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 2005-2012 RisingTide Systems LLC.
   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
  41 #include "target_core_file.h"
  42
  43 static inline struct fd_dev *FD_DEV(struct se_device *dev)
  44 {
  45         return container_of(dev, struct fd_dev, dev);
  46 }
  47
  48 /*      fd_attach_hba(): (Part of se_subsystem_api_t template)
  49  *
  50  *
  51  */
  52 static int fd_attach_hba(struct se_hba *hba, u32 host_id)
  53 {
  54         struct fd_host *fd_host;
  55
  56         fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
  57         if (!fd_host) {
  58                 pr_err("Unable to allocate memory for struct fd_host\n");
  59                 return -ENOMEM;
  60         }
  61
  62         fd_host->fd_host_id = host_id;
  63
  64         hba->hba_ptr = fd_host;
  65
  66         pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
  67                 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
  68                 TARGET_CORE_MOD_VERSION);
  69         pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic"
  70                 " MaxSectors: %u\n",
  71                 hba->hba_id, fd_host->fd_host_id, FD_MAX_SECTORS);
  72
  73         return 0;
  74 }
  75
  76 static void fd_detach_hba(struct se_hba *hba)
  77 {
  78         struct fd_host *fd_host = hba->hba_ptr;
  79
  80         pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
  81                 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
  82
  83         kfree(fd_host);
  84         hba->hba_ptr = NULL;
  85 }
  86
  87 static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
  88 {
  89         struct fd_dev *fd_dev;
  90         struct fd_host *fd_host = hba->hba_ptr;
  91
  92         fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
  93         if (!fd_dev) {
  94                 pr_err("Unable to allocate memory for struct fd_dev\n");
  95                 return NULL;
  96         }
  97
  98         fd_dev->fd_host = fd_host;
  99
 100         pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
 101
 102         return &fd_dev->dev;
 103 }
 104
 105 static int fd_configure_device(struct se_device *dev)
 106 {
 107         struct fd_dev *fd_dev = FD_DEV(dev);
 108         struct fd_host *fd_host = dev->se_hba->hba_ptr;
 109         struct file *file;
 110         struct inode *inode = NULL;
 111         int flags, ret = -EINVAL;
 112
 113         if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
 114                 pr_err("Missing fd_dev_name=\n");
 115                 return -EINVAL;
 116         }
 117
 118         /*
 119          * Use O_DSYNC by default instead of O_SYNC to forgo syncing
 120          * of pure timestamp updates.
 121          */
 122         flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 123
 124         /*
 125          * Optionally allow fd_buffered_io=1 to be enabled for people
 126          * who want use the fs buffer cache as an WriteCache mechanism.
 127          *
 128          * This means that in event of a hard failure, there is a risk
 129          * of silent data-loss if the SCSI client has *not* performed a
 130          * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
 131          * to write-out the entire device cache.
 132          */
 133         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
 134                 pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
 135                 flags &= ~O_DSYNC;
 136         }
 137
 138         file = filp_open(fd_dev->fd_dev_name, flags, 0600);
 139         if (IS_ERR(file)) {
 140                 pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
 141                 ret = PTR_ERR(file);
 142                 goto fail;
 143         }
 144         fd_dev->fd_file = file;
 145         /*
 146          * If using a block backend with this struct file, we extract
 147          * fd_dev->fd_[block,dev]_size from struct block_device.
