1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /******************************************************************************* 3 * Filename: target_core_file.c 4 * 5 * This file contains the Storage Engine <-> FILEIO transport specific functions 6 * 7 * (c) Copyright 2005-2013 Datera, Inc. 8 * 9 * Nicholas A. Bellinger <nab@kernel.org> 10 * 11 ******************************************************************************/ 12 13 #include <linux/string.h> 14 #include <linux/parser.h> 15 #include <linux/timer.h> 16 #include <linux/blkdev.h> 17 #include <linux/slab.h> 18 #include <linux/spinlock.h> 19 #include <linux/module.h> 20 #include <linux/vmalloc.h> 21 #include <linux/falloc.h> 22 #include <linux/uio.h> 23 #include <scsi/scsi_proto.h> 24 #include <asm/unaligned.h> 25 26 #include <target/target_core_base.h> 27 #include <target/target_core_backend.h> 28 29 #include "target_core_file.h" 30 31 static inline struct fd_dev *FD_DEV(struct se_device *dev) 32 { 33 return container_of(dev, struct fd_dev, dev); 34 } 35 36 static int fd_attach_hba(struct se_hba *hba, u32 host_id) 37 { 38 struct fd_host *fd_host; 39 40 fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL); 41 if (!fd_host) { 42 pr_err("Unable to allocate memory for struct fd_host\n"); 43 return -ENOMEM; 44 } 45 46 fd_host->fd_host_id = host_id; 47 48 hba->hba_ptr = fd_host; 49 50 pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic" 51 " Target Core Stack %s\n", hba->hba_id, FD_VERSION, 52 TARGET_CORE_VERSION); 53 pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n", 54 hba->hba_id, fd_host->fd_host_id); 55 56 return 0; 57 } 58 59 static void fd_detach_hba(struct se_hba *hba) 60 { 61 struct fd_host *fd_host = hba->hba_ptr; 62 63 pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic" 64 " Target Core\n", hba->hba_id, fd_host->fd_host_id); 65 66 kfree(fd_host); 67 hba->hba_ptr = NULL; 68 } 69 70 static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name) 71 { 72 struct fd_dev *fd_dev; 73 struct fd_host *fd_host = hba->hba_ptr; 74 75 fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL); 76 if (!fd_dev) { 77 pr_err("Unable to allocate memory for struct fd_dev\n"); 78 return NULL; 79 } 80 81 fd_dev->fd_host = fd_host; 82 83 pr_debug("FILEIO: Allocated fd_dev for %p\n", name); 84 85 return &fd_dev->dev; 86 } 87 88 static int fd_configure_device(struct se_device *dev) 89 { 90 struct fd_dev *fd_dev = FD_DEV(dev); 91 struct fd_host *fd_host = dev->se_hba->hba_ptr; 92 struct file *file; 93 struct inode *inode = NULL; 94 int flags, ret = -EINVAL; 95 96 if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) { 97 pr_err("Missing fd_dev_name=\n"); 98 return -EINVAL; 99 } 100 101 /* 102 * Use O_DSYNC by default instead of O_SYNC to forgo syncing 103 * of pure timestamp updates. 104 */ 105 flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC; 106 107 /* 108 * Optionally allow fd_buffered_io=1 to be enabled for people 109 * who want use the fs buffer cache as an WriteCache mechanism. 110 * 111 * This means that in event of a hard failure, there is a risk 112 * of silent data-loss if the SCSI client has *not* performed a 113 * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE 114 * to write-out the entire device cache. 