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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 <asm/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 bdev_handle *bdev_handle;
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_handle = bdev_open_by_path(ib_dev->ibd_udev_path, mode, ib_dev,
121 NULL);
122 if (IS_ERR(bdev_handle)) {
123 ret = PTR_ERR(bdev_handle);
124 goto out_free_bioset;
125 }
126 ib_dev->ibd_bdev_handle = bdev_handle;
127 ib_dev->ibd_bd = bd = bdev_handle->bdev;
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 struct bio_set *bs = &ib_dev->ibd_bio_set;
153
154 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-IP") ||
155 !strcmp(bi->profile->name, "T10-DIF-TYPE1-IP")) {
156 pr_err("IBLOCK export of blk_integrity: %s not"
157 " supported\n", bi->profile->name);
158 ret = -ENOSYS;
159 goto out_blkdev_put;
160 }
161
162 if (!strcmp(bi->profile->name, "T10-DIF-TYPE3-CRC")) {
163 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
164 } else if (!strcmp(bi->profile->name, "T10-DIF-TYPE1-CRC")) {
165 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
166 }
167
168 if (dev->dev_attrib.pi_prot_type) {
169 if (bioset_integrity_create(bs, IBLOCK_BIO_POOL_SIZE) < 0) {
170 pr_err("Unable to allocate bioset for PI\n");
171 ret = -ENOMEM;
172 goto out_blkdev_put;
173 }
174 pr_debug("IBLOCK setup BIP bs->bio_integrity_pool: %p\n",
175 &bs->bio_integrity_pool);
176 }
177 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
178 }
179
180 return 0;
181
182out_blkdev_put:
183 bdev_release(ib_dev->ibd_bdev_handle);
184out_free_bioset:
185 bioset_exit(&ib_dev->ibd_bio_set);
186out:
187 return ret;
188}
189
190static void iblock_dev_call_rcu(struct rcu_head *p)
191{
192 struct se_device *dev = container_of(p, struct se_device, rcu_head);
193 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
194
195 kfree(ib_dev->ibd_plug);
196 kfree(ib_dev);
197}
198
199static void iblock_free_device(struct se_device *dev)
200{
201 call_rcu(&dev->rcu_head, iblock_dev_call_rcu);
202}
203
204static void iblock_destroy_device(struct se_device *dev)
205{
206 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
207
208 if (ib_dev->ibd_bdev_handle)
209 bdev_release(ib_dev->ibd_bdev_handle);
210 bioset_exit(&ib_dev->ibd_bio_set);
211}
212
213static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev)
214{
215 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev);
216 struct iblock_dev_plug *ib_dev_plug;
217
218 /*
219 * Each se_device has a per cpu work this can be run from. We
220 * shouldn't have multiple threads on the same cpu calling this
221 * at the same time.
222 */
223 ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()];
224 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags))
225 return NULL;
226
227 blk_start_plug(&ib_dev_plug->blk_plug);
228 return &ib_dev_plug->se_plug;
229}
230
231static void iblock_unplug_device(struct se_dev_plug *se_plug)
232{
233 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug,
234 struct iblock_dev_plug, se_plug);
235
236 blk_finish_plug(&ib_dev_plug->blk_plug);
237 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags);
238}
239
240static sector_t iblock_get_blocks(struct se_device *dev)
241{
242 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
243 u32 block_size = bdev_logical_block_size(ib_dev->ibd_bd);
244 unsigned long long blocks_long =
245 div_u64(bdev_nr_bytes(ib_dev->ibd_bd), block_size) - 1;
246
247 if (block_size == dev->dev_attrib.block_size)
248 return blocks_long;
249
250 switch (block_size) {
251 case 4096:
252 switch (dev->dev_attrib.block_size) {
253 case 2048:
254 blocks_long <<= 1;
255 break;
256 case 1024:
257 blocks_long <<= 2;
258 break;
259 case 512:
260 blocks_long <<= 3;
261 break;
262 default:
263 break;
264 }
265 break;
266 case 2048:
267 switch (dev->dev_attrib.block_size) {
268 case 4096:
269 blocks_long >>= 1;
270 break;
271 case 1024:
272 blocks_long <<= 1;
273 break;
274 case 512:
275 blocks_long <<= 2;
276 break;
277 default:
278 break;
279 }
280 break;
281 case 1024:
282 switch (dev->dev_attrib.block_size) {
283 case 4096:
284 blocks_long >>= 2;
285 break;
286 case 2048:
287 blocks_long >>= 1;
288 break;
289 case 512:
290 blocks_long <<= 1;
291 break;
292 default:
293 break;
294 }
295 break;
296 case 512:
297 switch (dev->dev_attrib.block_size) {
298 case 4096:
299 blocks_long >>= 3;
300 break;
301 case 2048:
302 blocks_long >>= 2;
303 break;
304 case 1024:
305 blocks_long >>= 1;
306 break;
307 default:
308 break;
309 }
310 break;
311 default:
312 break;
313 }
314
315 return blocks_long;
316}
317
318static void iblock_complete_cmd(struct se_cmd *cmd, blk_status_t blk_status)
319{
320 struct iblock_req *ibr = cmd->priv;
321 u8 status;
322
323 if (!refcount_dec_and_test(&ibr->pending))
324 return;
325
326 if (blk_status == BLK_STS_RESV_CONFLICT)
327 status = SAM_STAT_RESERVATION_CONFLICT;
328 else if (atomic_read(&ibr->ib_bio_err_cnt))
329 status = SAM_STAT_CHECK_CONDITION;
330 else
331 status = SAM_STAT_GOOD;
332
333 target_complete_cmd(cmd, status);
334 kfree(ibr);
335}
336
337static void iblock_bio_done(struct bio *bio)
338{
339 struct se_cmd *cmd = bio->bi_private;
340 struct iblock_req *ibr = cmd->priv;
341 blk_status_t blk_status = bio->bi_status;
342
343 if (bio->bi_status) {
344 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status);
345 /*
346 * Bump the ib_bio_err_cnt and release bio.
347 */
348 atomic_inc(&ibr->ib_bio_err_cnt);
349 smp_mb__after_atomic();
350 }
351
352 bio_put(bio);
353
354 iblock_complete_cmd(cmd, blk_status);
355}
356
357static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num,
358 blk_opf_t opf)
359{
360 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
361 struct bio *bio;
362
363 /*
364 * Only allocate as many vector entries as the bio code allows us to,
365 * we'll loop later on until we have handled the whole request.
366 */
367 bio = bio_alloc_bioset(ib_dev->ibd_bd, bio_max_segs(sg_num), opf,
368 GFP_NOIO, &ib_dev->ibd_bio_set);
369 if (!bio) {
370 pr_err("Unable to allocate memory for bio\n");
371 return NULL;
372 }
373
374 bio->bi_private = cmd;
375 bio->bi_end_io = &iblock_bio_done;
376 bio->bi_iter.bi_sector = lba;
377
378 return bio;
379}
380
381static void iblock_submit_bios(struct bio_list *list)
382{
383 struct blk_plug plug;
384 struct bio *bio;
385 /*
386 * The block layer handles nested plugs, so just plug/unplug to handle
387 * fabric drivers that didn't support batching and multi bio cmds.
