1 /*
2  * SCSI Primary Commands (SPC) 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 <asm/unaligned.h>
26 
27 #include <scsi/scsi_proto.h>
28 #include <scsi/scsi_common.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_alua.h"
37 #include "target_core_pr.h"
38 #include "target_core_ua.h"
39 #include "target_core_xcopy.h"
40 
41 static void spc_fill_alua_data(struct se_lun *lun, unsigned char *buf)
42 {
43 	struct t10_alua_tg_pt_gp *tg_pt_gp;
44 
45 	/*
46 	 * Set SCCS for MAINTENANCE_IN + REPORT_TARGET_PORT_GROUPS.
47 	 */
48 	buf[5]	= 0x80;
49 
50 	/*
51 	 * Set TPGS field for explicit and/or implicit ALUA access type
52 	 * and opteration.
53 	 *
54 	 * See spc4r17 section 6.4.2 Table 135
55 	 */
56 	spin_lock(&lun->lun_tg_pt_gp_lock);
57 	tg_pt_gp = lun->lun_tg_pt_gp;
58 	if (tg_pt_gp)
59 		buf[5] |= tg_pt_gp->tg_pt_gp_alua_access_type;
60 	spin_unlock(&lun->lun_tg_pt_gp_lock);
61 }
62 
63 sense_reason_t
64 spc_emulate_inquiry_std(struct se_cmd *cmd, unsigned char *buf)
65 {
66 	struct se_lun *lun = cmd->se_lun;
67 	struct se_device *dev = cmd->se_dev;
68 	struct se_session *sess = cmd->se_sess;
69 
70 	/* Set RMB (removable media) for tape devices */
71 	if (dev->transport->get_device_type(dev) == TYPE_TAPE)
72 		buf[1] = 0x80;
73 
74 	buf[2] = 0x05; /* SPC-3 */
75 
76 	/*
77 	 * NORMACA and HISUP = 0, RESPONSE DATA FORMAT = 2
78 	 *
79 	 * SPC4 says:
80 	 *   A RESPONSE DATA FORMAT field set to 2h indicates that the
81 	 *   standard INQUIRY data is in the format defined in this
82 	 *   standard. Response data format values less than 2h are
83 	 *   obsolete. Response data format values greater than 2h are
84 	 *   reserved.
85 	 */
86 	buf[3] = 2;
87 
88 	/*
89 	 * Enable SCCS and TPGS fields for Emulated ALUA
90 	 */
91 	spc_fill_alua_data(lun, buf);
92 
93 	/*
94 	 * Set Third-Party Copy (3PC) bit to indicate support for EXTENDED_COPY
95 	 */
96 	if (dev->dev_attrib.emulate_3pc)
97 		buf[5] |= 0x8;
98 	/*
99 	 * Set Protection (PROTECT) bit when DIF has been enabled on the
100 	 * device, and the fabric supports VERIFY + PASS.  Also report
101 	 * PROTECT=1 if sess_prot_type has been configured to allow T10-PI
102 	 * to unprotected devices.
103 	 */
104 	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
105 		if (dev->dev_attrib.pi_prot_type || cmd->se_sess->sess_prot_type)
106 			buf[5] |= 0x1;
107 	}
108 
109 	buf[7] = 0x2; /* CmdQue=1 */
110 
111 	/*
112 	 * ASCII data fields described as being left-aligned shall have any
113 	 * unused bytes at the end of the field (i.e., highest offset) and the
114 	 * unused bytes shall be filled with ASCII space characters (20h).
115 	 */
116 	memset(&buf[8], 0x20,
117 	       INQUIRY_VENDOR_LEN + INQUIRY_MODEL_LEN + INQUIRY_REVISION_LEN);
118 	memcpy(&buf[8], dev->t10_wwn.vendor,
119 	       strnlen(dev->t10_wwn.vendor, INQUIRY_VENDOR_LEN));
120 	memcpy(&buf[16], dev->t10_wwn.model,
121 	       strnlen(dev->t10_wwn.model, INQUIRY_MODEL_LEN));
122 	memcpy(&buf[32], dev->t10_wwn.revision,
123 	       strnlen(dev->t10_wwn.revision, INQUIRY_REVISION_LEN));
124 	buf[4] = 31; /* Set additional length to 31 */
125 
126 	return 0;
127 }
128 EXPORT_SYMBOL(spc_emulate_inquiry_std);
129 
130 /* unit serial number */
131 static sense_reason_t
132 spc_emulate_evpd_80(struct se_cmd *cmd, unsigned char *buf)
133 {
134 	struct se_device *dev = cmd->se_dev;
135 	u16 len;
136 
137 	if (dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL) {
138 		len = sprintf(&buf[4], "%s", dev->t10_wwn.unit_serial);
139 		len++; /* Extra Byte for NULL Terminator */
140 		buf[3] = len;
141 	}
142 	return 0;
143 }
144 
145 void spc_parse_naa_6h_vendor_specific(struct se_device *dev,
146 				      unsigned char *buf)
147 {
148 	unsigned char *p = &dev->t10_wwn.unit_serial[0];
149 	int cnt;
150 	bool next = true;
151 
152 	/*
153 	 * Generate up to 36 bits of VENDOR SPECIFIC IDENTIFIER starting on
154 	 * byte 3 bit 3-0 for NAA IEEE Registered Extended DESIGNATOR field
155 	 * format, followed by 64 bits of VENDOR SPECIFIC IDENTIFIER EXTENSION
156 	 * to complete the payload.  These are based from VPD=0x80 PRODUCT SERIAL
157 	 * NUMBER set via vpd_unit_serial in target_core_configfs.c to ensure
158 	 * per device uniqeness.
159 	 */
160 	for (cnt = 0; *p && cnt < 13; p++) {
161 		int val = hex_to_bin(*p);
162 
163 		if (val < 0)
164 			continue;
165 
166 		if (next) {
167 			next = false;
168 			buf[cnt++] |= val;
169 		} else {
170 			next = true;
171 			buf[cnt] = val << 4;
172 		}
173 	}
174 }
175 
176 /*
177  * Device identification VPD, for a complete list of
178  * DESIGNATOR TYPEs see spc4r17 Table 459.
179  */
180 sense_reason_t
181 spc_emulate_evpd_83(struct se_cmd *cmd, unsigned char *buf)
182 {
183 	struct se_device *dev = cmd->se_dev;
184 	struct se_lun *lun = cmd->se_lun;
185 	struct se_portal_group *tpg = NULL;
186 	struct t10_alua_lu_gp_member *lu_gp_mem;
187 	struct t10_alua_tg_pt_gp *tg_pt_gp;
188 	unsigned char *prod = &dev->t10_wwn.model[0];
189 	u32 prod_len;
190 	u32 unit_serial_len, off = 0;
191 	u16 len = 0, id_len;
192 
193 	off = 4;
194 
195 	/*
196 	 * NAA IEEE Registered Extended Assigned designator format, see
197 	 * spc4r17 section 7.7.3.6.5
198 	 *
199 	 * We depend upon a target_core_mod/ConfigFS provided
200 	 * /sys/kernel/config/target/core/$HBA/$DEV/wwn/vpd_unit_serial
201 	 * value in order to return the NAA id.
