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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*******************************************************************************
3 * Filename: target_core_iblock.c
4 *
5 * This file contains the Storage Engine <-> Linux BlockIO transport
6 * specific functions.
7 *
8 * (c) Copyright 2003-2013 Datera, Inc.
9 *
10 * Nicholas A. Bellinger <nab@kernel.org>
11 *
12 ******************************************************************************/
13
14#include <linux/string.h>
15#include <linux/parser.h>
16#include <linux/timer.h>
17#include <linux/fs.h>
18#include <linux/blkdev.h>
19#include <linux/blk-integrity.h>
20#include <linux/slab.h>
21#include <linux/spinlock.h>
22#include <linux/bio.h>
23#include <linux/file.h>
24#include <linux/module.h>
25#include <linux/scatterlist.h>
26#include <linux/pr.h>
27#include <scsi/scsi_proto.h>
28#include <scsi/scsi_common.h>
29#include <linux/unaligned.h>
30
31#include <target/target_core_base.h>
32#include <target/target_core_backend.h>
33
34#include "target_core_iblock.h"
35#include "target_core_pr.h"
36
37#define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */
38#define IBLOCK_BIO_POOL_SIZE 128
39
40static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
41{
42 return container_of(dev, struct iblock_dev, dev);
43}
44
45
46static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
47{
48 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
49 " Generic Target Core Stack %s\n", hba->hba_id,
50 IBLOCK_VERSION, TARGET_CORE_VERSION);
51 return 0;
52}
53
54static void iblock_detach_hba(struct se_hba *hba)
55{
56}
57
58static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name)
59{
60 struct iblock_dev *ib_dev = NULL;
61
62 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
63 if (!ib_dev) {
64 pr_err("Unable to allocate struct iblock_dev\n");
65 return NULL;
66 }
67
68 ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug),
69 GFP_KERNEL);
70 if (!ib_dev->ibd_plug)
71 goto free_dev;
72
73 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
74
75 return &ib_dev->dev;
76
77free_dev:
78 kfree(ib_dev);
79 return NULL;
80}
81
82static bool iblock_configure_unmap(struct se_device *dev)
83{
84 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
85
86 return target_configure_unmap_from_queue(&dev->dev_attrib,
87 ib_dev->ibd_bd);
88}
89
90static int iblock_configure_device(struct se_device *dev)
91{
92 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
93 struct request_queue *q;
94 struct file *bdev_file;
95 struct block_device *bd;
96 struct blk_integrity *bi;
97 blk_mode_t mode = BLK_OPEN_READ;
98 unsigned int max_write_zeroes_sectors;
99 int ret;
100
101 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
102 pr_err("Missing udev_path= parameters for IBLOCK\n");
103 return -EINVAL;
104 }
105
106 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
107 if (ret) {
108 pr_err("IBLOCK: Unable to create bioset\n");
109 goto out;
110 }
111
112 pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
113 ib_dev->ibd_udev_path);
114
115 if (!ib_dev->ibd_readonly)
116 mode |= BLK_OPEN_WRITE;
117 else
118 dev->dev_flags |= DF_READ_ONLY;
119
120 bdev_file = bdev_file_open_by_path(ib_dev->ibd_udev_path, mode, ib_dev,
121 NULL);
122 if (IS_ERR(bdev_file)) {
123 ret = PTR_ERR(bdev_file);
124 goto out_free_bioset;
125 }
126 ib_dev->ibd_bdev_file = bdev_file;
127 ib_dev->ibd_bd = bd = file_bdev(bdev_file);
128
129 q = bdev_get_queue(bd);
130
131 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
132 dev->dev_attrib.hw_max_sectors = mult_frac(queue_max_hw_sectors(q),
133 SECTOR_SIZE,
134 dev->dev_attrib.hw_block_size);
135 dev->dev_attrib.hw_queue_depth = q->nr_requests;
136
137 /*
138 * Enable write same emulation for IBLOCK and use 0xFFFF as
139 * the smaller WRITE_SAME(10) only has a two-byte block count.
140 */
141 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd);
142 if (max_write_zeroes_sectors)
143 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors;
144 else
145 dev->dev_attrib.max_write_same_len = 0xFFFF;
146
147 if (bdev_nonrot(bd))
148 dev->dev_attrib.is_nonrot = 1;
149
150 bi = bdev_get_integrity(bd);
151 if (!bi)
152 return 0;
153
154 switch (bi->csum_type) {
155 case BLK_INTEGRITY_CSUM_IP:
156 pr_err("IBLOCK export of blk_integrity: %s not supported\n",
157 blk_integrity_profile_name(bi));
158 ret = -ENOSYS;
159 goto out_blkdev_put;
160 case BLK_INTEGRITY_CSUM_CRC:
161 if (bi->flags & BLK_INTEGRITY_REF_TAG)
162 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
163 else
164 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
165 break;
166 default:
167 break;
168 }
169
170 if (dev->dev_attrib.pi_prot_type) {
171 struct bio_set *bs = &ib_dev->ibd_bio_set;
172
173 if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) {
174 pr_err("Unable to allocate bioset for PI\n");
175 ret = -ENOMEM;
176 goto out_blkdev_put;
177 }
178 pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n",
179 &bs->bio_integrity_pool);
180 }
181
182 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
183 return 0;
184
185out_blkdev_put:
186 fput(ib_dev->ibd_bdev_file);
187out_free_bioset:
188 bioset_exit(&ib_dev->ibd_bio_set);
189out:
190 return ret;
191}
192
193static void iblock_dev_call_rcu(struct rcu_head *p)
194{
195 struct se_device *dev = container_of(p, struct se_device, rcu_head);
196 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
197
198 kfree(ib_dev->ibd_plug);
199 kfree(ib_dev);
200}
201
202static void iblock_free_device(struct se_device *dev)
203{
204 call_rcu(&dev->rcu_head, iblock_dev_call_rcu);
205}
206
207static void iblock_destroy_device(struct se_device *dev)
208{
209 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
210
211 if (ib_dev->ibd_bdev_file)
212 fput(ib_dev->ibd_bdev_file);
213 bioset_exit(&ib_dev->ibd_bio_set);
214}
215
216static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev)
217{
218 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev);
219 struct iblock_dev_plug *ib_dev_plug;
220
221 /*
222 * Each se_device has a per cpu work this can be run from. We
223 * shouldn't have multiple threads on the same cpu calling this
224 * at the same time.
