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(size: 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(n: nr_cpu_ids, size: 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(objp: 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(attrib: &dev->dev_attrib,
87 bdev: 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, flags: 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(path: ib_dev->ibd_udev_path, mode, holder: ib_dev,
121 NULL);
122 if (IS_ERR(ptr: bdev_handle)) {
123 ret = PTR_ERR(ptr: 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(bdev: bd);
130
131 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bdev: 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(bdev: 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(bdev: bd))
148 dev->dev_attrib.is_nonrot = 1;
149
150 bi = bdev_get_integrity(bdev: 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(handle: 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(objp: ib_dev->ibd_plug);
196 kfree(objp: ib_dev);
197}
198
199static void iblock_free_device(struct se_device *dev)
200{
201 call_rcu(head: &dev->rcu_head, func: 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(handle: 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(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, addr: &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, addr: &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(bdev: ib_dev->ibd_bd);
244 unsigned long long blocks_long =
245 div_u64(dividend: bdev_nr_bytes(bdev: ib_dev->ibd_bd), divisor: 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(r: &ibr->pending))
324 return;
325
326 if (blk_status == BLK_STS_RESV_CONFLICT)
327 status = SAM_STAT_RESERVATION_CONFLICT;
328 else if (atomic_read(v: &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(objp: 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(v: &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(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(bdev: ib_dev->ibd_bd, nr_vecs: bio_max_segs(nr_segs: sg_num), opf,
368 GFP_NOIO, bs: &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(bl: 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(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(bdev: ib_dev->ibd_bd, nr_vecs: 0, opf: 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(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 sector: target_to_linux_sector(dev, lb: lba),
448 nr_sects: target_to_linux_sector(dev, lb: 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(page: 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(p: buf, c: 0x00, size: cmd->data_length);
474 kunmap(page: sg_page(sg));
475
476 if (not_zero)
477 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
478
479 ret = blkdev_issue_zeroout(bdev,
480 sector: target_to_linux_sector(dev, lb: cmd->t_task_lba),
481 nr_sects: target_to_linux_sector(dev,
482 lb: 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(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, lb: cmd->t_task_lba);
501 sector_t sectors = target_to_linux_sector(dev,
502 lb: 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(size: sizeof(struct iblock_req), GFP_KERNEL);
529 if (!ibr)
530 goto fail;
531 cmd->priv = ibr;
532
533 bio = iblock_get_bio(cmd, lba: block_lba, sg_num: 1, opf: REQ_OP_WRITE);
534 if (!bio)
535 goto fail_free_ibr;
536
537 bio_list_init(bl: &list);
538 bio_list_add(bl: &list, bio);
539
540 refcount_set(r: &ibr->pending, n: 1);
541
542 while (sectors) {
543 while (bio_add_page(bio, page: sg_page(sg), len: sg->length, off: sg->offset)
544 != sg->length) {
545
546 bio = iblock_get_bio(cmd, lba: block_lba, sg_num: 1, opf: REQ_OP_WRITE);
547 if (!bio)
548 goto fail_put_bios;
549
550 refcount_inc(r: &ibr->pending);
551 bio_list_add(bl: &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: &list);
560 return 0;
561
562fail_put_bios:
563 while ((bio = bio_list_pop(bl: &list)))
564 bio_put(bio);
565fail_free_ibr:
566 kfree(objp: 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(s: 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, table: 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(s: arg_p, base: 0, res: &tmp_readonly);
626 kfree(objp: 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(objp: 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(buf: b + bl, fmt: "iBlock device: %pg", bd);
655 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
