drivers/target/target_core_sbc.c

   1 /*
   2  * SCSI Block Commands (SBC) parsing and emulation.
   3  *
   4  * (c) Copyright 2002-2013 Datera, Inc.
   5  *
   6  * Nicholas A. Bellinger <nab@kernel.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/ratelimit.h>
  26 #include <linux/crc-t10dif.h>
  27 #include <asm/unaligned.h>
  28 #include <scsi/scsi_proto.h>
  29 #include <scsi/scsi_tcq.h>
  30
  31 #include <target/target_core_base.h>
  32 #include <target/target_core_backend.h>
  33 #include <target/target_core_fabric.h>
  34
  35 #include "target_core_internal.h"
  36 #include "target_core_ua.h"
  37 #include "target_core_alua.h"
  38
  39 static sense_reason_t
  40 sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
  41 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
  42
  43 static sense_reason_t
  44 sbc_emulate_readcapacity(struct se_cmd *cmd)
  45 {
  46         struct se_device *dev = cmd->se_dev;
  47         unsigned char *cdb = cmd->t_task_cdb;
  48         unsigned long long blocks_long = dev->transport->get_blocks(dev);
  49         unsigned char *rbuf;
  50         unsigned char buf[8];
  51         u32 blocks;
  52
  53         /*
  54          * SBC-2 says:
  55          *   If the PMI bit is set to zero and the LOGICAL BLOCK
  56          *   ADDRESS field is not set to zero, the device server shall
  57          *   terminate the command with CHECK CONDITION status with
  58          *   the sense key set to ILLEGAL REQUEST and the additional
  59          *   sense code set to INVALID FIELD IN CDB.
  60          *
  61          * In SBC-3, these fields are obsolete, but some SCSI
  62          * compliance tests actually check this, so we might as well
  63          * follow SBC-2.
  64          */
  65         if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
  66                 return TCM_INVALID_CDB_FIELD;
  67
  68         if (blocks_long >= 0x00000000ffffffff)
  69                 blocks = 0xffffffff;
  70         else
  71                 blocks = (u32)blocks_long;
  72
  73         buf[0] = (blocks >> 24) & 0xff;
  74         buf[1] = (blocks >> 16) & 0xff;
  75         buf[2] = (blocks >> 8) & 0xff;
  76         buf[3] = blocks & 0xff;
  77         buf[4] = (dev->dev_attrib.block_size >> 24) & 0xff;
  78         buf[5] = (dev->dev_attrib.block_size >> 16) & 0xff;
  79         buf[6] = (dev->dev_attrib.block_size >> 8) & 0xff;
  80         buf[7] = dev->dev_attrib.block_size & 0xff;
  81
  82         rbuf = transport_kmap_data_sg(cmd);
  83         if (rbuf) {
  84                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
  85                 transport_kunmap_data_sg(cmd);
  86         }
  87
  88         target_complete_cmd_with_length(cmd, GOOD, 8);
  89         return 0;
  90 }
  91
  92 static sense_reason_t
  93 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  94 {
  95         struct se_device *dev = cmd->se_dev;
  96         struct se_session *sess = cmd->se_sess;
  97         int pi_prot_type = dev->dev_attrib.pi_prot_type;
  98
  99         unsigned char *rbuf;
 100         unsigned char buf[32];
 101         unsigned long long blocks = dev->transport->get_blocks(dev);
 102
 103         memset(buf, 0, sizeof(buf));
 104         buf[0] = (blocks >> 56) & 0xff;
 105         buf[1] = (blocks >> 48) & 0xff;
 106         buf[2] = (blocks >> 40) & 0xff;
 107         buf[3] = (blocks >> 32) & 0xff;
 108         buf[4] = (blocks >> 24) & 0xff;
 109         buf[5] = (blocks >> 16) & 0xff;
 110         buf[6] = (blocks >> 8) & 0xff;
 111         buf[7] = blocks & 0xff;
 112         buf[8] = (dev->dev_attrib.block_size >> 24) & 0xff;
 113         buf[9] = (dev->dev_attrib.block_size >> 16) & 0xff;
 114         buf[10] = (dev->dev_attrib.block_size >> 8) & 0xff;
 115         buf[11] = dev->dev_attrib.block_size & 0xff;
 116         /*
 117          * Set P_TYPE and PROT_EN bits for DIF support
 118          */
 119         if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
 120                 /*
 121                  * Only override a device's pi_prot_type if no T10-PI is
 122                  * available, and sess_prot_type has been explicitly enabled.
 123                  */
 124                 if (!pi_prot_type)
 125                         pi_prot_type = sess->sess_prot_type;
 126
 127                 if (pi_prot_type)
 128                         buf[12] = (pi_prot_type - 1) << 1 | 0x1;
 129         }
 130
 131         if (dev->transport->get_lbppbe)
 132                 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
 133
 134         if (dev->transport->get_alignment_offset_lbas) {
 135                 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
 136                 buf[14] = (lalba >> 8) & 0x3f;
 137                 buf[15] = lalba & 0xff;
 138         }
 139
 140         /*
 141          * Set Thin Provisioning Enable bit following sbc3r22 in section
 142          * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
 143          */
 144         if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws)
 145                 buf[14] |= 0x80;
 146
 147         rbuf = transport_kmap_data_sg(cmd);
 148         if (rbuf) {
 149                 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
 150                 transport_kunmap_data_sg(cmd);
 151         }
 152
 153         target_complete_cmd_with_length(cmd, GOOD, 32);
 154         return 0;
 155 }
 156
 157 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
 158 {
 159         u32 num_blocks;
 160
 161         if (cmd->t_task_cdb[0] == WRITE_SAME)
 162                 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 163         else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 164                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 165         else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 166                 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 167
 168         /*
 169          * Use the explicit range when non zero is supplied, otherwise calculate
 170          * the remaining range based on ->get_blocks() - starting LBA.
