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_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
 262                          int is_write)
 263 {
 264         struct se_device *se_dev = cmd->se_dev;
 265         struct fd_dev *dev = FD_DEV(se_dev);
 266         struct file *prot_fd = dev->fd_prot_file;
 267         loff_t pos = (cmd->t_task_lba * se_dev->prot_length);
 268         unsigned char *buf;
 269         u32 prot_size;
 270         int rc, ret = 1;
 271
 272         prot_size = (cmd->data_length / se_dev->dev_attrib.block_size) *
 273                      se_dev->prot_length;
 274
 275         if (!is_write) {
 276                 fd_prot->prot_buf = kzalloc(prot_size, GFP_KERNEL);
 277                 if (!fd_prot->prot_buf) {
 278                         pr_err("Unable to allocate fd_prot->prot_buf\n");
 279                         return -ENOMEM;
 280                 }
 281                 buf = fd_prot->prot_buf;
 282
 283                 fd_prot->prot_sg_nents = 1;
 284                 fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist),
 285                                            GFP_KERNEL);
 286                 if (!fd_prot->prot_sg) {
 287                         pr_err("Unable to allocate fd_prot->prot_sg\n");
 288                         kfree(fd_prot->prot_buf);
 289                         return -ENOMEM;
 290                 }
 291                 sg_init_table(fd_prot->prot_sg, fd_prot->prot_sg_nents);
 292                 sg_set_buf(fd_prot->prot_sg, buf, prot_size);
 293         }
 294
 295         if (is_write) {
 296                 rc = kernel_write(prot_fd, fd_prot->prot_buf, prot_size, pos);
 297                 if (rc < 0 || prot_size != rc) {
 298                         pr_err("kernel_write() for fd_do_prot_rw failed:"
 299                                " %d\n", rc);
 300                         ret = -EINVAL;
 301                 }
 302         } else {
 303                 rc = kernel_read(prot_fd, pos, fd_prot->prot_buf, prot_size);
 304                 if (rc < 0) {
 305                         pr_err("kernel_read() for fd_do_prot_rw failed:"
 306                                " %d\n", rc);
 307                         ret = -EINVAL;
 308                 }
 309         }
 310
 311         if (is_write || ret < 0) {
 312                 kfree(fd_prot->prot_sg);
 313                 kfree(fd_prot->prot_buf);
 314         }
 315
 316         return ret;
 317 }
 318
 319 static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
 320                 u32 sgl_nents, int is_write)
 321 {
 322         struct se_device *se_dev = cmd->se_dev;
 323         struct fd_dev *dev = FD_DEV(se_dev);
 324         struct file *fd = dev->fd_file;
 325         struct scatterlist *sg;
 326         struct iov_iter iter;
 327         struct bio_vec *bvec;
 328         ssize_t len = 0;
 329         loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
 330         int ret = 0, i;
 331
 332         bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
 333         if (!bvec) {
 334                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 335                 return -ENOMEM;
 336         }
 337
 338         for_each_sg(sgl, sg, sgl_nents, i) {
 339                 bvec[i].bv_page = sg_page(sg);
 340                 bvec[i].bv_len = sg->length;
 341                 bvec[i].bv_offset = sg->offset;
 342
 343                 len += sg->length;
 344         }
 345
 346         iov_iter_bvec(&iter, ITER_BVEC, bvec, sgl_nents, len);
 347         if (is_write)
 348                 ret = vfs_iter_write(fd, &iter, &pos);
 349         else
 350                 ret = vfs_iter_read(fd, &iter, &pos);
 351
 352         kfree(bvec);
 353
 354         if (is_write) {
 355                 if (ret < 0 || ret != cmd->data_length) {
 356                         pr_err("%s() write returned %d\n", __func__, ret);
 357                         return (ret < 0 ? ret : -EINVAL);
 358                 }
 359         } else {
 360                 /*
 361                  * Return zeros and GOOD status even if the READ did not return
 362                  * the expected virt_size for struct file w/o a backing struct
 363                  * block_device.