115 */ 116 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) { 117 pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n"); 118 flags &= ~O_DSYNC; 119 } 120 121 file = filp_open(fd_dev->fd_dev_name, flags, 0600); 122 if (IS_ERR(file)) { 123 pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name); 124 ret = PTR_ERR(file); 125 goto fail; 126 } 127 fd_dev->fd_file = file; 128 /* 129 * If using a block backend with this struct file, we extract 130 * fd_dev->fd_[block,dev]_size from struct block_device. 131 * 132 * Otherwise, we use the passed fd_size= from configfs 133 */ 134 inode = file->f_mapping->host; 135 if (S_ISBLK(inode->i_mode)) { 136 struct request_queue *q = bdev_get_queue(I_BDEV(inode)); 137 unsigned long long dev_size; 138 139 fd_dev->fd_block_size = bdev_logical_block_size(I_BDEV(inode)); 140 /* 141 * Determine the number of bytes from i_size_read() minus 142 * one (1) logical sector from underlying struct block_device 143 */ 144 dev_size = (i_size_read(file->f_mapping->host) - 145 fd_dev->fd_block_size); 146 147 pr_debug("FILEIO: Using size: %llu bytes from struct" 148 " block_device blocks: %llu logical_block_size: %d\n", 149 dev_size, div_u64(dev_size, fd_dev->fd_block_size), 150 fd_dev->fd_block_size); 151 152 if (target_configure_unmap_from_queue(&dev->dev_attrib, q)) 153 pr_debug("IFILE: BLOCK Discard support available," 154 " disabled by default\n"); 155 /* 156 * Enable write same emulation for IBLOCK and use 0xFFFF as 157 * the smaller WRITE_SAME(10) only has a two-byte block count. 158 */ 159 dev->dev_attrib.max_write_same_len = 0xFFFF; 160 161 if (blk_queue_nonrot(q)) 162 dev->dev_attrib.is_nonrot = 1; 163 } else { 164 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) { 165 pr_err("FILEIO: Missing fd_dev_size=" 166 " parameter, and no backing struct" 167 " block_device\n"); 168 goto fail; 169 } 170 171 fd_dev->fd_block_size = FD_BLOCKSIZE; 172 /* 173 * Limit UNMAP emulation to 8k Number of LBAs (NoLB) 174 */ 175 dev->dev_attrib.max_unmap_lba_count = 0x2000; 176 /* 177 * Currently hardcoded to 1 in Linux/SCSI code.. 178 */ 179 dev->dev_attrib.max_unmap_block_desc_count = 1; 180 dev->dev_attrib.unmap_granularity = 1; 181 dev->dev_attrib.unmap_granularity_alignment = 0; 182 183 /* 184 * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB) 185 * based upon struct iovec limit for vfs_writev() 186 */ 187 dev->dev_attrib.max_write_same_len = 0x1000; 188 } 189 190 dev->dev_attrib.hw_block_size = fd_dev->fd_block_size; 191 dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES; 192 dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size; 193 dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH; 194 195 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) { 196 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1" 197 " with FDBD_HAS_BUFFERED_IO_WCE\n"); 198 dev->dev_attrib.emulate_write_cache = 1; 199 } 200 201 fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++; 202 fd_dev->fd_queue_depth = dev->queue_depth; 203 204 pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s," 205 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id, 206 fd_dev->fd_dev_name, fd_dev->fd_dev_size); 207 208 return 0; 209 fail: 210 if (fd_dev->fd_file) { 211 filp_close(fd_dev->fd_file, NULL); 212 fd_dev->fd_file = NULL; 213 } 214 return ret; 215 } 216 217 static void fd_dev_call_rcu(struct rcu_head *p) 218 { 219 struct se_device *dev = container_of(p, struct se_device, rcu_head); 