 171          */
 172         if (num_blocks)
 173                 return num_blocks;
 174
 175         return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 176                 cmd->t_task_lba + 1;
 177 }
 178 EXPORT_SYMBOL(sbc_get_write_same_sectors);
 179
 180 static sense_reason_t
 181 sbc_execute_write_same_unmap(struct se_cmd *cmd)
 182 {
 183         struct sbc_ops *ops = cmd->protocol_data;
 184         sector_t nolb = sbc_get_write_same_sectors(cmd);
 185         sense_reason_t ret;
 186
 187         if (nolb) {
 188                 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
 189                 if (ret)
 190                         return ret;
 191         }
 192
 193         target_complete_cmd(cmd, GOOD);
 194         return 0;
 195 }
 196
 197 static sense_reason_t
 198 sbc_emulate_noop(struct se_cmd *cmd)
 199 {
 200         target_complete_cmd(cmd, GOOD);
 201         return 0;
 202 }
 203
 204 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 205 {
 206         return cmd->se_dev->dev_attrib.block_size * sectors;
 207 }
 208
 209 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 210 {
 211         /*
 212          * Use 8-bit sector value.  SBC-3 says:
 213          *
 214          *   A TRANSFER LENGTH field set to zero specifies that 256
 215          *   logical blocks shall be written.  Any other value
 216          *   specifies the number of logical blocks that shall be
 217          *   written.
 218          */
 219         return cdb[4] ? : 256;
 220 }
 221
 222 static inline u32 transport_get_sectors_10(unsigned char *cdb)
 223 {
 224         return (u32)(cdb[7] << 8) + cdb[8];
 225 }
 226
 227 static inline u32 transport_get_sectors_12(unsigned char *cdb)
 228 {
 229         return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
 230 }
 231
 232 static inline u32 transport_get_sectors_16(unsigned char *cdb)
 233 {
 234         return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
 235                     (cdb[12] << 8) + cdb[13];
 236 }
 237
 238 /*
 239  * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 240  */
 241 static inline u32 transport_get_sectors_32(unsigned char *cdb)
 242 {
 243         return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
 244                     (cdb[30] << 8) + cdb[31];
 245
 246 }
 247
 248 static inline u32 transport_lba_21(unsigned char *cdb)
 249 {
 250         return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
 251 }
 252
 253 static inline u32 transport_lba_32(unsigned char *cdb)
 254 {
 255         return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 256 }
 257
 258 static inline unsigned long long transport_lba_64(unsigned char *cdb)
 259 {
 260         unsigned int __v1, __v2;
 261
 262         __v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 263         __v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
 264
 265         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 266 }
 267
 268 /*
 269  * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 270  */
 271 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 272 {
 273         unsigned int __v1, __v2;
 274
 275         __v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
 276         __v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
 277
 278         return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 279 }
 280
 281 static sense_reason_t
 282 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
 283 {
 284         struct se_device *dev = cmd->se_dev;
 285         sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 286         unsigned int sectors = sbc_get_write_same_sectors(cmd);
 287         sense_reason_t ret;
 288
 289         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 290                 pr_err("WRITE_SAME PBDATA and LBDATA"
 291                         " bits not supported for Block Discard"
 292                         " Emulation\n");
 293                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 294         }
 295         if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 296                 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 297                         sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 298                 return TCM_INVALID_CDB_FIELD;
 299         }
 300         /*
 301          * Sanity check for LBA wrap and request past end of device.
 302          */
 303         if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 304             ((cmd->t_task_lba + sectors) > end_lba)) {
 305                 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
 306                        (unsigned long long)end_lba, cmd->t_task_lba, sectors);
 307                 return TCM_ADDRESS_OUT_OF_RANGE;
 308         }
 309
 310         /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 311         if (flags[0] & 0x10) {
 312                 pr_warn("WRITE SAME with ANCHOR not supported\n");
 313                 return TCM_INVALID_CDB_FIELD;
 314         }
 315         /*
 316          * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 317          * translated into block discard requests within backend code.
 318          */
 319         if (flags[0] & 0x08) {
 320                 if (!ops->execute_unmap)
 321                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 322
 323                 if (!dev->dev_attrib.emulate_tpws) {
 324                         pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
 325                                " has emulate_tpws disabled\n");
 326                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 327                 }
 328                 cmd->execute_cmd = sbc_execute_write_same_unmap;
 329                 return 0;
 330         }
 331         if (!ops->execute_write_same)
 332                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 333
 334         ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
 335         if (ret)
 336                 return ret;
 337
 338         cmd->execute_cmd = ops->execute_write_same;
 339         return 0;
 340 }
 341
 342 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success)
 343 {
 344         unsigned char *buf, *addr;
 345         struct scatterlist *sg;
 346         unsigned int offset;
 347         sense_reason_t ret = TCM_NO_SENSE;
 348         int i, count;
 349         /*
 350          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 351          *
 352          * 1) read the specified logical block(s);
 353          * 2) transfer logical blocks from the data-out buffer;
 354          * 3) XOR the logical blocks transferred from the data-out buffer with
 355          *    the logical blocks read, storing the resulting XOR data in a buffer;
 356          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 357          *    blocks transferred from the data-out buffer; and
 358          * 5) transfer the resulting XOR data to the data-in buffer.
