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target: Drop lun_sep_lock for se_lun->lun_se_dev RCU usage
[linux-2.6/btrfs-unstable.git] / drivers / target / target_core_rd.c
blobe98432705f39597edcbce3abbfd6270f0e5daa3c
1 /*******************************************************************************
2 * Filename: target_core_rd.c
3 *
4 * This file contains the Storage Engine <-> Ramdisk transport
5 * specific functions.
6 *
7 * (c) Copyright 2003-2013 Datera, Inc.
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 *
25 ******************************************************************************/
26
27 #include <linux/string.h>
28 #include <linux/parser.h>
29 #include <linux/timer.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <scsi/scsi.h>
33 #include <scsi/scsi_host.h>
34
35 #include <target/target_core_base.h>
36 #include <target/target_core_backend.h>
37
38 #include "target_core_rd.h"
39
40 static inline struct rd_dev *RD_DEV(struct se_device *dev)
41 {
42 return container_of(dev, struct rd_dev, dev);
43 }
44
45 static int rd_attach_hba(struct se_hba *hba, u32 host_id)
46 {
47 struct rd_host *rd_host;
48
49 rd_host = kzalloc(sizeof(struct rd_host), GFP_KERNEL);
50 if (!rd_host) {
51 pr_err("Unable to allocate memory for struct rd_host\n");
52 return -ENOMEM;
53 }
54
55 rd_host->rd_host_id = host_id;
56
57 hba->hba_ptr = rd_host;
58
59 pr_debug("CORE_HBA[%d] - TCM Ramdisk HBA Driver %s on"
60 " Generic Target Core Stack %s\n", hba->hba_id,
61 RD_HBA_VERSION, TARGET_CORE_MOD_VERSION);
62
63 return 0;
64 }
65
66 static void rd_detach_hba(struct se_hba *hba)
67 {
68 struct rd_host *rd_host = hba->hba_ptr;
69
70 pr_debug("CORE_HBA[%d] - Detached Ramdisk HBA: %u from"
71 " Generic Target Core\n", hba->hba_id, rd_host->rd_host_id);
72
73 kfree(rd_host);
74 hba->hba_ptr = NULL;
75 }
76
77 static u32 rd_release_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
78 u32 sg_table_count)
79 {
80 struct page *pg;
81 struct scatterlist *sg;
82 u32 i, j, page_count = 0, sg_per_table;
83
84 for (i = 0; i < sg_table_count; i++) {
85 sg = sg_table[i].sg_table;
86 sg_per_table = sg_table[i].rd_sg_count;
87
88 for (j = 0; j < sg_per_table; j++) {
89 pg = sg_page(&sg[j]);
90 if (pg) {
91 __free_page(pg);
92 page_count++;
93 }
94 }
95 kfree(sg);
96 }
97
98 kfree(sg_table);
99 return page_count;
100 }
101
102 static void rd_release_device_space(struct rd_dev *rd_dev)
103 {
104 u32 page_count;
105
106 if (!rd_dev->sg_table_array || !rd_dev->sg_table_count)
107 return;
108
109 page_count = rd_release_sgl_table(rd_dev, rd_dev->sg_table_array,
110 rd_dev->sg_table_count);
111
112 pr_debug("CORE_RD[%u] - Released device space for Ramdisk"
113 " Device ID: %u, pages %u in %u tables total bytes %lu\n",
114 rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
115 rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
116
117 rd_dev->sg_table_array = NULL;
118 rd_dev->sg_table_count = 0;
119 }
120
121
122 /* rd_build_device_space():
123 *
124 *
125 */
126 static int rd_allocate_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
127 u32 total_sg_needed, unsigned char init_payload)
128 {
129 u32 i = 0, j, page_offset = 0, sg_per_table;
130 u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
131 sizeof(struct scatterlist));
132 struct page *pg;
133 struct scatterlist *sg;
134 unsigned char *p;
135
136 while (total_sg_needed) {
137 unsigned int chain_entry = 0;
138
139 sg_per_table = (total_sg_needed > max_sg_per_table) ?
