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         struct se_device *dev = cmd->se_dev;
 255         sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 256         unsigned int sectors = sbc_get_write_same_sectors(cmd);
 257
 258         if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 259                 pr_err("WRITE_SAME PBDATA and LBDATA"
 260                         " bits not supported for Block Discard"
 261                         " Emulation\n");
 262                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 263         }
 264         if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 265                 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 266                         sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 267                 return TCM_INVALID_CDB_FIELD;
 268         }
 269         /*
 270          * Sanity check for LBA wrap and request past end of device.
 271          */
 272         if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 273             ((cmd->t_task_lba + sectors) > end_lba)) {
 274                 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
 275                        (unsigned long long)end_lba, cmd->t_task_lba, sectors);
 276                 return TCM_ADDRESS_OUT_OF_RANGE;
 277         }
 278
 279         /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 280         if (flags[0] & 0x10) {
 281                 pr_warn("WRITE SAME with ANCHOR not supported\n");
 282                 return TCM_INVALID_CDB_FIELD;
 283         }
 284         /*
 285          * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 286          * translated into block discard requests within backend code.
 287          */
 288         if (flags[0] & 0x08) {
 289                 if (!ops->execute_write_same_unmap)
 290                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 291
 292                 cmd->execute_cmd = ops->execute_write_same_unmap;
 293                 return 0;
 294         }
 295         if (!ops->execute_write_same)
 296                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 297
 298         cmd->execute_cmd = ops->execute_write_same;
 299         return 0;
 300 }
 301
 302 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
 303                                            int *post_ret)
 304 {
 305         unsigned char *buf, *addr;
 306         struct scatterlist *sg;
 307         unsigned int offset;
 308         sense_reason_t ret = TCM_NO_SENSE;
 309         int i, count;
 310         /*
 311          * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 312          *
 313          * 1) read the specified logical block(s);
 314          * 2) transfer logical blocks from the data-out buffer;
 315          * 3) XOR the logical blocks transferred from the data-out buffer with
 316          *    the logical blocks read, storing the resulting XOR data in a buffer;
 317          * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 318          *    blocks transferred from the data-out buffer; and
 319          * 5) transfer the resulting XOR data to the data-in buffer.
 320          */
 321         buf = kmalloc(cmd->data_length, GFP_KERNEL);
 322         if (!buf) {
 323                 pr_err("Unable to allocate xor_callback buf\n");
 324                 return TCM_OUT_OF_RESOURCES;
 325         }
 326         /*
 327          * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 328          * into the locally allocated *buf
 329          */
 330         sg_copy_to_buffer(cmd->t_data_sg,
 331                           cmd->t_data_nents,
 332                           buf,
 333                           cmd->data_length);
 334
 335         /*
 336          * Now perform the XOR against the BIDI read memory located at
 337          * cmd->t_mem_bidi_list
 338          */
 339
 340         offset = 0;
 341         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 342                 addr = kmap_atomic(sg_page(sg));
 343                 if (!addr) {
 344                         ret = TCM_OUT_OF_RESOURCES;
 345                         goto out;
 346                 }
 347
 348                 for (i = 0; i < sg->length; i++)
 349                         *(addr + sg->offset + i) ^= *(buf + offset + i);
 350
 351                 offset += sg->length;
 352                 kunmap_atomic(addr);
 353         }
 354
 355 out:
 356         kfree(buf);
 357         return ret;
 358 }
 359
 360 static sense_reason_t
 361 sbc_execute_rw(struct se_cmd *cmd)
 362 {
 363         return cmd->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 364                                cmd->data_direction);
 365 }
 366
 367 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
 368                                              int *post_ret)
 369 {
 370         struct se_device *dev = cmd->se_dev;
 371         sense_reason_t ret = TCM_NO_SENSE;
 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) {
 380                 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 381                 *post_ret = 1;
 382
 383                 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 384                         ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 385         }
 386         spin_unlock_irq(&cmd->t_state_lock);
 387
 388         /*
 389          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 390          * before the original READ I/O submission.