 359          */
 360         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 361         if (!buf) {
 362                 pr_err("Unable to allocate xor_callback buf\n");
 363                 return TCM_OUT_OF_RESOURCES;
 364         }
 365         /*
 366          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 367          * into the locally allocated *buf
 368          */
 369         sg_copy_to_buffer(cmd->t_data_sg,
 370                           cmd->t_data_nents,
 371                           buf,
 372                           cmd->data_length);
 373
 374         /*
 375          * Now perform the XOR against the BIDI read memory located at
 376          * cmd->t_mem_bidi_list
 377          */
 378
 379         offset = 0;
 380         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 381                 addr = kmap_atomic(sg_page(sg));
 382                 if (!addr) {
 383                         ret = TCM_OUT_OF_RESOURCES;
 384                         goto out;
 385                 }
 386
 387                 for (i = 0; i < sg->length; i++)
 388                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 389
 390                 offset += sg->length;
 391                 kunmap_atomic(addr);
 392         }
 393
 394 out:
 395         kfree(buf);
 396         return ret;
 397 }
 398
 399 static sense_reason_t
 400 sbc_execute_rw(struct se_cmd *cmd)
 401 {
 402         struct sbc_ops *ops = cmd->protocol_data;
 403
 404         return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 405                                cmd->data_direction);
 406 }
 407
 408 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success)
 409 {
 410         struct se_device *dev = cmd->se_dev;
 411
 412         /*
 413          * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
 414          * within target_complete_ok_work() if the command was successfully
 415          * sent to the backend driver.
 416          */
 417         spin_lock_irq(&cmd->t_state_lock);
 418         if ((cmd->transport_state & CMD_T_SENT) && !cmd->scsi_status)
 419                 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 420         spin_unlock_irq(&cmd->t_state_lock);
 421
 422         /*
 423          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 424          * before the original READ I/O submission.
 425          */
 426         up(&dev->caw_sem);
 427
 428         return TCM_NO_SENSE;
 429 }
 430
 431 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success)
 432 {
 433         struct se_device *dev = cmd->se_dev;
 434         struct scatterlist *write_sg = NULL, *sg;
 435         unsigned char *buf = NULL, *addr;
 436         struct sg_mapping_iter m;
 437         unsigned int offset = 0, len;
 438         unsigned int nlbas = cmd->t_task_nolb;
 439         unsigned int block_size = dev->dev_attrib.block_size;
 440         unsigned int compare_len = (nlbas * block_size);
 441         sense_reason_t ret = TCM_NO_SENSE;
 442         int rc, i;
 443
 444         /*
 445          * Handle early failure in transport_generic_request_failure(),
 446          * which will not have taken ->caw_sem yet..
 447          */
 448         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 449                 return TCM_NO_SENSE;
 450         /*
 451          * Handle special case for zero-length COMPARE_AND_WRITE
 452          */
 453         if (!cmd->data_length)
 454                 goto out;
 455         /*
 456          * Immediately exit + release dev->caw_sem if command has already
 457          * been failed with a non-zero SCSI status.
 458          */
 459         if (cmd->scsi_status) {
 460                 pr_err("compare_and_write_callback: non zero scsi_status:"
 461                         " 0x%02x\n", cmd->scsi_status);
 462                 goto out;
 463         }
 464
 465         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 466         if (!buf) {
 467                 pr_err("Unable to allocate compare_and_write buf\n");
 468                 ret = TCM_OUT_OF_RESOURCES;
 469                 goto out;
 470         }
 471
 472         write_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
 473                            GFP_KERNEL);
 474         if (!write_sg) {
 475                 pr_err("Unable to allocate compare_and_write sg\n");
 476                 ret = TCM_OUT_OF_RESOURCES;
 477                 goto out;
 478         }
 479         sg_init_table(write_sg, cmd->t_data_nents);
 480         /*
 481          * Setup verify and write data payloads from total NumberLBAs.
 482          */
 483         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 484                                cmd->data_length);
 485         if (!rc) {
 486                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 487                 ret = TCM_OUT_OF_RESOURCES;
 488                 goto out;
 489         }
 490         /*
 491          * Compare against SCSI READ payload against verify payload
 492          */
 493         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 494                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 495                 if (!addr) {
 496                         ret = TCM_OUT_OF_RESOURCES;
 497                         goto out;
 498                 }
 499
 500                 len = min(sg->length, compare_len);
 501
 502                 if (memcmp(addr, buf + offset, len)) {
 503                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 504                                 addr, buf + offset);
 505                         kunmap_atomic(addr);
 506                         goto miscompare;
 507                 }
 508                 kunmap_atomic(addr);
 509
 510                 offset += len;
 511                 compare_len -= len;
 512                 if (!compare_len)
 513                         break;
 514         }
 515
 516         i = 0;
 517         len = cmd->t_task_nolb * block_size;
 518         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 519         /*
 520          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 521          */
 522         while (len) {
 523                 sg_miter_next(&m);
 524
 525                 if (block_size < PAGE_SIZE) {
 526                         sg_set_page(&write_sg[i], m.page, block_size,
 527                                     block_size);
 528                 } else {
 529                         sg_miter_next(&m);
 530                         sg_set_page(&write_sg[i], m.page, block_size,
 531                                     0);
 532                 }
 533                 len -= block_size;
 534                 i++;
 535         }
 536         sg_miter_stop(&m);
 537         /*
 538          * Save the original SGL + nents values before updating to new
 539          * assignments, to be released in transport_free_pages() ->
 540          * transport_reset_sgl_orig()
 541          */
 542         cmd->t_data_sg_orig = cmd->t_data_sg;
 543         cmd->t_data_sg = write_sg;
 544         cmd->t_data_nents_orig = cmd->t_data_nents;
 545         cmd->t_data_nents = 1;
 546
 547         cmd->sam_task_attr = TCM_HEAD_TAG;
 548         cmd->transport_complete_callback = compare_and_write_post;
 549         /*
 550          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 551          * for submitting the adjusted SGL to write instance user-data.
