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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * SCSI Primary Commands (SPC) 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 <asm/unaligned.h>
  13
  14#include <scsi/scsi_proto.h>
  15#include <scsi/scsi_common.h>
  16#include <scsi/scsi_tcq.h>
  17
  18#include <target/target_core_base.h>
  19#include <target/target_core_backend.h>
  20#include <target/target_core_fabric.h>
  21
  22#include "target_core_internal.h"
  23#include "target_core_alua.h"
  24#include "target_core_pr.h"
  25#include "target_core_ua.h"
  26#include "target_core_xcopy.h"
  27
  28static void spc_fill_alua_data(struct se_lun *lun, unsigned char *buf)
  29{
  30	struct t10_alua_tg_pt_gp *tg_pt_gp;
  31
  32	/*
  33	 * Set SCCS for MAINTENANCE_IN + REPORT_TARGET_PORT_GROUPS.
  34	 */
  35	buf[5]	= 0x80;
  36
  37	/*
  38	 * Set TPGS field for explicit and/or implicit ALUA access type
  39	 * and opteration.
  40	 *
  41	 * See spc4r17 section 6.4.2 Table 135
  42	 */
  43	spin_lock(&lun->lun_tg_pt_gp_lock);
  44	tg_pt_gp = lun->lun_tg_pt_gp;
  45	if (tg_pt_gp)
  46		buf[5] |= tg_pt_gp->tg_pt_gp_alua_access_type;
  47	spin_unlock(&lun->lun_tg_pt_gp_lock);
  48}
  49
  50static u16
  51spc_find_scsi_transport_vd(int proto_id)
  52{
  53	switch (proto_id) {
  54	case SCSI_PROTOCOL_FCP:
  55		return SCSI_VERSION_DESCRIPTOR_FCP4;
  56	case SCSI_PROTOCOL_ISCSI:
  57		return SCSI_VERSION_DESCRIPTOR_ISCSI;
  58	case SCSI_PROTOCOL_SAS:
  59		return SCSI_VERSION_DESCRIPTOR_SAS3;
  60	case SCSI_PROTOCOL_SBP:
  61		return SCSI_VERSION_DESCRIPTOR_SBP3;
  62	case SCSI_PROTOCOL_SRP:
  63		return SCSI_VERSION_DESCRIPTOR_SRP;
  64	default:
  65		pr_warn("Cannot find VERSION DESCRIPTOR value for unknown SCSI"
  66			" transport PROTOCOL IDENTIFIER %#x\n", proto_id);
  67		return 0;
  68	}
  69}
  70
  71sense_reason_t
  72spc_emulate_inquiry_std(struct se_cmd *cmd, unsigned char *buf)
  73{
  74	struct se_lun *lun = cmd->se_lun;
  75	struct se_portal_group *tpg = lun->lun_tpg;
  76	struct se_device *dev = cmd->se_dev;
  77	struct se_session *sess = cmd->se_sess;
  78
  79	/* Set RMB (removable media) for tape devices */
  80	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
  81		buf[1] = 0x80;
  82
  83	buf[2] = 0x06; /* SPC-4 */
  84
  85	/*
  86	 * NORMACA and HISUP = 0, RESPONSE DATA FORMAT = 2
  87	 *
  88	 * SPC4 says:
  89	 *   A RESPONSE DATA FORMAT field set to 2h indicates that the
  90	 *   standard INQUIRY data is in the format defined in this
  91	 *   standard. Response data format values less than 2h are
  92	 *   obsolete. Response data format values greater than 2h are
  93	 *   reserved.
  94	 */
  95	buf[3] = 2;
  96
  97	/*
  98	 * Enable SCCS and TPGS fields for Emulated ALUA
  99	 */
 100	spc_fill_alua_data(lun, buf);
 101
 102	/*
 103	 * Set Third-Party Copy (3PC) bit to indicate support for EXTENDED_COPY
 104	 */
 105	if (dev->dev_attrib.emulate_3pc)
 106		buf[5] |= 0x8;
 107	/*
 108	 * Set Protection (PROTECT) bit when DIF has been enabled on the
 109	 * device, and the fabric supports VERIFY + PASS.  Also report
 110	 * PROTECT=1 if sess_prot_type has been configured to allow T10-PI
 111	 * to unprotected devices.
 112	 */
 113	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
 114		if (dev->dev_attrib.pi_prot_type || cmd->se_sess->sess_prot_type)
 115			buf[5] |= 0x1;
 116	}
 117
 118	buf[7] = 0x2; /* CmdQue=1 */
 119
 120	/*
 121	 * ASCII data fields described as being left-aligned shall have any
 122	 * unused bytes at the end of the field (i.e., highest offset) and the
 123	 * unused bytes shall be filled with ASCII space characters (20h).
 124	 */
 125	memset(&buf[8], 0x20,
 126	       INQUIRY_VENDOR_LEN + INQUIRY_MODEL_LEN + INQUIRY_REVISION_LEN);
 127	memcpy(&buf[8], dev->t10_wwn.vendor,
 128	       strnlen(dev->t10_wwn.vendor, INQUIRY_VENDOR_LEN));
 129	memcpy(&buf[16], dev->t10_wwn.model,
 130	       strnlen(dev->t10_wwn.model, INQUIRY_MODEL_LEN));
 131	memcpy(&buf[32], dev->t10_wwn.revision,
 132	       strnlen(dev->t10_wwn.revision, INQUIRY_REVISION_LEN));
 133
 134	/*
 135	 * Set the VERSION DESCRIPTOR fields
 136	 */
 137	put_unaligned_be16(SCSI_VERSION_DESCRIPTOR_SAM5, &buf[58]);
 138	put_unaligned_be16(spc_find_scsi_transport_vd(tpg->proto_id), &buf[60]);
 139	put_unaligned_be16(SCSI_VERSION_DESCRIPTOR_SPC4, &buf[62]);
 140	if (cmd->se_dev->transport->get_device_type(dev) == TYPE_DISK)
 141		put_unaligned_be16(SCSI_VERSION_DESCRIPTOR_SBC3, &buf[64]);
 142
 143	buf[4] = 91; /* Set additional length to 91 */
 144
 145	return 0;
 146}
 147EXPORT_SYMBOL(spc_emulate_inquiry_std);
 148
 149/* unit serial number */
 150static sense_reason_t
 151spc_emulate_evpd_80(struct se_cmd *cmd, unsigned char *buf)
 152{
 153	struct se_device *dev = cmd->se_dev;
 154	u16 len;
 155
 156	if (dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL) {
 157		len = sprintf(&buf[4], "%s", dev->t10_wwn.unit_serial);
 158		len++; /* Extra Byte for NULL Terminator */
 159		buf[3] = len;
 160	}
 161	return 0;
 162}
 163
 164/*
 165 * Generate NAA IEEE Registered Extended designator
 166 */
 167void spc_gen_naa_6h_vendor_specific(struct se_device *dev,
 168				    unsigned char *buf)
 169{
 170	unsigned char *p = &dev->t10_wwn.unit_serial[0];
 171	u32 company_id = dev->t10_wwn.company_id;
 172	int cnt, off = 0;
 173	bool next = true;
 174
 175	/*
 176	 * Start NAA IEEE Registered Extended Identifier/Designator
 177	 */
 178	buf[off] = 0x6 << 4;
 179
 180	/* IEEE COMPANY_ID */
 181	buf[off++] |= (company_id >> 20) & 0xf;
 182	buf[off++] = (company_id >> 12) & 0xff;
 183	buf[off++] = (company_id >> 4) & 0xff;
 184	buf[off] = (company_id & 0xf) << 4;
 185
 186	/*
 187	 * Generate up to 36 bits of VENDOR SPECIFIC IDENTIFIER starting on
 188	 * byte 3 bit 3-0 for NAA IEEE Registered Extended DESIGNATOR field
 189	 * format, followed by 64 bits of VENDOR SPECIFIC IDENTIFIER EXTENSION
 190	 * to complete the payload.  These are based from VPD=0x80 PRODUCT SERIAL
 191	 * NUMBER set via vpd_unit_serial in target_core_configfs.c to ensure
 192	 * per device uniqeness.