202 	 */
203 	if (!(dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL))
204 		goto check_t10_vend_desc;
205 
206 	/* CODE SET == Binary */
207 	buf[off++] = 0x1;
208 
209 	/* Set ASSOCIATION == addressed logical unit: 0)b */
210 	buf[off] = 0x00;
211 
212 	/* Identifier/Designator type == NAA identifier */
213 	buf[off++] |= 0x3;
214 	off++;
215 
216 	/* Identifier/Designator length */
217 	buf[off++] = 0x10;
218 
219 	/*
220 	 * Start NAA IEEE Registered Extended Identifier/Designator
221 	 */
222 	buf[off++] = (0x6 << 4);
223 
224 	/*
225 	 * Use OpenFabrics IEEE Company ID: 00 14 05
226 	 */
227 	buf[off++] = 0x01;
228 	buf[off++] = 0x40;
229 	buf[off] = (0x5 << 4);
230 
231 	/*
232 	 * Return ConfigFS Unit Serial Number information for
233 	 * VENDOR_SPECIFIC_IDENTIFIER and
234 	 * VENDOR_SPECIFIC_IDENTIFIER_EXTENTION
235 	 */
236 	spc_parse_naa_6h_vendor_specific(dev, &buf[off]);
237 
238 	len = 20;
239 	off = (len + 4);
240 
241 check_t10_vend_desc:
242 	/*
243 	 * T10 Vendor Identifier Page, see spc4r17 section 7.7.3.4
244 	 */
245 	id_len = 8; /* For Vendor field */
246 	prod_len = 4; /* For VPD Header */
247 	prod_len += 8; /* For Vendor field */
248 	prod_len += strlen(prod);
249 	prod_len++; /* For : */
250 
251 	if (dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL) {
252 		unit_serial_len = strlen(&dev->t10_wwn.unit_serial[0]);
253 		unit_serial_len++; /* For NULL Terminator */
254 
255 		id_len += sprintf(&buf[off+12], "%s:%s", prod,
256 				&dev->t10_wwn.unit_serial[0]);
257 	}
258 	buf[off] = 0x2; /* ASCII */
259 	buf[off+1] = 0x1; /* T10 Vendor ID */
260 	buf[off+2] = 0x0;
261 	/* left align Vendor ID and pad with spaces */
262 	memset(&buf[off+4], 0x20, INQUIRY_VENDOR_LEN);
263 	memcpy(&buf[off+4], dev->t10_wwn.vendor,
264 	       strnlen(dev->t10_wwn.vendor, INQUIRY_VENDOR_LEN));
265 	/* Extra Byte for NULL Terminator */
266 	id_len++;
267 	/* Identifier Length */
268 	buf[off+3] = id_len;
269 	/* Header size for Designation descriptor */
270 	len += (id_len + 4);
271 	off += (id_len + 4);
272 
273 	if (1) {
274 		struct t10_alua_lu_gp *lu_gp;
275 		u32 padding, scsi_name_len, scsi_target_len;
276 		u16 lu_gp_id = 0;
277 		u16 tg_pt_gp_id = 0;
278 		u16 tpgt;
279 
280 		tpg = lun->lun_tpg;
281 		/*
282 		 * Relative target port identifer, see spc4r17
283 		 * section 7.7.3.7
284 		 *
285 		 * Get the PROTOCOL IDENTIFIER as defined by spc4r17
286 		 * section 7.5.1 Table 362
287 		 */
288 		buf[off] = tpg->proto_id << 4;
289 		buf[off++] |= 0x1; /* CODE SET == Binary */
290 		buf[off] = 0x80; /* Set PIV=1 */
291 		/* Set ASSOCIATION == target port: 01b */
292 		buf[off] |= 0x10;
293 		/* DESIGNATOR TYPE == Relative target port identifer */
294 		buf[off++] |= 0x4;
295 		off++; /* Skip over Reserved */
296 		buf[off++] = 4; /* DESIGNATOR LENGTH */
297 		/* Skip over Obsolete field in RTPI payload
298 		 * in Table 472 */
299 		off += 2;
300 		put_unaligned_be16(lun->lun_rtpi, &buf[off]);
301 		off += 2;
302 		len += 8; /* Header size + Designation descriptor */
303 		/*
304 		 * Target port group identifier, see spc4r17
305 		 * section 7.7.3.8
306 		 *
307 		 * Get the PROTOCOL IDENTIFIER as defined by spc4r17
308 		 * section 7.5.1 Table 362
309 		 */
310 		spin_lock(&lun->lun_tg_pt_gp_lock);
311 		tg_pt_gp = lun->lun_tg_pt_gp;
312 		if (!tg_pt_gp) {
313 			spin_unlock(&lun->lun_tg_pt_gp_lock);
314 			goto check_lu_gp;
315 		}
316 		tg_pt_gp_id = tg_pt_gp->tg_pt_gp_id;
317 		spin_unlock(&lun->lun_tg_pt_gp_lock);
318 
319 		buf[off] = tpg->proto_id << 4;
320 		buf[off++] |= 0x1; /* CODE SET == Binary */
321 		buf[off] = 0x80; /* Set PIV=1 */
322 		/* Set ASSOCIATION == target port: 01b */
323 		buf[off] |= 0x10;
324 		/* DESIGNATOR TYPE == Target port group identifier */
325 		buf[off++] |= 0x5;
326 		off++; /* Skip over Reserved */
327 		buf[off++] = 4; /* DESIGNATOR LENGTH */
328 		off += 2; /* Skip over Reserved Field */
329 		put_unaligned_be16(tg_pt_gp_id, &buf[off]);
330 		off += 2;
331 		len += 8; /* Header size + Designation descriptor */
332 		/*
333 		 * Logical Unit Group identifier, see spc4r17
334 		 * section 7.7.3.8
335 		 */
336 check_lu_gp:
337 		lu_gp_mem = dev->dev_alua_lu_gp_mem;
338 		if (!lu_gp_mem)
339 			goto check_scsi_name;
340 
341 		spin_lock(&lu_gp_mem->lu_gp_mem_lock);
342 		lu_gp = lu_gp_mem->lu_gp;
343 		if (!lu_gp) {
344 			spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
345 			goto check_scsi_name;
346 		}
347 		lu_gp_id = lu_gp->lu_gp_id;
348 		spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
349 
350 		buf[off++] |= 0x1; /* CODE SET == Binary */
351 		/* DESIGNATOR TYPE == Logical Unit Group identifier */
352 		buf[off++] |= 0x6;
353 		off++; /* Skip over Reserved */
354 		buf[off++] = 4; /* DESIGNATOR LENGTH */
355 		off += 2; /* Skip over Reserved Field */
356 		put_unaligned_be16(lu_gp_id, &buf[off]);
357 		off += 2;
358 		len += 8; /* Header size + Designation descriptor */
359 		/*
360 		 * SCSI name string designator, see spc4r17
361 		 * section 7.7.3.11
362 		 *
363 		 * Get the PROTOCOL IDENTIFIER as defined by spc4r17
364 		 * section 7.5.1 Table 362
365 		 */
366 check_scsi_name:
367 		buf[off] = tpg->proto_id << 4;
368 		buf[off++] |= 0x3; /* CODE SET == UTF-8 */
369 		buf[off] = 0x80; /* Set PIV=1 */
370 		/* Set ASSOCIATION == target port: 01b */
371 		buf[off] |= 0x10;
372 		/* DESIGNATOR TYPE == SCSI name string */
373 		buf[off++] |= 0x8;
374 		off += 2; /* Skip over Reserved and length */
375 		/*
376 		 * SCSI name string identifer containing, $FABRIC_MOD
377 		 * dependent information.  For LIO-Target and iSCSI
378 		 * Target Port, this means "<iSCSI name>,t,0x<TPGT> in
379 		 * UTF-8 encoding.
