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 <linux/unaligned.h>
16 #include <scsi/scsi_proto.h>
17 #include <scsi/scsi_tcq.h>
18
19 #include <target/target_core_base.h>
20 #include <target/target_core_backend.h>
21 #include <target/target_core_fabric.h>
22
23 #include "target_core_internal.h"
24 #include "target_core_ua.h"
25 #include "target_core_alua.h"
26
27 static sense_reason_t
28 sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char, u32, bool);
29 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
30
31 static sense_reason_t
sbc_emulate_readcapacity(struct se_cmd * cmd)32 sbc_emulate_readcapacity(struct se_cmd *cmd)
33 {
34 struct se_device *dev = cmd->se_dev;
35 unsigned char *cdb = cmd->t_task_cdb;
36 unsigned long long blocks_long = dev->transport->get_blocks(dev);
37 unsigned char *rbuf;
38 unsigned char buf[8];
39 u32 blocks;
40
41 /*
42 * SBC-2 says:
43 * If the PMI bit is set to zero and the LOGICAL BLOCK
44 * ADDRESS field is not set to zero, the device server shall
45 * terminate the command with CHECK CONDITION status with
46 * the sense key set to ILLEGAL REQUEST and the additional
47 * sense code set to INVALID FIELD IN CDB.
48 *
49 * In SBC-3, these fields are obsolete, but some SCSI
50 * compliance tests actually check this, so we might as well
51 * follow SBC-2.
52 */
53 if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
54 return TCM_INVALID_CDB_FIELD;
55
56 if (blocks_long >= 0x00000000ffffffff)
57 blocks = 0xffffffff;
58 else
59 blocks = (u32)blocks_long;
60
61 put_unaligned_be32(blocks, &buf[0]);
62 put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
63
64 rbuf = transport_kmap_data_sg(cmd);
65 if (rbuf) {
66 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
67 transport_kunmap_data_sg(cmd);
68 }
69
70 target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, 8);
71 return 0;
72 }
73
74 static sense_reason_t
sbc_emulate_readcapacity_16(struct se_cmd * cmd)75 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
76 {
77 struct se_device *dev = cmd->se_dev;
78 struct se_session *sess = cmd->se_sess;
79 int pi_prot_type = dev->dev_attrib.pi_prot_type;
80
81 unsigned char *rbuf;
82 unsigned char buf[32];
83 unsigned long long blocks = dev->transport->get_blocks(dev);
84
85 memset(buf, 0, sizeof(buf));
86 put_unaligned_be64(blocks, &buf[0]);
87 put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
88 /*
89 * Set P_TYPE and PROT_EN bits for DIF support
90 */
91 if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
92 /*
93 * Only override a device's pi_prot_type if no T10-PI is
94 * available, and sess_prot_type has been explicitly enabled.
95 */
96 if (!pi_prot_type)
97 pi_prot_type = sess->sess_prot_type;
98
99 if (pi_prot_type)
100 buf[12] = (pi_prot_type - 1) << 1 | 0x1;
101 }
102
103 if (dev->transport->get_lbppbe)
104 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
105
106 if (dev->transport->get_alignment_offset_lbas) {
107 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
108
109 put_unaligned_be16(lalba, &buf[14]);
110 }
111
112 /*
113 * Set Thin Provisioning Enable bit following sbc3r22 in section
114 * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
115 */
116 if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
117 buf[14] |= 0x80;
118
119 /*
120 * LBPRZ signifies that zeroes will be read back from an LBA after
121 * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2)
122 */
123 if (dev->dev_attrib.unmap_zeroes_data)
124 buf[14] |= 0x40;
125 }
126
127 rbuf = transport_kmap_data_sg(cmd);
128 if (rbuf) {
129 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
130 transport_kunmap_data_sg(cmd);
131 }
132
133 target_complete_cmd_with_length(cmd, SAM_STAT_GOOD, 32);
134 return 0;
135 }
136
137 static sense_reason_t
sbc_emulate_startstop(struct se_cmd * cmd)138 sbc_emulate_startstop(struct se_cmd *cmd)