388 */
389 blk_start_plug(&plug);
390 while ((bio = bio_list_pop(list)))
391 submit_bio(bio);
392 blk_finish_plug(&plug);
393}
394
395static void iblock_end_io_flush(struct bio *bio)
396{
397 struct se_cmd *cmd = bio->bi_private;
398
399 if (bio->bi_status)
400 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status);
401
402 if (cmd) {
403 if (bio->bi_status)
404 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
405 else
406 target_complete_cmd(cmd, SAM_STAT_GOOD);
407 }
408
409 bio_put(bio);
410}
411
412/*
413 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
414 * always flush the whole cache.
415 */
416static sense_reason_t
417iblock_execute_sync_cache(struct se_cmd *cmd)
418{
419 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
420 int immed = (cmd->t_task_cdb[1] & 0x2);
421 struct bio *bio;
422
423 /*
424 * If the Immediate bit is set, queue up the GOOD response
425 * for this SYNCHRONIZE_CACHE op.
426 */
427 if (immed)
428 target_complete_cmd(cmd, SAM_STAT_GOOD);
429
430 bio = bio_alloc(ib_dev->ibd_bd, 0, REQ_OP_WRITE | REQ_PREFLUSH,
431 GFP_KERNEL);
432 bio->bi_end_io = iblock_end_io_flush;
433 if (!immed)
434 bio->bi_private = cmd;
435 submit_bio(bio);
436 return 0;
437}
438
439static sense_reason_t
440iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
441{
442 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
443 struct se_device *dev = cmd->se_dev;
444 int ret;
445
446 ret = blkdev_issue_discard(bdev,
447 target_to_linux_sector(dev, lba),
448 target_to_linux_sector(dev, nolb),
449 GFP_KERNEL);
450 if (ret < 0) {
451 pr_err("blkdev_issue_discard() failed: %d\n", ret);
452 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
453 }
454
455 return 0;
456}
457
458static sense_reason_t
459iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd)
460{
461 struct se_device *dev = cmd->se_dev;
462 struct scatterlist *sg = &cmd->t_data_sg[0];
463 unsigned char *buf, *not_zero;
464 int ret;
465
466 buf = kmap(sg_page(sg)) + sg->offset;
467 if (!buf)
468 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
469 /*
470 * Fall back to block_execute_write_same() slow-path if
471 * incoming WRITE_SAME payload does not contain zeros.
472 */
473 not_zero = memchr_inv(buf, 0x00, cmd->data_length);
474 kunmap(sg_page(sg));
475
476 if (not_zero)
477 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
478
479 ret = blkdev_issue_zeroout(bdev,
480 target_to_linux_sector(dev, cmd->t_task_lba),
481 target_to_linux_sector(dev,
482 sbc_get_write_same_sectors(cmd)),
483 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
484 if (ret)
485 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
486
487 target_complete_cmd(cmd, SAM_STAT_GOOD);
488 return 0;
489}
490
491static sense_reason_t
492iblock_execute_write_same(struct se_cmd *cmd)
493{
494 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
495 struct iblock_req *ibr;
496 struct scatterlist *sg;
497 struct bio *bio;
498 struct bio_list list;
499 struct se_device *dev = cmd->se_dev;
500 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
501 sector_t sectors = target_to_linux_sector(dev,
502 sbc_get_write_same_sectors(cmd));
503
504 if (cmd->prot_op) {
505 pr_err("WRITE_SAME: Protection information with IBLOCK"
506 " backends not supported\n");
507 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
508 }
509
510 if (!cmd->t_data_nents)
511 return TCM_INVALID_CDB_FIELD;
512
513 sg = &cmd->t_data_sg[0];
514
515 if (cmd->t_data_nents > 1 ||
516 sg->length != cmd->se_dev->dev_attrib.block_size) {
517 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
518 " block_size: %u\n", cmd->t_data_nents, sg->length,
519 cmd->se_dev->dev_attrib.block_size);
520 return TCM_INVALID_CDB_FIELD;
521 }
522
523 if (bdev_write_zeroes_sectors(bdev)) {
524 if (!iblock_execute_zero_out(bdev, cmd))
525 return 0;
526 }
527
528 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
529 if (!ibr)
530 goto fail;
531 cmd->priv = ibr;
532
533 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
534 if (!bio)
535 goto fail_free_ibr;
536
537 bio_list_init(&list);
538 bio_list_add(&list, bio);
539
540 refcount_set(&ibr->pending, 1);
541
542 while (sectors) {
543 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
544 != sg->length) {
545
546 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
547 if (!bio)
548 goto fail_put_bios;
549
550 refcount_inc(&ibr->pending);
551 bio_list_add(&list, bio);
552 }
553
554 /* Always in 512 byte units for Linux/Block */
555 block_lba += sg->length >> SECTOR_SHIFT;
556 sectors -= sg->length >> SECTOR_SHIFT;
557 }
558
559 iblock_submit_bios(&list);
560 return 0;
561
562fail_put_bios:
563 while ((bio = bio_list_pop(&list)))
564 bio_put(bio);
565fail_free_ibr:
566 kfree(ibr);
567fail:
568 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
569}
570
571enum {
572 Opt_udev_path, Opt_readonly, Opt_force, Opt_err
573};
574
575static match_table_t tokens = {
576 {Opt_udev_path, "udev_path=%s"},
577 {Opt_readonly, "readonly=%d"},
578 {Opt_force, "force=%d"},
579 {Opt_err, NULL}
580};
581
582static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
583 const char *page, ssize_t count)
584{
585 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
586 char *orig, *ptr, *arg_p, *opts;
587 substring_t args[MAX_OPT_ARGS];
588 int ret = 0, token;
589 unsigned long tmp_readonly;
590
591 opts = kstrdup(page, GFP_KERNEL);
592 if (!opts)
593 return -ENOMEM;
594
595 orig = opts;
596
597 while ((ptr = strsep(&opts, ",\n")) != NULL) {
598 if (!*ptr)
599 continue;
600
601 token = match_token(ptr, tokens, args);
602 switch (token) {
603 case Opt_udev_path:
604 if (ib_dev->ibd_bd) {
605 pr_err("Unable to set udev_path= while"
606 " ib_dev->ibd_bd exists\n");
607 ret = -EEXIST;
608 goto out;
609 }
610 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
611 SE_UDEV_PATH_LEN) == 0) {
612 ret = -EINVAL;
613 break;
614 }
615 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
616 ib_dev->ibd_udev_path);
617 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
618 break;
619 case Opt_readonly:
620 arg_p = match_strdup(&args[0]);
621 if (!arg_p) {
622 ret = -ENOMEM;
623 break;
624 }
625 ret = kstrtoul(arg_p, 0, &tmp_readonly);
626 kfree(arg_p);
627 if (ret < 0) {
628 pr_err("kstrtoul() failed for"
629 " readonly=\n");
630 goto out;
631 }
632 ib_dev->ibd_readonly = tmp_readonly;
633 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
634 break;
635 case Opt_force:
636 break;
637 default:
638 break;
639 }
640 }
641
642out:
643 kfree(orig);
644 return (!ret) ? count : ret;
645}
646
647static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
648{
649 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
650 struct block_device *bd = ib_dev->ibd_bd;
651 ssize_t bl = 0;
652
653 if (bd)
654 bl += sprintf(b + bl, "iBlock device: %pg", bd);
655 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
656 bl += sprintf(b + bl, " UDEV PATH: %s",
657 ib_dev->ibd_udev_path);
658 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly);
659
660 bl += sprintf(b + bl, " ");
661 if (bd) {
662 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
663 MAJOR(bd->bd_dev), MINOR(bd->bd_dev),
664 "CLAIMED: IBLOCK");
665 } else {
666 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
667 }
668
669 return bl;
670}
671
672static int
673iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio,
