 291 292 bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL); 293 if (!bvec) { 294 kfree(aio_cmd); 295 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 296 } 297 298 for_each_sg(sgl, sg, sgl_nents, i) { 299 bvec[i].bv_page = sg_page(sg); 300 bvec[i].bv_len = sg->length; 301 bvec[i].bv_offset = sg->offset; 302 303 len += sg->length; 304 } 305 306 iov_iter_bvec(&iter, is_write, bvec, sgl_nents, len); 307 308 aio_cmd->cmd = cmd; 309 aio_cmd->len = len; 310 aio_cmd->iocb.ki_pos = cmd->t_task_lba * dev->dev_attrib.block_size; 311 aio_cmd->iocb.ki_filp = file; 312 aio_cmd->iocb.ki_complete = cmd_rw_aio_complete; 313 aio_cmd->iocb.ki_flags = IOCB_DIRECT; 314 315 if (is_write && (cmd->se_cmd_flags & SCF_FUA)) 316 aio_cmd->iocb.ki_flags |= IOCB_DSYNC; 317 318 if (is_write) 319 ret = call_write_iter(file, &aio_cmd->iocb, &iter); 320 else 321 ret = call_read_iter(file, &aio_cmd->iocb, &iter); 322 323 kfree(bvec); 324 325 if (ret != -EIOCBQUEUED) 326 cmd_rw_aio_complete(&aio_cmd->iocb, ret, 0); 327 328 return 0; 329 } 330 331 static int fd_do_rw(struct se_cmd *cmd, struct file *fd, 332 u32 block_size, struct scatterlist *sgl, 333 u32 sgl_nents, u32 data_length, int is_write) 334 { 335 struct scatterlist *sg; 336 struct iov_iter iter; 337 struct bio_vec *bvec; 338 ssize_t len = 0; 339 loff_t pos = (cmd->t_task_lba * block_size); 340 int ret = 0, i; 341 342 bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL); 343 if (!bvec) { 344 pr_err("Unable to allocate fd_do_readv iov[]\n"); 345 return -ENOMEM; 346 } 347 348 for_each_sg(sgl, sg, sgl_nents, i) { 349 bvec[i].bv_page = sg_page(sg); 350 bvec[i].bv_len = sg->length; 351 bvec[i].bv_offset = sg->offset; 352 353 len += sg->length; 354 } 355 356 iov_iter_bvec(&iter, READ, bvec, sgl_nents, len); 357 if (is_write) 358 ret = vfs_iter_write(fd, &iter, &pos, 0); 359 else 360 ret = vfs_iter_read(fd, &iter, &pos, 0); 361 362 if (is_write) { 363 if (ret < 0 || ret != data_length) { 364 pr_err("%s() write returned %d\n", __func__, ret); 365 if (ret >= 0) 366 ret = -EINVAL; 367 } 368 } else { 369 /* 370 * Return zeros and GOOD status even if the READ did not return 371 * the expected virt_size for struct file w/o a backing struct 372 * block_device. 373 */ 374 if (S_ISBLK(file_inode(fd)->i_mode)) { 375 if (ret < 0 || ret != data_length) { 376 pr_err("%s() returned %d, expecting %u for " 377 "S_ISBLK\n", __func__, ret, 378 data_length); 379 if (ret >= 0) 380 ret = -EINVAL; 381 } 382 } else { 383 if (ret < 0) { 384 pr_err("%s() returned %d for non S_ISBLK\n", 385 __func__, ret); 386 } else if (ret != data_length) { 387 /* 388 * Short read case: 389 * Probably some one truncate file under us. 390 * We must explicitly zero sg-pages to prevent 391 * expose uninizialized pages to userspace. 392 */ 393 if (ret < data_length) 394 ret += iov_iter_zero(data_length - ret, &iter); 395 else 396 ret = -EINVAL; 397 } 398 } 399 } 400 kfree(bvec); 401 return ret; 402 } 403 404 static sense_reason_t 405 fd_execute_sync_cache(struct se_cmd *cmd) 406 { 407 struct se_device *dev = cmd->se_dev; 408 struct fd_dev *fd_dev = FD_DEV(dev); 409 int immed = (cmd->t_task_cdb[1] & 0x2); 410 loff_t start, end; 411 int ret; 412 413 /* 414 * If the Immediate bit is set, queue up the GOOD response 415 * for this SYNCHRONIZE_CACHE op 416 */ 417 if (immed) 418 target_complete_cmd(cmd, SAM_STAT_GOOD); 419 420 /* 421 * Determine if we will be flushing the entire device. 