1/*
2 * SCSI Block Commands (SBC) parsing and emulation.
3 *
4 * (c) Copyright 2002-2013 Datera, Inc.
5 *
6 * Nicholas A. Bellinger <nab@kernel.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 */
22
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/ratelimit.h>
26#include <linux/crc-t10dif.h>
27#include <linux/t10-pi.h>
28#include <asm/unaligned.h>
29#include <scsi/scsi_proto.h>
30#include <scsi/scsi_tcq.h>
31
32#include <target/target_core_base.h>
33#include <target/target_core_backend.h>
34#include <target/target_core_fabric.h>
35
36#include "target_core_internal.h"
37#include "target_core_ua.h"
38#include "target_core_alua.h"
39
40static sense_reason_t
41sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
42static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
43
44static sense_reason_t
45sbc_emulate_readcapacity(struct se_cmd *cmd)
46{
47 struct se_device *dev = cmd->se_dev;
48 unsigned char *cdb = cmd->t_task_cdb;
49 unsigned long long blocks_long = dev->transport->get_blocks(dev);
50 unsigned char *rbuf;
51 unsigned char buf[8];
52 u32 blocks;
53
54 /*
55 * SBC-2 says:
56 * If the PMI bit is set to zero and the LOGICAL BLOCK
57 * ADDRESS field is not set to zero, the device server shall
58 * terminate the command with CHECK CONDITION status with
59 * the sense key set to ILLEGAL REQUEST and the additional
60 * sense code set to INVALID FIELD IN CDB.
61 *
62 * In SBC-3, these fields are obsolete, but some SCSI
63 * compliance tests actually check this, so we might as well
64 * follow SBC-2.
65 */
66 if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
67 return TCM_INVALID_CDB_FIELD;
68
69 if (blocks_long >= 0x00000000ffffffff)
70 blocks = 0xffffffff;
71 else
72 blocks = (u32)blocks_long;
73
74 put_unaligned_be32(blocks, &buf[0]);
75 put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
76
77 rbuf = transport_kmap_data_sg(cmd);
78 if (rbuf) {
79 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
80 transport_kunmap_data_sg(cmd);
81 }
82
83 target_complete_cmd_with_length(cmd, GOOD, 8);
84 return 0;
85}
86
87static sense_reason_t
88sbc_emulate_readcapacity_16(struct se_cmd *cmd)
89{
90 struct se_device *dev = cmd->se_dev;
91 struct se_session *sess = cmd->se_sess;
92 int pi_prot_type = dev->dev_attrib.pi_prot_type;
93
94 unsigned char *rbuf;
95 unsigned char buf[32];
96 unsigned long long blocks = dev->transport->get_blocks(dev);
97
98 memset(buf, 0, sizeof(buf));
99 put_unaligned_be64(blocks, &buf[0]);
100 put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
101 /*
102 * Set P_TYPE and PROT_EN bits for DIF support
103 */
104 if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
105 /*
106 * Only override a device's pi_prot_type if no T10-PI is
107 * available, and sess_prot_type has been explicitly enabled.
108 */
109 if (!pi_prot_type)
110 pi_prot_type = sess->sess_prot_type;
111
112 if (pi_prot_type)
113 buf[12] = (pi_prot_type - 1) << 1 | 0x1;
114 }
115
116 if (dev->transport->get_lbppbe)
117 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
118
119 if (dev->transport->get_alignment_offset_lbas) {
120 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
121
122 put_unaligned_be16(lalba, &buf[14]);
123 }
124
125 /*
126 * Set Thin Provisioning Enable bit following sbc3r22 in section
127 * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
128 */
129 if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
130 buf[14] |= 0x80;
131
132 /*
133 * LBPRZ signifies that zeroes will be read back from an LBA after
134 * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2)
135 */
136 if (dev->dev_attrib.unmap_zeroes_data)
137 buf[14] |= 0x40;
138 }
139
140 rbuf = transport_kmap_data_sg(cmd);
141 if (rbuf) {
142 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
143 transport_kunmap_data_sg(cmd);
144 }
145
146 target_complete_cmd_with_length(cmd, GOOD, 32);
147 return 0;
148}
149
150static sense_reason_t
151sbc_emulate_startstop(struct se_cmd *cmd)
152{
153 unsigned char *cdb = cmd->t_task_cdb;
154
155 /*
156 * See sbc3r36 section 5.25
157 * Immediate bit should be set since there is nothing to complete
158 * POWER CONDITION MODIFIER 0h
159 */
160 if (!(cdb[1] & 1) || cdb[2] || cdb[3])
161 return TCM_INVALID_CDB_FIELD;
162
163 /*
164 * See sbc3r36 section 5.25
165 * POWER CONDITION 0h START_VALID - process START and LOEJ
166 */
167 if (cdb[4] >> 4 & 0xf)
168 return TCM_INVALID_CDB_FIELD;
169
170 /*
171 * See sbc3r36 section 5.25
172 * LOEJ 0h - nothing to load or unload
173 * START 1h - we are ready
174 */
175 if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
176 return TCM_INVALID_CDB_FIELD;
177
178 target_complete_cmd(cmd, SAM_STAT_GOOD);
179 return 0;
180}
181
182sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
183{
184 u32 num_blocks;
185
186 if (cmd->t_task_cdb[0] == WRITE_SAME)
187 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
188 else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
189 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
190 else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
191 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
192
193 /*
194 * Use the explicit range when non zero is supplied, otherwise calculate
195 * the remaining range based on ->get_blocks() - starting LBA.
