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 /*      fd_attach_hba(): (Part of se_subsystem_api_t template)
  50  *
  51  *
  52  */
  53 static int fd_attach_hba(struct se_hba *hba, u32 host_id)
  54 {
  55         struct fd_host *fd_host;
  56
  57         fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
  58         if (!fd_host) {
  59                 pr_err("Unable to allocate memory for struct fd_host\n");
  60                 return -ENOMEM;
  61         }
  62
  63         fd_host->fd_host_id = host_id;
  64
  65         hba->hba_ptr = fd_host;
  66
  67         pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
  68                 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
  69                 TARGET_CORE_MOD_VERSION);
  70         pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
  71                 hba->hba_id, fd_host->fd_host_id);
  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                 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
 157                 /*
 158                  * Determine the number of bytes from i_size_read() minus
 159                  * one (1) logical sector from underlying struct block_device
 160                  */
 161                 dev_size = (i_size_read(file->f_mapping->host) -
 162                                        fd_dev->fd_block_size);
 163
 164                 pr_debug("FILEIO: Using size: %llu bytes from struct"
 165                         " block_device blocks: %llu logical_block_size: %d\n",
 166                         dev_size, div_u64(dev_size, fd_dev->fd_block_size),
 167                         fd_dev->fd_block_size);
 168                 /*
 169                  * Check if the underlying struct block_device request_queue supports
 170                  * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
 171                  * in ATA and we need to set TPE=1
 172                  */
 173                 if (blk_queue_discard(q)) {
 174                         dev->dev_attrib.max_unmap_lba_count =
 175                                 q->limits.max_discard_sectors;
 176                         /*
 177                          * Currently hardcoded to 1 in Linux/SCSI code..
 178                          */
 179                         dev->dev_attrib.max_unmap_block_desc_count = 1;
 180                         dev->dev_attrib.unmap_granularity =
 181                                 q->limits.discard_granularity >> 9;
 182                         dev->dev_attrib.unmap_granularity_alignment =
 183                                 q->limits.discard_alignment;
 184                         pr_debug("IFILE: BLOCK Discard support available,"
 185                                         " disabled by default\n");
 186                 }
 187                 /*
 188                  * Enable write same emulation for IBLOCK and use 0xFFFF as
 189                  * the smaller WRITE_SAME(10) only has a two-byte block count.
 190                  */
 191                 dev->dev_attrib.max_write_same_len = 0xFFFF;
 192
 193                 if (blk_queue_nonrot(q))
 194                         dev->dev_attrib.is_nonrot = 1;
 195         } else {
 196                 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
 197                         pr_err("FILEIO: Missing fd_dev_size="
 198                                 " parameter, and no backing struct"
 199                                 " block_device\n");
 200                         goto fail;
 201                 }
 202
 203                 fd_dev->fd_block_size = FD_BLOCKSIZE;
 204                 /*
 205                  * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
 206                  */
 207                 dev->dev_attrib.max_unmap_lba_count = 0x2000;
 208                 /*
 209                  * Currently hardcoded to 1 in Linux/SCSI code..
 210                  */
 211                 dev->dev_attrib.max_unmap_block_desc_count = 1;
 212                 dev->dev_attrib.unmap_granularity = 1;
 213                 dev->dev_attrib.unmap_granularity_alignment = 0;
 214
 215                 /*
 216                  * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
 217                  * based upon struct iovec limit for vfs_writev()
 218                  */
 219                 dev->dev_attrib.max_write_same_len = 0x1000;
 220         }
 221
 222         dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
 223         dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES;
 224         dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
 225         dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
 226
 227         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
 228                 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
 229                         " with FDBD_HAS_BUFFERED_IO_WCE\n");
 230                 dev->dev_attrib.emulate_write_cache = 1;
 231         }
 232
 233         fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
 234         fd_dev->fd_queue_depth = dev->queue_depth;
 235
 236         pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
 237                 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
 238                         fd_dev->fd_dev_name, fd_dev->fd_dev_size);
 239
 240         return 0;
 241 fail:
 242         if (fd_dev->fd_file) {
 243                 filp_close(fd_dev->fd_file, NULL);
 244                 fd_dev->fd_file = NULL;
 245         }
 246         return ret;
 247 }
 248
 249 static void fd_free_device(struct se_device *dev)
 250 {
 251         struct fd_dev *fd_dev = FD_DEV(dev);
 252
 253         if (fd_dev->fd_file) {
 254                 filp_close(fd_dev->fd_file, NULL);