220 struct fd_dev *fd_dev = FD_DEV(dev); 221 222 kfree(fd_dev); 223 } 224 225 static void fd_free_device(struct se_device *dev) 226 { 227 call_rcu(&dev->rcu_head, fd_dev_call_rcu); 228 } 229 230 static void fd_destroy_device(struct se_device *dev) 231 { 232 struct fd_dev *fd_dev = FD_DEV(dev); 233 234 if (fd_dev->fd_file) { 235 filp_close(fd_dev->fd_file, NULL); 236 fd_dev->fd_file = NULL; 237 } 238 } 239 240 struct target_core_file_cmd { 241 unsigned long len; 242 struct se_cmd *cmd; 243 struct kiocb iocb; 244 struct bio_vec bvecs[]; 245 }; 246 247 static void cmd_rw_aio_complete(struct kiocb *iocb, long ret, long ret2) 248 { 249 struct target_core_file_cmd *cmd; 250 251 cmd = container_of(iocb, struct target_core_file_cmd, iocb); 252 253 if (ret != cmd->len) 254 target_complete_cmd(cmd->cmd, SAM_STAT_CHECK_CONDITION); 255 else 256 target_complete_cmd(cmd->cmd, SAM_STAT_GOOD); 257 258 kfree(cmd); 259 } 260 261 static sense_reason_t 262 fd_execute_rw_aio(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 263 enum dma_data_direction data_direction) 264 { 265 int is_write = !(data_direction == DMA_FROM_DEVICE); 266 struct se_device *dev = cmd->se_dev; 267 struct fd_dev *fd_dev = FD_DEV(dev); 268 struct file *file = fd_dev->fd_file; 269 struct target_core_file_cmd *aio_cmd; 270 struct iov_iter iter; 271 struct scatterlist *sg; 272 ssize_t len = 0; 273 int ret = 0, i; 274 275 aio_cmd = kmalloc(struct_size(aio_cmd, bvecs, sgl_nents), GFP_KERNEL); 276 if (!aio_cmd) 277 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 278 279 for_each_sg(sgl, sg, sgl_nents, i) { 280 aio_cmd->bvecs[i].bv_page = sg_page(sg); 281 aio_cmd->bvecs[i].bv_len = sg->length; 282 aio_cmd->bvecs[i].bv_offset = sg->offset; 283 284 len += sg->length; 285 } 286 287 iov_iter_bvec(&iter, is_write, aio_cmd->bvecs, sgl_nents, len); 288 289 aio_cmd->cmd = cmd; 290 aio_cmd->len = len; 291 aio_cmd->iocb.ki_pos = cmd->t_task_lba * dev->dev_attrib.block_size; 292 aio_cmd->iocb.ki_filp = file; 293 aio_cmd->iocb.ki_complete = cmd_rw_aio_complete; 294 aio_cmd->iocb.ki_flags = IOCB_DIRECT; 295 296 if (is_write && (cmd->se_cmd_flags & SCF_FUA)) 297 aio_cmd->iocb.ki_flags |= IOCB_DSYNC; 298 299 if (is_write) 300 ret = call_write_iter(file, &aio_cmd->iocb, &iter); 301 else 302 ret = call_read_iter(file, &aio_cmd->iocb, &iter); 303 304 if (ret != -EIOCBQUEUED) 305 cmd_rw_aio_complete(&aio_cmd->iocb, ret, 0); 306 307 return 0; 308 } 309 310 static int fd_do_rw(struct se_cmd *cmd, struct file *fd, 311 u32 block_size, struct scatterlist *sgl, 312 u32 sgl_nents, u32 data_length, int is_write) 313 { 314 struct scatterlist *sg; 315 struct iov_iter iter; 316 struct bio_vec *bvec; 317 ssize_t len = 0; 318 loff_t pos = (cmd->t_task_lba * block_size); 319 int ret = 0, i; 320 321 bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL); 322 if (!bvec) { 323 pr_err("Unable to allocate fd_do_readv iov[]\n"); 324 return -ENOMEM; 325 } 326 327 for_each_sg(sgl, sg, sgl_nents, i) { 328 bvec[i].bv_page = sg_page(sg); 329 bvec[i].bv_len = sg->length; 330 bvec[i].bv_offset = sg->offset; 331 332 len += sg->length; 333 } 334 335 iov_iter_bvec(&iter, READ, bvec, sgl_nents, len); 336 if (is_write) 337 ret = vfs_iter_write(fd, &iter, &pos, 0); 338 else 339 ret = vfs_iter_read(fd, &iter, &pos, 0); 340 341 if (is_write) { 342 if (ret < 0 || ret != data_length) { 343 pr_err("%s() write returned %d\n", __func__, ret); 344 if (ret >= 0) 345 ret = -EINVAL; 346 } 347 } else { 348 /* 349 * Return zeros and GOOD status even if the READ did not return 350 * the expected virt_size for struct file w/o a backing struct 351 * block_device. 