1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3 * Filename: target_core_iblock.c
4 *
5 * This file contains the Storage Engine <-> Linux BlockIO transport
6 * specific functions.
7 *
8 * (c) Copyright 2003-2013 Datera, Inc.
9 *
10 * Nicholas A. Bellinger <nab@kernel.org>
11 *
12 ******************************************************************************/
13
14 #include <linux/string.h>
15 #include <linux/parser.h>
16 #include <linux/timer.h>
17 #include <linux/fs.h>
18 #include <linux/blkdev.h>
19 #include <linux/blk-integrity.h>
20 #include <linux/slab.h>
21 #include <linux/spinlock.h>
22 #include <linux/bio.h>
23 #include <linux/file.h>
24 #include <linux/module.h>
25 #include <linux/scatterlist.h>
26 #include <linux/pr.h>
27 #include <scsi/scsi_proto.h>
28 #include <scsi/scsi_common.h>
29 #include <linux/unaligned.h>
30
31 #include <target/target_core_base.h>
32 #include <target/target_core_backend.h>
33
34 #include "target_core_iblock.h"
35 #include "target_core_pr.h"
36
37 #define IBLOCK_MAX_BIO_PER_TASK 32 /* max # of bios to submit at a time */
38 #define IBLOCK_BIO_POOL_SIZE 128
39
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 ib_dev->ibd_exclusive = true;
68
69 ib_dev->ibd_plug = kcalloc(nr_cpu_ids, sizeof(*ib_dev->ibd_plug),
70 GFP_KERNEL);
71 if (!ib_dev->ibd_plug)
72 goto free_dev;
73
74 pr_debug( "IBLOCK: Allocated ib_dev for %s\n", name);
75
76 return &ib_dev->dev;
77
78 free_dev:
79 kfree(ib_dev);
80 return NULL;
81 }
82
iblock_configure_unmap(struct se_device * dev)83 static bool iblock_configure_unmap(struct se_device *dev)
84 {
85 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
86
87 return target_configure_unmap_from_queue(&dev->dev_attrib,
88 ib_dev->ibd_bd);
89 }
90
iblock_configure_device(struct se_device * dev)91 static int iblock_configure_device(struct se_device *dev)
92 {
93 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
94 struct request_queue *q;
95 struct file *bdev_file;
96 struct block_device *bd;
97 struct blk_integrity *bi;
98 blk_mode_t mode = BLK_OPEN_READ;
99 void *holder = ib_dev;
100 unsigned int max_write_zeroes_sectors;
101 int ret;
102
103 if (!(ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)) {
104 pr_err("Missing udev_path= parameters for IBLOCK\n");
105 return -EINVAL;
106 }
107
108 ret = bioset_init(&ib_dev->ibd_bio_set, IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
109 if (ret) {
110 pr_err("IBLOCK: Unable to create bioset\n");
111 goto out;
112 }
113
114 pr_debug("IBLOCK: Claiming struct block_device: %s: %d\n",
115 ib_dev->ibd_udev_path, ib_dev->ibd_exclusive);
116
117 if (!ib_dev->ibd_readonly)
118 mode |= BLK_OPEN_WRITE;
119 else
120 dev->dev_flags |= DF_READ_ONLY;
121
122 if (!ib_dev->ibd_exclusive)
123 holder = NULL;
124
125 bdev_file = bdev_file_open_by_path(ib_dev->ibd_udev_path, mode, holder,
126 NULL);
127 if (IS_ERR(bdev_file)) {
128 ret = PTR_ERR(bdev_file);
129 goto out_free_bioset;
130 }
131 ib_dev->ibd_bdev_file = bdev_file;
132 ib_dev->ibd_bd = bd = file_bdev(bdev_file);
133
134 q = bdev_get_queue(bd);
135
136 dev->dev_attrib.hw_block_size = bdev_logical_block_size(bd);
137 dev->dev_attrib.hw_max_sectors = mult_frac(queue_max_hw_sectors(q),
138 SECTOR_SIZE,
139 dev->dev_attrib.hw_block_size);
140 dev->dev_attrib.hw_queue_depth = q->nr_requests;
141
142 /*
143 * Enable write same emulation for IBLOCK and use 0xFFFF as
144 * the smaller WRITE_SAME(10) only has a two-byte block count.
