1 /*
2 * SCSI Block Commands (SBC) parsing and emulation.
3 *
4 * (c) Copyright 2002-2012 RisingTide Systems LLC.
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 <asm/unaligned.h>
27 #include <scsi/scsi.h>
28
29 #include <target/target_core_base.h>
30 #include <target/target_core_backend.h>
31 #include <target/target_core_fabric.h>
32
33 #include "target_core_internal.h"
34 #include "target_core_ua.h"
35
36
37 static sense_reason_t
sbc_emulate_readcapacity(struct se_cmd * cmd)38 sbc_emulate_readcapacity(struct se_cmd *cmd)
39 {
40 struct se_device *dev = cmd->se_dev;
41 unsigned long long blocks_long = dev->transport->get_blocks(dev);
42 unsigned char *rbuf;
43 unsigned char buf[8];
44 u32 blocks;
45
46 if (blocks_long >= 0x00000000ffffffff)
47 blocks = 0xffffffff;
48 else
49 blocks = (u32)blocks_long;
50
51 buf[0] = (blocks >> 24) & 0xff;
52 buf[1] = (blocks >> 16) & 0xff;
53 buf[2] = (blocks >> 8) & 0xff;
54 buf[3] = blocks & 0xff;
55 buf[4] = (dev->dev_attrib.block_size >> 24) & 0xff;
56 buf[5] = (dev->dev_attrib.block_size >> 16) & 0xff;
57 buf[6] = (dev->dev_attrib.block_size >> 8) & 0xff;
58 buf[7] = dev->dev_attrib.block_size & 0xff;
59
60 rbuf = transport_kmap_data_sg(cmd);
61 if (rbuf) {
62 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
63 transport_kunmap_data_sg(cmd);
64 }
65
66 target_complete_cmd(cmd, GOOD);
67 return 0;
68 }
69
70 static sense_reason_t
sbc_emulate_readcapacity_16(struct se_cmd * cmd)71 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
72 {
73 struct se_device *dev = cmd->se_dev;
74 unsigned char *rbuf;
75 unsigned char buf[32];
76 unsigned long long blocks = dev->transport->get_blocks(dev);
77
78 memset(buf, 0, sizeof(buf));
79 buf[0] = (blocks >> 56) & 0xff;
80 buf[1] = (blocks >> 48) & 0xff;
81 buf[2] = (blocks >> 40) & 0xff;
82 buf[3] = (blocks >> 32) & 0xff;
83 buf[4] = (blocks >> 24) & 0xff;
84 buf[5] = (blocks >> 16) & 0xff;
85 buf[6] = (blocks >> 8) & 0xff;
86 buf[7] = blocks & 0xff;
87 buf[8] = (dev->dev_attrib.block_size >> 24) & 0xff;
88 buf[9] = (dev->dev_attrib.block_size >> 16) & 0xff;
89 buf[10] = (dev->dev_attrib.block_size >> 8) & 0xff;
90 buf[11] = dev->dev_attrib.block_size & 0xff;
91 /*
92 * Set Thin Provisioning Enable bit following sbc3r22 in section
93 * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
94 */
95 if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws)
96 buf[14] = 0x80;
97
98 rbuf = transport_kmap_data_sg(cmd);
99 if (rbuf) {
100 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
101 transport_kunmap_data_sg(cmd);
102 }
103
104 target_complete_cmd(cmd, GOOD);
105 return 0;
106 }
107
sbc_get_write_same_sectors(struct se_cmd * cmd)108 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
109 {
110 u32 num_blocks;
111
112 if (cmd->t_task_cdb[0] == WRITE_SAME)
113 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
114 else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
115 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
116 else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
117 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
118
119 /*
120 * Use the explicit range when non zero is supplied, otherwise calculate
121 * the remaining range based on ->get_blocks() - starting LBA.
