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_proto.h>
  35 #include <asm/unaligned.h>
  36
  37 #include <target/target_core_base.h>
  38 #include <target/target_core_backend.h>
  39 #include <target/target_core_backend_configfs.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         loff_t pos = (cmd->t_task_lba * se_dev->prot_length);
 267         unsigned char *buf;
 268         u32 prot_size;
 269         int rc, ret = 1;
 270
 271         prot_size = (cmd->data_length / se_dev->dev_attrib.block_size) *
 272                      se_dev->prot_length;
 273
 274         if (!is_write) {
 275                 fd_prot->prot_buf = kzalloc(prot_size, GFP_KERNEL);
 276                 if (!fd_prot->prot_buf) {
 277                         pr_err("Unable to allocate fd_prot->prot_buf\n");
 278                         return -ENOMEM;
 279                 }
 280                 buf = fd_prot->prot_buf;
 281
 282                 fd_prot->prot_sg_nents = 1;
 283                 fd_prot->prot_sg = kzalloc(sizeof(struct scatterlist),
 284                                            GFP_KERNEL);
 285                 if (!fd_prot->prot_sg) {
 286                         pr_err("Unable to allocate fd_prot->prot_sg\n");
 287                         kfree(fd_prot->prot_buf);
 288                         return -ENOMEM;
 289                 }
 290                 sg_init_table(fd_prot->prot_sg, fd_prot->prot_sg_nents);
 291                 sg_set_buf(fd_prot->prot_sg, buf, prot_size);
 292         }
 293
 294         if (is_write) {
 295                 rc = kernel_write(prot_fd, fd_prot->prot_buf, prot_size, pos);
 296                 if (rc < 0 || prot_size != rc) {
 297                         pr_err("kernel_write() for fd_do_prot_rw failed:"
 298                                " %d\n", rc);
 299                         ret = -EINVAL;
 300                 }
 301         } else {
 302                 rc = kernel_read(prot_fd, pos, fd_prot->prot_buf, prot_size);
 303                 if (rc < 0) {
 304                         pr_err("kernel_read() for fd_do_prot_rw failed:"
 305                                " %d\n", rc);
 306                         ret = -EINVAL;
 307                 }
 308         }
 309
 310         if (is_write || ret < 0) {
 311                 kfree(fd_prot->prot_sg);
 312                 kfree(fd_prot->prot_buf);
 313         }
 314
 315         return ret;
 316 }
 317
 318 static int fd_do_rw(struct se_cmd *cmd, struct scatterlist *sgl,
 319                 u32 sgl_nents, int is_write)
 320 {
 321         struct se_device *se_dev = cmd->se_dev;
 322         struct fd_dev *dev = FD_DEV(se_dev);
 323         struct file *fd = dev->fd_file;
 324         struct scatterlist *sg;
 325         struct iov_iter iter;
 326         struct bio_vec *bvec;
 327         ssize_t len = 0;
 328         loff_t pos = (cmd->t_task_lba * se_dev->dev_attrib.block_size);
 329         int ret = 0, i;
 330
 331         bvec = kcalloc(sgl_nents, sizeof(struct bio_vec), GFP_KERNEL);
 332         if (!bvec) {
 333                 pr_err("Unable to allocate fd_do_readv iov[]\n");
 334                 return -ENOMEM;
 335         }
 336
 337         for_each_sg(sgl, sg, sgl_nents, i) {
 338                 bvec[i].bv_page = sg_page(sg);
 339                 bvec[i].bv_len = sg->length;
 340                 bvec[i].bv_offset = sg->offset;
 341
 342                 len += sg->length;
 343         }
 344
 345         iov_iter_bvec(&iter, ITER_BVEC, bvec, sgl_nents, len);
 346         if (is_write)
 347                 ret = vfs_iter_write(fd, &iter, &pos);
 348         else
 349                 ret = vfs_iter_read(fd, &iter, &pos);
 350
 351         kfree(bvec);
 352
 353         if (is_write) {
 354                 if (ret < 0 || ret != cmd->data_length) {
 355                         pr_err("%s() write returned %d\n", __func__, ret);
 356                         return (ret < 0 ? ret : -EINVAL);
 357                 }
 358         } else {
 359                 /*
 360                  * Return zeros and GOOD status even if the READ did not return
 361                  * the expected virt_size for struct file w/o a backing struct
 362                  * block_device.