 255                 fd_dev->fd_file = NULL;
 256         }
 257
 258         kfree(fd_dev);
 259 }
 260
 261 static int fd_do_rw(struct se_cmd *cmd, struct file *fd,
 262                     u32 block_size, struct scatterlist *sgl,
 263                     u32 sgl_nents, u32 data_length, int is_write)
 264 {
 265         struct scatterlist *sg;
 266         struct iov_iter iter;
 267         struct bio_vec *bvec;
 268         ssize_t len = 0;
 269         loff_t pos = (cmd->t_task_lba * block_size);
 270         int ret = 0, i;
 271
 272         bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
 273         if (!bvec) {
 274                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 275                 return -ENOMEM;
 276         }
 277
 278         for_each_sg(sgl, sg, sgl_nents, i) {
 279                 bvec[i].bv_page = sg_page(sg);
 280                 bvec[i].bv_len = sg->length;
 281                 bvec[i].bv_offset = sg->offset;
 282
 283                 len += sg->length;
 284         }
 285
 286         iov_iter_bvec(&iter, ITER_BVEC, bvec, sgl_nents, len);
 287         if (is_write)
 288                 ret = vfs_iter_write(fd, &iter, &pos);
 289         else
 290                 ret = vfs_iter_read(fd, &iter, &pos);
 291
 292         kfree(bvec);
 293
 294         if (is_write) {
 295                 if (ret < 0 || ret != data_length) {
 296                         pr_err("%s() write returned %d\n", __func__, ret);
 297                         return (ret < 0 ? ret : -EINVAL);
 298                 }
 299         } else {
 300                 /*
 301                  * Return zeros and GOOD status even if the READ did not return
 302                  * the expected virt_size for struct file w/o a backing struct
 303                  * block_device.
 304                  */
 305                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 306                         if (ret < 0 || ret != data_length) {
 307                                 pr_err("%s() returned %d, expecting %u for "
 308                                                 "S_ISBLK\n", __func__, ret,
 309                                                 data_length);
 310                                 return (ret < 0 ? ret : -EINVAL);
 311                         }
 312                 } else {
 313                         if (ret < 0) {
 314                                 pr_err("%s() returned %d for non S_ISBLK\n",
 315                                                 __func__, ret);
 316                                 return ret;
 317                         }
 318                 }
 319         }
 320         return 1;
 321 }
 322
 323 static sense_reason_t
 324 fd_execute_sync_cache(struct se_cmd *cmd)
 325 {
 326         struct se_device *dev = cmd->se_dev;
 327         struct fd_dev *fd_dev = FD_DEV(dev);
 328         int immed = (cmd->t_task_cdb[1] & 0x2);
 329         loff_t start, end;
 330         int ret;
 331
 332         /*
 333          * If the Immediate bit is set, queue up the GOOD response
 334          * for this SYNCHRONIZE_CACHE op
 335          */
 336         if (immed)
 337                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 338
 339         /*
 340          * Determine if we will be flushing the entire device.
 341          */
 342         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 343                 start = 0;
 344                 end = LLONG_MAX;
 345         } else {
 346                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 347                 if (cmd->data_length)
 348                         end = start + cmd->data_length - 1;
 349                 else
 350                         end = LLONG_MAX;
 351         }
 352
 353         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 354         if (ret != 0)
 355                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 356
 357         if (immed)
 358                 return 0;
 359
 360         if (ret)
 361                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 362         else
 363                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 364
 365         return 0;
 366 }
 367
 368 static sense_reason_t
 369 fd_execute_write_same(struct se_cmd *cmd)
 370 {
 371         struct se_device *se_dev = cmd->se_dev;
 372         struct fd_dev *fd_dev = FD_DEV(se_dev);
 373         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 374         sector_t nolb = sbc_get_write_same_sectors(cmd);
 375         struct iov_iter iter;
 376         struct bio_vec *bvec;
 377         unsigned int len = 0, i;
 378         ssize_t ret;
 379
 380         if (!nolb) {
 381                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 382                 return 0;
 383         }
 384         if (cmd->prot_op) {
 385                 pr_err("WRITE_SAME: Protection information with FILEIO"
 386                        " backends not supported\n");
 387                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 388         }
 389
 390         if (cmd->t_data_nents > 1 ||
 391             cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
 392                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 393                         " block_size: %u\n",
 394                         cmd->t_data_nents,
 395                         cmd->t_data_sg[0].length,
 396                         cmd->se_dev->dev_attrib.block_size);
 397                 return TCM_INVALID_CDB_FIELD;
 398         }
 399
 400         bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
 401         if (!bvec)
 402                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 403
