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         struct scatterlist *sg;
 268         loff_t pos = (cmd->t_task_lba * se_dev->prot_length);
 269         unsigned char *buf;
 270         u32 prot_size, len, size;
 271         int rc, ret = 1, i;
 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 = vzalloc(prot_size);
 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 = cmd->t_prot_nents;
 285                 fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist) *
 286                                            fd_prot->prot_sg_nents, GFP_KERNEL);
 287                 if (!fd_prot->prot_sg) {
 288                         pr_err("Unable to allocate fd_prot->prot_sg\n");
 289                         vfree(fd_prot->prot_buf);
 290                         return -ENOMEM;
 291                 }
 292                 size = prot_size;
 293
 294                 for_each_sg(fd_prot->prot_sg, sg, fd_prot->prot_sg_nents, i) {
 295
 296                         len = min_t(u32, PAGE_SIZE, size);
 297                         sg_set_buf(sg, buf, len);
 298                         size -= len;
 299                         buf += len;
 300                 }
 301         }
 302
 303         if (is_write) {
 304                 rc = kernel_write(prot_fd, fd_prot->prot_buf, prot_size, pos);
 305                 if (rc < 0 || prot_size != rc) {
 306                         pr_err("kernel_write() for fd_do_prot_rw failed:"
 307                                " %d\n", rc);
 308                         ret = -EINVAL;
 309                 }
 310         } else {
 311                 rc = kernel_read(prot_fd, pos, fd_prot->prot_buf, prot_size);
 312                 if (rc < 0) {
 313                         pr_err("kernel_read() for fd_do_prot_rw failed:"
 314                                " %d\n", rc);
 315                         ret = -EINVAL;
 316                 }
 317         }
 318
 319         if (is_write || ret < 0) {
 320                 kfree(fd_prot->prot_sg);
 321                 vfree(fd_prot->prot_buf);
 322         }
 323
 324         return ret;
 325 }
 326
 327 static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
 328                 u32 sgl_nents, int is_write)
 329 {
 330         struct se_device *se_dev = cmd->se_dev;
 331         struct fd_dev *dev = FD_DEV(se_dev);
 332         struct file *fd = dev->fd_file;
 333         struct scatterlist *sg;
 334         struct iovec *iov;
 335         mm_segment_t old_fs;
 336         loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
 337         int ret = 0, i;
 338
 339         iov = kzalloc(sizeof(struct iovec) * sgl_nents, GFP_KERNEL);
 340         if (!iov) {
 341                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 342                 return -ENOMEM;
 343         }
 344
 345         for_each_sg(sgl, sg, sgl_nents, i) {
 346                 iov[i].iov_len = sg->length;
 347                 iov[i].iov_base = kmap(sg_page(sg)) + sg->offset;
 348         }
 349
 350         old_fs = get_fs();
 351         set_fs(get_ds());
 352
 353         if (is_write)
 354                 ret = vfs_writev(fd, &iov[0], sgl_nents, &pos);
 355         else
 356                 ret = vfs_readv(fd, &iov[0], sgl_nents, &pos);
 357
 358         set_fs(old_fs);
 359
 360         for_each_sg(sgl, sg, sgl_nents, i)
 361                 kunmap(sg_page(sg));
 362
 363         kfree(iov);
 364
 365         if (is_write) {
 366                 if (ret < 0 || ret != cmd->data_length) {
 367                         pr_err("%s() write returned %d\n", __func__, ret);
 368                         return (ret < 0 ? ret : -EINVAL);
 369                 }
 370         } else {
 371                 /*
 372                  * Return zeros and GOOD status even if the READ did not return
 373                  * the expected virt_size for struct file w/o a backing struct
 374                  * block_device.
