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/falloc.h>
  34 #include <scsi/scsi.h>
  35 #include <scsi/scsi_host.h>
  36 #include <asm/unaligned.h>
  37
  38 #include <target/target_core_base.h>
  39 #include <target/target_core_backend.h>
  40 #include <target/target_core_backend_configfs.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_MOD_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                  * Check if the underlying struct block_device request_queue supports
 166                  * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
 167                  * in ATA and we need to set TPE=1
 168                  */
 169                 if (blk_queue_discard(q)) {
 170                         dev->dev_attrib.max_unmap_lba_count =
 171                                 q->limits.max_discard_sectors;
 172                         /*
 173                          * Currently hardcoded to 1 in Linux/SCSI code..
 174                          */
 175                         dev->dev_attrib.max_unmap_block_desc_count = 1;
 176                         dev->dev_attrib.unmap_granularity =
 177                                 q->limits.discard_granularity >> 9;
 178                         dev->dev_attrib.unmap_granularity_alignment =
 179                                 q->limits.discard_alignment;
 180                         pr_debug("IFILE: BLOCK Discard support available,"
 181                                         " disabled by default\n");
 182                 }
 183                 /*
 184                  * Enable write same emulation for IBLOCK and use 0xFFFF as
 185                  * the smaller WRITE_SAME(10) only has a two-byte block count.
 186                  */
 187                 dev->dev_attrib.max_write_same_len = 0xFFFF;
 188
 189                 if (blk_queue_nonrot(q))
 190                         dev->dev_attrib.is_nonrot = 1;
 191         } else {
 192                 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
 193                         pr_err("FILEIO: Missing fd_dev_size="
 194                                 " parameter, and no backing struct"
 195                                 " block_device\n");
 196                         goto fail;
 197                 }
 198
 199                 fd_dev->fd_block_size = FD_BLOCKSIZE;
 200                 /*
 201                  * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
 202                  */
 203                 dev->dev_attrib.max_unmap_lba_count = 0x2000;
 204                 /*
 205                  * Currently hardcoded to 1 in Linux/SCSI code..
 206                  */
 207                 dev->dev_attrib.max_unmap_block_desc_count = 1;
 208                 dev->dev_attrib.unmap_granularity = 1;
 209                 dev->dev_attrib.unmap_granularity_alignment = 0;
 210
 211                 /*
 212                  * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
 213                  * based upon struct iovec limit for vfs_writev()
 214                  */
 215                 dev->dev_attrib.max_write_same_len = 0x1000;
 216         }
 217
 218         dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
 219         dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES;
 220         dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
 221         dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
 222
 223         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
 224                 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
 225                         " with FDBD_HAS_BUFFERED_IO_WCE\n");
 226                 dev->dev_attrib.emulate_write_cache = 1;
 227         }
 228
 229         fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
 230         fd_dev->fd_queue_depth = dev->queue_depth;
 231
 232         pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
 233                 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
 234                         fd_dev->fd_dev_name, fd_dev->fd_dev_size);
 235
 236         return 0;
 237 fail:
 238         if (fd_dev->fd_file) {
 239                 filp_close(fd_dev->fd_file, NULL);
 240                 fd_dev->fd_file = NULL;
 241         }
 242         return ret;
 243 }
 244
 245 static void fd_free_device(struct se_device *dev)
 246 {
 247         struct fd_dev *fd_dev = FD_DEV(dev);
 248
 249         if (fd_dev->fd_file) {
 250                 filp_close(fd_dev->fd_file, NULL);
 251                 fd_dev->fd_file = NULL;
 252         }
 253
 254         kfree(fd_dev);
 255 }
 256
 257 static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
 258                     u32 block_size, struct scatterlist *sgl,
 259                     u32 sgl_nents, u32 data_length, int is_write)
 260 {
 261         struct scatterlist *sg;
 262         struct iov_iter iter;
 263         struct bio_vec *bvec;
 264         ssize_t len = 0;
 265         loff_t pos = (cmd->t_task_lba * block_size);
 266         int ret = 0, i;
 267
 268         bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
 269         if (!bvec) {
 270                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 271                 return -ENOMEM;
 272         }
 273
 274         for_each_sg(sgl, sg, sgl_nents, i) {
 275                 bvec[i].bv_page = sg_page(sg);
 276                 bvec[i].bv_len = sg->length;
 277                 bvec[i].bv_offset = sg->offset;
 278
 279                 len += sg->length;
 280         }
 281
 282         iov_iter_bvec(&iter, ITER_BVEC, bvec, sgl_nents, len);
 283         if (is_write)
 284                 ret = vfs_iter_write(fd, &iter, &pos);
 285         else
 286                 ret = vfs_iter_read(fd, &iter, &pos);
 287
 288         kfree(bvec);
 289
 290         if (is_write) {
 291                 if (ret < 0 || ret != data_length) {
 292                         pr_err("%s() write returned %d\n", __func__, ret);
 293                         return (ret < 0 ? ret : -EINVAL);
 294                 }
 295         } else {
 296                 /*
 297                  * Return zeros and GOOD status even if the READ did not return
 298                  * the expected virt_size for struct file w/o a backing struct
 299                  * block_device.