 391          */
 392         up(&dev->caw_sem);
 393
 394         return ret;
 395 }
 396
 397 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 398                                                  int *post_ret)
 399 {
 400         struct se_device *dev = cmd->se_dev;
 401         struct scatterlist *write_sg = NULL, *sg;
 402         unsigned char *buf = NULL, *addr;
 403         struct sg_mapping_iter m;
 404         unsigned int offset = 0, len;
 405         unsigned int nlbas = cmd->t_task_nolb;
 406         unsigned int block_size = dev->dev_attrib.block_size;
 407         unsigned int compare_len = (nlbas * block_size);
 408         sense_reason_t ret = TCM_NO_SENSE;
 409         int rc, i;
 410
 411         /*
 412          * Handle early failure in transport_generic_request_failure(),
 413          * which will not have taken ->caw_sem yet..
 414          */
 415         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 416                 return TCM_NO_SENSE;
 417         /*
 418          * Handle special case for zero-length COMPARE_AND_WRITE
 419          */
 420         if (!cmd->data_length)
 421                 goto out;
 422         /*
 423          * Immediately exit + release dev->caw_sem if command has already
 424          * been failed with a non-zero SCSI status.
 425          */
 426         if (cmd->scsi_status) {
 427                 pr_err("compare_and_write_callback: non zero scsi_status:"
 428                         " 0x%02x\n", cmd->scsi_status);
 429                 goto out;
 430         }
 431
 432         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 433         if (!buf) {
 434                 pr_err("Unable to allocate compare_and_write buf\n");
 435                 ret = TCM_OUT_OF_RESOURCES;
 436                 goto out;
 437         }
 438
 439         write_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
 440                            GFP_KERNEL);
 441         if (!write_sg) {
 442                 pr_err("Unable to allocate compare_and_write sg\n");
 443                 ret = TCM_OUT_OF_RESOURCES;
 444                 goto out;
 445         }
 446         sg_init_table(write_sg, cmd->t_data_nents);
 447         /*
 448          * Setup verify and write data payloads from total NumberLBAs.
 449          */
 450         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 451                                cmd->data_length);
 452         if (!rc) {
 453                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 454                 ret = TCM_OUT_OF_RESOURCES;
 455                 goto out;
 456         }
 457         /*
 458          * Compare against SCSI READ payload against verify payload
 459          */
 460         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 461                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 462                 if (!addr) {
 463                         ret = TCM_OUT_OF_RESOURCES;
 464                         goto out;
 465                 }
 466
 467                 len = min(sg->length, compare_len);
 468
 469                 if (memcmp(addr, buf + offset, len)) {
 470                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 471                                 addr, buf + offset);
 472                         kunmap_atomic(addr);
 473                         goto miscompare;
 474                 }
 475                 kunmap_atomic(addr);
 476
 477                 offset += len;
 478                 compare_len -= len;
 479                 if (!compare_len)
 480                         break;
 481         }
 482
 483         i = 0;
 484         len = cmd->t_task_nolb * block_size;
 485         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 486         /*
 487          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 488          */
 489         while (len) {
 490                 sg_miter_next(&m);
 491
 492                 if (block_size < PAGE_SIZE) {
 493                         sg_set_page(&write_sg[i], m.page, block_size,
 494                                     m.piter.sg->offset + block_size);
 495                 } else {
 496                         sg_miter_next(&m);
 497                         sg_set_page(&write_sg[i], m.page, block_size,
 498                                     m.piter.sg->offset);
 499                 }
 500                 len -= block_size;
 501                 i++;
 502         }
 503         sg_miter_stop(&m);
 504         /*
 505          * Save the original SGL + nents values before updating to new
 506          * assignments, to be released in transport_free_pages() ->
 507          * transport_reset_sgl_orig()
 508          */
 509         cmd->t_data_sg_orig = cmd->t_data_sg;
 510         cmd->t_data_sg = write_sg;
 511         cmd->t_data_nents_orig = cmd->t_data_nents;
 512         cmd->t_data_nents = 1;
 513
 514         cmd->sam_task_attr = MSG_HEAD_TAG;
 515         cmd->transport_complete_callback = compare_and_write_post;
 516         /*
 517          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 518          * for submitting the adjusted SGL to write instance user-data.
 519          */
 520         cmd->execute_cmd = sbc_execute_rw;
 521
 522         spin_lock_irq(&cmd->t_state_lock);
 523         cmd->t_state = TRANSPORT_PROCESSING;
 524         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 525         spin_unlock_irq(&cmd->t_state_lock);
 526
 527         __target_execute_cmd(cmd);
 528
 529         kfree(buf);
 530         return ret;
 531
 532 miscompare:
 533         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 534                 dev->transport->name);
 535         ret = TCM_MISCOMPARE_VERIFY;
 536 out:
 537         /*
 538          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 539          * sbc_compare_and_write() before the original READ I/O submission.
