drivers/target/target_core_file.c

   1 /*******************************************************************************
   2  * Filename:  target_core_file.c
   3  *
   4  * This file contains the Storage Engine <-> FILEIO transport specific functions
   5  *
   6  * (c) Copyright 2005-2013 Datera, Inc.
   7  *
   8  * Nicholas A. Bellinger <nab@kernel.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  ******************************************************************************/
  25
  26 #include <linux/string.h>
  27 #include <linux/parser.h>
  28 #include <linux/timer.h>
  29 #include <linux/blkdev.h>
  30 #include <linux/slab.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/module.h>
  33 #include <linux/vmalloc.h>
  34 #include <linux/falloc.h>
  35 #include <scsi/scsi.h>
  36 #include <scsi/scsi_host.h>
  37 #include <asm/unaligned.h>
  38
  39 #include <target/target_core_base.h>
  40 #include <target/target_core_backend.h>
  41 #include <target/target_core_backend_configfs.h>
  42
  43 #include "target_core_file.h"
  44
  45 static inline struct fd_dev *FD_DEV(struct se_device *dev)
  46 {
  47         return container_of(dev, struct fd_dev, dev);
  48 }
  49
  50 /*      fd_attach_hba(): (Part of se_subsystem_api_t template)
  51  *
  52  *
  53  */
  54 static int fd_attach_hba(struct se_hba *hba, u32 host_id)
  55 {
  56         struct fd_host *fd_host;
  57
  58         fd_host = kzalloc(sizeof(struct fd_host), GFP_KERNEL);
  59         if (!fd_host) {
  60                 pr_err("Unable to allocate memory for struct fd_host\n");
  61                 return -ENOMEM;
  62         }
  63
  64         fd_host->fd_host_id = host_id;
  65
  66         hba->hba_ptr = fd_host;
  67
  68         pr_debug("CORE_HBA[%d] - TCM FILEIO HBA Driver %s on Generic"
  69                 " Target Core Stack %s\n", hba->hba_id, FD_VERSION,
  70                 TARGET_CORE_MOD_VERSION);
  71         pr_debug("CORE_HBA[%d] - Attached FILEIO HBA: %u to Generic\n",
  72                 hba->hba_id, fd_host->fd_host_id);
  73
  74         return 0;
  75 }
  76
  77 static void fd_detach_hba(struct se_hba *hba)
  78 {
  79         struct fd_host *fd_host = hba->hba_ptr;
  80
  81         pr_debug("CORE_HBA[%d] - Detached FILEIO HBA: %u from Generic"
  82                 " Target Core\n", hba->hba_id, fd_host->fd_host_id);
  83
  84         kfree(fd_host);
  85         hba->hba_ptr = NULL;
  86 }
  87
  88 static struct se_device *fd_alloc_device(struct se_hba *hba, const char *name)
  89 {
  90         struct fd_dev *fd_dev;
  91         struct fd_host *fd_host = hba->hba_ptr;
  92
  93         fd_dev = kzalloc(sizeof(struct fd_dev), GFP_KERNEL);
  94         if (!fd_dev) {
  95                 pr_err("Unable to allocate memory for struct fd_dev\n");
  96                 return NULL;
  97         }
  98
  99         fd_dev->fd_host = fd_host;
 100
 101         pr_debug("FILEIO: Allocated fd_dev for %p\n", name);
 102
 103         return &fd_dev->dev;
 104 }
 105
 106 static int fd_configure_device(struct se_device *dev)
 107 {
 108         struct fd_dev *fd_dev = FD_DEV(dev);
 109         struct fd_host *fd_host = dev->se_hba->hba_ptr;
 110         struct file *file;
 111         struct inode *inode = NULL;
 112         int flags, ret = -EINVAL;
 113
 114         if (!(fd_dev->fbd_flags & FBDF_HAS_PATH)) {
 115                 pr_err("Missing fd_dev_name=\n");
 116                 return -EINVAL;
 117         }
 118
 119         /*
 120          * Use O_DSYNC by default instead of O_SYNC to forgo syncing
 121          * of pure timestamp updates.
 122          */
 123         flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 124
 125         /*
 126          * Optionally allow fd_buffered_io=1 to be enabled for people
 127          * who want use the fs buffer cache as an WriteCache mechanism.
