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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * SCSI Block Commands (SBC) parsing and emulation.
   4 *
   5 * (c) Copyright 2002-2013 Datera, Inc.
   6 *
   7 * Nicholas A. Bellinger <nab@kernel.org>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/module.h>
  12#include <linux/ratelimit.h>
  13#include <linux/crc-t10dif.h>
  14#include <linux/t10-pi.h>
  15#include <linux/unaligned.h>
  16#include <scsi/scsi_proto.h>
  17#include <scsi/scsi_tcq.h>
  18
  19#include <target/target_core_base.h>
  20#include <target/target_core_backend.h>
  21#include <target/target_core_fabric.h>
  22
  23#include "target_core_internal.h"
  24#include "target_core_ua.h"
  25#include "target_core_alua.h"
  26
  27static sense_reason_t
  28sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char, u32, bool);
  29static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
  30
  31static sense_reason_t
  32sbc_emulate_readcapacity(struct se_cmd *cmd)
  33{
  34	struct se_device *dev = cmd->se_dev;
  35	unsigned char *cdb = cmd->t_task_cdb;
  36	unsigned long long blocks_long = dev->transport->get_blocks(dev);
  37	unsigned char *rbuf;
  38	unsigned char buf[8];
  39	u32 blocks;
  40
  41	/*
  42	 * SBC-2 says:
  43	 *   If the PMI bit is set to zero and the LOGICAL BLOCK
  44	 *   ADDRESS field is not set to zero, the device server shall
  45	 *   terminate the command with CHECK CONDITION status with
  46	 *   the sense key set to ILLEGAL REQUEST and the additional
  47	 *   sense code set to INVALID FIELD IN CDB.
  48	 *
  49	 * In SBC-3, these fields are obsolete, but some SCSI
  50	 * compliance tests actually check this, so we might as well
  51	 * follow SBC-2.
  52	 */
  53	if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
  54		return TCM_INVALID_CDB_FIELD;
  55
  56	if (blocks_long >= 0x00000000ffffffff)
  57		blocks = 0xffffffff;
  58	else
  59		blocks = (u32)blocks_long;
  60
  61	put_unaligned_be32(blocks, &buf[0]);
  62	put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
 
 
 
 
 
 
  63
  64	rbuf = transport_kmap_data_sg(cmd);
  65	if (rbuf) {
  66		memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
  67		transport_kunmap_data_sg(cmd);
  68	}
  69
  70	target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, 8);
  71	return 0;
  72}
  73
  74static sense_reason_t
  75sbc_emulate_readcapacity_16(struct se_cmd *cmd)
  76{
  77	struct se_device *dev = cmd->se_dev;
  78	struct se_session *sess = cmd->se_sess;
  79	int pi_prot_type = dev->dev_attrib.pi_prot_type;
  80
  81	unsigned char *rbuf;
  82	unsigned char buf[32];
  83	unsigned long long blocks = dev->transport->get_blocks(dev);
  84
  85	memset(buf, 0, sizeof(buf));
  86	put_unaligned_be64(blocks, &buf[0]);
  87	put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
 
 
 
 
 
 
 
 
 
 
  88	/*
  89	 * Set P_TYPE and PROT_EN bits for DIF support
  90	 */
  91	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
  92		/*
  93		 * Only override a device's pi_prot_type if no T10-PI is
  94		 * available, and sess_prot_type has been explicitly enabled.
  95		 */
  96		if (!pi_prot_type)
  97			pi_prot_type = sess->sess_prot_type;
  98
  99		if (pi_prot_type)
 100			buf[12] = (pi_prot_type - 1) << 1 | 0x1;
 101	}
 102
 103	if (dev->transport->get_lbppbe)
 104		buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
 105
 106	if (dev->transport->get_alignment_offset_lbas) {
 107		u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
 108
 109		put_unaligned_be16(lalba, &buf[14]);
 110	}
 111
 112	/*
 113	 * Set Thin Provisioning Enable bit following sbc3r22 in section
 114	 * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
 115	 */
 116	if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
 117		buf[14] |= 0x80;
 118
 119		/*
 120		 * LBPRZ signifies that zeroes will be read back from an LBA after
 121		 * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2)
 122		 */
 123		if (dev->dev_attrib.unmap_zeroes_data)
 124			buf[14] |= 0x40;
 125	}
 126
 127	rbuf = transport_kmap_data_sg(cmd);
 128	if (rbuf) {
 129		memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
 130		transport_kunmap_data_sg(cmd);
 131	}
 132
 133	target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, 32);
 134	return 0;
 135}
 136
 137static sense_reason_t
 138sbc_emulate_startstop(struct se_cmd *cmd)
 139{
 140	unsigned char *cdb = cmd->t_task_cdb;
 141
 142	/*
 143	 * See sbc3r36 section 5.25
 144	 * Immediate bit should be set since there is nothing to complete
 145	 * POWER CONDITION MODIFIER 0h
 146	 */
 147	if (!(cdb[1] & 1) || cdb[2] || cdb[3])
 148		return TCM_INVALID_CDB_FIELD;
 149
 150	/*
 151	 * See sbc3r36 section 5.25
 152	 * POWER CONDITION 0h START_VALID - process START and LOEJ
 153	 */
 154	if (cdb[4] >> 4 & 0xf)
 155		return TCM_INVALID_CDB_FIELD;
 156
 157	/*
 158	 * See sbc3r36 section 5.25
 159	 * LOEJ 0h - nothing to load or unload
 160	 * START 1h - we are ready
 161	 */
 162	if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
 163		return TCM_INVALID_CDB_FIELD;
 164
 165	target_complete_cmd(cmd, SAM_STAT_GOOD);
 166	return 0;
 167}
 168
 169sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
 170{
 171	u32 num_blocks;
 172
 173	if (cmd->t_task_cdb[0] == WRITE_SAME)
 174		num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
 175	else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
 176		num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
 177	else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
 178		num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
 179
 180	/*
 181	 * Use the explicit range when non zero is supplied, otherwise calculate
 182	 * the remaining range based on ->get_blocks() - starting LBA.
 183	 */
 184	if (num_blocks)
 185		return num_blocks;
 186
 187	return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
 188		cmd->t_task_lba + 1;
 189}
 190EXPORT_SYMBOL(sbc_get_write_same_sectors);
 191
 192static sense_reason_t
 193sbc_execute_write_same_unmap(struct se_cmd *cmd)
 194{
 195	struct exec_cmd_ops *ops = cmd->protocol_data;
 196	sector_t nolb = sbc_get_write_same_sectors(cmd);
 197	sense_reason_t ret;
 198
 199	if (nolb) {
 200		ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
 201		if (ret)
 202			return ret;
 203	}
 204
 205	target_complete_cmd(cmd, SAM_STAT_GOOD);
 206	return 0;
 207}
 208
 209static sense_reason_t
 210sbc_emulate_noop(struct se_cmd *cmd)
 211{
 212	target_complete_cmd(cmd, SAM_STAT_GOOD);
 213	return 0;
 214}
 215
 216static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 217{
 218	return cmd->se_dev->dev_attrib.block_size * sectors;
 219}
 220
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 221static inline u32 transport_get_sectors_6(unsigned char *cdb)
 222{
 223	/*
 224	 * Use 8-bit sector value.  SBC-3 says:
 225	 *
 226	 *   A TRANSFER LENGTH field set to zero specifies that 256
 227	 *   logical blocks shall be written.  Any other value
 228	 *   specifies the number of logical blocks that shall be
 229	 *   written.
 230	 */
 231	return cdb[4] ? : 256;
 232}
 233
 234static inline u32 transport_get_sectors_10(unsigned char *cdb)
 235{
 236	return get_unaligned_be16(&cdb[7]);
 237}
 238
 239static inline u32 transport_get_sectors_12(unsigned char *cdb)
 240{
 241	return get_unaligned_be32(&cdb[6]);
 242}
 243
 244static inline u32 transport_get_sectors_16(unsigned char *cdb)
 245{
 246	return get_unaligned_be32(&cdb[10]);
 
 247}
 248
 249/*
 250 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 251 */
 252static inline u32 transport_get_sectors_32(unsigned char *cdb)
 253{
 254	return get_unaligned_be32(&cdb[28]);
 
 255
 256}
 257
 258static inline u32 transport_lba_21(unsigned char *cdb)
 259{
 260	return get_unaligned_be24(&cdb[1]) & 0x1fffff;
 261}
 262
 263static inline u32 transport_lba_32(unsigned char *cdb)
 264{
 265	return get_unaligned_be32(&cdb[2]);
 266}
 267
 268static inline unsigned long long transport_lba_64(unsigned char *cdb)
 269{
 270	return get_unaligned_be64(&cdb[2]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 271}
 272
 273static sense_reason_t
 274sbc_setup_write_same(struct se_cmd *cmd, unsigned char flags,
 275		     struct exec_cmd_ops *ops)
 276{
 277	struct se_device *dev = cmd->se_dev;
 278	sector_t end_lba = dev->transport->get_blocks(dev) + 1;
 279	unsigned int sectors = sbc_get_write_same_sectors(cmd);
 280	sense_reason_t ret;
 281
 282	if ((flags & 0x04) || (flags & 0x02)) {
 283		pr_err("WRITE_SAME PBDATA and LBDATA"
 284			" bits not supported for Block Discard"
 285			" Emulation\n");
 286		return TCM_UNSUPPORTED_SCSI_OPCODE;
 287	}
 288	if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 289		pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 290			sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 291		return TCM_INVALID_CDB_FIELD;
 292	}
 293	/*
 294	 * Sanity check for LBA wrap and request past end of device.
 295	 */
 296	if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
 297	    ((cmd->t_task_lba + sectors) > end_lba)) {
 298		pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
 299		       (unsigned long long)end_lba, cmd->t_task_lba, sectors);
 300		return TCM_ADDRESS_OUT_OF_RANGE;
 301	}
 302
 303	/* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 304	if (flags & 0x10) {
 305		pr_warn("WRITE SAME with ANCHOR not supported\n");
 306		return TCM_INVALID_CDB_FIELD;
 307	}
 308
 309	if (flags & 0x01) {
 310		pr_warn("WRITE SAME with NDOB not supported\n");
 311		return TCM_INVALID_CDB_FIELD;
 312	}
 313
 314	/*
 315	 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 316	 * translated into block discard requests within backend code.
 317	 */
 318	if (flags & 0x08) {
 319		if (!ops->execute_unmap)
 320			return TCM_UNSUPPORTED_SCSI_OPCODE;
 321
 322		if (!dev->dev_attrib.emulate_tpws) {
 323			pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
 324			       " has emulate_tpws disabled\n");
 325			return TCM_UNSUPPORTED_SCSI_OPCODE;
 326		}
 327		cmd->execute_cmd = sbc_execute_write_same_unmap;
 328		return 0;
 329	}
 330	if (!ops->execute_write_same)
 331		return TCM_UNSUPPORTED_SCSI_OPCODE;
 332
 333	ret = sbc_check_prot(dev, cmd, flags >> 5, sectors, true);
 334	if (ret)
 335		return ret;
 336
 337	cmd->execute_cmd = ops->execute_write_same;
 338	return 0;
 339}
 340
 341static sense_reason_t
 342sbc_execute_rw(struct se_cmd *cmd)
 343{
 344	struct exec_cmd_ops *ops = cmd->protocol_data;
 345
 346	return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 347			       cmd->data_direction);
 348}
 349
 350static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
 351					     int *post_ret)
 352{
 353	struct se_device *dev = cmd->se_dev;
 
