xref: /linux/drivers/target/target_core_rd.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
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 #include <target/target_core_backend_configfs.h>
38 
39 #include "target_core_rd.h"
40 
41 static inline struct rd_dev *RD_DEV(struct se_device *dev)
42 {
43 	return container_of(dev, struct rd_dev, dev);
44 }
45 
46 /*	rd_attach_hba(): (Part of se_subsystem_api_t template)
47  *
48  *
49  */
50 static int rd_attach_hba(struct se_hba *hba, u32 host_id)
51 {
52 	struct rd_host *rd_host;
53 
54 	rd_host = kzalloc(sizeof(struct rd_host), GFP_KERNEL);
55 	if (!rd_host) {
56 		pr_err("Unable to allocate memory for struct rd_host\n");
57 		return -ENOMEM;
58 	}
59 
60 	rd_host->rd_host_id = host_id;
61 
62 	hba->hba_ptr = rd_host;
63 
64 	pr_debug("CORE_HBA[%d] - TCM Ramdisk HBA Driver %s on"
65 		" Generic Target Core Stack %s\n", hba->hba_id,
66 		RD_HBA_VERSION, TARGET_CORE_MOD_VERSION);
67 
68 	return 0;
69 }
70 
71 static void rd_detach_hba(struct se_hba *hba)
72 {
73 	struct rd_host *rd_host = hba->hba_ptr;
74 
75 	pr_debug("CORE_HBA[%d] - Detached Ramdisk HBA: %u from"
76 		" Generic Target Core\n", hba->hba_id, rd_host->rd_host_id);
77 
78 	kfree(rd_host);
79 	hba->hba_ptr = NULL;
80 }
81 
82 static u32 rd_release_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
83 				 u32 sg_table_count)
84 {
85 	struct page *pg;
86 	struct scatterlist *sg;
87 	u32 i, j, page_count = 0, sg_per_table;
88 
89 	for (i = 0; i < sg_table_count; i++) {
90 		sg = sg_table[i].sg_table;
91 		sg_per_table = sg_table[i].rd_sg_count;
92 
93 		for (j = 0; j < sg_per_table; j++) {
94 			pg = sg_page(&sg[j]);
95 			if (pg) {
96 				__free_page(pg);
97 				page_count++;
98 			}
99 		}
100 		kfree(sg);
101 	}
102 
103 	kfree(sg_table);
104 	return page_count;
105 }
106 
107 static void rd_release_device_space(struct rd_dev *rd_dev)
108 {
109 	u32 page_count;
110 
111 	if (!rd_dev->sg_table_array || !rd_dev->sg_table_count)
112 		return;
113 
114 	page_count = rd_release_sgl_table(rd_dev, rd_dev->sg_table_array,
115 					  rd_dev->sg_table_count);
116 
117 	pr_debug("CORE_RD[%u] - Released device space for Ramdisk"
118 		" Device ID: %u, pages %u in %u tables total bytes %lu\n",
119 		rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
120 		rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
121 
122 	rd_dev->sg_table_array = NULL;
123 	rd_dev->sg_table_count = 0;
124 }
125 
126 
127 /*	rd_build_device_space():
128  *
129  *
130  */
131 static int rd_allocate_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
132 				 u32 total_sg_needed, unsigned char init_payload)
133 {
134 	u32 i = 0, j, page_offset = 0, sg_per_table;
135 	u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
136 				sizeof(struct scatterlist));
137 	struct page *pg;
138 	struct scatterlist *sg;
139 	unsigned char *p;
140 
141 	while (total_sg_needed) {
142 		sg_per_table = (total_sg_needed > max_sg_per_table) ?
