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         if (cmd->prot_op) {
 498                 pr_err("WRITE_SAME: Protection information with FILEIO"
 499                        " backends not supported\n");
 500                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 501         }
 502         sg = &cmd->t_data_sg[0];
 503
 504         if (cmd->t_data_nents > 1 ||
 505             sg->length != cmd->se_dev->dev_attrib.block_size) {
 506                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 507                         " block_size: %u\n", cmd->t_data_nents, sg->length,
 508                         cmd->se_dev->dev_attrib.block_size);
 509                 return TCM_INVALID_CDB_FIELD;
 510         }
 511
 512         len = len_tmp = nolb * se_dev->dev_attrib.block_size;
 513         iov_num = DIV_ROUND_UP(len, PAGE_SIZE);
 514
 515         buf = fd_setup_write_same_buf(cmd, sg, len);
 516         if (!buf)
 517                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 518
 519         iov = vzalloc(sizeof(struct iovec) * iov_num);
 520         if (!iov) {
 521                 pr_err("Unable to allocate fd_execute_write_same iovecs\n");
 522                 kfree(buf);
 523                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 524         }
 525         /*
 526          * Map the single fabric received scatterlist block now populated
 527          * in *buf into each iovec for I/O submission.
 528          */
 529         for (i = 0; i < iov_num; i++) {
 530                 iov[i].iov_base = buf;
 531                 iov[i].iov_len = min_t(unsigned int, len_tmp, PAGE_SIZE);
 532                 len_tmp -= iov[i].iov_len;
 533         }
 534
 535         old_fs = get_fs();
 536         set_fs(get_ds());
 537         rc = vfs_writev(f, &iov[0], iov_num, &pos);
 538         set_fs(old_fs);
 539
 540         vfree(iov);
 541         kfree(buf);
 542
 543         if (rc < 0 || rc != len) {
 544                 pr_err("vfs_writev() returned %d for write same\n", rc);
 545                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 546         }
 547
 548         target_complete_cmd(cmd, SAM_STAT_GOOD);
 549         return 0;
 550 }
 551
 552 static sense_reason_t
 553 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 554 {
 555         struct file *file = priv;
 556         struct inode *inode = file->f_mapping->host;
 557         int ret;
 558
 559         if (S_ISBLK(inode->i_mode)) {
 560                 /* The backend is block device, use discard */
 561                 struct block_device *bdev = inode->i_bdev;
 562
 563                 ret = blkdev_issue_discard(bdev, lba,
 564                                 nolb, GFP_KERNEL, 0);
 565                 if (ret < 0) {
 566                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 567                                 ret);
 568                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 569                 }
 570         } else {
 571                 /* The backend is normal file, use fallocate */
 572                 struct se_device *se_dev = cmd->se_dev;
 573                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 574                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 575                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 576
 577                 if (!file->f_op->fallocate)
 578                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 579
 580                 ret = file->f_op->fallocate(file, mode, pos, len);
 581                 if (ret < 0) {
 582                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 583                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 584                 }
 585         }
 586
 587         return 0;
 588 }
 589
 590 static sense_reason_t
 591 fd_execute_write_same_unmap(struct se_cmd *cmd)
 592 {
 593         struct se_device *se_dev = cmd->se_dev;
 594         struct fd_dev *fd_dev = FD_DEV(se_dev);
 595         struct file *file = fd_dev->fd_file;
 596         sector_t lba = cmd->t_task_lba;
 597         sector_t nolb = sbc_get_write_same_sectors(cmd);
 598         int ret;
 599
 600         if (!nolb) {
 601                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 602                 return 0;
 603         }
 604
 605         ret = fd_do_unmap(cmd, file, lba, nolb);
 606         if (ret)
 607                 return ret;
 608
 609         target_complete_cmd(cmd, GOOD);
 610         return 0;
 611 }
 612
 613 static sense_reason_t
 614 fd_execute_unmap(struct se_cmd *cmd)
 615 {
 616         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 617
 618         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 619 }
 620
 621 static sense_reason_t
 622 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 623               enum dma_data_direction data_direction)
 624 {
 625         struct se_device *dev = cmd->se_dev;
 626         struct fd_prot fd_prot;
 627         sense_reason_t rc;
 628         int ret = 0;
 629         /*
 630          * We are currently limited by the number of iovecs (2048) per
 631          * single vfs_[writev,readv] call.
 632          */
 633         if (cmd->data_length > FD_MAX_BYTES) {
 634                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 635                        "FD_MAX_BYTES: %u iovec count limitiation\n",
 636                         cmd->data_length, FD_MAX_BYTES);
 637                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 638         }
 639         /*
 640          * Call vectorized fileio functions to map struct scatterlist
 641          * physical memory addresses to struct iovec virtual memory.