380 		 */
381 		tpgt = tpg->se_tpg_tfo->tpg_get_tag(tpg);
382 		scsi_name_len = sprintf(&buf[off], "%s,t,0x%04x",
383 					tpg->se_tpg_tfo->tpg_get_wwn(tpg), tpgt);
384 		scsi_name_len += 1 /* Include  NULL terminator */;
385 		/*
386 		 * The null-terminated, null-padded (see 4.4.2) SCSI
387 		 * NAME STRING field contains a UTF-8 format string.
388 		 * The number of bytes in the SCSI NAME STRING field
389 		 * (i.e., the value in the DESIGNATOR LENGTH field)
390 		 * shall be no larger than 256 and shall be a multiple
391 		 * of four.
392 		 */
393 		padding = ((-scsi_name_len) & 3);
394 		if (padding)
395 			scsi_name_len += padding;
396 		if (scsi_name_len > 256)
397 			scsi_name_len = 256;
398 
399 		buf[off-1] = scsi_name_len;
400 		off += scsi_name_len;
401 		/* Header size + Designation descriptor */
402 		len += (scsi_name_len + 4);
403 
404 		/*
405 		 * Target device designator
406 		 */
407 		buf[off] = tpg->proto_id << 4;
408 		buf[off++] |= 0x3; /* CODE SET == UTF-8 */
409 		buf[off] = 0x80; /* Set PIV=1 */
410 		/* Set ASSOCIATION == target device: 10b */
411 		buf[off] |= 0x20;
412 		/* DESIGNATOR TYPE == SCSI name string */
413 		buf[off++] |= 0x8;
414 		off += 2; /* Skip over Reserved and length */
415 		/*
416 		 * SCSI name string identifer containing, $FABRIC_MOD
417 		 * dependent information.  For LIO-Target and iSCSI
418 		 * Target Port, this means "<iSCSI name>" in
419 		 * UTF-8 encoding.
420 		 */
421 		scsi_target_len = sprintf(&buf[off], "%s",
422 					  tpg->se_tpg_tfo->tpg_get_wwn(tpg));
423 		scsi_target_len += 1 /* Include  NULL terminator */;
424 		/*
425 		 * The null-terminated, null-padded (see 4.4.2) SCSI
426 		 * NAME STRING field contains a UTF-8 format string.
427 		 * The number of bytes in the SCSI NAME STRING field
428 		 * (i.e., the value in the DESIGNATOR LENGTH field)
429 		 * shall be no larger than 256 and shall be a multiple
430 		 * of four.
431 		 */
432 		padding = ((-scsi_target_len) & 3);
433 		if (padding)
434 			scsi_target_len += padding;
435 		if (scsi_target_len > 256)
436 			scsi_target_len = 256;
437 
438 		buf[off-1] = scsi_target_len;
439 		off += scsi_target_len;
440 
441 		/* Header size + Designation descriptor */
442 		len += (scsi_target_len + 4);
443 	}
444 	put_unaligned_be16(len, &buf[2]); /* Page Length for VPD 0x83 */
445 	return 0;
446 }
447 EXPORT_SYMBOL(spc_emulate_evpd_83);
448 
449 /* Extended INQUIRY Data VPD Page */
450 static sense_reason_t
451 spc_emulate_evpd_86(struct se_cmd *cmd, unsigned char *buf)
452 {
453 	struct se_device *dev = cmd->se_dev;
454 	struct se_session *sess = cmd->se_sess;
455 
456 	buf[3] = 0x3c;
457 	/*
458 	 * Set GRD_CHK + REF_CHK for TYPE1 protection, or GRD_CHK
459 	 * only for TYPE3 protection.
460 	 */
461 	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
462 		if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT ||
463 		    cmd->se_sess->sess_prot_type == TARGET_DIF_TYPE1_PROT)
464 			buf[4] = 0x5;
465 		else if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE3_PROT ||
466 			 cmd->se_sess->sess_prot_type == TARGET_DIF_TYPE3_PROT)
467 			buf[4] = 0x4;
468 	}
469 
470 	/* logical unit supports type 1 and type 3 protection */
471 	if ((dev->transport->get_device_type(dev) == TYPE_DISK) &&
472 	    (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) &&
473 	    (dev->dev_attrib.pi_prot_type || cmd->se_sess->sess_prot_type)) {
474 		buf[4] |= (0x3 << 3);
475 	}
476 
477 	/* Set HEADSUP, ORDSUP, SIMPSUP */
478 	buf[5] = 0x07;
479 
480 	/* If WriteCache emulation is enabled, set V_SUP */
481 	if (target_check_wce(dev))
482 		buf[6] = 0x01;
483 	/* If an LBA map is present set R_SUP */
484 	spin_lock(&cmd->se_dev->t10_alua.lba_map_lock);
485 	if (!list_empty(&dev->t10_alua.lba_map_list))
486 		buf[8] = 0x10;
487 	spin_unlock(&cmd->se_dev->t10_alua.lba_map_lock);
488 	return 0;
489 }
490 
491 /* Block Limits VPD page */
492 static sense_reason_t
493 spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf)
494 {
495 	struct se_device *dev = cmd->se_dev;
496 	u32 mtl = 0;
497 	int have_tp = 0, opt, min;
498 
499 	/*
500 	 * Following spc3r22 section 6.5.3 Block Limits VPD page, when
501 	 * emulate_tpu=1 or emulate_tpws=1 we will be expect a
502 	 * different page length for Thin Provisioning.
503 	 */
504 	if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws)
505 		have_tp = 1;
506 
507 	buf[0] = dev->transport->get_device_type(dev);
508 	buf[3] = have_tp ? 0x3c : 0x10;
509 
510 	/* Set WSNZ to 1 */
511 	buf[4] = 0x01;
512 	/*
513 	 * Set MAXIMUM COMPARE AND WRITE LENGTH
514 	 */
515 	if (dev->dev_attrib.emulate_caw)
516 		buf[5] = 0x01;
517 
518 	/*
519 	 * Set OPTIMAL TRANSFER LENGTH GRANULARITY
520 	 */
521 	if (dev->transport->get_io_min && (min = dev->transport->get_io_min(dev)))
522 		put_unaligned_be16(min / dev->dev_attrib.block_size, &buf[6]);
523 	else
524 		put_unaligned_be16(1, &buf[6]);
525 
526 	/*
527 	 * Set MAXIMUM TRANSFER LENGTH
528 	 *
529 	 * XXX: Currently assumes single PAGE_SIZE per scatterlist for fabrics
530 	 * enforcing maximum HW scatter-gather-list entry limit
531 	 */
532 	if (cmd->se_tfo->max_data_sg_nents) {
533 		mtl = (cmd->se_tfo->max_data_sg_nents * PAGE_SIZE) /
534 		       dev->dev_attrib.block_size;
535 	}
536 	put_unaligned_be32(min_not_zero(mtl, dev->dev_attrib.hw_max_sectors), &buf[8]);
537 
538 	/*
539 	 * Set OPTIMAL TRANSFER LENGTH
540 	 */
541 	if (dev->transport->get_io_opt && (opt = dev->transport->get_io_opt(dev)))
542 		put_unaligned_be32(opt / dev->dev_attrib.block_size, &buf[12]);
543 	else
544 		put_unaligned_be32(dev->dev_attrib.optimal_sectors, &buf[12]);
545 
546 	/*
547 	 * Exit now if we don't support TP.