 404         for (i = 0; i < nolb; i++) {
 405                 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
 406                 bvec[i].bv_len = cmd->t_data_sg[0].length;
 407                 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
 408
 409                 len += se_dev->dev_attrib.block_size;
 410         }
 411
 412         iov_iter_bvec(&iter, ITER_BVEC, bvec, nolb, len);
 413         ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos);
 414
 415         kfree(bvec);
 416         if (ret < 0 || ret != len) {
 417                 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
 418                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 419         }
 420
 421         target_complete_cmd(cmd, SAM_STAT_GOOD);
 422         return 0;
 423 }
 424
 425 static int
 426 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
 427                 void *buf, size_t bufsize)
 428 {
 429         struct fd_dev *fd_dev = FD_DEV(se_dev);
 430         struct file *prot_fd = fd_dev->fd_prot_file;
 431         sector_t prot_length, prot;
 432         loff_t pos = lba * se_dev->prot_length;
 433
 434         if (!prot_fd) {
 435                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 436                 return -ENODEV;
 437         }
 438
 439         prot_length = nolb * se_dev->prot_length;
 440
 441         for (prot = 0; prot < prot_length;) {
 442                 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
 443                 ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
 444
 445                 if (ret != len) {
 446                         pr_err("vfs_write to prot file failed: %zd\n", ret);
 447                         return ret < 0 ? ret : -ENODEV;
 448                 }
 449                 prot += ret;
 450         }
 451
 452         return 0;
 453 }
 454
 455 static int
 456 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
 457 {
 458         void *buf;
 459         int rc;
 460
 461         buf = (void *)__get_free_page(GFP_KERNEL);
 462         if (!buf) {
 463                 pr_err("Unable to allocate FILEIO prot buf\n");
 464                 return -ENOMEM;
 465         }
 466         memset(buf, 0xff, PAGE_SIZE);
 467
 468         rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
 469
 470         free_page((unsigned long)buf);
 471
 472         return rc;
 473 }
 474
 475 static sense_reason_t
 476 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 477 {
 478         struct file *file = priv;
 479         struct inode *inode = file->f_mapping->host;
 480         int ret;
 481
 482         if (cmd->se_dev->dev_attrib.pi_prot_type) {
 483                 ret = fd_do_prot_unmap(cmd, lba, nolb);
 484                 if (ret)
 485                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 486         }
 487
 488         if (S_ISBLK(inode->i_mode)) {
 489                 /* The backend is block device, use discard */
 490                 struct block_device *bdev = inode->i_bdev;
 491
 492                 ret = blkdev_issue_discard(bdev, lba,
 493                                 nolb, GFP_KERNEL, 0);
 494                 if (ret < 0) {
 495                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 496                                 ret);
 497                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 498                 }
 499         } else {
 500                 /* The backend is normal file, use fallocate */
 501                 struct se_device *se_dev = cmd->se_dev;
 502                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 503                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 504                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 505
 506                 if (!file->f_op->fallocate)
 507                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 508
 509                 ret = file->f_op->fallocate(file, mode, pos, len);
 510                 if (ret < 0) {
 511                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 512                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 513                 }
 514         }
 515
 516         return 0;
 517 }
 518
 519 static sense_reason_t
 520 fd_execute_write_same_unmap(struct se_cmd *cmd)
 521 {
 522         struct se_device *se_dev = cmd->se_dev;
 523         struct fd_dev *fd_dev = FD_DEV(se_dev);
 524         struct file *file = fd_dev->fd_file;
 525         sector_t lba = cmd->t_task_lba;
 526         sector_t nolb = sbc_get_write_same_sectors(cmd);
 527         sense_reason_t ret;
 528
 529         if (!nolb) {
 530                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 531                 return 0;
 532         }
 533
 534         ret = fd_do_unmap(cmd, file, lba, nolb);
 535         if (ret)
 536                 return ret;
 537
 538         target_complete_cmd(cmd, GOOD);
 539         return 0;
 540 }
 541
 542 static sense_reason_t
 543 fd_execute_unmap(struct se_cmd *cmd)
 544 {
 545         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 546
 547         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 548 }
 549
 550 static sense_reason_t
 551 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 552               enum dma_data_direction data_direction)
 553 {
 554         struct se_device *dev = cmd->se_dev;
 555         struct fd_dev *fd_dev = FD_DEV(dev);
 556         struct file *file = fd_dev->fd_file;
 557         struct file *pfile = fd_dev->fd_prot_file;
 558         sense_reason_t rc;
 559         int ret = 0;
 560         /*
 561          * We are currently limited by the number of iovecs (2048) per
 562          * single vfs_[writev,readv] call.
