drivers/target/target_core_file.c

   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         struct fd_dev *fd_dev = FD_DEV(dev);
 241
 242         if (fd_dev->fd_file) {
 243                 filp_close(fd_dev->fd_file, NULL);
 244                 fd_dev->fd_file = NULL;
 245         }
 246         call_rcu(&dev->rcu_head, fd_dev_call_rcu);
 247 }
 248
 249 static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
 250                     u32 block_size, struct scatterlist *sgl,
 251                     u32 sgl_nents, u32 data_length, int is_write)
 252 {
 253         struct scatterlist *sg;
 254         struct iov_iter iter;
 255         struct bio_vec *bvec;
 256         ssize_t len = 0;
 257         loff_t pos = (cmd->t_task_lba * block_size);
 258         int ret = 0, i;
 259
 260         bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
 261         if (!bvec) {
 262                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 263                 return -ENOMEM;
 264         }
 265
 266         for_each_sg(sgl, sg, sgl_nents, i) {
 267                 bvec[i].bv_page = sg_page(sg);
 268                 bvec[i].bv_len = sg->length;
 269                 bvec[i].bv_offset = sg->offset;
 270
 271                 len += sg->length;
 272         }
 273
 274         iov_iter_bvec(&iter, ITER_BVEC, bvec, sgl_nents, len);
 275         if (is_write)
 276                 ret = vfs_iter_write(fd, &iter, &pos);
 277         else
 278                 ret = vfs_iter_read(fd, &iter, &pos);
 279
 280         if (is_write) {
 281                 if (ret < 0 || ret != data_length) {
 282                         pr_err("%s() write returned %d\n", __func__, ret);
 283                         if (ret >= 0)
 284                                 ret = -EINVAL;
 285                 }
 286         } else {
 287                 /*
 288                  * Return zeros and GOOD status even if the READ did not return
 289                  * the expected virt_size for struct file w/o a backing struct
 290                  * block_device.
 291                  */
 292                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 293                         if (ret < 0 || ret != data_length) {
 294                                 pr_err("%s() returned %d, expecting %u for "
 295                                                 "S_ISBLK\n", __func__, ret,
 296                                                 data_length);
 297                                 if (ret >= 0)
 298                                         ret = -EINVAL;
 299                         }
 300                 } else {
 301                         if (ret < 0) {
 302                                 pr_err("%s() returned %d for non S_ISBLK\n",
 303                                                 __func__, ret);
 304                         } else if (ret != data_length) {
 305                                 /*
 306                                  * Short read case:
 307                                  * Probably some one truncate file under us.
 308                                  * We must explicitly zero sg-pages to prevent
 309                                  * expose uninizialized pages to userspace.
 310                                  */
 311                                 if (ret < data_length)
 312                                         ret += iov_iter_zero(data_length - ret, &iter);
 313                                 else
 314                                         ret = -EINVAL;
 315                         }
 316                 }
 317         }
 318         kfree(bvec);
 319         return ret;
 320 }
 321
 322 static sense_reason_t
 323 fd_execute_sync_cache(struct se_cmd *cmd)
 324 {
 325         struct se_device *dev = cmd->se_dev;
 326         struct fd_dev *fd_dev = FD_DEV(dev);
 327         int immed = (cmd->t_task_cdb[1] & 0x2);
 328         loff_t start, end;
 329         int ret;
 330
 331         /*
 332          * If the Immediate bit is set, queue up the GOOD response
 333          * for this SYNCHRONIZE_CACHE op
 334          */
 335         if (immed)
 336                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 337
 338         /*
 339          * Determine if we will be flushing the entire device.