225 */
226 ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()];
227 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags))
228 return NULL;
229
230 blk_start_plug(&ib_dev_plug->blk_plug);
231 return &ib_dev_plug->se_plug;
232}
233
234static void iblock_unplug_device(struct se_dev_plug *se_plug)
235{
236 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug,
237 struct iblock_dev_plug, se_plug);
238
239 blk_finish_plug(&ib_dev_plug->blk_plug);
240 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags);
241}
242
243static sector_t iblock_get_blocks(struct se_device *dev)
244{
245 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
246 u32 block_size = bdev_logical_block_size(ib_dev->ibd_bd);
247 unsigned long long blocks_long =
248 div_u64(bdev_nr_bytes(ib_dev->ibd_bd), block_size) - 1;
249
250 if (block_size == dev->dev_attrib.block_size)
251 return blocks_long;
252
253 switch (block_size) {
254 case 4096:
255 switch (dev->dev_attrib.block_size) {
256 case 2048:
257 blocks_long <<= 1;
258 break;
259 case 1024:
260 blocks_long <<= 2;
261 break;
262 case 512:
263 blocks_long <<= 3;
264 break;
265 default:
266 break;
267 }
268 break;
269 case 2048:
270 switch (dev->dev_attrib.block_size) {
271 case 4096:
272 blocks_long >>= 1;
273 break;
274 case 1024:
275 blocks_long <<= 1;
276 break;
277 case 512:
278 blocks_long <<= 2;
279 break;
280 default:
281 break;
282 }
283 break;
284 case 1024:
285 switch (dev->dev_attrib.block_size) {
286 case 4096:
287 blocks_long >>= 2;
288 break;
289 case 2048:
290 blocks_long >>= 1;
291 break;
292 case 512:
293 blocks_long <<= 1;
294 break;
295 default:
296 break;
297 }
298 break;
299 case 512:
300 switch (dev->dev_attrib.block_size) {
301 case 4096:
302 blocks_long >>= 3;
303 break;
304 case 2048:
305 blocks_long >>= 2;
306 break;
307 case 1024:
308 blocks_long >>= 1;
309 break;
310 default:
311 break;
312 }
313 break;
314 default:
315 break;
316 }
317
318 return blocks_long;
319}
320
321static void iblock_complete_cmd(struct se_cmd *cmd, blk_status_t blk_status)
322{
323 struct iblock_req *ibr = cmd->priv;
324 u8 status;
325
326 if (!refcount_dec_and_test(&ibr->pending))
327 return;
328
329 if (blk_status == BLK_STS_RESV_CONFLICT)
330 status = SAM_STAT_RESERVATION_CONFLICT;
331 else if (atomic_read(&ibr->ib_bio_err_cnt))
332 status = SAM_STAT_CHECK_CONDITION;
333 else
334 status = SAM_STAT_GOOD;
335
336 target_complete_cmd(cmd, status);
337 kfree(ibr);
338}
339
340static void iblock_bio_done(struct bio *bio)
341{
342 struct se_cmd *cmd = bio->bi_private;
343 struct iblock_req *ibr = cmd->priv;
344 blk_status_t blk_status = bio->bi_status;
345
346 if (bio->bi_status) {
347 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status);
348 /*
349 * Bump the ib_bio_err_cnt and release bio.
350 */
351 atomic_inc(&ibr->ib_bio_err_cnt);
352 smp_mb__after_atomic();
353 }
354
355 bio_put(bio);
356
357 iblock_complete_cmd(cmd, blk_status);
358}
359
360static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num,
361 blk_opf_t opf)
362{
363 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
364 struct bio *bio;
365
366 /*
367 * Only allocate as many vector entries as the bio code allows us to,
368 * we'll loop later on until we have handled the whole request.
369 */
370 bio = bio_alloc_bioset(ib_dev->ibd_bd, bio_max_segs(sg_num), opf,
371 GFP_NOIO, &ib_dev->ibd_bio_set);
372 if (!bio) {
373 pr_err("Unable to allocate memory for bio\n");
374 return NULL;
375 }
376
377 bio->bi_private = cmd;
378 bio->bi_end_io = &iblock_bio_done;
379 bio->bi_iter.bi_sector = lba;
380
381 return bio;
382}
383
384static void iblock_submit_bios(struct bio_list *list)
385{
386 struct blk_plug plug;
387 struct bio *bio;
388 /*
389 * The block layer handles nested plugs, so just plug/unplug to handle
390 * fabric drivers that didn't support batching and multi bio cmds.
391 */
392 blk_start_plug(&plug);
393 while ((bio = bio_list_pop(list)))
394 submit_bio(bio);
395 blk_finish_plug(&plug);
396}
397
398static void iblock_end_io_flush(struct bio *bio)
399{
400 struct se_cmd *cmd = bio->bi_private;
401
402 if (bio->bi_status)
403 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status);
404
405 if (cmd) {
406 if (bio->bi_status)
407 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
408 else
409 target_complete_cmd(cmd, SAM_STAT_GOOD);
410 }
411
412 bio_put(bio);
413}
414
415/*
416 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
417 * always flush the whole cache.
418 */
419static sense_reason_t
420iblock_execute_sync_cache(struct se_cmd *cmd)
421{
422 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
423 int immed = (cmd->t_task_cdb[1] & 0x2);
424 struct bio *bio;
425
426 /*
427 * If the Immediate bit is set, queue up the GOOD response
428 * for this SYNCHRONIZE_CACHE op.
429 */
430 if (immed)
431 target_complete_cmd(cmd, SAM_STAT_GOOD);
432
433 bio = bio_alloc(ib_dev->ibd_bd, 0, REQ_OP_WRITE | REQ_PREFLUSH,
434 GFP_KERNEL);
435 bio->bi_end_io = iblock_end_io_flush;
436 if (!immed)
437 bio->bi_private = cmd;
438 submit_bio(bio);
439 return 0;
440}
441
442static sense_reason_t
443iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
444{
445 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
446 struct se_device *dev = cmd->se_dev;
447 int ret;
448
449 ret = blkdev_issue_discard(bdev,
450 target_to_linux_sector(dev, lba),
451 target_to_linux_sector(dev, nolb),
452 GFP_KERNEL);
453 if (ret < 0) {
454 pr_err("blkdev_issue_discard() failed: %d\n", ret);
455 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
456 }
457
458 return 0;
459}
460
461static sense_reason_t
462iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd)
463{
464 struct se_device *dev = cmd->se_dev;
465 struct scatterlist *sg = &cmd->t_data_sg[0];
466 unsigned char *buf, *not_zero;
467 int ret;
468
469 buf = kmap(sg_page(sg)) + sg->offset;
470 if (!buf)
471 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
472 /*
473 * Fall back to block_execute_write_same() slow-path if
474 * incoming WRITE_SAME payload does not contain zeros.