422 */ 423 if (cmd->t_task_lba == 0 && cmd->data_length == 0) { 424 start = 0; 425 end = LLONG_MAX; 426 } else { 427 start = cmd->t_task_lba * dev->dev_attrib.block_size; 428 if (cmd->data_length) 429 end = start + cmd->data_length - 1; 430 else 431 end = LLONG_MAX; 432 } 433 434 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1); 435 if (ret != 0) 436 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret); 437 438 if (immed) 439 return 0; 440 441 if (ret) 442 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 443 else 444 target_complete_cmd(cmd, SAM_STAT_GOOD); 445 446 return 0; 447 } 448 449 static sense_reason_t 450 fd_execute_write_same(struct se_cmd *cmd) 451 { 452 struct se_device *se_dev = cmd->se_dev; 453 struct fd_dev *fd_dev = FD_DEV(se_dev); 454 loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size; 455 sector_t nolb = sbc_get_write_same_sectors(cmd); 456 struct iov_iter iter; 457 struct bio_vec *bvec; 458 unsigned int len = 0, i; 459 ssize_t ret; 460 461 if (!nolb) { 462 target_complete_cmd(cmd, SAM_STAT_GOOD); 463 return 0; 464 } 465 if (cmd->prot_op) { 466 pr_err("WRITE_SAME: Protection information with FILEIO" 467 " backends not supported\n"); 468 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 469 } 470 471 if (cmd->t_data_nents > 1 || 472 cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) { 473 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 474 " block_size: %u\n", 475 cmd->t_data_nents, 476 cmd->t_data_sg[0].length, 477 cmd->se_dev->dev_attrib.block_size); 478 return TCM_INVALID_CDB_FIELD; 479 } 480 481 bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL); 482 if (!bvec) 483 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 484 485 for (i = 0; i < nolb; i++) { 486 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]); 487 bvec[i].bv_len = cmd->t_data_sg[0].length; 488 bvec[i].bv_offset = cmd->t_data_sg[0].offset; 489 490 len += se_dev->dev_attrib.block_size; 491 } 492 493 iov_iter_bvec(&iter, READ, bvec, nolb, len); 494 ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0); 495 496 kfree(bvec); 497 if (ret < 0 || ret != len) { 498 pr_err("vfs_iter_write() returned %zd for write same\n", ret); 499 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 500 } 501 502 target_complete_cmd(cmd, SAM_STAT_GOOD); 503 return 0; 504 } 505 506 static int 507 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb, 508 void *buf, size_t bufsize) 509 { 510 struct fd_dev *fd_dev = FD_DEV(se_dev); 511 struct file *prot_fd = fd_dev->fd_prot_file; 512 sector_t prot_length, prot; 513 loff_t pos = lba * se_dev->prot_length; 514 515 if (!prot_fd) { 516 pr_err("Unable to locate fd_dev->fd_prot_file\n"); 517 return -ENODEV; 518 } 519 520 prot_length = nolb * se_dev->prot_length; 521 522 for (prot = 0; prot < prot_length;) { 523 sector_t len = min_t(sector_t, bufsize, prot_length - prot); 524 ssize_t ret = kernel_write(prot_fd, buf, len, &pos); 525 526 if (ret != len) { 527 pr_err("vfs_write to prot file failed: %zd\n", ret); 528 return ret < 0 ? ret : -ENODEV; 529 } 530 prot += ret; 531 } 532 533 return 0; 534 } 535 536 static int 537 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 538 { 539 void *buf; 540 int rc; 541 542 buf = (void *)__get_free_page(GFP_KERNEL); 543 if (!buf) { 544 pr_err("Unable to allocate FILEIO prot buf\n"); 545 return -ENOMEM; 546 } 547 memset(buf, 0xff, PAGE_SIZE); 548 549 rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE); 550 551 free_page((unsigned long)buf); 552 553 return rc; 554 } 555 556 static sense_reason_t 557 fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 558 { 559 struct file *file = FD_DEV(cmd->se_dev)->fd_file; 560 struct inode *inode = file->f_mapping->host; 561 int ret; 562 563 if (!nolb) { 564 return 0; 565 } 566 567 if (cmd->se_dev->dev_attrib.pi_prot_type) { 568 ret = fd_do_prot_unmap(cmd, lba, nolb); 569 if (ret) 570 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 571 } 572 573 if (S_ISBLK(inode->i_mode)) { 574 /* The backend is block device, use discard */ 575 struct block_device *bdev = inode->i_bdev; 576 struct