 
 354	sense_reason_t ret = TCM_NO_SENSE;
 355
 356	spin_lock_irq(&cmd->t_state_lock);
 357	if (success) {
 358		*post_ret = 1;
 359
 360		if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 361			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 
 
 
 
 
 
 
 
 
 362	}
 363	spin_unlock_irq(&cmd->t_state_lock);
 
 
 
 
 
 
 
 364
 365	/*
 366	 * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 367	 * before the original READ I/O submission.
 368	 */
 369	up(&dev->caw_sem);
 370
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 371	return ret;
 372}
 373
 374/*
 375 * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare, fill
 376 * @miscmp_off and return TCM_MISCOMPARE_VERIFY.
 377 */
 378static sense_reason_t
 379compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents,
 380			 struct scatterlist *cmp_sgl, unsigned int cmp_nents,
 381			 unsigned int cmp_len, unsigned int *miscmp_off)
 382{
 383	unsigned char *buf = NULL;
 384	struct scatterlist *sg;
 385	sense_reason_t ret;
 386	unsigned int offset;
 387	size_t rc;
 388	int sg_cnt;
 389
 390	buf = kzalloc(cmp_len, GFP_KERNEL);
 391	if (!buf) {
 392		ret = TCM_OUT_OF_RESOURCES;
 393		goto out;
 394	}
 395
 396	rc = sg_copy_to_buffer(cmp_sgl, cmp_nents, buf, cmp_len);
 397	if (!rc) {
 398		pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 399		ret = TCM_OUT_OF_RESOURCES;
 400		goto out;
 401	}
 402	/*
 403	 * Compare SCSI READ payload against verify payload
 
 
 404	 */
 405	offset = 0;
 406	ret = TCM_NO_SENSE;
 407	for_each_sg(read_sgl, sg, read_nents, sg_cnt) {
 408		unsigned int len = min(sg->length, cmp_len);
 409		unsigned char *addr = kmap_atomic(sg_page(sg));
 410
 411		if (memcmp(addr, buf + offset, len)) {
 412			unsigned int i;
 413
 414			for (i = 0; i < len && addr[i] == buf[offset + i]; i++)
 415				;
 416			*miscmp_off = offset + i;
 417			pr_warn("Detected MISCOMPARE at offset %u\n",
 418				*miscmp_off);
 419			ret = TCM_MISCOMPARE_VERIFY;
 420		}
 421		kunmap_atomic(addr);
 422		if (ret != TCM_NO_SENSE)
 423			goto out;
 424
 425		offset += len;
 426		cmp_len -= len;
 427		if (!cmp_len)
 428			break;
 429	}
 430	pr_debug("COMPARE AND WRITE read data matches compare data\n");
 431out:
 432	kfree(buf);
 433	return ret;
 434}
 435
 436static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
 437						 int *post_ret)
 438{
 439	struct se_device *dev = cmd->se_dev;
 440	struct sg_table write_tbl = { };
 441	struct scatterlist *write_sg;
 442	struct sg_mapping_iter m;
 443	unsigned int len;
 
 444	unsigned int block_size = dev->dev_attrib.block_size;
 445	unsigned int compare_len = (cmd->t_task_nolb * block_size);
 446	unsigned int miscmp_off = 0;
 447	sense_reason_t ret = TCM_NO_SENSE;
 448	int i;
 449
 450	if (!success) {
 451		/*
 452		 * Handle early failure in transport_generic_request_failure(),
 453		 * which will not have taken ->caw_sem yet..
 454		 */
 455		if (!cmd->t_data_sg || !cmd->t_bidi_data_sg)
 456			return TCM_NO_SENSE;
 457
 458		/*
 459		 * The command has been stopped or aborted so
 460		 * we don't have to perform the write operation.
 461		 */
 462		WARN_ON(!(cmd->transport_state &
 463			(CMD_T_ABORTED | CMD_T_STOP)));
 464		goto out;
 465	}
 466	/*
 467	 * Handle special case for zero-length COMPARE_AND_WRITE
 
 468	 */
 469	if (!cmd->data_length)
 470		goto out;
 471	/*
 472	 * Immediately exit + release dev->caw_sem if command has already
 473	 * been failed with a non-zero SCSI status.
 474	 */
 475	if (cmd->scsi_status) {
 476		pr_debug("compare_and_write_callback: non zero scsi_status:"
 477			" 0x%02x\n", cmd->scsi_status);
 478		*post_ret = 1;
 479		if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
 480			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 481		goto out;
 482	}
 483
 484	ret = compare_and_write_do_cmp(cmd->t_bidi_data_sg,
 485				       cmd->t_bidi_data_nents,
 486				       cmd->t_data_sg,
 487				       cmd->t_data_nents,
 488				       compare_len,
 489				       &miscmp_off);
 490	if (ret == TCM_MISCOMPARE_VERIFY) {
 491		/*
 492		 * SBC-4 r15: 5.3 COMPARE AND WRITE command
 493		 * In the sense data (see 4.18 and SPC-5) the offset from the
 494		 * start of the Data-Out Buffer to the first byte of data that
 495		 * was not equal shall be reported in the INFORMATION field.
 496		 */
 497		cmd->sense_info = miscmp_off;
 498		goto out;
 499	} else if (ret)
 500		goto out;
 
 501
 502	if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) {
 
 
 503		pr_err("Unable to allocate compare_and_write sg\n");
 504		ret = TCM_OUT_OF_RESOURCES;
 505		goto out;
 506	}
 507	write_sg = write_tbl.sgl;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 508
 509	i = 0;
 510	len = compare_len;
 511	sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 512	/*
 513	 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 514	 */
 515	while (len) {
 516		sg_miter_next(&m);
 517
 518		if (block_size < PAGE_SIZE) {
 519			sg_set_page(&write_sg[i], m.page, block_size,
 520				    m.piter.sg->offset + block_size);
 521		} else {
 522			sg_miter_next(&m);
 523			sg_set_page(&write_sg[i], m.page, block_size,
 524				    m.piter.sg->offset);
 525		}
 526		len -= block_size;
 527		i++;
 528	}
 529	sg_miter_stop(&m);
 530	/*
 531	 * Save the original SGL + nents values before updating to new
 532	 * assignments, to be released in transport_free_pages() ->
 533	 * transport_reset_sgl_orig()
 534	 */
 535	cmd->t_data_sg_orig = cmd->t_data_sg;
 536	cmd->t_data_sg = write_sg;
 537	cmd->t_data_nents_orig = cmd->t_data_nents;
 538	cmd->t_data_nents = 1;
 539
 540	cmd->sam_task_attr = TCM_HEAD_TAG;
 541	cmd->transport_complete_callback = compare_and_write_post;
 542	/*
 543	 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 544	 * for submitting the adjusted SGL to write instance user-data.
 545	 */
 546	cmd->execute_cmd = sbc_execute_rw;
 547
 548	spin_lock_irq(&cmd->t_state_lock);
 549	cmd->t_state = TRANSPORT_PROCESSING;
 550	cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
 551	spin_unlock_irq(&cmd->t_state_lock);
 552
 553	__target_execute_cmd(cmd, false);
 554
 
 555	return ret;
 556
 
 
 
 
 557out:
 558	/*
 559	 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 560	 * sbc_compare_and_write() before the original READ I/O submission.
 561	 */
 562	up(&dev->caw_sem);
 563	sg_free_table(&write_tbl);
 
 564	return ret;
 565}
 566
 567static sense_reason_t
 568sbc_compare_and_write(struct se_cmd *cmd)
 569{
 570	struct exec_cmd_ops *ops = cmd->protocol_data;
 571	struct se_device *dev = cmd->se_dev;
 572	sense_reason_t ret;
 573	int rc;
 574	/*
 575	 * Submit the READ first for COMPARE_AND_WRITE to perform the
 576	 * comparision using SGLs at cmd->t_bidi_data_sg..
 577	 */
 578	rc = down_interruptible(&dev->caw_sem);
 579	if (rc != 0) {
 580		cmd->transport_complete_callback = NULL;
 581		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 582	}
 583	/*
 584	 * Reset cmd->data_length to individual block_size in order to not
 585	 * confuse backend drivers that depend on this value matching the
 586	 * size of the I/O being submitted.
 587	 */
 588	cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 589
 590	ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 591			      DMA_FROM_DEVICE);
 592	if (ret) {
 593		cmd->transport_complete_callback = NULL;
 594		up(&dev->caw_sem);
 595		return ret;
 596	}
 597	/*
 598	 * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 599	 * upon MISCOMPARE, or in compare_and_write_done() upon completion
 600	 * of WRITE instance user-data.
 601	 */
 602	return TCM_NO_SENSE;
 603}
 604
 605static int
 606sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
 607		       bool is_write, struct se_cmd *cmd)
 608{
 609	if (is_write) {
 610		cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
 611			       protect ? TARGET_PROT_DOUT_PASS :
 612			       TARGET_PROT_DOUT_INSERT;
 613		switch (protect) {
 614		case 0x0:
 615		case 0x3:
 616			cmd->prot_checks = 0;
 617			break;
 618		case 0x1:
 619		case 0x5:
 620			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 621			if (prot_type == TARGET_DIF_TYPE1_PROT)
 622				cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 623			break;
 624		case 0x2:
 625			if (prot_type == TARGET_DIF_TYPE1_PROT)
 626				cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 627			break;
 628		case 0x4:
 629			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 630			break;
 631		default:
 632			pr_err("Unsupported protect field %d\n", protect);
 633			return -EINVAL;
 634		}
 635	} else {
 636		cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
 637			       protect ? TARGET_PROT_DIN_PASS :
 638			       TARGET_PROT_DIN_STRIP;
 639		switch (protect) {
 640		case 0x0:
 641		case 0x1:
 642		case 0x5:
 643			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 644			if (prot_type == TARGET_DIF_TYPE1_PROT)
 645				cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 646			break;
 647		case 0x2:
 648			if (prot_type == TARGET_DIF_TYPE1_PROT)
 649				cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 650			break;
 651		case 0x3:
 652			cmd->prot_checks = 0;
 653			break;
 654		case 0x4:
 655			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 656			break;
 657		default:
 658			pr_err("Unsupported protect field %d\n", protect);
 659			return -EINVAL;
 660		}
 661	}
 662
 663	return 0;
 664}
 665
 666static sense_reason_t
 667sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char protect,
 668	       u32 sectors, bool is_write)
 669{
 670	int sp_ops = cmd->se_sess->sup_prot_ops;
 671	int pi_prot_type = dev->dev_attrib.pi_prot_type;
 672	bool fabric_prot = false;
 673
 674	if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
 675		if (unlikely(protect &&
 676		    !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
 677			pr_err("CDB contains protect bit, but device + fabric does"
 678			       " not advertise PROTECT=1 feature bit\n");
 679			return TCM_INVALID_CDB_FIELD;
 680		}
 681		if (cmd->prot_pto)
 682			return TCM_NO_SENSE;
 683	}
 684
 685	switch (dev->dev_attrib.pi_prot_type) {
 686	case TARGET_DIF_TYPE3_PROT:
 687		cmd->reftag_seed = 0xffffffff;
 688		break;
 689	case TARGET_DIF_TYPE2_PROT:
 690		if (protect)
 691			return TCM_INVALID_CDB_FIELD;
 692
 693		cmd->reftag_seed = cmd->t_task_lba;
 694		break;
 695	case TARGET_DIF_TYPE1_PROT:
 696		cmd->reftag_seed = cmd->t_task_lba;
 697		break;
 698	case TARGET_DIF_TYPE0_PROT:
 699		/*
 700		 * See if the fabric supports T10-PI, and the session has been
 701		 * configured to allow export PROTECT=1 feature bit with backend
 702		 * devices that don't support T10-PI.
 703		 */
 704		fabric_prot = is_write ?
 705			      !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
 706			      !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
 707
 708		if (fabric_prot && cmd->se_sess->sess_prot_type) {
 709			pi_prot_type = cmd->se_sess->sess_prot_type;
 710			break;
 711		}
 712		if (!protect)
 713			return TCM_NO_SENSE;
 714		fallthrough;
 715	default:
 716		pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
 717		       "PROTECT: 0x%02x\n", cmd->t_task_cdb[0], protect);
 718		return TCM_INVALID_CDB_FIELD;
 719	}
 720
 721	if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
 722		return TCM_INVALID_CDB_FIELD;
 
