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
IBLOCK_DEV(struct se_device * dev)40 static inline struct iblock_dev *IBLOCK_DEV(struct se_device *dev)
41 {
42 return container_of(dev, struct iblock_dev, dev);
43 }
44
45
iblock_attach_hba(struct se_hba * hba,u32 host_id)46 static 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
iblock_detach_hba(struct se_hba * hba)54 static void iblock_detach_hba(struct se_hba *hba)
55 {
56 }
57
iblock_alloc_device(struct se_hba * hba,const char * name)58 static 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
77 free_dev:
78 kfree(ib_dev);
79 return NULL;
80 }
81
iblock_configure_unmap(struct se_device * dev)82 static 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
iblock_configure_device(struct se_device * dev)90 static 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
185 out_blkdev_put:
186 fput(ib_dev->ibd_bdev_file);
187 out_free_bioset:
188 bioset_exit(&ib_dev->ibd_bio_set);
189 out:
190 return ret;
191 }
192
iblock_dev_call_rcu(struct rcu_head * p)193 static 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
iblock_free_device(struct se_device * dev)202 static void iblock_free_device(struct se_device *dev)
203 {
204 call_rcu(&dev->rcu_head, iblock_dev_call_rcu);
205 }
206
iblock_destroy_device(struct se_device * dev)207 static 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
iblock_plug_device(struct se_device * se_dev)216 static 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
iblock_unplug_device(struct se_dev_plug * se_plug)234 static 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
iblock_get_blocks(struct se_device * dev)243 static 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
iblock_complete_cmd(struct se_cmd * cmd,blk_status_t blk_status)321 static 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
iblock_bio_done(struct bio * bio)340 static 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
iblock_get_bio(struct se_cmd * cmd,sector_t lba,u32 sg_num,blk_opf_t opf)360 static 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
iblock_submit_bios(struct bio_list * list)384 static 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
iblock_end_io_flush(struct bio * bio)398 static 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 */
419 static sense_reason_t
iblock_execute_sync_cache(struct se_cmd * cmd)420 iblock_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
442 static sense_reason_t
iblock_execute_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)443 iblock_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
461 static sense_reason_t
iblock_execute_zero_out(struct block_device * bdev,struct se_cmd * cmd)462 iblock_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
494 static sense_reason_t
iblock_execute_write_same(struct se_cmd * cmd)495 iblock_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
565 fail_put_bios:
566 while ((bio = bio_list_pop(&list)))
567 bio_put(bio);
568 fail_free_ibr:
569 kfree(ibr);
570 fail:
571 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
572 }
573
574 enum {
575 Opt_udev_path, Opt_readonly, Opt_force, Opt_err
576 };
577
578 static 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
iblock_set_configfs_dev_params(struct se_device * dev,const char * page,ssize_t count)585 static 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
645 out:
646 kfree(orig);
647 return (!ret) ? count : ret;
648 }
649
iblock_show_configfs_dev_params(struct se_device * dev,char * b)650 static 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
675 static int
iblock_alloc_bip(struct se_cmd * cmd,struct bio * bio,struct sg_mapping_iter * miter)676 iblock_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
729 static sense_reason_t
iblock_execute_rw(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)730 iblock_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
838 fail_put_bios:
839 while ((bio = bio_list_pop(&list)))
840 bio_put(bio);
841 fail_free_ibr:
842 kfree(ibr);
843 fail:
844 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
845 }
846
iblock_execute_pr_out(struct se_cmd * cmd,u8 sa,u64 key,u64 sa_key,u8 type,bool aptpl)847 static 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
iblock_pr_report_caps(unsigned char * param_data)924 static 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
iblock_pr_read_keys(struct se_cmd * cmd,unsigned char * param_data)966 static 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;
993 retry:
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
1030 free_keys:
1031 kfree(keys);
1032 return ret;
1033 }
1034
iblock_pr_read_reservation(struct se_cmd * cmd,unsigned char * param_data)1035 static 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
iblock_execute_pr_in(struct se_cmd * cmd,u8 sa,unsigned char * param_data)1076 static 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
iblock_get_alignment_offset_lbas(struct se_device * dev)1099 static 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
iblock_get_lbppbe(struct se_device * dev)1113 static 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
iblock_get_io_min(struct se_device * dev)1123 static 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
iblock_get_io_opt(struct se_device * dev)1131 static 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
1139 static 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
1148 static sense_reason_t
iblock_parse_cdb(struct se_cmd * cmd)1149 iblock_parse_cdb(struct se_cmd *cmd)
1150 {
1151 return sbc_parse_cdb(cmd, &iblock_exec_cmd_ops);
1152 }
1153
iblock_get_write_cache(struct se_device * dev)1154 static bool iblock_get_write_cache(struct se_device *dev)
1155 {
1156 return bdev_write_cache(IBLOCK_DEV(dev)->ibd_bd);
1157 }
1158
1159 static 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
iblock_module_init(void)1187 static int __init iblock_module_init(void)
1188 {
1189 return transport_backend_register(&iblock_ops);
1190 }
1191
iblock_module_exit(void)1192 static void __exit iblock_module_exit(void)
1193 {
1194 target_backend_unregister(&iblock_ops);
1195 }
1196
1197 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
1198 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1199 MODULE_LICENSE("GPL");
1200
1201 module_init(iblock_module_init);
1202 module_exit(iblock_module_exit);
1203