352 */ 353 if (S_ISBLK(file_inode(fd)->i_mode)) { 354 if (ret < 0 || ret != data_length) { 355 pr_err("%s() returned %d, expecting %u for " 356 "S_ISBLK\n", __func__, ret, 357 data_length); 358 if (ret >= 0) 359 ret = -EINVAL; 360 } 361 } else { 362 if (ret < 0) { 363 pr_err("%s() returned %d for non S_ISBLK\n", 364 __func__, ret); 365 } else if (ret != data_length) { 366 /* 367 * Short read case: 368 * Probably some one truncate file under us. 369 * We must explicitly zero sg-pages to prevent 370 * expose uninizialized pages to userspace. 371 */ 372 if (ret < data_length) 373 ret += iov_iter_zero(data_length - ret, &iter); 374 else 375 ret = -EINVAL; 376 } 377 } 378 } 379 kfree(bvec); 380 return ret; 381 } 382 383 static sense_reason_t 384 fd_execute_sync_cache(struct se_cmd *cmd) 385 { 386 struct se_device *dev = cmd->se_dev; 387 struct fd_dev *fd_dev = FD_DEV(dev); 388 int immed = (cmd->t_task_cdb[1] & 0x2); 389 loff_t start, end; 390 int ret; 391 392 /* 393 * If the Immediate bit is set, queue up the GOOD response 394 * for this SYNCHRONIZE_CACHE op 395 */ 396 if (immed) 397 target_complete_cmd(cmd, SAM_STAT_GOOD); 398 399 /* 400 * Determine if we will be flushing the entire device. 401 */ 402 if (cmd->t_task_lba == 0 && cmd->data_length == 0) { 403 start = 0; 404 end = LLONG_MAX; 405 } else { 406 start = cmd->t_task_lba * dev->dev_attrib.block_size; 407 if (cmd->data_length) 408 end = start + cmd->data_length - 1; 409 else 410 end = LLONG_MAX; 411 } 412 413 ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1); 414 if (ret != 0) 415 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret); 416 417 if (immed) 418 return 0; 419 420 if (ret) 421 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION); 422 else 423 target_complete_cmd(cmd, SAM_STAT_GOOD); 424 425 return 0; 426 } 427 428 static sense_reason_t 429 fd_execute_write_same(struct se_cmd *cmd) 430 { 431 struct se_device *se_dev = cmd->se_dev; 432 struct fd_dev *fd_dev = FD_DEV(se_dev); 433 loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size; 434 sector_t nolb = sbc_get_write_same_sectors(cmd); 435 struct iov_iter iter; 436 struct bio_vec *bvec; 437 unsigned int len = 0, i; 438 ssize_t ret; 439 440 if (!nolb) { 441 target_complete_cmd(cmd, SAM_STAT_GOOD); 442 return 0; 443 } 444 if (cmd->prot_op) { 445 pr_err("WRITE_SAME: Protection information with FILEIO" 446 " backends not supported\n"); 447 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 448 } 449 450 if (cmd->t_data_nents > 1 || 451 cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) { 452 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u" 453 " block_size: %u\n", 454 cmd->t_data_nents, 455 cmd->t_data_sg[0].length, 456 cmd->se_dev->dev_attrib.block_size); 457 return TCM_INVALID_CDB_FIELD; 458 } 459 460 bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL); 461 if (!bvec) 462 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 463 464 for (i = 0; i < nolb; i++) { 465 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]); 466 bvec[i].bv_len = cmd->t_data_sg[0].length; 467 bvec[i].bv_offset = cmd->t_data_sg[0].offset; 468 469 len += se_dev->dev_attrib.block_size; 470 } 471 472 iov_iter_bvec(&iter, READ, bvec, nolb, len); 473 ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos, 0); 474 475 kfree(bvec); 476 if (ret < 0 || ret != len) { 477 pr_err("vfs_iter_write() returned %zd for write same\n", ret); 478 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 479 } 480 481 target_complete_cmd(cmd, SAM_STAT_GOOD); 482 return 0; 483 } 484 485 static int 486 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb, 487 void *buf, size_t bufsize) 488 { 489 struct fd_dev *fd_dev = FD_DEV(se_dev); 490 struct file *prot_fd = fd_dev->fd_prot_file; 491 sector_t prot_length, prot; 492 loff_t pos = lba * se_dev->prot_length; 493 494 if (!prot_fd) { 495 pr_err("Unable to locate fd_dev->fd_prot_file\n"); 496 return -ENODEV; 497 } 498 499 prot_length = nolb * se_dev->prot_length; 500 501 memset(buf, 0xff, bufsize); 502 for (prot = 0; prot < prot_length;) { 503 sector_t len = min_t(sector_t, bufsize, prot_length - prot); 504 ssize_t ret = kernel_write(prot_fd, buf, len, &pos); 505 506 if (ret != len) { 507 pr_err("vfs_write to prot file failed: %zd\n", ret); 508 return ret < 0 ? ret : -ENODEV; 509 } 510 prot += ret; 511 } 512 513 return 0; 514 } 515 516 static int 517 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 518 { 519 void *buf; 520 int rc; 521 522 buf = (void *)__get_free_page(GFP_KERNEL); 523 if (!buf) { 524 pr_err("Unable to allocate FILEIO prot buf\n"); 525 return -ENOMEM; 526 } 527 528 rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE); 529 530 free_page((unsigned long)buf); 531 532 return rc; 533 } 534 535 static sense_reason_t 536 fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb) 537 { 538 struct file *file = FD_DEV(cmd->se_dev)->fd_file; 539 struct inode *inode = file->f_mapping->host; 540 int ret; 541 542 if (!nolb) { 543 return 0; 544 } 545 546 if (cmd->se_dev->dev_attrib.pi_prot_type) { 547 ret = fd_do_prot_unmap(cmd, lba, nolb); 548 if (ret) 549 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 550 } 551 552 if (S_ISBLK(inode->i_mode)) { 553 /* The backend is block device, use discard */ 554 struct block_device *bdev = I_BDEV(inode); 555 struct se_device *dev = cmd->se_dev; 556 557 ret = blkdev_issue_discard(bdev, 558 target_to_linux_sector(dev, lba), 559 target_to_linux_sector(dev, nolb), 560 GFP_KERNEL, 0); 561 if (ret < 0) { 562 pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n", 563 ret); 564 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 565 } 566 } else { 567 /* The backend is normal file, use fallocate */ 568 struct se_device *se_dev = cmd->se_dev; 569 loff_t pos = lba * se_dev->dev_attrib.block_size; 570 unsigned int len = nolb * se_dev->dev_attrib.block_size; 571 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE; 572 573 if (!file->f_op->fallocate) 574 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 575 576 ret = file->f_op->fallocate(file, mode, pos, len); 577 if (ret < 0) { 578 pr_warn("FILEIO: fallocate() failed: %d\n", ret); 579 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 580 } 581 } 582 583 return 0; 584 } 585 586 static sense_reason_t 587 fd_execute_rw_buffered(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 588 enum dma_data_direction data_direction) 589 { 590 struct se_device *dev = cmd->se_dev; 591 struct fd_dev *fd_dev = FD_DEV(dev); 592 struct file *file = fd_dev->fd_file; 593 struct file *pfile = fd_dev->fd_prot_file; 594 sense_reason_t rc; 595 int ret = 0; 596 /* 597 * Call vectorized fileio functions to map struct scatterlist 598 * physical memory addresses to struct iovec virtual memory. 