 364                  */
 365                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 366                         if (ret < 0 || ret != cmd->data_length) {
 367                                 pr_err("%s() returned %d, expecting %u for "
 368                                                 "S_ISBLK\n", __func__, ret,
 369                                                 cmd->data_length);
 370                                 return (ret < 0 ? ret : -EINVAL);
 371                         }
 372                 } else {
 373                         if (ret < 0) {
 374                                 pr_err("%s() returned %d for non S_ISBLK\n",
 375                                                 __func__, ret);
 376                                 return ret;
 377                         }
 378                 }
 379         }
 380         return 1;
 381 }
 382
 383 static sense_reason_t
 384 fd_execute_sync_cache(struct se_cmd *cmd)
 385 {
 386         struct se_device *dev = cmd->se_dev;
 387         struct fd_dev *fd_dev = FD_DEV(dev);
 388         int immed = (cmd->t_task_cdb[1] & 0x2);
 389         loff_t start, end;
 390         int ret;
 391
 392         /*
 393          * If the Immediate bit is set, queue up the GOOD response
 394          * for this SYNCHRONIZE_CACHE op
 395          */
 396         if (immed)
 397                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 398
 399         /*
 400          * Determine if we will be flushing the entire device.
 401          */
 402         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 403                 start = 0;
 404                 end = LLONG_MAX;
 405         } else {
 406                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 407                 if (cmd->data_length)
 408                         end = start + cmd->data_length - 1;
 409                 else
 410                         end = LLONG_MAX;
 411         }
 412
 413         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 414         if (ret != 0)
 415                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 416
 417         if (immed)
 418                 return 0;
 419
 420         if (ret)
 421                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 422         else
 423                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 424
 425         return 0;
 426 }
 427
 428 static sense_reason_t
 429 fd_execute_write_same(struct se_cmd *cmd)
 430 {
 431         struct se_device *se_dev = cmd->se_dev;
 432         struct fd_dev *fd_dev = FD_DEV(se_dev);
 433         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 434         sector_t nolb = sbc_get_write_same_sectors(cmd);
 435         struct iov_iter iter;
 436         struct bio_vec *bvec;
 437         unsigned int len = 0, i;
 438         ssize_t ret;
 439
 440         if (!nolb) {
 441                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 442                 return 0;
 443         }
 444         if (cmd->prot_op) {
 445                 pr_err("WRITE_SAME: Protection information with FILEIO"
 446                        " backends not supported\n");
 447                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 448         }
 449
 450         if (cmd->t_data_nents > 1 ||
 451             cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
 452                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 453                         " block_size: %u\n",
 454                         cmd->t_data_nents,
 455                         cmd->t_data_sg[0].length,
 456                         cmd->se_dev->dev_attrib.block_size);
 457                 return TCM_INVALID_CDB_FIELD;
 458         }
 459
 460         bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
 461         if (!bvec)
 462                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 463
 464         for (i = 0; i < nolb; i++) {
 465                 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
 466                 bvec[i].bv_len = cmd->t_data_sg[0].length;
 467                 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
 468
 469                 len += se_dev->dev_attrib.block_size;
 470         }
 471
 472         iov_iter_bvec(&iter, ITER_BVEC, bvec, nolb, len);
 473         ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos);
 474
 475         kfree(bvec);
 476         if (ret < 0 || ret != len) {
 477                 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
 478                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 479         }
 480
 481         target_complete_cmd(cmd, SAM_STAT_GOOD);
 482         return 0;
 483 }
 484
 485 static int
 486 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
 487                 void *buf, size_t bufsize)
 488 {
 489         struct fd_dev *fd_dev = FD_DEV(se_dev);
 490         struct file *prot_fd = fd_dev->fd_prot_file;
 491         sector_t prot_length, prot;
 492         loff_t pos = lba * se_dev->prot_length;