122 */
123 if (num_blocks)
124 return num_blocks;
125
126 return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
127 cmd->t_task_lba + 1;
128 }
129 EXPORT_SYMBOL(sbc_get_write_same_sectors);
130
131 static sense_reason_t
sbc_emulate_noop(struct se_cmd * cmd)132 sbc_emulate_noop(struct se_cmd *cmd)
133 {
134 target_complete_cmd(cmd, GOOD);
135 return 0;
136 }
137
sbc_get_size(struct se_cmd * cmd,u32 sectors)138 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
139 {
140 return cmd->se_dev->dev_attrib.block_size * sectors;
141 }
142
sbc_check_valid_sectors(struct se_cmd * cmd)143 static int sbc_check_valid_sectors(struct se_cmd *cmd)
144 {
145 struct se_device *dev = cmd->se_dev;
146 unsigned long long end_lba;
147 u32 sectors;
148
149 sectors = cmd->data_length / dev->dev_attrib.block_size;
150 end_lba = dev->transport->get_blocks(dev) + 1;
151
152 if (cmd->t_task_lba + sectors > end_lba) {
153 pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n",
154 cmd->t_task_lba, sectors, end_lba);
155 return -EINVAL;
156 }
157
158 return 0;
159 }
160
transport_get_sectors_6(unsigned char * cdb)161 static inline u32 transport_get_sectors_6(unsigned char *cdb)
162 {
163 /*
164 * Use 8-bit sector value. SBC-3 says:
165 *
166 * A TRANSFER LENGTH field set to zero specifies that 256
167 * logical blocks shall be written. Any other value
168 * specifies the number of logical blocks that shall be
169 * written.
170 */
171 return cdb[4] ? : 256;
172 }
173
transport_get_sectors_10(unsigned char * cdb)174 static inline u32 transport_get_sectors_10(unsigned char *cdb)
175 {
176 return (u32)(cdb[7] << 8) + cdb[8];
177 }
178
transport_get_sectors_12(unsigned char * cdb)179 static inline u32 transport_get_sectors_12(unsigned char *cdb)
180 {
181 return (u32)(cdb[6] << 24) + (cdb[7] << 16) + (cdb[8] << 8) + cdb[9];
182 }
183
transport_get_sectors_16(unsigned char * cdb)184 static inline u32 transport_get_sectors_16(unsigned char *cdb)
185 {
186 return (u32)(cdb[10] << 24) + (cdb[11] << 16) +
187 (cdb[12] << 8) + cdb[13];
188 }
189
190 /*
191 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
192 */
transport_get_sectors_32(unsigned char * cdb)193 static inline u32 transport_get_sectors_32(unsigned char *cdb)
194 {
195 return (u32)(cdb[28] << 24) + (cdb[29] << 16) +
196 (cdb[30] << 8) + cdb[31];
197
198 }
199
transport_lba_21(unsigned char * cdb)200 static inline u32 transport_lba_21(unsigned char *cdb)
201 {
202 return ((cdb[1] & 0x1f) << 16) | (cdb[2] << 8) | cdb[3];
203 }
204
transport_lba_32(unsigned char * cdb)205 static inline u32 transport_lba_32(unsigned char *cdb)
206 {
207 return (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
208 }
209
transport_lba_64(unsigned char * cdb)210 static inline unsigned long long transport_lba_64(unsigned char *cdb)
211 {
212 unsigned int __v1, __v2;
213
214 __v1 = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
215 __v2 = (cdb[6] << 24) | (cdb[7] << 16) | (cdb[8] << 8) | cdb[9];
216
217 return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
218 }
219
220 /*
221 * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
222 */
transport_lba_64_ext(unsigned char * cdb)223 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
224 {
225 unsigned int __v1, __v2;
226
227 __v1 = (cdb[12] << 24) | (cdb[13] << 16) | (cdb[14] << 8) | cdb[15];
228 __v2 = (cdb[16] << 24) | (cdb[17] << 16) | (cdb[18] << 8) | cdb[19];
229
230 return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
231 }
232
233 static sense_reason_t
sbc_setup_write_same(struct se_cmd * cmd,unsigned char * flags,struct sbc_ops * ops)234 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
235 {
236 unsigned int sectors = sbc_get_write_same_sectors(cmd);
237
238 if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
239 pr_err("WRITE_SAME PBDATA and LBDATA"
240 " bits not supported for Block Discard"
241 " Emulation\n");
242 return TCM_UNSUPPORTED_SCSI_OPCODE;
243 }
244 if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
245 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
246 sectors, cmd->se_dev->dev_attrib.max_write_same_len);
247 return TCM_INVALID_CDB_FIELD;
248 }
249 /*
250 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
251 * translated into block discard requests within backend code.