 148          *
 149          * Otherwise, we use the passed fd_size= from configfs
 150          */
 151         inode = file->f_mapping->host;
 152         if (S_ISBLK(inode->i_mode)) {
 153                 struct request_queue *q = bdev_get_queue(inode->i_bdev);
 154                 unsigned long long dev_size;
 155
 156                 dev->dev_attrib.hw_block_size =
 157                         bdev_logical_block_size(inode->i_bdev);
 158                 dev->dev_attrib.hw_max_sectors = queue_max_hw_sectors(q);
 159
 160                 /*
 161                  * Determine the number of bytes from i_size_read() minus
 162                  * one (1) logical sector from underlying struct block_device
 163                  */
 164                 dev_size = (i_size_read(file->f_mapping->host) -
 165                                        fd_dev->fd_block_size);
 166
 167                 pr_debug("FILEIO: Using size: %llu bytes from struct"
 168                         " block_device blocks: %llu logical_block_size: %d\n",
 169                         dev_size, div_u64(dev_size, fd_dev->fd_block_size),
 170                         fd_dev->fd_block_size);
 171                 /*
 172                  * Check if the underlying struct block_device request_queue supports
 173                  * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
 174                  * in ATA and we need to set TPE=1
 175                  */
 176                 if (blk_queue_discard(q)) {
 177                         dev->dev_attrib.max_unmap_lba_count =
 178                                 q->limits.max_discard_sectors;
 179                         /*
 180                          * Currently hardcoded to 1 in Linux/SCSI code..
 181                          */
 182                         dev->dev_attrib.max_unmap_block_desc_count = 1;
 183                         dev->dev_attrib.unmap_granularity =
 184                                 q->limits.discard_granularity >> 9;
 185                         dev->dev_attrib.unmap_granularity_alignment =
 186                                 q->limits.discard_alignment;
 187                         pr_debug("IFILE: BLOCK Discard support available,"
 188                                         " disabled by default\n");
 189                 }
 190                 /*
 191                  * Enable write same emulation for IBLOCK and use 0xFFFF as
 192                  * the smaller WRITE_SAME(10) only has a two-byte block count.
 193                  */
 194                 dev->dev_attrib.max_write_same_len = 0xFFFF;
 195
 196                 if (blk_queue_nonrot(q))
 197                         dev->dev_attrib.is_nonrot = 1;
 198         } else {
 199                 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
 200                         pr_err("FILEIO: Missing fd_dev_size="
 201                                 " parameter, and no backing struct"
 202                                 " block_device\n");
 203                         goto fail;
 204                 }
 205
 206                 dev->dev_attrib.hw_block_size = FD_BLOCKSIZE;
 207                 dev->dev_attrib.hw_max_sectors = FD_MAX_SECTORS;
 208
 209                 /*
 210                  * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
 211                  */
 212                 dev->dev_attrib.max_unmap_lba_count = 0x2000;
 213                 /*
 214                  * Currently hardcoded to 1 in Linux/SCSI code..
 215                  */
 216                 dev->dev_attrib.max_unmap_block_desc_count = 1;
 217                 dev->dev_attrib.unmap_granularity = 1;
 218                 dev->dev_attrib.unmap_granularity_alignment = 0;
 219
 220                 /*
 221                  * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
 222                  * based upon struct iovec limit for vfs_writev()
 223                  */
 224                 dev->dev_attrib.max_write_same_len = 0x1000;
 225         }
 226
 227         fd_dev->fd_block_size = dev->dev_attrib.hw_block_size;
 228
 229         dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
 230
 231         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
 232                 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
 233                         " with FDBD_HAS_BUFFERED_IO_WCE\n");