 375                  */
 376                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 377                         if (ret < 0 || ret != cmd->data_length) {
 378                                 pr_err("%s() returned %d, expecting %u for "
 379                                                 "S_ISBLK\n", __func__, ret,
 380                                                 cmd->data_length);
 381                                 return (ret < 0 ? ret : -EINVAL);
 382                         }
 383                 } else {
 384                         if (ret < 0) {
 385                                 pr_err("%s() returned %d for non S_ISBLK\n",
 386                                                 __func__, ret);
 387                                 return ret;
 388                         }
 389                 }
 390         }
 391         return 1;
 392 }
 393
 394 static sense_reason_t
 395 fd_execute_sync_cache(struct se_cmd *cmd)
 396 {
 397         struct se_device *dev = cmd->se_dev;
 398         struct fd_dev *fd_dev = FD_DEV(dev);
 399         int immed = (cmd->t_task_cdb[1] & 0x2);
 400         loff_t start, end;
 401         int ret;
 402
 403         /*
 404          * If the Immediate bit is set, queue up the GOOD response
 405          * for this SYNCHRONIZE_CACHE op
 406          */
 407         if (immed)
 408                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 409
 410         /*
 411          * Determine if we will be flushing the entire device.
 412          */
 413         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 414                 start = 0;
 415                 end = LLONG_MAX;
 416         } else {
 417                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 418                 if (cmd->data_length)
 419                         end = start + cmd->data_length - 1;
 420                 else
 421                         end = LLONG_MAX;
 422         }
 423
 424         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 425         if (ret != 0)
 426                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 427
 428         if (immed)
 429                 return 0;
 430
 431         if (ret)
 432                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 433         else
 434                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 435
 436         return 0;
 437 }
 438
 439 static unsigned char *
 440 fd_setup_write_same_buf(struct se_cmd *cmd, struct scatterlist *sg,
 441                     unsigned int len)
 442 {
 443         struct se_device *se_dev = cmd->se_dev;
 444         unsigned int block_size = se_dev->dev_attrib.block_size;
 445         unsigned int i = 0, end;
 446         unsigned char *buf, *p, *kmap_buf;
 447
 448         buf = kzalloc(min_t(unsigned int, len, PAGE_SIZE), GFP_KERNEL);
 449         if (!buf) {
 450                 pr_err("Unable to allocate fd_execute_write_same buf\n");
 451                 return NULL;
 452         }
 453
 454         kmap_buf = kmap(sg_page(sg)) + sg->offset;
 455         if (!kmap_buf) {
 456                 pr_err("kmap() failed in fd_setup_write_same\n");
 457                 kfree(buf);
 458                 return NULL;
 459         }
 460         /*
 461          * Fill local *buf to contain multiple WRITE_SAME blocks up to
 462          * min(len, PAGE_SIZE)
 463          */
 464         p = buf;
 465         end = min_t(unsigned int, len, PAGE_SIZE);
 466
 467         while (i < end) {
 468                 memcpy(p, kmap_buf, block_size);
 469
 470                 i += block_size;
 471                 p += block_size;
 472         }
 473         kunmap(sg_page(sg));
 474
 475         return buf;
 476 }
 477
 478 static sense_reason_t
 479 fd_execute_write_same(struct se_cmd *cmd)
 480 {
 481         struct se_device *se_dev = cmd->se_dev;
 482         struct fd_dev *fd_dev = FD_DEV(se_dev);
 483         struct file *f = fd_dev->fd_file;
 484         struct scatterlist *sg;
 485         struct iovec *iov;
 486         mm_segment_t old_fs;
 487         sector_t nolb = sbc_get_write_same_sectors(cmd);
 488         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 489         unsigned int len, len_tmp, iov_num;
 490         int i, rc;
 491         unsigned char *buf;
 492
 493         if (!nolb) {
 494                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 495                 return 0;
 496         }
 497         sg = &cmd->t_data_sg[0];
 498
 499         if (cmd->t_data_nents > 1 ||
 500             sg->length != cmd->se_dev->dev_attrib.block_size) {
 501                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 502                         " block_size: %u\n", cmd->t_data_nents, sg->length,
 503                         cmd->se_dev->dev_attrib.block_size);
 504                 return TCM_INVALID_CDB_FIELD;
 505         }
 506
 507         len = len_tmp = nolb * se_dev->dev_attrib.block_size;
 508         iov_num = DIV_ROUND_UP(len, PAGE_SIZE);
 509
 510         buf = fd_setup_write_same_buf(cmd, sg, len);
 511         if (!buf)
 512                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 513
 514         iov = vzalloc(sizeof(struct iovec) * iov_num);
 515         if (!iov) {
 516                 pr_err("Unable to allocate fd_execute_write_same iovecs\n");
 517                 kfree(buf);
 518                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 519         }
 520         /*
 521          * Map the single fabric received scatterlist block now populated
 522          * in *buf into each iovec for I/O submission.