 363                  */
 364                 if (S_ISBLK(file_inode(fd)->i_mode)) {
 365                         if (ret < 0 || ret != cmd->data_length) {
 366                                 pr_err("%s() returned %d, expecting %u for "
 367                                                 "S_ISBLK\n", __func__, ret,
 368                                                 cmd->data_length);
 369                                 return (ret < 0 ? ret : -EINVAL);
 370                         }
 371                 } else {
 372                         if (ret < 0) {
 373                                 pr_err("%s() returned %d for non S_ISBLK\n",
 374                                                 __func__, ret);
 375                                 return ret;
 376                         }
 377                 }
 378         }
 379         return 1;
 380 }
 381
 382 static sense_reason_t
 383 fd_execute_sync_cache(struct se_cmd *cmd)
 384 {
 385         struct se_device *dev = cmd->se_dev;
 386         struct fd_dev *fd_dev = FD_DEV(dev);
 387         int immed = (cmd->t_task_cdb[1] & 0x2);
 388         loff_t start, end;
 389         int ret;
 390
 391         /*
 392          * If the Immediate bit is set, queue up the GOOD response
 393          * for this SYNCHRONIZE_CACHE op
 394          */
 395         if (immed)
 396                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 397
 398         /*
 399          * Determine if we will be flushing the entire device.
 400          */
 401         if (cmd->t_task_lba == 0 && cmd->data_length == 0) {
 402                 start = 0;
 403                 end = LLONG_MAX;
 404         } else {
 405                 start = cmd->t_task_lba * dev->dev_attrib.block_size;
 406                 if (cmd->data_length)
 407                         end = start + cmd->data_length - 1;
 408                 else
 409                         end = LLONG_MAX;
 410         }
 411
 412         ret = vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 413         if (ret != 0)
 414                 pr_err("FILEIO: vfs_fsync_range() failed: %d\n", ret);
 415
 416         if (immed)
 417                 return 0;
 418
 419         if (ret)
 420                 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
 421         else
 422                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 423
 424         return 0;
 425 }
 426
 427 static sense_reason_t
 428 fd_execute_write_same(struct se_cmd *cmd)
 429 {
 430         struct se_device *se_dev = cmd->se_dev;
 431         struct fd_dev *fd_dev = FD_DEV(se_dev);
 432         loff_t pos = cmd->t_task_lba * se_dev->dev_attrib.block_size;
 433         sector_t nolb = sbc_get_write_same_sectors(cmd);
 434         struct iov_iter iter;
 435         struct bio_vec *bvec;
 436         unsigned int len = 0, i;
 437         ssize_t ret;
 438
 439         if (!nolb) {
 440                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 441                 return 0;
 442         }
 443         if (cmd->prot_op) {
 444                 pr_err("WRITE_SAME: Protection information with FILEIO"
 445                        " backends not supported\n");
 446                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 447         }
 448
 449         if (cmd->t_data_nents > 1 ||
 450             cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
 451                 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
 452                         " block_size: %u\n",
 453                         cmd->t_data_nents,
 454                         cmd->t_data_sg[0].length,
 455                         cmd->se_dev->dev_attrib.block_size);
 456                 return TCM_INVALID_CDB_FIELD;
 457         }
 458
 459         bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
 460         if (!bvec)
 461                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 462
 463         for (i = 0; i < nolb; i++) {
 464                 bvec[i].bv_page = sg_page(&cmd->t_data_sg[0]);
 465                 bvec[i].bv_len = cmd->t_data_sg[0].length;
 466                 bvec[i].bv_offset = cmd->t_data_sg[0].offset;
 467
 468                 len += se_dev->dev_attrib.block_size;
 469         }
 470
 471         iov_iter_bvec(&iter, ITER_BVEC, bvec, nolb, len);
 472         ret = vfs_iter_write(fd_dev->fd_file, &iter, &pos);
 473
 474         kfree(bvec);
 475         if (ret < 0 || ret != len) {
 476                 pr_err("vfs_iter_write() returned %zd for write same\n", ret);
 477                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 478         }
 479
 480         target_complete_cmd(cmd, SAM_STAT_GOOD);
 481         return 0;
 482 }
 483
 484 static int
 485 fd_do_prot_fill(struct se_device *se_dev, sector_t lba, sector_t nolb,