674 struct sg_mapping_iter *miter)
675{
676 struct se_device *dev = cmd->se_dev;
677 struct blk_integrity *bi;
678 struct bio_integrity_payload *bip;
679 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
680 int rc;
681 size_t resid, len;
682
683 bi = bdev_get_integrity(ib_dev->ibd_bd);
684 if (!bi) {
685 pr_err("Unable to locate bio_integrity\n");
686 return -ENODEV;
687 }
688
689 bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents));
690 if (IS_ERR(bip)) {
691 pr_err("Unable to allocate bio_integrity_payload\n");
692 return PTR_ERR(bip);
693 }
694
695 /* virtual start sector must be in integrity interval units */
696 bip_set_seed(bip, bio->bi_iter.bi_sector >>
697 (bi->interval_exp - SECTOR_SHIFT));
698
699 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size,
700 (unsigned long long)bip->bip_iter.bi_sector);
701
702 resid = bio_integrity_bytes(bi, bio_sectors(bio));
703 while (resid > 0 && sg_miter_next(miter)) {
704
705 len = min_t(size_t, miter->length, resid);
706 rc = bio_integrity_add_page(bio, miter->page, len,
707 offset_in_page(miter->addr));
708 if (rc != len) {
709 pr_err("bio_integrity_add_page() failed; %d\n", rc);
710 sg_miter_stop(miter);
711 return -ENOMEM;
712 }
713
714 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n",
715 miter->page, len, offset_in_page(miter->addr));
716
717 resid -= len;
718 if (len < miter->length)
719 miter->consumed -= miter->length - len;
720 }
721 sg_miter_stop(miter);
722
723 return 0;
724}
725
726static sense_reason_t
727iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
728 enum dma_data_direction data_direction)
729{
730 struct se_device *dev = cmd->se_dev;
731 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
732 struct iblock_req *ibr;
733 struct bio *bio;
734 struct bio_list list;
735 struct scatterlist *sg;
736 u32 sg_num = sgl_nents;
737 blk_opf_t opf;
738 unsigned bio_cnt;
739 int i, rc;
740 struct sg_mapping_iter prot_miter;
741 unsigned int miter_dir;
742
743 if (data_direction == DMA_TO_DEVICE) {
744 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
745
746 /*
747 * Set bits to indicate WRITE_ODIRECT so we are not throttled
748 * by WBT.
749 */
750 opf = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
751 /*
752 * Force writethrough using REQ_FUA if a volatile write cache
753 * is not enabled, or if initiator set the Force Unit Access bit.
754 */
755 miter_dir = SG_MITER_TO_SG;
756 if (bdev_fua(ib_dev->ibd_bd)) {
757 if (cmd->se_cmd_flags & SCF_FUA)
758 opf |= REQ_FUA;
759 else if (!bdev_write_cache(ib_dev->ibd_bd))
760 opf |= REQ_FUA;
761 }
762 } else {
763 opf = REQ_OP_READ;
764 miter_dir = SG_MITER_FROM_SG;
765 }
766
767 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
768 if (!ibr)
769 goto fail;
770 cmd->priv = ibr;
771
772 if (!sgl_nents) {
773 refcount_set(&ibr->pending, 1);
774 iblock_complete_cmd(cmd, BLK_STS_OK);
775 return 0;
776 }
777
778 bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf);
779 if (!bio)
780 goto fail_free_ibr;
781
782 bio_list_init(&list);
783 bio_list_add(&list, bio);
784
785 refcount_set(&ibr->pending, 2);
786 bio_cnt = 1;
787
788 if (cmd->prot_type && dev->dev_attrib.pi_prot_type)
789 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents,
790 miter_dir);
791
792 for_each_sg(sgl, sg, sgl_nents, i) {
793 /*
794 * XXX: if the length the device accepts is shorter than the
795 * length of the S/G list entry this will cause and
796 * endless loop. Better hope no driver uses huge pages.
797 */
798 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
799 != sg->length) {
800 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
801 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
802 if (rc)
803 goto fail_put_bios;
804 }
805
806 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
807 iblock_submit_bios(&list);
808 bio_cnt = 0;
809 }
810
811 bio = iblock_get_bio(cmd, block_lba, sg_num, opf);
812 if (!bio)
813 goto fail_put_bios;
814
815 refcount_inc(&ibr->pending);
816 bio_list_add(&list, bio);
817 bio_cnt++;
818 }
819
820 /* Always in 512 byte units for Linux/Block */
821 block_lba += sg->length >> SECTOR_SHIFT;
822 sg_num--;
823 }
824
825 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
826 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
827 if (rc)
828 goto fail_put_bios;
829 }
830
831 iblock_submit_bios(&list);
832 iblock_complete_cmd(cmd, BLK_STS_OK);
833 return 0;
834
835fail_put_bios:
836 while ((bio = bio_list_pop(&list)))
837 bio_put(bio);
838fail_free_ibr:
839 kfree(ibr);
840fail:
841 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
842}
843
844static sense_reason_t iblock_execute_pr_out(struct se_cmd *cmd, u8 sa, u64 key,
845 u64 sa_key, u8 type, bool aptpl)
846{
847 struct se_device *dev = cmd->se_dev;
848 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
849 struct block_device *bdev = ib_dev->ibd_bd;
850 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
851 int ret;
852
853 if (!ops) {
854 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
855 return TCM_UNSUPPORTED_SCSI_OPCODE;
856 }
857
858 switch (sa) {
859 case PRO_REGISTER:
860 case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
861 if (!ops->pr_register) {
862 pr_err("block device does not support pr_register.\n");
863 return TCM_UNSUPPORTED_SCSI_OPCODE;
864 }
865
866 /* The block layer pr ops always enables aptpl */
867 if (!aptpl)
868 pr_info("APTPL not set by initiator, but will be used.\n");
869
870 ret = ops->pr_register(bdev, key, sa_key,
871 sa == PRO_REGISTER ? 0 : PR_FL_IGNORE_KEY);
872 break;
873 case PRO_RESERVE:
874 if (!ops->pr_reserve) {
875 pr_err("block_device does not support pr_reserve.\n");
876 return TCM_UNSUPPORTED_SCSI_OPCODE;
877 }
878
879 ret = ops->pr_reserve(bdev, key, scsi_pr_type_to_block(type), 0);
880 break;
881 case PRO_CLEAR:
882 if (!ops->pr_clear) {
883 pr_err("block_device does not support pr_clear.\n");
884 return TCM_UNSUPPORTED_SCSI_OPCODE;
885 }
886
887 ret = ops->pr_clear(bdev, key);
888 break;
889 case PRO_PREEMPT:
890 case PRO_PREEMPT_AND_ABORT:
891 if (!ops->pr_clear) {
892 pr_err("block_device does not support pr_preempt.\n");
893 return TCM_UNSUPPORTED_SCSI_OPCODE;
894 }
895
896 ret = ops->pr_preempt(bdev, key, sa_key,
897 scsi_pr_type_to_block(type),
898 sa == PRO_PREEMPT_AND_ABORT);
899 break;
900 case PRO_RELEASE:
901 if (!ops->pr_clear) {
902 pr_err("block_device does not support pr_pclear.\n");
903 return TCM_UNSUPPORTED_SCSI_OPCODE;
904 }
905
906 ret = ops->pr_release(bdev, key, scsi_pr_type_to_block(type));
907 break;
908 default:
909 pr_err("Unknown PERSISTENT_RESERVE_OUT SA: 0x%02x\n", sa);
910 return TCM_UNSUPPORTED_SCSI_OPCODE;
911 }
912
913 if (!ret)
914 return TCM_NO_SENSE;
915 else if (ret == PR_STS_RESERVATION_CONFLICT)
916 return TCM_RESERVATION_CONFLICT;
917 else
918 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
919}
920
921static void iblock_pr_report_caps(unsigned char *param_data)
922{
923 u16 len = 8;
924
925 put_unaligned_be16(len, ¶m_data[0]);
926 /*
927 * When using the pr_ops passthrough method we only support exporting
928 * the device through one target port because from the backend module
929 * level we can't see the target port config. As a result we only
930 * support registration directly from the I_T nexus the cmd is sent
931 * through and do not set ATP_C here.