 523          */
 524         for (i = 0; i < iov_num; i++) {
 525                 iov[i].iov_base = buf;
 526                 iov[i].iov_len = min_t(unsigned int, len_tmp, PAGE_SIZE);
 527                 len_tmp -= iov[i].iov_len;
 528         }
 529
 530         old_fs = get_fs();
 531         set_fs(get_ds());
 532         rc = vfs_writev(f, &iov[0], iov_num, &pos);
 533         set_fs(old_fs);
 534
 535         vfree(iov);
 536         kfree(buf);
 537
 538         if (rc < 0 || rc != len) {
 539                 pr_err("vfs_writev() returned %d for write same\n", rc);
 540                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 541         }
 542
 543         target_complete_cmd(cmd, SAM_STAT_GOOD);
 544         return 0;
 545 }
 546
 547 static sense_reason_t
 548 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 549 {
 550         struct file *file = priv;
 551         struct inode *inode = file->f_mapping->host;
 552         int ret;
 553
 554         if (S_ISBLK(inode->i_mode)) {
 555                 /* The backend is block device, use discard */
 556                 struct block_device *bdev = inode->i_bdev;
 557
 558                 ret = blkdev_issue_discard(bdev, lba,
 559                                 nolb, GFP_KERNEL, 0);
 560                 if (ret < 0) {
 561                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 562                                 ret);
 563                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 564                 }
 565         } else {
 566                 /* The backend is normal file, use fallocate */
 567                 struct se_device *se_dev = cmd->se_dev;
 568                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 569                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 570                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 571
 572                 if (!file->f_op->fallocate)
 573                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 574
 575                 ret = file->f_op->fallocate(file, mode, pos, len);
 576                 if (ret < 0) {
 577                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 578                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 579                 }
 580         }
 581
 582         return 0;
 583 }
 584
 585 static sense_reason_t
 586 fd_execute_write_same_unmap(struct se_cmd *cmd)
 587 {
 588         struct se_device *se_dev = cmd->se_dev;
 589         struct fd_dev *fd_dev = FD_DEV(se_dev);
 590         struct file *file = fd_dev->fd_file;
 591         sector_t lba = cmd->t_task_lba;
 592         sector_t nolb = sbc_get_write_same_sectors(cmd);
 593         int ret;
 594
 595         if (!nolb) {
 596                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 597                 return 0;
 598         }
 599
 600         ret = fd_do_unmap(cmd, file, lba, nolb);
 601         if (ret)
 602                 return ret;
 603
 604         target_complete_cmd(cmd, GOOD);
 605         return 0;
 606 }
 607
 608 static sense_reason_t
 609 fd_execute_unmap(struct se_cmd *cmd)
 610 {
 611         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 612
 613         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 614 }
 615
 616 static sense_reason_t
 617 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 618               enum dma_data_direction data_direction)
 619 {
 620         struct se_device *dev = cmd->se_dev;
 621         struct fd_prot fd_prot;
 622         sense_reason_t rc;
 623         int ret = 0;
 624         /*
 625          * We are currently limited by the number of iovecs (2048) per
 626          * single vfs_[writev,readv] call.
 627          */
 628         if (cmd->data_length > FD_MAX_BYTES) {
 629                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 630                        "FD_MAX_BYTES: %u iovec count limitiation\n",
 631                         cmd->data_length, FD_MAX_BYTES);
 632                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 633         }
 634         /*
 635          * Call vectorized fileio functions to map struct scatterlist
 636          * physical memory addresses to struct iovec virtual memory.
 637          */
 638         if (data_direction == DMA_FROM_DEVICE) {
 639                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 640
 641                 if (cmd->prot_type) {
 642                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 643                         if (ret < 0)
 644                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 645                 }
 646
 647                 ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
 648
 649                 if (ret > 0 && cmd->prot_type) {
 650                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 651
 652                         rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
 653                                                  0, fd_prot.prot_sg, 0);
 654                         if (rc) {
 655                                 kfree(fd_prot.prot_sg);
 656                                 vfree(fd_prot.prot_buf);
 657                                 return rc;
 658                         }
 659                         kfree(fd_prot.prot_sg);
 660                         vfree(fd_prot.prot_buf);
 661                 }
 662         } else {
 663                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 664
 665                 if (cmd->prot_type) {
 666                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 667
 668                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 669                         if (ret < 0)
 670                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 671
 672                         rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
 673                                                   0, fd_prot.prot_sg, 0);
 674                         if (rc) {
 675                                 kfree(fd_prot.prot_sg);
 676                                 vfree(fd_prot.prot_buf);
 677                                 return rc;
 678                         }
 679                 }
 680
 681                 ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
 682                 /*
 683                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 684                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 685                  * Allow this to happen independent of WCE=0 setting.