 234                 dev->dev_attrib.emulate_write_cache = 1;
 235         }
 236
 237         fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
 238         fd_dev->fd_queue_depth = dev->queue_depth;
 239
 240         pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
 241                 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
 242                         fd_dev->fd_dev_name, fd_dev->fd_dev_size);
 243
 244         return 0;
 245 fail:
 246         if (fd_dev->fd_file) {
 247                 filp_close(fd_dev->fd_file, NULL);
 248                 fd_dev->fd_file = NULL;
 249         }
 250         return ret;
 251 }
 252
 253 static void fd_free_device(struct se_device *dev)
 254 {
 255         struct fd_dev *fd_dev = FD_DEV(dev);
 256
 257         if (fd_dev->fd_file) {
 258                 filp_close(fd_dev->fd_file, NULL);
 259                 fd_dev->fd_file = NULL;
 260         }
 261
 262         kfree(fd_dev);
 263 }
 264
 265 static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
 266                 u32 sgl_nents, int is_write)
 267 {
 268         struct se_device *se_dev = cmd->se_dev;
 269         struct fd_dev *dev = FD_DEV(se_dev);
 270         struct file *fd = dev->fd_file;
 271         struct scatterlist *sg;
 272         struct iovec *iov;
 273         mm_segment_t old_fs;
 274         loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
 275         int ret = 0, i;
 276
 277         iov = kzalloc(sizeof(struct iovec) * sgl_nents, GFP_KERNEL);
 278         if (!iov) {
 279                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 280                 return -ENOMEM;
 281         }
 282
 283         for_each_sg(sgl, sg, sgl_nents, i) {
 284                 iov[i].iov_len = sg->length;
 285                 iov[i].iov_base = kmap(sg_page(sg)) + sg->offset;
 286         }
 287
 288         old_fs = get_fs();
 289         set_fs(get_ds());
 290
 291         if (is_write)
 292                 ret = vfs_writev(fd, &iov[0], sgl_nents, &pos);
 293         else
 294                 ret = vfs_readv(fd, &iov[0], sgl_nents, &pos);
 295
 296         set_fs(old_fs);
 297
 298         for_each_sg(sgl, sg, sgl_nents, i)
 299                 kunmap(sg_page(sg));
 300
 301         kfree(iov);
 302
 303         if (is_write) {
 304                 if (ret < 0 || ret != cmd->data_length) {
 305                         pr_err("%s() write returned %d\n", __func__, ret);
 306                         return (ret < 0 ? ret : -EINVAL);
 307                 }
 308         } else {
 309                 /*
 310                  * Return zeros and GOOD status even if the READ did not return
 311                  * the expected virt_size for struct file w/o a backing struct
 312                  * block_device.
 313                  */
 314                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 315                         if (ret < 0 || ret != cmd->data_length) {
 316                                 pr_err("%s() returned %d, expecting %u for "
 317                                                 "S_ISBLK\n", __func__, ret,
 318                                                 cmd->data_length);
 319                                 return (ret < 0 ? ret : -EINVAL);
 320                         }
 321                 } else {
 322                         if (ret < 0) {
 323                                 pr_err("%s() returned %d for non S_ISBLK\n",
 324                                                 __func__, ret);
 325                                 return ret;
 326                         }
 327                 }
 328         }
 329         return 1;
 330 }
 331
 332 static sense_reason_t
 333 fd_execute_sync_cache(struct se_cmd *cmd)
 334 {
 335         struct se_device *dev = cmd->se_dev;
 336         struct fd_dev *fd_dev = FD_DEV(dev);
 337         int immed = (cmd->t_task_cdb[1] & 0x2);
 338         loff_t start, end;
 339         int ret;
 340
 341         /*
 342          * If the Immediate bit is set, queue up the GOOD response
 343          * for this SYNCHRONIZE_CACHE op
 344          */
 345         if (immed)
 346                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 347
 348         /*
 349          * Determine if we will be flushing the entire device.