252 */
253 if (flags[0] & 0x08) {
254 if (!ops->execute_write_same_unmap)
255 return TCM_UNSUPPORTED_SCSI_OPCODE;
256
257 cmd->execute_cmd = ops->execute_write_same_unmap;
258 return 0;
259 }
260 if (!ops->execute_write_same)
261 return TCM_UNSUPPORTED_SCSI_OPCODE;
262
263 cmd->execute_cmd = ops->execute_write_same;
264 return 0;
265 }
266
xdreadwrite_callback(struct se_cmd * cmd)267 static void xdreadwrite_callback(struct se_cmd *cmd)
268 {
269 unsigned char *buf, *addr;
270 struct scatterlist *sg;
271 unsigned int offset;
272 int i;
273 int count;
274 /*
275 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
276 *
277 * 1) read the specified logical block(s);
278 * 2) transfer logical blocks from the data-out buffer;
279 * 3) XOR the logical blocks transferred from the data-out buffer with
280 * the logical blocks read, storing the resulting XOR data in a buffer;
281 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
282 * blocks transferred from the data-out buffer; and
283 * 5) transfer the resulting XOR data to the data-in buffer.
284 */
285 buf = kmalloc(cmd->data_length, GFP_KERNEL);
286 if (!buf) {
287 pr_err("Unable to allocate xor_callback buf\n");
288 return;
289 }
290 /*
291 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
292 * into the locally allocated *buf
293 */
294 sg_copy_to_buffer(cmd->t_data_sg,
295 cmd->t_data_nents,
296 buf,
297 cmd->data_length);
298
299 /*
300 * Now perform the XOR against the BIDI read memory located at
301 * cmd->t_mem_bidi_list
302 */
303
304 offset = 0;
305 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
306 addr = kmap_atomic(sg_page(sg));
307 if (!addr)
308 goto out;
309
310 for (i = 0; i < sg->length; i++)
311 *(addr + sg->offset + i) ^= *(buf + offset + i);
312
313 offset += sg->length;
314 kunmap_atomic(addr);
315 }
316
317 out:
318 kfree(buf);
319 }
320
321 sense_reason_t
sbc_parse_cdb(struct se_cmd * cmd,struct sbc_ops * ops)322 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
323 {
324 struct se_device *dev = cmd->se_dev;
325 unsigned char *cdb = cmd->t_task_cdb;
326 unsigned int size;
327 u32 sectors = 0;
328 sense_reason_t ret;
329
330 switch (cdb[0]) {
331 case READ_6:
332 sectors = transport_get_sectors_6(cdb);
333 cmd->t_task_lba = transport_lba_21(cdb);
334 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
335 cmd->execute_cmd = ops->execute_rw;
336 break;
337 case READ_10:
338 sectors = transport_get_sectors_10(cdb);
339 cmd->t_task_lba = transport_lba_32(cdb);
340 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