196 */
197 if (num_blocks)
198 return num_blocks;
199
200 return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
201 cmd->t_task_lba + 1;
202}
203EXPORT_SYMBOL(sbc_get_write_same_sectors);
204
205static sense_reason_t
206sbc_execute_write_same_unmap(struct se_cmd *cmd)
207{
208 struct sbc_ops *ops = cmd->protocol_data;
209 sector_t nolb = sbc_get_write_same_sectors(cmd);
210 sense_reason_t ret;
211
212 if (nolb) {
213 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
214 if (ret)
215 return ret;
216 }
217
218 target_complete_cmd(cmd, GOOD);
219 return 0;
220}
221
222static sense_reason_t
223sbc_emulate_noop(struct se_cmd *cmd)
224{
225 target_complete_cmd(cmd, GOOD);
226 return 0;
227}
228
229static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
230{
231 return cmd->se_dev->dev_attrib.block_size * sectors;
232}
233
234static inline u32 transport_get_sectors_6(unsigned char *cdb)
235{
236 /*
237 * Use 8-bit sector value. SBC-3 says:
238 *
239 * A TRANSFER LENGTH field set to zero specifies that 256
240 * logical blocks shall be written. Any other value
241 * specifies the number of logical blocks that shall be
242 * written.
243 */
244 return cdb[4] ? : 256;
245}
246
247static inline u32 transport_get_sectors_10(unsigned char *cdb)
248{
249 return get_unaligned_be16(&cdb[7]);
250}
251
252static inline u32 transport_get_sectors_12(unsigned char *cdb)
253{
254 return get_unaligned_be32(&cdb[6]);
255}
256
257static inline u32 transport_get_sectors_16(unsigned char *cdb)
258{
259 return get_unaligned_be32(&cdb[10]);
260}
261
262/*
263 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
264 */
265static inline u32 transport_get_sectors_32(unsigned char *cdb)
266{
267 return get_unaligned_be32(&cdb[28]);
268
269}
270
271static inline u32 transport_lba_21(unsigned char *cdb)
272{
273 return get_unaligned_be24(&cdb[1]) & 0x1fffff;
274}
275
276static inline u32 transport_lba_32(unsigned char *cdb)
277{
278 return get_unaligned_be32(&cdb[2]);
279}
280
281static inline unsigned long long transport_lba_64(unsigned char *cdb)
282{
283 return get_unaligned_be64(&cdb[2]);
284}
285
286/*
287 * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
288 */
289static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
290{
291 return get_unaligned_be64(&cdb[12]);
292}
293
294static sense_reason_t
295sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
296{
297 struct se_device *dev = cmd->se_dev;
298 sector_t end_lba = dev->transport->get_blocks(dev) + 1;
299 unsigned int sectors = sbc_get_write_same_sectors(cmd);
300 sense_reason_t ret;
301
302 if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
303 pr_err("WRITE_SAME PBDATA and LBDATA"
304 " bits not supported for Block Discard"
305 " Emulation\n");
306 return TCM_UNSUPPORTED_SCSI_OPCODE;
307 }
308 if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
309 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
310 sectors, cmd->se_dev->dev_attrib.max_write_same_len);
311 return TCM_INVALID_CDB_FIELD;
312 }
313 /*
314 * Sanity check for LBA wrap and request past end of device.
315 */
316 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
317 ((cmd->t_task_lba + sectors) > end_lba)) {
318 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
319 (unsigned long long)end_lba, cmd->t_task_lba, sectors);
320 return TCM_ADDRESS_OUT_OF_RANGE;
321 }
322
323 /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
324 if (flags[0] & 0x10) {
325 pr_warn("WRITE SAME with ANCHOR not supported\n");
326 return TCM_INVALID_CDB_FIELD;
327 }
328 /*
329 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
330 * translated into block discard requests within backend code.
331 */
332 if (flags[0] & 0x08) {
333 if (!ops->execute_unmap)
334 return TCM_UNSUPPORTED_SCSI_OPCODE;
335
336 if (!dev->dev_attrib.emulate_tpws) {
337 pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
338 " has emulate_tpws disabled\n");
339 return TCM_UNSUPPORTED_SCSI_OPCODE;
340 }
341 cmd->execute_cmd = sbc_execute_write_same_unmap;
342 return 0;
343 }
344 if (!ops->execute_write_same)
345 return TCM_UNSUPPORTED_SCSI_OPCODE;
346
347 ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
348 if (ret)
349 return ret;
350
351 cmd->execute_cmd = ops->execute_write_same;
352 return 0;
353}
354
355static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
356 int *post_ret)
357{
358 unsigned char *buf, *addr;
359 struct scatterlist *sg;
360 unsigned int offset;
361 sense_reason_t ret = TCM_NO_SENSE;
362 int i, count;
363
364 if (!success)
365 return 0;
366
367 /*
368 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
369 *
370 * 1) read the specified logical block(s);
371 * 2) transfer logical blocks from the data-out buffer;
372 * 3) XOR the logical blocks transferred from the data-out buffer with
373 * the logical blocks read, storing the resulting XOR data in a buffer;
374 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
375 * blocks transferred from the data-out buffer; and
376 * 5) transfer the resulting XOR data to the data-in buffer.