140 max_sg_per_table : total_sg_needed;
141
142 #ifdef CONFIG_ARCH_HAS_SG_CHAIN
143
144 /*
145 * Reserve extra element for chain entry
146 */
147 if (sg_per_table < total_sg_needed)
148 chain_entry = 1;
149
150 #endif /* CONFIG_ARCH_HAS_SG_CHAIN */
151
152 sg = kcalloc(sg_per_table + chain_entry, sizeof(*sg),
153 GFP_KERNEL);
154 if (!sg) {
155 pr_err("Unable to allocate scatterlist array"
156 " for struct rd_dev\n");
157 return -ENOMEM;
158 }
159
160 sg_init_table(sg, sg_per_table + chain_entry);
161
162 #ifdef CONFIG_ARCH_HAS_SG_CHAIN
163
164 if (i > 0) {
165 sg_chain(sg_table[i - 1].sg_table,
166 max_sg_per_table + 1, sg);
167 }
168
169 #endif /* CONFIG_ARCH_HAS_SG_CHAIN */
170
171 sg_table[i].sg_table = sg;
172 sg_table[i].rd_sg_count = sg_per_table;
173 sg_table[i].page_start_offset = page_offset;
174 sg_table[i++].page_end_offset = (page_offset + sg_per_table)
175 - 1;
176
177 for (j = 0; j < sg_per_table; j++) {
178 pg = alloc_pages(GFP_KERNEL, 0);
179 if (!pg) {
180 pr_err("Unable to allocate scatterlist"
181 " pages for struct rd_dev_sg_table\n");
182 return -ENOMEM;
183 }
184 sg_assign_page(&sg[j], pg);
185 sg[j].length = PAGE_SIZE;
186
187 p = kmap(pg);
188 memset(p, init_payload, PAGE_SIZE);
189 kunmap(pg);
190 }
191
192 page_offset += sg_per_table;
193 total_sg_needed -= sg_per_table;
194 }
195
196 return 0;
197 }
198
199 static int rd_build_device_space(struct rd_dev *rd_dev)
200 {
201 struct rd_dev_sg_table *sg_table;
202 u32 sg_tables, total_sg_needed;
203 u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
204 sizeof(struct scatterlist));
205 int rc;
206
207 if (rd_dev->rd_page_count <= 0) {
208 pr_err("Illegal page count: %u for Ramdisk device\n",
209 rd_dev->rd_page_count);
210 return -EINVAL;
211 }
212
213 /* Don't need backing pages for NULLIO */
214 if (rd_dev->rd_flags & RDF_NULLIO)
215 return 0;
216
217 total_sg_needed = rd_dev->rd_page_count;
218
219 sg_tables = (total_sg_needed / max_sg_per_table) + 1;
220
221 sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
222 if (!sg_table) {
223 pr_err("Unable to allocate memory for Ramdisk"
224 " scatterlist tables\n");
225 return -ENOMEM;
226 }
227
228 rd_dev->sg_table_array = sg_table;
229 rd_dev->sg_table_count = sg_tables;
230
231 rc = rd_allocate_sgl_table(rd_dev, sg_table, total_sg_needed, 0x00);
232 if (rc)
233 return rc;
234
235 pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u space of"
236 " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
237 rd_dev->rd_dev_id, rd_dev->rd_page_count,
238 rd_dev->sg_table_count);
239
240 return 0;
241 }
242
243 static void rd_release_prot_space(struct rd_dev *rd_dev)
244 {
245 u32 page_count;
246
247 if (!rd_dev->sg_prot_array || !rd_dev->sg_prot_count)
248 return;
249
250 page_count = rd_release_sgl_table(rd_dev, rd_dev->sg_prot_array,
251 rd_dev->sg_prot_count);
252
253 pr_debug("CORE_RD[%u] - Released protection space for Ramdisk"
254 " Device ID: %u, pages %u in %u tables total bytes %lu\n",
255 rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
256 rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
257
258 rd_dev->sg_prot_array = NULL;
259 rd_dev->sg_prot_count = 0;
260 }
261
262 static int rd_build_prot_space(struct rd_dev *rd_dev, int prot_length, int block_size)
263 {
264 struct rd_dev_sg_table *sg_table;
265 u32 total_sg_needed, sg_tables;
266 u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
267 sizeof(struct scatterlist));
268 int rc;
269
270 if (rd_dev->rd_flags & RDF_NULLIO)
271 return 0;
272 /*
273 * prot_length=8byte dif data
274 * tot sg needed = rd_page_count * (PGSZ/block_size) *
275 * (prot_length/block_size) + pad
276 * PGSZ canceled each other.