599 */ 600 if (data_direction == DMA_FROM_DEVICE) { 601 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) { 602 ret = fd_do_rw(cmd, pfile, dev->prot_length, 603 cmd->t_prot_sg, cmd->t_prot_nents, 604 cmd->prot_length, 0); 605 if (ret < 0) 606 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 607 } 608 609 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size, 610 sgl, sgl_nents, cmd->data_length, 0); 611 612 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type && 613 dev->dev_attrib.pi_prot_verify) { 614 u32 sectors = cmd->data_length >> 615 ilog2(dev->dev_attrib.block_size); 616 617 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 618 0, cmd->t_prot_sg, 0); 619 if (rc) 620 return rc; 621 } 622 } else { 623 if (cmd->prot_type && dev->dev_attrib.pi_prot_type && 624 dev->dev_attrib.pi_prot_verify) { 625 u32 sectors = cmd->data_length >> 626 ilog2(dev->dev_attrib.block_size); 627 628 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 629 0, cmd->t_prot_sg, 0); 630 if (rc) 631 return rc; 632 } 633 634 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size, 635 sgl, sgl_nents, cmd->data_length, 1); 636 /* 637 * Perform implicit vfs_fsync_range() for fd_do_writev() ops 638 * for SCSI WRITEs with Forced Unit Access (FUA) set. 639 * Allow this to happen independent of WCE=0 setting. 640 */ 641 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) { 642 loff_t start = cmd->t_task_lba * 643 dev->dev_attrib.block_size; 644 loff_t end; 645 646 if (cmd->data_length) 647 end = start + cmd->data_length - 1; 648 else 649 end = LLONG_MAX; 650 651 vfs_fsync_range(fd_dev->fd_file, start, end, 1); 652 } 653 654 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) { 655 ret = fd_do_rw(cmd, pfile, dev->prot_length, 656 cmd->t_prot_sg, cmd->t_prot_nents, 657 cmd->prot_length, 1); 658 if (ret < 0) 659 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 660 } 661 } 662 663 if (ret < 0) 664 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 665 666 target_complete_cmd(cmd, SAM_STAT_GOOD); 667 return 0; 668 } 669 670 static sense_reason_t 671 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, 672 enum dma_data_direction data_direction) 673 { 674 struct se_device *dev = cmd->se_dev; 675 struct fd_dev *fd_dev = FD_DEV(dev); 676 677 /* 678 * We are currently limited by the number of iovecs (2048) per 679 * single vfs_[writev,readv] call. 680 */ 681 if (cmd->data_length > FD_MAX_BYTES) { 682 pr_err("FILEIO: Not able to process I/O of %u bytes due to" 683 "FD_MAX_BYTES: %u iovec count limitation\n", 684 cmd->data_length, FD_MAX_BYTES); 685 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; 686 } 687 688 if (fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO) 689 return fd_execute_rw_aio(cmd, sgl, sgl_nents, data_direction); 690 return fd_execute_rw_buffered(cmd, sgl, sgl_nents, data_direction); 691 } 692 693 enum { 694 Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, 695 Opt_fd_async_io, Opt_err 696 }; 697 698 static match_table_t tokens = { 699 {Opt_fd_dev_name, "fd_dev_name=%s"}, 700 {Opt_fd_dev_size, "fd_dev_size=%s"}, 