 128          *
 129          * This means that in event of a hard failure, there is a risk
 130          * of silent data-loss if the SCSI client has *not* performed a
 131          * forced unit access (FUA) write, or issued SYNCHRONIZE_CACHE
 132          * to write-out the entire device cache.
 133          */
 134         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
 135                 pr_debug("FILEIO: Disabling O_DSYNC, using buffered FILEIO\n");
 136                 flags &= ~O_DSYNC;
 137         }
 138
 139         file = filp_open(fd_dev->fd_dev_name, flags, 0600);
 140         if (IS_ERR(file)) {
 141                 pr_err("filp_open(%s) failed\n", fd_dev->fd_dev_name);
 142                 ret = PTR_ERR(file);
 143                 goto fail;
 144         }
 145         fd_dev->fd_file = file;
 146         /*
 147          * If using a block backend with this struct file, we extract
 148          * fd_dev->fd_[block,dev]_size from struct block_device.
 149          *
 150          * Otherwise, we use the passed fd_size= from configfs
 151          */
 152         inode = file->f_mapping->host;
 153         if (S_ISBLK(inode->i_mode)) {
 154                 struct request_queue *q = bdev_get_queue(inode->i_bdev);
 155                 unsigned long long dev_size;
 156
 157                 fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
 158                 /*
 159                  * Determine the number of bytes from i_size_read() minus
 160                  * one (1) logical sector from underlying struct block_device
 161                  */
 162                 dev_size = (i_size_read(file->f_mapping->host) -
 163                                        fd_dev->fd_block_size);
 164
 165                 pr_debug("FILEIO: Using size: %llu bytes from struct"
 166                         " block_device blocks: %llu logical_block_size: %d\n",
 167                         dev_size, div_u64(dev_size, fd_dev->fd_block_size),
 168                         fd_dev->fd_block_size);
 169                 /*
 170                  * Check if the underlying struct block_device request_queue supports
 171                  * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
 172                  * in ATA and we need to set TPE=1
 173                  */
 174                 if (blk_queue_discard(q)) {
 175                         dev->dev_attrib.max_unmap_lba_count =
 176                                 q->limits.max_discard_sectors;
 177                         /*
 178                          * Currently hardcoded to 1 in Linux/SCSI code..
 179                          */
 180                         dev->dev_attrib.max_unmap_block_desc_count = 1;
 181                         dev->dev_attrib.unmap_granularity =
 182                                 q->limits.discard_granularity >> 9;
 183                         dev->dev_attrib.unmap_granularity_alignment =
 184                                 q->limits.discard_alignment;
 185                         pr_debug("IFILE: BLOCK Discard support available,"
 186                                         " disabled by default\n");
 187                 }
 188                 /*
 189                  * Enable write same emulation for IBLOCK and use 0xFFFF as
 190                  * the smaller WRITE_SAME(10) only has a two-byte block count.
 191                  */
 192                 dev->dev_attrib.max_write_same_len = 0xFFFF;
 193
 194                 if (blk_queue_nonrot(q))
 195                         dev->dev_attrib.is_nonrot = 1;
 196         } else {
 197                 if (!(fd_dev->fbd_flags & FBDF_HAS_SIZE)) {
 198                         pr_err("FILEIO: Missing fd_dev_size="
 199                                 " parameter, and no backing struct"
 200                                 " block_device\n");
 201                         goto fail;
 202                 }
 203
 204                 fd_dev->fd_block_size = FD_BLOCKSIZE;
 205                 /*
 206                  * Limit UNMAP emulation to 8k Number of LBAs (NoLB)
 207                  */
 208                 dev->dev_attrib.max_unmap_lba_count = 0x2000;
 209                 /*
 210                  * Currently hardcoded to 1 in Linux/SCSI code..