 493
 494         if (!prot_fd) {
 495                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 496                 return -ENODEV;
 497         }
 498
 499         prot_length = nolb * se_dev->prot_length;
 500
 501         for (prot = 0; prot < prot_length;) {
 502                 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
 503                 ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
 504
 505                 if (ret != len) {
 506                         pr_err("vfs_write to prot file failed: %zd\n", ret);
 507                         return ret < 0 ? ret : -ENODEV;
 508                 }
 509                 prot += ret;
 510         }
 511
 512         return 0;
 513 }
 514
 515 static int
 516 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
 517 {
 518         void *buf;
 519         int rc;
 520
 521         buf = (void *)__get_free_page(GFP_KERNEL);
 522         if (!buf) {
 523                 pr_err("Unable to allocate FILEIO prot buf\n");
 524                 return -ENOMEM;
 525         }
 526         memset(buf, 0xff, PAGE_SIZE);
 527
 528         rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
 529
 530         free_page((unsigned long)buf);
 531
 532         return rc;
 533 }
 534
 535 static sense_reason_t
 536 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 537 {
 538         struct file *file = priv;
 539         struct inode *inode = file->f_mapping->host;
 540         int ret;
 541
 542         if (cmd->se_dev->dev_attrib.pi_prot_type) {
 543                 ret = fd_do_prot_unmap(cmd, lba, nolb);
 544                 if (ret)
 545                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 546         }
 547
 548         if (S_ISBLK(inode->i_mode)) {
 549                 /* The backend is block device, use discard */
 550                 struct block_device *bdev = inode->i_bdev;
 551
 552                 ret = blkdev_issue_discard(bdev, lba,
 553                                 nolb, GFP_KERNEL, 0);
 554                 if (ret < 0) {
 555                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 556                                 ret);
 557                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 558                 }
 559         } else {
 560                 /* The backend is normal file, use fallocate */
 561                 struct se_device *se_dev = cmd->se_dev;
 562                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 563                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 564                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 565
 566                 if (!file->f_op->fallocate)
 567                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 568
 569                 ret = file->f_op->fallocate(file, mode, pos, len);
 570                 if (ret < 0) {
 571                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 572                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 573                 }
 574         }
 575
 576         return 0;
 577 }
 578
 579 static sense_reason_t
 580 fd_execute_write_same_unmap(struct se_cmd *cmd)
 581 {
 582         struct se_device *se_dev = cmd->se_dev;
 583         struct fd_dev *fd_dev = FD_DEV(se_dev);
 584         struct file *file = fd_dev->fd_file;
 585         sector_t lba = cmd->t_task_lba;
 586         sector_t nolb = sbc_get_write_same_sectors(cmd);
 587         sense_reason_t ret;
 588
 589         if (!nolb) {
 590                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 591                 return 0;
 592         }
 593
 594         ret = fd_do_unmap(cmd, file, lba, nolb);
 595         if (ret)
 596                 return ret;
 597
 598         target_complete_cmd(cmd, GOOD);
 599         return 0;
 600 }
 601
 602 static sense_reason_t
 603 fd_execute_unmap(struct se_cmd *cmd)
 604 {
 605         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 606
 607         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 608 }
 609
 610 static sense_reason_t
 611 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 612               enum dma_data_direction data_direction)
 613 {
 614         struct se_device *dev = cmd->se_dev;
 615         struct fd_prot fd_prot;
 616         sense_reason_t rc;
 617         int ret = 0;
 618         /*
 619          * We are currently limited by the number of iovecs (2048) per
 620          * single vfs_[writev,readv] call.
 621          */
 622         if (cmd->data_length > FD_MAX_BYTES) {
 623                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 624                        "FD_MAX_BYTES: %u iovec count limitiation\n",
 625                         cmd->data_length, FD_MAX_BYTES);
 626                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 627         }
 628         /*
 629          * Call vectorized fileio functions to map struct scatterlist
 630          * physical memory addresses to struct iovec virtual memory.