 540          */
 541         up(&dev->caw_sem);
 542         kfree(write_sg);
 543         kfree(buf);
 544         return ret;
 545 }
 546
 547 static sense_reason_t
 548 sbc_compare_and_write(struct se_cmd *cmd)
 549 {
 550         struct se_device *dev = cmd->se_dev;
 551         sense_reason_t ret;
 552         int rc;
 553         /*
 554          * Submit the READ first for COMPARE_AND_WRITE to perform the
 555          * comparision using SGLs at cmd->t_bidi_data_sg..
 556          */
 557         rc = down_interruptible(&dev->caw_sem);
 558         if ((rc != 0) || signal_pending(current)) {
 559                 cmd->transport_complete_callback = NULL;
 560                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 561         }
 562         /*
 563          * Reset cmd->data_length to individual block_size in order to not
 564          * confuse backend drivers that depend on this value matching the
 565          * size of the I/O being submitted.
 566          */
 567         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 568
 569         ret = cmd->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 570                               DMA_FROM_DEVICE);
 571         if (ret) {
 572                 cmd->transport_complete_callback = NULL;
 573                 up(&dev->caw_sem);
 574                 return ret;
 575         }
 576         /*
 577          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 578          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 579          * of WRITE instance user-data.
 580          */
 581         return TCM_NO_SENSE;
 582 }
 583
 584 static int
 585 sbc_set_prot_op_checks(u8 protect, enum target_prot_type prot_type,
 586                        bool is_write, struct se_cmd *cmd)
 587 {
 588         if (is_write) {
 589                 cmd->prot_op = protect ? TARGET_PROT_DOUT_PASS :
 590                                          TARGET_PROT_DOUT_INSERT;
 591                 switch (protect) {
 592                 case 0x0:
 593                 case 0x3:
 594                         cmd->prot_checks = 0;
 595                         break;
 596                 case 0x1:
 597                 case 0x5:
 598                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 599                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 600                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 601                         break;
 602                 case 0x2:
 603                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 604                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 605                         break;
 606                 case 0x4:
 607                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 608                         break;
 609                 default:
 610                         pr_err("Unsupported protect field %d\n", protect);
 611                         return -EINVAL;
 612                 }
 613         } else {
 614                 cmd->prot_op = protect ? TARGET_PROT_DIN_PASS :
 615                                          TARGET_PROT_DIN_STRIP;
 616                 switch (protect) {
 617                 case 0x0:
 618                 case 0x1:
 619                 case 0x5:
 620                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 621                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 622                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 623                         break;
 624                 case 0x2:
 625                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 626                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 627                         break;
 628                 case 0x3:
 629                         cmd->prot_checks = 0;
 630                         break;
 631                 case 0x4:
 632                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 633                         break;
 634                 default:
 635                         pr_err("Unsupported protect field %d\n", protect);
 636                         return -EINVAL;
 637                 }
 638         }
 639
 640         return 0;
 641 }
 642
 643 static bool
 644 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 645                u32 sectors, bool is_write)
 646 {
 647         u8 protect = cdb[1] >> 5;
 648
 649         if ((!cmd->t_prot_sg || !cmd->t_prot_nents) && cmd->prot_pto)
 650                 return true;
 651
 652         switch (dev->dev_attrib.pi_prot_type) {
 653         case TARGET_DIF_TYPE3_PROT:
 654                 cmd->reftag_seed = 0xffffffff;
 655                 break;
 656         case TARGET_DIF_TYPE2_PROT:
 657                 if (protect)
 658                         return false;
 659
 660                 cmd->reftag_seed = cmd->t_task_lba;
 661                 break;
 662         case TARGET_DIF_TYPE1_PROT:
 663                 cmd->reftag_seed = cmd->t_task_lba;
 664                 break;
 665         case TARGET_DIF_TYPE0_PROT:
 666         default:
 667                 return true;
 668         }
 669
 670         if (sbc_set_prot_op_checks(protect, dev->dev_attrib.pi_prot_type,
 671                                    is_write, cmd))
 672                 return false;
 673
 674         cmd->prot_type = dev->dev_attrib.pi_prot_type;
 675         cmd->prot_length = dev->prot_length * sectors;
 676
 677         /**
 678          * In case protection information exists over the wire
 679          * we modify command data length to describe pure data.