701 {Opt_fd_buffered_io, "fd_buffered_io=%d"}, 702 {Opt_fd_async_io, "fd_async_io=%d"}, 703 {Opt_err, NULL} 704 }; 705 706 static ssize_t fd_set_configfs_dev_params(struct se_device *dev, 707 const char *page, ssize_t count) 708 { 709 struct fd_dev *fd_dev = FD_DEV(dev); 710 char *orig, *ptr, *arg_p, *opts; 711 substring_t args[MAX_OPT_ARGS]; 712 int ret = 0, arg, token; 713 714 opts = kstrdup(page, GFP_KERNEL); 715 if (!opts) 716 return -ENOMEM; 717 718 orig = opts; 719 720 while ((ptr = strsep(&opts, ",\n")) != NULL) { 721 if (!*ptr) 722 continue; 723 724 token = match_token(ptr, tokens, args); 725 switch (token) { 726 case Opt_fd_dev_name: 727 if (match_strlcpy(fd_dev->fd_dev_name, &args[0], 728 FD_MAX_DEV_NAME) == 0) { 729 ret = -EINVAL; 730 break; 731 } 732 pr_debug("FILEIO: Referencing Path: %s\n", 733 fd_dev->fd_dev_name); 734 fd_dev->fbd_flags |= FBDF_HAS_PATH; 735 break; 736 case Opt_fd_dev_size: 737 arg_p = match_strdup(&args[0]); 738 if (!arg_p) { 739 ret = -ENOMEM; 740 break; 741 } 742 ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size); 743 kfree(arg_p); 744 if (ret < 0) { 745 pr_err("kstrtoull() failed for" 746 " fd_dev_size=\n"); 747 goto out; 748 } 749 pr_debug("FILEIO: Referencing Size: %llu" 750 " bytes\n", fd_dev->fd_dev_size); 751 fd_dev->fbd_flags |= FBDF_HAS_SIZE; 752 break; 753 case Opt_fd_buffered_io: 754 ret = match_int(args, &arg); 755 if (ret) 756 goto out; 757 if (arg != 1) { 758 pr_err("bogus fd_buffered_io=%d value\n", arg); 759 ret = -EINVAL; 760 goto out; 761 } 762 763 pr_debug("FILEIO: Using buffered I/O" 764 " operations for struct fd_dev\n"); 765 766 fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE; 767 break; 768 case Opt_fd_async_io: 769 ret = match_int(args, &arg); 770 if (ret) 771 goto out; 772 if (arg != 1) { 773 pr_err("bogus fd_async_io=%d value\n", arg); 774 ret = -EINVAL; 775 goto out; 776 } 777 778 pr_debug("FILEIO: Using async I/O" 779 " operations for struct fd_dev\n"); 780 781 fd_dev->fbd_flags |= FDBD_HAS_ASYNC_IO; 782 break; 783 default: 784 break; 785 } 786 } 787 788 out: 789 kfree(orig); 790 return (!ret) ? count : ret; 791 } 792 793 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b) 794 { 795 struct fd_dev *fd_dev = FD_DEV(dev); 796 ssize_t bl = 0; 797 798 bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id); 799 bl += sprintf(b + bl, " File: %s Size: %llu Mode: %s Async: %d\n", 800 fd_dev->fd_dev_name, fd_dev->fd_dev_size, 801 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ? 802 "Buffered-WCE" : "O_DSYNC", 803 !!(fd_dev->fbd_flags & FDBD_HAS_ASYNC_IO)); 804 return bl; 805 } 806 807 static sector_t fd_get_blocks(struct se_device *dev) 808 { 809 struct fd_dev *fd_dev = FD_DEV(dev); 810 struct file *f = fd_dev->fd_file; 811 struct inode *i = f->f_mapping->host; 812 unsigned long long dev_size; 813 /* 814 * When using a file that references an underlying struct block_device, 815 * ensure dev_size is always based on the current inode size in order 816 * to handle underlying block_device resize operations. 