932 *
933 * The block layer pr_ops do not support passing in initiators so
934 * we don't set SIP_C here.
935 */
936 /* PTPL_C: Persistence across Target Power Loss bit */
937 param_data[2] |= 0x01;
938 /*
939 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
940 * set the TMV: Task Mask Valid bit.
941 */
942 param_data[3] |= 0x80;
943 /*
944 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
945 */
946 param_data[3] |= 0x10; /* ALLOW COMMANDs field 001b */
947 /*
948 * PTPL_A: Persistence across Target Power Loss Active bit. The block
949 * layer pr ops always enables this so report it active.
950 */
951 param_data[3] |= 0x01;
952 /*
953 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 212 spc4r37.
954 */
955 param_data[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
956 param_data[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
957 param_data[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
958 param_data[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
959 param_data[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
960 param_data[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
961}
962
963static sense_reason_t iblock_pr_read_keys(struct se_cmd *cmd,
964 unsigned char *param_data)
965{
966 struct se_device *dev = cmd->se_dev;
967 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
968 struct block_device *bdev = ib_dev->ibd_bd;
969 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
970 int i, len, paths, data_offset;
971 struct pr_keys *keys;
972 sense_reason_t ret;
973
974 if (!ops) {
975 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
976 return TCM_UNSUPPORTED_SCSI_OPCODE;
977 }
978
979 if (!ops->pr_read_keys) {
980 pr_err("Block device does not support read_keys.\n");
981 return TCM_UNSUPPORTED_SCSI_OPCODE;
982 }
983
984 /*
985 * We don't know what's under us, but dm-multipath will register every
986 * path with the same key, so start off with enough space for 16 paths.
987 * which is not a lot of memory and should normally be enough.
988 */
989 paths = 16;
990retry:
991 len = 8 * paths;
992 keys = kzalloc(sizeof(*keys) + len, GFP_KERNEL);
993 if (!keys)
994 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
995
996 keys->num_keys = paths;
997 if (!ops->pr_read_keys(bdev, keys)) {
998 if (keys->num_keys > paths) {
999 kfree(keys);
1000 paths *= 2;
1001 goto retry;
1002 }
1003 } else {
1004 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1005 goto free_keys;
1006 }
1007
1008 ret = TCM_NO_SENSE;
1009
1010 put_unaligned_be32(keys->generation, ¶m_data[0]);
1011 if (!keys->num_keys) {
1012 put_unaligned_be32(0, ¶m_data[4]);
1013 goto free_keys;
1014 }
1015
1016 put_unaligned_be32(8 * keys->num_keys, ¶m_data[4]);
1017
1018 data_offset = 8;
1019 for (i = 0; i < keys->num_keys; i++) {
1020 if (data_offset + 8 > cmd->data_length)
1021 break;
1022
1023 put_unaligned_be64(keys->keys[i], ¶m_data[data_offset]);
1024 data_offset += 8;
1025 }
1026
1027free_keys:
1028 kfree(keys);
1029 return ret;
1030}
1031
1032static sense_reason_t iblock_pr_read_reservation(struct se_cmd *cmd,
1033 unsigned char *param_data)
1034{
1035 struct se_device *dev = cmd->se_dev;
1036 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1037 struct block_device *bdev = ib_dev->ibd_bd;
1038 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
1039 struct pr_held_reservation rsv = { };
1040
1041 if (!ops) {
1042 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
1043 return TCM_UNSUPPORTED_SCSI_OPCODE;
1044 }
1045
1046 if (!ops->pr_read_reservation) {
1047 pr_err("Block device does not support read_keys.\n");
1048 return TCM_UNSUPPORTED_SCSI_OPCODE;
1049 }
1050
1051 if (ops->pr_read_reservation(bdev, &rsv))
1052 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1053
1054 put_unaligned_be32(rsv.generation, ¶m_data[0]);
1055 if (!block_pr_type_to_scsi(rsv.type)) {
1056 put_unaligned_be32(0, ¶m_data[4]);
1057 return TCM_NO_SENSE;
1058 }
1059
1060 put_unaligned_be32(16, ¶m_data[4]);
1061
1062 if (cmd->data_length < 16)
1063 return TCM_NO_SENSE;
1064 put_unaligned_be64(rsv.key, ¶m_data[8]);
1065
1066 if (cmd->data_length < 22)
1067 return TCM_NO_SENSE;
1068 param_data[21] = block_pr_type_to_scsi(rsv.type);
1069
1070 return TCM_NO_SENSE;
1071}
1072
1073static sense_reason_t iblock_execute_pr_in(struct se_cmd *cmd, u8 sa,
1074 unsigned char *param_data)
1075{
1076 sense_reason_t ret = TCM_NO_SENSE;
1077
1078 switch (sa) {
1079 case PRI_REPORT_CAPABILITIES:
1080 iblock_pr_report_caps(param_data);
1081 break;
1082 case PRI_READ_KEYS:
1083 ret = iblock_pr_read_keys(cmd, param_data);
1084 break;
1085 case PRI_READ_RESERVATION:
1086 ret = iblock_pr_read_reservation(cmd, param_data);
1087 break;
1088 default:
1089 pr_err("Unknown PERSISTENT_RESERVE_IN SA: 0x%02x\n", sa);
1090 return TCM_UNSUPPORTED_SCSI_OPCODE;
1091 }
1092
1093 return ret;
1094}
1095
1096static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev)
1097{
1098 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1099 struct block_device *bd = ib_dev->ibd_bd;
1100 int ret;
1101
1102 ret = bdev_alignment_offset(bd);
1103 if (ret == -1)
1104 return 0;
1105
1106 /* convert offset-bytes to offset-lbas */
1107 return ret / bdev_logical_block_size(bd);
1108}
1109
1110static unsigned int iblock_get_lbppbe(struct se_device *dev)
1111{
1112 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1113 struct block_device *bd = ib_dev->ibd_bd;
1114 unsigned int logs_per_phys =
1115 bdev_physical_block_size(bd) / bdev_logical_block_size(bd);
1116
1117 return ilog2(logs_per_phys);
1118}
1119
1120static unsigned int iblock_get_io_min(struct se_device *dev)
1121{
1122 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1123 struct block_device *bd = ib_dev->ibd_bd;
1124
1125 return bdev_io_min(bd);
1126}
1127
1128static unsigned int iblock_get_io_opt(struct se_device *dev)