341 cmd->execute_cmd = ops->execute_rw;
342 break;
343 case READ_12:
344 sectors = transport_get_sectors_12(cdb);
345 cmd->t_task_lba = transport_lba_32(cdb);
346 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
347 cmd->execute_cmd = ops->execute_rw;
348 break;
349 case READ_16:
350 sectors = transport_get_sectors_16(cdb);
351 cmd->t_task_lba = transport_lba_64(cdb);
352 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
353 cmd->execute_cmd = ops->execute_rw;
354 break;
355 case WRITE_6:
356 sectors = transport_get_sectors_6(cdb);
357 cmd->t_task_lba = transport_lba_21(cdb);
358 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
359 cmd->execute_cmd = ops->execute_rw;
360 break;
361 case WRITE_10:
362 case WRITE_VERIFY:
363 sectors = transport_get_sectors_10(cdb);
364 cmd->t_task_lba = transport_lba_32(cdb);
365 if (cdb[1] & 0x8)
366 cmd->se_cmd_flags |= SCF_FUA;
367 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
368 cmd->execute_cmd = ops->execute_rw;
369 break;
370 case WRITE_12:
371 sectors = transport_get_sectors_12(cdb);
372 cmd->t_task_lba = transport_lba_32(cdb);
373 if (cdb[1] & 0x8)
374 cmd->se_cmd_flags |= SCF_FUA;
375 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
376 cmd->execute_cmd = ops->execute_rw;
377 break;
378 case WRITE_16:
379 sectors = transport_get_sectors_16(cdb);
380 cmd->t_task_lba = transport_lba_64(cdb);
381 if (cdb[1] & 0x8)
382 cmd->se_cmd_flags |= SCF_FUA;
383 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
384 cmd->execute_cmd = ops->execute_rw;
385 break;
386 case XDWRITEREAD_10:
387 if (cmd->data_direction != DMA_TO_DEVICE ||
388 !(cmd->se_cmd_flags & SCF_BIDI))
389 return TCM_INVALID_CDB_FIELD;
390 sectors = transport_get_sectors_10(cdb);
391
392 cmd->t_task_lba = transport_lba_32(cdb);
393 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
394
395 /*
396 * Setup BIDI XOR callback to be run after I/O completion.
397 */
398 cmd->execute_cmd = ops->execute_rw;
399 cmd->transport_complete_callback = &xdreadwrite_callback;
400 if (cdb[1] & 0x8)
401 cmd->se_cmd_flags |= SCF_FUA;
402 break;
403 case VARIABLE_LENGTH_CMD:
404 {
405 u16 service_action = get_unaligned_be16(&cdb[8]);
406 switch (service_action) {
407 case XDWRITEREAD_32:
408 sectors = transport_get_sectors_32(cdb);
409
410 /*
411 * Use WRITE_32 and READ_32 opcodes for the emulated
412 * XDWRITE_READ_32 logic.
413 */
414 cmd->t_task_lba = transport_lba_64_ext(cdb);
415 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
416
417 /*
418 * Setup BIDI XOR callback to be run during after I/O
419 * completion.