 680          * The actual transfer length is data length + protection
 681          * length
 682          **/
 683         if (protect)
 684                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 685
 686         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 687                  "prot_op=%d prot_checks=%d\n",
 688                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 689                  cmd->prot_op, cmd->prot_checks);
 690
 691         return true;
 692 }
 693
 694 sense_reason_t
 695 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 696 {
 697         struct se_device *dev = cmd->se_dev;
 698         unsigned char *cdb = cmd->t_task_cdb;
 699         unsigned int size;
 700         u32 sectors = 0;
 701         sense_reason_t ret;
 702
 703         switch (cdb[0]) {
 704         case READ_6:
 705                 sectors = transport_get_sectors_6(cdb);
 706                 cmd->t_task_lba = transport_lba_21(cdb);
 707                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 708                 cmd->execute_rw = ops->execute_rw;
 709                 cmd->execute_cmd = sbc_execute_rw;
 710                 break;
 711         case READ_10:
 712                 sectors = transport_get_sectors_10(cdb);
 713                 cmd->t_task_lba = transport_lba_32(cdb);
 714
 715                 if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 716                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 717
 718                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 719                 cmd->execute_rw = ops->execute_rw;
 720                 cmd->execute_cmd = sbc_execute_rw;
 721                 break;
 722         case READ_12:
 723                 sectors = transport_get_sectors_12(cdb);
 724                 cmd->t_task_lba = transport_lba_32(cdb);
 725
 726                 if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 727                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 728
 729                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 730                 cmd->execute_rw = ops->execute_rw;
 731                 cmd->execute_cmd = sbc_execute_rw;
 732                 break;
 733         case READ_16:
 734                 sectors = transport_get_sectors_16(cdb);
 735                 cmd->t_task_lba = transport_lba_64(cdb);
 736
 737                 if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 738                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 739
 740                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 741                 cmd->execute_rw = ops->execute_rw;
 742                 cmd->execute_cmd = sbc_execute_rw;
 743                 break;
 744         case WRITE_6:
 745                 sectors = transport_get_sectors_6(cdb);
 746                 cmd->t_task_lba = transport_lba_21(cdb);
 747                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 748                 cmd->execute_rw = ops->execute_rw;
 749                 cmd->execute_cmd = sbc_execute_rw;
 750                 break;
 751         case WRITE_10:
 752         case WRITE_VERIFY:
 753                 sectors = transport_get_sectors_10(cdb);
 754                 cmd->t_task_lba = transport_lba_32(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 WRITE_12:
 766                 sectors = transport_get_sectors_12(cdb);
 767                 cmd->t_task_lba = transport_lba_32(cdb);
 768
 769                 if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 770                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 771
 772                 if (cdb[1] & 0x8)
 773                         cmd->se_cmd_flags |= SCF_FUA;
 774                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 775                 cmd->execute_rw = ops->execute_rw;
 776                 cmd->execute_cmd = sbc_execute_rw;
 777                 break;
 778         case WRITE_16:
 779                 sectors = transport_get_sectors_16(cdb);
 780                 cmd->t_task_lba = transport_lba_64(cdb);
 781
 782                 if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 783                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 784
 785                 if (cdb[1] & 0x8)
 786                         cmd->se_cmd_flags |= SCF_FUA;
 787                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 788                 cmd->execute_rw = ops->execute_rw;
 789                 cmd->execute_cmd = sbc_execute_rw;
 790                 break;
 791         case XDWRITEREAD_10:
 792                 if (cmd->data_direction != DMA_TO_DEVICE ||
 793                     !(cmd->se_cmd_flags & SCF_BIDI))
 794                         return TCM_INVALID_CDB_FIELD;
 795                 sectors = transport_get_sectors_10(cdb);
 796
 797                 cmd->t_task_lba = transport_lba_32(cdb);
 798                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 799
 800                 /*
 801                  * Setup BIDI XOR callback to be run after I/O completion.
 802                  */
 803                 cmd->execute_rw = ops->execute_rw;
 804                 cmd->execute_cmd = sbc_execute_rw;
 805                 cmd->transport_complete_callback = &xdreadwrite_callback;
 806                 if (cdb[1] & 0x8)
 807                         cmd->se_cmd_flags |= SCF_FUA;
 808                 break;
 809         case VARIABLE_LENGTH_CMD:
 810         {
 811                 u16 service_action = get_unaligned_be16(&cdb[8]);
 812                 switch (service_action) {
 813                 case XDWRITEREAD_32:
 814                         sectors = transport_get_sectors_32(cdb);
 815
 816                         /*
 817                          * Use WRITE_32 and READ_32 opcodes for the emulated
 818                          * XDWRITE_READ_32 logic.