 686                  */
 687                 if (ret > 0 &&
 688                     dev->dev_attrib.emulate_fua_write > 0 &&
 689                     (cmd->se_cmd_flags & SCF_FUA)) {
 690                         struct fd_dev *fd_dev = FD_DEV(dev);
 691                         loff_t start = cmd->t_task_lba *
 692                                 dev->dev_attrib.block_size;
 693                         loff_t end;
 694
 695                         if (cmd->data_length)
 696                                 end = start + cmd->data_length - 1;
 697                         else
 698                                 end = LLONG_MAX;
 699
 700                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 701                 }
 702
 703                 if (ret > 0 && cmd->prot_type) {
 704                         ret = fd_do_prot_rw(cmd, &fd_prot, true);
 705                         if (ret < 0)
 706                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 707                 }
 708         }
 709
 710         if (ret < 0) {
 711                 kfree(fd_prot.prot_sg);
 712                 vfree(fd_prot.prot_buf);
 713                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 714         }
 715
 716         if (ret)
 717                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 718         return 0;
 719 }
 720
 721 enum {
 722         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 723 };
 724
 725 static match_table_t tokens = {
 726         {Opt_fd_dev_name, "fd_dev_name=%s"},
 727         {Opt_fd_dev_size, "fd_dev_size=%s"},
 728         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 729         {Opt_err, NULL}
 730 };
 731
 732 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 733                 const char *page, ssize_t count)
 734 {
 735         struct fd_dev *fd_dev = FD_DEV(dev);
 736         char *orig, *ptr, *arg_p, *opts;
 737         substring_t args[MAX_OPT_ARGS];
 738         int ret = 0, arg, token;
 739
 740         opts = kstrdup(page, GFP_KERNEL);
 741         if (!opts)
 742                 return -ENOMEM;
 743
 744         orig = opts;
 745
 746         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 747                 if (!*ptr)
 748                         continue;
 749
 750                 token = match_token(ptr, tokens, args);
 751                 switch (token) {
 752                 case Opt_fd_dev_name:
 753                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 754                                 FD_MAX_DEV_NAME) == 0) {
 755                                 ret = -EINVAL;
 756                                 break;
 757                         }
 758                         pr_debug("FILEIO: Referencing Path: %s\n",
 759                                         fd_dev->fd_dev_name);
 760                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 761                         break;
 762                 case Opt_fd_dev_size:
 763                         arg_p = match_strdup(&args[0]);
 764                         if (!arg_p) {
 765                                 ret = -ENOMEM;
 766                                 break;
 767                         }
 768                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 769                         kfree(arg_p);
 770                         if (ret < 0) {
 771                                 pr_err("kstrtoull() failed for"
 772                                                 " fd_dev_size=\n");
 773                                 goto out;
 774                         }
 775                         pr_debug("FILEIO: Referencing Size: %llu"
 776                                         " bytes\n", fd_dev->fd_dev_size);
 777                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 778                         break;
 779                 case Opt_fd_buffered_io:
 780                         ret = match_int(args, &arg);
 781                         if (ret)
 782                                 goto out;
 783                         if (arg != 1) {
 784                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 785                                 ret = -EINVAL;
 786                                 goto out;
 787                         }
 788
 789                         pr_debug("FILEIO: Using buffered I/O"
 790                                 " operations for struct fd_dev\n");
 791
 792                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 793                         break;
 794                 default:
 795                         break;
 796                 }
 797         }
 798
 799 out:
 800         kfree(orig);
 801         return (!ret) ? count : ret;
 802 }
 803
 804 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 805 {
 806         struct fd_dev *fd_dev = FD_DEV(dev);
 807         ssize_t bl = 0;
 808
 809         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 810         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 811                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 812                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 813                 "Buffered-WCE" : "O_DSYNC");
 814         return bl;
 815 }
 816
 817 static sector_t fd_get_blocks(struct se_device *dev)
 818 {
 819         struct fd_dev *fd_dev = FD_DEV(dev);
 820         struct file *f = fd_dev->fd_file;
 821         struct inode *i = f->f_mapping->host;
 822         unsigned long long dev_size;
 823         /*
 824          * When using a file that references an underlying struct block_device,
 825          * ensure dev_size is always based on the current inode size in order
 826          * to handle underlying block_device resize operations.
