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
 372         /*
 373          * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
 374          * within target_complete_ok_work() if the command was successfully
 375          * sent to the backend driver.
 376          */
 377         spin_lock_irq(&cmd->t_state_lock);
 378         if ((cmd->transport_state & CMD_T_SENT) && !cmd->scsi_status) {
 379                 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 380                 *post_ret = 1;
 381         }
 382         spin_unlock_irq(&cmd->t_state_lock);
 383
 384         /*
 385          * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 386          * before the original READ I/O submission.
 387          */
 388         up(&dev->caw_sem);
 389
 390         return TCM_NO_SENSE;
 391 }
 392
 393 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 394                                                  int *post_ret)
 395 {
 396         struct se_device *dev = cmd->se_dev;
 397         struct scatterlist *write_sg = NULL, *sg;
 398         unsigned char *buf = NULL, *addr;
 399         struct sg_mapping_iter m;
 400         unsigned int offset = 0, len;
 401         unsigned int nlbas = cmd->t_task_nolb;
 402         unsigned int block_size = dev->dev_attrib.block_size;
 403         unsigned int compare_len = (nlbas * block_size);
 404         sense_reason_t ret = TCM_NO_SENSE;
 405         int rc, i;
 406
 407         /*
 408          * Handle early failure in transport_generic_request_failure(),
 409          * which will not have taken ->caw_sem yet..
 410          */
 411         if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
 412                 return TCM_NO_SENSE;
 413         /*
 414          * Handle special case for zero-length COMPARE_AND_WRITE
 415          */
 416         if (!cmd->data_length)
 417                 goto out;
 418         /*
 419          * Immediately exit + release dev->caw_sem if command has already
 420          * been failed with a non-zero SCSI status.
 421          */
 422         if (cmd->scsi_status) {
 423                 pr_err("compare_and_write_callback: non zero scsi_status:"
 424                         " 0x%02x\n", cmd->scsi_status);
 425                 goto out;
 426         }
 427
 428         buf = kzalloc(cmd->data_length, GFP_KERNEL);
 429         if (!buf) {
 430                 pr_err("Unable to allocate compare_and_write buf\n");
 431                 ret = TCM_OUT_OF_RESOURCES;
 432                 goto out;
 433         }
 434
 435         write_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
 436                            GFP_KERNEL);
 437         if (!write_sg) {
 438                 pr_err("Unable to allocate compare_and_write sg\n");
 439                 ret = TCM_OUT_OF_RESOURCES;
 440                 goto out;
 441         }
 442         sg_init_table(write_sg, cmd->t_data_nents);
 443         /*
 444          * Setup verify and write data payloads from total NumberLBAs.
 445          */
 446         rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 447                                cmd->data_length);
 448         if (!rc) {
 449                 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 450                 ret = TCM_OUT_OF_RESOURCES;
 451                 goto out;
 452         }
 453         /*
 454          * Compare against SCSI READ payload against verify payload
 455          */
 456         for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 457                 addr = (unsigned char *)kmap_atomic(sg_page(sg));
 458                 if (!addr) {
 459                         ret = TCM_OUT_OF_RESOURCES;
 460                         goto out;
 461                 }
 462
 463                 len = min(sg->length, compare_len);
 464
 465                 if (memcmp(addr, buf + offset, len)) {
 466                         pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 467                                 addr, buf + offset);
 468                         kunmap_atomic(addr);
 469                         goto miscompare;
 470                 }
 471                 kunmap_atomic(addr);
 472
 473                 offset += len;
 474                 compare_len -= len;
 475                 if (!compare_len)
 476                         break;
 477         }
 478
 479         i = 0;
 480         len = cmd->t_task_nolb * block_size;
 481         sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 482         /*
 483          * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 484          */
 485         while (len) {
 486                 sg_miter_next(&m);
 487
 488                 if (block_size < PAGE_SIZE) {
 489                         sg_set_page(&write_sg[i], m.page, block_size,
 490                                     m.piter.sg->offset + block_size);
 491                 } else {
 492                         sg_miter_next(&m);
 493                         sg_set_page(&write_sg[i], m.page, block_size,
 494                                     m.piter.sg->offset);
 495                 }
 496                 len -= block_size;
 497                 i++;
 498         }
 499         sg_miter_stop(&m);
 500         /*
 501          * Save the original SGL + nents values before updating to new
 502          * assignments, to be released in transport_free_pages() ->
 503          * transport_reset_sgl_orig()
 504          */
 505         cmd->t_data_sg_orig = cmd->t_data_sg;
 506         cmd->t_data_sg = write_sg;
 507         cmd->t_data_nents_orig = cmd->t_data_nents;
 508         cmd->t_data_nents = 1;
 509
 510         cmd->sam_task_attr = MSG_HEAD_TAG;
 511         cmd->transport_complete_callback = compare_and_write_post;
 512         /*
 513          * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 514          * for submitting the adjusted SGL to write instance user-data.
