LiteX: driver for MMCM
[linux/fpc-iii.git] / drivers / target / target_core_sbc.c
blobf7c527a826fdeb32b8bb80943e41d0b135eca19c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * SCSI Block Commands (SBC) parsing and emulation.
5 * (c) Copyright 2002-2013 Datera, Inc.
7 * Nicholas A. Bellinger <nab@kernel.org>
8 */
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>
19 #include <target/target_core_base.h>
20 #include <target/target_core_backend.h>
21 #include <target/target_core_fabric.h>
23 #include "target_core_internal.h"
24 #include "target_core_ua.h"
25 #include "target_core_alua.h"
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);
31 static sense_reason_t
32 sbc_emulate_readcapacity(struct se_cmd *cmd)
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;
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.
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.
53 if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
54 return TCM_INVALID_CDB_FIELD;
56 if (blocks_long >= 0x00000000ffffffff)
57 blocks = 0xffffffff;
58 else
59 blocks = (u32)blocks_long;
61 put_unaligned_be32(blocks, &buf[0]);
62 put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
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);
70 target_complete_cmd_with_length(cmd, GOOD, 8);
71 return 0;
74 static sense_reason_t
75 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
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;
81 unsigned char *rbuf;
82 unsigned char buf[32];
83 unsigned long long blocks = dev->transport->get_blocks(dev);
85 memset(buf, 0, sizeof(buf));
86 put_unaligned_be64(blocks, &buf[0]);
87 put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
89 * Set P_TYPE and PROT_EN bits for DIF support
91 if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
93 * Only override a device's pi_prot_type if no T10-PI is
94 * available, and sess_prot_type has been explicitly enabled.
96 if (!pi_prot_type)
97 pi_prot_type = sess->sess_prot_type;
99 if (pi_prot_type)
100 buf[12] = (pi_prot_type - 1) << 1 | 0x1;
103 if (dev->transport->get_lbppbe)
104 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
106 if (dev->transport->get_alignment_offset_lbas) {
107 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
109 put_unaligned_be16(lalba, &buf[14]);
113 * Set Thin Provisioning Enable bit following sbc3r22 in section
114 * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
116 if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
117 buf[14] |= 0x80;
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)
123 if (dev->dev_attrib.unmap_zeroes_data)
124 buf[14] |= 0x40;
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);
133 target_complete_cmd_with_length(cmd, GOOD, 32);
134 return 0;
137 static sense_reason_t
138 sbc_emulate_startstop(struct se_cmd *cmd)
140 unsigned char *cdb = cmd->t_task_cdb;
143 * See sbc3r36 section 5.25
144 * Immediate bit should be set since there is nothing to complete
145 * POWER CONDITION MODIFIER 0h
147 if (!(cdb[1] & 1) || cdb[2] || cdb[3])
148 return TCM_INVALID_CDB_FIELD;
151 * See sbc3r36 section 5.25
152 * POWER CONDITION 0h START_VALID - process START and LOEJ
154 if (cdb[4] >> 4 & 0xf)
155 return TCM_INVALID_CDB_FIELD;
158 * See sbc3r36 section 5.25
159 * LOEJ 0h - nothing to load or unload
160 * START 1h - we are ready
162 if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
163 return TCM_INVALID_CDB_FIELD;
165 target_complete_cmd(cmd, SAM_STAT_GOOD);
166 return 0;
169 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
171 u32 num_blocks;
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]);
181 * Use the explicit range when non zero is supplied, otherwise calculate
182 * the remaining range based on ->get_blocks() - starting LBA.
184 if (num_blocks)
185 return num_blocks;
187 return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
188 cmd->t_task_lba + 1;
190 EXPORT_SYMBOL(sbc_get_write_same_sectors);
192 static sense_reason_t
193 sbc_execute_write_same_unmap(struct se_cmd *cmd)
195 struct sbc_ops *ops = cmd->protocol_data;
196 sector_t nolb = sbc_get_write_same_sectors(cmd);
197 sense_reason_t ret;
199 if (nolb) {
200 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
201 if (ret)
202 return ret;
205 target_complete_cmd(cmd, GOOD);
206 return 0;
209 static sense_reason_t
210 sbc_emulate_noop(struct se_cmd *cmd)
212 target_complete_cmd(cmd, GOOD);
213 return 0;
216 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
218 return cmd->se_dev->dev_attrib.block_size * sectors;
221 static inline u32 transport_get_sectors_6(unsigned char *cdb)
224 * Use 8-bit sector value. SBC-3 says:
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.