 552          */
 553         cmd->execute_cmd = sbc_execute_rw;
 554
 555         spin_lock_irq(&cmd->t_state_lock);
 556         cmd->t_state = TRANSPORT_PROCESSING;
 557         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 558         spin_unlock_irq(&cmd->t_state_lock);
 559
 560         __target_execute_cmd(cmd);
 561
 562         kfree(buf);
 563         return ret;
 564
 565 miscompare:
 566         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 567                 dev->transport->name);
 568         ret = TCM_MISCOMPARE_VERIFY;
 569 out:
 570         /*
 571          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 572          * sbc_compare_and_write() before the original READ I/O submission.
 573          */
 574         up(&dev->caw_sem);
 575         kfree(write_sg);
 576         kfree(buf);
 577         return ret;
 578 }
 579
 580 static sense_reason_t
 581 sbc_compare_and_write(struct se_cmd *cmd)
 582 {
 583         struct sbc_ops *ops = cmd->protocol_data;
 584         struct se_device *dev = cmd->se_dev;
 585         sense_reason_t ret;
 586         int rc;
 587         /*
 588          * Submit the READ first for COMPARE_AND_WRITE to perform the
 589          * comparision using SGLs at cmd->t_bidi_data_sg..
 590          */
 591         rc = down_interruptible(&dev->caw_sem);
 592         if (rc != 0) {
 593                 cmd->transport_complete_callback = NULL;
 594                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 595         }
 596         /*
 597          * Reset cmd->data_length to individual block_size in order to not
 598          * confuse backend drivers that depend on this value matching the
 599          * size of the I/O being submitted.
 600          */
 601         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 602
 603         ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 604                               DMA_FROM_DEVICE);
 605         if (ret) {
 606                 cmd->transport_complete_callback = NULL;
 607                 up(&dev->caw_sem);
 608                 return ret;
 609         }
 610         /*
 611          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 612          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 613          * of WRITE instance user-data.
 614          */
 615         return TCM_NO_SENSE;
 616 }
 617
 618 static int
 619 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 620                        bool is_write, struct se_cmd *cmd)
 621 {
 622         if (is_write) {
 623                 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 624                                protect ? TARGET_PROT_DOUT_PASS :
 625                                TARGET_PROT_DOUT_INSERT;
 626                 switch (protect) {
 627                 case 0x0:
 628                 case 0x3:
 629                         cmd->prot_checks = 0;
 630                         break;
 631                 case 0x1:
 632                 case 0x5:
 633                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 634                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 635                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 636                         break;
 637                 case 0x2:
 638                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 639                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 640                         break;
 641                 case 0x4:
 642                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 643                         break;
 644                 default:
 645                         pr_err("Unsupported protect field %d\n", protect);
 646                         return -EINVAL;
 647                 }
 648         } else {
 649                 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 650                                protect ? TARGET_PROT_DIN_PASS :
 651                                TARGET_PROT_DIN_STRIP;
 652                 switch (protect) {
 653                 case 0x0:
 654                 case 0x1:
 655                 case 0x5:
 656                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 657                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 658                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 659                         break;
 660                 case 0x2:
 661                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 662                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 663                         break;
 664                 case 0x3:
 665                         cmd->prot_checks = 0;
 666                         break;
 667                 case 0x4:
 668                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 669                         break;
 670                 default:
 671                         pr_err("Unsupported protect field %d\n", protect);
 672                         return -EINVAL;
 673                 }
 674         }
 675
 676         return 0;
 677 }
 678
 679 static sense_reason_t
 680 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 681                u32 sectors, bool is_write)
 682 {
 683         u8 protect = cdb[1] >> 5;
 684         int sp_ops = cmd->se_sess->sup_prot_ops;
 685         int pi_prot_type = dev->dev_attrib.pi_prot_type;
 686         bool fabric_prot = false;
 687
 688         if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 689                 if (unlikely(protect &&
 690                     !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 691                         pr_err("CDB contains protect bit, but device + fabric does"
 692                                " not advertise PROTECT=1 feature bit\n");
 693                         return TCM_INVALID_CDB_FIELD;
 694                 }
 695                 if (cmd->prot_pto)
 696                         return TCM_NO_SENSE;
 697         }
 698
 699         switch (dev->dev_attrib.pi_prot_type) {
 700         case TARGET_DIF_TYPE3_PROT:
 701                 cmd->reftag_seed = 0xffffffff;
 702                 break;
 703         case TARGET_DIF_TYPE2_PROT:
 704                 if (protect)
 705                         return TCM_INVALID_CDB_FIELD;
 706
 707                 cmd->reftag_seed = cmd->t_task_lba;
 708                 break;
 709         case TARGET_DIF_TYPE1_PROT:
 710                 cmd->reftag_seed = cmd->t_task_lba;
 711                 break;
 712         case TARGET_DIF_TYPE0_PROT:
 713                 /*
 714                  * See if the fabric supports T10-PI, and the session has been
 715                  * configured to allow export PROTECT=1 feature bit with backend
 716                  * devices that don't support T10-PI.
 717                  */
 718                 fabric_prot = is_write ?
 719                               !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 720                               !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 721
 722                 if (fabric_prot && cmd->se_sess->sess_prot_type) {
 723                         pi_prot_type = cmd->se_sess->sess_prot_type;
 724                         break;
 725                 }
 726                 if (!protect)
 727                         return TCM_NO_SENSE;
 728                 /* Fallthrough */
 729         default:
 730                 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 731                        "PROTECT: 0x%02x\n", cdb[0], protect);
 732                 return TCM_INVALID_CDB_FIELD;
 733         }
 734
 735         if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 736                 return TCM_INVALID_CDB_FIELD;
 737
 738         cmd->prot_type = pi_prot_type;
 739         cmd->prot_length = dev->prot_length * sectors;
 740
 741         /**
 742          * In case protection information exists over the wire
 743          * we modify command data length to describe pure data.