548 	 */
549 	if (!have_tp)
550 		goto max_write_same;
551 
552 	/*
553 	 * Set MAXIMUM UNMAP LBA COUNT
554 	 */
555 	put_unaligned_be32(dev->dev_attrib.max_unmap_lba_count, &buf[20]);
556 
557 	/*
558 	 * Set MAXIMUM UNMAP BLOCK DESCRIPTOR COUNT
559 	 */
560 	put_unaligned_be32(dev->dev_attrib.max_unmap_block_desc_count,
561 			   &buf[24]);
562 
563 	/*
564 	 * Set OPTIMAL UNMAP GRANULARITY
565 	 */
566 	put_unaligned_be32(dev->dev_attrib.unmap_granularity, &buf[28]);
567 
568 	/*
569 	 * UNMAP GRANULARITY ALIGNMENT
570 	 */
571 	put_unaligned_be32(dev->dev_attrib.unmap_granularity_alignment,
572 			   &buf[32]);
573 	if (dev->dev_attrib.unmap_granularity_alignment != 0)
574 		buf[32] |= 0x80; /* Set the UGAVALID bit */
575 
576 	/*
577 	 * MAXIMUM WRITE SAME LENGTH
578 	 */
579 max_write_same:
580 	put_unaligned_be64(dev->dev_attrib.max_write_same_len, &buf[36]);
581 
582 	return 0;
583 }
584 
585 /* Block Device Characteristics VPD page */
586 static sense_reason_t
587 spc_emulate_evpd_b1(struct se_cmd *cmd, unsigned char *buf)
588 {
589 	struct se_device *dev = cmd->se_dev;
590 
591 	buf[0] = dev->transport->get_device_type(dev);
592 	buf[3] = 0x3c;
593 	buf[5] = dev->dev_attrib.is_nonrot ? 1 : 0;
594 
595 	return 0;
596 }
597 
598 /* Thin Provisioning VPD */
599 static sense_reason_t
600 spc_emulate_evpd_b2(struct se_cmd *cmd, unsigned char *buf)
601 {
602 	struct se_device *dev = cmd->se_dev;
603 
604 	/*
605 	 * From spc3r22 section 6.5.4 Thin Provisioning VPD page:
606 	 *
607 	 * The PAGE LENGTH field is defined in SPC-4. If the DP bit is set to
608 	 * zero, then the page length shall be set to 0004h.  If the DP bit
609 	 * is set to one, then the page length shall be set to the value
610 	 * defined in table 162.
611 	 */
612 	buf[0] = dev->transport->get_device_type(dev);
613 
614 	/*
615 	 * Set Hardcoded length mentioned above for DP=0
616 	 */
617 	put_unaligned_be16(0x0004, &buf[2]);
618 
619 	/*
620 	 * The THRESHOLD EXPONENT field indicates the threshold set size in
621 	 * LBAs as a power of 2 (i.e., the threshold set size is equal to
622 	 * 2(threshold exponent)).
623 	 *
624 	 * Note that this is currently set to 0x00 as mkp says it will be
625 	 * changing again.  We can enable this once it has settled in T10
626 	 * and is actually used by Linux/SCSI ML code.
627 	 */
628 	buf[4] = 0x00;
629 
630 	/*
631 	 * A TPU bit set to one indicates that the device server supports
632 	 * the UNMAP command (see 5.25). A TPU bit set to zero indicates
633 	 * that the device server does not support the UNMAP command.
634 	 */
635 	if (dev->dev_attrib.emulate_tpu != 0)
636 		buf[5] = 0x80;
637 
638 	/*
639 	 * A TPWS bit set to one indicates that the device server supports
640 	 * the use of the WRITE SAME (16) command (see 5.42) to unmap LBAs.
641 	 * A TPWS bit set to zero indicates that the device server does not
642 	 * support the use of the WRITE SAME (16) command to unmap LBAs.
643 	 */
644 	if (dev->dev_attrib.emulate_tpws != 0)
645 		buf[5] |= 0x40 | 0x20;
646 
647 	/*
648 	 * The unmap_zeroes_data set means that the underlying device supports
649 	 * REQ_OP_DISCARD and has the discard_zeroes_data bit set. This
650 	 * satisfies the SBC requirements for LBPRZ, meaning that a subsequent
651 	 * read will return zeroes after an UNMAP or WRITE SAME (16) to an LBA
652 	 * See sbc4r36 6.6.4.
653 	 */
654 	if (((dev->dev_attrib.emulate_tpu != 0) ||
655 	     (dev->dev_attrib.emulate_tpws != 0)) &&
656 	     (dev->dev_attrib.unmap_zeroes_data != 0))
657 		buf[5] |= 0x04;
658 
659 	return 0;
660 }
661 
662 /* Referrals VPD page */
663 static sense_reason_t
664 spc_emulate_evpd_b3(struct se_cmd *cmd, unsigned char *buf)
665 {
666 	struct se_device *dev = cmd->se_dev;
667 
668 	buf[0] = dev->transport->get_device_type(dev);
669 	buf[3] = 0x0c;
670 	put_unaligned_be32(dev->t10_alua.lba_map_segment_size, &buf[8]);
671 	put_unaligned_be32(dev->t10_alua.lba_map_segment_multiplier, &buf[12]);
672 
673 	return 0;
674 }
675 
676 static sense_reason_t
677 spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf);
678 
679 static struct {
680 	uint8_t		page;
681 	sense_reason_t	(*emulate)(struct se_cmd *, unsigned char *);
682 } evpd_handlers[] = {
683 	{ .page = 0x00, .emulate = spc_emulate_evpd_00 },
684 	{ .page = 0x80, .emulate = spc_emulate_evpd_80 },
685 	{ .page = 0x83, .emulate = spc_emulate_evpd_83 },
686 	{ .page = 0x86, .emulate = spc_emulate_evpd_86 },
687 	{ .page = 0xb0, .emulate = spc_emulate_evpd_b0 },
688 	{ .page = 0xb1, .emulate = spc_emulate_evpd_b1 },
689 	{ .page = 0xb2, .emulate = spc_emulate_evpd_b2 },
690 	{ .page = 0xb3, .emulate = spc_emulate_evpd_b3 },
691 };
692 
693 /* supported vital product data pages */
694 static sense_reason_t
695 spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf)
696 {
697 	int p;
698 
699 	/*
700 	 * Only report the INQUIRY EVPD=1 pages after a valid NAA
701 	 * Registered Extended LUN WWN has been set via ConfigFS
702 	 * during device creation/restart.