139 {
140 unsigned char *cdb = cmd->t_task_cdb;
141
142 /*
143 * See sbc3r36 section 5.25
144 * Immediate bit should be set since there is nothing to complete
145 * POWER CONDITION MODIFIER 0h
146 */
147 if (!(cdb[1] & 1) || cdb[2] || cdb[3])
148 return TCM_INVALID_CDB_FIELD;
149
150 /*
151 * See sbc3r36 section 5.25
152 * POWER CONDITION 0h START_VALID - process START and LOEJ
153 */
154 if (cdb[4] >> 4 & 0xf)
155 return TCM_INVALID_CDB_FIELD;
156
157 /*
158 * See sbc3r36 section 5.25
159 * LOEJ 0h - nothing to load or unload
160 * START 1h - we are ready
161 */
162 if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
163 return TCM_INVALID_CDB_FIELD;
164
165 target_complete_cmd(cmd, SAM_STAT_GOOD);
166 return 0;
167 }
168
sbc_get_write_same_sectors(struct se_cmd * cmd)169 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
170 {
171 u32 num_blocks;
172
173 if (cmd->t_task_cdb[0] == WRITE_SAME)
174 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
175 else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
176 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
177 else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
178 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
179
180 /*
181 * Use the explicit range when non zero is supplied, otherwise calculate
182 * the remaining range based on ->get_blocks() - starting LBA.
183 */
184 if (num_blocks)
185 return num_blocks;
186
187 return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
188 cmd->t_task_lba + 1;
189 }
190 EXPORT_SYMBOL(sbc_get_write_same_sectors);
191
192 static sense_reason_t
sbc_execute_write_same_unmap(struct se_cmd * cmd)193 sbc_execute_write_same_unmap(struct se_cmd *cmd)
194 {
195 struct 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
209 static sense_reason_t
sbc_emulate_noop(struct se_cmd * cmd)210 sbc_emulate_noop(struct se_cmd *cmd)
211 {
212 target_complete_cmd(cmd, SAM_STAT_GOOD);
213 return 0;
214 }
215
sbc_get_size(struct se_cmd * cmd,u32 sectors)216 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
217 {
218 return cmd->se_dev->dev_attrib.block_size * sectors;
219 }
220
transport_get_sectors_6(unsigned char * cdb)221 static inline u32 transport_get_sectors_6(unsigned char *cdb)
222 {
223 /*
224 * Use 8-bit sector value. SBC-3 says:
225 *
226 * A TRANSFER LENGTH field set to zero specifies that 256
227 * logical blocks shall be written. Any other value
228 * specifies the number of logical blocks that shall be
229 * written.
230 */
231 return cdb[4] ? : 256;
232 }
233
transport_get_sectors_10(unsigned char * cdb)234 static inline u32 transport_get_sectors_10(unsigned char *cdb)
235 {
236 return get_unaligned_be16(&cdb[7]);
237 }
238
transport_get_sectors_12(unsigned char * cdb)239 static inline u32 transport_get_sectors_12(unsigned char *cdb)
240 {
241 return get_unaligned_be32(&cdb[6]);
242 }
243
transport_get_sectors_16(unsigned char * cdb)244 static inline u32 transport_get_sectors_16(unsigned char *cdb)
245 {
246 return get_unaligned_be32(&cdb[10]);
247 }
248
249 /*
250 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
251 */
transport_get_sectors_32(unsigned char * cdb)252 static inline u32 transport_get_sectors_32(unsigned char *cdb)
253 {
254 return get_unaligned_be32(&cdb[28]);
255
256 }
257
transport_lba_21(unsigned char * cdb)258 static inline u32 transport_lba_21(unsigned char *cdb)
259 {
260 return get_unaligned_be24(&cdb[1]) & 0x1fffff;
261 }
262
transport_lba_32(unsigned char * cdb)263 static inline u32 transport_lba_32(unsigned char *cdb)
264 {
265 return get_unaligned_be32(&cdb[2]);
266 }
267
transport_lba_64(unsigned char * cdb)268 static inline unsigned long long transport_lba_64(unsigned char *cdb)
269 {
270 return get_unaligned_be64(&cdb[2]);
271 }
272
273 static sense_reason_t