 211                  */
 212                 dev->dev_attrib.max_unmap_block_desc_count = 1;
 213                 dev->dev_attrib.unmap_granularity = 1;
 214                 dev->dev_attrib.unmap_granularity_alignment = 0;
 215
 216                 /*
 217                  * Limit WRITE_SAME w/ UNMAP=0 emulation to 8k Number of LBAs (NoLB)
 218                  * based upon struct iovec limit for vfs_writev()
 219                  */
 220                 dev->dev_attrib.max_write_same_len = 0x1000;
 221         }
 222
 223         dev->dev_attrib.hw_block_size = fd_dev->fd_block_size;
 224         dev->dev_attrib.max_bytes_per_io = FD_MAX_BYTES;
 225         dev->dev_attrib.hw_max_sectors = FD_MAX_BYTES / fd_dev->fd_block_size;
 226         dev->dev_attrib.hw_queue_depth = FD_MAX_DEVICE_QUEUE_DEPTH;
 227
 228         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) {
 229                 pr_debug("FILEIO: Forcing setting of emulate_write_cache=1"
 230                         " with FDBD_HAS_BUFFERED_IO_WCE\n");
 231                 dev->dev_attrib.emulate_write_cache = 1;
 232         }
 233
 234         fd_dev->fd_dev_id = fd_host->fd_host_dev_id_count++;
 235         fd_dev->fd_queue_depth = dev->queue_depth;
 236
 237         pr_debug("CORE_FILE[%u] - Added TCM FILEIO Device ID: %u at %s,"
 238                 " %llu total bytes\n", fd_host->fd_host_id, fd_dev->fd_dev_id,
 239                         fd_dev->fd_dev_name, fd_dev->fd_dev_size);
 240
 241         return 0;
 242 fail:
 243         if (fd_dev->fd_file) {
 244                 filp_close(fd_dev->fd_file, NULL);
 245                 fd_dev->fd_file = NULL;
 246         }
 247         return ret;
 248 }
 249
 250 static void fd_free_device(struct se_device *dev)
 251 {
 252         struct fd_dev *fd_dev = FD_DEV(dev);
 253
 254         if (fd_dev->fd_file) {
 255                 filp_close(fd_dev->fd_file, NULL);
 256                 fd_dev->fd_file = NULL;
 257         }
 258
 259         kfree(fd_dev);
 260 }
 261
 262 static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
 263                          int is_write)
 264 {
 265         struct se_device *se_dev = cmd->se_dev;
 266         struct fd_dev *dev = FD_DEV(se_dev);
 267         struct file *prot_fd = dev->fd_prot_file;
 268         loff_t pos = (cmd->t_task_lba * se_dev->prot_length);
 269         unsigned char *buf;
 270         u32 prot_size;
 271         int rc, ret = 1;
 272
 273         prot_size = (cmd->data_length / se_dev->dev_attrib.block_size) *
 274                      se_dev->prot_length;
 275
 276         if (!is_write) {
 277                 fd_prot->prot_buf = kzalloc(prot_size, GFP_KERNEL);
 278                 if (!fd_prot->prot_buf) {
 279                         pr_err("Unable to allocate fd_prot->prot_buf\n");
 280                         return -ENOMEM;
 281                 }
 282                 buf = fd_prot->prot_buf;
 283
 284                 fd_prot->prot_sg_nents = 1;
 285                 fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist),
 286                                            GFP_KERNEL);
 287                 if (!fd_prot->prot_sg) {
 288                         pr_err("Unable to allocate fd_prot->prot_sg\n");
 289                         kfree(fd_prot->prot_buf);
 290                         return -ENOMEM;
 291                 }
 292                 sg_init_table(fd_prot->prot_sg, fd_prot->prot_sg_nents);
 293                 sg_set_buf(fd_prot->prot_sg, buf, prot_size);
 294         }
 295
 296         if (is_write) {
 297                 rc = kernel_write(prot_fd, fd_prot->prot_buf, prot_size, pos);
 298                 if (rc < 0 || prot_size != rc) {
 299                         pr_err("kernel_write() for fd_do_prot_rw failed:"
 300                                " %d\n", rc);
 301                         ret = -EINVAL;
 302                 }
 303         } else {
 304                 rc = kernel_read(prot_fd, pos, fd_prot->prot_buf, prot_size);
 305                 if (rc < 0) {
 306                         pr_err("kernel_read() for fd_do_prot_rw failed:"
 307                                " %d\n", rc);
 308                         ret = -EINVAL;
 309                 }
 310         }
 311
 312         if (is_write || ret < 0) {
 313                 kfree(fd_prot->prot_sg);
 314                 kfree(fd_prot->prot_buf);
 315         }
 316
 317         return ret;
 318 }
 319
 320 static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
 321                 u32 sgl_nents, int is_write)
 322 {
 323         struct se_device *se_dev = cmd->se_dev;
 324         struct fd_dev *dev = FD_DEV(se_dev);
 325         struct file *fd = dev->fd_file;
 326         struct scatterlist *sg;
 327         struct iov_iter iter;
 328         struct bio_vec *bvec;
 329         ssize_t len = 0;
 330         loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
 331         int ret = 0, i;
 332
 333         bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
 334         if (!bvec) {
 335                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 336                 return -ENOMEM;
 337         }
 338
 339         for_each_sg(sgl, sg, sgl_nents, i) {
 340                 bvec[i].bv_page = sg_page(sg);