377 */
378 buf = kmalloc(cmd->data_length, GFP_KERNEL);
379 if (!buf) {
380 pr_err("Unable to allocate xor_callback buf\n");
381 return TCM_OUT_OF_RESOURCES;
382 }
383 /*
384 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
385 * into the locally allocated *buf
386 */
387 sg_copy_to_buffer(cmd->t_data_sg,
388 cmd->t_data_nents,
389 buf,
390 cmd->data_length);
391
392 /*
393 * Now perform the XOR against the BIDI read memory located at
394 * cmd->t_mem_bidi_list
395 */
396
397 offset = 0;
398 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
399 addr = kmap_atomic(sg_page(sg));
400 if (!addr) {
401 ret = TCM_OUT_OF_RESOURCES;
402 goto out;
403 }
404
405 for (i = 0; i < sg->length; i++)
406 *(addr + sg->offset + i) ^= *(buf + offset + i);
407
408 offset += sg->length;
409 kunmap_atomic(addr);
410 }
411
412out:
413 kfree(buf);
414 return ret;
415}
416
417static sense_reason_t
418sbc_execute_rw(struct se_cmd *cmd)
419{
420 struct sbc_ops *ops = cmd->protocol_data;
421
422 return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
423 cmd->data_direction);
424}
425
426static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
427 int *post_ret)
428{
429 struct se_device *dev = cmd->se_dev;
430 sense_reason_t ret = TCM_NO_SENSE;
431
432 spin_lock_irq(&cmd->t_state_lock);
433 if (success) {
434 *post_ret = 1;
435
436 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
437 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
438 }
439 spin_unlock_irq(&cmd->t_state_lock);
440
441 /*
442 * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
443 * before the original READ I/O submission.
444 */
445 up(&dev->caw_sem);
446
447 return ret;
448}
449
450static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
451 int *post_ret)
452{
453 struct se_device *dev = cmd->se_dev;
454 struct sg_table write_tbl = { };
455 struct scatterlist *write_sg, *sg;
456 unsigned char *buf = NULL, *addr;
457 struct sg_mapping_iter m;
458 unsigned int offset = 0, len;
459 unsigned int nlbas = cmd->t_task_nolb;
460 unsigned int block_size = dev->dev_attrib.block_size;
461 unsigned int compare_len = (nlbas * block_size);
462 sense_reason_t ret = TCM_NO_SENSE;
463 int rc, i;
464
465 /*
466 * Handle early failure in transport_generic_request_failure(),
467 * which will not have taken ->caw_sem yet..
468 */
469 if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
470 return TCM_NO_SENSE;
471 /*
472 * Handle special case for zero-length COMPARE_AND_WRITE
473 */
474 if (!cmd->data_length)
475 goto out;
476 /*
477 * Immediately exit + release dev->caw_sem if command has already
478 * been failed with a non-zero SCSI status.
479 */
480 if (cmd->scsi_status) {
481 pr_debug("compare_and_write_callback: non zero scsi_status:"
482 " 0x%02x\n", cmd->scsi_status);
483 *post_ret = 1;
484 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
485 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
486 goto out;
487 }
488
489 buf = kzalloc(cmd->data_length, GFP_KERNEL);
490 if (!buf) {
491 pr_err("Unable to allocate compare_and_write buf\n");
492 ret = TCM_OUT_OF_RESOURCES;
493 goto out;
494 }
495
496 if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) {
497 pr_err("Unable to allocate compare_and_write sg\n");
498 ret = TCM_OUT_OF_RESOURCES;
499 goto out;
500 }
501 write_sg = write_tbl.sgl;
502 /*
503 * Setup verify and write data payloads from total NumberLBAs.
504 */
505 rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
506 cmd->data_length);
507 if (!rc) {
508 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
509 ret = TCM_OUT_OF_RESOURCES;
510 goto out;
511 }
512 /*
513 * Compare against SCSI READ payload against verify payload
514 */
515 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
516 addr = (unsigned char *)kmap_atomic(sg_page(sg));
517 if (!addr) {
518 ret = TCM_OUT_OF_RESOURCES;
519 goto out;
520 }
521
522 len = min(sg->length, compare_len);
523
524 if (memcmp(addr, buf + offset, len)) {
525 pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
526 addr, buf + offset);
527 kunmap_atomic(addr);
528 goto miscompare;
529 }
530 kunmap_atomic(addr);
531
532 offset += len;
533 compare_len -= len;
534 if (!compare_len)
535 break;
536 }
537
538 i = 0;
539 len = cmd->t_task_nolb * block_size;
540 sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
541 /*
542 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
543 */
544 while (len) {
545 sg_miter_next(&m);
546
547 if (block_size < PAGE_SIZE) {
548 sg_set_page(&write_sg[i], m.page, block_size,
549 m.piter.sg->offset + block_size);
550 } else {
551 sg_miter_next(&m);
552 sg_set_page(&write_sg[i], m.page, block_size,
553 m.piter.sg->offset);
554 }
555 len -= block_size;
556 i++;
557 }
558 sg_miter_stop(&m);
559 /*
560 * Save the original SGL + nents values before updating to new
561 * assignments, to be released in transport_free_pages() ->
562 * transport_reset_sgl_orig()
563 */
564 cmd->t_data_sg_orig = cmd->t_data_sg;
565 cmd->t_data_sg = write_sg;
566 cmd->t_data_nents_orig = cmd->t_data_nents;
567 cmd->t_data_nents = 1;
568
569 cmd->sam_task_attr = TCM_HEAD_TAG;
570 cmd->transport_complete_callback = compare_and_write_post;
571 /*
572 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
573 * for submitting the adjusted SGL to write instance user-data.
574 */
575 cmd->execute_cmd = sbc_execute_rw;
576
577 spin_lock_irq(&cmd->t_state_lock);
578 cmd->t_state = TRANSPORT_PROCESSING;
579 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
580 spin_unlock_irq(&cmd->t_state_lock);
581
582 __target_execute_cmd(cmd, false);
583
584 kfree(buf);
585 return ret;
586
587miscompare:
588 pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
589 dev->transport->name);
590 ret = TCM_MISCOMPARE_VERIFY;
591out:
592 /*
593 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
594 * sbc_compare_and_write() before the original READ I/O submission.