703 	 */
704 	if (cmd->se_dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL) {
705 		buf[3] = ARRAY_SIZE(evpd_handlers);
706 		for (p = 0; p < ARRAY_SIZE(evpd_handlers); ++p)
707 			buf[p + 4] = evpd_handlers[p].page;
708 	}
709 
710 	return 0;
711 }
712 
713 static sense_reason_t
714 spc_emulate_inquiry(struct se_cmd *cmd)
715 {
716 	struct se_device *dev = cmd->se_dev;
717 	struct se_portal_group *tpg = cmd->se_lun->lun_tpg;
718 	unsigned char *rbuf;
719 	unsigned char *cdb = cmd->t_task_cdb;
720 	unsigned char *buf;
721 	sense_reason_t ret;
722 	int p;
723 	int len = 0;
724 
725 	buf = kzalloc(SE_INQUIRY_BUF, GFP_KERNEL);
726 	if (!buf) {
727 		pr_err("Unable to allocate response buffer for INQUIRY\n");
728 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
729 	}
730 
731 	if (dev == rcu_access_pointer(tpg->tpg_virt_lun0->lun_se_dev))
732 		buf[0] = 0x3f; /* Not connected */
733 	else
734 		buf[0] = dev->transport->get_device_type(dev);
735 
736 	if (!(cdb[1] & 0x1)) {
737 		if (cdb[2]) {
738 			pr_err("INQUIRY with EVPD==0 but PAGE CODE=%02x\n",
739 			       cdb[2]);
740 			ret = TCM_INVALID_CDB_FIELD;
741 			goto out;
742 		}
743 
744 		ret = spc_emulate_inquiry_std(cmd, buf);
745 		len = buf[4] + 5;
746 		goto out;
747 	}
748 
749 	for (p = 0; p < ARRAY_SIZE(evpd_handlers); ++p) {
750 		if (cdb[2] == evpd_handlers[p].page) {
751 			buf[1] = cdb[2];
752 			ret = evpd_handlers[p].emulate(cmd, buf);
753 			len = get_unaligned_be16(&buf[2]) + 4;
754 			goto out;
755 		}
756 	}
757 
758 	pr_err("Unknown VPD Code: 0x%02x\n", cdb[2]);
759 	ret = TCM_INVALID_CDB_FIELD;
760 
761 out:
762 	rbuf = transport_kmap_data_sg(cmd);
763 	if (rbuf) {
764 		memcpy(rbuf, buf, min_t(u32, SE_INQUIRY_BUF, cmd->data_length));
765 		transport_kunmap_data_sg(cmd);
766 	}
767 	kfree(buf);
768 
769 	if (!ret)
770 		target_complete_cmd_with_length(cmd, GOOD, len);
771 	return ret;
772 }
773 
774 static int spc_modesense_rwrecovery(struct se_cmd *cmd, u8 pc, u8 *p)
775 {
776 	p[0] = 0x01;
777 	p[1] = 0x0a;
778 
779 	/* No changeable values for now */
780 	if (pc == 1)
781 		goto out;
782 
783 out:
784 	return 12;
785 }
786 
787 static int spc_modesense_control(struct se_cmd *cmd, u8 pc, u8 *p)
788 {
789 	struct se_device *dev = cmd->se_dev;
790 	struct se_session *sess = cmd->se_sess;
791 
792 	p[0] = 0x0a;
793 	p[1] = 0x0a;
794 
795 	/* No changeable values for now */
796 	if (pc == 1)
797 		goto out;
798 
799 	/* GLTSD: No implicit save of log parameters */
800 	p[2] = (1 << 1);
801 	if (target_sense_desc_format(dev))
802 		/* D_SENSE: Descriptor format sense data for 64bit sectors */
803 		p[2] |= (1 << 2);
804 
805 	/*
806 	 * From spc4r23, 7.4.7 Control mode page
807 	 *
808 	 * The QUEUE ALGORITHM MODIFIER field (see table 368) specifies
809 	 * restrictions on the algorithm used for reordering commands
810 	 * having the SIMPLE task attribute (see SAM-4).
811 	 *
812 	 *                    Table 368 -- QUEUE ALGORITHM MODIFIER field
813 	 *                         Code      Description
814 	 *                          0h       Restricted reordering
815 	 *                          1h       Unrestricted reordering allowed
816 	 *                          2h to 7h    Reserved
817 	 *                          8h to Fh    Vendor specific
818 	 *
819 	 * A value of zero in the QUEUE ALGORITHM MODIFIER field specifies that
820 	 * the device server shall order the processing sequence of commands
821 	 * having the SIMPLE task attribute such that data integrity is maintained
822 	 * for that I_T nexus (i.e., if the transmission of new SCSI transport protocol
823 	 * requests is halted at any time, the final value of all data observable
824 	 * on the medium shall be the same as if all the commands had been processed
825 	 * with the ORDERED task attribute).
826 	 *
827 	 * A value of one in the QUEUE ALGORITHM MODIFIER field specifies that the
828 	 * device server may reorder the processing sequence of commands having the
829 	 * SIMPLE task attribute in any manner. Any data integrity exposures related to
830 	 * command sequence order shall be explicitly handled by the application client
831 	 * through the selection of appropriate ommands and task attributes.
832 	 */
833 	p[3] = (dev->dev_attrib.emulate_rest_reord == 1) ? 0x00 : 0x10;
834 	/*
835 	 * From spc4r17, section 7.4.6 Control mode Page
836 	 *
837 	 * Unit Attention interlocks control (UN_INTLCK_CTRL) to code 00b
838 	 *
839 	 * 00b: The logical unit shall clear any unit attention condition
840 	 * reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
841 	 * status and shall not establish a unit attention condition when a com-
842 	 * mand is completed with BUSY, TASK SET FULL, or RESERVATION CONFLICT
843 	 * status.
844 	 *
845 	 * 10b: The logical unit shall not clear any unit attention condition
846 	 * reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
847 	 * status and shall not establish a unit attention condition when
848 	 * a command is completed with BUSY, TASK SET FULL, or RESERVATION
849 	 * CONFLICT status.
850 	 *
851 	 * 11b a The logical unit shall not clear any unit attention condition
852 	 * reported in the same I_T_L_Q nexus transaction as a CHECK CONDITION
853 	 * status and shall establish a unit attention condition for the
854 	 * initiator port associated with the I_T nexus on which the BUSY,
855 	 * TASK SET FULL, or RESERVATION CONFLICT status is being returned.
856 	 * Depending on the status, the additional sense code shall be set to
857 	 * PREVIOUS BUSY STATUS, PREVIOUS TASK SET FULL STATUS, or PREVIOUS
858 	 * RESERVATION CONFLICT STATUS. Until it is cleared by a REQUEST SENSE
859 	 * command, a unit attention condition shall be established only once
860 	 * for a BUSY, TASK SET FULL, or RESERVATION CONFLICT status regardless
861 	 * to the number of commands completed with one of those status codes.
862 	 */
863 	p[4] = (dev->dev_attrib.emulate_ua_intlck_ctrl == 2) ? 0x30 :
864 	       (dev->dev_attrib.emulate_ua_intlck_ctrl == 1) ? 0x20 : 0x00;
865 	/*
866 	 * From spc4r17, section 7.4.6 Control mode Page
867 	 *
868 	 * Task Aborted Status (TAS) bit set to zero.
869 	 *
870 	 * A task aborted status (TAS) bit set to zero specifies that aborted
871 	 * tasks shall be terminated by the device server without any response
872 	 * to the application client. A TAS bit set to one specifies that tasks
873 	 * aborted by the actions of an I_T nexus other than the I_T nexus on
874 	 * which the command was received shall be completed with TASK ABORTED
875 	 * status (see SAM-4).
876 	 */
877 	p[5] = (dev->dev_attrib.emulate_tas) ? 0x40 : 0x00;
878 	/*
879 	 * From spc4r30, section 7.5.7 Control mode page
880 	 *
881 	 * Application Tag Owner (ATO) bit set to one.