 341                 bvec[i].bv_len = sg->length;
 342                 bvec[i].bv_offset = sg->offset;
 343
 344                 len += sg->length;
 345         }
 346
 347         iov_iter_bvec(&iter, ITER_BVEC, bvec, sgl_nents, len);
 348         if (is_write)
 349                 ret = vfs_iter_write(fd, &iter, &pos);
 350         else
 351                 ret = vfs_iter_read(fd, &iter, &pos);
 352
 353         kfree(bvec);
 354
 355         if (is_write) {
 356                 if (ret < 0 || ret != cmd->data_length) {
 357                         pr_err("%s() write returned %d\n", __func__, ret);
 358                         return (ret < 0 ? ret : -EINVAL);
 359                 }
 360         } else {
 361                 /*
 362                  * Return zeros and GOOD status even if the READ did not return
 363                  * the expected virt_size for struct file w/o a backing struct
 364                  * block_device.
 365                  */
 366                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 367                         if (ret < 0 || ret != cmd->data_length) {
 368                                 pr_err("%s() returned %d, expecting %u for "
 369                                                 "S_ISBLK\n", __func__, ret,
 370                                                 cmd->data_length);
 371                                 return (ret < 0 ? ret : -EINVAL);
 372                         }
 373                 } else {
 374                         if (ret < 0) {
 375                                 pr_err("%s() returned %d for non S_ISBLK\n",
 376                                                 __func__, ret);
 377                                 return ret;
 378                         }
 379                 }
 380         }
 381         return 1;
 382 }
 383
 384 static sense_reason_t
 385 fd_execute_sync_cache(struct se_cmd *cmd)
 386 {
 387         struct se_device *dev = cmd->se_dev;
 388         struct fd_dev *fd_dev = FD_DEV(dev);
 389         int immed = (cmd->t_task_cdb[1] & 0x2);
 390         loff_t start, end;
 391         int ret;
 392
 393         /*
 394          * If the Immediate bit is set, queue up the GOOD response
 395          * for this SYNCHRONIZE_CACHE op
 396          */
 397         if (immed)
 398                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 399
 400         /*
 401          * Determine if we will be flushing the entire device.
 402          */
 403         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 404                 start = 0;
 405                 end = LLONG_MAX;
 406         } else {
 407                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 408                 if (cmd->data_length)
 409                         end = start + cmd->data_length - 1;
 410                 else
 411                         end = LLONG_MAX;
 412         }
 413
 414         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 415         if (ret != 0)
 416                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 417
 418         if (immed)
 419                 return 0;
 420
 421         if (ret)
 422                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 423         else
 424                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 425
 426         return 0;
 427 }
 428
 429 static sense_reason_t
 430 fd_execute_write_same(struct se_cmd *cmd)
 431 {
 432         struct se_device *se_dev = cmd->se_dev;
 433         struct fd_dev *fd_dev = FD_DEV(se_dev);
 434         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 435         sector_t nolb = sbc_get_write_same_sectors(cmd);
 436         struct iov_iter iter;
 437         struct bio_vec *bvec;
 438         unsigned int len = 0, i;
 439         ssize_t ret;
 440
 441         if (!nolb) {
 442                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 443                 return 0;
 444         }
 445         if (cmd->prot_op) {
 446                 pr_err("WRITE_SAME: Protection information with FILEIO"
 447                        " backends not supported\n");
 448                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 449         }
 450
 451         if (cmd->t_data_nents > 1 ||
 452             cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
 453                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 454                         " block_size: %u\n",
 455                         cmd->t_data_nents,
 456                         cmd->t_data_sg[0].length,
 457                         cmd->se_dev->dev_attrib.block_size);
 458                 return TCM_INVALID_CDB_FIELD;
 459         }
 460
 461         bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
 462         if (!bvec)
 463                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 464
 465         for (i = 0; i < nolb; i++) {
 466                 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
 467                 bvec[i].bv_len = cmd->t_data_sg[0].length;
 468                 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
 469
 470                 len += se_dev->dev_attrib.block_size;
 471         }
 472