145 */
146 max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd);
147 if (max_write_zeroes_sectors)
148 dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors;
149 else
150 dev->dev_attrib.max_write_same_len = 0xFFFF;
151
152 if (bdev_nonrot(bd))
153 dev->dev_attrib.is_nonrot = 1;
154
155 bi = bdev_get_integrity(bd);
156 if (!bi)
157 return 0;
158
159 switch (bi->csum_type) {
160 case BLK_INTEGRITY_CSUM_IP:
161 pr_err("IBLOCK export of blk_integrity: %s not supported\n",
162 blk_integrity_profile_name(bi));
163 ret = -ENOSYS;
164 goto out_blkdev_put;
165 case BLK_INTEGRITY_CSUM_CRC:
166 if (bi->flags & BLK_INTEGRITY_REF_TAG)
167 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE1_PROT;
168 else
169 dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE3_PROT;
170 break;
171 default:
172 break;
173 }
174
175 dev->dev_attrib.hw_pi_prot_type = dev->dev_attrib.pi_prot_type;
176 return 0;
177
178 out_blkdev_put:
179 fput(ib_dev->ibd_bdev_file);
180 out_free_bioset:
181 bioset_exit(&ib_dev->ibd_bio_set);
182 out:
183 return ret;
184 }
185
iblock_dev_call_rcu(struct rcu_head * p)186 static void iblock_dev_call_rcu(struct rcu_head *p)
187 {
188 struct se_device *dev = container_of(p, struct se_device, rcu_head);
189 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
190
191 kfree(ib_dev->ibd_plug);
192 kfree(ib_dev);
193 }
194
iblock_free_device(struct se_device * dev)195 static void iblock_free_device(struct se_device *dev)
196 {
197 call_rcu(&dev->rcu_head, iblock_dev_call_rcu);
198 }
199
iblock_destroy_device(struct se_device * dev)200 static void iblock_destroy_device(struct se_device *dev)
201 {
202 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
203
204 if (ib_dev->ibd_bdev_file)
205 fput(ib_dev->ibd_bdev_file);
206 bioset_exit(&ib_dev->ibd_bio_set);
207 }
208
iblock_plug_device(struct se_device * se_dev)209 static struct se_dev_plug *iblock_plug_device(struct se_device *se_dev)
210 {
211 struct iblock_dev *ib_dev = IBLOCK_DEV(se_dev);
212 struct iblock_dev_plug *ib_dev_plug;
213
214 /*
215 * Each se_device has a per cpu work this can be run from. We
216 * shouldn't have multiple threads on the same cpu calling this
217 * at the same time.
218 */
219 ib_dev_plug = &ib_dev->ibd_plug[raw_smp_processor_id()];
220 if (test_and_set_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags))
221 return NULL;
222
223 blk_start_plug(&ib_dev_plug->blk_plug);
224 return &ib_dev_plug->se_plug;
225 }
226
iblock_unplug_device(struct se_dev_plug * se_plug)227 static void iblock_unplug_device(struct se_dev_plug *se_plug)
228 {
229 struct iblock_dev_plug *ib_dev_plug = container_of(se_plug,
230 struct iblock_dev_plug, se_plug);
231
232 blk_finish_plug(&ib_dev_plug->blk_plug);
233 clear_bit(IBD_PLUGF_PLUGGED, &ib_dev_plug->flags);
234 }
235
iblock_get_blocks(struct se_device * dev)236 static sector_t iblock_get_blocks(struct se_device *dev)
237 {
238 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
239 u32 block_size = bdev_logical_block_size(ib_dev->ibd_bd);
240 unsigned long long blocks_long =
241 div_u64(bdev_nr_bytes(ib_dev->ibd_bd), block_size) - 1;
242
243 if (block_size == dev->dev_attrib.block_size)
244 return blocks_long;
245
246 switch (block_size) {
247 case 4096:
248 switch (dev->dev_attrib.block_size) {
249 case 2048:
250 blocks_long <<= 1;
251 break;
252 case 1024:
253 blocks_long <<= 2;
254 break;
255 case 512:
256 blocks_long <<= 3;
257 break;
258 default:
259 break;
260 }
261 break;
262 case 2048:
263 switch (dev->dev_attrib.block_size) {
264 case 4096:
265 blocks_long >>= 1;
266 break;
267 case 1024:
268 blocks_long <<= 1;
269 break;
270 case 512:
271 blocks_long <<= 2;
272 break;
273 default:
274 break;
275 }
276 break;
277 case 1024:
278 switch (dev->dev_attrib.block_size) {
279 case 4096:
280 blocks_long >>= 2;
281 break;
282 case 2048:
283 blocks_long >>= 1;
284 break;
285 case 512:
286 blocks_long <<= 1;
287 break;
288 default:
289 break;
290 }
291 break;
292 case 512:
293 switch (dev->dev_attrib.block_size) {
294 case 4096:
295 blocks_long >>= 3;
296 break;
297 case 2048:
298 blocks_long >>= 2;
299 break;
300 case 1024:
301 blocks_long >>= 1;
302 break;
303 default:
304 break;
305 }
306 break;
307 default:
308 break;
309 }
310
311 return blocks_long;
312 }
313
iblock_complete_cmd(struct se_cmd * cmd,blk_status_t blk_status)314 static void iblock_complete_cmd(struct se_cmd *cmd, blk_status_t blk_status)
315 {
316 struct iblock_req *ibr = cmd->priv;
317 u8 status;
318
319 if (!refcount_dec_and_test(&ibr->pending))
320 return;
321
322 if (blk_status == BLK_STS_RESV_CONFLICT)
323 status = SAM_STAT_RESERVATION_CONFLICT;
324 else if (atomic_read(&ibr->ib_bio_err_cnt))
325 status = SAM_STAT_CHECK_CONDITION;
326 else
327 status = SAM_STAT_GOOD;
328
329 target_complete_cmd(cmd, status);
330 kfree(ibr);
331 }
332
iblock_bio_done(struct bio * bio)333 static void iblock_bio_done(struct bio *bio)
334 {
335 struct se_cmd *cmd = bio->bi_private;
336 struct iblock_req *ibr = cmd->priv;
337 blk_status_t blk_status = bio->bi_status;
338
339 if (bio->bi_status) {
340 pr_err("bio error: %p, err: %d\n", bio, bio->bi_status);
341 /*
342 * Bump the ib_bio_err_cnt and release bio.