 515          */
 516         cmd->execute_cmd = sbc_execute_rw;
 517
 518         spin_lock_irq(&cmd->t_state_lock);
 519         cmd->t_state = TRANSPORT_PROCESSING;
 520         cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 521         spin_unlock_irq(&cmd->t_state_lock);
 522
 523         __target_execute_cmd(cmd);
 524
 525         kfree(buf);
 526         return ret;
 527
 528 miscompare:
 529         pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 530                 dev->transport->name);
 531         ret = TCM_MISCOMPARE_VERIFY;
 532 out:
 533         /*
 534          * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 535          * sbc_compare_and_write() before the original READ I/O submission.
 536          */
 537         up(&dev->caw_sem);
 538         kfree(write_sg);
 539         kfree(buf);
 540         return ret;
 541 }
 542
 543 static sense_reason_t
 544 sbc_compare_and_write(struct se_cmd *cmd)
 545 {
 546         struct se_device *dev = cmd->se_dev;
 547         sense_reason_t ret;
 548         int rc;
 549         /*
 550          * Submit the READ first for COMPARE_AND_WRITE to perform the
 551          * comparision using SGLs at cmd->t_bidi_data_sg..
 552          */
 553         rc = down_interruptible(&dev->caw_sem);
 554         if ((rc != 0) || signal_pending(current)) {
 555                 cmd->transport_complete_callback = NULL;
 556                 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 557         }
 558         /*
 559          * Reset cmd->data_length to individual block_size in order to not
 560          * confuse backend drivers that depend on this value matching the
 561          * size of the I/O being submitted.
 562          */
 563         cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 564
 565         ret = cmd->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 566                               DMA_FROM_DEVICE);
 567         if (ret) {
 568                 cmd->transport_complete_callback = NULL;
 569                 up(&dev->caw_sem);
 570                 return ret;
 571         }
 572         /*
 573          * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 574          * upon MISCOMPARE, or in compare_and_write_done() upon completion
 575          * of WRITE instance user-data.
 576          */
 577         return TCM_NO_SENSE;
 578 }
 579
 580 static int
 581 sbc_set_prot_op_checks(u8 protect, enum target_prot_type prot_type,
 582                        bool is_write, struct se_cmd *cmd)
 583 {
 584         if (is_write) {
 585                 cmd->prot_op = protect ? TARGET_PROT_DOUT_PASS :
 586                                          TARGET_PROT_DOUT_INSERT;
 587                 switch (protect) {
 588                 case 0x0:
 589                 case 0x3:
 590                         cmd->prot_checks = 0;
 591                         break;
 592                 case 0x1:
 593                 case 0x5:
 594                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 595                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 596                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 597                         break;
 598                 case 0x2:
 599                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 600                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 601                         break;
 602                 case 0x4:
 603                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 604                         break;
 605                 default:
 606                         pr_err("Unsupported protect field %d\n", protect);
 607                         return -EINVAL;
 608                 }
 609         } else {
 610                 cmd->prot_op = protect ? TARGET_PROT_DIN_PASS :
 611                                          TARGET_PROT_DIN_STRIP;
 612                 switch (protect) {
 613                 case 0x0:
 614                 case 0x1:
 615                 case 0x5:
 616                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 617                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 618                                 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 619                         break;
 620                 case 0x2:
 621                         if (prot_type == TARGET_DIF_TYPE1_PROT)
 622                                 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 623                         break;
 624                 case 0x3:
 625                         cmd->prot_checks = 0;
 626                         break;
 627                 case 0x4:
 628                         cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 629                         break;
 630                 default:
 631                         pr_err("Unsupported protect field %d\n", protect);
 632                         return -EINVAL;
 633                 }
 634         }
 635
