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