 300                  */
 301                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 302                         if (ret < 0 || ret != data_length) {
 303                                 pr_err("%s() returned %d, expecting %u for "
 304                                                 "S_ISBLK\n", __func__, ret,
 305                                                 data_length);
 306                                 return (ret < 0 ? ret : -EINVAL);
 307                         }
 308                 } else {
 309                         if (ret < 0) {
 310                                 pr_err("%s() returned %d for non S_ISBLK\n",
 311                                                 __func__, ret);
 312                                 return ret;
 313                         }
 314                 }
 315         }
 316         return 1;
 317 }
 318
 319 static sense_reason_t
 320 fd_execute_sync_cache(struct se_cmd *cmd)
 321 {
 322         struct se_device *dev = cmd->se_dev;
 323         struct fd_dev *fd_dev = FD_DEV(dev);
 324         int immed = (cmd->t_task_cdb[1] & 0x2);
 325         loff_t start, end;
 326         int ret;
 327
 328         /*
 329          * If the Immediate bit is set, queue up the GOOD response
 330          * for this SYNCHRONIZE_CACHE op
 331          */
 332         if (immed)
 333                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 334
 335         /*
 336          * Determine if we will be flushing the entire device.
 337          */
 338         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 339                 start = 0;
 340                 end = LLONG_MAX;
 341         } else {
 342                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 343                 if (cmd->data_length)
 344                         end = start + cmd->data_length - 1;
 345                 else
 346                         end = LLONG_MAX;
 347         }
 348
 349         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 350         if (ret != 0)
 351                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 352
 353         if (immed)
 354                 return 0;
 355
 356         if (ret)
 357                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 358         else
 359                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 360
 361         return 0;
 362 }
 363
 364 static sense_reason_t
 365 fd_execute_write_same(struct se_cmd *cmd)
 366 {
 367         struct se_device *se_dev = cmd->se_dev;
 368         struct fd_dev *fd_dev = FD_DEV(se_dev);
 369         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 370         sector_t nolb = sbc_get_write_same_sectors(cmd);
 371         struct iov_iter iter;
 372         struct bio_vec *bvec;
 373         unsigned int len = 0, i;
 374         ssize_t ret;
 375
 376         if (!nolb) {
 377                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 378                 return 0;
 379         }
 380         if (cmd->prot_op) {
 381                 pr_err("WRITE_SAME: Protection information with FILEIO"
 382                        " backends not supported\n");
 383                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 384         }
 385
 386         if (cmd->t_data_nents > 1 ||
 387             cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
 388                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 389                         " block_size: %u\n",
 390                         cmd->t_data_nents,
 391                         cmd->t_data_sg[0].length,
 392                         cmd->se_dev->dev_attrib.block_size);
 393                 return TCM_INVALID_CDB_FIELD;
 394         }
 395
 396         bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
 397         if (!bvec)
 398                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 399
 400         for (i = 0; i < nolb; i++) {
 401                 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
 402                 bvec[i].bv_len = cmd->t_data_sg[0].length;
 403                 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
 404
 405                 len += se_dev->dev_attrib.block_size;
 406         }
 407
 408         iov_iter_bvec(&iter, ITER_BVEC, bvec, nolb, len);
 409         ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos);
 410
 411         kfree(bvec);
 412         if (ret < 0 || ret != len) {
 413                 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
 414                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 415         }
 416
 417         target_complete_cmd(cmd, SAM_STAT_GOOD);
 418         return 0;
 419 }
 420
 421 static int
 422 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
 423                 void *buf, size_t bufsize)