343 */
344 atomic_inc(&ibr->ib_bio_err_cnt);
345 smp_mb__after_atomic();
346 }
347
348 bio_put(bio);
349
350 iblock_complete_cmd(cmd, blk_status);
351 }
352
iblock_get_bio(struct se_cmd * cmd,sector_t lba,u32 sg_num,blk_opf_t opf)353 static struct bio *iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num,
354 blk_opf_t opf)
355 {
356 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
357 struct bio *bio;
358
359 /*
360 * Only allocate as many vector entries as the bio code allows us to,
361 * we'll loop later on until we have handled the whole request.
362 */
363 bio = bio_alloc_bioset(ib_dev->ibd_bd, bio_max_segs(sg_num), opf,
364 GFP_NOIO, &ib_dev->ibd_bio_set);
365 if (!bio) {
366 pr_err("Unable to allocate memory for bio\n");
367 return NULL;
368 }
369
370 bio->bi_private = cmd;
371 bio->bi_end_io = &iblock_bio_done;
372 bio->bi_iter.bi_sector = lba;
373
374 return bio;
375 }
376
iblock_submit_bios(struct bio_list * list)377 static void iblock_submit_bios(struct bio_list *list)
378 {
379 struct blk_plug plug;
380 struct bio *bio;
381 /*
382 * The block layer handles nested plugs, so just plug/unplug to handle
383 * fabric drivers that didn't support batching and multi bio cmds.
384 */
385 blk_start_plug(&plug);
386 while ((bio = bio_list_pop(list)))
387 submit_bio(bio);
388 blk_finish_plug(&plug);
389 }
390
iblock_end_io_flush(struct bio * bio)391 static void iblock_end_io_flush(struct bio *bio)
392 {
393 struct se_cmd *cmd = bio->bi_private;
394
395 if (bio->bi_status)
396 pr_err("IBLOCK: cache flush failed: %d\n", bio->bi_status);
397
398 if (cmd) {
399 if (bio->bi_status)
400 target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
401 else
402 target_complete_cmd(cmd, SAM_STAT_GOOD);
403 }
404
405 bio_put(bio);
406 }
407
408 /*
409 * Implement SYCHRONIZE CACHE. Note that we can't handle lba ranges and must
410 * always flush the whole cache.
411 */
412 static sense_reason_t
iblock_execute_sync_cache(struct se_cmd * cmd)413 iblock_execute_sync_cache(struct se_cmd *cmd)
414 {
415 struct iblock_dev *ib_dev = IBLOCK_DEV(cmd->se_dev);
416 int immed = (cmd->t_task_cdb[1] & 0x2);
417 struct bio *bio;
418
419 /*
420 * If the Immediate bit is set, queue up the GOOD response
421 * for this SYNCHRONIZE_CACHE op.
422 */
423 if (immed)
424 target_complete_cmd(cmd, SAM_STAT_GOOD);
425
426 bio = bio_alloc(ib_dev->ibd_bd, 0, REQ_OP_WRITE | REQ_PREFLUSH,
427 GFP_KERNEL);
428 bio->bi_end_io = iblock_end_io_flush;
429 if (!immed)
430 bio->bi_private = cmd;
431 submit_bio(bio);
432 return 0;
433 }
434
435 static sense_reason_t
iblock_execute_unmap(struct se_cmd * cmd,sector_t lba,sector_t nolb)436 iblock_execute_unmap(struct se_cmd *cmd, sector_t lba, sector_t nolb)
437 {
438 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
439 struct se_device *dev = cmd->se_dev;
440 int ret;
441
442 ret = blkdev_issue_discard(bdev,
443 target_to_linux_sector(dev, lba),
444 target_to_linux_sector(dev, nolb),
445 GFP_KERNEL);
446 if (ret < 0) {
447 pr_err("blkdev_issue_discard() failed: %d\n", ret);
448 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
449 }
450
451 return 0;
452 }
453
454 static sense_reason_t
iblock_execute_zero_out(struct block_device * bdev,struct se_cmd * cmd)455 iblock_execute_zero_out(struct block_device *bdev, struct se_cmd *cmd)
456 {
457 struct se_device *dev = cmd->se_dev;
458 struct scatterlist *sg = &cmd->t_data_sg[0];
459 unsigned char *buf, *not_zero;
460 int ret;
461
462 buf = kmap(sg_page(sg)) + sg->offset;
463 if (!buf)
464 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
465 /*
466 * Fall back to block_execute_write_same() slow-path if
467 * incoming WRITE_SAME payload does not contain zeros.
