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