231 return cdb[4] ? : 256;
234 static inline u32 transport_get_sectors_10(unsigned char *cdb)
236 return get_unaligned_be16(&cdb[7]);
239 static inline u32 transport_get_sectors_12(unsigned char *cdb)
241 return get_unaligned_be32(&cdb[6]);
244 static inline u32 transport_get_sectors_16(unsigned char *cdb)
246 return get_unaligned_be32(&cdb[10]);
250 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
252 static inline u32 transport_get_sectors_32(unsigned char *cdb)
254 return get_unaligned_be32(&cdb[28]);
258 static inline u32 transport_lba_21(unsigned char *cdb)
260 return get_unaligned_be24(&cdb[1]) & 0x1fffff;
263 static inline u32 transport_lba_32(unsigned char *cdb)
265 return get_unaligned_be32(&cdb[2]);
268 static inline unsigned long long transport_lba_64(unsigned char *cdb)
270 return get_unaligned_be64(&cdb[2]);
274 * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
276 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
278 return get_unaligned_be64(&cdb[12]);
281 static sense_reason_t
282 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
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;
289 if ((flags[0] & 0x04) || (flags[0] & 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;
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;
301 * Sanity check for LBA wrap and request past end of device.
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;
310 /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
311 if (flags[0] & 0x10) {
312 pr_warn("WRITE SAME with ANCHOR not supported\n");
313 return TCM_INVALID_CDB_FIELD;
316 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
317 * translated into block discard requests within backend code.
319 if (flags[0] & 0x08) {
320 if (!ops->execute_unmap)
321 return TCM_UNSUPPORTED_SCSI_OPCODE;
323 if (!dev->dev_attrib.emulate_tpws) {
324 pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
325 " has emulate_tpws disabled\n");
326 return TCM_UNSUPPORTED_SCSI_OPCODE;
328 cmd->execute_cmd = sbc_execute_write_same_unmap;
329 return 0;
331 if (!ops->execute_write_same)
332 return TCM_UNSUPPORTED_SCSI_OPCODE;
334 ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
335 if (ret)
336 return ret;
338 cmd->execute_cmd = ops->execute_write_same;
339 return 0;
342 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
343 int *post_ret)
345 unsigned char *buf, *addr;
346 struct scatterlist *sg;
347 unsigned int offset;
348 sense_reason_t ret = TCM_NO_SENSE;
349 int i, count;
351 if (!success)
352 return 0;
355 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
357 * 1) read the specified logical block(s);
358 * 2) transfer logical blocks from the data-out buffer;
359 * 3) XOR the logical blocks transferred from the data-out buffer with
360 * the logical blocks read, storing the resulting XOR data in a buffer;
361 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
362 * blocks transferred from the data-out buffer; and
363 * 5) transfer the resulting XOR data to the data-in buffer.
365 buf = kmalloc(cmd->data_length, GFP_KERNEL);
366 if (!buf) {
367 pr_err("Unable to allocate xor_callback buf\n");
368 return TCM_OUT_OF_RESOURCES;
371 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
372 * into the locally allocated *buf
374 sg_copy_to_buffer(cmd->t_data_sg,
375 cmd->t_data_nents,
376 buf,
377 cmd->data_length);
380 * Now perform the XOR against the BIDI read memory located at
381 * cmd->t_mem_bidi_list
384 offset = 0;
385 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
386 addr = kmap_atomic(sg_page(sg));
387 if (!addr) {
388 ret = TCM_OUT_OF_RESOURCES;
389 goto out;
392 for (i = 0; i < sg->length; i++)
393 *(addr + sg->offset + i) ^= *(buf + offset + i);
395 offset += sg->length;
396 kunmap_atomic(addr);
399 out:
400 kfree(buf);
401 return ret;
404 static sense_reason_t
405 sbc_execute_rw(struct se_cmd *cmd)
407 struct sbc_ops *ops = cmd->protocol_data;
409 return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
410 cmd->data_direction);
413 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
414 int *post_ret)
416 struct se_device *dev = cmd->se_dev;
417 sense_reason_t ret = TCM_NO_SENSE;
419 spin_lock_irq(&cmd->t_state_lock);
420 if (success) {
421 *post_ret = 1;
423 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
424 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
426 spin_unlock_irq(&cmd->t_state_lock);
429 * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
430 * before the original READ I/O submission.
432 up(&dev->caw_sem);
434 return ret;
438 * compare @cmp_len bytes of @read_sgl with @cmp_sgl. On miscompare, fill
439 * @miscmp_off and return TCM_MISCOMPARE_VERIFY.