595 */
596 up(&dev->caw_sem);
597 sg_free_table(&write_tbl);
598 kfree(buf);
599 return ret;
600}
601
602static sense_reason_t
603sbc_compare_and_write(struct se_cmd *cmd)
604{
605 struct sbc_ops *ops = cmd->protocol_data;
606 struct se_device *dev = cmd->se_dev;
607 sense_reason_t ret;
608 int rc;
609 /*
610 * Submit the READ first for COMPARE_AND_WRITE to perform the
611 * comparision using SGLs at cmd->t_bidi_data_sg..
612 */
613 rc = down_interruptible(&dev->caw_sem);
614 if (rc != 0) {
615 cmd->transport_complete_callback = NULL;
616 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
617 }
618 /*
619 * Reset cmd->data_length to individual block_size in order to not
620 * confuse backend drivers that depend on this value matching the
621 * size of the I/O being submitted.
622 */
623 cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
624
625 ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
626 DMA_FROM_DEVICE);
627 if (ret) {
628 cmd->transport_complete_callback = NULL;
629 up(&dev->caw_sem);
630 return ret;
631 }
632 /*
633 * Unlock of dev->caw_sem to occur in compare_and_write_callback()
634 * upon MISCOMPARE, or in compare_and_write_done() upon completion
635 * of WRITE instance user-data.
636 */
637 return TCM_NO_SENSE;
638}
639
640static int
641sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
642 bool is_write, struct se_cmd *cmd)
643{
644 if (is_write) {
645 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
646 protect ? TARGET_PROT_DOUT_PASS :
647 TARGET_PROT_DOUT_INSERT;
648 switch (protect) {
649 case 0x0:
650 case 0x3:
651 cmd->prot_checks = 0;
652 break;
653 case 0x1:
654 case 0x5:
655 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
656 if (prot_type == TARGET_DIF_TYPE1_PROT)
657 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
658 break;
659 case 0x2:
660 if (prot_type == TARGET_DIF_TYPE1_PROT)
661 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
662 break;
663 case 0x4:
664 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
665 break;
666 default:
667 pr_err("Unsupported protect field %d\n", protect);
668 return -EINVAL;
669 }
670 } else {
671 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
672 protect ? TARGET_PROT_DIN_PASS :
673 TARGET_PROT_DIN_STRIP;
674 switch (protect) {
675 case 0x0:
676 case 0x1:
677 case 0x5:
678 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
679 if (prot_type == TARGET_DIF_TYPE1_PROT)
680 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
681 break;
682 case 0x2:
683 if (prot_type == TARGET_DIF_TYPE1_PROT)
684 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
685 break;
686 case 0x3:
687 cmd->prot_checks = 0;
688 break;
689 case 0x4:
690 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
691 break;
692 default:
693 pr_err("Unsupported protect field %d\n", protect);
694 return -EINVAL;
695 }
696 }
697
698 return 0;
699}
700
701static sense_reason_t
702sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
703 u32 sectors, bool is_write)
704{
705 u8 protect = cdb[1] >> 5;
706 int sp_ops = cmd->se_sess->sup_prot_ops;
707 int pi_prot_type = dev->dev_attrib.pi_prot_type;
708 bool fabric_prot = false;
709
710 if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
711 if (unlikely(protect &&
712 !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
713 pr_err("CDB contains protect bit, but device + fabric does"
714 " not advertise PROTECT=1 feature bit\n");
715 return TCM_INVALID_CDB_FIELD;
716 }
717 if (cmd->prot_pto)
718 return TCM_NO_SENSE;
719 }
720
721 switch (dev->dev_attrib.pi_prot_type) {
722 case TARGET_DIF_TYPE3_PROT:
723 cmd->reftag_seed = 0xffffffff;
724 break;
725 case TARGET_DIF_TYPE2_PROT:
726 if (protect)
727 return TCM_INVALID_CDB_FIELD;
728
729 cmd->reftag_seed = cmd->t_task_lba;
730 break;
731 case TARGET_DIF_TYPE1_PROT:
732 cmd->reftag_seed = cmd->t_task_lba;
733 break;
734 case TARGET_DIF_TYPE0_PROT:
735 /*
736 * See if the fabric supports T10-PI, and the session has been
737 * configured to allow export PROTECT=1 feature bit with backend
738 * devices that don't support T10-PI.
739 */
740 fabric_prot = is_write ?
741 !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
742 !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
743
744 if (fabric_prot && cmd->se_sess->sess_prot_type) {
745 pi_prot_type = cmd->se_sess->sess_prot_type;
746 break;
747 }
748 if (!protect)
749 return TCM_NO_SENSE;
750 /* Fallthrough */
751 default:
752 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
753 "PROTECT: 0x%02x\n", cdb[0], protect);
754 return TCM_INVALID_CDB_FIELD;
755 }
756
757 if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
758 return TCM_INVALID_CDB_FIELD;
759
760 cmd->prot_type = pi_prot_type;
761 cmd->prot_length = dev->prot_length * sectors;
762
763 /**
764 * In case protection information exists over the wire
765 * we modify command data length to describe pure data.