 636         return 0;
 637 }
 638
 639 static bool
 640 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 641                u32 sectors, bool is_write)
 642 {
 643         u8 protect = cdb[1] >> 5;
 644
 645         if ((!cmd->t_prot_sg || !cmd->t_prot_nents) && cmd->prot_pto)
 646                 return true;
 647
 648         switch (dev->dev_attrib.pi_prot_type) {
 649         case TARGET_DIF_TYPE3_PROT:
 650                 cmd->reftag_seed = 0xffffffff;
 651                 break;
 652         case TARGET_DIF_TYPE2_PROT:
 653                 if (protect)
 654                         return false;
 655
 656                 cmd->reftag_seed = cmd->t_task_lba;
 657                 break;
 658         case TARGET_DIF_TYPE1_PROT:
 659                 cmd->reftag_seed = cmd->t_task_lba;
 660                 break;
 661         case TARGET_DIF_TYPE0_PROT:
 662         default:
 663                 return true;
 664         }
 665
 666         if (sbc_set_prot_op_checks(protect, dev->dev_attrib.pi_prot_type,
 667                                    is_write, cmd))
 668                 return false;
 669
 670         cmd->prot_type = dev->dev_attrib.pi_prot_type;
 671         cmd->prot_length = dev->prot_length * sectors;
 672
 673         /**
 674          * In case protection information exists over the wire
 675          * we modify command data length to describe pure data.
 676          * The actual transfer length is data length + protection
 677          * length
 678          **/
 679         if (protect)
 680                 cmd->data_length = sectors * dev->dev_attrib.block_size;
 681
 682         pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 683                  "prot_op=%d prot_checks=%d\n",
 684                  __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 685                  cmd->prot_op, cmd->prot_checks);
 686
 687         return true;
 688 }
 689
 690 sense_reason_t
 691 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 692 {
 693         struct se_device *dev = cmd->se_dev;
 694         unsigned char *cdb = cmd->t_task_cdb;
 695         unsigned int size;
 696         u32 sectors = 0;
 697         sense_reason_t ret;
 698
 699         switch (cdb[0]) {
 700         case READ_6:
 701                 sectors = transport_get_sectors_6(cdb);
 702                 cmd->t_task_lba = transport_lba_21(cdb);
 703                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 704                 cmd->execute_rw = ops->execute_rw;
 705                 cmd->execute_cmd = sbc_execute_rw;
 706                 break;
 707         case READ_10:
 708                 sectors = transport_get_sectors_10(cdb);
 709                 cmd->t_task_lba = transport_lba_32(cdb);
 710
 711                 if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 712                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 713
 714                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 715                 cmd->execute_rw = ops->execute_rw;
 716                 cmd->execute_cmd = sbc_execute_rw;
 717                 break;
 718         case READ_12:
 719                 sectors = transport_get_sectors_12(cdb);
 720                 cmd->t_task_lba = transport_lba_32(cdb);
 721
 722                 if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 723                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 724
 725                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 726                 cmd->execute_rw = ops->execute_rw;
 727                 cmd->execute_cmd = sbc_execute_rw;
 728                 break;
 729         case READ_16:
 730                 sectors = transport_get_sectors_16(cdb);
 731                 cmd->t_task_lba = transport_lba_64(cdb);
 732
 733                 if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 734                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 735
 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_6:
 741                 sectors = transport_get_sectors_6(cdb);
 742                 cmd->t_task_lba = transport_lba_21(cdb);
 743                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 744                 cmd->execute_rw = ops->execute_rw;
 745                 cmd->execute_cmd = sbc_execute_rw;
 746                 break;
 747         case WRITE_10:
 748         case WRITE_VERIFY:
 749                 sectors = transport_get_sectors_10(cdb);
 750                 cmd->t_task_lba = transport_lba_32(cdb);
 751
 752                 if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 753                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 754
 755                 if (cdb[1] & 0x8)
 756                         cmd->se_cmd_flags |= SCF_FUA;
 757                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 758                 cmd->execute_rw = ops->execute_rw;
 759                 cmd->execute_cmd = sbc_execute_rw;
 760                 break;