 563          */
 564         if (cmd->data_length > FD_MAX_BYTES) {
 565                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 566                        "FD_MAX_BYTES: %u iovec count limitiation\n",
 567                         cmd->data_length, FD_MAX_BYTES);
 568                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 569         }
 570         /*
 571          * Call vectorized fileio functions to map struct scatterlist
 572          * physical memory addresses to struct iovec virtual memory.
 573          */
 574         if (data_direction == DMA_FROM_DEVICE) {
 575                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 576                         ret = fd_do_rw(cmd, pfile, dev->prot_length,
 577                                        cmd->t_prot_sg, cmd->t_prot_nents,
 578                                        cmd->prot_length, 0);
 579                         if (ret < 0)
 580                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 581                 }
 582
 583                 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
 584                                sgl, sgl_nents, cmd->data_length, 0);
 585
 586                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 587                         u32 sectors = cmd->data_length >>
 588                                         ilog2(dev->dev_attrib.block_size);
 589
 590                         rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
 591                                             0, cmd->t_prot_sg, 0);
 592                         if (rc)
 593                                 return rc;
 594                 }
 595         } else {
 596                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 597                         u32 sectors = cmd->data_length >>
 598                                         ilog2(dev->dev_attrib.block_size);
 599
 600                         rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors,
 601                                             0, cmd->t_prot_sg, 0);
 602                         if (rc)
 603                                 return rc;
 604                 }
 605
 606                 ret = fd_do_rw(cmd, file, dev->dev_attrib.block_size,
 607                                sgl, sgl_nents, cmd->data_length, 1);
 608                 /*
 609                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 610                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 611                  * Allow this to happen independent of WCE=0 setting.
 612                  */
 613                 if (ret > 0 && (cmd->se_cmd_flags & SCF_FUA)) {
 614                         loff_t start = cmd->t_task_lba *
 615                                 dev->dev_attrib.block_size;
 616                         loff_t end;
 617
 618                         if (cmd->data_length)
 619                                 end = start + cmd->data_length - 1;
 620                         else
 621                                 end = LLONG_MAX;
 622
 623                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 624                 }
 625
 626                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 627                         ret = fd_do_rw(cmd, pfile, dev->prot_length,
 628                                        cmd->t_prot_sg, cmd->t_prot_nents,
 629                                        cmd->prot_length, 1);
 630                         if (ret < 0)
 631                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 632                 }
 633         }
 634
 635         if (ret < 0)
 636                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 637
 638         if (ret)
 639                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 640         return 0;
 641 }
 642
 643 enum {
 644         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 645 };
 646
 647 static match_table_t tokens = {
 648         {Opt_fd_dev_name, "fd_dev_name=%s"},
 649         {Opt_fd_dev_size, "fd_dev_size=%s"},
 650         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 651         {Opt_err, NULL}
 652 };
 653
 654 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 655                 const char *page, ssize_t count)
 656 {
 657         struct fd_dev *fd_dev = FD_DEV(dev);
 658         char *orig, *ptr, *arg_p, *opts;
 659         substring_t args[MAX_OPT_ARGS];
 660         int ret = 0, arg, token;
 661
 662         opts = kstrdup(page, GFP_KERNEL);
 663         if (!opts)
 664                 return -ENOMEM;
 665
 666         orig = opts;
 667
 668         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 669                 if (!*ptr)
 670                         continue;
 671
 672                 token = match_token(ptr, tokens, args);
 673                 switch (token) {
 674                 case Opt_fd_dev_name:
 675                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 676                                 FD_MAX_DEV_NAME) == 0) {