 473         iov_iter_bvec(&iter, ITER_BVEC, bvec, nolb, len);
 474         ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos);
 475
 476         kfree(bvec);
 477         if (ret < 0 || ret != len) {
 478                 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
 479                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 480         }
 481
 482         target_complete_cmd(cmd, SAM_STAT_GOOD);
 483         return 0;
 484 }
 485
 486 static int
 487 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
 488                 void *buf, size_t bufsize)
 489 {
 490         struct fd_dev *fd_dev = FD_DEV(se_dev);
 491         struct file *prot_fd = fd_dev->fd_prot_file;
 492         sector_t prot_length, prot;
 493         loff_t pos = lba * se_dev->prot_length;
 494
 495         if (!prot_fd) {
 496                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 497                 return -ENODEV;
 498         }
 499
 500         prot_length = nolb * se_dev->prot_length;
 501
 502         for (prot = 0; prot < prot_length;) {
 503                 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
 504                 ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
 505
 506                 if (ret != len) {
 507                         pr_err("vfs_write to prot file failed: %zd\n", ret);
 508                         return ret < 0 ? ret : -ENODEV;
 509                 }
 510                 prot += ret;
 511         }
 512
 513         return 0;
 514 }
 515
 516 static int
 517 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
 518 {
 519         void *buf;
 520         int rc;
 521
 522         buf = (void *)__get_free_page(GFP_KERNEL);
 523         if (!buf) {
 524                 pr_err("Unable to allocate FILEIO prot buf\n");
 525                 return -ENOMEM;
 526         }
 527         memset(buf, 0xff, PAGE_SIZE);
 528
 529         rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
 530
 531         free_page((unsigned long)buf);
 532
 533         return rc;
 534 }
 535
 536 static sense_reason_t
 537 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 538 {
 539         struct file *file = priv;
 540         struct inode *inode = file->f_mapping->host;
 541         int ret;
 542
 543         if (cmd->se_dev->dev_attrib.pi_prot_type) {
 544                 ret = fd_do_prot_unmap(cmd, lba, nolb);
 545                 if (ret)
 546                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 547         }
 548
 549         if (S_ISBLK(inode->i_mode)) {
 550                 /* The backend is block device, use discard */
 551                 struct block_device *bdev = inode->i_bdev;
 552
 553                 ret = blkdev_issue_discard(bdev, lba,
 554                                 nolb, GFP_KERNEL, 0);
 555                 if (ret < 0) {
 556                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 557                                 ret);
 558                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 559                 }
 560         } else {
 561                 /* The backend is normal file, use fallocate */
 562                 struct se_device *se_dev = cmd->se_dev;
 563                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 564                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 565                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 566
 567                 if (!file->f_op->fallocate)
 568                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 569
 570                 ret = file->f_op->fallocate(file, mode, pos, len);
 571                 if (ret < 0) {
 572                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 573                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 574                 }
 575         }
 576
 577         return 0;
 578 }
 579
 580 static sense_reason_t
 581 fd_execute_write_same_unmap(struct se_cmd *cmd)
 582 {
 583         struct se_device *se_dev = cmd->se_dev;
 584         struct fd_dev *fd_dev = FD_DEV(se_dev);
 585         struct file *file = fd_dev->fd_file;
 586         sector_t lba = cmd->t_task_lba;
 587         sector_t nolb = sbc_get_write_same_sectors(cmd);
 588         sense_reason_t ret;
 589
 590         if (!nolb) {
 591                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 592                 return 0;
 593         }
 594
 595         ret = fd_do_unmap(cmd, file, lba, nolb);
 596         if (ret)
 597                 return ret;
 598
 599         target_complete_cmd(cmd, GOOD);
 600         return 0;
 601 }
 602
 603 static sense_reason_t
 604 fd_execute_unmap(struct se_cmd *cmd)
 605 {
 606         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 607
 608         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 609 }
 610
 611 static sense_reason_t
 612 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 613               enum dma_data_direction data_direction)
 614 {
 615         struct se_device *dev = cmd->se_dev;
 616         struct fd_prot fd_prot;
 617         sense_reason_t rc;
 618         int ret = 0;
 619         /*
 620          * We are currently limited by the number of iovecs (2048) per
 621          * single vfs_[writev,readv] call.