 761         case WRITE_12:
 762                 sectors = transport_get_sectors_12(cdb);
 763                 cmd->t_task_lba = transport_lba_32(cdb);
 764
 765                 if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 766                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 767
 768                 if (cdb[1] & 0x8)
 769                         cmd->se_cmd_flags |= SCF_FUA;
 770                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 771                 cmd->execute_rw = ops->execute_rw;
 772                 cmd->execute_cmd = sbc_execute_rw;
 773                 break;
 774         case WRITE_16:
 775                 sectors = transport_get_sectors_16(cdb);
 776                 cmd->t_task_lba = transport_lba_64(cdb);
 777
 778                 if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 779                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 780
 781                 if (cdb[1] & 0x8)
 782                         cmd->se_cmd_flags |= SCF_FUA;
 783                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 784                 cmd->execute_rw = ops->execute_rw;
 785                 cmd->execute_cmd = sbc_execute_rw;
 786                 break;
 787         case XDWRITEREAD_10:
 788                 if (cmd->data_direction != DMA_TO_DEVICE ||
 789                     !(cmd->se_cmd_flags & SCF_BIDI))
 790                         return TCM_INVALID_CDB_FIELD;
 791                 sectors = transport_get_sectors_10(cdb);
 792
 793                 cmd->t_task_lba = transport_lba_32(cdb);
 794                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 795
 796                 /*
 797                  * Setup BIDI XOR callback to be run after I/O completion.
 798                  */
 799                 cmd->execute_rw = ops->execute_rw;
 800                 cmd->execute_cmd = sbc_execute_rw;
 801                 cmd->transport_complete_callback = &xdreadwrite_callback;
 802                 if (cdb[1] & 0x8)
 803                         cmd->se_cmd_flags |= SCF_FUA;
 804                 break;
 805         case VARIABLE_LENGTH_CMD:
 806         {
 807                 u16 service_action = get_unaligned_be16(&cdb[8]);
 808                 switch (service_action) {
 809                 case XDWRITEREAD_32:
 810                         sectors = transport_get_sectors_32(cdb);
 811
 812                         /*
 813                          * Use WRITE_32 and READ_32 opcodes for the emulated
 814                          * XDWRITE_READ_32 logic.
 815                          */
 816                         cmd->t_task_lba = transport_lba_64_ext(cdb);
 817                         cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 818
 819                         /*
 820                          * Setup BIDI XOR callback to be run during after I/O
 821                          * completion.
 822                          */
 823                         cmd->execute_rw = ops->execute_rw;
 824                         cmd->execute_cmd = sbc_execute_rw;
 825                         cmd->transport_complete_callback = &xdreadwrite_callback;
 826                         if (cdb[1] & 0x8)
 827                                 cmd->se_cmd_flags |= SCF_FUA;
 828                         break;
 829                 case WRITE_SAME_32:
 830                         sectors = transport_get_sectors_32(cdb);
 831                         if (!sectors) {
 832                                 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 833                                        " supported\n");
 834                                 return TCM_INVALID_CDB_FIELD;
 835                         }
 836
 837                         size = sbc_get_size(cmd, 1);
 838                         cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 839
 840                         ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 841                         if (ret)
 842                                 return ret;
 843                         break;
 844                 default:
 845                         pr_err("VARIABLE_LENGTH_CMD service action"
 846                                 " 0x%04x not supported\n", service_action);
 847                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 848                 }
 849                 break;
 850         }
 851         case COMPARE_AND_WRITE:
 852                 sectors = cdb[13];
 853                 /*
 854                  * Currently enforce COMPARE_AND_WRITE for a single sector
 855                  */
 856                 if (sectors > 1) {
 857                         pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 858                                " than 1\n", sectors);
 859                         return TCM_INVALID_CDB_FIELD;
 860                 }
 861                 /*
 862                  * Double size because we have two buffers, note that
 863                  * zero is not an error..