882 	 *
883 	 * If the ATO bit is set to one the device server shall not modify the
884 	 * LOGICAL BLOCK APPLICATION TAG field and, depending on the protection
885 	 * type, shall not modify the contents of the LOGICAL BLOCK REFERENCE
886 	 * TAG field.
887 	 */
888 	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
889 		if (dev->dev_attrib.pi_prot_type || sess->sess_prot_type)
890 			p[5] |= 0x80;
891 	}
892 
893 	p[8] = 0xff;
894 	p[9] = 0xff;
895 	p[11] = 30;
896 
897 out:
898 	return 12;
899 }
900 
901 static int spc_modesense_caching(struct se_cmd *cmd, u8 pc, u8 *p)
902 {
903 	struct se_device *dev = cmd->se_dev;
904 
905 	p[0] = 0x08;
906 	p[1] = 0x12;
907 
908 	/* No changeable values for now */
909 	if (pc == 1)
910 		goto out;
911 
912 	if (target_check_wce(dev))
913 		p[2] = 0x04; /* Write Cache Enable */
914 	p[12] = 0x20; /* Disabled Read Ahead */
915 
916 out:
917 	return 20;
918 }
919 
920 static int spc_modesense_informational_exceptions(struct se_cmd *cmd, u8 pc, unsigned char *p)
921 {
922 	p[0] = 0x1c;
923 	p[1] = 0x0a;
924 
925 	/* No changeable values for now */
926 	if (pc == 1)
927 		goto out;
928 
929 out:
930 	return 12;
931 }
932 
933 static struct {
934 	uint8_t		page;
935 	uint8_t		subpage;
936 	int		(*emulate)(struct se_cmd *, u8, unsigned char *);
937 } modesense_handlers[] = {
938 	{ .page = 0x01, .subpage = 0x00, .emulate = spc_modesense_rwrecovery },
939 	{ .page = 0x08, .subpage = 0x00, .emulate = spc_modesense_caching },
940 	{ .page = 0x0a, .subpage = 0x00, .emulate = spc_modesense_control },
941 	{ .page = 0x1c, .subpage = 0x00, .emulate = spc_modesense_informational_exceptions },
942 };
943 
944 static void spc_modesense_write_protect(unsigned char *buf, int type)
945 {
946 	/*
947 	 * I believe that the WP bit (bit 7) in the mode header is the same for
948 	 * all device types..
949 	 */
950 	switch (type) {
951 	case TYPE_DISK:
952 	case TYPE_TAPE:
953 	default:
954 		buf[0] |= 0x80; /* WP bit */
955 		break;
956 	}
957 }
958 
959 static void spc_modesense_dpofua(unsigned char *buf, int type)
960 {
961 	switch (type) {
962 	case TYPE_DISK:
963 		buf[0] |= 0x10; /* DPOFUA bit */
964 		break;
965 	default:
966 		break;
967 	}
968 }
969 
970 static int spc_modesense_blockdesc(unsigned char *buf, u64 blocks, u32 block_size)
971 {
972 	*buf++ = 8;
973 	put_unaligned_be32(min(blocks, 0xffffffffull), buf);
974 	buf += 4;
975 	put_unaligned_be32(block_size, buf);
976 	return 9;
977 }
978 
979 static int spc_modesense_long_blockdesc(unsigned char *buf, u64 blocks, u32 block_size)
980 {
981 	if (blocks <= 0xffffffff)
982 		return spc_modesense_blockdesc(buf + 3, blocks, block_size) + 3;
983 
984 	*buf++ = 1;		/* LONGLBA */
985 	buf += 2;
986 	*buf++ = 16;
987 	put_unaligned_be64(blocks, buf);
988 	buf += 12;
989 	put_unaligned_be32(block_size, buf);
990 
991 	return 17;
992 }
993 
994 static sense_reason_t spc_emulate_modesense(struct se_cmd *cmd)
995 {
996 	struct se_device *dev = cmd->se_dev;
997 	char *cdb = cmd->t_task_cdb;
998 	unsigned char buf[SE_MODE_PAGE_BUF], *rbuf;
999 	int type = dev->transport->get_device_type(dev);
1000 	int ten = (cmd->t_task_cdb[0] == MODE_SENSE_10);
1001 	bool dbd = !!(cdb[1] & 0x08);
1002 	bool llba = ten ? !!(cdb[1] & 0x10) : false;
1003 	u8 pc = cdb[2] >> 6;
1004 	u8 page = cdb[2] & 0x3f;
1005 	u8 subpage = cdb[3];
1006 	int length = 0;
1007 	int ret;
1008 	int i;
1009 
1010 	memset(buf, 0, SE_MODE_PAGE_BUF);
1011 
1012 	/*
1013 	 * Skip over MODE DATA LENGTH + MEDIUM TYPE fields to byte 3 for
1014 	 * MODE_SENSE_10 and byte 2 for MODE_SENSE (6).
1015 	 */
1016 	length = ten ? 3 : 2;
1017 
1018 	/* DEVICE-SPECIFIC PARAMETER */
1019 	if (cmd->se_lun->lun_access_ro || target_lun_is_rdonly(cmd))
1020 		spc_modesense_write_protect(&buf[length], type);
1021 
1022 	/*
1023 	 * SBC only allows us to enable FUA and DPO together.  Fortunately
1024 	 * DPO is explicitly specified as a hint, so a noop is a perfectly
1025 	 * valid implementation.
1026 	 */
1027 	if (target_check_fua(dev))
1028 		spc_modesense_dpofua(&buf[length], type);
1029 
1030 	++length;
1031 
1032 	/* BLOCK DESCRIPTOR */
1033 
1034 	/*
1035 	 * For now we only include a block descriptor for disk (SBC)
1036 	 * devices; other command sets use a slightly different format.
1037 	 */
1038 	if (!dbd && type == TYPE_DISK) {
1039 		u64 blocks = dev->transport->get_blocks(dev);
1040 		u32 block_size = dev->dev_attrib.block_size;
1041 
1042 		if (ten) {
1043 			if (llba) {
1044 				length += spc_modesense_long_blockdesc(&buf[length],
1045 								       blocks, block_size);
1046 			} else {
1047 				length += 3;
1048 				length += spc_modesense_blockdesc(&buf[length],
1049 								  blocks, block_size);
1050 			}
1051 		} else {
1052 			length += spc_modesense_blockdesc(&buf[length], blocks,
1053 							  block_size);
1054 		}
1055 	} else {
1056 		if (ten)
1057 			length += 4;
1058 		else
1059 			length += 1;
1060 	}
1061 
1062 	if (page == 0x3f) {
1063 		if (subpage != 0x00 && subpage != 0xff) {
1064 			pr_warn("MODE_SENSE: Invalid subpage code: 0x%02x\n", subpage);
1065 			return TCM_INVALID_CDB_FIELD;
1066 		}
1067 
1068 		for (i = 0; i < ARRAY_SIZE(modesense_handlers); ++i) {
1069 			/*
1070 			 * Tricky way to say all subpage 00h for
1071 			 * subpage==0, all subpages for subpage==0xff
1072 			 * (and we just checked above that those are
1073 			 * the only two possibilities).