 193	 */
 194	for (cnt = off + 13; *p && off < cnt; p++) {
 195		int val = hex_to_bin(*p);
 196
 197		if (val < 0)
 198			continue;
 199
 200		if (next) {
 201			next = false;
 202			buf[off++] |= val;
 203		} else {
 204			next = true;
 205			buf[off] = val << 4;
 206		}
 207	}
 208}
 209
 210/*
 211 * Device identification VPD, for a complete list of
 212 * DESIGNATOR TYPEs see spc4r17 Table 459.
 213 */
 214sense_reason_t
 215spc_emulate_evpd_83(struct se_cmd *cmd, unsigned char *buf)
 216{
 217	struct se_device *dev = cmd->se_dev;
 218	struct se_lun *lun = cmd->se_lun;
 219	struct se_portal_group *tpg = NULL;
 220	struct t10_alua_lu_gp_member *lu_gp_mem;
 221	struct t10_alua_tg_pt_gp *tg_pt_gp;
 222	unsigned char *prod = &dev->t10_wwn.model[0];
 223	u32 prod_len;
 224	u32 unit_serial_len, off = 0;
 225	u16 len = 0, id_len;
 226
 227	off = 4;
 228
 229	/*
 230	 * NAA IEEE Registered Extended Assigned designator format, see
 231	 * spc4r17 section 7.7.3.6.5
 232	 *
 233	 * We depend upon a target_core_mod/ConfigFS provided
 234	 * /sys/kernel/config/target/core/$HBA/$DEV/wwn/vpd_unit_serial
 235	 * value in order to return the NAA id.
 236	 */
 237	if (!(dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL))
 238		goto check_t10_vend_desc;
 239
 240	/* CODE SET == Binary */
 241	buf[off++] = 0x1;
 242
 243	/* Set ASSOCIATION == addressed logical unit: 0)b */
 244	buf[off] = 0x00;
 245
 246	/* Identifier/Designator type == NAA identifier */
 247	buf[off++] |= 0x3;
 248	off++;
 249
 250	/* Identifier/Designator length */
 251	buf[off++] = 0x10;
 252
 253	/* NAA IEEE Registered Extended designator */
 254	spc_gen_naa_6h_vendor_specific(dev, &buf[off]);
 255
 256	len = 20;
 257	off = (len + 4);
 258
 259check_t10_vend_desc:
 260	/*
 261	 * T10 Vendor Identifier Page, see spc4r17 section 7.7.3.4
 262	 */
 263	id_len = 8; /* For Vendor field */
 264	prod_len = 4; /* For VPD Header */
 265	prod_len += 8; /* For Vendor field */
 266	prod_len += strlen(prod);
 267	prod_len++; /* For : */
 268
 269	if (dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL) {
 270		unit_serial_len = strlen(&dev->t10_wwn.unit_serial[0]);
 271		unit_serial_len++; /* For NULL Terminator */
 272
 273		id_len += sprintf(&buf[off+12], "%s:%s", prod,
 274				&dev->t10_wwn.unit_serial[0]);
 275	}
 276	buf[off] = 0x2; /* ASCII */
 277	buf[off+1] = 0x1; /* T10 Vendor ID */
 278	buf[off+2] = 0x0;
 279	/* left align Vendor ID and pad with spaces */
 280	memset(&buf[off+4], 0x20, INQUIRY_VENDOR_LEN);
 281	memcpy(&buf[off+4], dev->t10_wwn.vendor,
 282	       strnlen(dev->t10_wwn.vendor, INQUIRY_VENDOR_LEN));
 283	/* Extra Byte for NULL Terminator */
 284	id_len++;
 285	/* Identifier Length */
 286	buf[off+3] = id_len;
 287	/* Header size for Designation descriptor */
 288	len += (id_len + 4);
 289	off += (id_len + 4);
 290
 291	if (1) {
 292		struct t10_alua_lu_gp *lu_gp;
 293		u32 padding, scsi_name_len, scsi_target_len;
 294		u16 lu_gp_id = 0;
 295		u16 tg_pt_gp_id = 0;
 296		u16 tpgt;
 297
 298		tpg = lun->lun_tpg;
 299		/*
 300		 * Relative target port identifer, see spc4r17
 301		 * section 7.7.3.7
 302		 *
 303		 * Get the PROTOCOL IDENTIFIER as defined by spc4r17
 304		 * section 7.5.1 Table 362
 305		 */
 306		buf[off] = tpg->proto_id << 4;
 307		buf[off++] |= 0x1; /* CODE SET == Binary */
 308		buf[off] = 0x80; /* Set PIV=1 */
 309		/* Set ASSOCIATION == target port: 01b */
 310		buf[off] |= 0x10;
 311		/* DESIGNATOR TYPE == Relative target port identifer */
 312		buf[off++] |= 0x4;
 313		off++; /* Skip over Reserved */
 314		buf[off++] = 4; /* DESIGNATOR LENGTH */
 315		/* Skip over Obsolete field in RTPI payload
 316		 * in Table 472 */
 317		off += 2;
 318		put_unaligned_be16(lun->lun_rtpi, &buf[off]);
 319		off += 2;
 320		len += 8; /* Header size + Designation descriptor */
 321		/*
 322		 * Target port group identifier, see spc4r17
 323		 * section 7.7.3.8
 324		 *
 325		 * Get the PROTOCOL IDENTIFIER as defined by spc4r17
 326		 * section 7.5.1 Table 362
 327		 */
 328		spin_lock(&lun->lun_tg_pt_gp_lock);
 329		tg_pt_gp = lun->lun_tg_pt_gp;
 330		if (!tg_pt_gp) {
 331			spin_unlock(&lun->lun_tg_pt_gp_lock);
 332			goto check_lu_gp;
 333		}
 334		tg_pt_gp_id = tg_pt_gp->tg_pt_gp_id;
 335		spin_unlock(&lun->lun_tg_pt_gp_lock);
 336
 337		buf[off] = tpg->proto_id << 4;
 338		buf[off++] |= 0x1; /* CODE SET == Binary */
 339		buf[off] = 0x80; /* Set PIV=1 */
 340		/* Set ASSOCIATION == target port: 01b */
 341		buf[off] |= 0x10;
 342		/* DESIGNATOR TYPE == Target port group identifier */
 343		buf[off++] |= 0x5;
 344		off++; /* Skip over Reserved */
 345		buf[off++] = 4; /* DESIGNATOR LENGTH */
 346		off += 2; /* Skip over Reserved Field */
 347		put_unaligned_be16(tg_pt_gp_id, &buf[off]);
 348		off += 2;
 349		len += 8; /* Header size + Designation descriptor */
 350		/*
 351		 * Logical Unit Group identifier, see spc4r17
 352		 * section 7.7.3.8
 353		 */
 354check_lu_gp:
 355		lu_gp_mem = dev->dev_alua_lu_gp_mem;
 356		if (!lu_gp_mem)
 357			goto check_scsi_name;
 358
 359		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
 360		lu_gp = lu_gp_mem->lu_gp;
 361		if (!lu_gp) {
 362			spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
 363			goto check_scsi_name;
 364		}
 365		lu_gp_id = lu_gp->lu_gp_id;
 366		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
 367
 368		buf[off++] |= 0x1; /* CODE SET == Binary */
 369		/* DESIGNATOR TYPE == Logical Unit Group identifier */
 370		buf[off++] |= 0x6;
 371		off++; /* Skip over Reserved */
 372		buf[off++] = 4; /* DESIGNATOR LENGTH */
 373		off += 2; /* Skip over Reserved Field */
 374		put_unaligned_be16(lu_gp_id, &buf[off]);
 375		off += 2;
 376		len += 8; /* Header size + Designation descriptor */
 377		/*
 378		 * SCSI name string designator, see spc4r17
 379		 * section 7.7.3.11
 380		 *
 381		 * Get the PROTOCOL IDENTIFIER as defined by spc4r17
 382		 * section 7.5.1 Table 362
 383		 */
 384check_scsi_name:
 385		buf[off] = tpg->proto_id << 4;
 386		buf[off++] |= 0x3; /* CODE SET == UTF-8 */
 387		buf[off] = 0x80; /* Set PIV=1 */
 388		/* Set ASSOCIATION == target port: 01b */
 389		buf[off] |= 0x10;
 390		/* DESIGNATOR TYPE == SCSI name string */
 391		buf[off++] |= 0x8;
 392		off += 2; /* Skip over Reserved and length */
 393		/*
 394		 * SCSI name string identifer containing, $FABRIC_MOD
 395		 * dependent information.  For LIO-Target and iSCSI
 396		 * Target Port, this means "<iSCSI name>,t,0x<TPGT> in
 397		 * UTF-8 encoding.