475 */
476 not_zero = memchr_inv(buf, 0x00, cmd->data_length);
477 kunmap(sg_page(sg));
478
479 if (not_zero)
480 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
481
482 ret = blkdev_issue_zeroout(bdev,
483 target_to_linux_sector(dev, cmd->t_task_lba),
484 target_to_linux_sector(dev,
485 sbc_get_write_same_sectors(cmd)),
486 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
487 if (ret)
488 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
489
490 target_complete_cmd(cmd, SAM_STAT_GOOD);
491 return 0;
492}
493
494static sense_reason_t
495iblock_execute_write_same(struct se_cmd *cmd)
496{
497 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
498 struct iblock_req *ibr;
499 struct scatterlist *sg;
500 struct bio *bio;
501 struct bio_list list;
502 struct se_device *dev = cmd->se_dev;
503 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
504 sector_t sectors = target_to_linux_sector(dev,
505 sbc_get_write_same_sectors(cmd));
506
507 if (cmd->prot_op) {
508 pr_err("WRITE_SAME: Protection information with IBLOCK"
509 " backends not supported\n");
510 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
511 }
512
513 if (!cmd->t_data_nents)
514 return TCM_INVALID_CDB_FIELD;
515
516 sg = &cmd->t_data_sg[0];
517
518 if (cmd->t_data_nents > 1 ||
519 sg->length != cmd->se_dev->dev_attrib.block_size) {
520 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
521 " block_size: %u\n", cmd->t_data_nents, sg->length,
522 cmd->se_dev->dev_attrib.block_size);
523 return TCM_INVALID_CDB_FIELD;
524 }
525
526 if (bdev_write_zeroes_sectors(bdev)) {
527 if (!iblock_execute_zero_out(bdev, cmd))
528 return 0;
529 }
530
531 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
532 if (!ibr)
533 goto fail;
534 cmd->priv = ibr;
535
536 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
537 if (!bio)
538 goto fail_free_ibr;
539
540 bio_list_init(&list);
541 bio_list_add(&list, bio);
542
543 refcount_set(&ibr->pending, 1);
544
545 while (sectors) {
546 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
547 != sg->length) {
548
549 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
550 if (!bio)
551 goto fail_put_bios;
552
553 refcount_inc(&ibr->pending);
554 bio_list_add(&list, bio);
555 }
556
557 /* Always in 512 byte units for Linux/Block */
558 block_lba += sg->length >> SECTOR_SHIFT;
559 sectors -= sg->length >> SECTOR_SHIFT;
560 }
561
562 iblock_submit_bios(&list);
563 return 0;
564
565fail_put_bios:
566 while ((bio = bio_list_pop(&list)))
567 bio_put(bio);
568fail_free_ibr:
569 kfree(ibr);
570fail:
571 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
572}
573
574enum {
575 Opt_udev_path, Opt_readonly, Opt_force, Opt_err
576};
577
578static match_table_t tokens = {
579 {Opt_udev_path, "udev_path=%s"},
580 {Opt_readonly, "readonly=%d"},
581 {Opt_force, "force=%d"},
582 {Opt_err, NULL}
583};
584
585static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
586 const char *page, ssize_t count)
587{
588 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
589 char *orig, *ptr, *arg_p, *opts;
590 substring_t args[MAX_OPT_ARGS];
591 int ret = 0, token;
592 unsigned long tmp_readonly;
593
594 opts = kstrdup(page, GFP_KERNEL);
595 if (!opts)
596 return -ENOMEM;
597
598 orig = opts;
599
600 while ((ptr = strsep(&opts, ",\n")) != NULL) {
601 if (!*ptr)
602 continue;
603
604 token = match_token(ptr, tokens, args);
605 switch (token) {
606 case Opt_udev_path:
607 if (ib_dev->ibd_bd) {
608 pr_err("Unable to set udev_path= while"
609 " ib_dev->ibd_bd exists\n");
610 ret = -EEXIST;
611 goto out;
612 }
613 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
614 SE_UDEV_PATH_LEN) == 0) {
615 ret = -EINVAL;
616 break;
617 }
618 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
619 ib_dev->ibd_udev_path);
620 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
621 break;
622 case Opt_readonly:
623 arg_p = match_strdup(&args[0]);
624 if (!arg_p) {
625 ret = -ENOMEM;
626 break;
627 }
628 ret = kstrtoul(arg_p, 0, &tmp_readonly);
629 kfree(arg_p);
630 if (ret < 0) {
631 pr_err("kstrtoul() failed for"
632 " readonly=\n");
633 goto out;
634 }
635 ib_dev->ibd_readonly = tmp_readonly;
636 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
637 break;
638 case Opt_force:
639 break;
640 default:
641 break;
642 }
643 }
644
645out:
646 kfree(orig);
647 return (!ret) ? count : ret;
648}
649
650static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
651{
652 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
653 struct block_device *bd = ib_dev->ibd_bd;
654 ssize_t bl = 0;
655
656 if (bd)
657 bl += sprintf(b + bl, "iBlock device: %pg", bd);
658 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
659 bl += sprintf(b + bl, " UDEV PATH: %s",
660 ib_dev->ibd_udev_path);
661 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly);
662
663 bl += sprintf(b + bl, " ");
664 if (bd) {
665 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
666 MAJOR(bd->bd_dev), MINOR(bd->bd_dev),
667 "CLAIMED: IBLOCK");
668 } else {
669 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
670 }
671
672 return bl;
673}
674
675static int
676iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio,
677 struct sg_mapping_iter *miter)
678{
679 struct se_device *dev = cmd->se_dev;
680 struct blk_integrity *bi;
681 struct bio_integrity_payload *bip;
682 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
683 int rc;
684 size_t resid, len;
685
686 bi = bdev_get_integrity(ib_dev->ibd_bd);
687 if (!bi) {
688 pr_err("Unable to locate bio_integrity\n");
689 return -ENODEV;
690 }
691
692 bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents));
693 if (IS_ERR(bip)) {
694 pr_err("Unable to allocate bio_integrity_payload\n");
695 return PTR_ERR(bip);
696 }
697
698 /* virtual start sector must be in integrity interval units */
699 bip_set_seed(bip, bio->bi_iter.bi_sector >>
700 (bi->interval_exp - SECTOR_SHIFT));
701
702 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size,
703 (unsigned long long)bip->bip_iter.bi_sector);
704
705 resid = bio_integrity_bytes(bi, bio_sectors(bio));
706 while (resid > 0 && sg_miter_next(miter)) {
707
708 len = min_t(size_t, miter->length, resid);
709 rc = bio_integrity_add_page(bio, miter->page, len,
710 offset_in_page(miter->addr));
711 if (rc != len) {
712 pr_err("bio_integrity_add_page() failed; %d\n", rc);
713 sg_miter_stop(miter);
714 return -ENOMEM;
715 }
716
717 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n",
718 miter->page, len, offset_in_page(miter->addr));
719
720 resid -= len;
721 if (len < miter->length)
722 miter->consumed -= miter->length - len;
723 }
724 sg_miter_stop(miter);
725
726 return 0;
727}
728
729static sense_reason_t
730iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
731 enum dma_data_direction data_direction)
732{
733 struct se_device *dev = cmd->se_dev;
734 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
735 struct iblock_req *ibr;
736 struct bio *bio;
737 struct bio_list list;
738 struct scatterlist *sg;
739 u32 sg_num = sgl_nents;
740 blk_opf_t opf;
741 unsigned bio_cnt;
742 int i, rc;
743 struct sg_mapping_iter prot_miter;
744 unsigned int miter_dir;
745
746 if (data_direction == DMA_TO_DEVICE) {
747 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
748
749 /*
750 * Set bits to indicate WRITE_ODIRECT so we are not throttled
751 * by WBT.
752 */
753 opf = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
754 /*
755 * Force writethrough using REQ_FUA if a volatile write cache
756 * is not enabled, or if initiator set the Force Unit Access bit.
757 */
758 miter_dir = SG_MITER_TO_SG;
759 if (bdev_fua(ib_dev->ibd_bd)) {
760 if (cmd->se_cmd_flags & SCF_FUA)
761 opf |= REQ_FUA;
762 else if (!bdev_write_cache(ib_dev->ibd_bd))
763 opf |= REQ_FUA;
764 }
765 } else {
766 opf = REQ_OP_READ;
767 miter_dir = SG_MITER_FROM_SG;
768 }
769
770 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
771 if (!ibr)
772 goto fail;
773 cmd->priv = ibr;
774
775 if (!sgl_nents) {
776 refcount_set(&ibr->pending, 1);
777 iblock_complete_cmd(cmd, BLK_STS_OK);
778 return 0;
779 }
780
781 bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf);
782 if (!bio)
783 goto fail_free_ibr;
784
785 bio_list_init(&list);
786 bio_list_add(&list, bio);
787
788 refcount_set(&ibr->pending, 2);
789 bio_cnt = 1;
790
791 if (cmd->prot_type && dev->dev_attrib.pi_prot_type)
792 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents,
793 miter_dir);
794
795 for_each_sg(sgl, sg, sgl_nents, i) {
796 /*
797 * XXX: if the length the device accepts is shorter than the
798 * length of the S/G list entry this will cause and
799 * endless loop. Better hope no driver uses huge pages.