420 */
421 cmd->execute_cmd = ops->execute_rw;
422 cmd->transport_complete_callback = &xdreadwrite_callback;
423 if (cdb[1] & 0x8)
424 cmd->se_cmd_flags |= SCF_FUA;
425 break;
426 case WRITE_SAME_32:
427 sectors = transport_get_sectors_32(cdb);
428 if (!sectors) {
429 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
430 " supported\n");
431 return TCM_INVALID_CDB_FIELD;
432 }
433
434 size = sbc_get_size(cmd, 1);
435 cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
436
437 ret = sbc_setup_write_same(cmd, &cdb[10], ops);
438 if (ret)
439 return ret;
440 break;
441 default:
442 pr_err("VARIABLE_LENGTH_CMD service action"
443 " 0x%04x not supported\n", service_action);
444 return TCM_UNSUPPORTED_SCSI_OPCODE;
445 }
446 break;
447 }
448 case READ_CAPACITY:
449 size = READ_CAP_LEN;
450 cmd->execute_cmd = sbc_emulate_readcapacity;
451 break;
452 case SERVICE_ACTION_IN:
453 switch (cmd->t_task_cdb[1] & 0x1f) {
454 case SAI_READ_CAPACITY_16:
455 cmd->execute_cmd = sbc_emulate_readcapacity_16;
456 break;
457 default:
458 pr_err("Unsupported SA: 0x%02x\n",
459 cmd->t_task_cdb[1] & 0x1f);
460 return TCM_INVALID_CDB_FIELD;
461 }
462 size = (cdb[10] << 24) | (cdb[11] << 16) |
463 (cdb[12] << 8) | cdb[13];
464 break;
465 case SYNCHRONIZE_CACHE:
466 case SYNCHRONIZE_CACHE_16:
467 if (!ops->execute_sync_cache) {
468 size = 0;
469 cmd->execute_cmd = sbc_emulate_noop;
470 break;
471 }
472
473 /*
474 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
475 */
476 if (cdb[0] == SYNCHRONIZE_CACHE) {
477 sectors = transport_get_sectors_10(cdb);
478 cmd->t_task_lba = transport_lba_32(cdb);
479 } else {
480 sectors = transport_get_sectors_16(cdb);
481 cmd->t_task_lba = transport_lba_64(cdb);
482 }
483
484 size = sbc_get_size(cmd, sectors);
485
486 /*
487 * Check to ensure that LBA + Range does not exceed past end of
488 * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
489 */
490 if (cmd->t_task_lba || sectors) {
491 if (sbc_check_valid_sectors(cmd) < 0)
492 return TCM_ADDRESS_OUT_OF_RANGE;
493 }
494 cmd->execute_cmd = ops->execute_sync_cache;
495 break;
496 case UNMAP:
497 if (!ops->execute_unmap)
498 return TCM_UNSUPPORTED_SCSI_OPCODE;
499
500 size = get_unaligned_be16(&cdb[7]);
501 cmd->execute_cmd = ops->execute_unmap;
502 break;
503 case WRITE_SAME_16:
504 sectors = transport_get_sectors_16(cdb);
505 if (!sectors) {
506 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
507 return TCM_INVALID_CDB_FIELD;
508 }
509
510 size = sbc_get_size(cmd, 1);
511 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
512
513 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
514 if (ret)
515 return ret;
516 break;
517 case WRITE_SAME:
518 sectors = transport_get_sectors_10(cdb);
519 if (!sectors) {
520 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
521 return TCM_INVALID_CDB_FIELD;
522 }
523
524 size = sbc_get_size(cmd, 1);
525 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
526
527 /*
528 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
529 * of byte 1 bit 3 UNMAP instead of original reserved field
530 */
531 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
532 if (ret)
533 return ret;
534 break;
535 case VERIFY:
536 size = 0;
537 cmd->execute_cmd = sbc_emulate_noop;
538 break;
539 case REZERO_UNIT:
540 case SEEK_6:
541 case SEEK_10:
542 /*
543 * There are still clients out there which use these old SCSI-2
544 * commands. This mainly happens when running VMs with legacy
545 * guest systems, connected via SCSI command pass-through to
546 * iSCSI targets. Make them happy and return status GOOD.