 350          */
 351         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 352                 start = 0;
 353                 end = LLONG_MAX;
 354         } else {
 355                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 356                 if (cmd->data_length)
 357                         end = start + cmd->data_length;
 358                 else
 359                         end = LLONG_MAX;
 360         }
 361
 362         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 363         if (ret != 0)
 364                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 365
 366         if (immed)
 367                 return 0;
 368
 369         if (ret)
 370                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 371         else
 372                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 373
 374         return 0;
 375 }
 376
 377 static unsigned char *
 378 fd_setup_write_same_buf(struct se_cmd *cmd, struct scatterlist *sg,
 379                     unsigned int len)
 380 {
 381         struct se_device *se_dev = cmd->se_dev;
 382         unsigned int block_size = se_dev->dev_attrib.block_size;
 383         unsigned int i = 0, end;
 384         unsigned char *buf, *p, *kmap_buf;
 385
 386         buf = kzalloc(min_t(unsigned int, len, PAGE_SIZE), GFP_KERNEL);
 387         if (!buf) {
 388                 pr_err("Unable to allocate fd_execute_write_same buf\n");
 389                 return NULL;
 390         }
 391
 392         kmap_buf = kmap(sg_page(sg)) + sg->offset;
 393         if (!kmap_buf) {
 394                 pr_err("kmap() failed in fd_setup_write_same\n");
 395                 kfree(buf);
 396                 return NULL;
 397         }
 398         /*
 399          * Fill local *buf to contain multiple WRITE_SAME blocks up to
 400          * min(len, PAGE_SIZE)
 401          */
 402         p = buf;
 403         end = min_t(unsigned int, len, PAGE_SIZE);
 404
 405         while (i < end) {
 406                 memcpy(p, kmap_buf, block_size);
 407
 408                 i += block_size;
 409                 p += block_size;
 410         }
 411         kunmap(sg_page(sg));
 412
 413         return buf;
 414 }
 415
 416 static sense_reason_t
 417 fd_execute_write_same(struct se_cmd *cmd)
 418 {
 419         struct se_device *se_dev = cmd->se_dev;
 420         struct fd_dev *fd_dev = FD_DEV(se_dev);
 421         struct file *f = fd_dev->fd_file;
 422         struct scatterlist *sg;
 423         struct iovec *iov;
 424         mm_segment_t old_fs;
 425         sector_t nolb = sbc_get_write_same_sectors(cmd);
 426         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 427         unsigned int len, len_tmp, iov_num;
 428         int i, rc;
 429         unsigned char *buf;
 430
 431         if (!nolb) {
 432                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 433                 return 0;
 434         }
 435         sg = &cmd->t_data_sg[0];
 436
 437         if (cmd->t_data_nents > 1 ||
 438             sg->length != cmd->se_dev->dev_attrib.block_size) {
 439                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 440                         " block_size: %u\n", cmd->t_data_nents, sg->length,
 441                         cmd->se_dev->dev_attrib.block_size);
 442                 return TCM_INVALID_CDB_FIELD;
 443         }
 444
 445         len = len_tmp = nolb * se_dev->dev_attrib.block_size;
 446         iov_num = DIV_ROUND_UP(len, PAGE_SIZE);
 447
 448         buf = fd_setup_write_same_buf(cmd, sg, len);
 449         if (!buf)
 450                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 451
 452         iov = vzalloc(sizeof(struct iovec) * iov_num);
 453         if (!iov) {
 454                 pr_err("Unable to allocate fd_execute_write_same iovecs\n");
 455                 kfree(buf);
 456                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 457         }
 458         /*
 459          * Map the single fabric received scatterlist block now populated
 460          * in *buf into each iovec for I/O submission.
 461          */
 462         for (i = 0; i < iov_num; i++) {
 463                 iov[i].iov_base = buf;
 464                 iov[i].iov_len = min_t(unsigned int, len_tmp, PAGE_SIZE);
 465                 len_tmp -= iov[i].iov_len;
 466         }
 467
 468         old_fs = get_fs();
 469         set_fs(get_ds());
 470         rc = vfs_writev(f, &iov[0], iov_num, &pos);
 471         set_fs(old_fs);
 472
 473         vfree(iov);
 474         kfree(buf);
 475
 476         if (rc < 0 || rc != len) {
 477                 pr_err("vfs_writev() returned %d for write same\n", rc);
 478                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 479         }
 480
 481         target_complete_cmd(cmd, SAM_STAT_GOOD);
 482         return 0;
 483 }
 484
 485 static sense_reason_t
 486 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 487 {
 488         struct file *file = priv;
 489         struct inode *inode = file->f_mapping->host;
 490         int ret;
 491
 492         if (S_ISBLK(inode->i_mode)) {
 493                 /* The backend is block device, use discard */
 494                 struct block_device *bdev = inode->i_bdev;
