drivers/target/target_core_sbc.c

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