1074 			 */
1075 			if ((modesense_handlers[i].subpage & ~subpage) == 0) {
1076 				ret = modesense_handlers[i].emulate(cmd, pc, &buf[length]);
1077 				if (!ten && length + ret >= 255)
1078 					break;
1079 				length += ret;
1080 			}
1081 		}
1082 
1083 		goto set_length;
1084 	}
1085 
1086 	for (i = 0; i < ARRAY_SIZE(modesense_handlers); ++i)
1087 		if (modesense_handlers[i].page == page &&
1088 		    modesense_handlers[i].subpage == subpage) {
1089 			length += modesense_handlers[i].emulate(cmd, pc, &buf[length]);
1090 			goto set_length;
1091 		}
1092 
1093 	/*
1094 	 * We don't intend to implement:
1095 	 *  - obsolete page 03h "format parameters" (checked by Solaris)
1096 	 */
1097 	if (page != 0x03)
1098 		pr_err("MODE SENSE: unimplemented page/subpage: 0x%02x/0x%02x\n",
1099 		       page, subpage);
1100 
1101 	return TCM_UNKNOWN_MODE_PAGE;
1102 
1103 set_length:
1104 	if (ten)
1105 		put_unaligned_be16(length - 2, buf);
1106 	else
1107 		buf[0] = length - 1;
1108 
1109 	rbuf = transport_kmap_data_sg(cmd);
1110 	if (rbuf) {
1111 		memcpy(rbuf, buf, min_t(u32, SE_MODE_PAGE_BUF, cmd->data_length));
1112 		transport_kunmap_data_sg(cmd);
1113 	}
1114 
1115 	target_complete_cmd_with_length(cmd, GOOD, length);
1116 	return 0;
1117 }
1118 
1119 static sense_reason_t spc_emulate_modeselect(struct se_cmd *cmd)
1120 {
1121 	char *cdb = cmd->t_task_cdb;
1122 	bool ten = cdb[0] == MODE_SELECT_10;
1123 	int off = ten ? 8 : 4;
1124 	bool pf = !!(cdb[1] & 0x10);
1125 	u8 page, subpage;
1126 	unsigned char *buf;
1127 	unsigned char tbuf[SE_MODE_PAGE_BUF];
1128 	int length;
1129 	sense_reason_t ret = 0;
1130 	int i;
1131 
1132 	if (!cmd->data_length) {
1133 		target_complete_cmd(cmd, GOOD);
1134 		return 0;
1135 	}
1136 
1137 	if (cmd->data_length < off + 2)
1138 		return TCM_PARAMETER_LIST_LENGTH_ERROR;
1139 
1140 	buf = transport_kmap_data_sg(cmd);
1141 	if (!buf)
1142 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1143 
1144 	if (!pf) {
1145 		ret = TCM_INVALID_CDB_FIELD;
1146 		goto out;
1147 	}
1148 
1149 	page = buf[off] & 0x3f;
1150 	subpage = buf[off] & 0x40 ? buf[off + 1] : 0;
1151 
1152 	for (i = 0; i < ARRAY_SIZE(modesense_handlers); ++i)
1153 		if (modesense_handlers[i].page == page &&
1154 		    modesense_handlers[i].subpage == subpage) {
1155 			memset(tbuf, 0, SE_MODE_PAGE_BUF);
1156 			length = modesense_handlers[i].emulate(cmd, 0, tbuf);
1157 			goto check_contents;
1158 		}
1159 
1160 	ret = TCM_UNKNOWN_MODE_PAGE;
1161 	goto out;
1162 
1163 check_contents:
1164 	if (cmd->data_length < off + length) {
1165 		ret = TCM_PARAMETER_LIST_LENGTH_ERROR;
1166 		goto out;
1167 	}
1168 
1169 	if (memcmp(buf + off, tbuf, length))
1170 		ret = TCM_INVALID_PARAMETER_LIST;
1171 
1172 out:
1173 	transport_kunmap_data_sg(cmd);
1174 
1175 	if (!ret)
1176 		target_complete_cmd(cmd, GOOD);
1177 	return ret;
1178 }
1179 
1180 static sense_reason_t spc_emulate_request_sense(struct se_cmd *cmd)
1181 {
1182 	unsigned char *cdb = cmd->t_task_cdb;
1183 	unsigned char *rbuf;
1184 	u8 ua_asc = 0, ua_ascq = 0;
1185 	unsigned char buf[SE_SENSE_BUF];
1186 	bool desc_format = target_sense_desc_format(cmd->se_dev);
1187 
1188 	memset(buf, 0, SE_SENSE_BUF);
1189 
1190 	if (cdb[1] & 0x01) {
1191 		pr_err("REQUEST_SENSE description emulation not"
1192 			" supported\n");
1193 		return TCM_INVALID_CDB_FIELD;
1194 	}
1195 
1196 	rbuf = transport_kmap_data_sg(cmd);
1197 	if (!rbuf)
1198 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1199 
1200 	if (!core_scsi3_ua_clear_for_request_sense(cmd, &ua_asc, &ua_ascq))
1201 		scsi_build_sense_buffer(desc_format, buf, UNIT_ATTENTION,
1202 					ua_asc, ua_ascq);
1203 	else
1204 		scsi_build_sense_buffer(desc_format, buf, NO_SENSE, 0x0, 0x0);
1205 
1206 	memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
1207 	transport_kunmap_data_sg(cmd);
1208 
1209 	target_complete_cmd(cmd, GOOD);
1210 	return 0;
1211 }
1212 
1213 sense_reason_t spc_emulate_report_luns(struct se_cmd *cmd)
1214 {
1215 	struct se_dev_entry *deve;
1216 	struct se_session *sess = cmd->se_sess;
1217 	struct se_node_acl *nacl;
1218 	struct scsi_lun slun;
1219 	unsigned char *buf;
1220 	u32 lun_count = 0, offset = 8;
1221 	__be32 len;
1222 
1223 	buf = transport_kmap_data_sg(cmd);
1224 	if (cmd->data_length && !buf)
1225 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1226 
1227 	/*
1228 	 * If no struct se_session pointer is present, this struct se_cmd is
1229 	 * coming via a target_core_mod PASSTHROUGH op, and not through
1230 	 * a $FABRIC_MOD.  In that case, report LUN=0 only.
1231 	 */
1232 	if (!sess)
1233 		goto done;
1234 
1235 	nacl = sess->se_node_acl;
1236 
1237 	rcu_read_lock();
1238 	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
1239 		/*
1240 		 * We determine the correct LUN LIST LENGTH even once we
1241 		 * have reached the initial allocation length.
1242 		 * See SPC2-R20 7.19.
1243 		 */
1244 		lun_count++;
1245 		if (offset >= cmd->data_length)
1246 			continue;
1247 
1248 		int_to_scsilun(deve->mapped_lun, &slun);
1249 		memcpy(buf + offset, &slun,
1250 		       min(8u, cmd->data_length - offset));
1251 		offset += 8;
1252 	}
1253 	rcu_read_unlock();
1254 
1255 	/*
1256 	 * See SPC3 r07, page 159.
1257 	 */
1258 done:
1259 	/*
1260 	 * If no LUNs are accessible, report virtual LUN 0.