 398		 */
 399		tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
 400		scsi_name_len = sprintf(&buf[off], "%s,t,0x%04x",
 401					tpg->se_tpg_tfo->tpg_get_wwn(tpg), tpgt);
 402		scsi_name_len += 1 /* Include  NULL terminator */;
 403		/*
 404		 * The null-terminated, null-padded (see 4.4.2) SCSI
 405		 * NAME STRING field contains a UTF-8 format string.
 406		 * The number of bytes in the SCSI NAME STRING field
 407		 * (i.e., the value in the DESIGNATOR LENGTH field)
 408		 * shall be no larger than 256 and shall be a multiple
 409		 * of four.
 410		 */
 411		padding = ((-scsi_name_len) & 3);
 412		if (padding)
 413			scsi_name_len += padding;
 414		if (scsi_name_len > 256)
 415			scsi_name_len = 256;
 416
 417		buf[off-1] = scsi_name_len;
 418		off += scsi_name_len;
 419		/* Header size + Designation descriptor */
 420		len += (scsi_name_len + 4);
 421
 422		/*
 423		 * Target device designator
 424		 */
 425		buf[off] = tpg->proto_id << 4;
 426		buf[off++] |= 0x3; /* CODE SET == UTF-8 */
 427		buf[off] = 0x80; /* Set PIV=1 */
 428		/* Set ASSOCIATION == target device: 10b */
 429		buf[off] |= 0x20;
 430		/* DESIGNATOR TYPE == SCSI name string */
 431		buf[off++] |= 0x8;
 432		off += 2; /* Skip over Reserved and length */
 433		/*
 434		 * SCSI name string identifer containing, $FABRIC_MOD
 435		 * dependent information.  For LIO-Target and iSCSI
 436		 * Target Port, this means "<iSCSI name>" in
 437		 * UTF-8 encoding.
 438		 */
 439		scsi_target_len = sprintf(&buf[off], "%s",
 440					  tpg->se_tpg_tfo->tpg_get_wwn(tpg));
 441		scsi_target_len += 1 /* Include  NULL terminator */;
 442		/*
 443		 * The null-terminated, null-padded (see 4.4.2) SCSI
 444		 * NAME STRING field contains a UTF-8 format string.
 445		 * The number of bytes in the SCSI NAME STRING field
 446		 * (i.e., the value in the DESIGNATOR LENGTH field)
 447		 * shall be no larger than 256 and shall be a multiple
 448		 * of four.
 449		 */
 450		padding = ((-scsi_target_len) & 3);
 451		if (padding)
 452			scsi_target_len += padding;
 453		if (scsi_target_len > 256)
 454			scsi_target_len = 256;
 455
 456		buf[off-1] = scsi_target_len;
 457		off += scsi_target_len;
 458
 459		/* Header size + Designation descriptor */
 460		len += (scsi_target_len + 4);
 461	}
 462	put_unaligned_be16(len, &buf[2]); /* Page Length for VPD 0x83 */
 463	return 0;
 464}
 465EXPORT_SYMBOL(spc_emulate_evpd_83);
 466
 467/* Extended INQUIRY Data VPD Page */
 468static sense_reason_t
 469spc_emulate_evpd_86(struct se_cmd *cmd, unsigned char *buf)
 470{
 471	struct se_device *dev = cmd->se_dev;
 472	struct se_session *sess = cmd->se_sess;
 473
 474	buf[3] = 0x3c;
 475	/*
 476	 * Set GRD_CHK + REF_CHK for TYPE1 protection, or GRD_CHK
 477	 * only for TYPE3 protection.
 478	 */
 479	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
 480		if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT ||
 481		    cmd->se_sess->sess_prot_type == TARGET_DIF_TYPE1_PROT)
 482			buf[4] = 0x5;
 483		else if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE3_PROT ||
 484			 cmd->se_sess->sess_prot_type == TARGET_DIF_TYPE3_PROT)
 485			buf[4] = 0x4;
 486	}
 487
 488	/* logical unit supports type 1 and type 3 protection */
 489	if ((dev->transport->get_device_type(dev) == TYPE_DISK) &&
 490	    (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) &&
 491	    (dev->dev_attrib.pi_prot_type || cmd->se_sess->sess_prot_type)) {
 492		buf[4] |= (0x3 << 3);
 493	}
 494
 495	/* Set HEADSUP, ORDSUP, SIMPSUP */
 496	buf[5] = 0x07;
 497
 498	/* If WriteCache emulation is enabled, set V_SUP */
 499	if (target_check_wce(dev))
 500		buf[6] = 0x01;
 501	/* If an LBA map is present set R_SUP */
 502	spin_lock(&cmd->se_dev->t10_alua.lba_map_lock);
 503	if (!list_empty(&dev->t10_alua.lba_map_list))
 504		buf[8] = 0x10;
 505	spin_unlock(&cmd->se_dev->t10_alua.lba_map_lock);
 506	return 0;
 507}
 508
 509/* Block Limits VPD page */
 510static sense_reason_t
 511spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf)
 512{
 513	struct se_device *dev = cmd->se_dev;
 514	u32 mtl = 0;
 515	int have_tp = 0, opt, min;
 516
 517	/*
 518	 * Following spc3r22 section 6.5.3 Block Limits VPD page, when
 519	 * emulate_tpu=1 or emulate_tpws=1 we will be expect a
 520	 * different page length for Thin Provisioning.