468 */
469 not_zero = memchr_inv(buf, 0x00, cmd->data_length);
470 kunmap(sg_page(sg));
471
472 if (not_zero)
473 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
474
475 ret = blkdev_issue_zeroout(bdev,
476 target_to_linux_sector(dev, cmd->t_task_lba),
477 target_to_linux_sector(dev,
478 sbc_get_write_same_sectors(cmd)),
479 GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
480 if (ret)
481 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
482
483 target_complete_cmd(cmd, SAM_STAT_GOOD);
484 return 0;
485 }
486
487 static sense_reason_t
iblock_execute_write_same(struct se_cmd * cmd)488 iblock_execute_write_same(struct se_cmd *cmd)
489 {
490 struct block_device *bdev = IBLOCK_DEV(cmd->se_dev)->ibd_bd;
491 struct iblock_req *ibr;
492 struct scatterlist *sg;
493 struct bio *bio;
494 struct bio_list list;
495 struct se_device *dev = cmd->se_dev;
496 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
497 sector_t sectors = target_to_linux_sector(dev,
498 sbc_get_write_same_sectors(cmd));
499
500 if (cmd->prot_op) {
501 pr_err("WRITE_SAME: Protection information with IBLOCK"
502 " backends not supported\n");
503 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
504 }
505
506 if (!cmd->t_data_nents)
507 return TCM_INVALID_CDB_FIELD;
508
509 sg = &cmd->t_data_sg[0];
510
511 if (cmd->t_data_nents > 1 ||
512 sg->length != cmd->se_dev->dev_attrib.block_size) {
513 pr_err("WRITE_SAME: Illegal SGL t_data_nents: %u length: %u"
514 " block_size: %u\n", cmd->t_data_nents, sg->length,
515 cmd->se_dev->dev_attrib.block_size);
516 return TCM_INVALID_CDB_FIELD;
517 }
518
519 if (bdev_write_zeroes_sectors(bdev)) {
520 if (!iblock_execute_zero_out(bdev, cmd))
521 return 0;
522 }
523
524 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
525 if (!ibr)
526 goto fail;
527 cmd->priv = ibr;
528
529 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
530 if (!bio)
531 goto fail_free_ibr;
532
533 bio_list_init(&list);
534 bio_list_add(&list, bio);
535
536 refcount_set(&ibr->pending, 1);
537
538 while (sectors) {
539 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
540 != sg->length) {
541
542 bio = iblock_get_bio(cmd, block_lba, 1, REQ_OP_WRITE);
543 if (!bio)
544 goto fail_put_bios;
545
546 refcount_inc(&ibr->pending);
547 bio_list_add(&list, bio);
548 }
549
550 /* Always in 512 byte units for Linux/Block */
551 block_lba += sg->length >> SECTOR_SHIFT;
552 sectors -= sg->length >> SECTOR_SHIFT;
553 }
554
555 iblock_submit_bios(&list);
556 return 0;
557
558 fail_put_bios:
559 while ((bio = bio_list_pop(&list)))
560 bio_put(bio);
561 fail_free_ibr:
562 kfree(ibr);
563 fail:
564 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
565 }
566
567 enum {
568 Opt_udev_path, Opt_readonly, Opt_force, Opt_exclusive, Opt_err,
569 };
570
571 static match_table_t tokens = {
572 {Opt_udev_path, "udev_path=%s"},
573 {Opt_readonly, "readonly=%d"},
574 {Opt_force, "force=%d"},
575 {Opt_exclusive, "exclusive=%d"},
576 {Opt_err, NULL}
577 };
578
iblock_set_configfs_dev_params(struct se_device * dev,const char * page,ssize_t count)579 static ssize_t iblock_set_configfs_dev_params(struct se_device *dev,
580 const char *page, ssize_t count)
581 {
582 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
583 char *orig, *ptr, *arg_p, *opts;
584 substring_t args[MAX_OPT_ARGS];
585 int ret = 0, token, tmp_exclusive;
586 unsigned long tmp_readonly;
587
588 opts = kstrdup(page, GFP_KERNEL);
589 if (!opts)
590 return -ENOMEM;
591
592 orig = opts;
593
594 while ((ptr = strsep(&opts, ",\n")) != NULL) {
595 if (!*ptr)
596 continue;
597
598 token = match_token(ptr, tokens, args);
599 switch (token) {
600 case Opt_udev_path:
601 if (ib_dev->ibd_bd) {
602 pr_err("Unable to set udev_path= while"
603 " ib_dev->ibd_bd exists\n");
604 ret = -EEXIST;
605 goto out;
606 }
607 if (match_strlcpy(ib_dev->ibd_udev_path, &args[0],
608 SE_UDEV_PATH_LEN) == 0) {
609 ret = -EINVAL;
610 break;
611 }
612 pr_debug("IBLOCK: Referencing UDEV path: %s\n",
613 ib_dev->ibd_udev_path);
614 ib_dev->ibd_flags |= IBDF_HAS_UDEV_PATH;
615 break;
616 case Opt_readonly:
617 arg_p = match_strdup(&args[0]);
618 if (!arg_p) {
619 ret = -ENOMEM;
620 break;
621 }
622 ret = kstrtoul(arg_p, 0, &tmp_readonly);
623 kfree(arg_p);
624 if (ret < 0) {
625 pr_err("kstrtoul() failed for"
626 " readonly=\n");
627 goto out;
628 }
629 ib_dev->ibd_readonly = tmp_readonly;
630 pr_debug("IBLOCK: readonly: %d\n", ib_dev->ibd_readonly);
631 break;
632 case Opt_exclusive:
633 arg_p = match_strdup(&args[0]);
634 if (!arg_p) {
635 ret = -ENOMEM;
636 break;
637 }
638 ret = kstrtoint(arg_p, 0, &tmp_exclusive);
639 kfree(arg_p);
640 if (ret < 0) {
641 pr_err("kstrtoul() failed for exclusive=\n");
642 goto out;
643 }
644 ib_dev->ibd_exclusive = tmp_exclusive;
645 pr_debug("IBLOCK: exclusive: %d\n",
646 ib_dev->ibd_exclusive);