 642          */
 643         if (data_direction == DMA_FROM_DEVICE) {
 644                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 645
 646                 if (cmd->prot_type) {
 647                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 648                         if (ret < 0)
 649                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 650                 }
 651
 652                 ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
 653
 654                 if (ret > 0 && cmd->prot_type) {
 655                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 656
 657                         rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
 658                                                  0, fd_prot.prot_sg, 0);
 659                         if (rc) {
 660                                 kfree(fd_prot.prot_sg);
 661                                 vfree(fd_prot.prot_buf);
 662                                 return rc;
 663                         }
 664                         kfree(fd_prot.prot_sg);
 665                         vfree(fd_prot.prot_buf);
 666                 }
 667         } else {
 668                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 669
 670                 if (cmd->prot_type) {
 671                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 672
 673                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 674                         if (ret < 0)
 675                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 676
 677                         rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
 678                                                   0, fd_prot.prot_sg, 0);
 679                         if (rc) {
 680                                 kfree(fd_prot.prot_sg);
 681                                 vfree(fd_prot.prot_buf);
 682                                 return rc;
 683                         }
 684                 }
 685
 686                 ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
 687                 /*
 688                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 689                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 690                  * Allow this to happen independent of WCE=0 setting.
 691                  */
 692                 if (ret > 0 &&
 693                     dev->dev_attrib.emulate_fua_write > 0 &&
 694                     (cmd->se_cmd_flags & SCF_FUA)) {
 695                         struct fd_dev *fd_dev = FD_DEV(dev);
 696                         loff_t start = cmd->t_task_lba *
 697                                 dev->dev_attrib.block_size;
 698                         loff_t end;
 699
 700                         if (cmd->data_length)
 701                                 end = start + cmd->data_length - 1;
 702                         else
 703                                 end = LLONG_MAX;
 704
 705                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 706                 }
 707
 708                 if (ret > 0 && cmd->prot_type) {
 709                         ret = fd_do_prot_rw(cmd, &fd_prot, true);
 710                         if (ret < 0)
 711                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 712                 }
 713         }
 714
 715         if (ret < 0) {
 716                 kfree(fd_prot.prot_sg);
 717                 vfree(fd_prot.prot_buf);
 718                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 719         }
 720
 721         if (ret)
 722                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 723         return 0;
 724 }
 725
 726 enum {
 727         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 728 };
 729
 730 static match_table_t tokens = {
 731         {Opt_fd_dev_name, "fd_dev_name=%s"},
 732         {Opt_fd_dev_size, "fd_dev_size=%s"},
 733         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 734         {Opt_err, NULL}
 735 };
 736
 737 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 738                 const char *page, ssize_t count)
 739 {
 740         struct fd_dev *fd_dev = FD_DEV(dev);
 741         char *orig, *ptr, *arg_p, *opts;
 742         substring_t args[MAX_OPT_ARGS];
 743         int ret = 0, arg, token;
 744
 745         opts = kstrdup(page, GFP_KERNEL);
 746         if (!opts)
 747                 return -ENOMEM;
 748
 749         orig = opts;
 750
 751         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 752                 if (!*ptr)
 753                         continue;
 754
 755                 token = match_token(ptr, tokens, args);
 756                 switch (token) {
 757                 case Opt_fd_dev_name:
 758                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 759                                 FD_MAX_DEV_NAME) == 0) {
 760                                 ret = -EINVAL;
 761                                 break;
 762                         }
 763                         pr_debug("FILEIO: Referencing Path: %s\n",
 764                                         fd_dev->fd_dev_name);
 765                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 766                         break;
 767                 case Opt_fd_dev_size:
 768                         arg_p = match_strdup(&args[0]);
 769                         if (!arg_p) {
 770                                 ret = -ENOMEM;
 771                                 break;
 772                         }
 773                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 774                         kfree(arg_p);
 775                         if (ret < 0) {
 776                                 pr_err("kstrtoull() failed for"
 777                                                 " fd_dev_size=\n");
 778                                 goto out;
 779                         }
 780                         pr_debug("FILEIO: Referencing Size: %llu"
 781                                         " bytes\n", fd_dev->fd_dev_size);
 782                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 783                         break;
 784                 case Opt_fd_buffered_io:
 785                         ret = match_int(args, &arg);
 786                         if (ret)
 787                                 goto out;
 788                         if (arg != 1) {
 789                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 790                                 ret = -EINVAL;
 791                                 goto out;
 792                         }
 793
 794                         pr_debug("FILEIO: Using buffered I/O"
 795                                 " operations for struct fd_dev\n");
 796
 797                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 798                         break;
 799                 default:
 800                         break;
 801                 }
 802         }
 803
 804 out:
 805         kfree(orig);
 806         return (!ret) ? count : ret;
 807 }
 808
 809 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 810 {
 811         struct fd_dev *fd_dev = FD_DEV(dev);
 812         ssize_t bl = 0;
 813
 814         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 815         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 816                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 817                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 818                 "Buffered-WCE" : "O_DSYNC");
 819         return bl;
 820 }
 821
 822 static sector_t fd_get_blocks(struct se_device *dev)
 823 {
 824         struct fd_dev *fd_dev = FD_DEV(dev);
 825         struct file *f = fd_dev->fd_file;
 826         struct inode *i = f->f_mapping->host;
 827         unsigned long long dev_size;
 828         /*
 829          * When using a file that references an underlying struct block_device,
 830          * ensure dev_size is always based on the current inode size in order
 831          * to handle underlying block_device resize operations.
