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