1129{
1130 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1131 struct block_device *bd = ib_dev->ibd_bd;
1132
1133 return bdev_io_opt(bd);
1134}
1135
1136static struct exec_cmd_ops iblock_exec_cmd_ops = {
1137 .execute_rw = iblock_execute_rw,
1138 .execute_sync_cache = iblock_execute_sync_cache,
1139 .execute_write_same = iblock_execute_write_same,
1140 .execute_unmap = iblock_execute_unmap,
1141 .execute_pr_out = iblock_execute_pr_out,
1142 .execute_pr_in = iblock_execute_pr_in,
1143};
1144
1145static sense_reason_t
1146iblock_parse_cdb(struct se_cmd *cmd)
1147{
1148 return sbc_parse_cdb(cmd, &iblock_exec_cmd_ops);
1149}
1150
1151static bool iblock_get_write_cache(struct se_device *dev)
1152{
1153 return bdev_write_cache(IBLOCK_DEV(dev)->ibd_bd);
1154}
1155
1156static const struct target_backend_ops iblock_ops = {
1157 .name = "iblock",
1158 .inquiry_prod = "IBLOCK",
1159 .transport_flags_changeable = TRANSPORT_FLAG_PASSTHROUGH_PGR,
1160 .inquiry_rev = IBLOCK_VERSION,
1161 .owner = THIS_MODULE,
1162 .attach_hba = iblock_attach_hba,
1163 .detach_hba = iblock_detach_hba,
1164 .alloc_device = iblock_alloc_device,
1165 .configure_device = iblock_configure_device,
1166 .destroy_device = iblock_destroy_device,
1167 .free_device = iblock_free_device,
1168 .configure_unmap = iblock_configure_unmap,
1169 .plug_device = iblock_plug_device,
1170 .unplug_device = iblock_unplug_device,
1171 .parse_cdb = iblock_parse_cdb,
1172 .set_configfs_dev_params = iblock_set_configfs_dev_params,
1173 .show_configfs_dev_params = iblock_show_configfs_dev_params,
1174 .get_device_type = sbc_get_device_type,
1175 .get_blocks = iblock_get_blocks,
1176 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas,
1177 .get_lbppbe = iblock_get_lbppbe,
1178 .get_io_min = iblock_get_io_min,
1179 .get_io_opt = iblock_get_io_opt,
1180 .get_write_cache = iblock_get_write_cache,
1181 .tb_dev_attrib_attrs = sbc_attrib_attrs,
1182};
1183
1184static int __init iblock_module_init(void)
1185{
1186 return transport_backend_register(&iblock_ops);
1187}
1188
1189static void __exit iblock_module_exit(void)
1190{
1191 target_backend_unregister(&iblock_ops);
1192}
1193
1194MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
1195MODULE_AUTHOR("nab@Linux-iSCSI.org");
1196MODULE_LICENSE("GPL");
1197
1198module_init(iblock_module_init);
1199module_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 * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
8 * Copyright (c) 2005, 2006, 2007 SBE, Inc.
9 * Copyright (c) 2007-2010 Rising Tide Systems
10 * Copyright (c) 2008-2010 Linux-iSCSI.org
11 *
12 * Nicholas A. Bellinger <nab@kernel.org>
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 *
28 ******************************************************************************/
29
30#include <linux/version.h>
31#include <linux/string.h>
32#include <linux/parser.h>
33#include <linux/timer.h>
34#include <linux/fs.h>
35#include <linux/blkdev.h>
36#include <linux/slab.h>
37#include <linux/spinlock.h>
38#include <linux/bio.h>
39#include <linux/genhd.h>
40#include <linux/file.h>
41#include <scsi/scsi.h>
42#include <scsi/scsi_host.h>
43
44#include <target/target_core_base.h>
45#include <target/target_core_device.h>
46#include <target/target_core_transport.h>
47
48#include "target_core_iblock.h"
49
50static struct se_subsystem_api iblock_template;
51
52static void iblock_bio_done(struct bio *, int);
53
54/* iblock_attach_hba(): (Part of se_subsystem_api_t template)
55 *
56 *
57 */
58static int iblock_attach_hba(struct se_hba *hba, u32 host_id)
59{
60 struct iblock_hba *ib_host;
61
62 ib_host = kzalloc(sizeof(struct iblock_hba), GFP_KERNEL);
63 if (!ib_host) {
64 pr_err("Unable to allocate memory for"
65 " struct iblock_hba\n");
66 return -ENOMEM;
67 }
68
69 ib_host->iblock_host_id = host_id;
70
71 hba->hba_ptr = ib_host;
72
73 pr_debug("CORE_HBA[%d] - TCM iBlock HBA Driver %s on"
74 " Generic Target Core Stack %s\n", hba->hba_id,
75 IBLOCK_VERSION, TARGET_CORE_MOD_VERSION);
76
77 pr_debug("CORE_HBA[%d] - Attached iBlock HBA: %u to Generic\n",
78 hba->hba_id, ib_host->iblock_host_id);
79
80 return 0;
81}
82
83static void iblock_detach_hba(struct se_hba *hba)
84{
85 struct iblock_hba *ib_host = hba->hba_ptr;
86
87 pr_debug("CORE_HBA[%d] - Detached iBlock HBA: %u from Generic"
88 " Target Core\n", hba->hba_id, ib_host->iblock_host_id);
89
90 kfree(ib_host);
91 hba->hba_ptr = NULL;
92}
93
94static void *iblock_allocate_virtdevice(struct se_hba *hba, const char *name)
95{
96 struct iblock_dev *ib_dev = NULL;
97 struct iblock_hba *ib_host = hba->hba_ptr;
98
99 ib_dev = kzalloc(sizeof(struct iblock_dev), GFP_KERNEL);
100 if (!ib_dev) {
101 pr_err("Unable to allocate struct iblock_dev\n");
102 return NULL;
103 }
104 ib_dev->ibd_host = ib_host;
105
106 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
107
108 return ib_dev;
109}
110
111static struct se_device *iblock_create_virtdevice(
112 struct se_hba *hba,
113 struct se_subsystem_dev *se_dev,
114 void *p)
115{
116 struct iblock_dev *ib_dev = p;
117 struct se_device *dev;
118 struct se_dev_limits dev_limits;
119 struct block_device *bd = NULL;
120 struct request_queue *q;
121 struct queue_limits *limits;
122 u32 dev_flags = 0;
123 int ret = -EINVAL;
124
125 if (!ib_dev) {
126 pr_err("Unable to locate struct iblock_dev parameter\n");
127 return ERR_PTR(ret);
128 }
129 memset(&dev_limits, 0, sizeof(struct se_dev_limits));
130 /*
131 * These settings need to be made tunable..
132 */
133 ib_dev->ibd_bio_set = bioset_create(32, 64);
134 if (!ib_dev->ibd_bio_set) {
135 pr_err("IBLOCK: Unable to create bioset()\n");
136 return ERR_PTR(-ENOMEM);
137 }
138 pr_debug("IBLOCK: Created bio_set()\n");
139 /*
140 * iblock_check_configfs_dev_params() ensures that ib_dev->ibd_udev_path
141 * must already have been set in order for echo 1 > $HBA/$DEV/enable to run.