 832          */
 833         if (S_ISBLK(i->i_mode))
 834                 dev_size = i_size_read(i);
 835         else
 836                 dev_size = fd_dev->fd_dev_size;
 837
 838         return div_u64(dev_size - dev->dev_attrib.block_size,
 839                        dev->dev_attrib.block_size);
 840 }
 841
 842 static int fd_init_prot(struct se_device *dev)
 843 {
 844         struct fd_dev *fd_dev = FD_DEV(dev);
 845         struct file *prot_file, *file = fd_dev->fd_file;
 846         struct inode *inode;
 847         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 848         char buf[FD_MAX_DEV_PROT_NAME];
 849
 850         if (!file) {
 851                 pr_err("Unable to locate fd_dev->fd_file\n");
 852                 return -ENODEV;
 853         }
 854
 855         inode = file->f_mapping->host;
 856         if (S_ISBLK(inode->i_mode)) {
 857                 pr_err("FILEIO Protection emulation only supported on"
 858                        " !S_ISBLK\n");
 859                 return -ENOSYS;
 860         }
 861
 862         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 863                 flags &= ~O_DSYNC;
 864
 865         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 866                  fd_dev->fd_dev_name);
 867
 868         prot_file = filp_open(buf, flags, 0600);
 869         if (IS_ERR(prot_file)) {
 870                 pr_err("filp_open(%s) failed\n", buf);
 871                 ret = PTR_ERR(prot_file);
 872                 return ret;
 873         }
 874         fd_dev->fd_prot_file = prot_file;
 875
 876         return 0;
 877 }
 878
 879 static int fd_format_prot(struct se_device *dev)
 880 {
 881         struct fd_dev *fd_dev = FD_DEV(dev);
 882         struct file *prot_fd = fd_dev->fd_prot_file;
 883         sector_t prot_length, prot;
 884         unsigned char *buf;
 885         loff_t pos = 0;
 886         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 887         int rc, ret = 0, size, len;
 888
 889         if (!dev->dev_attrib.pi_prot_type) {
 890                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 891                 return -ENODEV;
 892         }
 893         if (!prot_fd) {
 894                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 895                 return -ENODEV;
 896         }
 897
 898         buf = vzalloc(unit_size);
 899         if (!buf) {
 900                 pr_err("Unable to allocate FILEIO prot buf\n");
 901                 return -ENOMEM;
 902         }
 903         prot_length = (dev->transport->get_blocks(dev) + 1) * dev->prot_length;
 904         size = prot_length;
 905
 906         pr_debug("Using FILEIO prot_length: %llu\n",
 907                  (unsigned long long)prot_length);
 908
 909         memset(buf, 0xff, unit_size);
 910         for (prot = 0; prot < prot_length; prot += unit_size) {
 911                 len = min(unit_size, size);
 912                 rc = kernel_write(prot_fd, buf, len, pos);
 913                 if (rc != len) {
 914                         pr_err("vfs_write to prot file failed: %d\n", rc);
 915                         ret = -ENODEV;
 916                         goto out;
 917                 }
 918                 pos += len;
 919                 size -= len;
 920         }
 921
 922 out:
 923         vfree(buf);
 924         return ret;
 925 }
 926
 927 static void fd_free_prot(struct se_device *dev)
 928 {
 929         struct fd_dev *fd_dev = FD_DEV(dev);
 930
 931         if (!fd_dev->fd_prot_file)
 932                 return;
 933
 934         filp_close(fd_dev->fd_prot_file, NULL);
 935         fd_dev->fd_prot_file = NULL;
 936 }
 937
 938 static struct sbc_ops fd_sbc_ops = {
 939         .execute_rw             = fd_execute_rw,
 940         .execute_sync_cache     = fd_execute_sync_cache,