647 break;
648 case Opt_force:
649 break;
650 default:
651 break;
652 }
653 }
654
655 out:
656 kfree(orig);
657 return (!ret) ? count : ret;
658 }
659
iblock_show_configfs_dev_params(struct se_device * dev,char * b)660 static ssize_t iblock_show_configfs_dev_params(struct se_device *dev, char *b)
661 {
662 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
663 struct block_device *bd = ib_dev->ibd_bd;
664 ssize_t bl = 0;
665
666 if (bd)
667 bl += sprintf(b + bl, "iBlock device: %pg", bd);
668 if (ib_dev->ibd_flags & IBDF_HAS_UDEV_PATH)
669 bl += sprintf(b + bl, " UDEV PATH: %s",
670 ib_dev->ibd_udev_path);
671 bl += sprintf(b + bl, " readonly: %d\n", ib_dev->ibd_readonly);
672 bl += sprintf(b + bl, " exclusive: %d\n", ib_dev->ibd_exclusive);
673
674 bl += sprintf(b + bl, " ");
675 if (bd) {
676 bl += sprintf(b + bl, "Major: %d Minor: %d %s\n",
677 MAJOR(bd->bd_dev), MINOR(bd->bd_dev),
678 "CLAIMED: IBLOCK");
679 } else {
680 bl += sprintf(b + bl, "Major: 0 Minor: 0\n");
681 }
682
683 return bl;
684 }
685
686 static int
iblock_alloc_bip(struct se_cmd * cmd,struct bio * bio,struct sg_mapping_iter * miter)687 iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio,
688 struct sg_mapping_iter *miter)
689 {
690 struct se_device *dev = cmd->se_dev;
691 struct blk_integrity *bi;
692 struct bio_integrity_payload *bip;
693 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
694 int rc;
695 size_t resid, len;
696
697 bi = bdev_get_integrity(ib_dev->ibd_bd);
698 if (!bi) {
699 pr_err("Unable to locate bio_integrity\n");
700 return -ENODEV;
701 }
702
703 bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents));
704 if (IS_ERR(bip)) {
705 pr_err("Unable to allocate bio_integrity_payload\n");
706 return PTR_ERR(bip);
707 }
708
709 /* virtual start sector must be in integrity interval units */
710 bip_set_seed(bip, bio->bi_iter.bi_sector >>
711 (bi->interval_exp - SECTOR_SHIFT));
712
713 pr_debug("IBLOCK BIP Size: %u Sector: %llu\n", bip->bip_iter.bi_size,
714 (unsigned long long)bip->bip_iter.bi_sector);
715
716 resid = bio_integrity_bytes(bi, bio_sectors(bio));
717 while (resid > 0 && sg_miter_next(miter)) {
718
719 len = min_t(size_t, miter->length, resid);
720 rc = bio_integrity_add_page(bio, miter->page, len,
721 offset_in_page(miter->addr));
722 if (rc != len) {
723 pr_err("bio_integrity_add_page() failed; %d\n", rc);
724 sg_miter_stop(miter);
725 return -ENOMEM;
726 }
727
728 pr_debug("Added bio integrity page: %p length: %zu offset: %lu\n",
729 miter->page, len, offset_in_page(miter->addr));
730
731 resid -= len;
732 if (len < miter->length)
733 miter->consumed -= miter->length - len;
734 }
735 sg_miter_stop(miter);
736
737 return 0;
738 }
739
740 static sense_reason_t
iblock_execute_rw(struct se_cmd * cmd,struct scatterlist * sgl,u32 sgl_nents,enum dma_data_direction data_direction)741 iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
742 enum dma_data_direction data_direction)
743 {
744 struct se_device *dev = cmd->se_dev;
745 sector_t block_lba = target_to_linux_sector(dev, cmd->t_task_lba);
746 struct iblock_req *ibr;
747 struct bio *bio;
748 struct bio_list list;
749 struct scatterlist *sg;
750 u32 sg_num = sgl_nents;
751 blk_opf_t opf;
752 unsigned bio_cnt;
753 int i, rc;
754 struct sg_mapping_iter prot_miter;
755 unsigned int miter_dir;
756
757 if (data_direction == DMA_TO_DEVICE) {
758 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
759
760 /*
761 * Set bits to indicate WRITE_ODIRECT so we are not throttled
762 * by WBT.
763 */
764 opf = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
765 /*
766 * Force writethrough using REQ_FUA if a volatile write cache
767 * is not enabled, or if initiator set the Force Unit Access bit.
768 */
769 miter_dir = SG_MITER_TO_SG;
770 if (bdev_fua(ib_dev->ibd_bd)) {
771 if (cmd->se_cmd_flags & SCF_FUA)
772 opf |= REQ_FUA;
773 else if (!bdev_write_cache(ib_dev->ibd_bd))
774 opf |= REQ_FUA;
775 }
776 } else {
777 opf = REQ_OP_READ;
778 miter_dir = SG_MITER_FROM_SG;
779 }
780
781 ibr = kzalloc(sizeof(struct iblock_req), GFP_KERNEL);
782 if (!ibr)
783 goto fail;
784 cmd->priv = ibr;
785
786 if (!sgl_nents) {
787 refcount_set(&ibr->pending, 1);
788 iblock_complete_cmd(cmd, BLK_STS_OK);
789 return 0;
790 }
791
792 bio = iblock_get_bio(cmd, block_lba, sgl_nents, opf);
793 if (!bio)
794 goto fail_free_ibr;
795
796 bio_list_init(&list);
797 bio_list_add(&list, bio);
798
799 refcount_set(&ibr->pending, 2);
800 bio_cnt = 1;
801
802 if (cmd->prot_type && dev->dev_attrib.pi_prot_type)
803 sg_miter_start(&prot_miter, cmd->t_prot_sg, cmd->t_prot_nents,
804 miter_dir);
805
806 for_each_sg(sgl, sg, sgl_nents, i) {
807 /*
808 * XXX: if the length the device accepts is shorter than the
809 * length of the S/G list entry this will cause and
810 * endless loop. Better hope no driver uses huge pages.