766 * The actual transfer length is data length + protection
767 * length
768 **/
769 if (protect)
770 cmd->data_length = sectors * dev->dev_attrib.block_size;
771
772 pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
773 "prot_op=%d prot_checks=%d\n",
774 __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
775 cmd->prot_op, cmd->prot_checks);
776
777 return TCM_NO_SENSE;
778}
779
780static int
781sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
782{
783 if (cdb[1] & 0x10) {
784 /* see explanation in spc_emulate_modesense */
785 if (!target_check_fua(dev)) {
786 pr_err("Got CDB: 0x%02x with DPO bit set, but device"
787 " does not advertise support for DPO\n", cdb[0]);
788 return -EINVAL;
789 }
790 }
791 if (cdb[1] & 0x8) {
792 if (!target_check_fua(dev)) {
793 pr_err("Got CDB: 0x%02x with FUA bit set, but device"
794 " does not advertise support for FUA write\n",
795 cdb[0]);
796 return -EINVAL;
797 }
798 cmd->se_cmd_flags |= SCF_FUA;
799 }
800 return 0;
801}
802
803sense_reason_t
804sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
805{
806 struct se_device *dev = cmd->se_dev;
807 unsigned char *cdb = cmd->t_task_cdb;
808 unsigned int size;
809 u32 sectors = 0;
810 sense_reason_t ret;
811
812 cmd->protocol_data = ops;
813
814 switch (cdb[0]) {
815 case READ_6:
816 sectors = transport_get_sectors_6(cdb);
817 cmd->t_task_lba = transport_lba_21(cdb);
818 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
819 cmd->execute_cmd = sbc_execute_rw;
820 break;
821 case READ_10:
822 sectors = transport_get_sectors_10(cdb);
823 cmd->t_task_lba = transport_lba_32(cdb);
824
825 if (sbc_check_dpofua(dev, cmd, cdb))
826 return TCM_INVALID_CDB_FIELD;
827
828 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
829 if (ret)
830 return ret;
831
832 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
833 cmd->execute_cmd = sbc_execute_rw;
834 break;
835 case READ_12:
836 sectors = transport_get_sectors_12(cdb);
837 cmd->t_task_lba = transport_lba_32(cdb);
838
839 if (sbc_check_dpofua(dev, cmd, cdb))
840 return TCM_INVALID_CDB_FIELD;
841
842 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
843 if (ret)
844 return ret;
845
846 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
847 cmd->execute_cmd = sbc_execute_rw;
848 break;
849 case READ_16:
850 sectors = transport_get_sectors_16(cdb);
851 cmd->t_task_lba = transport_lba_64(cdb);
852
853 if (sbc_check_dpofua(dev, cmd, cdb))
854 return TCM_INVALID_CDB_FIELD;
855
856 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
857 if (ret)
858 return ret;
859
860 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
861 cmd->execute_cmd = sbc_execute_rw;
862 break;
863 case WRITE_6:
864 sectors = transport_get_sectors_6(cdb);
865 cmd->t_task_lba = transport_lba_21(cdb);
866 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
867 cmd->execute_cmd = sbc_execute_rw;
868 break;
869 case WRITE_10:
870 case WRITE_VERIFY:
871 sectors = transport_get_sectors_10(cdb);
872 cmd->t_task_lba = transport_lba_32(cdb);
873
874 if (sbc_check_dpofua(dev, cmd, cdb))
875 return TCM_INVALID_CDB_FIELD;
876
877 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
878 if (ret)
879 return ret;
880
881 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
882 cmd->execute_cmd = sbc_execute_rw;
883 break;
884 case WRITE_12:
885 sectors = transport_get_sectors_12(cdb);
886 cmd->t_task_lba = transport_lba_32(cdb);
887
888 if (sbc_check_dpofua(dev, cmd, cdb))
889 return TCM_INVALID_CDB_FIELD;
890
891 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
892 if (ret)
893 return ret;
894
895 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
896 cmd->execute_cmd = sbc_execute_rw;
897 break;
898 case WRITE_16:
899 case WRITE_VERIFY_16:
900 sectors = transport_get_sectors_16(cdb);
901 cmd->t_task_lba = transport_lba_64(cdb);
902
903 if (sbc_check_dpofua(dev, cmd, cdb))
904 return TCM_INVALID_CDB_FIELD;
905
906 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
907 if (ret)
908 return ret;
909
910 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
911 cmd->execute_cmd = sbc_execute_rw;
912 break;
913 case XDWRITEREAD_10:
914 if (cmd->data_direction != DMA_TO_DEVICE ||
915 !(cmd->se_cmd_flags & SCF_BIDI))
916 return TCM_INVALID_CDB_FIELD;
917 sectors = transport_get_sectors_10(cdb);
918
919 if (sbc_check_dpofua(dev, cmd, cdb))
920 return TCM_INVALID_CDB_FIELD;
921
922 cmd->t_task_lba = transport_lba_32(cdb);
923 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
924
925 /*
926 * Setup BIDI XOR callback to be run after I/O completion.
927 */
928 cmd->execute_cmd = sbc_execute_rw;
929 cmd->transport_complete_callback = &xdreadwrite_callback;
930 break;
931 case VARIABLE_LENGTH_CMD:
932 {
933 u16 service_action = get_unaligned_be16(&cdb[8]);
934 switch (service_action) {
935 case XDWRITEREAD_32:
936 sectors = transport_get_sectors_32(cdb);
937
938 if (sbc_check_dpofua(dev, cmd, cdb))
939 return TCM_INVALID_CDB_FIELD;
940 /*
941 * Use WRITE_32 and READ_32 opcodes for the emulated
942 * XDWRITE_READ_32 logic.
943 */
944 cmd->t_task_lba = transport_lba_64_ext(cdb);
945 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
946
947 /*
948 * Setup BIDI XOR callback to be run during after I/O
949 * completion.