sbc_setup_write_same(struct se_cmd * cmd,unsigned char flags,struct exec_cmd_ops * ops)274 sbc_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
341 static sense_reason_t
sbc_execute_rw(struct se_cmd * cmd)342 sbc_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
compare_and_write_post(struct se_cmd * cmd,bool success,int * post_ret)350 static 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 */
378 static sense_reason_t
compare_and_write_do_cmp(struct scatterlist * read_sgl,unsigned int read_nents,struct scatterlist * cmp_sgl,unsigned int cmp_nents,unsigned int cmp_len,unsigned int * miscmp_off)379 compare_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");
431 out:
432 kfree(buf);
433 return ret;
434 }
435
compare_and_write_callback(struct se_cmd * cmd,bool success,int * post_ret)436 static 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
557 out:
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
567 static sense_reason_t
sbc_compare_and_write(struct se_cmd * cmd)568 sbc_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
605 static int
sbc_set_prot_op_checks(u8 protect,bool fabric_prot,enum target_prot_type prot_type,bool is_write,struct se_cmd * cmd)606 sbc_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
666 static sense_reason_t
sbc_check_prot(struct se_device * dev,struct se_cmd * cmd,unsigned char protect,u32 sectors,bool is_write)667 sbc_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
744 static int
sbc_check_dpofua(struct se_device * dev,struct se_cmd * cmd,unsigned char * cdb)745 sbc_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
767 static sense_reason_t
sbc_check_atomic(struct se_device * dev,struct se_cmd * cmd,unsigned char * cdb)768 sbc_check_atomic(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
769 {
770 struct se_dev_attrib *attrib = &dev->dev_attrib;
771 u16 boundary, transfer_len;
772 u64 lba;
773
774 lba = transport_lba_64(cdb);
775 boundary = get_unaligned_be16(&cdb[10]);
776 transfer_len = get_unaligned_be16(&cdb[12]);
777
778 if (!attrib->atomic_max_len)
779 return TCM_UNSUPPORTED_SCSI_OPCODE;
780
781 if (boundary) {
782 if (transfer_len > attrib->atomic_max_with_boundary)
783 return TCM_INVALID_CDB_FIELD;
784
785 if (boundary > attrib->atomic_max_boundary)
786 return TCM_INVALID_CDB_FIELD;
787 } else {
788 if (transfer_len > attrib->atomic_max_len)
789 return TCM_INVALID_CDB_FIELD;
790 }
791
792 if (attrib->atomic_granularity) {
793 if (transfer_len % attrib->atomic_granularity)
794 return TCM_INVALID_CDB_FIELD;
795
796 if (boundary && boundary % attrib->atomic_granularity)
797 return TCM_INVALID_CDB_FIELD;
798 }
799
800 if (dev->dev_attrib.atomic_alignment) {
801 u64 _lba = lba;
802
803 if (do_div(_lba, dev->dev_attrib.atomic_alignment))
804 return TCM_INVALID_CDB_FIELD;
805 }
806
807 return 0;
808 }
809
810 sense_reason_t
sbc_parse_cdb(struct se_cmd * cmd,struct exec_cmd_ops * ops)811 sbc_parse_cdb(struct se_cmd *cmd, struct exec_cmd_ops *ops)
812 {
813 struct se_device *dev = cmd->se_dev;
814 unsigned char *cdb = cmd->t_task_cdb;
815 unsigned int size;
816 u32 sectors = 0;
817 sense_reason_t ret;
818
819 cmd->protocol_data = ops;
820
821 switch (cdb[0]) {
822 case READ_6:
823 sectors = transport_get_sectors_6(cdb);
824 cmd->t_task_lba = transport_lba_21(cdb);
825 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
826 cmd->execute_cmd = sbc_execute_rw;
827 break;
828 case READ_10:
829 sectors = transport_get_sectors_10(cdb);
830 cmd->t_task_lba = transport_lba_32(cdb);
831
832 if (sbc_check_dpofua(dev, cmd, cdb))
833 return TCM_INVALID_CDB_FIELD;
834
835 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
836 if (ret)
837 return ret;
838
839 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
840 cmd->execute_cmd = sbc_execute_rw;
841 break;
842 case READ_12:
843 sectors = transport_get_sectors_12(cdb);
844 cmd->t_task_lba = transport_lba_32(cdb);
845
846 if (sbc_check_dpofua(dev, cmd, cdb))
847 return TCM_INVALID_CDB_FIELD;
848
849 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
850 if (ret)
851 return ret;
852
853 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
854 cmd->execute_cmd = sbc_execute_rw;
855 break;
856 case READ_16:
857 sectors = transport_get_sectors_16(cdb);
858 cmd->t_task_lba = transport_lba_64(cdb);
859
860 if (sbc_check_dpofua(dev, cmd, cdb))
861 return TCM_INVALID_CDB_FIELD;
862
863 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, false);
864 if (ret)
865 return ret;
866
867 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
868 cmd->execute_cmd = sbc_execute_rw;
869 break;
870 case WRITE_6:
871 sectors = transport_get_sectors_6(cdb);
872 cmd->t_task_lba = transport_lba_21(cdb);
873 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
874 cmd->execute_cmd = sbc_execute_rw;
875 break;
876 case WRITE_10:
877 case WRITE_VERIFY:
878 sectors = transport_get_sectors_10(cdb);
879 cmd->t_task_lba = transport_lba_32(cdb);
880
881 if (sbc_check_dpofua(dev, cmd, cdb))
882 return TCM_INVALID_CDB_FIELD;
883
884 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
885 if (ret)
886 return ret;
887
888 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
889 cmd->execute_cmd = sbc_execute_rw;
890 break;
891 case WRITE_12:
892 sectors = transport_get_sectors_12(cdb);
893 cmd->t_task_lba = transport_lba_32(cdb);
894
895 if (sbc_check_dpofua(dev, cmd, cdb))
896 return TCM_INVALID_CDB_FIELD;
897
898 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
899 if (ret)
900 return ret;
901
902 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
903 cmd->execute_cmd = sbc_execute_rw;
904 break;
905 case WRITE_16:
906 case WRITE_VERIFY_16:
907 case WRITE_ATOMIC_16:
908 sectors = transport_get_sectors_16(cdb);
909 cmd->t_task_lba = transport_lba_64(cdb);
910
911 if (sbc_check_dpofua(dev, cmd, cdb))
912 return TCM_INVALID_CDB_FIELD;
913
914 ret = sbc_check_prot(dev, cmd, cdb[1] >> 5, sectors, true);
915 if (ret)
916 return ret;
917
918 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
919 if (cdb[0] == WRITE_ATOMIC_16) {
920 cmd->se_cmd_flags |= SCF_ATOMIC;
921
922 ret = sbc_check_atomic(dev, cmd, cdb);
923 if (ret)
924 return ret;
925 }
926 cmd->execute_cmd = sbc_execute_rw;
927 break;
928 case VARIABLE_LENGTH_CMD:
929 {
930 u16 service_action = get_unaligned_be16(&cdb[8]);
931 switch (service_action) {
932 case WRITE_SAME_32:
933 sectors = transport_get_sectors_32(cdb);
934 if (!sectors) {
935 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
936 " supported\n");
937 return TCM_INVALID_CDB_FIELD;
938 }
939
940 size = sbc_get_size(cmd, 1);
941 cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
942
943 ret = sbc_setup_write_same(cmd, cdb[10], ops);
944 if (ret)
945 return ret;
946 break;
947 default:
948 pr_err("VARIABLE_LENGTH_CMD service action"
949 " 0x%04x not supported\n", service_action);
950 return TCM_UNSUPPORTED_SCSI_OPCODE;
951 }
952 break;
953 }
954 case COMPARE_AND_WRITE:
955 if (!dev->dev_attrib.emulate_caw) {
956 pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject COMPARE_AND_WRITE\n",
957 dev->se_hba->backend->ops->name,
958 config_item_name(&dev->dev_group.cg_item),
959 dev->t10_wwn.unit_serial);
960 return TCM_UNSUPPORTED_SCSI_OPCODE;
961 }
962 sectors = cdb[13];
963 /*
964 * Currently enforce COMPARE_AND_WRITE for a single sector
965 */
966 if (sectors > 1) {
967 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
968 " than 1\n", sectors);
969 return TCM_INVALID_CDB_FIELD;
970 }
971 if (sbc_check_dpofua(dev, cmd, cdb))
972 return TCM_INVALID_CDB_FIELD;
973
974 /*
975 * Double size because we have two buffers, note that
976 * zero is not an error..