 827          */
 828         if (S_ISBLK(i->i_mode))
 829                 dev_size = i_size_read(i);
 830         else
 831                 dev_size = fd_dev->fd_dev_size;
 832
 833         return div_u64(dev_size - dev->dev_attrib.block_size,
 834                        dev->dev_attrib.block_size);
 835 }
 836
 837 static int fd_init_prot(struct se_device *dev)
 838 {
 839         struct fd_dev *fd_dev = FD_DEV(dev);
 840         struct file *prot_file, *file = fd_dev->fd_file;
 841         struct inode *inode;
 842         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 843         char buf[FD_MAX_DEV_PROT_NAME];
 844
 845         if (!file) {
 846                 pr_err("Unable to locate fd_dev->fd_file\n");
 847                 return -ENODEV;
 848         }
 849
 850         inode = file->f_mapping->host;
 851         if (S_ISBLK(inode->i_mode)) {
 852                 pr_err("FILEIO Protection emulation only supported on"
 853                        " !S_ISBLK\n");
 854                 return -ENOSYS;
 855         }
 856
 857         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 858                 flags &= ~O_DSYNC;
 859
 860         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 861                  fd_dev->fd_dev_name);
 862
 863         prot_file = filp_open(buf, flags, 0600);
 864         if (IS_ERR(prot_file)) {
 865                 pr_err("filp_open(%s) failed\n", buf);
 866                 ret = PTR_ERR(prot_file);
 867                 return ret;
 868         }
 869         fd_dev->fd_prot_file = prot_file;
 870
 871         return 0;
 872 }
 873
 874 static int fd_format_prot(struct se_device *dev)
 875 {
 876         struct fd_dev *fd_dev = FD_DEV(dev);
 877         struct file *prot_fd = fd_dev->fd_prot_file;
 878         sector_t prot_length, prot;
 879         unsigned char *buf;
 880         loff_t pos = 0;
 881         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 882         int rc, ret = 0, size, len;
 883
 884         if (!dev->dev_attrib.pi_prot_type) {
 885                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 886                 return -ENODEV;
 887         }
 888         if (!prot_fd) {
 889                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 890                 return -ENODEV;
 891         }
 892
 893         buf = vzalloc(unit_size);
 894         if (!buf) {
 895                 pr_err("Unable to allocate FILEIO prot buf\n");
 896                 return -ENOMEM;
 897         }
 898         prot_length = (dev->transport->get_blocks(dev) + 1) * dev->prot_length;
 899         size = prot_length;
 900
 901         pr_debug("Using FILEIO prot_length: %llu\n",
 902                  (unsigned long long)prot_length);
 903
 904         memset(buf, 0xff, unit_size);
 905         for (prot = 0; prot < prot_length; prot += unit_size) {
 906                 len = min(unit_size, size);
 907                 rc = kernel_write(prot_fd, buf, len, pos);
 908                 if (rc != len) {
 909                         pr_err("vfs_write to prot file failed: %d\n", rc);
 910                         ret = -ENODEV;
 911                         goto out;
 912                 }
 913                 pos += len;
 914                 size -= len;
 915         }
 916
 917 out:
 918         vfree(buf);
 919         return ret;
 920 }
 921
 922 static void fd_free_prot(struct se_device *dev)
 923 {
 924         struct fd_dev *fd_dev = FD_DEV(dev);
 925
 926         if (!fd_dev->fd_prot_file)
 927                 return;
 928
 929         filp_close(fd_dev->fd_prot_file, NULL);
 930         fd_dev->fd_prot_file = NULL;
 931 }
 932
 933 static struct sbc_ops fd_sbc_ops = {
 934         .execute_rw             = fd_execute_rw,
 935         .execute_sync_cache     = fd_execute_sync_cache,