 486                 void *buf, size_t bufsize)
 487 {
 488         struct fd_dev *fd_dev = FD_DEV(se_dev);
 489         struct file *prot_fd = fd_dev->fd_prot_file;
 490         sector_t prot_length, prot;
 491         loff_t pos = lba * se_dev->prot_length;
 492
 493         if (!prot_fd) {
 494                 pr_err("Unable to locate fd_dev->fd_prot_file\n");
 495                 return -ENODEV;
 496         }
 497
 498         prot_length = nolb * se_dev->prot_length;
 499
 500         for (prot = 0; prot < prot_length;) {
 501                 sector_t len = min_t(sector_t, bufsize, prot_length - prot);
 502                 ssize_t ret = kernel_write(prot_fd, buf, len, pos + prot);
 503
 504                 if (ret != len) {
 505                         pr_err("vfs_write to prot file failed: %zd\n", ret);
 506                         return ret < 0 ? ret : -ENODEV;
 507                 }
 508                 prot += ret;
 509         }
 510
 511         return 0;
 512 }
 513
 514 static int
 515 fd_do_prot_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
 516 {
 517         void *buf;
 518         int rc;
 519
 520         buf = (void *)__get_free_page(GFP_KERNEL);
 521         if (!buf) {
 522                 pr_err("Unable to allocate FILEIO prot buf\n");
 523                 return -ENOMEM;
 524         }
 525         memset(buf, 0xff, PAGE_SIZE);
 526
 527         rc = fd_do_prot_fill(cmd->se_dev, lba, nolb, buf, PAGE_SIZE);
 528
 529         free_page((unsigned long)buf);
 530
 531         return rc;
 532 }
 533
 534 static sense_reason_t
 535 fd_do_unmap(struct se_cmd *cmd, void *priv, sector_t lba, sector_t nolb)
 536 {
 537         struct file *file = priv;
 538         struct inode *inode = file->f_mapping->host;
 539         int ret;
 540
 541         if (cmd->se_dev->dev_attrib.pi_prot_type) {
 542                 ret = fd_do_prot_unmap(cmd, lba, nolb);
 543                 if (ret)
 544                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 545         }
 546
 547         if (S_ISBLK(inode->i_mode)) {
 548                 /* The backend is block device, use discard */
 549                 struct block_device *bdev = inode->i_bdev;
 550
 551                 ret = blkdev_issue_discard(bdev, lba,
 552                                 nolb, GFP_KERNEL, 0);
 553                 if (ret < 0) {
 554                         pr_warn("FILEIO: blkdev_issue_discard() failed: %d\n",
 555                                 ret);
 556                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 557                 }
 558         } else {
 559                 /* The backend is normal file, use fallocate */
 560                 struct se_device *se_dev = cmd->se_dev;
 561                 loff_t pos = lba * se_dev->dev_attrib.block_size;
 562                 unsigned int len = nolb * se_dev->dev_attrib.block_size;
 563                 int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
 564
 565                 if (!file->f_op->fallocate)
 566                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 567
 568                 ret = file->f_op->fallocate(file, mode, pos, len);
 569                 if (ret < 0) {
 570                         pr_warn("FILEIO: fallocate() failed: %d\n", ret);
 571                         return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 572                 }
 573         }
 574
 575         return 0;
 576 }
 577
 578 static sense_reason_t
 579 fd_execute_write_same_unmap(struct se_cmd *cmd)
 580 {
 581         struct se_device *se_dev = cmd->se_dev;
 582         struct fd_dev *fd_dev = FD_DEV(se_dev);
 583         struct file *file = fd_dev->fd_file;
 584         sector_t lba = cmd->t_task_lba;
 585         sector_t nolb = sbc_get_write_same_sectors(cmd);
 586         sense_reason_t ret;
 587
 588         if (!nolb) {
 589                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 590                 return 0;
 591         }
 592
 593         ret = fd_do_unmap(cmd, file, lba, nolb);
 594         if (ret)
 595                 return ret;
 596
 597         target_complete_cmd(cmd, GOOD);
 598         return 0;
 599 }
 600
 601 static sense_reason_t
 602 fd_execute_unmap(struct se_cmd *cmd)
 603 {
 604         struct file *file = FD_DEV(cmd->se_dev)->fd_file;
 605
 606         return sbc_execute_unmap(cmd, fd_do_unmap, file);
 607 }
 608
 609 static sense_reason_t
 610 fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 611               enum dma_data_direction data_direction)
 612 {
 613         struct se_device *dev = cmd->se_dev;
 614         struct fd_prot fd_prot;
 615         sense_reason_t rc;
 616         int ret = 0;
 617         /*
 618          * We are currently limited by the number of iovecs (2048) per
 619          * single vfs_[writev,readv] call.