277 */
278 total_sg_needed = (rd_dev->rd_page_count * prot_length / block_size) + 1;
279
280 sg_tables = (total_sg_needed / max_sg_per_table) + 1;
281
282 sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
283 if (!sg_table) {
284 pr_err("Unable to allocate memory for Ramdisk protection"
285 " scatterlist tables\n");
286 return -ENOMEM;
287 }
288
289 rd_dev->sg_prot_array = sg_table;
290 rd_dev->sg_prot_count = sg_tables;
291
292 rc = rd_allocate_sgl_table(rd_dev, sg_table, total_sg_needed, 0xff);
293 if (rc)
294 return rc;
295
296 pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u prot space of"
297 " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
298 rd_dev->rd_dev_id, total_sg_needed, rd_dev->sg_prot_count);
299
300 return 0;
301 }
302
303 static struct se_device *rd_alloc_device(struct se_hba *hba, const char *name)
304 {
305 struct rd_dev *rd_dev;
306 struct rd_host *rd_host = hba->hba_ptr;
307
308 rd_dev = kzalloc(sizeof(struct rd_dev), GFP_KERNEL);
309 if (!rd_dev) {
310 pr_err("Unable to allocate memory for struct rd_dev\n");
311 return NULL;
312 }
313
314 rd_dev->rd_host = rd_host;
315
316 return &rd_dev->dev;
317 }
318
319 static int rd_configure_device(struct se_device *dev)
320 {
321 struct rd_dev *rd_dev = RD_DEV(dev);
322 struct rd_host *rd_host = dev->se_hba->hba_ptr;
323 int ret;
324
325 if (!(rd_dev->rd_flags & RDF_HAS_PAGE_COUNT)) {
326 pr_debug("Missing rd_pages= parameter\n");
327 return -EINVAL;
328 }
329
330 ret = rd_build_device_space(rd_dev);
331 if (ret < 0)
332 goto fail;
333
334 dev->dev_attrib.hw_block_size = RD_BLOCKSIZE;
335 dev->dev_attrib.hw_max_sectors = UINT_MAX;
336 dev->dev_attrib.hw_queue_depth = RD_MAX_DEVICE_QUEUE_DEPTH;
337
338 rd_dev->rd_dev_id = rd_host->rd_host_dev_id_count++;
339
340 pr_debug("CORE_RD[%u] - Added TCM MEMCPY Ramdisk Device ID: %u of"
341 " %u pages in %u tables, %lu total bytes\n",
342 rd_host->rd_host_id, rd_dev->rd_dev_id, rd_dev->rd_page_count,
343 rd_dev->sg_table_count,
344 (unsigned long)(rd_dev->rd_page_count * PAGE_SIZE));
345
346 return 0;
347
348 fail:
349 rd_release_device_space(rd_dev);
350 return ret;
351 }
352
353 static void rd_dev_call_rcu(struct rcu_head *p)
354 {
355 struct se_device *dev = container_of(p, struct se_device, rcu_head);
356 struct rd_dev *rd_dev = RD_DEV(dev);
357
358 kfree(rd_dev);
359 }
360
361 static void rd_free_device(struct se_device *dev)
362 {
363 struct rd_dev *rd_dev = RD_DEV(dev);
364
365 rd_release_device_space(rd_dev);
366 call_rcu(&dev->rcu_head, rd_dev_call_rcu);
367 }
368
369 static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page)
370 {
371 struct rd_dev_sg_table *sg_table;
372 u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE /
373 sizeof(struct scatterlist));
374
375 i = page / sg_per_table;
376 if (i < rd_dev->sg_table_count) {
377 sg_table = &rd_dev->sg_table_array[i];
378 if ((sg_table->page_start_offset <= page) &&
379 (sg_table->page_end_offset >= page))
380 return sg_table;
381 }
382
383 pr_err("Unable to locate struct rd_dev_sg_table for page: %u\n",