950 */
951 cmd->execute_cmd = sbc_execute_rw;
952 cmd->transport_complete_callback = &xdreadwrite_callback;
953 break;
954 case WRITE_SAME_32:
955 sectors = transport_get_sectors_32(cdb);
956 if (!sectors) {
957 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
958 " supported\n");
959 return TCM_INVALID_CDB_FIELD;
960 }
961
962 size = sbc_get_size(cmd, 1);
963 cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
964
965 ret = sbc_setup_write_same(cmd, &cdb[10], ops);
966 if (ret)
967 return ret;
968 break;
969 default:
970 pr_err("VARIABLE_LENGTH_CMD service action"
971 " 0x%04x not supported\n", service_action);
972 return TCM_UNSUPPORTED_SCSI_OPCODE;
973 }
974 break;
975 }
976 case COMPARE_AND_WRITE:
977 if (!dev->dev_attrib.emulate_caw) {
978 pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
979 dev->se_hba->backend->ops->name,
980 config_item_name(&dev->dev_group.cg_item),
981 dev->t10_wwn.unit_serial);
982 return TCM_UNSUPPORTED_SCSI_OPCODE;
983 }
984 sectors = cdb[13];
985 /*
986 * Currently enforce COMPARE_AND_WRITE for a single sector
987 */
988 if (sectors > 1) {
989 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
990 " than 1\n", sectors);
991 return TCM_INVALID_CDB_FIELD;
992 }
993 if (sbc_check_dpofua(dev, cmd, cdb))
994 return TCM_INVALID_CDB_FIELD;
995
996 /*
997 * Double size because we have two buffers, note that
998 * zero is not an error..
999 */
1000 size = 2 * sbc_get_size(cmd, sectors);
1001 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1002 cmd->t_task_nolb = sectors;
1003 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1004 cmd->execute_cmd = sbc_compare_and_write;
1005 cmd->transport_complete_callback = compare_and_write_callback;
1006 break;
1007 case READ_CAPACITY:
1008 size = READ_CAP_LEN;
1009 cmd->execute_cmd = sbc_emulate_readcapacity;
1010 break;
1011 case SERVICE_ACTION_IN_16:
1012 switch (cmd->t_task_cdb[1] & 0x1f) {
1013 case SAI_READ_CAPACITY_16:
1014 cmd->execute_cmd = sbc_emulate_readcapacity_16;
1015 break;
1016 case SAI_REPORT_REFERRALS:
1017 cmd->execute_cmd = target_emulate_report_referrals;
1018 break;
1019 default:
1020 pr_err("Unsupported SA: 0x%02x\n",
1021 cmd->t_task_cdb[1] & 0x1f);
1022 return TCM_INVALID_CDB_FIELD;
1023 }
1024 size = get_unaligned_be32(&cdb[10]);
1025 break;
1026 case SYNCHRONIZE_CACHE:
1027 case SYNCHRONIZE_CACHE_16:
1028 if (cdb[0] == SYNCHRONIZE_CACHE) {
1029 sectors = transport_get_sectors_10(cdb);
1030 cmd->t_task_lba = transport_lba_32(cdb);
1031 } else {
1032 sectors = transport_get_sectors_16(cdb);
1033 cmd->t_task_lba = transport_lba_64(cdb);
1034 }
1035 if (ops->execute_sync_cache) {
1036 cmd->execute_cmd = ops->execute_sync_cache;
1037 goto check_lba;
1038 }
1039 size = 0;
1040 cmd->execute_cmd = sbc_emulate_noop;
1041 break;
1042 case UNMAP:
1043 if (!ops->execute_unmap)
1044 return TCM_UNSUPPORTED_SCSI_OPCODE;
1045
1046 if (!dev->dev_attrib.emulate_tpu) {
1047 pr_err("Got UNMAP, but backend device has"
1048 " emulate_tpu disabled\n");
1049 return TCM_UNSUPPORTED_SCSI_OPCODE;
1050 }
1051 size = get_unaligned_be16(&cdb[7]);
1052 cmd->execute_cmd = sbc_execute_unmap;
1053 break;
1054 case WRITE_SAME_16:
1055 sectors = transport_get_sectors_16(cdb);
1056 if (!sectors) {
1057 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1058 return TCM_INVALID_CDB_FIELD;
1059 }
1060
1061 size = sbc_get_size(cmd, 1);
1062 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1063
1064 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1065 if (ret)
1066 return ret;
1067 break;
1068 case WRITE_SAME:
1069 sectors = transport_get_sectors_10(cdb);
1070 if (!sectors) {
1071 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1072 return TCM_INVALID_CDB_FIELD;
1073 }
1074
1075 size = sbc_get_size(cmd, 1);
1076 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1077
1078 /*
1079 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1080 * of byte 1 bit 3 UNMAP instead of original reserved field
1081 */
1082 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1083 if (ret)
1084 return ret;
1085 break;
1086 case VERIFY:
1087 case VERIFY_16:
1088 size = 0;
1089 if (cdb[0] == VERIFY) {
1090 sectors = transport_get_sectors_10(cdb);
1091 cmd->t_task_lba = transport_lba_32(cdb);
1092 } else {
1093 sectors = transport_get_sectors_16(cdb);
1094 cmd->t_task_lba = transport_lba_64(cdb);
1095 }
1096 cmd->execute_cmd = sbc_emulate_noop;
1097 goto check_lba;
1098 case REZERO_UNIT:
1099 case SEEK_6:
1100 case SEEK_10:
1101 /*
1102 * There are still clients out there which use these old SCSI-2
1103 * commands. This mainly happens when running VMs with legacy
1104 * guest systems, connected via SCSI command pass-through to
1105 * iSCSI targets. Make them happy and return status GOOD.