 424 {
 425         struct fd_dev *fd_dev = FD_DEV(se_dev);
 426         struct file *prot_fd = fd_dev->fd_prot_file;
 427         sector_t prot_length, prot;
 428         loff_t pos = lba * se_dev->prot_length;
 429
 430         if (!prot_fd) {
 431                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 432                 return -ENODEV;
 433         }
 434
 435         prot_length = nolb * se_dev->prot_length;
 436
 437         for (prot = 0; prot < prot_length;) {
 438                 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
 439                 ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
 440
 441                 if (ret != len) {
 442                         pr_err("vfs_write to prot file failed: %zd\n", ret);
 443                         return ret < 0 ? ret : -ENODEV;
 444                 }
 445                 prot += ret;
 446         }
 447
 448         return 0;
 449 }
 450
 451 static int
 452 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
 453 {
 454         void *buf;
 455         int rc;
 456
 457         buf = (void *)__get_free_page(GFP_KERNEL);
 458         if (!buf) {
 459                 pr_err("Unable to allocate FILEIO prot buf\n");
 460                 return -ENOMEM;
 461         }
 462         memset(buf, 0xff, PAGE_SIZE);
 463
 464         rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
 465
 466         free_page((unsigned long)buf);
 467
 468         return rc;
 469 }
 470
 471 static sense_reason_t
 472 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 473 {
 474         struct file *file = priv;
 475         struct inode *inode = file->f_mapping->host;
 476         int ret;
 477
 478         if (cmd->se_dev->dev_attrib.pi_prot_type) {
 479                 ret = fd_do_prot_unmap(cmd, lba, nolb);
 480                 if (ret)
 481                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 482         }
 483
 484         if (S_ISBLK(inode->i_mode)) {
 485                 /* The backend is block device, use discard */
 486                 struct block_device *bdev = inode->i_bdev;
 487
 488                 ret = blkdev_issue_discard(bdev, lba,
 489                                 nolb, GFP_KERNEL, 0);
 490                 if (ret < 0) {
 491                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 492                                 ret);
 493                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 494                 }
 495         } else {
 496                 /* The backend is normal file, use fallocate */
 497                 struct se_device *se_dev = cmd->se_dev;
 498                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 499                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 500                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 501
 502                 if (!file->f_op->fallocate)
 503                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 504
 505                 ret = file->f_op->fallocate(file, mode, pos, len);
 506                 if (ret < 0) {
 507                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 508                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 509                 }
 510         }
 511
 512         return 0;
 513 }
 514
 515 static sense_reason_t
 516 fd_execute_write_same_unmap(struct se_cmd *cmd)
 517 {
 518         struct se_device *se_dev = cmd->se_dev;
 519         struct fd_dev *fd_dev = FD_DEV(se_dev);
 520         struct file *file = fd_dev->fd_file;
 521         sector_t lba = cmd->t_task_lba;
 522         sector_t nolb = sbc_get_write_same_sectors(cmd);
 523         sense_reason_t ret;
 524
 525         if (!nolb) {
 526                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 527                 return 0;
 528         }
 529
 530         ret = fd_do_unmap(cmd, file, lba, nolb);
 531         if (ret)
 532                 return ret;
 533
 534         target_complete_cmd(cmd, GOOD);
 535         return 0;
 536 }
 537
 538 static sense_reason_t
 539 fd_execute_unmap(struct se_cmd *cmd)
 540 {
 541         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 542
 543         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 544 }
 545
 546 static sense_reason_t
 547 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 548               enum dma_data_direction data_direction)
 549 {
 550         struct se_device *dev = cmd->se_dev;
 551         struct fd_dev *fd_dev = FD_DEV(dev);
 552         struct file *file = fd_dev->fd_file;
 553         struct file *pfile = fd_dev->fd_prot_file;
 554         sense_reason_t rc;
 555         int ret = 0;
 556         /*
 557          * We are currently limited by the number of iovecs (2048) per
 558          * single vfs_[writev,readv] call.