384 page);
385
386 return NULL;
387 }
388
389 static struct rd_dev_sg_table *rd_get_prot_table(struct rd_dev *rd_dev, u32 page)
390 {
391 struct rd_dev_sg_table *sg_table;
392 u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE /
393 sizeof(struct scatterlist));
394
395 i = page / sg_per_table;
396 if (i < rd_dev->sg_prot_count) {
397 sg_table = &rd_dev->sg_prot_array[i];
398 if ((sg_table->page_start_offset <= page) &&
399 (sg_table->page_end_offset >= page))
400 return sg_table;
401 }
402
403 pr_err("Unable to locate struct prot rd_dev_sg_table for page: %u\n",
404 page);
405
406 return NULL;
407 }
408
409 static sense_reason_t rd_do_prot_rw(struct se_cmd *cmd, bool is_read)
410 {
411 struct se_device *se_dev = cmd->se_dev;
412 struct rd_dev *dev = RD_DEV(se_dev);
413 struct rd_dev_sg_table *prot_table;
414 bool need_to_release = false;
415 struct scatterlist *prot_sg;
416 u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
417 u32 prot_offset, prot_page;
418 u32 prot_npages __maybe_unused;
419 u64 tmp;
420 sense_reason_t rc = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
421
422 tmp = cmd->t_task_lba * se_dev->prot_length;
423 prot_offset = do_div(tmp, PAGE_SIZE);
424 prot_page = tmp;
425
426 prot_table = rd_get_prot_table(dev, prot_page);
427 if (!prot_table)
428 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
429
430 prot_sg = &prot_table->sg_table[prot_page -
431 prot_table->page_start_offset];
432
433 #ifndef CONFIG_ARCH_HAS_SG_CHAIN
434
435 prot_npages = DIV_ROUND_UP(prot_offset + sectors * se_dev->prot_length,
436 PAGE_SIZE);
437
438 /*
439 * Allocate temporaly contiguous scatterlist entries if prot pages
440 * straddles multiple scatterlist tables.
441 */
442 if (prot_table->page_end_offset < prot_page + prot_npages - 1) {
443 int i;
444
445 prot_sg = kcalloc(prot_npages, sizeof(*prot_sg), GFP_KERNEL);
446 if (!prot_sg)
447 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
448
449 need_to_release = true;
450 sg_init_table(prot_sg, prot_npages);
451
452 for (i = 0; i < prot_npages; i++) {
453 if (prot_page + i > prot_table->page_end_offset) {
454 prot_table = rd_get_prot_table(dev,
455 prot_page + i);
456 if (!prot_table) {
457 kfree(prot_sg);
458 return rc;
459 }
460 sg_unmark_end(&prot_sg[i - 1]);
461 }
462 prot_sg[i] = prot_table->sg_table[prot_page + i -
463 prot_table->page_start_offset];
464 }
465 }
466
467 #endif /* !CONFIG_ARCH_HAS_SG_CHAIN */
468
469 if (is_read)
470 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 0,
471 prot_sg, prot_offset);
472 else
473 rc = sbc_dif_verify(cmd, cmd->t_task_lba, sectors, 0,
474 cmd->t_prot_sg, 0);
475
476 if (!rc)
477 sbc_dif_copy_prot(cmd, sectors, is_read, prot_sg, prot_offset);
478
479 if (need_to_release)
480 kfree(prot_sg);
481
482 return rc;
483 }
484
485 static sense_reason_t
486 rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
487 enum dma_data_direction data_direction)
488 {
489 struct se_device *se_dev = cmd->se_dev;
490 struct rd_dev *dev = RD_DEV(se_dev);
491 struct rd_dev_sg_table *table;
492 struct scatterlist *rd_sg;