800 */
801 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
802 != sg->length) {
803 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
804 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
805 if (rc)
806 goto fail_put_bios;
807 }
808
809 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
810 iblock_submit_bios(&list);
811 bio_cnt = 0;
812 }
813
814 bio = iblock_get_bio(cmd, block_lba, sg_num, opf);
815 if (!bio)
816 goto fail_put_bios;
817
818 refcount_inc(&ibr->pending);
819 bio_list_add(&list, bio);
820 bio_cnt++;
821 }
822
823 /* Always in 512 byte units for Linux/Block */
824 block_lba += sg->length >> SECTOR_SHIFT;
825 sg_num--;
826 }
827
828 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
829 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
830 if (rc)
831 goto fail_put_bios;
832 }
833
834 iblock_submit_bios(&list);
835 iblock_complete_cmd(cmd, BLK_STS_OK);
836 return 0;
837
838fail_put_bios:
839 while ((bio = bio_list_pop(&list)))
840 bio_put(bio);
841fail_free_ibr:
842 kfree(ibr);
843fail:
844 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
845}
846
847static sense_reason_t iblock_execute_pr_out(struct se_cmd *cmd, u8 sa, u64 key,
848 u64 sa_key, u8 type, bool aptpl)
849{
850 struct se_device *dev = cmd->se_dev;
851 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
852 struct block_device *bdev = ib_dev->ibd_bd;
853 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
854 int ret;
855
856 if (!ops) {
857 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
858 return TCM_UNSUPPORTED_SCSI_OPCODE;
859 }
860
861 switch (sa) {
862 case PRO_REGISTER:
863 case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
864 if (!ops->pr_register) {
865 pr_err("block device does not support pr_register.\n");
866 return TCM_UNSUPPORTED_SCSI_OPCODE;
867 }
868
869 /* The block layer pr ops always enables aptpl */
870 if (!aptpl)
871 pr_info("APTPL not set by initiator, but will be used.\n");
872
873 ret = ops->pr_register(bdev, key, sa_key,
874 sa == PRO_REGISTER ? 0 : PR_FL_IGNORE_KEY);
875 break;
876 case PRO_RESERVE:
877 if (!ops->pr_reserve) {
878 pr_err("block_device does not support pr_reserve.\n");
879 return TCM_UNSUPPORTED_SCSI_OPCODE;
880 }
881
882 ret = ops->pr_reserve(bdev, key, scsi_pr_type_to_block(type), 0);
883 break;
884 case PRO_CLEAR:
885 if (!ops->pr_clear) {
886 pr_err("block_device does not support pr_clear.\n");
887 return TCM_UNSUPPORTED_SCSI_OPCODE;
888 }
889
890 ret = ops->pr_clear(bdev, key);
891 break;
892 case PRO_PREEMPT:
893 case PRO_PREEMPT_AND_ABORT:
894 if (!ops->pr_clear) {
895 pr_err("block_device does not support pr_preempt.\n");
896 return TCM_UNSUPPORTED_SCSI_OPCODE;
897 }
898
899 ret = ops->pr_preempt(bdev, key, sa_key,
900 scsi_pr_type_to_block(type),
901 sa == PRO_PREEMPT_AND_ABORT);
902 break;
903 case PRO_RELEASE:
904 if (!ops->pr_clear) {
905 pr_err("block_device does not support pr_pclear.\n");
906 return TCM_UNSUPPORTED_SCSI_OPCODE;
907 }
908
909 ret = ops->pr_release(bdev, key, scsi_pr_type_to_block(type));
910 break;
911 default:
912 pr_err("Unknown PERSISTENT_RESERVE_OUT SA: 0x%02x\n", sa);
913 return TCM_UNSUPPORTED_SCSI_OPCODE;
914 }
915
916 if (!ret)
917 return TCM_NO_SENSE;
918 else if (ret == PR_STS_RESERVATION_CONFLICT)
919 return TCM_RESERVATION_CONFLICT;
920 else
921 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
922}
923
924static void iblock_pr_report_caps(unsigned char *param_data)
925{
926 u16 len = 8;
927
928 put_unaligned_be16(len, ¶m_data[0]);
929 /*
930 * When using the pr_ops passthrough method we only support exporting
931 * the device through one target port because from the backend module
932 * level we can't see the target port config. As a result we only
933 * support registration directly from the I_T nexus the cmd is sent
934 * through and do not set ATP_C here.
935 *
936 * The block layer pr_ops do not support passing in initiators so
937 * we don't set SIP_C here.
938 */
939 /* PTPL_C: Persistence across Target Power Loss bit */
940 param_data[2] |= 0x01;
941 /*
942 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
943 * set the TMV: Task Mask Valid bit.
944 */
945 param_data[3] |= 0x80;
946 /*
947 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
948 */
949 param_data[3] |= 0x10; /* ALLOW COMMANDs field 001b */
950 /*
951 * PTPL_A: Persistence across Target Power Loss Active bit. The block
952 * layer pr ops always enables this so report it active.
953 */
954 param_data[3] |= 0x01;
955 /*
956 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 212 spc4r37.
957 */
958 param_data[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
959 param_data[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
960 param_data[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
961 param_data[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
962 param_data[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
963 param_data[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
964}
965
966static sense_reason_t iblock_pr_read_keys(struct se_cmd *cmd,
967 unsigned char *param_data)
968{
969 struct se_device *dev = cmd->se_dev;
970 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
971 struct block_device *bdev = ib_dev->ibd_bd;
972 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
973 int i, len, paths, data_offset;
974 struct pr_keys *keys;
975 sense_reason_t ret;
976
977 if (!ops) {
978 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
979 return TCM_UNSUPPORTED_SCSI_OPCODE;
980 }
981
982 if (!ops->pr_read_keys) {
983 pr_err("Block device does not support read_keys.\n");
984 return TCM_UNSUPPORTED_SCSI_OPCODE;
985 }
986
987 /*
988 * We don't know what's under us, but dm-multipath will register every
989 * path with the same key, so start off with enough space for 16 paths.
990 * which is not a lot of memory and should normally be enough.