 495
 496                 ret = blkdev_issue_discard(bdev, lba,
 497                                 nolb, GFP_KERNEL, 0);
 498                 if (ret < 0) {
 499                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 500                                 ret);
 501                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 502                 }
 503         } else {
 504                 /* The backend is normal file, use fallocate */
 505                 struct se_device *se_dev = cmd->se_dev;
 506                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 507                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 508                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 509
 510                 if (!file->f_op->fallocate)
 511                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 512
 513                 ret = file->f_op->fallocate(file, mode, pos, len);
 514                 if (ret < 0) {
 515                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 516                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 517                 }
 518         }
 519
 520         return 0;
 521 }
 522
 523 static sense_reason_t
 524 fd_execute_write_same_unmap(struct se_cmd *cmd)
 525 {
 526         struct se_device *se_dev = cmd->se_dev;
 527         struct fd_dev *fd_dev = FD_DEV(se_dev);
 528         struct file *file = fd_dev->fd_file;
 529         sector_t lba = cmd->t_task_lba;
 530         sector_t nolb = sbc_get_write_same_sectors(cmd);
 531         int ret;
 532
 533         if (!nolb) {
 534                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 535                 return 0;
 536         }
 537
 538         ret = fd_do_unmap(cmd, file, lba, nolb);
 539         if (ret)
 540                 return ret;
 541
 542         target_complete_cmd(cmd, GOOD);
 543         return 0;
 544 }
 545
 546 static sense_reason_t
 547 fd_execute_unmap(struct se_cmd *cmd)
 548 {
 549         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 550
 551         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 552 }
 553
 554 static sense_reason_t
 555 fd_execute_rw(struct se_cmd *cmd)
 556 {
 557         struct scatterlist *sgl = cmd->t_data_sg;
 558         u32 sgl_nents = cmd->t_data_nents;
 559         enum dma_data_direction data_direction = cmd->data_direction;
 560         struct se_device *dev = cmd->se_dev;
 561         int ret = 0;
 562
 563         /*
 564          * Call vectorized fileio functions to map struct scatterlist
 565          * physical memory addresses to struct iovec virtual memory.
 566          */
 567         if (data_direction == DMA_FROM_DEVICE) {
 568                 ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
 569         } else {
 570                 ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
 571                 /*
 572                  * Perform implict vfs_fsync_range() for fd_do_writev() ops
 573                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 574                  * Allow this to happen independent of WCE=0 setting.
 575                  */
 576                 if (ret > 0 &&
 577                     dev->dev_attrib.emulate_fua_write > 0 &&
 578                     (cmd->se_cmd_flags & SCF_FUA)) {
 579                         struct fd_dev *fd_dev = FD_DEV(dev);
 580                         loff_t start = cmd->t_task_lba *
 581                                 dev->dev_attrib.block_size;
 582                         loff_t end = start + cmd->data_length;
 583
 584                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 585                 }
 586         }
 587
 588         if (ret < 0)
 589                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 590
 591         if (ret)
 592                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 593         return 0;
 594 }
 595
 596 enum {
 597         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 598 };
 599
 600 static match_table_t tokens = {
 601         {Opt_fd_dev_name, "fd_dev_name=%s"},
 602         {Opt_fd_dev_size, "fd_dev_size=%s"},
 603         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 604         {Opt_err, NULL}
 605 };
 606
 607 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 608                 const char *page, ssize_t count)
 609 {
 610         struct fd_dev *fd_dev = FD_DEV(dev);
 611         char *orig, *ptr, *arg_p, *opts;
 612         substring_t args[MAX_OPT_ARGS];
 613         int ret = 0, arg, token;
 614
 615         opts = kstrdup(page, GFP_KERNEL);
 616         if (!opts)
 617                 return -ENOMEM;
 618
 619         orig = opts;
 620
 621         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 622                 if (!*ptr)
 623                         continue;
 624
 625                 token = match_token(ptr, tokens, args);
 626                 switch (token) {
 627                 case Opt_fd_dev_name:
 628                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 629                                 FD_MAX_DEV_NAME) == 0) {
 630                                 ret = -EINVAL;
 631                                 break;