977 */
978 size = 2 * sbc_get_size(cmd, sectors);
979 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
980 cmd->t_task_nolb = sectors;
981 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
982 cmd->execute_cmd = sbc_compare_and_write;
983 cmd->transport_complete_callback = compare_and_write_callback;
984 break;
985 case READ_CAPACITY:
986 size = READ_CAP_LEN;
987 cmd->execute_cmd = sbc_emulate_readcapacity;
988 break;
989 case SERVICE_ACTION_IN_16:
990 switch (cmd->t_task_cdb[1] & 0x1f) {
991 case SAI_READ_CAPACITY_16:
992 cmd->execute_cmd = sbc_emulate_readcapacity_16;
993 break;
994 case SAI_REPORT_REFERRALS:
995 cmd->execute_cmd = target_emulate_report_referrals;
996 break;
997 default:
998 pr_err("Unsupported SA: 0x%02x\n",
999 cmd->t_task_cdb[1] & 0x1f);
1000 return TCM_INVALID_CDB_FIELD;
1001 }
1002 size = get_unaligned_be32(&cdb[10]);
1003 break;
1004 case SYNCHRONIZE_CACHE:
1005 case SYNCHRONIZE_CACHE_16:
1006 if (cdb[0] == SYNCHRONIZE_CACHE) {
1007 sectors = transport_get_sectors_10(cdb);
1008 cmd->t_task_lba = transport_lba_32(cdb);
1009 } else {
1010 sectors = transport_get_sectors_16(cdb);
1011 cmd->t_task_lba = transport_lba_64(cdb);
1012 }
1013 if (ops->execute_sync_cache) {
1014 cmd->execute_cmd = ops->execute_sync_cache;
1015 goto check_lba;
1016 }
1017 size = 0;
1018 cmd->execute_cmd = sbc_emulate_noop;
1019 break;
1020 case UNMAP:
1021 if (!ops->execute_unmap)
1022 return TCM_UNSUPPORTED_SCSI_OPCODE;
1023
1024 if (!dev->dev_attrib.emulate_tpu) {
1025 pr_err("Got UNMAP, but backend device has"
1026 " emulate_tpu disabled\n");
1027 return TCM_UNSUPPORTED_SCSI_OPCODE;
1028 }
1029 size = get_unaligned_be16(&cdb[7]);
1030 cmd->execute_cmd = sbc_execute_unmap;
1031 break;
1032 case WRITE_SAME_16:
1033 sectors = transport_get_sectors_16(cdb);
1034 if (!sectors) {
1035 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1036 return TCM_INVALID_CDB_FIELD;
1037 }
1038
1039 size = sbc_get_size(cmd, 1);
1040 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1041
1042 ret = sbc_setup_write_same(cmd, cdb[1], ops);
1043 if (ret)
1044 return ret;
1045 break;
1046 case WRITE_SAME:
1047 sectors = transport_get_sectors_10(cdb);
1048 if (!sectors) {
1049 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1050 return TCM_INVALID_CDB_FIELD;
1051 }
1052
1053 size = sbc_get_size(cmd, 1);
1054 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1055
1056 /*
1057 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1058 * of byte 1 bit 3 UNMAP instead of original reserved field
1059 */
1060 ret = sbc_setup_write_same(cmd, cdb[1], ops);
1061 if (ret)
1062 return ret;
1063 break;
1064 case VERIFY:
1065 case VERIFY_16:
1066 size = 0;
1067 if (cdb[0] == VERIFY) {
1068 sectors = transport_get_sectors_10(cdb);
1069 cmd->t_task_lba = transport_lba_32(cdb);
1070 } else {
1071 sectors = transport_get_sectors_16(cdb);
1072 cmd->t_task_lba = transport_lba_64(cdb);
1073 }
1074 cmd->execute_cmd = sbc_emulate_noop;
1075 goto check_lba;
1076 case REZERO_UNIT:
1077 case SEEK_6:
1078 case SEEK_10:
1079 /*
1080 * There are still clients out there which use these old SCSI-2
1081 * commands. This mainly happens when running VMs with legacy
1082 * guest systems, connected via SCSI command pass-through to
1083 * iSCSI targets. Make them happy and return status GOOD.