811 */
812 while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
813 != sg->length) {
814 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
815 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
816 if (rc)
817 goto fail_put_bios;
818 }
819
820 if (bio_cnt >= IBLOCK_MAX_BIO_PER_TASK) {
821 iblock_submit_bios(&list);
822 bio_cnt = 0;
823 }
824
825 bio = iblock_get_bio(cmd, block_lba, sg_num, opf);
826 if (!bio)
827 goto fail_put_bios;
828
829 refcount_inc(&ibr->pending);
830 bio_list_add(&list, bio);
831 bio_cnt++;
832 }
833
834 /* Always in 512 byte units for Linux/Block */
835 block_lba += sg->length >> SECTOR_SHIFT;
836 sg_num--;
837 }
838
839 if (cmd->prot_type && dev->dev_attrib.pi_prot_type) {
840 rc = iblock_alloc_bip(cmd, bio, &prot_miter);
841 if (rc)
842 goto fail_put_bios;
843 }
844
845 iblock_submit_bios(&list);
846 iblock_complete_cmd(cmd, BLK_STS_OK);
847 return 0;
848
849 fail_put_bios:
850 while ((bio = bio_list_pop(&list)))
851 bio_put(bio);
852 fail_free_ibr:
853 kfree(ibr);
854 fail:
855 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
856 }
857
iblock_execute_pr_out(struct se_cmd * cmd,u8 sa,u64 key,u64 sa_key,u8 type,bool aptpl)858 static sense_reason_t iblock_execute_pr_out(struct se_cmd *cmd, u8 sa, u64 key,
859 u64 sa_key, u8 type, bool aptpl)
860 {
861 struct se_device *dev = cmd->se_dev;
862 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
863 struct block_device *bdev = ib_dev->ibd_bd;
864 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
865 int ret;
866
867 if (!ops) {
868 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
869 return TCM_UNSUPPORTED_SCSI_OPCODE;
870 }
871
872 switch (sa) {
873 case PRO_REGISTER:
874 case PRO_REGISTER_AND_IGNORE_EXISTING_KEY:
875 if (!ops->pr_register) {
876 pr_err("block device does not support pr_register.\n");
877 return TCM_UNSUPPORTED_SCSI_OPCODE;
878 }
879
880 /* The block layer pr ops always enables aptpl */
881 if (!aptpl)
882 pr_info("APTPL not set by initiator, but will be used.\n");
883
884 ret = ops->pr_register(bdev, key, sa_key,
885 sa == PRO_REGISTER ? 0 : PR_FL_IGNORE_KEY);
886 break;
887 case PRO_RESERVE:
888 if (!ops->pr_reserve) {
889 pr_err("block_device does not support pr_reserve.\n");
890 return TCM_UNSUPPORTED_SCSI_OPCODE;
891 }
892
893 ret = ops->pr_reserve(bdev, key, scsi_pr_type_to_block(type), 0);
894 break;
895 case PRO_CLEAR:
896 if (!ops->pr_clear) {
897 pr_err("block_device does not support pr_clear.\n");
898 return TCM_UNSUPPORTED_SCSI_OPCODE;
899 }
900
901 ret = ops->pr_clear(bdev, key);
902 break;
903 case PRO_PREEMPT:
904 case PRO_PREEMPT_AND_ABORT:
905 if (!ops->pr_clear) {
906 pr_err("block_device does not support pr_preempt.\n");
907 return TCM_UNSUPPORTED_SCSI_OPCODE;
908 }
909
910 ret = ops->pr_preempt(bdev, key, sa_key,
911 scsi_pr_type_to_block(type),
912 sa == PRO_PREEMPT_AND_ABORT);
913 break;
914 case PRO_RELEASE:
915 if (!ops->pr_clear) {
916 pr_err("block_device does not support pr_pclear.\n");
917 return TCM_UNSUPPORTED_SCSI_OPCODE;
918 }
919
920 ret = ops->pr_release(bdev, key, scsi_pr_type_to_block(type));
921 break;
922 default:
923 pr_err("Unknown PERSISTENT_RESERVE_OUT SA: 0x%02x\n", sa);
924 return TCM_UNSUPPORTED_SCSI_OPCODE;
925 }
926
927 if (!ret)
928 return TCM_NO_SENSE;
929 else if (ret == PR_STS_RESERVATION_CONFLICT)
930 return TCM_RESERVATION_CONFLICT;
931 else
932 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
933 }
934
iblock_pr_report_caps(unsigned char * param_data)935 static void iblock_pr_report_caps(unsigned char *param_data)
936 {
937 u16 len = 8;
938
939 put_unaligned_be16(len, ¶m_data[0]);
940 /*
941 * When using the pr_ops passthrough method we only support exporting
942 * the device through one target port because from the backend module
943 * level we can't see the target port config. As a result we only
944 * support registration directly from the I_T nexus the cmd is sent
945 * through and do not set ATP_C here.
946 *
947 * The block layer pr_ops do not support passing in initiators so
948 * we don't set SIP_C here.