 559          */
 560         if (cmd->data_length > FD_MAX_BYTES) {
 561                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 562                        "FD_MAX_BYTES: %u iovec count limitiation\n",
 563                         cmd->data_length, FD_MAX_BYTES);
 564                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 565         }
 566         /*
 567          * Call vectorized fileio functions to map struct scatterlist
 568          * physical memory addresses to struct iovec virtual memory.
 569          */
 570         if (data_direction == DMA_FROM_DEVICE) {
 571                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 572                         ret = fd_do_rw(cmd, pfile, dev->prot_length,
 573                                        cmd->t_prot_sg, cmd->t_prot_nents,
 574                                        cmd->prot_length, 0);
 575                         if (ret < 0)
 576                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 577                 }
 578
 579                 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
 580                                sgl, sgl_nents, cmd->data_length, 0);
 581
 582                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 583                         u32 sectors = cmd->data_length >>
 584                                         ilog2(dev->dev_attrib.block_size);
 585
 586                         rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
 587                                             0, cmd->t_prot_sg, 0);
 588                         if (rc)
 589                                 return rc;
 590                 }
 591         } else {
 592                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 593                         u32 sectors = cmd->data_length >>
 594                                         ilog2(dev->dev_attrib.block_size);
 595
 596                         rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
 597                                             0, cmd->t_prot_sg, 0);
 598                         if (rc)
 599                                 return rc;
 600                 }
 601
 602                 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
 603                                sgl, sgl_nents, cmd->data_length, 1);
 604                 /*
 605                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 606                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 607                  * Allow this to happen independent of WCE=0 setting.
 608                  */
 609                 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
 610                         loff_t start = cmd->t_task_lba *
 611                                 dev->dev_attrib.block_size;
 612                         loff_t end;
 613
 614                         if (cmd->data_length)
 615                                 end = start + cmd->data_length - 1;
 616                         else
 617                                 end = LLONG_MAX;
 618
 619                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 620                 }
 621
 622                 if (ret > 0 && 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, 1);
 626                         if (ret < 0)
 627                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 628                 }
 629         }
 630
 631         if (ret < 0)
 632                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 633
 634         if (ret)
 635                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 636         return 0;
 637 }
 638
 639 enum {
 640         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 641 };
 642
 643 static match_table_t tokens = {
 644         {Opt_fd_dev_name, "fd_dev_name=%s"},
 645         {Opt_fd_dev_size, "fd_dev_size=%s"},
 646         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 647         {Opt_err, NULL}
 648 };
 649
 650 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 651                 const char *page, ssize_t count)
 652 {
 653         struct fd_dev *fd_dev = FD_DEV(dev);
 654         char *orig, *ptr, *arg_p, *opts;
 655         substring_t args[MAX_OPT_ARGS];
 656         int ret = 0, arg, token;
 657
 658         opts = kstrdup(page, GFP_KERNEL);
 659         if (!opts)
 660                 return -ENOMEM;
 661
 662         orig = opts;
 663
 664         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 665                 if (!*ptr)
 666                         continue;
 667
 668                 token = match_token(ptr, tokens, args);
 669                 switch (token) {
 670                 case Opt_fd_dev_name:
 671                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 672                                 FD_MAX_DEV_NAME) == 0) {
 673                                 ret = -EINVAL;