441 static sense_reason_t
442 compare_and_write_do_cmp(struct scatterlist *read_sgl, unsigned int read_nents,
443 struct scatterlist *cmp_sgl, unsigned int cmp_nents,
444 unsigned int cmp_len, unsigned int *miscmp_off)
446 unsigned char *buf = NULL;
447 struct scatterlist *sg;
448 sense_reason_t ret;
449 unsigned int offset;
450 size_t rc;
451 int i;
453 buf = kzalloc(cmp_len, GFP_KERNEL);
454 if (!buf) {
455 ret = TCM_OUT_OF_RESOURCES;
456 goto out;
459 rc = sg_copy_to_buffer(cmp_sgl, cmp_nents, buf, cmp_len);
460 if (!rc) {
461 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
462 ret = TCM_OUT_OF_RESOURCES;
463 goto out;
466 * Compare SCSI READ payload against verify payload
468 offset = 0;
469 ret = TCM_NO_SENSE;
470 for_each_sg(read_sgl, sg, read_nents, i) {
471 unsigned int len = min(sg->length, cmp_len);
472 unsigned char *addr = kmap_atomic(sg_page(sg));
474 if (memcmp(addr, buf + offset, len)) {
475 unsigned int i;
477 for (i = 0; i < len && addr[i] == buf[offset + i]; i++)
479 *miscmp_off = offset + i;
480 pr_warn("Detected MISCOMPARE at offset %u\n",
481 *miscmp_off);
482 ret = TCM_MISCOMPARE_VERIFY;
484 kunmap_atomic(addr);
485 if (ret != TCM_NO_SENSE)
486 goto out;
488 offset += len;
489 cmp_len -= len;
490 if (!cmp_len)
491 break;
493 pr_debug("COMPARE AND WRITE read data matches compare data\n");
494 out:
495 kfree(buf);
496 return ret;
499 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
500 int *post_ret)
502 struct se_device *dev = cmd->se_dev;
503 struct sg_table write_tbl = { };
504 struct scatterlist *write_sg;
505 struct sg_mapping_iter m;
506 unsigned int len;
507 unsigned int block_size = dev->dev_attrib.block_size;
508 unsigned int compare_len = (cmd->t_task_nolb * block_size);
509 unsigned int miscmp_off = 0;
510 sense_reason_t ret = TCM_NO_SENSE;
511 int i;
514 * Handle early failure in transport_generic_request_failure(),
515 * which will not have taken ->caw_sem yet..
517 if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
518 return TCM_NO_SENSE;
520 * Handle special case for zero-length COMPARE_AND_WRITE
522 if (!cmd->data_length)
523 goto out;
525 * Immediately exit + release dev->caw_sem if command has already
526 * been failed with a non-zero SCSI status.
528 if (cmd->scsi_status) {
529 pr_debug("compare_and_write_callback: non zero scsi_status:"
530 " 0x%02x\n", cmd->scsi_status);
531 *post_ret = 1;
532 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
533 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
534 goto out;
537 ret = compare_and_write_do_cmp(cmd->t_bidi_data_sg,
538 cmd->t_bidi_data_nents,
539 cmd->t_data_sg,
540 cmd->t_data_nents,
541 compare_len,
542 &miscmp_off);
543 if (ret == TCM_MISCOMPARE_VERIFY) {
545 * SBC-4 r15: 5.3 COMPARE AND WRITE command
546 * In the sense data (see 4.18 and SPC-5) the offset from the
547 * start of the Data-Out Buffer to the first byte of data that
548 * was not equal shall be reported in the INFORMATION field.
550 cmd->sense_info = miscmp_off;
551 goto out;
552 } else if (ret)
553 goto out;
555 if (sg_alloc_table(&write_tbl, cmd->t_data_nents, GFP_KERNEL) < 0) {
556 pr_err("Unable to allocate compare_and_write sg\n");
557 ret = TCM_OUT_OF_RESOURCES;
558 goto out;
560 write_sg = write_tbl.sgl;
562 i = 0;
563 len = compare_len;
564 sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
566 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
568 while (len) {
569 sg_miter_next(&m);
571 if (block_size < PAGE_SIZE) {
572 sg_set_page(&write_sg[i], m.page, block_size,
573 m.piter.sg->offset + block_size);
574 } else {
575 sg_miter_next(&m);
576 sg_set_page(&write_sg[i], m.page, block_size,
577 m.piter.sg->offset);
579 len -= block_size;
580 i++;
582 sg_miter_stop(&m);
584 * Save the original SGL + nents values before updating to new
585 * assignments, to be released in transport_free_pages() ->
586 * transport_reset_sgl_orig()
588 cmd->t_data_sg_orig = cmd->t_data_sg;
589 cmd->t_data_sg = write_sg;
590 cmd->t_data_nents_orig = cmd->t_data_nents;
591 cmd->t_data_nents = 1;
593 cmd->sam_task_attr = TCM_HEAD_TAG;
594 cmd->transport_complete_callback = compare_and_write_post;
596 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
597 * for submitting the adjusted SGL to write instance user-data.
599 cmd->execute_cmd = sbc_execute_rw;
601 spin_lock_irq(&cmd->t_state_lock);
602 cmd->t_state = TRANSPORT_PROCESSING;
603 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
604 spin_unlock_irq(&cmd->t_state_lock);
606 __target_execute_cmd(cmd, false);
608 return ret;
610 out:
612 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
613 * sbc_compare_and_write() before the original READ I/O submission.
615 up(&dev->caw_sem);
616 sg_free_table(&write_tbl);
617 return ret;
620 static sense_reason_t
621 sbc_compare_and_write(struct se_cmd *cmd)
623 struct sbc_ops *ops = cmd->protocol_data;
624 struct se_device *dev = cmd->se_dev;
625 sense_reason_t ret;
626 int rc;
628 * Submit the READ first for COMPARE_AND_WRITE to perform the
629 * comparision using SGLs at cmd->t_bidi_data_sg..