142 */
143 pr_debug( "IBLOCK: Claiming struct block_device: %s\n",
144 ib_dev->ibd_udev_path);
145
146 bd = blkdev_get_by_path(ib_dev->ibd_udev_path,
147 FMODE_WRITE|FMODE_READ|FMODE_EXCL, ib_dev);
148 if (IS_ERR(bd)) {
149 ret = PTR_ERR(bd);
150 goto failed;
151 }
152 /*
153 * Setup the local scope queue_limits from struct request_queue->limits
154 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
155 */
156 q = bdev_get_queue(bd);
157 limits = &dev_limits.limits;
158 limits->logical_block_size = bdev_logical_block_size(bd);
159 limits->max_hw_sectors = queue_max_hw_sectors(q);
160 limits->max_sectors = queue_max_sectors(q);
161 dev_limits.hw_queue_depth = q->nr_requests;
162 dev_limits.queue_depth = q->nr_requests;
163
164 ib_dev->ibd_bd = bd;
165
166 dev = transport_add_device_to_core_hba(hba,
167 &iblock_template, se_dev, dev_flags, ib_dev,
168 &dev_limits, "IBLOCK", IBLOCK_VERSION);
169 if (!dev)
170 goto failed;
171
172 /*
173 * Check if the underlying struct block_device request_queue supports
174 * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
175 * in ATA and we need to set TPE=1
176 */
177 if (blk_queue_discard(q)) {
178 dev->se_sub_dev->se_dev_attrib.max_unmap_lba_count =
179 q->limits.max_discard_sectors;
180 /*
181 * Currently hardcoded to 1 in Linux/SCSI code..
182 */
183 dev->se_sub_dev->se_dev_attrib.max_unmap_block_desc_count = 1;
184 dev->se_sub_dev->se_dev_attrib.unmap_granularity =
185 q->limits.discard_granularity;
186 dev->se_sub_dev->se_dev_attrib.unmap_granularity_alignment =
187 q->limits.discard_alignment;
188
189 pr_debug("IBLOCK: BLOCK Discard support available,"
190 " disabled by default\n");
191 }
192
193 if (blk_queue_nonrot(q))
194 dev->se_sub_dev->se_dev_attrib.is_nonrot = 1;
195
196 return dev;
197
198failed:
199 if (ib_dev->ibd_bio_set) {
200 bioset_free(ib_dev->ibd_bio_set);
201 ib_dev->ibd_bio_set = NULL;
202 }
203 ib_dev->ibd_bd = NULL;
204 return ERR_PTR(ret);
205}
206
207static void iblock_free_device(void *p)
208{
209 struct iblock_dev *ib_dev = p;
210
211 if (ib_dev->ibd_bd != NULL)
212 blkdev_put(ib_dev->ibd_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
213 if (ib_dev->ibd_bio_set != NULL)
214 bioset_free(ib_dev->ibd_bio_set);
215 kfree(ib_dev);
216}
217
218static inline struct iblock_req *IBLOCK_REQ(struct se_task *task)
219{
220 return container_of(task, struct iblock_req, ib_task);
221}
222
223static struct se_task *
224iblock_alloc_task(unsigned char *cdb)
225{
226 struct iblock_req *ib_req;
227
228 ib_req = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
229 if (!ib_req) {
230 pr_err("Unable to allocate memory for struct iblock_req\n");
231 return NULL;
232 }
233
234 atomic_set(&ib_req->ib_bio_cnt, 0);
235 return &ib_req->ib_task;
236}
237
238static unsigned long long iblock_emulate_read_cap_with_block_size(
239 struct se_device *dev,
240 struct block_device *bd,
241 struct request_queue *q)
242{
243 unsigned long long blocks_long = (div_u64(i_size_read(bd->bd_inode),
244 bdev_logical_block_size(bd)) - 1);
245 u32 block_size = bdev_logical_block_size(bd);
246
247 if (block_size == dev->se_sub_dev->se_dev_attrib.block_size)
248 return blocks_long;
249
250 switch (block_size) {
251 case 4096:
252 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
253 case 2048:
254 blocks_long <<= 1;
255 break;
256 case 1024:
257 blocks_long <<= 2;
258 break;
259 case 512:
260 blocks_long <<= 3;
261 default:
262 break;
263 }
264 break;
265 case 2048:
266 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
267 case 4096:
268 blocks_long >>= 1;
269 break;
270 case 1024:
271 blocks_long <<= 1;
272 break;
273 case 512:
274 blocks_long <<= 2;
275 break;
276 default:
277 break;
278 }
279 break;
280 case 1024:
281 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
282 case 4096:
283 blocks_long >>= 2;
284 break;
285 case 2048:
286 blocks_long >>= 1;
287 break;
288 case 512:
289 blocks_long <<= 1;
290 break;
291 default:
292 break;
293 }
294 break;
295 case 512:
296 switch (dev->se_sub_dev->se_dev_attrib.block_size) {
297 case 4096:
298 blocks_long >>= 3;
299 break;
300 case 2048:
301 blocks_long >>= 2;
302 break;
303 case 1024:
304 blocks_long >>= 1;
305 break;
306 default:
307 break;
308 }
309 break;
310 default:
311 break;
312 }
313
314 return blocks_long;
315}
316
317/*
318 * Emulate SYCHRONIZE_CACHE_*
319 */
320static void iblock_emulate_sync_cache(struct se_task *task)
321{
322 struct se_cmd *cmd = task->task_se_cmd;
323 struct iblock_dev *ib_dev = cmd->se_dev->dev_ptr;
324 int immed = (cmd->t_task_cdb[1] & 0x2);
325 sector_t error_sector;
326 int ret;
327
328 /*
329 * If the Immediate bit is set, queue up the GOOD response
330 * for this SYNCHRONIZE_CACHE op
331 */
332 if (immed)
333 transport_complete_sync_cache(cmd, 1);
334
335 /*
336 * blkdev_issue_flush() does not support a specifying a range, so
337 * we have to flush the entire cache.
338 */
339 ret = blkdev_issue_flush(ib_dev->ibd_bd, GFP_KERNEL, &error_sector);
340 if (ret != 0) {
341 pr_err("IBLOCK: block_issue_flush() failed: %d "
342 " error_sector: %llu\n", ret,
343 (unsigned long long)error_sector);
344 }
345
346 if (!immed)
347 transport_complete_sync_cache(cmd, ret == 0);
348}
349
350/*
351 * Tell TCM Core that we are capable of WriteCache emulation for
352 * an underlying struct se_device.
353 */
354static int iblock_emulated_write_cache(struct se_device *dev)
355{
356 return 1;
357}
358
359static int iblock_emulated_dpo(struct se_device *dev)
360{
361 return 0;
362}
363
364/*
365 * Tell TCM Core that we will be emulating Forced Unit Access (FUA) for WRITEs
366 * for TYPE_DISK.
367 */
368static int iblock_emulated_fua_write(struct se_device *dev)
369{
370 return 1;
371}
372
373static int iblock_emulated_fua_read(struct se_device *dev)
374{
375 return 0;
376}
377
378static int iblock_do_task(struct se_task *task)
379{
380 struct se_device *dev = task->task_se_cmd->se_dev;
381 struct iblock_req *req = IBLOCK_REQ(task);
382 struct bio *bio = req->ib_bio, *nbio = NULL;
383 struct blk_plug plug;
384 int rw;
385
386 if (task->task_data_direction == DMA_TO_DEVICE) {
387 /*
388 * Force data to disk if we pretend to not have a volatile
389 * write cache, or the initiator set the Force Unit Access bit.