 941         .execute_write_same     = fd_execute_write_same,
 942         .execute_write_same_unmap = fd_execute_write_same_unmap,
 943         .execute_unmap          = fd_execute_unmap,
 944 };
 945
 946 static sense_reason_t
 947 fd_parse_cdb(struct se_cmd *cmd)
 948 {
 949         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 950 }
 951
 952 DEF_TB_DEFAULT_ATTRIBS(fileio);
 953
 954 static struct configfs_attribute *fileio_backend_dev_attrs[] = {
 955         &fileio_dev_attrib_emulate_model_alias.attr,
 956         &fileio_dev_attrib_emulate_dpo.attr,
 957         &fileio_dev_attrib_emulate_fua_write.attr,
 958         &fileio_dev_attrib_emulate_fua_read.attr,
 959         &fileio_dev_attrib_emulate_write_cache.attr,
 960         &fileio_dev_attrib_emulate_ua_intlck_ctrl.attr,
 961         &fileio_dev_attrib_emulate_tas.attr,
 962         &fileio_dev_attrib_emulate_tpu.attr,
 963         &fileio_dev_attrib_emulate_tpws.attr,
 964         &fileio_dev_attrib_emulate_caw.attr,
 965         &fileio_dev_attrib_emulate_3pc.attr,
 966         &fileio_dev_attrib_pi_prot_type.attr,
 967         &fileio_dev_attrib_hw_pi_prot_type.attr,
 968         &fileio_dev_attrib_pi_prot_format.attr,
 969         &fileio_dev_attrib_enforce_pr_isids.attr,
 970         &fileio_dev_attrib_is_nonrot.attr,
 971         &fileio_dev_attrib_emulate_rest_reord.attr,
 972         &fileio_dev_attrib_force_pr_aptpl.attr,
 973         &fileio_dev_attrib_hw_block_size.attr,
 974         &fileio_dev_attrib_block_size.attr,
 975         &fileio_dev_attrib_hw_max_sectors.attr,
 976         &fileio_dev_attrib_optimal_sectors.attr,
 977         &fileio_dev_attrib_hw_queue_depth.attr,
 978         &fileio_dev_attrib_queue_depth.attr,
 979         &fileio_dev_attrib_max_unmap_lba_count.attr,
 980         &fileio_dev_attrib_max_unmap_block_desc_count.attr,
 981         &fileio_dev_attrib_unmap_granularity.attr,
 982         &fileio_dev_attrib_unmap_granularity_alignment.attr,
 983         &fileio_dev_attrib_max_write_same_len.attr,
 984         NULL,
 985 };
 986
 987 static struct se_subsystem_api fileio_template = {
 988         .name                   = "fileio",
 989         .inquiry_prod           = "FILEIO",
 990         .inquiry_rev            = FD_VERSION,
 991         .owner                  = THIS_MODULE,
 992         .transport_type         = TRANSPORT_PLUGIN_VHBA_PDEV,
 993         .attach_hba             = fd_attach_hba,
 994         .detach_hba             = fd_detach_hba,
 995         .alloc_device           = fd_alloc_device,
 996         .configure_device       = fd_configure_device,
 997         .free_device            = fd_free_device,
 998         .parse_cdb              = fd_parse_cdb,
 999         .set_configfs_dev_params = fd_set_configfs_dev_params,
1000         .show_configfs_dev_params = fd_show_configfs_dev_params,
1001         .get_device_type        = sbc_get_device_type,
1002         .get_blocks             = fd_get_blocks,
1003         .init_prot              = fd_init_prot,
1004         .format_prot            = fd_format_prot,
1005         .free_prot              = fd_free_prot,
1006 };
1007
1008 static int __init fileio_module_init(void)
1009 {
1010         struct target_backend_cits *tbc = &fileio_template.tb_cits;
1011
1012         target_core_setup_sub_cits(&fileio_template);
1013         tbc->tb_dev_attrib_cit.ct_attrs = fileio_backend_dev_attrs;
1014
1015         return transport_subsystem_register(&fileio_template);
1016 }
1017
1018 static void __exit fileio_module_exit(void)
1019 {
1020         transport_subsystem_release(&fileio_template);
1021 }
1022
1023 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
1024 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1025 MODULE_LICENSE("GPL");
1026
1027 module_init(fileio_module_init);
1028 module_exit(fileio_module_exit);