se_device *dev = cmd->se_dev; 577 578 ret = blkdev_issue_discard(bdev, 579 target_to_linux_sector(dev, lba), 580 target_to_linux_sector(dev, nolb), 581 GFP_KERNEL, 0); 582 if (ret < 0) { 583 pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n", 584 ret); 585 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 586 } 587 } else { 588 /* The backend is normal file, use fallocate */ 589 struct se_device *se_dev = cmd->se_dev; 590 loff_t pos = lba * se_dev->dev_attrib.block_size; 591 unsigned int len = nolb * se_dev->dev_attrib.block_size; 592 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE; 593 594 if (!file->f_op->fallocate) 595 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 596 597 ret = file->f_op->fallocate(file, mode, pos, len); 598 if (ret < 0) { 599 pr_warn("FILEIO: fallocate() failed: %d\n", ret); 600 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 601 } 602 } 603 604 return 0; 605 } 606 607 static sense_reason_t 608 fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 609 enum dma_data_direction data_direction) 610 { 611 struct se_device *dev = cmd->se_dev; 612 struct fd_dev *fd_dev = FD_DEV(dev); 613 struct file *file = fd_dev->fd_file; 614 struct file *pfile = fd_dev->fd_prot_file; 615 sense_reason_t rc; 616 int ret = 0; 617 /* 618 * Call vectorized fileio functions to map struct scatterlist 619 * physical memory addresses to struct iovec virtual memory. 620 */ 621 if (data_direction == DMA_FROM_DEVICE) { 622 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 623 ret = fd_do_rw(cmd, pfile, dev->prot_length, 624 cmd->t_prot_sg, cmd->t_prot_nents, 625 cmd->prot_length, 0); 626 if (ret < 0) 627 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 628 } 629 630 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size, 631 sgl, sgl_nents, cmd->data_length, 0); 632 633 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type && 634 dev->dev_attrib.pi_prot_verify) { 635 u32 sectors = cmd->data_length >> 636 ilog2(dev->dev_attrib.block_size); 637 638 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 639 0, cmd->t_prot_sg, 0); 640 if (rc) 641 return rc; 642 } 643 } else { 644 if (cmd->prot_type && dev->dev_attrib.pi_prot_type && 645 dev->dev_attrib.pi_prot_verify) { 646 u32 sectors = cmd->data_length >> 647 ilog2(dev->dev_attrib.block_size); 648 649 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 650 0, cmd->t_prot_sg, 0); 651 if (rc) 652 return rc; 653 } 654 655 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size, 656 sgl, sgl_nents, cmd->data_length, 1); 657 /* 658 * Perform implicit vfs_fsync_range() for fd_do_writev() ops 659 * for SCSI WRITEs with Forced Unit Access (FUA) set. 660 * Allow this to happen independent of WCE=0 setting. 661 */ 662 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) { 663 loff_t start = cmd->t_task_lba * 664 dev->dev_attrib.block_size; 665 loff_t end; 666 667 if (cmd->data_length) 668 end = start + cmd->data_length - 1; 669 else 670 end = LLONG_MAX; 671 672 vfs_fsync_range(fd_dev->fd_file, start, end, 1); 673 } 674 675 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) { 676 ret = fd_do_rw(cmd, pfile, dev->prot_length, 677 cmd->t_prot_sg, cmd->t_prot_nents, 678 cmd->prot_length, 1); 679 if (ret < 0) 680 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 681 } 682 } 683 684 if (ret < 0) 685 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 686 687 target_complete_cmd(cmd, SAM_STAT_GOOD); 688 return 0; 689 } 690 691 static sense_reason_t 692 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 693 enum dma_data_direction data_direction) 694 { 695 struct se_device *dev = cmd->se_dev; 696 struct fd_dev *fd_dev = FD_DEV(dev); 697 698 /* 699 * We are currently limited by the number of iovecs (2048) per 700 * single vfs_[writev,readv] call. 701 */ 702 if (cmd->data_length > FD_MAX_BYTES) { 703 pr_err("FILEIO: Not able to process I/O of %u bytes due to" 704 "FD_MAX_BYTES: %u iovec count limitation\n", 705 cmd->data_length, FD_MAX_BYTES); 706 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 707 } 708 709 if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO) 710 return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction); 711 return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction); 712 } 713 714 enum { 715 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, 716 Opt_fd_async_io, Opt_err 717 }; 718 719 static match_table_t tokens = { 720 {Opt_fd_dev_name, "fd_dev_name=%s"}, 721 {Opt_fd_dev_size, "fd_dev_size=%s"}, 722 {Opt_fd_buffered_io, "fd_buffered_io=%d"}, 723 {Opt_fd_async_io, "fd_async_io=%d"}, 724 {Opt_err, NULL} 725 }; 726 727 static ssize_t fd_set_configfs_dev_params(struct se_device *dev, 728 const char *page, ssize_t count) 729 { 730 struct fd_dev *fd_dev = FD_DEV(dev); 731 char *orig, *ptr, *arg_p, *opts; 732 substring_t args[MAX_OPT_ARGS]; 733 int ret = 0, arg, token; 734 735 opts = kstrdup(page, GFP_KERNEL); 736 if (!opts) 737 return -ENOMEM; 738 739 orig = opts; 740 741 while ((ptr = strsep(&opts, ",\n")) != NULL) { 742 if (!*ptr) 743 continue; 744 745 token = match_token(ptr, tokens, args); 746 switch (token) { 747 case Opt_fd_dev_name: 748 if (match_strlcpy(fd_dev->fd_dev_name, &args[0], 749 FD_MAX_DEV_NAME) == 0) { 750 ret = -EINVAL; 751 break; 752 } 753 pr_debug("FILEIO: Referencing Path: %s\n", 754 fd_dev->fd_dev_name); 755 fd_dev->fbd_flags |= FBDF_HAS_PATH; 756 break; 757 case Opt_fd_dev_size: 758 arg_p = match_strdup(&args[0]); 759 if (!arg_p) { 760 ret = -ENOMEM; 761 break; 762 } 763 ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size); 764 kfree(arg_p); 765 if (ret < 0) { 766 pr_err("kstrtoull() failed for" 767 " fd_dev_size=\n"); 768 goto out; 769 } 770 pr_debug("FILEIO: Referencing Size: %llu" 771 " bytes\n", fd_dev->fd_dev_size); 772 fd_dev->fbd_flags |= FBDF_HAS_SIZE; 773 break; 774 case Opt_fd_buffered_io: 775 ret = match_int(args, &arg); 776 if (ret) 777 goto out; 778 if (arg != 1) { 779 pr_err("bogus fd_buffered_io=%d value\n", arg); 780 ret = -EINVAL; 781 goto out; 782 } 783 784 pr_debug("FILEIO: Using buffered I/O" 785 " operations for struct fd_dev\n"); 786 787 fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE; 788 break; 789 case Opt_fd_async_io: 790 ret = match_int(args, &arg); 791 if (ret) 792 goto out; 793 if (arg != 1) { 794 pr_err("bogus fd_async_io=%d value\n", arg); 795 ret = -EINVAL; 796 goto out; 797 } 798 799 pr_debug("FILEIO: Using async I/O" 800 " operations for struct fd_dev\n"); 801 802 fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO; 803 break; 804 default: 805 break; 806 } 807 } 808 809 out: 810 kfree(orig); 811 return (!ret) ? count : ret; 812 } 813 814 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b) 815 { 816 struct fd_dev *fd_dev = FD_DEV(dev); 817 ssize_t bl = 0; 818 819 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id); 820 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s Async: %d\n", 821 fd_dev->fd_dev_name, fd_dev->fd_dev_size, 822 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ? 823 "Buffered-WCE" : "O_DSYNC", 824 !!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)); 825 return bl; 826 } 827 828 static sector_t fd_get_blocks(struct se_device *dev) 829 { 830 struct fd_dev *fd_dev = FD_DEV(dev); 831 struct file *f = fd_dev->fd_file; 832 struct inode *i = f->f_mapping->host; 833 unsigned long long dev_size; 834 /* 835 * When using a file that references an underlying struct block_device, 836 * ensure dev_size is always based on the current inode size in order 837 * to handle underlying block_device resize operations. 