991 */
992 paths = 16;
993retry:
994 len = 8 * paths;
995 keys = kzalloc(sizeof(*keys) + len, GFP_KERNEL);
996 if (!keys)
997 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
998
999 keys->num_keys = paths;
1000 if (!ops->pr_read_keys(bdev, keys)) {
1001 if (keys->num_keys > paths) {
1002 kfree(keys);
1003 paths *= 2;
1004 goto retry;
1005 }
1006 } else {
1007 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1008 goto free_keys;
1009 }
1010
1011 ret = TCM_NO_SENSE;
1012
1013 put_unaligned_be32(keys->generation, ¶m_data[0]);
1014 if (!keys->num_keys) {
1015 put_unaligned_be32(0, ¶m_data[4]);
1016 goto free_keys;
1017 }
1018
1019 put_unaligned_be32(8 * keys->num_keys, ¶m_data[4]);
1020
1021 data_offset = 8;
1022 for (i = 0; i < keys->num_keys; i++) {
1023 if (data_offset + 8 > cmd->data_length)
1024 break;
1025
1026 put_unaligned_be64(keys->keys[i], ¶m_data[data_offset]);
1027 data_offset += 8;
1028 }
1029
1030free_keys:
1031 kfree(keys);
1032 return ret;
1033}
1034
1035static sense_reason_t iblock_pr_read_reservation(struct se_cmd *cmd,
1036 unsigned char *param_data)
1037{
1038 struct se_device *dev = cmd->se_dev;
1039 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1040 struct block_device *bdev = ib_dev->ibd_bd;
1041 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
1042 struct pr_held_reservation rsv = { };
1043
1044 if (!ops) {
1045 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
1046 return TCM_UNSUPPORTED_SCSI_OPCODE;
1047 }
1048
1049 if (!ops->pr_read_reservation) {
1050 pr_err("Block device does not support read_keys.\n");
1051 return TCM_UNSUPPORTED_SCSI_OPCODE;
1052 }
1053
1054 if (ops->pr_read_reservation(bdev, &rsv))
1055 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1056
1057 put_unaligned_be32(rsv.generation, ¶m_data[0]);
1058 if (!block_pr_type_to_scsi(rsv.type)) {
1059 put_unaligned_be32(0, ¶m_data[4]);
1060 return TCM_NO_SENSE;
1061 }
1062
1063 put_unaligned_be32(16, ¶m_data[4]);
1064
1065 if (cmd->data_length < 16)
1066 return TCM_NO_SENSE;
1067 put_unaligned_be64(rsv.key, ¶m_data[8]);
1068
1069 if (cmd->data_length < 22)
1070 return TCM_NO_SENSE;
1071 param_data[21] = block_pr_type_to_scsi(rsv.type);
1072
1073 return TCM_NO_SENSE;
1074}
1075
1076static sense_reason_t iblock_execute_pr_in(struct se_cmd *cmd, u8 sa,
1077 unsigned char *param_data)
1078{
1079 sense_reason_t ret = TCM_NO_SENSE;
1080
1081 switch (sa) {
1082 case PRI_REPORT_CAPABILITIES:
1083 iblock_pr_report_caps(param_data);
1084 break;
1085 case PRI_READ_KEYS:
1086 ret = iblock_pr_read_keys(cmd, param_data);
1087 break;
1088 case PRI_READ_RESERVATION:
1089 ret = iblock_pr_read_reservation(cmd, param_data);
1090 break;
1091 default:
1092 pr_err("Unknown PERSISTENT_RESERVE_IN SA: 0x%02x\n", sa);
1093 return TCM_UNSUPPORTED_SCSI_OPCODE;
1094 }
1095
1096 return ret;
1097}
1098
1099static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev)
1100{
1101 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1102 struct block_device *bd = ib_dev->ibd_bd;
1103 int ret;
1104
1105 ret = bdev_alignment_offset(bd);
1106 if (ret == -1)
1107 return 0;
1108
1109 /* convert offset-bytes to offset-lbas */
1110 return ret / bdev_logical_block_size(bd);
1111}
1112
1113static unsigned int iblock_get_lbppbe(struct se_device *dev)
1114{
1115 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1116 struct block_device *bd = ib_dev->ibd_bd;
1117 unsigned int logs_per_phys =
1118 bdev_physical_block_size(bd) / bdev_logical_block_size(bd);
1119
1120 return ilog2(logs_per_phys);
1121}
1122
1123static unsigned int iblock_get_io_min(struct se_device *dev)
1124{
1125 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1126 struct block_device *bd = ib_dev->ibd_bd;
1127
1128 return bdev_io_min(bd);
1129}
1130
1131static unsigned int iblock_get_io_opt(struct se_device *dev)
1132{
1133 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1134 struct block_device *bd = ib_dev->ibd_bd;
1135
1136 return bdev_io_opt(bd);
1137}
1138
1139static struct exec_cmd_ops iblock_exec_cmd_ops = {
1140 .execute_rw = iblock_execute_rw,
1141 .execute_sync_cache = iblock_execute_sync_cache,
1142 .execute_write_same = iblock_execute_write_same,
1143 .execute_unmap = iblock_execute_unmap,
1144 .execute_pr_out = iblock_execute_pr_out,
1145 .execute_pr_in = iblock_execute_pr_in,
1146};
1147
1148static sense_reason_t
1149iblock_parse_cdb(struct se_cmd *cmd)
1150{
1151 return sbc_parse_cdb(cmd, &iblock_exec_cmd_ops);
1152}
1153
1154static bool iblock_get_write_cache(struct se_device *dev)
1155{
1156 return bdev_write_cache(IBLOCK_DEV(dev)->ibd_bd);
1157}
1158
1159static const struct target_backend_ops iblock_ops = {
1160 .name = "iblock",
1161 .inquiry_prod = "IBLOCK",
1162 .transport_flags_changeable = TRANSPORT_FLAG_PASSTHROUGH_PGR,
1163 .inquiry_rev = IBLOCK_VERSION,
1164 .owner = THIS_MODULE,
1165 .attach_hba = iblock_attach_hba,
1166 .detach_hba = iblock_detach_hba,
1167 .alloc_device = iblock_alloc_device,
1168 .configure_device = iblock_configure_device,
1169 .destroy_device = iblock_destroy_device,
1170 .free_device = iblock_free_device,
1171 .configure_unmap = iblock_configure_unmap,
1172 .plug_device = iblock_plug_device,
1173 .unplug_device = iblock_unplug_device,
1174 .parse_cdb = iblock_parse_cdb,
1175 .set_configfs_dev_params = iblock_set_configfs_dev_params,
1176 .show_configfs_dev_params = iblock_show_configfs_dev_params,
1177 .get_device_type = sbc_get_device_type,
1178 .get_blocks = iblock_get_blocks,
1179 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas,
1180 .get_lbppbe = iblock_get_lbppbe,
1181 .get_io_min = iblock_get_io_min,
1182 .get_io_opt = iblock_get_io_opt,
1183 .get_write_cache = iblock_get_write_cache,
1184 .tb_dev_attrib_attrs = sbc_attrib_attrs,
1185};
1186
1187static int __init iblock_module_init(void)
1188{
1189 return transport_backend_register(&iblock_ops);
1190}
1191
1192static void __exit iblock_module_exit(void)
1193{
1194 target_backend_unregister(&iblock_ops);
1195}
1196
1197MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
1198MODULE_AUTHOR("nab@Linux-iSCSI.org");
1199MODULE_LICENSE("GPL");
1200
1201module_init(iblock_module_init);
1202module_exit(iblock_module_exit);
1/*******************************************************************************
2 * Filename: target_core_iblock.c
3 *
4 * This file contains the Storage Engine <-> Linux BlockIO 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/fs.h>
31#include <linux/blkdev.h>
32#include <linux/slab.h>
33#include <linux/spinlock.h>
34#include <linux/bio.h>
35#include <linux/genhd.h>
36#include <linux/file.h>
37#include <linux/module.h>
38#include <scsi/scsi.h>
39#include <scsi/scsi_host.h>
40#include <asm/unaligned.h>
41
42#include <target/target_core_base.h>
43#include <target/target_core_backend.h>
44
45#include "target_core_iblock.h"
46
47#define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */
48#define IBLOCK_BIO_POOL_SIZE 128
49
50static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
51{
52 return container_of(dev, struct iblock_dev, dev);
53}
54
55
56static struct se_subsystem_api iblock_template;
57
58/* iblock_attach_hba(): (Part of se_subsystem_api_t template)
59 *
60 *
61 */
62static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
63{
64 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
65 " Generic Target Core Stack %s\n", hba->hba_id,
66 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
67 return 0;
68}
69
70static void iblock_detach_hba(struct se_hba *hba)
71{
72}
73
74static struct se_device *iblock_alloc_device(struct se_hba *hba, const char *name)
75{
76 struct iblock_dev *ib_dev = NULL;
77
78 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
79 if (!ib_dev) {
80 pr_err("Unable to allocate struct iblock_dev\n");
81 return NULL;
82 }
83
84 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
85
86 return &ib_dev->dev;
87}
88
89static int iblock_configure_device(struct se_device *dev)
90{
91 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
92 struct request_queue *q;
93 struct block_device *bd = NULL;
94 struct blk_integrity *bi;
95 fmode_t mode;
96 int ret = -ENOMEM;
97
98 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
99 pr_err("Missing udev_path= parameters for IBLOCK\n");
100 return -EINVAL;
101 }
102
103 ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0);
104 if (!ib_dev->ibd_bio_set) {
105 pr_err("IBLOCK: Unable to create bioset\n");
106 goto out;
107 }
108
109 pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
110 ib_dev->ibd_udev_path);
111
112 mode = FMODE_READ|FMODE_EXCL;
113 if (!ib_dev->ibd_readonly)
114 mode |= FMODE_WRITE;
115
116 bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev);
117 if (IS_ERR(bd)) {
118 ret = PTR_ERR(bd);
119 goto out_free_bioset;
120 }
121 ib_dev->ibd_bd = bd;
122
123 q = bdev_get_queue(bd);
124
125 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
126 dev->dev_attrib.hw_max_sectors = UINT_MAX;
127 dev->dev_attrib.hw_queue_depth = q->nr_requests;
128
129 /*
130 * Check if the underlying struct block_device request_queue supports
131 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
132 * in ATA and we need to set TPE=1
133 */
134 if (blk_queue_discard(q)) {
135 dev->dev_attrib.max_unmap_lba_count =
136 q->limits.max_discard_sectors;
137
138 /*
139 * Currently hardcoded to 1 in Linux/SCSI code..