143 			max_sg_per_table : total_sg_needed;
144 
145 		sg = kzalloc(sg_per_table * sizeof(struct scatterlist),
146 				GFP_KERNEL);
147 		if (!sg) {
148 			pr_err("Unable to allocate scatterlist array"
149 				" for struct rd_dev\n");
150 			return -ENOMEM;
151 		}
152 
153 		sg_init_table(sg, sg_per_table);
154 
155 		sg_table[i].sg_table = sg;
156 		sg_table[i].rd_sg_count = sg_per_table;
157 		sg_table[i].page_start_offset = page_offset;
158 		sg_table[i++].page_end_offset = (page_offset + sg_per_table)
159 						- 1;
160 
161 		for (j = 0; j < sg_per_table; j++) {
162 			pg = alloc_pages(GFP_KERNEL, 0);
163 			if (!pg) {
164 				pr_err("Unable to allocate scatterlist"
165 					" pages for struct rd_dev_sg_table\n");
166 				return -ENOMEM;
167 			}
168 			sg_assign_page(&sg[j], pg);
169 			sg[j].length = PAGE_SIZE;
170 
171 			p = kmap(pg);
172 			memset(p, init_payload, PAGE_SIZE);
173 			kunmap(pg);
174 		}
175 
176 		page_offset += sg_per_table;
177 		total_sg_needed -= sg_per_table;
178 	}
179 
180 	return 0;
181 }
182 
183 static int rd_build_device_space(struct rd_dev *rd_dev)
184 {
185 	struct rd_dev_sg_table *sg_table;
186 	u32 sg_tables, total_sg_needed;
187 	u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
188 				sizeof(struct scatterlist));
189 	int rc;
190 
191 	if (rd_dev->rd_page_count <= 0) {
192 		pr_err("Illegal page count: %u for Ramdisk device\n",
193 		       rd_dev->rd_page_count);
194 		return -EINVAL;
195 	}
196 
197 	/* Don't need backing pages for NULLIO */
198 	if (rd_dev->rd_flags & RDF_NULLIO)
199 		return 0;
200 
201 	total_sg_needed = rd_dev->rd_page_count;
202 
203 	sg_tables = (total_sg_needed / max_sg_per_table) + 1;
204 
205 	sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
206 	if (!sg_table) {
207 		pr_err("Unable to allocate memory for Ramdisk"
208 		       " scatterlist tables\n");
209 		return -ENOMEM;
210 	}
211 
212 	rd_dev->sg_table_array = sg_table;
213 	rd_dev->sg_table_count = sg_tables;
214 
215 	rc = rd_allocate_sgl_table(rd_dev, sg_table, total_sg_needed, 0x00);
216 	if (rc)
217 		return rc;
218 
219 	pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u space of"
220 		 " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
221 		 rd_dev->rd_dev_id, rd_dev->rd_page_count,
222 		 rd_dev->sg_table_count);
223 
224 	return 0;
225 }
226 
227 static void rd_release_prot_space(struct rd_dev *rd_dev)
228 {
229 	u32 page_count;
230 
231 	if (!rd_dev->sg_prot_array || !rd_dev->sg_prot_count)
232 		return;
233 
234 	page_count = rd_release_sgl_table(rd_dev, rd_dev->sg_prot_array,
235 					  rd_dev->sg_prot_count);
236 
237 	pr_debug("CORE_RD[%u] - Released protection space for Ramdisk"
238 		 " Device ID: %u, pages %u in %u tables total bytes %lu\n",
239 		 rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count,
240 		 rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE);
241 
242 	rd_dev->sg_prot_array = NULL;
243 	rd_dev->sg_prot_count = 0;
244 }
245 
246 static int rd_build_prot_space(struct rd_dev *rd_dev, int prot_length, int block_size)
247 {
248 	struct rd_dev_sg_table *sg_table;
249 	u32 total_sg_needed, sg_tables;
250 	u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
251 				sizeof(struct scatterlist));
252 	int rc;
253 
254 	if (rd_dev->rd_flags & RDF_NULLIO)
255 		return 0;
256 	/*
257 	 * prot_length=8byte dif data
258 	 * tot sg needed = rd_page_count * (PGSZ/block_size) *
259 	 * 		   (prot_length/block_size) + pad
260 	 * PGSZ canceled each other.