 340          */
 341         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 342                 start = 0;
 343                 end = LLONG_MAX;
 344         } else {
 345                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 346                 if (cmd->data_length)
 347                         end = start + cmd->data_length - 1;
 348                 else
 349                         end = LLONG_MAX;
 350         }
 351
 352         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 353         if (ret != 0)
 354                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 355
 356         if (immed)
 357                 return 0;
 358
 359         if (ret)
 360                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 361         else
 362                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 363
 364         return 0;
 365 }
 366
 367 static sense_reason_t
 368 fd_execute_write_same(struct se_cmd *cmd)
 369 {
 370         struct se_device *se_dev = cmd->se_dev;
 371         struct fd_dev *fd_dev = FD_DEV(se_dev);
 372         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 373         sector_t nolb = sbc_get_write_same_sectors(cmd);
 374         struct iov_iter iter;
 375         struct bio_vec *bvec;
 376         unsigned int len = 0, i;
 377         ssize_t ret;
 378
 379         if (!nolb) {
 380                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 381                 return 0;
 382         }
 383         if (cmd->prot_op) {
 384                 pr_err("WRITE_SAME: Protection information with FILEIO"
 385                        " backends not supported\n");
 386                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 387         }
 388
 389         if (cmd->t_data_nents > 1 ||
 390             cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
 391                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 392                         " block_size: %u\n",
 393                         cmd->t_data_nents,
 394                         cmd->t_data_sg[0].length,
 395                         cmd->se_dev->dev_attrib.block_size);
 396                 return TCM_INVALID_CDB_FIELD;
 397         }
 398
 399         bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
 400         if (!bvec)
 401                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 402
 403         for (i = 0; i < nolb; i++) {
 404                 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
 405                 bvec[i].bv_len = cmd->t_data_sg[0].length;
 406                 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
 407
 408                 len += se_dev->dev_attrib.block_size;
 409         }
 410
 411         iov_iter_bvec(&iter, ITER_BVEC, bvec, nolb, len);
 412         ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos);
 413
 414         kfree(bvec);
 415         if (ret < 0 || ret != len) {
 416                 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
 417                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 418         }
 419
 420         target_complete_cmd(cmd, SAM_STAT_GOOD);
 421         return 0;
 422 }
 423
 424 static int
 425 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
 426                 void *buf, size_t bufsize)
 427 {
 428         struct fd_dev *fd_dev = FD_DEV(se_dev);
 429         struct file *prot_fd = fd_dev->fd_prot_file;
 430         sector_t prot_length, prot;
 431         loff_t pos = lba * se_dev->prot_length;
 432
 433         if (!prot_fd) {
 434                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 435                 return -ENODEV;
 436         }
 437
 438         prot_length = nolb * se_dev->prot_length;
 439
 440         for (prot = 0; prot < prot_length;) {
 441                 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
 442                 ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
 443
 444                 if (ret != len) {
 445                         pr_err("vfs_write to prot file failed: %zd\n", ret);
 446                         return ret < 0 ? ret : -ENODEV;
 447                 }
 448                 prot += ret;
 449         }
 450
 451         return 0;
 452 }
 453
 454 static int
 455 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
 456 {
 457         void *buf;
 458         int rc;
 459
 460         buf = (void *)__get_free_page(GFP_KERNEL);
 461         if (!buf) {
 462                 pr_err("Unable to allocate FILEIO prot buf\n");
 463                 return -ENOMEM;
 464         }
 465         memset(buf, 0xff, PAGE_SIZE);
 466
 467         rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
 468
 469         free_page((unsigned long)buf);
 470
 471         return rc;
 472 }
 473
 474 static sense_reason_t
 475 fd_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
 476 {
 477         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 478         struct inode *inode = file->f_mapping->host;
 479         int ret;
 480
