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