 674                                 break;
 675                         }
 676                         pr_debug("FILEIO: Referencing Path: %s\n",
 677                                         fd_dev->fd_dev_name);
 678                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 679                         break;
 680                 case Opt_fd_dev_size:
 681                         arg_p = match_strdup(&args[0]);
 682                         if (!arg_p) {
 683                                 ret = -ENOMEM;
 684                                 break;
 685                         }
 686                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 687                         kfree(arg_p);
 688                         if (ret < 0) {
 689                                 pr_err("kstrtoull() failed for"
 690                                                 " fd_dev_size=\n");
 691                                 goto out;
 692                         }
 693                         pr_debug("FILEIO: Referencing Size: %llu"
 694                                         " bytes\n", fd_dev->fd_dev_size);
 695                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 696                         break;
 697                 case Opt_fd_buffered_io:
 698                         ret = match_int(args, &arg);
 699                         if (ret)
 700                                 goto out;
 701                         if (arg != 1) {
 702                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 703                                 ret = -EINVAL;
 704                                 goto out;
 705                         }
 706
 707                         pr_debug("FILEIO: Using buffered I/O"
 708                                 " operations for struct fd_dev\n");
 709
 710                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 711                         break;
 712                 default:
 713                         break;
 714                 }
 715         }
 716
 717 out:
 718         kfree(orig);
 719         return (!ret) ? count : ret;
 720 }
 721
 722 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 723 {
 724         struct fd_dev *fd_dev = FD_DEV(dev);
 725         ssize_t bl = 0;
 726
 727         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 728         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 729                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 730                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 731                 "Buffered-WCE" : "O_DSYNC");
 732         return bl;
 733 }
 734
 735 static sector_t fd_get_blocks(struct se_device *dev)
 736 {
 737         struct fd_dev *fd_dev = FD_DEV(dev);
 738         struct file *f = fd_dev->fd_file;
 739         struct inode *i = f->f_mapping->host;
 740         unsigned long long dev_size;
 741         /*
 742          * When using a file that references an underlying struct block_device,
 743          * ensure dev_size is always based on the current inode size in order
 744          * to handle underlying block_device resize operations.
 745          */
 746         if (S_ISBLK(i->i_mode))
 747                 dev_size = i_size_read(i);
 748         else
 749                 dev_size = fd_dev->fd_dev_size;
 750
 751         return div_u64(dev_size - dev->dev_attrib.block_size,
 752                        dev->dev_attrib.block_size);
 753 }
 754
 755 static int fd_init_prot(struct se_device *dev)
 756 {
 757         struct fd_dev *fd_dev = FD_DEV(dev);
 758         struct file *prot_file, *file = fd_dev->fd_file;
 759         struct inode *inode;
 760         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 761         char buf[FD_MAX_DEV_PROT_NAME];
 762
 763         if (!file) {
 764                 pr_err("Unable to locate fd_dev->fd_file\n");
 765                 return -ENODEV;
 766         }
 767
 768         inode = file->f_mapping->host;
 769         if (S_ISBLK(inode->i_mode)) {
 770                 pr_err("FILEIO Protection emulation only supported on"
 771                        " !S_ISBLK\n");
 772                 return -ENOSYS;
 773         }
 774
 775         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 776                 flags &= ~O_DSYNC;
 777
 778         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 779                  fd_dev->fd_dev_name);
 780
 781         prot_file = filp_open(buf, flags, 0600);
 782         if (IS_ERR(prot_file)) {
 783                 pr_err("filp_open(%s) failed\n", buf);
 784                 ret = PTR_ERR(prot_file);
 785                 return ret;
 786         }
 787         fd_dev->fd_prot_file = prot_file;
 788
 789         return 0;
 790 }
 791
 792 static int fd_format_prot(struct se_device *dev)
 793 {
 794         unsigned char *buf;
 795         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 796         int ret;