547 */
548 size = 0;
549 cmd->execute_cmd = sbc_emulate_noop;
550 break;
551 default:
552 ret = spc_parse_cdb(cmd, &size);
553 if (ret)
554 return ret;
555 }
556
557 /* reject any command that we don't have a handler for */
558 if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
559 return TCM_UNSUPPORTED_SCSI_OPCODE;
560
561 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
562 unsigned long long end_lba;
563
564 if (sectors > dev->dev_attrib.fabric_max_sectors) {
565 printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
566 " big sectors %u exceeds fabric_max_sectors:"
567 " %u\n", cdb[0], sectors,
568 dev->dev_attrib.fabric_max_sectors);
569 return TCM_INVALID_CDB_FIELD;
570 }
571 if (sectors > dev->dev_attrib.hw_max_sectors) {
572 printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
573 " big sectors %u exceeds backend hw_max_sectors:"
574 " %u\n", cdb[0], sectors,
575 dev->dev_attrib.hw_max_sectors);
576 return TCM_INVALID_CDB_FIELD;
577 }
578
579 end_lba = dev->transport->get_blocks(dev) + 1;
580 if (cmd->t_task_lba + sectors > end_lba) {
581 pr_err("cmd exceeds last lba %llu "
582 "(lba %llu, sectors %u)\n",
583 end_lba, cmd->t_task_lba, sectors);
584 return TCM_INVALID_CDB_FIELD;
585 }
586
587 size = sbc_get_size(cmd, sectors);
588 }
589
590 return target_cmd_size_check(cmd, size);
591 }
592 EXPORT_SYMBOL(sbc_parse_cdb);
593
sbc_get_device_type(struct se_device * dev)594 u32 sbc_get_device_type(struct se_device *dev)
595 {
596 return TYPE_DISK;
597 }
598 EXPORT_SYMBOL(sbc_get_device_type);
599
600 sense_reason_t
sbc_execute_unmap(struct se_cmd * cmd,sense_reason_t (* do_unmap_fn)(struct se_cmd *,void *,sector_t,sector_t),void * priv)601 sbc_execute_unmap(struct se_cmd *cmd,
602 sense_reason_t (*do_unmap_fn)(struct se_cmd *, void *,
603 sector_t, sector_t),
604 void *priv)
605 {
606 struct se_device *dev = cmd->se_dev;
607 unsigned char *buf, *ptr = NULL;
608 sector_t lba;
609 int size;
610 u32 range;
611 sense_reason_t ret = 0;
612 int dl, bd_dl;
613
614 /* We never set ANC_SUP */
615 if (cmd->t_task_cdb[1])
616 return TCM_INVALID_CDB_FIELD;
617
618 if (cmd->data_length == 0) {
619 target_complete_cmd(cmd, SAM_STAT_GOOD);
620 return 0;
621 }
622
623 if (cmd->data_length < 8) {
624 pr_warn("UNMAP parameter list length %u too small\n",
625 cmd->data_length);
626 return TCM_PARAMETER_LIST_LENGTH_ERROR;
627 }
628
629 buf = transport_kmap_data_sg(cmd);
630 if (!buf)
631 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
632
633 dl = get_unaligned_be16(&buf[0]);
634 bd_dl = get_unaligned_be16(&buf[2]);
635
636 size = cmd->data_length - 8;
637 if (bd_dl > size)
638 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
639 cmd->data_length, bd_dl);
640 else
641 size = bd_dl;
642
643 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
644 ret = TCM_INVALID_PARAMETER_LIST;
645 goto err;
646 }
647
648 /* First UNMAP block descriptor starts at 8 byte offset */
649 ptr = &buf[8];
650 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
651 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
652
653 while (size >= 16) {
654 lba = get_unaligned_be64(&ptr[0]);
655 range = get_unaligned_be32(&ptr[8]);
656 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
657 (unsigned long long)lba, range);
658
659 if (range > dev->dev_attrib.max_unmap_lba_count) {
660 ret = TCM_INVALID_PARAMETER_LIST;
661 goto err;
662 }
663
664 if (lba + range > dev->transport->get_blocks(dev) + 1) {
665 ret = TCM_ADDRESS_OUT_OF_RANGE;
666 goto err;
667 }
668
669 ret = do_unmap_fn(cmd, priv, lba, range);
670 if (ret)
671 goto err;
672
673 ptr += 16;
674 size -= 16;
675 }
676
677 err:
678 transport_kunmap_data_sg(cmd);
679 if (!ret)
680 target_complete_cmd(cmd, GOOD);
681 return ret;
682 }
683 EXPORT_SYMBOL(sbc_execute_unmap);
684