1106 */
1107 size = 0;
1108 cmd->execute_cmd = sbc_emulate_noop;
1109 break;
1110 case START_STOP:
1111 size = 0;
1112 cmd->execute_cmd = sbc_emulate_startstop;
1113 break;
1114 default:
1115 ret = spc_parse_cdb(cmd, &size);
1116 if (ret)
1117 return ret;
1118 }
1119
1120 /* reject any command that we don't have a handler for */
1121 if (!cmd->execute_cmd)
1122 return TCM_UNSUPPORTED_SCSI_OPCODE;
1123
1124 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1125 unsigned long long end_lba;
1126check_lba:
1127 end_lba = dev->transport->get_blocks(dev) + 1;
1128 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1129 ((cmd->t_task_lba + sectors) > end_lba)) {
1130 pr_err("cmd exceeds last lba %llu "
1131 "(lba %llu, sectors %u)\n",
1132 end_lba, cmd->t_task_lba, sectors);
1133 return TCM_ADDRESS_OUT_OF_RANGE;
1134 }
1135
1136 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1137 size = sbc_get_size(cmd, sectors);
1138 }
1139
1140 return target_cmd_size_check(cmd, size);
1141}
1142EXPORT_SYMBOL(sbc_parse_cdb);
1143
1144u32 sbc_get_device_type(struct se_device *dev)
1145{
1146 return TYPE_DISK;
1147}
1148EXPORT_SYMBOL(sbc_get_device_type);
1149
1150static sense_reason_t
1151sbc_execute_unmap(struct se_cmd *cmd)
1152{
1153 struct sbc_ops *ops = cmd->protocol_data;
1154 struct se_device *dev = cmd->se_dev;
1155 unsigned char *buf, *ptr = NULL;
1156 sector_t lba;
1157 int size;
1158 u32 range;
1159 sense_reason_t ret = 0;
1160 int dl, bd_dl;
1161
1162 /* We never set ANC_SUP */
1163 if (cmd->t_task_cdb[1])
1164 return TCM_INVALID_CDB_FIELD;
1165
1166 if (cmd->data_length == 0) {
1167 target_complete_cmd(cmd, SAM_STAT_GOOD);
1168 return 0;
1169 }
1170
1171 if (cmd->data_length < 8) {
1172 pr_warn("UNMAP parameter list length %u too small\n",
1173 cmd->data_length);
1174 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1175 }
1176
1177 buf = transport_kmap_data_sg(cmd);
1178 if (!buf)
1179 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1180
1181 dl = get_unaligned_be16(&buf[0]);
1182 bd_dl = get_unaligned_be16(&buf[2]);
1183
1184 size = cmd->data_length - 8;
1185 if (bd_dl > size)
1186 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1187 cmd->data_length, bd_dl);
1188 else
1189 size = bd_dl;
1190
1191 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1192 ret = TCM_INVALID_PARAMETER_LIST;
1193 goto err;
1194 }
1195
1196 /* First UNMAP block descriptor starts at 8 byte offset */
1197 ptr = &buf[8];
1198 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1199 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1200
1201 while (size >= 16) {
1202 lba = get_unaligned_be64(&ptr[0]);
1203 range = get_unaligned_be32(&ptr[8]);
1204 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1205 (unsigned long long)lba, range);
1206
1207 if (range > dev->dev_attrib.max_unmap_lba_count) {
1208 ret = TCM_INVALID_PARAMETER_LIST;
1209 goto err;
1210 }
1211
1212 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1213 ret = TCM_ADDRESS_OUT_OF_RANGE;
1214 goto err;
1215 }
1216
1217 if (range) {
1218 ret = ops->execute_unmap(cmd, lba, range);
1219 if (ret)
1220 goto err;
1221 }
1222
1223 ptr += 16;
1224 size -= 16;
1225 }
1226
1227err:
1228 transport_kunmap_data_sg(cmd);
1229 if (!ret)
1230 target_complete_cmd(cmd, GOOD);
1231 return ret;
1232}
1233
1234void
1235sbc_dif_generate(struct se_cmd *cmd)
1236{
1237 struct se_device *dev = cmd->se_dev;
1238 struct t10_pi_tuple *sdt;
1239 struct scatterlist *dsg = cmd->t_data_sg, *psg;
1240 sector_t sector = cmd->t_task_lba;
1241 void *daddr, *paddr;
1242 int i, j, offset = 0;
1243 unsigned int block_size = dev->dev_attrib.block_size;
1244
1245 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1246 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1247 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1248
1249 for (j = 0; j < psg->length;
1250 j += sizeof(*sdt)) {
1251 __u16 crc;
1252 unsigned int avail;
1253
1254 if (offset >= dsg->length) {
1255 offset -= dsg->length;
1256 kunmap_atomic(daddr - dsg->offset);
1257 dsg = sg_next(dsg);
1258 if (!dsg) {
1259 kunmap_atomic(paddr - psg->offset);
1260 return;
1261 }
1262 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1263 }
1264
1265 sdt = paddr + j;
1266 avail = min(block_size, dsg->length - offset);
1267 crc = crc_t10dif(daddr + offset, avail);
1268 if (avail < block_size) {
1269 kunmap_atomic(daddr - dsg->offset);
1270 dsg = sg_next(dsg);
1271 if (!dsg) {
1272 kunmap_atomic(paddr - psg->offset);
1273 return;
1274 }
1275 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1276 offset = block_size - avail;
1277 crc = crc_t10dif_update(crc, daddr, offset);
1278 } else {
1279 offset += block_size;
1280 }
1281
1282 sdt->guard_tag = cpu_to_be16(crc);
1283 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1284 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1285 sdt->app_tag = 0;
1286
1287 pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1288 " app_tag: 0x%04x ref_tag: %u\n",
1289 (cmd->data_direction == DMA_TO_DEVICE) ?