 521	 */
 522	if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws)
 523		have_tp = 1;
 524
 525	buf[0] = dev->transport->get_device_type(dev);
 526	buf[3] = have_tp ? 0x3c : 0x10;
 527
 528	/* Set WSNZ to 1 */
 529	buf[4] = 0x01;
 530	/*
 531	 * Set MAXIMUM COMPARE AND WRITE LENGTH
 532	 */
 533	if (dev->dev_attrib.emulate_caw)
 534		buf[5] = 0x01;
 535
 536	/*
 537	 * Set OPTIMAL TRANSFER LENGTH GRANULARITY
 538	 */
 539	if (dev->transport->get_io_min && (min = dev->transport->get_io_min(dev)))
 540		put_unaligned_be16(min / dev->dev_attrib.block_size, &buf[6]);
 541	else
 542		put_unaligned_be16(1, &buf[6]);
 543
 544	/*
 545	 * Set MAXIMUM TRANSFER LENGTH
 546	 *
 547	 * XXX: Currently assumes single PAGE_SIZE per scatterlist for fabrics
 548	 * enforcing maximum HW scatter-gather-list entry limit
 549	 */
 550	if (cmd->se_tfo->max_data_sg_nents) {
 551		mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE) /
 552		       dev->dev_attrib.block_size;
 553	}
 554	put_unaligned_be32(min_not_zero(mtl, dev->dev_attrib.hw_max_sectors), &buf[8]);
 555
 556	/*
 557	 * Set OPTIMAL TRANSFER LENGTH
 558	 */
 559	if (dev->transport->get_io_opt && (opt = dev->transport->get_io_opt(dev)))
 560		put_unaligned_be32(opt / dev->dev_attrib.block_size, &buf[12]);
 561	else
 562		put_unaligned_be32(dev->dev_attrib.optimal_sectors, &buf[12]);
 563
 564	/*
 565	 * Exit now if we don't support TP.
 566	 */
 567	if (!have_tp)
 568		goto max_write_same;
 569
 570	/*
 571	 * Set MAXIMUM UNMAP LBA COUNT
 572	 */
 573	put_unaligned_be32(dev->dev_attrib.max_unmap_lba_count, &buf[20]);
 574
 575	/*
 576	 * Set MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT
 577	 */
 578	put_unaligned_be32(dev->dev_attrib.max_unmap_block_desc_count,
 579			   &buf[24]);
 580
 581	/*
 582	 * Set OPTIMAL UNMAP GRANULARITY
 583	 */
 584	put_unaligned_be32(dev->dev_attrib.unmap_granularity, &buf[28]);
 585
 586	/*
 587	 * UNMAP GRANULARITY ALIGNMENT
 588	 */
 589	put_unaligned_be32(dev->dev_attrib.unmap_granularity_alignment,
 590			   &buf[32]);
 591	if (dev->dev_attrib.unmap_granularity_alignment != 0)
 592		buf[32] |= 0x80; /* Set the UGAVALID bit */
 593
 594	/*
 595	 * MAXIMUM WRITE SAME LENGTH
 596	 */
 597max_write_same:
 598	put_unaligned_be64(dev->dev_attrib.max_write_same_len, &buf[36]);
 599
 600	return 0;
 601}
 602
 603/* Block Device Characteristics VPD page */
 604static sense_reason_t
 605spc_emulate_evpd_b1(struct se_cmd *cmd, unsigned char *buf)
 606{
 607	struct se_device *dev = cmd->se_dev;
 608
 609	buf[0] = dev->transport->get_device_type(dev);
 610	buf[3] = 0x3c;
 611	buf[5] = dev->dev_attrib.is_nonrot ? 1 : 0;
 612
 613	return 0;
 614}
 615
 616/* Thin Provisioning VPD */
 617static sense_reason_t
 618spc_emulate_evpd_b2(struct se_cmd *cmd, unsigned char *buf)
 619{
 620	struct se_device *dev = cmd->se_dev;
 621
 622	/*
 623	 * From spc3r22 section 6.5.4 Thin Provisioning VPD page:
 624	 *
 625	 * The PAGE LENGTH field is defined in SPC-4. If the DP bit is set to
 626	 * zero, then the page length shall be set to 0004h.  If the DP bit
 627	 * is set to one, then the page length shall be set to the value
 628	 * defined in table 162.
 629	 */
 630	buf[0] = dev->transport->get_device_type(dev);
 631
 632	/*
 633	 * Set Hardcoded length mentioned above for DP=0
 634	 */
 635	put_unaligned_be16(0x0004, &buf[2]);
 636
 637	/*
 638	 * The THRESHOLD EXPONENT field indicates the threshold set size in
 639	 * LBAs as a power of 2 (i.e., the threshold set size is equal to
 640	 * 2(threshold exponent)).
 641	 *
 642	 * Note that this is currently set to 0x00 as mkp says it will be
 643	 * changing again.  We can enable this once it has settled in T10
 644	 * and is actually used by Linux/SCSI ML code.
 645	 */
 646	buf[4] = 0x00;
 647
 648	/*
 649	 * A TPU bit set to one indicates that the device server supports
 650	 * the UNMAP command (see 5.25). A TPU bit set to zero indicates
 651	 * that the device server does not support the UNMAP command.
 652	 */
 653	if (dev->dev_attrib.emulate_tpu != 0)
 654		buf[5] = 0x80;
 655
 656	/*
 657	 * A TPWS bit set to one indicates that the device server supports
 658	 * the use of the WRITE SAME (16) command (see 5.42) to unmap LBAs.
 659	 * A TPWS bit set to zero indicates that the device server does not
 660	 * support the use of the WRITE SAME (16) command to unmap LBAs.
 661	 */
 662	if (dev->dev_attrib.emulate_tpws != 0)
 663		buf[5] |= 0x40 | 0x20;
 664
 665	/*
 666	 * The unmap_zeroes_data set means that the underlying device supports
 667	 * REQ_OP_DISCARD and has the discard_zeroes_data bit set. This
 668	 * satisfies the SBC requirements for LBPRZ, meaning that a subsequent
 669	 * read will return zeroes after an UNMAP or WRITE SAME (16) to an LBA
 670	 * See sbc4r36 6.6.4.
 671	 */
 672	if (((dev->dev_attrib.emulate_tpu != 0) ||
 673	     (dev->dev_attrib.emulate_tpws != 0)) &&
 674	     (dev->dev_attrib.unmap_zeroes_data != 0))
 675		buf[5] |= 0x04;
 676
 677	return 0;
 678}
 679
 680/* Referrals VPD page */
 681static sense_reason_t
 682spc_emulate_evpd_b3(struct se_cmd *cmd, unsigned char *buf)
 683{
 684	struct se_device *dev = cmd->se_dev;
 685
 686	buf[0] = dev->transport->get_device_type(dev);
 687	buf[3] = 0x0c;
 688	put_unaligned_be32(dev->t10_alua.lba_map_segment_size, &buf[8]);
 689	put_unaligned_be32(dev->t10_alua.lba_map_segment_multiplier, &buf[12]);
 690
 691	return 0;
 692}
 693
 694static sense_reason_t
 695spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf);
 696
 697static struct {
 698	uint8_t		page;
 699	sense_reason_t	(*emulate)(struct se_cmd *, unsigned char *);
 700} evpd_handlers[] = {
 701	{ .page = 0x00, .emulate = spc_emulate_evpd_00 },
 702	{ .page = 0x80, .emulate = spc_emulate_evpd_80 },
 703	{ .page = 0x83, .emulate = spc_emulate_evpd_83 },
 704	{ .page = 0x86, .emulate = spc_emulate_evpd_86 },
 705	{ .page = 0xb0, .emulate = spc_emulate_evpd_b0 },
 706	{ .page = 0xb1, .emulate = spc_emulate_evpd_b1 },
 707	{ .page = 0xb2, .emulate = spc_emulate_evpd_b2 },
 708	{ .page = 0xb3, .emulate = spc_emulate_evpd_b3 },
 709};
 710
 711/* supported vital product data pages */
 712static sense_reason_t
 713spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf)
 714{
 715	int p;
 716
 717	/*
 718	 * Only report the INQUIRY EVPD=1 pages after a valid NAA
 719	 * Registered Extended LUN WWN has been set via ConfigFS
 720	 * during device creation/restart.