 677                                 ret = -EINVAL;
 678                                 break;
 679                         }
 680                         pr_debug("FILEIO: Referencing Path: %s\n",
 681                                         fd_dev->fd_dev_name);
 682                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 683                         break;
 684                 case Opt_fd_dev_size:
 685                         arg_p = match_strdup(&args[0]);
 686                         if (!arg_p) {
 687                                 ret = -ENOMEM;
 688                                 break;
 689                         }
 690                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 691                         kfree(arg_p);
 692                         if (ret < 0) {
 693                                 pr_err("kstrtoull() failed for"
 694                                                 " fd_dev_size=\n");
 695                                 goto out;
 696                         }
 697                         pr_debug("FILEIO: Referencing Size: %llu"
 698                                         " bytes\n", fd_dev->fd_dev_size);
 699                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 700                         break;
 701                 case Opt_fd_buffered_io:
 702                         ret = match_int(args, &arg);
 703                         if (ret)
 704                                 goto out;
 705                         if (arg != 1) {
 706                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 707                                 ret = -EINVAL;
 708                                 goto out;
 709                         }
 710
 711                         pr_debug("FILEIO: Using buffered I/O"
 712                                 " operations for struct fd_dev\n");
 713
 714                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 715                         break;
 716                 default:
 717                         break;
 718                 }
 719         }
 720
 721 out:
 722         kfree(orig);
 723         return (!ret) ? count : ret;
 724 }
 725
 726 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 727 {
 728         struct fd_dev *fd_dev = FD_DEV(dev);
 729         ssize_t bl = 0;
 730
 731         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 732         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 733                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 734                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 735                 "Buffered-WCE" : "O_DSYNC");
 736         return bl;
 737 }
 738
 739 static sector_t fd_get_blocks(struct se_device *dev)
 740 {
 741         struct fd_dev *fd_dev = FD_DEV(dev);
 742         struct file *f = fd_dev->fd_file;
 743         struct inode *i = f->f_mapping->host;
 744         unsigned long long dev_size;
 745         /*
 746          * When using a file that references an underlying struct block_device,
 747          * ensure dev_size is always based on the current inode size in order
 748          * to handle underlying block_device resize operations.
 749          */
 750         if (S_ISBLK(i->i_mode))
 751                 dev_size = i_size_read(i);
 752         else
 753                 dev_size = fd_dev->fd_dev_size;
 754
 755         return div_u64(dev_size - dev->dev_attrib.block_size,
 756                        dev->dev_attrib.block_size);
 757 }
 758
 759 static int fd_init_prot(struct se_device *dev)
 760 {
 761         struct fd_dev *fd_dev = FD_DEV(dev);
 762         struct file *prot_file, *file = fd_dev->fd_file;
 763         struct inode *inode;
 764         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 765         char buf[FD_MAX_DEV_PROT_NAME];
 766
 767         if (!file) {
 768                 pr_err("Unable to locate fd_dev->fd_file\n");
 769                 return -ENODEV;
 770         }
 771
 772         inode = file->f_mapping->host;
 773         if (S_ISBLK(inode->i_mode)) {
 774                 pr_err("FILEIO Protection emulation only supported on"
 775                        " !S_ISBLK\n");
 776                 return -ENOSYS;
 777         }
 778
 779         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 780                 flags &= ~O_DSYNC;
 781
 782         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 783                  fd_dev->fd_dev_name);
 784
 785         prot_file = filp_open(buf, flags, 0600);
 786         if (IS_ERR(prot_file)) {
 787                 pr_err("filp_open(%s) failed\n", buf);
 788                 ret = PTR_ERR(prot_file);
 789                 return ret;
 790         }
 791         fd_dev->fd_prot_file = prot_file;
 792
 793         return 0;
 794 }
 795
 796 static int fd_format_prot(struct se_device *dev)
 797 {
 798         unsigned char *buf;
 799         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 800         int ret;
 801