631 rc = down_interruptible(&dev->caw_sem);
632 if (rc != 0) {
633 cmd->transport_complete_callback = NULL;
634 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
637 * Reset cmd->data_length to individual block_size in order to not
638 * confuse backend drivers that depend on this value matching the
639 * size of the I/O being submitted.
641 cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
643 ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
644 DMA_FROM_DEVICE);
645 if (ret) {
646 cmd->transport_complete_callback = NULL;
647 up(&dev->caw_sem);
648 return ret;
651 * Unlock of dev->caw_sem to occur in compare_and_write_callback()
652 * upon MISCOMPARE, or in compare_and_write_done() upon completion
653 * of WRITE instance user-data.
655 return TCM_NO_SENSE;
658 static int
659 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
660 bool is_write, struct se_cmd *cmd)
662 if (is_write) {
663 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
664 protect ? TARGET_PROT_DOUT_PASS :
665 TARGET_PROT_DOUT_INSERT;
666 switch (protect) {
667 case 0x0:
668 case 0x3:
669 cmd->prot_checks = 0;
670 break;
671 case 0x1:
672 case 0x5:
673 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
674 if (prot_type == TARGET_DIF_TYPE1_PROT)
675 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
676 break;
677 case 0x2:
678 if (prot_type == TARGET_DIF_TYPE1_PROT)
679 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
680 break;
681 case 0x4:
682 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
683 break;
684 default:
685 pr_err("Unsupported protect field %d\n", protect);
686 return -EINVAL;
688 } else {
689 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
690 protect ? TARGET_PROT_DIN_PASS :
691 TARGET_PROT_DIN_STRIP;
692 switch (protect) {
693 case 0x0:
694 case 0x1:
695 case 0x5:
696 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
697 if (prot_type == TARGET_DIF_TYPE1_PROT)
698 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
699 break;
700 case 0x2:
701 if (prot_type == TARGET_DIF_TYPE1_PROT)
702 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
703 break;
704 case 0x3:
705 cmd->prot_checks = 0;
706 break;
707 case 0x4:
708 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
709 break;
710 default:
711 pr_err("Unsupported protect field %d\n", protect);
712 return -EINVAL;
716 return 0;
719 static sense_reason_t
720 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
721 u32 sectors, bool is_write)
723 u8 protect = cdb[1] >> 5;
724 int sp_ops = cmd->se_sess->sup_prot_ops;
725 int pi_prot_type = dev->dev_attrib.pi_prot_type;
726 bool fabric_prot = false;
728 if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
729 if (unlikely(protect &&
730 !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
731 pr_err("CDB contains protect bit, but device + fabric does"
732 " not advertise PROTECT=1 feature bit\n");
733 return TCM_INVALID_CDB_FIELD;
735 if (cmd->prot_pto)
736 return TCM_NO_SENSE;
739 switch (dev->dev_attrib.pi_prot_type) {
740 case TARGET_DIF_TYPE3_PROT:
741 cmd->reftag_seed = 0xffffffff;
742 break;
743 case TARGET_DIF_TYPE2_PROT:
744 if (protect)
745 return TCM_INVALID_CDB_FIELD;
747 cmd->reftag_seed = cmd->t_task_lba;
748 break;
749 case TARGET_DIF_TYPE1_PROT:
750 cmd->reftag_seed = cmd->t_task_lba;
751 break;
752 case TARGET_DIF_TYPE0_PROT:
754 * See if the fabric supports T10-PI, and the session has been
755 * configured to allow export PROTECT=1 feature bit with backend
756 * devices that don't support T10-PI.
758 fabric_prot = is_write ?
759 !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
760 !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
762 if (fabric_prot && cmd->se_sess->sess_prot_type) {
763 pi_prot_type = cmd->se_sess->sess_prot_type;
764 break;
766 if (!protect)
767 return TCM_NO_SENSE;
768 fallthrough;
769 default:
770 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
771 "PROTECT: 0x%02x\n", cdb[0], protect);
772 return TCM_INVALID_CDB_FIELD;
775 if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
776 return TCM_INVALID_CDB_FIELD;
778 cmd->prot_type = pi_prot_type;
779 cmd->prot_length = dev->prot_length * sectors;
782 * In case protection information exists over the wire
783 * we modify command data length to describe pure data.