 721	 */
 722	if (cmd->se_dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL) {
 723		buf[3] = ARRAY_SIZE(evpd_handlers);
 724		for (p = 0; p < ARRAY_SIZE(evpd_handlers); ++p)
 725			buf[p + 4] = evpd_handlers[p].page;
 726	}
 727
 728	return 0;
 729}
 730
 731static sense_reason_t
 732spc_emulate_inquiry(struct se_cmd *cmd)
 733{
 734	struct se_device *dev = cmd->se_dev;
 735	unsigned char *rbuf;
 736	unsigned char *cdb = cmd->t_task_cdb;
 737	unsigned char *buf;
 738	sense_reason_t ret;
 739	int p;
 740	int len = 0;
 741
 742	buf = kzalloc(SE_INQUIRY_BUF, GFP_KERNEL);
 743	if (!buf) {
 744		pr_err("Unable to allocate response buffer for INQUIRY\n");
 745		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 746	}
 747
 748	buf[0] = dev->transport->get_device_type(dev);
 749
 750	if (!(cdb[1] & 0x1)) {
 751		if (cdb[2]) {
 752			pr_err("INQUIRY with EVPD==0 but PAGE CODE=%02x\n",
 753			       cdb[2]);
 754			ret = TCM_INVALID_CDB_FIELD;
 755			goto out;
 756		}
 757
 758		ret = spc_emulate_inquiry_std(cmd, buf);
 759		len = buf[4] + 5;
 760		goto out;
 761	}
 762
 763	for (p = 0; p < ARRAY_SIZE(evpd_handlers); ++p) {
 764		if (cdb[2] == evpd_handlers[p].page) {
 765			buf[1] = cdb[2];
 766			ret = evpd_handlers[p].emulate(cmd, buf);
 767			len = get_unaligned_be16(&buf[2]) + 4;
 768			goto out;
 769		}
 770	}
 771
 772	pr_err("Unknown VPD Code: 0x%02x\n", cdb[2]);
 773	ret = TCM_INVALID_CDB_FIELD;
 774
 775out:
 776	rbuf = transport_kmap_data_sg(cmd);
 777	if (rbuf) {
 778		memcpy(rbuf, buf, min_t(u32, SE_INQUIRY_BUF, cmd->data_length));
 779		transport_kunmap_data_sg(cmd);
 780	}
 781	kfree(buf);
 782
 783	if (!ret)
 784		target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, len);
 785	return ret;
 786}
 787
 788static int spc_modesense_rwrecovery(struct se_cmd *cmd, u8 pc, u8 *p)
 789{
 790	p[0] = 0x01;
 791	p[1] = 0x0a;
 792
 793	/* No changeable values for now */
 794	if (pc == 1)
 795		goto out;
 796
 797out:
 798	return 12;
 799}
 800
 801static int spc_modesense_control(struct se_cmd *cmd, u8 pc, u8 *p)
 802{
 803	struct se_device *dev = cmd->se_dev;
 804	struct se_session *sess = cmd->se_sess;
 805
 806	p[0] = 0x0a;
 807	p[1] = 0x0a;
 808
 809	/* No changeable values for now */
 810	if (pc == 1)
 811		goto out;
 812
 813	/* GLTSD: No implicit save of log parameters */
 814	p[2] = (1 << 1);
 815	if (target_sense_desc_format(dev))
 816		/* D_SENSE: Descriptor format sense data for 64bit sectors */
 817		p[2] |= (1 << 2);
 818
 819	/*
 820	 * From spc4r23, 7.4.7 Control mode page
 821	 *
 822	 * The QUEUE ALGORITHM MODIFIER field (see table 368) specifies
 823	 * restrictions on the algorithm used for reordering commands
 824	 * having the SIMPLE task attribute (see SAM-4).
 825	 *
 826	 *                    Table 368 -- QUEUE ALGORITHM MODIFIER field
 827	 *                         Code      Description
 828	 *                          0h       Restricted reordering
 829	 *                          1h       Unrestricted reordering allowed
 830	 *                          2h to 7h    Reserved
 831	 *                          8h to Fh    Vendor specific
 832	 *
 833	 * A value of zero in the QUEUE ALGORITHM MODIFIER field specifies that
 834	 * the device server shall order the processing sequence of commands
 835	 * having the SIMPLE task attribute such that data integrity is maintained
 836	 * for that I_T nexus (i.e., if the transmission of new SCSI transport protocol
 837	 * requests is halted at any time, the final value of all data observable
 838	 * on the medium shall be the same as if all the commands had been processed
 839	 * with the ORDERED task attribute).
 840	 *
 841	 * A value of one in the QUEUE ALGORITHM MODIFIER field specifies that the
 842	 * device server may reorder the processing sequence of commands having the
 843	 * SIMPLE task attribute in any manner. Any data integrity exposures related to
 844	 * command sequence order shall be explicitly handled by the application client
 845	 * through the selection of appropriate ommands and task attributes.
 846	 */
 847	p[3] = (dev->dev_attrib.emulate_rest_reord == 1) ? 0x00 : 0x10;
 848	/*
 849	 * From spc4r17, section 7.4.6 Control mode Page
 850	 *
 851	 * Unit Attention interlocks control (UN_INTLCK_CTRL) to code 00b
 852	 *
 853	 * 00b: The logical unit shall clear any unit attention condition
 854	 * reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
 855	 * status and shall not establish a unit attention condition when a com-
 856	 * mand is completed with BUSY, TASK SET FULL, or RESERVATION CONFLICT
 857	 * status.
 858	 *
 859	 * 10b: The logical unit shall not clear any unit attention condition
 860	 * reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
 861	 * status and shall not establish a unit attention condition when
 862	 * a command is completed with BUSY, TASK SET FULL, or RESERVATION
 863	 * CONFLICT status.
 864	 *
 865	 * 11b a The logical unit shall not clear any unit attention condition
 866	 * reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
 867	 * status and shall establish a unit attention condition for the
 868	 * initiator port associated with the I_T nexus on which the BUSY,
 869	 * TASK SET FULL, or RESERVATION CONFLICT status is being returned.
 870	 * Depending on the status, the additional sense code shall be set to
 871	 * PREVIOUS BUSY STATUS, PREVIOUS TASK SET FULL STATUS, or PREVIOUS
 872	 * RESERVATION CONFLICT STATUS. Until it is cleared by a REQUEST SENSE
 873	 * command, a unit attention condition shall be established only once
 874	 * for a BUSY, TASK SET FULL, or RESERVATION CONFLICT status regardless
 875	 * to the number of commands completed with one of those status codes.