949 */
950 /* PTPL_C: Persistence across Target Power Loss bit */
951 param_data[2] |= 0x01;
952 /*
953 * We are filling in the PERSISTENT RESERVATION TYPE MASK below, so
954 * set the TMV: Task Mask Valid bit.
955 */
956 param_data[3] |= 0x80;
957 /*
958 * Change ALLOW COMMANDs to 0x20 or 0x40 later from Table 166
959 */
960 param_data[3] |= 0x10; /* ALLOW COMMANDs field 001b */
961 /*
962 * PTPL_A: Persistence across Target Power Loss Active bit. The block
963 * layer pr ops always enables this so report it active.
964 */
965 param_data[3] |= 0x01;
966 /*
967 * Setup the PERSISTENT RESERVATION TYPE MASK from Table 212 spc4r37.
968 */
969 param_data[4] |= 0x80; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
970 param_data[4] |= 0x40; /* PR_TYPE_EXCLUSIVE_ACCESS_REGONLY */
971 param_data[4] |= 0x20; /* PR_TYPE_WRITE_EXCLUSIVE_REGONLY */
972 param_data[4] |= 0x08; /* PR_TYPE_EXCLUSIVE_ACCESS */
973 param_data[4] |= 0x02; /* PR_TYPE_WRITE_EXCLUSIVE */
974 param_data[5] |= 0x01; /* PR_TYPE_EXCLUSIVE_ACCESS_ALLREG */
975 }
976
iblock_pr_read_keys(struct se_cmd * cmd,unsigned char * param_data)977 static sense_reason_t iblock_pr_read_keys(struct se_cmd *cmd,
978 unsigned char *param_data)
979 {
980 struct se_device *dev = cmd->se_dev;
981 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
982 struct block_device *bdev = ib_dev->ibd_bd;
983 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
984 int i, len, paths, data_offset;
985 struct pr_keys *keys;
986 sense_reason_t ret;
987
988 if (!ops) {
989 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
990 return TCM_UNSUPPORTED_SCSI_OPCODE;
991 }
992
993 if (!ops->pr_read_keys) {
994 pr_err("Block device does not support read_keys.\n");
995 return TCM_UNSUPPORTED_SCSI_OPCODE;
996 }
997
998 /*
999 * We don't know what's under us, but dm-multipath will register every
1000 * path with the same key, so start off with enough space for 16 paths.
1001 * which is not a lot of memory and should normally be enough.
1002 */
1003 paths = 16;
1004 retry:
1005 len = 8 * paths;
1006 keys = kzalloc(sizeof(*keys) + len, GFP_KERNEL);
1007 if (!keys)
1008 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1009
1010 keys->num_keys = paths;
1011 if (!ops->pr_read_keys(bdev, keys)) {
1012 if (keys->num_keys > paths) {
1013 kfree(keys);
1014 paths *= 2;
1015 goto retry;
1016 }
1017 } else {
1018 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1019 goto free_keys;
1020 }
1021
1022 ret = TCM_NO_SENSE;
1023
1024 put_unaligned_be32(keys->generation, ¶m_data[0]);
1025 if (!keys->num_keys) {
1026 put_unaligned_be32(0, ¶m_data[4]);
1027 goto free_keys;
1028 }
1029
1030 put_unaligned_be32(8 * keys->num_keys, ¶m_data[4]);
1031
1032 data_offset = 8;
1033 for (i = 0; i < keys->num_keys; i++) {
1034 if (data_offset + 8 > cmd->data_length)
1035 break;
1036
1037 put_unaligned_be64(keys->keys[i], ¶m_data[data_offset]);
1038 data_offset += 8;
1039 }
1040
1041 free_keys:
1042 kfree(keys);
1043 return ret;
1044 }
1045
iblock_pr_read_reservation(struct se_cmd * cmd,unsigned char * param_data)1046 static sense_reason_t iblock_pr_read_reservation(struct se_cmd *cmd,
1047 unsigned char *param_data)
1048 {
1049 struct se_device *dev = cmd->se_dev;
1050 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1051 struct block_device *bdev = ib_dev->ibd_bd;
1052 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
1053 struct pr_held_reservation rsv = { };
1054
1055 if (!ops) {
1056 pr_err("Block device does not support pr_ops but iblock device has been configured for PR passthrough.\n");
1057 return TCM_UNSUPPORTED_SCSI_OPCODE;
1058 }
1059
1060 if (!ops->pr_read_reservation) {
1061 pr_err("Block device does not support read_keys.\n");
1062 return TCM_UNSUPPORTED_SCSI_OPCODE;
1063 }
1064
1065 if (ops->pr_read_reservation(bdev, &rsv))
1066 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1067
1068 put_unaligned_be32(rsv.generation, ¶m_data[0]);
1069 if (!block_pr_type_to_scsi(rsv.type)) {
1070 put_unaligned_be32(0, ¶m_data[4]);
1071 return TCM_NO_SENSE;
1072 }
1073
1074 put_unaligned_be32(16, ¶m_data[4]);
1075
1076 if (cmd->data_length < 16)
1077 return TCM_NO_SENSE;
1078 put_unaligned_be64(rsv.key, ¶m_data[8]);
1079
1080 if (cmd->data_length < 22)
1081 return TCM_NO_SENSE;
1082 param_data[21] = block_pr_type_to_scsi(rsv.type);
1083
1084 return TCM_NO_SENSE;
1085 }
1086