 631          */
 632         if (data_direction == DMA_FROM_DEVICE) {
 633                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 634
 635                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 636                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 637                         if (ret < 0)
 638                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 639                 }
 640
 641                 ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
 642
 643                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 644                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 645
 646                         rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
 647                                                  0, fd_prot.prot_sg, 0);
 648                         if (rc) {
 649                                 kfree(fd_prot.prot_sg);
 650                                 kfree(fd_prot.prot_buf);
 651                                 return rc;
 652                         }
 653                         kfree(fd_prot.prot_sg);
 654                         kfree(fd_prot.prot_buf);
 655                 }
 656         } else {
 657                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 658
 659                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 660                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 661
 662                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 663                         if (ret < 0)
 664                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 665
 666                         rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
 667                                                   0, fd_prot.prot_sg, 0);
 668                         if (rc) {
 669                                 kfree(fd_prot.prot_sg);
 670                                 kfree(fd_prot.prot_buf);
 671                                 return rc;
 672                         }
 673                 }
 674
 675                 ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
 676                 /*
 677                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 678                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 679                  * Allow this to happen independent of WCE=0 setting.
 680                  */
 681                 if (ret > 0 &&
 682                     dev->dev_attrib.emulate_fua_write > 0 &&
 683                     (cmd->se_cmd_flags & SCF_FUA)) {
 684                         struct fd_dev *fd_dev = FD_DEV(dev);
 685                         loff_t start = cmd->t_task_lba *
 686                                 dev->dev_attrib.block_size;
 687                         loff_t end;
 688
 689                         if (cmd->data_length)
 690                                 end = start + cmd->data_length - 1;
 691                         else
 692                                 end = LLONG_MAX;
 693
 694                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 695                 }
 696
 697                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 698                         ret = fd_do_prot_rw(cmd, &fd_prot, true);
 699                         if (ret < 0)
 700                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 701                 }
 702         }
 703
 704         if (ret < 0) {
 705                 kfree(fd_prot.prot_sg);
 706                 kfree(fd_prot.prot_buf);
 707                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 708         }
 709
 710         if (ret)
 711                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 712         return 0;
 713 }
 714
 715 enum {
 716         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 717 };
 718
 719 static match_table_t tokens = {
 720         {Opt_fd_dev_name, "fd_dev_name=%s"},
 721         {Opt_fd_dev_size, "fd_dev_size=%s"},
 722         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 723         {Opt_err, NULL}
 724 };
 725
 726 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 727                 const char *page, ssize_t count)
 728 {
 729         struct fd_dev *fd_dev = FD_DEV(dev);
 730         char *orig, *ptr, *arg_p, *opts;
 731         substring_t args[MAX_OPT_ARGS];
 732         int ret = 0, arg, token;
 733
 734         opts = kstrdup(page, GFP_KERNEL);
 735         if (!opts)
 736                 return -ENOMEM;
 737
 738         orig = opts;
 739
 740         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 741                 if (!*ptr)
 742                         continue;
 743
 744                 token = match_token(ptr, tokens, args);
 745                 switch (token) {
 746                 case Opt_fd_dev_name:
 747                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 748                                 FD_MAX_DEV_NAME) == 0) {
 749                                 ret = -EINVAL;
 750                                 break;
 751                         }
 752                         pr_debug("FILEIO: Referencing Path: %s\n",
 753                                         fd_dev->fd_dev_name);
 754                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 755                         break;
 756                 case Opt_fd_dev_size:
 757                         arg_p = match_strdup(&args[0]);
 758                         if (!arg_p) {
 759                                 ret = -ENOMEM;
 760                                 break;
 761                         }
 762                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 763                         kfree(arg_p);
 764                         if (ret < 0) {
 765                                 pr_err("kstrtoull() failed for"
 766                                                 " fd_dev_size=\n");
 767                                 goto out;
 768                         }
 769                         pr_debug("FILEIO: Referencing Size: %llu"
 770                                         " bytes\n", fd_dev->fd_dev_size);
 771                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 772                         break;
 773                 case Opt_fd_buffered_io:
 774                         ret = match_int(args, &arg);
 775                         if (ret)
 776                                 goto out;
 777                         if (arg != 1) {
 778                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 779                                 ret = -EINVAL;
 780                                 goto out;
 781                         }
 782
 783                         pr_debug("FILEIO: Using buffered I/O"
 784                                 " operations for struct fd_dev\n");
 785
 786                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 787                         break;
 788                 default:
 789                         break;
 790                 }
 791         }
 792
 793 out:
 794         kfree(orig);
 795         return (!ret) ? count : ret;
 796 }
 797
 798 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 799 {
 800         struct fd_dev *fd_dev = FD_DEV(dev);
 801         ssize_t bl = 0;
 802
 803         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 804         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 805                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 806                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 807                 "Buffered-WCE" : "O_DSYNC");
 808         return bl;
 809 }
 810
 811 static sector_t fd_get_blocks(struct se_device *dev)
 812 {
 813         struct fd_dev *fd_dev = FD_DEV(dev);
 814         struct file *f = fd_dev->fd_file;
 815         struct inode *i = f->f_mapping->host;
 816         unsigned long long dev_size;
 817         /*
 818          * When using a file that references an underlying struct block_device,
 819          * ensure dev_size is always based on the current inode size in order
 820          * to handle underlying block_device resize operations.