 744          * The actual transfer length is data length + protection
 745          * length
 746          **/
 747         if (protect)
 748                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 749
 750         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 751                  "prot_op=%d prot_checks=%d\n",
 752                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 753                  cmd->prot_op, cmd->prot_checks);
 754
 755         return TCM_NO_SENSE;
 756 }
 757
 758 static int
 759 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 760 {
 761         if (cdb[1] & 0x10) {
 762                 /* see explanation in spc_emulate_modesense */
 763                 if (!target_check_fua(dev)) {
 764                         pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 765                                " does not advertise support for DPO\n", cdb[0]);
 766                         return -EINVAL;
 767                 }
 768         }
 769         if (cdb[1] & 0x8) {
 770                 if (!target_check_fua(dev)) {
 771                         pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 772                                " does not advertise support for FUA write\n",
 773                                cdb[0]);
 774                         return -EINVAL;
 775                 }
 776                 cmd->se_cmd_flags |= SCF_FUA;
 777         }
 778         return 0;
 779 }
 780
 781 sense_reason_t
 782 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 783 {
 784         struct se_device *dev = cmd->se_dev;
 785         unsigned char *cdb = cmd->t_task_cdb;
 786         unsigned int size;
 787         u32 sectors = 0;
 788         sense_reason_t ret;
 789
 790         cmd->protocol_data = ops;
 791
 792         switch (cdb[0]) {
 793         case READ_6:
 794                 sectors = transport_get_sectors_6(cdb);
 795                 cmd->t_task_lba = transport_lba_21(cdb);
 796                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 797                 cmd->execute_cmd = sbc_execute_rw;
 798                 break;
 799         case READ_10:
 800                 sectors = transport_get_sectors_10(cdb);
 801                 cmd->t_task_lba = transport_lba_32(cdb);
 802
 803                 if (sbc_check_dpofua(dev, cmd, cdb))
 804                         return TCM_INVALID_CDB_FIELD;
 805
 806                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 807                 if (ret)
 808                         return ret;
 809
 810                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 811                 cmd->execute_cmd = sbc_execute_rw;
 812                 break;
 813         case READ_12:
 814                 sectors = transport_get_sectors_12(cdb);
 815                 cmd->t_task_lba = transport_lba_32(cdb);
 816
 817                 if (sbc_check_dpofua(dev, cmd, cdb))
 818                         return TCM_INVALID_CDB_FIELD;
 819
 820                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 821                 if (ret)
 822                         return ret;
 823
 824                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 825                 cmd->execute_cmd = sbc_execute_rw;
 826                 break;
 827         case READ_16:
 828                 sectors = transport_get_sectors_16(cdb);
 829                 cmd->t_task_lba = transport_lba_64(cdb);
 830
 831                 if (sbc_check_dpofua(dev, cmd, cdb))
 832                         return TCM_INVALID_CDB_FIELD;
 833
 834                 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
 835                 if (ret)
 836                         return ret;
 837
 838                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 839                 cmd->execute_cmd = sbc_execute_rw;
 840                 break;
 841         case WRITE_6:
 842                 sectors = transport_get_sectors_6(cdb);
 843                 cmd->t_task_lba = transport_lba_21(cdb);
 844                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 845                 cmd->execute_cmd = sbc_execute_rw;
 846                 break;
 847         case WRITE_10:
 848         case WRITE_VERIFY:
 849                 sectors = transport_get_sectors_10(cdb);
 850                 cmd->t_task_lba = transport_lba_32(cdb);
 851
 852                 if (sbc_check_dpofua(dev, cmd, cdb))
 853                         return TCM_INVALID_CDB_FIELD;
 854
 855                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 856                 if (ret)
 857                         return ret;
 858
 859                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 860                 cmd->execute_cmd = sbc_execute_rw;
 861                 break;
 862         case WRITE_12:
 863                 sectors = transport_get_sectors_12(cdb);
 864                 cmd->t_task_lba = transport_lba_32(cdb);
 865
 866                 if (sbc_check_dpofua(dev, cmd, cdb))
 867                         return TCM_INVALID_CDB_FIELD;
 868
 869                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 870                 if (ret)
 871                         return ret;
 872
 873                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 874                 cmd->execute_cmd = sbc_execute_rw;
 875                 break;
 876         case WRITE_16:
 877                 sectors = transport_get_sectors_16(cdb);
 878                 cmd->t_task_lba = transport_lba_64(cdb);
 879
 880                 if (sbc_check_dpofua(dev, cmd, cdb))
 881                         return TCM_INVALID_CDB_FIELD;
 882
 883                 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
 884                 if (ret)
 885                         return ret;
 886
 887                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 888                 cmd->execute_cmd = sbc_execute_rw;
 889                 break;
 890         case XDWRITEREAD_10:
 891                 if (cmd->data_direction != DMA_TO_DEVICE ||
 892                     !(cmd->se_cmd_flags & SCF_BIDI))
 893                         return TCM_INVALID_CDB_FIELD;
 894                 sectors = transport_get_sectors_10(cdb);
 895
 896                 if (sbc_check_dpofua(dev, cmd, cdb))
 897                         return TCM_INVALID_CDB_FIELD;
 898
 899                 cmd->t_task_lba = transport_lba_32(cdb);
 900                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 901
 902                 /*
 903                  * Setup BIDI XOR callback to be run after I/O completion.