 797
 798         if (!dev->dev_attrib.pi_prot_type) {
 799                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 800                 return -ENODEV;
 801         }
 802
 803         buf = vzalloc(unit_size);
 804         if (!buf) {
 805                 pr_err("Unable to allocate FILEIO prot buf\n");
 806                 return -ENOMEM;
 807         }
 808
 809         pr_debug("Using FILEIO prot_length: %llu\n",
 810                  (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
 811                                         dev->prot_length);
 812
 813         memset(buf, 0xff, unit_size);
 814         ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
 815                               buf, unit_size);
 816         vfree(buf);
 817         return ret;
 818 }
 819
 820 static void fd_free_prot(struct se_device *dev)
 821 {
 822         struct fd_dev *fd_dev = FD_DEV(dev);
 823
 824         if (!fd_dev->fd_prot_file)
 825                 return;
 826
 827         filp_close(fd_dev->fd_prot_file, NULL);
 828         fd_dev->fd_prot_file = NULL;
 829 }
 830
 831 static struct sbc_ops fd_sbc_ops = {
 832         .execute_rw             = fd_execute_rw,
 833         .execute_sync_cache     = fd_execute_sync_cache,
 834         .execute_write_same     = fd_execute_write_same,
 835         .execute_write_same_unmap = fd_execute_write_same_unmap,
 836         .execute_unmap          = fd_execute_unmap,
 837 };
 838
 839 static sense_reason_t
 840 fd_parse_cdb(struct se_cmd *cmd)
 841 {
 842         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 843 }
 844
 845 DEF_TB_DEFAULT_ATTRIBS(fileio);
 846
 847 static struct configfs_attribute *fileio_backend_dev_attrs[] = {
 848         &fileio_dev_attrib_emulate_model_alias.attr,
 849         &fileio_dev_attrib_emulate_dpo.attr,
 850         &fileio_dev_attrib_emulate_fua_write.attr,
 851         &fileio_dev_attrib_emulate_fua_read.attr,
 852         &fileio_dev_attrib_emulate_write_cache.attr,
 853         &fileio_dev_attrib_emulate_ua_intlck_ctrl.attr,
 854         &fileio_dev_attrib_emulate_tas.attr,
 855         &fileio_dev_attrib_emulate_tpu.attr,
 856         &fileio_dev_attrib_emulate_tpws.attr,
 857         &fileio_dev_attrib_emulate_caw.attr,
 858         &fileio_dev_attrib_emulate_3pc.attr,
 859         &fileio_dev_attrib_pi_prot_type.attr,
 860         &fileio_dev_attrib_hw_pi_prot_type.attr,
 861         &fileio_dev_attrib_pi_prot_format.attr,
 862         &fileio_dev_attrib_enforce_pr_isids.attr,
 863         &fileio_dev_attrib_is_nonrot.attr,
 864         &fileio_dev_attrib_emulate_rest_reord.attr,
 865         &fileio_dev_attrib_force_pr_aptpl.attr,
 866         &fileio_dev_attrib_hw_block_size.attr,
 867         &fileio_dev_attrib_block_size.attr,
 868         &fileio_dev_attrib_hw_max_sectors.attr,
 869         &fileio_dev_attrib_optimal_sectors.attr,
 870         &fileio_dev_attrib_hw_queue_depth.attr,
 871         &fileio_dev_attrib_queue_depth.attr,
 872         &fileio_dev_attrib_max_unmap_lba_count.attr,
 873         &fileio_dev_attrib_max_unmap_block_desc_count.attr,
 874         &fileio_dev_attrib_unmap_granularity.attr,
 875         &fileio_dev_attrib_unmap_granularity_alignment.attr,
 876         &fileio_dev_attrib_max_write_same_len.attr,
 877         NULL,
 878 };
 879
 880 static const struct target_backend_ops fileio_ops = {
 881         .name                   = "fileio",
 882         .inquiry_prod           = "FILEIO",
 883         .inquiry_rev            = FD_VERSION,
 884         .owner                  = THIS_MODULE,
 885         .attach_hba             = fd_attach_hba,
 886         .detach_hba             = fd_detach_hba,
 887         .alloc_device           = fd_alloc_device,
 888         .configure_device       = fd_configure_device,
 889         .free_device            = fd_free_device,
 890         .parse_cdb              = fd_parse_cdb,
 891         .set_configfs_dev_params = fd_set_configfs_dev_params,
 892         .show_configfs_dev_params = fd_show_configfs_dev_params,
 893         .get_device_type        = sbc_get_device_type,
 894         .get_blocks             = fd_get_blocks,
 895         .init_prot              = fd_init_prot,
 896         .format_prot            = fd_format_prot,
 897         .free_prot              = fd_free_prot,
 898         .tb_dev_attrib_attrs    = fileio_backend_dev_attrs,
 899 };
 900
 901 static int __init fileio_module_init(void)
 902 {
 903         return transport_backend_register(&fileio_ops);
 904 }
 905
 906 static void __exit fileio_module_exit(void)
 907 {
 908         target_backend_unregister(&fileio_ops);
 909 }
 910
 911 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
 912 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 913 MODULE_LICENSE("GPL");
 914
 915 module_init(fileio_module_init);
 916 module_exit(fileio_module_exit);