 620          */
 621         if (cmd->data_length > FD_MAX_BYTES) {
 622                 pr_err("FILEIO: Not able to process I/O of %u bytes due to"
 623                        "FD_MAX_BYTES: %u iovec count limitiation\n",
 624                         cmd->data_length, FD_MAX_BYTES);
 625                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 626         }
 627         /*
 628          * Call vectorized fileio functions to map struct scatterlist
 629          * physical memory addresses to struct iovec virtual memory.
 630          */
 631         if (data_direction == DMA_FROM_DEVICE) {
 632                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 633
 634                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 635                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 636                         if (ret < 0)
 637                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 638                 }
 639
 640                 ret = fd_do_rw(cmd, sgl, sgl_nents, 0);
 641
 642                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 643                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 644
 645                         rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors,
 646                                                  0, fd_prot.prot_sg, 0);
 647                         if (rc) {
 648                                 kfree(fd_prot.prot_sg);
 649                                 kfree(fd_prot.prot_buf);
 650                                 return rc;
 651                         }
 652                         kfree(fd_prot.prot_sg);
 653                         kfree(fd_prot.prot_buf);
 654                 }
 655         } else {
 656                 memset(&fd_prot, 0, sizeof(struct fd_prot));
 657
 658                 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 659                         u32 sectors = cmd->data_length / dev->dev_attrib.block_size;
 660
 661                         ret = fd_do_prot_rw(cmd, &fd_prot, false);
 662                         if (ret < 0)
 663                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 664
 665                         rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors,
 666                                                   0, fd_prot.prot_sg, 0);
 667                         if (rc) {
 668                                 kfree(fd_prot.prot_sg);
 669                                 kfree(fd_prot.prot_buf);
 670                                 return rc;
 671                         }
 672                 }
 673
 674                 ret = fd_do_rw(cmd, sgl, sgl_nents, 1);
 675                 /*
 676                  * Perform implicit vfs_fsync_range() for fd_do_writev() ops
 677                  * for SCSI WRITEs with Forced Unit Access (FUA) set.
 678                  * Allow this to happen independent of WCE=0 setting.