 622          */
 623         if (cmd->data_length > FD_MAX_BYTES) {
 624                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 625                        "FD_MAX_BYTES: %u iovec count limitiation\n",
 626                         cmd->data_length, FD_MAX_BYTES);
 627                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 628         }
 629         /*
 630          * Call vectorized fileio functions to map struct scatterlist
 631          * physical memory addresses to struct iovec virtual memory.
 632          */
 633         if (data_direction == DMA_FROM_DEVICE) {
 634                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 635
 636                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 637                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 638                         if (ret < 0)
 639                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 640                 }
 641
 642                 ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
 643
 644                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 645                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 646
 647                         rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
 648                                                  0, fd_prot.prot_sg, 0);
 649                         if (rc) {
 650                                 kfree(fd_prot.prot_sg);
 651                                 kfree(fd_prot.prot_buf);
 652                                 return rc;
 653                         }
 654                         kfree(fd_prot.prot_sg);
 655                         kfree(fd_prot.prot_buf);
 656                 }
 657         } else {
 658                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 659
 660                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 661                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 662
 663                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 664                         if (ret < 0)
 665                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 666
 667                         rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
 668                                                   0, fd_prot.prot_sg, 0);
 669                         if (rc) {
 670                                 kfree(fd_prot.prot_sg);
 671                                 kfree(fd_prot.prot_buf);
 672                                 return rc;
 673                         }
 674                 }
 675
 676                 ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
 677                 /*
 678                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 679                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 680                  * Allow this to happen independent of WCE=0 setting.
 681                  */
 682                 if (ret > 0 &&
 683                     dev->dev_attrib.emulate_fua_write > 0 &&
 684                     (cmd->se_cmd_flags & SCF_FUA)) {
 685                         struct fd_dev *fd_dev = FD_DEV(dev);
 686                         loff_t start = cmd->t_task_lba *
 687                                 dev->dev_attrib.block_size;
 688                         loff_t end;
 689
 690                         if (cmd->data_length)
 691                                 end = start + cmd->data_length - 1;
 692                         else
 693                                 end = LLONG_MAX;
 694
 695                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 696                 }
 697
 698                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 699                         ret = fd_do_prot_rw(cmd, &fd_prot, true);
 700                         if (ret < 0)
 701                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 702                 }
 703         }
 704
 705         if (ret < 0) {
 706                 kfree(fd_prot.prot_sg);
 707                 kfree(fd_prot.prot_buf);
 708                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 709         }
 710
 711         if (ret)
 712                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 713         return 0;
 714 }
 715
 716 enum {
 717         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 718 };
 719
 720 static match_table_t tokens = {
 721         {Opt_fd_dev_name, "fd_dev_name=%s"},
 722         {Opt_fd_dev_size, "fd_dev_size=%s"},
 723         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 724         {Opt_err, NULL}
 725 };
 726
 727 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 728                 const char *page, ssize_t count)
 729 {
 730         struct fd_dev *fd_dev = FD_DEV(dev);
 731         char *orig, *ptr, *arg_p, *opts;
 732         substring_t args[MAX_OPT_ARGS];
 733         int ret = 0, arg, token;
 734
 735         opts = kstrdup(page, GFP_KERNEL);
 736         if (!opts)
 737                 return -ENOMEM;
 738
 739         orig = opts;
 740
 741         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 742                 if (!*ptr)