 819                          */
 820                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 821                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 822
 823                         /*
 824                          * Setup BIDI XOR callback to be run during after I/O
 825                          * completion.
 826                          */
 827                         cmd->execute_rw = ops->execute_rw;
 828                         cmd->execute_cmd = sbc_execute_rw;
 829                         cmd->transport_complete_callback = &xdreadwrite_callback;
 830                         if (cdb[1] & 0x8)
 831                                 cmd->se_cmd_flags |= SCF_FUA;
 832                         break;
 833                 case WRITE_SAME_32:
 834                         sectors = transport_get_sectors_32(cdb);
 835                         if (!sectors) {
 836                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 837                                        " supported\n");
 838                                 return TCM_INVALID_CDB_FIELD;
 839                         }
 840
 841                         size = sbc_get_size(cmd, 1);
 842                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 843
 844                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 845                         if (ret)
 846                                 return ret;
 847                         break;
 848                 default:
 849                         pr_err("VARIABLE_LENGTH_CMD service action"
 850                                 " 0x%04x not supported\n", service_action);
 851                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 852                 }
 853                 break;
 854         }
 855         case COMPARE_AND_WRITE:
 856                 sectors = cdb[13];
 857                 /*
 858                  * Currently enforce COMPARE_AND_WRITE for a single sector
 859                  */
 860                 if (sectors > 1) {
 861                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 862                                " than 1\n", sectors);
 863                         return TCM_INVALID_CDB_FIELD;
 864                 }
 865                 /*
 866                  * Double size because we have two buffers, note that
 867                  * zero is not an error..
 868                  */
 869                 size = 2 * sbc_get_size(cmd, sectors);
 870                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 871                 cmd->t_task_nolb = sectors;
 872                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
 873                 cmd->execute_rw = ops->execute_rw;
 874                 cmd->execute_cmd = sbc_compare_and_write;
 875                 cmd->transport_complete_callback = compare_and_write_callback;
 876                 break;
 877         case READ_CAPACITY:
 878                 size = READ_CAP_LEN;
 879                 cmd->execute_cmd = sbc_emulate_readcapacity;
 880                 break;
 881         case SERVICE_ACTION_IN:
 882                 switch (cmd->t_task_cdb[1] & 0x1f) {
 883                 case SAI_READ_CAPACITY_16:
 884                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
 885                         break;
 886                 case SAI_REPORT_REFERRALS:
 887                         cmd->execute_cmd = target_emulate_report_referrals;
 888                         break;
 889                 default:
 890                         pr_err("Unsupported SA: 0x%02x\n",
 891                                 cmd->t_task_cdb[1] & 0x1f);
 892                         return TCM_INVALID_CDB_FIELD;
 893                 }
 894                 size = (cdb[10] << 24) | (cdb[11] << 16) |
 895                        (cdb[12] << 8) | cdb[13];
 896                 break;
 897         case SYNCHRONIZE_CACHE:
 898         case SYNCHRONIZE_CACHE_16:
 899                 if (cdb[0] == SYNCHRONIZE_CACHE) {
 900                         sectors = transport_get_sectors_10(cdb);
 901                         cmd->t_task_lba = transport_lba_32(cdb);
 902                 } else {
 903                         sectors = transport_get_sectors_16(cdb);
 904                         cmd->t_task_lba = transport_lba_64(cdb);
 905                 }
 906                 if (ops->execute_sync_cache) {
 907                         cmd->execute_cmd = ops->execute_sync_cache;
 908                         goto check_lba;
 909                 }
 910                 size = 0;
 911                 cmd->execute_cmd = sbc_emulate_noop;
 912                 break;
 913         case UNMAP:
 914                 if (!ops->execute_unmap)
 915                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 916
 917                 size = get_unaligned_be16(&cdb[7]);
 918                 cmd->execute_cmd = ops->execute_unmap;
 919                 break;
 920         case WRITE_SAME_16:
 921                 sectors = transport_get_sectors_16(cdb);
 922                 if (!sectors) {
 923                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 924                         return TCM_INVALID_CDB_FIELD;
 925                 }
 926
 927                 size = sbc_get_size(cmd, 1);
 928                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 929
 930                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
 931                 if (ret)
 932                         return ret;
 933                 break;
 934         case WRITE_SAME:
 935                 sectors = transport_get_sectors_10(cdb);
 936                 if (!sectors) {