 876	 */
 877	switch (dev->dev_attrib.emulate_ua_intlck_ctrl) {
 878	case TARGET_UA_INTLCK_CTRL_ESTABLISH_UA:
 879		p[4] = 0x30;
 880		break;
 881	case TARGET_UA_INTLCK_CTRL_NO_CLEAR:
 882		p[4] = 0x20;
 883		break;
 884	default:	/* TARGET_UA_INTLCK_CTRL_CLEAR */
 885		p[4] = 0x00;
 886		break;
 887	}
 888	/*
 889	 * From spc4r17, section 7.4.6 Control mode Page
 890	 *
 891	 * Task Aborted Status (TAS) bit set to zero.
 892	 *
 893	 * A task aborted status (TAS) bit set to zero specifies that aborted
 894	 * tasks shall be terminated by the device server without any response
 895	 * to the application client. A TAS bit set to one specifies that tasks
 896	 * aborted by the actions of an I_T nexus other than the I_T nexus on
 897	 * which the command was received shall be completed with TASK ABORTED
 898	 * status (see SAM-4).
 899	 */
 900	p[5] = (dev->dev_attrib.emulate_tas) ? 0x40 : 0x00;
 901	/*
 902	 * From spc4r30, section 7.5.7 Control mode page
 903	 *
 904	 * Application Tag Owner (ATO) bit set to one.
 905	 *
 906	 * If the ATO bit is set to one the device server shall not modify the
 907	 * LOGICAL BLOCK APPLICATION TAG field and, depending on the protection
 908	 * type, shall not modify the contents of the LOGICAL BLOCK REFERENCE
 909	 * TAG field.
 910	 */
 911	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
 912		if (dev->dev_attrib.pi_prot_type || sess->sess_prot_type)
 913			p[5] |= 0x80;
 914	}
 915
 916	p[8] = 0xff;
 917	p[9] = 0xff;
 918	p[11] = 30;
 919
 920out:
 921	return 12;
 922}
 923
 924static int spc_modesense_caching(struct se_cmd *cmd, u8 pc, u8 *p)
 925{
 926	struct se_device *dev = cmd->se_dev;
 927
 928	p[0] = 0x08;
 929	p[1] = 0x12;
 930
 931	/* No changeable values for now */
 932	if (pc == 1)
 933		goto out;
 934
 935	if (target_check_wce(dev))
 936		p[2] = 0x04; /* Write Cache Enable */
 937	p[12] = 0x20; /* Disabled Read Ahead */
 938
 939out:
 940	return 20;
 941}
 942
 943static int spc_modesense_informational_exceptions(struct se_cmd *cmd, u8 pc, unsigned char *p)
 944{
 945	p[0] = 0x1c;
 946	p[1] = 0x0a;
 947
 948	/* No changeable values for now */
 949	if (pc == 1)
 950		goto out;
 951
 952out:
 953	return 12;
 954}
 955
 956static struct {
 957	uint8_t		page;
 958	uint8_t		subpage;
 959	int		(*emulate)(struct se_cmd *, u8, unsigned char *);
 960} modesense_handlers[] = {
 961	{ .page = 0x01, .subpage = 0x00, .emulate = spc_modesense_rwrecovery },
 962	{ .page = 0x08, .subpage = 0x00, .emulate = spc_modesense_caching },
 963	{ .page = 0x0a, .subpage = 0x00, .emulate = spc_modesense_control },
 964	{ .page = 0x1c, .subpage = 0x00, .emulate = spc_modesense_informational_exceptions },
 965};
 966
 967static void spc_modesense_write_protect(unsigned char *buf, int type)
 968{
 969	/*
 970	 * I believe that the WP bit (bit 7) in the mode header is the same for
 971	 * all device types..
 972	 */
 973	switch (type) {
 974	case TYPE_DISK:
 975	case TYPE_TAPE:
 976	default:
 977		buf[0] |= 0x80; /* WP bit */
 978		break;
 979	}
 980}
 981
 982static void spc_modesense_dpofua(unsigned char *buf, int type)
 983{
 984	switch (type) {
 985	case TYPE_DISK:
 986		buf[0] |= 0x10; /* DPOFUA bit */
 987		break;
 988	default:
 989		break;
 990	}
 991}
 992
 993static int spc_modesense_blockdesc(unsigned char *buf, u64 blocks, u32 block_size)
 994{
 995	*buf++ = 8;
 996	put_unaligned_be32(min(blocks, 0xffffffffull), buf);
 997	buf += 4;
 998	put_unaligned_be32(block_size, buf);
 999	return 9;
1000}
1001
1002static int spc_modesense_long_blockdesc(unsigned char *buf, u64 blocks, u32 block_size)
1003{
1004	if (blocks <= 0xffffffff)
1005		return spc_modesense_blockdesc(buf + 3, blocks, block_size) + 3;
1006
1007	*buf++ = 1;		/* LONGLBA */
1008	buf += 2;
1009	*buf++ = 16;
1010	put_unaligned_be64(blocks, buf);
1011	buf += 12;
1012	put_unaligned_be32(block_size, buf);
1013
1014	return 17;
1015}
1016
1017static sense_reason_t spc_emulate_modesense(struct se_cmd *cmd)
1018{
1019	struct se_device *dev = cmd->se_dev;
1020	char *cdb = cmd->t_task_cdb;
1021	unsigned char buf[SE_MODE_PAGE_BUF], *rbuf;
1022	int type = dev->transport->get_device_type(dev);
1023	int ten = (cmd->t_task_cdb[0] == MODE_SENSE_10);
1024	bool dbd = !!(cdb[1] & 0x08);
1025	bool llba = ten ? !!(cdb[1] & 0x10) : false;
1026	u8 pc = cdb[2] >> 6;
1027	u8 page = cdb[2] & 0x3f;
1028	u8 subpage = cdb[3];
1029	int length = 0;
1030	int ret;
1031	int i;
1032
1033	memset(buf, 0, SE_MODE_PAGE_BUF);
1034
1035	/*
1036	 * Skip over MODE DATA LENGTH + MEDIUM TYPE fields to byte 3 for
1037	 * MODE_SENSE_10 and byte 2 for MODE_SENSE (6).
1038	 */
1039	length = ten ? 3 : 2;
1040
1041	/* DEVICE-SPECIFIC PARAMETER */
1042	if (cmd->se_lun->lun_access_ro || target_lun_is_rdonly(cmd))
1043		spc_modesense_write_protect(&buf[length], type);
1044
1045	/*
1046	 * SBC only allows us to enable FUA and DPO together.  Fortunately
1047	 * DPO is explicitly specified as a hint, so a noop is a perfectly
1048	 * valid implementation.
1049	 */
1050	if (target_check_fua(dev))
1051		spc_modesense_dpofua(&buf[length], type);
1052
1053	++length;
1054
1055	/* BLOCK DESCRIPTOR */
1056
1057	/*
1058	 * For now we only include a block descriptor for disk (SBC)
1059	 * devices; other command sets use a slightly different format.