 864                  */
 865                 size = 2 * sbc_get_size(cmd, sectors);
 866                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 867                 cmd->t_task_nolb = sectors;
 868                 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
 869                 cmd->execute_rw = ops->execute_rw;
 870                 cmd->execute_cmd = sbc_compare_and_write;
 871                 cmd->transport_complete_callback = compare_and_write_callback;
 872                 break;
 873         case READ_CAPACITY:
 874                 size = READ_CAP_LEN;
 875                 cmd->execute_cmd = sbc_emulate_readcapacity;
 876                 break;
 877         case SERVICE_ACTION_IN:
 878                 switch (cmd->t_task_cdb[1] & 0x1f) {
 879                 case SAI_READ_CAPACITY_16:
 880                         cmd->execute_cmd = sbc_emulate_readcapacity_16;
 881                         break;
 882                 case SAI_REPORT_REFERRALS:
 883                         cmd->execute_cmd = target_emulate_report_referrals;
 884                         break;
 885                 default:
 886                         pr_err("Unsupported SA: 0x%02x\n",
 887                                 cmd->t_task_cdb[1] & 0x1f);
 888                         return TCM_INVALID_CDB_FIELD;
 889                 }
 890                 size = (cdb[10] << 24) | (cdb[11] << 16) |
 891                        (cdb[12] << 8) | cdb[13];
 892                 break;
 893         case SYNCHRONIZE_CACHE:
 894         case SYNCHRONIZE_CACHE_16:
 895                 if (cdb[0] == SYNCHRONIZE_CACHE) {
 896                         sectors = transport_get_sectors_10(cdb);
 897                         cmd->t_task_lba = transport_lba_32(cdb);
 898                 } else {
 899                         sectors = transport_get_sectors_16(cdb);
 900                         cmd->t_task_lba = transport_lba_64(cdb);
 901                 }
 902                 if (ops->execute_sync_cache) {
 903                         cmd->execute_cmd = ops->execute_sync_cache;
 904                         goto check_lba;
 905                 }
 906                 size = 0;
 907                 cmd->execute_cmd = sbc_emulate_noop;
 908                 break;
 909         case UNMAP:
 910                 if (!ops->execute_unmap)
 911                         return TCM_UNSUPPORTED_SCSI_OPCODE;
 912
 913                 size = get_unaligned_be16(&cdb[7]);
 914                 cmd->execute_cmd = ops->execute_unmap;
 915                 break;
 916         case WRITE_SAME_16:
 917                 sectors = transport_get_sectors_16(cdb);
 918                 if (!sectors) {
 919                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 920                         return TCM_INVALID_CDB_FIELD;
 921                 }
 922
 923                 size = sbc_get_size(cmd, 1);
 924                 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 925
 926                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
 927                 if (ret)
 928                         return ret;
 929                 break;
 930         case WRITE_SAME:
 931                 sectors = transport_get_sectors_10(cdb);
 932                 if (!sectors) {
 933                         pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 934                         return TCM_INVALID_CDB_FIELD;
 935                 }
 936
 937                 size = sbc_get_size(cmd, 1);
 938                 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
 939
 940                 /*
 941                  * Follow sbcr26 with WRITE_SAME (10) and check for the existence
 942                  * of byte 1 bit 3 UNMAP instead of original reserved field
 943                  */
 944                 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
 945                 if (ret)
 946                         return ret;
 947                 break;
 948         case VERIFY:
 949         case VERIFY_16:
 950                 size = 0;
 951                 if (cdb[0] == VERIFY) {
 952                         sectors = transport_get_sectors_10(cdb);
 953                         cmd->t_task_lba = transport_lba_32(cdb);
 954                 } else {
 955                         sectors = transport_get_sectors_16(cdb);
 956                         cmd->t_task_lba = transport_lba_64(cdb);
 957                 }
 958                 cmd->execute_cmd = sbc_emulate_noop;
 959                 goto check_lba;
 960         case REZERO_UNIT:
 961         case SEEK_6:
 962         case SEEK_10:
 963                 /*
 964                  * There are still clients out there which use these old SCSI-2
 965                  * commands. This mainly happens when running VMs with legacy
 966                  * guest systems, connected via SCSI command pass-through to
 967                  * iSCSI targets. Make them happy and return status GOOD.