 481         if (cmd->se_dev->dev_attrib.pi_prot_type) {
 482                 ret = fd_do_prot_unmap(cmd, lba, nolb);
 483                 if (ret)
 484                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 485         }
 486
 487         if (S_ISBLK(inode->i_mode)) {
 488                 /* The backend is block device, use discard */
 489                 struct block_device *bdev = inode->i_bdev;
 490                 struct se_device *dev = cmd->se_dev;
 491
 492                 ret = blkdev_issue_discard(bdev,
 493                                            target_to_linux_sector(dev, lba),
 494                                            target_to_linux_sector(dev,  nolb),
 495                                            GFP_KERNEL, 0);
 496                 if (ret < 0) {
 497                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 498                                 ret);
 499                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 500                 }
 501         } else {
 502                 /* The backend is normal file, use fallocate */
 503                 struct se_device *se_dev = cmd->se_dev;
 504                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 505                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 506                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 507
 508                 if (!file->f_op->fallocate)
 509                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 510
 511                 ret = file->f_op->fallocate(file, mode, pos, len);
 512                 if (ret < 0) {
 513                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 514                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 515                 }
 516         }
 517
 518         return 0;
 519 }
 520
 521 static sense_reason_t
 522 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 523               enum dma_data_direction data_direction)
 524 {
 525         struct se_device *dev = cmd->se_dev;
 526         struct fd_dev *fd_dev = FD_DEV(dev);
 527         struct file *file = fd_dev->fd_file;
 528         struct file *pfile = fd_dev->fd_prot_file;
 529         sense_reason_t rc;
 530         int ret = 0;
 531         /*
 532          * We are currently limited by the number of iovecs (2048) per
 533          * single vfs_[writev,readv] call.
 534          */
 535         if (cmd->data_length > FD_MAX_BYTES) {
 536                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 537                        "FD_MAX_BYTES: %u iovec count limitation\n",
 538                         cmd->data_length, FD_MAX_BYTES);
 539                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 540         }
 541         /*
 542          * Call vectorized fileio functions to map struct scatterlist
 543          * physical memory addresses to struct iovec virtual memory.
 544          */
 545         if (data_direction == DMA_FROM_DEVICE) {
 546                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 547                         ret = fd_do_rw(cmd, pfile, dev->prot_length,
 548                                        cmd->t_prot_sg, cmd->t_prot_nents,
 549                                        cmd->prot_length, 0);
 550                         if (ret < 0)
 551                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 552                 }
 553
 554                 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
 555                                sgl, sgl_nents, cmd->data_length, 0);
 556
 557                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type &&
 558                     dev->dev_attrib.pi_prot_verify) {
 559                         u32 sectors = cmd->data_length >>
 560                                         ilog2(dev->dev_attrib.block_size);
 561
 562                         rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
 563                                             0, cmd->t_prot_sg, 0);
 564                         if (rc)
 565                                 return rc;
 566                 }
 567         } else {
 568                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type &&
 569                     dev->dev_attrib.pi_prot_verify) {
 570                         u32 sectors = cmd->data_length >>
 571                                         ilog2(dev->dev_attrib.block_size);
 572
 573                         rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
 574                                             0, cmd->t_prot_sg, 0);
 575                         if (rc)
 576                                 return rc;
 577                 }
 578
 579                 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
 580                                sgl, sgl_nents, cmd->data_length, 1);
 581                 /*
 582                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 583                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 584                  * Allow this to happen independent of WCE=0 setting.