784 * The actual transfer length is data length + protection
785 * length
787 if (protect)
788 cmd->data_length = sectors * dev->dev_attrib.block_size;
790 pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
791 "prot_op=%d prot_checks=%d\n",
792 __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
793 cmd->prot_op, cmd->prot_checks);
795 return TCM_NO_SENSE;
798 static int
799 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
801 if (cdb[1] & 0x10) {
802 /* see explanation in spc_emulate_modesense */
803 if (!target_check_fua(dev)) {
804 pr_err("Got CDB: 0x%02x with DPO bit set, but device"
805 " does not advertise support for DPO\n", cdb[0]);
806 return -EINVAL;
809 if (cdb[1] & 0x8) {
810 if (!target_check_fua(dev)) {
811 pr_err("Got CDB: 0x%02x with FUA bit set, but device"
812 " does not advertise support for FUA write\n",
813 cdb[0]);
814 return -EINVAL;
816 cmd->se_cmd_flags |= SCF_FUA;
818 return 0;
821 sense_reason_t
822 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
824 struct se_device *dev = cmd->se_dev;
825 unsigned char *cdb = cmd->t_task_cdb;
826 unsigned int size;
827 u32 sectors = 0;
828 sense_reason_t ret;
830 cmd->protocol_data = ops;
832 switch (cdb[0]) {
833 case READ_6:
834 sectors = transport_get_sectors_6(cdb);
835 cmd->t_task_lba = transport_lba_21(cdb);
836 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
837 cmd->execute_cmd = sbc_execute_rw;
838 break;
839 case READ_10:
840 sectors = transport_get_sectors_10(cdb);
841 cmd->t_task_lba = transport_lba_32(cdb);
843 if (sbc_check_dpofua(dev, cmd, cdb))
844 return TCM_INVALID_CDB_FIELD;
846 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
847 if (ret)
848 return ret;
850 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
851 cmd->execute_cmd = sbc_execute_rw;
852 break;
853 case READ_12:
854 sectors = transport_get_sectors_12(cdb);
855 cmd->t_task_lba = transport_lba_32(cdb);
857 if (sbc_check_dpofua(dev, cmd, cdb))
858 return TCM_INVALID_CDB_FIELD;
860 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
861 if (ret)
862 return ret;
864 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
865 cmd->execute_cmd = sbc_execute_rw;
866 break;
867 case READ_16:
868 sectors = transport_get_sectors_16(cdb);
869 cmd->t_task_lba = transport_lba_64(cdb);
871 if (sbc_check_dpofua(dev, cmd, cdb))
872 return TCM_INVALID_CDB_FIELD;
874 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
875 if (ret)
876 return ret;
878 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
879 cmd->execute_cmd = sbc_execute_rw;
880 break;
881 case WRITE_6:
882 sectors = transport_get_sectors_6(cdb);
883 cmd->t_task_lba = transport_lba_21(cdb);
884 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
885 cmd->execute_cmd = sbc_execute_rw;
886 break;
887 case WRITE_10:
888 case WRITE_VERIFY:
889 sectors = transport_get_sectors_10(cdb);
890 cmd->t_task_lba = transport_lba_32(cdb);
892 if (sbc_check_dpofua(dev, cmd, cdb))
893 return TCM_INVALID_CDB_FIELD;
895 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
896 if (ret)
897 return ret;
899 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
900 cmd->execute_cmd = sbc_execute_rw;
901 break;
902 case WRITE_12:
903 sectors = transport_get_sectors_12(cdb);
904 cmd->t_task_lba = transport_lba_32(cdb);
906 if (sbc_check_dpofua(dev, cmd, cdb))
907 return TCM_INVALID_CDB_FIELD;
909 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
910 if (ret)
911 return ret;
913 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
914 cmd->execute_cmd = sbc_execute_rw;
915 break;
916 case WRITE_16:
917 case WRITE_VERIFY_16:
918 sectors = transport_get_sectors_16(cdb);
919 cmd->t_task_lba = transport_lba_64(cdb);
921 if (sbc_check_dpofua(dev, cmd, cdb))
922 return TCM_INVALID_CDB_FIELD;
924 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
925 if (ret)
926 return ret;
928 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
929 cmd->execute_cmd = sbc_execute_rw;
930 break;
931 case XDWRITEREAD_10:
932 if (cmd->data_direction != DMA_TO_DEVICE ||
933 !(cmd->se_cmd_flags & SCF_BIDI))
934 return TCM_INVALID_CDB_FIELD;
935 sectors = transport_get_sectors_10(cdb);
937 if (sbc_check_dpofua(dev, cmd, cdb))
938 return TCM_INVALID_CDB_FIELD;
940 cmd->t_task_lba = transport_lba_32(cdb);
941 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
944 * Setup BIDI XOR callback to be run after I/O completion.
946 cmd->execute_cmd = sbc_execute_rw;
947 cmd->transport_complete_callback = &xdreadwrite_callback;
948 break;
949 case VARIABLE_LENGTH_CMD:
951 u16 service_action = get_unaligned_be16(&cdb[8]);
952 switch (service_action) {
953 case XDWRITEREAD_32:
954 sectors = transport_get_sectors_32(cdb);
956 if (sbc_check_dpofua(dev, cmd, cdb))
957 return TCM_INVALID_CDB_FIELD;
959 * Use WRITE_32 and READ_32 opcodes for the emulated
960 * XDWRITE_READ_32 logic.
962 cmd->t_task_lba = transport_lba_64_ext(cdb);
963 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
966 * Setup BIDI XOR callback to be run during after I/O
967 * completion.