 937                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 938                         return TCM_INVALID_CDB_FIELD;
 939                 }
 940
 941                 size = sbc_get_size(cmd, 1);
 942                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
 943
 944                 /*
 945                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
 946                  * of byte 1 bit 3 UNMAP instead of original reserved field
 947                  */
 948                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
 949                 if (ret)
 950                         return ret;
 951                 break;
 952         case VERIFY:
 953         case VERIFY_16:
 954                 size = 0;
 955                 if (cdb[0] == VERIFY) {
 956                         sectors = transport_get_sectors_10(cdb);
 957                         cmd->t_task_lba = transport_lba_32(cdb);
 958                 } else {
 959                         sectors = transport_get_sectors_16(cdb);
 960                         cmd->t_task_lba = transport_lba_64(cdb);
 961                 }
 962                 cmd->execute_cmd = sbc_emulate_noop;
 963                 goto check_lba;
 964         case REZERO_UNIT:
 965         case SEEK_6:
 966         case SEEK_10:
 967                 /*
 968                  * There are still clients out there which use these old SCSI-2
 969                  * commands. This mainly happens when running VMs with legacy
 970                  * guest systems, connected via SCSI command pass-through to
 971                  * iSCSI targets. Make them happy and return status GOOD.
 972                  */
 973                 size = 0;
 974                 cmd->execute_cmd = sbc_emulate_noop;
 975                 break;
 976         default:
 977                 ret = spc_parse_cdb(cmd, &size);
 978                 if (ret)
 979                         return ret;
 980         }
 981
 982         /* reject any command that we don't have a handler for */
 983         if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
 984                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 985
 986         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
 987                 unsigned long long end_lba;
 988 check_lba:
 989                 end_lba = dev->transport->get_blocks(dev) + 1;
 990                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 991                     ((cmd->t_task_lba + sectors) > end_lba)) {
 992                         pr_err("cmd exceeds last lba %llu "
 993                                 "(lba %llu, sectors %u)\n",
 994                                 end_lba, cmd->t_task_lba, sectors);
 995                         return TCM_ADDRESS_OUT_OF_RANGE;
 996                 }
 997
 998                 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
 999                         size = sbc_get_size(cmd, sectors);
1000         }
1001
1002         return target_cmd_size_check(cmd, size);
1003 }
1004 EXPORT_SYMBOL(sbc_parse_cdb);
1005
1006 u32 sbc_get_device_type(struct se_device *dev)
1007 {
1008         return TYPE_DISK;
1009 }
1010 EXPORT_SYMBOL(sbc_get_device_type);
1011
1012 sense_reason_t
1013 sbc_execute_unmap(struct se_cmd *cmd,
1014         sense_reason_t (*do_unmap_fn)(struct se_cmd *, void *,
1015                                       sector_t, sector_t),
1016         void *priv)
1017 {
1018         struct se_device *dev = cmd->se_dev;
1019         unsigned char *buf, *ptr = NULL;
1020         sector_t lba;
1021         int size;
1022         u32 range;
1023         sense_reason_t ret = 0;
1024         int dl, bd_dl;
1025
1026         /* We never set ANC_SUP */
1027         if (cmd->t_task_cdb[1])
1028                 return TCM_INVALID_CDB_FIELD;
1029
1030         if (cmd->data_length == 0) {
1031                 target_complete_cmd(cmd, SAM_STAT_GOOD);
1032                 return 0;
1033         }
1034
1035         if (cmd->data_length < 8) {
1036                 pr_warn("UNMAP parameter list length %u too small\n",
1037                         cmd->data_length);
1038                 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1039         }
1040
1041         buf = transport_kmap_data_sg(cmd);
1042         if (!buf)
1043                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1044
1045         dl = get_unaligned_be16(&buf[0]);
1046         bd_dl = get_unaligned_be16(&buf[2]);
1047
1048         size = cmd->data_length - 8;
1049         if (bd_dl > size)
1050                 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1051                         cmd->data_length, bd_dl);
1052         else
1053                 size = bd_dl;
1054
1055         if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1056                 ret = TCM_INVALID_PARAMETER_LIST;
1057                 goto err;
1058         }
1059
1060         /* First UNMAP block descriptor starts at 8 byte offset */
1061         ptr = &buf[8];
1062         pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1063                 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1064
1065         while (size >= 16) {
1066                 lba = get_unaligned_be64(&ptr[0]);
1067                 range = get_unaligned_be32(&ptr[8]);
1068                 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1069                                  (unsigned long long)lba, range);
1070
1071                 if (range > dev->dev_attrib.max_unmap_lba_count) {
1072                         ret = TCM_INVALID_PARAMETER_LIST;
1073                         goto err;
1074                 }
1075
1076                 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1077                         ret = TCM_ADDRESS_OUT_OF_RANGE;