 585                  */
 586                 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
 587                         loff_t start = cmd->t_task_lba *
 588                                 dev->dev_attrib.block_size;
 589                         loff_t end;
 590
 591                         if (cmd->data_length)
 592                                 end = start + cmd->data_length - 1;
 593                         else
 594                                 end = LLONG_MAX;
 595
 596                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 597                 }
 598
 599                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 600                         ret = fd_do_rw(cmd, pfile, dev->prot_length,
 601                                        cmd->t_prot_sg, cmd->t_prot_nents,
 602                                        cmd->prot_length, 1);
 603                         if (ret < 0)
 604                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 605                 }
 606         }
 607
 608         if (ret < 0)
 609                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 610
 611         target_complete_cmd(cmd, SAM_STAT_GOOD);
 612         return 0;
 613 }
 614
 615 enum {
 616         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 617 };
 618
 619 static match_table_t tokens = {
 620         {Opt_fd_dev_name, "fd_dev_name=%s"},
 621         {Opt_fd_dev_size, "fd_dev_size=%s"},
 622         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 623         {Opt_err, NULL}
 624 };
 625
 626 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 627                 const char *page, ssize_t count)
 628 {
 629         struct fd_dev *fd_dev = FD_DEV(dev);
 630         char *orig, *ptr, *arg_p, *opts;
 631         substring_t args[MAX_OPT_ARGS];
 632         int ret = 0, arg, token;
 633
 634         opts = kstrdup(page, GFP_KERNEL);
 635         if (!opts)
 636                 return -ENOMEM;
 637
 638         orig = opts;
 639
 640         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 641                 if (!*ptr)
 642                         continue;
 643
 644                 token = match_token(ptr, tokens, args);
 645                 switch (token) {
 646                 case Opt_fd_dev_name:
 647                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 648                                 FD_MAX_DEV_NAME) == 0) {
 649                                 ret = -EINVAL;
 650                                 break;
 651                         }
 652                         pr_debug("FILEIO: Referencing Path: %s\n",
 653                                         fd_dev->fd_dev_name);
 654                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 655                         break;
 656                 case Opt_fd_dev_size:
 657                         arg_p = match_strdup(&args[0]);
 658                         if (!arg_p) {
 659                                 ret = -ENOMEM;
 660                                 break;
 661                         }
 662                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 663                         kfree(arg_p);
 664                         if (ret < 0) {
 665                                 pr_err("kstrtoull() failed for"
 666                                                 " fd_dev_size=\n");
 667                                 goto out;
 668                         }
 669                         pr_debug("FILEIO: Referencing Size: %llu"
 670                                         " bytes\n", fd_dev->fd_dev_size);
 671                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 672                         break;
 673                 case Opt_fd_buffered_io:
 674                         ret = match_int(args, &arg);
 675                         if (ret)
 676                                 goto out;
 677                         if (arg != 1) {
 678                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 679                                 ret = -EINVAL;
 680                                 goto out;
 681                         }
 682
 683                         pr_debug("FILEIO: Using buffered I/O"
 684                                 " operations for struct fd_dev\n");
 685
 686                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 687                         break;
 688                 default:
 689                         break;
 690                 }
 691         }
 692
 693 out:
 694         kfree(orig);
 695         return (!ret) ? count : ret;
 696 }
 697
 698 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 699 {
 700         struct fd_dev *fd_dev = FD_DEV(dev);
 701         ssize_t bl = 0;
 702
 703         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 704         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 705                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 706                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 707                 "Buffered-WCE" : "O_DSYNC");
 708         return bl;
 709 }
 710
 711 static sector_t fd_get_blocks(struct se_device *dev)
 712 {
 713         struct fd_dev *fd_dev = FD_DEV(dev);
 714         struct file *f = fd_dev->fd_file;
 715         struct inode *i = f->f_mapping->host;
 716         unsigned long long dev_size;
 717         /*
 718          * When using a file that references an underlying struct block_device,
 719          * ensure dev_size is always based on the current inode size in order
 720          * to handle underlying block_device resize operations.