 904                  */
 905                 cmd->execute_cmd = sbc_execute_rw;
 906                 cmd->transport_complete_callback = &xdreadwrite_callback;
 907                 break;
 908         case VARIABLE_LENGTH_CMD:
 909         {
 910                 u16 service_action = get_unaligned_be16(&cdb[8]);
 911                 switch (service_action) {
 912                 case XDWRITEREAD_32:
 913                         sectors = transport_get_sectors_32(cdb);
 914
 915                         if (sbc_check_dpofua(dev, cmd, cdb))
 916                                 return TCM_INVALID_CDB_FIELD;
 917                         /*
 918                          * Use WRITE_32 and READ_32 opcodes for the emulated
 919                          * XDWRITE_READ_32 logic.
 920                          */
 921                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 922                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 923
 924                         /*
 925                          * Setup BIDI XOR callback to be run during after I/O
 926                          * completion.
 927                          */
 928                         cmd->execute_cmd = sbc_execute_rw;
 929                         cmd->transport_complete_callback = &xdreadwrite_callback;
 930                         break;
 931                 case WRITE_SAME_32:
 932                         sectors = transport_get_sectors_32(cdb);
 933                         if (!sectors) {
 934                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 935                                        " supported\n");
 936                                 return TCM_INVALID_CDB_FIELD;
 937                         }
 938
 939                         size = sbc_get_size(cmd, 1);
 940                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 941
 942                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 943                         if (ret)
 944                                 return ret;
 945                         break;
 946                 default:
 947                         pr_err("VARIABLE_LENGTH_CMD service action"
 948                                 " 0x%04x not supported\n", service_action);
 949                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 950                 }
 951                 break;
 952         }
 953         case COMPARE_AND_WRITE:
 954                 sectors = cdb[13];
 955                 /*
 956                  * Currently enforce COMPARE_AND_WRITE for a single sector
 957                  */
 958                 if (sectors > 1) {
 959                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 960                                " than 1\n", sectors);
 961                         return TCM_INVALID_CDB_FIELD;
 962                 }
 963                 /*
 964                  * Double size because we have two buffers, note that
 965                  * zero is not an error..
 966                  */
 967                 size = 2 * sbc_get_size(cmd, sectors);
 968                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 969                 cmd->t_task_nolb = sectors;
 970                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
 971                 cmd->execute_cmd = sbc_compare_and_write;
 972                 cmd->transport_complete_callback = compare_and_write_callback;
 973                 break;
 974         case READ_CAPACITY:
 975                 size = READ_CAP_LEN;
 976                 cmd->execute_cmd = sbc_emulate_readcapacity;
 977                 break;
 978         case SERVICE_ACTION_IN_16:
 979                 switch (cmd->t_task_cdb[1] & 0x1f) {
 980                 case SAI_READ_CAPACITY_16:
 981                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
 982                         break;
 983                 case SAI_REPORT_REFERRALS:
 984                         cmd->execute_cmd = target_emulate_report_referrals;
 985                         break;
 986                 default:
 987                         pr_err("Unsupported SA: 0x%02x\n",
 988                                 cmd->t_task_cdb[1] & 0x1f);
 989                         return TCM_INVALID_CDB_FIELD;
 990                 }
 991                 size = (cdb[10] << 24) | (cdb[11] << 16) |
 992                        (cdb[12] << 8) | cdb[13];
 993                 break;
 994         case SYNCHRONIZE_CACHE:
 995         case SYNCHRONIZE_CACHE_16:
 996                 if (cdb[0] == SYNCHRONIZE_CACHE) {
 997                         sectors = transport_get_sectors_10(cdb);
 998                         cmd->t_task_lba = transport_lba_32(cdb);
 999                 } else {
1000                         sectors = transport_get_sectors_16(cdb);
1001                         cmd->t_task_lba = transport_lba_64(cdb);
1002                 }
1003                 if (ops->execute_sync_cache) {
1004                         cmd->execute_cmd = ops->execute_sync_cache;
1005                         goto check_lba;
1006                 }
1007                 size = 0;
1008                 cmd->execute_cmd = sbc_emulate_noop;
1009                 break;
1010         case UNMAP:
1011                 if (!ops->execute_unmap)
1012                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1013
1014                 if (!dev->dev_attrib.emulate_tpu) {
1015                         pr_err("Got UNMAP, but backend device has"
1016                                " emulate_tpu disabled\n");
1017                         return TCM_UNSUPPORTED_SCSI_OPCODE;
1018                 }
1019                 size = get_unaligned_be16(&cdb[7]);
1020                 cmd->execute_cmd = sbc_execute_unmap;
1021                 break;
1022         case WRITE_SAME_16:
1023                 sectors = transport_get_sectors_16(cdb);
1024                 if (!sectors) {
1025                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1026                         return TCM_INVALID_CDB_FIELD;
1027                 }
1028
1029                 size = sbc_get_size(cmd, 1);
1030                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1031
1032                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1033                 if (ret)
1034                         return ret;
1035                 break;
1036         case WRITE_SAME:
1037                 sectors = transport_get_sectors_10(cdb);
1038                 if (!sectors) {
1039                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1040                         return TCM_INVALID_CDB_FIELD;
1041                 }
1042
1043                 size = sbc_get_size(cmd, 1);
1044                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1045
1046                 /*
1047                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1048                  * of byte 1 bit 3 UNMAP instead of original reserved field
1049                  */
1050                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1051                 if (ret)
1052                         return ret;
1053                 break;
1054         case VERIFY:
1055                 size = 0;
1056                 sectors = transport_get_sectors_10(cdb);
1057                 cmd->t_task_lba = transport_lba_32(cdb);
1058                 cmd->execute_cmd = sbc_emulate_noop;
1059                 goto check_lba;
1060         case REZERO_UNIT:
1061         case SEEK_6:
1062         case SEEK_10:
1063                 /*
1064                  * There are still clients out there which use these old SCSI-2
1065                  * commands. This mainly happens when running VMs with legacy
1066                  * guest systems, connected via SCSI command pass-through to
1067                  * iSCSI targets. Make them happy and return status GOOD.