iblock_execute_pr_in(struct se_cmd * cmd,u8 sa,unsigned char * param_data)1087 static sense_reason_t iblock_execute_pr_in(struct se_cmd *cmd, u8 sa,
1088 unsigned char *param_data)
1089 {
1090 sense_reason_t ret = TCM_NO_SENSE;
1091
1092 switch (sa) {
1093 case PRI_REPORT_CAPABILITIES:
1094 iblock_pr_report_caps(param_data);
1095 break;
1096 case PRI_READ_KEYS:
1097 ret = iblock_pr_read_keys(cmd, param_data);
1098 break;
1099 case PRI_READ_RESERVATION:
1100 ret = iblock_pr_read_reservation(cmd, param_data);
1101 break;
1102 default:
1103 pr_err("Unknown PERSISTENT_RESERVE_IN SA: 0x%02x\n", sa);
1104 return TCM_UNSUPPORTED_SCSI_OPCODE;
1105 }
1106
1107 return ret;
1108 }
1109
iblock_get_alignment_offset_lbas(struct se_device * dev)1110 static sector_t iblock_get_alignment_offset_lbas(struct se_device *dev)
1111 {
1112 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1113 struct block_device *bd = ib_dev->ibd_bd;
1114 int ret;
1115
1116 ret = bdev_alignment_offset(bd);
1117 if (ret == -1)
1118 return 0;
1119
1120 /* convert offset-bytes to offset-lbas */
1121 return ret / bdev_logical_block_size(bd);
1122 }
1123
iblock_get_lbppbe(struct se_device * dev)1124 static unsigned int iblock_get_lbppbe(struct se_device *dev)
1125 {
1126 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1127 struct block_device *bd = ib_dev->ibd_bd;
1128 unsigned int logs_per_phys =
1129 bdev_physical_block_size(bd) / bdev_logical_block_size(bd);
1130
1131 return ilog2(logs_per_phys);
1132 }
1133
iblock_get_io_min(struct se_device * dev)1134 static unsigned int iblock_get_io_min(struct se_device *dev)
1135 {
1136 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1137 struct block_device *bd = ib_dev->ibd_bd;
1138
1139 return bdev_io_min(bd);
1140 }
1141
iblock_get_io_opt(struct se_device * dev)1142 static unsigned int iblock_get_io_opt(struct se_device *dev)
1143 {
1144 struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
1145 struct block_device *bd = ib_dev->ibd_bd;
1146
1147 return bdev_io_opt(bd);
1148 }
1149
1150 static struct exec_cmd_ops iblock_exec_cmd_ops = {
1151 .execute_rw = iblock_execute_rw,
1152 .execute_sync_cache = iblock_execute_sync_cache,
1153 .execute_write_same = iblock_execute_write_same,
1154 .execute_unmap = iblock_execute_unmap,
1155 .execute_pr_out = iblock_execute_pr_out,
1156 .execute_pr_in = iblock_execute_pr_in,
1157 };
1158
1159 static sense_reason_t
iblock_parse_cdb(struct se_cmd * cmd)1160 iblock_parse_cdb(struct se_cmd *cmd)
1161 {
1162 return sbc_parse_cdb(cmd, &iblock_exec_cmd_ops);
1163 }
1164
iblock_get_write_cache(struct se_device * dev)1165 static bool iblock_get_write_cache(struct se_device *dev)
1166 {
1167 return bdev_write_cache(IBLOCK_DEV(dev)->ibd_bd);
1168 }
1169
1170 static const struct target_backend_ops iblock_ops = {
1171 .name = "iblock",
1172 .inquiry_prod = "IBLOCK",
1173 .transport_flags_changeable = TRANSPORT_FLAG_PASSTHROUGH_PGR,
1174 .inquiry_rev = IBLOCK_VERSION,
1175 .owner = THIS_MODULE,
1176 .attach_hba = iblock_attach_hba,
1177 .detach_hba = iblock_detach_hba,
1178 .alloc_device = iblock_alloc_device,
1179 .configure_device = iblock_configure_device,
1180 .destroy_device = iblock_destroy_device,
1181 .free_device = iblock_free_device,
1182 .configure_unmap = iblock_configure_unmap,
1183 .plug_device = iblock_plug_device,
1184 .unplug_device = iblock_unplug_device,
1185 .parse_cdb = iblock_parse_cdb,
1186 .set_configfs_dev_params = iblock_set_configfs_dev_params,
1187 .show_configfs_dev_params = iblock_show_configfs_dev_params,
1188 .get_device_type = sbc_get_device_type,
1189 .get_blocks = iblock_get_blocks,
1190 .get_alignment_offset_lbas = iblock_get_alignment_offset_lbas,
1191 .get_lbppbe = iblock_get_lbppbe,
1192 .get_io_min = iblock_get_io_min,
1193 .get_io_opt = iblock_get_io_opt,
1194 .get_write_cache = iblock_get_write_cache,
1195 .tb_dev_attrib_attrs = sbc_attrib_attrs,
1196 };
1197
iblock_module_init(void)1198 static int __init iblock_module_init(void)
1199 {
1200 return transport_backend_register(&iblock_ops);
1201 }
1202
iblock_module_exit(void)1203 static void __exit iblock_module_exit(void)
1204 {
1205 target_backend_unregister(&iblock_ops);
1206 }
1207
1208 MODULE_DESCRIPTION("TCM IBLOCK subsystem plugin");
1209 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1210 MODULE_LICENSE("GPL");
1211
1212 module_init(iblock_module_init);
1213 module_exit(iblock_module_exit);
1214