 968                  */
 969                 size = 0;
 970                 cmd->execute_cmd = sbc_emulate_noop;
 971                 break;
 972         default:
 973                 ret = spc_parse_cdb(cmd, &size);
 974                 if (ret)
 975                         return ret;
 976         }
 977
 978         /* reject any command that we don't have a handler for */
 979         if (!cmd->execute_cmd)
 980                 return TCM_UNSUPPORTED_SCSI_OPCODE;
 981
 982         if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
 983                 unsigned long long end_lba;
 984 check_lba:
 985                 end_lba = dev->transport->get_blocks(dev) + 1;
 986                 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 987                     ((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 void
1094 sbc_dif_generate(struct se_cmd *cmd)
1095 {
1096         struct se_device *dev = cmd->se_dev;
1097         struct se_dif_v1_tuple *sdt;
1098         struct scatterlist *dsg, *psg = cmd->t_prot_sg;
1099         sector_t sector = cmd->t_task_lba;
1100         void *daddr, *paddr;
1101         int i, j, offset = 0;
1102
1103         for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
1104                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1105                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1106
1107                 for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1108
1109                         if (offset >= psg->length) {
1110                                 kunmap_atomic(paddr);
1111                                 psg = sg_next(psg);
1112                                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1113                                 offset = 0;
1114                         }
1115
1116                         sdt = paddr + offset;
1117                         sdt->guard_tag = cpu_to_be16(crc_t10dif(daddr + j,
1118                                                 dev->dev_attrib.block_size));
1119                         if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT)
1120                                 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1121                         sdt->app_tag = 0;
1122
1123                         pr_debug("DIF WRITE INSERT sector: %llu guard_tag: 0x%04x"
1124                                  " app_tag: 0x%04x ref_tag: %u\n",
1125                                  (unsigned long long)sector, sdt->guard_tag,
1126                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1127
1128                         sector++;
1129                         offset += sizeof(struct se_dif_v1_tuple);
1130                 }
1131
1132                 kunmap_atomic(paddr);
1133                 kunmap_atomic(daddr);
1134         }
1135 }
1136
1137 static sense_reason_t
1138 sbc_dif_v1_verify(struct se_device *dev, struct se_dif_v1_tuple *sdt,
1139                   const void *p, sector_t sector, unsigned int ei_lba)
1140 {
1141         int block_size = dev->dev_attrib.block_size;
1142         __be16 csum;
1143
1144         csum = cpu_to_be16(crc_t10dif(p, block_size));
1145
1146         if (sdt->guard_tag != csum) {
1147                 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1148                         " csum 0x%04x\n", (unsigned long long)sector,
1149                         be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1150                 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1151         }
1152
1153         if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT &&
1154             be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1155                 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1156                        " sector MSB: 0x%08x\n", (unsigned long long)sector,
1157                        be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1158                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1159         }
1160
1161         if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE2_PROT &&
1162             be32_to_cpu(sdt->ref_tag) != ei_lba) {
1163                 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1164                        " ei_lba: 0x%08x\n", (unsigned long long)sector,
1165                         be32_to_cpu(sdt->ref_tag), ei_lba);
1166                 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1167         }
1168
1169         return 0;
1170 }
1171
1172 static void
1173 sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1174                   struct scatterlist *sg, int sg_off)
1175 {
1176         struct se_device *dev = cmd->se_dev;
1177         struct scatterlist *psg;
1178         void *paddr, *addr;
1179         unsigned int i, len, left;
1180         unsigned int offset = sg_off;
1181
1182         left = sectors * dev->prot_length;
1183
1184         for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1185                 unsigned int psg_len, copied = 0;
1186
1187                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1188                 psg_len = min(left, psg->length);
1189                 while (psg_len) {
1190                         len = min(psg_len, sg->length - offset);
1191                         addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1192
1193                         if (read)
1194                                 memcpy(paddr + copied, addr, len);
1195                         else
1196                                 memcpy(addr, paddr + copied, len);
1197
1198                         left -= len;
1199                         offset += len;
1200                         copied += len;
1201                         psg_len -= len;
1202
1203                         if (offset >= sg->length) {
1204                                 sg = sg_next(sg);
1205                                 offset = 0;
