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