 723
 724	cmd->prot_type = pi_prot_type;
 725	cmd->prot_length = dev->prot_length * sectors;
 726
 727	/**
 728	 * In case protection information exists over the wire
 729	 * we modify command data length to describe pure data.
 730	 * The actual transfer length is data length + protection
 731	 * length
 732	 **/
 733	if (protect)
 734		cmd->data_length = sectors * dev->dev_attrib.block_size;
 735
 736	pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
 737		 "prot_op=%d prot_checks=%d\n",
 738		 __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
 739		 cmd->prot_op, cmd->prot_checks);
 740
 741	return TCM_NO_SENSE;
 742}
 743
 744static int
 745sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
 746{
 747	if (cdb[1] & 0x10) {
 748		/* see explanation in spc_emulate_modesense */
 749		if (!target_check_fua(dev)) {
 750			pr_err("Got CDB: 0x%02x with DPO bit set, but device"
 751			       " does not advertise support for DPO\n", cdb[0]);
 752			return -EINVAL;
 753		}
 754	}
 755	if (cdb[1] & 0x8) {
 756		if (!target_check_fua(dev)) {
 757			pr_err("Got CDB: 0x%02x with FUA bit set, but device"
 758			       " does not advertise support for FUA write\n",
 759			       cdb[0]);
 760			return -EINVAL;
 761		}
 762		cmd->se_cmd_flags |= SCF_FUA;
 763	}
 764	return 0;
 765}
 766
 767sense_reason_t
 768sbc_parse_cdb(struct se_cmd *cmd, struct exec_cmd_ops *ops)
 769{
 770	struct se_device *dev = cmd->se_dev;
 771	unsigned char *cdb = cmd->t_task_cdb;
 772	unsigned int size;
 773	u32 sectors = 0;
 774	sense_reason_t ret;
 775
 776	cmd->protocol_data = ops;
 777
 778	switch (cdb[0]) {
 779	case READ_6:
 780		sectors = transport_get_sectors_6(cdb);
 781		cmd->t_task_lba = transport_lba_21(cdb);
 782		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 783		cmd->execute_cmd = sbc_execute_rw;
 784		break;
 785	case READ_10:
 786		sectors = transport_get_sectors_10(cdb);
 787		cmd->t_task_lba = transport_lba_32(cdb);
 788
 789		if (sbc_check_dpofua(dev, cmd, cdb))
 790			return TCM_INVALID_CDB_FIELD;
 791
 792		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
 793		if (ret)
 794			return ret;
 795
 796		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 797		cmd->execute_cmd = sbc_execute_rw;
 798		break;
 799	case READ_12:
 800		sectors = transport_get_sectors_12(cdb);
 801		cmd->t_task_lba = transport_lba_32(cdb);
 802
 803		if (sbc_check_dpofua(dev, cmd, cdb))
 804			return TCM_INVALID_CDB_FIELD;
 805
 806		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
 807		if (ret)
 808			return ret;
 809
 810		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 811		cmd->execute_cmd = sbc_execute_rw;
 812		break;
 813	case READ_16:
 814		sectors = transport_get_sectors_16(cdb);
 815		cmd->t_task_lba = transport_lba_64(cdb);
 816
 817		if (sbc_check_dpofua(dev, cmd, cdb))
 818			return TCM_INVALID_CDB_FIELD;
 819
 820		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
 821		if (ret)
 822			return ret;
 823
 824		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 825		cmd->execute_cmd = sbc_execute_rw;
 826		break;
 827	case WRITE_6:
 828		sectors = transport_get_sectors_6(cdb);
 829		cmd->t_task_lba = transport_lba_21(cdb);
 830		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 831		cmd->execute_cmd = sbc_execute_rw;
 832		break;
 833	case WRITE_10:
 834	case WRITE_VERIFY:
 835		sectors = transport_get_sectors_10(cdb);
 836		cmd->t_task_lba = transport_lba_32(cdb);
 837
 838		if (sbc_check_dpofua(dev, cmd, cdb))
 839			return TCM_INVALID_CDB_FIELD;
 840
 841		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
 842		if (ret)
 843			return ret;
 844
 
 
 845		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 846		cmd->execute_cmd = sbc_execute_rw;
 847		break;
 848	case WRITE_12:
 849		sectors = transport_get_sectors_12(cdb);
 850		cmd->t_task_lba = transport_lba_32(cdb);
 851
 852		if (sbc_check_dpofua(dev, cmd, cdb))
 853			return TCM_INVALID_CDB_FIELD;
 854
 855		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
 856		if (ret)
 857			return ret;
 858
 
 
 859		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 860		cmd->execute_cmd = sbc_execute_rw;
 861		break;
 862	case WRITE_16:
 863	case WRITE_VERIFY_16:
 864		sectors = transport_get_sectors_16(cdb);
 865		cmd->t_task_lba = transport_lba_64(cdb);
 866
 867		if (sbc_check_dpofua(dev, cmd, cdb))
 868			return TCM_INVALID_CDB_FIELD;
 869
 870		ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
 871		if (ret)
 872			return ret;
 
 
 
 
 
 
 
 
 873
 
 874		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 
 
 
 
 
 875		cmd->execute_cmd = sbc_execute_rw;
 
 
 
 876		break;
 877	case VARIABLE_LENGTH_CMD:
 878	{
 879		u16 service_action = get_unaligned_be16(&cdb[8]);
 880		switch (service_action) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 881		case WRITE_SAME_32:
 882			sectors = transport_get_sectors_32(cdb);
 883			if (!sectors) {
 884				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 885				       " supported\n");
 886				return TCM_INVALID_CDB_FIELD;
 887			}
 888
 889			size = sbc_get_size(cmd, 1);
 890			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 891
 892			ret = sbc_setup_write_same(cmd, cdb[10], ops);
 893			if (ret)
 894				return ret;
 895			break;
 896		default:
 897			pr_err("VARIABLE_LENGTH_CMD service action"
 898				" 0x%04x not supported\n", service_action);
 899			return TCM_UNSUPPORTED_SCSI_OPCODE;
 900		}
 901		break;
 902	}
 903	case COMPARE_AND_WRITE:
 904		if (!dev->dev_attrib.emulate_caw) {
 905			pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
 906					   dev->se_hba->backend->ops->name,
 907					   config_item_name(&dev->dev_group.cg_item),
 908					   dev->t10_wwn.unit_serial);
 909			return TCM_UNSUPPORTED_SCSI_OPCODE;
 910		}
 911		sectors = cdb[13];
 912		/*
 913		 * Currently enforce COMPARE_AND_WRITE for a single sector
 914		 */
 915		if (sectors > 1) {
 916			pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 917			       " than 1\n", sectors);
 918			return TCM_INVALID_CDB_FIELD;
 919		}
 920		if (sbc_check_dpofua(dev, cmd, cdb))
 921			return TCM_INVALID_CDB_FIELD;
 922
 923		/*
 924		 * Double size because we have two buffers, note that
 925		 * zero is not an error..
 926		 */
 927		size = 2 * sbc_get_size(cmd, sectors);
 928		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 929		cmd->t_task_nolb = sectors;
 930		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
 
 931		cmd->execute_cmd = sbc_compare_and_write;
 932		cmd->transport_complete_callback = compare_and_write_callback;
 933		break;
 934	case READ_CAPACITY:
 935		size = READ_CAP_LEN;
 936		cmd->execute_cmd = sbc_emulate_readcapacity;
 937		break;
 938	case SERVICE_ACTION_IN_16:
 939		switch (cmd->t_task_cdb[1] & 0x1f) {
 940		case SAI_READ_CAPACITY_16:
 941			cmd->execute_cmd = sbc_emulate_readcapacity_16;
 942			break;
 943		case SAI_REPORT_REFERRALS:
 944			cmd->execute_cmd = target_emulate_report_referrals;
 945			break;
 946		default:
 947			pr_err("Unsupported SA: 0x%02x\n",
 948				cmd->t_task_cdb[1] & 0x1f);
 949			return TCM_INVALID_CDB_FIELD;
 950		}
 951		size = get_unaligned_be32(&cdb[10]);
 
 952		break;
 953	case SYNCHRONIZE_CACHE:
 954	case SYNCHRONIZE_CACHE_16:
 
 
 
 
 
 
 