969 cmd->execute_cmd = sbc_execute_rw;
970 cmd->transport_complete_callback = &xdreadwrite_callback;
971 break;
972 case WRITE_SAME_32:
973 sectors = transport_get_sectors_32(cdb);
974 if (!sectors) {
975 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
976 " supported\n");
977 return TCM_INVALID_CDB_FIELD;
980 size = sbc_get_size(cmd, 1);
981 cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
983 ret = sbc_setup_write_same(cmd, &cdb[10], ops);
984 if (ret)
985 return ret;
986 break;
987 default:
988 pr_err("VARIABLE_LENGTH_CMD service action"
989 " 0x%04x not supported\n", service_action);
990 return TCM_UNSUPPORTED_SCSI_OPCODE;
992 break;
994 case COMPARE_AND_WRITE:
995 if (!dev->dev_attrib.emulate_caw) {
996 pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
997 dev->se_hba->backend->ops->name,
998 config_item_name(&dev->dev_group.cg_item),
999 dev->t10_wwn.unit_serial);
1000 return TCM_UNSUPPORTED_SCSI_OPCODE;
1002 sectors = cdb[13];
1004 * Currently enforce COMPARE_AND_WRITE for a single sector
1006 if (sectors > 1) {
1007 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
1008 " than 1\n", sectors);
1009 return TCM_INVALID_CDB_FIELD;
1011 if (sbc_check_dpofua(dev, cmd, cdb))
1012 return TCM_INVALID_CDB_FIELD;
1015 * Double size because we have two buffers, note that
1016 * zero is not an error..
1018 size = 2 * sbc_get_size(cmd, sectors);
1019 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1020 cmd->t_task_nolb = sectors;
1021 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1022 cmd->execute_cmd = sbc_compare_and_write;
1023 cmd->transport_complete_callback = compare_and_write_callback;
1024 break;
1025 case READ_CAPACITY:
1026 size = READ_CAP_LEN;
1027 cmd->execute_cmd = sbc_emulate_readcapacity;
1028 break;
1029 case SERVICE_ACTION_IN_16:
1030 switch (cmd->t_task_cdb[1] & 0x1f) {
1031 case SAI_READ_CAPACITY_16:
1032 cmd->execute_cmd = sbc_emulate_readcapacity_16;
1033 break;
1034 case SAI_REPORT_REFERRALS:
1035 cmd->execute_cmd = target_emulate_report_referrals;
1036 break;
1037 default:
1038 pr_err("Unsupported SA: 0x%02x\n",
1039 cmd->t_task_cdb[1] & 0x1f);
1040 return TCM_INVALID_CDB_FIELD;
1042 size = get_unaligned_be32(&cdb[10]);
1043 break;
1044 case SYNCHRONIZE_CACHE:
1045 case SYNCHRONIZE_CACHE_16:
1046 if (cdb[0] == SYNCHRONIZE_CACHE) {
1047 sectors = transport_get_sectors_10(cdb);
1048 cmd->t_task_lba = transport_lba_32(cdb);
1049 } else {
1050 sectors = transport_get_sectors_16(cdb);
1051 cmd->t_task_lba = transport_lba_64(cdb);
1053 if (ops->execute_sync_cache) {
1054 cmd->execute_cmd = ops->execute_sync_cache;
1055 goto check_lba;
1057 size = 0;
1058 cmd->execute_cmd = sbc_emulate_noop;
1059 break;
1060 case UNMAP:
1061 if (!ops->execute_unmap)
1062 return TCM_UNSUPPORTED_SCSI_OPCODE;
1064 if (!dev->dev_attrib.emulate_tpu) {
1065 pr_err("Got UNMAP, but backend device has"
1066 " emulate_tpu disabled\n");
1067 return TCM_UNSUPPORTED_SCSI_OPCODE;
1069 size = get_unaligned_be16(&cdb[7]);
1070 cmd->execute_cmd = sbc_execute_unmap;
1071 break;
1072 case WRITE_SAME_16:
1073 sectors = transport_get_sectors_16(cdb);
1074 if (!sectors) {
1075 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1076 return TCM_INVALID_CDB_FIELD;
1079 size = sbc_get_size(cmd, 1);
1080 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1082 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1083 if (ret)
1084 return ret;
1085 break;
1086 case WRITE_SAME:
1087 sectors = transport_get_sectors_10(cdb);
1088 if (!sectors) {
1089 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1090 return TCM_INVALID_CDB_FIELD;
1093 size = sbc_get_size(cmd, 1);
1094 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1097 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1098 * of byte 1 bit 3 UNMAP instead of original reserved field
1100 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1101 if (ret)
1102 return ret;
1103 break;
1104 case VERIFY:
1105 case VERIFY_16:
1106 size = 0;
1107 if (cdb[0] == VERIFY) {
1108 sectors = transport_get_sectors_10(cdb);
1109 cmd->t_task_lba = transport_lba_32(cdb);
1110 } else {
1111 sectors = transport_get_sectors_16(cdb);
1112 cmd->t_task_lba = transport_lba_64(cdb);
1114 cmd->execute_cmd = sbc_emulate_noop;
1115 goto check_lba;
1116 case REZERO_UNIT:
1117 case SEEK_6:
1118 case SEEK_10:
1120 * There are still clients out there which use these old SCSI-2
1121 * commands. This mainly happens when running VMs with legacy
1122 * guest systems, connected via SCSI command pass-through to
1123 * iSCSI targets. Make them happy and return status GOOD.