140 */
141 dev->dev_attrib.max_unmap_block_desc_count = 1;
142 dev->dev_attrib.unmap_granularity =
143 q->limits.discard_granularity >> 9;
144 dev->dev_attrib.unmap_granularity_alignment =
145 q->limits.discard_alignment;
146
147 pr_debug("IBLOCK: BLOCK Discard support available,"
148 " disabled by default\n");
149 }
150 /*
151 * Enable write same emulation for IBLOCK and use 0xFFFF as
152 * the smaller WRITE_SAME(10) only has a two-byte block count.
153 */
154 dev->dev_attrib.max_write_same_len = 0xFFFF;
155
156 if (blk_queue_nonrot(q))
157 dev->dev_attrib.is_nonrot = 1;
158
159 bi = bdev_get_integrity(bd);
160 if (bi) {
161 struct bio_set *bs = ib_dev->ibd_bio_set;
162
163 if (!strcmp(bi->name, "T10-DIF-TYPE3-IP") ||
164 !strcmp(bi->name, "T10-DIF-TYPE1-IP")) {
165 pr_err("IBLOCK export of blk_integrity: %s not"
166 " supported\n", bi->name);
167 ret = -ENOSYS;
168 goto out_blkdev_put;
169 }
170
171 if (!strcmp(bi->name, "T10-DIF-TYPE3-CRC")) {
172 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
173 } else if (!strcmp(bi->name, "T10-DIF-TYPE1-CRC")) {
174 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
175 }
176
177 if (dev->dev_attrib.pi_prot_type) {
178 if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) {
179 pr_err("Unable to allocate bioset for PI\n");
180 ret = -ENOMEM;
181 goto out_blkdev_put;
182 }
183 pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n",
184 bs->bio_integrity_pool);
185 }
186 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
187 }
188
189 return 0;
190
191out_blkdev_put:
192 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
193out_free_bioset:
194 bioset_free(ib_dev->ibd_bio_set);
195 ib_dev->ibd_bio_set = NULL;
196out:
197 return ret;
198}
199
200static void iblock_free_device(struct se_device *dev)
201{
202 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
203
204 if (ib_dev->ibd_bd != NULL)
205 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
206 if (ib_dev->ibd_bio_set != NULL)
207 bioset_free(ib_dev->ibd_bio_set);
208
209 kfree(ib_dev);
210}
211
212static unsigned long long iblock_emulate_read_cap_with_block_size(
213 struct se_device *dev,
214 struct block_device *bd,
215 struct request_queue *q)
216{
217 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
218 bdev_logical_block_size(bd)) - 1);
219 u32 block_size = bdev_logical_block_size(bd);
220
221 if (block_size == dev->dev_attrib.block_size)
222 return blocks_long;
223
224 switch (block_size) {
225 case 4096:
226 switch (dev->dev_attrib.block_size) {
227 case 2048:
228 blocks_long <<= 1;
229 break;
230 case 1024:
231 blocks_long <<= 2;
232 break;
233 case 512:
234 blocks_long <<= 3;
235 default:
236 break;
237 }
238 break;
239 case 2048:
240 switch (dev->dev_attrib.block_size) {
241 case 4096:
242 blocks_long >>= 1;
243 break;
244 case 1024:
245 blocks_long <<= 1;
246 break;
247 case 512:
248 blocks_long <<= 2;
249 break;
250 default:
251 break;
252 }
253 break;
254 case 1024:
255 switch (dev->dev_attrib.block_size) {
256 case 4096:
257 blocks_long >>= 2;
258 break;
259 case 2048:
260 blocks_long >>= 1;
261 break;
262 case 512:
263 blocks_long <<= 1;
264 break;
265 default:
266 break;
267 }
268 break;
269 case 512:
270 switch (dev->dev_attrib.block_size) {
271 case 4096:
272 blocks_long >>= 3;
273 break;
274 case 2048:
275 blocks_long >>= 2;
276 break;
277 case 1024:
278 blocks_long >>= 1;
279 break;
280 default:
281 break;
282 }
283 break;
284 default:
285 break;
286 }
287
288 return blocks_long;
289}
290
291static void iblock_complete_cmd(struct se_cmd *cmd)
292{
293 struct iblock_req *ibr = cmd->priv;
294 u8 status;
295
296 if (!atomic_dec_and_test(&ibr->pending))
297 return;
298
299 if (atomic_read(&ibr->ib_bio_err_cnt))
300 status = SAM_STAT_CHECK_CONDITION;
301 else
302 status = SAM_STAT_GOOD;
303
304 target_complete_cmd(cmd, status);
305 kfree(ibr);
306}
307
308static void iblock_bio_done(struct bio *bio, int err)
309{
310 struct se_cmd *cmd = bio->bi_private;
311 struct iblock_req *ibr = cmd->priv;
312
313 /*
314 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
315 */
316 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
317 err = -EIO;
318
319 if (err != 0) {
320 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
321 " err: %d\n", bio, err);
322 /*
323 * Bump the ib_bio_err_cnt and release bio.
324 */
325 atomic_inc(&ibr->ib_bio_err_cnt);
326 smp_mb__after_atomic_inc();
327 }
328
329 bio_put(bio);
330
331 iblock_complete_cmd(cmd);
332}
333
334static struct bio *
335iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num)
336{
337 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
338 struct bio *bio;
339
340 /*
341 * Only allocate as many vector entries as the bio code allows us to,
342 * we'll loop later on until we have handled the whole request.
343 */
344 if (sg_num > BIO_MAX_PAGES)
345 sg_num = BIO_MAX_PAGES;
346
347 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
348 if (!bio) {
349 pr_err("Unable to allocate memory for bio\n");
350 return NULL;
351 }
352
353 bio->bi_bdev = ib_dev->ibd_bd;
354 bio->bi_private = cmd;
355 bio->bi_end_io = &iblock_bio_done;
356 bio->bi_iter.bi_sector = lba;
357
358 return bio;
359}
360
361static void iblock_submit_bios(struct bio_list *list, int rw)
362{
363 struct blk_plug plug;
364 struct bio *bio;
365
366 blk_start_plug(&plug);
367 while ((bio = bio_list_pop(list)))
368 submit_bio(rw, bio);
369 blk_finish_plug(&plug);
370}
371
372static void iblock_end_io_flush(struct bio *bio, int err)
373{
374 struct se_cmd *cmd = bio->bi_private;
375
376 if (err)
377 pr_err("IBLOCK: cache flush failed: %d\n", err);
378
379 if (cmd) {
380 if (err)
381 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
382 else
383 target_complete_cmd(cmd, SAM_STAT_GOOD);
384 }
385
386 bio_put(bio);
387}
388
389/*
390 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
391 * always flush the whole cache.