493 struct sg_mapping_iter m;
494 u32 rd_offset;
495 u32 rd_size;
496 u32 rd_page;
497 u32 src_len;
498 u64 tmp;
499 sense_reason_t rc;
500
501 if (dev->rd_flags & RDF_NULLIO) {
502 target_complete_cmd(cmd, SAM_STAT_GOOD);
503 return 0;
504 }
505
506 tmp = cmd->t_task_lba * se_dev->dev_attrib.block_size;
507 rd_offset = do_div(tmp, PAGE_SIZE);
508 rd_page = tmp;
509 rd_size = cmd->data_length;
510
511 table = rd_get_sg_table(dev, rd_page);
512 if (!table)
513 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
514
515 rd_sg = &table->sg_table[rd_page - table->page_start_offset];
516
517 pr_debug("RD[%u]: %s LBA: %llu, Size: %u Page: %u, Offset: %u\n",
518 dev->rd_dev_id,
519 data_direction == DMA_FROM_DEVICE ? "Read" : "Write",
520 cmd->t_task_lba, rd_size, rd_page, rd_offset);
521
522 if (cmd->prot_type && se_dev->dev_attrib.pi_prot_type &&
523 data_direction == DMA_TO_DEVICE) {
524 rc = rd_do_prot_rw(cmd, false);
525 if (rc)
526 return rc;
527 }
528
529 src_len = PAGE_SIZE - rd_offset;
530 sg_miter_start(&m, sgl, sgl_nents,
531 data_direction == DMA_FROM_DEVICE ?
532 SG_MITER_TO_SG : SG_MITER_FROM_SG);
533 while (rd_size) {
534 u32 len;
535 void *rd_addr;
536
537 sg_miter_next(&m);
538 if (!(u32)m.length) {
539 pr_debug("RD[%u]: invalid sgl %p len %zu\n",
540 dev->rd_dev_id, m.addr, m.length);
541 sg_miter_stop(&m);
542 return TCM_INCORRECT_AMOUNT_OF_DATA;
543 }
544 len = min((u32)m.length, src_len);
545 if (len > rd_size) {
546 pr_debug("RD[%u]: size underrun page %d offset %d "
547 "size %d\n", dev->rd_dev_id,
548 rd_page, rd_offset, rd_size);
549 len = rd_size;
550 }
551 m.consumed = len;
552
553 rd_addr = sg_virt(rd_sg) + rd_offset;
554
555 if (data_direction == DMA_FROM_DEVICE)
556 memcpy(m.addr, rd_addr, len);
557 else
558 memcpy(rd_addr, m.addr, len);
559
560 rd_size -= len;
561 if (!rd_size)
562 continue;
563
564 src_len -= len;
565 if (src_len) {
566 rd_offset += len;
567 continue;
568 }
569
570 /* rd page completed, next one please */
571 rd_page++;
572 rd_offset = 0;
573 src_len = PAGE_SIZE;
574 if (rd_page <= table->page_end_offset) {
575 rd_sg++;
576 continue;
577 }
578
579 table = rd_get_sg_table(dev, rd_page);
580 if (!table) {
581 sg_miter_stop(&m);
582 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
583 }
584
585 /* since we increment, the first sg entry is correct */
586 rd_sg = table->sg_table;
587 }
588 sg_miter_stop(&m);
589
590 if (cmd->prot_type && se_dev->dev_attrib.pi_prot_type &&
591 data_direction == DMA_FROM_DEVICE) {
592 rc = rd_do_prot_rw(cmd, true);
593 if (rc)
594 return rc;
595 }
596
597 target_complete_cmd(cmd, SAM_STAT_GOOD);
598 return 0;
599 }
600
601 enum {
602 Opt_rd_pages, Opt_rd_nullio, Opt_err
603 };
604
605 static match_table_t tokens = {
606 {Opt_rd_pages, "rd_pages=%d"},
607 {Opt_rd_nullio, "rd_nullio=%d"},
608 {Opt_err, NULL}
609 };
610
611 static ssize_t rd_set_configfs_dev_params(struct se_device *dev,
612 const char *page, ssize_t count)
613 {
614 struct rd_dev *rd_dev = RD_DEV(dev);
615 char *orig, *ptr, *opts;