1084 */
1085 size = 0;
1086 cmd->execute_cmd = sbc_emulate_noop;
1087 break;
1088 case START_STOP:
1089 size = 0;
1090 cmd->execute_cmd = sbc_emulate_startstop;
1091 break;
1092 default:
1093 ret = spc_parse_cdb(cmd, &size);
1094 if (ret)
1095 return ret;
1096 }
1097
1098 /* reject any command that we don't have a handler for */
1099 if (!cmd->execute_cmd)
1100 return TCM_UNSUPPORTED_SCSI_OPCODE;
1101
1102 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1103 unsigned long long end_lba;
1104 check_lba:
1105 end_lba = dev->transport->get_blocks(dev) + 1;
1106 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1107 ((cmd->t_task_lba + sectors) > end_lba)) {
1108 pr_err("cmd exceeds last lba %llu "
1109 "(lba %llu, sectors %u)\n",
1110 end_lba, cmd->t_task_lba, sectors);
1111 return TCM_ADDRESS_OUT_OF_RANGE;
1112 }
1113
1114 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1115 size = sbc_get_size(cmd, sectors);
1116 }
1117
1118 return target_cmd_size_check(cmd, size);
1119 }
1120 EXPORT_SYMBOL(sbc_parse_cdb);
1121
sbc_get_device_type(struct se_device * dev)1122 u32 sbc_get_device_type(struct se_device *dev)
1123 {
1124 return TYPE_DISK;
1125 }
1126 EXPORT_SYMBOL(sbc_get_device_type);
1127
1128 static sense_reason_t
sbc_execute_unmap(struct se_cmd * cmd)1129 sbc_execute_unmap(struct se_cmd *cmd)
1130 {
1131 struct exec_cmd_ops *ops = cmd->protocol_data;
1132 struct se_device *dev = cmd->se_dev;
1133 unsigned char *buf, *ptr = NULL;
1134 sector_t lba;
1135 int size;
1136 u32 range;
1137 sense_reason_t ret = 0;
1138 int dl, bd_dl;
1139
1140 /* We never set ANC_SUP */
1141 if (cmd->t_task_cdb[1])
1142 return TCM_INVALID_CDB_FIELD;
1143
1144 if (cmd->data_length == 0) {
1145 target_complete_cmd(cmd, SAM_STAT_GOOD);
1146 return 0;
1147 }
1148
1149 if (cmd->data_length < 8) {
1150 pr_warn("UNMAP parameter list length %u too small\n",
1151 cmd->data_length);
1152 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1153 }
1154
1155 buf = transport_kmap_data_sg(cmd);
1156 if (!buf)
1157 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1158
1159 dl = get_unaligned_be16(&buf[0]);
1160 bd_dl = get_unaligned_be16(&buf[2]);
1161
1162 size = cmd->data_length - 8;
1163 if (bd_dl > size)
1164 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1165 cmd->data_length, bd_dl);
1166 else
1167 size = bd_dl;
1168
1169 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1170 ret = TCM_INVALID_PARAMETER_LIST;
1171 goto err;
1172 }
1173
1174 /* First UNMAP block descriptor starts at 8 byte offset */
1175 ptr = &buf[8];
1176 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1177 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1178
1179 while (size >= 16) {
1180 lba = get_unaligned_be64(&ptr[0]);
1181 range = get_unaligned_be32(&ptr[8]);
1182 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1183 (unsigned long long)lba, range);
1184
1185 if (range > dev->dev_attrib.max_unmap_lba_count) {
1186 ret = TCM_INVALID_PARAMETER_LIST;
1187 goto err;
1188 }
1189
1190 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1191 ret = TCM_ADDRESS_OUT_OF_RANGE;
1192 goto err;
1193 }
1194
1195 if (range) {
1196 ret = ops->execute_unmap(cmd, lba, range);
1197 if (ret)
1198 goto err;
1199 }
1200
1201 ptr += 16;
1202 size -= 16;
1203 }
1204
1205 err:
1206 transport_kunmap_data_sg(cmd);
1207 if (!ret)
1208 target_complete_cmd(cmd, SAM_STAT_GOOD);
1209 return ret;
1210 }
1211
1212 void
sbc_dif_generate(struct se_cmd * cmd)1213 sbc_dif_generate(struct se_cmd *cmd)
1214 {