 679                  */
 680                 if (ret > 0 &&
 681                     dev->dev_attrib.emulate_fua_write > 0 &&
 682                     (cmd->se_cmd_flags & SCF_FUA)) {
 683                         struct fd_dev *fd_dev = FD_DEV(dev);
 684                         loff_t start = cmd->t_task_lba *
 685                                 dev->dev_attrib.block_size;
 686                         loff_t end;
 687
 688                         if (cmd->data_length)
 689                                 end = start + cmd->data_length - 1;
 690                         else
 691                                 end = LLONG_MAX;
 692
 693                         vfs_fsync_range(fd_dev->fd_file, start, end, 1);
 694                 }
 695
 696                 if (ret > 0 && cmd->prot_type && dev->dev_attrib.pi_prot_type) {
 697                         ret = fd_do_prot_rw(cmd, &fd_prot, true);
 698                         if (ret < 0)
 699                                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 700                 }
 701         }
 702
 703         if (ret < 0) {
 704                 kfree(fd_prot.prot_sg);
 705                 kfree(fd_prot.prot_buf);
 706                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 707         }
 708
 709         if (ret)
 710                 target_complete_cmd(cmd, SAM_STAT_GOOD);
 711         return 0;
 712 }
 713
 714 enum {
 715         Opt_fd_dev_name, Opt_fd_dev_size, Opt_fd_buffered_io, Opt_err
 716 };
 717
 718 static match_table_t tokens = {
 719         {Opt_fd_dev_name, "fd_dev_name=%s"},
 720         {Opt_fd_dev_size, "fd_dev_size=%s"},
 721         {Opt_fd_buffered_io, "fd_buffered_io=%d"},
 722         {Opt_err, NULL}
 723 };
 724
 725 static ssize_t fd_set_configfs_dev_params(struct se_device *dev,
 726                 const char *page, ssize_t count)
 727 {
 728         struct fd_dev *fd_dev = FD_DEV(dev);
 729         char *orig, *ptr, *arg_p, *opts;
 730         substring_t args[MAX_OPT_ARGS];
 731         int ret = 0, arg, token;
 732
 733         opts = kstrdup(page, GFP_KERNEL);
 734         if (!opts)
 735                 return -ENOMEM;
 736
 737         orig = opts;
 738
 739         while ((ptr = strsep(&opts, ",\n")) != NULL) {
 740                 if (!*ptr)
 741                         continue;
 742
 743                 token = match_token(ptr, tokens, args);
 744                 switch (token) {
 745                 case Opt_fd_dev_name:
 746                         if (match_strlcpy(fd_dev->fd_dev_name, &args[0],
 747                                 FD_MAX_DEV_NAME) == 0) {
 748                                 ret = -EINVAL;
 749                                 break;
 750                         }
 751                         pr_debug("FILEIO: Referencing Path: %s\n",
 752                                         fd_dev->fd_dev_name);
 753                         fd_dev->fbd_flags |= FBDF_HAS_PATH;
 754                         break;
 755                 case Opt_fd_dev_size:
 756                         arg_p = match_strdup(&args[0]);
 757                         if (!arg_p) {
 758                                 ret = -ENOMEM;
 759                                 break;
 760                         }
 761                         ret = kstrtoull(arg_p, 0, &fd_dev->fd_dev_size);
 762                         kfree(arg_p);
 763                         if (ret < 0) {
 764                                 pr_err("kstrtoull() failed for"
 765                                                 " fd_dev_size=\n");
 766                                 goto out;
 767                         }
 768                         pr_debug("FILEIO: Referencing Size: %llu"
 769                                         " bytes\n", fd_dev->fd_dev_size);
 770                         fd_dev->fbd_flags |= FBDF_HAS_SIZE;
 771                         break;
 772                 case Opt_fd_buffered_io:
 773                         ret = match_int(args, &arg);
 774                         if (ret)
 775                                 goto out;
 776                         if (arg != 1) {
 777                                 pr_err("bogus fd_buffered_io=%d value\n", arg);
 778                                 ret = -EINVAL;
 779                                 goto out;
 780                         }
 781
 782                         pr_debug("FILEIO: Using buffered I/O"
 783                                 " operations for struct fd_dev\n");
 784
 785                         fd_dev->fbd_flags |= FDBD_HAS_BUFFERED_IO_WCE;
 786                         break;
 787                 default:
 788                         break;
 789                 }
 790         }
 791
 792 out:
 793         kfree(orig);
 794         return (!ret) ? count : ret;
 795 }
 796
 797 static ssize_t fd_show_configfs_dev_params(struct se_device *dev, char *b)
 798 {
 799         struct fd_dev *fd_dev = FD_DEV(dev);
 800         ssize_t bl = 0;
 801
 802         bl = sprintf(b + bl, "TCM FILEIO ID: %u", fd_dev->fd_dev_id);
 803         bl += sprintf(b + bl, "        File: %s  Size: %llu  Mode: %s\n",
 804                 fd_dev->fd_dev_name, fd_dev->fd_dev_size,
 805                 (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE) ?