1068                  */
1069                 size = 0;
1070                 cmd->execute_cmd = sbc_emulate_noop;
1071                 break;
1072         default:
1073                 ret = spc_parse_cdb(cmd, &size);
1074                 if (ret)
1075                         return ret;
1076         }
1077
1078         /* reject any command that we don't have a handler for */
1079         if (!cmd->execute_cmd)
1080                 return TCM_UNSUPPORTED_SCSI_OPCODE;
1081
1082         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1083                 unsigned long long end_lba;
1084 check_lba:
1085                 end_lba = dev->transport->get_blocks(dev) + 1;
1086                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1087                     ((cmd->t_task_lba + sectors) > end_lba)) {
1088                         pr_err("cmd exceeds last lba %llu "
1089                                 "(lba %llu, sectors %u)\n",
1090                                 end_lba, cmd->t_task_lba, sectors);
1091                         return TCM_ADDRESS_OUT_OF_RANGE;
1092                 }
1093
1094                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1095                         size = sbc_get_size(cmd, sectors);
1096         }
1097
1098         return target_cmd_size_check(cmd, size);
1099 }
1100 EXPORT_SYMBOL(sbc_parse_cdb);
1101
1102 u32 sbc_get_device_type(struct se_device *dev)
1103 {
1104         return TYPE_DISK;
1105 }
1106 EXPORT_SYMBOL(sbc_get_device_type);
1107
1108 static sense_reason_t
1109 sbc_execute_unmap(struct se_cmd *cmd)
1110 {
1111         struct sbc_ops *ops = cmd->protocol_data;
1112         struct se_device *dev = cmd->se_dev;
1113         unsigned char *buf, *ptr = NULL;
1114         sector_t lba;
1115         int size;
1116         u32 range;
1117         sense_reason_t ret = 0;
1118         int dl, bd_dl;
1119
1120         /* We never set ANC_SUP */
1121         if (cmd->t_task_cdb[1])
1122                 return TCM_INVALID_CDB_FIELD;
1123
1124         if (cmd->data_length == 0) {
1125                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1126                 return 0;
1127         }
1128
1129         if (cmd->data_length < 8) {
1130                 pr_warn("UNMAP parameter list length %u too small\n",
1131                         cmd->data_length);
1132                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1133         }
1134
1135         buf = transport_kmap_data_sg(cmd);
1136         if (!buf)
1137                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1138
1139         dl = get_unaligned_be16(&buf[0]);
1140         bd_dl = get_unaligned_be16(&buf[2]);
1141
1142         size = cmd->data_length - 8;
1143         if (bd_dl > size)
1144                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1145                         cmd->data_length, bd_dl);
1146         else
1147                 size = bd_dl;
1148
1149         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1150                 ret = TCM_INVALID_PARAMETER_LIST;
1151                 goto err;
1152         }
1153
1154         /* First UNMAP block descriptor starts at 8 byte offset */
1155         ptr = &buf[8];
1156         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1157                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1158
1159         while (size >= 16) {
1160                 lba = get_unaligned_be64(&ptr[0]);
1161                 range = get_unaligned_be32(&ptr[8]);
1162                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1163                                  (unsigned long long)lba, range);
1164
1165                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1166                         ret = TCM_INVALID_PARAMETER_LIST;
1167                         goto err;
1168                 }
1169
1170                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1171                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1172                         goto err;
1173                 }
1174
1175                 ret = ops->execute_unmap(cmd, lba, range);
1176                 if (ret)
1177                         goto err;
1178
1179                 ptr += 16;
1180                 size -= 16;
1181         }
1182
1183 err:
1184         transport_kunmap_data_sg(cmd);
1185         if (!ret)
1186                 target_complete_cmd(cmd, GOOD);
1187         return ret;
1188 }
1189
1190 void
1191 sbc_dif_generate(struct se_cmd *cmd)
1192 {
1193         struct se_device *dev = cmd->se_dev;
1194         struct se_dif_v1_tuple *sdt;
1195         struct scatterlist *dsg = cmd->t_data_sg, *psg;
1196         sector_t sector = cmd->t_task_lba;
1197         void *daddr, *paddr;
1198         int i, j, offset = 0;
1199         unsigned int block_size = dev->dev_attrib.block_size;
1200
1201         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1202                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1203                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1204
1205                 for (j = 0; j < psg->length;
1206                                 j += sizeof(struct se_dif_v1_tuple)) {
1207                         __u16 crc;
1208                         unsigned int avail;
1209
1210                         if (offset >= dsg->length) {
1211                                 offset -= dsg->length;
1212                                 kunmap_atomic(daddr - dsg->offset);
1213                                 dsg = sg_next(dsg);
1214                                 if (!dsg) {
1215                                         kunmap_atomic(paddr - psg->offset);
1216                                         return;
1217                                 }
1218                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1219                         }
1220
1221                         sdt = paddr + j;
1222                         avail = min(block_size, dsg->length - offset);
1223                         crc = crc_t10dif(daddr + offset, avail);
1224                         if (avail < block_size) {
1225                                 kunmap_atomic(daddr - dsg->offset);
1226                                 dsg = sg_next(dsg);
1227                                 if (!dsg) {
1228                                         kunmap_atomic(paddr - psg->offset);
1229                                         return;
1230                                 }
1231                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1232                                 offset = block_size - avail;
1233                                 crc = crc_t10dif_update(crc, daddr, offset);
1234                         } else {
1235                                 offset += block_size;
1236                         }
1237
1238                         sdt->guard_tag = cpu_to_be16(crc);
1239                         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1240                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1241                         sdt->app_tag = 0;
1242
1243                         pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1244                                  " app_tag: 0x%04x ref_tag: %u\n",
1245                                  (cmd->data_direction == DMA_TO_DEVICE) ?