261 	 */
262 	total_sg_needed = (rd_dev->rd_page_count * prot_length / block_size) + 1;
263 
264 	sg_tables = (total_sg_needed / max_sg_per_table) + 1;
265 
266 	sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
267 	if (!sg_table) {
268 		pr_err("Unable to allocate memory for Ramdisk protection"
269 		       " scatterlist tables\n");
270 		return -ENOMEM;
271 	}
272 
273 	rd_dev->sg_prot_array = sg_table;
274 	rd_dev->sg_prot_count = sg_tables;
275 
276 	rc = rd_allocate_sgl_table(rd_dev, sg_table, total_sg_needed, 0xff);
277 	if (rc)
278 		return rc;
279 
280 	pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u prot space of"
281 		 " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
282 		 rd_dev->rd_dev_id, total_sg_needed, rd_dev->sg_prot_count);
283 
284 	return 0;
285 }
286 
287 static struct se_device *rd_alloc_device(struct se_hba *hba, const char *name)
288 {
289 	struct rd_dev *rd_dev;
290 	struct rd_host *rd_host = hba->hba_ptr;
291 
292 	rd_dev = kzalloc(sizeof(struct rd_dev), GFP_KERNEL);
293 	if (!rd_dev) {
294 		pr_err("Unable to allocate memory for struct rd_dev\n");
295 		return NULL;
296 	}
297 
298 	rd_dev->rd_host = rd_host;
299 
300 	return &rd_dev->dev;
301 }
302 
303 static int rd_configure_device(struct se_device *dev)
304 {
305 	struct rd_dev *rd_dev = RD_DEV(dev);
306 	struct rd_host *rd_host = dev->se_hba->hba_ptr;
307 	int ret;
308 
309 	if (!(rd_dev->rd_flags & RDF_HAS_PAGE_COUNT)) {
310 		pr_debug("Missing rd_pages= parameter\n");
311 		return -EINVAL;
312 	}
313 
314 	ret = rd_build_device_space(rd_dev);
315 	if (ret < 0)
316 		goto fail;
317 
318 	dev->dev_attrib.hw_block_size = RD_BLOCKSIZE;
319 	dev->dev_attrib.hw_max_sectors = UINT_MAX;
320 	dev->dev_attrib.hw_queue_depth = RD_MAX_DEVICE_QUEUE_DEPTH;
321 
322 	rd_dev->rd_dev_id = rd_host->rd_host_dev_id_count++;
323 
324 	pr_debug("CORE_RD[%u] - Added TCM MEMCPY Ramdisk Device ID: %u of"
325 		" %u pages in %u tables, %lu total bytes\n",
326 		rd_host->rd_host_id, rd_dev->rd_dev_id, rd_dev->rd_page_count,
327 		rd_dev->sg_table_count,
328 		(unsigned long)(rd_dev->rd_page_count * PAGE_SIZE));
329 
330 	return 0;
331 
332 fail:
333 	rd_release_device_space(rd_dev);
334 	return ret;
335 }
336 
337 static void rd_free_device(struct se_device *dev)
338 {
339 	struct rd_dev *rd_dev = RD_DEV(dev);
340 
341 	rd_release_device_space(rd_dev);
342 	kfree(rd_dev);
343 }
344 
345 static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page)
346 {
347 	struct rd_dev_sg_table *sg_table;
348 	u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE /
349 				sizeof(struct scatterlist));
350 
351 	i = page / sg_per_table;
352 	if (i < rd_dev->sg_table_count) {
353 		sg_table = &rd_dev->sg_table_array[i];
354 		if ((sg_table->page_start_offset <= page) &&
355 		    (sg_table->page_end_offset >= page))
356 			return sg_table;
357 	}
358 
359 	pr_err("Unable to locate struct rd_dev_sg_table for page: %u\n",
360 			page);
361 
362 	return NULL;
363 }
364 
365 static struct rd_dev_sg_table *rd_get_prot_table(struct rd_dev *rd_dev, u32 page)
366 {
367 	struct rd_dev_sg_table *sg_table;
368 	u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE /
369 				sizeof(struct scatterlist));
370 
371 	i = page / sg_per_table;
372 	if (i < rd_dev->sg_prot_count) {