 
 
 955		if (cdb[0] == SYNCHRONIZE_CACHE) {
 956			sectors = transport_get_sectors_10(cdb);
 957			cmd->t_task_lba = transport_lba_32(cdb);
 958		} else {
 959			sectors = transport_get_sectors_16(cdb);
 960			cmd->t_task_lba = transport_lba_64(cdb);
 961		}
 962		if (ops->execute_sync_cache) {
 963			cmd->execute_cmd = ops->execute_sync_cache;
 964			goto check_lba;
 
 
 
 
 
 
 
 965		}
 966		size = 0;
 967		cmd->execute_cmd = sbc_emulate_noop;
 968		break;
 969	case UNMAP:
 970		if (!ops->execute_unmap)
 971			return TCM_UNSUPPORTED_SCSI_OPCODE;
 972
 973		if (!dev->dev_attrib.emulate_tpu) {
 974			pr_err("Got UNMAP, but backend device has"
 975			       " emulate_tpu disabled\n");
 976			return TCM_UNSUPPORTED_SCSI_OPCODE;
 977		}
 978		size = get_unaligned_be16(&cdb[7]);
 979		cmd->execute_cmd = sbc_execute_unmap;
 980		break;
 981	case WRITE_SAME_16:
 982		sectors = transport_get_sectors_16(cdb);
 983		if (!sectors) {
 984			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 985			return TCM_INVALID_CDB_FIELD;
 986		}
 987
 988		size = sbc_get_size(cmd, 1);
 989		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 990
 991		ret = sbc_setup_write_same(cmd, cdb[1], ops);
 992		if (ret)
 993			return ret;
 994		break;
 995	case WRITE_SAME:
 996		sectors = transport_get_sectors_10(cdb);
 997		if (!sectors) {
 998			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 999			return TCM_INVALID_CDB_FIELD;
1000		}
1001
1002		size = sbc_get_size(cmd, 1);
1003		cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1004
1005		/*
1006		 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1007		 * of byte 1 bit 3 UNMAP instead of original reserved field
1008		 */
1009		ret = sbc_setup_write_same(cmd, cdb[1], ops);
1010		if (ret)
1011			return ret;
1012		break;
1013	case VERIFY:
1014	case VERIFY_16:
1015		size = 0;
1016		if (cdb[0] == VERIFY) {
1017			sectors = transport_get_sectors_10(cdb);
1018			cmd->t_task_lba = transport_lba_32(cdb);
1019		} else {
1020			sectors = transport_get_sectors_16(cdb);
1021			cmd->t_task_lba = transport_lba_64(cdb);
1022		}
1023		cmd->execute_cmd = sbc_emulate_noop;
1024		goto check_lba;
1025	case REZERO_UNIT:
1026	case SEEK_6:
1027	case SEEK_10:
1028		/*
1029		 * There are still clients out there which use these old SCSI-2
1030		 * commands. This mainly happens when running VMs with legacy
1031		 * guest systems, connected via SCSI command pass-through to
1032		 * iSCSI targets. Make them happy and return status GOOD.
1033		 */
1034		size = 0;
1035		cmd->execute_cmd = sbc_emulate_noop;
1036		break;
1037	case START_STOP:
1038		size = 0;
1039		cmd->execute_cmd = sbc_emulate_startstop;
1040		break;
1041	default:
1042		ret = spc_parse_cdb(cmd, &size);
1043		if (ret)
1044			return ret;
1045	}
1046
1047	/* reject any command that we don't have a handler for */
1048	if (!cmd->execute_cmd)
1049		return TCM_UNSUPPORTED_SCSI_OPCODE;
1050
1051	if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1052		unsigned long long end_lba;
1053check_lba:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1054		end_lba = dev->transport->get_blocks(dev) + 1;
1055		if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1056		    ((cmd->t_task_lba + sectors) > end_lba)) {
1057			pr_err("cmd exceeds last lba %llu "
1058				"(lba %llu, sectors %u)\n",
1059				end_lba, cmd->t_task_lba, sectors);
1060			return TCM_ADDRESS_OUT_OF_RANGE;
1061		}
1062
1063		if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1064			size = sbc_get_size(cmd, sectors);
1065	}
1066
1067	return target_cmd_size_check(cmd, size);
1068}
1069EXPORT_SYMBOL(sbc_parse_cdb);
1070
1071u32 sbc_get_device_type(struct se_device *dev)
1072{
1073	return TYPE_DISK;
1074}
1075EXPORT_SYMBOL(sbc_get_device_type);
1076
1077static sense_reason_t
1078sbc_execute_unmap(struct se_cmd *cmd)
 
 
 
1079{
1080	struct exec_cmd_ops *ops = cmd->protocol_data;
1081	struct se_device *dev = cmd->se_dev;
1082	unsigned char *buf, *ptr = NULL;
1083	sector_t lba;
1084	int size;
1085	u32 range;
1086	sense_reason_t ret = 0;
1087	int dl, bd_dl;
1088
1089	/* We never set ANC_SUP */
1090	if (cmd->t_task_cdb[1])
1091		return TCM_INVALID_CDB_FIELD;
1092
1093	if (cmd->data_length == 0) {
1094		target_complete_cmd(cmd, SAM_STAT_GOOD);
1095		return 0;
1096	}
1097
1098	if (cmd->data_length < 8) {
1099		pr_warn("UNMAP parameter list length %u too small\n",
1100			cmd->data_length);
1101		return TCM_PARAMETER_LIST_LENGTH_ERROR;
1102	}
1103
1104	buf = transport_kmap_data_sg(cmd);
1105	if (!buf)
1106		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1107
1108	dl = get_unaligned_be16(&buf[0]);
1109	bd_dl = get_unaligned_be16(&buf[2]);
1110
1111	size = cmd->data_length - 8;
1112	if (bd_dl > size)
1113		pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1114			cmd->data_length, bd_dl);
1115	else
1116		size = bd_dl;
1117
1118	if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1119		ret = TCM_INVALID_PARAMETER_LIST;
1120		goto err;
1121	}
1122
1123	/* First UNMAP block descriptor starts at 8 byte offset */
1124	ptr = &buf[8];
1125	pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1126		" ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1127
1128	while (size >= 16) {
1129		lba = get_unaligned_be64(&ptr[0]);
1130		range = get_unaligned_be32(&ptr[8]);
1131		pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1132				 (unsigned long long)lba, range);
1133
1134		if (range > dev->dev_attrib.max_unmap_lba_count) {
1135			ret = TCM_INVALID_PARAMETER_LIST;
1136			goto err;
1137		}
1138
1139		if (lba + range > dev->transport->get_blocks(dev) + 1) {
1140			ret = TCM_ADDRESS_OUT_OF_RANGE;
1141			goto err;
1142		}
1143
1144		if (range) {
1145			ret = ops->execute_unmap(cmd, lba, range);
1146			if (ret)
1147				goto err;
1148		}
1149
1150		ptr += 16;
1151		size -= 16;
1152	}
1153
1154err:
1155	transport_kunmap_data_sg(cmd);
1156	if (!ret)
1157		target_complete_cmd(cmd, SAM_STAT_GOOD);
1158	return ret;
1159}
 
1160
1161void
1162sbc_dif_generate(struct se_cmd *cmd)
1163{
1164	struct se_device *dev = cmd->se_dev;
1165	struct t10_pi_tuple *sdt;
1166	struct scatterlist *dsg = cmd->t_data_sg, *psg;
1167	sector_t sector = cmd->t_task_lba;
1168	void *daddr, *paddr;
1169	int i, j, offset = 0;
1170	unsigned int block_size = dev->dev_attrib.block_size;
1171
1172	for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1173		paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1174		daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
 
1175
1176		for (j = 0; j < psg->length;
1177				j += sizeof(*sdt)) {
1178			__u16 crc;
1179			unsigned int avail;
1180
1181			if (offset >= dsg->length) {
1182				offset -= dsg->length;
1183				kunmap_atomic(daddr - dsg->offset);
1184				dsg = sg_next(dsg);
1185				if (!dsg) {
1186					kunmap_atomic(paddr - psg->offset);
1187					return;
1188				}
1189				daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1190			}
1191
1192			sdt = paddr + j;
1193			avail = min(block_size, dsg->length - offset);
1194			crc = crc_t10dif(daddr + offset, avail);
1195			if (avail < block_size) {
1196				kunmap_atomic(daddr - dsg->offset);
1197				dsg = sg_next(dsg);
1198				if (!dsg) {
1199					kunmap_atomic(paddr - psg->offset);
1200					return;
1201				}
1202				daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1203				offset = block_size - avail;
1204				crc = crc_t10dif_update(crc, daddr, offset);
1205			} else {
1206				offset += block_size;
1207			}
1208
1209			sdt->guard_tag = cpu_to_be16(crc);
1210			if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
 
 
1211				sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1212			sdt->app_tag = 0;
1213
1214			pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1215				 " app_tag: 0x%04x ref_tag: %u\n",
1216				 (cmd->data_direction == DMA_TO_DEVICE) ?
1217				 "WRITE" : "READ", (unsigned long long)sector,
1218				 sdt->guard_tag, sdt->app_tag,
1219				 be32_to_cpu(sdt->ref_tag));
1220
1221			sector++;
 
1222		}
1223
1224		kunmap_atomic(daddr - dsg->offset);
1225		kunmap_atomic(paddr - psg->offset);
1226	}
1227}
1228
1229static sense_reason_t
1230sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1231		  __u16 crc, sector_t sector, unsigned int ei_lba)
1232{
 
1233	__be16 csum;
1234
1235	if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1236		goto check_ref;
1237
1238	csum = cpu_to_be16(crc);
1239
1240	if (sdt->guard_tag != csum) {
1241		pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1242			" csum 0x%04x\n", (unsigned long long)sector,
1243			be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1244		return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1245	}
1246
1247check_ref:
1248	if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1249		return 0;
1250
1251	if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1252	    be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1253		pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1254		       " sector MSB: 0x%08x\n", (unsigned long long)sector,
1255		       be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1256		return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1257	}
1258
1259	if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1260	    be32_to_cpu(sdt->ref_tag) != ei_lba) {
1261		pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1262		       " ei_lba: 0x%08x\n", (unsigned long long)sector,
1263			be32_to_cpu(sdt->ref_tag), ei_lba);
1264		return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1265	}
1266
1267	return 0;
1268}
1269
1270void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1271		       struct scatterlist *sg, int sg_off)
 