838 */ 839 if (S_ISBLK(i->i_mode)) 840 dev_size = i_size_read(i); 841 else 842 dev_size = fd_dev->fd_dev_size; 843 844 return div_u64(dev_size - dev->dev_attrib.block_size, 845 dev->dev_attrib.block_size); 846 } 847 848 static int fd_init_prot(struct se_device *dev) 849 { 850 struct fd_dev *fd_dev = FD_DEV(dev); 851 struct file *prot_file, *file = fd_dev->fd_file; 852 struct inode *inode; 853 int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC; 854 char buf[FD_MAX_DEV_PROT_NAME]; 855 856 if (!file) { 857 pr_err("Unable to locate fd_dev->fd_file\n"); 858 return -ENODEV; 859 } 860 861 inode = file->f_mapping->host; 862 if (S_ISBLK(inode->i_mode)) { 863 pr_err("FILEIO Protection emulation only supported on" 864 " !S_ISBLK\n"); 865 return -ENOSYS; 866 } 867 868 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) 869 flags &= ~O_DSYNC; 870 871 snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection", 872 fd_dev->fd_dev_name); 873 874 prot_file = filp_open(buf, flags, 0600); 875 if (IS_ERR(prot_file)) { 876 pr_err("filp_open(%s) failed\n", buf); 877 ret = PTR_ERR(prot_file); 878 return ret; 879 } 880 fd_dev->fd_prot_file = prot_file; 881 882 return 0; 883 } 884 885 static int fd_format_prot(struct se_device *dev) 886 { 887 unsigned char *buf; 888 int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size; 889 int ret; 890 891 if (!dev->dev_attrib.pi_prot_type) { 892 pr_err("Unable to format_prot while pi_prot_type == 0\n"); 893 return -ENODEV; 894 } 895 896 buf = vzalloc(unit_size); 897 if (!buf) { 898 pr_err("Unable to allocate FILEIO prot buf\n"); 899 return -ENOMEM; 900 } 901 902 pr_debug("Using FILEIO prot_length: %llu\n", 903 (unsigned long long)(dev->transport->get_blocks(dev) + 1) * 904 dev->prot_length); 905 906 memset(buf, 0xff, unit_size); 907 ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1, 908 buf, unit_size); 909 vfree(buf); 910 return ret; 911 } 912 913 static void fd_free_prot(struct se_device *dev) 914 { 915 struct fd_dev *fd_dev = FD_DEV(dev); 916 917 if (!fd_dev->fd_prot_file) 918 return; 919 920 filp_close(fd_dev->fd_prot_file, NULL); 921 fd_dev->fd_prot_file = NULL; 922 } 923 924 static struct sbc_ops fd_sbc_ops = { 925 .execute_rw = fd_execute_rw, 926 .execute_sync_cache = fd_execute_sync_cache, 927 .execute_write_same = fd_execute_write_same, 928 .execute_unmap = fd_execute_unmap, 929 }; 930 931 static sense_reason_t 932 fd_parse_cdb(struct se_cmd *cmd) 933 { 934 return sbc_parse_cdb(cmd, &fd_sbc_ops); 935 } 936 937 static const struct target_backend_ops fileio_ops = { 938 .name = "fileio", 939 .inquiry_prod = "FILEIO", 940 .inquiry_rev = FD_VERSION, 941 .owner = THIS_MODULE, 942 .attach_hba = fd_attach_hba, 943 .detach_hba = fd_detach_hba, 944 .alloc_device = fd_alloc_device, 945 .configure_device = fd_configure_device, 946 .destroy_device = fd_destroy_device, 947 .free_device = fd_free_device, 948 .parse_cdb = fd_parse_cdb, 949 .set_configfs_dev_params = fd_set_configfs_dev_params, 950 .show_configfs_dev_params = fd_show_configfs_dev_params, 951 .get_device_type = sbc_get_device_type, 952 .get_blocks = fd_get_blocks, 953 .init_prot = fd_init_prot, 954 .format_prot = fd_format_prot, 955 .free_prot = fd_free_prot, 956 .tb_dev_attrib_attrs = sbc_attrib_attrs, 957 }; 958 959 static int __init fileio_module_init(void) 960 { 961 return transport_backend_register(&fileio_ops); 962 } 963 964 static void __exit fileio_module_exit(void) 965 { 966 target_backend_unregister(&fileio_ops); 967 } 968 969 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin"); 970 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 971 MODULE_LICENSE("GPL"); 972 973 module_init(fileio_module_init); 974 module_exit(fileio_module_exit); 975