373 		sg_table = &rd_dev->sg_prot_array[i];
374 		if ((sg_table->page_start_offset <= page) &&
375 		     (sg_table->page_end_offset >= page))
376 			return sg_table;
377 	}
378 
379 	pr_err("Unable to locate struct prot rd_dev_sg_table for page: %u\n",
380 			page);
381 
382 	return NULL;
383 }
384 
385 static sense_reason_t
386 rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
387 	      enum dma_data_direction data_direction)
388 {
389 	struct se_device *se_dev = cmd->se_dev;
390 	struct rd_dev *dev = RD_DEV(se_dev);
391 	struct rd_dev_sg_table *table;
392 	struct scatterlist *rd_sg;
393 	struct sg_mapping_iter m;
394 	u32 rd_offset;
395 	u32 rd_size;
396 	u32 rd_page;
397 	u32 src_len;
398 	u64 tmp;
399 	sense_reason_t rc;
400 
401 	if (dev->rd_flags & RDF_NULLIO) {
402 		target_complete_cmd(cmd, SAM_STAT_GOOD);
403 		return 0;
404 	}
405 
406 	tmp = cmd->t_task_lba * se_dev->dev_attrib.block_size;
407 	rd_offset = do_div(tmp, PAGE_SIZE);
408 	rd_page = tmp;
409 	rd_size = cmd->data_length;
410 
411 	table = rd_get_sg_table(dev, rd_page);
412 	if (!table)
413 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
414 
415 	rd_sg = &table->sg_table[rd_page - table->page_start_offset];
416 
417 	pr_debug("RD[%u]: %s LBA: %llu, Size: %u Page: %u, Offset: %u\n",
418 			dev->rd_dev_id,
419 			data_direction == DMA_FROM_DEVICE ? "Read" : "Write",
420 			cmd->t_task_lba, rd_size, rd_page, rd_offset);
421 
422 	if (cmd->prot_type && data_direction == DMA_TO_DEVICE) {
423 		struct rd_dev_sg_table *prot_table;
424 		struct scatterlist *prot_sg;
425 		u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
426 		u32 prot_offset, prot_page;
427 
428 		tmp = cmd->t_task_lba * se_dev->prot_length;
429 		prot_offset = do_div(tmp, PAGE_SIZE);
430 		prot_page = tmp;
431 
432 		prot_table = rd_get_prot_table(dev, prot_page);
433 		if (!prot_table)
434 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
435 
436 		prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset];
437 
438 		rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors, 0,
439 					  prot_sg, prot_offset);
440 		if (rc)
441 			return rc;
442 	}
443 
444 	src_len = PAGE_SIZE - rd_offset;
445 	sg_miter_start(&m, sgl, sgl_nents,
446 			data_direction == DMA_FROM_DEVICE ?
447 				SG_MITER_TO_SG : SG_MITER_FROM_SG);
448 	while (rd_size) {
449 		u32 len;
450 		void *rd_addr;
451 
452 		sg_miter_next(&m);
453 		if (!(u32)m.length) {
454 			pr_debug("RD[%u]: invalid sgl %p len %zu\n",
455 				 dev->rd_dev_id, m.addr, m.length);
456 			sg_miter_stop(&m);
457 			return TCM_INCORRECT_AMOUNT_OF_DATA;
458 		}
459 		len = min((u32)m.length, src_len);
460 		if (len > rd_size) {
461 			pr_debug("RD[%u]: size underrun page %d offset %d "
462 				 "size %d\n", dev->rd_dev_id,
463 				 rd_page, rd_offset, rd_size);
464 			len = rd_size;
465 		}
466 		m.consumed = len;
467 
468 		rd_addr = sg_virt(rd_sg) + rd_offset;
469 
470 		if (data_direction == DMA_FROM_DEVICE)
471 			memcpy(m.addr, rd_addr, len);
472 		else
473 			memcpy(rd_addr, m.addr, len);
474 
475 		rd_size -= len;
476 		if (!rd_size)
477 			continue;
478 
479 		src_len -= len;
480 		if (src_len) {
481 			rd_offset += len;
482 			continue;
483 		}
484 
485 		/* rd page completed, next one please */
486 		rd_page++;