1290 "WRITE" : "READ", (unsigned long long)sector,
1291 sdt->guard_tag, sdt->app_tag,
1292 be32_to_cpu(sdt->ref_tag));
1293
1294 sector++;
1295 }
1296
1297 kunmap_atomic(daddr - dsg->offset);
1298 kunmap_atomic(paddr - psg->offset);
1299 }
1300}
1301
1302static sense_reason_t
1303sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1304 __u16 crc, sector_t sector, unsigned int ei_lba)
1305{
1306 __be16 csum;
1307
1308 if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1309 goto check_ref;
1310
1311 csum = cpu_to_be16(crc);
1312
1313 if (sdt->guard_tag != csum) {
1314 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1315 " csum 0x%04x\n", (unsigned long long)sector,
1316 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1317 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1318 }
1319
1320check_ref:
1321 if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1322 return 0;
1323
1324 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1325 be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1326 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1327 " sector MSB: 0x%08x\n", (unsigned long long)sector,
1328 be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1329 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1330 }
1331
1332 if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1333 be32_to_cpu(sdt->ref_tag) != ei_lba) {
1334 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1335 " ei_lba: 0x%08x\n", (unsigned long long)sector,
1336 be32_to_cpu(sdt->ref_tag), ei_lba);
1337 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1338 }
1339
1340 return 0;
1341}
1342
1343void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1344 struct scatterlist *sg, int sg_off)
1345{
1346 struct se_device *dev = cmd->se_dev;
1347 struct scatterlist *psg;
1348 void *paddr, *addr;
1349 unsigned int i, len, left;
1350 unsigned int offset = sg_off;
1351
1352 if (!sg)
1353 return;
1354
1355 left = sectors * dev->prot_length;
1356
1357 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1358 unsigned int psg_len, copied = 0;
1359
1360 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1361 psg_len = min(left, psg->length);
1362 while (psg_len) {
1363 len = min(psg_len, sg->length - offset);
1364 addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1365
1366 if (read)
1367 memcpy(paddr + copied, addr, len);
1368 else
1369 memcpy(addr, paddr + copied, len);
1370
1371 left -= len;
1372 offset += len;
1373 copied += len;
1374 psg_len -= len;
1375
1376 kunmap_atomic(addr - sg->offset - offset);
1377
1378 if (offset >= sg->length) {
1379 sg = sg_next(sg);
1380 offset = 0;
1381 }
1382 }
1383 kunmap_atomic(paddr - psg->offset);
1384 }
1385}
1386EXPORT_SYMBOL(sbc_dif_copy_prot);
1387
1388sense_reason_t
1389sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1390 unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1391{
1392 struct se_device *dev = cmd->se_dev;
1393 struct t10_pi_tuple *sdt;
1394 struct scatterlist *dsg = cmd->t_data_sg;
1395 sector_t sector = start;
1396 void *daddr, *paddr;
1397 int i;
1398 sense_reason_t rc;
1399 int dsg_off = 0;
1400 unsigned int block_size = dev->dev_attrib.block_size;
1401
1402 for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1403 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1404 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1405
1406 for (i = psg_off; i < psg->length &&
1407 sector < start + sectors;
1408 i += sizeof(*sdt)) {
1409 __u16 crc;
1410 unsigned int avail;
1411
1412 if (dsg_off >= dsg->length) {
1413 dsg_off -= dsg->length;
1414 kunmap_atomic(daddr - dsg->offset);
1415 dsg = sg_next(dsg);
1416 if (!dsg) {
1417 kunmap_atomic(paddr - psg->offset);
1418 return 0;
1419 }
1420 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1421 }
1422
1423 sdt = paddr + i;
1424
1425 pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1426 " app_tag: 0x%04x ref_tag: %u\n",
1427 (unsigned long long)sector, sdt->guard_tag,
1428 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1429
1430 if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1431 dsg_off += block_size;
1432 goto next;
1433 }
1434
1435 avail = min(block_size, dsg->length - dsg_off);
1436 crc = crc_t10dif(daddr + dsg_off, avail);
1437 if (avail < block_size) {
1438 kunmap_atomic(daddr - dsg->offset);
1439 dsg = sg_next(dsg);
1440 if (!dsg) {
1441 kunmap_atomic(paddr - psg->offset);
1442 return 0;
1443 }
1444 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1445 dsg_off = block_size - avail;
1446 crc = crc_t10dif_update(crc, daddr, dsg_off);
1447 } else {
1448 dsg_off += block_size;
1449 }
1450
1451 rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1452 if (rc) {
1453 kunmap_atomic(daddr - dsg->offset);
1454 kunmap_atomic(paddr - psg->offset);
1455 cmd->bad_sector = sector;
1456 return rc;
1457 }
1458next:
1459 sector++;
1460 ei_lba++;
1461 }
1462
1463 psg_off = 0;
1464 kunmap_atomic(daddr - dsg->offset);
1465 kunmap_atomic(paddr - psg->offset);
1466 }
1467
1468 return 0;
1469}
1470EXPORT_SYMBOL(sbc_dif_verify);
1471