1060	 */
1061	if (!dbd && type == TYPE_DISK) {
1062		u64 blocks = dev->transport->get_blocks(dev);
1063		u32 block_size = dev->dev_attrib.block_size;
1064
1065		if (ten) {
1066			if (llba) {
1067				length += spc_modesense_long_blockdesc(&buf[length],
1068								       blocks, block_size);
1069			} else {
1070				length += 3;
1071				length += spc_modesense_blockdesc(&buf[length],
1072								  blocks, block_size);
1073			}
1074		} else {
1075			length += spc_modesense_blockdesc(&buf[length], blocks,
1076							  block_size);
1077		}
1078	} else {
1079		if (ten)
1080			length += 4;
1081		else
1082			length += 1;
1083	}
1084
1085	if (page == 0x3f) {
1086		if (subpage != 0x00 && subpage != 0xff) {
1087			pr_warn("MODE_SENSE: Invalid subpage code: 0x%02x\n", subpage);
1088			return TCM_INVALID_CDB_FIELD;
1089		}
1090
1091		for (i = 0; i < ARRAY_SIZE(modesense_handlers); ++i) {
1092			/*
1093			 * Tricky way to say all subpage 00h for
1094			 * subpage==0, all subpages for subpage==0xff
1095			 * (and we just checked above that those are
1096			 * the only two possibilities).
1097			 */
1098			if ((modesense_handlers[i].subpage & ~subpage) == 0) {
1099				ret = modesense_handlers[i].emulate(cmd, pc, &buf[length]);
1100				if (!ten && length + ret >= 255)
1101					break;
1102				length += ret;
1103			}
1104		}
1105
1106		goto set_length;
1107	}
1108
1109	for (i = 0; i < ARRAY_SIZE(modesense_handlers); ++i)
1110		if (modesense_handlers[i].page == page &&
1111		    modesense_handlers[i].subpage == subpage) {
1112			length += modesense_handlers[i].emulate(cmd, pc, &buf[length]);
1113			goto set_length;
1114		}
1115
1116	/*
1117	 * We don't intend to implement:
1118	 *  - obsolete page 03h "format parameters" (checked by Solaris)
1119	 */
1120	if (page != 0x03)
1121		pr_err("MODE SENSE: unimplemented page/subpage: 0x%02x/0x%02x\n",
1122		       page, subpage);
1123
1124	return TCM_UNKNOWN_MODE_PAGE;
1125
1126set_length:
1127	if (ten)
1128		put_unaligned_be16(length - 2, buf);
1129	else
1130		buf[0] = length - 1;
1131
1132	rbuf = transport_kmap_data_sg(cmd);
1133	if (rbuf) {
1134		memcpy(rbuf, buf, min_t(u32, SE_MODE_PAGE_BUF, cmd->data_length));
1135		transport_kunmap_data_sg(cmd);
1136	}
1137
1138	target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, length);
1139	return 0;
1140}
1141
1142static sense_reason_t spc_emulate_modeselect(struct se_cmd *cmd)
1143{
1144	char *cdb = cmd->t_task_cdb;
1145	bool ten = cdb[0] == MODE_SELECT_10;
1146	int off = ten ? 8 : 4;
1147	bool pf = !!(cdb[1] & 0x10);
1148	u8 page, subpage;
1149	unsigned char *buf;
1150	unsigned char tbuf[SE_MODE_PAGE_BUF];
1151	int length;
1152	sense_reason_t ret = 0;
1153	int i;
1154
1155	if (!cmd->data_length) {
1156		target_complete_cmd(cmd, SAM_STAT_GOOD);
1157		return 0;
1158	}
1159
1160	if (cmd->data_length < off + 2)
1161		return TCM_PARAMETER_LIST_LENGTH_ERROR;
1162
1163	buf = transport_kmap_data_sg(cmd);
1164	if (!buf)
1165		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1166
1167	if (!pf) {
1168		ret = TCM_INVALID_CDB_FIELD;
1169		goto out;
1170	}
1171
1172	page = buf[off] & 0x3f;
1173	subpage = buf[off] & 0x40 ? buf[off + 1] : 0;
1174
1175	for (i = 0; i < ARRAY_SIZE(modesense_handlers); ++i)
1176		if (modesense_handlers[i].page == page &&
1177		    modesense_handlers[i].subpage == subpage) {
1178			memset(tbuf, 0, SE_MODE_PAGE_BUF);
1179			length = modesense_handlers[i].emulate(cmd, 0, tbuf);
1180			goto check_contents;
1181		}
1182
1183	ret = TCM_UNKNOWN_MODE_PAGE;
1184	goto out;
1185
1186check_contents:
1187	if (cmd->data_length < off + length) {
1188		ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
1189		goto out;
1190	}
1191
1192	if (memcmp(buf + off, tbuf, length))
1193		ret = TCM_INVALID_PARAMETER_LIST;
1194
1195out:
1196	transport_kunmap_data_sg(cmd);
1197
1198	if (!ret)
1199		target_complete_cmd(cmd, SAM_STAT_GOOD);
1200	return ret;
1201}
1202
1203static sense_reason_t spc_emulate_request_sense(struct se_cmd *cmd)
1204{
1205	unsigned char *cdb = cmd->t_task_cdb;
1206	unsigned char *rbuf;
1207	u8 ua_asc = 0, ua_ascq = 0;
1208	unsigned char buf[SE_SENSE_BUF];
1209	bool desc_format = target_sense_desc_format(cmd->se_dev);
1210
1211	memset(buf, 0, SE_SENSE_BUF);
1212
1213	if (cdb[1] & 0x01) {
1214		pr_err("REQUEST_SENSE description emulation not"
1215			" supported\n");
1216		return TCM_INVALID_CDB_FIELD;
1217	}
1218
1219	rbuf = transport_kmap_data_sg(cmd);
1220	if (!rbuf)
1221		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1222
1223	if (!core_scsi3_ua_clear_for_request_sense(cmd, &ua_asc, &ua_ascq))
1224		scsi_build_sense_buffer(desc_format, buf, UNIT_ATTENTION,
1225					ua_asc, ua_ascq);
1226	else
1227		scsi_build_sense_buffer(desc_format, buf, NO_SENSE, 0x0, 0x0);
1228
1229	memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
1230	transport_kunmap_data_sg(cmd);
1231
1232	target_complete_cmd(cmd, SAM_STAT_GOOD);
1233	return 0;
1234}
1235
1236sense_reason_t spc_emulate_report_luns(struct se_cmd *cmd)
1237{
1238	struct se_dev_entry *deve;
1239	struct se_session *sess = cmd->se_sess;
1240	struct se_node_acl *nacl;
1241	struct scsi_lun slun;
1242	unsigned char *buf;
1243	u32 lun_count = 0, offset = 8;
1244	__be32 len;
1245
1246	buf = transport_kmap_data_sg(cmd);
1247	if (cmd->data_length && !buf)
1248		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1249
1250	/*
1251	 * If no struct se_session pointer is present, this struct se_cmd is
1252	 * coming via a target_core_mod PASSTHROUGH op, and not through
1253	 * a $FABRIC_MOD.  In that case, report LUN=0 only.
1254	 */
1255	if (!sess)
1256		goto done;
1257
1258	nacl = sess->se_node_acl;
1259
1260	rcu_read_lock();
1261	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
1262		/*
1263		 * We determine the correct LUN LIST LENGTH even once we
1264		 * have reached the initial allocation length.
1265		 * See SPC2-R20 7.19.
1266		 */
1267		lun_count++;
1268		if (offset >= cmd->data_length)
1269			continue;
1270
1271		int_to_scsilun(deve->mapped_lun, &slun);
1272		memcpy(buf + offset, &slun,
1273		       min(8u, cmd->data_length - offset));
1274		offset += 8;
1275	}
1276	rcu_read_unlock();
1277
1278	/*
1279	 * See SPC3 r07, page 159.