487 		rd_offset = 0;
488 		src_len = PAGE_SIZE;
489 		if (rd_page <= table->page_end_offset) {
490 			rd_sg++;
491 			continue;
492 		}
493 
494 		table = rd_get_sg_table(dev, rd_page);
495 		if (!table) {
496 			sg_miter_stop(&m);
497 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
498 		}
499 
500 		/* since we increment, the first sg entry is correct */
501 		rd_sg = table->sg_table;
502 	}
503 	sg_miter_stop(&m);
504 
505 	if (cmd->prot_type && data_direction == DMA_FROM_DEVICE) {
506 		struct rd_dev_sg_table *prot_table;
507 		struct scatterlist *prot_sg;
508 		u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
509 		u32 prot_offset, prot_page;
510 
511 		tmp = cmd->t_task_lba * se_dev->prot_length;
512 		prot_offset = do_div(tmp, PAGE_SIZE);
513 		prot_page = tmp;
514 
515 		prot_table = rd_get_prot_table(dev, prot_page);
516 		if (!prot_table)
517 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
518 
519 		prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset];
520 
521 		rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0,
522 					 prot_sg, prot_offset);
523 		if (rc)
524 			return rc;
525 	}
526 
527 	target_complete_cmd(cmd, SAM_STAT_GOOD);
528 	return 0;
529 }
530 
531 enum {
532 	Opt_rd_pages, Opt_rd_nullio, Opt_err
533 };
534 
535 static match_table_t tokens = {
536 	{Opt_rd_pages, "rd_pages=%d"},
537 	{Opt_rd_nullio, "rd_nullio=%d"},
538 	{Opt_err, NULL}
539 };
540 
541 static ssize_t rd_set_configfs_dev_params(struct se_device *dev,
542 		const char *page, ssize_t count)
543 {
544 	struct rd_dev *rd_dev = RD_DEV(dev);
545 	char *orig, *ptr, *opts;
546 	substring_t args[MAX_OPT_ARGS];
547 	int ret = 0, arg, token;
548 
549 	opts = kstrdup(page, GFP_KERNEL);
550 	if (!opts)
551 		return -ENOMEM;
552 
553 	orig = opts;
554 
555 	while ((ptr = strsep(&opts, ",\n")) != NULL) {
556 		if (!*ptr)
557 			continue;
558 
559 		token = match_token(ptr, tokens, args);
560 		switch (token) {
561 		case Opt_rd_pages:
562 			match_int(args, &arg);
563 			rd_dev->rd_page_count = arg;
564 			pr_debug("RAMDISK: Referencing Page"
565 				" Count: %u\n", rd_dev->rd_page_count);
566 			rd_dev->rd_flags |= RDF_HAS_PAGE_COUNT;
567 			break;
568 		case Opt_rd_nullio:
569 			match_int(args, &arg);
570 			if (arg != 1)
571 				break;
572 
573 			pr_debug("RAMDISK: Setting NULLIO flag: %d\n", arg);
574 			rd_dev->rd_flags |= RDF_NULLIO;
575 			break;
576 		default:
577 			break;
578 		}
579 	}
580 
581 	kfree(orig);
582 	return (!ret) ? count : ret;
583 }
584 
585 static ssize_t rd_show_configfs_dev_params(struct se_device *dev, char *b)
586 {
587 	struct rd_dev *rd_dev = RD_DEV(dev);
588 
589 	ssize_t bl = sprintf(b, "TCM RamDisk ID: %u  RamDisk Makeup: rd_mcp\n",
590 			rd_dev->rd_dev_id);
591 	bl += sprintf(b + bl, "        PAGES/PAGE_SIZE: %u*%lu"
592 			"  SG_table_count: %u  nullio: %d\n", rd_dev->rd_page_count,
593 			PAGE_SIZE, rd_dev->sg_table_count,
594 			!!(rd_dev->rd_flags & RDF_NULLIO));
595 	return bl;
596 }
597 
598 static sector_t rd_get_blocks(struct se_device *dev)
599 {
600 	struct rd_dev *rd_dev = RD_DEV(dev);
601 
602 	unsigned long long blocks_long = ((rd_dev->rd_page_count * PAGE_SIZE) /
603 			dev->dev_attrib.block_size) - 1;
604 
605 	return blocks_long;
606 }
607 