656 bl += sprintf(buf: b + bl, fmt: " UDEV PATH: %s",
657 ib_dev->ibd_udev_path);
658 bl += sprintf(buf: b + bl, fmt: " readonly: %d\n", ib_dev->ibd_readonly);
659
660 bl += sprintf(buf: b + bl, fmt: " ");
661 if (bd) {
662 bl += sprintf(buf: b + bl, fmt: "Major: %d Minor: %d %s\n",
663 MAJOR(bd->bd_dev), MINOR(bd->bd_dev),
664 "CLAIMED: IBLOCK");
665 } else {
666 bl += sprintf(buf: b + bl, fmt: "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(bdev: 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(nr_segs: cmd->t_prot_nents));
690 if (IS_ERR(ptr: bip)) {
691 pr_err("Unable to allocate bio_integrity_payload\n");
692 return PTR_ERR(ptr: bip);
693 }
694
695 /* virtual start sector must be in integrity interval units */
696 bip_set_seed(bip, seed: 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, lb: 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(bdev: ib_dev->ibd_bd)) {
757 if (cmd->se_cmd_flags & SCF_FUA)
758 opf |= REQ_FUA;
759 else if (!bdev_write_cache(bdev: 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(size: sizeof(struct iblock_req), GFP_KERNEL);
768 if (!ibr)
769 goto fail;
770 cmd->priv = ibr;
771
772 if (!sgl_nents) {
773 refcount_set(r: &ibr->pending, n: 1);
774 iblock_complete_cmd(cmd, BLK_STS_OK);
775 return 0;
776 }
777
778 bio = iblock_get_bio(cmd, lba: block_lba, sg_num: sgl_nents, opf);
779 if (!bio)
780 goto fail_free_ibr;
781
782 bio_list_init(bl: &list);
783 bio_list_add(bl: &list, bio);
784
785 refcount_set(r: &ibr->pending, n: 2);
786 bio_cnt = 1;
787
788 if (cmd->prot_type && dev->dev_attrib.pi_prot_type)
789 sg_miter_start(miter: &prot_miter, sgl: cmd->t_prot_sg, nents: cmd->t_prot_nents,
790 flags: 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, page: sg_page(sg), len: sg->length, off: sg->offset)
799 != sg->length) {
800 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
801 rc = iblock_alloc_bip(cmd, bio, miter: &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: &list);
808 bio_cnt = 0;
809 }
810
811 bio = iblock_get_bio(cmd, lba: block_lba, sg_num, opf);
812 if (!bio)
813 goto fail_put_bios;
814
815 refcount_inc(r: &ibr->pending);
816 bio_list_add(bl: &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, miter: &prot_miter);
827 if (rc)
828 goto fail_put_bios;
829 }
830
831 iblock_submit_bios(list: &list);
832 iblock_complete_cmd(cmd, BLK_STS_OK);
833 return 0;
834
835fail_put_bios:
836 while ((bio = bio_list_pop(bl: &list)))
837 bio_put(bio);
838fail_free_ibr:
839 kfree(objp: 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(val: len, p: &param_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(size: 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(objp: 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(val: keys->generation, p: &param_data[0]);
1011 if (!keys->num_keys) {
1012 put_unaligned_be32(val: 0, p: &param_data[4]);
1013 goto free_keys;
1014 }
1015
1016 put_unaligned_be32(val: 8 * keys->num_keys, p: &param_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(val: keys->keys[i], p: &param_data[data_offset]);
1024 data_offset += 8;
1025 }
1026
1027free_keys:
1028 kfree(objp: 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(val: rsv.generation, p: &param_data[0]);
1055 if (!block_pr_type_to_scsi(type: rsv.type)) {
1056 put_unaligned_be32(val: 0, p: &param_data[4]);
1057 return TCM_NO_SENSE;
1058 }
1059
1060 put_unaligned_be32(val: 16, p: &param_data[4]);
1061
1062 if (cmd->data_length < 16)
1063 return TCM_NO_SENSE;
1064 put_unaligned_be64(val: rsv.key, p: &param_data[8]);
1065
1066 if (cmd->data_length < 22)
1067 return TCM_NO_SENSE;
1068 param_data[21] = block_pr_type_to_scsi(type: 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(bdev: bd);
1103 if (ret == -1)
1104 return 0;
1105
1106 /* convert offset-bytes to offset-lbas */
1107 return ret / bdev_logical_block_size(bdev: 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(bdev: bd) / bdev_logical_block_size(bdev: 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(bdev: 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(bdev: 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, ops: &iblock_exec_cmd_ops);
1149}
1150
1151static bool iblock_get_write_cache(struct se_device *dev)
1152{
1153 return bdev_write_cache(bdev: 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);
1200

source code of linux/drivers/target/target_core_iblock.c