1261 	 */
1262 	if (lun_count == 0) {
1263 		int_to_scsilun(0, &slun);
1264 		if (cmd->data_length > 8)
1265 			memcpy(buf + offset, &slun,
1266 			       min(8u, cmd->data_length - offset));
1267 		lun_count = 1;
1268 	}
1269 
1270 	if (buf) {
1271 		len = cpu_to_be32(lun_count * 8);
1272 		memcpy(buf, &len, min_t(int, sizeof len, cmd->data_length));
1273 		transport_kunmap_data_sg(cmd);
1274 	}
1275 
1276 	target_complete_cmd_with_length(cmd, GOOD, 8 + lun_count * 8);
1277 	return 0;
1278 }
1279 EXPORT_SYMBOL(spc_emulate_report_luns);
1280 
1281 static sense_reason_t
1282 spc_emulate_testunitready(struct se_cmd *cmd)
1283 {
1284 	target_complete_cmd(cmd, GOOD);
1285 	return 0;
1286 }
1287 
1288 sense_reason_t
1289 spc_parse_cdb(struct se_cmd *cmd, unsigned int *size)
1290 {
1291 	struct se_device *dev = cmd->se_dev;
1292 	unsigned char *cdb = cmd->t_task_cdb;
1293 
1294 	if (!dev->dev_attrib.emulate_pr &&
1295 	    ((cdb[0] == PERSISTENT_RESERVE_IN) ||
1296 	     (cdb[0] == PERSISTENT_RESERVE_OUT) ||
1297 	     (cdb[0] == RELEASE || cdb[0] == RELEASE_10) ||
1298 	     (cdb[0] == RESERVE || cdb[0] == RESERVE_10))) {
1299 		return TCM_UNSUPPORTED_SCSI_OPCODE;
1300 	}
1301 
1302 	switch (cdb[0]) {
1303 	case MODE_SELECT:
1304 		*size = cdb[4];
1305 		cmd->execute_cmd = spc_emulate_modeselect;
1306 		break;
1307 	case MODE_SELECT_10:
1308 		*size = get_unaligned_be16(&cdb[7]);
1309 		cmd->execute_cmd = spc_emulate_modeselect;
1310 		break;
1311 	case MODE_SENSE:
1312 		*size = cdb[4];
1313 		cmd->execute_cmd = spc_emulate_modesense;
1314 		break;
1315 	case MODE_SENSE_10:
1316 		*size = get_unaligned_be16(&cdb[7]);
1317 		cmd->execute_cmd = spc_emulate_modesense;
1318 		break;
1319 	case LOG_SELECT:
1320 	case LOG_SENSE:
1321 		*size = get_unaligned_be16(&cdb[7]);
1322 		break;
1323 	case PERSISTENT_RESERVE_IN:
1324 		*size = get_unaligned_be16(&cdb[7]);
1325 		cmd->execute_cmd = target_scsi3_emulate_pr_in;
1326 		break;
1327 	case PERSISTENT_RESERVE_OUT:
1328 		*size = get_unaligned_be32(&cdb[5]);
1329 		cmd->execute_cmd = target_scsi3_emulate_pr_out;
1330 		break;
1331 	case RELEASE:
1332 	case RELEASE_10:
1333 		if (cdb[0] == RELEASE_10)
1334 			*size = get_unaligned_be16(&cdb[7]);
1335 		else
1336 			*size = cmd->data_length;
1337 
1338 		cmd->execute_cmd = target_scsi2_reservation_release;
1339 		break;
1340 	case RESERVE:
1341 	case RESERVE_10:
1342 		/*
1343 		 * The SPC-2 RESERVE does not contain a size in the SCSI CDB.
1344 		 * Assume the passthrough or $FABRIC_MOD will tell us about it.
1345 		 */
1346 		if (cdb[0] == RESERVE_10)
1347 			*size = get_unaligned_be16(&cdb[7]);
1348 		else
1349 			*size = cmd->data_length;
1350 
1351 		cmd->execute_cmd = target_scsi2_reservation_reserve;
1352 		break;
1353 	case REQUEST_SENSE:
1354 		*size = cdb[4];
1355 		cmd->execute_cmd = spc_emulate_request_sense;
1356 		break;
1357 	case INQUIRY:
1358 		*size = get_unaligned_be16(&cdb[3]);
1359 
1360 		/*
1361 		 * Do implicit HEAD_OF_QUEUE processing for INQUIRY.
1362 		 * See spc4r17 section 5.3
1363 		 */
1364 		cmd->sam_task_attr = TCM_HEAD_TAG;
1365 		cmd->execute_cmd = spc_emulate_inquiry;
1366 		break;
1367 	case SECURITY_PROTOCOL_IN:
1368 	case SECURITY_PROTOCOL_OUT:
1369 		*size = get_unaligned_be32(&cdb[6]);
1370 		break;
1371 	case EXTENDED_COPY:
1372 		*size = get_unaligned_be32(&cdb[10]);
1373 		cmd->execute_cmd = target_do_xcopy;
1374 		break;
1375 	case RECEIVE_COPY_RESULTS:
1376 		*size = get_unaligned_be32(&cdb[10]);
1377 		cmd->execute_cmd = target_do_receive_copy_results;
1378 		break;
1379 	case READ_ATTRIBUTE:
1380 	case WRITE_ATTRIBUTE:
1381 		*size = get_unaligned_be32(&cdb[10]);
1382 		break;
1383 	case RECEIVE_DIAGNOSTIC:
1384 	case SEND_DIAGNOSTIC:
1385 		*size = get_unaligned_be16(&cdb[3]);
1386 		break;
1387 	case WRITE_BUFFER:
1388 		*size = get_unaligned_be24(&cdb[6]);
1389 		break;
1390 	case REPORT_LUNS:
1391 		cmd->execute_cmd = spc_emulate_report_luns;
1392 		*size = get_unaligned_be32(&cdb[6]);
1393 		/*
1394 		 * Do implicit HEAD_OF_QUEUE processing for REPORT_LUNS
1395 		 * See spc4r17 section 5.3
1396 		 */
1397 		cmd->sam_task_attr = TCM_HEAD_TAG;
1398 		break;
1399 	case TEST_UNIT_READY:
1400 		cmd->execute_cmd = spc_emulate_testunitready;
1401 		*size = 0;
1402 		break;
1403 	case MAINTENANCE_IN:
1404 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
1405 			/*
1406 			 * MAINTENANCE_IN from SCC-2
1407 			 * Check for emulated MI_REPORT_TARGET_PGS
1408 			 */
1409 			if ((cdb[1] & 0x1f) == MI_REPORT_TARGET_PGS) {
1410 				cmd->execute_cmd =
1411 					target_emulate_report_target_port_groups;
1412 			}
1413 			*size = get_unaligned_be32(&cdb[6]);
1414 		} else {
1415 			/*
1416 			 * GPCMD_SEND_KEY from multi media commands
1417 			 */
1418 			*size = get_unaligned_be16(&cdb[8]);
1419 		}
1420 		break;
1421 	case MAINTENANCE_OUT:
1422 		if (dev->transport->get_device_type(dev) != TYPE_ROM) {
1423 			/*
1424 			 * MAINTENANCE_OUT from SCC-2
1425 			 * Check for emulated MO_SET_TARGET_PGS.
1426 			 */
1427 			if (cdb[1] == MO_SET_TARGET_PGS) {
1428 				cmd->execute_cmd =
1429 					target_emulate_set_target_port_groups;
1430 			}
1431 			*size = get_unaligned_be32(&cdb[6]);
1432 		} else {
1433 			/*
1434 			 * GPCMD_SEND_KEY from multi media commands
1435 			 */
1436 			*size = get_unaligned_be16(&cdb[8]);
1437 		}
1438 		break;
1439 	default:
1440 		return TCM_UNSUPPORTED_SCSI_OPCODE;
1441 	}
1442 
1443 	return 0;
1444 }
1445 EXPORT_SYMBOL(spc_parse_cdb);
1446