 743                         continue;
 744
 745                 token = match_token(ptr, tokens, args);
 746                 switch (token) {
 747                 case Opt_fd_dev_name:
 748                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 749                                 FD_MAX_DEV_NAME) == 0) {
 750                                 ret = -EINVAL;
 751                                 break;
 752                         }
 753                         pr_debug("FILEIO: Referencing Path: %s\n",
 754                                         fd_dev->fd_dev_name);
 755                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 756                         break;
 757                 case Opt_fd_dev_size:
 758                         arg_p = match_strdup(&args[0]);
 759                         if (!arg_p) {
 760                                 ret = -ENOMEM;
 761                                 break;
 762                         }
 763                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 764                         kfree(arg_p);
 765                         if (ret < 0) {
 766                                 pr_err("kstrtoull() failed for"
 767                                                 " fd_dev_size=\n");
 768                                 goto out;
 769                         }
 770                         pr_debug("FILEIO: Referencing Size: %llu"
 771                                         " bytes\n", fd_dev->fd_dev_size);
 772                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 773                         break;
 774                 case Opt_fd_buffered_io:
 775                         ret = match_int(args, &arg);
 776                         if (ret)
 777                                 goto out;
 778                         if (arg != 1) {
 779                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 780                                 ret = -EINVAL;
 781                                 goto out;
 782                         }
 783
 784                         pr_debug("FILEIO: Using buffered I/O"
 785                                 " operations for struct fd_dev\n");
 786
 787                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 788                         break;
 789                 default:
 790                         break;
 791                 }
 792         }
 793
 794 out:
 795         kfree(orig);
 796         return (!ret) ? count : ret;
 797 }
 798
 799 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 800 {
 801         struct fd_dev *fd_dev = FD_DEV(dev);
 802         ssize_t bl = 0;
 803
 804         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 805         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 806                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 807                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 808                 "Buffered-WCE" : "O_DSYNC");
 809         return bl;
 810 }
 811
 812 static sector_t fd_get_blocks(struct se_device *dev)
 813 {
 814         struct fd_dev *fd_dev = FD_DEV(dev);
 815         struct file *f = fd_dev->fd_file;
 816         struct inode *i = f->f_mapping->host;
 817         unsigned long long dev_size;
 818         /*
 819          * When using a file that references an underlying struct block_device,
 820          * ensure dev_size is always based on the current inode size in order
 821          * to handle underlying block_device resize operations.
 822          */
 823         if (S_ISBLK(i->i_mode))
 824                 dev_size = i_size_read(i);
 825         else
 826                 dev_size = fd_dev->fd_dev_size;
 827
 828         return div_u64(dev_size - dev->dev_attrib.block_size,
 829                        dev->dev_attrib.block_size);
 830 }
 831
 832 static int fd_init_prot(struct se_device *dev)
 833 {
 834         struct fd_dev *fd_dev = FD_DEV(dev);
 835         struct file *prot_file, *file = fd_dev->fd_file;
 836         struct inode *inode;
 837         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 838         char buf[FD_MAX_DEV_PROT_NAME];
 839
 840         if (!file) {
 841                 pr_err("Unable to locate fd_dev->fd_file\n");
 842                 return -ENODEV;
 843         }
 844
 845         inode = file->f_mapping->host;
 846         if (S_ISBLK(inode->i_mode)) {
 847                 pr_err("FILEIO Protection emulation only supported on"
 848                        " !S_ISBLK\n");
 849                 return -ENOSYS;
 850         }
 851
 852         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 853                 flags &= ~O_DSYNC;
 854
 855         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 856                  fd_dev->fd_dev_name);
 857
 858         prot_file = filp_open(buf, flags, 0600);
 859         if (IS_ERR(prot_file)) {
 860                 pr_err("filp_open(%s) failed\n", buf);
 861                 ret = PTR_ERR(prot_file);
 862                 return ret;
 863         }
 864         fd_dev->fd_prot_file = prot_file;
 865
 866         return 0;
 867 }
 868
 869 static int fd_format_prot(struct se_device *dev)