1215 struct se_device *dev = cmd->se_dev;
1216 struct t10_pi_tuple *sdt;
1217 struct scatterlist *dsg = cmd->t_data_sg, *psg;
1218 sector_t sector = cmd->t_task_lba;
1219 void *daddr, *paddr;
1220 int i, j, offset = 0;
1221 unsigned int block_size = dev->dev_attrib.block_size;
1222
1223 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1224 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1225 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1226
1227 for (j = 0; j < psg->length;
1228 j += sizeof(*sdt)) {
1229 __u16 crc;
1230 unsigned int avail;
1231
1232 if (offset >= dsg->length) {
1233 offset -= dsg->length;
1234 kunmap_atomic(daddr - dsg->offset);
1235 dsg = sg_next(dsg);
1236 if (!dsg) {
1237 kunmap_atomic(paddr - psg->offset);
1238 return;
1239 }
1240 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1241 }
1242
1243 sdt = paddr + j;
1244 avail = min(block_size, dsg->length - offset);
1245 crc = crc_t10dif(daddr + offset, avail);
1246 if (avail < block_size) {
1247 kunmap_atomic(daddr - dsg->offset);
1248 dsg = sg_next(dsg);
1249 if (!dsg) {
1250 kunmap_atomic(paddr - psg->offset);
1251 return;
1252 }
1253 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1254 offset = block_size - avail;
1255 crc = crc_t10dif_update(crc, daddr, offset);
1256 } else {
1257 offset += block_size;
1258 }
1259
1260 sdt->guard_tag = cpu_to_be16(crc);
1261 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1262 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1263 sdt->app_tag = 0;
1264
1265 pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1266 " app_tag: 0x%04x ref_tag: %u\n",
1267 (cmd->data_direction == DMA_TO_DEVICE) ?
1268 "WRITE" : "READ", (unsigned long long)sector,
1269 sdt->guard_tag, sdt->app_tag,
1270 be32_to_cpu(sdt->ref_tag));
1271
1272 sector++;
1273 }
1274
1275 kunmap_atomic(daddr - dsg->offset);
1276 kunmap_atomic(paddr - psg->offset);
1277 }
1278 }
1279
1280 static sense_reason_t
sbc_dif_v1_verify(struct se_cmd * cmd,struct t10_pi_tuple * sdt,__u16 crc,sector_t sector,unsigned int ei_lba)1281 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1282 __u16 crc, sector_t sector, unsigned int ei_lba)
1283 {
1284 __be16 csum;
1285
1286 if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1287 goto check_ref;
1288
1289 csum = cpu_to_be16(crc);
1290
1291 if (sdt->guard_tag != csum) {
1292 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1293 " csum 0x%04x\n", (unsigned long long)sector,
1294 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1295 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1296 }
1297
1298 check_ref:
1299 if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1300 return 0;
1301
1302 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1303 be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1304 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1305 " sector MSB: 0x%08x\n", (unsigned long long)sector,
1306 be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1307 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1308 }
1309
1310 if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1311 be32_to_cpu(sdt->ref_tag) != ei_lba) {
1312 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1313 " ei_lba: 0x%08x\n", (unsigned long long)sector,
1314 be32_to_cpu(sdt->ref_tag), ei_lba);
1315 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1316 }
1317
1318 return 0;
1319 }
1320
sbc_dif_copy_prot(struct se_cmd * cmd,unsigned int sectors,bool read,struct scatterlist * sg,int sg_off)1321 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1322 struct scatterlist *sg, int sg_off)