1272{
1273	struct se_device *dev = cmd->se_dev;
1274	struct scatterlist *psg;
1275	void *paddr, *addr;
1276	unsigned int i, len, left;
1277	unsigned int offset = sg_off;
1278
1279	if (!sg)
1280		return;
1281
1282	left = sectors * dev->prot_length;
1283
1284	for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1285		unsigned int psg_len, copied = 0;
1286
1287		paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1288		psg_len = min(left, psg->length);
1289		while (psg_len) {
1290			len = min(psg_len, sg->length - offset);
1291			addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1292
1293			if (read)
1294				memcpy(paddr + copied, addr, len);
1295			else
1296				memcpy(addr, paddr + copied, len);
1297
1298			left -= len;
1299			offset += len;
1300			copied += len;
1301			psg_len -= len;
1302
1303			kunmap_atomic(addr - sg->offset - offset);
1304
1305			if (offset >= sg->length) {
1306				sg = sg_next(sg);
1307				offset = 0;
1308			}
 
1309		}
1310		kunmap_atomic(paddr - psg->offset);
1311	}
1312}
1313EXPORT_SYMBOL(sbc_dif_copy_prot);
1314
1315sense_reason_t
1316sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1317	       unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1318{
1319	struct se_device *dev = cmd->se_dev;
1320	struct t10_pi_tuple *sdt;
1321	struct scatterlist *dsg = cmd->t_data_sg;
1322	sector_t sector = start;
1323	void *daddr, *paddr;
1324	int i;
1325	sense_reason_t rc;
1326	int dsg_off = 0;
1327	unsigned int block_size = dev->dev_attrib.block_size;
1328
1329	for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1330		paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1331		daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
 
 
 
1332
1333		for (i = psg_off; i < psg->length &&
1334				sector < start + sectors;
1335				i += sizeof(*sdt)) {
1336			__u16 crc;
1337			unsigned int avail;
1338
1339			if (dsg_off >= dsg->length) {
1340				dsg_off -= dsg->length;
1341				kunmap_atomic(daddr - dsg->offset);
1342				dsg = sg_next(dsg);
1343				if (!dsg) {
1344					kunmap_atomic(paddr - psg->offset);
1345					return 0;
1346				}
1347				daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1348			}
1349
1350			sdt = paddr + i;
1351
1352			pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1353				 " app_tag: 0x%04x ref_tag: %u\n",
1354				 (unsigned long long)sector, sdt->guard_tag,
1355				 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1356
1357			if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1358				dsg_off += block_size;
1359				goto next;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1360			}
1361
1362			avail = min(block_size, dsg->length - dsg_off);
1363			crc = crc_t10dif(daddr + dsg_off, avail);
1364			if (avail < block_size) {
1365				kunmap_atomic(daddr - dsg->offset);
1366				dsg = sg_next(dsg);
1367				if (!dsg) {
1368					kunmap_atomic(paddr - psg->offset);
1369					return 0;
1370				}
1371				daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1372				dsg_off = block_size - avail;
1373				crc = crc_t10dif_update(crc, daddr, dsg_off);
1374			} else {
1375				dsg_off += block_size;
1376			}
1377
1378			rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
 
1379			if (rc) {
1380				kunmap_atomic(daddr - dsg->offset);
1381				kunmap_atomic(paddr - psg->offset);
1382				cmd->sense_info = sector;
1383				return rc;
1384			}
1385next:
1386			sector++;
1387			ei_lba++;
 
1388		}
1389
1390		psg_off = 0;
1391		kunmap_atomic(daddr - dsg->offset);
1392		kunmap_atomic(paddr - psg->offset);
1393	}
1394
1395	return 0;
1396}
1397EXPORT_SYMBOL(sbc_dif_verify);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v3.15
 
   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
  39static sense_reason_t
 
 
 
 
  40sbc_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
  88static sense_reason_t
  89sbc_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(cmd, GOOD);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 141	return 0;
 142}
 143
 144sector_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}
 165EXPORT_SYMBOL(sbc_get_write_same_sectors);
 166
 167static sense_reason_t
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 168sbc_emulate_noop(struct se_cmd *cmd)
 169{
 170	target_complete_cmd(cmd, GOOD);
 171	return 0;
 172}
 173
 174static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 175{
 176	return cmd->se_dev->dev_attrib.block_size * sectors;
 177}
 178
 179static int sbc_check_valid_sectors(struct se_cmd *cmd)
 180{
 181	struct se_device *dev = cmd->se_dev;
 182	unsigned long long end_lba;
 183	u32 sectors;
 184
 185	sectors = cmd->data_length / dev->dev_attrib.block_size;
 186	end_lba = dev->transport->get_blocks(dev) + 1;
 187
 188	if (cmd->t_task_lba + sectors > end_lba) {
 189		pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n",
 190			cmd->t_task_lba, sectors, end_lba);
 191		return -EINVAL;
 192	}
 193
 194	return 0;
 195}
 196
 197static inline u32 transport_get_sectors_6(unsigned char *cdb)
 198{
 199	/*
 200	 * Use 8-bit sector value.  SBC-3 says:
 201	 *
 202	 *   A TRANSFER LENGTH field set to zero specifies that 256
 203	 *   logical blocks shall be written.  Any other value
 204	 *   specifies the number of logical blocks that shall be
 205	 *   written.
 206	 */
 207	return cdb[4] ? : 256;
 208}
 209
 210static inline u32 transport_get_sectors_10(unsigned char *cdb)
 211{
 212	return (u32)(cdb[7] << 8) + cdb[8];
 213}
 214
 215static inline u32 transport_get_sectors_12(unsigned char *cdb)
 216{
 217	return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
 218}
 219
 220static inline u32 transport_get_sectors_16(unsigned char *cdb)
 221{
 222	return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
 223		    (cdb[12] << 8) + cdb[13];
 224}
 225
 226/*
 227 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
 228 */
 229static inline u32 transport_get_sectors_32(unsigned char *cdb)
 230{
 231	return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
 232		    (cdb[30] << 8) + cdb[31];
 233
 234}
 235
 236static inline u32 transport_lba_21(unsigned char *cdb)
 237{
 238	return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
 239}
 240
 241static inline u32 transport_lba_32(unsigned char *cdb)
 242{
 243	return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 244}
 245
 246static inline unsigned long long transport_lba_64(unsigned char *cdb)
 247{
 248	unsigned int __v1, __v2;
 249
 250	__v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
 251	__v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
 252
 253	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 254}
 255
 256/*
 257 * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
 258 */
 259static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
 260{
 261	unsigned int __v1, __v2;
 262
 263	__v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
 264	__v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
 265
 266	return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
 267}
 268
 269static sense_reason_t
 270sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
 
 271{
 
 
 272	unsigned int sectors = sbc_get_write_same_sectors(cmd);
 
 273
 274	if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
 275		pr_err("WRITE_SAME PBDATA and LBDATA"
 276			" bits not supported for Block Discard"
 277			" Emulation\n");
 278		return TCM_UNSUPPORTED_SCSI_OPCODE;
 279	}
 280	if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
 281		pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
 282			sectors, cmd->se_dev->dev_attrib.max_write_same_len);
 283		return TCM_INVALID_CDB_FIELD;
 284	}
 
 
 
 
 
 
 
 
 
 
 285	/* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
 286	if (flags[0] & 0x10) {
 287		pr_warn("WRITE SAME with ANCHOR not supported\n");
 288		return TCM_INVALID_CDB_FIELD;
 289	}
 
 
 
 
 
 
 290	/*
 291	 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
 292	 * translated into block discard requests within backend code.
 293	 */
 294	if (flags[0] & 0x08) {
 295		if (!ops->execute_write_same_unmap)
 296			return TCM_UNSUPPORTED_SCSI_OPCODE;
 297
 298		cmd->execute_cmd = ops->execute_write_same_unmap;
 
 
 
 
 
 299		return 0;
 300	}
 301	if (!ops->execute_write_same)
 302		return TCM_UNSUPPORTED_SCSI_OPCODE;
 303
 
 
 
 
 304	cmd->execute_cmd = ops->execute_write_same;
 305	return 0;
 306}
 307
 308static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd)
 
 
 
 
 
 
 
 
 
 
 309{
 310	unsigned char *buf, *addr;
 311	struct scatterlist *sg;
 312	unsigned int offset;
 313	sense_reason_t ret = TCM_NO_SENSE;
 314	int i, count;
 315	/*
 316	 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
 317	 *
 318	 * 1) read the specified logical block(s);
 319	 * 2) transfer logical blocks from the data-out buffer;
 320	 * 3) XOR the logical blocks transferred from the data-out buffer with
 321	 *    the logical blocks read, storing the resulting XOR data in a buffer;
 322	 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
 323	 *    blocks transferred from the data-out buffer; and
 324	 * 5) transfer the resulting XOR data to the data-in buffer.
 325	 */
 326	buf = kmalloc(cmd->data_length, GFP_KERNEL);
 327	if (!buf) {
 328		pr_err("Unable to allocate xor_callback buf\n");
 329		return TCM_OUT_OF_RESOURCES;
 330	}
 331	/*
 332	 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
 333	 * into the locally allocated *buf
 334	 */
 335	sg_copy_to_buffer(cmd->t_data_sg,
 336			  cmd->t_data_nents,
 337			  buf,
 338			  cmd->data_length);
 339
 340	/*
 341	 * Now perform the XOR against the BIDI read memory located at
 342	 * cmd->t_mem_bidi_list
 343	 */
 
 344
 345	offset = 0;
 346	for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
 347		addr = kmap_atomic(sg_page(sg));
 348		if (!addr) {
 349			ret = TCM_OUT_OF_RESOURCES;
 350			goto out;
 351		}
 352
 353		for (i = 0; i < sg->length; i++)
 354			*(addr + sg->offset + i) ^= *(buf + offset + i);
 355
 356		offset += sg->length;
 357		kunmap_atomic(addr);
 358	}
 359
 360out:
 361	kfree(buf);
 362	return ret;
 363}
 364
 
 
 
 
 365static sense_reason_t
 366sbc_execute_rw(struct se_cmd *cmd)
 
 
 367{
 368	return cmd->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
 369			       cmd->data_direction);
 370}
 
 
 
 371
 372static sense_reason_t compare_and_write_post(struct se_cmd *cmd)
 373{
 374	struct se_device *dev = cmd->se_dev;
 
 
 375
 
 
 
 
 
 
 376	/*
 377	 * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
 378	 * within target_complete_ok_work() if the command was successfully
 379	 * sent to the backend driver.
 380	 */
 381	spin_lock_irq(&cmd->t_state_lock);
 382	if ((cmd->transport_state & CMD_T_SENT) && !cmd->scsi_status)
 383		cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
 384	spin_unlock_irq(&cmd->t_state_lock);
 
 
 
 
 385
 386	/*
 387	 * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
 388	 * before the original READ I/O submission.
 389	 */
 390	up(&dev->caw_sem);
 
 
 
 
 
 391
 392	return TCM_NO_SENSE;
 