392 */
393static sense_reason_t
394iblock_execute_sync_cache(struct se_cmd *cmd)
395{
396 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
397 int immed = (cmd->t_task_cdb[1] & 0x2);
398 struct bio *bio;
399
400 /*
401 * If the Immediate bit is set, queue up the GOOD response
402 * for this SYNCHRONIZE_CACHE op.
403 */
404 if (immed)
405 target_complete_cmd(cmd, SAM_STAT_GOOD);
406
407 bio = bio_alloc(GFP_KERNEL, 0);
408 bio->bi_end_io = iblock_end_io_flush;
409 bio->bi_bdev = ib_dev->ibd_bd;
410 if (!immed)
411 bio->bi_private = cmd;
412 submit_bio(WRITE_FLUSH, bio);
413 return 0;
414}
415
416static sense_reason_t
417iblock_do_unmap(struct se_cmd *cmd, void *priv,
418 sector_t lba, sector_t nolb)
419{
420 struct block_device *bdev = priv;
421 int ret;
422
423 ret = blkdev_issue_discard(bdev, lba, nolb, GFP_KERNEL, 0);
424 if (ret < 0) {
425 pr_err("blkdev_issue_discard() failed: %d\n", ret);
426 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
427 }
428
429 return 0;
430}
431
432static sense_reason_t
433iblock_execute_unmap(struct se_cmd *cmd)
434{
435 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
436
437 return sbc_execute_unmap(cmd, iblock_do_unmap, bdev);
438}
439
440static sense_reason_t
441iblock_execute_write_same_unmap(struct se_cmd *cmd)
442{
443 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
444 sector_t lba = cmd->t_task_lba;
445 sector_t nolb = sbc_get_write_same_sectors(cmd);
446 int ret;
447
448 ret = iblock_do_unmap(cmd, bdev, lba, nolb);
449 if (ret)
450 return ret;
451
452 target_complete_cmd(cmd, GOOD);
453 return 0;
454}
455
456static sense_reason_t
457iblock_execute_write_same(struct se_cmd *cmd)
458{
459 struct iblock_req *ibr;
460 struct scatterlist *sg;
461 struct bio *bio;
462 struct bio_list list;
463 sector_t block_lba = cmd->t_task_lba;
464 sector_t sectors = sbc_get_write_same_sectors(cmd);
465
466 sg = &cmd->t_data_sg[0];
467
468 if (cmd->t_data_nents > 1 ||
469 sg->length != cmd->se_dev->dev_attrib.block_size) {
470 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
471 " block_size: %u\n", cmd->t_data_nents, sg->length,
472 cmd->se_dev->dev_attrib.block_size);
473 return TCM_INVALID_CDB_FIELD;
474 }
475
476 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
477 if (!ibr)
478 goto fail;
479 cmd->priv = ibr;
480
481 bio = iblock_get_bio(cmd, block_lba, 1);
482 if (!bio)
483 goto fail_free_ibr;
484
485 bio_list_init(&list);
486 bio_list_add(&list, bio);
487
488 atomic_set(&ibr->pending, 1);
489
490 while (sectors) {
491 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
492 != sg->length) {
493
494 bio = iblock_get_bio(cmd, block_lba, 1);
495 if (!bio)
496 goto fail_put_bios;
497
498 atomic_inc(&ibr->pending);
499 bio_list_add(&list, bio);
500 }
501
502 /* Always in 512 byte units for Linux/Block */
503 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
504 sectors -= 1;
505 }
506
507 iblock_submit_bios(&list, WRITE);
508 return 0;
509
510fail_put_bios:
511 while ((bio = bio_list_pop(&list)))
512 bio_put(bio);
513fail_free_ibr:
514 kfree(ibr);
515fail:
516 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
517}
518
519enum {
520 Opt_udev_path, Opt_readonly, Opt_force, Opt_err
521};
522
523static match_table_t tokens = {
524 {Opt_udev_path, "udev_path=%s"},
525 {Opt_readonly, "readonly=%d"},
526 {Opt_force, "force=%d"},
527 {Opt_err, NULL}
528};
529
530static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
531 const char *page, ssize_t count)
532{
533 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
534 char *orig, *ptr, *arg_p, *opts;
535 substring_t args[MAX_OPT_ARGS];
536 int ret = 0, token;
537 unsigned long tmp_readonly;
538
539 opts = kstrdup(page, GFP_KERNEL);
540 if (!opts)
541 return -ENOMEM;
542
543 orig = opts;
544
545 while ((ptr = strsep(&opts, ",\n")) != NULL) {
546 if (!*ptr)
547 continue;
548
549 token = match_token(ptr, tokens, args);
550 switch (token) {
551 case Opt_udev_path:
552 if (ib_dev->ibd_bd) {
553 pr_err("Unable to set udev_path= while"
554 " ib_dev->ibd_bd exists\n");
555 ret = -EEXIST;
556 goto out;
557 }
558 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
559 SE_UDEV_PATH_LEN) == 0) {
560 ret = -EINVAL;
561 break;
562 }
563 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
564 ib_dev->ibd_udev_path);
565 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
566 break;
567 case Opt_readonly:
568 arg_p = match_strdup(&args[0]);
569 if (!arg_p) {
570 ret = -ENOMEM;
571 break;
572 }
573 ret = kstrtoul(arg_p, 0, &tmp_readonly);
574 kfree(arg_p);
575 if (ret < 0) {
576 pr_err("kstrtoul() failed for"
577 " readonly=\n");
578 goto out;
579 }
580 ib_dev->ibd_readonly = tmp_readonly;
581 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
582 break;
583 case Opt_force:
584 break;
585 default:
586 break;
587 }
588 }
589
590out:
591 kfree(orig);
592 return (!ret) ? count : ret;
593}
594
595static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
596{
597 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
598 struct block_device *bd = ib_dev->ibd_bd;
599 char buf[BDEVNAME_SIZE];
600 ssize_t bl = 0;
601
602 if (bd)
603 bl += sprintf(b + bl, "iBlock device: %s",
604 bdevname(bd, buf));
605 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
606 bl += sprintf(b + bl, " UDEV PATH: %s",
607 ib_dev->ibd_udev_path);
608 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly);
609
610 bl += sprintf(b + bl, " ");
611 if (bd) {
612 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
613 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
614 "" : (bd->bd_holder == ib_dev) ?
615 "CLAIMED: IBLOCK" : "CLAIMED: OS");
616 } else {
617 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
618 }
619
620 return bl;
621}
622
623static int
624iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio)
625{
626 struct se_device *dev = cmd->se_dev;
627 struct blk_integrity *bi;
628 struct bio_integrity_payload *bip;
629 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
630 struct scatterlist *sg;
631 int i, rc;
632
633 bi = bdev_get_integrity(ib_dev->ibd_bd);
634 if (!bi) {
635 pr_err("Unable to locate bio_integrity\n");
636 return -ENODEV;
637 }
638
639 bip = bio_integrity_alloc(bio, GFP_NOIO, cmd->t_prot_nents);
640 if (!bip) {
641 pr_err("Unable to allocate bio_integrity_payload\n");
642 return -ENOMEM;
643 }
644
645 bip->bip_iter.bi_size = (cmd->data_length / dev->dev_attrib.block_size) *
646 dev->prot_length;
647 bip->bip_iter.bi_sector = bio->bi_iter.bi_sector;
648
649 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size,
650 (unsigned long long)bip->bip_iter.bi_sector);
651
652 for_each_sg(cmd->t_prot_sg, sg, cmd->t_prot_nents, i) {
653
654 rc = bio_integrity_add_page(bio, sg_page(sg), sg->length,
655 sg->offset);
656 if (rc != sg->length) {
657 pr_err("bio_integrity_add_page() failed; %d\n", rc);
658 return -ENOMEM;
659 }
660
661 pr_debug("Added bio integrity page: %p length: %d offset; %d\n",
662 sg_page(sg), sg->length, sg->offset);
663 }
664
665 return 0;
666}
667
668static sense_reason_t
669iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
670 enum dma_data_direction data_direction)
671{
672 struct se_device *dev = cmd->se_dev;
673 struct iblock_req *ibr;
674 struct bio *bio, *bio_start;
675 struct bio_list list;
676 struct scatterlist *sg;
677 u32 sg_num = sgl_nents;
678 sector_t block_lba;
679 unsigned bio_cnt;
680 int rw = 0;
681 int i;
682
683 if (data_direction == DMA_TO_DEVICE) {
684 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
685 struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd);
686 /*
687 * Force writethrough using WRITE_FUA if a volatile write cache
688 * is not enabled, or if initiator set the Force Unit Access bit.