 632                         }
 633                         pr_debug("FILEIO: Referencing Path: %s\n",
 634                                         fd_dev->fd_dev_name);
 635                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 636                         break;
 637                 case Opt_fd_dev_size:
 638                         arg_p = match_strdup(&args[0]);
 639                         if (!arg_p) {
 640                                 ret = -ENOMEM;
 641                                 break;
 642                         }
 643                         ret = strict_strtoull(arg_p, 0, &fd_dev->fd_dev_size);
 644                         kfree(arg_p);
 645                         if (ret < 0) {
 646                                 pr_err("strict_strtoull() failed for"
 647                                                 " fd_dev_size=\n");
 648                                 goto out;
 649                         }
 650                         pr_debug("FILEIO: Referencing Size: %llu"
 651                                         " bytes\n", fd_dev->fd_dev_size);
 652                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 653                         break;
 654                 case Opt_fd_buffered_io:
 655                         match_int(args, &arg);
 656                         if (arg != 1) {
 657                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 658                                 ret = -EINVAL;
 659                                 goto out;
 660                         }
 661
 662                         pr_debug("FILEIO: Using buffered I/O"
 663                                 " operations for struct fd_dev\n");
 664
 665                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 666                         break;
 667                 default:
 668                         break;
 669                 }
 670         }
 671
 672 out:
 673         kfree(orig);
 674         return (!ret) ? count : ret;
 675 }
 676
 677 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 678 {
 679         struct fd_dev *fd_dev = FD_DEV(dev);
 680         ssize_t bl = 0;
 681
 682         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 683         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 684                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 685                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 686                 "Buffered-WCE" : "O_DSYNC");
 687         return bl;
 688 }
 689
 690 static sector_t fd_get_blocks(struct se_device *dev)
 691 {
 692         struct fd_dev *fd_dev = FD_DEV(dev);
 693         struct file *f = fd_dev->fd_file;
 694         struct inode *i = f->f_mapping->host;
 695         unsigned long long dev_size;
 696         /*
 697          * When using a file that references an underlying struct block_device,
 698          * ensure dev_size is always based on the current inode size in order
 699          * to handle underlying block_device resize operations.
 700          */
 701         if (S_ISBLK(i->i_mode))
 702                 dev_size = (i_size_read(i) - fd_dev->fd_block_size);
 703         else
 704                 dev_size = fd_dev->fd_dev_size;
 705
 706         return div_u64(dev_size, dev->dev_attrib.block_size);
 707 }
 708
 709 static struct sbc_ops fd_sbc_ops = {
 710         .execute_rw             = fd_execute_rw,
 711         .execute_sync_cache     = fd_execute_sync_cache,
 712         .execute_write_same     = fd_execute_write_same,
 713         .execute_write_same_unmap = fd_execute_write_same_unmap,
 714         .execute_unmap          = fd_execute_unmap,
 715 };
 716
 717 static sense_reason_t
 718 fd_parse_cdb(struct se_cmd *cmd)
 719 {
 720         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 721 }
 722
 723 static struct se_subsystem_api fileio_template = {
 724         .name                   = "fileio",
 725         .inquiry_prod           = "FILEIO",
 726         .inquiry_rev            = FD_VERSION,
 727         .owner                  = THIS_MODULE,
 728         .transport_type         = TRANSPORT_PLUGIN_VHBA_PDEV,
 729         .attach_hba             = fd_attach_hba,
 730         .detach_hba             = fd_detach_hba,
 731         .alloc_device           = fd_alloc_device,
 732         .configure_device       = fd_configure_device,
 733         .free_device            = fd_free_device,
 734         .parse_cdb              = fd_parse_cdb,
 735         .set_configfs_dev_params = fd_set_configfs_dev_params,
 736         .show_configfs_dev_params = fd_show_configfs_dev_params,
 737         .get_device_type        = sbc_get_device_type,
 738         .get_blocks             = fd_get_blocks,
 739 };
 740
 741 static int __init fileio_module_init(void)
 742 {
 743         return transport_subsystem_register(&fileio_template);
 744 }
 745
 746 static void __exit fileio_module_exit(void)
 747 {
 748         transport_subsystem_release(&fileio_template);
 749 }
 750
 751 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
 752 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 753 MODULE_LICENSE("GPL");
 754
 755 module_init(fileio_module_init);
 756 module_exit(fileio_module_exit);