1206                         }
1207                         kunmap_atomic(addr);
1208                 }
1209                 kunmap_atomic(paddr);
1210         }
1211 }
1212
1213 sense_reason_t
1214 sbc_dif_verify_write(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1215                      unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1216 {
1217         struct se_device *dev = cmd->se_dev;
1218         struct se_dif_v1_tuple *sdt;
1219         struct scatterlist *dsg, *psg = cmd->t_prot_sg;
1220         sector_t sector = start;
1221         void *daddr, *paddr;
1222         int i, j, offset = 0;
1223         sense_reason_t rc;
1224
1225         for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
1226                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1227                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1228
1229                 for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1230
1231                         if (offset >= psg->length) {
1232                                 kunmap_atomic(paddr);
1233                                 psg = sg_next(psg);
1234                                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1235                                 offset = 0;
1236                         }
1237
1238                         sdt = paddr + offset;
1239
1240                         pr_debug("DIF WRITE sector: %llu guard_tag: 0x%04x"
1241                                  " app_tag: 0x%04x ref_tag: %u\n",
1242                                  (unsigned long long)sector, sdt->guard_tag,
1243                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1244
1245                         rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
1246                                                ei_lba);
1247                         if (rc) {
1248                                 kunmap_atomic(paddr);
1249                                 kunmap_atomic(daddr);
1250                                 cmd->bad_sector = sector;
1251                                 return rc;
1252                         }
1253
1254                         sector++;
1255                         ei_lba++;
1256                         offset += sizeof(struct se_dif_v1_tuple);
1257                 }
1258
1259                 kunmap_atomic(paddr);
1260                 kunmap_atomic(daddr);
1261         }
1262         sbc_dif_copy_prot(cmd, sectors, false, sg, sg_off);
1263
1264         return 0;
1265 }
1266 EXPORT_SYMBOL(sbc_dif_verify_write);
1267
1268 static sense_reason_t
1269 __sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1270                       unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1271 {
1272         struct se_device *dev = cmd->se_dev;
1273         struct se_dif_v1_tuple *sdt;
1274         struct scatterlist *dsg, *psg = sg;
1275         sector_t sector = start;
1276         void *daddr, *paddr;
1277         int i, j, offset = sg_off;
1278         sense_reason_t rc;
1279
1280         for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
1281                 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1282                 paddr = kmap_atomic(sg_page(psg)) + sg->offset;
1283
1284                 for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1285
1286                         if (offset >= psg->length) {
1287                                 kunmap_atomic(paddr);
1288                                 psg = sg_next(psg);
1289                                 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1290                                 offset = 0;
1291                         }
1292
1293                         sdt = paddr + offset;
1294
1295                         pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1296                                  " app_tag: 0x%04x ref_tag: %u\n",
1297                                  (unsigned long long)sector, sdt->guard_tag,
1298                                  sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1299
1300                         if (sdt->app_tag == cpu_to_be16(0xffff)) {
1301                                 sector++;
1302                                 offset += sizeof(struct se_dif_v1_tuple);
1303                                 continue;
1304                         }
1305
1306                         rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
1307                                                ei_lba);
1308                         if (rc) {
1309                                 kunmap_atomic(paddr);
1310                                 kunmap_atomic(daddr);
1311                                 cmd->bad_sector = sector;
1312                                 return rc;
1313                         }
1314
1315                         sector++;
1316                         ei_lba++;
1317                         offset += sizeof(struct se_dif_v1_tuple);
1318                 }
1319
1320                 kunmap_atomic(paddr);
1321                 kunmap_atomic(daddr);
1322         }
1323
1324         return 0;
1325 }
1326
1327 sense_reason_t
1328 sbc_dif_read_strip(struct se_cmd *cmd)
1329 {
1330         struct se_device *dev = cmd->se_dev;
1331         u32 sectors = cmd->prot_length / dev->prot_length;
1332
1333         return __sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0,
1334                                      cmd->t_prot_sg, 0);
1335 }
1336
1337 sense_reason_t
1338 sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1339                     unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1340 {
1341         sense_reason_t rc;
1342
1343         rc = __sbc_dif_verify_read(cmd, start, sectors, ei_lba, sg, sg_off);
1344         if (rc)
1345                 return rc;
1346
1347         sbc_dif_copy_prot(cmd, sectors, true, sg, sg_off);
1348         return 0;
1349 }
1350 EXPORT_SYMBOL(sbc_dif_verify_read);