817 */ 818 if (S_ISBLK(i->i_mode)) 819 dev_size = i_size_read(i); 820 else 821 dev_size = fd_dev->fd_dev_size; 822 823 return div_u64(dev_size - dev->dev_attrib.block_size, 824 dev->dev_attrib.block_size); 825 } 826 827 static int fd_init_prot(struct se_device *dev) 828 { 829 struct fd_dev *fd_dev = FD_DEV(dev); 830 struct file *prot_file, *file = fd_dev->fd_file; 831 struct inode *inode; 832 int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC; 833 char buf[FD_MAX_DEV_PROT_NAME]; 834 835 if (!file) { 836 pr_err("Unable to locate fd_dev->fd_file\n"); 837 return -ENODEV; 838 } 839 840 inode = file->f_mapping->host; 841 if (S_ISBLK(inode->i_mode)) { 842 pr_err("FILEIO Protection emulation only supported on" 843 " !S_ISBLK\n"); 844 return -ENOSYS; 845 } 846 847 if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) 848 flags &= ~O_DSYNC; 849 850 snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection", 851 fd_dev->fd_dev_name); 852 853 prot_file = filp_open(buf, flags, 0600); 854 if (IS_ERR(prot_file)) { 855 pr_err("filp_open(%s) failed\n", buf); 856 ret = PTR_ERR(prot_file); 857 return ret; 858 } 859 fd_dev->fd_prot_file = prot_file; 860 861 return 0; 862 } 863 864 static int fd_format_prot(struct se_device *dev) 865 { 866 unsigned char *buf; 867 int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size; 868 int ret; 869 870 if (!dev->dev_attrib.pi_prot_type) { 871 pr_err("Unable to format_prot while pi_prot_type == 0\n"); 872 return -ENODEV; 873 } 874 875 buf = vzalloc(unit_size); 876 if (!buf) { 877 pr_err("Unable to allocate FILEIO prot buf\n"); 878 return -ENOMEM; 879 } 880 881 pr_debug("Using FILEIO prot_length: %llu\n", 882 (unsigned long long)(dev->transport->get_blocks(dev) + 1) * 883 dev->prot_length); 884 885 ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1, 886 buf, unit_size); 887 vfree(buf); 888 return ret; 889 } 890 891 static void fd_free_prot(struct se_device *dev) 892 { 893 struct fd_dev *fd_dev = FD_DEV(dev); 894 895 if (!fd_dev->fd_prot_file) 896 return; 897 898 filp_close(fd_dev->fd_prot_file, NULL); 899 fd_dev->fd_prot_file = NULL; 900 } 901 902 static struct sbc_ops fd_sbc_ops = { 903 .execute_rw = fd_execute_rw, 904 .execute_sync_cache = fd_execute_sync_cache, 905 .execute_write_same = fd_execute_write_same, 906 .execute_unmap = fd_execute_unmap, 907 }; 908 909 static sense_reason_t 910 fd_parse_cdb(struct se_cmd *cmd) 911 { 912 return sbc_parse_cdb(cmd, &fd_sbc_ops); 913 } 914 915 static const struct target_backend_ops fileio_ops = { 916 .name = "fileio", 917 .inquiry_prod = "FILEIO", 918 .inquiry_rev = FD_VERSION, 919 .owner = THIS_MODULE, 920 .attach_hba = fd_attach_hba, 921 .detach_hba = fd_detach_hba, 922 .alloc_device = fd_alloc_device, 923 .configure_device = fd_configure_device, 924 .destroy_device = fd_destroy_device, 925 .free_device = fd_free_device, 926 .parse_cdb = fd_parse_cdb, 927 .set_configfs_dev_params = fd_set_configfs_dev_params, 928 .show_configfs_dev_params = fd_show_configfs_dev_params, 929 .get_device_type = sbc_get_device_type, 930 .get_blocks = fd_get_blocks, 931 .init_prot = fd_init_prot, 932 .format_prot = fd_format_prot, 933 .free_prot = fd_free_prot, 934 .tb_dev_attrib_attrs = sbc_attrib_attrs, 935 }; 936 937 static int __init fileio_module_init(void) 938 { 939 return transport_backend_register(&fileio_ops); 940 } 941 942 static void __exit fileio_module_exit(void) 943 { 944 target_backend_unregister(&fileio_ops); 945 } 946 947 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin"); 948 MODULE_AUTHOR("nab@Linux-iSCSI.org"); 949 MODULE_LICENSE("GPL"); 950 951 module_init(fileio_module_init); 952 module_exit(fileio_module_exit); 953