616 substring_t args[MAX_OPT_ARGS];
617 int ret = 0, arg, token;
618
619 opts = kstrdup(page, GFP_KERNEL);
620 if (!opts)
621 return -ENOMEM;
622
623 orig = opts;
624
625 while ((ptr = strsep(&opts, ",\n")) != NULL) {
626 if (!*ptr)
627 continue;
628
629 token = match_token(ptr, tokens, args);
630 switch (token) {
631 case Opt_rd_pages:
632 match_int(args, &arg);
633 rd_dev->rd_page_count = arg;
634 pr_debug("RAMDISK: Referencing Page"
635 " Count: %u\n", rd_dev->rd_page_count);
636 rd_dev->rd_flags |= RDF_HAS_PAGE_COUNT;
637 break;
638 case Opt_rd_nullio:
639 match_int(args, &arg);
640 if (arg != 1)
641 break;
642
643 pr_debug("RAMDISK: Setting NULLIO flag: %d\n", arg);
644 rd_dev->rd_flags |= RDF_NULLIO;
645 break;
646 default:
647 break;
648 }
649 }
650
651 kfree(orig);
652 return (!ret) ? count : ret;
653 }
654
655 static ssize_t rd_show_configfs_dev_params(struct se_device *dev, char *b)
656 {
657 struct rd_dev *rd_dev = RD_DEV(dev);
658
659 ssize_t bl = sprintf(b, "TCM RamDisk ID: %u RamDisk Makeup: rd_mcp\n",
660 rd_dev->rd_dev_id);
661 bl += sprintf(b + bl, " PAGES/PAGE_SIZE: %u*%lu"
662 " SG_table_count: %u nullio: %d\n", rd_dev->rd_page_count,
663 PAGE_SIZE, rd_dev->sg_table_count,
664 !!(rd_dev->rd_flags & RDF_NULLIO));
665 return bl;
666 }
667
668 static sector_t rd_get_blocks(struct se_device *dev)
669 {
670 struct rd_dev *rd_dev = RD_DEV(dev);
671
672 unsigned long long blocks_long = ((rd_dev->rd_page_count * PAGE_SIZE) /
673 dev->dev_attrib.block_size) - 1;
674
675 return blocks_long;
676 }
677
678 static int rd_init_prot(struct se_device *dev)
679 {
680 struct rd_dev *rd_dev = RD_DEV(dev);
681
682 if (!dev->dev_attrib.pi_prot_type)
683 return 0;
684
685 return rd_build_prot_space(rd_dev, dev->prot_length,
686 dev->dev_attrib.block_size);
687 }
688
689 static void rd_free_prot(struct se_device *dev)
690 {
691 struct rd_dev *rd_dev = RD_DEV(dev);
692
693 rd_release_prot_space(rd_dev);
694 }
695
696 static struct sbc_ops rd_sbc_ops = {
697 .execute_rw = rd_execute_rw,
698 };
699
700 static sense_reason_t
701 rd_parse_cdb(struct se_cmd *cmd)
702 {
703 return sbc_parse_cdb(cmd, &rd_sbc_ops);
704 }
705
706 static const struct target_backend_ops rd_mcp_ops = {
707 .name = "rd_mcp",
708 .inquiry_prod = "RAMDISK-MCP",
709 .inquiry_rev = RD_MCP_VERSION,
710 .attach_hba = rd_attach_hba,
711 .detach_hba = rd_detach_hba,
712 .alloc_device = rd_alloc_device,
713 .configure_device = rd_configure_device,
714 .free_device = rd_free_device,
715 .parse_cdb = rd_parse_cdb,
716 .set_configfs_dev_params = rd_set_configfs_dev_params,
717 .show_configfs_dev_params = rd_show_configfs_dev_params,
718 .get_device_type = sbc_get_device_type,
719 .get_blocks = rd_get_blocks,
720 .init_prot = rd_init_prot,
721 .free_prot = rd_free_prot,
722 .tb_dev_attrib_attrs = sbc_attrib_attrs,
723 };
724
725 int __init rd_module_init(void)
726 {
727 return transport_backend_register(&rd_mcp_ops);
728 }
729
730 void rd_module_exit(void)
731 {
732 target_backend_unregister(&rd_mcp_ops);
733 }
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