608 static int rd_init_prot(struct se_device *dev)
609 {
610 	struct rd_dev *rd_dev = RD_DEV(dev);
611 
612         if (!dev->dev_attrib.pi_prot_type)
613 		return 0;
614 
615 	return rd_build_prot_space(rd_dev, dev->prot_length,
616 				   dev->dev_attrib.block_size);
617 }
618 
619 static void rd_free_prot(struct se_device *dev)
620 {
621 	struct rd_dev *rd_dev = RD_DEV(dev);
622 
623 	rd_release_prot_space(rd_dev);
624 }
625 
626 static struct sbc_ops rd_sbc_ops = {
627 	.execute_rw		= rd_execute_rw,
628 };
629 
630 static sense_reason_t
631 rd_parse_cdb(struct se_cmd *cmd)
632 {
633 	return sbc_parse_cdb(cmd, &rd_sbc_ops);
634 }
635 
636 DEF_TB_DEFAULT_ATTRIBS(rd_mcp);
637 
638 static struct configfs_attribute *rd_mcp_backend_dev_attrs[] = {
639 	&rd_mcp_dev_attrib_emulate_model_alias.attr,
640 	&rd_mcp_dev_attrib_emulate_dpo.attr,
641 	&rd_mcp_dev_attrib_emulate_fua_write.attr,
642 	&rd_mcp_dev_attrib_emulate_fua_read.attr,
643 	&rd_mcp_dev_attrib_emulate_write_cache.attr,
644 	&rd_mcp_dev_attrib_emulate_ua_intlck_ctrl.attr,
645 	&rd_mcp_dev_attrib_emulate_tas.attr,
646 	&rd_mcp_dev_attrib_emulate_tpu.attr,
647 	&rd_mcp_dev_attrib_emulate_tpws.attr,
648 	&rd_mcp_dev_attrib_emulate_caw.attr,
649 	&rd_mcp_dev_attrib_emulate_3pc.attr,
650 	&rd_mcp_dev_attrib_pi_prot_type.attr,
651 	&rd_mcp_dev_attrib_hw_pi_prot_type.attr,
652 	&rd_mcp_dev_attrib_pi_prot_format.attr,
653 	&rd_mcp_dev_attrib_enforce_pr_isids.attr,
654 	&rd_mcp_dev_attrib_is_nonrot.attr,
655 	&rd_mcp_dev_attrib_emulate_rest_reord.attr,
656 	&rd_mcp_dev_attrib_force_pr_aptpl.attr,
657 	&rd_mcp_dev_attrib_hw_block_size.attr,
658 	&rd_mcp_dev_attrib_block_size.attr,
659 	&rd_mcp_dev_attrib_hw_max_sectors.attr,
660 	&rd_mcp_dev_attrib_optimal_sectors.attr,
661 	&rd_mcp_dev_attrib_hw_queue_depth.attr,
662 	&rd_mcp_dev_attrib_queue_depth.attr,
663 	&rd_mcp_dev_attrib_max_unmap_lba_count.attr,
664 	&rd_mcp_dev_attrib_max_unmap_block_desc_count.attr,
665 	&rd_mcp_dev_attrib_unmap_granularity.attr,
666 	&rd_mcp_dev_attrib_unmap_granularity_alignment.attr,
667 	&rd_mcp_dev_attrib_max_write_same_len.attr,
668 	NULL,
669 };
670 
671 static struct se_subsystem_api rd_mcp_template = {
672 	.name			= "rd_mcp",
673 	.inquiry_prod		= "RAMDISK-MCP",
674 	.inquiry_rev		= RD_MCP_VERSION,
675 	.transport_type		= TRANSPORT_PLUGIN_VHBA_VDEV,
676 	.attach_hba		= rd_attach_hba,
677 	.detach_hba		= rd_detach_hba,
678 	.alloc_device		= rd_alloc_device,
679 	.configure_device	= rd_configure_device,
680 	.free_device		= rd_free_device,
681 	.parse_cdb		= rd_parse_cdb,
682 	.set_configfs_dev_params = rd_set_configfs_dev_params,
683 	.show_configfs_dev_params = rd_show_configfs_dev_params,
684 	.get_device_type	= sbc_get_device_type,
685 	.get_blocks		= rd_get_blocks,
686 	.init_prot		= rd_init_prot,
687 	.free_prot		= rd_free_prot,
688 };
689 
690 int __init rd_module_init(void)
691 {
692 	struct target_backend_cits *tbc = &rd_mcp_template.tb_cits;
693 	int ret;
694 
695 	target_core_setup_sub_cits(&rd_mcp_template);
696 	tbc->tb_dev_attrib_cit.ct_attrs = rd_mcp_backend_dev_attrs;
697 
698 	ret = transport_subsystem_register(&rd_mcp_template);
699 	if (ret < 0) {
700 		return ret;
701 	}
702 
703 	return 0;
704 }
705 
706 void rd_module_exit(void)
707 {
708 	transport_subsystem_release(&rd_mcp_template);
709 }
710