 806                 "Buffered-WCE" : "O_DSYNC");
 807         return bl;
 808 }
 809
 810 static sector_t fd_get_blocks(struct se_device *dev)
 811 {
 812         struct fd_dev *fd_dev = FD_DEV(dev);
 813         struct file *f = fd_dev->fd_file;
 814         struct inode *i = f->f_mapping->host;
 815         unsigned long long dev_size;
 816         /*
 817          * When using a file that references an underlying struct block_device,
 818          * ensure dev_size is always based on the current inode size in order
 819          * to handle underlying block_device resize operations.
 820          */
 821         if (S_ISBLK(i->i_mode))
 822                 dev_size = i_size_read(i);
 823         else
 824                 dev_size = fd_dev->fd_dev_size;
 825
 826         return div_u64(dev_size - dev->dev_attrib.block_size,
 827                        dev->dev_attrib.block_size);
 828 }
 829
 830 static int fd_init_prot(struct se_device *dev)
 831 {
 832         struct fd_dev *fd_dev = FD_DEV(dev);
 833         struct file *prot_file, *file = fd_dev->fd_file;
 834         struct inode *inode;
 835         int ret, flags = O_RDWR | O_CREAT | O_LARGEFILE | O_DSYNC;
 836         char buf[FD_MAX_DEV_PROT_NAME];
 837
 838         if (!file) {
 839                 pr_err("Unable to locate fd_dev->fd_file\n");
 840                 return -ENODEV;
 841         }
 842
 843         inode = file->f_mapping->host;
 844         if (S_ISBLK(inode->i_mode)) {
 845                 pr_err("FILEIO Protection emulation only supported on"
 846                        " !S_ISBLK\n");
 847                 return -ENOSYS;
 848         }
 849
 850         if (fd_dev->fbd_flags & FDBD_HAS_BUFFERED_IO_WCE)
 851                 flags &= ~O_DSYNC;
 852
 853         snprintf(buf, FD_MAX_DEV_PROT_NAME, "%s.protection",
 854                  fd_dev->fd_dev_name);
 855
 856         prot_file = filp_open(buf, flags, 0600);
 857         if (IS_ERR(prot_file)) {
 858                 pr_err("filp_open(%s) failed\n", buf);
 859                 ret = PTR_ERR(prot_file);
 860                 return ret;
 861         }
 862         fd_dev->fd_prot_file = prot_file;
 863
 864         return 0;
 865 }
 866
 867 static int fd_format_prot(struct se_device *dev)
 868 {
 869         unsigned char *buf;
 870         int unit_size = FDBD_FORMAT_UNIT_SIZE * dev->dev_attrib.block_size;
 871         int ret;
 872
 873         if (!dev->dev_attrib.pi_prot_type) {
 874                 pr_err("Unable to format_prot while pi_prot_type == 0\n");
 875                 return -ENODEV;
 876         }
 877
 878         buf = vzalloc(unit_size);
 879         if (!buf) {
 880                 pr_err("Unable to allocate FILEIO prot buf\n");
 881                 return -ENOMEM;
 882         }
 883
 884         pr_debug("Using FILEIO prot_length: %llu\n",
 885                  (unsigned long long)(dev->transport->get_blocks(dev) + 1) *
 886                                         dev->prot_length);
 887
 888         memset(buf, 0xff, unit_size);
 889         ret = fd_do_prot_fill(dev, 0, dev->transport->get_blocks(dev) + 1,
 890                               buf, unit_size);
 891         vfree(buf);
 892         return ret;
 893 }
 894
 895 static void fd_free_prot(struct se_device *dev)
 896 {
 897         struct fd_dev *fd_dev = FD_DEV(dev);
 898
 899         if (!fd_dev->fd_prot_file)
 900                 return;
 901
 902         filp_close(fd_dev->fd_prot_file, NULL);
 903         fd_dev->fd_prot_file = NULL;
 904 }
 905
 906 static struct sbc_ops fd_sbc_ops = {
 907         .execute_rw             = fd_execute_rw,
 908         .execute_sync_cache     = fd_execute_sync_cache,
 909         .execute_write_same     = fd_execute_write_same,