689 */
690 if (q->flush_flags & REQ_FUA) {
691 if (cmd->se_cmd_flags & SCF_FUA)
692 rw = WRITE_FUA;
693 else if (!(q->flush_flags & REQ_FLUSH))
694 rw = WRITE_FUA;
695 else
696 rw = WRITE;
697 } else {
698 rw = WRITE;
699 }
700 } else {
701 rw = READ;
702 }
703
704 /*
705 * Convert the blocksize advertised to the initiator to the 512 byte
706 * units unconditionally used by the Linux block layer.
707 */
708 if (dev->dev_attrib.block_size == 4096)
709 block_lba = (cmd->t_task_lba << 3);
710 else if (dev->dev_attrib.block_size == 2048)
711 block_lba = (cmd->t_task_lba << 2);
712 else if (dev->dev_attrib.block_size == 1024)
713 block_lba = (cmd->t_task_lba << 1);
714 else if (dev->dev_attrib.block_size == 512)
715 block_lba = cmd->t_task_lba;
716 else {
717 pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
718 " %u\n", dev->dev_attrib.block_size);
719 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
720 }
721
722 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
723 if (!ibr)
724 goto fail;
725 cmd->priv = ibr;
726
727 if (!sgl_nents) {
728 atomic_set(&ibr->pending, 1);
729 iblock_complete_cmd(cmd);
730 return 0;
731 }
732
733 bio = iblock_get_bio(cmd, block_lba, sgl_nents);
734 if (!bio)
735 goto fail_free_ibr;
736
737 bio_start = bio;
738 bio_list_init(&list);
739 bio_list_add(&list, bio);
740
741 atomic_set(&ibr->pending, 2);
742 bio_cnt = 1;
743
744 for_each_sg(sgl, sg, sgl_nents, i) {
745 /*
746 * XXX: if the length the device accepts is shorter than the
747 * length of the S/G list entry this will cause and
748 * endless loop. Better hope no driver uses huge pages.
749 */
750 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
751 != sg->length) {
752 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
753 iblock_submit_bios(&list, rw);
754 bio_cnt = 0;
755 }
756
757 bio = iblock_get_bio(cmd, block_lba, sg_num);
758 if (!bio)
759 goto fail_put_bios;
760
761 atomic_inc(&ibr->pending);
762 bio_list_add(&list, bio);
763 bio_cnt++;
764 }
765
766 /* Always in 512 byte units for Linux/Block */
767 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
768 sg_num--;
769 }
770
771 if (cmd->prot_type) {
772 int rc = iblock_alloc_bip(cmd, bio_start);
773 if (rc)
774 goto fail_put_bios;
775 }
776
777 iblock_submit_bios(&list, rw);
778 iblock_complete_cmd(cmd);
779 return 0;
780
781fail_put_bios:
782 while ((bio = bio_list_pop(&list)))
783 bio_put(bio);
784fail_free_ibr:
785 kfree(ibr);
786fail:
787 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
788}
789
790static sector_t iblock_get_blocks(struct se_device *dev)
791{
792 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
793 struct block_device *bd = ib_dev->ibd_bd;
794 struct request_queue *q = bdev_get_queue(bd);
795
796 return iblock_emulate_read_cap_with_block_size(dev, bd, q);
797}
798
799static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev)
800{
801 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
802 struct block_device *bd = ib_dev->ibd_bd;
803 int ret;
804
805 ret = bdev_alignment_offset(bd);
806 if (ret == -1)
807 return 0;
808
809 /* convert offset-bytes to offset-lbas */
810 return ret / bdev_logical_block_size(bd);
811}
812
813static unsigned int iblock_get_lbppbe(struct se_device *dev)
814{
815 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
816 struct block_device *bd = ib_dev->ibd_bd;
817 int logs_per_phys = bdev_physical_block_size(bd) / bdev_logical_block_size(bd);
818
819 return ilog2(logs_per_phys);
820}
821
822static unsigned int iblock_get_io_min(struct se_device *dev)
823{
824 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
825 struct block_device *bd = ib_dev->ibd_bd;
826
827 return bdev_io_min(bd);
828}
829
830static unsigned int iblock_get_io_opt(struct se_device *dev)
831{
832 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
833 struct block_device *bd = ib_dev->ibd_bd;
834
835 return bdev_io_opt(bd);
836}
837
838static struct sbc_ops iblock_sbc_ops = {
839 .execute_rw = iblock_execute_rw,
840 .execute_sync_cache = iblock_execute_sync_cache,
841 .execute_write_same = iblock_execute_write_same,
842 .execute_write_same_unmap = iblock_execute_write_same_unmap,
843 .execute_unmap = iblock_execute_unmap,
844};
845
846static sense_reason_t
847iblock_parse_cdb(struct se_cmd *cmd)
848{
849 return sbc_parse_cdb(cmd, &iblock_sbc_ops);
850}
851
852static bool iblock_get_write_cache(struct se_device *dev)
853{
854 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
855 struct block_device *bd = ib_dev->ibd_bd;
856 struct request_queue *q = bdev_get_queue(bd);
857
858 return q->flush_flags & REQ_FLUSH;
859}
860
861static struct se_subsystem_api iblock_template = {
862 .name = "iblock",
863 .inquiry_prod = "IBLOCK",
864 .inquiry_rev = IBLOCK_VERSION,
865 .owner = THIS_MODULE,
866 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
867 .attach_hba = iblock_attach_hba,
868 .detach_hba = iblock_detach_hba,
869 .alloc_device = iblock_alloc_device,
870 .configure_device = iblock_configure_device,
871 .free_device = iblock_free_device,
872 .parse_cdb = iblock_parse_cdb,
873 .set_configfs_dev_params = iblock_set_configfs_dev_params,
874 .show_configfs_dev_params = iblock_show_configfs_dev_params,
875 .get_device_type = sbc_get_device_type,
876 .get_blocks = iblock_get_blocks,
877 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas,
878 .get_lbppbe = iblock_get_lbppbe,
879 .get_io_min = iblock_get_io_min,
880 .get_io_opt = iblock_get_io_opt,
881 .get_write_cache = iblock_get_write_cache,
882};
883
884static int __init iblock_module_init(void)
885{
886 return transport_subsystem_register(&iblock_template);
887}
888
889static void __exit iblock_module_exit(void)
890{
891 transport_subsystem_release(&iblock_template);
892}
893
894MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
895MODULE_AUTHOR("nab@Linux-iSCSI.org");
896MODULE_LICENSE("GPL");
897
898module_init(iblock_module_init);
899module_exit(iblock_module_exit);