1323 {
1324 struct se_device *dev = cmd->se_dev;
1325 struct scatterlist *psg;
1326 void *paddr, *addr;
1327 unsigned int i, len, left;
1328 unsigned int offset = sg_off;
1329
1330 if (!sg)
1331 return;
1332
1333 left = sectors * dev->prot_length;
1334
1335 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1336 unsigned int psg_len, copied = 0;
1337
1338 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1339 psg_len = min(left, psg->length);
1340 while (psg_len) {
1341 len = min(psg_len, sg->length - offset);
1342 addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1343
1344 if (read)
1345 memcpy(paddr + copied, addr, len);
1346 else
1347 memcpy(addr, paddr + copied, len);
1348
1349 left -= len;
1350 offset += len;
1351 copied += len;
1352 psg_len -= len;
1353
1354 kunmap_atomic(addr - sg->offset - offset);
1355
1356 if (offset >= sg->length) {
1357 sg = sg_next(sg);
1358 offset = 0;
1359 }
1360 }
1361 kunmap_atomic(paddr - psg->offset);
1362 }
1363 }
1364 EXPORT_SYMBOL(sbc_dif_copy_prot);
1365
1366 sense_reason_t
sbc_dif_verify(struct se_cmd * cmd,sector_t start,unsigned int sectors,unsigned int ei_lba,struct scatterlist * psg,int psg_off)1367 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1368 unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1369 {
1370 struct se_device *dev = cmd->se_dev;
1371 struct t10_pi_tuple *sdt;
1372 struct scatterlist *dsg = cmd->t_data_sg;
1373 sector_t sector = start;
1374 void *daddr, *paddr;
1375 int i;
1376 sense_reason_t rc;
1377 int dsg_off = 0;
1378 unsigned int block_size = dev->dev_attrib.block_size;
1379
1380 for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1381 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1382 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1383
1384 for (i = psg_off; i < psg->length &&
1385 sector < start + sectors;
1386 i += sizeof(*sdt)) {
1387 __u16 crc;
1388 unsigned int avail;
1389
1390 if (dsg_off >= dsg->length) {
1391 dsg_off -= dsg->length;
1392 kunmap_atomic(daddr - dsg->offset);
1393 dsg = sg_next(dsg);
1394 if (!dsg) {
1395 kunmap_atomic(paddr - psg->offset);
1396 return 0;
1397 }
1398 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1399 }
1400
1401 sdt = paddr + i;
1402
1403 pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1404 " app_tag: 0x%04x ref_tag: %u\n",
1405 (unsigned long long)sector, sdt->guard_tag,
1406 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1407
1408 if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1409 dsg_off += block_size;
1410 goto next;
1411 }
1412
1413 avail = min(block_size, dsg->length - dsg_off);
1414 crc = crc_t10dif(daddr + dsg_off, avail);
1415 if (avail < block_size) {
1416 kunmap_atomic(daddr - dsg->offset);
1417 dsg = sg_next(dsg);
1418 if (!dsg) {
1419 kunmap_atomic(paddr - psg->offset);
1420 return 0;
1421 }
1422 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1423 dsg_off = block_size - avail;
1424 crc = crc_t10dif_update(crc, daddr, dsg_off);
1425 } else {
1426 dsg_off += block_size;
1427 }
1428
1429 rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1430 if (rc) {
1431 kunmap_atomic(daddr - dsg->offset);
1432 kunmap_atomic(paddr - psg->offset);
1433 cmd->sense_info = sector;
1434 return rc;
1435 }
1436 next:
1437 sector++;
1438 ei_lba++;
1439 }
1440
1441 psg_off = 0;
1442 kunmap_atomic(daddr - dsg->offset);
1443 kunmap_atomic(paddr - psg->offset);
1444 }
1445
1446 return 0;
1447 }
1448 EXPORT_SYMBOL(sbc_dif_verify);
1449