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