1280	 */
1281done:
1282	/*
1283	 * If no LUNs are accessible, report virtual LUN 0.
1284	 */
1285	if (lun_count == 0) {
1286		int_to_scsilun(0, &slun);
1287		if (cmd->data_length > 8)
1288			memcpy(buf + offset, &slun,
1289			       min(8u, cmd->data_length - offset));
1290		lun_count = 1;
1291	}
1292
1293	if (buf) {
1294		len = cpu_to_be32(lun_count * 8);
1295		memcpy(buf, &len, min_t(int, sizeof len, cmd->data_length));
1296		transport_kunmap_data_sg(cmd);
1297	}
1298
1299	target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, 8 + lun_count * 8);
1300	return 0;
1301}
1302EXPORT_SYMBOL(spc_emulate_report_luns);
1303
1304static sense_reason_t
1305spc_emulate_testunitready(struct se_cmd *cmd)
1306{
1307	target_complete_cmd(cmd, SAM_STAT_GOOD);
1308	return 0;
1309}
1310
1311sense_reason_t
1312spc_parse_cdb(struct se_cmd *cmd, unsigned int *size)
1313{
1314	struct se_device *dev = cmd->se_dev;
1315	unsigned char *cdb = cmd->t_task_cdb;
1316
1317	if (!dev->dev_attrib.emulate_pr &&
1318	    ((cdb[0] == PERSISTENT_RESERVE_IN) ||
1319	     (cdb[0] == PERSISTENT_RESERVE_OUT) ||
1320	     (cdb[0] == RELEASE || cdb[0] == RELEASE_10) ||
1321	     (cdb[0] == RESERVE || cdb[0] == RESERVE_10))) {
1322		return TCM_UNSUPPORTED_SCSI_OPCODE;
1323	}
1324
1325	switch (cdb[0]) {
1326	case MODE_SELECT:
1327		*size = cdb[4];
1328		cmd->execute_cmd = spc_emulate_modeselect;
1329		break;
1330	case MODE_SELECT_10:
1331		*size = get_unaligned_be16(&cdb[7]);
1332		cmd->execute_cmd = spc_emulate_modeselect;
1333		break;
1334	case MODE_SENSE:
1335		*size = cdb[4];
1336		cmd->execute_cmd = spc_emulate_modesense;
1337		break;
1338	case MODE_SENSE_10:
1339		*size = get_unaligned_be16(&cdb[7]);
1340		cmd->execute_cmd = spc_emulate_modesense;
1341		break;
1342	case LOG_SELECT:
1343	case LOG_SENSE:
1344		*size = get_unaligned_be16(&cdb[7]);
1345		break;
1346	case PERSISTENT_RESERVE_IN:
1347		*size = get_unaligned_be16(&cdb[7]);
1348		cmd->execute_cmd = target_scsi3_emulate_pr_in;
1349		break;
1350	case PERSISTENT_RESERVE_OUT:
1351		*size = get_unaligned_be32(&cdb[5]);
1352		cmd->execute_cmd = target_scsi3_emulate_pr_out;
1353		break;
1354	case RELEASE:
1355	case RELEASE_10:
1356		if (cdb[0] == RELEASE_10)
1357			*size = get_unaligned_be16(&cdb[7]);
1358		else
1359			*size = cmd->data_length;
1360
1361		cmd->execute_cmd = target_scsi2_reservation_release;
1362		break;
1363	case RESERVE:
1364	case RESERVE_10:
1365		/*
1366		 * The SPC-2 RESERVE does not contain a size in the SCSI CDB.
1367		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
1368		 */
1369		if (cdb[0] == RESERVE_10)
1370			*size = get_unaligned_be16(&cdb[7]);
1371		else
1372			*size = cmd->data_length;
1373
1374		cmd->execute_cmd = target_scsi2_reservation_reserve;
1375		break;
1376	case REQUEST_SENSE:
1377		*size = cdb[4];
1378		cmd->execute_cmd = spc_emulate_request_sense;
1379		break;
1380	case INQUIRY:
1381		*size = get_unaligned_be16(&cdb[3]);
1382
1383		/*
1384		 * Do implicit HEAD_OF_QUEUE processing for INQUIRY.
1385		 * See spc4r17 section 5.3
1386		 */
1387		cmd->sam_task_attr = TCM_HEAD_TAG;
1388		cmd->execute_cmd = spc_emulate_inquiry;
1389		break;
1390	case SECURITY_PROTOCOL_IN:
1391	case SECURITY_PROTOCOL_OUT:
1392		*size = get_unaligned_be32(&cdb[6]);
1393		break;
1394	case EXTENDED_COPY:
1395		*size = get_unaligned_be32(&cdb[10]);
1396		cmd->execute_cmd = target_do_xcopy;
1397		break;
1398	case RECEIVE_COPY_RESULTS:
1399		*size = get_unaligned_be32(&cdb[10]);
1400		cmd->execute_cmd = target_do_receive_copy_results;
1401		break;
1402	case READ_ATTRIBUTE:
1403	case WRITE_ATTRIBUTE:
1404		*size = get_unaligned_be32(&cdb[10]);
1405		break;
1406	case RECEIVE_DIAGNOSTIC:
1407	case SEND_DIAGNOSTIC:
1408		*size = get_unaligned_be16(&cdb[3]);
1409		break;
1410	case WRITE_BUFFER:
1411		*size = get_unaligned_be24(&cdb[6]);
1412		break;
1413	case REPORT_LUNS:
1414		cmd->execute_cmd = spc_emulate_report_luns;
1415		*size = get_unaligned_be32(&cdb[6]);
1416		/*
1417		 * Do implicit HEAD_OF_QUEUE processing for REPORT_LUNS
1418		 * See spc4r17 section 5.3
1419		 */
1420		cmd->sam_task_attr = TCM_HEAD_TAG;
1421		break;
1422	case TEST_UNIT_READY:
1423		cmd->execute_cmd = spc_emulate_testunitready;
1424		*size = 0;
1425		break;
1426	case MAINTENANCE_IN:
1427		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
1428			/*
1429			 * MAINTENANCE_IN from SCC-2
1430			 * Check for emulated MI_REPORT_TARGET_PGS
1431			 */
1432			if ((cdb[1] & 0x1f) == MI_REPORT_TARGET_PGS) {
1433				cmd->execute_cmd =
1434					target_emulate_report_target_port_groups;
1435			}
1436			*size = get_unaligned_be32(&cdb[6]);
1437		} else {
1438			/*
1439			 * GPCMD_SEND_KEY from multi media commands
1440			 */
1441			*size = get_unaligned_be16(&cdb[8]);
1442		}
1443		break;
1444	case MAINTENANCE_OUT:
1445		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
1446			/*
1447			 * MAINTENANCE_OUT from SCC-2
1448			 * Check for emulated MO_SET_TARGET_PGS.
1449			 */
1450			if (cdb[1] == MO_SET_TARGET_PGS) {
1451				cmd->execute_cmd =
1452					target_emulate_set_target_port_groups;
1453			}
1454			*size = get_unaligned_be32(&cdb[6]);
1455		} else {
1456			/*
1457			 * GPCMD_SEND_KEY from multi media commands
1458			 */
1459			*size = get_unaligned_be16(&cdb[8]);
1460		}
1461		break;
1462	default:
1463		return TCM_UNSUPPORTED_SCSI_OPCODE;
1464	}
1465
1466	return 0;
1467}
1468EXPORT_SYMBOL(spc_parse_cdb);