390 */
391 if (dev->se_sub_dev->se_dev_attrib.emulate_write_cache == 0 ||
392 (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0 &&
393 task->task_se_cmd->t_tasks_fua))
394 rw = WRITE_FUA;
395 else
396 rw = WRITE;
397 } else {
398 rw = READ;
399 }
400
401 blk_start_plug(&plug);
402 while (bio) {
403 nbio = bio->bi_next;
404 bio->bi_next = NULL;
405 pr_debug("Calling submit_bio() task: %p bio: %p"
406 " bio->bi_sector: %llu\n", task, bio,
407 (unsigned long long)bio->bi_sector);
408
409 submit_bio(rw, bio);
410 bio = nbio;
411 }
412 blk_finish_plug(&plug);
413
414 return PYX_TRANSPORT_SENT_TO_TRANSPORT;
415}
416
417static int iblock_do_discard(struct se_device *dev, sector_t lba, u32 range)
418{
419 struct iblock_dev *ibd = dev->dev_ptr;
420 struct block_device *bd = ibd->ibd_bd;
421 int barrier = 0;
422
423 return blkdev_issue_discard(bd, lba, range, GFP_KERNEL, barrier);
424}
425
426static void iblock_free_task(struct se_task *task)
427{
428 struct iblock_req *req = IBLOCK_REQ(task);
429 struct bio *bio, *hbio = req->ib_bio;
430 /*
431 * We only release the bio(s) here if iblock_bio_done() has not called
432 * bio_put() -> iblock_bio_destructor().
433 */
434 while (hbio != NULL) {
435 bio = hbio;
436 hbio = hbio->bi_next;
437 bio->bi_next = NULL;
438 bio_put(bio);
439 }
440
441 kfree(req);
442}
443
444enum {
445 Opt_udev_path, Opt_force, Opt_err
446};
447
448static match_table_t tokens = {
449 {Opt_udev_path, "udev_path=%s"},
450 {Opt_force, "force=%d"},
451 {Opt_err, NULL}
452};
453
454static ssize_t iblock_set_configfs_dev_params(struct se_hba *hba,
455 struct se_subsystem_dev *se_dev,
456 const char *page, ssize_t count)
457{
458 struct iblock_dev *ib_dev = se_dev->se_dev_su_ptr;
459 char *orig, *ptr, *arg_p, *opts;
460 substring_t args[MAX_OPT_ARGS];
461 int ret = 0, token;
462
463 opts = kstrdup(page, GFP_KERNEL);
464 if (!opts)
465 return -ENOMEM;
466
467 orig = opts;
468
469 while ((ptr = strsep(&opts, ",")) != NULL) {
470 if (!*ptr)
471 continue;
472
473 token = match_token(ptr, tokens, args);
474 switch (token) {
475 case Opt_udev_path:
476 if (ib_dev->ibd_bd) {
477 pr_err("Unable to set udev_path= while"
478 " ib_dev->ibd_bd exists\n");
479 ret = -EEXIST;
480 goto out;
481 }
482 arg_p = match_strdup(&args[0]);
483 if (!arg_p) {
484 ret = -ENOMEM;
485 break;
486 }
487 snprintf(ib_dev->ibd_udev_path, SE_UDEV_PATH_LEN,
488 "%s", arg_p);
489 kfree(arg_p);
490 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
491 ib_dev->ibd_udev_path);
492 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
493 break;
494 case Opt_force:
495 break;
496 default:
497 break;
498 }
499 }
500
501out:
502 kfree(orig);
503 return (!ret) ? count : ret;
504}
505
506static ssize_t iblock_check_configfs_dev_params(
507 struct se_hba *hba,
508 struct se_subsystem_dev *se_dev)
509{
510 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
511
512 if (!(ibd->ibd_flags & IBDF_HAS_UDEV_PATH)) {
513 pr_err("Missing udev_path= parameters for IBLOCK\n");
514 return -EINVAL;
515 }
516
517 return 0;
518}
519
520static ssize_t iblock_show_configfs_dev_params(
521 struct se_hba *hba,
522 struct se_subsystem_dev *se_dev,
523 char *b)
524{
525 struct iblock_dev *ibd = se_dev->se_dev_su_ptr;
526 struct block_device *bd = ibd->ibd_bd;
527 char buf[BDEVNAME_SIZE];
528 ssize_t bl = 0;
529
530 if (bd)
531 bl += sprintf(b + bl, "iBlock device: %s",
532 bdevname(bd, buf));
533 if (ibd->ibd_flags & IBDF_HAS_UDEV_PATH) {
534 bl += sprintf(b + bl, " UDEV PATH: %s\n",
535 ibd->ibd_udev_path);
536 } else
537 bl += sprintf(b + bl, "\n");
538
539 bl += sprintf(b + bl, " ");
540 if (bd) {
541 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
542 MAJOR(bd->bd_dev), MINOR(bd->bd_dev), (!bd->bd_contains) ?
543 "" : (bd->bd_holder == (struct iblock_dev *)ibd) ?
544 "CLAIMED: IBLOCK" : "CLAIMED: OS");
545 } else {
546 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
547 }
548
549 return bl;
550}
551
552static void iblock_bio_destructor(struct bio *bio)
553{
554 struct se_task *task = bio->bi_private;
555 struct iblock_dev *ib_dev = task->se_dev->dev_ptr;
556
557 bio_free(bio, ib_dev->ibd_bio_set);
558}
559
560static struct bio *iblock_get_bio(
561 struct se_task *task,
562 struct iblock_req *ib_req,
563 struct iblock_dev *ib_dev,
564 int *ret,
565 sector_t lba,
566 u32 sg_num)
567{
568 struct bio *bio;
569
570 bio = bio_alloc_bioset(GFP_NOIO, sg_num, ib_dev->ibd_bio_set);
571 if (!bio) {
572 pr_err("Unable to allocate memory for bio\n");
573 *ret = PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
574 return NULL;
575 }
576
577 pr_debug("Allocated bio: %p task_sg_nents: %u using ibd_bio_set:"
578 " %p\n", bio, task->task_sg_nents, ib_dev->ibd_bio_set);
579 pr_debug("Allocated bio: %p task_size: %u\n", bio, task->task_size);
580
581 bio->bi_bdev = ib_dev->ibd_bd;
582 bio->bi_private = task;
583 bio->bi_destructor = iblock_bio_destructor;
584 bio->bi_end_io = &iblock_bio_done;
585 bio->bi_sector = lba;
586 atomic_inc(&ib_req->ib_bio_cnt);
587
588 pr_debug("Set bio->bi_sector: %llu\n", (unsigned long long)bio->bi_sector);
589 pr_debug("Set ib_req->ib_bio_cnt: %d\n",
590 atomic_read(&ib_req->ib_bio_cnt));
591 return bio;
592}
593
594static int iblock_map_data_SG(struct se_task *task)
595{
596 struct se_cmd *cmd = task->task_se_cmd;
597 struct se_device *dev = cmd->se_dev;
598 struct iblock_dev *ib_dev = task->se_dev->dev_ptr;
599 struct iblock_req *ib_req = IBLOCK_REQ(task);
600 struct bio *bio = NULL, *hbio = NULL, *tbio = NULL;
601 struct scatterlist *sg;
602 int ret = 0;
603 u32 i, sg_num = task->task_sg_nents;
604 sector_t block_lba;
605 /*
606 * Do starting conversion up from non 512-byte blocksize with
607 * struct se_task SCSI blocksize into Linux/Block 512 units for BIO.