1078                         goto err;
1079                 }
1080
1081                 ret = do_unmap_fn(cmd, priv, lba, range);
1082                 if (ret)
1083                         goto err;
1084
1085                 ptr += 16;
1086                 size -= 16;
1087         }
1088
1089 err:
1090         transport_kunmap_data_sg(cmd);
1091         if (!ret)
1092                 target_complete_cmd(cmd, GOOD);
1093         return ret;
1094 }
1095 EXPORT_SYMBOL(sbc_execute_unmap);
1096
1097 void
1098 sbc_dif_generate(struct se_cmd *cmd)
1099 {
1100         struct se_device *dev = cmd->se_dev;
1101         struct se_dif_v1_tuple *sdt;
1102         struct scatterlist *dsg, *psg = cmd->t_prot_sg;
1103         sector_t sector = cmd->t_task_lba;
1104         void *daddr, *paddr;
1105         int i, j, offset = 0;
1106
1107         for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
1108                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1109                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1110
1111                 for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1112
1113                         if (offset >= psg->length) {
1114                                 kunmap_atomic(paddr);
1115                                 psg = sg_next(psg);
1116                                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1117                                 offset = 0;
1118                         }
1119
1120                         sdt = paddr + offset;
1121                         sdt->guard_tag = cpu_to_be16(crc_t10dif(daddr + j,
1122                                                 dev->dev_attrib.block_size));
1123                         if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT)
1124                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1125                         sdt->app_tag = 0;
1126
1127                         pr_debug("DIF WRITE INSERT sector: %llu guard_tag: 0x%04x"
1128                                  " app_tag: 0x%04x ref_tag: %u\n",
1129                                  (unsigned long long)sector, sdt->guard_tag,
1130                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1131
1132                         sector++;
1133                         offset += sizeof(struct se_dif_v1_tuple);
1134                 }
1135
1136                 kunmap_atomic(paddr);
1137                 kunmap_atomic(daddr);
1138         }
1139 }
1140
1141 static sense_reason_t
1142 sbc_dif_v1_verify(struct se_device *dev, struct se_dif_v1_tuple *sdt,
1143                   const void *p, sector_t sector, unsigned int ei_lba)
1144 {
1145         int block_size = dev->dev_attrib.block_size;
1146         __be16 csum;
1147
1148         csum = cpu_to_be16(crc_t10dif(p, block_size));
1149
1150         if (sdt->guard_tag != csum) {
1151                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1152                         " csum 0x%04x\n", (unsigned long long)sector,
1153                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1154                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1155         }
1156
1157         if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT &&
1158             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1159                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1160                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1161                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1162                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1163         }
1164
1165         if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE2_PROT &&
1166             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1167                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1168                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1169                         be32_to_cpu(sdt->ref_tag), ei_lba);
1170                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1171         }
1172
1173         return 0;
1174 }
1175
1176 static void
1177 sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1178                   struct scatterlist *sg, int sg_off)
1179 {
1180         struct se_device *dev = cmd->se_dev;
1181         struct scatterlist *psg;
1182         void *paddr, *addr;
1183         unsigned int i, len, left;
1184         unsigned int offset = sg_off;
1185
1186         left = sectors * dev->prot_length;
1187
1188         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1189                 unsigned int psg_len, copied = 0;
1190
1191                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1192                 psg_len = min(left, psg->length);
1193                 while (psg_len) {
1194                         len = min(psg_len, sg->length - offset);
1195                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1196
1197                         if (read)
1198                                 memcpy(paddr + copied, addr, len);
1199                         else
1200                                 memcpy(addr, paddr + copied, len);
1201
1202                         left -= len;
1203                         offset += len;
1204                         copied += len;
1205                         psg_len -= len;
1206
1207                         if (offset >= sg->length) {
1208                                 sg = sg_next(sg);
1209                                 offset = 0;
1210                         }
1211                         kunmap_atomic(addr);
1212                 }
1213                 kunmap_atomic(paddr);
1214         }
1215 }