1125 size = 0;
1126 cmd->execute_cmd = sbc_emulate_noop;
1127 break;
1128 case START_STOP:
1129 size = 0;
1130 cmd->execute_cmd = sbc_emulate_startstop;
1131 break;
1132 default:
1133 ret = spc_parse_cdb(cmd, &size);
1134 if (ret)
1135 return ret;
1138 /* reject any command that we don't have a handler for */
1139 if (!cmd->execute_cmd)
1140 return TCM_UNSUPPORTED_SCSI_OPCODE;
1142 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1143 unsigned long long end_lba;
1144 check_lba:
1145 end_lba = dev->transport->get_blocks(dev) + 1;
1146 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1147 ((cmd->t_task_lba + sectors) > end_lba)) {
1148 pr_err("cmd exceeds last lba %llu "
1149 "(lba %llu, sectors %u)\n",
1150 end_lba, cmd->t_task_lba, sectors);
1151 return TCM_ADDRESS_OUT_OF_RANGE;
1154 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1155 size = sbc_get_size(cmd, sectors);
1158 return target_cmd_size_check(cmd, size);
1160 EXPORT_SYMBOL(sbc_parse_cdb);
1162 u32 sbc_get_device_type(struct se_device *dev)
1164 return TYPE_DISK;
1166 EXPORT_SYMBOL(sbc_get_device_type);
1168 static sense_reason_t
1169 sbc_execute_unmap(struct se_cmd *cmd)
1171 struct sbc_ops *ops = cmd->protocol_data;
1172 struct se_device *dev = cmd->se_dev;
1173 unsigned char *buf, *ptr = NULL;
1174 sector_t lba;
1175 int size;
1176 u32 range;
1177 sense_reason_t ret = 0;
1178 int dl, bd_dl;
1180 /* We never set ANC_SUP */
1181 if (cmd->t_task_cdb[1])
1182 return TCM_INVALID_CDB_FIELD;
1184 if (cmd->data_length == 0) {
1185 target_complete_cmd(cmd, SAM_STAT_GOOD);
1186 return 0;
1189 if (cmd->data_length < 8) {
1190 pr_warn("UNMAP parameter list length %u too small\n",
1191 cmd->data_length);
1192 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1195 buf = transport_kmap_data_sg(cmd);
1196 if (!buf)
1197 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1199 dl = get_unaligned_be16(&buf[0]);
1200 bd_dl = get_unaligned_be16(&buf[2]);
1202 size = cmd->data_length - 8;
1203 if (bd_dl > size)
1204 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1205 cmd->data_length, bd_dl);
1206 else
1207 size = bd_dl;
1209 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1210 ret = TCM_INVALID_PARAMETER_LIST;
1211 goto err;
1214 /* First UNMAP block descriptor starts at 8 byte offset */
1215 ptr = &buf[8];
1216 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1217 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1219 while (size >= 16) {
1220 lba = get_unaligned_be64(&ptr[0]);
1221 range = get_unaligned_be32(&ptr[8]);
1222 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1223 (unsigned long long)lba, range);
1225 if (range > dev->dev_attrib.max_unmap_lba_count) {
1226 ret = TCM_INVALID_PARAMETER_LIST;
1227 goto err;
1230 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1231 ret = TCM_ADDRESS_OUT_OF_RANGE;
1232 goto err;
1235 if (range) {
1236 ret = ops->execute_unmap(cmd, lba, range);
1237 if (ret)
1238 goto err;
1241 ptr += 16;
1242 size -= 16;
1245 err:
1246 transport_kunmap_data_sg(cmd);
1247 if (!ret)
1248 target_complete_cmd(cmd, GOOD);
1249 return ret;
1252 void
1253 sbc_dif_generate(struct se_cmd *cmd)
1255 struct se_device *dev = cmd->se_dev;
1256 struct t10_pi_tuple *sdt;
1257 struct scatterlist *dsg = cmd->t_data_sg, *psg;
1258 sector_t sector = cmd->t_task_lba;
1259 void *daddr, *paddr;
1260 int i, j, offset = 0;
1261 unsigned int block_size = dev->dev_attrib.block_size;
1263 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1264 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1265 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1267 for (j = 0; j < psg->length;
1268 j += sizeof(*sdt)) {
1269 __u16 crc;
1270 unsigned int avail;
1272 if (offset >= dsg->length) {
1273 offset -= dsg->length;
1274 kunmap_atomic(daddr - dsg->offset);
1275 dsg = sg_next(dsg);
1276 if (!dsg) {
1277 kunmap_atomic(paddr - psg->offset);
1278 return;
1280 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1283 sdt = paddr + j;
1284 avail = min(block_size, dsg->length - offset);
1285 crc = crc_t10dif(daddr + offset, avail);
1286 if (avail < block_size) {
1287 kunmap_atomic(daddr - dsg->offset);
1288 dsg = sg_next(dsg);
1289 if (!dsg) {
1290 kunmap_atomic(paddr - psg->offset);
1291 return;
1293 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1294 offset = block_size - avail;
1295 crc = crc_t10dif_update(crc, daddr, offset);
1296 } else {
1297 offset += block_size;
1300 sdt->guard_tag = cpu_to_be16(crc);
1301 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1302 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1303 sdt->app_tag = 0;
1305 pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1306 " app_tag: 0x%04x ref_tag: %u\n",
1307 (cmd->data_direction == DMA_TO_DEVICE) ?