608 */
609 if (dev->se_sub_dev->se_dev_attrib.block_size == 4096)
610 block_lba = (task->task_lba << 3);
611 else if (dev->se_sub_dev->se_dev_attrib.block_size == 2048)
612 block_lba = (task->task_lba << 2);
613 else if (dev->se_sub_dev->se_dev_attrib.block_size == 1024)
614 block_lba = (task->task_lba << 1);
615 else if (dev->se_sub_dev->se_dev_attrib.block_size == 512)
616 block_lba = task->task_lba;
617 else {
618 pr_err("Unsupported SCSI -> BLOCK LBA conversion:"
619 " %u\n", dev->se_sub_dev->se_dev_attrib.block_size);
620 return PYX_TRANSPORT_LU_COMM_FAILURE;
621 }
622
623 bio = iblock_get_bio(task, ib_req, ib_dev, &ret, block_lba, sg_num);
624 if (!bio)
625 return ret;
626
627 ib_req->ib_bio = bio;
628 hbio = tbio = bio;
629 /*
630 * Use fs/bio.c:bio_add_pages() to setup the bio_vec maplist
631 * from task->task_sg -> struct scatterlist memory.
632 */
633 for_each_sg(task->task_sg, sg, task->task_sg_nents, i) {
634 pr_debug("task: %p bio: %p Calling bio_add_page(): page:"
635 " %p len: %u offset: %u\n", task, bio, sg_page(sg),
636 sg->length, sg->offset);
637again:
638 ret = bio_add_page(bio, sg_page(sg), sg->length, sg->offset);
639 if (ret != sg->length) {
640
641 pr_debug("*** Set bio->bi_sector: %llu\n",
642 (unsigned long long)bio->bi_sector);
643 pr_debug("** task->task_size: %u\n",
644 task->task_size);
645 pr_debug("*** bio->bi_max_vecs: %u\n",
646 bio->bi_max_vecs);
647 pr_debug("*** bio->bi_vcnt: %u\n",
648 bio->bi_vcnt);
649
650 bio = iblock_get_bio(task, ib_req, ib_dev, &ret,
651 block_lba, sg_num);
652 if (!bio)
653 goto fail;
654
655 tbio = tbio->bi_next = bio;
656 pr_debug("-----------------> Added +1 bio: %p to"
657 " list, Going to again\n", bio);
658 goto again;
659 }
660 /* Always in 512 byte units for Linux/Block */
661 block_lba += sg->length >> IBLOCK_LBA_SHIFT;
662 sg_num--;
663 pr_debug("task: %p bio-add_page() passed!, decremented"
664 " sg_num to %u\n", task, sg_num);
665 pr_debug("task: %p bio_add_page() passed!, increased lba"
666 " to %llu\n", task, (unsigned long long)block_lba);
667 pr_debug("task: %p bio_add_page() passed!, bio->bi_vcnt:"
668 " %u\n", task, bio->bi_vcnt);
669 }
670
671 return 0;
672fail:
673 while (hbio) {
674 bio = hbio;
675 hbio = hbio->bi_next;
676 bio->bi_next = NULL;
677 bio_put(bio);
678 }
679 return ret;
680}
681
682static unsigned char *iblock_get_cdb(struct se_task *task)
683{
684 return IBLOCK_REQ(task)->ib_scsi_cdb;
685}
686
687static u32 iblock_get_device_rev(struct se_device *dev)
688{
689 return SCSI_SPC_2; /* Returns SPC-3 in Initiator Data */
690}
691
692static u32 iblock_get_device_type(struct se_device *dev)
693{
694 return TYPE_DISK;
695}
696
697static sector_t iblock_get_blocks(struct se_device *dev)
698{
699 struct iblock_dev *ibd = dev->dev_ptr;
700 struct block_device *bd = ibd->ibd_bd;
701 struct request_queue *q = bdev_get_queue(bd);
702
703 return iblock_emulate_read_cap_with_block_size(dev, bd, q);
704}
705
706static void iblock_bio_done(struct bio *bio, int err)
707{
708 struct se_task *task = bio->bi_private;
709 struct iblock_req *ibr = IBLOCK_REQ(task);
710 /*
711 * Set -EIO if !BIO_UPTODATE and the passed is still err=0
712 */
713 if (!test_bit(BIO_UPTODATE, &bio->bi_flags) && !err)
714 err = -EIO;
715
716 if (err != 0) {
717 pr_err("test_bit(BIO_UPTODATE) failed for bio: %p,"
718 " err: %d\n", bio, err);
719 /*
720 * Bump the ib_bio_err_cnt and release bio.
721 */
722 atomic_inc(&ibr->ib_bio_err_cnt);
723 smp_mb__after_atomic_inc();
724 bio_put(bio);
725 /*
726 * Wait to complete the task until the last bio as completed.
727 */
728 if (!atomic_dec_and_test(&ibr->ib_bio_cnt))
729 return;
730
731 ibr->ib_bio = NULL;
732 transport_complete_task(task, 0);
733 return;
734 }
735 pr_debug("done[%p] bio: %p task_lba: %llu bio_lba: %llu err=%d\n",
736 task, bio, task->task_lba, (unsigned long long)bio->bi_sector, err);
737 /*
738 * bio_put() will call iblock_bio_destructor() to release the bio back
739 * to ibr->ib_bio_set.
740 */
741 bio_put(bio);
742 /*
743 * Wait to complete the task until the last bio as completed.
744 */
745 if (!atomic_dec_and_test(&ibr->ib_bio_cnt))
746 return;
747 /*
748 * Return GOOD status for task if zero ib_bio_err_cnt exists.
749 */
750 ibr->ib_bio = NULL;
751 transport_complete_task(task, (!atomic_read(&ibr->ib_bio_err_cnt)));
752}
753
754static struct se_subsystem_api iblock_template = {
755 .name = "iblock",
756 .owner = THIS_MODULE,
757 .transport_type = TRANSPORT_PLUGIN_VHBA_PDEV,
758 .map_data_SG = iblock_map_data_SG,
759 .attach_hba = iblock_attach_hba,
760 .detach_hba = iblock_detach_hba,
761 .allocate_virtdevice = iblock_allocate_virtdevice,
762 .create_virtdevice = iblock_create_virtdevice,
763 .free_device = iblock_free_device,
764 .dpo_emulated = iblock_emulated_dpo,
765 .fua_write_emulated = iblock_emulated_fua_write,
766 .fua_read_emulated = iblock_emulated_fua_read,
767 .write_cache_emulated = iblock_emulated_write_cache,
768 .alloc_task = iblock_alloc_task,
769 .do_task = iblock_do_task,
770 .do_discard = iblock_do_discard,
771 .do_sync_cache = iblock_emulate_sync_cache,
772 .free_task = iblock_free_task,
773 .check_configfs_dev_params = iblock_check_configfs_dev_params,
774 .set_configfs_dev_params = iblock_set_configfs_dev_params,
775 .show_configfs_dev_params = iblock_show_configfs_dev_params,
776 .get_cdb = iblock_get_cdb,
777 .get_device_rev = iblock_get_device_rev,
778 .get_device_type = iblock_get_device_type,
779 .get_blocks = iblock_get_blocks,
780};
781
782static int __init iblock_module_init(void)
783{
784 return transport_subsystem_register(&iblock_template);
785}
786
787static void iblock_module_exit(void)
788{
789 transport_subsystem_release(&iblock_template);
790}
791
792MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
793MODULE_AUTHOR("nab@Linux-iSCSI.org");
794MODULE_LICENSE("GPL");
795
796module_init(iblock_module_init);
797module_exit(iblock_module_exit);