 910         .execute_write_same_unmap = fd_execute_write_same_unmap,
 911         .execute_unmap          = fd_execute_unmap,
 912 };
 913
 914 static sense_reason_t
 915 fd_parse_cdb(struct se_cmd *cmd)
 916 {
 917         return sbc_parse_cdb(cmd, &fd_sbc_ops);
 918 }
 919
 920 DEF_TB_DEFAULT_ATTRIBS(fileio);
 921
 922 static struct configfs_attribute *fileio_backend_dev_attrs[] = {
 923         &fileio_dev_attrib_emulate_model_alias.attr,
 924         &fileio_dev_attrib_emulate_dpo.attr,
 925         &fileio_dev_attrib_emulate_fua_write.attr,
 926         &fileio_dev_attrib_emulate_fua_read.attr,
 927         &fileio_dev_attrib_emulate_write_cache.attr,
 928         &fileio_dev_attrib_emulate_ua_intlck_ctrl.attr,
 929         &fileio_dev_attrib_emulate_tas.attr,
 930         &fileio_dev_attrib_emulate_tpu.attr,
 931         &fileio_dev_attrib_emulate_tpws.attr,
 932         &fileio_dev_attrib_emulate_caw.attr,
 933         &fileio_dev_attrib_emulate_3pc.attr,
 934         &fileio_dev_attrib_pi_prot_type.attr,
 935         &fileio_dev_attrib_hw_pi_prot_type.attr,
 936         &fileio_dev_attrib_pi_prot_format.attr,
 937         &fileio_dev_attrib_enforce_pr_isids.attr,
 938         &fileio_dev_attrib_is_nonrot.attr,
 939         &fileio_dev_attrib_emulate_rest_reord.attr,
 940         &fileio_dev_attrib_force_pr_aptpl.attr,
 941         &fileio_dev_attrib_hw_block_size.attr,
 942         &fileio_dev_attrib_block_size.attr,
 943         &fileio_dev_attrib_hw_max_sectors.attr,
 944         &fileio_dev_attrib_optimal_sectors.attr,
 945         &fileio_dev_attrib_hw_queue_depth.attr,
 946         &fileio_dev_attrib_queue_depth.attr,
 947         &fileio_dev_attrib_max_unmap_lba_count.attr,
 948         &fileio_dev_attrib_max_unmap_block_desc_count.attr,
 949         &fileio_dev_attrib_unmap_granularity.attr,
 950         &fileio_dev_attrib_unmap_granularity_alignment.attr,
 951         &fileio_dev_attrib_max_write_same_len.attr,
 952         NULL,
 953 };
 954
 955 static struct se_subsystem_api fileio_template = {
 956         .name                   = "fileio",
 957         .inquiry_prod           = "FILEIO",
 958         .inquiry_rev            = FD_VERSION,
 959         .owner                  = THIS_MODULE,
 960         .attach_hba             = fd_attach_hba,
 961         .detach_hba             = fd_detach_hba,
 962         .alloc_device           = fd_alloc_device,
 963         .configure_device       = fd_configure_device,
 964         .free_device            = fd_free_device,
 965         .parse_cdb              = fd_parse_cdb,
 966         .set_configfs_dev_params = fd_set_configfs_dev_params,
 967         .show_configfs_dev_params = fd_show_configfs_dev_params,
 968         .get_device_type        = sbc_get_device_type,
 969         .get_blocks             = fd_get_blocks,
 970         .init_prot              = fd_init_prot,
 971         .format_prot            = fd_format_prot,
 972         .free_prot              = fd_free_prot,
 973 };
 974
 975 static int __init fileio_module_init(void)
 976 {
 977         struct target_backend_cits *tbc = &fileio_template.tb_cits;
 978
 979         target_core_setup_sub_cits(&fileio_template);
 980         tbc->tb_dev_attrib_cit.ct_attrs = fileio_backend_dev_attrs;
 981
 982         return transport_subsystem_register(&fileio_template);
 983 }
 984
 985 static void __exit fileio_module_exit(void)
 986 {
 987         transport_subsystem_release(&fileio_template);
 988 }
 989
 990 MODULE_DESCRIPTION("TCM FILEIO subsystem plugin");
 991 MODULE_AUTHOR("nab@Linux-iSCSI.org");
 992 MODULE_LICENSE("GPL");
 993
 994 module_init(fileio_module_init);
 995 module_exit(fileio_module_exit);