 
 
 
 
 
 
 
 393}
 394
 395static sense_reason_t compare_and_write_callback(struct se_cmd *cmd)
 
 396{
 397	struct se_device *dev = cmd->se_dev;
 398	struct scatterlist *write_sg = NULL, *sg;
 399	unsigned char *buf = NULL, *addr;
 400	struct sg_mapping_iter m;
 401	unsigned int offset = 0, len;
 402	unsigned int nlbas = cmd->t_task_nolb;
 403	unsigned int block_size = dev->dev_attrib.block_size;
 404	unsigned int compare_len = (nlbas * block_size);
 
 405	sense_reason_t ret = TCM_NO_SENSE;
 406	int rc, i;
 
 
 
 
 
 
 
 
 407
 
 
 
 
 
 
 
 
 408	/*
 409	 * Handle early failure in transport_generic_request_failure(),
 410	 * which will not have taken ->caw_mutex yet..
 411	 */
 412	if (!cmd->t_data_sg || !cmd->t_bidi_data_sg)
 413		return TCM_NO_SENSE;
 414	/*
 415	 * Immediately exit + release dev->caw_sem if command has already
 416	 * been failed with a non-zero SCSI status.
 417	 */
 418	if (cmd->scsi_status) {
 419		pr_err("compare_and_write_callback: non zero scsi_status:"
 420			" 0x%02x\n", cmd->scsi_status);
 
 
 
 421		goto out;
 422	}
 423
 424	buf = kzalloc(cmd->data_length, GFP_KERNEL);
 425	if (!buf) {
 426		pr_err("Unable to allocate compare_and_write buf\n");
 427		ret = TCM_OUT_OF_RESOURCES;
 
 
 
 
 
 
 
 
 
 
 
 
 428		goto out;
 429	}
 430
 431	write_sg = kmalloc(sizeof(struct scatterlist) * cmd->t_data_nents,
 432			   GFP_KERNEL);
 433	if (!write_sg) {
 434		pr_err("Unable to allocate compare_and_write sg\n");
 435		ret = TCM_OUT_OF_RESOURCES;
 436		goto out;
 437	}
 438	sg_init_table(write_sg, cmd->t_data_nents);
 439	/*
 440	 * Setup verify and write data payloads from total NumberLBAs.
 441	 */
 442	rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
 443			       cmd->data_length);
 444	if (!rc) {
 445		pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
 446		ret = TCM_OUT_OF_RESOURCES;
 447		goto out;
 448	}
 449	/*
 450	 * Compare against SCSI READ payload against verify payload
 451	 */
 452	for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
 453		addr = (unsigned char *)kmap_atomic(sg_page(sg));
 454		if (!addr) {
 455			ret = TCM_OUT_OF_RESOURCES;
 456			goto out;
 457		}
 458
 459		len = min(sg->length, compare_len);
 460
 461		if (memcmp(addr, buf + offset, len)) {
 462			pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
 463				addr, buf + offset);
 464			kunmap_atomic(addr);
 465			goto miscompare;
 466		}
 467		kunmap_atomic(addr);
 468
 469		offset += len;
 470		compare_len -= len;
 471		if (!compare_len)
 472			break;
 473	}
 474
 475	i = 0;
 476	len = cmd->t_task_nolb * block_size;
 477	sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
 478	/*
 479	 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
 480	 */
 481	while (len) {
 482		sg_miter_next(&m);
 483
 484		if (block_size < PAGE_SIZE) {
 485			sg_set_page(&write_sg[i], m.page, block_size,
 486				    block_size);
 487		} else {
 488			sg_miter_next(&m);
 489			sg_set_page(&write_sg[i], m.page, block_size,
 490				    0);
 491		}
 492		len -= block_size;
 493		i++;
 494	}
 495	sg_miter_stop(&m);
 496	/*
 497	 * Save the original SGL + nents values before updating to new
 498	 * assignments, to be released in transport_free_pages() ->
 499	 * transport_reset_sgl_orig()
 500	 */
 501	cmd->t_data_sg_orig = cmd->t_data_sg;
 502	cmd->t_data_sg = write_sg;
 503	cmd->t_data_nents_orig = cmd->t_data_nents;
 504	cmd->t_data_nents = 1;
 505
 506	cmd->sam_task_attr = MSG_HEAD_TAG;
 507	cmd->transport_complete_callback = compare_and_write_post;
 508	/*
 509	 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
 510	 * for submitting the adjusted SGL to write instance user-data.
 511	 */
 512	cmd->execute_cmd = sbc_execute_rw;
 513
 514	spin_lock_irq(&cmd->t_state_lock);
 515	cmd->t_state = TRANSPORT_PROCESSING;
 516	cmd->transport_state |= CMD_T_ACTIVE|CMD_T_BUSY|CMD_T_SENT;
 517	spin_unlock_irq(&cmd->t_state_lock);
 518
 519	__target_execute_cmd(cmd);
 520
 521	kfree(buf);
 522	return ret;
 523
 524miscompare:
 525	pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
 526		dev->transport->name);
 527	ret = TCM_MISCOMPARE_VERIFY;
 528out:
 529	/*
 530	 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
 531	 * sbc_compare_and_write() before the original READ I/O submission.
 532	 */
 533	up(&dev->caw_sem);
 534	kfree(write_sg);
 535	kfree(buf);
 536	return ret;
 537}
 538
 539static sense_reason_t
 540sbc_compare_and_write(struct se_cmd *cmd)
 541{
 
 542	struct se_device *dev = cmd->se_dev;
 543	sense_reason_t ret;
 544	int rc;
 545	/*
 546	 * Submit the READ first for COMPARE_AND_WRITE to perform the
 547	 * comparision using SGLs at cmd->t_bidi_data_sg..
 548	 */
 549	rc = down_interruptible(&dev->caw_sem);
 550	if ((rc != 0) || signal_pending(current)) {
 551		cmd->transport_complete_callback = NULL;
 552		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 553	}
 554	/*
 555	 * Reset cmd->data_length to individual block_size in order to not
 556	 * confuse backend drivers that depend on this value matching the
 557	 * size of the I/O being submitted.
 558	 */
 559	cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
 560
 561	ret = cmd->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
 562			      DMA_FROM_DEVICE);
 563	if (ret) {
 564		cmd->transport_complete_callback = NULL;
 565		up(&dev->caw_sem);
 566		return ret;
 567	}
 568	/*
 569	 * Unlock of dev->caw_sem to occur in compare_and_write_callback()
 570	 * upon MISCOMPARE, or in compare_and_write_done() upon completion
 571	 * of WRITE instance user-data.
 572	 */
 573	return TCM_NO_SENSE;
 574}
 575
 576static int
 577sbc_set_prot_op_checks(u8 protect, enum target_prot_type prot_type,
 578		       bool is_write, struct se_cmd *cmd)
 579{
 580	if (is_write) {
 581		cmd->prot_op = protect ? TARGET_PROT_DOUT_PASS :
 582					 TARGET_PROT_DOUT_INSERT;
 
 583		switch (protect) {
 584		case 0x0:
 585		case 0x3:
 586			cmd->prot_checks = 0;
 587			break;
 588		case 0x1:
 589		case 0x5:
 590			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 591			if (prot_type == TARGET_DIF_TYPE1_PROT)
 592				cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 593			break;
 594		case 0x2:
 595			if (prot_type == TARGET_DIF_TYPE1_PROT)
 596				cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 597			break;
 598		case 0x4:
 599			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 600			break;
 601		default:
 602			pr_err("Unsupported protect field %d\n", protect);
 603			return -EINVAL;
 604		}
 605	} else {
 606		cmd->prot_op = protect ? TARGET_PROT_DIN_PASS :
 607					 TARGET_PROT_DIN_STRIP;
 
 608		switch (protect) {
 609		case 0x0:
 610		case 0x1:
 611		case 0x5:
 612			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 613			if (prot_type == TARGET_DIF_TYPE1_PROT)
 614				cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
 615			break;
 616		case 0x2:
 617			if (prot_type == TARGET_DIF_TYPE1_PROT)
 618				cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
 619			break;
 620		case 0x3:
 621			cmd->prot_checks = 0;
 622			break;
 623		case 0x4:
 624			cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
 625			break;
 626		default:
 627			pr_err("Unsupported protect field %d\n", protect);
 628			return -EINVAL;
 629		}
 630	}
 631
 632	return 0;
 633}
 634
 635static bool
 636sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
 637	       u32 sectors, bool is_write)
 638{
 639	u8 protect = cdb[1] >> 5;
 640
 641	if ((!cmd->t_prot_sg || !cmd->t_prot_nents) && cmd->prot_pto)
 642		return true;
 
 
 
 
 
 
 
 
 
 
 643
 644	switch (dev->dev_attrib.pi_prot_type) {
 645	case TARGET_DIF_TYPE3_PROT:
 646		cmd->reftag_seed = 0xffffffff;
 647		break;
 648	case TARGET_DIF_TYPE2_PROT:
 649		if (protect)
 650			return false;
 651
 652		cmd->reftag_seed = cmd->t_task_lba;
 653		break;
 654	case TARGET_DIF_TYPE1_PROT:
 655		cmd->reftag_seed = cmd->t_task_lba;
 656		break;
 657	case TARGET_DIF_TYPE0_PROT:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 658	default:
 659		return true;
 
 
 660	}
 661
 662	if (sbc_set_prot_op_checks(protect, dev->dev_attrib.pi_prot_type,
 663				   is_write, cmd))
 664		return false;
 665
 666	cmd->prot_type = dev->dev_attrib.pi_prot_type;
 667	cmd->prot_length = dev->prot_length * sectors;
 668	pr_debug("%s: prot_type=%d, prot_length=%d prot_op=%d prot_checks=%d\n",
 669		 __func__, cmd->prot_type, cmd->prot_length,
 
 
 
 
 
 
 
 
 
 
 
 670		 cmd->prot_op, cmd->prot_checks);
 671
 672	return true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 673}
 674
 675sense_reason_t
 676sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 677{
 678	struct se_device *dev = cmd->se_dev;
 679	unsigned char *cdb = cmd->t_task_cdb;
 680	unsigned int size;
 681	u32 sectors = 0;
 682	sense_reason_t ret;
 683
 
 
 684	switch (cdb[0]) {
 685	case READ_6:
 686		sectors = transport_get_sectors_6(cdb);
 687		cmd->t_task_lba = transport_lba_21(cdb);
 688		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 689		cmd->execute_rw = ops->execute_rw;
 690		cmd->execute_cmd = sbc_execute_rw;
 691		break;
 692	case READ_10:
 693		sectors = transport_get_sectors_10(cdb);
 694		cmd->t_task_lba = transport_lba_32(cdb);
 695
 696		if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 697			return TCM_UNSUPPORTED_SCSI_OPCODE;
 