 821          */
 822         if (S_ISBLK(i->i_mode))
 823                 dev_size = i_size_read(i);
 824         else
 825                 dev_size = fd_dev->fd_dev_size;
 826
 827         return div_u64(dev_size - dev->dev_attrib.block_size,
 828                        dev->dev_attrib.block_size);
 829 }
 830
 831 static int fd_init_prot(struct se_device *dev)
 832 {
 833         struct fd_dev *fd_dev = FD_DEV(dev);
 834         struct file *prot_file, *file = fd_dev->fd_file;
 835         struct inode *inode;
 836         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 837         char buf[FD_MAX_DEV_PROT_NAME];
 838
 839         if (!file) {
 840                 pr_err("Unable to locate fd_dev->fd_file\n");
 841                 return -ENODEV;
 842         }
 843
 844         inode = file->f_mapping->host;
 845         if (S_ISBLK(inode->i_mode)) {
 846                 pr_err("FILEIO Protection emulation only supported on"
 847                        " !S_ISBLK\n");
 848                 return -ENOSYS;
 849         }
 850
 851         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 852                 flags &= ~O_DSYNC;
 853
 854         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 855                  fd_dev->fd_dev_name);
 856
 857         prot_file = filp_open(buf, flags, 0600);
 858         if (IS_ERR(prot_file)) {
 859                 pr_err("filp_open(%s) failed\n", buf);
 860                 ret = PTR_ERR(prot_file);
 861                 return ret;
 862         }
 863         fd_dev->fd_prot_file = prot_file;
 864
 865         return 0;
 866 }
 867
 868 static int fd_format_prot(struct se_device *dev)
 869 {
 870         unsigned char *buf;
 871         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 872         int ret;
 873
 874         if (!dev->dev_attrib.pi_prot_type) {
 875                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 876                 return -ENODEV;
 877         }
 878
 879         buf = vzalloc(unit_size);
 880         if (!buf) {
 881                 pr_err("Unable to allocate FILEIO prot buf\n");
 882                 return -ENOMEM;
 883         }
 884
 885         pr_debug("Using FILEIO prot_length: %llu\n",
 886                  (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
 887                                         dev->prot_length);
 888
 889         memset(buf, 0xff, unit_size);
 890         ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
 891                               buf, unit_size);
 892         vfree(buf);
 893         return ret;
 894 }
 895
 896 static void fd_free_prot(struct se_device *dev)
 897 {
 898         struct fd_dev *fd_dev = FD_DEV(dev);
 899
 900         if (!fd_dev->fd_prot_file)
 901                 return;
 902
 903         filp_close(fd_dev->fd_prot_file, NULL);
 904         fd_dev->fd_prot_file = NULL;
 905 }
 906
 907 static struct sbc_ops fd_sbc_ops = {
 908         .execute_rw             = fd_execute_rw,
 909         .execute_sync_cache     = fd_execute_sync_cache,
 910         .execute_write_same     = fd_execute_write_same,
 911         .execute_write_same_unmap = fd_execute_write_same_unmap,
 912         .execute_unmap          = fd_execute_unmap,
 913 };
 914
 915 static sense_reason_t
 916 fd_parse_cdb(struct se_cmd *cmd)
 917 {
 918         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 919 }
 920