 802         if (!dev->dev_attrib.pi_prot_type) {
 803                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 804                 return -ENODEV;
 805         }
 806
 807         buf = vzalloc(unit_size);
 808         if (!buf) {
 809                 pr_err("Unable to allocate FILEIO prot buf\n");
 810                 return -ENOMEM;
 811         }
 812
 813         pr_debug("Using FILEIO prot_length: %llu\n",
 814                  (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
 815                                         dev->prot_length);
 816
 817         memset(buf, 0xff, unit_size);
 818         ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
 819                               buf, unit_size);
 820         vfree(buf);
 821         return ret;
 822 }
 823
 824 static void fd_free_prot(struct se_device *dev)
 825 {
 826         struct fd_dev *fd_dev = FD_DEV(dev);
 827
 828         if (!fd_dev->fd_prot_file)
 829                 return;
 830
 831         filp_close(fd_dev->fd_prot_file, NULL);
 832         fd_dev->fd_prot_file = NULL;
 833 }
 834
 835 static struct sbc_ops fd_sbc_ops = {
 836         .execute_rw             = fd_execute_rw,
 837         .execute_sync_cache     = fd_execute_sync_cache,
 838         .execute_write_same     = fd_execute_write_same,
 839         .execute_write_same_unmap = fd_execute_write_same_unmap,
 840         .execute_unmap          = fd_execute_unmap,
 841 };
 842
 843 static sense_reason_t
 844 fd_parse_cdb(struct se_cmd *cmd)
 845 {
 846         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 847 }
 848
 849 DEF_TB_DEFAULT_ATTRIBS(fileio);
 850
 851 static struct configfs_attribute *fileio_backend_dev_attrs[] = {
 852         &fileio_dev_attrib_emulate_model_alias.attr,
 853         &fileio_dev_attrib_emulate_dpo.attr,
 854         &fileio_dev_attrib_emulate_fua_write.attr,
 855         &fileio_dev_attrib_emulate_fua_read.attr,
 856         &fileio_dev_attrib_emulate_write_cache.attr,
 857         &fileio_dev_attrib_emulate_ua_intlck_ctrl.attr,
 858         &fileio_dev_attrib_emulate_tas.attr,
 859         &fileio_dev_attrib_emulate_tpu.attr,
 860         &fileio_dev_attrib_emulate_tpws.attr,
 861         &fileio_dev_attrib_emulate_caw.attr,
 862         &fileio_dev_attrib_emulate_3pc.attr,
 863         &fileio_dev_attrib_pi_prot_type.attr,
 864         &fileio_dev_attrib_hw_pi_prot_type.attr,
 865         &fileio_dev_attrib_pi_prot_format.attr,
 866         &fileio_dev_attrib_enforce_pr_isids.attr,
 867         &fileio_dev_attrib_is_nonrot.attr,
 868         &fileio_dev_attrib_emulate_rest_reord.attr,
 869         &fileio_dev_attrib_force_pr_aptpl.attr,
 870         &fileio_dev_attrib_hw_block_size.attr,
 871         &fileio_dev_attrib_block_size.attr,
 872         &fileio_dev_attrib_hw_max_sectors.attr,
 873         &fileio_dev_attrib_optimal_sectors.attr,
 874         &fileio_dev_attrib_hw_queue_depth.attr,
 875         &fileio_dev_attrib_queue_depth.attr,
 876         &fileio_dev_attrib_max_unmap_lba_count.attr,
 877         &fileio_dev_attrib_max_unmap_block_desc_count.attr,
 878         &fileio_dev_attrib_unmap_granularity.attr,
 879         &fileio_dev_attrib_unmap_granularity_alignment.attr,
 880         &fileio_dev_attrib_max_write_same_len.attr,
 881         NULL,
 882 };
 883
 884 static struct se_subsystem_api fileio_template = {
 885         .name                   = "fileio",
 886         .inquiry_prod           = "FILEIO",
 887         .inquiry_rev            = FD_VERSION,
 888         .owner                  = THIS_MODULE,
 889         .attach_hba             = fd_attach_hba,
 890         .detach_hba             = fd_detach_hba,
 891         .alloc_device           = fd_alloc_device,
 892         .configure_device       = fd_configure_device,
 893         .free_device            = fd_free_device,
 894         .parse_cdb              = fd_parse_cdb,
 895         .set_configfs_dev_params = fd_set_configfs_dev_params,
 896         .show_configfs_dev_params = fd_show_configfs_dev_params,
 897         .get_device_type        = sbc_get_device_type,
 898         .get_blocks             = fd_get_blocks,
 899         .init_prot              = fd_init_prot,
 900         .format_prot            = fd_format_prot,
 901         .free_prot              = fd_free_prot,
 902 };
 903
 904 static int __init fileio_module_init(void)
 905 {
 906         struct target_backend_cits *tbc = &fileio_template.tb_cits;
 907
 908         target_core_setup_sub_cits(&fileio_template);
 909         tbc->tb_dev_attrib_cit.ct_attrs = fileio_backend_dev_attrs;
 910
 911         return transport_subsystem_register(&fileio_template);
 912 }
 913
 914 static void __exit fileio_module_exit(void)
 915 {
 916         transport_subsystem_release(&fileio_template);
 917 }
 918
 919 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
 920 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 921 MODULE_LICENSE("GPL");
 922
 923 module_init(fileio_module_init);
 924 module_exit(fileio_module_exit);