 870 {
 871         unsigned char *buf;
 872         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 873         int ret;
 874
 875         if (!dev->dev_attrib.pi_prot_type) {
 876                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 877                 return -ENODEV;
 878         }
 879
 880         buf = vzalloc(unit_size);
 881         if (!buf) {
 882                 pr_err("Unable to allocate FILEIO prot buf\n");
 883                 return -ENOMEM;
 884         }
 885
 886         pr_debug("Using FILEIO prot_length: %llu\n",
 887                  (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
 888                                         dev->prot_length);
 889
 890         memset(buf, 0xff, unit_size);
 891         ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
 892                               buf, unit_size);
 893         vfree(buf);
 894         return ret;
 895 }
 896
 897 static void fd_free_prot(struct se_device *dev)
 898 {
 899         struct fd_dev *fd_dev = FD_DEV(dev);
 900
 901         if (!fd_dev->fd_prot_file)
 902                 return;
 903
 904         filp_close(fd_dev->fd_prot_file, NULL);
 905         fd_dev->fd_prot_file = NULL;
 906 }
 907
 908 static struct sbc_ops fd_sbc_ops = {
 909         .execute_rw             = fd_execute_rw,
 910         .execute_sync_cache     = fd_execute_sync_cache,
 911         .execute_write_same     = fd_execute_write_same,
 912         .execute_write_same_unmap = fd_execute_write_same_unmap,
 913         .execute_unmap          = fd_execute_unmap,
 914 };
 915
 916 static sense_reason_t
 917 fd_parse_cdb(struct se_cmd *cmd)
 918 {
 919         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 920 }
 921
 922 DEF_TB_DEFAULT_ATTRIBS(fileio);
 923
 924 static struct configfs_attribute *fileio_backend_dev_attrs[] = {
 925         &fileio_dev_attrib_emulate_model_alias.attr,
 926         &fileio_dev_attrib_emulate_dpo.attr,
 927         &fileio_dev_attrib_emulate_fua_write.attr,
 928         &fileio_dev_attrib_emulate_fua_read.attr,
 929         &fileio_dev_attrib_emulate_write_cache.attr,
 930         &fileio_dev_attrib_emulate_ua_intlck_ctrl.attr,
 931         &fileio_dev_attrib_emulate_tas.attr,
 932         &fileio_dev_attrib_emulate_tpu.attr,
 933         &fileio_dev_attrib_emulate_tpws.attr,
 934         &fileio_dev_attrib_emulate_caw.attr,
 935         &fileio_dev_attrib_emulate_3pc.attr,
 936         &fileio_dev_attrib_pi_prot_type.attr,
 937         &fileio_dev_attrib_hw_pi_prot_type.attr,
 938         &fileio_dev_attrib_pi_prot_format.attr,
 939         &fileio_dev_attrib_enforce_pr_isids.attr,
 940         &fileio_dev_attrib_is_nonrot.attr,
 941         &fileio_dev_attrib_emulate_rest_reord.attr,
 942         &fileio_dev_attrib_force_pr_aptpl.attr,
 943         &fileio_dev_attrib_hw_block_size.attr,
 944         &fileio_dev_attrib_block_size.attr,
 945         &fileio_dev_attrib_hw_max_sectors.attr,
 946         &fileio_dev_attrib_optimal_sectors.attr,
 947         &fileio_dev_attrib_hw_queue_depth.attr,
 948         &fileio_dev_attrib_queue_depth.attr,
 949         &fileio_dev_attrib_max_unmap_lba_count.attr,
 950         &fileio_dev_attrib_max_unmap_block_desc_count.attr,
 951         &fileio_dev_attrib_unmap_granularity.attr,
 952         &fileio_dev_attrib_unmap_granularity_alignment.attr,
 953         &fileio_dev_attrib_max_write_same_len.attr,
 954         NULL,
 955 };
 956
 957 static struct se_subsystem_api fileio_template = {
 958         .name                   = "fileio",
 959         .inquiry_prod           = "FILEIO",
 960         .inquiry_rev            = FD_VERSION,
 961         .owner                  = THIS_MODULE,
 962         .attach_hba             = fd_attach_hba,
 963         .detach_hba             = fd_detach_hba,
 964         .alloc_device           = fd_alloc_device,
 965         .configure_device       = fd_configure_device,
 966         .free_device            = fd_free_device,
 967         .parse_cdb              = fd_parse_cdb,
 968         .set_configfs_dev_params = fd_set_configfs_dev_params,
 969         .show_configfs_dev_params = fd_show_configfs_dev_params,
 970         .get_device_type        = sbc_get_device_type,
 971         .get_blocks             = fd_get_blocks,
 972         .init_prot              = fd_init_prot,
 973         .format_prot            = fd_format_prot,
 974         .free_prot              = fd_free_prot,
 975 };
 976
 977 static int __init fileio_module_init(void)
 978 {
 979         struct target_backend_cits *tbc = &fileio_template.tb_cits;
 980
 981         target_core_setup_sub_cits(&fileio_template);
 982         tbc->tb_dev_attrib_cit.ct_attrs = fileio_backend_dev_attrs;
 983
 984         return transport_subsystem_register(&fileio_template);
 985 }
 986
 987 static void __exit fileio_module_exit(void)
 988 {
 989         transport_subsystem_release(&fileio_template);
 990 }
 991
 992 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
 993 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 994 MODULE_LICENSE("GPL");
 995
 996 module_init(fileio_module_init);
 997 module_exit(fileio_module_exit);