 721          */
 722         if (S_ISBLK(i->i_mode))
 723                 dev_size = i_size_read(i);
 724         else
 725                 dev_size = fd_dev->fd_dev_size;
 726
 727         return div_u64(dev_size - dev->dev_attrib.block_size,
 728                        dev->dev_attrib.block_size);
 729 }
 730
 731 static int fd_init_prot(struct se_device *dev)
 732 {
 733         struct fd_dev *fd_dev = FD_DEV(dev);
 734         struct file *prot_file, *file = fd_dev->fd_file;
 735         struct inode *inode;
 736         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 737         char buf[FD_MAX_DEV_PROT_NAME];
 738
 739         if (!file) {
 740                 pr_err("Unable to locate fd_dev->fd_file\n");
 741                 return -ENODEV;
 742         }
 743
 744         inode = file->f_mapping->host;
 745         if (S_ISBLK(inode->i_mode)) {
 746                 pr_err("FILEIO Protection emulation only supported on"
 747                        " !S_ISBLK\n");
 748                 return -ENOSYS;
 749         }
 750
 751         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 752                 flags &= ~O_DSYNC;
 753
 754         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 755                  fd_dev->fd_dev_name);
 756
 757         prot_file = filp_open(buf, flags, 0600);
 758         if (IS_ERR(prot_file)) {
 759                 pr_err("filp_open(%s) failed\n", buf);
 760                 ret = PTR_ERR(prot_file);
 761                 return ret;
 762         }
 763         fd_dev->fd_prot_file = prot_file;
 764
 765         return 0;
 766 }
 767
 768 static int fd_format_prot(struct se_device *dev)
 769 {
 770         unsigned char *buf;
 771         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 772         int ret;
 773
 774         if (!dev->dev_attrib.pi_prot_type) {
 775                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 776                 return -ENODEV;
 777         }
 778
 779         buf = vzalloc(unit_size);
 780         if (!buf) {
 781                 pr_err("Unable to allocate FILEIO prot buf\n");
 782                 return -ENOMEM;
 783         }
 784
 785         pr_debug("Using FILEIO prot_length: %llu\n",
 786                  (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
 787                                         dev->prot_length);
 788
 789         memset(buf, 0xff, unit_size);
 790         ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
 791                               buf, unit_size);
 792         vfree(buf);
 793         return ret;
 794 }
 795
 796 static void fd_free_prot(struct se_device *dev)
 797 {
 798         struct fd_dev *fd_dev = FD_DEV(dev);
 799
 800         if (!fd_dev->fd_prot_file)
 801                 return;
 802
 803         filp_close(fd_dev->fd_prot_file, NULL);
 804         fd_dev->fd_prot_file = NULL;
 805 }
 806
 807 static struct sbc_ops fd_sbc_ops = {
 808         .execute_rw             = fd_execute_rw,
 809         .execute_sync_cache     = fd_execute_sync_cache,
 810         .execute_write_same     = fd_execute_write_same,
 811         .execute_unmap          = fd_execute_unmap,
 812 };
 813
 814 static sense_reason_t
 815 fd_parse_cdb(struct se_cmd *cmd)
 816 {
 817         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 818 }
 819
 820 static const struct target_backend_ops fileio_ops = {
 821         .name                   = "fileio",
 822         .inquiry_prod           = "FILEIO",
 823         .inquiry_rev            = FD_VERSION,
 824         .owner                  = THIS_MODULE,
 825         .attach_hba             = fd_attach_hba,
 826         .detach_hba             = fd_detach_hba,
 827         .alloc_device           = fd_alloc_device,
 828         .configure_device       = fd_configure_device,
 829         .free_device            = fd_free_device,
 830         .parse_cdb              = fd_parse_cdb,
 831         .set_configfs_dev_params = fd_set_configfs_dev_params,
 832         .show_configfs_dev_params = fd_show_configfs_dev_params,
 833         .get_device_type        = sbc_get_device_type,
 834         .get_blocks             = fd_get_blocks,
 835         .init_prot              = fd_init_prot,
 836         .format_prot            = fd_format_prot,
 837         .free_prot              = fd_free_prot,
 838         .tb_dev_attrib_attrs    = sbc_attrib_attrs,
 839 };
 840
 841 static int __init fileio_module_init(void)
 842 {
 843         return transport_backend_register(&fileio_ops);
 844 }
 845
 846 static void __exit fileio_module_exit(void)
 847 {
 848         target_backend_unregister(&fileio_ops);
 849 }
 850
 851 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
 852 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 853 MODULE_LICENSE("GPL");
 854
 855 module_init(fileio_module_init);
 856 module_exit(fileio_module_exit);