 
 
 
 698
 699		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 700		cmd->execute_rw = ops->execute_rw;
 701		cmd->execute_cmd = sbc_execute_rw;
 702		break;
 703	case READ_12:
 704		sectors = transport_get_sectors_12(cdb);
 705		cmd->t_task_lba = transport_lba_32(cdb);
 706
 707		if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 708			return TCM_UNSUPPORTED_SCSI_OPCODE;
 
 
 
 
 709
 710		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 711		cmd->execute_rw = ops->execute_rw;
 712		cmd->execute_cmd = sbc_execute_rw;
 713		break;
 714	case READ_16:
 715		sectors = transport_get_sectors_16(cdb);
 716		cmd->t_task_lba = transport_lba_64(cdb);
 717
 718		if (!sbc_check_prot(dev, cmd, cdb, sectors, false))
 719			return TCM_UNSUPPORTED_SCSI_OPCODE;
 
 
 
 
 720
 721		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 722		cmd->execute_rw = ops->execute_rw;
 723		cmd->execute_cmd = sbc_execute_rw;
 724		break;
 725	case WRITE_6:
 726		sectors = transport_get_sectors_6(cdb);
 727		cmd->t_task_lba = transport_lba_21(cdb);
 728		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 729		cmd->execute_rw = ops->execute_rw;
 730		cmd->execute_cmd = sbc_execute_rw;
 731		break;
 732	case WRITE_10:
 733	case WRITE_VERIFY:
 734		sectors = transport_get_sectors_10(cdb);
 735		cmd->t_task_lba = transport_lba_32(cdb);
 736
 737		if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 738			return TCM_UNSUPPORTED_SCSI_OPCODE;
 
 
 
 
 739
 740		if (cdb[1] & 0x8)
 741			cmd->se_cmd_flags |= SCF_FUA;
 742		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 743		cmd->execute_rw = ops->execute_rw;
 744		cmd->execute_cmd = sbc_execute_rw;
 745		break;
 746	case WRITE_12:
 747		sectors = transport_get_sectors_12(cdb);
 748		cmd->t_task_lba = transport_lba_32(cdb);
 749
 750		if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 751			return TCM_UNSUPPORTED_SCSI_OPCODE;
 
 
 
 
 752
 753		if (cdb[1] & 0x8)
 754			cmd->se_cmd_flags |= SCF_FUA;
 755		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 756		cmd->execute_rw = ops->execute_rw;
 757		cmd->execute_cmd = sbc_execute_rw;
 758		break;
 759	case WRITE_16:
 
 760		sectors = transport_get_sectors_16(cdb);
 761		cmd->t_task_lba = transport_lba_64(cdb);
 762
 763		if (!sbc_check_prot(dev, cmd, cdb, sectors, true))
 764			return TCM_UNSUPPORTED_SCSI_OPCODE;
 765
 766		if (cdb[1] & 0x8)
 767			cmd->se_cmd_flags |= SCF_FUA;
 768		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 769		cmd->execute_rw = ops->execute_rw;
 770		cmd->execute_cmd = sbc_execute_rw;
 771		break;
 772	case XDWRITEREAD_10:
 773		if (cmd->data_direction != DMA_TO_DEVICE ||
 774		    !(cmd->se_cmd_flags & SCF_BIDI))
 775			return TCM_INVALID_CDB_FIELD;
 776		sectors = transport_get_sectors_10(cdb);
 777
 778		cmd->t_task_lba = transport_lba_32(cdb);
 779		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 780
 781		/*
 782		 * Setup BIDI XOR callback to be run after I/O completion.
 783		 */
 784		cmd->execute_rw = ops->execute_rw;
 785		cmd->execute_cmd = sbc_execute_rw;
 786		cmd->transport_complete_callback = &xdreadwrite_callback;
 787		if (cdb[1] & 0x8)
 788			cmd->se_cmd_flags |= SCF_FUA;
 789		break;
 790	case VARIABLE_LENGTH_CMD:
 791	{
 792		u16 service_action = get_unaligned_be16(&cdb[8]);
 793		switch (service_action) {
 794		case XDWRITEREAD_32:
 795			sectors = transport_get_sectors_32(cdb);
 796
 797			/*
 798			 * Use WRITE_32 and READ_32 opcodes for the emulated
 799			 * XDWRITE_READ_32 logic.
 800			 */
 801			cmd->t_task_lba = transport_lba_64_ext(cdb);
 802			cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
 803
 804			/*
 805			 * Setup BIDI XOR callback to be run during after I/O
 806			 * completion.
 807			 */
 808			cmd->execute_rw = ops->execute_rw;
 809			cmd->execute_cmd = sbc_execute_rw;
 810			cmd->transport_complete_callback = &xdreadwrite_callback;
 811			if (cdb[1] & 0x8)
 812				cmd->se_cmd_flags |= SCF_FUA;
 813			break;
 814		case WRITE_SAME_32:
 815			sectors = transport_get_sectors_32(cdb);
 816			if (!sectors) {
 817				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 818				       " supported\n");
 819				return TCM_INVALID_CDB_FIELD;
 820			}
 821
 822			size = sbc_get_size(cmd, 1);
 823			cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
 824
 825			ret = sbc_setup_write_same(cmd, &cdb[10], ops);
 826			if (ret)
 827				return ret;
 828			break;
 829		default:
 830			pr_err("VARIABLE_LENGTH_CMD service action"
 831				" 0x%04x not supported\n", service_action);
 832			return TCM_UNSUPPORTED_SCSI_OPCODE;
 833		}
 834		break;
 835	}
 836	case COMPARE_AND_WRITE:
 
 
 
 
 
 
 
 837		sectors = cdb[13];
 838		/*
 839		 * Currently enforce COMPARE_AND_WRITE for a single sector
 840		 */
 841		if (sectors > 1) {
 842			pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
 843			       " than 1\n", sectors);
 844			return TCM_INVALID_CDB_FIELD;
 845		}
 
 
 
 846		/*
 847		 * Double size because we have two buffers, note that
 848		 * zero is not an error..
 849		 */
 850		size = 2 * sbc_get_size(cmd, sectors);
 851		cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
 852		cmd->t_task_nolb = sectors;
 853		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
 854		cmd->execute_rw = ops->execute_rw;
 855		cmd->execute_cmd = sbc_compare_and_write;
 856		cmd->transport_complete_callback = compare_and_write_callback;
 857		break;
 858	case READ_CAPACITY:
 859		size = READ_CAP_LEN;
 860		cmd->execute_cmd = sbc_emulate_readcapacity;
 861		break;
 862	case SERVICE_ACTION_IN:
 863		switch (cmd->t_task_cdb[1] & 0x1f) {
 864		case SAI_READ_CAPACITY_16:
 865			cmd->execute_cmd = sbc_emulate_readcapacity_16;
 866			break;
 867		case SAI_REPORT_REFERRALS:
 868			cmd->execute_cmd = target_emulate_report_referrals;
 869			break;
 870		default:
 871			pr_err("Unsupported SA: 0x%02x\n",
 872				cmd->t_task_cdb[1] & 0x1f);
 873			return TCM_INVALID_CDB_FIELD;
 874		}
 875		size = (cdb[10] << 24) | (cdb[11] << 16) |
 876		       (cdb[12] << 8) | cdb[13];
 877		break;
 878	case SYNCHRONIZE_CACHE:
 879	case SYNCHRONIZE_CACHE_16:
 880		if (!ops->execute_sync_cache) {
 881			size = 0;
 882			cmd->execute_cmd = sbc_emulate_noop;
 883			break;
 884		}
 885
 886		/*
 887		 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
 888		 */
 889		if (cdb[0] == SYNCHRONIZE_CACHE) {
 890			sectors = transport_get_sectors_10(cdb);
 891			cmd->t_task_lba = transport_lba_32(cdb);
 892		} else {
 893			sectors = transport_get_sectors_16(cdb);
 894			cmd->t_task_lba = transport_lba_64(cdb);
 895		}
 896
 897		size = sbc_get_size(cmd, sectors);
 898
 899		/*
 900		 * Check to ensure that LBA + Range does not exceed past end of
 901		 * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
 902		 */
 903		if (cmd->t_task_lba || sectors) {
 904			if (sbc_check_valid_sectors(cmd) < 0)
 905				return TCM_ADDRESS_OUT_OF_RANGE;
 906		}
 907		cmd->execute_cmd = ops->execute_sync_cache;
 
 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		size = 0;
 
 
 
 
 
 
 
 950		cmd->execute_cmd = sbc_emulate_noop;
 951		break;
 952	case REZERO_UNIT:
 953	case SEEK_6:
 954	case SEEK_10:
 955		/*
 956		 * There are still clients out there which use these old SCSI-2
 957		 * commands. This mainly happens when running VMs with legacy
 958		 * guest systems, connected via SCSI command pass-through to
 959		 * iSCSI targets. Make them happy and return status GOOD.
 960		 */
 961		size = 0;
 962		cmd->execute_cmd = sbc_emulate_noop;
 963		break;
 
 
 
 
 964	default:
 965		ret = spc_parse_cdb(cmd, &size);
 966		if (ret)
 967			return ret;
 968	}
 969
 970	/* reject any command that we don't have a handler for */
 971	if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
 972		return TCM_UNSUPPORTED_SCSI_OPCODE;
 973
 974	if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
 975		unsigned long long end_lba;
 976
 977		if (sectors > dev->dev_attrib.fabric_max_sectors) {
 978			printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
 979				" big sectors %u exceeds fabric_max_sectors:"
 980				" %u\n", cdb[0], sectors,
 981				dev->dev_attrib.fabric_max_sectors);
 982			return TCM_INVALID_CDB_FIELD;
 983		}
 984		if (sectors > dev->dev_attrib.hw_max_sectors) {
 985			printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
 986				" big sectors %u exceeds backend hw_max_sectors:"
 987				" %u\n", cdb[0], sectors,
 988				dev->dev_attrib.hw_max_sectors);
 989			return TCM_INVALID_CDB_FIELD;
 990		}
 991
 992		end_lba = dev->transport->get_blocks(dev) + 1;
 993		if (cmd->t_task_lba + sectors > end_lba) {
 
 994			pr_err("cmd exceeds last lba %llu "
 995				"(lba %llu, sectors %u)\n",
 996				end_lba, cmd->t_task_lba, sectors);
 997			return TCM_ADDRESS_OUT_OF_RANGE;
 998		}
 999
1000		if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1001			size = sbc_get_size(cmd, sectors);
1002	}
1003
1004	return target_cmd_size_check(cmd, size);
1005}
1006EXPORT_SYMBOL(sbc_parse_cdb);
1007
1008u32 sbc_get_device_type(struct se_device *dev)
1009{
1010	return TYPE_DISK;
1011}
1012EXPORT_SYMBOL(sbc_get_device_type);
1013
1014sense_reason_t
1015sbc_execute_unmap(struct se_cmd *cmd,
1016	sense_reason_t (*do_unmap_fn)(struct se_cmd *, void *,
1017				      sector_t, sector_t),
1018	void *priv)
1019{
 