1308 "WRITE" : "READ", (unsigned long long)sector,
1309 sdt->guard_tag, sdt->app_tag,
1310 be32_to_cpu(sdt->ref_tag));
1312 sector++;
1315 kunmap_atomic(daddr - dsg->offset);
1316 kunmap_atomic(paddr - psg->offset);
1320 static sense_reason_t
1321 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1322 __u16 crc, sector_t sector, unsigned int ei_lba)
1324 __be16 csum;
1326 if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1327 goto check_ref;
1329 csum = cpu_to_be16(crc);
1331 if (sdt->guard_tag != csum) {
1332 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1333 " csum 0x%04x\n", (unsigned long long)sector,
1334 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1335 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1338 check_ref:
1339 if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1340 return 0;
1342 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1343 be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1344 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1345 " sector MSB: 0x%08x\n", (unsigned long long)sector,
1346 be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1347 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1350 if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1351 be32_to_cpu(sdt->ref_tag) != ei_lba) {
1352 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1353 " ei_lba: 0x%08x\n", (unsigned long long)sector,
1354 be32_to_cpu(sdt->ref_tag), ei_lba);
1355 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1358 return 0;
1361 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1362 struct scatterlist *sg, int sg_off)
1364 struct se_device *dev = cmd->se_dev;
1365 struct scatterlist *psg;
1366 void *paddr, *addr;
1367 unsigned int i, len, left;
1368 unsigned int offset = sg_off;
1370 if (!sg)
1371 return;
1373 left = sectors * dev->prot_length;
1375 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1376 unsigned int psg_len, copied = 0;
1378 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1379 psg_len = min(left, psg->length);
1380 while (psg_len) {
1381 len = min(psg_len, sg->length - offset);
1382 addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1384 if (read)
1385 memcpy(paddr + copied, addr, len);
1386 else
1387 memcpy(addr, paddr + copied, len);
1389 left -= len;
1390 offset += len;
1391 copied += len;
1392 psg_len -= len;
1394 kunmap_atomic(addr - sg->offset - offset);
1396 if (offset >= sg->length) {
1397 sg = sg_next(sg);
1398 offset = 0;
1401 kunmap_atomic(paddr - psg->offset);
1404 EXPORT_SYMBOL(sbc_dif_copy_prot);
1406 sense_reason_t
1407 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1408 unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1410 struct se_device *dev = cmd->se_dev;
1411 struct t10_pi_tuple *sdt;
1412 struct scatterlist *dsg = cmd->t_data_sg;
1413 sector_t sector = start;
1414 void *daddr, *paddr;
1415 int i;
1416 sense_reason_t rc;
1417 int dsg_off = 0;
1418 unsigned int block_size = dev->dev_attrib.block_size;
1420 for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1421 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1422 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1424 for (i = psg_off; i < psg->length &&
1425 sector < start + sectors;
1426 i += sizeof(*sdt)) {
1427 __u16 crc;
1428 unsigned int avail;
1430 if (dsg_off >= dsg->length) {
1431 dsg_off -= dsg->length;
1432 kunmap_atomic(daddr - dsg->offset);
1433 dsg = sg_next(dsg);
1434 if (!dsg) {
1435 kunmap_atomic(paddr - psg->offset);
1436 return 0;
1438 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1441 sdt = paddr + i;
1443 pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1444 " app_tag: 0x%04x ref_tag: %u\n",
1445 (unsigned long long)sector, sdt->guard_tag,
1446 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1448 if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1449 dsg_off += block_size;
1450 goto next;
1453 avail = min(block_size, dsg->length - dsg_off);
1454 crc = crc_t10dif(daddr + dsg_off, avail);
1455 if (avail < block_size) {
1456 kunmap_atomic(daddr - dsg->offset);
1457 dsg = sg_next(dsg);
1458 if (!dsg) {
1459 kunmap_atomic(paddr - psg->offset);
1460 return 0;
1462 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1463 dsg_off = block_size - avail;
1464 crc = crc_t10dif_update(crc, daddr, dsg_off);
1465 } else {
1466 dsg_off += block_size;
1469 rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1470 if (rc) {
1471 kunmap_atomic(daddr - dsg->offset);
1472 kunmap_atomic(paddr - psg->offset);
1473 cmd->sense_info = sector;
1474 return rc;
1476 next:
1477 sector++;
1478 ei_lba++;
1481 psg_off = 0;
1482 kunmap_atomic(daddr - dsg->offset);
1483 kunmap_atomic(paddr - psg->offset);
1486 return 0;
1488 EXPORT_SYMBOL(sbc_dif_verify);