 936         .execute_write_same     = fd_execute_write_same,
 937         .execute_write_same_unmap = fd_execute_write_same_unmap,
 938         .execute_unmap          = fd_execute_unmap,
 939 };
 940
 941 static sense_reason_t
 942 fd_parse_cdb(struct se_cmd *cmd)
 943 {
 944         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 945 }
 946
 947 DEF_TB_DEFAULT_ATTRIBS(fileio);
 948
 949 static struct configfs_attribute *fileio_backend_dev_attrs[] = {
 950         &fileio_dev_attrib_emulate_model_alias.attr,
 951         &fileio_dev_attrib_emulate_dpo.attr,
 952         &fileio_dev_attrib_emulate_fua_write.attr,
 953         &fileio_dev_attrib_emulate_fua_read.attr,
 954         &fileio_dev_attrib_emulate_write_cache.attr,
 955         &fileio_dev_attrib_emulate_ua_intlck_ctrl.attr,
 956         &fileio_dev_attrib_emulate_tas.attr,
 957         &fileio_dev_attrib_emulate_tpu.attr,
 958         &fileio_dev_attrib_emulate_tpws.attr,
 959         &fileio_dev_attrib_emulate_caw.attr,
 960         &fileio_dev_attrib_emulate_3pc.attr,
 961         &fileio_dev_attrib_pi_prot_type.attr,
 962         &fileio_dev_attrib_hw_pi_prot_type.attr,
 963         &fileio_dev_attrib_pi_prot_format.attr,
 964         &fileio_dev_attrib_enforce_pr_isids.attr,
 965         &fileio_dev_attrib_is_nonrot.attr,
 966         &fileio_dev_attrib_emulate_rest_reord.attr,
 967         &fileio_dev_attrib_force_pr_aptpl.attr,
 968         &fileio_dev_attrib_hw_block_size.attr,
 969         &fileio_dev_attrib_block_size.attr,
 970         &fileio_dev_attrib_hw_max_sectors.attr,
 971         &fileio_dev_attrib_optimal_sectors.attr,
 972         &fileio_dev_attrib_hw_queue_depth.attr,
 973         &fileio_dev_attrib_queue_depth.attr,
 974         &fileio_dev_attrib_max_unmap_lba_count.attr,
 975         &fileio_dev_attrib_max_unmap_block_desc_count.attr,
 976         &fileio_dev_attrib_unmap_granularity.attr,
 977         &fileio_dev_attrib_unmap_granularity_alignment.attr,
 978         &fileio_dev_attrib_max_write_same_len.attr,
 979         NULL,
 980 };
 981
 982 static struct se_subsystem_api fileio_template = {
 983         .name                   = "fileio",
 984         .inquiry_prod           = "FILEIO",
 985         .inquiry_rev            = FD_VERSION,
 986         .owner                  = THIS_MODULE,
 987         .transport_type         = TRANSPORT_PLUGIN_VHBA_PDEV,
 988         .attach_hba             = fd_attach_hba,
 989         .detach_hba             = fd_detach_hba,
 990         .alloc_device           = fd_alloc_device,
 991         .configure_device       = fd_configure_device,
 992         .free_device            = fd_free_device,
 993         .parse_cdb              = fd_parse_cdb,
 994         .set_configfs_dev_params = fd_set_configfs_dev_params,
 995         .show_configfs_dev_params = fd_show_configfs_dev_params,
 996         .get_device_type        = sbc_get_device_type,
 997         .get_blocks             = fd_get_blocks,
 998         .init_prot              = fd_init_prot,
 999         .format_prot            = fd_format_prot,
1000         .free_prot              = fd_free_prot,
1001 };
1002
1003 static int __init fileio_module_init(void)
1004 {
1005         struct target_backend_cits *tbc = &fileio_template.tb_cits;
1006
1007         target_core_setup_sub_cits(&fileio_template);
1008         tbc->tb_dev_attrib_cit.ct_attrs = fileio_backend_dev_attrs;
1009
1010         return transport_subsystem_register(&fileio_template);
1011 }
1012
1013 static void __exit fileio_module_exit(void)
1014 {
1015         transport_subsystem_release(&fileio_template);
1016 }
1017
1018 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
1019 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1020 MODULE_LICENSE("GPL");
1021
1022 module_init(fileio_module_init);
1023 module_exit(fileio_module_exit);