1246                                  "WRITE" : "READ", (unsigned long long)sector,
1247                                  sdt->guard_tag, sdt->app_tag,
1248                                  be32_to_cpu(sdt->ref_tag));
1249
1250                         sector++;
1251                 }
1252
1253                 kunmap_atomic(daddr - dsg->offset);
1254                 kunmap_atomic(paddr - psg->offset);
1255         }
1256 }
1257
1258 static sense_reason_t
1259 sbc_dif_v1_verify(struct se_cmd *cmd, struct se_dif_v1_tuple *sdt,
1260                   __u16 crc, sector_t sector, unsigned int ei_lba)
1261 {
1262         __be16 csum;
1263
1264         if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1265                 goto check_ref;
1266
1267         csum = cpu_to_be16(crc);
1268
1269         if (sdt->guard_tag != csum) {
1270                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1271                         " csum 0x%04x\n", (unsigned long long)sector,
1272                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1273                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1274         }
1275
1276 check_ref:
1277         if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1278                 return 0;
1279
1280         if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1281             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1282                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1283                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1284                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1285                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1286         }
1287
1288         if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1289             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1290                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1291                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1292                         be32_to_cpu(sdt->ref_tag), ei_lba);
1293                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1294         }
1295
1296         return 0;
1297 }
1298
1299 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1300                        struct scatterlist *sg, int sg_off)
1301 {
1302         struct se_device *dev = cmd->se_dev;
1303         struct scatterlist *psg;
1304         void *paddr, *addr;
1305         unsigned int i, len, left;
1306         unsigned int offset = sg_off;
1307
1308         if (!sg)
1309                 return;
1310
1311         left = sectors * dev->prot_length;
1312
1313         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1314                 unsigned int psg_len, copied = 0;
1315
1316                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1317                 psg_len = min(left, psg->length);
1318                 while (psg_len) {
1319                         len = min(psg_len, sg->length - offset);
1320                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1321
1322                         if (read)
1323                                 memcpy(paddr + copied, addr, len);
1324                         else
1325                                 memcpy(addr, paddr + copied, len);
1326
1327                         left -= len;
1328                         offset += len;
1329                         copied += len;
1330                         psg_len -= len;
1331
1332                         kunmap_atomic(addr - sg->offset - offset);
1333
1334                         if (offset >= sg->length) {
1335                                 sg = sg_next(sg);
1336                                 offset = 0;
1337                         }
1338                 }
1339                 kunmap_atomic(paddr - psg->offset);
1340         }
1341 }
1342 EXPORT_SYMBOL(sbc_dif_copy_prot);
1343
1344 sense_reason_t
1345 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1346                unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1347 {
1348         struct se_device *dev = cmd->se_dev;
1349         struct se_dif_v1_tuple *sdt;
1350         struct scatterlist *dsg = cmd->t_data_sg;
1351         sector_t sector = start;
1352         void *daddr, *paddr;
1353         int i;
1354         sense_reason_t rc;
1355         int dsg_off = 0;
1356         unsigned int block_size = dev->dev_attrib.block_size;
1357
1358         for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1359                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1360                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1361
1362                 for (i = psg_off; i < psg->length &&
1363                                 sector < start + sectors;
1364                                 i += sizeof(struct se_dif_v1_tuple)) {
1365                         __u16 crc;
1366                         unsigned int avail;
1367
1368                         if (dsg_off >= dsg->length) {
1369                                 dsg_off -= dsg->length;
1370                                 kunmap_atomic(daddr - dsg->offset);
1371                                 dsg = sg_next(dsg);
1372                                 if (!dsg) {
1373                                         kunmap_atomic(paddr - psg->offset);
1374                                         return 0;
1375                                 }
1376                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1377                         }
1378
1379                         sdt = paddr + i;
1380
1381                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1382                                  " app_tag: 0x%04x ref_tag: %u\n",
1383                                  (unsigned long long)sector, sdt->guard_tag,
1384                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1385
1386                         if (sdt->app_tag == cpu_to_be16(0xffff)) {
1387                                 dsg_off += block_size;
1388                                 goto next;
1389                         }
1390
1391                         avail = min(block_size, dsg->length - dsg_off);
1392                         crc = crc_t10dif(daddr + dsg_off, avail);
1393                         if (avail < block_size) {
1394                                 kunmap_atomic(daddr - dsg->offset);
1395                                 dsg = sg_next(dsg);
1396                                 if (!dsg) {
1397                                         kunmap_atomic(paddr - psg->offset);
1398                                         return 0;
1399                                 }
1400                                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1401                                 dsg_off = block_size - avail;
1402                                 crc = crc_t10dif_update(crc, daddr, dsg_off);
1403                         } else {
1404                                 dsg_off += block_size;
1405                         }
1406
1407                         rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1408                         if (rc) {
1409                                 kunmap_atomic(daddr - dsg->offset);
1410                                 kunmap_atomic(paddr - psg->offset);
1411                                 cmd->bad_sector = sector;
1412                                 return rc;
1413                         }
1414 next:
1415                         sector++;
1416                         ei_lba++;
1417                 }
1418
1419                 psg_off = 0;
1420                 kunmap_atomic(daddr - dsg->offset);
1421                 kunmap_atomic(paddr - psg->offset);
1422         }
1423
1424         return 0;
1425 }
1426 EXPORT_SYMBOL(sbc_dif_verify);