 921 DEF_TB_DEFAULT_ATTRIBS(fileio);
 922
 923 static struct configfs_attribute *fileio_backend_dev_attrs[] = {
 924         &fileio_dev_attrib_emulate_model_alias.attr,
 925         &fileio_dev_attrib_emulate_dpo.attr,
 926         &fileio_dev_attrib_emulate_fua_write.attr,
 927         &fileio_dev_attrib_emulate_fua_read.attr,
 928         &fileio_dev_attrib_emulate_write_cache.attr,
 929         &fileio_dev_attrib_emulate_ua_intlck_ctrl.attr,
 930         &fileio_dev_attrib_emulate_tas.attr,
 931         &fileio_dev_attrib_emulate_tpu.attr,
 932         &fileio_dev_attrib_emulate_tpws.attr,
 933         &fileio_dev_attrib_emulate_caw.attr,
 934         &fileio_dev_attrib_emulate_3pc.attr,
 935         &fileio_dev_attrib_pi_prot_type.attr,
 936         &fileio_dev_attrib_hw_pi_prot_type.attr,
 937         &fileio_dev_attrib_pi_prot_format.attr,
 938         &fileio_dev_attrib_enforce_pr_isids.attr,
 939         &fileio_dev_attrib_is_nonrot.attr,
 940         &fileio_dev_attrib_emulate_rest_reord.attr,
 941         &fileio_dev_attrib_force_pr_aptpl.attr,
 942         &fileio_dev_attrib_hw_block_size.attr,
 943         &fileio_dev_attrib_block_size.attr,
 944         &fileio_dev_attrib_hw_max_sectors.attr,
 945         &fileio_dev_attrib_optimal_sectors.attr,
 946         &fileio_dev_attrib_hw_queue_depth.attr,
 947         &fileio_dev_attrib_queue_depth.attr,
 948         &fileio_dev_attrib_max_unmap_lba_count.attr,
 949         &fileio_dev_attrib_max_unmap_block_desc_count.attr,
 950         &fileio_dev_attrib_unmap_granularity.attr,
 951         &fileio_dev_attrib_unmap_granularity_alignment.attr,
 952         &fileio_dev_attrib_max_write_same_len.attr,
 953         NULL,
 954 };
 955
 956 static struct se_subsystem_api fileio_template = {
 957         .name                   = "fileio",
 958         .inquiry_prod           = "FILEIO",
 959         .inquiry_rev            = FD_VERSION,
 960         .owner                  = THIS_MODULE,
 961         .attach_hba             = fd_attach_hba,
 962         .detach_hba             = fd_detach_hba,
 963         .alloc_device           = fd_alloc_device,
 964         .configure_device       = fd_configure_device,
 965         .free_device            = fd_free_device,
 966         .parse_cdb              = fd_parse_cdb,
 967         .set_configfs_dev_params = fd_set_configfs_dev_params,
 968         .show_configfs_dev_params = fd_show_configfs_dev_params,
 969         .get_device_type        = sbc_get_device_type,
 970         .get_blocks             = fd_get_blocks,
 971         .init_prot              = fd_init_prot,
 972         .format_prot            = fd_format_prot,
 973         .free_prot              = fd_free_prot,
 974 };
 975
 976 static int __init fileio_module_init(void)
 977 {
 978         struct target_backend_cits *tbc = &fileio_template.tb_cits;
 979
 980         target_core_setup_sub_cits(&fileio_template);
 981         tbc->tb_dev_attrib_cit.ct_attrs = fileio_backend_dev_attrs;
 982
 983         return transport_subsystem_register(&fileio_template);
 984 }
 985
 986 static void __exit fileio_module_exit(void)
 987 {
 988         transport_subsystem_release(&fileio_template);
 989 }
 990
 991 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
 992 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 993 MODULE_LICENSE("GPL");
 994
 995 module_init(fileio_module_init);
 996 module_exit(fileio_module_exit);