1020	struct se_device *dev = cmd->se_dev;
1021	unsigned char *buf, *ptr = NULL;
1022	sector_t lba;
1023	int size;
1024	u32 range;
1025	sense_reason_t ret = 0;
1026	int dl, bd_dl;
1027
1028	/* We never set ANC_SUP */
1029	if (cmd->t_task_cdb[1])
1030		return TCM_INVALID_CDB_FIELD;
1031
1032	if (cmd->data_length == 0) {
1033		target_complete_cmd(cmd, SAM_STAT_GOOD);
1034		return 0;
1035	}
1036
1037	if (cmd->data_length < 8) {
1038		pr_warn("UNMAP parameter list length %u too small\n",
1039			cmd->data_length);
1040		return TCM_PARAMETER_LIST_LENGTH_ERROR;
1041	}
1042
1043	buf = transport_kmap_data_sg(cmd);
1044	if (!buf)
1045		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1046
1047	dl = get_unaligned_be16(&buf[0]);
1048	bd_dl = get_unaligned_be16(&buf[2]);
1049
1050	size = cmd->data_length - 8;
1051	if (bd_dl > size)
1052		pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1053			cmd->data_length, bd_dl);
1054	else
1055		size = bd_dl;
1056
1057	if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1058		ret = TCM_INVALID_PARAMETER_LIST;
1059		goto err;
1060	}
1061
1062	/* First UNMAP block descriptor starts at 8 byte offset */
1063	ptr = &buf[8];
1064	pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1065		" ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1066
1067	while (size >= 16) {
1068		lba = get_unaligned_be64(&ptr[0]);
1069		range = get_unaligned_be32(&ptr[8]);
1070		pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1071				 (unsigned long long)lba, range);
1072
1073		if (range > dev->dev_attrib.max_unmap_lba_count) {
1074			ret = TCM_INVALID_PARAMETER_LIST;
1075			goto err;
1076		}
1077
1078		if (lba + range > dev->transport->get_blocks(dev) + 1) {
1079			ret = TCM_ADDRESS_OUT_OF_RANGE;
1080			goto err;
1081		}
1082
1083		ret = do_unmap_fn(cmd, priv, lba, range);
1084		if (ret)
1085			goto err;
 
 
1086
1087		ptr += 16;
1088		size -= 16;
1089	}
1090
1091err:
1092	transport_kunmap_data_sg(cmd);
1093	if (!ret)
1094		target_complete_cmd(cmd, GOOD);
1095	return ret;
1096}
1097EXPORT_SYMBOL(sbc_execute_unmap);
1098
1099void
1100sbc_dif_generate(struct se_cmd *cmd)
1101{
1102	struct se_device *dev = cmd->se_dev;
1103	struct se_dif_v1_tuple *sdt;
1104	struct scatterlist *dsg, *psg = cmd->t_prot_sg;
1105	sector_t sector = cmd->t_task_lba;
1106	void *daddr, *paddr;
1107	int i, j, offset = 0;
 
1108
1109	for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
 
1110		daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1111		paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1112
1113		for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1114
1115			if (offset >= psg->length) {
1116				kunmap_atomic(paddr);
1117				psg = sg_next(psg);
1118				paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1119				offset = 0;
 
 
 
 
 
 
 
 
 
 
1120			}
1121
1122			sdt = paddr + offset;
1123			sdt->guard_tag = cpu_to_be16(crc_t10dif(daddr + j,
1124						dev->dev_attrib.block_size));
1125			if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT)
1126				sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1127			sdt->app_tag = 0;
1128
1129			pr_debug("DIF WRITE INSERT sector: %llu guard_tag: 0x%04x"
1130				 " app_tag: 0x%04x ref_tag: %u\n",
1131				 (unsigned long long)sector, sdt->guard_tag,
1132				 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
 
 
1133
1134			sector++;
1135			offset += sizeof(struct se_dif_v1_tuple);
1136		}
1137
1138		kunmap_atomic(paddr);
1139		kunmap_atomic(daddr);
1140	}
1141}
1142
1143static sense_reason_t
1144sbc_dif_v1_verify(struct se_device *dev, struct se_dif_v1_tuple *sdt,
1145		  const void *p, sector_t sector, unsigned int ei_lba)
1146{
1147	int block_size = dev->dev_attrib.block_size;
1148	__be16 csum;
1149
1150	csum = cpu_to_be16(crc_t10dif(p, block_size));
 
 
 
1151
1152	if (sdt->guard_tag != csum) {
1153		pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1154			" csum 0x%04x\n", (unsigned long long)sector,
1155			be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1156		return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1157	}
1158
1159	if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT &&
 
 
 
 
1160	    be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1161		pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1162		       " sector MSB: 0x%08x\n", (unsigned long long)sector,
1163		       be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1164		return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1165	}
1166
1167	if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE2_PROT &&
1168	    be32_to_cpu(sdt->ref_tag) != ei_lba) {
1169		pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1170		       " ei_lba: 0x%08x\n", (unsigned long long)sector,
1171			be32_to_cpu(sdt->ref_tag), ei_lba);
1172		return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1173	}
1174
1175	return 0;
1176}
1177
1178static void
1179sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1180		  struct scatterlist *sg, int sg_off)
1181{
1182	struct se_device *dev = cmd->se_dev;
1183	struct scatterlist *psg;
1184	void *paddr, *addr;
1185	unsigned int i, len, left;
1186	unsigned int offset = sg_off;
1187
 
 
 
1188	left = sectors * dev->prot_length;
1189
1190	for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1191		unsigned int psg_len, copied = 0;
1192
1193		paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1194		psg_len = min(left, psg->length);
1195		while (psg_len) {
1196			len = min(psg_len, sg->length - offset);
1197			addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1198
1199			if (read)
1200				memcpy(paddr + copied, addr, len);
1201			else
1202				memcpy(addr, paddr + copied, len);
1203
1204			left -= len;
1205			offset += len;
1206			copied += len;
1207			psg_len -= len;
1208
 
 
1209			if (offset >= sg->length) {
1210				sg = sg_next(sg);
1211				offset = 0;
1212			}
1213			kunmap_atomic(addr);
1214		}
1215		kunmap_atomic(paddr);
1216	}
1217}
 
1218
1219sense_reason_t
1220sbc_dif_verify_write(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1221		     unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1222{
1223	struct se_device *dev = cmd->se_dev;
1224	struct se_dif_v1_tuple *sdt;
1225	struct scatterlist *dsg, *psg = cmd->t_prot_sg;
1226	sector_t sector = start;
1227	void *daddr, *paddr;
1228	int i, j, offset = 0;
1229	sense_reason_t rc;
 
 
1230
1231	for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
 
1232		daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1233		paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1234
1235		for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1236
1237			if (offset >= psg->length) {
1238				kunmap_atomic(paddr);
1239				psg = sg_next(psg);
1240				paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1241				offset = 0;
 
 
 
 
 
 
 
 
 
 
1242			}
1243
1244			sdt = paddr + offset;
1245
1246			pr_debug("DIF WRITE sector: %llu guard_tag: 0x%04x"
1247				 " app_tag: 0x%04x ref_tag: %u\n",
1248				 (unsigned long long)sector, sdt->guard_tag,
1249				 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1250
1251			rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
1252					       ei_lba);
1253			if (rc) {
1254				kunmap_atomic(paddr);
1255				kunmap_atomic(daddr);
1256				cmd->bad_sector = sector;
1257				return rc;
1258			}
1259
1260			sector++;
1261			ei_lba++;
1262			offset += sizeof(struct se_dif_v1_tuple);
1263		}
1264
1265		kunmap_atomic(paddr);
1266		kunmap_atomic(daddr);
1267	}
1268	sbc_dif_copy_prot(cmd, sectors, false, sg, sg_off);
1269
1270	return 0;
1271}
1272EXPORT_SYMBOL(sbc_dif_verify_write);
1273
1274static sense_reason_t
1275__sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1276		      unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1277{
1278	struct se_device *dev = cmd->se_dev;
1279	struct se_dif_v1_tuple *sdt;
1280	struct scatterlist *dsg, *psg = sg;
1281	sector_t sector = start;
1282	void *daddr, *paddr;
1283	int i, j, offset = sg_off;
1284	sense_reason_t rc;
1285
1286	for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
1287		daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1288		paddr = kmap_atomic(sg_page(psg)) + sg->offset;
1289
1290		for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
1291
1292			if (offset >= psg->length) {
1293				kunmap_atomic(paddr);
1294				psg = sg_next(psg);
1295				paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1296				offset = 0;
1297			}
1298
1299			sdt = paddr + offset;
1300
1301			pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1302				 " app_tag: 0x%04x ref_tag: %u\n",
1303				 (unsigned long long)sector, sdt->guard_tag,
1304				 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1305
1306			if (sdt->app_tag == cpu_to_be16(0xffff)) {
1307				sector++;
1308				offset += sizeof(struct se_dif_v1_tuple);
1309				continue;
 
 
 
1310			}
1311
1312			rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
1313					       ei_lba);
1314			if (rc) {
1315				kunmap_atomic(paddr);
1316				kunmap_atomic(daddr);
1317				cmd->bad_sector = sector;
1318				return rc;
1319			}
1320
1321			sector++;
1322			ei_lba++;
1323			offset += sizeof(struct se_dif_v1_tuple);
1324		}
1325
1326		kunmap_atomic(paddr);
1327		kunmap_atomic(daddr);
 
1328	}
1329
1330	return 0;
1331}
1332
1333sense_reason_t
1334sbc_dif_read_strip(struct se_cmd *cmd)
1335{
1336	struct se_device *dev = cmd->se_dev;
1337	u32 sectors = cmd->prot_length / dev->prot_length;
1338
1339	return __sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0,
1340				     cmd->t_prot_sg, 0);
1341}
1342
1343sense_reason_t
1344sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1345		    unsigned int ei_lba, struct scatterlist *sg, int sg_off)
1346{
1347	sense_reason_t rc;
1348
1349	rc = __sbc_dif_verify_read(cmd, start, sectors, ei_lba, sg, sg_off);
1350	if (rc)
1351		return rc;
1352
1353	sbc_dif_copy_prot(cmd, sectors, true, sg, sg_off);
1354	return 0;
1355}
1356EXPORT_SYMBOL(sbc_dif_verify_read);