1216
1217 sense_reason_t
1218 sbc_dif_verify_write(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1219                      unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1220 {
1221         struct se_device *dev = cmd->se_dev;
1222         struct se_dif_v1_tuple *sdt;
1223         struct scatterlist *dsg, *psg = cmd->t_prot_sg;
1224         sector_t sector = start;
1225         void *daddr, *paddr;
1226         int i, j, offset = 0;
1227         sense_reason_t rc;
1228
1229         for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
1230                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1231                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1232
1233                 for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1234
1235                         if (offset >= psg->length) {
1236                                 kunmap_atomic(paddr);
1237                                 psg = sg_next(psg);
1238                                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1239                                 offset = 0;
1240                         }
1241
1242                         sdt = paddr + offset;
1243
1244                         pr_debug("DIF WRITE sector: %llu guard_tag: 0x%04x"
1245                                  " app_tag: 0x%04x ref_tag: %u\n",
1246                                  (unsigned long long)sector, sdt->guard_tag,
1247                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1248
1249                         rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
1250                                                ei_lba);
1251                         if (rc) {
1252                                 kunmap_atomic(paddr);
1253                                 kunmap_atomic(daddr);
1254                                 cmd->bad_sector = sector;
1255                                 return rc;
1256                         }
1257
1258                         sector++;
1259                         ei_lba++;
1260                         offset += sizeof(struct se_dif_v1_tuple);
1261                 }
1262
1263                 kunmap_atomic(paddr);
1264                 kunmap_atomic(daddr);
1265         }
1266         sbc_dif_copy_prot(cmd, sectors, false, sg, sg_off);
1267
1268         return 0;
1269 }
1270 EXPORT_SYMBOL(sbc_dif_verify_write);
1271
1272 static sense_reason_t
1273 __sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1274                       unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1275 {
1276         struct se_device *dev = cmd->se_dev;
1277         struct se_dif_v1_tuple *sdt;
1278         struct scatterlist *dsg, *psg = sg;
1279         sector_t sector = start;
1280         void *daddr, *paddr;
1281         int i, j, offset = sg_off;
1282         sense_reason_t rc;
1283
1284         for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
1285                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1286                 paddr = kmap_atomic(sg_page(psg)) + sg->offset;
1287
1288                 for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1289
1290                         if (offset >= psg->length) {
1291                                 kunmap_atomic(paddr);
1292                                 psg = sg_next(psg);
1293                                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1294                                 offset = 0;
1295                         }
1296
1297                         sdt = paddr + offset;
1298
1299                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1300                                  " app_tag: 0x%04x ref_tag: %u\n",
1301                                  (unsigned long long)sector, sdt->guard_tag,
1302                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1303
1304                         if (sdt->app_tag == cpu_to_be16(0xffff)) {
1305                                 sector++;
1306                                 offset += sizeof(struct se_dif_v1_tuple);
1307                                 continue;
1308                         }
1309
1310                         rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
1311                                                ei_lba);
1312                         if (rc) {
1313                                 kunmap_atomic(paddr);
1314                                 kunmap_atomic(daddr);
1315                                 cmd->bad_sector = sector;
1316                                 return rc;
1317                         }
1318
1319                         sector++;
1320                         ei_lba++;
1321                         offset += sizeof(struct se_dif_v1_tuple);
1322                 }
1323
1324                 kunmap_atomic(paddr);
1325                 kunmap_atomic(daddr);
1326         }
1327
1328         return 0;
1329 }
1330
1331 sense_reason_t
1332 sbc_dif_read_strip(struct se_cmd *cmd)
1333 {
1334         struct se_device *dev = cmd->se_dev;
1335         u32 sectors = cmd->prot_length / dev->prot_length;
1336
1337         return __sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0,
1338                                      cmd->t_prot_sg, 0);
1339 }
1340
1341 sense_reason_t
1342 sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1343                     unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1344 {
1345         sense_reason_t rc;
1346
1347         rc = __sbc_dif_verify_read(cmd, start, sectors, ei_lba, sg, sg_off);
1348         if (rc)
1349                 return rc;
1350
1351         sbc_dif_copy_prot(cmd, sectors, true, sg, sg_off);
1352         return 0;
1353 }
1354 EXPORT_SYMBOL(sbc_dif_verify_read);